Management of type 2 diabetes mellitus by lifestyle, diet and medicinal plants

The effect of combining basil seeds and gum Arabic on the healing process of experimental acetic acid-induced ulcerative colitis in rats

Background & aim

Ulcerative colitis (UC) is a chronic recurrent inflammatory disease of the large intestine and rectum that oxidative stress and severe inflammation are the main features of this disease. Previous studies have shown that separate consumption of basil and gum arabic can reduce inflammation and oxidative stress. The aim of the study was evaluating the effect of treatment with basil seeds given together with gum arabic on healing, inflammation and oxidative stress in the course of experimental colitis in rats.

Experimental procedure

A total number of 50 male rats were used, randomly assigned to five groups of 10 rats each. Colitis was induced in rats by enemas with 4% solution od acetic acid. Four days after induction of colitis, rats were treated for next 4 days with saline or combination of basil seeds plus gum arabic (1 mg/kg) or sulfasalazine (100 mg/g) rectally. The experiment was terminated after last dose of treatment. Rats without induction of colitis were used as a sham group.

Results

Acetic acid-induced colitis increased the macroscopic and histopathological damage scores of the colon as well as colon levels of MDA(Malondialdehyde), MPO(Myeloperoxidase), TNFα(Tissue necrosis factor α), IL6 (Interleukin 6)and IL17(Interleukin 17) and decreased SOD(Superoxide Dismutase), GPx (Glutathione Peroxidase) and IL10 (Interleukin 10) levels compared with the control group(P < 0.001). Treatment with basil and gum arabic reduced macroscopic and histopathological damage scores (P < 0.01) of the colon, MDA, MPO, TNFα, IL6(P < 0.001) and IL17 (P < 0.01) levels of the colon and increased SOD, GPx and IL10 levels compared to the colitis group (P < 0.01).

Conclusion

Rectal administration of combination of basil seeds plus gum arabic after induction of colitis, exhibits antioxidant and anti-inflammatory effects, and accelerates the healing of the colon in experimental colitis evoked by acetic acid.

GC-MS- and NMR-Based Metabolomics and Molecular Docking Reveal the Potential Alpha-Glucosidase Inhibitors from Psychotria malayana Jack Leaves

Psychotria malayana Jack leaf, known in Indonesia as “daun salung”, is traditionally used for the treatment of diabetes and other diseases. Despite its potential, the phytochemical study related to its anti-diabetic activity is still lacking. Thus, this study aimed to identify putative inhibitors of α-glucosidase, a prominent enzyme contributing to diabetes type 2 in P. malayana leaf extract using gas chromatography-mass spectrometry (GC-MS)- and nuclear magnetic resonance (NMR)-based metabolomics, and to investigate the molecular interaction between those inhibitors and the enzyme through in silico approach. Twenty samples were extracted with different solvent ratios of methanol–water (0, 25, 50, 75, and 100% v/v). All extracts were tested on the alpha-glucosidase inhibition (AGI) assay and analyzed using GC-MS and NMR. Multivariate data analysis through a partial least square (PLS) and orthogonal partial square (OPLS) models were developed in order to correlate the metabolite profile and the bioactivity leading to the annotation of the putative bioactive compounds in the plant extracts. A total of ten putative bioactive compounds were identified and some of them reported in this plant for the first time, namely 1,3,5-benzenetriol (1); palmitic acid (2); cholesta-7,9(11)-diene-3-ol (3); 1-monopalmitin (4); β-tocopherol (5); α-tocopherol (6); 24-epicampesterol (7); stigmast-5-ene (8); 4-hydroxyphenylpyruvic acid (10); and glutamine (11). For the evaluation of the potential binding modes between the inhibitors and protein, the in silico study via molecular docking was performed where the crystal structure of Saccharomyces cerevisiae isomaltase (PDB code: 3A4A) was used. Ten amino acid residues, namely ASP352, HIE351, GLN182, ARG442, ASH215, SER311, ARG213, GLH277, GLN279, and PRO312 established hydrogen bond in the docked complex, as well as hydrophobic interaction of other amino acid residues with the putative compounds. The α-glucosidase inhibitors showed moderate to high binding affinities (−5.5 to −9.4 kcal/mol) towards the active site of the enzymatic protein, where compounds 3, 5, and 8 showed higher binding affinity compared to both quercetin and control ligand.

