去甲斑蝥素对荷瘤裸鼠胆囊癌移植瘤的抗癌作用机制

目的 探讨去甲斑蝥素（NCTD）对荷瘤裸鼠胆囊癌移植瘤的抗癌作用机制。方法 在建立裸鼠胆囊癌移植瘤动物模型的基础上进行肿瘤增殖、侵袭、转移体内干预实验,实验分空白对照、氟尿嘧啶、NCTD、NCTD＋氟尿嘧啶4组。6周末应用链霉素亲和生物素复合物（SABC）法检测移植瘤增殖细胞核抗原（PCNA）、Ki-67、细胞周期素D1（cyclin D1）、p27、Bcl-2蛋白,逆转录PCR（RT-PCR）检测PCNA、cyclin D1、p27、Bcl-2、Bax、存活素（Survivin）基因mRNA。HE染色观察瘤周癌细胞浸润、侵袭,解剖显微镜下观察肺组织转移瘤结节,并采用SABC和RT-PCR检测nm23、金属蛋白酶2（MMP2）及其组织抑制剂（TIMP2）蛋白和mRNA。结果 NCTD组增殖相关PCNA、Ki-67、cyclin D1蛋白表达下降,p27蛋白表达上升;PCNA mRNA、cyclin D1 mRNA表达下降,p27 mRNA表达增高。NCTD组凋亡相关Bcl-2蛋白表达下降;Bcl-2 mRNA、Survivin mRNA表达下降,Bax mRNA表达增高。NCTD显著减少荷瘤鼠移植瘤的瘤周癌细胞浸润和肺转移结节（P〈0．01）;NCTD组转移相关MMP2蛋白表达下降,nm23、TIMP2蛋白表达上升;nm23-H,mRNA、TIMP2 mRNA表达增高。结论 NCTD抑制荷瘤裸鼠胆囊癌移植瘤增殖、侵袭和转移的机制可能与NCTD干扰胆囊癌移植瘤细胞周期,抑制细胞增殖,诱导细胞凋亡,阻止细胞迁移运动,以及影响细胞增殖、细胞周期调控、细胞凋亡、细胞基质溶解和转移相关基因蛋白表达有关。     

JAK/STAT通路在金属蛋白酶1组织抑制剂抑制肾小球系膜细胞凋亡中的作用

目的 探讨金属蛋白酶1组织抑制剂（TIMP-1）抑制大鼠肾小球系膜细胞（RMC）凋亡与Janus激酶/信号转导和转录激活子（JAK/STAT）通路的关系。 方法 用无血清培养基体外培养pcDNA3空载体、人正义、反义TIMP-1基因重组真核表达载体转染RMC。根据是否加JAK2特异性抑制剂AG490刺激24 h,将细胞分为未转染组、未转染＋AG490组、空载体组、空载体＋AG490组、正义组、正义＋AG490组、反义组和反义＋AG490组。另外设正常培养条件下的RMC作为正常对照组。应用流式细胞技术检测各组RMC的凋亡率。RT-PCR检测TIMP-1、bcl-xl、cyclin D1、p27kip1和JAK2 mRNA的表达。Western印迹检测胞质中JAK2、STAT3、STAT5及其相应磷酸化蛋白(p-JAK2、p-STAT3、p-STAT5)的表达。 结果 未转染组、正义组及反义组RMC凋亡率分别为（10.59±0.96）％、（7.08±0.43）％和（21.91±0.25）％，各组间差异有统计学意义(P < 0.05或P < 0.01)。在未加AG490的各组RMC中,bcl-xl和cyclin D1 mRNA在正义组中表达最高，反义组中最低，p27kip1 mRNA在反义组中表达最高。加入AG490后，各组细胞的凋亡率均显著增加（P < 0.01）；TIMP-1、bcl-xl和cyclin D1 mRNA表达均减少；p27kip1 mRNA表达均增加。在未加AG490的各组细胞中，p-JAK2、p-STAT3和p-STAT5在正义组中表达最高，反义组中最低。加入AG490后上述蛋白表达均减少，且正义＋AG490组最高，反义＋AG490组最低。 结论 TIMP-1表达受JAK/STAT信号通路调控，后者可通过上调前者的表达抑制RMC凋亡；TIMP-1通过JAK/STAT信号通路抑制RMC凋亡。 bcl-xl、cyclin D1和p27kip1参与了上述过程。     

