Untargeted metabolomics reveals alterations in metabolites of lipid metabolism and immune pathways in the serum of rats after long-term oral administration of Amalaki rasayana.

Amalaki rasayana, a traditional preparation, is widely used by Ayurvedic physicians for the treatment of inflammatory conditions, cardiovascular diseases, and cancer. Metabolic alterations induced by Amalaki rasayana intervention are unknown. We investigated the modulations in serum metabolomic profiles in Wistar rats following long-term oral administration of Amalaki rasayana. Global metabolic profiling was performed of the serum of rats administered with either Amalaki rasayana (AR) or ghee + honey (GH) for 18 months and control animals which were left untreated. Amalaki rasayana components were confirmed from AR extract using HR-LCMS analysis. Significant reductions in prostaglandin J2, 11-dehydrothromboxane B2, and higher levels of reduced glutathione and glycitein metabolites were observed in the serum of AR administered rats compared to the control groups. Eleven different metabolites classified as phospholipids, glycerophospholipids, glucoside derivatives, organic acids, and glycosphingolipid were exclusively observed in the AR administered rats. Pathway analysis suggests that altered metabolites in AR administered rats are those associated with different biochemical pathways of arachidonic acid metabolism, fatty acid metabolism, leukotriene metabolism, G-protein mediated events, phospholipid metabolism, and the immune system. Targeted metabolomics confirmed the presence of gallic acid, ellagic acid, and arachidonic acid components in the AR extract. The known activities of these components can be correlated with the altered metabolic profile following long-term AR administration. AR also activates IGF1R-Akt-Foxo3 signaling axis in heart tissues of rats administered with AR. Our study identifies AR components that induce alterations in lipid metabolism and immune pathways in animals which consume AR for an extended period.

Protection of mouse brain from paracetamol-induced stress by Centella asiatica methanol extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Centella asiatica (CA) is a medicinal herb traditionally used as a brain tonic in Ayurvedic medicine. Various ethnomedical leads revealed the effective use of CA in the treatment of symptoms associated to oxidative stress and inflammation. AIM OF THE STUDY: The aim of this study was to evaluate the therapeutic ability of CA methanol extract (CAM) in protecting mouse brain and astrocytes from oxidative stress and inflammation induced by Paracetamol, and thus to substantiate the allied traditional/ethnomedical claims of CA. MATERIALS AND METHODS: Chemical profiling of CAM and quantification of its major constituents were carried out by HPTLC-densitometry. Mice were administered with CAM and Paracetamol in various combinations, and oxidative stress parameters (lipid peroxidation, radical scavenging) as well as nitric oxide stress were estimated from isolated mouse brain. Cellular toxicity was investigated by apoptosis/necrosis in primary astrocytes isolated from brain tissues of mouse (which was challenged by CAM/Paracetamol) by flow cytometry and fluorescent microscopy. Expression of inflammatory cytokine mediators (monocyte chemo attractant protein 1, interleukin 1, interferon γ, tumor necrosis factor ß, interleukin 10 and mitogen activated protein kinase 14 gene) in CAM/Paracetamol administered mouse brain tissues was analyzed by real time PCR. Mouse brain tissues challenged by CAM/Paracetamol were also assessed for gross and histopathology. In addition, staining with acridine orange was carried out in C6 cell lines treated with CAM, and viewed under fluorescent microscopy. RESULTS: Paracetamol elicited reactive oxygen species generation was revealed through Ferric Reducing Antioxidant Power (FRAP) activity. CAM reversed the Paracetamol induced free radical and reactive nitrogen species production and increased the scavenging activity which was more pronounced at the higher dose (80 mg/kg b.wt). CAM negated the Paracetamol-induced damage by inhibiting expression of pro-inflammatory cytokines (MCP 1, IL 1, TNF ß), and increasing the expression of the anti-inflammatory cytokine (IL 10) profoundly. Interestingly, MAPK 14 gene expression was decreased gradually and became same as normal control with increase in the dose of CAM. Also, it was evident that CAM protected mouse primary astrocytes from Paracetamol by maintaining a normal morphology. Similarly, apoptosis of primary astrocytes (treated with Paracetamol/CAM) decreased with the increase in CAM dose (80 mg/kg b.wt.) which was evident from flow cytometric data. Severe brain damage in the form of lesions was apparent from the histology of Paracetamol alone treated mouse brain. Whereas, CAM treated together with Paracetamol upturned these lesions. Surprisingly, CAM alone proved to be cytotoxic to C6 Glioma cells. CONCLUSIONS: CAM showed antioxidant and anti-inflammatory effects (which were pronounced at higher doses) against Paracetamol-induced oxidative stress and associated inflammation in mouse brain. The underlying mechanisms may be mediated by inhibiting the pro-inflammatory cytokines TNF ß, IL 1 and MCP 1 via regulation of the antioxidant mediated INF γ and MAPK 14 gene signalling pathways. The major bioactive constituents in CAM are the triterpenoid saponins, asiaticoside and madecassoside. The present results provide pharmacological evidence that CAM acts as an antioxidant and anti-inflammatory agent. Furthermore, this study validates the use of CA as an antioxidant and anti-inflammatory agent in ethnomedicine.