Vitamin B3 (Niacin)

BACKGROUND: Nicotinamide is the active form of vitamin B3 (niacin) obtained through endogenous synthesis, mainly through tryptophan metabolism and dietary supplements, fish, meats, grains, and dairy products. It participates in cellular energy metabolism and modulates multiple cellular survival and death pathways. Nicotinamide has been widely studied as a safe chemopreventive agent that reduces actinic keratosis (AKs) and non-melanoma skin cancers (NMSC). METHODS: We used the Medline, EMBASE, PubMed, and Cochrane databases to search the concepts "nicotinamide", "chemoprevention", and "skin cancer" up to August 2023. Three independent authors screened titles and abstracts for intervention and study design before searching full texts for eligibility criteria. The primary outcome was the impact of oral nicotinamide on the incidence of NMSC in high-risk patients. We also conducted a systematic search to identify relevant epidemiological studies published evaluating dietary niacin intake and the risk of NMSC. RESULTS: Two hundred and twenty-five studies were reviewed, and four met the inclusion criteria. There was no association between NAM consumption and risk for squamous cell carcinoma (SCC) (rate ratio (RR) 0.81, 95% CI 0.48-1.37; I2 = 0%), basal cell carcinoma (BCC) (RR 0.88, 95% CI 0.50-1.55; I2 = 63%), and NMSC (RR 0.82, 95% CI 0.61-1.12; I2 = 63%). Adverse events were rare and acceptable, allowing optimal compliance of patients to the treatment. We found only one article evaluating the association between niacin dietary intake and NMSC risk, supporting a potential beneficial role of niacin intake concerning SCC but not BCC or melanoma. CONCLUSIONS: The present meta-analysis shows, by pooling immunocompetent and immunosuppressed patients, that there is insufficient evidence that oral nicotinamide therapy significantly reduces the number of keratinocyte cancers.

PURPOSE: The significance of niacin in embryonic development has clinical implications in the counseling of pregnant women and may be used to inform nutrition recommendations. This study, therefore, aims to review the associations between maternal periconceptional niacin intake and congenital anomalies. METHODS: A systematic search of Ovid MEDLINE, ClinicalTrials.gov, AMED, CENTRAL, Emcare, EMBASE, Maternity & Infant Care and Google Scholar was conducted between inception and 30 September 2020. Medical subject heading terms included "nicotinic acids" and related metabolites, "congenital anomalies" and specific types of congenital anomalies. Included studies reported the association between maternal niacin intake and congenital anomalies in their offspring and reported the measure of association. Studies involved solely the women with co-morbidities, animal, in vitro and qualitative studies were excluded. The risk of bias of included studies was assessed using the Newcastle-Ottawa Scale (NOS). A random effects-restricted maximum likelihood model was used to obtain summary estimates, and multivariable meta-regression model was used to adjust study-level covariates. RESULTS: Of 21,908 retrieved citations, 14 case-control studies including 35,743 women met the inclusion criteria. Ten studies were conducted in the U.S, three in Netherlands and one in South Africa. The meta-analysis showed that expectant mothers with an insufficient niacin intake were significantly more likely to have babies with congenital abnormalities (odds ratio 1.13, 95% confidence interval 1.02-1.24) compared to mothers with adequate niacin intake. A similar association between niacin deficiency and congenital anomalies was observed (OR 1.15, 95% CI 1.03-1.26) when sensitivity analysis was conducted by quality of the included studies. Meta-regression showed neither statistically significant impact of study size (p = 0.859) nor time of niacin assessment (p = 0.127). The overall quality of evidence used is high-thirteen studies achieved a rating of six or seven stars out of a possible nine based on the NOS. CONCLUSION: Inadequate maternal niacin intake is associated with an increased risk of conge

CONTEXT: Nicotinic acid and nicotinamide are soluble compounds of the vitamin B group, widely used to regulate the lipid profile in hyperlipidemic individuals. Higher doses of nicotinic acid are associated with adverse effects, especially flushing. A unique tolerable upper intake level (UL) of nicotinic acid has not been defined. OBJECTIVE: This meta-analysis aims to evaluate adverse effects and their incidence after supplementation with different doses of nicotinic acid and nicotinamide, comparing results with current ULs in Europe and the United States. DATA SOURCES: PubMed was searched for articles providing detailed information about nicotinic acid or nicotinamide supplementation and related outcomes. STUDY SELECTION: A total of 2670 citations were selected for screening. Two primary outcomes were considered: occurrence of adverse effects following nicotinic acid or nicotinamide supplementation, and dose at which adverse effects occurred. DATA EXTRACTION: Details on study population, type and duration of treatment, dosage of vitamins, association with lipid-influencing drugs, length of follow-up, and incidence and type of adverse events were extracted. RESULTS: After screening, 47 articles involving 11 741 individuals were included. Meta-analysis was based on estimation of benchmark doses for the probability of adverse effects after supplementation. In individuals with dyslipidemia or cardiovascular disease, nicotinic acid monotherapy seems to be protective against any adverse effects considered, as adverse events occurred at doses above those used with other treatments. In healthy individuals treated with nicotinic acid alone, major adverse effects occurred at doses below 1000 mg/d. CONCLUSIONS: Results may indicate a high degree of conservativeness in the UL of nicotinic acid, fixed at 35 mg/d in United States and 10 mg/d in Europe. Reconsideration of the UL of nicotinic acid for nutritional supplements, possibly differentiating between ULs in healthy and unhealthy individuals, may be warranted. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-

Nicotinamide adenine dinucleotide (NAD(H)) and its phosphorylated form NADP(H) are vitamin B3-derived redox cofactors essential for numerous metabolic reactions and protein modifications. Various health conditions are associated with disturbances in NAD+ homeostasis. To restore NAD+ levels, the main biosynthetic pathways have been targeted, with nicotinamide (Nam), nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN) being the most prominent boosters. However, while many preclinical studies have examined the effects of these precursors, a direct comparison in humans is lacking, and recent rodent research suggests that the NAD+-boosting effects of NR and NMN may depend on their microbial conversion to nicotinic acid (NA), a mechanism not yet confirmed in humans. Here we show in a randomized, open-label, placebo-controlled study in 65 healthy participants that 14 days of supplementation with NR and NMN, but not Nam, comparably increases circulatory NAD+ concentrations in healthy adults. Unlike the chronic effect, only Nam acutely and transiently affects the whole-blood NAD+ metabolome. Using ex vivo fermentation with human microbiota, we identify that NR and NMN give rise to NA and specifically enhance microbial growth and metabolism. We further demonstrate ex vivo in whole blood that NA is a potent NAD+ booster, while NMN, NR and Nam are not. Ultimately, we propose a gut-dependent model for the modes of action of the three NAD+ precursors with NR and NMN elevating circulatory NAD+ via the Preiss-Handler pathway, while rapidly absorbed Nam acutely affects NAD+ levels via the salvage pathway. Overall, these results indicate a dual effect of NR and NMN and their microbially produced metabolite NA: a sustained increase in systemic NAD+ levels and a potent modulator of gut health. ClinicalTrials.gov identifier: NCT05517122 . © 2026. The Author(s).

