Acute kidney injury induced by glycerol is worsened by orchiectomy and attenuated by testosterone replacement

Abstract

Although several studies have demonstrated that the male gender represents an independent risk factor for renal disease, evidence shows that androgens exert renal protective actions. The findings are controversial and no studies have evaluated the effects of orchiectomy and testosterone replacement on glycerol-induced renal injury. Male Wistar rats were submitted to orchiectomy or sham surgery and divided into four groups: SC, sham control rats injected with NaCl; SG, sham rats injected with glycerol; OG, orchiectomized rats injected with glycerol; OGT, orchiectomized rats injected with glycerol and testosterone. Testosterone was administered daily for 14 days in the OGT group. After 11 days of testosterone replacement in the OGT group, SC rats were submitted to a saline injection, while SG, OG and OGT rats received glycerol. All rats were euthanized three days after injections. OG rats presented higher serum creatinine and urea, and sodium excretion, compared to SC and SG, while testosterone attenuated these changes. Acute tubular necrosis was also mitigated by testosterone. Renal immunostaining for macrophages, lymphocytes and NF-kappa B was higher in OG compared to SC and SG. In addition, renal interleukin-1 beta, Caspase 3 and AT1 gene expression was higher in OG rats compared to SG. Testosterone attenuated these alterations, except the NF-kappa B immunostaining. The renal NO was lower in OG rats compared to SG. Only the OG rats presented decreases in serum NO and renal HO-1, and increased TNF-alpha, angiotensinogen and AT1 expression compared to SC. We conclude that orchiectomy worsened glycerol-induced kidney injury, while testosterone attenuated this renal damage.