An insight into the mechanistic role of (-)-Ampelopsin F from Vatica chinensis L. in inducing insulin secretion in pancreatic beta cells

Resveratrol oligomers, ranging from dimers to octamers, are formed through regioselective synthesis involving the phenoxy radical coupling of resveratrol building blocks, exhibiting remarkable therapeutic potential, including antidiabetic properties. In this study, we elucidate the mechanistic insights into the insulin secretion potential of a resveratrol dimer, (-)-Ampelopsin F (AmF), isolated from the acetone extract of Vatica chinensis L. stem bark in Pancreatic Beta-TC-6 cell lines. The AmF (50 µM) treated cells exhibited a 3.5-fold increase in insulin secretion potential as compared to unstimulated cells, which was achieved through the enhancement of mitochondrial membrane hyperpolarization, elevation of intracellular calcium concentration, and upregulation of GLUT2 and glucokinase expression in pancreatic Beta-TC-6 cell lines. Furthermore, AmF effectively inhibited the activity of DPP4, showcasing a 2.5-fold decrease compared to the control and a significant 6.5-fold reduction compared to the positive control. These findings emphasize AmF as a potential lead for the management of diabetes mellitus and point to its possible application in the next therapeutic initiatives.

Phytochemical Screening and Bioactivity Studies of Endophytes Cladosporium sp. Isolated from the Endangered Plant Vateria Indica Using In Silico and In Vitro Analysis

Vateria indica is persistent tree used in Unani sources for the medication and classified as critically endangered. Thus, endophytes for alternative methods to explore these endangered Plants having rich source pharmaceuticals' active molecules for drug development and production. Endophytes comprises unexplored microbes as a potential source of rich pharmaceutically bioactive compounds attributable to their relationship with the host. In the current study, we have isolated endophyte fungi Cladosporium from the plant Vateria indica and performed phytochemical screening of its ethanolic extract to detect the phytochemicals using thin layer chromatography (TLC), gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography (HPLC), UV-visible spectrophotometry (UV-VIS), and Fourier transform infrared spectroscopy (FTIR). GC-MS analysis revealed the presence of an anticancer compound hydroxymethyl colchicine, antioxidant compound benzoic acid, and antimicrobial 2-(4-chlorophenoxy)-5-nitro in endophyte fungal extract of plant Vateria indica. Moreover, in silico analysis of bioactive compounds identified by GC-MS analysis using the Autodock Vina and SwissADME confirmed excellent anticancer activity methanone, [4-amino-2-[(phenylmethyl) amino]-5-thiazolyl] (4-fluorophenyl)- and hydroxymethyl colchicine against 6VO4 (Bfl-1 protein) as per Lipinski rule. Furthermore, we also demonstrated the excellent antioxidant of endophytic extract compared to plant extract by DPPH and ABTS assay, as well as antimicrobial activity against both Gram (+ ve) and Gram (- ve) bacteria. Moreover, the endophytic extract also showed its antimitotic activity with a mitotic index of 65.32, greater than the plant extract of 32.56 at 10 mg/ml. Thus endophytic fungi Cladosporium species isolated from plant Vateria indica might be used as a potential source for phytochemical anticancer hydroxymethyl colchicine, an antioxidant benzoic acid, and antimicrobial 2-(4-chlorophenoxy)-5-nitro.

Unravelling the human triple negative breast cancer suppressive activity of biocompatible zinc oxide nanostructures influenced by Vateria indica (L.) fruit phytochemicals