BACKGROUND: Maintaining adequate hydration is critical to optimal health, well-being, and performance. Those who are physically active in stressful environments, such as warm and/or humid scenarios, may be at particular risk for dehydration with ensuing loss of electrolytes, leading to sluggishness and impaired physical performance. METHODS: We evaluated an electrolyte and amino acid product containing L-alanine and L-glutamine, as well as select vitamins [B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B12 (cobalamin), and vitamin C (ascorbic acid)]. Subjects (n = 40; four groups, n = 10) were randomized to consume either a placebo packet or one, two, or three packets daily of the test product for 4 weeks with site visits at 0, 2, and 4 weeks. We tested safety and tolerability by analyzing hematological parameters (complete blood counts), metabolic parameters (hepatic, renal, acid-base balance), urinalysis end products, thyroid status [T3 (triiodothyronine), T4 (thyroxine), TSH (thyroid-stimulating hormone)], tolerability (via questionnaire), vital signs, and dietary intake. RESULTS: Statistical analyses displayed ten significant main effects (p < 0.05) with white blood cells, lymphocytes, neutrophils, urinary pH, thyroxine, urination frequency, calcium, calories, fat, and cholesterol. Interactions for time and group (p < 0.05) were observed for MCV, eGFR, potassium, overall tolerability, bloating, and cramping-demonstrating mild GA disturbances. Little to no change of physiological relevance was noted for any outcome variable, regardless of dosing level. CONCLUSIONS: Our results indicate the product was well-tolerated at all dosing levels and no significant adverse changes occurred in any of the test parameters compared to the placebo group, indicating relative safety of ingestion over a 4-week treatment period, at the volumes used, and outside the context of physical stress.

OBJECTIVE: Hyperphosphatemia is a common complication in patients with kidney failure, despite the use of phosphate binders. Vitamin B3, either in the form of niacin or niacinamide (NAM), shows potential as "add-on" treatment to reduce serum phosphate concentrations in this population. NAM seems to lack many of the side effects that are observed with niacin. The aim of this study was to investigate whether NAM is an effective and acceptable treatment in reducing serum phosphate concentrations in patients with kidney failure. METHODS: DiaNia was a double-blind placebo-controlled randomized crossover trial, comparing NAM (250-500 mg/day) to placebo as "add-on" treatment to an individual treatment with approved phosphate binders for 12 weeks in patients receiving hemodialysis. The primary outcome was serum phosphate concentrations, and the secondary outcomes were platelet counts as well as drop-outs due to side effects. Data were analyzed using both per-protocol and intention-to-treat analyses. RESULTS: Mean age of the per-protocol population (n = 26) was 63.6 ± 17.2 years and 53.8% were men. NAM treatment significantly reduced serum phosphate with 0.59 mg/dL (p = .03). Linear mixed-effects models demonstrated superiority of 12 weeks NAM over 12 weeks placebo with a between-treatment difference of 0.77 mg/dL (95% CI 0.010, 1.43; P = .03). Similar results, although not significant, were found in the intention-to-treat population. We found no between-treatment differences in platelet counts and during the NAM treatment we observed 3 drop-outs due to side effects (8.6%). CONCLUSION: NAM is effective in reducing serum phosphate concentrations in patients with kidney failure receiving hemodialysis. In addition, NAM is well-tolerated and seems not to increase the risk of thrombocytopenia. Thus, NAM can be valuable as "add-on" treatment to combat hyperphosphatemia in patients with kidney failure. However, more research in larger populations is needed to confirm this.

Growing evidence suggests that the depletion of plasma NAD+ and glutathione (GSH) may play an important role in the development of metabolic disorders. The administration of Combined Metabolic Activators (CMA), consisting of GSH and NAD+ precursors, has been explored as a promising therapeutic strategy to target multiple altered pathways associated with the pathogenesis of the diseases. Although studies have examined the therapeutic effect of CMA that contains N-acetyl-l-cysteine (NAC) as a metabolic activator, a system-wide comparison of the metabolic response to the administration of CMA with NAC and cysteine remains lacking. In this placebo-controlled study, we studied the acute effect of the CMA administration with different metabolic activators, including NAC or cysteine with/without nicotinamide or flush free niacin, and performed longitudinal untargeted-metabolomics profiling of plasma obtained from 70 well-characterized healthy volunteers. The time-series metabolomics data revealed the metabolic pathways affected after the administration of CMAs showed high similarity between CMA containing nicotinamide and NAC or cysteine as metabolic activators. Our analysis also showed that CMA with cysteine is well-tolerated and safe in healthy individuals throughout the study. Last, our study systematically provided insights into a complex and dynamics landscape involved in amino acid, lipid and nicotinamide metabolism, reflecting the metabolic responses to CMA administration containing different metabolic activators. Crown Copyright © 2023. Published by Elsevier Inc. All rights reserved.

BACKGROUND: Cutaneous lupus erythematosus is an umbrella term for a group of autoimmune connective tissue disorders affecting the skin. Discoid lupus erythematosus (DLE) is the chronic condition and most common form of cutaneous lupus erythematosus. AIMS: Current therapies of DLE are challenging and not completely satisfactory, highly expensive, off-label, or poorly available (like antimalarials due to COVID-19 outbreaks). Nicotinamide, also called niacinamide, is a water-soluble form of vitamin B3 (niacin). Its multiple effects let us think that nicotinamide could be a therapy for lupus-associated skin lesions. METHODS: We performed a prospective randomized double-blind clinical trial on 60 subjects diagnosed with Discoid lupus erythematosus using topical Nicotinamide 2% and 4% preparations in form of cream and gel on skin and scalp lesions. Control group was included using only cream/gel base as placebo control. RESULTS: Obtained data showed that topical Nicotinamide can be used for the treatment of DLE as adjuvant to other treatment regimens with good cosmetic results and minimal side effects. Topical 4% Nicotinamide is superior to 2% preparation in response but associated with a higher incidence of irritation. CONCLUSION: Topical Nicotinamide can be used for the treatment of DLE as an adjuvant to other treatment regimens with good cosmetic results and minimal side effects. Further trials with long-term therapy, follow-up period, and bigger sample sizes are required. © 2023 The Authors. Journal of Cosmetic Dermatology published by Wiley Periodicals LLC.

BACKGROUND: Boosting NAD+ via supplementation with niacin equivalents has been proposed as a potential modality capable of promoting healthy aging and negating age-dependent declines of skeletal muscle mass and function. OBJECTIVES: We investigated the efficacy of NAD+-precursor supplementation (tryptophan, nicotinic acid, and nicotinamide) on skeletal muscle mitochondrial function in physically compromised older adults. METHODS: A randomized, double-blind, controlled trial was conducted in 14 (female/male: 4/10) community-dwelling, older adults with impaired physical function [age, 72.9 ± 4.0 years; BMI, 25.2 ± 2.3 kg/m2]. Participants were supplemented with 207.5 mg niacin equivalents/day [intervention (INT)] and a control product (CON) that did not contain niacin equivalents, each for 32 days. The primary outcomes tested were mitochondrial oxidative capacity and exercise efficiency, analyzed by means of paired Student's t-tests. Secondary outcomes, such as NAD+ concentrations, were analyzed accordingly. RESULTS: Following supplementation, skeletal muscle NAD+ concentrations [7.5 ± 1.9 compared with 7.9 ± 1.6 AU, respectively] in INT compared with CON conditions were not significantly different compared to the control condition, whereas skeletal muscle methyl-nicotinamide levels were significantly higher under NAD+-precursor supplementation [INT, 0.098 ± 0.063 compared with CON, 0.025 ± 0.014; P = 0.001], suggesting an increased NAD+ metabolism. Conversely, neither ADP-stimulated [INT, 82.1 ± 19.0 compared with CON, 84.0 ± 19.2; P = 0.716] nor maximally uncoupled mitochondrial respiration [INT, 103.4 ± 30.7 compared with CON, 108.7 ± 33.4; P = 0.495] improved under NAD+-precursor supplementation, nor did net exercise efficiency during the submaximal cycling test [INT, 20.2 ± 2.77 compared with CON, 20.8 ± 2.88; P = 0.342]. CONCLUSIONS: Our findings are consistent with previous findings on NAD+ efficacy in humans, and we show in community-dwelling, older adults with impaired physical function that NAD+-precursor supplementation through L-tryptophan, nicotinic acid, and nicotinamide does not improve mitochondrial or skeletal muscle function. This study was regis

