重组骨形态发生蛋白-7在肾纤维化治疗中的研究进展

骨形态发生蛋白-7是一种多功能细胞因子,与相应受体结合后经信号转导发挥作用,受多种拮抗剂和激动剂的调控.肾问质纤维化是多种肾脏疾病进展到终末期肾衰竭的共同途径和主要病理基础.在多项慢性肾脏疾病动物模型的研究中,发现给予重组骨形态发生蛋白-7能够抑制或逆转肾小管间质纤维化,改善肾功能.骨形态发生蛋白-7可能通过维持肾小管细胞表型、逆转上皮-间质细胞转变、减少细胞外基质、抑制炎症等环节发挥抗纤维化作用.文中就重组骨形态发生蛋白-7在肾纤维化治疗中的研究进展进行综述.     

肺成纤维细胞在肺纤维化进程中的作用

肺纤维化(pulmonary fibrosis,PF)是一种严重的肺间质疾病,主要病理特点是早期的弥漫性肺泡炎,后期大量成纤维细胞病理性增殖转型及细胞外基质(extracellular matrix,ECM)进行性异常积聚并取代正常的肺组织结构。其发病原因很多,如病原微生物、粉尘、药物、化学制剂等多种因素均可诱导产生肺纤维化,但发病机制尚不清楚。在其发生过程中,肺成纤维细胞(fibroblast,FB)起着重要的促进作用,主要通过自身的异常增殖与转型,大量分泌细胞外基质直接触发PF和作用于上皮细胞及一些炎症细胞间接参与PF进程。该文通过整理成纤维细胞在PF中的作用,进一步了解肺纤维化的发病机制。     

Mesenchymal stem cells in fibrotic diseases—the two sides of the same coin

Fibrosis is caused by extensive deposition of extracellular matrix (ECM) components, which play a crucial role in injury repair. Fibrosis attributes to ~45% of all deaths worldwide. The molecular pathology of different fibrotic diseases varies, and a number of bioactive factors are involved in the pathogenic process. Mesenchymal stem cells (MSCs) are a type of multipotent stem cells that have promising therapeutic effects in the treatment of different diseases. Current updates of fibrotic pathogenesis reveal that residential MSCs may differentiate into myofibroblasts which lead to the fibrosis development. However, preclinical and clinical trials with autologous or allogeneic MSCs infusion demonstrate that MSCs can relieve the fibrotic diseases by modulating inflammation, regenerating damaged tissues, remodeling the ECMs, and modulating the death of stressed cells after implantation. A variety of animal models were developed to study the mechanisms behind different fibrotic tissues and test the preclinical efficacy of MSC therapy in these diseases. Furthermore, MSCs have been used for treating liver cirrhosis and pulmonary fibrosis patients in several clinical trials, leading to satisfactory clinical efficacy without severe adverse events. This review discusses the two opposite roles of residential MSCs and external MSCs in fibrotic diseases, and summarizes the current perspective of therapeutic mechanism of MSCs in fibrosis, through both laboratory study and clinical trials.     