Association of dietary intake, medication and anthropometric indices with serum levels of advanced glycation end products, caspase-3, and matrix metalloproteinase-9 in diabetic patients

Background and objective

Increased serum levels of advanced glycation end products (AGEs), caspase-3 (Cas-3) and matrix metalloproteinase-9 (MMP-9) have been reported in diabetic patients. This study aimed to evaluate association of anthropometric, dietary, and therapeutic factors with serum levels of methylglyoxal (MGO), carboxymethyl lysine (CML), pentosidine (Pen), Cas-3, and MMP-9 in diabetic patients.

Methods

The current study included 36 diabetic subjects. Dietary intake of the participants was assessed using three-day 24-h recall survey and anthropometric indices were measured. Demographic factors and medication intake of every subject were obtained. Serum levels of CML, MGO, Pen, MMP-9, and Cas-3 were measured using ELISA method.

Results

Gliclazide consumption was positively correlated with MMP-9 and Cas-3, but not AGEs levels. Females had higher MGO level compared with males. Further, CML levels were negatively correlated with BMI and WHR. Dietary protein intake was positively correlated with MMP-9, Cas-3, and MGO levels. As well as dietary energy and fat intake had significant positive relationship with serum Cas-3 concentration.

Conclusion

It is concluded that anthropometric characteristics, dietary intake, and therapeutic medications are possible factors that may determine the circulating levels of AGEs, MMP-9, and Cas-3 in patients with diabetes.

Characterization of α-Glucosidase Inhibitors from Psychotria malayana Jack Leaves Extract Using LC-MS-Based Multivariate Data Analysis and In-Silico Molecular Docking

Psychotria malayana Jack has traditionally been used to treat diabetes. Despite its potential, the scientific proof in relation to this plant is still lacking. Thus, the present study aimed to investigate the α-glucosidase inhibitors in P.malayana leaf extracts using a metabolomics approach and to elucidate the ligand–protein interactions through in silico techniques. The plant leaves were extracted with methanol and water at five various ratios (100, 75, 50, 25 and 0% v/v; water–methanol). Each extract was tested for α-glucosidase inhibition, followed by analysis using liquid chromatography tandem to mass spectrometry. The data were further subjected to multivariate data analysis by means of an orthogonal partial least square in order to correlate the chemical profile and the bioactivity. The loading plots revealed that the m/z signals correspond to the activity of α-glucosidase inhibitors, which led to the identification of three putative bioactive compounds, namely 5′-hydroxymethyl-1′-(1, 2, 3, 9-tetrahydro-pyrrolo (2, 1-b) quinazolin-1-yl)-heptan-1′-one (1), α-terpinyl-β-glucoside (2), and machaeridiol-A (3). Molecular docking of the identified inhibitors was performed using Auto Dock Vina software against the crystal structure of Saccharomyces cerevisiae isomaltase (Protein Data Bank code: 3A4A). Four hydrogen bonds were detected in the docked complex, involving several residues, namely ASP352, ARG213, ARG442, GLU277, GLN279, HIE280, and GLU411. Compound 1, 2, and 3 showed binding affinity values of −8.3, −7.6, and −10.0 kcal/mol, respectively, which indicate the good binding ability of the compounds towards the enzyme when compared to that of quercetin, a known α-glucosidase inhibitor. The three identified compounds that showed potential binding affinity towards the enzymatic protein in molecular docking interactions could be the bioactive compounds associated with the traditional use of this plant.

Alfa glucosidase inhibitory, anti inflammatory activities and a new furanocoumarin derivative of Ruellia tuberosa

Rullia tuberosa L. is used for treatment of diabetes mellitus, anti-inflammation, etc. However, its hypoglycaemic and anti inflammatory activities has not been investigated so far. In the present study, the α-glucosidase inhibitory, anti inflammatory activities of the extract of this plant were investigated. Our results showed that the crude extract as well as ethyl acetate and methanol fractions showed α-glucosidase inhibitory activity with IC₅₀ of 15.84, 4.73 and 8.27 µg/ml, respectively. In addition, the hexane and ethyl acetate fractions are capable of inhibiting LPS-induced NO production with IC₅₀ of 17.41 and 23.95 µg/mL, respectively. From the ethyl acetate and methanol fractions, eight compounds, including isobargaptol 5-O-β-D-glucopyranoside (1), syringaresinol (2), catechin (3), pulmatin (4), stigmast-4-en-3-on (4), verbascoside (5), hydroxymethylfurfural (6), rutin (7), and homoplantaginin (8) were extracted and isolated. Their chemical structures were elucidated by spectroscopic method including MS, 1 D and 2 D- NMR and comparison with the literature values.

