Bitter melon triterpenes work as insulin sensitizers and insulin substitutes in insulin-resistant cells

In Vitro Studies of Pumpkin (Cucurbita moschata var. Kashi Harit) Seed Protein Fraction(s) to Evaluate Anticancer and Antidiabetic Properties

Chronic diseases like cancer and diabetes are the major public health concerns of India and worldwide. Nowadays, plant-derived products are in great demand for the treatment of these diseases. Pumpkin seeds are traditionally implicated for their pharmacological properties, as exemplified by benign prostatic hyperplasia. Earlier, pumpkin seed proteins were extracted by the Osborne method, and their functional and nutritional qualities were evaluated. Here, the aim is to assess in vitro, the anticancer and antidiabetic properties of seed protein fractions. HepG2, MDA-MB-231, and MCF-7 cell lines were treated with water-soluble (WF) and alkali-soluble fractions (AF) to assess cytotoxicity, while pancreatic β-cells and insulin resistance (IR) - HepG2 cell lines were treated with WF to evaluate the antidiabetic potential. WF and AF showed cytotoxic effects towards HepG2 and MDA-MB-231 cell lines, suggesting apoptosis-mediated anticancerous activity. WF potentiates glucose-stimulated insulin secretion in pancreatic β-cells, in a dose-dependent manner. In IR-HepG2 cell line studies, control, metformin, and WF-treated groups showed uptake of glucose, when compared to the diabetic group, which is well-correlated with the upregulated expressions of GLUT2 and GLUT4 transporters in these groups. These results indicate that proteins from WF and AF may have anticancerous and antidiabetic properties and thus have the potential to utilize pumpkin proteins in the management of cancer and diabetes.

Cardioprotective and hypotensive mechanistic insights of hydroethanolic extract of Cucumis melo L. kernels in isoprenaline-induced cardiotoxicity based on metabolomics and in silico electrophysiological models

Background: Cardiovascular diseases (CVD) continue to threaten health worldwide, and account for a significant portion of deaths and illnesses. In both developing and industrialized nations, they challenge their health systems. There are several traditional uses of Cucurbitaceae seeds in Pakistan, India, Iran, and China, including treating cardiovascular, neurological, and urogenital diseases. Methods: In the present work, integrated techniques of metabolomics profiling and computational cardiomyocyte stimulation were used to investigate possible mechanisms of C. melo in isoprenaline (ISO)-induced myocardial infarction. In vitro, vasoconstrictions, paired atria, and in vivo invasive blood pressure measurement models were performed to explore the mechanism of action of C. melo hydroethanolic seed extract (Cm-EtOH). Results: Results showed that Cm-EtOH demonstrates NO-based endothelium-derived relaxing factor (EDRF) vasorelaxant response, negative chronotropic and inotropic response in the atrium, and hypotensive effects in normotensive rats. Results also revealed that Cm-EtOH decreases cardiomyocyte hypertrophy and reverts the altered gene expressions, biochemical, and metabolites in ISO-induced myocardial infarction (MI) rats. The extract additionally reversed ISO-induced MI-induced oxidative stress, energy consumption, and amino acid metabolism. Moreover, C. melo seeds increased EDRF function, energy production, and antioxidant capacity to treat myocardial and vascular disorders. In computational cardiomyocyte simulation, gallic acid reduced action potential duration, upstroke velocity (dV/dtmax), and effective refractory period. Conclusion: This study highlights the therapeutic potential of C. melo seeds to treat cardiovascular diseases and provides mechanistic insight into its antihypertensive and cardioprotective activities.

Mexican Plants Involved in Glucose Homeostasis and Body Weight Control: Systematic Review

BACKGROUND

Obesity is defined as abnormal or excessive fat accumulation, provoking many different diseases, such as obesity and type 2 diabetes. Type 2 diabetes is a chronic-degenerative disease characterized by increased blood glucose levels. Obesity and type 2 diabetes are currently considered public health problems, and their prevalence has increased over the last few years. Because of the high cost involved in the treatment of both diseases, different alternatives have been sought. However, the general population uses medicinal plants, in the form of tea or infusions, to treat different diseases. Therefore, traditional medicine using medicinal plants has been investigated as a possible treatment for type 2 diabetes and body weight control.

