PROMOTING ACCESS TO AFRICAN RESEARCH

Tropical Journal of Pharmaceutical Research

Log in or Register to get access to full text downloads.

Remember me or Register



Methanol Extract of Myelophycus caespitosus Inhibits the Inflammatory Response in Lipopolysaccharidestimulated BV2 Microglial Cells by Downregulating NF-kB via Inhibition of the Akt Signaling Pathway

RGPT Jayasooriya, C-H Kang, Y-J Jang, S-H Kang, MG Dilshara, YH Choi, D-O Moon, G-Y Kim

Abstract


Purpose: To determine whether the methanol extract of Myelophycus caespitosus (MEMC) downregulates the expression of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated BV2 microglial cells.
Methods: Reverse transcription-polymerase chain reaction (RT-PCR) together with Western blot analysis was used to evaluate the expression of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin E2
(PGE2) as well as their regulatory genes such as inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), in LPS-stimulated BV2 microglial cells. The level of NO production was analyzed using Griess reaction.
The release of PGE2 was determined using sandwich enzyme-linked immunosorbent assay. The DNA-binding activity of nuclear factor-êB (NF-êB) was measured by electrophoretic mobility shift assay.
Results: MEMC inhibited LPS-induced pro-inflammatory mediators, NO and PGE2, as well as their respective genes, iNOS and COX-2, at both protein and mRNA levels, without any significant cytotoxicity. Treatment with
MEMC also substantially reduced the LPS-induced DNA-binding activity of NF-êB and nuclear translocation of NF-êB subunits p65 and p50 via the inhibition of IêBá phosphorylation and degradation. MEMC promoted
dephosphorylation of Akt that subsequently suppressed the DNA-binding activity of NF-êB in LPS-stimulated BV2 microglial cells.
Conclusion: Collectively, these data suggest that MEMC attenuates expression of pro-inflammatory mediators such as NO and PGE2 by suppression of their regulatory genes through the inhibition of Aktmediated NF-êB activity.

Keywords: Myelophycus caespitosus, Nitric oxide, Prostaglandin E2, Nuclear factor-êB.




http://dx.doi.org/10.4314/tjpr.v11i6.7
AJOL African Journals Online