Reduced collagen accumulation and augmented MMP-2 activity in left ventricle of old rats submitted to high-intensity resistance training. Academic Article uri icon

abstract

  • Progressive fibrosis is a hallmark of the aging heart. Age-related fibrosis is modulated by endurance exercise training; however, little is known concerning the influence of resistance training (RT). Therefore we investigated the chronic effects of high-intensity RT on age-associated alterations of left ventricle (LV) structure, collagen content, matrix metalloproteinase-2 (MMP-2), and extracellular matrix-related gene expression, including transforming growth factor- (TGF-). Young adult (3 mo) and aged (21 mo) male Wistar rats were submitted to a RT protocol (ladder climbing with 65, 85, 95, and 100% load), three times a week for 12 wk. Forty-eight hours posttraining, arterial systolic and diastolic pressure, LV end-diastolic pressure (LVEDP) and dP/dt were recorded. LV morphology, collagen deposition, and gene expression of type I (COL-I) and type III (COL-III) collagen, MMP-2, tissue inhibitor of metalloproteinases-1 (TIMP-1), and TGF-1 were analyzed by quantitative reverse transcriptase-PCR. MMP-2 content was assessed by zymography. Increased collagen deposition was observed in LV from aged rats. These parameters were modulated by RT and were associated with increased MMP-2 activity and decreased COL-I, TGF-1, and TIMP-1 mRNA content. Despite the effect of RT on collagen accumulation, there was no improvement on LVEDP and maximal negative LV dP/dt of aged rats. Cardiomyocyte diameter was preserved in all experimental conditions. In conclusion, RT attenuated age-associated collagen accumulation, concomitant to the increase in MMP-2 activity and decreased expression of COL-I, TGF-1, and TIMP-1 in LV, illustrating a cardioprotective effect of RT on ventricular structure and function.NEW & NOTEWORTHY We demonstrated the beneficial resistance-training effect against age-related left ventricle collagen accumulation in the left ventricle, which was associated with decreased type I collagen (COL-I), transforming growth factor-1 (TGF-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1) gene expression and matrix metalloproteinase-2 (MMP-2) activity. Our findings suggest for the first time the potential effects of resistance training in modulating collagen accumulation and possibly fibrosis in the aging heart.

published proceedings

  • J Appl Physiol (1985)

author list (cited authors)

  • Guzzoni, V., Marqueti, R., Durigan, J., Faustino de Carvalho, H., Lino, R., Mekaro, M. S., ... Selistre-de-Arajo, H. S.

complete list of authors

  • Guzzoni, Vinicius||Marqueti, Rita de Cássia||Durigan, João Luíz Quagliotti||Faustino de Carvalho, Hernandes||Lino, Rafael Luis Bressani||Mekaro, Marcelo S||Costa Santos, Tayná Oliveira||Mecawi, André Souza||Rodrigues, José Antunes||Hord, Jeffrey M||Lawler, Jonh M||Davel, Ana Paula||Selistre-de-Araújo, Heloísa Sobreiro

publication date

  • January 1, 2017 11:11 AM