固醇调节元件结合蛋白2在软骨细胞退变过程中的表达

背景：近期研究证实了固醇调节元件结合蛋白2基因在骨关节炎发生过程中起重要作用,但其具体发病机制尚未完全清楚。 目的：通过白细胞介素1β体外诱导关节软骨细胞退变,观察固醇调节元件结合蛋白2在软骨细胞退变过程中的表达变化。 方法：体外分离培养C57BL/6J小鼠关节软骨细胞,将第2代软骨细胞随机分为4组：对照组、白细胞介素1β 24,48,     72 h组。后3组细胞分别以10 μg/L白细胞介素1β干预细胞。 结果与结论：软骨细胞经白细胞介素1β刺激后呈肥大化表现,软骨细胞活性随白细胞介素1β刺激时间的延长而逐渐降低。与对照组相比,白细胞介素1β 24,48,72 h组软骨细胞中固醇调节元件结合蛋白2与固醇调节元件结合蛋白裂解激活蛋白 mRNA表达水平增加,而蛋白聚糖和Ⅱ型胶原mRNA表达水平降低。提示白细胞介素1β能抑制软骨细胞增殖和细胞重要基质成分表达,诱导其出现肥大化退行性改变,且在退变的过程中,固醇调节元件结合蛋白2表达逐渐上调,与软骨关键基因的表达呈负向变化关系。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

固醇调节元件结合蛋白-1基因多态性与冠心病的关系

目的:探讨固醇调节元件结合蛋白-1(SREBP-1)基因多态性与冠心病(CHD)之间的关系。方法:应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)和基因测序技术对湖北汉族101例CHD患者(CHD组)和122例健康人(对照组)SREBP-1基因18号外显子54G/C(简称18c)、SREBP-1a基因18号内含子20C/G(简称18a)基因多态性进行检测分析,同时结合糖代谢水平、血脂水平来探讨二者之间的关系。结果:18c基因多态性在对照组与CHD组中的基因型频率和等位基因分布差异均有统计学意义(P<0.05);剔除CHD组中的2型糖尿病(T2DM)病例后,对照组与CHD组中的基因型频率分布差异无统计学意义(P>0.05);湖北汉族人群中不存在18a基因多态性。结论:18c基因多态性与湖北汉族人群冠脉病变的发生有关;C等位基因可能通过影响糖代谢水平而与CHD的发生间接相关。     

激活的固醇调节元件结合蛋白在内皮细胞移行中的作用

目的 探讨固醇调节元件结合蛋白(SREBP)在内皮细胞移行中的激活及其作用.方法 培养牛主动脉内皮细胞,应用Western blot分析、即时定量PCR、细胞移行测定、Cdc42活性测定等方法 ,研究了SREBP的激活在内皮细胞移行中的作用,以及这个过程中涉及SREBP的潜在的信号转达.结果 (1)内皮细胞移行组与非移行组相比,SREBP被显著激活(P<0.05);(2)内皮细胞移行组与非移行组相比,SREBP下游基因,低密度脂蛋白受体、羟甲基戊二酰辅酶A还原酶及脂肪酸合成酶的mRNA的表达显著增加(P<0.05);(3)SREBP裂解激活蛋白RNAi和SREBP抑制剂(25-羟化胆固醇)能够明显抑制内皮细胞的移行;(4)在各种模型中SREBP的抑制导致内皮细胞移行的减少;(5)SREBP裂解激活蛋白缺陷型、S2P缺陷型及S1P缺陷型细胞株,表现为内皮细胞移行损伤;(6)抑制内皮细胞SREBP活性后,Rho、Cdc42活性也被抑制.结论 SREBP是内皮细胞移行中的关键调控分子,靶向干预SREBP将可能成为治疗异常内皮细胞移行相关疾病的一条新途径.     

T0901317对apoE基因敲除小鼠肝脂质蓄积及肝固醇调节元件结合蛋白-1c表达的影响

目的本文研究肝X受体(LXR)激动剂T0901317对apoE基因敲除小鼠肝脏脂质蓄积及肝脏固醇调节元件结合蛋白1-c(SREBP-1c)表达的影响。方法52只雄性apoE基因敲除小鼠被随机分成4组:基础组(n=10)对照组(n=14)、LXR激动剂治疗组(n=14)、d.LXR激动剂预防组(n=14)。各组小鼠均被给予高脂/高胆固醇饲料喂养;基础组小鼠被赋形剂灌胃处理8周;对照组小鼠被赋形剂灌胃处理14周;LXR激动剂治疗组小鼠在前8周被赋形剂灌胃处理,后6周被T0901317灌胃处理;LXR激动剂预防组小鼠被T0901317灌胃处理14周。使用HE和油红O染色方法观察小鼠肝脏脂质蓄积情况;采用实时定量PCR和蛋白质印迹方法分别检测肝脏SREBP-1cmRNA和蛋白质的表达。结果实验结果显示LXR激动剂治疗组和预防组小鼠肝脏脂质滴较对照组明显增多,组织结构排列逐渐紊乱(P<0.05);LXR激动剂治疗组和预防组小鼠肝脏SREBP-1cmRNA和蛋白质表达上调(P<0.05)。结论LXR激动剂T0901317能增加高脂高胆固醇饲料喂养的apoE基因敲除小鼠肝脏脂质蓄积并上调SREBP-1c表达。     

