Abstract: Objective The purpose of this study was to explore implication of serum matrix metalloproteinase 1 (MMP-1) and interleukin-6 (IL-6) level changes in patients with primary biliary cholangitis (PBC)during ursodeoxycholic acid (UDCA) treatment. Methods 52 patients with PBCand 50 healthyindividuals were enrolled in our hospital between January 2022 and January 2024, and all patients received UDCA treatment for six months. Serum MMP-1 and IL-6 levels were detected by ELISA,multivariate Logistic regression analysis was applied to reveal impacting factors, and receiver operating characteristic (ROC) curve was used to evaluate predicting efficacy. Results At presentation, serum MMP-1 level in patients with PBC was (8.6±1.9)ng/mL, much lower than [(12.1±2.8)ng/mL, P<0.05], while serum IL-6 level was (9.8±2.4)pg/mL, much higher than [(6.1±1.5)pg/mL, P<0.05] in the healthy individuals; by end of six month treatment, serum MMP-1 level increased and serum IL-6 level decreased (P<0.05)in patients with PBC; baseline serum MMP-1 level in 17 patients with Ludwig phase Ⅲ/Ⅳ was much lower, while serum IL-6 level was much higher than in 35 patients with Ludwig phase Ⅰ/Ⅱ (P<0.05); complete response (CR) rate in our series was 59.6%(31/52) by end of six month observation; percentages of Ludwig phase Ⅲ/Ⅳ(76.2% vs. 3.2%), concomitant fatty liver (47.6% vs. 9.7%) and serum anti-mitochondrial antibody negative (38.1% vs. 12.9%), as well as total serum bilirubin (TSB) levels [(37.6±11.4)μmol/Lvs. (19.1±1.6)μmol/L], MMP-1[(7.6±1.5)ng/mL vs. (9.3±1.7)ng/mL] and IL-6 levels [(11.4±2.8)pg/mL vs. (9.0±1.8)pg/mL] in patients with incomplete response (ICR) were significantly different compared to in those with CR (P<0.05); multivariate Logistic regression analysis showed that Ludwig phase Ⅲ/Ⅳ, elevated TSB and IL-6 and decreased serum MMP-1 levels were all the independent risk factors impacting response to UDCA treatment(P<0.05);ROC analysis demonstrated that serum MMP-1 level lower than 8.0 ng/mL or serum IL-6 level higher than 10.6pg/mL hinted poor response to UDCA treatment (P<0.05). Conclusion Surveillance of serum MMP-1 and IL-6 level changes might help predict response to UDCA treatment in patients with PBC, which warrants further clinical investigation.

Key words: Primary biliary cholangitis, Ursodeoxycholic acid, Matrix metalloproteinase 1, Interleukin 6, Short-term response, Therapy