AIM OF THE STUDY

The purpose of this review is to find medicinal plants used in Mexico that could exert their beneficial effect by regulating insulin secretion and body weight control.

MATERIAL AND METHOD

For the development of this review, Mexican plants used in traditional medicine to treat type 2 diabetes and body weight control were searched in PubMed, Google Scholar, and Scopus. The inclusion criteria include plants that presented a significant reduction in blood glucose levels and/or an increase in insulin secretion.

RESULTS

We found 306 Mexican plants with hypoglycemic effects. However, plants that did not show evidence of an increase in insulin secretion were eliminated. Finally, only five plants were included in this review: Momordica charantia L. (melón amargo), Cucurbita ficifolia bouché (chilacayote), Coriandrum sativum L. (cilantro), Persea americana Mill. (aguacate) Bidens pilosa (amor seco), including 39 articles in total. Here, we summarized the plant extracts (aqueous and organic) that have previously been reported to present hypoglycemic effects, body weight control, increased secretion and sensitivity of insulin, improvement of pancreatic β cells, and glucose tolerance. Additionally, these effects may be due to different bioactive compounds present in the plants' extracts.

CONCLUSION

Both in vivo and in vitro studies are required to understand the mechanism of action of these plant extracts regarding insulin secretion to be used as a possible treatment for type 2 diabetes and body weight control in the future.

Effect of superfine grinding on physical properties, bioaccessibility, and anti-obesity activities of bitter melon powders

BACKGROUND

Bitter melon is widely applied to the treatment of diabetes and obesity, but few studies focus on the processing procedure of bitter melon. The differences in physical properties, bioaccessibility, and anti-obesity activity of bitter melon powder (BMP) produced with or without superfine grinding were investigated to optimize an effective processing procedure.

RESULTS

Results showed that superfine grinding could improve the physical properties of BMP, represented by greater bulk density, lower water-holding capacity, and higher bioactive compounds' solubilities. Superfine grinding remarkably affected the bioaccessibility of phenolics and the antioxidant capacity of bitter melon during in vitro digestion. Meanwhile, after a 4 week treatment, 25 μm BMP showed a greater anti-obesity activity with reduction in the serum insulin levels from 16.47 to 13.10 mIU L^-1 , reversing high-fat-diet-induced glucose intolerance, decreasing levels of serum lipids and hepatic lipid accumulation compared with the high-fat diet group.

CONCLUSION

In conclusion, superfine grinding was beneficial for improving the physical properties and bioaccessibility, simultaneously facilitating the anti-obesity activity of bitter melon, which will provide a reference for direct utilization of bitter melon as a health food to relieve symptoms of obesity. © 2022 Society of Chemical Industry.

Cytotoxic and Anti-Inflammatory Triterpenoids in the Vines and Leaves of Momordica charantia

The vines and leaves of Momordica charantia L. are used as herbal medicines to treat inflammation-related disorders. However, their safety profile remains uncharacterized, and the constituents in their extracts that exert anti-inflammatory and adverse effects remain unclear. This study isolated the characteristic cucurbitane-type triterpenoid species in the vines and leaves of M. charantia L. and analyzed their cytotoxicity, anti-inflammatory effects, and underlying mechanisms. Four structurally related triterpenoids—momordicines I, II, IV, and (23E) 3β,7β,25-trihydroxycucurbita-5,23-dien-19-al (TCD)—were isolated from the triterpenoid-rich fractions of extracts from the vines and leaves of M. charantia. Momordicine I was cytotoxic on normal cells, momordicine II exerted milder cytotoxicity, and momordicine IV and TCD had no obvious adverse effects on cell growth. TCD had anti-inflammatory activity both in vivo and in vitro. In lipopolysaccharide-stimulated RAW 264.7 cells, TCD inhibited the inhibitor kappa B kinase/nuclear factor-κB pathway and enhanced the expression of nuclear factor erythroid 2-related factor 2, heme oxygenase-1, and glutamate-cysteine ligase modifier subunit through the extracellular signal-regulated kinase1/2 and p38. Thus, the vines and leaves of M. charantia should be used with caution. An extraction protocol that can enrich TCD but remove momordicine I would likely enhance the safety of the extract.

