Effect of ?-MSH on the expression of CD14 and TLR4 mRNA induced by LPS in mouse peritoneal macrophages / 中国病理生理杂志

ABSTRACT

AIM: To observe the effects of ?-MSH on the expression of CD14 and TLR4 mRNA in mou se peritoneal macrophages induced by LPS and explore the mechanisms of ?-MSH ag ainst LPS. METHODS: BALB/C mouse peritoneal macrophages were cultured in the presence of LPS or LPS plus ?-MSH, and the expressions of CD14 and TLR4 mRNA were detected with the m ethod of reverse transcription polymerase chain reaction (RT-PCR). RESULTS: It was found that native murine macrophages o nly expressed a small amount of CD14 and TLR4 mRNA. Both CD14 and TLR4 mRNA expr ession to LPS in mouse macrophages increased significantly than those of contro l group at 6 h and maintained high level until 24 h when they reached to the pea k. Then the expression of CD14 mRNA backed to the normal gene expression baselin e, while TLR4 mRNA had excessive expression at 48 h. In presence of LPS and ?- MSH, the expression of CD14 and TLR4 mRNA decreased remarkably than those of L PS group (P0.05). Only when the dose s of ?-MSH attained to 1, 10 or 100 nmol/L,?-MSH could affect LPS-stimulated e xpression of CD14 and TLR4 mRNA (P0.05). CONCLUSION: These studies suggest that effects of ?-MSH against LPS are associated with its suppressing the critical receptor (CD14 and TLR4) expression of the LPS signal transduction and inhibiting the activation of macrophages.