Omega-7 (Palmitoleic Acid)

OBJECTIVE: To summarize the associations between potential causal factors and colorectal cancer (CRC) risk based on existing Mendelian randomization studies. METHODS: This systematic review and meta-analysis involved a literature search in Embase and Medline. All published articles using Mendelian randomization to explore potential causal factors of CRC were included. Studies that reported Mendelian randomization estimates of standard deviation changes in exposures were included in the meta-analysis. Subgroup analyses based on sex and anatomical sites were performed. RESULTS: One hundred and ninety studies presented in 51 articles were included in systematic review, and 114 studies conducted in 32 articles were included in the meta-analysis. Adult body mass index, waist circumference, waist hip ratio, body height, body fat percentage, arm fat ratio, childhood obesity, lifetime cigarette consumption, short sleep, coffee consumption, and blood levels of vitamin B12 , arachidonic acid, stearic acid, and insulin-like growth factor binding protein 3 were positively associated with CRC risk. Conversely, acceleration-vector-magnitude physical activity, milk consumption, and blood levels of adiponectin, linoleic acid, α-linolenic acid, oleic acid, palmitoleic acid, interleukin-6 receptor subunit-α, and tumor necrosis factor were inversely associated with CRC risk. CONCLUSIONS: Most obesity-related anthropometric characteristics, several unhealthy lifestyles, and blood levels of some micronutrients, fatty acids, and diabetes-related biomarkers were positively associated with CRC risk. In contrast, some lifestyles and blood levels of some fatty acids and inflammatory biomarkers were inversely associated with CRC risk. Future studies with more valid genetic variants are needed for factors with discrepancies between Mendelian randomization and epidemiological studies. © 2022 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

BACKGROUND: We aimed to investigate the association of serum pentadecanoic acid (15:0), a biomarker of dairy fat intake, with incident cardiovascular disease (CVD) and all-cause mortality in a Swedish cohort study. We also systematically reviewed studies of the association of dairy fat biomarkers (circulating or adipose tissue levels of 15:0, heptadecanoic acid [17:0], and trans-palmitoleic acid [t16:1n-7]) with CVD outcomes or all-cause mortality. METHODS AND FINDINGS: We measured 15:0 in serum cholesterol esters at baseline in 4,150 Swedish adults (51% female, median age 60.5 years). During a median follow-up of 16.6 years, 578 incident CVD events and 676 deaths were identified using Swedish registers. In multivariable-adjusted models, higher 15:0 was associated with lower incident CVD risk in a linear dose-response manner (hazard ratio 0.75 per interquintile range; 95% confidence interval 0.61, 0.93, P = 0.009) and nonlinearly with all-cause mortality (P for nonlinearity = 0.03), with a nadir of mortality risk around median 15:0. In meta-analyses including our Swedish cohort and 17 cohort, case-cohort, or nested case-control studies, higher 15:0 and 17:0 but not t16:1n-7 were inversely associated with total CVD, with the relative risk of highest versus lowest tertile being 0.88 (0.78, 0.99), 0.86 (0.79, 0.93), and 1.01 (0.91, 1.12), respectively. Dairy fat biomarkers were not associated with all-cause mortality in meta-analyses, although there were ≤3 studies for each biomarker. Study limitations include the inability of the biomarkers to distinguish different types of dairy foods and that most studies in the meta-analyses (including our novel cohort study) only assessed biomarkers at baseline, which may increase the risk of misclassification of exposure levels. CONCLUSIONS: In a meta-analysis of 18 observational studies including our new cohort study, higher levels of 15:0 and 17:0 were associated with lower CVD risk. Our findings support the need for clinical and experimental studies to elucidate the causality of these relationships and relevant biological mechanisms.

This meta-analysis was carried to evaluate the effect of the use of crude glycerin in diets for beef cattle on the ruminal fermentation, animal performance, physical and chemical characteristics, and fatty acid profile of meat through meta-analysis. Data from forty-eight peer-reviewed publications with 170 treatments means was included in the data set. The effect glycerin in diet were evaluated by examining the weighted mean differences (WMD) between glycerin treatment (diets with crude glycerin) and control diet (without crude glycerin). Heterogeneity was explored by meta-regression and subgroup analysis using genetic type, treatment period, crude glycerin in the diet (g/kg DM), feed systems (pasture or total mixed ration), and concentrate in the diet (g/kg DM). The inclusion of crude glycerin had no effect on the average daily gain, but increased feed efficiency by 3.15% while reducing subcutaneous fat thickness by 3.13%. Inclusion of crude glycerin reduced meat cholesterol by 9.13%, and total saturated fatty acids by 1.05%, and increased total unsaturated (2.02%), monounsaturated (3.17%) fatty acids. However, it did not affect the concentrations of conjugated linoleic acid and omega-3. Crude glycerin inclusions up to 200 g/kg DM did not promote a negative effect on animal performance, carcass and physical-chemical characteristics of meat, and supported an increase in total monounsaturated (1.73%), oleic acid (12.29 mg) and palmitoleic acid (1.24 mg), while reducing myristic acid (3.08 mg), stearic acid (12.00 mg) in beef cattle meat.

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with increased risks of disease for mother and child during pregnancy and after that. Early diagnosis of GDM would promote both maternal and fetal health. Metabolomics can simplify and develop our understanding of the etiology, manifestation, or pathophysiology of the disease. This systematic review investigates the association of circulating omega 3, 6, and 9 fatty acids with GDM. METHODS: We conducted a systematic search of PubMed, Scopus, Web of Science, and EMBASE databases up to May 8, 2020, using the key term combinations of all types of omega fatty acids with gestational diabetes mellitus. Additional articles were identified through searching the reference lists of included studies. RESULTS: This systematic review included 15 articles. Five were cohort studies, four included nested case-control studies and four were case-control studies. The results of this study demonstrate an increasing trend in the amount of oleic acid and palmitoleic acid in the second trimester and an increase in decosahexanoic acid in the third trimester of GDM mothers. The changes in other fatty acids of interest are either not significant or if significant, their results are inconsistent with the other existing articles. CONCLUSIONS: Omega fatty acids, as potential biomarkers, are considered to be associated with GDM risk and thus provide useful information regarding the prevention and early diagnosis of GDM. Moreover, existing metabolomic studies on GDM are shown to provide conflicting results about metabolite profile characteristics. This systematic review was registered at PROSPERO ( www.crd.york.ac.uk/PROSPERO ) as CRD42020196122.

