Effects of nano-hydroxyapatite/chitosan (N-HA/CS) on MC3T3-E1 cell and metabolie organ in SD rats

Composite conmposed of nano-hydroxyapatite and chitosan (n-HA/CS) is widely used in the field of bone repair and alternative. To investigate the degradation effects of n-HA/CS on metabolism organs in SD rat and analyze the possible mechanism, particulate n-HA/CS was prepared by precipitation and characterized by IR and XRD. Serum biochemical parameters measurement and histopathological analysis were performed to evaluate the composite toxicity after 8 weeks of composite implantation (100 mg/kg). Results show that blood urea nitrogen (BUN) levels was 29.6 mmol/L, creatinine (CR) levels was 66.9 umol/L, total bilirubin (T-B) and indirect bilirubin (I-B) levels were also increased to 1.79 umol/L and 1.32umol/L. Compared with that of control, there were significant differences (P ≤ 0.05). A large number of apoptotic instead of necrosis cells were observed in the liver and renal proximal tubule tissue. It is concluded that the toxicity of n-HA/CS is attributable to the cells apoptosis.