Objective:To determine the effects of a recombinant replication-deficient adenovirus encoding human tissue inhibitor of metalloproteinase-4(Ad.TIMP-4) on vascular smooth muscle cell(VSMC) function in vitro and neointi...Objective:To determine the effects of a recombinant replication-deficient adenovirus encoding human tissue inhibitor of metalloproteinase-4(Ad.TIMP-4) on vascular smooth muscle cell(VSMC) function in vitro and neointimal development in the injured rat carotid artery.Methods:Western blotting,gelatin zymography and reverse zymography were used to characterize the expression and functional activity of the TIMP-4 secreted by Ad.TIMP-4-infected VSMCs.The migration and proliferation of VSMCs in vitro were separately detected by using Millicell-PCF invasion chambers and [3H]-thymidine incorporation assay.Immunohistochemistry and morphometric analysis were used to determine the local expression of TIMP-4 and its effect on neointima development in a rat carotid artery balloon injury model.Results:VSMCs infected with Ad.TIMP-4 expressed functionally active human TIMP-4 which increased with the duration of infection.TIMP-4 expression inhibited VSMC migration,but not significantly affect VSMC proliferation.In a balloon-injured rat carotid artery model,a significant 62% reduction in neointimal area was found in Ad.TIMP-4-infected vessels at 14 days after injury.Ad.TIMP-4 infection had no effect on medial area.Conclusion:Our results indicated TIMP-4 over expression can significantly inhibit the migration of cultured VSMCs and prevent neointimal formation after vascular injury.Our findings provide additional evidence that TIMP-4 could play an important role in vascular pathophysiology,and may be an important therapeutic target for future drug development.展开更多
Functional responses to angiotensin Ⅱ (AT-Ⅱ) were determined in aortic vascular smooth muscle cells (VSMCs) from experimental cirrhotic rats. Our data showed that AT-Ⅱ-stimulated extracellular acidification rate (E...Functional responses to angiotensin Ⅱ (AT-Ⅱ) were determined in aortic vascular smooth muscle cells (VSMCs) from experimental cirrhotic rats. Our data showed that AT-Ⅱ-stimulated extracellular acidification rate (ECAR), which was measured by Cytosensor microphysiometry, was significantly reduced in the aortic VSMCs from the cirrhotic rats as compared to those from the control animals. The ability of AT-Ⅱ to promote formation of inositol phosphates, the second messenger produced by the activation of Gq-coupled receptors, was also considerably suppressed in the cirrhotic VSMCs. Furthermore, the maximal p42/44 MAPK phosphorylation stimulated by AT-Ⅱ was significantly reduced in the cirrhotic VSMCs in contrast to that in the normal VSMCs. Taken together, our data clearly demonstrated that the functional responses to AT-Ⅱ was severely suppressed in aortic VSMCs in cirrhosis, indicating the impairment of general Gq-coupled receptor signaling and subsequent biological function in the cirrhotic VSMCs.展开更多
基金Supported by the National Natural Science Foundation of China (30630056)
文摘Objective:To determine the effects of a recombinant replication-deficient adenovirus encoding human tissue inhibitor of metalloproteinase-4(Ad.TIMP-4) on vascular smooth muscle cell(VSMC) function in vitro and neointimal development in the injured rat carotid artery.Methods:Western blotting,gelatin zymography and reverse zymography were used to characterize the expression and functional activity of the TIMP-4 secreted by Ad.TIMP-4-infected VSMCs.The migration and proliferation of VSMCs in vitro were separately detected by using Millicell-PCF invasion chambers and [3H]-thymidine incorporation assay.Immunohistochemistry and morphometric analysis were used to determine the local expression of TIMP-4 and its effect on neointima development in a rat carotid artery balloon injury model.Results:VSMCs infected with Ad.TIMP-4 expressed functionally active human TIMP-4 which increased with the duration of infection.TIMP-4 expression inhibited VSMC migration,but not significantly affect VSMC proliferation.In a balloon-injured rat carotid artery model,a significant 62% reduction in neointimal area was found in Ad.TIMP-4-infected vessels at 14 days after injury.Ad.TIMP-4 infection had no effect on medial area.Conclusion:Our results indicated TIMP-4 over expression can significantly inhibit the migration of cultured VSMCs and prevent neointimal formation after vascular injury.Our findings provide additional evidence that TIMP-4 could play an important role in vascular pathophysiology,and may be an important therapeutic target for future drug development.
文摘Functional responses to angiotensin Ⅱ (AT-Ⅱ) were determined in aortic vascular smooth muscle cells (VSMCs) from experimental cirrhotic rats. Our data showed that AT-Ⅱ-stimulated extracellular acidification rate (ECAR), which was measured by Cytosensor microphysiometry, was significantly reduced in the aortic VSMCs from the cirrhotic rats as compared to those from the control animals. The ability of AT-Ⅱ to promote formation of inositol phosphates, the second messenger produced by the activation of Gq-coupled receptors, was also considerably suppressed in the cirrhotic VSMCs. Furthermore, the maximal p42/44 MAPK phosphorylation stimulated by AT-Ⅱ was significantly reduced in the cirrhotic VSMCs in contrast to that in the normal VSMCs. Taken together, our data clearly demonstrated that the functional responses to AT-Ⅱ was severely suppressed in aortic VSMCs in cirrhosis, indicating the impairment of general Gq-coupled receptor signaling and subsequent biological function in the cirrhotic VSMCs.