Background/Aim: Several observational studies evaluated the links between serum monounsaturated fatty acids (MUFAs) and cardiovascular events with controversial results. In the present study, Mendelian randomization (MR) analysis was applied to obtain unconfounded estimates of the causal associations of genetically determined serum MUFAs with coronary heart disease (CHD), myocardial infarction (MI), cardioembolic stroke (CS), and ischemic stroke (IS). Methods: Four MUFAs were studied (i.e., 10-heptadecenoate, myristoleic, oleic, and palmitoleic acid). Data from the largest genome-wide association studies on MUFAs, CHD, MI, and stroke were analyzed. Inverse variance weighted method (IVW), weighted median (WM)-based method, MR-Egger, as well as MR-pleiotropy residual sum and outlier were applied. To rule out the impact of single-nucleotide polymorphism (SNP), the leave-one-out method was also performed. Results: Genetically higher-serum 10-heptadecenoate levels did not affect the risk of CHD (IVW = Beta: -0.304, p = 0.185), MI (IVW = Beta: -0.505, p = 0.066), CS (IVW = Beta: -0.056, p = 0.945), and IS (IVW = Beta: -0.121, p = 0.767). Similarly, no significant associations were observed for myristoleic acid (CHD: IVW = Beta: 0.008; MI: IVW = Beta: 0.041; CS: IVW = Beta: 0.881; IS: IVW = Beta: 0.162), oleic acid (CHD: IVW = Beta: -0.2417; MI: IVW = Beta: -0.119; CS: IVW = Beta: 1.059; IS: IVW = Beta: 0.008491), and palmitoleic acid (CHD: IVW = Beta: -0.06957; MI: IVW = Beta: -0.01255; CS: IVW = Beta: 1.042; IS: IVW = Beta: -0.1862). A low likelihood of heterogeneity and pleiotropy was reported, and the observed associations were not driven by single SNPs. Conclusions: In the present MR analysis, serum MUFA levels were not associated with the risk of CHD, MI, CS, and IS. Further research, evaluating more MUFAs, is required to elucidate the links between MUFAs and CVD to contribute to health policy decisions in reducing CVD risk.

Major depressive disorder (MDD) is a serious mental illness, characterized by high morbidity, which has increased in recent decades. However, the molecular mechanisms underlying MDD remain unclear. Previous studies have identified altered metabolic profiles in peripheral tissues associated with MDD. Using curated metabolic characterization data from a large sample of MDD patients, we meta-analyzed the results of metabolites in peripheral blood. Pathway and network analyses were then performed to elucidate the biological themes within these altered metabolites. We identified 23 differentially expressed metabolites between MDD patients and controls from 46 studies. MDD patients were characterized by higher levels of asymmetric dimethylarginine, tyramine, 2-hydroxybutyric acid, phosphatidylcholine (32:1), and taurochenodesoxycholic acid and lower levels of L-acetylcarnitine, creatinine, L-asparagine, L-glutamine, linoleic acid, pyruvic acid, palmitoleic acid, L-serine, oleic acid, myo-inositol, dodecanoic acid, L-methionine, hypoxanthine, palmitic acid, L-tryptophan, kynurenic acid, taurine, and 25-hydroxyvitamin D compared with controls. L-tryptophan and kynurenic acid were consistently downregulated in MDD patients, regardless of antidepressant exposure. Depression rating scores were negatively associated with decreased levels of L-tryptophan. Pathway and network analyses revealed altered amino acid metabolism and lipid metabolism, especially for the tryptophan-kynurenine pathway and fatty acid metabolism, in the peripheral system of MDD patients. Taken together, our integrated results revealed that metabolic changes in the peripheral blood were associated with MDD, particularly decreased L-tryptophan and kynurenic acid levels, and alterations in the tryptophan-kynurenine and fatty acid metabolism pathways. Our findings may facilitate biomarker development and the elucidation of the molecular mechanisms that underly MDD. © 2020. The Author(s).

BACKGROUND: Chronic illnesses like obesity, type 2 diabetes (T2D) and cardiovascular diseases, are worldwide major causes of morbidity and mortality. These pathological conditions involve interactions between environmental, genetic, and epigenetic factors. Recent advances in nutriepigenomics are contributing to clarify the role of some nutritional factors, including dietary fatty acids in gene expression regulation. This systematic review assesses currently available information concerning the role of the different fatty acids on epigenetic mechanisms that affect the development of chronic diseases or induce protective effects on metabolic alterations. METHODS: A targeted search was conducted in the PubMed/Medline databases using the keywords "fatty acids and epigenetic". The data were analyzed according to the PRISMA-P guidelines. RESULTS: Consumption fatty acids like n-3 PUFA: EPA and DHA, and MUFA: oleic and palmitoleic acid was associated with an improvement of metabolic alterations. On the other hand, fatty acids that have been associated with the presence or development of obesity, T2D, pro-inflammatory profile, atherosclerosis and IR were n-6 PUFA, saturated fatty acids (stearic and palmitic), and trans fatty acids (elaidic), have been also linked with epigenetic changes. CONCLUSIONS: Fatty acids can regulate gene expression by modifying epigenetic mechanisms and consequently result in positive or negative impacts on metabolic outcomes.

OBJECTIVES: Eating disorders result in poor nutrition, poor physical conditions and even suicidality and mortality. Although polyunsaturated fatty acids (PUFAs) have attracted attention in the emerging field of nutritional psychiatry, their role in eating disorders remains unknown. This meta-analysis investigates the differences of PUFA levels between patients with eating disorders and healthy controls, and the potentially beneficial effects of PUFAs in such patients. METHODS: We conducted a systematic literature search and meta-analysis under the random effects model. RESULT: Eleven studies were included in the current meta-analysis. Compared with controls, 379 patients with eating disorders had significantly higher plasma levels of alpha-linolenic acid, eicosapentaenoic acid, stearidonic acid, osbond acid, palmitoleic acid, oleic acid, and total omega-3 fatty acids; and lower levels of total omega-6 fatty acids and omega-6/omega-3 ratio. Eating disorders were associated with significantly higher red blood cell membrane levels of palmitoleic acid and oleic acid and lower levels of adrenic acid, arachidonic acid, and total omega-6 fatty acids. In addition, PUFA supplements were associated with a benefit to body weight outcomes but not disease severity and mood symptoms in interventional trials. DISCUSSION: This meta-analysis indicates abnormal levels of PUFAs in peripheral blood tissues in patients with eating disorders. The relationship between PUFAs and eating disorders should be interpreted cautiously considering the specific lipid metabolism under starvation state. To investigate the role of PUFAs on psychopathological and therapeutic effects in eating disorders, further larger clinical studies are warranted.

