高脂饮食诱导肥胖小鼠模型中氧化应激、炎症递质对骨代谢的影响及其可能机制

摘要
图/表
参考文献
相关文章 (0)

全文: PDF (0 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS)

摘要目的：探讨高脂饮食诱导肥胖小鼠模型中氧化应激和炎症递质对骨代谢的影响及其可能机制。方法：选用5周龄C57BL/6雄性小鼠16只，随机平均分为正常饮食组、高脂饮食组，分别用正常饮食和高脂饮食喂养。于实验16周末，测各组动物体质量，处死后取内脏脂肪并测量内脏脂肪/体质量比值；用ELISA法测量血清抗酒石酸酸性磷酸酶5b（TRACP-5b）、血清骨钙素（OC）、白介素-6（IL-6）和肿瘤坏死因子-α（TNF-α）；分别用硫代巴比妥酸（TBA）法和羟胺法检测胫骨骨组织丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性；用骨密度仪检测右侧股骨骨密度（BMD）；分别用免疫组织化学技术和实时荧光定量PCR（RT-qPCR）技术检测骨组织骨保护素（OPG）和核因子-κB受体活化因子配体（RANKL）蛋白及mRNA的表达；HE染色光镜观察左侧股骨组织形态学改变。结果：与正常饮食组相比，高脂饮食组体质量、内脏脂肪/体质量比值、骨组织RANKL mRNA/OPG mRNA比值、血清TRACP-5b、IL-6和TNF-α水平、骨组织RANKL表达及骨组织MDA均明显升高，差异均具统计学意义（P＜0.05）；而血清OC水平、骨组织OPG表达、骨组织SOD及BMD均明显下降，差异均具统计学意义（P＜0.05）。在组织形态学上，发现高脂饮食组股骨干骺端骨小梁分布稀疏，骨小梁变细及断裂，伴骨髓腔中有大量脂肪浸润。各指标的相关分析结果显示：BMD与骨组织SOD呈正相关（r=0.627，P＜0.01），与内脏脂肪/体质量比值（r=-0.858，P＜0.01）、骨组织MDA均呈负相关（r=-0.538，P＜0.01）；SOD与OPG mRNA呈显著正相关（r=0.637，P＜0.01），与TNF-α（r=-0.673，P＜0.01）、IL-6（r=-0.874，P＜0.01）、RANKL mRNA（r=-0.760，P＜0.01）及RANKL/OPG比值（r=-0.768，P＜0.01）呈显著负相关；而MDA与TNF-α、IL-6、OPG mRNA、RANKL mRNA以及RANKL/OPG无显著相关性（P＞0.05）。结论：高脂饮食诱导肥胖能导致骨质疏松病理组织学改变，其机制可能与其上调炎症递质表达和氧化应激增加有关。

	服务
	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	朱再胜1
	戴爽2
	吴玲2
	郑靖宇2
	黄卡特2
	李剑敏2

关键词 ：肥胖；骨质疏松；高脂饮食；骨保护素；核因子-&kappa, B受体活化因子配体；氧化应激；小鼠

Abstract：Objective: To investigate the effects of inflammatory mediator and oxidative stress on bone metabolism in high fat diet-induced obesity mice and the underlying mechanism. Methods: Sixteen C57BL/6 mice aged 5 weeks were randomly divided into two groups. High fat diet group (HFD) was fed with high fat diet while normal fat diet group (NFD) was fed with normal fat diet. At the end of 16 weeks, the visceral fat was weighed and the visceral fat/body mass ratio was assessed. The levels of TRACP-5b, OC, IL-6 and TNF-α in serum were measured by ELISA. The content of malondiadehyde (MDA) and the activity of superoxide dismutase (SOD) in shin-bone were analyzed by using hydroxylamine assay and TBA colorimetry. The bone mineral density (BMD) of right femurs were detected by Hologic QDR-4500 Bone Densitometer. The expressions of OPG and RANKL in bone tissue were detected by immunohistochemical technique and RT-qPCR respectively. Histological changes in the left femurs were studied with HE stained under light microscopy. Results: Compared to the NFD group mice, the body weight,the ratio of visceral fat/body mass and the RANKL/OPG in bone, the serum levels of TRACP5b, IL-6, TNF-α, the expressions of RANKL and the content of MDA in bone were increased in HFD group mice significantly (P<0.05). But the serum level of OC, the expressions of OPG, the activity of SOD in bone and the BMD were decreased in HFD group mice significantly (P<0.05). Histologically, the volume of bones trabecular were decreased and the bones trabecular distribution were sparse, thinner and fracture and more adipocytes infiltrated in bone marrow in HFD group. The results of correlation analysis shows that BMD was positively correlated with SOD of bone (r=0.627, P<0.01) and negatively correlated with the ratio of visceral fat/body mass (r=-0.858, P<0.01), MDA level of bone (r=-0.538, P<0.01); SOD was positively correlated with OPG mRNA (r=0.637, P<0.01) and negatively correlated with TNF-α (r=-0.673, P<0.01), IL-6 (r=-0.874, P<0.01), RANKL mRNA (r=-0.760, P<0.01) and the ratio of the RANKL/OPG in bone(r=-0.768, P<0.01), but MDA shows no correlation with TNF-α, IL-6, OPG mRNA, RANKL mRNA and the ratio of the RANKL/OPG in bone (P>0.05). Conclusion: High fat diet induced obesity can lead to the increase of bone resorption and the pathological histology changes of osteoporosis and the BMD decline. The underlying mechanism may be associated with its upreguating of inflammatory mediator and enhancing oxidative stress in bone.

