Histological and morphometric studies on the effect of alpha-lipoic acid on postovariectomy osteoporosis induced in adult female albino rats

Introduction: An imbalance between bone formation and bone resorption underlined the pathogenesis of reduced bone mass in osteoporosis associated with menopause.Aim of the study: To investigate whether α-lipoic acid can have any therapeutic application in treating bone loss in ovariectomized osteoporotic rats.Materials and methods: Twenty-four adult female rats were divided into four groups: a sham-operated control group (group 1), a nontreated ovariectomized group (group 2), an α-lipoic acid-treated ovariectomized group (group 3), and a sham-operated α-lipoic acid-treated group (group 4). Histological decalcified and undecalcified distal femur specimens were prepared and histomorphometric parameters of bone resortion and bone formation were carried out.Results: Assessment of bone resorption parameters of the distal femur metaphysis and diaphysis showed that ovariectomy in group 2 produced significant increase in mean resorption surface percentage, 28% loss in mean cortical bone thickness, and 48% loss in mean trabecular bone volume compared with controls. However, α-lipoic acid administration to ovariectomized rats reduced the mean resorption surface percentage to control levels. Moreover, evaluation of bone formation parameters showed that both ovariectomy in group 2 and α-lipoic acid administration to ovariectomized rats of group 3 caused significant increase in mean osteoid thickness and in mean osteoid surface percentage relative to control rats. Alpha-lipoic acid also completely (100%) restored mean cortical bone thickness, restored 90% of mean trabecular bone volume, and ameliorated the osteoporotic changes that accompanied ovariectomy.Conclusion and recommendation: Alpha-lipoic acid improved the imbalance between bone resorption and bone formation, and therefore it is recommended to treat osteoporosis with α-lipoic acid