Deficiencies in vitamins or other factors(B6,B12,folic acid, betaine)and genetic disorders for the metabolism of the non-protein amino acid-homocysteine(Hcy)lead to hyperhomocysteinemia(HHcy).HHcy is an integral compo...Deficiencies in vitamins or other factors(B6,B12,folic acid, betaine)and genetic disorders for the metabolism of the non-protein amino acid-homocysteine(Hcy)lead to hyperhomocysteinemia(HHcy).HHcy is an integral component of several disorders including cardiovascular disease,neurodegeneration,diabetes and alcoholic liver disease.HHcy unleashes mediators of inflammation such as NFκB,IL-1β,IL-6,and IL-8,increases production of intracellular superoxide anion causing oxidative stress and reducing intracellular level of nitric oxide(NO),and induces endoplasrnic reticulum(ER)stress which can explain many processes of Hcy-promoted cell injury such as apoptosis, fat accumulation,and inflammation.Animal models have played an important role in determining the biological effects of HHcy.ER stress may also be involved in other liver diseases such as α_1-antitrypsin(α_1-AT)deficiency and hepatitis C and/or B virus infection.Future research should evaluate the possible potentiative effects of alcohol and hepatic virus infection on ER stress-induced liver injury,study potentially beneficial effects of lowering Hcy and preventing ER stress in alcoholic humans,and examine polymorphisrn of Hcy metabolizing enzymes as potential risk-factors for the development of HHcy and liver disease.展开更多
OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, ...OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, cilazapril, on the progressive renal injury in spontaneous hypertensive rats (SHR) with diabetes. METHODS: Diabetic hypertensive rats (SHR-DM) were induced by streptozotozin injected in male SHR (7-week-old),and divided into an untreated and three treated groups: 1) cilazapril treated group; 2) bosentan+amlodipine treated group; and 3) amlodipine treated group. Wistar Kyoto rats (WKY) and SHR rats served as normotensive and hypertensive control, respectively. The mean arterial blood pressure, renal function, endothelin and angiotensin II levels as well as the protein expression of renal extracellular matrix components and transforming growth factor (TGF)-beta1 were determined at the end of the 4th week. RESULTS: Mean arterial blood pressure significantly increased in SHR and SHR-DM rats compared to WKY rats. All the therapies reduced the blood pressure to normal levels. However, the enhanced urinary protein excretion, the decreased creatinine clearance as well as the increased plasma and intrarenal endothelin and angiotens in II levels were found in the untreated SHR-DM and prevented by treatment with bosentan+amlodipine and cilazapril. Similarly, these two kinds of therapies in SHR-DM abolished the overexpression of renal TGF-beta1 by Western blot analysis and reduced the accumulation of collagen type IV, laminin and fibronectin proteins by an immunochemical approach. Amlodipine monotherapy had no detectable effects on the above parameters. CONCLUSION: Bosentan combined with amlodipine can offer similar renoprotective effects on that of cilazapril and may be a potent therapy to attenuate renal injury by reducing renal protein levels of TGF-beta1 in diabetes with a hypertensive state.展开更多
基金Supported by the U.S.National Institute of Alcohol Abuse and Alcoholism,R01 AA014428 and by the Robert E.and May R.Wright Foundation,No.263
文摘Deficiencies in vitamins or other factors(B6,B12,folic acid, betaine)and genetic disorders for the metabolism of the non-protein amino acid-homocysteine(Hcy)lead to hyperhomocysteinemia(HHcy).HHcy is an integral component of several disorders including cardiovascular disease,neurodegeneration,diabetes and alcoholic liver disease.HHcy unleashes mediators of inflammation such as NFκB,IL-1β,IL-6,and IL-8,increases production of intracellular superoxide anion causing oxidative stress and reducing intracellular level of nitric oxide(NO),and induces endoplasrnic reticulum(ER)stress which can explain many processes of Hcy-promoted cell injury such as apoptosis, fat accumulation,and inflammation.Animal models have played an important role in determining the biological effects of HHcy.ER stress may also be involved in other liver diseases such as α_1-antitrypsin(α_1-AT)deficiency and hepatitis C and/or B virus infection.Future research should evaluate the possible potentiative effects of alcohol and hepatic virus infection on ER stress-induced liver injury,study potentially beneficial effects of lowering Hcy and preventing ER stress in alcoholic humans,and examine polymorphisrn of Hcy metabolizing enzymes as potential risk-factors for the development of HHcy and liver disease.
基金ThisresearchworkwassupportedbyMinistryofPublicHealthandShanghaiBairenProjectFoundation (No .98BR0 3 8)
文摘OBJECTIVE: To investigate the effects of the mixed endothelin receptor antagonist, bosentan, combined with the long-acting calcium channel blocker, amlodipine, compared to the angiotensin-converting enzyme inhibitor, cilazapril, on the progressive renal injury in spontaneous hypertensive rats (SHR) with diabetes. METHODS: Diabetic hypertensive rats (SHR-DM) were induced by streptozotozin injected in male SHR (7-week-old),and divided into an untreated and three treated groups: 1) cilazapril treated group; 2) bosentan+amlodipine treated group; and 3) amlodipine treated group. Wistar Kyoto rats (WKY) and SHR rats served as normotensive and hypertensive control, respectively. The mean arterial blood pressure, renal function, endothelin and angiotensin II levels as well as the protein expression of renal extracellular matrix components and transforming growth factor (TGF)-beta1 were determined at the end of the 4th week. RESULTS: Mean arterial blood pressure significantly increased in SHR and SHR-DM rats compared to WKY rats. All the therapies reduced the blood pressure to normal levels. However, the enhanced urinary protein excretion, the decreased creatinine clearance as well as the increased plasma and intrarenal endothelin and angiotens in II levels were found in the untreated SHR-DM and prevented by treatment with bosentan+amlodipine and cilazapril. Similarly, these two kinds of therapies in SHR-DM abolished the overexpression of renal TGF-beta1 by Western blot analysis and reduced the accumulation of collagen type IV, laminin and fibronectin proteins by an immunochemical approach. Amlodipine monotherapy had no detectable effects on the above parameters. CONCLUSION: Bosentan combined with amlodipine can offer similar renoprotective effects on that of cilazapril and may be a potent therapy to attenuate renal injury by reducing renal protein levels of TGF-beta1 in diabetes with a hypertensive state.
