Antihyperglycemic and antihyperlipidemic effects of fruit extract of Hodgsonia heteroclita (Roxb.) Hook. f. & Thomson in diabetic mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Hodgsonia heteroclita has been known as an important traditionally consumed medicinal plant of North-East India known to have antidiabetic properties. This study aims to investigate the effects of the ethanolic fruit extract of Hodgsonia heteroclita against hyperglycemia and hyperlipidemia by using streptozotocin (STZ) treated diabetic mice. MATERIALS AND METHODS: The fruits of H. heteroclita were collected from the various parts of Kokrajhar district, Assam India (Geographic coordinates: 26°24'3.85″ N 90°16'22.30″ E). Basic morphological evaluations were carried out by the Botanical Survey of India, Eastern circle, Shillong, who also certified and identified the plant. Hexane, chloroform, and ethanolic extracts of the fruit of H. heteroclita were investigated for α-amylase inhibition assay as a rapid screening tool for examining anti-diabetic activity. The efficacy of ethanolic extract at a dose of 100, 200, and 300 mg/kg body weight was tested for 21 days in STZ-induced diabetic mice. The body weight, fasting plasma glucose and serum lipids, and hepatic glycogen levels were measured in experimental animals to examine the antihyperglycemic and antihyperlipidemic efficacy of the extract. Both HPTLC and LC-MS analysis was performed to examine the phyotochemicals present in the ethanolic extract of H. heteroclita. RESULTS: It has been observed that treatment with the ethanolic extract dose-dependently reduced the plasma glucose levels, total cholesterol, low density lipoprotein-cholesterol, very low-density lipoprotein-cholesterol, triglyceride, and increased the body weight, liver glycogens and high-density lipoprotein-cholesterol in STZ treated diabetic mice. HPTLC demonstrated the presence of triterpene compounds and LC-MS analysis revealed the presence Cucurbitacin I, Cucurbitacin E, and Kuguacin G as the triterpene phytoconstituents. CONCLUSION: The present study demonstrated that ethanolic fruit extract of H. heteroclita improved both glycemic and lipid parameters in mice model of diabetes.

Anti-diabetic and anti-urease potential of Osbeckia nutans Wall. leaves.

A study was conducted to investigate the anti-diabetic and anti-urease potential of Osbeckia nutans leaves (ONL). Six compounds, i.e. quercetin-3-O-glucoside, myricetin, shikimic acid, catechin, trans-ferulic acid and luteolin were identified from the butanol sub-fraction, BE2 and the ethyl acetate sub-fraction, EA5 of ONL. BE2 inhibited α-glucosidase and Jack bean urease with IC50 values of 0.036 µg/mL (437.46 µg/mL for acarbose) and 0.327 mg/mL (0.039 mg/mL for thiourea), respectively. In the glucose uptake experiment, BE2 (0.05 mg/mL) treatment resulted in a substantial increase in glucose uptake in free fatty acid (FFA)-treated cells at a concentration 10 times lower than that seen in EA5 (0.5 mg/mL) treated cells. The binding energies of quercetin-3-O-glucoside with α-glucosidase, glucose transporter GLUT4 and H. pylori urease were found to be -94.2585, -219.8271 and -254.391 kcal/mol, respectively. This study revealed that ONL has anti-diabetic and anti-urease abilities and further in-depth research may unveil its full potential.

A popular fermented soybean food of Northeast India exerted promising antihyperglycemic potential via stimulating PI3K/AKT/AMPK/GLUT4 signaling pathways and regulating muscle glucose metabolism in type 2 diabetes.