Molecular docking of phytochemical compounds of Momordica charantia as potential inhibitor against SARS-CoV-2

BACKGROUND

Coronavirus disease 2019 (COVID-19) has been recently declared as a global public health emergency, where the infection is caused by SARS-CoV-2. Nowadays, there is no specific treatment to cure this infection. SARS-CoV-2 main protease (Mpro) and SARS spike glycoprotein-human ACE2 complex have been recognized as suitable targets for treatment including COVID-19 vaccines.

OBJECTIVE

In our current study, we identified the potential of Momordica charantia as a prospective alternative and a choice in dietary food during pandemic.

MATERIALS AND METHODS

A total of 16 bioactive compounds of Momordica charantia were screened for activity against 6LU7 and 6CS2 with AutoDock Vina.

RESULTS

We found that momordicoside B showed lowest binding energy compared with other compounds. In addition, kuguaglycoside A and cucurbitadienol provide better profiles for drug-like properties based on Lipinski's rule of five.

CONCLUSION

Our result indicates that these molecules may be further explored as promising candidates against SARS-CoV-2 or just simply suggested that Momordica charantia as one of the best food alternatives to be consumed during pandemic.

Flavonoids, alkaloids and terpenoids: a new hope for the treatment of diabetes mellitus

Diabetes mellitus is a metabolic syndrome characterized by a hyperglycemic state and multi-organ failure. Millions of people worldwide are suffering from this deadly disease taking a hit on their pocket and mental health in the name of its treatment. Modern medical practices with new technological advancements and discoveries have made revolutionary changes in the treatment. But, unfortunately, Glucose-lowering drugs used have many accompanying effects such as chronic vascular disease, renal malfunction, liver disease and, many skin problems. These complications have made us think about alternative treatments for diabetes with minimum or no side effects. Nowadays, in addition to modern medicine, herbal treatment has been suggested to treat diabetes mellitus. These herbal medicines contain biological macromolecules such as flavonoids, Terpenoids, glycosides, and alkaloids, which show versatile anti-diabetic effects. These phytochemicals are generally considered safe, and naturally occurring compounds have a potential role in preventing or controlling diabetes mellitus. The underlying mechanism of their anti-diabetic effects includes improvement in insulin secretion, decrease in insulin resistance, enhanced liver glycogen synthesis, antioxidant and anti-inflammatory activities. In this review, we have focused on the mechanism of various phytochemicals targeting hyperglycemia and its underlying pathogenesis.

Nutritional Composition and Health Benefits of Various Botanical Types of Melon (Cucumis melo L.)

Characterizing the diverse melon cultivars for nutrition aids in crop improvement and promoting a healthy diet. Here, we used in vitro assays to characterize the nutritional qualities and health-beneficial effects of 30 melon (Cucumis melo L.) genotypes, including 10 improved cultivars, 16 landraces, and 4 wild types collected from different parts of India. Two landraces (Sidoota and Alper Green) had the highest (12.20 and 11.25) total soluble solids (TSS) contents. The Sidoota and Pappusa landraces had high reducing sugar contents (2.84 and 2.81 mg g⁻¹ fresh weight [FW]). The highest polyphenols contents (22.0 mg g⁻¹ FW) were observed in the landraces Mage Kaayi-2, Budamekaayi, and Small Melon. Reflecting on the primary and secondary metabolite contents, the Mekke Kaayi and Giriyala landraces exhibited high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (97.6 and 91% at 100 μg mL⁻¹). Additionally, seven of the landraces showed significant nitric oxide (NO) induction activity (>80% inhibition at 200 μg mL⁻¹), indicating their potential health benefits, and seven showed considerable angiotensin-converting enzyme (ACE) inhibition activity (highest in Kashi Madhu), indicating their potential usefulness in reducing hypertension. Genotypes with high health beneficial compounds identified in this study can be used for breeding improved melon cultivars to promote these fruits as well as a healthy diet.