EGCG对高糖环境下小鼠足细胞增殖和P21^Cip1、P27^Kip1表达的影响

目的：研究作为绿茶主要活性成分的EGCG对高糖环境下足细胞增殖和周期素激酶抑制剂P21^Cip1和P27^Kip1表达的影响,从而探讨其作用机制。方法：以高糖（25mmol/L）培养的小鼠足细胞为研究对象,维生素E为对照,以不同浓度EGCG（0.2,10,100μmol/L）培养24h、48h、72h,首先以相差显微镜观察足细胞形态改变;其次,以BrduELISA法检测细胞增殖;流式细胞仪分析足细胞G1/G0、S期、G2/M期百分比;RT-PCR检测细胞周期依赖型蛋白激酶抑制剂P21^Cip1mRNA和P27^Kip1mRNA表达。结果：（1）相差显微镜下观察,高糖刺激后24h,部分足细胞脱落,呈不规则形态。（2）BrduELISA法以正常糖为对照,高糖刺激24h后,足细胞增殖无统计学差异,48h和72h后足细胞增殖减少,有统计学差异（P〈0.05）;以高糖组为对照,高糖刺激24h,维生素E组和维生素E＋EGCG协同作用组促进足细胞增殖有统计学差异（P〈0.05）,EGCG（0.2,10,100μmol/L）作用组无统计学意义;48h实验结果和24h相同;72hEGCG（100μmol/L）维生素E组和维生素E＋EGCG协同作用组促进足细胞增殖作用有统计学差异（P〈0.01）。（3）不同浓度EGCG对高糖刺激后足细胞周期G1/G0期、S期、G2/M期百分比无统计学差异（P〉0.05）。（4）RT-PCR高糖刺激后24h,足细胞P21^Cip1mRNA表达有上升,但无统计学意义（P〉0.05）;随EGCG浓度增加,以维生素E为对照,P21^Cip1mRNA表达无统计学差异（P〉0.05）。正常糖组为对照,高糖刺激后24h足细胞P27^Kip1mRNA表达上调,有统计学差异（P〈0.01）,随EGCG浓度增加,P27^Kip1mRNA表达无统计学差异（P〉0.05）。结论：EGCG（100μmol/L）作用72h促进高糖环境下足细胞增殖,对细胞周期作用不明显,高糖刺激后24h足细胞P27^Kip1mRNA表达上调,EGCG对足细胞细胞周期依赖型蛋白激酶抑制P21^Cip1mRNA和P27^Kip1表达无明显影响,提示EGCG促高糖环境下足细胞增殖作用可能还存在其他机制。     

大鼠系膜细胞增殖时S期激酶相关蛋白2表达的变化及机制

目的：探讨系膜细胞增殖时细胞周期蛋白依赖性蛋白激酶抑制物p27^kip1的降解限速蛋白——S期激酶相关蛋白2（Skp2）表达的变化及其机制。方法：原代培养的大鼠系膜细胞同步后分为无血清组、20%胎牛血清（FCS）刺激组。MTT法检测细胞增殖;实时定量PCR和Western Blot检测p27^kip1和Skp2的mRNA、蛋白表达。结果：p27^kip1在静止期系膜细胞高丰度表达,20%FCS刺激诱导细胞增殖后p27^kip1蛋白表达显著下调;实时定量PCR研究结果显示p27^kip1的mRNA表达水平差异无统计学差异,p27^kip1蛋白和mRNA表达不一致。蛋白酶体抑制剂MG-132可显著改善系膜细胞增殖时p27^kip1蛋白水平的下降。Skp2表达在静止期系膜细胞几乎检测不出,20%FCS刺激诱导细胞增殖后Skp2表达量显著上调。结论：系膜细胞Skp2表达显著上调导致p27^kip1降解增加,可能是p27^kip1蛋白水平下降、系膜细胞增殖的重要原因,为进一步阐明疾病状态下系膜细胞增殖的机制提供了新的研究靶点。     

