Pilot study: Hypoglycemic and antiglycation activities of bitter melon (Momordica charantia L.) in type 2 diabetic patients

Therapeutic Potential of Momordicine I from Momordica charantia: Cardiovascular Benefits and Mechanisms

Momordica charantia (bitter melon), a traditional medicinal plant, has been demonstrated to have potential in managing diabetes, gastrointestinal problems, and infections. Among its bioactive compounds, momordicine I, a cucurbitane-type triterpenoid, has attracted attention due to its substantial biological activities. Preclinical studies have indicated that momordicine I possesses antihypertensive, anti-inflammatory, antihypertrophic, antifibrotic, and antioxidative properties, indicating its potential as a therapeutic agent for cardiovascular diseases. Its mechanisms of action include modulating insulin signaling, inhibiting inflammatory pathways, and inducing apoptosis in cancer cells. The proposed mechanistic pathways through which momordicine I exerts its cardiovascular benefits are via the modulation of nitric oxide, angiotensin-converting enzymes, phosphoinositide 3-kinase (PI3K)/ protein kinase B (Akt), oxidative stress, apoptosis and inflammatory pathways. Furthermore, the anti-inflammatory effects of momordicine I are pivotal. Momordicine I might reduce inflammation through the following mechanisms: inhibiting pro-inflammatory cytokines, reducing adhesion molecules expression, suppressing NF-κB activation, modulating the Nrf2 pathway and suppressing c-Met/STAT3 pathway. However, its therapeutic use requires the careful consideration of potential side effects, contraindications, and drug interactions. Future research should focus on elucidating the precise mechanisms of momordicine I, validating its efficacy and safety through clinical trials, and exploring its pharmacokinetics. If proven effective, momordicine I could considerably affect clinical cardiology by acting as a novel adjunct or alternative therapy for cardiovascular diseases. To date, no review article has been published on the role of bitter-melon bioactive metabolites in cardiovascular prevention and therapy. The present work constitutes a comprehensive, up-to-date review of the literature, which highlights the promising therapeutic potential of momordicine I on the cardiovascular system and discusses future research recommendations.

Effects of Momordica charantia L. supplementation on glycemic control and lipid profile in type 2 diabetes mellitus patients: A systematic review and meta-analysis of randomized controlled trials

Background and aims

Momordica charantia L. (M. charantia) has been traditionally utilized as a medicinal intervention for managing type 2 diabetes mellitus (T2DM). The current study was designed to offer a GRADE-assessed systematic review and meta-analysis of randomized controlled trials (RCTs) examining the impact of M. Charantia intake on glycemic indexes and the lipid profile of patients with T2DM.

Methods

A comprehensive search was conducted across several databases, including PubMed, EMBASE, Web of Science, and Cochrane Library, from the inception of each database until April 22, 2023. The Hartung-Knapp adjustment was applied to ensure conservative summary estimates with broad confidence intervals.

Results

A total of eight trials involving 423 patients with T2DM were included in this study. Compared to the control group, the intake of M. charantia supplementation resulted in significant reductions in fasting blood glucose (FBG) (WMD: -0.85 mmol/L; 95%CI: -1.44, -0.26; p = 0.005; I2 = 73.4 %), postprandial glucose (PPG) (WMD: -2.28 mmol/L; 95%CI: -3.35, -1.21; p = 0.000; I2 = 66.9 %), glycosylated hemoglobin A1c (HbA1c) (WMD: -0.38 %; 95%CI: -0.53, -0.23; p = 0.000; I2 = 37.6 %), and total cholesterol (TC) (WMD: -0.38 mmol/L; 95%CI: -0.70, -0.07; p = 0.017; I2 = 63.6 %). These results remained statistically significant even after applying the Hartung-Knapp adjustment. However, no significant differences were observed in terms of triglyceride (TG), high-density lipoprotein (HDL), and low-density lipoprotein (LDL).

Conclusions

The findings of this study suggest that M. charantia could serve as a potential alternative for individuals with T2DM, particularly those with elevated total cholesterol levels. However, further high-quality studies are necessary to validate these results.

