[Berberine dose-dependently inhibits the expression of procoagulant and fibrinolytic inhibitory factors in lipopolysaccharide-induced rat type II alveolar epithelial cells].

OBJECTIVE: To observe the effects of berberine on procoagulant and fibrinolytic inhibitory factors produced by rat type II alveolar epithelial cell (AEC II) induced by lipopolysaccharide (LPS). METHODS: AEC II cells (RLE-6TN cells) were cultured in vitro, and the cells in logarithmic growth phase were collected. The cytotoxicity text of berberine was detected by cell counting kit-8 (CCK-8) to determine the drug concentration range according to inhibition concentration of half cells (IC50). The RLE-6TN cells were divided into five groups, the cells in blank control group were cultured in DMEM; the cells in LPS group were stimulated with 5 mg/L LPS; and the cells in berberine pretreatment groups were pretreated with 20, 50 and 80 µmol/L berberine for 1 hour, and then were co-cultured with 5 mg/L LPS. The cells were collected after LPS induced for 24 hours. The protein and mRNA expression levels of tissue factor (TF), tissue factor pathway inhibitor (TFPI) and plasminogen activator inhibitor-1 (PAI-1) in the cells were detected by Western blotting and real-time fluorescence quantification reverse transcription-polymerase chain reaction (RT-qPCR). The levels of activated protein C (APC), precollagen III peptide (PIIIP), thrombin-antithrombin complex (TAT) and antithrombin III (AT III) in the cell supernatant were measured by enzyme linked immunosorbent assay (ELISA). RESULTS: According to the inhibition rate curve, the IC50 of berberine on RLE-6TN cells was 81.16 µmol/L. Therefore, 20, 50 and 80 µmol/L were selected as the intervention concentration of berberine. Compared with the blank control group, the expression and secretion of procoagulant and fibrinolytic inhibitory factors were abnormal in RLE-6TN cells after LPS induced for 24 hours. The protein and mRNA expression levels of TF and PAI-1 in the LPS group were significantly increased, but the protein and mRNA expression levels of TFPI were significantly decreased. Meanwhile, the levels of APC and AT III in the cell supernatant were significantly decreased, while the levels of PIIIP and TAT were significantly increased. After pretreatment with berberine, the abnormal expression and secretion of procoagulant and fibrinolytic inhibitory factors induced by LPS were corrected in a dose-dependent manner, especially in 80 µmol/L. Compared with the LPS group, the protein and mRNA expression levels of TF and PAI-1 in the berberine 80 µmol/L group were significantly decreased [TF protein (TF/GAPDH): 0.45±0.02 vs. 0.55±0.03, TF mRNA (2-ΔΔCt): 0.39±0.08 vs. 1.48±0.11, PAI-1 protein (PAI-1/GAPDH): 0.37±0.02 vs. 0.64±0.04, PAI-1 mRNA (2-ΔΔCt): 1.14±0.29 vs. 4.18±0.44, all P < 0.01] and those of TFPI were significantly increased [TFPI protein (TFPI/GAPDH): 0.53±0.02 vs. 0.45±0.02, TFPI mRNA (2-ΔΔCt): 0.94±0.08 vs. 0.40±0.05, both P < 0.01]. Meanwhile, the levels of APC and AT III in the cell supernatant were significantly increased [APC (µg/L): 1 358.5±26.0 vs. 994.2±23.1, AT III (µg/L): 118.0±7.4 vs. 84.4±2.7, both P < 0.01], while those of PIIIP and TAT were significantly decreased [PIIIP (µg/L): 11.2±0.4 vs. 18.6±0.9, TAT (ng/L): 222.1±2.8 vs. 287.6±7.0, both P < 0.01]. CONCLUSIONS: Berberine could inhibit the LPS-induced expressions of procoagulant and fibrinolytic inhibitory factors in rat AEC II cells and promote the expressions of anticoagulant factors in a dose-dependent manner. Berberine may be a new therapeutic target for alveolar hypercoagulability and fibrinolysis inhibition in acute respiratory distress syndrome (ARDS).