Gymnema Sylvestre

There is a growing interest in the considerable health benefits of Gymnema Sylvestre (GS) supplementation, as some studies have reported that it may improve cardiometabolic risk factors. However, the widespread impact of GS supplementation on the parameters mentioned above is not fully resolved. Consequently, this study aimed to examine the effects of GS supplementation on lipid profile, glycemic control, blood pressure, and anthropometric indices in adults. Eligible randomized controlled trials (RCT), published up to November 2021, were identified through PubMed, Scopus, and ISI Web of Science databases. Six studies were included and analyzed using a random-effects model to calculate weighted mean differences (WMDs) with 95% confidence intervals (CI). All studies were conducted in adults that used a GC supplement (>1 week) and assessed our selected cardiovascular risk factors. Outcomes revealed that GS supplementation significantly decreased triglyceride (p < .001), total cholesterol (p < .001), low-density lipoprotein (p < .001), fasting blood sugar (p < .001), and diastolic blood pressure (p = .003). Some limitations, including notable heterogeneity, low quality of studies, and lack of diversity among research participants, should be considered when interpreting our results. Our outcomes suggest that GS supplementation may improve cardiovascular risk factors. Future large-high-quality RCTs with longer duration and various populations are needed to firmly establish the clinical efficacy of the plant. © 2022 John Wiley & Sons Ltd.

This systematic review and meta-analysis aims to find the effect of Gymnema sylvestre (GS) supplementation on glycemic control in type-2 diabetes mellitus (T2DM). PubMed, Cochrane library, Google Scholar, and Science Direct were searched from inception to June 2020 to identify the studies that reported GS supplementation on glycemic parameters. Standardized mean difference (SMD) was calculated by comparing the post-intervention data with baseline data. SMDs with 95% confidence intervals (CIs) were pooled using a random-effects model. Our meta-analysis consisting of 10 studies with a total of 419 participants showed that GS supplementation significantly reduces fasting blood glucose (FBG) (SMD 1.57 mg/dl, 95% CI 2.22 to -0.93, p < .0001, I2 90%), postprandial blood glucose (PPBG) (SMD 1.04 mg/dl, 95% CI 1.53 to -0.54, p < .0001, I2 80%), and glycated haemoglobin (HbA1c) (SMD 3.91, 95% CI 7.35 to -0.16%, p < .0001, I2 99%) compared to baseline. Further, our study also found that GS significantly reduces triglycerides (SMD 1.81 mg/dl, 95% CI 2.95 to -0.66, p < .0001, I2 : 96%), and total cholesterol (SMD 4.10 mg/dl, 95% CI 7.21 to -0.99, p < .0001, I2 : 98%) compared to baseline. Our study shows that GS supplementation is effective in improving glycemic control and reducing lipid levels in T2DM patients and suggests that such supplementation might be used as an effective therapy for the management of T2DM and its associated complications to an extent. © 2021 John Wiley & Sons Ltd.

Background/Objectives: Excessive intake of sugar-sweetened food (SSF) increases obesity risk. Various psychological, physiological, and environmental factors may drive high consumption of SSF. Due to blocking sweet tastes, the herb Gymnema sylvestre (GS) has been shown to reduce SSF consumption, but its impact on motivation to eat SSF is unknown. This research aimed to qualitatively investigate adults' perceptions regarding effects of GS on their motivation to eat SSF when administered systematically (three times/day in-between meals, i.e., GS-SYS treatment) or ad libitum (up to six times/day at participants' discretion, i.e., GS-ADLIB) over 14 days, compared to placebo (taste-matched mint; PLAC-SYS). Methods: This study represents the qualitative investigation of a placebo-controlled randomised cross-over trial, conducted as three 14-day phases. The qualitative investigation included interviews at baseline and three post-testing phases. Seven participants (mean age 34.7 ± 13.8 years; two males, five females) agreed to participate. Twenty-eight interviews (across phases) were thematically analysed using NVivo software, identifying themes and highlighting changes in motivation to eat SSFs across the study. Results: The GS-SYS and GS-ADLIB treatments made SSFs unpleasant to eat and increased mindful eating, subsequently increasing motivation to avoid SSFs. External factors could increase or decrease motivation, depending on individual circumstances. Participants preferred GS-SYS and GS-ADLIB over PLAC-SYS, feeling it was more effective at changing behaviours related to SSF intake. Self-control over SSF intake changed during the study, mostly due to external factors, and in part GS-ADLIB. Conclusions: Participants found both GS administrations successful as motivation to avoid SSF; GS-ADLIB was considered most effective.