Bacillus amyloliquefaciens exopolysaccharide preparation induces glucagon-like peptide 1 secretion through the activation of bitter taste receptors

The exopolysaccharide preparation of Bacillus amyloliquefaciens amy-1 (EPS) regulates glycemic levels and promotes glucagon-like peptide 1 (GLP-1) secretion in vivo and in vitro. This study aimed to identify the molecular mechanism underlying EPS-induced GLP-1 secretion. HEK293T cells stably expressing human Gα-gustducin were used as a heterologous system for expressing the genes of human bitter taste receptor (T2R) 10, 14, 30, 38 (PAV), 38 (AVI), 43, and 46, which were expressed as recombinant proteins with an N-terminal tag composed of a Lucy peptide and a human somatostatin receptor subtype 3 fragment for membrane targeting and a C-terminal red fluorescent protein for expression monitoring. EPS induced a dose-dependent calcium response from the human NCI-H716 enteroendocrine cell line revealed by fluorescent calcium imaging, but inhibitors of the G protein-coupled receptor pathway suppressed the response. EPS activated heterologously expressed T2R14 and T2R38 (PAV). shRNAs of T2R14 effectively inhibited EPS-induced calcium response and GLP-1 secretion in NCI-H716 cells, suggesting the involvement of T2R14 in these effects. The involvement of T2R38 was not characterized because NCI-H716 cells express T2R38 (AVI). In conclusion, the activation of T2Rs mediates EPS-induced GLP-1 secretion from enteroendocrine cells, and T2R14 is a critical target activated by EPS in these cells.

Xiaokeyinshui extract combination, a berberine-containing agent, exerts anti-diabetic and renal protective effects on rats in multi-target mechanisms

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaokeyinshui (XKYS) formula, an anti-diabetic formula, was recorded in many ancient Chinese medical books. Xiaokeyinshui extract combination (XEC) originated from this ancient formula, consisting extracts of four herbal drugs, namely, Coptidis Rhizoma, Liriopes Radix, bitter melon, and Cassiae Semen.

OBJECTIVE

Therapeutic effects of Xiaokeyinshui extract combination (XEC) were assessed on diabetic rats.

MATERIALS AND METHODS

Herb extracts were prepared and mixed, yielding XEC. XEC were intragastrically given at doses of 260, 380 and 500 mg/kg/d to diabetic rats for 60 days. Anti-diabetic effects of XEC were studied, with measurement of body weight, and assessment of both glycemic control and lipid management. Measurement of oxidative stress and inflammatory cytokines were conducted in accordance to protocols of commercial kits. Parameters related to renal functions were also measured. Western blot (WB) analysis was performed to explore the anti-diabetic and renal protective mechanisms of XEC.

RESULTS

Compared to diabetic control, XEC exhibited significant effects in both glucose-lowering and lipid management (p < 0.01). Both oxidative stress and inflammatory cytokines were reduced after treatment of XEC for two months. In addition, XEC exhibited renal protective effects. WB analysis of liver tissue demonstrated that XEC achieved anti-diabetic effects through up-regulation of InsRα/IRS-1/PI3K/Akt/GLUT4 signaling pathway and phosphorylation of AMPK. In addition, renal protective effects were also achieved with down-regulation of RAGE and VEGF expressions in kidney.

CONCLUSIONS

XEC exerts promising anti-diabetic and renal protective effects on diabetic rats in multi-target mechanisms. XEC could be a satisfying alternative treating T2DM and preventing diabetic nephropathy.

The Effect of Thermal Processing on the Saponin Profiles of Momordica charantia L

Saponins from Momordica charantia L. are a class of triterpenoid glucoside molecules that contribute to the bitter flavour of the plant and possess pharmacological properties. However, little is known about how the bioactivity and bitter flavour of saponins are affected by thermal processing. We established saponin profiles in bitter gourd extracts using a UPLC-ESI-MS/MS method. Seven saponins including momordicoside F1, momordicoside F2, momordicoside I, momordicoside K, momordicoside L, 3β,7β,25-trihydroxycucurbita-5, 23(E)-dien-19-al, and momordicine I were monitored for the effects of thermal processing on their stabilities. The results showed that both 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al and momordicoside L were extremely sensitive to heat treatment, particularly when they were heated at 100°C for more than 10 mins and under 121°C for 20 mins. Other saponins were reduced significantly by autoclaving, but they remained unchanged at lower temperatures. In conclusion, specific bitter gourd saponins are affected by thermal treatment, which may modify the bioactive components or bitter flavour of the bitter gourd extracts.