肾小管上皮细胞线粒体氧化损伤在肾间质纤维化中的病理学机制研究

目的：研究肾小管上皮细胞线粒体氧化损伤在肾间质纤维化中的病理学机制。方法：80只雄性大鼠随机平分为假手术组和UUO模型组,每组40只,行大鼠左侧输尿管结扎术,假手术组游离左侧输尿管但不予结扎,其余手术与UUO模型组相同。分别于术后d3、d7、d10、d14、d21每组处死8只,取大鼠左侧肾脏。①检测并比较假手术组和UUO模型组大鼠线粒体相关基因的表达水平;②检测两组大鼠肾脏组织COX和SOD含量变化;③检测两组大鼠肾脏组织RIF指数变化;④检测并比较肾体比、肾功能和肾组织Hyp含量动态变化。结果：与假手术组大鼠相比,①UUO模型组大鼠的线粒体相关基因的表达水平显著升高（P＜0.05）,包括线粒体mtDNA、再生基因（PGC1a、NRF1和Tfam）、断裂基因（Mfn1、Mfn2和Opa1）和融合基因（Drp1和Fis1）;②UUO模型组大鼠在造模后10d、14d和21d,肾脏组织中的COX水平显著升高（P＜0.05）,SOD水平显著降低（P＜0.05）,造模时间越长,UUO模型组大鼠COX水平越高（P＜0.05）,SOD水平越低;③UUO模型组大鼠造模后10d、14d和21d,肾脏组织RIF指数均显著升高（P＜0.05）;④UUO模型组大鼠肾体比明显升高且一直维持在较高水平（P＜0.05）,造模时间越长,模型大鼠血清Scr和BUN水平及肾组织Hyp含量水平逐渐升高,与假手术组相比均具有显著差异（P＜0.05）。结论：与假手术组大鼠相比,UUO模型组大鼠肾组织中的线粒体更活跃,线粒体基因、再生基因、断裂基因和融合基因含量升高,COX含量升高,SOD含量降低,RIF指数升高,肾体比、血清Scr和BUN和肾组织Hyp水平显著升高。     

整合素在肿瘤转移中的作用机制研究进展

机体重要的黏附分子整合素(Integrins)在细胞与细胞外基质间及细胞与细胞间的黏附作用已为人共知。以往的研究证实整合素与肿瘤转移有着密切关系,文献分析表明,这一研究领域一直是肿瘤转移方面的研究热点,该文着重概述近5年国际上关于整合素在肿瘤转移的作用机制方面的研究进展,表明整合素介导了大量的非配体依赖的信号转导通路促进了肿瘤转移。这使得整合素在肿瘤转移中的作用机制更加明确和深入,也为整合素抑制剂的开发带来了光明的前景。     

橙皮苷对TGF-β1诱导的A549非小细胞肺癌细胞上皮间质转化的影响

目的：探讨橙皮苷对转化生长因子-β1（transforming growth factor-β1,TGF-β1）诱导的人非小细胞肺癌细胞上皮-间质转化的影响。方法：以A549人非小细胞肺癌细胞系作为研究对象。用MTT法,分别检测橙皮苷对正常培养条件或TGF-β1刺激下细胞增殖的影响。应用2种方法评估橙皮苷对TGF-β1刺激条件下A549细胞的上皮间质转化：圆形度值定量评估细胞的形态变化;双抗体夹心酶联免疫吸附法（enzyme linked-immuno-sorbent assay,ELISA）检测上皮细胞钙黏蛋白（E-cadherin,E-cad）、ɑ-平滑肌肌动蛋白（ɑ-smooth muscle actin,ɑ-SMA）、基质金属蛋白酶抑制因子-1（tissue inhibitors of metalloproteinases-1,TIMP-1）和基质金属蛋白酶-9（metallopreoteinases-9,MMP-9）水平。结果：0~40 μmol·L^-1的橙皮苷对正常培养条件或TGF-β1刺激后A549细胞的增殖没有显著影响。5 ng·mL^-1 TGF-β1能够诱导A549细胞的上皮间质转化：由上皮特征的铺路石状的细胞形态转化为梭形形态,圆形度值减少;E-cad分泌量减少和ɑ-SMA合成量增加。另外,MMP-9分泌量增加,MMP-9/TIMP-1比值增加。在细胞出现形态改变后,应用橙皮苷（20 μmol·L^-1或40 μmol·L^-1）能够降低ɑ-SMA、MMP-9水平和MMP-9/TIMP-1比值,增加E-cad水平,对细胞的圆形度值没有影响。结论：橙皮苷减轻TGF-β1诱导的非小细胞肺癌细胞的上皮间质转化程度,对非小细胞肺癌的转移和扩散有一定的抑制作用。     

The interplay between ASMase signaling pathway and NLRP3 in the epithelial to mesenchymal transition of HBE cells induced by silica

