miR-34a mediates oxaliplatin resistance of colorectal cancer cells by inhibiting macroautophagy via transforming growth factor-β/Smad4 pathway

To investigate whether microRNA (miR)-34a mediates oxaliplatin (OXA) resistance of colorectal cancer (CRC) cells by inhibiting macroautophagy via the transforming growth factor (TGF)-β/Smad4 pathway.METHODSmiR-34a expression levels were detected in CRC tissues and CRC cell lines by quantitative real-time polymerase chain reaction. Computational search, functional luciferase assay and western blotting were used to demonstrate the downstream target of miR-34a in CRC cells. Cell viability was measured with Cell Counting Kit-8. Apoptosis and macroautophagy of CRC cells were analyzed by flow cytometry and transmission electron microscopy, and expression of beclin I and LC3-II was detected by western blotting.RESULTSExpression of miR-34a was significantly reduced while expression of TGF-β and Smad4 was increased in CRC patients treated with OXA-based chemotherapy. OXA treatment also resulted in decreased miR-34a levels and increased TGF-β and Smad4 levels in both parental cells and the OXA-resistant CRC cells. Activation of macroautophagy contributed to OXA resistance in CRC cells. Expression levels of Smad4 and miR-34a in CRC patients had a significant inverse correlation and overexpressing miR-34a inhibited macroautophagy activation by directly targeting Smad4 through the TGF-β/Smad4 pathway. OXA-induced downregulation of miR-34a and increased drug resistance by activating macroautophagy in CRC cells.CONCLUSIONmiR-34a mediates OXA resistance of CRC by inhibiting macroautophagy via the TGF-β/Smad4 pathway.

Spatial signalling mediated by the transforming growth factor-β signalling pathway during tooth formation

Tooth development relies on sequential and reciprocal interactions between the epithelial and mesenchymal tissues, and it is continuously regulated by a variety of conserved and specific temporal-spatial signalling pathways. It is well known that suspensions of tooth germ cells can form tooth-like structures after losing the positional information provided by the epithelial and mesenchymal tissues. However, the particular stage in which the tooth germ cells start to form tooth-like structures after losing their positional information remains unclear. In this study, we investigated the reassociation of tooth germ cells suspension from different morphological stages during tooth development and the phosphorylation of Smad2/3 in this process. Four tooth morphological stages were designed in this study. The results showed that tooth germ cells formed odontogenic tissue at embryonic day （E） 14.5, which is referred to as the cap stage, and they formed tooth-like structures at E16.5, which is referred to as the early bell stage, and E18.5, which is referred to as the late bell stage. Moreover, the transforming growth factor-β signalling pathway might play a role in this process.

Tetrandrine inhibits activation of rat hepatic stellate cells in vitro via transforming growth factor-β signaling

AIM: To investigate the effect of various concentrations of tetrandrine on activation of quiescent rat hepatic stellate cells (HSCs) and transforming growth factor-β (TGF-β) signaling in vitro.METHODS: HSCs were isolated from rats by in situperfusion of liver and 18% Nycodenz gradient centrifugation, and primarily cultured on uncoated plastic plates for 24 hwith DMEM containing 20% fetal bovine serum (FBS/DMEM) before the culture medium was substituted with 2% FBS/DMEM for another 24 h. Then, the HSCs were cultured in 2% FBS/DMEM with tetrandrine (0.25, 0.5, 1,2 mg/L, respectively). Cell morphological features were observed under an inverted microscope, smooth muscleα-actin (α-SMA) was detected by immunocytochemistry and image analysis system, laminin (LN) and type Ⅲprocollagen (PCⅢ) in supernatants were determined byradioimmunoassay. TGF-β1 mRNA, Smad 7 mRNA and Smad 7 protein were analyzed with RT-PCR and Western blotting, respectively.RESULTS: Tetrandrine at the concentrations of 0.25-2 mg/L prevented morphological transformation of HSC from the quiescent state to the activated one, while α-SMA, LN and PCⅢ expressions were inhibited. As estimated by gray values, the expression of α-SMA in tetrandrine groups (0.25, 0.5, 1, 2 mg/L) was reduced from 21.3% to 42.2%(control: 0.67, tetrandrine groups: 0.82, 0.85, 0.96, or 0.96, respectively, which were statistically different from the control, P＜0.01), and the difference was more significant in tetrandrine at 1 and 2 mg/L. The content of LN in supernatants was significantly decreased in tetrandrine groups to 58.5%, 69.1%, 65.8% or 60.0% that of the control respectively, and that of PCⅢ to 84.6%, 81.5%,75.7% or 80.7% respectively (P＜0.05 vs control), with no significant difference among tetrandrine groups. RTPCR showed that TGF-β1 mRNA expression was reduced by tetrandrine treatments from 56.56% to 87.90% in comparison with the control, while Smad 7 mRNA was increased 1.4-4.8 times. The TGF-β1 mRNA and Smad 7 mRNA expression was in a significant negative correlation (r= -0.755, P＜0.01), and both were significantly correlated with α-SMA protein expression (r = -0.938, P＜0.01;r = 0.938, P＜0.01, respectively). The up-regulation of Smad 7 protein by tetrandrine (1 mg/L)was confirmed by Western blotting as well.CONCLUSION: Tetrandrine has a direct inhibiting effect on the activation of rat HSCs in culture. It up-regulates the expression of Smad 7 which in turn blocks TGF-β1 expression and signaling.