HBV-DNA阳性血清对系膜细胞增殖及其AT_1RmRNA和AT_2RmRNA表达的影响

目的：探讨携带HBV无肾损害者和乙型肝炎病毒相关性肾炎（HBV-GN）患者HBV-DNA阳性血清对体外培养系膜细胞增殖及AT1RmRNA、AT2RmRNA表达的影响,并初步探讨其临床意义。方法：以体外培养的人肾小球系膜细胞为对象,分别用健康人血清、携带HBV无肾损害者和HBV-GN患者HBV-DNA阳性血清刺激,采用噻唑蓝比色法（MTT）检测各组系膜细胞增殖水平,逆转录-多聚酶链反应（RT-PCR）法检测各组系膜细胞AT1RmRNA、AT2RmRNA的表达水平。结果：携带HBV无肾损害者和HBV-GN患者的两种HBV-DNA阳性血清可刺激系膜细胞增殖明显,其中48h高浓度组及72h中高浓度组与正常对照组比较差异有统计学意义。但携带HBV无肾损害者和HBV-GN患者的两种HBV-DNA阳性血清对系膜细胞增殖的影响差异无统计学意义。从单一指标来看,携带HBV无肾损害者和HBV-GN患者的两种HBV-DNA阳性血清对系膜细胞表达AT1RmRNA和AT2RmRNA的改变与正常对照组比较差异有统计学意义,但两组之间比较无明显差别。而从AT1RmRNA/AT2RmRNA比值来看,携带HBV无肾损害者和HBV-GN患者的两种HBV-DNA阳性血清同时使AT1RmRNA/AT2RmRNA比值上调,尤其在HBV-GN患者中48h中高浓度组和72h组AT1RmRNA/AT2RmRNA比值较携带HBV无肾损害者显著增加。结论：HBV-GN患者含高滴度HBV-DNA血清可导致系膜AT1RmRNA/AT2RmRNA表达失调,可能参与系膜细胞增殖,促进肾小球硬化、肾间质纤维化。     

乙型肝炎病毒X蛋白抑制足细胞增殖

目的 通过构建复制缺陷型腺病毒载体将乙型肝炎病毒（HBV）X基因（即HBx基因）导入足细胞株,探讨HBx蛋白对足细胞增殖的影响及其分子机制。 方法 采用pAdxsi系统构建携带HBx基因的复制缺陷型腺病毒载体。以瑞氏-吉姆萨染色观察细胞形态。以MTT检测和羧基荧光素二乙酸盐琥珀酰亚胺酯（CFDA-SE）荧光染料示踪细胞增殖的方法,对细胞增殖进行定量评估。采用流式细胞仪检测细胞周期分布。采用cyclin/DNA双参数流式细胞术和Western印迹检测细胞周期调控蛋白的表达。 结果 PCR和基因测序鉴定证实,Ad.HBx构建成功。Western印迹显示,足细胞感染Ad.HBx（感染复数MOI =100）后第3、5天均可表达相对分子质量为17 000的HBx蛋白,表明HBx可在足细胞株稳定表达。细胞形态学观察显示腺病毒感染后第5天Ad.HBx组细胞呈现明显的有丝分裂障碍特征,双核、多核和多形核细胞比例明显增加。MTT检测结果显示空白组和Ad组足细胞的生长曲线基本吻合,而Ad.HBx组细胞的生长曲线自第4天起较前两组偏低,至第5天时该差异具有统计学意义（P < 0.01）;同时,CFDA-SE细胞增殖示踪实验也证实,于腺病毒感染后第3天Ad.HBx组细胞的增殖速度已明显低于空白组和Ad组（增殖指数11.2比15.4、13.3）,且随时间推移进一步减慢（增殖指数32.5 比 61.6、54.0）,表明HBx可显著抑制足细胞增殖。细胞周期分析和细胞周期调控蛋白检测的结果显示,HBx可诱导足细胞周期G2/M阻滞,同时伴有cyclin B1、p21的表达上调及cyclin A的下调。 结论 乙肝病毒基因编码的HBx蛋白可使cyclin B1降解受阻,同时下调cyclin A和上调细胞周期负调蛋白p21的表达,导致细胞周期阻滞于G2/M期,从而抑制足细胞增殖。这可能是乙型肝炎病毒相关性肾炎患者肾小球足细胞缺失,肾脏病变慢性进展的重要机制之一。     

围手术期营养支持对结直肠癌患者细胞周期蛋白D1表达及复发转移的影响

目的 探讨围手术期营养支持对结直肠癌患者肿瘤细胞cyclin D1表达及复发转移的影响.方法 将120例结直肠癌患者按其是否行营养支持分为营养支持组（60例）和对照组（60例）.围手术期营养支持方案：葡萄糖、脂肪乳剂、氨基酸及微量元素等组成的营养液,行全胃肠外营养,术前7 d,术后3 d.采用原位杂交检测cyclin D1的表达;采用TUNEL法检测细胞凋亡;采用细胞核抗原免疫组织化学染色检测细胞增殖.结果营养支持治疗后,营养支持组和对照组患者肿瘤组织cyclin D1阳性表达率分别为（35.23±5.12）%和（37.53±5.31）%;增殖指数分别为（7.21±2.56）%和（8.75±3.84）%;凋亡指数分别为（53.45±7.74）%和（56.74±8.02）%;差异均无统计学意义（P＞0.05）.两组患者术后3年复发率分别为16.7%和15.0%,差异无统计学意义（P＞0.05）.结论 围手术期营养支持不会影响cyclin D1的表达,也不会促进肿瘤复发和转移.     

