Thunbergia’s Flowers Secondary Metabolites a Natural Armor Against Kidney Damage by Diclofenac

Nephrotoxicity is a common side effect arising from exposure to drugs or toxins. The study investigates the therapeutic effects of Thunbergia alata and Thunbergia erecta flowers on diclofenac-induced renal injury. Secondary metabolite characterization by positive mode high-resolution-ESI (LC-HR-ESI-MS) was followed by assessing their renal protection against diclofenac-induced damage and molecular docking studies. Using positive LC-HR-ESI-MS, 18 compounds from T. erecta and T. alata were identified. Diclofenac administration induced significant deterioration of all parameters in the kidney in addition to renal tissue contents of several inflammatory markers. The flower extracts of T. alata and T. erecta showed a clear improvement in the treated groups compared to the diclofenac-control group. The results were confirmed by histopathological examinations followed by immunohistochemical determination of vascular endothelial growth factor (VEGF), nuclear factor erythroid 2-related factor 2 (Nrf2), and transforming growth factor beta 1 (TGF-β1) expression. Furthermore, a protein–protein network to understand the complex interplay between the target proteins and their counterparts was done in addition to a molecular docking study of the de-replicated compounds in the active sites of NF-κB, TGF-β1, and VEGFR.