Effects of Tanshinone ⅡA on Transforming Growth Factor β1-Smads Signal Pathway in Renal Interstitial Fibroblasts of Rats

The effects of tanshinone ⅡA （TSN） on transforming growth factor β1 （TGFβ1） signal transduction in renal interstitial fibroblasts of rats were studied in order to investigate its mechanism in prevention of renal interstitial fibrosis. Rat renal fibroblasts of the line NRK/49F were cultured in vitro, stimulated with 5 ng/mL TGFβ1 and pretreated with 10-6, 10-5, 10-4 mol/L TSN respectively. The mRNA levels of fibronectin （FN） were examined by RT-PCR. The protein expression of FN and Smads was detected by Western blot. TGFβ1 induced the expression of FN mRNA and Smads in a time-dependent manner in a certain range. Compared with pre-stimulation, the FN mRNA and protein levels were increased by 1.1 times and 1.5 times respectively （P〈0.01, P〈0.01）, and the protein expression of phosphorylated Smad2/3 （p-Smad2/3） increased by 7 times at the end of TGFβ1 stimulation （P〈0.01）. TSN pretreatment may down-regulate the FN and p-Smad2/3 expression in a dose-dependent manner. 10-6 mol/L TSN pretreatment had no effect on the FN and p-Smad2/3 expression （both P〉0.05）. After pretreatment with 10-5 and 10-4 mol/L TSN, the FN mRNA levels were decreased by 28.1% and 43.8% respectively （P〈0.05, P〈0.01）, the FN protein levels were decreased by 40% and 44% respectively （P〈0.05, P〈0.05）, and the p-Smad2/3 protein expression were decreased by 40% and 65% respectively （P〈0.05, P〈0.01）. The inhibitory effect of TSN on renal interstitial fibrosis may be related to its blocking effect on TGFβ1-Smads signal pathway in renal intersti- tial fibroblasts.

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.

Role of transforming growth factor-beta signaling pathway in pathogenesis of benign biliary stricture

AIM: To characterize the expression of members of the transforming growth factor-beta (TGF-β)/Smad/ connective tissue growth factor (CTGF) signaling pathway in the tissue of benign biliary stricture, and to investigate the effect of TGF-β signaling pathway in the pathogenesis of benign biliary stricture. METHODS: Paraffin embedded materials from 23 cases of benign biliary stricture were analyzed for members of the TGF-β/Smad/CTGF signaling pathway. TGF-β_1, TβRⅠ, TβRⅡ, Smad4, Smad7 and CTGF protein were detected by immunohistochemical strepto-advidinbiotin complex method, and CTGF mRNA was evaluated by hybridization in situ, while 6 cases of normal bile duct served as controls. The percentages of positive cells were counted. The correlation between TGF-β_1, Smad4 and CTGF was analyzed. RESULTS: The positive expression ratios of TGF-β_1, TβRⅠ , TβRⅡ , Smad4, CTGF and CTGF mRNA in 23 cases with benign biliary stricture were 91.3%, 82.6%, 87.0%, 78.3%, 82.6% and 65.2%, respectively, signifi cantly higher than that in 6 cases of normal bile duct respectively (vs 33.3%, 16.7%, 50.0%, 33.3%, 50.0%, 16.7%, respectively, P < 0.05). The positiveexpression ratio of Smad7 in cases with benign biliary stricture was 70.0%, higher than that in normal bile duct, but this difference is not statistically signifi cant 70.0% vs 50%, P > 0.05). There was a positive correlation between positive expression of TGF-β_1, Smad4 and CTGF in cases with benign biliary stricture. CONCLUSION: The high expression of TGF-β/Smad/ CTGF signaling pathway plays an important role in the pathogenesis of benign biliary stricture.

