Noa M, Más R, Mendoza S, Gámez R, Mendoza N
Center for Natural Products, National Center for Scientific Research, Havana City, Cuba.
Drugs Exp Clin Res. 2004;30(1):35-41.
Bisphosphonates inhibit bone resorption through mechanisms involving the metabolic pathway from mevalonate to cholesterol. Mevalonate is a precursor of the lipoids required for osteoclast activity and thus inhibition of its synthesis affects bone metabolism. Inhibitors of hydroxymethylglutaryl CoA (HMGCoA) reductase might increase experimentally new bone formation through a mevalonate-dependent effect. D-003 is a mixture of high molecular weight fatty acids isolated from sugar cane wax, which inhibits cholesterol biosynthesis through indirect regulation of HMGCoA reductase activity. This study was undertaken to determine whether D-003 could prevent bone loss in ovariectomized rats. Sprague Dawley female rats were ovariectomized or sham operated and were randomly distributed into five groups: a control ovariectomized and a sham (false-operated) group receiving Tween/H2O vehicle, a group treated with alendronate (3 mg/kg/day) and two groups treated with D-003 (50 and 200 mg/kg/day). Treatments were administered for 3 months. At sacrifice, bones were removed and histological variables of bone resorption and formation were studied by histomorphometry. Ovariectomy diminished trabecular number and thickness and increased trabecular gap, osteoclast number and surface. Alendronate and D-003 prevented a decrease in trabecular number and thickness as well as increases in trabecular separation, osteoclast number and surface compared with ovariectomized controls, thus preventing the bone loss and decreased bone resorption induced by ovariectomy, but failed to increase osteoblast surface compared with control ovariectomized rats. In conclusion, D-003 (50 and 200 mg/kg/day) prevented bone loss and decreased bone resorption in ovariectomized rats, which suggests that this substance could be promising in preventing or treating osteoporosis.
双膦酸盐通过涉及从甲羟戊酸到胆固醇的代谢途径的机制抑制骨吸收。甲羟戊酸是破骨细胞活性所需类脂的前体,因此抑制其合成会影响骨代谢。羟甲基戊二酰辅酶A(HMGCoA)还原酶抑制剂可能通过甲羟戊酸依赖性效应在实验中增加新骨形成。D - 003是从甘蔗蜡中分离出的高分子量脂肪酸混合物,它通过间接调节HMGCoA还原酶活性来抑制胆固醇生物合成。本研究旨在确定D - 003是否能预防去卵巢大鼠的骨质流失。将Sprague Dawley雌性大鼠进行去卵巢手术或假手术,并随机分为五组:一组去卵巢对照组和一组假手术(假操作)组接受吐温/水载体,一组用阿仑膦酸钠(3毫克/千克/天)治疗,两组用D - 003(50和200毫克/千克/天)治疗。治疗持续3个月。处死时,取出骨骼,通过组织形态计量学研究骨吸收和形成的组织学变量。去卵巢减少了小梁数量和厚度,增加了小梁间隙、破骨细胞数量和表面。与去卵巢对照组相比,阿仑膦酸钠和D - 003预防了小梁数量和厚度的减少以及小梁间距、破骨细胞数量和表面的增加,从而预防了去卵巢诱导的骨质流失和骨吸收减少,但与去卵巢对照大鼠相比未能增加成骨细胞表面。总之,D - 003(50和200毫克/千克/天)预防了去卵巢大鼠的骨质流失并减少了骨吸收,这表明该物质在预防或治疗骨质疏松症方面可能很有前景。