Epithelial–mesenchymal transition (EMT) is an important part of pulmonary fibrosis. Our earlier study illustrated that the acid sphingomyelinase (ASMase) pathway plays significant role in silica (SiO₂)-induced transformation of lung fibroblasts into myofibroblasts. The metabolite of ASMase, ceramide (Cer), activates the inflammatory response by activating Nod-like receptor protein 3 (NLRP3) in macrophages, and NLRP3 is also involved in the EMT process. However, whether ASMase and NLRP3 are involved in regulating SiO₂-induced EMT has not been confirmed. In this study, an in vitro model of EMT in human bronchial epithelial (HBE) cells was established by SiO₂ dust staining to investigate the role of ASMase and NLRP3 in EMT and to provide new clues for the molecular mechanism of silicosis. HBE cells were stained with 100 μg/ml SiO₂ dust for 72 h to establish the EMT model. The ASMase inhibitor desipramine decreased the level of S1P and the expression of α-smooth muscle actin (α-SMA) and NLRP3 in SiO₂ dust-stained HBE cells, whereas the expression of E-cadherin (E-cad) increased. The NLRP3 inhibitor MCC950 inhibited the secretion of interleukin-1β (IL-1β) and decreased the expression of NLRP3, Caspase-1, and α-SMA in SiO₂ dust-stained HBE cells, whereas E-cad expression increased and ASMase activity and S1P levels decreased. It was concluded that SiO₂ dust increases the release of the inflammatory factor and induces EMT in HBE cells. Inhibition of ASMase activity or NLRP3 expression reduced the SiO₂ dust-induced cell inflammatory response and slowed the occurrence of EMT in HBE cells. Therefore, NLRP3 and ASMase may interact in SiO₂ dust-induced EMT in HBE cells.     

Midkine in nephrogenesis,hypertension and kidney diseases

Midkine (MK; K; gene abbreviation, Mdk: mus musculus, MDK: homo sapiens) is a multifunctional heparin-binding growth factor that regulates cell growth, survival and migration as well as anti-apoptotic activity in nephrogenesis and development. Proximal tubular epithelial cells are the main sites of MK expression in the kidneys. The pathophysiological roles of MK are diverse, ranging from the development of acute kidney injury (AKI) to the progression of chronic kidney disease, often accompanied by hypertension, renal ischaemia and diabetic nephropathy. The obvious hypertension that develops in Mdk^+/+ mouse models of renal ablation compared with Mdk^−/− mice eventually leads to progressive renal failure, such as glomerular sclerosis and tubulointerstitial damage associated with elevated plasma angiotensin (Ang) II levels. MK is also induced in the lung endothelium by oxidative stress and subsequently up-regulated by ACE, which hydrolyzes Ang II to induce further oxidative stress, thus accelerating MK generation; this leads to a vicious cycle of positive feedback in the MK-Ang II pathway. Kidney–lung interactions involving positive feedback between the renin-angiotensin system and MK might partly account for the pathogenesis of hypertension and kidney damage. MK is also involved in the pathogenesis of AKI and diabetic nephropathy through the recruitment of inflammatory cells. In contrast, MK plays a protective role against crescentic glomerulonephritis, by down-regulating plasminogen activator inhibitor-1. These diverse actions of MK might open up new avenues for targeted approaches to treating hypertension and various renal diseases.

Linked Articles

This article is part of a themed section on Midkine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-4     

Cyclophilin D promotes tubular cell damage and the development of interstitial fibrosis in the obstructed kidney

Cyclophilin D (CypD) is an important component in mitochondrial‐dependent tubular cell death in acute kidney injury. However, it is not known whether CypD contributes to tubular cell damage in chronic interstitial fibrosis. We investigated this question in the unilateral ureter obstruction (UUO) model of renal interstitial fibrosis. Groups of CypD^?/? and wild type (WT) mice were killed 7 or 12 days after UUO surgery. The significant tubular cell apoptosis seen in WT UUO was significantly reduced in CypD^?/? UUO based on TUNEL and cleaved caspase 3 staining. Other markers of tubular cell damage; loss of E‐cadherin and AQP1 expression, were also reduced in the CypD^?/? UUO kidney. This reduced tubular damage was associated with less inflammation and a partial protection against loss of peritubular capillaries. The prominent accumulation of α‐SMA+ myofibroblasts and interstitial collagen deposition seen in WT UUO was significantly reduced in CypD^?/? UUO on day 12, but not day 7. Activation of several pro‐fibrotic signalling pathways (p38 MAPK, JNK and Smad3) was unaltered in CypD^?/? UUO, arguing that CypD acts independently to promote renal fibrosis. CypD deletion in cultured tubular cells attenuated oxidative stress‐induced pro‐inflammatory, pro‐fibrotic and apoptotic responses; however, responses to angiotensin II and LPS were unaffected. In contrast, CypD deletion in cultured renal fibroblasts did not affect PDGF‐induced proliferation or TGF‐β1‐induced collagen I expression, suggesting no direct role of CypD in the fibroblast response. In conclusion, we have identified a role for CypD in chronic tubular cell damage and in the development of renal interstitial fibrosis.     