褐藻聚合酚下调TGF-β_(1)/Smads信号通路抑制大肠癌细胞增殖与侵袭

目的探讨褐藻聚合酚(PFFE-A)对大肠癌细胞增殖与侵袭的影响,以及其对转化生长因子β_(1)(TGF-β_(1))及母体抗生物皮肤生长因子同源物2/3(Smad2/3)通路的调控作用。方法细胞分组:依次以50、100、150μmol·L-1的小、中、大剂量的PFFE-A干预细胞,另设立正常对照组细胞。5-乙炔基-2'脱氧尿苷(EdU)染色检测细胞的增殖;Transwell小室检测细胞的侵袭能力;异种种植结肠癌裸鼠模型检测细胞的体内生长与转移能力;实时荧光定量聚合酶链反应(RT-qPCR)检测细胞中上皮间质转化(EMT)相关基因的表达;Western blotting检测细胞中TGF-β_(1)、p-Smad2/3的表达水平。结果与正常对照组比较,PFFE-A小、中、大剂量组细胞的增殖率、侵袭细胞数、肿瘤瘤体质量、病灶转移比例、神经型钙黏附蛋白(N-cadherin)的mRNA的表达、TGF-β_(1)和p-Smad2/3的表达明显下降(P<0.05),E-钙黏蛋白(E-cadherin)的mRNA的表达明显升高(P<0.05),具有明显的剂量依赖性(P<0.05)。结论PFFE-A能抑制肿瘤细胞的EMT过程,抑制大肠癌细胞HT29的体外增殖与侵袭能力,下调其体内生长与转移的能力,这可能是通过下调TGF-β_(1)/Smads信号实现的。

Effects of the Nocth signaling pathway on expression of inflammatory factors and transforming growth factors in diabetic foot ulcers

Objective:persistent hyperinflammation is an important reason for the development of diabetic foot ulcer.Notch signaling is an important signaling pathway involved in the inflammatory response and cell proliferation in diabetic foot ulcer rats.This paper aims to explore the effect of Notch signaling on inflammatory factors,chemokines and growth factors through the intervention of Notch signaling in diabetic foot ulcer rats.Methods:the experimental model was made by using high-fat feed combined with streptozotocin(STZ)to cause diabetes,and the experimental model of diabetic foot ulcer was established by constant temperature and constant pressure scald apparatus.The normal ulcer model was used as a control.The intervention controls of the experimental model included normal saline,western medicine growth factor,Notch agonist Jagged1,Notch signaling inhibitor ly-411575,and the intervention of traditional Chinese medicine Zizhu ointment for 7 days.Serum il-1,il-6,TNF-radiation,and il-17 were detected by ELISA.Real-time PCR was used to detect the inflammatory factors,chemokines,and growth factors associated with Notch signaling in wound tissues:tnf-uum,il-1,il-6,il-17,interleukin-8,ip-10,McP-1,TGF-uum,TGF-livelihood.Results:serum levels of il-1,il-6,TNF-radiation and il-17 in diabetic foot ulcer rats were significantly higher than that in normal ulcer rats.The contents of il-1,il-6,TNF-radiation and il-17a in ly-411575 group and Zizhu ointment group were significantly reduced.Real-time PCR results of wound tissue showed that the levels of inflammatory cytokines il-1,il-6,TNF-radiation,il-17 and chemokines ip-10,il-8 and McP-1 in the wound tissue of diabetic foot ulcer rat model were significantly higher than that of normal ulcer model,and the levels of growth factor TGF-exposure were lower than that of normal ulcer model.LY-411575 significantly reduced il-1,il-6,TNF-maxima,il-17,and the chemokines ip-10,il-8,and McP-1 in diabetic foot ulcer rats,and reduced the expression of TGF-,TGF-earth.Jagged1 can increase the expression of TGF--,TGF---,suggesting that inhibition of the Notch signaling pathway can reduce the expression of the inflammatory factors il-1,il-6,TNF--,il-17a,il-8,and the growth factors TGF--,TGF---.Zizhu ointment can reduce the levels of il-1,il-6,TNF-benand,il-17,and the chemokines ip-10,il-8,and McP-1 on the wound surface of diabetic foot rats,and improve the expression of TGF-benand TGF-SUNS.Ly-411575 inhibited the expression of TGF-bento and TGF-promoting of Zizhu ointment.Conclusion:the expression of inflammatory cytokines and chemokines was higher and the expression of growth factors was lower in diabetic foot ulcer rats than in normal ulcer rats.Inhibition of Notch signaling pathway can reduce the expression of inflammatory factors,chemokines and growth factors in experimental model rats,and Notch signaling pathway can promote inflammation and cell proliferation.Zizhu ointment can reduce the levels of inflammatory cytokines and chemokines in diabetic foot ulcer rats,improve the expression of growth factors,and reduce wound inflammation,which may be related to the inhibition of Nocth signal expression.