Gymnema sylvestre (GS) contains gymnemic acids which can reversibly suppress sweet taste responses. This randomised crossover study aimed to investigate whether supplemental GS use can reduce sugar cravings, sweet food desire and consumption among adults that identify as high sweet food consumers (having a 'sweet tooth'). Participants were told three different mints were trialled to avoid bias. On day zero, 32 healthy participants underwent baseline sensory testing for sweet taste perception using the placebo mint (PLAC). Participants were then randomised into the two intervention groups. On day 15 and 30, participants underwent further sensory testing using the GS mints, before embarking on each 14-day intervention using the GS mints, using either a systematic (at 3 specified times/day; SYS) or ad libitum (up to 6 mints/day at times of their choosing; AD-LIB) regimen, as assigned. On day 30, participants swapped over to the other intervention (using the other regimen), completing final data collection in day 45. At all visits participants completed questionnaires (food frequency questionnaire, beverage questionnaire and cravings questionnaire), anthropometric measures, and sensory testing. Sensory testing was not required for day 45. The AD-LIB condition reduced daily sugar-sweetened beverages (SSB) intake by 42% relative to PLAC (p = 0.015) and reduced overall sugar cravings by 28% relative to PLAC (p = 0.045). Both AD-LIB and SYS reduced pleasantness ratings (p < 0.005) and desire (p = 0.005) for more chocolate. Using GS with an ad libitum regimen reduced sugar cravings and changed sweet food desire and consumption in people identifying as having a sweet tooth.

A study on 81 individuals (18-75 years old) with mildly impaired fasting blood glucose (FBG) concentrations (98-125 mg/dL) was undertaken to investigate the tolerability of a food supplement (FS) based on Zea mays and Gymnema sylvestre extracts, zinc, and chromium and its efficacy on glucose and lipid metabolism. The subjects were randomized into three groups (27 in each group) and supplemented with one or two tablet(s)/day of FS (groups 1 and 2, respectively), or two tablets/day of placebo (group 3). Blood sampling was carried out at baseline (t0) and after a 3-month treatment (t1), and biochemical parameters associated with glucose and lipid metabolism and kidney and liver toxicity were evaluated. Compared to the placebo, FBG and glycated haemoglobin (HbA1c) were significantly (p < 0.001) reduced in group 1 subjects. In contrast, at the doses of one and two tablet(s)/day, the FS exerted no effect on the other parameters examined. We conclude that in subjects with slightly impaired FBG, ingestion of a FS based on Z. mays and G. sylvestre extracts, zinc, and chromium over 3 months lowers FBG and modulates glucose homeostasis by improving glucose metabolism. These beneficial effects occur in the absence of biochemical evidence of kidney and liver toxicity.