Nonalcoholic fatty liver disease, which has been rapidly increasing in the world in recent years, is roughly classified into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis. This study was based on our previous reports that stated that the combination treatment of N1-methylnicotinamide (MNA) and hydralazine (HYD) improves fatty liver in NAFL model rats. This finding was attributed to the MNA metabolism inhibition by HYD, which is a strong inhibitor of aldehyde oxidase (AO); this results in an increase in hepatic MNA and improved fatty liver. We hypothesized that orally administered nicotinamide (NAM), which is the precursor of MNA and is a form of niacin, would be efficiently metabolized by nicotinamide N-methyltransferase in the presence of exogenous S-adenosylmethionine (SAM) in NAFL rats. To address this issue, NAFL model rats were orally administered with NAM, SAM, and/or HYD. As a result, liver triglyceride (TG) and lipid droplet levels were barely altered by the administration of NAM, SAM, NAM+SAM, or NAM+HYD. By contrast, the triple combination of NAM+SAM+HYD significantly reduced hepatic TG and lipid droplet levels and significantly increased hepatic MNA levels. These findings indicated that the combination of exogenous SAM with AO inhibitors, such as HYD, has beneficial effects for improving fatty liver with NAM.

PURPOSE: The nicotinamide phosphoribosyltransferase (NAMPT) inhibitor, APO866, has been previously shown to have antileukemic activity in preclinical models, but its cytotoxicity in primary leukemia cells is frequently limited. The success of current antileukemic treatments is reduced by the occurrence of multidrug resistance, which, in turn, is mediated by membrane transport proteins, such as P-glycoprotein-1 (Pgp). Here, we evaluated the antileukemic effects of APO866 in combination with Pgp inhibitors and studied the mechanisms underlying the interaction between these two types of agents. EXPERIMENTAL DESIGN: The effects of APO866 with or without Pgp inhibitors were tested on the viability of leukemia cell lines, primary leukemia cells (AML, n = 6; B-CLL, n = 19), and healthy leukocytes. Intracellular nicotinamide adenine dinucleotide (NAD(+)) and ATP levels, mitochondrial transmembrane potential (ΔΨ(m)), markers of apoptosis and of endoplasmic reticulum (ER) stress were evaluated. RESULTS: The combination of APO866 with Pgp inhibitors resulted in a synergistic cytotoxic effect in leukemia cells, while sparing normal CD34(+) progenitor cells and peripheral blood mononuclear cells. Combining Pgp inhibitors with APO866 led to increased intracellular APO866 levels, compounded NAD(+) and ATP shortage, and induced ΔΨ(m) dissipation. Notably, APO866, Pgp inhibitors and, to a much higher extent, their combination induced ER stress and ER stress inhibition strongly reduced the activity of these treatments. CONCLUSIONS: APO866 and Pgp inhibitors show a strong synergistic cooperation in leukemia cells, including acute myelogenous leukemia (AML) and B-cell chronic lymphocytic leukemia (B-CLL) samples. Further evaluations of the combination of these agents in clinical setting should be considered. ©2015 American Association for Cancer Research.

Two compounds are known as the vitamin niacIn: nicotinic acid (NiA) and nicotinamide (Nam). The physiological functions and metabolic fates of NiA and Nam are identical, but differ when pharmacological doses are administered. Our study aimed to investigate the metabolic interactions between NiA and Nam when their pharmacological doses were administered together. We measured seven major niacin catabolites, including NiA, Nam, N(1)-methylnicotinamide (MNA), N(1)-methyl-2-pyridone-5-carboxamide (2-Py), N(1)-methyl-4-pyridone-3-carboxamide (4-Py), Nam N-oxide, and nicotinuric acid (NuA). Under physiological conditions, niacin is chiefly catabolized to 4-Py via MNA. However, this was not the primary pathway when rats were fed a diet containing excess niacin. When rats were fed a diet containing excess NiA, NuA was the major catabolite, and on being fed a diet containing excess Nam, MNA was the major catabolite. When rats were fed a diet containing an excess of both NiA and Nam, MNA and NuA were the major catabolites. The metabolic fates of excess NiA and Nam did not mutually interfere. Therefore, the administration of NiA and Nam together may be better than the administration of NiA or Nam alone because different pharmacological effects are expected.

Nicotinamide adenine dinucleotide (NAD) is a metabolite essential for cell survival and generated de novo from tryptophan or recycled from nicotinamide (NAM) through the nicotinamide phosphoribosyltransferase (NAMPT)-dependent salvage pathway. Alternatively, nicotinic acid (NA) is metabolized to NAD through the nicotinic acid phosphoribosyltransferase domain containing 1 (NAPRT1)-dependent salvage pathway. Tumor cells are more reliant on the NAMPT salvage pathway making this enzyme an attractive therapeutic target. Moreover, the therapeutic index of NAMPT inhibitors may be increased by in NAPRT-deficient tumors by NA supplementation as normal tissues may regenerate NAD through NAPRT1. To confirm the latter, we tested novel NAMPT inhibitors, GNE-617 and GNE-618, in cell culture- and patient-derived tumor models. While NA did not protect NAPRT1-deficient tumor cell lines from NAMPT inhibition in vitro, it rescued efficacy of GNE-617 and GNE-618 in cell culture- and patient-derived tumor xenografts in vivo. NA co-treatment increased NAD and NAM levels in NAPRT1-deficient tumors to levels that sustained growth in vivo. Furthermore, NAM co-administration with GNE-617 led to increased tumor NAD levels and rescued in vivo efficacy as well. Importantly, tumor xenografts remained NAPRT1-deficient in the presence of NA, indicating that the NAPRT1-dependent pathway is not reactivated. Protection of NAPRT1-deficient tumors in vivo may be due to increased circulating levels of metabolites generated by mouse liver, in response to NA or through competitive reactivation of NAMPT by NAM. Our results have important implications for the development of NAMPT inhibitors when considering NA co-treatment as a rescue strategy.

Extended-release (ER) niacin (nicotinic acid)/laropiprant is a once-daily fixed-dose combination tablet that has been evaluated (with or without an HMG-CoA reductase inhibitor [statin]) in the treatment of adults with dyslipidaemia or primary hypercholesterolaemia. Niacin (vitamin B3) is a lipid-modifying drug and laropiprant is an anti-flushing agent, which reduces flushing induced by niacin. In a randomized, double-blind, placebo-controlled, multicentre, 24-week trial, a significant (p < 0.001) reduction (18.4%) in plasma low-density lipoprotein cholesterol (LDL-C) levels (primary endpoint) was achieved with ER niacin/laropiprant 2000 mg/40 mg once daily (after an initial 4-week 1000 mg/20 mg once-daily regimen) compared with placebo (weeks 12-24) in adults with primary hypercholesterolaemia or mixed dyslipidaemia. ER niacin/laropiprant 2000 mg/40 mg plus simvastatin 20 mg or 40 mg once daily (after an initial 4-week lower-dose regimen) produced significant (p < 0.05) improvements, from baseline, in LDL-C levels (primary endpoint) compared with once-daily ER niacin/laropiprant 2000 mg/40 mg or simvastatin alone at week 12 in a randomized, double-blind, multicentre, factorial trial in adults with primary hypercholesterolaemia or mixed dyslipidaemia. The incidence and intensity of flushing (an efficacy endpoint) were significantly (p < 0.05) reduced with ER niacin/laropiprant compared with ER niacin in randomized trials. ER niacin/laropiprant, alone or in combination with a statin, was generally well tolerated for up to 24 weeks by adults with dyslipidaemia or primary hyercholesterolaemia.

