Evidence-based Critical Evaluation of Glycemic Potential of Cynodon dactylon

Phytochemical analysis, antioxidant, acetylcholinesterase, and α-amylase inhibitors from extract

OBJECTIVE

To investigate the effects of Hippeastrum hybridum (HH) as a free radical scavenger, and an inhibitor of the two enzymes i-e Alpha-amylase (α-amylase) and acetylcholinesterase (AChE).

METHODS

In this study, HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant, anti-α-amylase, and anti-AChE efficiency via standard procedures.

RESULTS

Phytochemical analysis shows the existence of different compounds; while Coumarins and quinones were absent. The total phenolic, flavonoid, and tannins content were found to be (78.52 ± 0.69) mg GAE/g, (2.01 ± 0.04) mg RUE/g, and (58.12 ± 0.23) mg TAE/g of plant extract respectively. 28.02% ± 0.02% alkaloid and 2.02% ± 0.05% saponins were present in the HH extract. The HH extract showed the anti-oxidant property with IC50 (50% inhibition) of (151.01 ± 0.13) (HH), (79.01 ± 0.04) (Ascorbic acid) for ferric reducing, (91.48 ± 0.13) (HH), (48.02 ± 0.11) (Ascorbic acid) against Ammonium molybdenum, (156.02 ± 0.31) (HH), (52.38 ± 0.21) (Ascorbic acid) against DPPH, 136.01 ± 0.21 (HH), 52.02± 0.31 (Ascorbic acid) against H2O2, and 154.12 ± 0.03 (HH), (40.05 ± 0.15) (Ascorbic acid) μg/mL against ABTS respectively. Statistical analysis indicated that HH caused a competitive type of inhibition of α-amylase (Vmax remained constant and Km increases from 10.65 to 84.37%) while Glucophage caused the un-competitive type of inhibition i-e both Km and Vmax decreased from 40.49 to 69.15% and 38.86 to 69.61% respectively. The Ki, (inhibition constant); KI, (dissociation constant), Km, (Michaelis-Menten constant), and IC50 were found to be 62, 364, 68.1, and 38.08 ± 0.22 for HH and 12, 101.05, 195, 34.01 ± 0.21 for Glucophage. Similarly, HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while Vmax decreases from 60.5% to 74.1%. The calculated Ki, KI, Km, and IC50 were found to be 32, 36.2, 0.05, and 18.117 ± 0.018.

CONCLUSION

From the current results, it is concluded that HH extract contains bioactive compounds, and could be a good alternative to controlling oxidants, Alzheimer's and Type-II diabetic diseases.

Investigation of alpha amylase inhibitors from Bidens pilosa L. by in silico and in vitro studies

Bidens pilosa L. has been traditionally used as an anti-diabetic herbal medicine; however, its mechanism of action remains elusive. In this study, the potential role of B. pilosa compounds on alpha-amylase inhibition and regulation of multiple pathways was investigated via computational and experimental studies. The phytocompounds were retrieved from plant databases and published literature. The druggability profile of these compounds was predicted using MolSoft. The probable targets of these phytocompounds were predicted using BindingDB (similarity index ≥ 0.7). Further, compound-gene set-pathway and functional enrichment analysis were performed using STRING and KEGG pathway databases. The network between compound-protein-pathway was constructed using Cytoscape. Molecular docking was performed using AutoDock Vina, executed through the POAP pipeline. The stability of the best docked complex was subjected to all-atom molecular dynamics (MD) simulation for 100 ns to investigate their structural stabilities and intermolecular interactions using GROMACS software. Finally, B. pilosa hydroalcoholic extract was subjected to LC-MS and tested for dose- and time-dependent alpha-amylase inhibitory activity. Out of 31 bioactive compounds, 13 were predicted to modulate the human pancreatic alpha-amylase (AMY2A) and 12 pathways associated with diabetes mellitus. PI3K-Akt signaling pathway (hsa04151) scored the lowest false discovery rate by triggering 15 genes. Further intermolecular interaction analysis of the docked complex revealed that Brassidin had the highest active site interaction and lowest binding energy compared to standard acarbose, and MD reveals the formation of a stable complex throughout 100 ns production run. LC-MS analysis revealed the presence of 13 compounds (targeting AMY2A) in B. pilosa hydroalcoholic extract, which showed potent AMY2A inhibition by in vitro studies that corroborate in silico findings for its anti-diabetic activity. Based on these findings, enriched fractions/pure compounds inhibitory activity that can be performed in future for drug discovery.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-023-00187-9.

LC/MS-MS Analysis of Phenolic Compounds in Hyoscyamus albus L. Extract: In Vitro Antidiabetic Activity, In Silico Molecular Docking, and In Vivo Investigation against STZ-Induced Diabetic Mice

This study aimed to investigate the chemical composition and antidiabetic properties of cultivated Hyoscyamus albus L. The ethanol extract was analyzed using LC-MS/MS, and 18 distinct phenolic compounds were identified. Among these, p-coumaric acid (6656.8 ± 3.4 µg/g), gallic acid (6516 ± 1.7 µg/g), luteolin (6251.9 ± 1.3 µg/g), apigenin (6209.9 ± 1.1 µg/g), and rutin (5213.9 ± 1.3 µg/g) were identified as the most abundant polyphenolic molecules. In the in vitro antidiabetic experiment, the ability of the plant extract to inhibit α-glucosidase and α-amylase activities was examined. The results indicated that the extract from H. albus L. exhibited a higher inhibitory effect on α-amylase compared to α-glucosidase, with an IC50 of 146.63 ± 1.1 µg/mL and 270.43 ± 1.1 µg/mL, respectively. Docking simulations revealed that luteolin, fisetin, and rutin exhibited the most promising inhibitory activity against both enzymes, as indicated by their high contrasting inhibition scores. To further investigate the in vivo antidiabetic effects of H. albus L., an experiment was conducted using STZ-induced diabetic mice. The results demonstrated that the plant extract effectively reduced the levels of cholesterol and triglycerides. These findings suggest that H. albus L. may have therapeutic potential for managing hyperlipidemia, a common complication associated with diabetes. This highlights its potential as a natural remedy for diabetes and related conditions.

Combined effects of yacon flour and probiotic yogurt on the metabolic parameters and inflammatory and insulin signaling proteins in high-fat-diet-induced obese mice

BACKGROUND

Prebiotics and probiotics may be effective dietary components that can alter the gut microbiota of the host and, consequently, overcome imbalances associated with obesity. This work aimed to evaluate the synergistic and isolated effects and mechanisms by which probiotic yogurt containing Bifidobacterium animalis and/or Lactobacillus acidophilus and yacon flour alter metabolic parameters and inflammatory and insulin signaling proteins in diet-induced obese mice. Swiss mice were fed a high-fat diet (n = 48) or a standard diet (control; n = 6) for 56 days. The 42 mice that gained the most weight were selected and divided into seven groups that received different combinations of probiotic yogurt and yacon flour. After 30 days, biochemical parameters (blood glucose, serum total cholesterol, and triacylglycerols), crude fat excretion in feces, and periepididymal fat were assessed and an immunoblotting analysis of insulin signaling proteins and interleukin-1β was conducted.