Polyphenolic profile and antioxidant properties of Momordica charantia L. 'Enaja' cultivar grown in Romania

This is the first study describing phenolics of Momordica charantia L. 'Enaja' cultivar (bitter melon) produced in Romania. Total polyphenol content, total tannin content, total flavonoid content, and antioxidant activity of bitter melon stems and leaves, young fruits, and ripe fruits grown in Romania were analysed, along with fruits imported from India. The UPLC-DAD analysis led to the identification of (+)-catechin, (-)-epicatechin, luteolin-3',7-di-O-glucoside, luteolin-7-O-glucoside and vanillic acid. (-)-Epicatechin (859 µg/g) and (+)-catechin (1677 µg/g) were the most abundant compounds in stems and leaves, while in the ripe fruits, luteolin-7-O-glucoside (310 µg/g) was the main phenolic. Stems and leaves were the most active for capturing free DPPH radicals (IC50 = 216.9 ± 11.91 µg/ml); the scavenging activity strongly correlated with the flavonoid content (r = 0.8806, r2 = 0.7754). Momordica charantia fruits from Romania, both young and ripe, are a source of polyphenols as valuable as those imported from India.

The metabolic effect of Momordica charantia cannot be determined based on the available clinical evidence: a systematic review and meta-analysis of randomized clinical trials

Several studies have shown that Momordica charantia L. (Cucurbitaceae, bitter melon) has beneficial effects on metabolic syndrome (MetS) parameters and exerts antidiabetic, anti-hyperlipidemic, and anti-obesity activities. Since the findings of these studies are contradictory, the goal of this systematic review and meta-analysis was to assess the efficacy of bitter melon in the treatment of metabolic syndrome, with special emphasis on the anti-diabetic effect. Embase, Cochrane, PubMed, and Web of Science databases were searched for randomized controlled human trials (RCTs). The meta-analysis was reported according to the PRISMA statement. The primary outcomes of the review are body weight, BMI, fasting blood glucose, glycated hemoglobin A1c, systolic blood pressure, diastolic blood pressure, serum triglyceride, HDL, LDL, and total cholesterol levels. Nine studies were included in the meta-analysis with 414 patients in total and 4-16 weeks of follow-up. In case of the meta-analysis of change scores, no significant effect could be observed for bitter melon treatment over placebo on fasting blood glucose level (MD = -0.03; 95% CI: -0.38 to 0.31; I2 = 34%), HbA1c level (MD = -0.12; 95% CI: -0.35 to 0.11; I2 = 56%), HDL (MD = -0.04; 95% CI: -0.17 to 0.09; I2 = 66%), LDL (MD = -0.10; 95% CI: -0.28 to 0.08; I2 = 37%), total cholesterol (MD = -0.04; 95% CI: -0.17 to 0.09; I2 = 66%,), body weight (MD = -1.00; 95% CI: -2.59-0.59; I2 = 97%), BMI (MD = -0.42; 95% CI: -0.99-0.14; I2 = 95%), systolic blood pressure (MD = 1.01; 95% CI: -1.07-3.09; I2 = 0%) and diastolic blood pressure levels (MD = 0.24; 95% CI: -1.04-1.53; I2 = 0%). Momordica treatment was not associated with a notable change in ALT, AST, and creatinine levels compared to the placebo, which supports the safety of this plant. However, the power was overall low and the meta-analyzed studies were also too short to reliably detect long-term metabolic effects. This highlights the need for additional research into this plant in carefully planned clinical trials of longer duration.