21. Gastroenterol Nurs. 1997 Mar-Apr;20(2):63-4. Common vitamin B complex agents and folic acid: Part III. Niacin (nicotinic acid) (Niacinamide, Nia-Bid, Niac, Niacels, Nico-400, Nicobid, Nicolar, Nicotinex, Slo-Niacin, Span-Niacin, Tega-Span). [No authors listed]

An analytical system comprising a bacterium and a protozoan was used to pinpoint the metabolic lesion whereby chlorhexidine (CLX) produced cell death. Nicotinic acid but not nicotinamide annulled the biocidal action of CLX. The results suggest that CLX may not permit bioconversion of nicotinamide to nicotinic acid to annul the growth inhibition induced by CLX.

The effect of zinc supplementation on the metabolism of tryptophan conversion to niacin was studied in 14 alcoholic patients with pellagra and in 7 male control subjects aged 21-45 y. The pellagrins received chemically defined diets based on crystalline amino acids through an enteral tube for 7 d. Patients were divided into two groups (A and B), both receiving a diet from which tryptophan, Zn, and niacin were excluded. Patients in group B, however, received 220 mg Zn sulfate orally. Upon admission the pellagra patients had low plasma Zn levels and low urinary excretion values of N'methylnicotinamide (N'MN) and N'methyl-2-pyridone-5-carboxamide (2-PYR) in relation to the control subjects (p less than 0.01). During the experimental period there was an increase in plasma Zn levels (p less than 0.005) and in urinary N'MN (p less than 0.05) and 2-PYR (p less than 0.05) excretion in the patients receiving Zn supplementation (group B). These results suggest that Zn interacts with niacin metabolism in alcoholic patients with pellagra through a probable mediation by vitamin B-6.

24. Vestn Dermatol Venerol. 1989;(12):20-3. [The effect of nicotinamide and nicotinic and ascorbic acids on the penicillin concentration in the blood serum and tissues of rabbits]. [Article in Russian] Bednova VN, Rotanov SV, Navolotskaia TI, Milonova TI, Orlina EA. Measurements of penicillin concentrations in the blood sera and tissues of rabbits have revealed a reduction of this antibiotic levels as the doses of injected ascorbic acid grew. A combination of benzylpenicillin with ascorbic and nicotinic acids improved penicillin penetration into experimental animals' tissues.

25. Arch Anat Microsc Morphol Exp. 1976;65(1):1-6. [Prevention of abnormalities induced by 2 organophosphate insecticides (parathion and bidrin) in quail embryos]. [Article in French] Meiniel R. When Quail embryos, injected with bidrin at the unincubated stage, are treated with nicotinamide, beak and leg abnormalities are prevented, but niacin has no beneficial effect on the axial deformities caused by both parathion and bidrin. In contrast, vertebral defects are greatly reduced by giving pralidoxim, an antidote known and used in organophosphorus intoxications. But this compound has no effect on beak and leg damage caused by bidrin. Two other cholinesterase reactivators, diacetylmonoxime and monoisonitrosoacetone have any effect on organophosphorus abnormalities and have no antiteratogenic action either on the beak and legs or on the vertebral column. From these observations the multiple causes of teratogenic effects induced by organophosphorus compounds are evident. Both aspects of teratogenesis, one related to the nicotinamide level, and the other related to the physiology of the cholinergic system are discussed.

BACKGROUND: Dietary patterns (DPs) provide a comprehensive picture of the foods consumed by an individual. OBJECTIVES: Using 12-y follow-up data from the Korean Genome Epidemiology Study (KoGES), we determined the associations of DPs with incident cardiovascular disease (CVD) using reduced rank regression (RRR). METHODS: This study analyzed the data of 7354 CVD-free subjects aged 40-69 y drawn from the community-based KoGES cohort. Based on the daily intake of 26 food groups at baseline, we identified DPs based on retinol, vitamin B-2 (riboflavin), and vitamin B-3 (niacin) intakes using RRR. The effects of the DPs on incident CVD were assessed using HRs with 95% CIs. Furthermore, using a marginal structural model, the association between DPs and incident CVD was evaluated after adjusting for time-varying confounders. RESULTS: The incidence of CVD during the follow-up period was 3.7 per 1000 person-years (n = 274). The identified DP accounted for 28.99% of the variation in the response variables (i.e., the intake amounts of all 3 nutrients) and was characterized by high intakes of eggs, fish, milk, and dairy products. The effect of DP quintile on incident CVD differed by sex (Pinteraction = 0.03); the highest DP quintile was associated with a protective effect against the development of CVD in women (HR: 0.44; 95% CI: 0.22, 0.89), but not in men (HR: 1.57; 95% CI: 0.82, 3.00), compared with the lowest quintile. Even after adjusting for time-dependent variables, the effect of DP on incident CVD was significant in women (HR: 0.43; 95% CI: 0.22, 0.84), but not in men (HR: 1.49; 95% CI: 0.71, 3.10). CONCLUSIONS: In this study, we identified DPs related to CVD, and a DP characterized by high intakes of eggs, fish, milk, and dairy products protected against incident CVD in women.

Nicotinamide adenine dinucleotide (NAD⁺) declines with age, motivating "NAD⁺-boosting" strategies ranging from lifestyle interventions to supplementation with NAD⁺ precursors (e.g., nicotinamide riboside [NR], nicotinamide mononucleotide [NMN]) and, in some wellness settings, parenteral NAD⁺ administration. We conducted a PRISMA-guided systematic review of peer-reviewed human and rodent intervention studies (January 2010-October 2025) evaluating NAD-related compounds administered orally or parenterally. We identified 113 eligible studies: 33 human intervention studies (28 randomized; 5 nonrandomized) and 80 rodent studies. In rodent models, NAD⁺ augmentation was frequently associated with improvements in metabolic, mitochondrial, inflammatory, and functional outcomes, although effects varied across models and endpoints. In humans, oral NR and NMN consistently demonstrated biochemical target engagement (circulating (plasma/whole blood) or cellular (e.g., PBMC) NAD-related metabolites) and were generally well tolerated over weeks to months; however, effects on functional, metabolic, vascular, and other healthspan-relevant outcomes were heterogeneous and often null or endpoint-specific. No eligible outcomes trials evaluated intravenous or intramuscular NAD⁺ itself for anti-aging or wellness indications. One nonrandomized intravenous NMN study met inclusion criteria and primarily contributed short-term safety and biomarker information. An intravenous NAD⁺ pharmacokinetic pilot lacking eligible clinical outcomes was identified as contextual evidence only. Overall, NAD⁺ augmentation shows clear biological activity, but clinical effectiveness for anti-aging or wellness outcomes remains inconclusive. Larger, well-designed randomized trials with longer follow-up and prespecified clinically meaningful endpoints are needed, particularly for parenteral approaches.