RESULTS

The combination of yacon flour and a yogurt with two strains of probiotics exerted positive effects on the parameters evaluated, such as decreased body weight (-6.5%; P < 0.05), fasting glucose (-23.1%; P < 0.05), and triacylglycerol levels (-21.4%; P < 0.05) and decreased periepididymal fat accumulation (-44.2%; P < 0.05). There was a decrease in inflammatory markers (P < 0.001) and an improvement in insulin signaling (P < 0.001).

CONCLUSIONS

The combination of a prebiotic with two strains of probiotics in a food matrix may exert a protective effect against obesity-associated inflammation, improving insulin resistance, even in the short term. © 2022 Society of Chemical Industry.

Phytochemical analysis and inhibitory effects of Calligonum polygonoides on pancreatic α-amylase and β-glucosidase enzymes

OBJECTIVES

To estimate the existence of phyto-chemicals and then to determine the antidiabetic activity against α-amylase and β-glucosidase inhibition .

METHODS

The study was carried out by following standard procedures.

RESULTS

Phytochemicals analysis indicated the presence of different phytochemicals. The total phenolic content was 6.055 mg GAE/g and the total flavonoid content was 5.706 mg RU/g in the plant extract. The total saponins, alkaloids, and tannins contents were (0.044%), (2.88%) and (2.862 nm) respectively. α-amylase inhibition activity of Calligonum polygonoides (CP) extract was 70% with IC50 of 610 μg/mL and that of β-gluco-sidase inhibition activity was 65% with IC50 of 640 µg/mL.

CONCLUSION

The findings reported for the first time the antidiabetes-promoting effects of an extract of CP, thus validating their promising anti-diabetes potential.

Identification of Bioactive Phytochemicals from Six Plants: Mechanistic Insights into the Inhibition of Rumen Protozoa, Ammoniagenesis, and α-Glucosidase

Simple Summary

Rumen protozoa have some contribution to feed digestibility in the rumen, but Entodinium, the most predominant genus, is the main culprit of inefficient nitrogen utilization in ruminants. Using chemical drugs, many studies have attempted to inhibit the rumen protozoa, but few of the approaches are either effective or practical. In this study, we investigated the nutritional and functional properties of Adansonia digitata (baobab), Flemingia macrophylla (waras tree), Kalimeris indica (Indian aster),Brassica rapa subsp. chinensis (bok choy), Portulaca oleracea (common purslane), and Calotropis gigantea (giant milkweed) for their potential as feed additives in animal husbandry. The plants were also analyzed for their major phytochemicals using reversed phase-high performance liquid chromatography (HPLC) and then evaluated for their ability to inhibit rumen protozoa, ammoniagenesis, and microbial α-glucosidase activity in vitro. C. gigantea inhibited the rumen protozoa and reduced the wasteful ammoniagenesis, thereby indicating improved nitrogen utilization. A. digitata also reduced the microbial α-glucosidase activity that can potentially contribute to rumen acidosis. The tested plants, especially C. gigantea and A. digitata, could be used as potential alternatives to chemicals or antibiotics to ensure sustainable and green animal husbandry.

Abstract

Rumen protozoa prey on feed-degrading bacteria synthesizing microbial protein, lowering nitrogen utilization efficiency in ruminants. In this in vitro study, we evaluated six plants (Adansonia digitata, Flemingia macrophylla, Kalimeris indica,Brassica rapa subsp. chinensis, Portulaca oleracea, and Calotropis gigantea) for their potential to inhibit rumen protozoa and identified the phytochemicals potentially responsible for protozoa inhibition. Rumen protozoa were anaerobically cultured in vitro in the presence of each plant at four doses. All of the tested plants reduced total rumen protozoa (p ≤ 0.05), but C. gigantea and B. rapa were the most inhibitory, inhibiting rumen protozoa by 45.6 and 65.7%, respectively, at the dose of 1.1 mg/mL. Scanning electron microscopy revealed a disruption of the extracellular structure of protozoa cells. Only C. gigantea also decreased the wasteful ammoniagenesis (p ≤ 0.05). Moreover, the A. digitata extract inhibited α-glucosidase activity by about 70% at 100 µg/mL. Reversed-phase high-performance liquid chromatography analysis detected quercetin, anthraquinone, 3-hydroxybenzoic acid, astragaloside, and myricetin in the tested plant leaves. These plants may hold potential as feed additives to reduce rumen protozoa and α- glucosidase activity. Future research is needed to identify the specific anti-protozoal compound(s), the effects on the rumen microbiome, and its fermentation characteristics.

Evaluation of a natural compound extracted from Dolichandrone atrovirens as a novel antioxidant agent using Caenorhabditis elegans

The compound methyl cinnamoyl catalpol (DAM-1) was isolated from the methanol extract of Dolichandrone atrovirens. Studies have already reported the antioxidant activity of Dolichandrone atrovirens bark extract, but till date the antioxidant activity of the isolated compound DAM-1, remains unexplored. The endogenous process of reactive oxygen species generation which leads to various degenerative diseases, can be broken down using these exogenous moieties from plant origin, herein this study we sought to evaluate the antioxidant potential of the DAM-1 compound using Caenorhabditis elegans (C. elegans), which is the primary model to study the antioxidant activity of compounds. Cytotoxicity assay results showed that DAM-1 treatment in the concentration of 10, 25 and 50 μg/ml has shown 100%, 91%, and 50% survival respectively with overall p<0.0001 (treatment v/s control group). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide-Formazan (MTT) assay results showed that treatment had better survival rates than the control group at different time intervals i.e. 48 h, and 72 h with p<0.01. Mechanosensation (behavioral study) as well as in vivo study results showed that at 0 h, 10 μg/ml of DAM-1 treatment showed a better anti-oxidative activity than the control group, 25 and 50 μg/ml of DAM-1 treated groups with p<0.001 but at 2.5 h incubation with 10, 25, 50 μg/ml of DAM-1 showed an increased anti-oxidative activity than the control group with p<0.001. Thermoresistance assay confirmed that the treatment group had more survival than control group with p<0.001. Absorption study of DAM-1 in C. elegans has shown that the absorption of the drug increases up to 180 mins with a slight decrease after 360 mins and then constant absorption up to 1440 mins. This study paves the way towards the initiative to explore the pharmacological role of DAM-1 in various oxidative stress mediated diseases at molecular levels and the absorption study points out its potential role which could be utilized in the metabolomics and proteomics analysis of this compound in other studies.

Investigation of the In Vitro Antioxidant Potential Of Polyphenolic-Rich Extract of Artocarpus heterophyllus Lam Stem Bark and Its Antidiabetic Activity In Streptozotocin-Induced Diabetic Rats

Artocarpus heterophyllus Lam (Moraceae) stem bark has been used locally in managing diabetes mellitus with sparse scientific information. This study investigates the in vitro antioxidant potential of polyphenolic-rich extract of A heterophyllus stem bark as well as its antidiabetic activity in streptozotocin-induced diabetic rats. Fifty male Wistar rats were used with the induction of diabetes by a single intraperitoneal injection of streptozotocin (45 mg/kg body weight) and were orally administered 400 mg/kg free and bound phenols of A heterophyllus stem bark. The animals were sacrificed on the 28th day of the experiment using the cervical dislocation method; antihyperglycemia and anti-inflammatory parameters were subsequently assessed. The polyphenolic extracts demonstrated antioxidant potentials (such as hydrogen peroxide and diphenyl-1-picrylhydrazyl), as well as strong inhibitory activity against amylase and glucosidase. There was a significant (P < .05) increase in glycogen, insulin concentration, pancreatic β-cell scores (HOMA-β), antioxidant enzymes and hexokinase activities, as well as glucose transporter concentration in diabetic animals administered the extracts and metformin. Also, a significant (P < .05) reduction in fasting blood glucose, lipid peroxidation, glucose-6-phosphatase, and all anti-inflammatory parameters were observed in diabetic rats administered the extracts and metformin. The extracts demonstrated antidiabetic potential, which may be useful in the management of diabetes mellitus

