Effects of Aerobic Training and Curcumin Supplementation on Cardiomyocyte Apoptosis and MiRNAs Expression in Rats Exposed to Arsenic

The aim of this study was to investigate the effects of HIIT and curcumin supplementation on cardiac tissue caspase 3 content and also expression of miR-1 and miR-133 in rats exposed to arsenic. Forty-eight (age: 16 weeks, weight: 340.31 ± 24.77 gr) male rats were randomized into six groups including on Arsenic-Training (HIIT), Arsenic-Curcumin (Curcumin), Arsenic – Training + Curcumin (Concomitant), Arsenic (Arsenic), Ethanol Control and Normal Control (pure water). Arsenic 5 mg/bw.day and Curcumin 15 mg/bw.day were consumed orally for six weeks. HIIT were conducted for six weeks (5 d/w) including on 60 min interval running/session (each interval bout was consisted of 4 min running at 85-90% of v Vo2max with 2 min recovery between work intervals at 50-60% of v Vo2max). Cardiac Caspase 3 and miRNAs expression levels were evaluated by western blot and RT-PCR analysis methods respectively. Cardiac mir-1 expression level (P=0.001) and also caspase 3 content (P=0.001) were higher, however; mir-133 expression level was lower (P=0.001) in the Arsenic group than the Normal Control. While no differences were observed in miR-1(P=0.20) and miR-133 (P=0.45) expressions as well as caspase 3 content (P=0.26) between the HIIT and Arsenic groups; lower caspase 3 content was observed in Curcumin group than the Arsenic counterparts (P=0.001). However, in Concomitant group, there were a lower mir-1 expression (P=0.042) and caspase 3 content (P=0.001) in accompany with a higher mir-133 (P=0.010) expression compared to the Arsenic group. Arsenic exposure predisposes cardiomyocytes to apoptosis via modifications in both miR-1 and miR-133 expressions which is associated with cardiac diseases. While physical training could not fully overcome arsenic toxicity in cardiomyocytes, curcumin supplementation and mostly the concomitant effect have more benefits. However, more research warranted to be done because of the lack of similar evidence and also limitations in this study.