红花提取物对高糖处理的小鼠足细胞损伤的影响

目的:探讨红花提取物对高糖处理的小鼠足细胞增殖、凋亡和炎症因子分泌的影响及分子机制。方法:将小鼠足细胞MPC5分为对照(NC)组、高糖(HG)组、不同浓度红花提取物组、红花提取物+HG组、miR-NC+HG组、miR-516a-5p+HG组、anti-miR-NC+HG组、anti-miR-516a-5p+HG组、红花提取物+miR-NC+HG组、红花提取物+miR-516a-5p+HG组。MTT检测细胞活性;流式细胞术检测细胞凋亡;RT-qPCR检测miR-516a-5p表达水平;ELISA检测白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平。结果:红花提取物处理后,高糖处理的小鼠足细胞中细胞活性升高,细胞凋亡率降低,IL-1β、IL-6、TNF-α水平降低,miR-516a-5p表达水平降低(P0.05)。过表达miR-516a-5p促进高糖处理的小鼠足细胞炎症因子表达和细胞凋亡,抑制细胞增殖;抑制miR-516a-5p表达与其作用相反。miR-516a-5p过表达可以逆转红花提取物对高糖处理的MPC5细胞增殖、凋亡,炎症因子表达的影响。结论:红花提取物可能通过下调miR-516a-5p表达抑制高糖处理的小鼠足细胞炎症因子表达和细胞凋亡,促进细胞增殖。     

慢性肾衰竭兔血清对主动脉平滑肌细胞增殖及核因子κB活化的作用

目的 研究慢性肾衰竭兔血清对其主动脉平滑肌细胞增殖和核因子κB （NF-κB）活化的影响,并探讨其作用的可能机制。 方法 建立慢性肾衰竭兔模型,采集血清。采用原代培养的兔主动脉平滑肌细胞,用不同浓度的慢性肾衰竭兔血清刺激不同时间,四甲基偶氮噻唑盐（MTT）法检测细胞增殖;Hoechst33342染色观察细胞凋亡;Western印迹检测慢性肾衰竭血清对主动脉平滑肌细胞增殖细胞核抗原（PCNA）、NF-κB p65蛋白表达的影响;免疫荧光观察NF-κB p65核转位。 结果 （1）在较低浓度（≤10%）时,慢性肾衰竭兔血清对平滑肌细胞的增殖有明显的促进作用,且呈浓度、时间依赖性;但血清浓度继续增加后,对平滑肌细胞的促增殖作用却明显减弱,与正常血清组差异有统计学意义（P < 0.05）。（2）Hoechst33342染色表明,慢性肾衰竭血清在低浓度时（≤10%）细胞凋亡率和正常血清组差异无统计学意义（P > 0.05）,但高浓度（>10%）时,平滑肌细胞凋亡率增加,与正常血清组差异有统计学意义（P < 0.01）。（3）慢性肾衰竭血清刺激24 h后,低浓度促进PCNA、NF-κB p65蛋白表达,高浓度抑制PCNA、NF-κB p65表达,与正常血清组差异有统计学意义（P < 0.01）。（4）10%慢性肾衰竭血清与平滑肌细胞孵育24 h后免疫荧光显示,NF-κB p65发生了核转位。 结论 不同浓度的慢性肾衰竭兔血清可导致平滑肌细胞增殖或凋亡,其促增殖作用可能与其活化了NF-κB有关。本研究为防治慢性肾衰竭加速性动脉粥样硬化提供理论依据。     

细胞周期调控蛋白在人类肾小球肾炎中肾小管及间质细胞的表达及其意义

目的 观察人类肾小球肾炎时肾小管－间质细胞的细胞周期调控蛋白的表达情况。方法 采用免疫组织化学技术，检测19例肾小球肾炎患者肾穿刺标本中细胞周期正性调控蛋白周期素D1（cyclin D1)，周期素A（cyclin A0，细胞周期负性调控蛋白p21^CIP1（p21)和增殖细胞核抗原（PCNA）的表达。结果 在人类肾小球肾炎中肾小管上皮细胞及间质细胞均见cyclin D1,cyclin A及p21的表达，并与PCNA呈正相关。小管的阳性表达以间质病变I级和Ⅱ级组显著，间质阳性细胞数与小管间质病变程度及患者尿NAG活性呈显著正相关。结论 人类肾小球肾炎时，细胞周期调控蛋白参与肾小管上皮细胞及间质细胞的增殖，参与肾间质纤维化的发展。     

Podocyte expression of the CDK-inhibitor p57 during development and disease.