In silico docking studies of α-amylase inhibitors from the anti-diabetic plant Leucas ciliata Benth. and an endophyte, Streptomyces longisporoflavus

In this investigation, potential inhibitors of α-amylase, one of the key regulatory enzymes in diabetes were characterized from the methanolic extract of Leucas ciliata Benth. (Lamiaceae), a traditional medicinal plant of the Western Ghats, southern India and the ethyl acetate extract of Streptomyces longisporoflavus (JX965948), an endophytic actinomycete isolated from the stem fragments of L. ciliata, by Gas Chromatography and Mass Spectroscopy (GC-MS) technique followed by molecular docking studies. Forty-four compounds were detected in the solvent extracts of the host plant and the endophyte, respectively. These compounds were selected as ligands for the receptor α-amylase in the molecular docking studies using PyRx software (0.8 V) for the inhibition of α-amylase activity. The ligands were ranked based on the binding energies ranging between - 3.1 and - 10.1 kcal/mol. Three ligands from the host plant extract, viz., Topotecan (PNo_7), Cathine (PNo_17) and 2,5-dimethoxy-4-(methylsulfonyl)amphetamine (PNo_18), depicted good binding energies of - 5.2 to - 7.8, respectively, whereas seven compounds from the endophyte extract showed binding energies in the range of - 4.7 to - 10.1, respectively. The standard α-amylase inhibitor Acarbose™ depicted binding energy of - 9.2 kcal/mol. All ligands were subjected to lead-likeliness property using Lipinski's rule of five. On the basis of the hydrogen bonding interactions with the receptor, and chemoinformatics analysis for drug-likeliness, one ligand, Topotecan (PNo_7) from the host plant was identified as the potential α-amylase inhibitor. This is the first attempt to identify alkaloid and flavonoid compounds as the α-amylase inhibitors from the host plant and its endophyte simultaneously. The molecular docking analyses presented in this study could lead to the development of potent α-amylase inhibitors helpful in the treatment of diabetes.

SUPPLEMENTARY INFORMATION

The online version of this article (10.1007/s13205-020-02547-0) contains supplementary material, which is available to authorized users.

Antiamylase, Antilipase, Antimicrobial, and Cytotoxic Activity of Nonea obtusifolia (Willd.) DC. from Palestine

Background

Medicinal plants are widely used in many cultures, traditions, and civilizations worldwide. Plants with high contents of the valuable biological compounds can efficiently cure many diseases. This study is aimed at assessing, for the first time, the anti-α-amylase, antilipase, antimicrobial, and cytotoxic activities of Nonea obtusifolia (Willd.) DC. of five extracts from Palestine.

Methods

The antimicrobial activity was estimated using well diffusion method for N. obtusifolia plant of five extracts against eight ATCC (American Type Culture Collection) and clinical isolates. The cytotoxic effects for these extracts were evaluated against HeLa (cervical) carcinoma cells using MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. Moreover, the lipase and α-amylase inhibitory properties were determined using standard biomedical assays.

Results

The acetone extract of N. obtusifolia plant showed a more potent α-amylase inhibitory compared with acarbose with IC₅₀ values of 25.7 ± 0.08 and 28.18 ± 1.22 μg/ml, respectively. Additionally, the acetone and methanol extracts revealed moderate antilipase activity compared to orlistat with IC₅₀ values of 30.19 ± 0.11, 33.11 ± 0.13, and 12.3 ± 0.35 μg/ml, respectively. The methylene chloride extract was found to inhibit the growth of all the tested bacterial and fungal strains and also found to have potential cytotoxic effect against HeLa cancer cell line.

Conclusion

This research work reports for the first time the biological activity of N. obtusifolia from Palestine, and the results were promising indicating that N. obtusifolia extracts contain valuable bioactive molecules that have a potential anti-α-amylase, antilipase, antibacterial, and antifungal cytotoxic potentials. Therefore, N. obtusifolia could have a medical significance in the future.

Aqueous extract of Tamarindus indica fruit pulp exhibits antihyperglycaemic activity

OBJECTIVE

Tamarindus indica Linn. (T.indica) is a well-known plant used in traditional medicine. The plant is popular for its antidiabetic activity. However, effect so f its aqueous fruit pulp extract on carbohydrate hydrolyzing enzymes and its glucose uptake potential were not explored.

MATERIALS AND METHODS

The antidiabetic activity was assessed by in-vitro α-amylase and α-glucosidase inhibitory assays after preliminary phytochemical analysis. MTT assay was carried out to find cytotoxicity. Glucose uptake activity of the extract was carried out using L6 myotubes.

RESULTS

The results showed a strong α-amylase inhibitory activity for the fruit pulp extract of T.indica compared to standard acarbose; the IC₅₀ of the fruit pulp extract of T.indica and acarbose was 34.19 µg/ml 34.83µM. The extract also showed moderate α-glucosidase inhibitory activity. IC₅₀ of the fruit pulp extract of T.indica and acarbose were 56.91µg/ml and 45.69µM respectively. The cytotoxicity assay showed IC₅₀ of >300µg/ml and ≥1000µM for the fruit pulp extract of T.indica and metformin. The extract showed 63.99±0.08% glucose uptake in L6 myotubes whereas metformin and insulin at 10µg/ml and 10µM exhibited an uptake of 76.99±0.3% and 84.48±0.45% glucose, respectively.

CONCLUSION

The study revealed that the fruit pulp extract of T.indica Linn does not show any cytotoxic effect and has very good α-amylase and good α-glucosidase inhibitory activities. The glucose uptake potential proves its postprandial hypoglycemic effect. Hence, it may be considered an antidiabetic agent for control of postprandial hyperglycemia.

Inhibition of Pancreatic α-amylase by Resveratrol Derivatives: Biological Activity and Molecular Modelling Evidence for Cooperativity between Viniferin Enantiomers

To improve the current understanding of the role of stilbenoids in the management of diabetes, the inhibition of the pancreatic α-amylase by resveratrol derivatives was investigated. To approach in a systematic way, the mechanistic and structural aspects of the interaction, potential bioactive agents were prepared as single molecules, that were used for the biological evaluation of the determinants of inhibitory binding. Some dimeric stilbenoids-in particular, viniferin isomers- were found to be better than the reference drug acarbose in inhibiting the pancreatic α-amylase. Racemic mixtures of viniferins were more effective inhibitors than the respective isolated pure enantiomers at an equivalent total concentration, and displayed cooperative effects not observed with the individual enantiomers. The molecular docking analysis provided a thermodynamics-based rationale for the measured inhibitory ability and for the observed synergistic effects. Indeed, the binding of additional ligands on the surface of the alpha-amylase was found to decrease the dissociation constant of inhibitors bound to the active site of the enzyme, thus providing a mechanistic rationale for the observed inhibitory synergies.

