Hypoglycemic and hypolipidemic effects of different parts and formulations of bitter gourd (Momordica Charantia)

Extraction methods, multiple biological activities, and related mechanisms of Momordica charantia polysaccharide: A review

Momordica Charantia Polysaccharide (MCP) is a key bioactive compound derived from bitter melon fruit. This review summarizes the advancements in MCP research, including extraction techniques, biological activities, and mechanisms. MCP can be extracted using various methods, and has demonstrated hypoglycemic, antioxidant, anti-inflammatory, and immunoregulatory effects. Research suggests that MCP may regulate metabolic enzymes, oxidative stress reactions, and inflammatory pathways. The review highlights the potential applications of MCP in areas such as anti-diabetes, antioxidant, anti-inflammatory, and immunoregulatory research. Future research should focus on elucidating the molecular mechanisms of MCP and optimizing extraction methods. This review provides a foundation for further research and utilization of MCP.

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.

Natural products for the treatment and management of diabetes mellitus in Zimbabwe-a review

Use of medicinal plants and herbs in the treatment and management of diseases, including diabetes mellitus and its complications remains an integral part of African tradition. In Zimbabwe, nearly one million people are living with diabetes mellitus. The prevalence of diabetes mellitus in Zimbabwe is increasing every year due to lifestyle changes, and has accelerated the use of traditional medicines for its treatment and management in urban areas. In addition, the high cost of modern medicine has led many people in rural parts of Zimbabwe to rely on herbal plant medicine for the treatment of diabetes mellitus and its complications. This review highlights a number of studies carried out to evaluate the antidiabetic properties of indigenous plants found in Zimbabwe with the goal of treating diabetes mellitus. Further, we discuss the mechanism of action of various plant extracts in the treatment and management of diabetes mellitus. Together, this review article can open pathways leading to discovery of new plant derived medicines and regularization of use of crude plant remedies to treat diabetes mellitus by the Zimbabwean government and others across Africa.

Traditional Medicine Use among Type 2 Diabetes Patients in KZN

Background. Traditional medicine (TM) is widely used in both developing and developed countries to assist in the attempt to curtail the prevalence and increase in diabetes mellitus. Approximately 53% of South Africans use TM to prevent and treat their diseases. There is no conclusive evidence regarding the safety and effectiveness of TM versus prescribed medicine. The most common therapies used by diabetics in Africa include herbal treatments, nutritional products, spiritual healing, and relaxation techniques. Therefore, this study aimed to evaluate the use of TM in patients with T2DM who are on chronic therapy and living in KwaZulu-Natal. Method. This cross-sectional study was conducted at a district hospital, in which purposive sampling was used to recruit participants and data were collected using a structured questionnaire. Information collected included demographic data, information pertaining to home remedies/TM, and self-care practices employed by participants while using TM. Data were analyzed using Pearson’s chi-squared test, t-test, and multivariate logistic regressions to determine predictors of TM usage. Results. Only 92 (27%) of 340 participants reported using TM, with Indians being the most frequent users (58.24%). Approximately, 83.72% (n = 72) used TM in conjunction with prescribed medication. Most participants (56.32%) acquired TM knowledge from family. The most frequently used TM was lemon and honey, Aloe vera, bitter gourd, green tea, and cinnamon. Traditional medicine use among African participants was 0.56 times (OR = 0.56, 95% CI = 0.34, 0.93) lower than Indian participants. There were no significant predictors for TM usage among the variables tested. Conclusion. A low prevalence rate of TM usage in T2DM patients was found. A significant correlation was noted between ethnicity and TM use. Large-scale studies are required to determine the additive and synergistic effects of TM in health care. Consideration should also be given to integrating TM into mainstream health care.

Complementary Strategy Enhancing Broad-Specificity for Multiplexed Immunoassay of Adulterant Sulfonylureas in Functional Food

Sulfonylureas, a family of anti-diabetic drugs widely used in the clinical treatment of type 2 diabetes, have recently emerged as an illegal adulterant in functional foods, to enhance the claimed anti-diabetic activity. To establish a screening assay method against their adulteration, with the aid of molecular simulation of hapten, two antibodies were raised and complementarily used to enhance the broad-specificity of an enzyme-linked immunosorbent assay (ELISA), which demonstrated simultaneous detection capability to 6 sulfonylureas; the detection limits ranged from 0.02 to 1.0 ng/mL, and recoveries were between 78.3% to 104.5%. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) confirmed the reliability of the proposed ELISA, based on real samples. These results suggest that the proposed ELISA could be an ideal method for screening to monitor for illicit adulteration of sulfonylureas in functional pill products.