Key words： obesity osteoporosis high fat diet osteoprotegerin receptor activator for nuclear factor-κB ligand oxidative stress mice

收稿日期: 2014-04-09

基金资助:国家自然科学基金资助项目（81170204）；温州市科技局科研基金资助项目（Y20120038）

通讯作者: 李剑敏，教授，Email：wzyxyljmin@163.com

作者简介: 朱再胜（1979-），男，浙江乐清人，主治医师，医学硕士

链接本文:

https://xb.wmu.edu.cn/CN/ 或 https://xb.wmu.edu.cn/CN/Y2014/V44/I9/631

[1]Bonewald LF, Johnson ML. Osteocytes, mechanosensing and Wnt signaling[J]. Bone, 2008, 42(4): 606-615.
[2]Sawakami K, Robling AG, Ai M, et al. The Wnt co-receptor LRP5 is essential for skeletal mechanotransduction but not for the anabolic bone response to parathyroid hormone treatment[J]. J Biol Chem, 2006, 281(33): 23698-23711.
[3]Zhao LJ, Liu YJ, Liu PY, et al. Relationship of obesity with osteoporosis[J]. J Clin Endocrinol Metab, 2007, 92(5): 1640-1646.
[4]Cao JJ, Gregoire BR, Gao H. High-fat diet decreases cancel-lous bone mass but has no effect on cortical bone mass in the tibia in mice[J]. Bone, 2009, 44(6): 1097-1104.
[5]Halade GV, El Jamali A, Williams PJ, et al. Obesity-mediat-ed inflammatory microenvironment stimulates osteoclasto-genesis and bone loss in mice[J]. Exp Gerontol, 2011, 46(1): 43-52.
[6]顾芹, 陈芳, 叶红英, 等. 不同干预治疗对C57BL/6J雄性肥胖小鼠肿瘤坏死因子-α的影响[J]. 上海医学, 2010, 33(1): 81-84.
[7]Halloran BP, Ferguson VL, Simske SJ, et al. Changes in bone structure and mass with advancing age in the male 57BL/6J mouse[J]. J Bone Miner Res, 2002, 17(6): 1044-1050.
[8]Surwit RS, Kuhn CM, Cochrane C, et al. Diet-induced type II diabetes in C57BL/6J mice[J]. Diabetes, 1988, 37(9):1163-1167.
[9]Collins S, Martin TL, Surwit RS, et al. Genetic vulnerability to diet-induced obesity in the C57BL/6J mouse: phys-iological and molecular characteristics[J]. Physiol Behav,2004, 81(2): 243-248.
[10]Ikeda K, Tsukui T, Tanaka D, et a1. Conditional expression of human bone Gla protein in osteoblasts causes skeletal abnormality in mice[J]. Biochem Biophys Res Commun, 2012, 424(1): 164-169.
[11]Hannon RA, Clowes JA, Eagleton AC, et a1. Clinical per-formance of immunoreactive tartrate-resistant acid phos-phatase isoform 5b as a marker of bone resorption[J]. Bone, 2004, 34(1): 187-194.
[12]向青, 苏楠, 刘忠厚, 等. 第二代骨吸收生化标志物—血清抗酒石酸酸性磷酸酶5b的临床研究[J]. 中国骨质疏松杂志, 2002, 8(4): 331-332.
[13]Xiao Y, Cui J, Li YX, et al. Dyslipidemic high-fat diet af-fects adversely bone metabolism in mice associated with im-paired antioxidant capacity[J]. Nutrition, 2011, 27(2): 214-220.
[14]王娈, 阎胜利, 王芳, 等. 幼鼠骨骼发育中高脂饮食的影响[J]. 中国组织工程研究与临床康复, 2011, 15(7): 1321-1326.
[15]Keaney JF Jr, Larson MG, Vasan RS, et al. Obesity and sys-temic oxidative stress: clinical correlates of oxidative stress in the Framingham study[J]. Arterioscler Thromb Vasc Biol,2003, 23(3): 434-439.
[16]Ott M, Gogvadze V, Orrenius S, et al. Mitochondria, oxida-tive stress and cell death[J]. Apoptosis, 2007, 12(5): 913-922.
[17]黄海涛, 金昱. 氧化应激在骨质疏松发生中的作用研究进展[J]. 延边大学医学学报, 2012, 35(3): 68-70.
[18]吴骞, 陈建庭. 氧化应激在骨质疏松中的作用[J]. 中国骨质疏松杂志, 2010. 16(3): 222-224.
[19]Bai XC, Lu D, Liu AL, et al. Reactive oxygen species stimulates receptor activator of NF-kappaB ligand expres-sion in osteoblast[J]. J Biol Chem, 2005, 280(17): 1749717506.
[20]Khoala S. Minireview: the OPG/RANKL/RANK system[J].Endocrinology, 2001, 142(12): 5050-5055.
[21]Tanaka S, Nakamura K, Takahasi N, et al. Role of RANKL in physiological and pathological bone resorption and ther-apeutics targeting the RANKL-RANK signaling system[J].Immunol Rev, 2005, 208: 30-49.
[22]Gravallese EM, Manning C, Tsay A, et al. Synovial tis-sue in rheumatoid arthritis is a source of osteoclast diferen-tiation factor[J]. Arthritis Rheum, 2000, 43(2): 250-258.
[23]Feng X. Regulatory roles and molecular signaling of TNF family members in osteoclasts[J]. Gene, 2005, 350(1): 1-13.
[24]Liu XH, Kirschenbaum A, Yao S, et al. Interactive effect of interleukin-6 and prostaglandin E2 on osteoclastogenesis via the OPG/RANKL/RANK system[J]. Ann NY Acad Sci, 2006, 1068: 225-233.
[25]Liang JH, Li YN, Qi JS, et al. Peroxynitrite-induced protein nitration is responsible for renal mitochondrial damage in diabetic rat[J]. J Endocrinol Invest, 2010, 33(3): 140-146.