RESUMO
INTRODUCTION: In large dosages, acetaminophen (APAP) produces acute kidney necrosis in most mammalian species. High neopterin levels have been accepted as strong indicators for the clinical severity of some diseases. In this study, we aimed to evaluate whether neopterin is a biomarker in the identification of APAP-induced nephrotoxicity. MATERIALS AND METHODS: Thirty adult male Wistar rats were randomly divided into three groups: control, APAP-1, and APAP-2 groups. APAP-1 and APAP-2 group rats were given a single dose of 1 and 2 g/kg body weight of APAP by gastric tube, respectively. Kidney tissues and blood samples were obtained for biochemical and histopathological analyses. Biochemical parameters, serum and kidney neopterin levels, and the grade of tubular injury were compared in the control, APAP-1, and APAP-2 group animals. RESULTS: APAP treatments caused tubular necrosis in the kidney and increase in serum creatinine concentrations accompanied by elevated serum and kidney neopterin levels. In the rats of groups APAP-1 and APAP-2 when compared with that of the control group (109.1 pmol/mg protein), median kidney neopterin concentrations were 162.1 (p = 0.089) and 222.2 (p < 0.001) pmol/mg protein, respectively. The grade of tubular injury of the APAP-1 and APAP-2 groups was higher than the group of control (both p < 0.001). CONCLUSIONS: Serum and kidney neopterin levels could be sensible alternative to evaluate the risk to have nephrotoxicity because of APAP overdose. The elevated serum and kidney neopterin in the APAP-induced tubular necrosis might be a marker of acute histological kidney injury.