BACKGROUND: We aimed to investigate prospective associations of circulating or adipose tissue odd-chain fatty acids 15:0 and 17:0 and trans-palmitoleic acid, t16:1n-7, as potential biomarkers of dairy fat intake, with incident type 2 diabetes (T2D). METHODS AND FINDINGS: Sixteen prospective cohorts from 12 countries (7 from the United States, 7 from Europe, 1 from Australia, 1 from Taiwan) performed new harmonised individual-level analysis for the prospective associations according to a standardised plan. In total, 63,682 participants with a broad range of baseline ages and BMIs and 15,180 incident cases of T2D over the average of 9 years of follow-up were evaluated. Study-specific results were pooled using inverse-variance-weighted meta-analysis. Prespecified interactions by age, sex, BMI, and race/ethnicity were explored in each cohort and were meta-analysed. Potential heterogeneity by cohort-specific characteristics (regions, lipid compartments used for fatty acid assays) was assessed with metaregression. After adjustment for potential confounders, including measures of adiposity (BMI, waist circumference) and lipogenesis (levels of palmitate, triglycerides), higher levels of 15:0, 17:0, and t16:1n-7 were associated with lower incidence of T2D. In the most adjusted model, the hazard ratio (95% CI) for incident T2D per cohort-specific 10th to 90th percentile range of 15:0 was 0.80 (0.73-0.87); of 17:0, 0.65 (0.59-0.72); of t16:1n7, 0.82 (0.70-0.96); and of their sum, 0.71 (0.63-0.79). In exploratory analyses, similar associations for 15:0, 17:0, and the sum of all three fatty acids were present in both genders but stronger in women than in men (pinteraction < 0.001). Whereas studying associations with biomarkers has several advantages, as limitations, the biomarkers do not distinguish between different food sources of dairy fat (e.g., cheese, yogurt, milk), and residual confounding by unmeasured or imprecisely measured confounders may exist. CONCLUSIONS: In a large meta-analysis that pooled the findings from 16 prospective cohort studies, higher levels of 15:0, 17:0, and t16:1n-7 were associated with a lower risk of T2D.

BACKGROUND: Regular fish and omega-3 consumption may have several health benefits and are recommended by major dietary guidelines. Yet, their intakes remain remarkably variable both within and across populations, which could partly owe to genetic influences. OBJECTIVE: To identify common genetic variants that influence fish and dietary eicosapentaenoic acid plus docosahexaenoic acid (EPA+DHA) consumption. DESIGN: We conducted genome-wide association (GWA) meta-analysis of fish (n = 86,467) and EPA+DHA (n = 62,265) consumption in 17 cohorts of European descent from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) Consortium Nutrition Working Group. Results from cohort-specific GWA analyses (additive model) for fish and EPA+DHA consumption were adjusted for age, sex, energy intake, and population stratification, and meta-analyzed separately using fixed-effect meta-analysis with inverse variance weights (METAL software). Additionally, heritability was estimated in 2 cohorts. RESULTS: Heritability estimates for fish and EPA+DHA consumption ranged from 0.13-0.24 and 0.12-0.22, respectively. A significant GWA for fish intake was observed for rs9502823 on chromosome 6: each copy of the minor allele (FreqA = 0.015) was associated with 0.029 servings/day (~1 serving/month) lower fish consumption (P = 1.96x10-8). No significant association was observed for EPA+DHA, although rs7206790 in the obesity-associated FTO gene was among top hits (P = 8.18x10-7). Post-hoc calculations demonstrated 95% statistical power to detect a genetic variant associated with effect size of 0.05% for fish and 0.08% for EPA+DHA. CONCLUSIONS: These novel findings suggest that non-genetic personal and environmental factors are principal determinants of the remarkable variation in fish consumption, representing modifiable targets for increasing intakes among all individuals. Genes underlying the signal at rs72838923 and mechanisms for the association warrant further investigation.

BACKGROUND: Palmitoleic acid (POA) is an n-7 monounsaturated fatty acid. Preclinical studies suggest cis-POA lowers inflammation and improves metabolism. However, the impact of POA supplementation on inflammatory/metabolic biomarkers in humans is not well understood. OBJECTIVES: The primary aim was to investigate if cis-POA lowers circulating high-sensitivity C-reactive protein (hs-CRP) relative to placebo. Secondary endpoints were interleukin-6, tumor necrosis factor-α, fasting glucose, insulin, glycosylated hemoglobin, low-density lipoprotein cholesterol, red blood cell (RBC), and plasma fatty acid concentration. Exploratory endpoints were total cholesterol, high-density lipoprotein cholesterol, triglycerides, leptin, ghrelin, peptide YY, and adiponectin. METHODS: The randomized double-blinded parallel arm trial enrolled 123 participants with hs-CRP concentrations of 2 mg/L or higher. Participants consumed 500 mg/d or 1000 mg/d of marine-source POA or placebo for 12 wk. Fasting blood draws were used to quantify plasma inflammatory/metabolic biomarkers at baseline and 12-wk by multiplex immunoassays. Plasma and RBC POA concentrations were quantified with gas chromatography. Dietary intake was assessed with the Nutrition Data System for Research. Analysis of covariance analysis was used to investigate if there is an effect of either baseline or dosage on inflammatory/metabolic biomarkers. RESULTS: At baseline, all 3 groups had similar hs-CRP concentrations [geometric mean (standard deviation) = 0.57 (0.17), 0.54 (0.20), and 0.53 (0.23)] at 1000 mg/d, 500 mg/d, and placebo, respectively. There were no changes in hs-CRP concentration within and between the 3 groups in response to the supplementation. Analysis of covariance analysis showed there was no significant influence of baseline hs-CRP or POA dosage on changes in hs-CRP. There were also no changes in secondary or exploratory endpoints in response to placebo or POA. Significant changes were measured in select plasma and RBC fatty acids that were significantly related to POA dosage (P < 0.001) but not baseline. CONCLUSIONS: Compared to placebo, supplementation for 12 wk with 500 mg/d or 1000 mg/d POA did not s