Effectiveness and Safety of Ayurvedic Medicines in Type 2 Diabetes Mellitus Management: A Systematic Review and Meta-Analysis

Introduction: Many Ayurvedic medicines have the potential for managing type 2 diabetes mellitus (T2DM), with previous systematic reviews demonstrating effectiveness and safety for specific Ayurvedic medicines. However, many of the reviews need updating and none provide a comprehensive summary of all the Ayurvedic medicines evaluated for managing T2DM. Objective: The objective of this systematic review was to evaluate and synthesize evidence on the effectiveness and safety of Ayurvedic medicines for managing T2DM. Inclusion criteria: Published and unpublished RCTs assessing the effectiveness and safety of Ayurvedic medicines for managing T2DM in adults. Methods: The JBI systematic review methodology was followed. A comprehensive search of sources (including 18 electronic databases) from inception to 16 January 2021 was made. No language restrictions were applied. Data synthesis was conducted using narrative synthesis and random effects meta-analyses, where appropriate. Pooled results are reported as mean differences (MD) with 95% confidence intervals (CI). Results: Out of 32,519 records identified from the searches, 219 articles were included in the systematic review representing 199 RCTs (21,191 participants) of 98 Ayurvedic medicines. Overall, in the studies reviewed the methodology was not adequately reported, resulting in poorer methodological quality scoring. Glycated hemoglobin (HbA1c) was reduced using Aegle marmelos (L.) Corrêa (MD -1.6%; 95% CI -3 to -0.3), Boswellia serrata Roxb. (-0.5; -0.7 to -0.4), Gynostemma pentaphyllum (Thunb.) Makino (-1; -1.5 to -0.6), Momordica charantia L. (-0.3; -0.4 to -0.1), Nigella sativa L. (-0.4; -0.6 to -0.1), Plantago ovata Forssk. (-0.9; -1.4 to -0.3), Tinospora cordifolia (Willd.) Hook.f. and Thomson (-0.5; -0.6 to -0.5), Trigonella foenum-graecum L. (-0.6; -0.9 to -0.4), and Urtica dioica L. (-1.3; -2.4 to -0.2) compared to control. Similarly, fasting blood glucose (FBG) was reduced by 4-56 mg/dl for a range of Ayurvedic medicines. Very few studies assessed health-related quality of life (HRQoL). Adverse events were not reported in many studies, and if reported, these were mostly none to mild and predominately related to the gastrointestinal tract. Conclusion: The current evidence suggests the benefit of a range of Ayurvedic medicines in improving glycemic control in T2DM patients. Given the limitations of the available evidence and to strengthen the evidence base, high-quality RCTs should be conducted and reported.

Three Selected Edible Crops of the Genus Momordica as Potential Sources of Phytochemicals: Biochemical, Nutritional, and Medicinal Values

Momordica species (Family Cucurbitaceae) are cultivated throughout the world for their edible fruits, leaves, shoots and seeds. Among the species of the genus Momordica, there are three selected species that are used as vegetable, and for medicinal purposes, Momordica charantia L (Bitter melon), Momordica foetida Schumach (Bitter cucumber) and Momordica balsamina L (African pumpkin). The fruits and leaves of these Momordica species are rich in primary and secondary metabolites such as proteins, fibers, minerals (calcium, iron, magnesium, zinc), β-carotene, foliate, ascorbic acid, among others. The extracts from Momordica species are used for the treatment of a variety of diseases and ailments in traditional medicine. Momordica species extracts are reputed to possess anti-diabetic, anti-microbial, anthelmintic bioactivity, abortifacient, anti-bacterial, anti-viral, and play chemo-preventive functions. In this review we summarize the biochemical, nutritional, and medicinal values of three Momordica species (M. charantia, M. foetida and M. balsamina) as promising and innovative sources of natural bioactive compounds for future pharmaceutical usage.

