Anabolic steroid- and exercise-induced cardiac stress protein (HSP72) in the rat

Abstract

The present study investigated the effects of exercise and anabolicandrogenic steroids on cardiac HSP72 expression. Male Wistar rats were divided into experimental groups: nandrolone exercise (NE, N = 6), control exercise (CE, N = 6), nandrolone sedentary (NS, N = 6), and control sedentary (CS, N = 6). Animals in the NE and NS groups received a weekly intramuscular injection (6.5 mg/kg of body weight) of nandrolone decanoate, while those in the CS and CE groups received mineral oil as vehicle. Animals in the NE and CE groups were submitted to a progressive running program on a treadmill, for 8 weeks. Fragments of the left ventricle were collected at sacrifice and the relative immunoblot contents of HSP72 were determined. Heart weight to body weight ratio was higher in exercised than in sedentary animals (P < 0.05, 4.65 ± 0.38 vs 4.20 ± 0.47 mg/g, respectively), independently of nandrolone, and in nandrolone-treated than untreated animals (P < 0.05, 4.68 ± 0.47 vs 4.18 ± 0.32 mg/g, respectively), independently of exercise. Cardiac HSP72 accumulation was higher in exercised than in sedentary animals (P < 0.05, 677.16 ± 129.14 vs 246.24 ± 46.30 relative unit, respectively), independently of nandrolone, but not different between nandrolone-treated and untreated animals (P > 0.05, 560.88 ± 127.53 vs 362.52 ± 95.97 relative unit, respectively) independently of exercise. Exercise-induced HSP72 expression was not affected by nandrolone. These levels of HSP72 expression in response to nandrolone administration suggest either a low intracellular stress or a possible less protection to the myocardium.

Doping and effects of anabolic androgenic steroids on the heart: histological, ultrastructural, and echocardiographic assessment in strength athletes

“…Each rat was injected with 10 mg/kg sustanon intramuscularly once a week (1/100 of LD50) for 8 weeks. 9 Tissue collection and preparation At the appropriate date of the experiment, animals were sacrificed under ether anesthesia. The heart specimens were taken from the anterior-lateral wall of the left ventricle near the apex.…”

Treinamento em natação com baixa intensidade não protege músculo esquelético contra lesões induzidas por exercício exaustivo em ratos

“…After the transference (in approximately one hour at 0.70 steady amperes), the nitrocellulose membrane was immersed in blocking solution (casein -Non-fat Dry Milk, Biorad) for one hour. Subsequently, they were washed four times for 15 hours under agitation. After the incubation period, the membrane was washed with TBS-T four times, for 15 minutes each and later incubated with the Anti-Mouse IgG antibody (alkaline phosphatase -SigmA), in 1:10.000 dilution, for approximately two hours.…”

“…There is evidence that the HSP70 may inhibit the cellular death both by the caspases-dependent way and by the caspases-independent way (12) . Regular moderate physical activity, on the other hand, is able to increase the antioxidant defense capacity of the body (13) , as well as to increase the Hsp72 expression, the inducible HSP70 form (14,15) . Thus, physical training has been associated with the organism's protection against stressing events (16)(17)(18) and attenuation of cellular death in cardiac and skeletal muscles (19,20) .…”

L-NAME Treatment Enhances Exercise-induced Content of Myocardial Heat Shock Protein 72 (Hsp72) in Rats

“…For Hsp72 and Hsp73 western blotting, LV samples were pulverized in liquid nitrogen using a mortar (Fisher Scientific, USA) and then homogenized in ice-cold buffer (600 mM NaCl, 15 mM Tris-HCl, 1 mM PMSF, pH 7.5) as previously described [27]. After 5 min on ice, homogenized tissues were centrifuged (14,000 g, 20 min, 4°C), and the protein concentration in the supernatant was determined using Bradford reagent (Bio-Rad, USA).…”