Neuroprotective Properties of Wild Medicinal Mushroom, Sanguinoderma rugosum (Agaricomycetes), Extracts against Glutamate-Induced Hippocampal Cells.

Neurological diseases are increasingly recognized as a health burden worldwide, mainly affecting the elderly population. Sanguinoderma rugosum (=Amauroderma rugosum) is a wild medicinal mushroom traditionally used to alleviate inflammation and prevent seizures. The present study aimed to investigate the neuroprotective and neurorescue effects as well as the possible mechanisms of S. rugosum extracts on glutamate-induced HT-22 mouse hippocampal neuronal cells. The mycelia of S. rugosum were subjected to submerged liquid fermentation followed by solvent extraction and fractionation. The neurotoxicity, neuroprotective, and neurorescue activities of S. rugosum extracts were assessed via the MTT viability assay at 24 and 48 h. The effects of S. rugosum extracts on glutamate-induced oxidative stress and cell death were investigated through flow cytometry. Gas chromatography/mass spectrometry (GC/MS) analysis was conducted to identify the bioactive compounds in the S. rugosum hexane fraction (SR-HF). All extracts were noncytotoxic toward HT-22 cells. Pretreatment with S. rugosum ethanolic extract (SR-EE; 12.5 µg/mL) or SR-HF (100 µg/mL) markedly (P < 0.05) improved the loss of cell viability and attenuated the accumulation of reactive oxygen species production. Pretreatment with SR-HF was also demonstrated to inhibit glutamate-induced cell death. The MTT assay showed that all extracts generally rescued glutamate-induced HT-22 cells at 24 and 48 h. The GC/MS analysis revealed the existence of 11 bioactive components in SR-HF, with linoleic acid, ergosterol, and ethyl linoleate being the main chemical constituents. The current findings suggest that SR-HF could be used as a potential therapeutic intervention to ameliorate oxidative stress and neuroinflammation.

Molecular interaction study of an anticancer drug, ponatinib with human serum albumin using spectroscopic and molecular docking methods.

Binding of a potent anticancer agent, ponatinib (PTB) to human serum albumin (HSA), main ligand transporter in blood plasma was analyzed with several spectral techniques such as fluorescence, absorption and circular dichroism along with molecular docking studies. Decrease in the KSV value with increasing temperature pointed towards PTB-induced quenching as the static quenching, thus affirming complexation between PTB and HSA. An intermediate binding affinity was found to stabilize the PTB-HSA complex, as suggested by the Ka value. Thermodynamic analysis of the binding phenomenon revealed participation of hydrophobic and van der Waals interactions along with hydrogen bonds, which was also supported by molecular docking analysis. Changes in both secondary and tertiary structures as well as in the microenvironment around Trp and Tyr residues of HSA were anticipated upon PTB binding to the protein, as manifested from circular dichroism and three-dimensional fluorescence spectra, respectively. Binding of PTB to HSA led to protein's thermal stabilization. Competitive ligand displacement experiments using different site markers such as warfarin, indomethacin and ketoprofen disclosed the binding site of PTB as Sudlow's site I in HSA, which was further confirmed by molecular docking analysis.