Gymnema sylvestre (GS) and berberine (BBR) are natural products that have demonstrated therapeutic potential for the management of obesity and its comorbidities, as effective and safe alternatives to synthetic drugs. Although their anti-obesogenic and antidiabetic properties have been widely studied, comparative research on their impact on the gene expression of adipokines, such as resistin (Res), omentin (Ome), visfatin (Vis) and apelin (Ap), has not been reported. METHODOLOGY: We performed a comparative study in 50 adult Mexican patients with obesity treated with GS or BBR for 3 months. The baseline and final biochemical parameters, body composition, blood pressure, gene expression of Res, Ome, Vis, and Ap, and safety parameters were evaluated. RESULTS: BBR significantly decreased (p < 0.05) body weight, blood pressure and Vis and Ap gene expression and increased Ome, while GS decreased fasting glucose and Res gene expression (p < 0.05). A comparative analysis of the final measurements revealed a lower gene expression of Ap and Vis (p < 0.05) in patients treated with BBR than in those treated with GS. The most frequent adverse effects in both groups were gastrointestinal symptoms, which attenuated during the first month of treatment. CONCLUSION: In patients with obesity, BBR has a better effect on body composition, blood pressure, and the gene expression of adipokines related to metabolic risk, while GS has a better effect on fasting glucose and adipokines related to insulin resistance, with minimal side effects.

Gymnemic-acids (GA) block lingual sweet taste receptors, thereby reducing pleasantness and intake of sweet food. Objective: To examine whether a 14-day gymnema-based intervention can reduce sweet foods and discretionary sugar intake in free-living adults. Healthy adults (n = 58) were randomly allocated to either the intervention group (INT) or control group (CON). The intervention comprised of consuming 4 mg of Gymnema sylvestre containing 75% gymnema acids, a fibre and vitamin supplement, and an associated healthy-eating guide for 14 days; participants in the CON group followed the same protocol, replacing the GA with a placebo mint. Amount of chocolate bars eaten and sensory testing were conducted before and after the 14-day intervention (post-GA or placebo dosing on days zero and 15, respectively). Food frequency questionnaires were conducted on days zero, 15 and after a 28-day maintenance period to examine any changes in intake of sweet foods. A range of statistical procedures were used to analyse the data including Chi square, t-test and two-way analysis of variance. Post dosing, INT consumed fewer chocolates (2.65 ± 0.21 bars) at day zero than CON (3.15 ± 0.24 bars; p = 0.02); there were no differences between groups at day 15 (INT = 2.77 ± 0.22 bars; CON = 2.78 ± 0.22 bars; p = 0.81). At both visits, a small substantive effect (r < 0.3) was observed in the change in pleasantness and desire ratings, with INT showing a slight increase while CON showed a small decrease over the 14-day period. No differences were found in the intake of 9 food categories between groups at any timepoint. There were no differences in consumption of low sugar healthy foods between visits, or by group. The 14-day behavioural intervention reduced pleasantness and intake of chocolate in a laboratory setting. There was no habituation to the mint over the 14-day period. This study is the first to investigate the effect of longer-term gymnema acid consumption on sweet food consumption outside of a laboratory setting; further research is needed to assess how long the effect of the 14-day intervention persists.

Objectives: Prediabetes is a major public health concern. Different plant extracts are used in homeopathy as mother tinctures (MTs) for the treatment of prediabetes as an adjunct to individualized homeopathic medicines (IHMs); however, their effectiveness remains under-researched. Design: Open-label, randomized (1:1), active-controlled, pragmatic, exploratory trial. Setting: Mahesh Bhattacharyya Homoeopathic Medical College and Hospital, Howrah, West Bengal, India. Subjects: Eighty-nine patients with prediabetes. Interventions: Group 1 (n = 45; IHMs plus any one of the following MTs: Cephalandra indica, Gymnema sylvestre, and Syzygium jambolanum; experimental/verum) versus Group 2 (n = 44; IHMs only; control). Outcome measures: Blood parameters, including-the fasting blood sugar (FBS) level, blood sugar level 2 h after ingestion of 75 g of glucose (oral glucose tolerance test [OGTT] result), and glycosylated hemoglobin percentage (HbA1c%), and symptoms, including the Diabetes Symptom Checklist-Revised (DSC-R) score; all of them were measured at baseline and after 3 and 6 months. Results: Although recruitment of 140 patients was initially planned, the target sample size could not be achieved because of coronavirus disease pandemic-related restrictions. Only 89 patients could be enrolled, and the trial had to be terminated prematurely owing to the time constraints of the project. The data of 82 patients (Group 1, n = 40; Group 2, n = 42) were analyzed using a modified intention-to-treat approach. Improvements in all outcomes were greater in Group 1 than in Group 2, but without a significant difference: FBS level (F1, 80 = 4.095, p = 0.046), OGTT result (F1, 80 = 2.399, p = 0.125), HbA1c% (F1, 80 = 1.612, p = 0.208), and DSC-R score (F1, 80 = 0.023, p = 0.880). Conclusions: A promising but nonsignificant trend favored the combination of MTs and IHMs compared with IHMs alone among the patients with prediabetes, especially in FBS. Therefore, further studies are required. Clinical Trial Registration Number: CTRI/2018/08/015319; secondary identifier (UTN): U1111-1218-6016.