This study examined the antidiabetic efficacy of popular fermented soybean foods (FSF) of Northeast (NE) India. Results showed that among different FSF, aqueous extract of Hawaijar (AEH), a traditional FSF of Manipur, NE India, significantly augmented glucose utilization in cultured myotubes treated with high glucose (HG, 25 mM). Furthermore, AEH also upregulated glucose uptake, glucose-6-phosphate level, and phopho-PI3K/phospho-AKT/phospho-AMPK/GLUT4 protein expression in HG-treated myotubes. In vivo studies demonstrated that AEH supplementation (50, 100, or 200 mg/kg body weight/day, oral gavaging, 16 weeks) reduced body weight, fasting blood glucose, glycated hemoglobin, insulin resistance, and glucose intolerance in rats fed with high-fat diet (HFD). AEH supplementation stimulated phopho-PI3K/phospho-AKT/phospho-AMPK/GLUT4 signaling cascades involved in glucose metabolism of muscle tissues in diabetic rats. Chemical profiling of AEH (SDS-PAGE, immunoblotting, and HRMS) suggests the possible role of bioactive proteins/peptides and isoflavones underlying the antihyperglycemic potential AEH. Results from this study will be helpful for developing food-based prophylactics/therapeutics in managing hyperglycemia. PRACTICAL APPLICATIONS: Fermented soybean foods are gaining acceptance due to multiple health benefits. This study for the first time reports the antidiabetic potential of Hawaijar, an indigenous fermented soybean food of North-East India. Higher abundance of bioactive compounds (isoflavones and proteins/peptides) in Hawaijar may be responsible for the alleviation of impaired glucose metabolism associated with diabetes. The findings may be helpful for the development of a novel therapeutic to achieve better control of hyperglycemia and improve the lives of the patient population with diabetes.

Potentiating the intracellular killing of Staphylococcus aureus by dihydroquinazoline analogues as NorA efflux pump inhibitor.

Staphylococcus aureus is an emerging human pathogen that has become difficult to treat due to its high resistance against wide range of drugs. Emergence of drug resistant isolates has further convoluted the treatment process. Among different resistance mechanisms, efflux pump proteins play a central role and has made itself a direct approach for therapeutic exploration. To demarcate the role of dihydroquinazoline analogues as NorA efflux pump inhibitor in S. aureus1199B (NorA over producing) strain total seventeen analogues were synthesized and tested for their modulatory effects on norfloxacin and Etbr resistance. Further accumulation assays, bacterial time kill kinetics, cytotoxicity assay were also carried out. The intracellular killing ability of analogues, as EPI was determined using THP-1 monocytes. The binding interaction of analogues with NorA was also predicted. Dihydroquinazoline analogues notably reduced the MIC of norfloxacin and Etbr in S. aureus1199B. In addition to their very low toxicity, they showed high Etbr and norfloxacin accumulation respectively. Further effective over time log reduction in bacterial kill kinetics in presence of these analogues confirmed their role as NorA efflux pump inhibitor. FESEM analysis clearly depicted their effect on the cell surface morphology owing to its lyses. The most significant finding of this study was the ability of analogues to significantly reduce the intracellular S. aureus1199B in human THP-1 monocytes in presence of norfloxacin. Our study has shown for the first time the possibility of developing the dihydroquinazoline analogues as NorA efflux pump inhibitors for S. aureus and control its infection.

Gamma-glutamyl-carboxylated Gas6 mediates positive role of vitamin K on lowering hyperglycemia in type 2 diabetes.

The role of gamma-glutamyl-carboxylated growth arrest-specific 6 (cGas6) in mediating the beneficial effect of vitamin K (VK) on regulating glucose metabolism remains elusive. We took a three-pronged approach-evaluating human type 2 diabetes (T2D), high-fat diet (HFD)-fed mice, and in vitro cultured myotubes-to address this. Blood samples were collected from both T2D patients and control subjects; skeletal muscle and blood samples were collected from HFD-fed mice with or without VK supplementation (1, 3, and 5 µg/kg BW, 8 weeks); and the molecular mechanism of cGas6 was dissected using GGCX, Gas6, AXL, or IR siRNA-transfected cultured myotubes. Plasma cGas6 and VK were significantly lower in T2D patients compared with control; and cGas6 and the cGas6/Gas6 ratio were positively correlated with VK and inversely correlated with fasting glucose in T2D patients, suggesting an important role for plasma VK and cGas6 in maintaining glucose homeostasis in T2D. Animal studies revealed that VK supplementation dose-dependently upregulated plasma cGas6; stimulated the protein expression of cGas6, PI3K, pAKT, and GLUT4 in skeletal muscle; and reduced hyperglycemia in HFD-fed T2D mice. And in vitro mRNA knockdown studies demonstrated the requirement of cGas6 in mediating the positive effect of VK on glucose metabolism via stimulating the PI3K/pAKT/GLUT4 signaling pathway in high glucose-treated myotubes. These results demonstrate a significant involvement of cGas6 in mediating the beneficial effect of VK on regulating glucose homeostasis in T2D.

