Flavonoid-Rich Fraction of Ocimum gratissimum Attenuates Lipopolysaccharide-Induced Sickness Behavior, Inflammatory and Oxidative Stress in Mice.

Purpose: L. leaves has been traditionally used for management of febrile illnesses and symptoms typified of sickness behavior. In this work we investigated the modulatory effect of flavonoid-rich fraction of leaves (EAFO) on sickness behavior, inflammatory and oxidative stress responses in LPS-challenged mice.

Method: leaf was first extracted with n-hexane, chloroform and methanol, and EAFO was obtained by ethylacetate partitioning of a sequentially resultant methanol extract. The effect of EAFO (25-100 mg/kg) on acute LPS-induced neurobehavioral impairment in an open field test (OFT) and depressive-like behavior in forced swimming test (FST) was investigated. Serum nitrite and TNF-α, as well as myeloperoxidase (MPO), malondialdehyde (MDA), and reduced glutathione (GSH) levels were determined in liver and brain tissues.

Result: EAFO prevented the reduction in locomotor and rearing activity in OFT and the increase in immobility time in FST. The fraction significantly attenuated the elevation of serum TNF- α and nitrite levels. EAFOg reversed LPS-induced increase in MDA, MPO, and nitrite levels and attenuated GSH depletion in liver and brain tissues of mice.

Conclusion: Flavonoid-rich fraction of leaf demonstrated significant modulation of LPS-induced sickness behavior, inflammatory and oxidative stress response in mice. This suggests an important therapeutic strategy in slowing down LPS-mediated hepatic and neuronal disease processes.