Roles of Smad3 and Smad7 in rat pancreatic stellate cells activated by transforming growth factor-beta 1

BACKGROUND: Pancreatic stellate cells (PSCs) play a major role in promoting pancreatic fibrosis. Transforming growth factor beta 1 (TGF-beta 1) is a critical mediator of this process. This study aimed to determine the expression of the Smad3 and Smad7 genes in the process of PSC activation, and explore the mechanisms of chronic pancreatitis. METHODS: The expressions of Smad3 and Smad7 in PSCs before and after TGF-beta 1 treatment were detected by reverse transcription-polymerase chain reaction and Western blotting analysis. Smad3 expression was detected in PSCs after treatment with 5 ng/ml of TGF-beta 1 for 24 hours. RESULTS: Smad7 expression was decreased in TGF-beta 1 -activated PSCs (P<0.05) in a dose-dependent manner. When TGF-beta 1 concentration reached 10 ng/ml, the expression of p-Smad3, Smad3, and Smad7 was inhibited (P<0.05). CONCLUSIONS: TGF-beta 1 promotes the expression of Smad3 and inhibits the expression of Smad7 during the activation of PSCs. In contrast, high-dose TGF-beta 1 downregulates the expression of Smad3 in completely activated PSCs.

Dihydroergotamine ameliorates liver fibrosis by targeting transforming growth factor β type Ⅱ receptor

BACKGROUND The transforming growth factor β(TGFβ) signaling pathway plays a crucial role in the development of liver fibrosis by activating TGFβ type Ⅱ receptor(TGFβR2), followed by the recruitment of TGFβR1 finally triggering downstream signaling pathway.AIM To find drugs targeting TGFβR2 that inhibit TGFβR1/TGFβR2 complex formation, theoretically inhibit TGFβ signaling pathway, and thereby ameliorate liver fibrosis.METHODS Food and Drug Administration-approved drugs were screened for binding affinity with TGFβR2 by virtual molecular docking. We identified 6 candidates and further explored their potential by Cell Counting Kit-8(CCK-8) cell cytotoxic experiment to validate toxicity and titrated the best cellular working concentrations. Next, we further demonstrated the detailed molecular working mechanisms using mutagenesis analysis. Finally, we used a mouse model to investigate its potential anti-liver fibrosis effect.RESULTS We identified 6 drug candidates. Among these 6 drugs, dihydroergotamine(DHE) shows great ability in reducing fibrotic gene expressions such as collagen, p-SMAD3, and α-SMA in TGFβ induced cellular model of liver fibrosis in LX-2 cells. Furthermore, we demonstrated that DHE binds to TGFβR2. Moreover, mutation of Leu27, Phe30, Thr51, Ser52, Ile53, and Glu55 of TGFβR2 disrupted the binding of TGFβR2 with DHE. In addition, DHE significantly improved liver fibrosis, as evidenced by Masson’s trichrome staining of liver sections. This is further supported by the width and the velocity of the portal vein, and serum markers of liver function. In line with those observations, DHE also decreased macrophages infiltration and extracellular matrix deposition in the liver.CONCLUSION DHE alleviates liver fibrosis by binding to TGFβR2 thereby suppressing TGFβ signaling pathway. We show here that as far as drug repurposing, DHE has great potential to treat liver fibrosis.