固醇调节元件结合蛋白1c基因多态性rs2297508、rs11868035与甘肃汉族、东乡族人群2型糖尿病的相关性

目的 探讨固醇调节元件结合蛋白1c(sterol regulatory element binding protein-lc,SREBP-lc)基因多态性rs2297508、rs11868035在甘肃汉族、东乡族人群中的分布及其与2型糖尿病(type 2diabetes mellitus,T2DM)的相关性.方法 选择汉族2型糖尿病患者342例以及正常对照343人,东乡族2型糖尿病患者218例以及正常对照238人,采用聚合酶链反应-变性高效液相色谱法检测SREBP-1c基因型,采用氧化酶法或放免法测定血糖、胰岛素及血脂水平.采用卡方检验进行统计学分析.结果 SREBP-lc基因多态位点rs2297508、rs11868035在汉族和东乡族正常对照者中的基因型和等位基因频率分布差异无统计学意义(P＞0.05).上述位点在汉族、东乡族人群2型糖尿病患者C等位基因和CC基因型频率均明显高于对照组,差异均有统计学意义(P＜0.01).在汉族对照组中,rs2297508的C等位基因携带者的低密度脂蛋白胆固醇水平明显高于GG者,其差异有统计学意义(P＜o.05).在东乡族对照组中,CC基因型的低密度脂蛋白胆固醇水平明显高于GG者,其差异有统计学意义(P＜0.05).结论 SREBP-lc基因多态性rs2297508、rs11868035在甘肃汉族和东乡族人群中均与2型糖尿病发病存在关联.C等位基因可能是罹患2型糖尿病的危险因素之一.上述多态性在汉族和东乡族人群中的分布并无差异.SREBP-le基因多态性rs2297508可能与低密度脂蛋白胆固醇升高有关.     

固醇调节元件结合蛋白2在软骨细胞退变过程中的表达（英文）

背景:近期研究证实了固醇调节元件结合蛋白2基因在骨关节炎发生过程中起重要作用,但其具体发病机制尚未完全清楚。目的:通过白细胞介素1β体外诱导关节软骨细胞退变,观察固醇调节元件结合蛋白2在软骨细胞退变过程中的表达变化。方法:体外分离培养C57BL/6J小鼠关节软骨细胞,将第2代软骨细胞随机分为4组:对照组、白细胞介素1β24,48,72 h组。后3组细胞分别以10μg/L白细胞介素1β干预细胞。结果与结论:软骨细胞经白细胞介素1β刺激后呈肥大化表现,软骨细胞活性随白细胞介素1β刺激时间的延长而逐渐降低。与对照组相比,白细胞介素1β24,48,72 h组软骨细胞中固醇调节元件结合蛋白2与固醇调节元件结合蛋白裂解激活蛋白mR NA表达水平增加,而蛋白聚糖和Ⅱ型胶原mR NA表达水平降低。提示白细胞介素1β能抑制软骨细胞增殖和细胞重要基质成分表达,诱导其出现肥大化退行性改变,且在退变的过程中,固醇调节元件结合蛋白2表达逐渐上调,与软骨关键基因的表达呈负向变化关系。     

