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.
ABSTRACT
ObjectiveTo observe the effect of acetylcholine (ACh) on lipopolysaccharide (LPS) induced inflammatory model of rat alveolar macrophages, and to observe the effect of the acetylcholinesterase inhibitor physostigmine (Phy) on the anti-inflammatory effect of ACh.Methods The rat alveolar macrophages NR8383 were cultured in vitro, which were divided into five groups: blank control group, LPS group (stimulated with 1 mg/L LPS for 12 hours), LPS+ ACh group (0.01, 0.1, 1, 10, 100μmol/L of ACh were added for 5 minutes before LPS stimulation), LPS+ Phy group (1 mmol/L Phy was added for 5 minutes before LPS stimulation), and LPS+ ACh+ Phy group (1 mmol/L Phy and 10μmol/L ACh were added for 5 minutes before LPS stimulation). The supernatants were collected in each group, the enzyme-linked immunosorbent assay (ELISA) was used to assay the contents of tumor necrosis factor-α (TNF-α), interleukins (IL-1β, and IL-6). The activity of acetylcholine esterase (AChE ) in the supernatant was also determined.Results① The contents of TNF-α (ng/L: 605.09±57.13 vs. 34.07±8.62), IL-1β (ng/L: 377.09±28.55 vs. 32.33±10.62) and IL-6 (ng/L: 558.04±77.45 vs. 42.62±11.21) in the LPS group were significantly higher than those in the blank control group (allP 0.05). Nevertheless, 10μmol/L and 100μmol/L ACh notably reduced the production of TNF-α (ng/L: 451.19±30.67, 332.19±32.19 vs. 604.96±22.56), IL-1β(ng/L: 261.08±24.78, 143.98±28.39 vs. 367.06±10.44) and IL-6 (ng/L: 342.75±54.60, 235.48±29.75 vs. 562.69±63.34) in the culture supernatants compared with the LPS group (allP< 0.05).③ The activity of AChE in the LPS group was significantly higher than that in the blank control group (kU/L: 5.21±0.63 vs. 3.09±0.10,P< 0.05). The activity of AChE was successfully inhibited by 1 mmol/L acetylcholinesterase inhibitor Phy pretreatment compared with that in the LPS group (1.51±0.12 vs. 5.21±0.63,P< 0.05).④ The level of TNF-α (ng/L: 183.17±35.44 vs. 451.19±30.67), IL-1β (ng/L: 91.49±12.27 vs. 261.08±24.78) and IL-6 (ng/L: 108.17±22.82 vs. 342.75±54.60) in the culture supernatants of LPS+ ACh+ Phy group was significantly decreased as compared with LPS+ ACh group (allP< 0.05).Conclusions ACh with the final concentrations of 10μmol/L and 100μmol/L can inhibit the LPS induced inflammatory reaction in alveolar macrophages. The acetylcholinesterase inhibitor Phy can reinforce the ACh-mediated anti-inflammatory effect on alveolar macrophages inflammatory model.