Atmospheric particulate matters in an Indian urban area: Health implications from potentially hazardous elements, cytotoxicity, and genotoxicity studies.

The nature of the atmospheric particulate matters (PMs) varies depending on their sizes and their origin from different activities in the background environment. These PMs are associated with potentially hazardous elements (PHEs) such as organic compounds (e.g. Polyaromatic Hydrocarbons) that can be harmful to health. The main objective of this work is the identification and investigation of the toxicological aspects of PHEs in PMs during pre-monsoon and post-monsoon season in an urban area of Northeast region (NER) of India. In the course of the study, the 24 -hs average concentrations of PMs were detected to be more than two-times higher than the Indian standard limit (NAAQ, category) which indicates poor air quality in both the seasons around the sampling sites. This study demonstrates that the concentrations of PM-bound PAHs are mutagenic and that the Excess Cancer Risks exceed the USEPA standard limits. PMs cause cytotoxicity and can also induce genotoxicity to human health analyzed by cell culture and gel electrophoresis. This study helps to promote research to evaluate the PMs bound PHEs toxicity in diverse human cell lines and also their relationship with climatic factors as well as quantitative source apportionment for mitigation purposes.

Chlorin e6 decorated doxorubicin encapsulated chitosan nanoparticles for photo-controlled cancer drug delivery.

In the study we have reported the physico-chemical, photophysical and morphological properties of chlorin e6 (Ce6) decorated doxorubicin (DOX) encapsulated chitosan (CS)-tripolyphosphate (TPP) nanoparticles which prepared by ionotropic gelation method. The Ce6 physically loaded onto the nanoparticles by self-assembly of CS with TPP-DOX under aqueous conditions. The results from DLS studies highlights the prepared nanoparticles that possess the size in the range of 80-120 nm. with negatively charged of -6 mV. The SEM and AFM images showed 80-120 nm size while the average size of the Ce6 decorated nanoparticles was found to be around 100-130 nm. The absorption spectra of Ce6 decorated nanoparticles are similar when compared to free Ce6 which suggest there is no change in the Ce6 chromophore upon decoration. This nanoparticle showed high photostability and singlet oxygen generation (SOG). The Ce6 decorated and DOX encapsulated nanoparticles sizes and charges are in the range of 90-130 nm and -30 mV respectively. The nanoparticles showed high encapsulation efficiency towards DOX as well as pH controlled release. This has significant anti-proliferative activity against MCF-7 breast cancer cells after irradiation at near infra-red (NIR) ranges were evaluated. This could have potential applications in photo-controlled smart DOX delivery system for cancer treatment.

Environmental and toxicological assessment of nanodiamond-like materials derived from carbonaceous aerosols.

