Abietic acid attenuates hyperglycemia and oxidative stress via TLR4-mediated inflammation and PPAR-γ-Nrf2 activation: evidence from network pharmacology and in vivo validation.

Abstract

To reconnoitre the mechanism of Abietic acid (AA) in diabetes by in-silico and in-vivo experiments. Using GeneCards, diabetes gene targets were obtained. The protein-protein interaction and network topology analysis were performed using the String platform and Cytoscape 3.7.2. The enrichment analysis was done by Shiny GO. The docking was by Autodeck. Diabetes was induced by injecting STZ (55 mg/kg, i.p once) in Sprague-Dawley rats. The parameters included glucose, lipids, blood pressure, ECG, OGTT, kidney and cardiac markers, liver enzymes, AMPK, Nrf2, PPAR-γ, TLR-4, oxidative markers, LVF tests, and histopathology. AA interacts with 15 important targets (PIK3CD, MAPK1, NF-κB, mTOR, STAT3, GRIN1, ITGB3, ACACA, HSP90AB1, SERPINE1, ADRB1, ULK1, TLR4, CTSD, CDK5). The signalling pathways, like insulin, MAPK1, TLR, AMPK, JAK-STAT, are associated with these proteins. In docking, the highest affinity of AA was observed for ITGB3 (- 8.1), TLR4 (- 7.8), and ACACA (- 7.3). In rats, AA(40 and 80 mg/kg) decrease hyperglycaemia and hyperinsulinemia, improves glucose tolerance, normalize blood pressure, combat dyslipidaemia (decrease triglyceride, total cholesterol, LDL, increase HDL), preserves myocytes and ventricular function (decrease troponin-I, LDH, CK-MB, LVEDP, normal ECG), hepatoprotective (decrease AST, ALT), reno-protective (decrease creatinine, urea, uric acid) and combat oxidative stress (decrease MDA, increase SOD, catalase). Nrf2, AMPK, and PPAR γ levels were increased while TLR-4 levels were decreased after AA treatment. The study is supported by the preserved histopathological architecture of pancreatic, renal, hepatic, and cardiac cells. The present study preliminarily clarifies that AA exhibits therapeutic potential in preclinical models through multitargets and multi-pathways (Nrf/TLR4/PPAR γ), which points out a new direction for further research and clinical application.