Effect of turmeric on glycemic status, lipid profile, hs-CRP, and total antioxidant capacity in hyperlipidemic type 2 diabetes mellitus patients

Diabetes mellitus is the most common metabolic disorder worldwide. This study examined the effect of turmeric supplementation on glycemic status, lipid profile, hs-CRP and total antioxidant capacity in hyperlipidemic type 2 diabetic patients. In this double-blind, randomized clinical trial, 80 hyperlipidemic type 2 diabetic patients were divided into turmeric (2,100 mg powdered rhizome of turmeric daily) and placebo groups for 8 weeks. Body weight, fasting plasma glucose, hemoglobin A1c (HbA1c), serum insulin, triglyceride (TG), total cholesterol, low density lypoprotein cholesterol (LDL-c), high density lypoprotein cholesterol, apolipoprotein A1, apolipoprotein B, high sensitivity C-reactive protein (hs-CRP), and total antioxidant capacity were measured before and after intervention. Statistical analysis was carried out using paired and independent t and chi-square tests. Seventy five patients completed the study. The turmeric group showed significant decreases in body weight, TG, and LDL-c compared with baseline (p value < 0.05). Body mass index, TG, and total cholesterol decreased significantly in the turmeric group compared with the placebo group (p value < 0.05). No significant changes were observed in other parameters between the two groups after intervention (p value < 0.05). Turmeric improved some fractions of lipid profile and decreased body weight in hyperlipidemic patients with type 2 diabetes. It had no significant effect on glycemic status, hs-CRP, and total antioxidant capacity in these patients.

Ocimum basilicum but not Ocimum gratissimum present cytotoxic effects on human breast cancer cell line MCF-7, inducing apoptosis and triggering mTOR/Akt/p70S6K pathway

Breast cancer is the major cause of death by cancer in women worldwide and in spite of the many drugs for its treatment, there is still the need for novel therapies for its control. Ocimum species have been used by traditional medicine to control several diseases, including cancer. We have previously characterized the antidiabetic properties of the unfractionated aqueous leaf extracts of Ocimum basilicum (OB) and Ocimum gratissimum (OG), modulating glucose metabolism in diabetic mice. Since glucose metabolism is primordial for cancer cells survival, we hypothesized that these extracts are effective against cancer cells. The unfractionated aqueous leaf extracts of OB and OG were chemically characterized and tested for their cytotoxic, cytostatic and anti-proliferative properties against the human breast cancer cell line MCF-7. Both extracts presented cytostatic effects with an 80% decrease in MCF-7 cell growth at 1 mg/mL. However, only OB promoted cytotoxic effects, interfering with the cell viability even after interruption of the treatment. Moreover, OB but not OG affected the cell proliferation and metabolism, evaluated in terms of lactate production and intracellular ATP content. After 24 h of treatment, OB treated cells presented an apoptotic profile, while OG treated cells were more necrotic. The treatment with both extracts also activated AMPK, but OB was much more efficient than OG in promoting this. The activation of mTOR signaling, another survival pathway was promoted by OB, whereas OG failed to activate it. In the end, we conclude that OB extract is efficient against the human breast cancer cell line.

Salicornia: evaluating the halophytic extremophile as a food and a pharmaceutical candidate

Food insecurity is a major issue in current scenario where a large section of mankind is at risk of insufficient diet. As food productivity has its limits, the prospecting of unutilized or underutilized flora as food candidates is collectively recognized as a sustainable option. In the past decade, a number of obscure plants have been identified to be rich in dietary components and deemed fit for integration into the food platter. This review discusses a candidate Salicornia, belonging to family Amaranthaceae. This halophyte has a broad geographical distribution, and phytochemical profiling has indicated its food relevance. An array of functional nutrients as fibers, polyphenols, and flavonoids have been detected in Salicornia. Though high salt, oxalate and saponin content in the plants are anti-nutrients, they can be removed to justify usage of Salicornia as a ‘sea vegetable’. Apart from culinary relevance, medicinal attributes like immunomodulatory, lipid-lowering, antiproliferative, osteoprotective, and hypoglycemic render this lesser-known marsh plant significant for phytochemical studies. This appraisal is expected to be useful towards further research and popularization of this extremophile halophyte.

Hypoglycemic effect of Brassica juncea (seeds) on streptozotocin induced diabetic male albino rat

OBJECTIVE

To evaluate the hypoglycemic effect of Brassica juncea (seeds) on streptozotocin induced diabetic male albino rats.

METHODS

Hypoglycemic activity of Brassica juncea (seeds) aqueous extract at a dose of 250, 350 and 450 mg/kg body weight was evaluated. Adult male Swiss albino rats of six numbers in each group was undertaken for study and evaluated.