BACKGROUND: The mature podocyte is a terminally differentiated cell with a limited proliferative capacity. The precise cell cycle proteins necessary for establishing podocyte quiescence during development or permitting podocyte cell cycle re-entry in disease states have not been fully defined. Accordingly, we studied the role of the cyclin dependent kinase (CDK)-inhibitor p57Kip2 (p57) in modulating these processes. METHODS: The expression of p57 protein in relation to markers of DNA synthesis was examined in developing mouse kidneys, and in the passive Heymann nephritis (PHN) and anti-glomerular antibody models of glomerular disease by immunohistochemistry. The role of p57 in glomerulogenesis was explored by examining renal tissue from embryonic p57-/- mice, and the expression of p21, p27 and p57 protein and mRNA was examined in podocytes in vitro. RESULTS: The de novo expression of p57 during glomerulogenesis coincides with the cessation of podocyte proliferation, and the establishment of a mature phenotype, and p57 is expressed exclusively in podocytes in mature glomeruli. However, p57 knockout mice have normal glomerular podocyte development. In addition, mRNA but not protein levels of p57 increased upon differentiation of podocytes in vitro. There was a marked decrease in p57 expression in both animal models of podocyte injury. This was diffuse in PHN, whereas in the murine model, loss of expression of p57 occurred predominantly in proliferating podocytes, expressing proliferating cell nuclear antigen (PCNA). CONCLUSION: Despite the de novo expression of p57 protein coinciding with the cessation of primitive podocyte proliferation during glomerulogenesis, embryonic p57-/- mice glomeruli were histologically normal. Cultured podocytes did not require changes in p57 protein levels to undergo differentiation. These data suggest that p57 alone is not required for podocyte differentiation, and that other cell cycle regulators may play a role. Furthermore, although injury to mature podocytes in experimental glomerular disease is associated with a decrease in p57, the levels of all three members of the Cip/Kip family of CDK inhibitors appear to determine the capability of podocytes to proliferate.     

Podocyte cell cycle regulation and proliferation in collapsing glomerulopathies

BACKGROUND: Mature podocytes are growth-arrested because of the expression of cyclin-dependent kinase inhibitors. Under pathological conditions, podocytes may undergo mitosis, but not cell division. Exceptions to this rule are collapsing glomerulopathies (CGs), including HIV-associated nephropathy (HIVAN) and idiopathic CG, where podocytes undergo a dysregulation of their differentiated phenotype and proliferate. METHODS: To shed light on the mechanism underlying podocyte proliferation in CG, we analyzed the expression of the proliferation marker Ki-67, cyclins (A, D1), cyclin-dependent kinase inhibitors (p27, p57), and podocyte differentiation marker synaptopodin in eight cases of HIVAN and two cases of idiopathic CG. Normal fetal and adult kidneys served as controls. RESULTS: Both HIVAN and idiopathic CG showed a marked reduction in the expression of p27, p57, and cyclin D1 (absent in 69, 62, and 80% of all glomeruli, respectively). Cyclin A and Ki-67 were expressed in 11 and 29% of all glomeruli. Moreover, there was partial loss of synaptopodin and cyclin D1 expression in nonaffected glomeruli. CONCLUSIONS: The loss of p27 and p57 leading to expression of cyclin A may account for the activation of podocyte proliferation in CG. Furthermore, the loss of cyclin D1 from histologically normal glomeruli suggests a possible role of cyclin D1 in mediating the dysregulation of the podocyte cell cycle in CG. These novel findings offer insight into the molecular regulation of mature podocyte differentiation. Podocyte proliferation in CG provides evidence in support of a previously underestimated plasticity of mature podocytes.     

