Moderate exercise training reduces kidney oxidative stress and mortality of hypertensive diabetic rats

Abstract

Hypertension plays a negative role on the development of diabetic nephropathy, increasing the mortality of patients. Moderate exercise training decreases oxidative stress and is a therapy for cardiovascular and metabolic diseases. The aim was to determine the effect of exercise on renal oxidative stress and mortality of spontaneous hypertensive diabetic rats (SHR + streptozotocin 50mg/Kg; 3 months old) randomized into: sedentary (S, n=8) and trained (T, n=8) groups. After moderate exercise training (treadmill ‐ 1h/day, 5days/wk, 10wk), kidney was excised for measurement of oxidative damage (lipoperoxidation–LPO) and antioxidant enzymes activity (superoxide dismutase–SOD, catalase–CAT, and glutathione peroxidase–GPX activity) (Student's t‐test; Kaplan‐Meier method). T group presented lower renal LPO (T=1199± 184; S=2549± 111 counts/second/mg protein), higher renal antioxidant enzymes activity (SOD:T=10.6± 0.7; S=8.3± 0.4 U/mg protein; CAT:T=23722; S=164± 17 pmol/mg protein; GPX:T=7.8± 0.3; S=6.4± 0.5 nmol/min/mg protein; p<0.05) and lower mortality (p=0.03). Our results show that moderate exercise training reduces oxidative stress and suggests that this adaptation may decrease mortality of hypertensive diabetic animals. Financial Support: FAPESP, CNPq.

Catecholamines production by kidney tissue and mesangial cell culture is differentially modulated by diabetes

“…On the other hand, they present histological changes, including glomeruli and the tubulointerstitial lesions, only after 3-6 months of diabetes. This is in accordance with a previous study from our group, using the same animal model, where Ronchi et al (2007) 13 did not find any structural alteration analyzing kidney histology of diabetic animals during the early development of the disease 21 , 22 . This is also supported by other studies, showing that STZ-animals can be resistant to the development of histological kidney damage 23 .…”