Maltase-glucoamylase inhibition potency and cytotoxicity of pyrimidine-fused compounds: An in silico and in vitro approach

The prevalence of diabetes mellitus has been incremented in the current century and the need for novel therapeutic compounds to treat this disease has been significantly increased. One of the most promising approaches is to inhibit intestinal alpha glucosidases. Based on our previous studies, four pyrimidine-fused heterocycles (PFH) were selected as they revealed satisfactory inhibitory action against mammalian α-glucosidase. The interaction of these compounds with both active domains of human maltase-glucoamylase (MGAM) and their effect on human Caco-2 cell line were investigated. The docking assessments suggested that binding properties of these ligands were almost similar to that of acarbose by establishing hydrogen bonds especially with Tyr1251 and Arg526 in both C-terminal and N-terminal MGAM, respectively. Also, these compounds indicated a stronger affinity for C-terminal of MGAM. L2 and L4 made tightly complexes with both terminals of MGAM which in turn revealed the importance of introducing pyrimidine scaffold and its hinge compartment. The results of molecular dynamics simulation analyses confirmed the docking data and showed deep penetration of L2 and L4 into the active site of MGAM. Based on cell cytotoxicity assessments, no significant cell death induction was observed. Hence, these functional MGAM inhibitors might be considered as new potential therapeutic compounds in treatment of diabetes and its complications.

In vitro antioxidant potential and inhibitory effect of hydro-ethanolic extract from African black velvet tamarind (Dialium indium) pulp on type 2 diabetes linked enzymes

The alarming rate of diabetes mellitus (DM) globally is bothersome and has drawn the search light of researchers on naturally endowed phytonutrients being an alternative in managing the menace. Therefore, the current study was designed to investigate some antioxidant parameters embedded in the extract of Dialium indium (DI) fruit pulp and also, to elucidate its antidiabetic potentials through the inhibition of two key carbohydrate-metabolizing enzymes such as α-amylase and intestinal α-glucosidase. Hydro-ethanolic extract of DI fruit pulp was used for the antioxidants and enzyme inhibitory bioassays through various convectional antioxidant assay methods in vitro. In the results, total phenolic content of the extract had; 6.74 ±3.38 mg GAE.g-1, total flavonoid contents; 0.02 ±0.01 mg QE.g-1 and FRAP; 0.84  ±0.47 mg AAE.g-1 dried sample. Also, there was a marked significant (p <0.05) difference observed in the inhibition of α-amylase and intestinal α-glucosidase by the different concentrations of the extract used in concentration-dependent manner with their different EC50. The inhibition demonstrated against these two carbohydrate metabolizing enzymes possibly could be through the embedded antioxidant potentials of the fruit pulp and this if properly harnessed, it could be helpful in the management of type 2 diabetes.

Alleviation of metabolic syndrome by monascin and ankaflavin: the perspective of Monascus functional foods

The metabolites of Monascus with multiple benefits are popular subjects for the development of functional foods. The yellow pigments, monascin and ankaflavin, which are the constituent metabolites of M. purpureus, M. pilosus and M. ruber, are becoming the focus of research on Monascus. Monascin and ankaflavin are azaphilone compounds with similar structures that exhibit multiple beneficial effects including anti-inflammation, anti-oxidation, anti-diabetes, immunomodulation, attenuation of Alzheimer's disease risk factor, and anti-tumorigenic effects. Monascin and ankaflavin not only possess pleiotropic bioactivities, but are also more potent than monacolin K in lowering lipid levels and have lower toxicity. Monascin and ankaflavin act as the activators of PPARγ agonist/Nrf-2 that subsequently ameliorate metabolic syndrome. Following the intensive exploration of Monascus bioactivities in recent years, the focus of research on Monascus-functional foods has shifted from whole fermented products/extracts to specific bioactive compounds. Therefore, the production of monascin and ankaflavin is an important topic with respect to Monascus-functional foods. Although several genomic studies have paved the way for understanding the production of secondary metabolites in Monascus, efforts are still required to effectively manipulate the biosynthesis of secondary metabolites with genetic engineering and/or culture techniques.

In-vitro α-amylase and α-glucosidase inhibitory activity of Adiantum caudatum Linn. and Celosia argentea Linn. extracts and fractions

Objective:

The objective of the present study was to provide an in-vitro evidence for the potential inhibitory activity of extracts and fractions of Adiantum caudatum Linn. and Celosia argentea Linn. on α-amylase and α-glucosidase enzymes.

Materials and Methods:

The plant extracts were prepared, first with cold maceration (70% v/v ethanol) and then by Soxhlation techniques (95% v/v ethanol). Subsequently, the combined extracts were subjected for fractionation. Different concentrations (0.1, 0.2, 0.3, 0.4, and 0.5 mg/ml) of extract and fractions were subjected to α-amylase and α-glucosidase inhibitory assay. The absorbance was measured at 540 and 405 nm using multiplate reader and the percentage of α- amylase and α- glucosidase inhibitory activity and IC₅₀ values of extract and fractions were calculated.

Results:

Fraction 2 of A. caudatum and fraction 4 of C. argentea has shown highest α-amylase and α-glucosidase inhibitory potential with IC₅₀ values of 0.241, 0.211 and 0.294, 0.249 mg/ml, respectively, which was comparable with acarbose (0.125 and 0.93 mg/ml). Whereas, extracts and remaining fractions of both the plants have shown lesser activity.

Conclusion:

The results of the present study indicate that, fraction 2 of A. caudatum, rich in triterpenoids and phenolics and fraction 4 of C. argentea, rich in flavonoids, are effective α- amylase and α- glucosidase inhibitors, which may be helpful to reduce the postprandial glucose levels. Hence, further studies may throw light on the antidiabetic potential of A. caudatum and C. argentea, especially in the management of type 2 diabetes.

Silymarin: A Novel Natural Agent to Restore Defective Pancreatic β Cells in Streptozotocin (STZ)-induced Diabetic Rats

This study aimed to investigate the potency of silymarin (SMN) and melatonin (MEL) on restoring the pancreatic   cells in streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were divided into five groups, including: control (C), untreated diabetic (D), SMN-treated diabetic (50 mg/Kg, orally), MEL-treated diabetic (10 mg/Kg, i.p.), and SMN plus MEL-treated diabetic rats. Diabetes was induced by injection of STZ (50 mg/Kg, i.p.). The blood glucose and insulin levels were measured. After the 28 days treatment period, antioxidant status was analyzed by determination of total antioxidant capacity (TAC) in the liver and serum. The histopathological changes in the pancreatic islets were examined by histochemical staining and enumeration of   cells. Although none of the test compounds reduced the blood glucose level to normal concentration, however SMN alone and in combination with MEL was able to decline it significantly (P<0.05) after 28 days administration. Both SMN and MEL could recover the diabetes-reduced TAC values. Moreover, the diabetes-induced cellular vacuolation and   cells depletion were improved by the SMN treatment. Our data suggest that the SMN and MEL treatment was able to normalize the antioxidant status, while only SMN administration could restore the  cells of Langerhans islets in diabetic rats.

In-vitro α-amylase and α-glucosidase inhibitory activity of Adiantum caudatum Linn. and Celosia argentea Linn. extracts and fractions

OBJECTIVE

The objective of the present study was to provide an in-vitro evidence for the potential inhibitory activity of extracts and fractions of Adiantum caudatum Linn. and Celosia argentea Linn. on α-amylase and α-glucosidase enzymes.