Transcriptome and metabolome changes induced by bitter melon (Momordica charantia)- intake in a high-fat diet induced obesity model

Background and aim

Metabolic syndrome (MetS) is a complex disease of physiological imbalances interrelated to abnormal metabolic conditions, such as abdominal obesity, type II diabetes, dyslipidemia and hypertension. In the present pilot study, we investigated the nutraceutical bitter melon (Momordica charantia L) -intake induced transcriptome and metabolome changes and the converging metabolic signaling networks underpinning its inhibitory effects against MetS-associated risk factors.

Experimental procedure

Metabolic effects of lyophilized bitter melon juice (BMJ) extract (oral gavage 200 mg/kg/body weight-daily for 40 days) intake were evaluated in diet-induced obese C57BL/6J male mice [fed-high fat diet (HFD), 60 kcal% fat]. Changes in a) serum levels of biochemical parameters, b) gene expression in the hepatic transcriptome (microarray analysis using Affymetrix Mouse Exon 1.0 ST arrays), and c) metabolite abundance levels in lipid-phase plasma [liquid chromatography mass spectrometry (LC-MS)-based metabolomics] after BMJ intervention were assessed.

Results and conclusion

BMJ-mediated changes showed a positive trend towards enhanced glucose homeostasis, vitamin D metabolism and suppression of glycerophospholipid metabolism. In the liver, nuclear peroxisome proliferator-activated receptor (PPAR) and circadian rhythm signaling, as well as bile acid biosynthesis and glycogen metabolism targets were modulated by BMJ (p < 0.05). Thus, our in-depth transcriptomics and metabolomics analysis suggests that BMJ-intake lowers susceptibility to the onset of high-fat diet associated MetS risk factors partly through modulation of PPAR signaling and its downstream targets in circadian rhythm processes to prevent excessive lipogenesis, maintain glucose homeostasis and modify immune responses signaling.

Broad-specific immunochromatography for simultaneous detection of various sulfonylureas in adulterated multi-herbal tea

Sulfonylureas (SUs) are a series of anti-diabetic drugs widely used for type 2 diabetes mellitus for clinic treat. However, it is often illegally adulterated in multi-herbal tea to improve the claimed anti-diabetic activity in recent years. In this study, a novel hapten was rationally designed, and a broad-specific monoclonal antibody (anti-SUs mAb) recognizing nine SUs was developed. This mAb was used to develop a colloidal gold lateral flow immunochromatographic assay (CG-LFIA). The anti-SUs mAb demonstrated half inhibitory concentration (IC₅₀) ranged from 0.15 ng/mL to 3.25 ng/ mL for nine SUs by ELISA. The cut-off value of developed CG-LFIA for nine SUs was from 3 to 100 ng/ mL for the spiked samples. LC-MS/MS confirmed the reliability of the new CG-LFIA. The results indicated that the proposed CG-LFIA could be an ideal method in on-site screening surveillance assay for SUs illegally adulterated in multi-herbal tea products.

Double emulsion-based mayonnaise encapsulated with bitter gourd extract exhibits improvement in vivo anti-diabetic action in STZ induced rats

Bitter gourd contains charantin (steroidal saponins), insulin-like peptides, and alkaloids, which contribute to its hypoglycemic ability. The study aims to evaluate effects of anti-diabetic potential of bitter gourd (Momordica charantia) encapsulated double emulsion-based functional mayonnaise on the normal and streptozotocin-induced type 2 diabetes in albino male Wister rats. The rats were allocated into seven groups: a control group fed with synthetic diet (NC), two non-diabetic groups (NCM and NFM) and four diabetic-induced groups (DC, DCM, DFM, and DCMB) for 8 weeks and then analyzed for the various biochemical parameters. The results of this study revealed significant (p < 0.05) anti-diabetic potential in streptozotocin-induced diabetic male albino Wistar rats with decrease in blood glucose and HbA1c, increase in body weight, hemoglobin, and plasma insulin.