Comment in J Clin Endocrinol Metab. 2026 May 19;111(6):e1708-e1709. doi: 10.1210/clinem/dgaf469. CONTEXT: Carbohydrate restriction benefits metabolic health in patients with type 2 diabetes (T2D), possibly through changes in hepatic metabolism. OBJECTIVE: To test the hypothesis that the ketogenic diet (KD) would decrease de novo lipogenesis (DNL) and liver fat, which would be associated with restored beta-cell function. METHODS: Participants were 57 adults with mild T2D. A hyperglycemic clamp was used to assess acute C-peptide response (ACP), and magnetic resonance imaging to assess hepatic fat fraction, at baseline and after 12 weeks of either a eucaloric KD (∼9% energy from carbohydrate, 65% energy from fat) or a eucaloric low-fat diet (LFD) (∼55% energy from carbohydrate, 20% energy from fat). RESULTS: The KD led to decreases in pyruvate (-23%, P < .001) and palmitoleic acid, a marker of DNL (-32%, P < .01). Participants on the KD had higher fasting glucagon (25%, P < .05) and lower liver fat (28%, P < .05) at week 12 than those on the LFD. In all combined, the change in liver fat was positively associated with the change in pyruvate (r = 0.45, P = .05), and inversely associated with changes in glucagon (r = -0.34, P < .05), the glucagon to C-peptide ratio (r = -0.44, P < .01), and ACP (r = -0.34, P < .05). The change in ACP was inversely associated with the change in pyruvate in the KD group (r = -0.5, P < .05), but not in the LFD group. CONCLUSION: A shift in hepatic metabolism to favor fat oxidation over DNL may underlie the beneficial effects of carbohydrate restriction on hepatic steatosis and glucose-induced insulin secretion. © The Author(s) 2025. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact [email protected] for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact [email protected]. See the journal About page for additional terms.

7-MEGATM is a food product made from purified Alaska pollack fish oil containing palmitoleic acid (16:1), commonly referred to as omega-7. We sought to quantitatively evaluate whether this substance inhibits skin aging. A total of 101 middle-aged females were randomly allocated to the intervention (N = 50) or placebo group (N = 51). Each participant was advised to take either 500 mg of 7-MEGATM or a placebo twice daily for 12 weeks. The primary outcomes were the degree of improvement in wrinkles and the degree of moisture filling after consumption for 12 weeks compared to baseline. The secondary outcomes were improvement in skin wrinkles; moisture changes at 4 and 8 weeks from baseline; changes in transdermal water loss, skin elasticity, the melanin index, the erythema index, and the Global Photo Damage Score. We found a significant improvement in skin wrinkles and elasticity at 12 weeks in the 7-MEGATM-consuming group compared to that in the placebo group; skin moisture, elasticity, and the melanin index were also improved. No supplement-related adverse reactions were observed and 7-MEGATM was identified as safe. 7-MEGATM was effective for human skin function in terms of wrinkles, moisture, elasticity, and melanin production and may be useful as a skin nutritional supplement.

We sought to examine the effects of daily consumption of macadamia nuts on body weight and composition, plasma lipids and glycaemic parameters in a free-living environment in overweight and obese adults at elevated cardiometabolic risk. Utilising a randomised cross-over design, thirty-five adults with abdominal obesity consumed their usual diet plus macadamia nuts (~15 % of daily calories) for 8 weeks (intervention) and their usual diet without nuts for 8 weeks (control), with a 2-week washout. Body composition was determined by bioelectrical impedance; dietary intake was assessed with 24-h dietary recalls. Consumption of macadamia nuts led to increased total fat and MUFA intake while SFA intake was unaltered. With mixed model regression analysis, no significant changes in mean weight, BMI, waist circumference, percent body fat or glycaemic parameters, and non-significant reductions in plasma total cholesterol of 2⋅1 % (-4⋅3 mg/dl; 95 % CI -14⋅8, 6⋅1) and low-density lipoprotein (LDL-C) of 4 % (-4⋅7 mg/dl; 95 % CI -14⋅3, 4⋅8) were observed. Cholesterol-lowering effects were modified by adiposity: greater lipid lowering occurred in those with overweight v. obesity, and in those with less than the median percent body fat. Daily consumption of macadamia nuts does not lead to gains in weight or body fat under free-living conditions in overweight or obese adults; non-significant cholesterol lowering occurred without altering saturated fat intake of similar magnitude to cholesterol lowering seen with other nuts. Clinical Trial Registry Number and Website: NCT03801837 https://clinicaltrials.gov/ct2/show/NCT03801837?term = macadamia + nut&draw = 2&rank = 1. © The Author(s) 2023.

OBJECTIVE: To study the effect of Guilu Erxian ointment on the outcome of IVF-ET in older patients with poor ovarian response infertility of kidney-qi deficiency type, and to verify and analyze the mechanism of action of traditional Chinese medicine on improving older patients with poor ovarian response infertility of kidney-qi deficiency type from the perspective of metabolomics using targeted metabolomics technology, identify the related metabolic pathways, and provide metabolic biomarker basis and clinical treatment ideas for improving older patients with poor ovarian response infertility. METHODS: This study was a double-blind, randomized, placebo-controlled trial, and a total of 119 infertile patients who underwent IVF-ET at Shandong Center for Reproduction and Genetics of Integrated Traditional Chinese and Western Medicine were selected. Eighty older patients with infertility undergoing IVF were randomly divided into older treatment group and older placebo group, and another 39 young healthy women who underwent IVF-ET or ICSI due to male factors were selected as the normal control group. Flexible GnRH antagonist protocol was used for ovulation induction in all three groups, and Guilu Erxian ointment and placebo groups started taking Guilu Erxian ointment and placebo from the third day of menstruation until IVF surgery. And ultra-high performance liquid chromatography-triple quadrupole mass spectrometer (UHPLC-QTRAP MS) was used to detect metabolites in the three groups of samples. RESULTS: Compared with the placebo group, the number of oocytes retrieved, 2PN fertilization, high-quality embryos, total number of available embryos and estrogen on HCG day were increased in the treatment group, and the differences were statistically significant (P > 0.05), but the clinical pregnancy rate of fresh embryos and frozen embryos were not statistically significant (P > 0.05). The results of targeted metabolomics analysis showed that follicular fluid in the treatment group clustered with the normal young group and deviated from the placebo group. A total of 55 significant differential metabolites were found in the follicular fluid of older patients with poor ovarian re

