Neuroprotective and Anti-inflammatory Effects of Terminalia superba Engler & Diels (Combretaceae): A Potential Therapeutic Approach for Cerebral Malaria

Abstract

Cerebral malaria is one of the most severe complications of malaria, primarily caused by Plasmodium falciparum. The search for alternative or complementary treatments to classical antimalarial therapies is crucial in light of the emergence of drug resistance. Terminalia superba, a tropical medicinal plant, has traditionally been used to treat various diseases, including those with parasitic etiology. This study aims to evaluate the potential of Terminalia superba in managing cerebral malaria. Ethanolic extracts of T. superba were obtained by maceration of the bark of the plant in 70% alcohol. Cytotoxicity and neuroprotection tests were conducted on neurons (SH-SY5Y-neurons) using the MTT method. The activity against neuroinflammation was assessed through the LPS (Lipopolysaccharide) test, measuring cytokines TNF-α, Interleukin 8, Interleukin 6, and Interleukin 1β. The ethanolic extract of Terminalia superba exhibited non-toxic activity on neurons with an IC50 greater than 200 µg/mL. This extract protected astrocytes against oxidative stress induced by H2O2 (500 µM). Cell survival increased from 35% to 45%, 59%, 61%, and 73% at concentrations of 3.125, 12.5, 50, and 200 µg/mL, respectively. Terminalia superba also reduced the overproduction of cytokines by LPS-stimulated neurons, demonstrating its efficacy against neuroinflammation. The ethanolic extract of Terminalia superba, in addition to being non-cytotoxic, possesses antioxidant and anti-inflammatory properties on neurons. These properties could play an important role in the management of cerebral malaria. Further studies should lead to the development of a drug against cerebral malaria based on the bark of T. superba.