Change in kidney damage biomarkers after 13 weeks of exposing rats to the complex of Paecilomyces sinclairii and its host Bombyx mori larvae.

Complex of Paecilomyces sinclairii and host larvae, Bombyx mori, is a well known health food; however, concerns about nephrotoxicity have been raised. Kidney toxicity was investigated after 13 weeks of administering the complex orally to rats with parameters including blood urea nitrogen (BUN), creatinine, and kidney damage biomarkers, beta-2-microglobulin (ß2m), glutathione S-transferase alpha (GST-α), kidney injury molecule 1 (KIM-1), tissue inhibitor of matrix metalloproteinase 1 (TIMP-1), vascular endothelial growth factor (VEGF), calbindin, clusterin, cystatin C, neutrophil gelatinase-associated lipocalin (NGAL), and osteopontin. Dose-dependent kidney cell karyomegaly and tubular hypertrophy were observed, with higher severity in males. There was a dose-dependent increase in KIM-1 and TIMP-1 levels in kidney and urinary KIM-1, cystatin C, ß2m, and osteopontin levels. KIM-1 and TIMP-1 increased in male kidneys had not recovered by 2 weeks after stopping exposure. Cystatin C in kidney was significantly lowered in all treatment groups at 13 weeks of administration. All the changes were more noticeable in males. These data indicate that the complex damage renal tubule cells with histopathological lesions and changes in biomarker levels. Kidney and urinary KIM-1 and cystatin C were the most markedly affected and early increased indicators among biomarkers tested, whereas BUN and creatinine were not affected.

Kidney Toxicity Induced by 13 Weeks Exposure to the Fruiting Body of Paecilomyces sinclairii in Rats.

Paecilomyces sinclairiis (PS) is known as a functional food or human health supplement. However concerns have been raised about its kidney toxicity. This study was performed to investigate the kidney toxicity of PS by 13 week-oral administration to rats. Blood urea nitrogen (BUN), serum creatinine, and kidney damage biomarkers including beta-2-microglobulin (ß2m), glutathione S-transferase alpha (GST-α), kidney injury molecule 1 (KIM-1), tissue inhibitor of matrix metalloproteinase 1 (TIMP-1), vascular endothelial growth factor (VEGF), calbindin, clusterin, cystatin C, neutrophil gelatinase-associated lipocalin (NGAL) and osteopontin were measured during or after the treatment of PS. BUN, creatinine and kidney damage biomarkers in serum were not changed by PS. However, kidney cell karyomegaly and tubular hypertrophy were observed dose-dependently with higher severity in males. KIM-1, TIMP-1 and osteopontin in kidney and urine were increased dose dependently in male or at the highest dose in female rats. Increased urinary osteopontin by PS was not recovered at 2 weeks of post-exposure in both genders. Cystatin C in kidney was decreased at all treatment groups but inversely increased in urine. The changes in kidney damage biomarkers were more remarkable in male than female rats. These data indicate that the PS may provoke renal cell damage and glomerular filtration dysfunction in rats with histopathological lesions and change of kidney damage biomarkers in kidney or urine. Kidney and urinary KIM-1 and cystatin C were the most marked indicators, while kidney weight, BUN and creatinine and kidney damage biomarkers in serum were not influenced.