Background: The cytokine cascade in the immunopathogenesis of malaria infection had been widely studied.
However, their specific association with survival and severe infection remained obscure.
Methods: The study investigated the cytokine profiles and histopathological features of malaria in the severe
infection and survival models by using male ICR mice and male Sprague Dawley rats respectively.
Results: The severe model, the infected ICR mice, exhibited a high parasitemia with 100% mortality after
peak parasitemia at day 5 post-infection. The survival model, the infected Sprague Dawley rats, showed
mild parasitemia with full recovery by day 14 of infection. Both severe and survival models showed similar
histopathological severity during peak parasitemia. The severe model produced highly elevated levels of proinflammatory
cytokines, TNF-α and IL-1α, and low levels of the anti-inflammatory cytokine, IL-4; while the
survival model showed low levels of TNF-α and IL-1α with high levels of IL-4.
Conclusion: There were differences in the pathogenesis of the severe and survival models of malaria infection.
These could be a basis for immunotherapy of malaria in the future.
Garcinia hombroniana has been used in Malay traditional medicine to treat various disorders such as abdominal pain and gonorrhea, and little is known about its toxicological properties. This study investigated the acute toxicological effects of the plant’s leaves aqueous extract using theoral acute toxic class (ATC) method. Twenty-four female Sprague-Dawley rats were divided into T1, T2, T3 and control groups. The T1, T2 and T3 rats administered a single oral dose of 300, 2000 and 5000 mg/kg of G. hombroniana leaves aqueous extract, respectively.The animals were checked daily for abnormal clinical signs and mortality rate for 14 days. The body weight, daily food and water consumption were recorded. The haematological and biochemical parameters of blood as well as relative organ weight and tissues histology such as heart, kidney, liver and spleen were evaluated. Results have shown significantly decreased (p< 0.05) food and water consumption in T2 and T3 rats, which returned to normal after 72 hr post administration. No significant differences (p≥ 0.05) in the haematological and serum biochemical parameters in the treated rat groups, compared to the untreated control animals. An increase in the relative weight of spleen was noticed in T3 animals. Congestion of the splenic, hepatic, cardiac and renal tissues was seen in T2 and T3 rats. The oral LD50 was higher than 5000 mg/kg of body weight. Thus, it can be concluded that G. hombroniana aqueous extract shows little toxicity in the laboratory rats and the therapeutic potentials should be further investigated.