Evaluating the Oxidative Stress Reducing Potentials of Sub-Fractions of Capsicum Frutescens L. Aqueous Extract on Early Established Plasmodium in Mice.

Purpose: Resistance to malaria parasites has overwhelming impacts on the host's antioxidant microenvironment, stimulating oxidative stress during nutrient hunt. Hence, settlers in malaria-ravaged communities have resorted to plant use for fever and malaria due to its availability and affordability. This work assessed the oxidative stress status through antioxidant parameters of sub-fractions of Capsicum frutescens L. fruit (CFL) aqueous extract in Plasmodium berghei (NK65)-parasitized mice.

Methods: Two hundred and four (204) mice (combined sexes) weighing 24.0 ± 3.0 g were randomized into seven Groups (n = 4) and intraperitoneally inoculated with parasitized erythrocytes (0.2 mL). Group A = 10 mL/kg normal saline (control), Group B = 10 mg/kg body weight chloroquine, and Groups C-G respectively received 0.5, 1.0, 2.0, 4.0, and 8.0 mg/kg body weight of each sub-fraction. On Days 4 and 8 post-inoculation, mice from each group were euthanized. Blood and liver were taken and prepared using standard procedures to develop homogenates of erythrocytes and liver. Assessment of lipid peroxidation using malondialdehyde (MDA) and antioxidants using superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase concentrations were done in the homogenates.

Results: Treatment with CLF sub-fractions in erythrocytes and liver homogenates significantly reduced (p < 0.05) MDA levels with a concomitant increase in the untreated. Conversely, the treated groups revealed a significant increase in the antioxidant enzymes in a dose-dependent fashion compared with the untreated on Days 4 and 8 post-inoculation. However, sub-fraction B was more pronounced than sub-fractions A and C.

Conclusion: This study suggests that CFL sub-fractions, especially sub-fraction B, possess in vivo antiplasmodial and antioxidant potency against fever and malaria by elevating antioxidant capacity.