Antiglycation and Antioxidant Properties of Momordica charantia

The accumulation of advanced glycation endproducts (AGEs) and oxidative stress underlie the pathogenesis of diabetic complications. In many developing countries, diabetes treatment is unaffordable, and plants such as bitter gourd (or bitter melon; Momordica charantia) are used as traditional remedies because they exhibit hypoglycaemic properties. This study compared the antiglycation and antioxidant properties of aqueous extracts of M. charantia pulp (MCP), flesh (MCF) and charantin in vitro. Lysozyme was mixed with methylglyoxal and 0–15 mg/ml of M. charantia extracts in a pH 7.4 buffer and incubated at 37°C for 3 days. Crosslinked AGEs were assessed using gel electrophoresis, and the carboxymethyllysine (CML) content was analyzed by enzyme-linked immunosorbent assays. The antioxidant activities of the extracts were evaluated using assays to assess DPPH (1,1-diphenyl-2-picryl-hydrazyl) and hydroxyl radical scavenging activities, metal-chelating activity and reducing power of the extracts. The phenolic, flavonol and flavonoid content of the extracts were also determined. All extracts inhibited the formation of crosslinked AGEs and CML in a dose-dependent manner, with MCF being the most potent. The antioxidant activity of MCF was higher than that of MCP, but MCP showed the highest metal-chelating activity. MCF had the highest phenolic and flavonoid contents, whereas MCP had the highest flavonol content. M. charantia has hypoglycaemic effects, but this study shows that M. charantia extracts are also capable of preventing AGE formation in vitro. This activity may be due to the antioxidant properties, particularly the total phenolic content of the extracts. Thus, the use of M. charantia deserves more attention, as it may not only reduce hyperglycaemia but also protect against the build-up of tissue AGEs and reduce oxidative stress in patients with diabetes.

Beneficial role of bitter melon supplementation in obesity and related complications in metabolic syndrome

Diabetes, obesity, and metabolic syndrome are becoming epidemic both in developed and developing countries in recent years. Complementary and alternative medicines have been used since ancient era for the treatment of diabetes and cardiovascular diseases. Bitter melon is widely used as vegetables in daily food in Bangladesh and several other countries in Asia. The fruits extract of bitter melon showed strong antioxidant and hypoglycemic activities in experimental condition both in vivo and in vitro. Recent scientific evaluation of this plant extracts also showed potential therapeutic benefit in diabetes and obesity related metabolic dysfunction in experimental animals and clinical studies. These beneficial effects are mediated probably by inducing lipid and fat metabolizing gene expression and increasing the function of AMPK and PPARs, and so forth. This review will thus focus on the recent findings on beneficial effect of Momordica charantia extracts on metabolic syndrome and discuss its potential mechanism of actions.

Reasons why Thai patients with chronic kidney disease use or do not use herbal and dietary supplements

BACKGROUND

Despite a high prevalence of herbal and dietary supplement use (HDS) in pre-dialysis patients, the reasons are unknown as to why they decide to use HDS. Objectives of the cross-sectional and qualitative studies were to determine reasons for the use and non-use of HDS in Thai patients with chronic kidney disease (CKD).

METHODS

This prospective study recruited 421 patients with stage 3-5 CKD from two kidney clinics in Thailand, and 357 were followed up regarding their HDS use over 12 months. Patients receiving renal replacement therapy at baseline were excluded. Participants were interviewed at baseline and in the twelfth month regarding their HDS use, and reasons for their use or non-use of HDS. Among HDS users, 16 patients were enrolled in a qualitative study and were interviewed using eight-open ended questions about reasons for HDS use. Descriptive and thematic analyses were performed.

RESULTS

Thirty-four percent of patients with CKD consistently used HDS over the 12 months and 17% of all patients intermittently took them during the follow-up period. At baseline, family or friends' recommendation was the most common reason for HDS use (35%), followed by having a perception of benefits from using HDS (24%). During the follow-up period, perceived benefits of HDS was a frequently reported reason for either continuing with HDS use (85%) or starting to use HDS (65%). Negative experience from using HDS influenced patients to stop using them (19%). Although the main reason for non-use of HDS was trust in a doctor or effectiveness of conventional medicine (32%), doubt about the benefits from HDS or concerns about negative effects were frequently reported reasons for non-use (23%). Doctor's recommendations to avoid using HDS were the main influence for non-users (19%) and for those who had stopped using HDS (23%). The media and patients' social network had an impact on HDS use.

CONCLUSIONS

Patients who perceived benefits from HDS use were more likely to use HDS, whilst non-users had negative attitudes towards HDS. Health professionals therefore should educate patients and their relatives about the risks and benefits from using HDS.