Caesalpinia bonduc (L.) and Gymnema sylvestre (Retz.) are traditional remedies for diabetes management. This study explored their potential synergistic effects in alloxan (ALX)-induced diabetic Wistar rats. Aqueous-methanol extracts of C. bonduc seed kernels (C. bonduc extract [CBE]) and G. sylvestre leaves (G. sylvestre extract [GSE]) were phytochemically characterized. In vivo, experimental diabetic rats were treated with metformin (MET; 150 mg/kg), CBE (400 mg/kg), GSE (400 mg/kg), and a combined dose of CBE + GSE at 400 mg/kg (200 mg/kg of each plant extract) for 28 days. Biochemical analyses revealed significant antioxidant and hypoglycemic effects of the extracts, with the combined treatment (CBE + GSE) demonstrating superior outcomes. This combination improved fasting blood glucose, insulin, glycated hemoglobin A1c (HbA1c), and oxidative stress markers, including superoxide dismutase (SOD) and catalase (CAT) activities. Additionally, CBE + GSE significantly modulated insulin secretion and stress-related gene expression while downregulating the c-Jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK) pathway. Histopathological results further confirmed the enhanced antidiabetic effects of the combination therapy. These findings suggest that the combined use of C. bonduc and G. sylvestre offers a promising therapeutic approach for diabetes management due to the complementary pharmacological activities of their phytochemicals. © 2025 Wiley‐VHCA AG, Zurich, Switzerland.

Prolonged insulin resistance is considered one of the reasons for Type 2 Diabetes Mellitus. Upregulation of Protein tyrosine phosphatase 1B (PTP1B), a negative regulator of insulin signalling, has been well studied as a key regulator in prognosis to insulin resistance. It has been widely studied as a desirable molecular therapeutic target. The study aimed to evaluate the efficacy of leaf extract of the medicinal plants Silybum marianum on the inhibition of PTP1B activity. It also explored the synergistic effect with extracts of Gymnema sylvestre (leaves), Momordica charantia (seeds), and Trigonella foenum graecum (seeds). The S. marianum leaves showed dose-dependent inhibition of PTP1B ranging from 9.48-47.95% (25-1000 μg mL-1). Assay with individual plant extracts showed comparatively lesser inhibition of PTP1B as compared to metformin as a control (38% inhibition). However, a synergistic effect showed nearly 45% PTP1B inhibition (higher than metformin) after the assay was done with selected four plant extracts in combination. The effect of leaf extracts of S. marianum was studied for glucose uptake efficiency in yeast cell lines which was found to be increased by 23% as compared to the control (without extract). Metformin improves glucose upake by yeast cells by ~15-31%. GC-MS analysis revealed 23 phytochemicals, some of which possessed anti-diabetic properties. A dose-dependent increase in antioxidant activity of S. marianum leaves extracts was observed (40-53%). The findings of the study highlighted the presence of various phytochemicals in leaves extracts that are effective against PTP1B inhibition and may help in reinvigorating drug development.

