Calpain-2 Compensation Promotes Angiotensin II-Induced Ascending and Abdominal Aortic Aneurysms in Calpain-1 Deficient Mice
Year: 2013
Type: article
Abstract: BACKGROUND AND OBJECTIVE: Recently, we demonstrated that angiotensin II (AngII)-infusion profoundly increased both aortic protein and activity of calpains, calcium-activated cysteine proteases, in mice. In addition, pharmacological inhibition of calpain attenuated AngII-induced abdominal aortic aneurysm (AA) in mice. Recent studies have shown that AngII infusion into mice leads to aneurysmal formation localized to the ascending aorta. However, the precise functional contribution of calpain isoforms (-1 or -2) in AngII-induced abdominal AA formation is not known. Similarly, a functional role of calpain in AngII-induced ascending AA remains to be defined. Using BDA-410, an inhibitor of calpains, and calpain-1 genetic deficient mice, we examined the relative contribution of calpain isoforms in AngII-induced ascending and abdominal AA development. METHODOLOGY/RESULTS: To investigate the relative contribution of calpain-1 and -2 in development of AngII-induced AAs, male LDLr -/- mice that were either calpain-1 +/+ or -/- were fed a saturated fat-enriched diet and infused with AngII (1,000 ng/kg/min) for 4 weeks. Calpain-1 deficiency had no significant effect on body weight or blood pressure during AngII infusion. Moreover, calpain-1 deficiency showed no discernible effects on AngII-induced ascending and abdominal AAs. Interestingly, AngII infusion induced increased expression of calpain-2 protein, thus compensating for total calpain activity in aortas of calpain-1 deficient mice. Oral administration of BDA-410, a calpain inhibitor, along with AngII-infusion significantly attenuated AngII-induced ascending and abdominal AA formation in both calpain-1 +/+ and -/- mice as compared to vehicle administered mice. Furthermore, BDA-410 administration attenuated AngII-induced aortic medial hypertrophy and macrophage accumulation. Western blot and immunostaining analyses revealed BDA-410 administration attenuated AngII-induced C-terminal fragmentation of filamin A, an actin binding cytoskeletal protein in aorta. CONCLUSION: Calpain-2 compensates for loss of calpain-1, and both calpain isoforms are involved in AngII-induced aortic aneurysm formation in mice.
Source: PLoS ONE
Institutions: University of Kentucky, Tufts University, Okayama University
Language: English
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,382
Funders: American Heart Association, Mitsubishi Tanabe Pharma Corporation, National Institutes of Health, Japan Society for the Promotion of Science, National Heart, Lung, and Blood Institute, National Institute of General Medical Sciences, National Institute of Diabetes and Digestive and Kidney Diseases, National Center for Research Resources
Awards: Calpain-1 Signaling Pathways in Platelets, G2053556709, Center of Research in Obesity and Cardiovascular Disease (1P20 RR021954-01A1), Center of Research on Obesity and Cardiovascular Diseases, The role of calpain on the development of abdominal aortic aneurysm, Mechanisms of abdominal aortic aneurysm formation, G730305367, G9000058396, Diabetes Research Center
OpenAlex ID: W2025048033