BACKGROUND: Fatty acids increase ATP-binding cassette ABC transporter A12 (ABCA12) levels via an increase in peroxisome proliferator-activated receptor β/δ (PPAR β/δ). Promoting lipid transport to lamellar granules has been suggested to improve epidermal barrier function in patients with dry skin. OBJECTIVE: We investigated whether mevalonolactone (MVL) produced by Saccharomycopsis fibuligera improves dry skin by promoting ABCA12 expression and the amount of free fatty acids in epidermal keratinocytes. METHODS: We examined whether MVL increases ABCA12 mRNA and protein levels and the amount of Nile red-positive lipids in cultured epidermal keratinocytes and in a three-dimensional epidermal model by cell staining. Promotion of fatty acid production by MVL was analyzed by liquid chromatography-mass spectrometry. We also evaluated whether MVL addition increases PPAR β/δ mRNA expression in cultured keratinocytes. Based on the results, a randomized controlled trial was conducted in which milky lotions containing MVL and placebo were applied to dry facial skin of healthy female volunteers in winter. RESULTS: MVL increased ABCA12 mRNA and protein levels and lamellar granule number and size. Fatty acid analysis revealed that MVL elevated myristic acid, palmitic acid, and palmitoleic acid levels as well as PPAR β/δ mRNA expression. In human tests, milky lotions containing MVL were shown to significantly improve transepidermal water loss (TEWL) in the stratum corneum compared to placebo. CONCLUSION: The results suggest that MVL increases fatty acid uptake and ABCA12, promotes fatty acid transport to lamellar granules, and improves epidermal barrier function in dry skin through increased expression of PPAR β/δ. © 2022 The Authors. Skin Research and Technology published by John Wiley & Sons Ltd.

The burden of disease associated with acne vulgaris has continued to increase over time in the world population. This continued growth suggests that there is an unmet dermatologic need for this condition worldwide. Potential sequelae of acne, such as scarring, depigmentation, and marked emotional and psychological problems (e.g., low self-esteem), can lead to significant morbidity. The purpose of this study was to investigate whether dietary supplementation with magnesium, phosphate, omega 6 (linoleic acid calcium salt - C18:2 fatty acid Ca salt), and omega 7 (palmitoleic acid calcium salt - C16:1 fatty acid Ca salt) would help patients with acne vulgaris, and to compare with isotretinoin (13-cis retinoic acid). Magnesium has anti-inflammatory properties. Linoleic and palmitoleic acids have bactericidal activity against Staphylococcus aureus and Cutibacterium acnes (formerly known as Propionibacterium acnes). A single-blind randomized study was conducted in which 257 patients were treated with the above dietary supplementation (group A) and 275 patients with isotretinoin (group B) for 6 months. All patients in group A (100%) reported complete regression of symptoms after 6 months of treatment. On the other hand, 187 subjects (68%) in group B reported complete resolution of symptoms during the same period. The difference between the groups (p < 0.05) was statistically significant. The study was approved by the CEP/CONEP. This natural formulation promotes regression and/or cure of acne vulgaris symptoms and has better results than drugs (such as isotretinoin), without significant side effects.

BACKGROUND: Non-alcoholic liver steatosis (NAS) results from an imbalance between hepatic lipid storage, disposal, and partitioning. A multifactorial diet high in fiber, monounsaturated fatty acids (MUFAs), n-6 and n-3 polyunsaturated fatty acids (PUFAs), polyphenols, and vitamins D, E, and C reduces NAS in people with type 2 diabetes (T2D) by 40% compared to a MUFA-rich diet. We evaluated whether dietary effects on NAS are mediated by changes in hepatic de novo lipogenesis (DNL), stearoyl-CoA desaturase (SCD1) activity, and/or β-oxidation. METHODS: According to a randomized parallel group study design, 37 individuals with T2D completed an 8-week isocaloric intervention with a MUFA diet (n = 20) or multifactorial diet (n = 17). Before and after the intervention, liver fat content was evaluated by proton magnetic resonance spectroscopy, serum triglyceride fatty acid concentrations measured by gas chromatography, plasma β-hydroxybutyrate by enzymatic method, and DNL and SCD-1 activity assessed by calculating the palmitic acid/linoleic acid (C16:0/C18:2 n6) and palmitoleic acid/palmitic acid (C16:1/C16:0) ratios, respectively. RESULTS: Compared to baseline, mean ± SD DNL significantly decreased after the multifactorial diet (2.2 ± 0.8 vs. 1.5 ± 0.5, p = 0.0001) but did not change after the MUFA diet (1.9 ± 1.1 vs. 1.9 ± 0.9, p = 0.949), with a significant difference between the two interventions (p = 0.004). The mean SCD-1 activity also decreased after the multifactorial diet (0.13 ± 0.05 vs. 0.10 ± 0.03; p = 0.001), but with no significant difference between interventions (p = 0.205). Fasting plasma β-hydroxybutyrate concentrations did not change significantly after the MUFA or multifactorial diet. Changes in the DNL index significantly and positively correlated with changes in liver fat (r = 0.426; p = 0.009). CONCLUSIONS: A diet rich in multiple beneficial dietary components (fiber, polyphenols, MUFAs, PUFAs, and other antioxidants) compared to a diet rich only in MUFAs further reduces liver fat accumulation through the inhibition of DNL. Registered under ClinicalTrials.gov no. NCT03380416.

