The Role of NF-κB and Bax/Bcl-2/Caspase-3 Signaling Pathways in the Protective Effects of Sacubitril/Valsartan (Entresto) against HFD/STZ-Induced Diabetic Kidney Disease

LCZ696 (valsartan/sacubitril) has the potential to slow the progression of diabetic kidney disease (DKD) according to previous reports. However, the renoprotective mechanism underlying LCZ696 remains unknown. This study aimed to investigate the therapeutic potential and underlying mechanism of LCZ696 in DKD in a type 2 diabetic (T2D) rat model. This model was established in this experiment by feeding a high-fat diet (HFD) for six weeks with a single dose of streptozotocin (STZ, 30 mg/kg body weight). Valsartan or LCZ696 was orally administered to T2D animals for eight weeks. HFD/STZ rats showed hyperglycemia, impaired insulin secretion, significant increases in urea, creatinine, cytokines, nuclear factor kappa B (NF-κB), oxidative stress, caspase-3 activity, glomerular and tubular damage, glomerulsclerosis, Bax and caspese-3 expressions along with a significant decline in IL-10, antioxidant markers, and Bcl-2 expression. The administration of LCZ696 to diabetic rats reduced the serum concentrations of glucose, urea, and creatinine. In addition, ELISA results demonstrated that diabetic rats treated with LCZ696 exhibited a reduction in inflammatory (IL-1β, TNF-α, IL-6) and an increase in anti-inflammatory (IL-10) cytokine levels. In addition, a notable decrease in NF-κB and caspase-3 activity was observed. At the level of renal tissue homogenate, diabetic animals treated with LCZ696 demonstrated clear restorations in GSH content and other antioxidant enzyme levels, in addition to a significant decrease in TBARS levels. In addition, LCZ696 inhibited the expression of the Bax and cleaved caspase-3 proteins and enhanced the expression of the Bcl-2 protein. Improvements in histopathological changes in kidney tissues confirmed and significantly supported these biochemical findings. In summary, LCZ696 alleviated DKD with possible mechanisms including inhibition of inflammation and apoptosis.