BACKGROUND AND OBJECTIVES: Gymnema sylvestre R. Br. is a well-known Indian medicinal herb. Gymnemic acids are pentacyclic triterpenes saponins and active phytoconstituents of Gymnema sylvestre. The study aimed at evaluation of the in vitro rat liver cytochrome P450 (CYP) inhibition potential of extracts and total gymnemic acid (TA)-enriched fractions from G. sylvestre. METHODS: Standardization of G. sylvestre [ethanolic (EL), hydroethanolic (HE), total acid of ethanolic (TAE), total acid of hydroethanolic (TAHE) and total acid of aqueous (TAAQ) extract] was done with respect to deacyl gymnemic acid (DAGA), using reverse phase-high performance liquid chromatography (RP-HPLC). Total triterpenoid content was determined by vanillin perchloric acid assay. RESULTS: Total triterpene content was found to be the highest in TAAQ (59.86 ± 0.005% w/w) and TAE (49.77 ± 0.009% w/w). TAAQ showed IC50 ≤ 50 µg/ml for all selected CYP activities. Testosterone 6β-hydroxylation was strongly inhibited by TAE (IC50: 15.48 ± 2.13 µg/ml) and was moderately by TAAQ and EL with IC50 ≥ 50 µg/ml. Flurbiprofen 4'-hydroxylation was subject to strong, weak and moderate inhibition by TAAQ (IC50: 34.67 ± 1.38 µg/ml), TAE (IC50: ≥ 50 µg/ml) and EL (IC50: > 50 µg/ml), respectively. Dextromethorphan O-demethylation was inhibited by TAHE and TAAQ. CONCLUSIONS: In vitro inhibition studies suggested that TA strongly inhibits activity of selected CYP. This inhibition may possibly be due to triterpenoids and gymnemic acids that have been reported to be present in it. Data also suggest a potential for possible in vivo herb-drug interactions involving G. sylvestre and other medications that are metabolized by the same CYP.

Gymnema sylvestre, important Indian traditional herbal medicine has been used for diabetes from several years and marketed as single or multi-herb formulations globally. People are consuming G. sylvestre along with conventional hypoglycemic drugs. Therefore, there is need of evidence based assessment of risk versus benefits when G. sylvestre co-administered with conventional oral hypoglycemic drugs. In present investigation, pharmacodynamics and pharmacokinetic interactions with oral hypoglycemic drug, glimepiride (GLM) was studied in streptozotocin (STZ) induced diabetic rats. A specific and rapid HPLC-ESI-MS/MS method was established for simultaneous quantification of GLM and gymnemagenin (GMG) in rat plasma. Pharmacokinetic and pharmacodynamic interaction studies were carried out in STZ induced diabetic rats after concomitant administration of 400 mg/kg of G. sylvestre extract and 0.8 mg/kg of GLM for 28 days. The developed HPLC-ESI-MS/MS method was rapid, specific, and precise. Con-comitant oral administration of G. sylvestre extract (400 mg/kg) and GLM (0.8 mg/kg) in diabetic rats for 28 days showed beneficial pharmacodynamic interactions whereas no major alterations in the pharmacokinetics parameters of GLM and GMG were observed. This interaction demonstrated in animal model implies that significant clinical outcome might occur during concomitant administration of G. sylvestre extract and GLM especially in diabetic patients and warrants further studies in the same set up.