Yogurt consumption shows a wide range of effects on the gut microbial composition, and correlation of components in yogurt with the changes of gut microbia remains largely uncharacterized. We aimed to determine the effect of brown yogurt (SSN) on the composition of the gut microbiota and to explore the effects of the major components. We performed a randomized study of 70 healthy adults to compare the effects of SSN and standard probiotic-containing yogurt (YJD) during a 28-day intervention and a 10-day follow-up period. The results showed that the SSN group showed significant increases in the butyrate-producer Akkermansia muciniphila, Ruminococcus, and Veillonella (p < 0.05), whereas the YJD group showed increases in the butyrate-producer Megasphaera, Anaerostipes, and Eubacterium. There were reductions in the potential pathogens Haemophilus parainfluenzae and Gemmiger formicilis in both groups (p < 0.05). The SSN group had more Faecalibacterium prausnitzii, Prevotella copri, Bifidobacterium and B. longum than the YJD group (p < 0.001), but fewer Bacteroides, unspecified Clostridiales and Coprococcus eutactus (p < 0.01). These differences might be at least in part explained by the higher concentrations of monosaccharide, palmitoleic acid, and glutamine synthetase adenyltransferase in the SSN product (p < 0.05), which were positively associated with F. prausnitzii (p ≤ 0.001) and B. longum (p < 0.05), and negatively associated with C. eutactus (p < 0.01). The single strain of starter culture and lower content of polyunsaturated fatty acids (PUFA) in the SSN product were also related to the different changes of gut microbia, and the taxa F. prausnitzii, Bifidobacterium and B. longum were negatively associated with starter culture and PUFA (p < 0.01). These findings suggested that SSN is rich in prebiotic components and might be beneficial for healthy adults. Furthermore, bacterial taxa with potential health benefits could be encouraged through improving the formulation and technology used to produce the dairy products.

BACKGROUND: Plasma phospholipid pentadecanoic acid (C15:0), heptadecanoic acid (C17:0), and trans-palmitoleic acid (trans-C16:1n-7) are correlates of dairy fat intake. However, their relative concentrations may be influenced by other endogenous factors, such as liver fat content, and their validity as biomarkers of dairy fat intake has yet to be established. OBJECTIVES: We investigated whether liver fat content modifies relations between concentrations of C15:0, C17:0, and trans-C16:1n-7 (alone and in combination with iso-C17:0) and known dairy fat intake in the context of a randomized controlled intervention study. We further examined the proportion of dairy fat intake explained by these fatty acids on their own and when considering liver fat content. METHODS: We used data from a 12-wk intervention trial in which participants (n = 62) consumed diets limited in dairy (0.3 g/d of dairy fat), rich in low-fat dairy (8.7 g/d of dairy fat), or rich in full-fat dairy (28.5 g/d of dairy fat). We used linear regression models to examine relations between relative fatty acid concentrations and grams per day of dairy fat intake, liver fat percentage, and their interaction. RESULTS: Only trans-C16:1n-7 in isolation (β: 0.0004 ± 0.0002, P = 0.03) and combined with iso-C17:0 (β: 0.002 ± 0.0005, P < 0.0001) were consistently positively associated with dairy fat intake regardless of liver fat content. Trans-C16:1n-7 combined with iso-C17:0 also explained the greatest proportion of variation (35.4%) in dairy fat intake. C15:0 and C17:0 were not associated with dairy fat intake after adjusting for liver fat and were predicted to be higher in relation to increased dairy fat intake only among individuals with elevated liver fat. CONCLUSIONS: The potential for liver fat to affect relative plasma phospholipid concentrations of C15:0 and C17:0 raises questions about their validity as biomarkers of dairy fat intake. Of the fatty acid measures tested, trans-C16:1n-7 combined with iso-C17:0, especially with adjustment of liver fat, age, and sex, may provide the most robust estimate of dairy fat consumption. © The Author(s) 2022. Published by Oxford University Press on behalf of the Ame

Erratum in Nutr Res. 2026 Aug;152:171. doi: 10.1016/j.nutres.2026.06.004. Dairy foods are becoming one of the major dietary sources of trans fatty acids (TFA) as global initiatives to eliminate industrially produced TFA are implemented. This systematic review aimed to assess the cardiometabolic effects of TFA from dairy foods, using data from randomized controlled trials (RCTs) and prospective cohort studies (PCS). We hypothesized that TFA from dairy foods would have no effect on biomarkers for or risk of cardiovascular diseases. Searches for RCTs and PCS were conducted in PubMed and EMBASE using PRISMA guidelines. RCTs compared the impact on blood lipids of regular dairy foods with TFA-enhanced dairy fat/foods produced by altering the cow's diet. Pooled meta-analysis of RCTs using the random effects model was performed for total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), total cholesterol/HDL-C, low-density lipoprotein cholesterol/HDL-C, triacylglycerols, apolipoprotein A1, and apolipoprotein B as continuous variables. Selected PCS analyzed associations between blood concentrations of trans vaccenic acid or trans palmitoleic acid and risk of cardiovascular diseases or type 2 diabetes. Among 10 RCTs, there were no significant differences in mean difference for any lipid biomarkers except for a slight decrease in HDL-C (mean difference: -0.05 mmol/L; confidence interval: -0.10 to -0.00) for TFA-enriched vs. regular dairy foods. Among 12 PCS, circulating concentrations of trans vaccenic acid or trans palmitoleic acid were not associated with increased risk of cardiovascular diseases incidence, mortality, or type 2 diabetes. Consumption of TFA (1.3-13.2 g/d) from different types of dairy foods was not linked to adverse effects on cardiometabolic health.

Bladder cancer is a major public health concern worldwide. While smoking and occupational exposures are established risk factors, the role of dietary fatty acids (FAs) in bladder cancer risk remains unclear. Data were collected from 711 bladder cancer cases and 3,297 controls in the IROPICAN study (2017-2020) across ten Iranian provinces. Dietary intake was assessed using a validated food frequency questionnaire. Intakes of total fat, saturated FAs (SFAs), monounsaturated FAs (MUFAs), polyunsaturated FAs (PUFAs), and trans FAs (TFAs) were analyzed. Principal component analysis (PCA) identified fatty acid consumption patterns. Multivariable logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for confounders. PCA suggested that balancing FA intake, specifically increasing omega-3 FAs, moderating omega-6, and reducing saturated fats, was associated with a favorable profile for bladder cancer risk. OR for stearic acid intake was 0.28 (95% CI: 0.12-0.67). Conversely, OR for high intake of palmitoleic acid, alpha-linolenic acid (ALA), and docosapentaenoic acid (DPA) was elevated. Sex-specific effects were found stearic acid was protective in men, while PUFAs were protective in women. No associations were observed for total fat or cholesterol. These results highlight the importance of FA subtypes, rather than total fat intake, in dietary recommendations.

