Ozone Therapy on Rats Submitted to Subtotal Nephrectomy: Role of Antioxidant System

Chronic renal failure (CRF) represents a world health problem. Ozone increases the endogenous antioxidant defense system, preserving the cell redox state. The aim of this study is to evaluate the effect of ozone/oxygen mixture in the renal function, morphology, and biochemical parameters, in an experimental model of CRF (subtotal nephrectomy). Ozone/oxygen mixture was applied daily, by rectal insufflation (0.5 mg/kg) for 15 sessions after the nephrectomy. Renal function was evaluated, as well as different biochemical parameters, at the beginning and at the end of the study (10 weeks). Renal plasmatic flow (RPF), glomerular filtration rate (GFR), the urine excretion index, and the sodium and potassium excretions (as a measurement of tubular function) in the ozone group were similar to those in Sham group. Nevertheless, nephrectomized rats without ozone (positive control group) showed the lowest RPF, GFR, and urine excretion figures, as well as tubular function. Animals treated with ozone showed systolic arterial pressure (SAP) figures lower than those in the positive control group, but higher values compared to Sham group. Serum creatinine values and protein excretion in 24 hours in the ozone group were decreased compared with nephrectomized rats, but were still higher than normal values. Histological study demonstrated that animals treated with ozone showed less number of lesions in comparison with nephrectomized rats. Thiobarbituric acid reactive substances were significantly increased in nephrectomized and ozone-treated nephrectomized rats in comparison with Sham group. In the positive control group, superoxide dismutase (SOD) and catalase (CAT) showed the lowest figures in comparison with the other groups. However, ozone/oxygen mixture induced a significant stimulation in the enzymatic activity of CAT, SOD, and glutathione peroxidase, as well as reduced glutathione in relation with Sham and positive control groups. In this animal model of CRF, ozone rectal administrations produced a delay in the advance of the disease, protecting the kidneys against vascular, hemorheological, and oxidative mechanisms. This behavior suggests ozone therapy has a protective effect on renal tissue by downregulation of the oxidative stress shown in CRF

PAPEL NEFROPROTECTOR DEL OZONO EN EL DAÑO RENAL CRÓNICO EXPERIMENTAL

Los productos avanzados de la glicosilación de proteínas (PAGP) constituyen mediadores importantes que ocasionan daño al tejido renal en diferentes situaciones clínicas. Conociendo los efectos nefroprotectores de la ozonoterapia rectal (OTR), el objetivo del estudio fue demostrar la influencia de esta terapia en los niveles de fructosamina como PAGP y la actividad de la fosfolipasa A2 en tejido renal con insuficiencia renal crónica por ablación de la masa renal (AMR) en ratas. Se seleccionaron ratas Wistar hembra con peso corporal entre 200 y 220 g, se dividieron en cuatro grupos experimentales: un grupo control sin daño renal, otro grupo control con daño renal por AMR y otros dos grupos también con daño renal y tratados con ozonoterapia y oxígeno también por vía rectal, respectivamente. Los resultados evidenciaron la reducción significativa p< 0,05 de los niveles de fructosamina y la actividad de la fosfolipasa A2 en el tejido renal de ratas tratadas con OTR.  Por lo que se concluye que la OTR demostró acción antinflamatoria, como mecanismo contribuyente a la preservación de la estructura y función del riñón sometido a daño renal experimental crónico, por ablación de la masa rena