Total flavone of Abelmoschus manihot suppresses epithelial-mesenchymal transition via interfering transforming growth factor-β1 signaling in Crohn's disease intestinal fibrosis

AIM To explore the role and mechanism of total flavone of Abelmoschus manihot(TFA) on epithelial-mesenchymal transition(EMT) progress of Crohn's disease(CD) intestinal fibrosis.METHODS First,CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial(IEC-6) cells and select the optimal concentrations of TFA for our further studies.Then cell morphology,wound healing and transwell assays were performed to examine the effect of TFA on morphology,migration and invasion of IEC-6 cells treated with TGF-β1.In addition,immunofluorescence,real-time PCR analysis(q RT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress.Moreover,western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways.Further,the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by q RTPCR,western blotting,morphology,wound healing andtranswell assays.RESULTS In this study,TFA promoted transforming growth factor-β1(TGF-β1)-induced(IEC-6) morphological change,migration and invasion,and increased the expression of epithelial markers and reduced the levels of mesenchymal markers,along with the inactivation of Smad and MAPK signaling pathways.Moreover,we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-β1-induced EMT in IEC-6 cells.Importantly,co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-β1-induced EMT in IEC-6 cells than either one of them.CONCLUSION These findings could provide new insight into the molecular mechanisms of TFA on TGF-β1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.

TGF-β1/SMAD SIGNALING PATHWAY MEDIATES p53-DEPENDENT APOPTOSIS IN HEPATOMA CELL LINES

Objective To determine whether transforming growth factor betal (TGF-β1)/Smad signaling pathway mediates p53-dependent apoptosis in hepatoma cell lines.Methods Three human hepatic carcinoma cell lines, HepG2, Huh-7, and Hep3B, were used in this study.TGF-β1-induced apoptosis in hepatic carcinoma cell lines was analyzed using TUNEL assay.For identifying the mechanism of apoptosis induced by TGF-β1, cell lines were transfected with a TGF-β1-inducible luciferase reportor plasmid containing Smad4 binding elements.After transfection, cells were treated with TGF-β1, then assayed for luciferase activity.Results The apoptosis rate of HepG2 cell lines (48.51%± 8.21%) was significantly higher than control ( 12.72%±2.18%, P<0.05).But TGF-β1 was not able to induce apoptosis of Huh-7 and Hep3B cell lines.The relative luciferase activity of TGF-β1-treated HepG2 cell lines (4.38) was significantly higher than control (1.00, P< 0.05).But the relative luciferase activity of TGF-β1-treated Huh-7 and Hep3B cell lines less increased compared with control.Conclusions HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh-7 cell lines.Smad4 is a central mediator of TGF-β1 signaling transdution pathway.TGF-β1/Smad signaling pathway might mediate p53-dependent apoptosis in hepatoma cell lines.

转化生长因子β胞内信号转导与Smads蛋白

Transforming growth factor-β (TGF-β) is a multifunctional peptide growth factor with a wide range of effects. TGF-β signals are conveyed through cell-surface serine/threonine kinase receptors to the downstream cytoplasmic mediators, known as Smads proteins. Receptor-regulated Smads become phosphorylated by activated type Ⅰ receptors and form heteromeric complexes with a common Smad-Smad4, which translocates into the nucleus to regulate gene transcription. Inhibitory Smads inhibit the activation of receptor-regulated Smads. There are positive, negative and feedback regulations in the Smads mediated TGF-β signaling pathway.