MATERIALS AND METHODS

The plant extracts were prepared, first with cold maceration (70% v/v ethanol) and then by Soxhlation techniques (95% v/v ethanol). Subsequently, the combined extracts were subjected for fractionation. Different concentrations (0.1, 0.2, 0.3, 0.4, and 0.5 mg/ml) of extract and fractions were subjected to α-amylase and α-glucosidase inhibitory assay. The absorbance was measured at 540 and 405 nm using multiplate reader and the percentage of α- amylase and α- glucosidase inhibitory activity and IC₅₀ values of extract and fractions were calculated.

RESULTS

Fraction 2 of A. caudatum and fraction 4 of C. argentea has shown highest α-amylase and α-glucosidase inhibitory potential with IC₅₀ values of 0.241, 0.211 and 0.294, 0.249 mg/ml, respectively, which was comparable with acarbose (0.125 and 0.93 mg/ml). Whereas, extracts and remaining fractions of both the plants have shown lesser activity.

CONCLUSION

The results of the present study indicate that, fraction 2 of A. caudatum, rich in triterpenoids and phenolics and fraction 4 of C. argentea, rich in flavonoids, are effective α- amylase and α- glucosidase inhibitors, which may be helpful to reduce the postprandial glucose levels. Hence, further studies may throw light on the antidiabetic potential of A. caudatum and C. argentea, especially in the management of type 2 diabetes.

Molecular approach to identify antidiabetic potential of Azadirachta indica

BACKGROUND

Azadirachta indica (Neem) is a medicinal plant, used in Ayurveda for treating various diseases, one of which is diabetes mellitus. It is known to possess antiinflammatory, antipyretic, antimicrobial, antidiabetic and diverse pharmacological properties. However, the molecular mechanism underlying the effect of A. indica on insulin signal transduction and glucose homeostasis is obscure.

OBJECTIVE

The aim was to study the effects of A. indica aqueous leaf extract on the expression of insulin signaling molecules and glucose oxidation in target tissue of high-fat and fructose-induced type-2 diabetic male rat.

MATERIALS AND METHODS

The oral effective dose of A. indica leaf extract (400 mg/kg body weight [b.wt]) was given once daily for 30 days to high-fat diet-induced diabetic rats. At the end of the experimental period, fasting blood glucose, oral glucose tolerance, serum lipid profile, and the levels of insulin signaling molecules, glycogen, glucose oxidation in gastrocnemius muscle were assessed.

RESULTS

Diabetic rats showed impaired glucose tolerance and impairment in insulin signaling molecules (insulin receptor, insulin receptor substrate-1, phospho-IRS-1(Tyr632), phospho-IRS-1(Ser636), phospho-Akt(Ser473), and glucose transporter 4 [GLUT4] proteins), glycogen concentration and glucose oxidation. The treatment with A. indica leaf extract normalized the altered levels of blood glucose, serum insulin, lipid profile and insulin signaling molecules as well as GLUT4 proteins at 400 mg/kg b.wt dose.

CONCLUSION

It is concluded from the present study that A. indica may play a significant role in the management of type-2 diabetes mellitus, by improving the insulin signaling molecules and glucose utilization in the skeletal muscle.

Protective effect of Monascus fermented rice against STZ-induced diabetic oxidative stress in kidney of rats

In the present study, anti-diabetic activity and nephroprotective effect of MMFR was evaluated by using STZ-induced diabetic rats. Administration of MMFR at 100 and 200 mg/kg bw showed significant (P < 0.01) anti-hyperglycemic activity by lowering blood glucose level, HbA1C and increasing body weight. Altered lipid profiles in diabetic rats were restored to normal level on treatment with MMFR and showed significant (P < 0.01) decrease in the elevated levels of biochemical parameters. MMFR produced significant (P < 0.01) improvement in antioxidant levels in kidney. Food safety of MFR produced by using mutant Monascus purpureus 254 (MMFR) was evaluated for genotoxicity and oral acute toxicity. In Ames mutagenicity assay MMFR doesn't showed any toxicity to the test strain S. typhimurium till 5 mg/plate. Acute toxicity study also recorded no toxicity till the dose of 5,000 mg/kg bw. The study concluded that MMFR, not only possess anti-diabetic activity but also prevents nephropathy and hypercholesterolemia due to diabetes.

A novel PPARgamma agonist monascin's potential application in diabetes prevention

Edible fungi of the Monascus species have been used as traditional Chinese medicine in eastern Asia for several centuries. Monascus-fermented products possess a number of functional secondary metabolites, including the anti-inflammatory pigments monascin and ankaflavin. Monascin has been shown to prevent or ameliorate several conditions, including hypercholesterolemia, hyperlipidemia, diabetes, and obesity. Recently, monascin has been shown to improve hyperglycemia, attenuate oxidative stress, inhibit insulin resistance, and suppress inflammatory cytokine production. In our recent study, we have found that monascin is a peroxisome proliferator-activated receptor-gamma (PPARgamma) agonist. The PPARgamma agonist activity had been investigated and its exerted benefits are inhibition of inflammation in methylglyoxal (MG)-treated rats, prevention of pancreas impairment causing advanced glycation endproducts (AGEs), promotion of insulin expression in vivo and in vitro, and attenuated carboxymethyllysine (CML)-induced hepatic stellate cell (HSC) activation in the past several years. Moreover, our studies also demonstrated that monascin also activated nuclear factor-erythroid 2-related factor 2 (Nrf2) in pancreatic RIN-m5F cell line thereby invading methylglyoxal induced pancreas dysfunction. In this review, we focus on the chemo-preventive properties of monascin against metabolic syndrome through PPARgamma and Nrf2 pathways.

Angiogenic effect of the aqueous extract of Cynodon dactylon on human umbilical vein endothelial cells and granulation tissue in rat

Background

Cynodon dactylon, a valuable medicinal plant, is widely used in Iranian folk medicine for the treatment of various cardiovascular diseases such as heart failure and atherosclerosis. Moreover, its anti-diabetic, anti-cancer and anti-microbial properties have been also reported. Concerning the critical role of angiogenesis in the incidence and progression of tumors and also its protective role in cardiovascular diseases, we investigated the effects of the aqueous extract prepared from the rhizomes of C. dactylon on vascular endothelial growth factor (VEGF) expressions in Human Umbilical Vein Endothelial Cells (HUVECs) and also on angiogenesis in carrageenan induced air-pouch model in rats.

Methods

In the air-pouch model, carrageenan was injected into an air-pouch on the back of the rats and following an IV injection of carmine red dye on day 6, granulation tissue was processed for the assessment of the dye content. Furthermore, in an in vitro study, angiogenic property of the extract was assessed through its effect on VEGF expression in HUVECs.

Results

Oral administration of 400 mg/kg/day of the extract significantly increased angiogenesis (p < 0.05) and markedly decreased neutrophil (p < 0.05) and total leukocyte infiltration (p < 0.001) into the granulation tissues. Moreover, the extract increased the expression of total VEGF in HUVECs at a concentration of (100 μl/ml).

Conclusion

The present study showed that the aqueous extract of C. dactylon promotes angiogenesis probably through stimulating VEGF expression.

