Effect of Aerobic Exercise on the Renal Apelin andNitric Oxide Levels in Male Rats Exposed toNano Zinc Oxide

Nanoparticles accumulate easily in the organs of the body due to their small size. Therefore, an increase in the use of nanoparticles leads to more concerns about their side effects. Accordingly, the present study was conducted to investigate the effect of aerobic exercise on the renal Apelin and Nitric Oxide (NO) levels in male rats exposed to zinc oxide nanoparticles.

In this experimental study, 35 male Wistar rats with a weight range of 150-170 g were randomly divided into five groups of seven animals per group. The groups included control, salin, zinc oxide nano, exercise, and exercise+zinc oxide nano. The zinc oxide nano (1mg/kg) was administered intraperitoneally 5 times/week to the exercise and exercise+zinc oxide nano groups. The exercise program consisted of progressive running on a treadmill (speed from 15 to 18 m/min, 25 to 44 min/day, five times per week for four weeks). The rats were euthanized two days after the last intervention. The kidney tissues were removed and homogenized to measure the levels of Apelin, NO, and Malondialdehyde (MDA). The data were analyzed through a one-way ANOVA test (P<0.05).

The results indicated that the zinc oxide nano administration significantly increased renal MDA as well as NO and significantly decreased Apelin, compared to the control group. Moreover, the 4-week exercise training was associated with a significant decrease in the renal MDA in exercise and exercise+zinc oxide nano groups and a significant increase in Apelin levels in the exercise group. Exercise also induced a significant increase in the tissue NO levels in the healthy rats; however, it reduced NO level in the kidney of rats exposed to zinc oxide nano.

It seems that regular exercise can exert its protective role against zinc oxide nanoparticle-induced renal injury by reducing oxidative stress, increasing Apelin, and modifying NO levels in the kidney tissue.