TGF-β_1/smads信号转导通路在IPF病程中的作用初探

特发性肺间质纤维化为一种严重的呼吸系统疾病,其特点主要为慢性、弥漫性、进行性以及限制性通气功能障碍,该病病因复杂且预后较差,目前尚缺乏安全有效的治疗方案。近年来,细胞因子网络在IPF发生、进展过程中的作用越发受到重视,其中TGF-β1为目前研究最多、公认的重要因素。该文简单叙述IPF的分子机制、TGF-β1/smads信号转导通路的作用途径,并对其致IPF的病理作用给出较为详尽的解答。

卡维地洛对异丙肾上腺素诱导的大鼠心肌重构中TGF-β/Smads信号传导通路的作用

目的研究TGF-β/Smads信号传导通路在异丙基肾上腺素诱导的心肌重构中的作用及卡维地洛的治疗机制。方法 30只SD大鼠,随机分为3组:20只SD大鼠背部皮下注射异丙基肾上腺素5 mg/(kg·d)10d,建立心肌重构模型。随机分为2组,模型组和卡维地洛组。予卡维地洛组连续灌胃卡维地洛10 mg/(kg·d)4周。4周后测心重指数(CWI);HE、Masson染色观察心肌组织病理变化;半定量RT-PCR法及免疫组化染色检测心肌组织中TGF-β1、Smad3、Smad7 mRNA及蛋白表达情况。结果模型组可见心肌细胞肥大、伸长,肌质变性,核大、深染,Masson染色可见心肌胶原纤维明显增多,治疗组大鼠心肌细胞病理改变较模型组明显减轻;CWI:模型组较对照组CWI升高(P<0.01),治疗组与模型组比较,CWI下降(P<0.01);模型组较对照组TGF-β1及Smad3 mRNA和蛋白的表达均增多(均为P<0.01),Smad7 mRNA和蛋白表达减少(分别为P<0.01和P<0.05);治疗组与模型组比较,TGF-β1及Smad3 mRNA和蛋白表达均降低(P<0.01和P<0.05),Smad7 mRNA和蛋白表达增加(P<0.01和P<0.05)。结论 TGF-β/Smads信号通路参与了异丙肾诱导的心肌重构,阻断该通路可能是卡维地洛抑制心肌重构的机制之一。

TGF-β/Smads信号转导通路的研究进展

转化生长因子(TGF)-β超家族成员的重要生物学功能正日益引起人们的重视。受体介导的胞内信号转导研究近年有较大进展,特别是Smads蛋白介导的信号转导通路为阐明TGF-β超家族的作用机理提供了一条重要线索。TGF-β/Smads信号的转导受到机体严密的调控,并与其他信号通路存在着广泛的交叉对话效应。综述了对TGF-β/Smads信号转导通路的机制、调控,及其在维持机体正常生理功能和疾病发生中的作用的研究进展。

转化生长因子-β／Smads信号转导通路的泛素化调节在糖尿病视网膜病变中的作用

糖尿病视网膜病变（DR）是糖尿病常见和严重的并发症之一，参与的细胞因子和调节因子众多，其发病机制一直是DR防治研究的热点。研究证实，转化生长因子-β（TGF-β）参与了DR的发生和发展，Smads蛋白则能介导TGF-β／Smads信号通路的激活，进而参与DR的病理过程，而泛素一蛋白酶体途径（UPP）中的泛素连接酶Smurf则参与了TGF-β／Smads信号通路的降解调节。目前，相关研究已经取得了较大进展，就UPP对TGF-β／Smads信号转导通路的降解调节在DR中的作用进行综述。

Smads在TGF-β细胞内信号转导机制中的作用

转化生长因子 β在牙胚发育和牙髓损伤修复过程中起着非常重要的作用 ,Smads为TGF - β特异的细胞内信号转导分子家族 ,介导TGF - β对目的基因表达的调控。本文就Smads在TGF - β细胞内信号转导机制中的作用以及TGF - β/Smads信号途径与牙胚发育的关系作一综述。

TGF-β/smads信号转导通路及TGF-β_1、smad4在宫颈癌的研究

转化生长因子β(TGF-β)/smads信号转导通路在肿瘤发生机制中发挥重要作用。近年来,许多研究已经揭示了TGF-β超家族配体、受体、smad蛋白、上游和下游调节因子及多种信号通路间的交互对话在相关肿瘤中的作用机制。本文就近年关于TGF-β/smads信号转导通路及TGF-β1、smad4在宫颈癌方面的相关研究,作一简单综述。

Targeting key signalling pathways in oesophageal adenocarcinoma:A reality for personalised medicine?