Pathogenic Staphylococcus aureus and commensal Staphylococcus epidermidis encounter acidic pH and C16 fatty acids on human skin and are known to produce orthologous serine proteases SspA and Esp with documented pro-inflammatory roles. Using protease production as a potential biomarker of pathogenic and commensal phenotypes, we have conducted a detailed analysis of how S. aureus and S. epidermidis respond to C16 fatty acids at acidic pH. During growth at pH 5.5, palmitoleic acid C16:1 was more toxic to S. aureus, but toxicity was mitigated by saturated palmitic acid C16:0. Acidic pH and C16 fatty acids stimulated SspA protease production in S. aureus but repressed Esp in S. epidermidis. Although S. aureus biofilm formation was stimulated by C16:0, this effect was diminished by 25 µM C16:1, which promotes protease production, whereas S. epidermidis maintained strong biofilm in the presence of both C16:0 and C16:1. Exogenous C16:0 was directly incorporated into phospholipid by S. epidermidis but was extended to C18:0 and C20:0 in S. aureus prior to incorporation. This may account for altered signaling through the GraSR two-component sensor, such that in S. aureus, deletion of graS/R caused impaired growth at pH 5.5 in the presence of C16:1, which was restored by complementation with graS/R from S. aureus, but not S. epidermidis. These findings provide a model framework for understanding how S. aureus and S. epidermidis exhibit differential phenotypes, including protease production and biofilm formation in response to combined C16 fatty acids and acidic pH, which promote distinct differences in the remodeling of membrane phospholipid.IMPORTANCEHuman skin is a chemically hostile environment, with acidic pH and antimicrobial fatty acids that challenge microbial survival. Understanding how closely related Staphylococcus epidermidis and Staphylococcus aureus navigate these conditions is critical for distinguishing commensal behavior from pathogenic potential. Our research reveals that S. aureus and S. epidermidis, although genetically similar, employ markedly distinct adaptive mechanisms in response to identical skin-derived cues. Specifically, each species remodels its

Anisakid nematodes are widespread marine parasites with zoonotic potential and possible impact on fish nutritional quality. In this study, we investigated the lipid composition of L3 Anisakis larvae, the host fish tissue adjacent to the presence of parasites (belly flaps) and the tail (used as a control due to the absence of Anisakis larvae) of parasitized European hake (Merluccius merluccius), combining fatty acid profiling and advanced lipidomics. Fatty acid analysis revealed distinct profiles between the Anisakis spp. parasites and hake tissues, with Anisakis larvae showing higher levels of stearic acid (18:0), vaccenic acid (18:1n-7), and linoleic acid (18:2n-6), while hake tissues, namely the tail, contained more palmitic acid (16:0), palmitoleic acid (16:1n-7), docosahexaenoic acid (22:6n-3), and omega-3-rich polyunsaturated fatty acids in general. Principal component analysis positioned the parasitized tissue of the hake belly flaps as an intermediate group, suggesting possible local metabolic interference. Lipidomics identified a total of 477 different lipid species and highlighted the existence of the following differences: saturated triacylglycerols and ether-linked phosphatidylcholines, phosphatidylethanolamines, and sphingomyelins species were more prevalent in Anisakis larvae, while some highly unsaturated phosphatidylcholines and monounsaturated triglycerydes were more abundant in hake tissues; specific sphingomyelins and ether lipids were exclusive of the fish tissue adjacent to the parasites (belly flaps) and may represent potential biomarkers of Anisakis spp. infection. Together, these results suggest that Anisakis larvae may influence/modulate local lipid metabolism, with parasite influence being more pronounced in fish tissue closer to the infection site with regard to distant unparatized tissue. Ultimately, this work supports the use of lipid profiling for better understanding host-parasite interactions in marine fish and unveils applications for parasite infection detection. © 2026 The Authors.

Marine macroalgae are increasingly recognized as sources of bioactive compounds with potential benefits for metabolic health. This study investigated the chemical composition and metabolic effects of a 70% ethanol extract of the edible red alga Gracilaria coronopifolia in a high-fat diet (HFD)-induced obesity model in rats. Chemical profiling using liquid chromatography-high-resolution mass spectrometry (LC-HRMS) identified several classes of metabolites, including sterols, phenolic acids, flavonoids, and fatty acid derivatives such as palmitoleic acid, chlorogenic acid, gallic acid, and quercetin. Male Wistar rats were fed an HFD for 11 weeks to induce obesity and subsequently treated with G. coronopifolia extract (40-160 mg/kg body weight) for 28 days, with semaglutide (70 µg/kg) used as a pharmacological comparator. Supplementation with the extract significantly reduced obesity-related parameters compared with untreated HFD controls. The highest extract dose (160 mg/kg) decreased final body weight from 294.8 ± 43.3 g in HFD rats to 215.2 ± 11.9 g, reduced visceral fat mass from 22.7 ± 2.37 g to 7.63 ± 1.19 g, and lowered the adiposity index from 6.39 ± 0.45% to 3.31 ± 0.22%. The extract also improved serum lipid profiles, reducing triglyceride levels from 185.46 ± 11.58 mg/dL in the HFD group to 101.54 ± 24.29 mg/dL, while increasing HDL concentrations to 75.64 ± 4.73 mg/dL. In addition, treatment increased adiponectin levels (to 779.55 ± 15.66) and decreased leptin (4.94 ± 0.75) and amylin (532.44 ± 30.00) relative to obese controls. Histological analysis demonstrated a reduction in adipocyte hypertrophy. Gene expression analysis revealed downregulation of hypothalamic Npy and adipose Fas and Pparγ, together with upregulation of Pomc, Mc4r, and Cpt1. These findings suggest that G. coronopifolia extract improves metabolic disturbances associated with diet-induced obesity through coordinated regulation of appetite signaling and lipid metabolism, supporting its potential development as a marine-derived functional food ingredient.

