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

Author(s):Show less -

Guzzoni, Vinicius ^[1] ; Marqueti, Rita de Cassia ^[2] ; Quagliotti Durigan, Joao Luiz ^[2] ; de Carvalho, Hernandes Faustino ^[3] ; Bressani Lino, Rafael Luis ^[1] ; Mekaro, Marcelo S. ^[1] ; Costa Santos, Tayna Oliveira ^[1] ; Mecawi, Andre Souza ^[4] ; Rodrigues, Jose Antunes ^[4] ; Hord, Jeffrey M. ^[5] ; Lawler, Jonh M. ^[5] ; Davel, Ana Paula ^[3] ; Selistre-de-Araujo, Heloisa Sobreiro ^[1]

Affiliation

^[1] Univ Fed Sao Carlos, Dept Physiol Sci, Sao Carlos, SP - Brazil

^[2] Univ Brasilia, Physiotherapy Div, Brasilia, DF - Brazil

^[3] Univ Estadual Campinas, Inst Biol, Campinas, SP - Brazil

^[4] Univ Sao Paulo, Sch Med Ribeirao Preto, Dept Physiol, Sao Paulo - Brazil

^[5] Texas A&M Univ, Dept Hlth & Kinesiol, College Stn, TX - USA

• Document type: Journal article
• Source: Journal of Applied Physiology; v. 123, n. 3, p. 655-663, SEP 2017.
• Web of Science Citations: 4

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-beta (TGF-beta). 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-beta 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-beta 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-beta 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-beta 1 (TGF-beta 1), and tissue inhibitor of metalloproteinases-1 (TIMP-1) gene expression and matrix metalloproteinase-2 (MMP-2) activity. Our findings sug-gest for the first time the potential effects of resistance training in modulating collagen accumulation and possibly fibrosis in the aging heart. (AU)

• FAPESP's process: 13/00798-2 - The extracellular matrix in aging, exercise and in the tumor microenvironment
• Grantee: Heloisa Sobreiro Selistre de Araújo
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/50938-8 - INCT 2014: in Photonics Applied to Cell Biology
• Grantee: Hernandes Faustino de Carvalho
• Support Opportunities: Research Projects - Thematic Grants