Nicotinamide(NAM) and niacin are forms of vitamin B3 commonly utilised as health supplements. Recent studies highlight its potential effects in glaucoma, leading to increasing use by patients. However, there are no studies on the adverse effects (AEs) of nicotinamide or niacin use in ophthalmology. We examined the incidence of clinically important AEs of oral NAM/niacin in humans and subsequent management strategies. A systematic search of reviews or meta-analyses was undertaken using pre-defined search criteria on PubMed with inclusion were agreed on by two independent researchers. Risk of bias assessment was performed using the ROBIS checklist.14 reviews were included, revealing the following: (1) Oral niacin and NAM were associated with a range of AEs including GI upset, liver dysfunction, flushing/vasodilatory effects, skin rash and fatigue. (2) Oral NAM is associated with a lower incidence of AEs than niacin. (3) AEs are more common with higher doses of oral NAM/niacin, and limits tolerability depending on co-morbid status (e.g.: renal dysfunction). (4) Only 6 reviews described discontinuation or reduction in dosage for AEs. (5) The majority of AEs diminished or resolved with reduction or discontinuation of oral niacin/NAM. AEs are diverse and dose-dependent, however, there remains a paucity of literature examining its side effects in a systematic manner. Standardised dosing, outcome measures and adverse effects should be utilised in further research and a surveillance system for reporting adverse effects. Regular clinical monitoring of AEs may not be indicated for doses of oral NAM under 1500 mg/day. © 2025. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.

BACKGROUND: Glaucoma is a progressive optic neuropathy, characterised by a complex pathophysiology, with mitochondrial dysfunction playing a significant role in the cellular damage and apoptosis of ganglion cells. Niacin is a precursor to several molecules acting as coenzymes in the mitochondrial production of ATP, in DNA repair and in the reduction of reactive oxygen species. The objective of this systematic review is to assess the impact of daily niacin intake on glaucoma. METHODS: Case-control and cohort studies regarding niacin and glaucoma, indexed in PubMed, Web of Science, Cochrane and Scopus, were included. Other study methodologies, studies regarding niacin in other ocular disease or other nutrients in glaucoma were excluded. Bias was assessed using the Newcastle-Ottawa Scale. The study protocol was registered in the PROSPERO database (no. CRD42024578889). RESULTS: Five case-control studies were included. In the pooled analysis, a significantly higher proportion of patients with high niacin consumption was found in the group without glaucoma compared to those with glaucoma as defined by ISGEO criteria (p-value < 0.00001; OR = 0.66, 95% CI 0.55-0.79) or as defined by retinal imaging (p-value = 0.02; OR = 0.63, 95% CI 0.43-0.94). CONCLUSIONS: Daily dietary intake of niacin is significantly lower in patients with glaucoma compared to the general population. Given different average daily intakes of niacin in these populations, different glaucoma definitions and several confounding variables which weaken the associations, large sample, standardised randomised controlled trials are needed to confirm the potential benefits of niacin in glaucoma.

Sexual dysfunction can adversely affect the quality of life, self-confidence, and interpersonal relationships. Some studies reported a relationship between vitamin supplementation and sexual health. This systematic review aimed to evaluate the effect of vitamins on female and male sexual function. All relevant English and Persian articles published in English databases (Medline, Scopus, Cochrane Library, Web of Sciences, Psycho-Info, and Proquest) and Farsi databases (SID and Magiran) until July 2020 were searched. The Cochrane Handbook for Systematic Reviews of Interventions was used for assessing the risks of bias. A total of 11 randomized controlled trials (RCTs) on 337 women, 472 men, and 35 couples were included. One study reported that vitamin D 300000 IU supplement administrated twice through intramuscular injection (at the beginning and after four weeks) had a significant effect on female sexual function (p<0.05), whereas another study showed that vitamin D 2000 IU supplement for six months did not have any significant effect on female sexual function (p>0.05). A study reported the significant effect of niacin (vitamin B3) 1500 mg daily for 12 weeks on erectile function (p=0.004). The results showed that vitamins A, C, and E had no significant effect on male and female sexual function. The conduction of trials with long-term interventions is recommended to reach a more definitive conclusion about the effect of vitamins on sexual function.

BACKGROUND: Vegan diets, where animal- and all their by-products are excluded from the diet, have gained popularity, especially in the last decade. However, the evaluation of this type of diet has not been well addressed in the scientific literature. This study aimed to investigate the adequacy of vegan diets in European populations and of their macro- and micronutrient intakes compared to World Health Organization recommendations. METHODS: A systematic search in PubMed, Web of Science, IBSS, Cochrane library and Google Scholar was conducted and 48 studies (12 cohorts and 36 cross-sectional) were included. RESULTS: Regarding macronutrients, vegan diets are lower in protein intake compared with all other diet types. Veganism is also associated with low intake of vitamins B2, Niacin (B3), B12, D, iodine, zinc, calcium, potassium, selenium. Vitamin B12 intake among vegans is significantly lower (0.24-0.49 μg, recommendations are 2.4 μg) and calcium intake in the majority of vegans was below recommendations (750 mg/d). No significant differences in fat intake were observed. Vegan diets are not related to deficiencies in vitamins A, B1, Β6, C, E, iron, phosphorus, magnesium, copper and folate and have a low glycemic load. CONCLUSIONS: Following a vegan diet may result in deficiencies in micronutrients (vitamin B12, zinc, calcium and selenium) which should not be disregarded. However, low micro- and macronutrient intakes are not always associated with health impairments. Individuals who consume a vegan diet should be aware of the risk of potential dietary deficiencies.

PURPOSE: Clinical trials have shown that niacin and its analog, niacinamide, significantly reduce serum phosphate in patients undergoing dialysis. This review aimed to assess the benefits and harm of niacin and niacinamide in renal dialysis patients. METHODS: PubMed, EMBASE, and Cochrane Library were searched, without language limitation, randomized controlled trials (RCTs). Standard methods, consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, were used. Reviewer Manager software, version 5.2, was used for meta-analysis. RESULTS: Five RCTs with a sample size of 230 patients were included. The meta-analysis showed that niacin and niacinamide significantly decreased serum phosphorus levels [weight mean difference (WMD) -0.88; 95 % confidence interval (CI) -1.19 to -0.57] as well as the calcium × phosphorus product (Ca × P) (WMD -9.15; 95 % CI -13.23 to -5.08), and increased high-density lipoprotein (HDL) levels (WMD 9.30; 95 % CI 5.86-12.74) in renal dialysis patients. Niacin significantly increased the risk of flushing [relative risk (RR) 33; 95 % CI 4.71-232.12] in these patients, while the risk of thrombocytopenia was significantly increased in the niacinamide group (RR 2.82; 95 % CI 1.14-6.94). However, sensitivity analysis showed that our finding regarding thrombocytopenia should be regarded with a low degree of certainty. CONCLUSION: Niacin and its analog effectively improved phosphorus metabolism in renal dialysis patients. However, niacin can cause flushing and niacinamide probably cause thrombocytopenia. Further larger sample size and well-designed RCTs are needed.