Cancer treatments are rapidly changing.Curative treatment for oesophageal adenocarcinoma currently involves surgery and cytotoxic chemotherapy or chemoradiotherapy.Outcomes for both regimes are generally poor as a result of tumor recurrence.We have reviewed the key signalling pathways associated with oesophageal adenocarcinomas and discussed the recent trials of novel agents that attempt to target these pathways.There are many trials underway with the aim of improving survival in oesophageal cancer.Currently,phase 2 and 3 trials are focused on MAP kinase inhibition,either through inhibition of growth factor receptors or signal transducer proteins.In order to avoid tumor resistance,it appears to be clear that targeted therapy will be needed to combat the multiple signalling pathways that are in operation in oesophageal adenocarcinomas.This may be achievable in the future with the advent of gene signatures and a combinatorial approach.

Wulong Xiaozheng Wan medicated serum inhibits epithelial-mesenchymal transition in human gastric carcinoma cell line BGC823 by modulation of transforming growth factor-β1/Smad signaling

OBJECTIVE:To evaluate the effect of Wulong Xiaozheng Wan medicated serum on the epithelial-mesenchymal transition (EMT) of BGC823 cell induced by transforming growth factor-β,(TGF-β,) and to explore its mechanism.METHODS:EMT model of BGC823 was stimulated by TGF-β1.Wulong Xiaozheng Wan medicated serum and LY-364947 were used as intervention.The proliferation and adhesion of BGC823 were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide and flow cytometry was used to detect the apoptosis.The invasion and migration were detected by Transwell.The level of matrix metalloproteins was detected by enzyme-linked immunosorbent assay.The expressions of related proteins and mRNA of EMT marker and TGF-β1/Smad signal pathway were detected by Western blot and reverse transcription-polymerase chain reaction.RESULTS:Compared with the TGF-β1 group,Wulong Xiaozheng Wan medicated serum could inhibit the ability of proliferation,heterogeneous adhesion,invasion,and migration.It also promotes apoptosis and homotypic adhesion in BGC823,with a dose-dependent manner.Meanwhile,Wulong Xiaozheng Wan medicated serum could regulate the expression of related proteins and mRNA of TGF-β1/Smad signaling pathway,and inhibit the expressions of EMT transcription factors and EMT markers.CONCLUSION:Wulong Xiaozheng Wan medicated serum inhibited epithelial-mesenchymal transition by down-regulated the expression of TβRI and the activation of TGF-β1/Smad signaling pathway.

Shugan Huoxue Huayu Fang(疏肝活血化瘀方)attenuates carbon tetrachloride-induced hepatic fibrosis in rats by inhibiting transforming growth factor-β1/Smad signaling

OBJECTIVE:To investigate the potential mechanism by which Shugan Huoxue Huayu Fang(疏肝活血化瘀方,SGHXHYF)ameliorates liver fibrosis.METHODS:Liver fibrosis was induced in rats by intraperitoneal injection of carbon tetrachloride(CCl_(4))in peanut oil solution(40%,3 m L/kg body weight)twice a week for 8 weeks.A normal control group received the same volume of peanut oil alone.During weeks 5-8,the CCl_(4)-injected rat groups were administered saline(vehicle control),colchicine(0.1 mg/mL,1 mg/kg,positive control),or SGHXHYF(0.1 mg/mL;0.3,0.6 and 1.2 mg/kg)once daily by oral gavage.Rats were sacrificed 24 h after the last treatment.Blood samples were collected for measurement of serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),alkaline phosphatase(ALP),albumin(ALB),collagenⅠ,and collagenⅢlevels.Liver samples were analyzed by histopathological staining,Masson's staining of extracellular matrix proteins,and immune-ohistochemical staining ofα-smooth muscle actin(α-SMA).TGF-β1/Smad protein and mRNA levels were analyzed by Western blot and quantitative reverse transcription-polymerase chain reaction analysis,respectively.In vitro experiments were also performed using rat hepatic stellate cells(HSCs).RESULTS:Compared with the control animals,CCl_(4)-exposed rats exhibited elevated serum levels of ALT,AST,ALP,collagenⅠ,and collagenⅢ;reduced serum levels of ALB;and increased collagen deposition andα-SMA expression in liver sections,reflecting liver fibrosis.CCl_(4) also increased expression of TGF-β1 and the activated(phosphorylated)forms of Smad2 and Smad3 but reduced expression of the negative regulator Smad7 in the liver.Notably,concomitant administration of SGHXHYF to CCl_(4)-exposed rats was found to significantly reverse or abolish the pro-fibrotic effects of CCl_(4) in the liver and reduced serum transferase levels.Analysis of HSCs in vitro confirmed that,mechanistically,SGHXHYF inhibited activation of the TGF-β1/Smad signaling pathway by downregulating phosphorylated Smad2 and Smad3 and upregulating Smad7 levels.CONCLUSION:SGHXHYF ameliorated CCl_(4)-induced liver fibrosis by inhibiting the TGF-β1/Smad signaling pathway.These findings suggest that SGHXHYF may have clinical utility for the treatment or prevention of liver fibrosis.

