瘦素对成骨细胞及骨形成的影响

Effects of leptin on osteoblast and bone formation

目的:瘦素是近年来发现的具有调节食欲及能量消耗功能多肽激素。目前认为瘦素作用不仅限于中枢神经系统,其对骨代谢的调节作用,特别是对成骨细胞和骨形成的直接作用已越来越明确,深入研究其机制将为防治人类骨质疏松症等骨代谢疾病提供新途径。资料来源:应用网络检索自1994年瘦素基因发现以来Pubmed数据库相关文章,检索词“leptin,bone,boneformation,osteoblast”,限定文章语言种类为English。同时检索中国期刊全文数据库、万方数据、中国医院知识仓库CHKD期刊全文库相关文章,检索词“瘦素、骨、骨形成、成骨细胞”,限定文章语言种类为中文。资料选择:对资料进行初审,选取符合研究要求的有关文章查找全文。纳入标准:①瘦素受体及在成骨细胞表达的研究。②瘦素与体外培养成骨细胞增殖和分化的研究。③瘦素对体内骨形成的影响的研究。排除标准:重复研究。资料提炼:共收集到447篇有关瘦素与骨相关的文章,其中与骨形成和成骨细胞相关文章分别为112篇和85篇。排除重复或类似的同一研究,选择其中有代表性的18篇进行总结。资料综合:①瘦素受体表达于小鼠、大鼠、人成骨细胞、成骨细胞系ROS17/2.8、以及人骨髓间充质干细胞分化来源的成骨细胞中。②在体外培养细胞中,瘦素促进人原代成骨细胞增殖,同时,瘦素促进成骨细胞分化,其作用机制不同于骨形态发生蛋白2。③体内研究显示:循环瘦素水平与骨密度呈正相关关系;外源性瘦素替代治疗增加骨量;瘦素具有通过中枢神经系统调节骨形成的功能。结论:成骨细胞表达瘦素受体,是瘦素作用的直接靶点。瘦素通过外周和中枢途径作用于成骨细胞和骨形成。

OBJECTIVE： Leptin is a newly discovered polypeptide hormone associated with appetite and energy consuming regulation. It is currently believed that leptin functions not only on central nervous system, but also on the bone metabolism. It is getting clearer that there is a direct effect of leptin on osteoblast and bone formation. The deep studies of the mechanism of leptin will offer a new way for preventing and curing the bone metabolism diseases in human, such as osteoporosis. DATA SOURCES： Network search was done using Pubmed Database to find related articles in English from 1994, when leptin gene was discovered, and using Chinese Journal Full-text Database, Wanfang Database and Chinese Hospital Knowledge Database for selecting related articles in Chinese. The searching key words were ＂leptin, bone, bone formation, osteoblast＂. STUDY SELECTION： The materials were primarily scanned and the correlated articles were selected for full texts. The selection criteria：（1） studies related to leptin receptor and its expression on osteoblasts.（2）studies related to the effect of leptin on osteoblast proliferation and differentiation in vitro. （3）studies related to the effect of leptin on bone formation in vitro. The deletion criteria： repeated research. DATA EXTRACTION： Totally 447 papers related to leptin and bone were collected. Among them, 112 papers were referred to bone formation and 85 papers to osteoblast, respectively. Eighteen papers were studied in details after the elimination of duplicated studies. DATA SYNTHESIS： （1）The leptin receptor expresses on mice, rats and human osteoblasts, osteoblast cell line ROS17/2.8, and human osteoblast derived from bone marrow mesenchyrnal stem cells. （2）Leptin stimulates osteoblast proliferation and differentiation in vitro, with the mechanism differing from that of bone morphogenetic protein 2.（3）In vivo studies shows that there is a positive correlation between bone mineral density and circulating level of leptin; Leptin replacement therapy increases bone mass;Leptin may regulate bone formation through central nervous system, CONCLUSION： The osteoblast is the direct target of lcptin due to its expression of leptin receptor. Leptin affects osteoblast and bone formation ;by its peripheral and central pathways.