BACKGROUND: The risk of vitamin B-3 (niacin) deficiency is increased if maize is consumed without improving bioavailability during food preparation and with limited consumption of niacin-rich foods. OBJECTIVES: We assessed human-milk vitamin B-3 concentrations and their relationship to child outcomes as a secondary analysis of a randomized controlled trial of nicotinamide supplementation to lactating mothers in rural Tanzania. METHODS: The Early Life Interventions for Childhood Growth and Development in Tanzania study, conducted in Haydom, Tanzania, randomly assigned lactating females to supplemental nicotinamide (250 mg/d compared with placebo) from study entry (infant age <2 wk) until 6 mo. Among 1173 mother/child dyads, human-milk nicotinamide and B3 vitamer concentrations at lactation months 1 and 5 were compared with international reference limits (fifth and 95th percentile) from the recent Mothers, Infants and Lactation Quality study, and child anthropometry and cognitive development [Malawi Developmental Assessment Tool (MDAT)] relationships were assessed. RESULTS: The proportion of human-milk total vitamin B-3 concentrations below the lower reference limit increased over time in both those without and with nicotinamide supplementation (2.9% compared with 0.5% ≤0.720 mg/L at 1 mo; 28.8% compared with 9.9% ≤0.549 mg/L at 5 mo). Maternal nicotinamide supplementation was associated with many participants having human-milk total vitamin B-3 concentrations exceeding the upper reference limit (72.9% ≥3.284 mg/L at 1 mo; 50.7% ≥2.760 mg/L at 5 mo), and a sustained higher median concentration with supplementation compared with placebo (by 291% at month 1 and 281% at month 5). No associations were observed between human-milk total vitamin B-3 or vitamer concentrations and child weight, height, or head circumference ≤18 mo or with MDAT scores at 18 mo. CONCLUSIONS: Without maternal nicotinamide supplementation, lactating females had a greater prevalence of human-milk total vitamin B-3 concentrations below the fifth percentile reference limit. Although supplementation was associated with greater total vitamin B-3 and vitamer concentrations, there was no association

Despite the availability of antiseizure medications (ASMs), approximately one-third of patients with epilepsy remain refractory to treatment. Evidence suggests that the gut microbiota modulates central nervous system function through neuroimmune and metabolic pathways. We characterized the fecal microbiome of patients with epilepsy and autoimmune encephalitis (AE) using 16S rRNA sequencing. Ninety-six participants from a tertiary hospital in Brazil were included: mesial temporal lobe epilepsy (MTLE; n = 38), genetic generalized epilepsy (GGE; n = 11), AE (n = 10), and healthy controls (n = 37). Microbial community composition differed between treatment-responsive and refractory patients. Compared with responsive individuals (n = 16), refractory patients (n = 43) showed lower relative abundances of Agathobaculum, Bacteroides, Bilophila, and Coprobacter, and higher abundance of Guopingia. Dietary fiber intake was negatively associated with Enterocloster and Frisingicoccus. Riboflavin (vitamin B2) and niacin (vitamin B3) were positively associated with Schaalia and Hominimerdicola, respectively. Functional predictions indicated that valproic acid use and treatment responsiveness were associated with increased microbial potential for GABA synthesis and tryptophan degradation, and reduced potential for dopamine and histamine degradation. These findings link the gut microbiome to epilepsy subtype and treatment response. © 2026 The Author(s). Published with license by Taylor & Francis Group, LLC.

35. Adv Nutr. 2026 Jun;17(6):100646. doi: 10.1016/j.advnut.2026.100646. Epub 2026 May 8. Nutrition Information Briefs - Niacin. Meyer-Ficca ML(1), Chini CC(2). Author information: (1)Department of Veterinary Clinical and Life Sciences, College of Veterinary Medicine, Utah State University, Logan, UT, United States. Electronic address: [email protected]. (2)Department of Anesthesiology and Perioperative Medicine, Metabolism and Molecular Nutrition Laboratory, Kogod Center on Aging, Mayo Clinic College of Medicine, Jacksonville, FL, United States. DOI: 10.1016/j.advnut.2026.100646 PMCID: PMC13233546 PMID: 42107767

Erratum in Biochem Pharmacol. 2026 Aug;250(Pt 1):118070. doi: 10.1016/j.bcp.2026.118070. Skeletal muscle injury is prevalent in clinical practice and sports medicine, and efficient regeneration is crucial for restoring motor function. Niacin (vitamin B3, NIA), a water-soluble essential nutrient and key precursor of nicotinamide adenine dinucleotide (NAD + ), regulates muscle metabolism and mitochondrial function, but its role and underlying mechanisms in skeletal muscle injury repair remain unclear. In this study, a mouse model of acute skeletal muscle injury was established via intramuscular injection of bupivacaine hydrochloride, and C2C

Anemia is a public health issue affecting people of all ages worldwide. 43% of children under five in Egypt are suffering from anemia. Hemolytic anemia (HA), characterized by the premature destruction of red blood cells, is often associated with oxidative stress. Phenylhydrazine (PHZ) is a chemical substance frequently used to induce HA in experimental animal models. Studies indicate that niacin (nicotinic acid) activates antioxidant pathways through nuclear factor erythroid 2-related factor 2 (Nrf2). This study aimed to evaluate the antianemic effects of niacin in PHZ-induced hemolytic anemia in rats. Twenty-four rats were divided into four groups (n=6). The control group received saline for two days, then 5% CMC. The anemia group received PHZ (40 mg/kg/day, i.p.) for two days, followed by 5% CMC. The low- and high-dose niacin groups received PHZ for two days, then niacin (100 or 360 mg/kg/day, orally) for six day

The objective of this study was to (1) investigate the impact of commonly used heat treatment methods - water bath cooking (WBC), convection oven roasting (OCR), grilling (G), and pan frying (PF) - on the concentrations and retention of various forms of selected B vitamins (B1, B2, B3, B5, B6, and B12) in goose breast muscle, and (2) assess the extent to which a 100 g portion of goose meat, both with and without skin, contributes to meeting the Nutrient Reference Values-Requirements (NRV-R) for these vitamins in the adults. The material used in the study comprised 36 breast muscles of 17-week-old White Koluda® geese. The contents of B vitamins were determined using liquid chromatography. Significantly lower thermal losses were found in skinless meat (P ≤ 0.05). This meat co

Acute myeloid leukaemia (AML) exhibits profound metabolic plasticity that enables leukaemic cells to survive environmental stress, nutrient limitation, and therapeutic pressure, ultimately driving disease persistence and relapse. While genetic and epigenetic alterations have guided risk stratification and therapeutic development, accumulating evidence indicates that nutrient-dependent metabolic rewiring represents a critical and targetable vulnerability in AML. Nicotinamide adenine dinucleotide (NAD) is a central metabolic cofactor whose intracellular availability is tightly linked to dietary intake of its precursors, including tryptophan, niacin (vitamin B3), nicotinamide, and nicotinamide riboside. NAD sup

INTRODUCTION: Hypervirulent Klebsiella pneumoniae (hvKp) is an important pathogen causing central nervous system infections, including meningitis; however, the mechanisms by which it disrupts the blood-brain barrier remain unclear. Niacin, a vitamin B3 compound related to NAD+ metabolism, has the potential to regulate redox homeostasis. This study aimed to investigate the mechanism of hvKp-induced injury in human cerebral microvascular endothelial cell (HCMEC) and to evaluate the protective effects of niacin. METHODS: A GFP-labeled hvKp ATCC 43816 strain was used to establish an HCMEC infection model, and an hvKp mouse meningitis model was also constructed. Live-cell imaging was performed to monitor infection dynamics. Flow cytometry was used to assess infection rate, reactive oxygen species (ROS) levels, and

Early-onset progressive encephalopathy with brain edema and/or leukoencephalopathy-2 (PEBEL2) is a rare autosomal recessive neurometabolic disorder caused by pathogenic variants in NAXD, in which febrile illness or infection triggers rapid clinical deterioration. We describe nine new cases that expand the clinical and molecular spectrum. Four children showed the typical presentation of severe neurological decline following fever or illness and carried variants affecting the enzyme domain. Four cases presented with illness-triggered cardiac dysfunction associated with variants in the mitochondrial targeting sequence. One case showed severe prenatal neurodegeneration resulting in stillbirth. In two patients, disease onset followed COVID-19 infection. Functional analysis of five missense variants demonstrated impaired NAXD protein solubility, reduced NADHX dehydratase activity and/or decreased thermostability. Patient fibroblasts confirmed accumulation of damaged cofactors (S-, R- and cyclic NADHX) and reduced NAXD protein levels. Comparative proteomic analysis revealed distinct molecular profiles in atypical cardiac and prenatal cases compared with typical neurological presentations. Four patients received high-dose niacin (vitamin B3) and survived repeated febrile episodes. These findings support early recognition and suggest that niacin therapy may improve outcomes across the clinical spectrum of PEBEL2. © 2026 The Author(s). Journal of Inherited Metabolic Disease published by John Wiley & Sons Ltd on behalf of SSIEM.