De novo assembly and Transcriptome Analysis of the Momordica charantia Seedlings Responding to methyl jasmonate using 454 pyrosequencing

Momordica charantia, a medicinal and edible species of the Cucurbitaceae family, has been widely used as a vegetable around the world. Hundreds of pharmacological compounds isolated from the M. charantia have been reported. However, the mechanism of action of the secondary metabolites has not been fully elucidated. In this study, 118,590 unigenes were gained by de novo assembly based on the raw data from high-throughput sequencing of mRNA (RNA-Sequencing) upon systemic analysis, among which, 51,860 (43.73%) could be annotated to the public sequence databases such as Nr, GO, Swiss-Prot, KEGG and KOG. The transcriptomic changes of M. charantia seedlings treated with or without methyl jasmonate (MeJA) were analyzed to identify key genes involved in MeJA treatment. Additionally, 554 differentially expressed genes (DEGs), including 328 up-regulated ones and 226 down-regulated genes, have been identified. Most DEGs were associated with secondary metabolism and stress responses. Meanwhile, six DEGs were further confirmed by quantitative real-time RT-PCR (qRT-PCR) analysis, resulting in similar expression patterns as compared to those of RNA-Sequencing. Nine significantly enriched pathways including 11 DEGs were identified to be possibly involved in the MeJA-responsive biosynthesis of secondary metabolites based on the transcriptome sequencing analysis. Among them, 4 DEGs, encoding two peroxidases, one cinnamyl alcohol dehydrogenase and one hypothetical protein Csa, might play important roles in the process of phenylpropanoid biosynthesis. In addition, 9 transcription factors (TFs) were also detected as DEGs from 1899 unigenes. Most of them up-regulated by MeJA treatment might be potentially involved in regulating secondary metabolites biosynthesis. This work is the first research on the large-scale assessment of M. charantia transcriptomic resources and the analysis of DEGs and TFs in secondary metabolites biosynthesis of M. charantia seedings treated with or without MeJA, which will be conducive to the further applications of M. charantia.

In Vitro and In Vivo Screening of Wild Bitter Melon Leaf for Anti-Inflammatory Activity against Cutibacterium acnes

Cutibacterium acnes (formerly Propionibacterium acnes) is a key pathogen involved in the development and progression of acne inflammation. The numerous bioactive properties of wild bitter melon (WBM) leaf extract and their medicinal applications have been recognized for many years. In this study, we examined the suppressive effect of a methanolic extract (ME) of WBM leaf and fractionated components thereof on live C. acnes-induced in vitro and in vivo inflammation. Following methanol extraction of WBM leaves, we confirmed anti-inflammatory properties of ME in C. acnes-treated human THP-1 monocyte and mouse ear edema models. Using a bioassay-monitored isolation approach and a combination of liquid–liquid extraction and column chromatography, the ME was then separated into n-hexane, ethyl acetate, n-butanol and water-soluble fractions. The hexane fraction exerted the most potent anti-inflammatory effect, suppressing C. acnes-induced interleukin-8 (IL-8) production by 36%. The ethanol-soluble fraction (ESF), which was separated from the n-hexane fraction, significantly inhibited C. acnes-induced activation of mitogen-activated protein kinase (MAPK)-mediated cellular IL-8 production. Similarly, the ESF protected against C. acnes-stimulated mouse ear swelling, as measured by ear thickness (20%) and biopsy weight (23%). Twenty-four compounds in the ESF were identified using gas chromatograph–mass spectrum (GC/MS) analysis. Using co-cultures of C. acnes and THP-1 cells, β-ionone, a compound of the ESF, reduced the production of IL-1β and IL-8 up to 40% and 18%, respectively. β-ionone also reduced epidermal microabscess, neutrophilic infiltration and IL-1β expression in mouse ear. We also found evidence of the presence of anti-inflammatory substances in an unfractionated phenolic extract of WBM leaf, and demonstrated that the ESF is a potential anti-inflammatory agent for modulating in vitro and in vivo C. acnes-induced inflammatory responses.