Moxibustion enables protective effects on rheumatoid arthritis-induced myocardial injury via transforming growth factor beta1 signaling and metabolic reprogramming

OBJECTIVE:To examine the effects of moxibustion on myocardial injury and myocardial metabolomics in rats with rheumatoid arthritis(RA)based on the transforming growth factor beta1(TGF-β1)/Smads signaling pathway.METHODS:One hundred rats were treated with saline[normal control(NC)group]or complete Freund’s adjuvant(CFA)by right plantar injection for the RA model group,and the latter were randomly divided into 4 groups.Tripterygium wilfordii polyglycoside tablets(雷公藤多苷片,TPT)have anti-inflammatory and are widely used in the clinical treatment of RA,therefore serving as a positive control group.Three days post injection rats were given TPT tablet(TPT group),acupuncture therapy(APT group),and moxibustion treatment(MOX group)for 15 consecutive days,while NC group and model group were equally grasped and fixed and received normal saline.Rat joint swelling scores and arthritis index(AI)were evaluated in each group before the CFA challenge,therapy and after receiving therapy.Myocardial ultrastructure was observed by electron microscope.Enzyme-linked immunosorbent assay was used to detect cardiac troponin I(cTnI)levels in rat myocardial tissue.Quantitative reverse transcription polymerase chain reaction and Western blotting analysis were used to measure the mRNA and protein levels of TGF-βsignaling molecules including TGF-β1,Smad2,Smad3,Smad4,and Smad7.Myocardial metabolomics was analyzed using gas chromatography-mass spectrometer.RESULTS:Compared with model group,RA model rats receiving TPT,acupuncture,or moxibustion therapy all showed reduced joint swelling scores and AI(all P<0.01)and improved myocardial damage,whereas rats treated with moxibustion were found to be more marked.Consistently,the expressions of cTnI,TGF-β1,Smad2,Smad3,and Smad4 were found to be elevated in model rat group in contrast to NC rats and were significantly downregulated in TPT,APT and MOX group when compared with model group,while the levels of Smad7 showed the opposite result(all P<0.01).Moreover,the dissection of metabolomics suggested a novel metabolite biomarker panel including D-Xylulose 5-phosphate,dihydroxyacetone phosphate,arachidonic acid,etc was defined and implicated in amino acid,glucose,and fatty acid metabolic processes as revealed by principal component analysis and partial least squares discriminant analysis.CONCLUSION:Moxibustion prevents RA-induced inflammatory response and offers potent therapeutic effects on myocardial dysfunctions.The protective effects might be associated with its role in TGF-β1 inactivation and metabolic reprogramming.