Yarrowia lipolytica is a food-compatible yeast with strong potential for sustainable B-vitamin enrichment of functional food ingredients. This study evaluated the effects of glucose, xylose, mixed, and lignocellulosic sugars, as well as diverse nitrogen sources, on yeast growth and B-vitamin yields in controlled fermentations. Glucose with yeast extract led to the highest biomass and intracellular accumulation of thiamine (B1), niacin (B3), and pyridoxine (B6), while mixed sugars supported maximal

Pellagra is a nutritional deficiency caused by the inadequate intake or metabolism of niacin (vitamin B3) and its precursor tryptophan. While pellagra is now rare in developed countries, individuals with eating disorders such as anorexia nervosa or chronic alcoholism remain at risk of developing this condition. We report a fatal case of pellagra in a woman with anorexia nervosa. Autopsy revealed severe emaciation, Casal's necklace, and additional cutaneous findings, including Russell's sign. Histopathological examination of the neck lesion revealed characteristic psoriasiform changes. Postmortem serum analysis revealed a markedly reduced tryptophan concentration (16.1 nmol/mL; reference range: 40.9-68 nmol/mL), consistent with the diagnosis of pellagra. This case highlights the diagnostic importance of integrated histopathology, cutaneous findings, and postmortem serum amino acid profiling in identifying fatal nutritional deficiencies. Furthermore, it emphasizes the need to consider pellagra in at-risk populations, even in modern forensic settings. © 2026. The Author(s).

Parkinson's disease (PD) therapy remains limited by complications of the levodopa regimen, highlighting the need for novel therapeutic strategies to modulate dopaminergic signaling. Melanostatin (MIF-1) has attracted attention as a privileged scaffold for dopamine D2 receptor (D2R) modulation due to its intrinsic positive allosteric modulatory activity, although improved potency and drug-like properties are required for translation. In this work, nicotinic acid (Nic), a vitamer of vitamin B3, was employed as a proline (Pro) bioisostere, generating 12 vitamin B3-MIF-1 hybrids. Nicotinoyl-l-leucylglycinamide (6c) emerged as a lead compound, promoting a 5.11-fold enhancement of dopamine potency at 0.01 nM and displaying neuroprotective activity at 50-100 μM in dopaminergic-differentiated SH-SY5Y cells. Additionally, Pro-to-Nic substitution showed no cytotoxicity in HepG2, reduced P-glycoprotein-mediated efflux, and preserved β-turn conformational propensity, supporting improved oral drug-like properties. Collectively, these findings identify 6c as a dual-acting lead and establish Nic as a privileged Pro surrogate for next-generation MIF-1-based PD therapeutics.

A rapid method for quantifying the niacin metabolite 1-methylnicotinamide (1-MNA) in human blood is required to address the limitations of existing low-throughput techniques such as mass spectrometry. In previous studies, we demonstrated that supramolecular pillar[6]arenes (P6As) bearing either carboxylate groups (P6AC) or sulfonate groups (P6AS) functioned as "turn-off" fluorescent sensors for 1-MNA detection in urine by photoinduced electron transfer (PET). However, because the concentration of 1-MNA in blood is very low, PET-based detection in aqueous solutions was insufficient for reliable quantification on its own. Here, we report that phosphonate-functionalized P6A (P6AP) in 90% acetonitrile formed aggregates with columnar morphology, which was associated with markedly enhanced detection sensitivity for 1-MNA. Under these conditions, aggregation-induced emission (AIE) resulted in increases in the fluorescence intensity, photoluminescence quantum yield, and photoluminescence lifetime. The addition of 1-MNA suppressed the formation of columnar aggregates of P6AP, and this was accompanied by decreases in the fluorescence intensity, photoluminescence quantum yield, and photoluminescence lifetime. This solvation-dependent fluorescence response substantially improved the detection sensitivity for 1-MNA, enabling its detection in human blood. By contrast, in 80% acetonitrile, P6AP showed AIE but did not exhibit similar columnar aggregates or increase the sensitivity. Overall, the aggregation-state-associated enhancement of the fluorescence response provides a functional framework that enhances fluorescence-based detection and represents a promising platform for extension to a broad range of biologically relevant analytes.

Crystal engineering through co-crystallisation offers a robust strategy for modulating the physicochemical properties and bioavailability of poorly soluble active pharmaceutical ingredients. A thoughtful selection of GRAS status co-formers is critical, as their molecular interactions govern the stability and solubility behaviour of the resulting solid-state architecture. Recently, the integration of nutraceuticals as co-formers has emerged as a promising, safe, and cost-effective approach within crystal engineering. Factors such as the type of functional group for hydrogen bonding, pKa, physicochemical compatibility, solubility, and molecular size need to be considered during co-crystal formation. This review provides a comprehensive summarisation of co-crystals synthesised using nicotinic acid, nicotinamide and asc

OBJECTIVE: There is increasing evidence that B-vitamins may be important for open-angle glaucoma (OAG) prevention due to their roles in neuroprotection, vascular health, and the regulation of homocysteine metabolism, which may influence optic nerve integrity and intraocular pressure (IOP). Therefore, we examined the association between dietary intake of B-vitamins and incident OAG (iOAG). DESIGN: We used data from the Rotterdam Study, a prospective, population-based cohort study in the Netherlands. PARTICIPANTS: We included participants who were free of OAG at baseline, had at least 1 ophthalmic follow-up, and complete data on dietary intake. Among 6742 participants (mean [standard deviation]; age, 62.4 [7.4] years; 58.2% female), 162 developed iOAG. METHODS: The associations between energy-adjusted dietary intake of B-vitamins and iOAG, IOP, retinal nerve fiber layer (RNFL) thickness, and ganglion cell layer (GCL) thickness were assessed using multivariable logistic and linear regression analyses, respectively. All analyses were adjusted for at least age, sex, caloric intake, diet quality, and follow-up time. MAIN OUTCOME MEASURES: The primary outcome was iOAG. Secondary outcomes included IOP, RNFL thickness, and GCL thickness. RESULTS: Dietary intakes of niacin (vitamin B3; odds ratio [OR] with corresponding 95% confidence interval [CI]: 0.94 [0.90-0.98] per mg/d) and cobalamin (vitamin B12; OR [95%CI]: 0.90 [0.83-0.97] per µg/d) were significantly associated with decreased iOAG. Participants with the highest niacin intake (Q5, mean crude intake: 23.27 mg/d) had a significantly lower risk of iOAG (OR [95%CI]: 0.43 [0.21-0.86], p-trend=0.02) compared to those with the lowest intake (Q1, mean crude intake: 9.98 mg/d). A similar association was observed for cobalamin (Q5 [mean crude intake: 10.47 µg/d] vs. Q1 [mean crude intake: 0.19 µg/d], OR [95%CI]: 0.25 [0.12-0.52], p-trend<0.001). Moreover, there was a significant trend towards a lower IOP with higher niacin (p-trend=0.04) and cobalamin (p-trend=0.03) intake. Additionally, cobalamin intake was associated with increased GCL thickness (Beta [95%CI]: 0.01 [0.00-0.03] µg/d; p-trend=0.002). Other B-vitamins were