The gut microbiota confers the lipid-lowering effect of bitter melon (Momordica charantia L.) In high-fat diet (HFD)-Induced hyperlipidemic mice

The bitter melon (Momordica charantia) is a medical food with well-documented hypoglycemic and anti-hyperlipidemic activities. Previous studies showed that the M. charantia fruit (MC) could modulate the gut microbiota, but whether this modulation is essential for MC's pharmacological effects is largely unknown. Here, we assessed the causality of gut microbes in MC-elicited anti-hyperlipidemic effects for the first time. Oral administration of MC significantly prevented hyperlipidemia, but this amelioration substantially diminished when co-treated with antibiotics. Transplantation of gut flora from MC-treated donor mice also significantly decreased serum lipids. The microbiological analysis revealed that MC moderately increased diversity and shifted the overall structure of gut microbiota. It selectively enhanced the relative abundance of short-chain fatty acid (SCFAs)-producing genera and increased fecal SCFAs content. These results demonstrate that M. charantia fruit (MC) may exert an anti-hyperlipidemic effect through modulating gut microbes and increasing SCFAs production.

Selection and validation of appropriate reference genes for real-time quantitative PCR analysis in Momordica charantia

Real time quantitative reverse transcription PCR (RT-qPCR) has been attracting more attention for its high sensitivity in gene expression analysis. Given the widely use of RT-qPCR in normalization, it is playing a pivotal role for seeking suitable reference genes in different species. In current work, 12 candidate reference genes including Actin 2 (ACT2), Cyclophilin 2 (CYP2), Glyceraldehyde-3-phosphate dehydrogenase C2 (GAPC2), Elongation factor 1-α (EF1-α), Nuclear cap binding protein 20 (NCBP20), Serine/threonine-protein phosphatase PP2A (PP2A), Polypyrimidine tract-binding protein 1 (PTBP1), SAND family protein (SNAD), TIP41-like protein (TIP41), Tubulin beta-6 (TUB6), Ubiquitin-conjugating enzyme 9 (UBC9) and Glyceraldehyde-3-phosphatedehydrogenase (GAPDH) were screened from the transcriptome datasets of M. charantia. Afterwards, GeNorm, NormFinder and BestKeeper algorithms were applied to assess the expression stability of these 12 genes under different abiotic stresses including drought, cold, high-salt, hormone, UV, oxidative and metal stress. The results indicated that 12 selected genes exhibited various stability across the samples under different external stress conditions, but TIP41, PTBP1 and PP2A presented high stability among all the reference genes. To validate the suitability of the identified reference genes, the results of hormone subset were compared with RNA sequencing (RNA-seq) data, and the relative abundance of Ascorbate peroxidase 1（APX1）was used to confirm the reliability of the results. This work assesses the stability of reference genes in M. charantia under different abiotic stress conditions, which will be beneficent for accurate normalization of target genes in M. charantia.

Possible molecular mechanisms of glucose-lowering activities of Momordica charantia (karela) in diabetes

Diabetes mellitus is a highly prevalent metabolic disorder which is characterized by impaired glucose tolerance, with a relative or absolute insulin deficiency and profound changes in the metabolism of macronutrients. Traditional and complementary medicine is therapeutic strategies that have both been applied to improving glycemic control. Momordica charantia is one of the plant-based, folk medicines that used for improving glycemic control. We aimed to review, the effects of M. charantia on blood glucose with a clarification of the molecular pathways involved. Of the compounds derived from the plants, the insulin-like peptide, charantin, and the alkaloid vicine, have been reported to have hypoglycemic effects. Different mechanisms contribute to the antidiabetic activities of M. charantia, these include increasing pancreatic insulin secretion, decreasing insulin resistance and increasing peripheral and skeletal muscle cell glucose utilization, inhibition of intestinal glucose absorption and suppressing of key enzymes in the gluconeogenic pathways.

Postprandial Glucose Levels Are Better Associated with the Risk Factors for Diabetes Compared to Fasting Glucose and Glycosylated Hemoglobin (HbA1c) Levels in Elderly Prediabetics: Beneficial Effects of Polyherbal Supplements-A Randomized, Double-Blind, Placebo Controlled Trial

Backgrounds

Prediabetes is a condition in which a person's blood glucose levels are higher than normal physiological levels but lower compared to patients with diabetes. Up to 70% of individuals with prediabetes will eventually develop diabetes. To date, there have been no pharmaceutical drugs to treat diabetes. It is believed that early diagnosis and nonpharmacological intervention for prediabetes are critical for effective prevention of diabetes. Most individuals with prediabetes remain undiagnosed even after being evaluated using the standard tests for fasting glucose (FG) and HbA1c. We investigated if postprandial glucose levels (2h-PG) were associated with pre/diabetes and if polyherbal supplements could be beneficial for individuals with prediabetes.