活血利水复方对自发性高血压大鼠转化生长因子-β1/SMAD家族蛋白信号通路介导下游结缔组织生长因子及Ⅰ、Ⅲ型胶原表达及血管重塑的影响

目的:基于转化生长因子-β1/SMAD家族蛋白信号通路探讨活血利水中药复方对自发性高血压大鼠血管重塑的保护作用及机制。方法:将自发性高血压大鼠随机分为模型组、卡托普利组、活血利水复方低剂量组、活血利水复方中剂量组、活血利水复方高剂量组,Wistar大鼠作为空白组,每组10只。给予相应药物灌胃,4周后采用酶联免疫吸附试验方法检测血清中C反应蛋白、肿瘤坏死因子-α、白细胞介素-6的含量;采用逆转录聚合酶链反应检测大鼠主动脉组织转化生长因子-β1、结缔组织生长因子及Ⅰ型胶原、Ⅲ型胶原mRNA表达,并取冠状动脉组织进行马松三色染色。结果:与空白组比较,模型组血清中C反应蛋白、肿瘤坏死因子-α、白细胞介素-6的含量显著升高(P<0.01);与模型组比较,各药物组大鼠干预后血清中C反应蛋白、肿瘤坏死因子-α、白细胞介素-6的含量不同程度降低(P<0.01)。其中,卡托普利组和活血利水复方高剂量组上述3项指标表达最低,与其他组的差异有统计学意义(P<0.05或P<0.01);卡托普利组和活血利水复方高剂量组比较,差异无统计学意义(P>0.05)。与空白组比较,模型组大鼠主动脉转化生长因子-β1、结缔组织生长因子及Ⅰ型胶原、Ⅲ型胶原mRNA表达显著升高(P<0.01);与模型组比较,卡托普利组及活血利水复方低剂量组、活血利水复方中剂量组、活血利水复方高剂量组大鼠主动脉组织转化生长因子-β1、结缔组织生长因子及Ⅰ型胶原、Ⅲ型胶原mRNA表达不同程度降低(P<0.05或P<0.01)。结论:活血利水中药复方可通过调控转化生长因子-β1/SMAD家族蛋白信号通路及下游结缔组织生长因子及Ⅰ型胶原、Ⅲ型胶原mRNA表达水平,降低C反应蛋白、肿瘤坏死因子-α、白细胞介素-6等炎症因子的表达,抑制炎症反应,从而改善高血压病炎症状态及血管重塑,其机制可能与降低转化生长因子-β1、结缔组织生长因子及Ⅰ型胶原、Ⅲ型胶原蛋白沉积有关。

Effect of Tuina along“bladder meridian”alleviating intervertebral disc degeneration by regulating the transforming growth factor-β1/Smad signaling pathway in a rabbit model