固醇调节元件结合蛋白-1c基因54G/C多态性对高糖低脂膳食诱导的健康青年人血脂比值的影响

目的 探讨固醇调节元件结合蛋白-1c(sterol regulatory element-binding protein-1c,SREBP-1c)基因54G/C多态性对健康青年血脂比值的影响及在高糖低脂(high-carbohydrate/low-fat,HC/LF)膳食诱导的变化中的作用.方法 对56名健康志愿者,给予7 d平衡膳食和6 d HC/LF膳食,平衡膳食蛋白、脂肪、碳水化合物含量分别为15%,31%,54%,HC/LF膳食分别为15%,15%,70%.于第1 d,第8 d及第14 d抽取空腹12 h静脉血,测定血脂及血糖水平,计算血脂比值.分离血基因组DNA,聚合酶链反应-限制性酶切法分析SREBP-1c基因54G/C多态性.分析不同基因型间血脂比值及血糖的差异.结果 不同基因型受试者血脂比值及血糖基础值差异无统计学意义.平衡膳食后,无论是在受试人群整体还是将男女分组分析,不同基因型之间血脂比值及血糖均无统计学意义.HC/LF膳食后,女性C等位基因携带者低密度脂蛋白胆固醇/高密度脂蛋白胆固醇比值(loW density lipoprotein cholesterol/high density lipoprotein cholesterol,LDL-C/HDL-C)较GG纯合子显著升高(P＜0.05).与HC/LF膳食前相比,在受试人群整体,总胆固醇(total cholesterol,TC)/HDL-C比值和LDL-C/HDL-C在各基因型中均显著降低(P＜0.05).男女分组分析发现,HC/LF膳食后甘油三酯triglyceride(TG)/HDL-C比值和血浆致动脉硬化指数log(TG/HDL-C)在女性GG基因型受试者较膳食前显著升高(P＜0.05);而TC/HDL-C、LDL-C/HDL-C在HC/LF膳食后显著下降(P＜0.05),且不受性别和SREBP-1c基因54G/C位点多态性影响.结论 SREBP-1c基因54G/C多态性影响HC/LF膳食诱导的健康青年女性TG/HDL-C、log(TG/HDL-C)改变.C等位基因可能是一个对防止女性HC/LF膳食诱导的甘油三酯升高的保护性因素.     

固醇调节元件结合蛋白-1c基因54G/C多态性对高糖低脂膳食诱导的健康青年人血脂比值的影响

Objective To investigate the effects of 54G/C polymorphism of sterol regulatory elementbinding protein-1c gene (SREBP-1c)on serum lipid ratios and their response to high-carbohydrate/low-fat(HC/LF) diet in healthy youth. Methods After a regular diet for 7 days of wash-out, 56 healthy youth (22.89±1.80 yrs) were given HC/LF diet for 6 days. The regular diet contained 54% carbohydrate, 15%protein, and 31% fat of the total energy. The HC/LF diet contained 70% carbohydrate, 15% protein, and 15% fat of the total energy. The serum lipids and glucose were measured on the 1st, 8th and 14th days.The ratios of TG/HDL-C, log (TG/HDL-C), TC/HDL-C, and LDL-C/HDL-C were calculated. The 54G/C polymorphism of SREBP-1c gene was analyzed by PCR-RFLP method. Results No significant difference was found in lipid ratios and glucose at baseline and after regular diet in subjects with different genotypes in either the whole studied population or in males or females only. However, after HC/LF diet, LDL-C/HDL-C was significantly lower in females carrying the C allele than those of GG homozygotes (P＜ 0.05).Compared with those before HC/LF diet, TC/HDL-C and LDL-C/HDL-C were significantly decreased in all the subjects (P＜0.05). When gender was taken into account, significant increase of TG/HDL-C and log(TG/HDL-C) was found only in females with GG genotype (P＜0.05). All the subjects experienced significant decrease of TC/HDL-C and LDL-C/HDL-C regardless of their genders and genotypes (P＜0.05). Conclusion The 54G/C polymorphism of SREBP-1c gene can influence the response of TG/HDL-C and log(TG/HDL-C) to HC/LF diet in females. The C allele may be a protective factor to prevent the increase of TG induced by HC/LF diet in females.     

固醇调节元件结合蛋白-1c基因54G/C多态性对高糖低脂膳食诱导的健康青年人血脂比值的影响

Objective To investigate the effects of 54G/C polymorphism of sterol regulatory elementbinding protein-1c gene (SREBP-1c)on serum lipid ratios and their response to high-carbohydrate/low-fat(HC/LF) diet in healthy youth. Methods After a regular diet for 7 days of wash-out, 56 healthy youth (22.89±1.80 yrs) were given HC/LF diet for 6 days. The regular diet contained 54% carbohydrate, 15%protein, and 31% fat of the total energy. The HC/LF diet contained 70% carbohydrate, 15% protein, and 15% fat of the total energy. The serum lipids and glucose were measured on the 1st, 8th and 14th days.The ratios of TG/HDL-C, log (TG/HDL-C), TC/HDL-C, and LDL-C/HDL-C were calculated. The 54G/C polymorphism of SREBP-1c gene was analyzed by PCR-RFLP method. Results No significant difference was found in lipid ratios and glucose at baseline and after regular diet in subjects with different genotypes in either the whole studied population or in males or females only. However, after HC/LF diet, LDL-C/HDL-C was significantly lower in females carrying the C allele than those of GG homozygotes (P＜ 0.05).Compared with those before HC/LF diet, TC/HDL-C and LDL-C/HDL-C were significantly decreased in all the subjects (P＜0.05). When gender was taken into account, significant increase of TG/HDL-C and log(TG/HDL-C) was found only in females with GG genotype (P＜0.05). All the subjects experienced significant decrease of TC/HDL-C and LDL-C/HDL-C regardless of their genders and genotypes (P＜0.05). Conclusion The 54G/C polymorphism of SREBP-1c gene can influence the response of TG/HDL-C and log(TG/HDL-C) to HC/LF diet in females. The C allele may be a protective factor to prevent the increase of TG induced by HC/LF diet in females.     