Pellagra's clinical presentation, etiological factors, and treatment in the early 21st century remain underexplored. This study aimed to update the understanding of pellagra's clinical and etiological aspects with a reappraisal of its treatment and prevention. We searched PubMed and Scopus up to January 9, 2023, to identify relevant studies. The reference lists of all included articles were also carefully screened to identify any additional studies. We included case reports, case series, and case-control studies documenting confirmed cases of pellagra between 2000 and 2023. The review protocol was registered with PROSPERO (CRD42022381416). The search identified 918 studies, of which 133 met the inclusion criteria, comprising 1212 pellagra cases. Cutaneous manifestations were the most common (98.63%), followed by gastrointestinal (59.4%) and neurological (54.2%) signs. Complete symptom resolution occurred on average within 27.42 days of vitamin B3 supplementation. Dietary deficiency remained the predominant cause of pellagra (85%), and it was particularly common in populations af

Dibutyl phthalate (DBP) is a common plasticizer widely used in industrial and medical applications. DBP can cause damage to the female reproductive system due to its estrogen-like effects. However, the mechanisms of DBP toxicity on oocytes and the potential for effective intervention have not been investigated. In this study, porcine oocytes were exposed to different concentrations of DBP, and 600 μM DBP exposure in vitro significantly affected cumulus cell expansion, polar body expulsion, and cytoskeleton formation. Further experiments showed that DBP exposure affects embryonic developmental competence. In addition, DBP exposure led to mitochondrial dysfunction, which was reflected by a decrease in

Purpose To quantify seven dietary vitamins and estimate their mean daily intakes and major food sources among Cuban adults through the country's first Total Diet Study.Methods Standardized 24-hour dietary recalls were collected from 450 adults across Western, Central, and Eastern Cuba between October 2020 and March 2021. Foods were classified into 16 groups, prepared as consumed, homogenized, and analyzed using validated high-performance liquid chromatography with ultraviolet and fluorescence detection. Vitamin concentrations were combined with mean food consumption to estimate daily intakes, which were compared with nutritional reference values.Results Estimated mean daily intakes were 831 µg retinol equivalents for vitamin A, 6.8 mg α-tocopherol equivalents for vitamin E, 1.6 mg thiamine, 1.8 mg riboflavin, 32 mg niacin equivalents, 2.7 mg pyridoxine, and 220 µg dietary folate equivalents. Mean intakes of thiamine, riboflavin, niacin, and pyridoxine exceeded the adult reference values used in the study, whereas vitamin E and folate reached 68% and 55% of their respective benchmarks. Dairy products, vegetables, fruits, and fish were major vitamin A sources; meats and legumes contributed substantially to thiamine intake, and vegetables and legumes were the leading folate sources.Conclusion The reported mean intake estimates identify vitamin E and folate as priorities for dietary improvement in Cuba. Promoting nutrient-rich foods and evaluating selective fortification could help address these gaps. These population mean estimates do not establish individual nutritional adequacy or deficiency prevalence; further assessment of usual intake distributions and nutritional biomarkers is warranted. © 2026. Springer-Verlag GmbH Germany, part of Springer Nature.

Toxoplasma gondii infection remodels the gut microbiome, yet its impact on microbial vitamin biosynthetic potential and host redox metabolism remains unclear. Here, we integrated mouse gut metagenomes with publicly available metagenome-assembled genomes (MAGs) to construct a genome-resolved atlas of B-vitamin and vitamin K2 biosynthesis. From 45,697 MAGs, we curated 4,771 representative genomes, of which 2,682 met high-quality criteria (completeness ≥90%, contamin

The microbiota is being increasingly recognized for its ability to regulate host physiology through the production of small bioactive molecules. However, how host-derived nutrients are metabolically transformed by root-associated microbes to influence plant immunity remains poorly understood. Here, we show that vitamin B3 (VB3; niacin) secreted by plant roots shapes the assembly of a functionally specialized root microbiota, which, in turn, metabolizes VB3 into an immune-active signal that enhances plant disease resistance. VB3 secretion selectively increases the abundance of root-associated bacteria harboring a conserved nic biosynthetic gene cluster (BGC), which enables the conversion of VB3 into 6-hydroxynicotinate (6-OHNA), a previously uncharacterized microbial metabolite involved in plant-microbe interactions. Microbially produced 6-OHNA is transported from roots to shoots, where it primes systemic immune responses in a salicylic acid-dependent manner. Disruption of the microbial nic BGC abolishes immune priming, whereas increased VB3 exudation from plant roots enhances disease resistance. Together, these findings reveal a metabolically mediated dialog between plant hosts and their microbiota that links host nutrient secretion to microbial functional specialization and the activation of systemic plant immunity.

The gut microbiota forms a complex ecosystem through metabolic interdependence (cross-feeding). However, conventional fecal metabolomics typically quantifies only total metabolite pools, making it difficult to distinguish extracellular-enriched metabolite pools from predominantly cell-associated ones, and thus limiting reconstruction of in situ metabolic networks. Here, we quantifi

Nicotinamide adenine dinucleotides (NAD+, NADH, NADP+ and NADPH) and glutathione (GSH and GSSG) metabolites are vital regulators of redox state, enzyme functions, and metabolic flux in hundreds of cellular metabolic reactions. NAD+/NADH ratio increases during fasting and has been associated with health outcomes in model systems. A low ratio occurs in specific diseases, treated with high-dose B3-vitamin forms, so-called NAD+-boosters. Still, neither healthy human values nor NAD+ booster-treated or disease-related levels of NAD(P)(H) or glutathione have been established in humans. Here, we report a standardized workflow of enzymatic cycling assays to quantitatively measure NAD+, NADH, NADP+, NADPH, GSH, and GSSG from a single whole-blood sample. In the blood of a healthy population aged 18-70 years, these metabolites follow a normal distribution and remain unchanged during aging. High-dose nicotinic acid, a B3 vitamin, resulted in 4-6-fold increase of blood NAD+ in healthy individuals, suggesting the need for personalized dosing and follow-up in treatment and drug trials. Our data also indicate disease-dependent "redox fingerprints" of NAD and glutathione forms in different degenerative diseases, including cancers. The evidence highlights the potential of redox profiling as an indicator of probable pathology and as a measure of treatment response.

Comment in JAMA Ophthalmol. 2026 Aug 1;144(8):731-732. doi: 10.1001/jamaophthalmol.2026.2622. IMPORTANCE: Ocular hypertension (OHT) is a primary risk factor for primary open-angle glaucoma (POAG), and systemic nicotinamide has emerged as a potential metabolic prophylactic intervention to prevent conversion; however, real-world evidence is lacking. OBJECTIVE: To determine whether systemic nicotinamide supplementation, with potential neuroprotective properties, is associated with reduced risk of POAG diagn