Therapeutic potential of Garcinia kola against experimental toxoplasmosis in rats

Abstract

Abstract Cerebral toxoplasmosis, the most common opportunistic infection in immunocompromised individuals, is increasingly reported in immunocompetent individuals due to mutant strains of Toxoplasma gondii, which, furthermore, are reported to be resistant to available treatments. We assessed the therapeutic potential of Garcinia kola, a medicinal plant reported antiplasmodial and neuroprotective properties, against experimental toxoplasmosis in rats. Severe toxoplasmosis was induced in male Wistar rats (156.7±4.1g) by injection with 10 million tachyzoites in suspension in 500 µL of saline (intraperitoneal), and exclusive feeding with a low-protein diet (7% protein [weight by weight]). Then, animals were treated with G. kola hexane, dichloromethane, and ethyl acetate fractions. Footprints were analysed and the open field and elevated plus maze ethological tests were performed when signs of severe disease were observed in infected controls. After sacrifice, blood samples were processed for Giemsa staining, organs for haematoxylin and eosin staining, and brains for Nissl staining and cell counting. Compared to non-infected animals, the infected control animals had significantly lower body weights (30.27%↓, P = 0.001), higher body temperatures (P = 0.033) at sacrifice, together with signs of cognitive impairment and neurologic deficits such as lower open field arena centre entries (P < 0.001), elevated plus maze open arm time (P = 0.029), and decreased stride lengths and step widths (P < 0.001), as well as neuronal loss in various brain areas. G. kola ethyl acetate fraction prevented or mitigated most of these signs. Our data suggest that G. kola ethyl acetate fraction has therapeutic potential against cerebral toxoplasmosis.