Effects of silymarin on the pharmacokinetics of atorvastatin in diabetic rats

The effect of silymarin (SMN) on the pharmacokinetics of atorvastatin in diabetic rats was evaluated. Male Wistar rats were assigned into two major groups and then sub-grouped according to the purposes of the study. The first major group was subdivided into three groups (n = 6) including control, non-treated diabetic and SMN-treated diabetic animals. In the first major group, metabolism of testosterone by the hepatic microsomes was studied. The second major group also was divided to three groups including atorvastatin-treated non-diabetic, atorvastatin-treated diabetic and diabetic animals which received both atorvastatin and SMN. To study the pharmacokinetics of atorvastatin, serum samples were collected at 0, 3, 6, 12 and 24 h after the atorvastatin administration. Pharmacokinetic parameters were calculated using non-compartmental model. Streptozotocin-induced diabetes resulted in a remarkable induction of testosterone hydroxylation as the V max for 6β-hydroxytestosterone production in the diabetic rats (77.3 ± 8.6 pM/min/mg) was significantly higher than that in the control animals (45.9 ± 5.9 pM/min/mg). Moreover, SMN-treated animals showed a significant (P < 0.05) reduction of V max (59.4 ± 6.1 pM/min/mg). Diabetes resulted in a significant reduction of AUC (control 6.98 ± 0.58 vs diabetic rats 4.35 ± 0.24 h mg/ml) and C max values (control 0.52 ± 0.03 vs diabetic group 0.33 ± 0.01 μg/ml), while the SMN-received group showed remarkable recovery of diabetes-reduced values of AUC and C max. These findings indicated that diabetes resulted in a significant up-regulation of microsomal enzyme activities. Moreover, as SMN could significantly regulate the enzyme activities and consequently the atorvastatin pharmacokinetics in diabetic rats, its regulative effect in a combination therapy is concluded.

Molecular docking and inhibition kinetics of α-glucosidase activity by labdane diterpenes isolated from tora seeds (Alpinia nigra B.L. Burtt.)

Current approach against type 2 diabetes involves α-glucosidase inhibitors like acarbose associated with many side effects. Therefore, as an alternative to the existing drug, many natural products mainly from plant sources have been investigated which inhibit α-glucosidase. Here, we have selected medicinally important Alpinia nigra to explore its α-glucosidase inhibitory activity. Organic extracts of seeds and two purified natural diterpenes I: (E)-labda-8(17), 12-diene-15, 16-dial and II: (E)-8β, 17-epoxylabd-12-ene-15, 16-dial from A. nigra were investigated towards inhibition of α-glucosidase activity. Dose-dependent inhibition pattern were observed for seed extracts and both the compounds. Further, inhibition kinetics studies of the diterpenes indicated a non-competitive type of inhibition against α-glucosidase. Docking studies were carried out which revealed that both the diterpenes interacted within the active site of N-terminal and C-terminal domain of human maltase-glucoamylase enzyme, respectively. This is the first report of α-glucosidase inhibitory activity of these isolated diterpenes and their higher inhibitory potential than any terpenoids studied till date against α-glucosidase.

Characterisation of potential antidiabetic-related proteins from Pleurotus pulmonarius (Fr.) Quél. (grey oyster mushroom) by MALDI-TOF/TOF mass spectrometry

Pleurotus pulmonarius has been reported to have a potent remedial effect on diabetic property and considered to be an alternative for type 2 diabetes mellitus treatment. This study aimed to investigate the antidiabetic properties of ammonium sulphate precipitated protein fractions from P. pulmonarius basidiocarps. Preliminary results demonstrated that 30% (NH₄)₂SO₄ precipitated fraction (F30) inhibited Saccharomyces cerevisiae α-glucosidase activity (24.18%), and 100% (NH₄)₂SO₄ precipitated fraction (F100) inhibited porcine pancreatic α-amylase activity (41.80%). Following RP-HPLC purification, peak 3 from F30 fraction demonstrated inhibition towards α-glucosidase at the same time with meagre inhibition towards α-amylase activity. Characterisation of proteins using MALDI-TOF/TOF MS demonstrated the presence of four different proteins, which could be implicated in the regulation of blood glucose level via various mechanisms. Therefore, this study revealed the presence of four antidiabetic-related proteins which are profilin-like protein, glyceraldehyde-3-phosphate dehydrogenase-like protein, trehalose phosphorylase-like (TP-like) protein, and catalase-like protein. Hence, P. pulmonarius basidiocarps have high potential in lowering blood glucose level, reducing insulin resistance and vascular complications.

Phytochemical screening, physicochemical properties, acute toxicity testing and screening of hypoglycaemic activity of extracts of Eremurus himalaicus baker in normoglycaemic Wistar strain albino rats

In the present study EtOAc, MeOH, and aqueous extracts of Eremurus himalaicus were evaluated for hypoglycaemic effect in normal rats using both oral glucose tolerance test and 14-day oral administration study. Phytochemical and physicochemical screening was also done. In oral glucose tolerance test the aqueous and MeOH extracts of Eremurus himalaicus at a dose level of 500 mg/kg body weight prior to glucose load resulted in a significant fall in blood glucose level within 150 min. of glucose administration. The aqueous extract at a dose level of 250 mg/kg body weight and 500 mg/kg body weight also showed good hypoglycaemic response (P < 0.001); this was followed by MeOH extract at a dose level of 500 mg/kg body weight (P < 0.05), while MeOH extract at dose level of 250 mg/kg body weight and ethyl acetate extract at dose level of 250 mg/kg body weight and 500 mg/kg body weight exhibited insignificant effect. Phytochemical screening of extracts revealed the presence of alkaloids, terpenoids, phenolics, tannins, saponins, cardiac glycosides, and flavonoids. The results indicate that aqueous extract possess significant hypoglycaemic activity in normoglycaemic rats which may be attributed to the above-mentioned chemical constituents.

In vitro antidiabetic potential of the fruits of Crataegus pinnatifida

In an attempt to develop alternative medicine for the treatment of diabetes and related complications, the antidiabetic potential of the fruits of Crataegus pinnatifida was evaluated. The antidiabetic potential of the methanol (MeOH) extract as well as different solvent soluble fractions of the fruits of C. pinnatifida was evaluated via α-glucosidase, protein tyrosine phosphatase 1B (PTP1B), rat lens aldose reductase (RLAR), and advanced glycation end products (AGEs) formation inhibitory assays. The MeOH extract showed potent inhibitory activity against α-glucosidase, PTP1B, and AGEs formation with IC50 values of 122.11, 3.66 and 65.83 μg/ml respectively, while it showed moderate inhibitory activity against RLAR with the IC50 value of 160.54 μg/ml. Among different fractions, the ethyl acetate (EtOAc) and the dichloromethane (CH2Cl2) fractions were found as active fractions exhibiting potential α-glucosidase, PTP1B, RLAR inhibitory, and AGEs formation inhibitory activities. Seven compounds including hyperoside, chlorogenic acid, ursolic acid, oleanolic acid, 3-epicorosolic acid, β-sitosterol, β-sitosterol glucoside were isolated from these two fractions. 3-Epicorosolic acid showed both potent α-glucosidase and PTP1B inhibitory activities with IC50 values of 30.18 and 4.08 μg/ml respectively. Moreover, kinetic study revealed that 3-epicorosolic acid showed mixed type inhibition against PTP1B, while it showed uncompetitive inhibition against α-glucosidase. Therefore, these results suggest that the fruits of C. pinnatifida and its constituents have potential antidiabetic activity which might be used as a functional food for the treatment of diabetes and associated complications.