Carbonaceous aerosols (CAs) are ubiquitous and among the most significant environmental materials found in ambient air, mainly derived from anthropogenic sources (biomass burning, industrial activity, vehicle emissions, etc.). Elemental carbon (black carbon) and organic carbons are the major constituents of CAs. Due to their toxic effects, they are considered as high-risk compounds for human health. The key objective of the present work is to conduct a feasibility study for the conversion of CAs (TSP and PM10) into a value-added carbon nanostructured product by using a chemical method. High resolution-transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier transforms infrared spectroscopy (FT-IR), X-ray photoelectron spectrometer (XPS), ultraviolet-visible spectroscopy (UV-visible), fluorescence spectroscopy (FL), and Zeta potential analyses indicated the formation of carbon nanomaterials with crystalline phases, which exhibit the characteristics of nanodiamonds (NDs). The HR-TEM image analysis showed that the nominal size of the CAs-derived NDs ranged from 4 to 17 nm composed of mainly carbon and oxygen. The FT-IR and XPS analysis indicated that the NDs are highly functionalized with an oxygen-containing functional group. The CAs-derived NDs showed the property of blue-fluorescence with excitation dependent. In the cytotoxicity and genotoxicity study, the NDs obtained was observed to be biocompatible and suitable for bioimaging applications. This result provides a new avenue for the conversion of CAs to high-value products leading to the mitigation of atmospheric pollution.

Hexane-Isopropanolic Extract of Tungrymbai, a North-East Indian fermented soybean food prevents hepatic steatosis via regulating AMPK-mediated SREBP/FAS/ACC/HMGCR and PPARα/CPT1A/UCP2 pathways.

This study for the first time examined the prophylactic role of Tungrymbai, a well-known fermented soybean food of North-East India, against hepatic steatosis. Treatment with hexane-isopropanolic (2:1, HIET) but not hydro-alcoholic (70% ethanol, HAET) extract dose-dependently (0.1, 0.2, or 0.3 µg/mL) reduced the intracellular lipid accumulation as shown by lower triglyceride levels and both Oil Red O and Nile Red staining in palmitate (PA, 0.75 mM)-treated hepatocytes. Immunobloting, mRNA expression, and knock-down studies demonstrated the role of AMPK-mediated SREBP/FAS/ACC/HMGCR and PPARα/CPT1A/UCP2 signaling pathways in facilitating the beneficial role of HIET against lipid accumulation in PA-treated hepatocytes. Animal studies further showed a positive effect of HIET (20 µg/kg BW, 8 weeks, daily) in regulating AMPK/SREBP/PPARα signaling pathways and reducing body weight gain, plasma lipid levels, and hepatic steatosis in high fat diet (HFD)-fed mice. Histological analyses also revealed the beneficial effect of HIET in reducing hepatic fat accumulation in HFD mice. Chemical profiling (HRMS, IR, and HPLC) demonstrated the presence of menaquinone-7 (vitamin K2) as one of the bio-active principle(s) in HIET. Combining all, this study demonstrates the positive effect of HIET on reducing hepatic steatosis via regulating AMPK/SREBP/PPARα signaling pathway.

Molecular mechanism of diabetic neuropathy and its pharmacotherapeutic targets.

Diabetic neuropathy is regarded as one of the most debilitating outcomes of diabetes mellitus and may cause pain, decreased motility, and even amputation. Diabetic neuropathy includes multiple forms, ranging from discomfort to death. Prognosis of diabetic neuropathy is an uphill task as it remains silent for several years after the onset of diabetes. Hyperglycemia, apart from inducing oxidative stress in neurons, also leads to activation of multiple biochemical pathways which constitute the major source of damage and are potential therapeutic targets in diabetic neuropathy. A vast array of molecular pathways, including polyol pathway, hexosamine pathway, PKCs signaling, oxidative stress, AGEs pathway, PARP pathway, MAPK pathway, NF-κB signaling, hedgehog pathways, TNF-α signaling, cyclooxygenase pathway, interleukins, lipoxygenase pathway, nerve growth factor, Wnt pathway, autophagy, and GSK3 signaling may be accounted for the pathogenesis and progression of diabetic neuropathy. Although symptomatic treatment is available for diabetic neuropathy, few treatment options are available to eliminate the root cause. The immense physical, psychological, and economic burden of diabetic neuropathy highlights the need for cost effective and targeted therapies. The main aim of this review is to highlight the putative role of various mechanisms and pathways involved in the development of diabetic neuropathy and to impart an in-depth insight on new therapeutic approaches aimed at delaying or reversing various modalities of diabetic neuropathy.

