Neuroprotective Effects of Cistanoside A against Cadmium-induced Neurotoxicity via Keap1/Nrf2/NF-kB Signaling: In Vivo and In Silico approaches.

Mitochondrial oxidative stress is a major factor of neurological diseases by generating and accumulating ROS, LPO, and 4-HNE in the brain. Here, cadmium chloride (CdCl2) is injected into mice (5 mg/kg per mouse, I.P.) to establish an animal model and to analyze elevated oxidative stress, neuroinflammation, apoptosis, reduced body weight, and synaptic impairment. The therapeutic agent Cistanoside A (CA) was administered to the CdCl2-treated mice group at a dose of 60 mg/kg per mouse for 4 weeks, P.O. The CdCl2 + CA-treated mice group reversed the elevated levels of ROS, LPO, GSH, and SOD in the mice brain homogenates and improved the levels of endogenous antioxidant biomarkers (Nrf2 and HO-1). Similarly, CA reduced neuroinflammation, as analyzed with GFAP, Iba-1, p-NFKB, IL-1β, and TNF-α in the CdCl2 + CA co-treated group. Furthermore, CA preserved neuronal integrity and morphology in the mouse brain, as analyzed via western blot (i.e., Bax and Bcl2), Nissl staining, Hematoxylin & Eosin staining, and immunohistochemistry. In silico, our therapeutic agent CA shows strong interaction with the active site of Keap-1 and enhances the activity of NRF2 to inhibit CdCl2-induced oxidative stress and downstream signaling. Accumulatively, the therapeutic agent CA (60 mg/kg per mouse) potentially reversed oxidative stress, neuroinflammation, and the progression of neurodegeneration in the mouse CdCl2-injected neurotoxic model.