IgA肾病患者血清aIgA1对足细胞增殖及nephrin分子表达的影响

目的：观察IgA肾病（IgA nephropathy,IgAN）患者与正常人的血清热聚合IgA1（aggregated IgA1,aIgA1）对足细胞增殖及nephrin分子表达的影响。方法：利用亲和层析联合分子筛层析法分离获得原发性IgAN患者与健康人血清单体IgA1（monomeric IgA1,mIgA1）,将mIgA1热聚合为aIgA1,分别刺激小鼠MPC5足细胞株,利用MTT法检测aIgA1对足细胞增殖的影响,用RT-PCR法检测aIgA1干预后足细胞nephrin分子基因表达水平的改变。结果：不同浓度aIgA1刺激组间足细胞MTT吸光度的差异有统计学意义（P〈0.05）。RT-PCR实验发现正常人及患者的aIgA1刺激足细胞后,均可以时间依赖性及剂量依赖性的方式下调nephrin mRNA的表达,且患者的aIgA1下调nephrin表达的作用更明显（P〈0.01）。结论：IgAN患者与正常人的aIgA1均可以影响足细胞增殖,并下调足细胞nephrin mRNA的表达。患者aIgA1对足细胞nephrin mRNA表达的下调作用较正常人明显,在疾病过程中IgA1可能是加重足细胞损伤的原因之一。     

Cell-cycle regulatory proteins in podocyte cell in idiopathic nephrotic syndrome of childhood

BACKGROUND: The podocyte cell is believed to play an important role in idiopathic nephrotic syndrome (INS) of childhood. In adults with cellular and collapsing focal segmental glomerulosclerosis (FSGS), the expression of cell-cycle regulatory proteins such as p27, p57, and cyclin D is decreased and expression of cyclin A, Ki-67, and p21 is observed in podocyte cells suggestive of a dysregulated podocyte phenotype. We investigated for alterations in the expression of cyclin kinase inhibitors, p27, p57, p21, and cyclins D and A in the podocyte cell of children with INS. METHODS: Forty-two kidney biopsies were investigated; 14 with minimal-change disease (MCD), seven with diffuse mesangial hypercellularity (DMH), 12 with FSGS, four with Alport syndrome (AS), and five normal biopsies. The sections were examined by immunohistochemistry using dual staining method. Podocyte cells were first identified by Wilm's tumor-1 staining after which expressions of cell-cycle regulatory proteins were analyzed. A quantitative analysis was performed for the proportion of podocyte cells that expressed each cell cycle regulatory protein. RESULTS: On light microscopy, all podocyte cells expressed p27, while p57 and p21 expression was seen in a portion of podocyte cells in normal kidney biopsies. Cyclin D was expressed in a small percent of podocyte cells though the expression was more marked in mesangial and endothelial cells. Cyclin A expression was not seen in normal biopsies. The mean expression of p27 decreased significantly in order from normal (100%), MCD (45.9%), DMH (22.4%), and FSGS (16.7%), and the difference between MCD and FSGS was significant. p21 was significantly and equally reduced in MCD (2.3%), DMH (0%), and FSGS (0.7%) compared to normal (66.6%). There was no significant difference in expression of p57, cyclin D and cyclin A in the podocyte cells between normal and children with INS. Children with AS showed a significant decrease in p27 and p21 expression, while the expression of p57, cyclin D and cyclin A were unchanged from normal, thus demonstrating a pattern similar to INS. CONCLUSION: The podocyte cell in children with INS down-regulates expression of cyclin kinase inhibitors such as p21 and p27, but not p57, but does not up-regulate cyclin D and cyclin A that are needed to overcome the G1/S transition and move the cell forward in the cell cycle process. Thus, the podocyte cell remains trapped in the G1 arrest phase. In children with INS or AS, the dysregulated podocyte phenotype is different than the one described in adults with cellular or collapsing FSGS.     

LTAA方案治疗呈肾病综合征的儿童乙型肝炎病毒相关性肾炎

目的：探讨拉米夫定、雷公藤多苷、血管紧张素转换酶抑制剂及抗凝（LTAA方案）联合治疗儿童乙型肝炎病毒相关性肾炎（HBV—GN）的疗效。方法：以拉米夫定（100mg／d）、雷公藤多苷片（0．5mg·kg^-1·d^-1）、血管紧张素转换酶抑制剂（洛汀新5～10mg／d）及抗凝治疗7例呈肾病综合征或大量蛋白尿且血HBV—DNA≥1．0×100copy／ml的儿童HBV—GN，疗程12月。结果：6例为膜性肾病、1例膜增生性肾炎。6月时完全缓解（cR）者4例、部分缓解（PR）者3例，有效率57．14％，治疗12月时CR者6例、PR者1例，有效率100％。12月血清HBV—DNA均转阴。12月后停用拉米夫定和雷公藤多苷，继续服用其他药物，随访6～55个月[平均随访（24．1±15．4）个月]，血清HBV—DNA3例再次转阳，4例阴性，复发2例，CR者5例、PR者1例、无效（NR）者1例。其中2例出现轻度肝功能异常，保肝治疗后恢复正常。未出现乙型肝炎病毒变异株。结论：ITAA治疗方案是治疗儿童HBV—GN安全有效的方案。     

Mechanical stress reduces podocyte proliferation in vitro.