OBJECTIVE:The aim of this study was to investigate the protective effects of Tuina(a traditional Chinese massage therapy)on intervertebral disc(IVD)degeneration and the regulatory mechanisms of the transforming growth factor-β1(TGF-β1)/small mothers against decapentaplegic(Smad)signaling pathway.METHODS:Thirty New Zealand white rabbits were randomized into five groups:the control group,model group,model+Tuina group(Tuina group),model+TGF-β1 group(TGF-β1 group),and model+TGF-β1 inhibitor SB431542 group(SB431542 group).The model was established by posterolateral annulus fibrosus puncturing(AFP).Recombinant TGF-β1 and inhibitor SB431542 was injected into the TGF-β1 group and SB431542 group with a microsyringe,respectively.The rabbits in the Tuina group received Tuina treatment along the bladder meridian for 4 weeks.Magnetic resonance imaging(MRI)was performed on rabbits before AFP and after 4 weeks of intervention.Lumbar IVDs(L2-L3 to L4-L5)were harvested after intervention.Histopathological changes in the IVDs were measured by hematoxylin and eosin(HE)staining.Type I collagen was analyzed by immunohistochemistry detection.The expression level of matrix metalloproteinase-3(MMP3)was determined by enzyme-linked immunosorbent assay.Cell apoptosis was evaluated by terminal deoxynucleotidyl transferasemediated nick end labeling and Western blotting.Realtime polymerase chain reaction and Western blotting were used to analyze the expression of TGF-β1 and Smad2/3/4 and a disintegrin and metalloproteinase with thrombospondin motifs 5.RESULTS:Posterolateral AFP induced IVD degeneration in rabbits with histopathological damage and noticeable changes in MRI images.Tuina alleviated histopathological changes and reversed the expression of extracellular matrix degeneration-related molecules and apoptosis-related proteins.Furthermore,AFP induced the activation of TGF-β1 and Smad2/3/4,whereas Tuina therapy markedly reduced the protein expression of Smad2/3 and the gene expression of TGF-β1 and Smad2/3/4.Additionally,the TGF-β1/Smad signaling pathway was activated in the TGF-β1 group,while the TGF-β1/Smad signaling pathway was inhibited in the SB431542 group.CONCLUSION:Posterolateral AFP induced disc degeneration as determined by MRI assessment and histological analysis.Tuina alleviated disc degeneration,possibly by inhibiting the fibrotic response mediated by the TGF-β1/Smad pathway,thus alleviating extracellular matrix degeneration and reducing cell apoptosis.

Interaction between insulin-like growth factor binding protein-related protein 1 and transforming growth factor beta 1 in primary hepatic stellate cells

BACKGROUND: We previously showed that insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) is a novel mediator in liver fibrosis. Transforming growth factor beta 1 (TGF beta 1) is known as the strongest effector of liver fibrosis. Therefore, we aimed to investigate the detailed interaction between IGFBPrP1 and TGF beta 1 in primary hepatic stellate cells (HSCs). METHODS: We overexpressed TGF beta 1 or IGFBPrP1 and inhibited TGF beta 1 expression in primary HSCs for 6, 12, 24, 48, 72, and 96 hours to investigate their interaction and observe the accompanying expressions of a-smooth muscle actin (alpha-SMA), collagen I, fibronectin, and phosphorylated-mothers against decapentaplegic homolog 2/3 (p-Smad2/3). RESULTS: We found that the adenovirus vector encoding the TGF beta 1 gene (AdTGF beta 1) induced IGFBPrP1 expression while that of alpha-SMA, collagen I, fibronectin, and TGF beta 1 increased gradually. Concomitantly, AdIGFBPrP1 upregulated TGF beta 1, alpha-SMA, collagen I, fibronectin, and p-Smad2/3 in a time-dependent manner while IGFBPrP1 expression was decreased at 96 hours. Inhibition of TGF beta 1 expression reduced the IGFBPrP1-stimulated expression of alpha-SMA, collagen I, fibronectin, and p-Smad2/3. CONCLUSIONS: These findings for the first time suggest the existence of a possible mutually regulation between IGFBPrP1 and TGF beta 1, which likely accelerates liver fibrosis progression. Furthermore, IGFBPrP1 likely participates in liver fibrosis in a TGF beta 1-depedent manner, and may act as an upstream regulatory factor of TGF beta 1 in the Smad pathway.

The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes

We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis.