OBJECTIVE: Consuming botanical dietary supplements or herbal drugs along with prescription drugs may lead to potential pharmacokinetic-pharmacodynamic (PK-PD) herb-drug interactions (HDI). The present study focuses on the importance of and novel approach for assessing HDI in integrative medicine with case examples of two frequently-used Ayurvedic Rasayana botanicals. METHODS: The aqueous extracts of Asparagus racemosus (ARE) and Gymnema sylvester (GSE) were prepared as per Ayurvedic Pharmacopoeia of India. Chemoprofiling of these extracts was done using high-performance liquid chromatography (HPLC). Additionally, ARE was characterized for the presence of shatavarins IV and I using HPLC & mass spectroscopy respectively. Effects of ARE and GSE were investigated on rat liver microsome using testosterone probe drug assay. The changes in formation of metabolite (6-β hydroxy testosterone) were monitored on incubation of testosterone alone, testosterone with ketoconazole, ARE and GSE using HPLC. Half inhibitory concentration (IC50) was used to predict plausible HDI. RESULTS: ARE and GSE showed no inhibition with IC50 values >1 000 μg/mL while the standard inhibitor ketoconazole completely abolished CYP3A4-dependent activity at 0.531 μg/mL and IC50 was found to be 0.036 μg/mL. CONCLUSION: ARE and GSE prepared as per Ayurvedic Pharmacopoeia of India were found to be safe for CYP3A4-mediated inhibitory HDI in rats. Our in vitro study suggests the need of further in vivo investigation for HDI in order to provide clinical relevance.

A sensitive and rapid high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been developed and validated for the determination of gymnemagenin (GMG), a triterpene sapogenin from Gymnema sylvestre, in rat plasma using withaferin A as the internal standard (IS). Plasma samples were simply extracted using liquid-liquid extraction with tetra-butyl methyl ether. Chromatographic separation was performed on Luna C(18) column using gradient elution of water and methanol (with 0.1% formic acid and 0.3% ammonia) at a flow rate of 0.8 mL/min. GMG and IS were eluted at 4.64 and 4.36 min, ionized in negative and positive mode, respectively, and quantitatively estimated using multiple reaction monitoring (MRM) mode. Two MRM transitions were selected at m/z 505.70 → 455.5 and m/z 471.50 → 281.3 for GMG and IS, respectively. The assay was linear over the concentration range of 5.280-300.920 ng/mL. The mean plasma extraction recoveries for GMG and IS were found to be 80.92 ± 8.70 and 55.63 ± 0.76%, respectively. The method was successfully applied for the determination of pharmacokinetic parameters of GMG after oral administration of G. sylvestre extract.

The sweetness-suppressing polypeptide gurmarin isolated from Gymnema sylvestre consists of 35 amino acid residues and contains three intramolecular disulfide bonds. Nuclear magnetic resonance analysis showed that the hydrophobic side chains of Tyr-13, Tyr-14, Trp-28, and Trp-29 in gurmarin are oriented outwardly. Together with the hydrophobic side chains of Leu-9, Ile-11, and Pro-12, they form a hydrophobic cluster, and therefore these hydrophobic groups are assumed to act as the site for interaction with the receptor protein. To examine the roles of these hydrophobic amino acids, they were replaced by Gly. The resulting [Gly13,14,28,29] gurmarin and [Gly9,11,13,14,28,29]-gurmarin did not suppress the responses to sucrose, glucose, fructose, or Gly. This result strongly suggests that these hydrophobic amino acids are involved in the interaction with the receptor protein.

Considerable recent attention has been focused on naturally occurring compounds with taste-modifying activity, which are of potential use in both dietary sweetness management and in gaining a better understanding of the sweet taste sensation. This review summarizes information on the phytochemistry and biological activity of more than 40 triterpenoid sweetness inhibitors that have been isolated from the leaves of three medicinal plants, namely, Gymnema sylvestre R.Br. (Asclepiadaceae), Ziziphus jujuba P. Miller (Rhamnaceae), and Hovenia dulcis Thunb. (Rhamnaceae).