基于TGF-β/Smads信号通路探讨苦参碱对糖尿病肾病小鼠的影响

目的研究苦参碱通过调控转化生长因子-β/信号传导蛋白(TGF-β/Smads)信号通路改善糖尿病肾病(DN)的作用及机制。方法将C57BL/6小鼠随机分为NC组、DN组、DN+苦参碱组和DN+二甲双胍组,每组10只。除NC组外,其余各组均用高脂高糖饮食加腹腔注射链脲佐菌素(STZ)的方法建立小鼠DN模型,造模成功后DN+苦参碱组灌胃给予苦参碱治疗4周,DN+二甲双胍组给予二甲双胍,DN组和NC组给予等量0.9%NaCl。用蛋白质印迹(Western blot)法检测小鼠肾组织中Ⅳ型胶原蛋白(ColⅣ)、纤连蛋白(FN)、Smad同源物2/3(Smad2/3)和磷酸化Smad2/3(p-Smad2/3)的表达水平;用生化法检测小鼠血糖、血肌酸酐和尿素氮水平。结果NC组、DN组和DN+苦参碱组小鼠血糖水平分别为(8.16±2.53)、(24.84±4.67)和(23.88±3.57)mmol·L^(-1);血肌酸酐水平分别为(36.48±5.63)、(97.51±10.59)和(41.88±7.26)mmol·L^(-1);尿素氮水平分别为(53.11±4.72)、(91.50±8.62)和(63.29±5.69)mmol·L^(-1);肾组织中ColⅣ蛋白的表达水平分别为1.00±0.19、3.34±0.58和1.99±0.44,FN蛋白的表达水平分别为1.00±0.21、3.63±0.47和1.79±0.43,p-Smad2/3/Smad2/3分别为1.00±0.18、2.74±0.51和1.08±0.33。上述指标,NC组与DN组相比,在统计学上差异均有统计学意义(均P<0.05)。结论苦参碱能够有效抑制TGF-β/Smads信号通路的激活,减少细胞外基质相关蛋白的聚积,从而发挥保护DN肾损伤的作用。

粉防己碱上调Smad7表达抑制大鼠肝星状细胞活化

目的观察低浓度粉防己碱(Tetrandrine,Tet)对培养的大鼠肝星状细胞(HSC)活化和转化生长因子β1(TGFβ1)促活化作用的影响,并探讨该作用与TGFβ1受体后信号通路的关系。方法HSC原代培养,给予Tet(0.4、0.8、1.6和3.2μmol·L-1)处理,免疫细胞化学法检测α平滑肌肌动蛋白(αSMA)表达,或给予TGFβ1(质量浓度5μg·L-1)和(或)Tet(1.6μmol·L-1)干预,分别以RTPCR和Westernblot法检测TGFβ1及其Ⅰ、Ⅱ型受体、Smad3、Smad7以及αSMAmRNA和(或)蛋白表达。结果Tet(0.4～3.2μmol·L-1)能抑制培养HSC表达αSMA。Tet(1.6μmol·L-1)抑制TGFβ1诱导的HSCαSMA表达,伴有Smad7表达上调及TGFβ1表达下降,但不影响TGFβⅠ、Ⅱ型受体和Smad3表达。结论低浓度Tet抑制培养HSC的活化和TGFβ1促活化作用,该作用与上调Smad7表达并抑制TGFβ1有关而不影响TGFβ受体表达。

Smad7对TGF-β/Smad信号转导通路的调节及其在肾纤维化中的作用

TGF- β是肾纤维化发生、发展中的必需因子 ,Smad蛋白是 TGF- β受体的胞内激酶底物 ,介导了 TGF- β的胞内信号转导。 Smad7是负反馈调节 TGF- β功能的细胞分泌因子 ,其过度表达可能改变了 R- Smads和 I- Sm ads对 TGF- β诱导纤维化的应答或阻断的病理生理平衡。深入研究 Sm ads介导的 TGF- β胞内信号转导 ,将有助于对肾脏纤维化发病机制的理解 ,为探索新的治疗途径。

经典转化生长因子β/Smad信号和Wnt/β-catenin信号间的相互作用

TGF-β信号通路是调节细胞生长和分化的的重要通路,此外还参与纤维化疾病发生和肿瘤发生发展的调控。Wnt信号通路是调节胚胎发育和肿瘤侵袭转移的重要通路。近10年来研究表明,这两条通路在调节胚胎发育、纤维化疾病发生以及肿瘤的演进等过程中共同发挥着重要作用,两者之间存在着密切联系,这两条通路存在Smad、轴蛋白(Axin)、蓬乱蛋白(Dvl)和β-连环蛋白(β-catenin)几个典型的相互作用的交叉点。本文着重阐述经典的TGF-β信号通路和Wnt信号通路在这几个交叉点的相互作用模式,以更好地应对纤维化疾病和肿瘤的进展。