Aqueous extracts of Ocimum grasstimum inhibits lipopolysaccharide-induced interleukin-6 and interleukin-8 expression in airway epithelial cell BEAS-2B.

OBJECTIVE: To investigate the antiinflammatory activities of aqueous extract of Occimum gratissmium (OGE) with emphasis on expression of proinflammatory cytokines in Lipopolysaccharide (LPS)-stimulated epithelial cell BEAS-2B.
METHODS: Effects of OGE on cell viability were determined by MTT assay. mRNA expression were analyzed by and reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time PCR. Activation of kinase cascades was investigated by immunoblot. Intracellular reactive oxygen species (ROS) was analyzed by flow cytometry.
RESULTS: OGE (<200 μg/mL) treatment or pretreatment and following LPS exposure slightly affected viability of BEAS-2B cells. Increase of interleukin (IL)-6 and IL-8 and the elevated level of intracellular ROS in LPS-stimulated BEAS-2B cells were diminished by OGE pretreatment in a dose-dependent manner. OGE suppressed inflammatory response-associated mitogen-activated protein kinases (MAPKs) and Akt activation. Additionally, OGE pretreatment increased level of cellular inhibitor of κBα (IκBα) and inhibited nuclear translocation of nuclear factor kappa B (NF-κB).
CONCLUSION: These findings indicate that significant suppression of IL-6 and IL-8 expressions in LPS-stimulated BEAS-2B cells by OGE may be attributed to inhibiting activation of MAPKs and Akt and consequently suppressing nuclear translocation of NF-κB.