Neuroprotective Effect of Saroglitazar on Scopolamine-Induced Alzheimer's in Rats: Insights into the Underlying Mechanisms.

Abstract

Alzheimer's disease (AD) is one of the most prevalent and progressive neurodegenerative disorders, hallmarked by increased amyloid-β deposition and enhanced oxidative load in the brain, ensuing cognitive decline. The present study is aimed at elucidating the neuroprotective effect of saroglitazar, a dual peroxisome-proliferator-activated receptor (PPARα/γ) agonist used in the treatment of diabetic dyslipidemia, against memory impairment induced by intraperitoneal scopolamine injection. 30 male Wistar rats were randomly divided into the following five groups: (A) Veh + Veh, (B) SGZ + Veh, (C) Veh + SCOP, (D) DPZ + SCOP, and (E) SGZ + SCOP. Rats of the respective groups were pretreated with saroglitazar (10 mg/kg, p.o.) and donepezil (3 mg/kg, p.o.) once daily for 16 days. During the final 9 days of the study, a daily injection of scopolamine (3 mg/kg, i.p.) was administered to the respective groups. Adjacent to the scopolamine injection, behavioral tests such as the open field, Y maze, novel object recognition test, and Morris water maze were conducted to assess learning and memory. Additionally, biochemical parameters such as acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), nitric oxide (NO), malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), brain-derived neurotrophic factor (BDNF), β-amyloid levels, and NF-κB were measured in the hippocampus. The rats that received scopolamine injections showed significantly impaired short-term spatial and learning memory. This was associated with an increase in β-amyloid, iNOS, nitric oxide (NO), malondialdehyde, NF-κB, and TNF-α levels in the hippocampus of AD rats. On the other hand, saroglitazar has provided promising data on its protective role in cognition by protecting the BDNF, SOD, and GSH decline. As a result, saroglitazar was found to be a promising therapy in AD by upregulating the antioxidant status and cholinergic activity and preventing memory loss. Collectively, findings in the present study revealed that saroglitazar protected AD by suppressing scopolamine-mediated learning and memory deficits, oxidative stress, and cholinergic damage. Studying these mechanisms may conclude the protective role of saroglitazar against AD. However, further studies in transgenic animals will provide numerous insights into treatment mechanisms and contribute to developing a therapeutic intervention for AD.