Implication of a novel vitamin K dependent protein, GRP/Ucma in the pathophysiological conditions associated with vascular and soft tissue calcification, osteoarthritis, inflammation, and carcinoma.

Gla-rich protein (GRP) or unique cartilage matrix-associated protein (Ucma), the newest member of vitamin K dependent proteins, carries exceptionally high number of γ-carboxyglutamic acid (Gla) residues which contributes to its outstanding capacity of binding with calcium in the extracellular environment indicating its potential role as a global calcium modulator. Recent studies demonstrated a critical function of GRP in the regulation of different pathophysiological conditions associated with vascular and soft tissue calcification including cardiovascular diseases, osteoarthritis, inflammation, and skin and breast carcinomas. These findings established an important relationship between γ-carboxylation of GRP and calcification associated disease pathology suggesting a critical role of vitamin K in the pathophysiological features of various health disorders. This review for the first time summarizes all of the updated findings related to the functional activities of GRP in the pathogenesis of several diseases associated with vascular and soft tissue mineralization, osteoarthritis, inflammation, and carcinoma. The outcome of this review will improve the understanding about the role of GRP in the pathogenesis of tissue calcification and its associated health disorders, which should in turn lead to the design of clinical interventions to improve the condition of patients associated with these health disorders.

Vitamin K1 inversely correlates with glycemia and insulin resistance in patients with type 2 diabetes (T2D) and positively regulates SIRT1/AMPK pathway of glucose metabolism in liver of T2D mice and hepatocytes cultured in high glucose.

There is no previous study in the literature that has examined the relationship between circulating vitamin K1 (VK1) with glycemic status in type 2 diabetes (T2D). Moreover, scientific explanation for the beneficial role of VK1 supplementation in lowering glycemia in diabetes is yet to be determined. This study for the first time demonstrated that circulating VK1 was significantly lower in T2D patients compared to age-matched control subjects, and VK1 levels in T2D were significantly and inversely associated with fasting glucose and insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR)], which suggest that boosting plasma VK1 may reduce the fasting glucose and insulin resistance in T2D patients. Using high-fat-diet-fed T2D animal model, this study further investigated the positive effect of VK1 supplementation on glucose metabolism and examined the underlying molecular mechanism. Results showed that VK1 supplementation [1, 3, 5 µg/kg body weight (BW), 8 weeks] dose dependently improved the glucose tolerance; decreased BW gain, fasting glucose and insulin, glycated hemoglobin, HOMA-IR and cytokine secretion (monocyte chemoattractant protein-1 and interleukin-6); and regulated the signaling pathway of hepatic glucose metabolism [sirtuin 1 (SIRT1)/AMP-activated protein kinase (AMPK)/phosphoinositide 3-kinase/phosphatase and tensin homolog/glucose transporter 2/glucokinase/glucose 6 phosphatase], lipid oxidation (peroxisome proliferator-activated receptor alpha/carnitine palmitoyltransferase 1A) and inflammation (nuclear factor kappa B) in T2D mice. Comparative signal silencing studies also depicted the role of SIRT1/AMPK in mediating the effect of VK1 on glucose metabolism, lipid oxidation and inflammation in high-glucose-treated cultured hepatocytes. In conclusion, this study demonstrates that circulating VK1 has a positive effect on lowering fasting glucose and insulin resistance in T2D via regulating SIRT1/AMPK signaling pathway.

Prophylactic role of vitamin K supplementation on vascular inflammation in type 2 diabetes by regulating the NF-κB/Nrf2 pathway via activating Gla proteins.