PDZ结构域蛋白1缺失促进骨关节炎软骨细胞衰老

背景:骨关节炎以关节软骨的退变为主要病理特征,作为软骨中唯一的细胞,软骨细胞的衰老是骨关节炎发病的重要机制之一。但是骨关节炎的具体发病机制目前仍未清楚,因此探索疾病过程中的分子机制和信号通路变化,希望为骨关节炎的诊断与治疗提供新的生物靶点和研究方向。目的:探讨在骨关节炎进程中软骨PDZ结构域蛋白1(PDZ Domain Containing 1,PDZK1)对软骨细胞衰老的影响。方法:(1)8周龄C57/BL6小鼠随机分为实验组和假手术组,实验组又随机分为4,8周2个亚组。实验组小鼠行右侧膝关节内侧半月板胫骨韧带切除,游离内侧半月板,诱导骨关节炎;假手术组小鼠则仅切开关节囊而不行内侧韧带切除和半月板游离,检测PDZK1表达量。(2)用Ⅱ型胶原酶消化法分离新生C57/BL6乳鼠软骨细胞并培养,用10μg/L白细胞介素1β构建骨关节炎体外细胞模型,并利用siRNA-PDZK1敲低PDZK1,共分为未处理组、白细胞介素1β处理组(白细胞介素1β组)、siRNA-PDZK1组(si-PD组)、白细胞介素1β与siRNA-PDZK1共同刺激组(si-PD+白细胞介素1β组)。检测软骨细胞PDZK...     

SREBP-2沉默抑制衣霉素诱导的软骨细胞内质网应激

目的:探究固醇调节元件结合蛋白2(SREBP-2)对衣霉素诱导的软骨细胞内质网应激(ERS)的影响。方法:分离人正常软骨细胞和骨关节炎(OA)软骨细胞培养,衣霉素和SREBP-2 siRNA分别处理正常软骨细胞。24 h后,实时荧光定量PCR检测对微小RNA-185(miR-185)表达的影响,流式细胞术检测对细胞凋亡的影响,Western blot法检测对SREBP-2、CHOP、p-e IF2α和ATF4等ERS相关蛋白,Bcl-2、Bax和caspase-3等凋亡相关蛋白水平的影响;caspase-3活性试剂盒检测对细胞caspase-3活性的影响。结果:与对照组相比,OA组和衣霉素组SREBP-2表达增加,miR-185表达降低(P0.05)。SREBP-2 siRNA转染可明显阻断衣霉素引起的miR-185降低(P0.05)。miR-185过表达能够下调SREBP-2蛋白水平(P0.05)。与对照组相比,OA组和衣霉素组CHOP、pe IF2α和ATF4的蛋白水平明显上调,Bcl-2表达下调,Bax和caspase-3表达增加(P0.05);SREBP-2沉默处理则显著逆转上述蛋白表达(P0.05)。细胞凋亡率与上述细胞凋亡相关蛋白的变化趋势一致(P0.05)。与衣霉素组相比,SREBP-2 siRNA转染明显下调caspase-3活性,miR-185抑制则明显逆转上述作用(P0.05)。结论:SREBP-2沉默可通过上调miR-185抑制衣霉素诱导的软骨细胞ERS和细胞凋亡。     

The role of macrophages in the disappearance of Meckel’s cartilage during mandibular development in mice

Meckel’s cartilage is a supporting tissue in the embryonic mandible that disappears during development; however, the precise mechanisms of this disappearance process are still undetermined. In this study, we observed morphological changes of Meckel’s cartilage with development and analyzed the factors which might be related to this process. Meckel's cartilage of ICR strain mice from 14 to 19 days gestation (E14-19) were used in this study. Histological and immunohistochemical studies indicated the decrease in the amount of sulfated glycoconjugates and the localization of type I collagen in the Meckel's cartilage matrix during development. Chondrocytes also expressed high acid phosphatase activities at these stages. An organ culture study indicated that Meckel's cartilage at E17 disappeared during the cultivation period, while the cartilage at E14 did not disappear. Massive penetration of macrophages into the perichondrium was detected at E16. RT-PCR analysis of Meckel's cartilage indicated the expression of interleukin-1β, type I collagen, MMP-9 at E17, but not at E14. MIP-1α, the candidate molecule for macrophage chemoattractant factor, was expressed at E14. These results indicated the dynamic matrix changes of Meckel's cartilage during development and suggested that the functional changes of chondrocytes in synthesis of type I collagen might be induced by interleukin-1β secreted by the penetrating macrophages.