Probiotics Fermented Bitter Melon Juice as Promising Complementary Agent for Diabetes Type 2: Study on Animal Model

Background and Aim. Bitter melon (Momordica charantia/MC) contains charantin that has antidiabetic properties as an α-glucosidase inhibitor and antioxidative properties. Lactic acid fermentation using Lactobacillus fermentum LLB3 increased its antioxidative properties. The study was aimed to analyse the difference of the treatment that influences blood glucose and SOD level before and after treatment compared to acarbose. Experimental procedure. A total of 24 male Sprague-Dawley rats were used. Diabetes type 2 was induced by a single dose (60 mg/kg) of streptozotocin (STZ) and 120 mg/kg of nicotinamide, intraperitoneally. Following three days of STZ induction, the animals were randomly divided into four groups. Groups 1, 2, 3, and 4 were given acarbose 40 mg/100 g feed, MC 10 ml/kg body weight, fermented MC 10 ml/kg body weight, and distilled water, respectively, for 28 days. Glucose and SOD values were measured by spectrophotometer and ELISA, respectively. The difference between pretest and posttest data was analysed using the pair t-test. Data were analysed using ANOVA and Tukey HSD for post hoc analysis. Level of significance was set at 0.05.

Plant-Derived Oleanolic Acid (OA) Ameliorates Risk Factors of Cardiovascular Diseases in a Diet-Induced Pre-Diabetic Rat Model: Effects on Selected Cardiovascular Risk Factors

The pathogenesis of prediabetes is associated with risk factors such as chronic consumption of an unhealthy diet. Recent studies have reported that diet-induced pre-diabetes is also associated with risk factors of cardiovascular complications, hence this study was aimed at evaluating the effects of oleanolic acid (OA) on pre-diabetes rats. Pre-diabetes was induced by chronic exposure of Sprague Dawley rats (SD) to high-fat high-carbohydrate diet (20 weeks), whereas the non-pre-diabetes control (NC) was given standard rat chow. Pre-diabetes animals were grouped into five groups namely prediabetes control (PC), metformin treated (Met), metformin with diet intervention (Met + DI), oleanolic acid treated (OA), and oleanolic acid with diet intervention (OA + DI) then treated for 12 weeks. At the end of treatment, all animals were sacrificed where organs and tissues were harvested for biochemical analysis and histological studies. The results showed that PC had a significantly higher triglycerides (TGs), low density lipoprotein cholesterol (LDL-C, interleukin-6(IL-6), tumor necrosis factor alpha (TNFα), C-reactive protein (CRP), mean arterial pressure (MAP) and hearts weights in comparison to NC (p < 0.05). However, the administration of OA, in both the presence and absence of dietary intervention showed a significant decrease in TGs, LDL-C, IL-6, TNFα, CRP, MAP, hearts weights (p < 0.05). In conclusion, the administration of OA was able to lower the risks of developing CVDs in pre-diabetes rat model through ameliorating dyslipidaemia, oxidative stress, hypertension, and low-grade inflammation. Therefore OA has the potential to be used as an alternative treatment to prevent the onset of CVDs during pre-diabetes stage even in the absence of dietary and lifestyle intervention.

Cucurbitane triterpenoids from the fruit of Momordica charantia L. and their anti-hepatic fibrosis and anti-hepatoma activities

Momordica charantia L. (Cucurbitaceae) is a popular vegetable and traditional folk medicine, that has been used for hundreds of years. In this study, three undescribed cucurbitane-type triterpene glycosides furpyronecucurbitane A, goyaglycoside I and charantagenin F along with nine known compounds were isolated from the immature fruit of Momordica charantia L. Their structures were identified on the basis of extensive 1D, 2D NMR and HRESIMS spectroscopy analysis. All isolated compounds were examined for their anti-hepatic fibrosis activity against murine hepatic stellate cells (t-HSC/Cl-6) and anti-hepatoma activity against two kinds of liver cancer cell lines (HepG2 and Hep3B). Among them, karaviloside III exhibited excellent inhibitory activity against activated t-HSC/Cl-6 cells and cytotoxic activity against Hep3B and HepG2 cell lines with IC₅₀ values of 3.74 ± 0.13, 16.68 ± 2.07 and 4.12 ± 0.36 μM, respectively, which may potential to be developed as a chemotherapy agent for treatment hepatic fibrosis or carcinoma and protection against both diseases.

