MicroRNA-132 inhibits inflammation of alveolar macrophages by regula-ting cholinergic anti-inflammatory pathway / 中国病理生理杂志

ABSTRACT

AIM:To investigate the role of microRNA-132 (miR-132) on alveolar macrophage inflammation. METHODS: Rat alveolar macrophage cell line NR8383 was transfected with miR-132 mimic, mimic negative control ( NC) , miR-132 inhibitor, or inhibitor NC.The cells were divided into transfection group, transfection +lipopolysaccha-ride ( LPS) group, and transfection +LPS +acetylcholine ( ACh) group.The mRNA expression of acetylcholinesterase ( AChE) was detected by real-time PCR.The protein levels of AChE, signal transducer and activator of transcription 3 (STAT3) and phosphorylated STAT3 (p-STAT3) in the cells, and nuclear factor-κB (NF-κB) in the cytoplasm and nu-cleus were analyzed by Western blot.The activity of AChE in the culture supernatant was measured by AChE activity assay kit.The nuclear translocation of NF-κB was detected by immunofluorescence assay.RESULTS: Up-regulation or down-regulation of miR-132 had no effect on the mRNA expression of AChE.However, up-regulation of miR-132 decreased the protein level of AChE compared with mimic NC group (P<0.05).Transfection with miR-132 inhibitor increased the pro-tein expression of AChE compared with inhibitor NC group ( P<0.05 ) .In the alveolar macrophages treated with LPS+ACh, the inhibition of nuclear translocation of NF-κB p65 in miR-132 mimic group was more effective than that in mimic NC group ( P<0.05) .The inhibitory effect in miR-132 inhibitor group was weaker than that in inhibitor NC group ( P<0.05 ) .The inhibitory effect of miR-132 mimic on the protein levels of STAT3 and p-STAT3 was stronger than that of mimic NC (P<0.05).CONCLUSION:miR-132 in LPS-stimulated alveolar macrophages reinforced ACh-mediated anti-inflam-matory reaction by targeting AChE to suppress ACh hydrolyzation, which was related to the suppression of NF-κB and STAT3 activation.