BACKGROUND: Mechanical stretch, a consequence of capillary glomerular hypertension, is thought to be the common final pathway for glomerulosclerosis in systemic hypertension, diabetes, reduced nephron number and focal segmental glomerulosclerosis. However, the effects of stretch on podocyte growth and the mechanisms that underlie this have not been elucidated. METHODS: Mouse podocyte growth (3H-thymidine, MTT-assay, FACS) was measured following the application of mechanical stretch created by vacuum. The expression of specific cell cycle regulatory proteins was examined by RNAse protection assay and Western blot analysis. Control cells were grown under similar conditions, but were not exposed to stretch. RESULTS: Mechanical stretch decreased DNA-synthesis (3H-thymidine incorporation) and cell number (MTT-assay) in podocytes at 24, 48 and 72 hours (P < 0.001 vs. control non-stretched cells), which was not due to apoptosis (Hoechst staining) nor cell detachment. Stretch decreased the mRNA and protein levels of cyclins D1, A and B1 within 24 hours. Stretching cells decreased the activity of Cdk2 (measured by histone H1 kinase assay) at 48 and 72 hours and Cdc2 at 72 hours. In contrast, stretch increased the protein levels of the cyclin dependent kinase inhibitors (CKI) p21Cip/Kip/Waf (p21) and p27Kip1 (p27) within the first 24 hours, and increased the mRNA levels of p57Kip2 (p57) at 72 hours. To examine the role of p21 in inhibiting proliferation induced by stretch, we studied p21-/- podocytes in culture. Stretch did not reduce proliferation in p21-/- podocytes (P> 0.05 vs. non-stretched podocytes; P < 0.001 vs. stretched p21+/+ podocytes). CONCLUSIONS: In contrast to mesangial cells, mechanical stretch decreases the growth of podocytes. This effect is mediated through the regulation of specific cell cycle regulatory proteins. These events may explain the apparent lack of podocyte proliferation in diseases correlated with capillary glomerular hypertension.     

Cyclin E-p27 opposition and regulation of the G1 phase of the cell cycle in the murine neocortical PVE: a quantitative analysis of mRNA in situ hybridization

We have analyzed the expression patterns of mRNAs of five cell cycle related proteins in the ventricular zone of the neocortical cerebral wall over the course of the neuronogenetic interval in the mouse. One set of mRNAs (cyclin E and p21) are initially expressed at high levels but expression then falls to a low asymptote. A second set (p27, cyclin B and cdk2) are initially expressed at low levels but ascend to peak levels only to decline again. These patterns divide the overall neuronogenetic interval into three phases. In phase 1 cyclin E and p21 levels of mRNA expression are high, while those of mRNAs of p27, cdk2 and cyclin B are low. In this phase the fraction of cells leaving the cycle after each mitosis, Q, is low and the duration of the G1 phase, TG1, is short. In phase 2 levels of expression of cyclin E and p21 fall to asymptote while levels of expression of mRNA of the other three proteins reach their peaks. Q increases to approach 0.5 and TG1 increases even more rapidly to approach its maximum length. In phase 3 levels of expression of cyclin E and p21 mRNAs remain low and those of the mRNAs of the other three proteins fall. TG1 becomes maximum and Q rapidly increases to 1.0. The character of these phases can be understood in part as consequences of the reciprocal regulatory influence of p27 and cyclin E and of the rate limiting functions of p27 at the restriction point and of cyclin E at the G1 to S transition.     