Comparison of Anti-Inflammatory Activities of Structurally Similar Triterpenoids Isolated from Bitter Melon

Momordica charantia L., or bitter melon, has been suggested to exhibit anti-inflammatory activity. In a previous study, three structurally similar triterpenes, namely 5β,19-epoxy-25-methoxycucurbita-6,23-diene-3β,19-diol (EMCD), 5β,19-epoxy-25-methoxycucurbita-6,23-dien-3β-ol (EMCO), and 5β,19-epoxy-19,25-dimethoxycucurbita-6,23-dien-3β-ol (EDMO), were isolated from bitter melon. EMCD has been shown to exhibit in vitro anti-inflammatory activity. In this study, the anti-inflammatory activities of EMCD, EMCO, and EDMO were compared. All three compounds were toxic to the RAW 264.7 macrophage cell line but not the FL83B cells. EMCD and EMCO inhibited tumor necrosis factor (TNF)-α-induced inducible nitric oxide synthase (iNOS) expression in FL83B cells, and the IC50 values were 19.8 and 25.7 μM, respectively. By contrast, EDMO did not effectively reduce iNOS expression. Furthermore, EMCD and EMCO suppressed other TNF-α-induced proinflammatory signals including the activation of inhibitor kappa B kinase complex, the phosphorylation of inhibitor of nuclear factor-κB, and the activation of c-Jun kinase. EMCD consistently exhibited a higher efficacy than did EMCO in these assays. Hence, the in vivo anti-inflammatory activity of EMCD was tested. EMCD clearly repressed 12- O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. In conclusion, differences in the functional group on carbon 19 do affect the anti-inflammatory activities of EMCD, EMCO, and EDMO. EMCD exhibited the highest anti-inflammatory activity among these molecules, and its in vivo anti-inflammatory activity was confirmed.

Recent Advances in Momordica charantia: Functional Components and Biological Activities

Momordica charantia L. (M. charantia), a member of the Cucurbitaceae family, is widely distributed in tropical and subtropical regions of the world. It has been used in folk medicine for the treatment of diabetes mellitus, and its fruit has been used as a vegetable for thousands of years. Phytochemicals including proteins, polysaccharides, flavonoids, triterpenes, saponins, ascorbic acid and steroids have been found in this plant. Various biological activities of M. charantia have been reported, such as antihyperglycemic, antibacterial, antiviral, antitumor, immunomodulation, antioxidant, antidiabetic, anthelmintic, antimutagenic, antiulcer, antilipolytic, antifertility, hepatoprotective, anticancer and anti-inflammatory activities. However, both in vitro and in vivo studies have also demonstrated that M. charantia may also exert toxic or adverse effects under different conditions. This review addresses the chemical constituents of M. charantia and discusses their pharmacological activities as well as their adverse effects, aimed at providing a comprehensive overview of the phytochemistry and biological activities of M. charantia.

Draft genome sequence of bitter gourd (Momordica charantia), a vegetable and medicinal plant in tropical and subtropical regions

Bitter gourd (Momordica charantia) is an important vegetable and medicinal plant in tropical and subtropical regions globally. In this study, the draft genome sequence of a monoecious bitter gourd inbred line, OHB3-1, was analyzed. Through Illumina sequencing and de novo assembly, scaffolds of 285.5 Mb in length were generated, corresponding to ∼84% of the estimated genome size of bitter gourd (339 Mb). In this draft genome sequence, 45,859 protein-coding gene loci were identified, and transposable elements accounted for 15.3% of the whole genome. According to synteny mapping and phylogenetic analysis of conserved genes, bitter gourd was more related to watermelon (Citrullus lanatus) than to cucumber (Cucumis sativus) or melon (C. melo). Using RAD-seq analysis, 1507 marker loci were genotyped in an F₂ progeny of two bitter gourd lines, resulting in an improved linkage map, comprising 11 linkage groups. By anchoring RAD tag markers, 255 scaffolds were assigned to the linkage map. Comparative analysis of genome sequences and predicted genes determined that putative trypsin-inhibitor and ribosome-inactivating genes were distinctive in the bitter gourd genome. These genes could characterize the bitter gourd as a medicinal plant.

