Withaferin A ameliorates renal injury due to its potent effect on inflammatory signaling

Chronic kidney disease (CKD) is one of the major global health concerns and is responsible for end-stage renal disease (ESRD) complications. Inflammation plays a pivotal role in the progression of CKD. In the present study, we evaluated the renoprotective effects of a potent immunomodulator steroidal lactone, Withaferin A (WfA), in an animal model of renal injury (unilateral ureteral obstruction, UUO) and further investigated if the inhibition of inflammatory signaling can be a useful approach to reduce renal injury. Animals were randomly divided into five groups: Sham control, UUO control, WfA control, WfA low dose (1 mg/kg), and WfA high dose (3 mg/kg). Oxidative stress was measured by the estimation of reduced glutathione and lipid peroxidation levels. H&E and Picrosirius Red staining were performed to assess the extent of histological damage and collagen deposition. Furthermore, the molecular mechanism of the WfA effects was explored by immunohistochemistry, enzyme-linked immunosorbent assay, multiplex analysis of transforming growth factor β (TGF-β) pathway, and an array of inflammatory cytokines/chemokines. Interestingly, our pharmacological intervention significantly attenuated tissue collagen, inflammatory signaling, and macrophage signaling. WfA intervention abrogated the inflammatory signaling as evident from the modulated levels of chemokines and cytokines. The levels of TGF-β along with downstream signaling molecules were also attenuated by WfA treatment as revealed by inhibition in the expression of TGF-β1, TGF-β2, p-Smad2, p-Smad3, total Smad4, p-Akt, and p-ERK. We, to the best of our knowledge, prove for the first time that WfA has potential renoprotective activity against UUO-induced nephropathy due to its outstanding anti-inflammatory properties.