人卵巢黄素化颗粒细胞细胞周期蛋白D2的表达与卵巢功能及反应性的相关性研究

目的探讨人卵巢黄素化颗粒细胞细胞周期蛋白D2（cyclin D2）的表达与卵巢功能及超排卵过程中卵巢反应性的相关性。方法收集48例行体外受精-胚胎移植（IVF-ET）患者的卵巢黄素化颗粒细胞,根据取卵时卵泡发育数不同将卵巢反应性分为高反应组（12例）、中反应组（30例）及低反应组（6例）。采用免疫细胞化学方法检测颗粒细胞膜上eyclin D2及增殖细胞核抗原（PCNA）蛋白的表达;逆转录聚合酶链反应（RT-PCR）检测颗粒细胞cyclin D2 mRNA的表达水平;化学发光法测定基础血清卵泡刺激素（FSH）,人绒毛膜促性腺激素（hCG）日E2水平。分析颗粒细胞eyelin D2 mRNA及蛋白的表达与IVF临床各项参数、卵巢反应性的关系以及和颗粒细胞增殖活性PCNA标记指数（PCNA-LI）的相关性。结果（1）黄素化颗粒细胞cyclinD2蛋白表达与年龄、基础FSH水平及促性腺激素（Gn）支数呈负相关（r=-0．547,P〈0．01;r=-0．456,P〈0．05;r=-0．451,P〈0．05）;cyclinD2蛋白表达与获卵数和hCG日E2水平呈正相关（r=0．592,P〈0．01;r=0．626,P〈0．01）;高、中和低反应三组cyclinD2蛋白表达有显著统计学差异（F=4．995,P〈0．05）。（2）黄素化颗粒细胞cyclin D2 mRNA表达与年龄、基础FSH水平呈负相关（r=-0．510,P〈0．05;r=-0．891,P〈O．01）;与获卵数和hCG日E2水平呈正相关（r=0．629,P〈0．01;r=0．524,P〈0．05）;高、中和低反应三组cyclin D2 mRNA的表达有显著统计学差异CF=8．843,P〈0．01）。（3）黄素化颗粒细胞cyclin D2蛋白及mRNA表达与PCNA-LI均呈显著正相关（r=0．696,P〈0．01;r=0．498,P〈0．0S）。结论黄素化颗粒细胞cyclin D2 mRNA及蛋白的表达可反映卵巢储备功能并与卵巢反应性正相关。cyclin D2可能通过调节颗粒细胞的增殖分化参与卵泡的发育。     

来氟米特对糖尿病大鼠葡萄糖转运蛋白-1 mRNA表达及细胞外基质的影响

目的：探讨来氟米特对链脲佐菌素（STZ）诱导的糖尿病大鼠肾脏葡萄糖转运蛋白-1（GLUT）mRNA表达及细胞外基质的影响及其意义。方法：采用STZ腹腔注射法建立糖尿病动物模型。将大鼠随机分为正常对照组（A组）,糖尿病组（B组）,来氟米特干预组（C组）。第4、8、12周末各组随机选取4只大鼠处死并收集标本,记录体重、右肾重、检测血糖、血肌酐、血尿素氮、血胆固醇、血三酰甘油、24h尿蛋白排泄量。用RT-PCR方法检测肾皮质GLUT-1 mRNA表达水平。肾组织行HE、PAS染色,并用免疫组化法检测肾组织层黏连蛋白及Ⅳ型胶原蛋白的表达情况。结果：（1）与A组相比,B组大鼠造模成功后0周,血糖明显增高（P〈0.01）,但24h尿蛋白排泄量无明显增高（P〉0.05）;4周时体重明显降低（P〈0.01）,肾重指数、尿素氮、肌酐、胆固醇、三酰甘油、24h尿蛋白排泄量、肾皮质GLUT-1 mRNA表达明显增加（P均〈0.01）;C组12周时肾皮质GLUT-1 mRNA表达量,肾重指数、肌酐已无明显增加（P〉0.05）。（2）与B组相比,C组8周时尿素氮、肌酐降低（P均〈0.05）,胆固醇、24h尿蛋白排泄量和肾皮质GLUT-1 mRNA表达量均明显下降（P均〈0.01）;12周时体重增加（P〈0.05）,肾重指数、三酰甘油明显下降（P〈0.01）。肾组织HE、PAS染色病理学观察：B组光镜下肾小球肥大,系膜细胞增生,系膜基质弥漫性的或结节性的增多,肾小球、肾小管基底膜增厚,而C组这些病理改变明显减轻。免疫组织化学染色：B组可见系膜区Ⅳ型胶原蛋白和层黏连蛋白的大量沉积,C组也可见Ⅳ型胶原蛋白和层黏连蛋白的沉积,但较B组明显减轻。结论：来氟米特能减少糖尿病大鼠尿蛋白排泄量,纠正糖尿病大鼠的脂代谢紊乱,抑制肾脏肥大、减轻肾脏的纤维化硬化程度。其机制可能与下调系膜细胞上GLUT-1 mRNA的表达量及功能活性有关,最终延?