关键词: 多房棘球绦虫, 肝纤维化, 肝星状细胞, ADAM金属肽酶结构域23

Abstract:

Objective To investigate the changes of ADAM metallopeptidase domain 23 (ADAM23) expression during the progression of hepatic fibrosis in mice infected with Echinococcus multilocularis (Em). Methdos Thirty-six C57BL/6 mice were randomly divided into six groups, of 6 mice each group, including the 1-month sham group, 1-month Em infection group, 3-month sham group, 3-month Em infection group, 6-month sham group, and 6-month Em infection group. Mice in the Em infection groups were injected with Em protoscolex suspensions (2 000 protoscoleces/mouse) via the portal vein, while animals in the sham groups received an equal volume of physiological saline. Mouse liver tissues were sampled 1, 3 and 6 months post-infection. Hepatic lobule structure, inflammatory cell infiltration, granuloma formation, and collagen deposition were observed by HE and Sirius red staining, and target protein expression was quantified using immunohistochemical staining. Mouse liver tissues from the 3-month sham and 3-month Em infection groups were sampled for proteomic analyses, and the translational and transcriptional expression of ADAM23, α-smooth muscle actin (α-SMA), and collagen type 1 alpha 1 chain (COL1A1) was determined in mice using Western blotting and RT-qPCR assays. Human hepatic stellate cells (HSCs) were seeded onto 6-well plates at a density of 2 × 10⁵ cells/well and divided into the si-ADAM23 group, TGF-β1 + small interfering RNA (siRNA) group, TGF-β1 + si-ADAM23 group, siRNA group, and control group. Cells were transfected with 600 ng siRNA-ADAM23 in the si-ADAM23 group, received 10 ng TGF-β1 and 600 ng siRNA cells in the TGF-β1 + siRNA group, received 10 ng TGF-β1 and 600 ng siRNA-ADAM23 in the TGF-β1 + si-ADAM23 group, received 600 ng siRNA in the siRNA group, and received an equal volume of transfection reagents in the control group. The translational and transcriptional expression of ADAM23, α-SMA, and COL1A1 was detected in HSCs using Western blotting and RT-qPCR assays. Results HE staining showed hepatic lobule structural derangements with infiltration of a large number of inflammatory cells in Em-infected mice. Sirius red staining revealed that the areas of hepatic fibrosis were (2 167.00 ± 356.70) μm², (163.10 ± 25.41) μm², (3 792.00 ± 596.00) μm², (159.40 ± 3.97) μm², (5 436.00 ± 427.50) μm², (274.40 ± 38.01) μm² in the 1, 3, and 6-month Em infection groups and corresponding sham groups, respectively, with significant differences seen between the infection and sham groups (t = 14.71, 26.68 and 37.91; all P < 0.05). Proteomic analysis showed that the ADAM23 protein abundance was 9 250 ± 5 628 of in the 3-month Em infection group. Western blotting assay showed significant differences in ADAM23, α-SMA, and COL1A1 protein expression between the 1-, 3-, 6-month Em infection groups and their corresponding sham groups (t = 13.5, 15.8, 26.1; 4.37, 6.75, 15.82; 5.00, 8.65 and 21.45; all P < 0.05). RT-qPCR assay quantified significant differences in the relative mRNA expression of adam23, acta2, and col1a1 between the 1-, 3-, 6-month Em infection groups and their corresponding sham groups (t = 5.44, 6.44, 9.95; 4.13, 7.43, 25.10; 4.85, 22.60 and 39.50; all P values < 0.05). Immunohistochemistry showed significant differences in the area of positive ADAM23, α-SMA, and COL1A1 expression the 1-, 3-, 6-month Em infection groups and their corresponding sham groups (t = 26.68, 17.55, 52.07; 24.98, 36.70, 49.47; 16.24, 45.48 and 77.45; all P < 0.05). Spearman correlation analysis revealed that the area of positive ADAM23 expression positively correlated with the areas of positive α-SMA (r = 0.83, P < 0.05) and COL1A1 expression (r = 0.87, P < 0.05), and Sirius red staining (r = 0.88, P < 0.05) in liver samples of Em-infected mice. RT-qPCR assay quantified that the relative adam23 mRNA expression was 1.03 ± 0.14, 0.92 ± 0.09, and 0.23 ± 0.04 in HSCs in the control, siRNA, and si-ADAM23 groups, respectively, and higher relative adam23 mRNA expression was found in the siRNA group than in the si-ADAM23 group (t = 12.23, P < 0.05). Western blotting assay showed that the relative ADAM23 protein expression was 0.15 ± 0.01, 1.20 ± 0.11, and 0.41 ± 0.15 in the siRNA group, TGF-β1 + siRNA group, and TGF-β1 + si-ADAM23 group, statistically significant differences were observed both when comparing the siRNA group with the TGF-β1 + siRNA group, and when comparing the TGF-β1 + siRNA group with the TGF-β1 + si-ADAM23 group (t = 16.52 and 12.44, both P < 0.05), and the relative α-SMA protein expression was 0.31 ± 0.09, 1.21 ± 0.04, and 0.87 ± 0.01 in the siRNA group, TGF-β1 + siRNA group, and TGF-β1 + si-ADAM23, statistically significant differences were observed both when comparing the siRNA group with the TGF-β1 + siRNA group, and when comparing the TGF-β1 + siRNA group with the TGF-β1 + si-ADAM23 group (t = 27.85 and 10.67, both P values < 0.05), while the relative COL1A1 protein expression was 0.61 ± 0.16, 0.95 ± 0.02, and 0.49 ± 0.07 in the siRNA group, TGF-β1 + siRNA group, and TGF-β1 + si-ADAM23 group, statistically significant differences were observed both when comparing the siRNA group with the TGF-β1 + siRNA group, and when comparing the TGF-β1 + siRNA group with the TGF-β1 + si-ADAM23 group (t = 5.77 and 7.96, both P values < 0.05). Conclusion ADAM23 expression increases with the progression of Em infections and positively correlates with the degree of hepatic fibrosis. ADAM23 is a novel potential therapeutic target for hepatic fibrosis caused by Em infections.

Key words: Echinococcus multilocularis, Hepatic fibrosis, Hepatic stellate cells, ADAM23