The inhibitory effects of gurmarin (a peptide isolated from the leaves of Gymnema sylvestre) on sweet taste responses were studied by examining the chorda tympani nerve responses to various taste substances before and after lingual treatment with gurmarin in C57BL and BALB mice. Treatment with gurmarin at 3 micrograms/ml or more selectively suppressed responses to sucrose without affecting responses to NaCl, HCl, and quinine in C57BL mice, whereas gurmarin at 100 micrograms/ml did not significantly suppress sucrose responses in BALB mice. Responses to various sweet substances in C57BL mice decreased to approximately 45-75% of control after gurmarin, and the suppressive effect of gurmarin was reversible. The profile of the residual responses of C57BL mice to various sweeteners after gurmarin was almost identical to that of BALB mice, which was hardly affected by gurmarin. These results strongly suggest that there are at least two types of sweet taste receptors in mice, gurmarin-sensitive and -insensitive. Probably, C57BL and BALB mice share an identical gurmarin-insensitive receptor, and C57BL mice also have a gurmarin-sensitive receptor.

BACKGROUND: The increasing incidence of diabetes worldwide has urged researchers to explore novel antidiabetic agents from natural products. Ethnomedicinal field studies on diabetes have expanded across the globe, documenting large numbers of folk medicinal plants against diabetes. Nonetheless, a systematic review of these surveys has not been conducted so far. This study documents the medicinal plants traditionally used globally for managing diabetes. METHODS: Key databases including Sciencedirect, Medline/PubMed, and Google Scholar were scrutinized. The Plant List and The International Plant Names Index (IPNI) were used to validate the scientific plant names. RESULTS: 2004 traditionally used plants belonging to 1112 genera and 197 families were reported across 92 countries for the management of diabetes. Leguminosae (105 genera and 193 species), Compositae (97 genera and 188 species), and Lamiaceae (47 genera and 121 species) were the main plant families reported. Momordica charantia L., Syzygium cumini (L.) Skeels, Allium sativum L., Azadirachta indica A.Juss., Catharanthus roseus (L.) G.Don, Olea europaea L., Trigonella foenum-graecum L., Gymnema sylvestre (Retz.) R.Br. ex Sm., Aloe vera (L.) Burm.f., and Allium cepa L were the species mostly reported. Indeed, the antidiabetic properties of these main species have been evidenced by experimental studies. Several antidiabetic compounds acting via different mechanisms have been identified, including momordicoside, karaviloside, cucurbitacin, charantin, and charantoside from M. charantia, cuminoside from S. cumini, S-allyl cysteine sulfoxide from A. sativum, limonoids from A. indica, alkaloids including vindoline, vindolidine, vindolicine and vindolinine from C. roseus, oleuropein and oleanolic acid from O. europaea, flavone C-glycosides such as vicenin-1, isoschaftoside, and schaftoside from T. foenum-graecum seeds, gymnemosides, gymnemagenin, and pregnane glycosides from G. sylvestre, chysalodin from A. vera, and quercetin from A. cepa. CONCLUSION: This review is the first to provide a compiled list of traditional medicinal plants used worldwide against diabetes.

The prevalence of obesity is associated with many health-related problems. Currently, more than 300 million people are considered to be obese. According to the World Health Organization (WHO), by 2030, 87 and 439 million people will be affected in India and the world, respectively. Today, herbal medicines are gaining interest in the treatment of obesity and diabetes, because of their minimal side effects. Gymnemic acid - an active component isolated from Gymnema sylvestre - has anti-obesity and antidiabetic properties, decreases body weight and also inhibits glucose absorption. Several components extracted from Gymnema prevent the accumulation of triglycerides in muscle and liver, and also decrease fatty acid accumulation in the circulation. In this paper, an attempt has been made to review the effects of various extracts from Gymnema sylvestre in the regulation of carbohydrate and lipid metabolism in both animal and clinical studies. © 2013 Society of Chemical Industry.