肾损伤分子1对顺铂诱导的大鼠急性肾损伤的预测研究

目的 对肾损伤分子1 (KIM-1)预测顺铂诱导的大鼠急性肾损伤进行研究.方法 以顺铂为工具药,诱导大鼠急性肾损伤模型.采集尿样、肾组织样本,对肾组织样本进行病理切片检查,以确定造模是否成功.用ELISA法测定尿样中KIM-1蛋白含量;RT-PCR法检测大鼠肾脏KIM-1基因表达水平;Western blotting法检测大鼠肾组织中KIM-1的蛋白含量,并通过免疫组化法定性定位分析大鼠肾组织中KIM-1蛋白表达情况,以确定急性肾损伤发生时KIM-1是否可以作为敏感的检测指标.结果 当模型组大鼠肾脏皮髓交界处出现程度不等的肾小管扩张,肾小管上皮细胞变性、坏死脱落,基底膜裸露等病理改变时,ELISA法检测尿KIM-1,RT-PCR法和Western blotting法检测肾组织中的KIM-1表达水平均明显升高,免疫组化显示模型组所有大鼠在肾皮髓交界部位可见大量的染色阳性的肾小管,该染色阳性区域与组织病理学检查中的异常肾小管分布区域基本一致.结论 KIM-1可作为一种敏感的生物标志物对顺铂诱导的大鼠急性肾损伤进行预测.     

间充质干细胞治疗特发性肺纤维化药理机制研究进展

间充质干细胞（MSCs）具有多种分化能力,可以直接迁移到损伤组织中并分化为肺泡上皮细胞,还可以分泌并释放多种细胞因子和外泌体,调节炎症和免疫反应。特发性肺纤维化（IPF）是与年龄相关、发病机制尚不明确的慢性进行性肺部疾病,临床上使用的吡非尼酮和尼达尼布仅能缓解症状。MSCs在治疗IPF方面具有广阔的应用前景,就目前关于MSCs治疗特发性肺纤维化的药理机制以及该疗法所存在的局限性进行综述和探讨。     

青藤碱通过调控PI3K/AKT通路介导的上皮间质转化抑制胰腺癌AsPC-1细胞侵袭和转移

目的 探讨青藤碱对胰腺癌AsPC-1细胞上皮间质转化（epithelial mesenchymal transition,EMT）、侵袭和转移的影响及机制。方法 采用不同浓度青藤碱作用胰腺癌AsPC-1细胞后,划痕愈合试验检测细胞愈合能力,Transwell试验检测迁移细胞数和侵袭细胞数,Western blotting检测E-cadherin、N-cadherin、Vimentin、PI3K、p-PI3K、AKT、p-AKT蛋白表达。结果 青藤碱降低AsPC-1细胞相对迁移率、迁移细胞数、侵袭细胞数。青藤碱上调E-cadherin蛋白表达、下调N-cadherin、Vimentin蛋白表达。青藤碱降低p-PI3K/PI3K、p-AKT/AKT比值。胰岛素生长因子-1逆转青藤碱对E-cadherin蛋白表达的上调和对N-cadherin、Vimentin蛋白表达的下调作用。TGF-β逆转青藤碱对AsPC-1细胞相对迁移率、迁移细胞数、侵袭细胞数的降低作用。结论 青藤碱通过调控PI3K/AKT通路介导的EMT,抑制AsPC-1细胞侵袭和转移。     