The present study delineates the biosynthesis of ZnOVI nanostructures by using aqueous fruit extract of V. indica. The study has disclosed the role of V. indica fruit extract as both reducing and capping agents, ushering the formation of ZnOVI nanostructures with distinct morphologies. The formation of ZnOVI nanostructures was corroborated by FT-IR and UV-visible spectroscopy which was further substantiated by the elemental composition study through EDS spectroscopy. The nanostructures were also investigated by Rietveld refinement of PXRD data, FE-SEM, and BET analysis. The morphology, size, and surface area were found to be precursor stoichiometry dependent. The in-vitro cytotoxicity study of ZnOVI nanostructures carried out on MDA-MB468 human triple-negative breast cancer (TNBC) cells has revealed their potential cytotoxicity (91.18 ± 1.98). MTT assay performed on the NIH3T3 mouse fibroblast cells has unfolded the non-toxic nature of ZnOVI nanostructures. Additionally, the results of the AO-EB dual staining assay indicated early apoptosis in TNBC cells by displaying greenish yellow-fluorescence in the nuclei. Reactive oxygen species (ROS) measurement study has confirmed the elevated intracellular levels of ROS, supporting the oxidative-stress induced cytotoxicity in ZnOVI nanostructures treated TNBC cells. Furthermore, the haemocompatibility of ZnOVI nanostructures was evaluated using human erythrocytes. Thus, the obtained results have shown greater potential in the anticancer activity of bio-fabricated ZnOVI nanostructures.

Isolation and characterization of resveratrol oligomers from the stem bark of Hopea ponga (Dennst.) Mabb. And their antidiabetic effect by modulation of digestive enzymes, protein glycation and glucose uptake in L6 myocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Hopea ponga (Dennst.) Mabb. Is used in traditional herbal formulations for diabetes complications. The aim of this study is to evaluate the antidiabetic effect of extracts and compounds from H. ponga.

MATERIALS AND METHODS

Silica gel column chromatography was performed to identify various chemical components of the plant extract. Different extracts of H. ponga and isolated compounds were screened for their antidiabetic effect by modulation of digestive enzymes and protein glycation. The effect of glucose uptake by the compounds and the pathways through which the compounds mediate the glucose uptake potential were confirmed by fluorescent microscopy, flow cytometry and western blot analysis.

RESULTS

Acetone and ethanol extracts of the stem bark of Hopea ponga (Dennst.) Mabb. Afforded six resveratrol oligomers namely, E-resveratrol (1), (-)-ε-viniferin (2), (-)-α-viniferin (3), trihydroxyphenanthrene glucoside (THPG) (4), vaticaphenol A (5), (-)-hopeaphenol (6), along with four phytosterols. The structures were determined on the basis of spectroscopic analyses including nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HRMS) data. Compounds 1-5 and 7-10 were tested for their α-glucosidase, α-amylase and glycation inhibitiory activities. All the resveratrol oligomers (1-5) showed prominent α-glucosidase inhibition with IC₅₀ values, 12.56 ± 1.00, 23.98 ± 1.11, 7.17 ± 1.10, 31.74 ± 0.42 and 16.95 ± 0.39 μM, respectively. Molecular docking studies also supported the observed α-glucosidase inhibition. Compound 3 displayed IC₅₀ values of 4.85 ± 0.06 and 27.10 ± 0.04 μM in α-amylase and glycation inhibitory assays activity. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay revealed that the compounds 3 and 4 were found to be less toxic at a concentration of 100 μM (<10%) and 25 μM (<20%), respectively. The effect of glucose uptake performed by 2-(N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (2-NBDG) in L6 myoblast were measured by fluorescent microscopy and flow cytometry. The compounds 3 and 4 showed 2-NBDG uptake of 49.6% and 38.8% respectively. By examining the molecular pathway through which the compounds elicit their glucose uptake potential, it was observed that both the compounds mainly act via AMPK pathway.

CONCLUSION

This is the first report on the isolation of compounds from H. ponga. Altogether, the results of this study reveal the antidiabetic effects of H. ponga extracts and isolated compounds promoting traditional use of this plant in the treatment of diabetes.

Synthesis and in vitro evaluation of zerumbone pendant derivatives: potent candidates for anti-diabetic and anti-proliferative activities

A series of zerumbone pendant derivatives were synthesized and evaluated for their α-glucosidase, α-amylase and glycation inhibition activities.