RESULTS

The serum insulin levels were recorded a significant depletion in all groups, short term as well as long term diabetic animals, when compared to that of normal animals. A significant dosage dependent augmenting effect of the seed extract on the serum insulin was recorded in both short term as well as long term groups.

CONCLUSIONS

The aqueous seed extract of Brassica juncea has potent hypoglycemic activity in male albino rat.

Endocrinological analysis of endothelium-dependent vasodilation in middle-aged patients with impaired glucose tolerance during prediabetes mellitus

Impaired glucose tolerance (IGT) is a pre-diabetic metabolic state involving heterogeneous and dynamic changes between the normal and diabetic state. The present study aimed to investigate the endocrine regulation of endothelium-dependent dysfunction in middle-aged patients with IGT and in patients with a normal glucose tolerance (NGT). An oral glucose tolerance test was performed to determine the NGT and IGT states. Physiological and biochemical analyses were performed. The carotid artery structure and function were investigated with Doppler supersonic diagnostic equipment. The functioning of the vascular endothelium was analyzed with physiological and biochemical indices in the IGT group. The results showed a significant reduction in endothelium-dependent vasodilation, but not in endothelium-independent vasodilation in the IGT group compared with those of the NGT group. It was identified that the intima-media thickness of the carotid artery and expression levels of endothelin-1 were significantly higher, whereas the endothelium-derived factor C-type natriuretic peptide levels were significantly lower in the IGT group compared with those in the NGT group. Notably, significant correlations were identified between endocrinological changes and body composition, including fat and glucose metabolism, in the IGT group. Our data indicate that vascular endothelial functions may be impaired by fat and glucose metabolism and body composition in IGT patients during prediabetes mellitusare.

Effects of exercise intervention on vascular endothelium functions of patients with impaired glucose tolerance during prediabetes mellitus

Endothelial dysfunction (ED) is an early pathophysiological change in patients with impaired glucose tolerance (IGT) during prediabetes mellitus. This study was designed to test the hypothesis that exercise intervention contributes to the reversal of vascular endothelium-dependent dysfunction in middle-aged patients with IGT. Following exercise intervention, significant changes in endothelin (ET)-1, C-type natriuretic peptide (CNP), ΔDia-P, oral glucose tolerance test (OGTT)2h, fasting insulin, homeostasis model of assessment-insulin resistance (HOMA-IR), body fat percentage, waist circumference and waist to hip ratio were measured. However, no marked changes in carotid artery intima-media thickness (IMT), fasting blood glucose and BMI were observed following exercise intervention. Validity analysis of index changes in the two exercise intervention groups further confirmed there was no change. Exercise intervention increased CNP levels, decreased ET-1 levels and increased ΔDia-P, indicating improved vascular endothelium function. Decreased HOMA-IR following exercise suggests enhanced insulin sensitivity. Exercise intervention also improved glucose metabolism via decreased OGTT2h and fasting insulin. In addition, decreased waist circumference, ratio of waist to hip and body fat percentage following exercise intervention improved changes of body composition, including BMI, body fat and waist circumference. These results indicate that exercise intervention may reverse vascular endothelium-dependent dysfunction in middle-aged patients with IGT. This study also provided direct clinical data supporting the use of exercise intervention to prevent diabetes mellitus (DM) during the early stage.

Saw palmetto ethanol extract inhibits adipocyte differentiation

The fruits of saw palmetto have been used for the treatment of a variety of urinary and reproductive system problems. In this study we investigated whether the fruit extracts affect in vitro adipogenesis. Saw palmetto ethanol extract inhibited the lipid droplet accumulation by induction media in a dose-dependent manner, and it also attenuated the protein expressions of C-EBPα and PPARγ. Phosphorylation of Erk1/2 and Akt1 were also decreased by saw palmetto ethanol extract. This report suggests that saw palmetto extracts selectively affect the adipocyte differentiation through the modulation of several key factors that play a critical role during adipogenesis.

Fenugreek extract as an inducer of cellular death via autophagy in human T lymphoma Jurkat cells

Background

Drugs used both in classical chemotherapy and the more recent targeted therapy do not have cancer cell specificity and, hence, cause severe systemic side effects. Tumors also develop resistance to such drugs due to heterogeneity of cell types and clonal selection. Several traditional dietary ingredients from plants, on the other hand, have been shown to act on multiple targets/pathways, and may overcome drug resistance. The dietary agents are safe and readily available. However, application of plant components for cancer treatment/prevention requires better understanding of anticancer functions and elucidation of their mechanisms of action. The current study focuses on the anticancer properties of fenugreek, a herb with proven anti-diabetic, antitumor and immune-stimulating functions.