Novel action of the chalcone isoliquiritigenin as a cystic fibrosis transmembrane conductance regulator (CFTR) inhibitor: potential therapy for cholera and polycystic kidney disease

Overstimulation of cAMP-activated Cl(-) secretion can cause secretory diarrhea. Isoliquiritigenin (ISLQ) is a plant-derived chalcone that has a wide range of biological activities. The present study thus aimed to investigate the effect of ISLQ on cAMP-activated Cl(-) secretion in human intestinal epithelium, especially the underlying mechanism and therapeutic application. Short-circuit current analysis of human intestinal epithelial (T84) cell monolayers revealed that ISLQ dose-dependently inhibited cAMP-activated Cl(-) secretion with an IC(50) of approximately 20 μM. ISLQ had no effect on either basal short-circuit current or Ca(2+)-activated Cl(-) secretion. Apical Cl(-) current analysis of T84 cell monolayers indicated that ISLQ blocked mainly the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channels, but not other unidentified cAMP-dependent Cl(-) channels. ISLQ did not affect intracellular cAMP levels or cell viability. ISLQ completely abolished the cholera toxin-induced transepithelial Cl(-) secretion in T84 cells and reduced the cholera toxin-induced intestinal fluid secretion in mouse closed loop models by 90%. Similarly, ISLQ completely inhibited the cAMP-activated apical Cl(-) current across monolayers of Madin-Darby Canine Kidney (MDCK) cells and retarded cyst growth in MDCK cyst models by 90%. This study reveals a novel action of ISLQ as a potent CFTR inhibitor with therapeutic potential for treatment of cholera and polycystic kidney disease.     

The role of gadolinium chelates in the mechanism of nephrogenic systemic fibrosis: A critical update

Nephrogenic systemic fibrosis (NSF) is an iatrogenic scleroderma-like fibrosing systemic disorder occurring in patients with severe or end-stage renal disease. It was established as a new clinical entity in the year 2000. A causal role for gadolinium chelates (GC), widely used as contrast agents for magnetic resonance imaging, was suggested six years later. It rapidly appeared that the occurrence of NSF was associated with prior administration of GCs with lower thermodynamic stability, leading to warnings being published by health authorities and learned societies worldwide. Although a role for the chelated form of the less stable GCs has been proposed, the most commonly accepted hypothesis involves the gradual release of dissociated gadolinium in the body, leading to systemic fibrosis. However, the entire chain of events is still not fully understood in a causal way and many uncertainties remain.     

不同途径移植骨髓间充质干细胞对慢性肾病大鼠肾脏纤维化的影响

目的观察不同途径移植骨髓间充质干细胞(BMSCs)对慢性肾病(CKD)大鼠的治疗效果及寡聚化结构域样受体蛋白(NLRP)3炎症小体对肾间质纤维化的影响。方法雄性SD大鼠50只,其中2只用于体外分离培养BMSCs;36只大鼠CKD造模(左肾切除+多次尾静脉注射阿霉素)成功后随机分为模型(CKD)组、肾动脉移植BMSCs(A-M)组、尾静脉移植BMSCs(V-M)组;另设假手术(SHAM)组,每组12只,尾静脉输注等量生理盐水。移植BMSCs后第7、14天检测血肌酐、尿素氮、24 h尿蛋白水平;HE染色、Masson三色染色观察肾脏病理结构改变及纤维化情况,免疫组化染色观察核苷酸结合NLRP3、凋亡相关微粒蛋白(ASC)、半胱氨酸天冬氨酸蛋白酶(Caspase)-1表达情况。结果与SHAM组相比,CKD组、A-M组、V-M组7 d、14 d血肌酐、尿素氮、24 h尿蛋白均显著升高(P<0.05)。BMSCs移植7 d、14 d后,A-M组、V-M组与CKD组比较血肌酐、尿素氮、24 h尿蛋白降低,且A-M组低于V-M组(P<0.05)。HE染色、Masson染色结果示,A-M组...