Effect Of IL-22 On CollagenⅠExpression In Cultured Cardiac Fibroblasts From Mice In Vitro

OBJECTIVE:To observe changes of the gene transcription and protein expression of collagen Ⅰ in cultured BALB/c mice cardiac fibroblasts(CFs) in vitro stimulated by IL-22, and to explore the effect of IL-22 on the expression of collagen Ⅰ in CFs.METHODS:Cardiac fibroblasts were isolated from 7-day-old BALB/c mice, then identified by morphology and immunofluorescence. The cells were collectd after IL-22 treatment 48 h. The mRNA was extracted and changed into cDNA by reverse transcription,the expression levels of collagen 1a1 (col1a1) mRNA in CFs after IL-22 stimulation were detected realtime fluorescence quantitative PCR; The expression levels of collagen type Ⅰ were detected by immunofluorescence, and analyzed the images gray value to meansure the change of the expression of collagen type Ⅰ.RESULTS:1. Compared with the control CFs, the level of COL1A1 mRNA expression from the CFs in vitro with 1ng/mL IL-22 stimulation for 48 h was significantly decreased (P< 0.05), and the level of COL1A1 mRNA expression from the CFs in vitro with 100ng/mL IL-22 stimulation for 48 h was significantly increased (P< 0.05). Compared with the CFs in vitro with 100ng/mL IL-22 stimulation for 48 h, the level of COL1A1 mRNA expression from the CFs in vitro with 100ng/mL IL-22 and 100μM S3I-201 stimulation for 48 h was significantly decreased(P< 0.01).2. Compared with the control CFs, the level of COL1A1 expression from the CFs in vitro with lng/mL IL-22 stimulation for 48 h was significantly decreased (P< 0.05), and the level of COL1A1 expression from the CFs in vitro with 100ng/mL IL-22 stimulation for 48 h was significantly increased (P< 0.05). Compared with the CFs in vitro with 100ng/mL IL-22 stimulation for 48 h, the level of COL1A1 expression from the CFs in vitro with 100ng/mL IL-22 and 100μM S3I-201 stimulation for 48 h was significantly decreased(P< 0.05). CONCLUSION:The collagen I expression of the cultured CFs in vitro were regulated differently by IL-22 stimulation with different concentrations. The collagen Ⅰ gene transcription and protein expression was down-regulated with IL-22 stimulation for the low concentration (1ng/mL), but up-regulated for the high concentration (100ng/mL). The collagen I gene transcription and protein expression was up-regulated with IL-22 stimulation for the high concentration of IL-22 may through the STAT3 pathway.