# Tabernaemontana stapfiana Britten (Apocynaceae) Stem Bark Prevents Alcl3-Induced Cognitive Disability: Antioxidant and Anti-Inflammatory Activities in Wistar Rats

## TL;DR

This study shows that extracts from Tabernaemontana stapfiana stem bark can protect against cognitive impairment caused by aluminum chloride in rats by reducing oxidative stress and inflammation.

## Contribution

The study demonstrates the antioxidant and anti-inflammatory effects of T. stapfiana extracts in preventing AlCl3-induced cognitive disability in Wistar rats.

## Key findings

- Aqueous and ethanol extracts of T. stapfiana reduced inflammatory cytokines like IL-10, TNF-α, IL-1β, and IL-6 in AlCl3-treated rats.
- The extracts improved the oxidant-antioxidant balance by lowering MDA and NO levels while increasing SOD and GSH concentrations.
- T. stapfiana extracts prevented oxidative stress and inflammation in the brain, mitigating cognitive impairment caused by AlCl3.

## Abstract

The present study aimed to evaluate the protective effects of aqueous and ethanol extracts of Tabernaemontana stapfiana (T. stapfiana) on cognitive disability induced by aluminum chloride (AlCl3) in Wistar rats. Forty-five Wistar rats were distributed in different groups of five animals each. Test groups were daily given AlCl3 (100 mg/kg) following by the doses of the extracts for 21 days. At the end of treatment period, rats were sacrificed and the brain homogenate and serum were prepared and used to evaluate oxidative stress in brain and serum cytokines using colorimetric tests and ELISA, respectively. The findings of this study showed that reduced brain, body weight, and antioxidant enzymes (reduced glutathione [GSH], catalase [CAT], and superoxide dismutase [SOD]), while it increases oxidant biomarkers (malondiadehyde (MDA), nitric oxide (NO) and inflammatory cytokines (IL-10, TNF-α, IL-1β, and IL-6). Therefore, the administration of aqueous or ethanol extracts of T. stapfiana stem bark significantly (p  < 0.001) reduced the IL-10, TNF-α, IL-1β, and IL-6 levels in AlCl3-treated rats compared to non treated rats. Moreover, the extracts significantly (p  < 0.001) changed the oxidant–antioxidant balance by reducing the MDA and NO levels, while increasing SOD and GSH concentrations caused and NO in AlCl3-treated rats as compared to nontreated rats. Conclusively, aqueous or ethanol extracts of T. stapfiana stem bark prevented the oxidative stress and inflammation in brain, which made the brain to be not change after administration of the causative agent of cognitive impairment (CI), AlCl3.