Materials and Methods

100 elderly individuals with impaired 2h-PG or fasting glucose levels were recruited to receive either a 12-week supplement of GlucoVita (an antioxidative polyherbal formulation) (n=50) or placebo (n=50).

Results

No baseline differences were observed for FG, HbA1c, or 2h-PG. Individuals who received a twelve-week administration of GlucoVita supplements had significantly reduced 2h-PG (8.15±1.67 versus 7.35±2.06 mmol/l, P<0.05) levels compared to individuals in the placebo group. In addition, HbA1c levels were lower in individuals who received GlucoVita (5.81±0.49 %) compared to the individuals in the placebo group (6.00±0.51%) (P=0.08) after 12-weeks. Stratified analysis, based on impaired fasting glucose (IFG), 2h-PG, metabolic symptom, and age, demonstrated that, after the 12-week intervention, HbA1c levels were significantly lower in the GlucoVita administered group compared to the placebo group (IFG subgroup; 5.85±0.46%, n= 27 versus 6.14±0.50, n=33, P<0.05) and the metabolic symptom-free subgroup (5.73±0.45%, n=23 versus 6.04±0.52%, n=24, P<0.05). GlucoVita also reduced FG in individuals with normal 2h-PG (6.37±0.27 versus 6.08±0.38 mmol/l, P<0.05). Baseline 2h-PG levels, but not HbA1c or FG levels, were significantly correlated with body weight, waist circumference, and BMI (r=0.25, P<0.05; r=0.31, P<0.01; r=0.22, P<0.05, respectively).

Conclusion

2h-PG levels were better associated with body weight, waist circumference, and BMI risk factors compared to FG and HbA1c levels in elderly individuals with prediabetes. Polyherbal formulation GlucoVita supplements improved 2h-PG and HbA1c levels only in elderly individuals who were overweight but were symptom-free and under 65 years of age. Due to the small cohort size of this pilot study, future studies are required to validate our findings.

Potential adverse effects of botanical supplementation in high-fat-fed female mice

BACKGROUND

Insulin resistance underlies metabolic syndrome and is associated with excess adiposity and visceral fat accumulation, which is more frequently observed in males than females. However, in young females, the prevalence of metabolic syndrome is rising, mainly driven by accumulation of abdominal visceral fat. The degree to which sex-related differences could influence the development of insulin resistance remains unclear, and studies of potential therapeutic strategies to combat metabolic syndrome using rodent models have focused predominantly on males. We therefore evaluated the effects of two nutritional supplements derived from botanical sources, an extract of Artemisia dracunculus L. (termed PMI5011) and Momordica charantia (commonly known as bitter melon), on female mice challenged with a high-fat diet in order to determine if dietary intake of these supplements could ameliorate obesity-induced insulin resistance and metabolic inflexibility in skeletal muscle.

METHODS

Body composition, physical activity and energy expenditure, fatty acid oxidation, insulin signaling, and gene and protein expression of factors controlling lipid metabolism and ectopic lipid accumulation were evaluated in female mice fed a high-fat diet supplemented with either PMI5011 or bitter melon. Statistical significance was assessed by unpaired two-tailed t test and repeated measures ANOVA.

RESULTS

PMI5011 supplementation resulted in increased body weight and adiposity, while bitter melon did not induce changes in these parameters. Pyruvate tolerance testing indicated that both supplements increased hepatic glucose production. Both supplements induced a significant suppression in fatty acid oxidation in skeletal muscle homogenates treated with pyruvate, indicating enhanced metabolic flexibility. PMI5011 reduced lipid accumulation in skeletal muscle, while bitter melon induced a downward trend in lipid accumulation in the skeletal muscle and liver. This was accompanied by transcriptional regulation of autophagic genes by bitter melon in the liver.

CONCLUSIONS

Data from the current study indicates that dietary supplementation with PMI5011 and bitter melon evokes a divergent, and generally less favorable, set of metabolic responses in female mice compared to effects previously observed in males. Our findings underscore the importance of considering sex-related variations in responses to dietary supplementation aimed at combating metabolic syndrome.