Protective Effect of Lupeol Against Lipopolysaccharide-Induced Neuroinflammation via the p38/c-Jun N-Terminal Kinase Pathway in the Adult Mouse Brain
This study aimed to evaluate the effect of lupeol against lipopolysaccharide (LPS)-induced neuroinflammation in the cortex and hippocampus of adult mice. Our results showed that systemic administration of LPS induced glial cell production of proinflammatory cytokines, tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS), and interleukin (IL)-1β, while co-treatment with lupeol significantly inhibited the LPS-induced activation of microglia and astrocytes, and decreased the LPS-induced generation of TNF-α, iNOS, and IL-1β. The intracellular mechanism involved in the LPS-induced activation of inflammatory responses includes phosphorylation of P38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK), which was significantly inhibited by lupeol. We further elucidated that lupeol inhibited the LPS-induced activation of the mitochondrial apoptotic pathway and reversed the LPS-induced expression of apoptotic markers such as Bax, cytochrome C, caspase-9, and caspase-3. Taken together; our results suggest that lupeol inhibits LPS-induced microglial neuroinflammation via the P38-MAPK and JNK pathways and has therapeutic potential to treat various neuroinflammatory disorders.
Source: Journal of NeuroImmune Pharmacology - Category: Drugs & Pharmacology Source Type: research