There is no previous study that has examined the relationship between circulating vitamin K1 (VK1) and vascular inflammation in type 2 diabetes (T2D). This study aims to examine the hypothesis that circulating VK1 deficiency may be associated with higher inflammation and insulin resistance in T2D patients and that VK1 supplementation regulates the NF-κB/Nrf2 pathway via activating VK-dependent Gla proteins and reduces vascular inflammation. The results showed that plasma VK1 levels were significantly lower and MCP-1, fasting glucose, HbA1c, and insulin resistance (HOMA-IR) were significantly higher in T2D patients compared to those in the controls. The lower levels of VK1 in T2D patients were significantly and inversely correlated with MCP-1 and HOMA-IR, which suggests that VK1 supplementation may reduce the vascular inflammation and insulin resistance in T2D. Using a high fat diet-fed T2D mice model this study further demonstrated that VK1 supplementation (1, 3, 5 µg per kg BW, 8 weeks) dose-dependently decreased the body weight gain, glucose intolerance, fasting glucose, glycated hemoglobin, HOMA-IR, and cytokine secretion (MCP-1 and IL-6) in T2D mice. Further cell culture studies showed that VK1 supplementation (1, 5, or 10 nM) decreased NF-κB phosphorylation and MCP-1 secretion and increased Nrf2 protein expression in high glucose (HG, 25 mM)-treated monocytes. Signal silencing studies with GGCX siRNA again depicted the role of VK-dependent Gla proteins in mediating the effect of VK1 on vascular inflammation in HG-treated cells. In conclusion, this study suggests that circulating VK1 has a positive effect in lowering vascular inflammation in T2D by regulating NF-κB/Nrf2 transcription factors via activating VK-dependent Gla proteins.

Antioxidant and glucose metabolizing potential of edible insect, Brachytrupes orientalis via modulating Nrf2/AMPK/GLUT4 signaling pathway.

Brachytrupes orientalis (Gryllidae) is a common edible insect species eaten by the different tribes of North East India. This study investigated the potentiality of Brachytrupes orientalis extracts in different solvent hydro-alcoholic (AEBO), hexane (HEBO) and ethyl acetate (EEBO) on glucose utilization and cell viability in high glucose (HG) treated myotubes. It has been observed that AEBO supplementation significantly increased the glucose utilization against HG exposure; however, treatment HEBO and EEBO have no significant effect. AEBO also increased the intercellular glucose-6-phosphate level and the protein expression of both phospho-AMPK and GLUT4 in HG treated myotubes in a dose dependent manner. Furthermore, supplementation with AEBO decreased the intercellular ROS production, lipid peroxidation, and up-regulated the protein expression of Nrf2 and GST. Chromatography and Spectroscopic analyses of AEBO also suggest that Ursolic acid may be one of the bioactive principles with rich potassium, sodium, calcium and magnesium content.

Implication of a novel Gla-containing protein, Gas6 in the pathogenesis of insulin resistance, impaired glucose homeostasis, and inflammation: A review.

Growth arrest specific 6 (Gas6), a vitamin K-dependent protein plays a significant role in the regulation of cellular homeostasis via binding with TAM-receptor tyrosine kinases. Several studies reported the role of Gas6 in cancer, glomerular injury, obesity, and inflammation, however, very little is known about its role in insulin resistance (IR) and impaired glucose metabolism. Majority of the studies reported an inverse correlation of Gas6 protein levels or gene polymorphism with plasma glucose, HbA1c, IR, and inflammatory cytokines among type 2 diabetes (T2D) and obese subjects. However, few studies reported a positive correlation of Gas6 protein levels or gene polymorphism with IR and inflammation among obese subjects. This review for the first time provides an overview of the association of Gas6 protein levels or gene polymorphism with IR, glucose intolerance, and inflammation among T2D and obese subjects. This review also depicts the probable mechanism underlying the association of Gas6 with glucose intolerance and inflammation. The outcome of this review will increase the understanding about the role of Gas6 in the pathogenesis of IR, glucose intolerance and inflammation and that should in turn lead to the design of clinical interventions to improve glucose metabolism and the lives of the T2D patients.