Ameliorative effect of montelukast against STZ induced diabetic nephropathy: targeting HMGB1, TLR4, NF-κB, NLRP3 inflammasome, and autophagy pathways

Abstract

AbstractDiabetic nephropathy (DN) is reported as one of the most serious microvascular diabetic complications and the trigger of end-stage renal disease (ESRD), underscoring the concern of any therapeutic intervention directed at ameliorating the development and progression of DN. The current study explored the renoprotective impact of montelukast (Mon) against streptozotocin (STZ)-induced DN in rats compared to a standard anti-hyperglycemic insulin (Ins) treatment. Diabetes was induced by a single dose of STZ (55 mg/kg). Diabetic rats were treated with Mon (10 and 20 mg/kg, oral gavage) for eight weeks. Mon administration for 8 weeks after induction of diabetes conferred significant dose-dependent renoprotection, independent of blood glucose levels (unlike Ins), as evidenced by the improvement in serum creatinine, and blood urea nitrogen (BUN), and ameliorated STZ-induced renal necrotic, inflammatory alterations, and renal fibrosis. Additionally, Mon treatment in diabetic rats significantly restored redox hemostasis as evidenced by malondialdehyde (MDA) and total antioxidant capacity (TAC) levels; significantly reduced the renal expression of high mobility group box (HMGB) 1, toll-like receptor (TLR) 4, nuclear factor kappa B (NF-κB) (in the nucleus), NOD-like receptor family pyrin domain containing (NLRP) 3, and interleukin (IL)-1β. Moreover, Mon administration ameliorated the dysregulation in autophagy as evidenced by p62 and microtubule-associated protein 1A/1B-light chain 3 (LC3)-II levels. In conclusion, the renoprotective effect of Mon is potentially associated with its modulatory effect on inflammatory cytokines, antioxidant properties, and autophagy. Graphical Abstract Renoprotective effect of montelukast and its underlying pathway: Hyperglycemia and advanced glycation end products (AGEs) stimulate the release of high mobility group box (HMGB) 1 from necrotic and inflammatory cells. HMGB1 is considered as one of the endogenous ligands of toll-like receptor (TLR) 4, and the interaction of HMGB1 with TLR4 results in a subsequent translocation of nuclear factor kappa B (NF-κB) from the cytoplasm into the nucleus inducing an inflammatory response. NF-κB is a key mediator of the priming signal responsible for the activation of NOD-like receptor family pyrin domain containing (NLRP) 3 inflammasome by stimulating the expression of both NLRP3 and pro- interleukin (IL)-1β, which is then converted to IL-1β by to mediate inflammation. NLRP3 can induce reactive oxygen species production, while autophagy inhibits AGEs and NLRP3 accumulation. Montelukast show an inhibitory effect on HMGB1, TLR4, NF-κB, NLRP3, and IL-1β and has autophagy stimulating characteristics indicating its potential renoprotective effect.