Separation of cucurbitane triterpenoids from bitter melon drinks and determination of partition coefficients using vortex-assisted dispersive liquid-phase microextraction followed by UHPLC analysis

A rapid, effective method applying vortex-assisted liquid-liquid microextraction before ultra-high performance liquid chromatography with mass spectrometry and evaporative light scattering detection was developed for the analysis of four cucurbitane triterpenoids (momordicoside L, momordicoside K, momordicoside F₂ , and 3β,7β,25-trihydroxy cucurbita-5,23(E)-dien-19-al) in bitter melon juices. Variables affecting the extraction efficiency including different extraction solvents, volume of extraction solvent, salt amount, acid condition, vortex speed and time were optimized thoroughly. Under the optimum conditions, precision was determined by the intra- and inter-day tests in a range of 1.1-5.7% and 2.9-4.0% (RSD), respectively, with recoveries between 95.7 and 106.1%. The calibration curves showed good linearity with square correlation coefficient of 0.9936-0.9991 (evaporative light scattering detection) and 0.9858-0.9989 (MS). The detection limits ranged from 0.8-1.9 ng/mL (MS) to 3-10 ng/mL (evaporative light scattering detection) for these compounds. Enrichment factors of four target compounds were between 27 and 63 times. The proposed method was also used to determine the apparent solvent/water partition coefficients of analytes within the range of 53-120. The developed method can effectively enrich and quantify cucurbitane triterpenoids from bitter melon drinks.

Entada phaseoloides extract suppresses hepatic gluconeogenesis via activation of the AMPK signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

The seed of Entada phaseoloides (L.) Merr. (Entada phaseoloides) has been long used as a folk medicine for the treatment of Diabetes mellitus by Chinese ethnic minorities. Recent reports have demonstrated that total saponins from Entada phaseoloides (TSEP) could reduce fasting blood glucose in type 2 diabetic rats. However, the mechanism has not been fully elucidated. The aim of this study was to explore the underlying mechanisms of TSEP on type 2 Diabetes mellitus (T2DM).

MATERIALS AND METHODS

Primary mouse hepatocytes and HepG2 cells were used to investigate the effects of TSEP on gluconeogenesis. After treatment with TSEP, glucose production, genes expression levels of Glucose-6-phosphatase (G6pase) and Phosphoenoylpyruvate carboxykinase (Pepck) were detected. The efficacy and underlying mechanism of TSEP on AMP-activated protein kinase (AMPK) signaling pathway were determinated.

RESULTS

TSEP significantly inhibited glucose production and the gluconeogenic gene expression. Treatment with TSEP elevated the phosphorylation of AMPK, which in turn promoted the phosphorylation of acetyl coenzyme A (ACC) and Akt/glycogen synthase kinase 3β (GSK3β), respectively. Furthermore, TSEP reduced lipid accumulation and improved insulin sensitivity in hepatocytes.

CONCLUSION

These findings provide evidence that TSEP exerts an antidiabetic effect by suppressing hepatic gluconeogenesis via the AMPK signaling pathway.