Potential Roles of Stevia rebaudiana Bertoni in Abrogating Insulin Resistance and Diabetes: A Review

Insulin resistance is a key factor in metabolic disorders like hyperglycemia and hyperinsulinemia, which are promoted by obesity and may later lead to Type II diabetes mellitus. In recent years, researchers have identified links between insulin resistance and many noncommunicable illnesses other than diabetes. Hence, studying insulin resistance is of particular importance in unravelling the pathways employed by such diseases. In this review, mechanisms involving free fatty acids, adipocytokines such as TNFα and PPARγ and serine kinases like JNK and IKKβ, asserted to be responsible in the development of insulin resistance, will be discussed. Suggested mechanisms for actions in normal and disrupted states were also visualised in several manually constructed diagrams to capture an overall view of the insulin-signalling pathway and its related components. The underlying constituents of medicinal significance found in the Stevia rebaudiana Bertoni plant (among other plants that potentiate antihyperglycemic activities) were explored in further depth. Understanding these factors and their mechanisms may be essential for comprehending the progression of insulin resistance towards the development of diabetes mellitus.

Use of laser-induced breakdown spectroscopy for the detection of glycemic elements in Indian medicinal plants

The demand for interdisciplinary research is increasing in the new millennium to help us understand complex problems and find solutions by integrating the knowledge from different disciplines. The present review is an excellent example of this and shows how unique combination of physics, chemistry, and biological techniques can be used for the evaluation of Indian medicinal herbs used for treating diabetes mellitus. Laser-induced breakdown spectroscopy (LIBS) is a sensitive optical technique that is widely used for its simplicity and versatility. This review presents the most recent application of LIBS for detection of glycemic elements in medicinal plants. The characteristics of matrices, object analysis, use of laser system, and analytical performances with respect to Indian herbs are discussed.

A Scientific Validation of Antihyperglycemic and Antihyperlipidemic Attributes of Trichosanthes dioica

The present study was undertaken to scientifically validate the antidiabetic activity of aqueous fruit extract of Trichosanthes dioica Roxb. (Family: Cucurbitaceae) which has been traditionally used for managing diabetes mellitus. This plant commonly known as "Sespadula" in English has not been explored scientifically so far for its glycemic potential except by our research group. The study was conducted with variable doses on normal, mild, and severe diabetics models, and several biochemical parameters including blood glucose level (BGL) were assessed. Maximum fall in BGL of 23.8% in normal rats and of 31.3% in mild diabetic rats was observed during their fasting blood glucose (FBG) and glucose tolerance test (GTT) with the dose of 1000 mg kg(-1). In severely diabetic animals after 4 weeks treatment with FBG, postprandial glucose, total cholesterol, and triglyceride levels were reduced by 28.7, 30.7, 57.2, and 18.5%, whereas high density lipoprotein, total protein, hemoglobin, and body weight were increased by 33.0, 36.7, 15.7 and 16.7%, respectively. Moreover, urine sugar was reduced from +4 to +1. Thus, the study scientifically validates the traditional use of T. diocia in diabetes management and could be developed as an effective oral agent for treating diabetes mellitus and complications associated with it.

Synthesis and glycosidase inhibitory activity of novel (2-phenyl-4H-benzopyrimedo[2,1-b]-thiazol-4-yliden)acetonitrile derivatives

A series of (2-phenyl-4H-benzopyrimodo[2,1-b][1,3]thiazol-4-yliden-4-yliden)acetonitrile derivatives have been prepared by ring transformation reaction of 4-(methylthio)-2-oxo-6-aryl-2H-pyrane-3-carbonitriles. The yield of ring transformation product is moderate to good. Furthermore the glycosidase inhibitory activities were tested by using α-amylase and α-glucosidase pancreatic, intestinal and liver enzymes, responsible for hyperglycemia in type II diabetes. The results revealed that all compounds exhibit significant glycosidase inhibitory activity.

Therapeutic potential of some plant extracts used in Turkish traditional medicine on streptozocin-induced type 1 diabetes mellitus in rats

Diabetes mellitus (DM) is known to impair many physiological functions. Some reports claim that medicinal plants can reduce these alterations caused by DM. The aim of this study was to investigate the therapeutic potential of aqueous-methanol extracts of Urtica dioica, Thymus vulgaris (TV), Myrtus communis (MC), Scolymus hispanicus (SH) and Cinnamomun zeylanicum (CZ) on streptozotocin (STZ)-induced type 1 DM in rats. Diabetes was induced via a single i.p. injection of STZ (65 mg/kg body weight). After 1 week to allow for development of diabetes, each plant extract was administered to diabetic rats separately at a dose of 100 mg/kg body weight daily for 28 days. The results showed that only SH extract significantly (P < 0.05) amended fasting blood glucose level. The lipid profile was ameliorated especially by supplementations of TV, MC and CZ extracts. Almost all plant extract treatments markedly (P < 0.05) increased reduced glutathione content and decreased lipid peroxidation levels of erythrocyte, plasma, retina and lens tissues. They also significantly (P < 0.05) amended erythrocyte catalase activity, levels of marker serum enzymes (except amylase), urea and blood urea nitrogen when compared to diabetic rats treated with nothing. Furthermore, none of the plant extracts counteracted body weight loss of diabetic rats. Our data revealed that the aforementioned plant extracts have remarkable potential to counteract DM-caused alterations, probably through their antioxidant and free radical-defusing effects.

Antidiabetic Effect of Morinda citrifolia (Noni) Fermented by Cheonggukjang in KK-A(y) Diabetic Mice

Antidiabetic effects of Morinda citrifolia (aka Noni) fermented by Cheonggukjang (fast-fermented soybean paste) were evaluated using a T2DM (type 2 diabetes mellitus) murine model. Six-week-old KK-Ay/TaJcl mice were randomly divided into four groups: (1) the diabetic control (DC) group, provided with a normal mouse diet; (2) the positive control (PC) group, provided with a functional health food diet; (3) the M. citrifolia (MC) group, provided with an MC-based diet; (4) the fermented M. citrifolia (FMC) group, provided with an FMC-based diet. Over a testing period of 90 days, food and water intake decreased significantly in the FMC and PC groups compared with the DC group. Blood glucose levels in the FMC group were 211.60–252.20 mg/dL after 90 days, while those in the control group were over 400 mg/dL after 20 days. In addition, FMC supplementation reduced glycosylated hemoglobin (HbA1c) levels, enhanced insulin sensitivity, and significantly decreased serum triglycerides and low-density lipoprotein (LDL) cholesterol. Furthermore, a fermented M. citrifolia 70% ethanolic extract (FMCE) activated peroxisome proliferator-activated receptor-(PPAR-) γ and stimulated glucose uptake via stimulation of AMP-activated protein kinase (AMPK) in cultured C2C12 cells. These results suggest that FMC can be employed as a functional health food for T2DM management.

Analysis of Modification of Liver Proteome in Diabetic Rats by 2D Electrophoresis and MALDI-TOF-MS

The uncontrolled hyperglycemia can lead to disturbances in the cell structure and functions of organs. This study was performed to analyze the "differential proteome" change in rat liver associated with diabetes mellitus in relation to effects of an anti-diabetic herb, Cynodon dactylon leaf extracts. Rats were intraperitoneally injected with alloxan (150 mg/kg/bw) and treated with C. dactylon leaf extracts (450 mg/kg/bw/day/orally). The liver proteins were subjected to proteome analysis using the advanced technologies i.e., 2D electrophoresis (2-DE) and mass spectrometry. Comparison of 2-DE protein distribution profiles among the livers from normal, alloxan-induced diabetic rats and alloxan-induced diabetic rats treated with C. dactylon leaves identified three proteins that were up-regulated in alloxan-induced diabetic rats i.e., nucleophosmin, l-xylulose reductase and carbonic anhydrase III which are known to be mainly involved in ribosome biogenesis, centrosome duplication, cell proliferation, tumor suppression, glucose metabolism, osmo-regulation, water-CO2 balance and acid-base balance. These results help us to understand the elucidation of molecular mechanism connected to liver function and insulin associated with diabetes mellitus. These identified proteins were primarily involved in cell proliferation and homoeostasis of liver tissues upon the treatment with C. dactylon leaf extracts.

