Black Lucques olives prevented bone loss caused by ovariectomy and talc granulomatosis in rats

Abstract
This study was conducted to determine whether olive fruits, rich in micronutrients, might improve bone loss in ovariectomized (OVX) rats (an experimental model of postmenopausal osteoporosis) and in OVX rats with granulomatosis inflammation (a model of senile osteoporosis). Six-month-old Wistar female rats underwent ovariectomy and were then immediately treated orally by substituting oil in the diet by 10 g/d green Lucques olives or 6 g/d black Lucques olives for each rat for 84 days. OVX rats and sham-operated controls received the same diet with oil. Three weeks before the end of the experiment, subcutaneous inflammation was provoked by injections of sterile magnesium silicate in half the animals in each group. In OVX rats, granulomatosis inflammation, characterized by a rise in inflammatory parameters such as fibrinogen, α1-acid glycoprotein, spleen weight and granulocyte level, and an impairment of oxidative status (as shown by a decrease in plasma antioxidant capacity, a higher rate of isoprostane excretion) elicited a bone loss in the whole femur and in the metaphyseal areas considered on their own. Whereas green olives had no effect on osteopenia, consumption of the black variety prevented bone loss in the whole femur and at cortical sites in those oestrogen-deficient animals with talc inflammation (diaphyseal bone mineral density: black olives and inflammation 0·2323 (se 0·0026) v. ovariectomy and inflammation 0·2117 (se 0·0030); P = 0·027). This bone-sparing effect seemed to result from an improvement in the inflammatory and oxidative status. The present data show that black olives are able to prevent bone loss in an experimental model of senile osteoporosis (oestrogen-deficient rats in which a low-grade inflammation was induced by talc injection).