Hypoglycemic effect of D-chiro-inositol in type 2 diabetes mellitus rats through the PI3K/Akt signaling pathway

In this investigation, a model of type 2 diabetes mellitus (T2DM) was used on Sprague-Dawley (SD) rats to clarify more details of the mechanism in the therapy of T2DM. D-chiro-inositol (DCI) was administrated to the diabetic rats as two doses [30, 60 mg/(kg·body weight·day)]. The biochemical indices revealed that DCI had a positive effect on hypoglycemic activity and promoted the glycogen synthesis. The rats in DCI high-dosage group had a blood glucose reduction rate of 21.5% after 5 weeks of treatment, and had insulin content in serum about 15.3 ± 2.37 mIU/L which was significantly decreased than diabetes control group. Real-time polymerase chain reaction (RT-PCR) results revealed that DCI gave a positive regulation on glycogen synthase (GS) and protein glucose transporter-4 (Glut4). Western blotting suggested that DCI could up-regulated the expression of the phosphatidylinositol-3-kinase (PI3K) p85, PI3Kp110, GS as well as the phosphorylation of protein kinase B (Akt) both in the liver and the skeletal muscle. The results also revealed that DCI enhanced the Glut4 expression on skeletal muscle. Above all, DCI played a positive role in regulating insulin-mediated glucose uptake through the PI3K/Akt signaling pathway in T2DM rats.

Medicinal plants used in the traditional management of diabetes and its sequelae in Central America: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Globally 387 million people currently have diabetes and it is projected that this condition will be the 7th leading cause of death worldwide by 2030. As of 2012, its total prevalence in Central America (8.5%) was greater than the prevalence in most Latin American countries and the population of this region widely use herbal medicine. The aim of this study is to review the medicinal plants used to treat diabetes and its sequelae in seven Central American countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama.

MATERIALS AND METHODS

We conducted a literature review and extracted from primary sources the plant use reports in traditional remedies that matched one of the following disease categories: diabetes mellitus, kidney disease, urinary problems, skin diseases and infections, cardiovascular disease, sexual dysfunctions, visual loss, and nerve damage. Use reports were entered in a database and data were analysed in terms of the highest number of use reports for diabetes management and for the different sequelae. We also examined the scientific evidence that might support the local uses of the most reported species.

RESULTS

Out of 535 identified species used to manage diabetes and its sequelae, 104 species are used to manage diabetes and we found in vitro and in vivo preclinical experimental evidence of hypoglycaemic effect for 16 of the 20 species reported by at least two sources. However, only seven of these species are reported in more than 3 studies: Momordica charantia L., Neurolaena lobata (L.) R. Br. ex Cass., Tecoma stans (L.) Juss. ex Kunth, Persea americana Mill., Psidium guajava L., Anacardium occidentale L. and Hamelia patens Jacq. Several of the species that are used to manage diabetes in Central America are also used to treat conditions that may arise as its consequence such as kidney disease, urinary problems and skin conditions.

CONCLUSION

This review provides an overview of the medicinal plants used to manage diabetes and its sequelae in Central America and of the current scientific knowledge that might explain their traditional use. In Central America a large number of medicinal plants are used to treat this condition and its sequelae, although relatively few species are widely used across the region. For the species used to manage diabetes, there is variation in the availability and quality of pharmacological, chemical and clinical studies to explain traditional use.

Traditional plants used for the treatment of diabetes mellitus in Sursagar constituency, Jodhpur, Rajasthan - An ethnomedicinal survey

ETHNOPHARMACOLOGICAL RELEVANCE

In Jodhpur, large number of people suffering with non-insulin dependent diabetes mellitus (type 2 diabetes). They are using medicinal plants along with modern medicine for the management of diabetes. The aim of this work is to document the anti-diabetic plants and determine the most relevant anti-diabetic plant species using the Disease Consensus Index.

MATERIALS AND METHODS

Ethnomedicinal survey was conducted for selection of anti-diabetic plant. Structured questionnaire was developed for calculation of Disease Consensus Index and administered to fifty Type 2 diabetic patients for recording their response.

RESULTS

Twenty-one species of anti-diabetic plants were recorded, Momordica charantia (score: 0.71), Azadirachta indica (score: 0.64), Trigonella foenum-graecum (score: 0.63), Capparis decidua (score: 0.60), Withania coagulans (score: 0.54), Gymnema sylvestre (score: 0.52) and Syzygium cumini (score: 0.51) were the most significant anti-diabetic plants of the area of study, having DCI more than 0.5.

CONCLUSIONS

Use of anti-diabetic plants is prevalent diabetic patients of the area. C. decidua, W. coagulans and G. sylvestre are recommend the further phytochemical and pharmacological investigation due to high DCI score and relatively unexplored status.