Proteomic analysis of plasma proteins in diabetic rats by 2D electrophoresis and MALDI-TOF-MS

Despite tremendous advances in our understanding of the molecular basis of diabetes mellitus, substantial gaps still remain in our understanding of disease pathogenesis and in the development of effective strategies for early diagnosis and treatment. The proteomic approach has offered many opportunities and challenges in identifying new marker proteins and therapeutic targets, i.e., using 2D-polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionisation-time of flight mass spectrometry. The differential protein expressions were analyzed in alloxan-induced diabetic rats treated with Cynodon dactylon leaf extract. The plant extract was administered for 15 days that resulted in a significant increase in plasma insulin and C-peptide levels. We have also identified four differentially expressed proteins from rat plasma. These four diabetes-associated proteins were broadly classified into three groups as per their function: (1) lipid metabolism-associated protein (Apo A-IV), (2) antioxidant activity-related proteins [preprohaptoglobin and heat shock proteins B8 (HspB8)], and (3) muscle function-related protein (TPM3). Apo A-IV, HspB8, and preprohaptoglobin may play a key role in the recovery of diabetes mellitus and also prevent the diabetes-associated complications such as prevention of oxidative stress due to free radical and free hemoglobin. These results show the value of proteomic approach in identifying the potential markers that may eventually serve as diagnostic markers or therapeutic targets.

Monascin from red mold dioscorea as a novel antidiabetic and antioxidative stress agent in rats and Caenorhabditis elegans

Monascin is a major yellow compound from red mold dioscorea. We investigated monascin to test whether this compound acts as an antidiabetic and antioxidative stress agent in diabetic rats and Caenorhabditis elegans. The mechanisms by which monascin exerts its action in vivo were also examined. Streptozotocin (STZ)-induced diabetic rats were given monascin at 30 mg/kg/day and sacrificed after 8 weeks. Blood glucose and serum insulin, triglyceride, total cholesterol, and high-density lipoprotein and antioxidative enzymes in the pancreas of rats were measured. In addition, monascin was evaluated for stress resistance and potential associated mechanisms in C. elegans. Throughout the 8-week experimental period, significantly lowered blood glucose, serum triglyceride, and total cholesterol and higher high-density lipoprotein levels were observed in monascin-treated rats. Monascin-treated rats showed higher serum insulin level, lower reactive oxygen species production, and higher activities of glutathione peroxidase, superoxide dismutase, and catalase in the pancreas compared to diabetic control rats. In addition, monascin significantly induced the hepatic mRNA levels of FOXO3a, FOXO1, MnSOD, and catalase in STZ-induced diabetic rats. Monascin-treated C. elegans showed an increased survival rate during oxidative stress and heat stress treatments compared to untreated controls. Moreover, monascin extended the life span under high-glucose conditions and enhanced expression of small heat shock protein (sHSP-16.2), superoxide dismutase (SOD-3), and glutathione S-transferase (GST-4) in C. elegans. Finally, we showed that monascin affected the subcellular distribution of the FOXO transcription factor DAF-16, whereas it was unable to enhance oxidative stress resistance in the daf-16 deletion mutant in C. elegans. Mechanistic studies in rats and C. elegans suggest that the protective effects of monascin are mediated via regulation of the FOXO/DAF-16-dependent insulin signaling pathway by inducing the expression of stress response/antioxidant genes, thereby enhancing oxidative stress resistance.

Mosquitocidal and water purification properties of Cynodon dactylon, Aloe vera, Hemidesmus indicus and Coleus amboinicus leaf extracts against the mosquito vectors

Ethanolic extracts of Cynodon dactylon, Aloe vera, Hemidesmus indicus and Coleus amboinicus were tested for their toxicity effect on the third-instar larvae of Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. The leaves of C. dactylon, A. vera, H. indicus and C. amboinicus were collected from natural habitats (forests) in Western Ghats, Tamil Nadu, India. A total of 250 g of fresh, mature leaves were rinsed with distilled water and dried in shade. The dried leaves were put in Soxhlet apparatus and extract prepared using 100% ethanol for 72 h at 30-40°C. Dried residues were obtained from 100 g of extract evaporated to dryness in rotary vacuum evaporator. Larvicidal properties of ethanolic leaf extracts showed that the extracts are effective as mosquito control agents. The larval mortality was observed after 24 h exposure. No mortality was observed in the control. The median lethal concentration (LC(50)) values observed for the larvicidal activities are 0.44%, 0.51%, 0.59% and 0.68% for extracts of C. dactylon, A. vera, H. indicus and C. amboinicus, respectively. The observed mortality were statistically significant at P < 0.05 level. C. dactylon showed the highest mortality rate against the three species of mosquito larvae in laboratory and field. The selected plants were shown to exhibit water purification properties. Water quality parameters such as turbidity, pH and water clarity were analyzed in the water samples (pre-treatment and post-treatment of plant extracts) taken from the different breeding sites of mosquitoes. Water colour, turbidity and pH were reduced significantly after treatment with C. dactylon (13 HU, 31.5 mg/l and 6.9), H. indicus (13.8 HU, 33 mg/l and 7.1), A. vera (16 HU, 33.8 mg/l and 7.4) and C. amboinicus (21 HU, 35 mg/l and 7.5) extracts. The study proved that the extracts of C. dactylon, A. vera, H. indicus and C. amboinicus have both mosquitocidal and water sedimentation properties.

Antidiabetic Activity of Gnidia glauca and Dioscorea bulbifera: Potent Amylase and Glucosidase Inhibitors

Diabetes is a metabolic disorder affecting about 220 million people worldwide. One of the most critical complications of diabetes is post-prandial hyper-glycemia (PPHG). Glucosidase inhibitor and α-amylase inhibitors are class of compounds that help in managing PPHG. Low-cost herbal treatment is recommended due to their lesser side effect for treatment of diabetes. Two plants with significant traditional therapeutic potential, namely, Gnidia glauca and Dioscorea bulbifera, were tested for their efficiency to inhibit α-amylase and α-glucosidase. Stem, leaf, and flower of G. glauca and bulb of D. bulbifera were sequentially extracted with petroleum ether, ethyl acetate, and methanol as well as separately with 70% ethanol. Petroleum ether extract of flower of G. glauca was found to inhibit α-amylase significantly (78.56%). Extracts were further tested against crude murine pancreatic, small intestinal, and liver glucosidase enzyme which revealed excellent inhibitory properties. α-glucosidase inhibition provided a strong in vitro evidence for confirmation of both G. glauca and D. bulbifera as excellent antidiabetic remedy. This is the first report of its kind that provides a strong biochemical basis for management of type II diabetes using G. glauca and D. bulbifera. These results provide intense rationale for further in vivo and clinical study.