INTRODUCTION: Atrial fibrillation (AF) risk factors are not fully understood. Reportedly, a relationship exists between fatty acid intake and AF occurrence. The relationship between fatty acid levels and AF requires further investigation, which could help elucidate AF risk factors and provide insights into its primary prevention. We investigated the relationship between serum fatty acids and AF using Mendelian randomization (MR) and gas chromatography-mass spectrometry (GC-MS). METHODS: MR was used to investigate the potential effects of fatty acids on AF. Patients hospitalized in the Department of Cardiology between May and June 2024 were enrolled and divided into AF and non-AF groups. Fatty acids were extracted from the serum using the methanol, n-hexane, methyl tert-butyl ether method and methylated using acetyl chloride. GC-MS analysis was used to separate and quantify these methylated mixtures. RESULTS: Preliminary MR analysis showed that palmitoleic acid and (2 or 3)-decenoic acid are risk factors for AF, while nonadecanoic, oleic, and α/γ-linolenic acids are protective factors. Palmitoleic acid remained a risk factor for AF (OR = 1.35, 95% CI = 1.19-1.50) after Bonferroni correction, whereas α/γ-linolenic acid remained a protective factor (odds ratio [OR] = 0.94, 95% confidence interval [95% CI] = 0.89-0.98). GC-MS analysis showed that palmitoleic (p = 0.028) and stearic (p = 0.005) acid levels were significantly higher in the AF group than in the non-AF group. Receiver operating characteristics curve analysis for palmitoleic acid showed an area under the curve of 0.727, with a sensitivity and specificity of 100% and 50%, respectively. CONCLUSION: Palmitoleic acid was identified as a potential risk factor for AF, while α/γ-linolenic acid showed a protective effect in the MR analysis. GC-MS validation further demonstrated that palmitoleic acid levels were elevated in patients with AF. © 2026 S. Karger AG, Basel.

Bone morphogenetic proteins (BMPs) participate in the energy metabolism. BMP receptor type 2 (BMPR2) is expressed in the liver. Whether BMPR2 is involved in the pathophysiology of nonalcoholic fatty liver disease (NAFLD) has not been studied. In this study, we analyzed the RNA-sequence data of several patient cohorts and found that BMPR2 expression decreases at the stages of advanced fibrosis. A mouse model featuring BMPR2 knockout demonstrate that BMPR2 knockout in the liver produces profibrotic effect upon long-term high-fat and high-fructose (HFF) diet challenge. BMP signaling promotes biosynthesis of unsaturated fatty acids, which is repressed under BMPR2 knockout condition. The most affected unsaturated fatty acid, palmitoleic acid (POA), is found to activate CD169 macrophages. Moreover, CD169 macrophages is revealed to have high levels of lysosomal enzyme along with matrix metalloproteinase 8, which degrades collagen and alleviates fibrosis. Our study demonstrates that BMPR2 influences over the progression of liver fibrosis induced by the HFF diet through fatty acid-regulated CD169 macrophages. POA-primed macrophages might be a potential therapeutic strategy for the treatment of liver fibrosis. © 2026. The Author(s).

Acute appendicitis is commonly treated by appendectomy, which may be costly, risky, or unsuitable for some patients. Anecdotal reports suggest that Anthocleista djalonensis is a traditional, cost-effective remedy for this inflammatory condition, yet potential underlying mechanisms remain poorly understood. This study combined gas chromatography-mass spectrometry (GC-MS) and computational approaches to characterize the stem bark extract of A. djalonensis and explore its mechanistic relevance to acute appendicitis. GC-MS analysis identified methyl palmitate, methyl oleate, methyl stearate, and palmitoleic acid in the volatile oil of the stem bark. These compounds, together with phytoconstituents retrieved from the literature and public databases, were subsequently screened using established oral bioavailability and drug-likeness criteria to determine their inclusion in network pharmacology analysis. Network and functional enrichment analyses suggest that A. djalonensis bioactive compounds, including quercetin, resveratrol, pentadecanoic, palmitoleic, and caffeic acids, may exert multi-target regulation of inflammatory and metabolic pathways. These pathways include PI3K/Akt, HIF-1, endocrine resistance, and EGFR signaling, involving AKT1, GAPDH, TNF, and EGFR, among other core targets. Despite limitations inherent in computational prediction and limited experimental validation, these findings offer valuable insights to advance understanding of A. djalonensis's ethnomedicinal use in treating acute appendicitis. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2026. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

This research aimed to systematically investigate the regulatory effects of six key fatty acids and rationally designed a functional fatty acid component (FFAC) to alleviate palmitic acid (PA)-induced glycolipid metabolism disorders and insulin resistance (IR) in HepG2 cells and Western diet-induced IR in the C57BL/6 mice model. In vitro experiments showed that saturated fatty acids such as PA and stearic acid (SA) induced concentration-dependent cytotoxicity and IR in HepG2 cells, while unsaturated fatty acids, including palmitoleic acid (POA), oleic acid (OA), linoleic acid (LA), and α-linolenic acid (ALA), enhanced cell viability and exerted protective effects. Based on the principle of balanced fatty acid ratio and the obtained cell experimental results, FFAC was designed as PA:SA:POA:OA:LA:ALA = 4:1:1:4:4:1 and formulated using dietary oils. In vivo, a 13-week dietary intervention revealed that FFAC substitution mitigated Western diet-induced weight gain, systemic IR, serum lipid disorders, and hepatic steatosis in mice. Mechanistically, FFAC restored the IRS1/PI3K/Akt/GSK3β insulin signaling pathway in HepG2 cells and reshaped gut microbiota by enriching beneficial genera such as Akkermansia. These findings demonstrated that FFAC effectively alleviates diet-induced metabolic disorders through multiple pathways, highlighting the potential of rationally designed dietary fatty acid compositions in managing metabolic disorders.

Sickness-associated anorexia (SAA) is a common symptom during bacterial infections in fish that complicates treatment due to reduced oral drug uptake and efficacy. While current research has largely focused on cytokine-mediated pathways affecting the central nervous system, the role of gut microbiota and metabolic homeostasis in SAA remains poorly understood. Here, we used an integrated approach including single-cell sequencing, 16S rDNA sequencing, and metabolomics to investigate appetite suppression in Epinephelus coioides infected with Pseudomonas plecoglossicida, a non-intestinal pathogen. Infection severely disrupted intestinal epithelial turnover and homeostasis, marked by loss of epithelial and goblet cells, and altered microbiota composition. Although no key bacteria linked to tryptophan-derived metabolite metabolism were detected, we identified three microbiota members and several metabolites, including cimetidine, palmitoleic acid (PA), 16-hydroxypalmitate, imidazoleacetic acid, quinolinic acid, and glycerol, associated with homeostasis disruption. Notably, PA depletion correlated strongly with reduced intestinal cells and upregulation of senescence and apoptosis genes, leading to SAA. Exogenous PA supplementation mitigated infection-induced appetite loss, restored microbial balance, and improved epithelial integrity. These findings reveal that non-intestinal pathogens can disturb gut homeostasis and promote SAA via reduced PA levels, suggesting dietary PA supplementation as a potential therapeutic strategy to enhance appetite and recovery in infected fish. © 2026. The Author(s).