Therapeutic action of physical exercise on markers of oxidative stress induced by chronic kidney disease Priscila Soares de Souza, Luis Gustavo Costa da Rocha, Camila Baumer Tromm, Débora Luz Scheffer, Eduardo Ghisi Victor, Paulo Cesar Lock da Silveira, Claudio Teodoro de Souza, Luciano Acordi Silva, Ricardo Aurino Pinho ⁎ Laboratory of Exercise Biochemistry and Physiology, Postgraduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, 88806000, Criciúma, SC, Brazil abstract article info Article history: Received 8 September 2011 Accepted 22 June 2012 Keywords: Chronic kidney disease Physical exercise Oxidative stress Rehabilitation Aims: To investigate the effects physical training exerts on markers of oxidative stress in rats with chronic kidney disease (CKD). Main methods: Twenty-four male Wistar rats were divided into four groups (n=6): sham, CKD, exercise-sham and exercise-CKD. Surgical reduction of the renal mass was performed (5/6 nephrectomized) and exercise was conducted on a treadmill (50 min/day up to 1 km/h for, 5 days/week for eight weeks). Forty-eight hours after the last exercise session, blood (1 mL) was collected from the abdominal aorta and animals were decapitated. The left kidney was surgically removed and stored at -70 °C for subsequent analysis. Key findings: An increase was observed in creatinine and urea levels, superoxide production, antioxidant en- zymes, and oxidative damage in the CKD group, as compared to sham animals (pb 0.05). Physical training made superoxide production and oxidative damage decrease in the CKD group (p b 0.05), increasing SOD and GPX activity, though it did not increase the antioxidant effects of CAT, and renal parameters. Significance: Even without altering renal function in animals induced to CKD model, the results show that phys- ical training is an important component in the treatment of CKD, because it exerted a positive influence on ox- idative stress parameters, especially on the reduction in superoxide production and oxidative damage, as well as an improvement in the antioxidant defense system, like SOD and GPX. © 2012 Elsevier Inc. All rights reserved. Introduction Chronic kidney disease (CKD) is characterized by progressive loss of nephrons caused by increased intraglomerular pressure and hyperfiltration. CKD is associated with a high prevalence of several other diseases, and has become a worldwide health issue due to the high economic costs involved in CKD diagnosis and treatment (Yamashita et al., 2008). Previous studies have associated CKD with oxidative stress. Exper- imental evidence has shown that reactive oxygen species (ROS) play a key role in the pathophysiological pathways of a wide variety of clinical and experimental renal diseases (Vaziri, 2004; Johansen, 2005; Lim et al., 2002; Rutkowski et al., 2006; Crowel et al., 2007; Shah et al., 2007; Coelho et al., 2010). Pro-oxidant stimuli are a result of the effects of uremic toxins, an- giotensin 2, proinflammatory cytokines, blood–dialyzer interaction, reaction to catheters and arteriovenous grafts, iron overload, chronic infections, and underlying immunological or metabolic disorders, such as diabetes (Vaziri, 2004). Routine therapeutic interventions, especially pharmacological and hemodialysis treatments, are able to significantly mitigate the severity of CKD; in addition, physical training also can be an important compo- nent in the treatment of CKD (Johansen, 2005). According to Pechter (2003) and Moinuddin and Leehey (2008), exercise conditioning has been shown to have a positive influence on physical capacity, hyperten- sion, left ventricular function, lipid and glucose metabolism, oxidative status, anemia, and quality of life in CKD patients and patients on renal replacement therapy. A recent study conducted in our laboratory (Coelho et al., 2010) has shown that physical training performed before the onset of renal lesion is capable of improving oxidative stress param- eters, possibly by reducing oxidant production without altering renal function and the antioxidant defense system. Although the biochemical basis of CKD complications has been ex- tensively studied, the pathogenesis of kidney disease in molecular/ biochemical terms and the relation with physical exercise has yet to be fully elucidated. In this sense, the aim this study was to observe the effects of physical training after renal lesion on oxidative stress parameters in animals exposed to CKD. Life Sciences 91 (2012) 132–136 ⁎ Corresponding author at: Laboratory of Exercise Biochemistry and Physiology, Postgraduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, 88806‐000 Criciúma, SC, Brazil. Tel.: +55 48 3431 2773; fax: +55 48 3431–2773. E-mail address: pinho@unesc.net (R.A. Pinho). 0024-3205/$ – see front matter © 2012 Elsevier Inc. All rights reserved. doi:10.1016/j.lfs.2012.06.028 Contents lists available at SciVerse ScienceDirect Life Sciences journal homepage: www.elsevier.com/locate/lifescie