Method

Jurkat cells were incubated with 30 to 1500 μg/mL concentrations of 50% ethanolic extract of dry fenugreek seeds and were followed for changes in viability (trypan blue assay), morphology (microscopic examination) and autophagic marker LC3 transcript level (RT-PCR).

Results

Incubation of Jurkat cells with fenugreek extract at concentrations ranging from 30 to 1500 μg/mL for up to 3 days resulted in cell death in a dose- and time-dependent manner. Jurkat cell death was preceded by the appearance of multiple large vacuoles, which coincided with transcriptional up-regulation of LC3. GC-MS analysis of fenugreek extract indicated the presence of several compounds with anticancer properties, including gingerol (4.82%), cedrene (2.91%), zingerone (16.5%), vanillin (1.52%) and eugenol (1.25%).

Conclusions

Distinct morphological changes involving appearance of large vacuoles, membrane disintegration and increased expression of LC3 transcripts indicated that fenugreek extract induced autophagy and autophagy-associated death of Jurkat cells. In addition to the already known apoptotic activation, induction of autophagy may be an additional mechanism underlying the anticancer properties of fenugreek. This is the first report showing fenugreek as an inducer of autophagy in human cells and further work is needed to define the various intermediates of the autophagic pathway.

Identification of novel human dipeptidyl peptidase-IV inhibitors of natural origin (Part II): in silico prediction in antidiabetic extracts

BACKGROUND

Natural extracts play an important role in traditional medicines for the treatment of diabetes mellitus and are also an essential resource for new drug discovery. Dipeptidyl peptidase IV (DPP-IV) inhibitors are potential candidates for the treatment of type 2 diabetes mellitus, and the effectiveness of certain antidiabetic extracts of natural origin could be, at least partially, explained by the inhibition of DPP-IV.

METHODOLOGY/PRINCIPAL FINDINGS

Using an initial set of 29,779 natural products that are annotated with their natural source and an experimentally validated virtual screening procedure previously developed in our lab (Guasch et al.; 2012) [1], we have predicted 12 potential DPP-IV inhibitors from 12 different plant extracts that are known to have antidiabetic activity. Seven of these molecules are identical or similar to molecules with described antidiabetic activity (although their role as DPP-IV inhibitors has not been suggested as an explanation for their bioactivity). Therefore, it is plausible that these 12 molecules could be responsible, at least in part, for the antidiabetic activity of these extracts through their inhibitory effect on DPP-IV. In addition, we also identified as potential DPP-IV inhibitors 6 molecules from 6 different plants with no described antidiabetic activity but that share the same genus as plants with known antidiabetic properties. Moreover, none of the 18 molecules that we predicted as DPP-IV inhibitors exhibits chemical similarity with a group of 2,342 known DPP-IV inhibitors.

CONCLUSIONS/SIGNIFICANCE

Our study identified 18 potential DPP-IV inhibitors in 18 different plant extracts (12 of these plants have known antidiabetic properties, whereas, for the remaining 6, antidiabetic activity has been reported for other plant species from the same genus). Moreover, none of the 18 molecules exhibits chemical similarity with a large group of known DPP-IV inhibitors.

Fenugreek attenuation of diabetic nephropathy in alloxan-diabetic rats: attenuation of diabetic nephropathy in rats

Diabetic nephropathy is a major cause of morbidity and mortality in diabetic patients. To prevent the development of this disease and to improve advanced kidney injury, effective therapies directed toward the key molecular target are required. In this paper, the efficacy of fenugreek to restore the kidney function of diabetic rats via its antioxidant and anti-inflammatory activities has been studied. Novel data showing the efficacy of fenugreek to attenuate progression of diabetic nephropathy and production of interleukin-6 (IL-6) in rats compared with a diabetic untreated group were obtained. Rats were classified into five groups; control, diabetic untreated, and three diabetic groups treated with fenugreek, rosiglitazone, and metformin. Treatment with fenugreek has been continued for 12 weeks. Fenugreek was found to significantly reduce the high levels of glucose, urea, creatinine, sodium, potassium, and IL-6 in serum compared with the diabetic untreated group. In addition, levels of malondialdehyde and IL-6 in the kidney homogenate were significantly reduced as a result of the fenugreek treatment compared with the diabetic untreated group. Moreover, concentration of GSH and the activity of both superoxide dismutase and catalase were considerably increased in the diabetic treated groups compared with the diabetic untreated group. Furthermore, glomerular mesangial expansion was reduced in the treated animal groups. These findings suggest a therapeutic potential of fenugreek against diabetic nephropathy, explain its antioxidative/anti-inflammatory properties and provide a direction for future research.