摘要
AIM:To investigate the role of matrix metalloproteinase(MMP)-9 in the pathogenesis of postoperative liver failure(PLF) after extended hepatectomy(EH).METHODS:An insufficient volume of the remnant liver(RL) results in higher morbidity and mortality,and a murine model with 80%-hepatectomy was used.All investigations were performed 6 h after EH.Mice were first divided into two groups based on the postoperative course(i.e.,the PLF caused or did not),and MMP-9 expression was measured by Western blotting.The source of MMP-9 was then determined by immunohistological stainings.Tissue inhibitor of metalloproteinase(TIMP)-1 is the endogenous inhibitor of MMP-9,and MMP-9 behavior was assessed by the experiments in wild-type,MMP-9(-/-) and TIMP-1(-/-) mice by Western blotting and gelatin zymography.The behavior of neutrophils was also assessed by immunohistological stainings.An anti-MMP-9 monoclonal antibody and a broadspectrum MMP inhibitor were used to examine the role of MMP-9.RESULTS:Symptomatic mice showed more severe PLF(histopathological assessments:2.97 ± 0.92 vs 0.11 ± 0.08,P < 0.05) and a higher expression of MMP-9(71085 ± 18274 vs 192856 ± 22263,P < 0.01).Nonnative leukocytes appeared to be the main source of MMP-9,because MMP-9 expression corresponding with CD11b positive-cell was observed in the findings of immunohistological stainings.In the histopathological findings,the PLF was improved in MMP-9(-/-) mice(1.65% ± 0.23% vs 0.65% ± 0.19%,P < 0.01) and it was worse in TIMP-1(-/-) mice(1.65% ± 0.23% vs 1.78% ± 0.31%,P < 0.01).Moreover,neutrophil migration was disturbed in MMP-9(-/-) mice in the immunohistological stainings.Two methods of MMP-9 inhibition revealed reduced PLF,and neutrophil migration was strongly disturbed in MMP-9-blocked mice in the histopathological assessments(9.6 ± 1.9 vs 4.2 ± 1.2,P < 0.05,and 9.9 ± 1.5 vs 5.7 ± 1.1,P < 0.05).CONCLUSION:MMP-9 is important for the process of PLF.The initial injury is associated with MMP-9 derived from neutrophils,and MMP-9 blockade reduces PLF.MMP-9 may be a potential target to prevent PLF after EH and to overcome an insufficient RL.
AIM: To investigate the role of matrix metalloproteinase (MMP)-9 in the pathogenesis of postoperative liver failure (PLF) after extended hepatectomy (EH).
METHODS: An insufficient volume of the remnant liver (RL) results in higher morbidity and mortality, and a murine model with 80%-hepatectomy was used. All investigations were performed 6 h after EH. Mice were first divided into two groups based on the postoperative course (i.e., the PLF caused or did not), and MMP-9 expression was measured by Western blotting. The source of MMP-9 was then determined by immunohistological stainings. Tissue inhibitor of metalloproteinase (TIMP)-1 is the endogenous inhibitor of MMP-9, and MMP-9 behavior was assessed by the experiments in wild-type, MMP-9(-/-) and TIMP-1(-/-) mice by Western blotting and gelatin zymography. The behavior of neutrophils was also assessed by immunohistological stainings. An anti-MMP-9 monoclonal antibody and a broad-spectrum MMP inhibitor were used to examine the role of MMP-9.
RESULTS: Symptomatic mice showed more severe PLF (histopathological assessments: 2.97 ± 0.92 vs 0.11 ± 0.08, P < 0.05) and a higher expression of MMP-9 (71085 ± 18274 vs 192856 ± 22263, P < 0.01). Nonnative leukocytes appeared to be the main source of MMP-9, because MMP-9 expression corresponding with CD11b positive-cell was observed in the findings of immunohistological stainings. In the histopathological findings, the PLF was improved in MMP-9(-/-) mice (1.65% ± 0.23% vs 0.65% ± 0.19%, P < 0.01) and it was worse in TIMP-1(-/-) mice (1.65% ± 0.23% vs 1.78% ± 0.31%, P < 0.01). Moreover, neutrophil migration was disturbed in MMP-9(-/-) mice in the immunohistological stainings. Two methods of MMP-9 inhibition revealed reduced PLF, and neutrophil migration was strongly disturbed in MMP-9-blocked mice in the histopathological assessments (9.6 ± 1.9 vs 4.2 ± 1.2, P < 0.05, and 9.9 ± 1.5 vs 5.7 ± 1.1, P < 0.05).
CONCLUSION: MMP-9 is important for the process of PLF. The initial injury is associated with MMP-9 derived from neutrophils, and MMP-9 blockade reduces PLF. MMP-9 may be a potential target to prevent PLF after EH and to overcome an insufficient RL.
基金
Supported by Partially by Grants to Nguyen JH from the Deason Foundation(Sandra and Eugene Davenport,Mayo Clinic CD CRT-II),the AHA(0655589B) and NIH(R01NS051646-01A2)
the Grant to Hori T from the Uehara Memorial Foundation (200940051)
