Effects of low molecular weight chitosans on aristolochic acid-induced renal lesions in mice

This study investigated the effects of low molecular weight chitosan (LMWC) on the renal functions for aristolochic acid (AA)-induced renal lesions in C3H/He mice. Commercial crab shell chitosan (molecular mass of ∼1100 kDa) was hydrolysed using bamboo chitosanase at pH 3.5 and 50 °C for 18 h. LMWC (with molecular mass of ∼29 kDa) was isolated from the hydrolysate through 50% methanol fractionation. The levels of urinary microalbumin, urinary-N-acetyl-beta-d-glucosaminidase, serum creatinine, and blood urea nitrogen were higher in the AA induced mice than those in the control group, while the rate for creatinine clearance was lower in the AA induced mice. Oral administration of LMWC could suppress the elevation of urinary and blood nitrogen concentrations induced by AA treatment. Renal histopathological examination revealed that AA-induced renal alterations were reverted effectively by the treatment of LMWC at three tested doses, especially at the moderate dose of 500 mg/kg BW.