Preliminary Study on the In vivo Anti-neuroinflammatory Effects of Khaya grandifoliola and Cymbopogon citratus Polysaccharide Fractions

Aims: To determine the effects of polysaccharide fractions named KGF and CCF respectively for Khaya grandifoliola stem bark and Cymbopogon citratus leaves on Central Nervous System (CNS) depression and on systemic lipopolysaccharide (LPS)-induced brain inflammation and hyperalgesia in BALB/c.

Methodology: BALB/c mice weighing about 25-35 g were used for the experimentation. Depressant effects of polysaccharide fractions were firstly evaluated using Rota Rod and Actophotometer apparatus. Secondly, LPS or saline solution (5 mg/kg) was Intraperitoneally administered (i.p.) 1 hour after oral administration of polysaccharide fractions (100 mg/kg test dose, p.o.) or distilledwater. Then, the hot plate and tail-flick models were performed 1 hour after LPS injection to determine thermal hyperalgesia and brain inflammation, was examined 3 hours after LPS injection by Luminex assay.

Results:Systemic LPS administration resulted in a reduction of pain response latency and an increasing expression of nuclear factor-κB (NF-κB) and pro-inflammatory cytokines interleukin-1β (IL-1β), IL-6, tumor necrosis factor- α (TNF-α) genes in brain after 24 hours. From the results it was observed that treatment with KGF and CCF (100 mg/kg, p.o) significantly attenuated LPS-induced hyperalgesia and overexpression of brain levels of IL-1β, IL-6 and TNF-α genes dependent on inhibition of the NF-κB signaling pathway in BALB/c without CNS depressant properties.

Conclusion: The present findings confirm the potential of KGF and CCF in the treatment of neuroinflammation-related diseases and it warrant further testing for the development of a new chemical entities. However further studies are required for determination of effective dose and mechanism of action associated.