OVERVIEW: As obesity has reached epidemic proportions, the management of this global disease is of clinical importance. The availability and popularity of natural dietary supplements for the treatment of obesity has risen dramatically in recent years. AIMS: The aim of this paper was to assess the current evidence of commonly available natural supplements used to suppress appetite for obesity control and management in humans using a systematic search of clinical trials meeting an acceptable standard of evidence. METHODS: The electronic databases PubMed, Web of Science, Google Scholar, ScienceDirect, and MEDLINE with full text (via EBSCOHost) were accessed during late 2012 for randomized controlled clinical trials (RCTs) using natural plant extracts as interventions to treat obesity through appetite regulation. A quality analysis using a purpose-designed scale and an estimation of effect size, where data were available, was also calculated. The inclusion criteria included the following: sample participants classified as overweight or obese adults (aged 18-65 years), randomized, double blind, controlled design, suitable placebo/control intervention, sample size >20, duration of intervention >2 weeks, have measurable outcomes on appetite or food intake and anthropometry, and full paper in English. RESULTS: There were 14 studies that met the inclusion criteria. The findings from published double blind RCTs revealed mostly inconclusive evidence that plant extracts are effective in reducing body weight through appetite suppression. Caralluma fimbriata extract and a combination supplement containing Garcinia cambogia plus Gymnema sylvestre were the only exceptions. CONCLUSION: According to the findings from this systematic review, the evidence is not convincing in demonstrating that most dietary supplements used as appetite suppressants for weight loss in the treatment of obesity are effective and safe. A balance between conclusive findings by double blind RCTs and advertisement is required to avoid safety concerns and dissatisfaction from consumers.

An evidence-based systematic review of gymnema (Gymnema sylvestre R. Br.), including written and statistical analysis of scientific literature, expert opinion, folkloric precedent, history, pharmacology, kinetics/dynamics, interactions, adverse effects, toxicology, and dosing.

Across the globe, there are an estimated 150 million people suffering from diabetes mellitus. Each of these people is at increased risk of developing a number of complications, each of which are associated with a reduction in quality of life and an increase in individual morbidity and mortality. However, despite these psychosocial implications, as well as the financial burden associated with the management of the disease, existing treatment options are costly, and have limited, palliative effects. One treatment that is emerging as a potential panacea for the management of diabetes is Gymnema sylvestre. Yet, what evidence is there to support the use of this extract? In order to answer this question, a systematic review of the literature and a discussion of the best available evidence on gymnema are needed. The findings of such a review are presented in this paper.

OBJECTIVE: To conduct a systematic review of the published literature on the efficacy and safety of herbal therapies and vitamin/mineral supplements for glucose control in patients with diabetes. RESEARCH DESIGN AND METHODS: We conducted an electronic literature search of MEDLINE, OLDMEDLINE, Cochrane Library Database, and HealthSTAR, from database inception to May 2002, in addition to performing hand searches and consulting with experts in the field. Available clinical studies published in the English language that used human participants and examined glycemic control were included. Data were extracted in a standardized manner, and two independent investigators assessed methodological quality of randomized controlled trials using the Jadad scale. RESULTS: A total of 108 trials examining 36 herbs (single or in combination) and 9 vitamin/mineral supplements, involving 4,565 patients with diabetes or impaired glucose tolerance, met the inclusion criteria and were analyzed. There were 58 controlled clinical trials involving individuals with diabetes or impaired glucose tolerance (42 randomized and 16 nonrandomized trials). Most studies involved patients with type 2 diabetes. Heterogeneity and the small number of studies per supplement precluded formal meta-analyses. Of these 58 trials, the direction of the evidence for improved glucose control was positive in 76% (44 of 58). Very few adverse effects were reported. CONCLUSIONS: There is still insufficient evidence to draw definitive conclusions about the efficacy of individual herbs and supplements for diabetes; however, they appear to be generally safe. The available data suggest that several supplements may warrant further study. The best evidence for efficacy from adequately designed randomized controlled trials (RCTs) is available for Coccinia indica and American ginseng. Chromium has been the most widely studied supplement. Other supplements with positive preliminary results include Gymnema sylvestre, Aloe vera, vanadium, Momordica charantia, and nopal.