Histopathological and immunohistochemical evaluation of antioxidant effect of Aloevera whole leaf extract on fluoride induced bone toxicity in growing rats

The aim of this study was to investigate the histopathological and immunohistochemical changes in sodium fluoride induced bone toxicity of growing rats and its amelioration with Aloevera whole leaf extract. The present study was carried using 72 male Wistar albino rats that were randomly divided into four groups consisting of 18 rats in each. Sodium fluoride was gavaged orally using water as vehicle @ 18mg NaF/kg body weight to groups II and Aloevera @ 200 mg/kg body wt. in distilled water was given along with sodium fluoride to group IV for 45 days. Group I and III were kept as controls and treated with distilled water and Aloevera, respectively. Six rats from each group were sacrificed at fortnight interval. Bones (humerus and femur) were collected and preserved in 10% neutral buffered formalin for histopathological and immunohistochemical studies. Histopathologically, bones revealed a decrease in matrix volume and cartilage septae thickness, an increase in the number and diameter of chondrocytes on growth plate and the epiphyseal ossification center, irregular lamellae, mild increase in osteoblast number and irregular, thin and atrophied trabeculae, loss in continuity of growth plate, atrophied growth plate and irregular haversian canals in most of the group II rats. All these changes were mild in Aloevera ameliorated rats (Group IV). Immunohistochemically, increased expression of osteonectin was observed in osteoid of epiphysis particularly around osteoblasts and inside the growing chondrocytes, which were more conspicuous in NaF treated rats when compared to control and ameliorated group.