Feedback regulation between phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1 and transforming growth factor β1 and prognostic value in gastric cancer

BACKGROUND Phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1(PREX1)was reported to be overexpressed in some cancers and involved in cancer development,but its expression and significance in gastric cancer remain unclear.AIM To evaluate the expression of PREX1 in gastric cancer and its significance in the development of gastric cancer,especially to evaluate the potential mechanism of PREX1 in gastric cancer.METHODS Bioinformatic analysis was performed in order to examine the expression of PREX1 in gastric cancer.The relationship between the survival rate of gastric cancer patients and PREX1 expression was assessed by Kaplan Meier portal.The Gene Set Enrichment Analysis and the correlation between PREX1 and transforming growth factor(TGF)β1 pathway-related mediators were evaluated by cBioPortal for Cancer Genomics.Western blotting and reverse transcriptase polymerase chain reaction assay were used to test the role of TGFβ1 on the expression of PREX1.Western blotting and dual-luciferase reporter system was used to evaluate the effect of PREX1 on the activation of TGFβ1 pathway.Wound healing and Transwell assay were used to assess the effect of PREX1 on the metastasis activity of gastric cancer cells.RESULTS PREX1 was overexpressed in the gastric tumors,and the expression levels were positively associated with the development of gastric cancer.Also,the high expression of PREX1 revealed poor prognosis,especially for those advanced and specific intestinal gastric cancer patients.PREX1 was closely involved in the positive regulation of cell adhesion and positively correlated with TGFβ1-related mediators.Furthermore,TGFβ1 could induce the expression of PREX1 at both the protein and mRNA level.Also,PREX1 could activate the TGFβ1 pathway.The induced PREX1 could increase the migration and invasion activity of gastric cancer cells.CONCLUSION PREX1 is overexpressed in gastric cancer,and the high level of PREX1 predicts poor prognosis.PREX1 is closely associated with TGFβsignaling and promotes the metastasis of gastric cancer cells.

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.

大蒜素通过部分阻抑TGF-β_1介导的Smads信号改善压力超负荷大鼠心肌反应性纤维化

目的研究大蒜素是否通过TGFβ-Smads信号通路改善压力超负荷大鼠心肌纤维化。方法 40只SD雄性大鼠随机分为假手术组、模型组、大蒜素组和川芎嗪组,每组10只。以腹主动脉缩窄方法制备压力超负荷心肌肥厚大鼠模型。造模后3天,大蒜素组和川芎嗪组分别给予大蒜素注射液5.0mg/kg、盐酸川芎嗪注射液20mg/kg腹腔注射,假手术组和模型组给予生理盐水腹腔注射。给药4周后,天狼猩红染色观察心肌胶原变化,计算心肌胶原容积分数(myocardial collagen volume fraction,CVF)和血管周围胶原面积(perivascular collagen area,PVCA);ELISA法检测血清转化生长因子-β1(transforming growth factor-β1,TGF-β1)水平;免疫组化法观察心肌组织TGF-β1蛋白表达;实时荧光定量PCR检测心肌Smad2和Smad7 mRNA表达量的变化;荧光素酶报告基因检测进一步验证大蒜素对TGF-β信号传导系统的影响。结果与假手术组比较,模型组大鼠心肌CVF、PVCA、血清TGF-β1水平及心肌组织TGF-β1蛋白表达均明显增加(P<0.05,P<0.01);与模型组比较,大蒜素组和川芎嗪组PVCA、血清TGF-β1水平及心肌组织TGF-β1蛋白表达均明显减少(P<0.05,P<0.01)。模型组Smad2 mRNA表达上调而Smad7mRNA表达下调,大蒜素组和川芎嗪组Smad2 mRNA表达明显下调(P<0.05),川芎嗪组Smad7 mRNA表达明显上调(P>0.05)。在2ng/mLTGF-β1干预下,1～2μg/mL大蒜素可以明显抑制相应TGF-β1的荧光素酶活性(P<0.05)。结论大蒜素通过部分阻抑TGFβ1介导的Smad信号减轻压力超负荷大鼠的心肌反应性纤维化。

TGF-β_1介导的Smads与ERK通路在肺纤维化中的作用及相互关系

丝裂原活化蛋白激酶(MAPK)是体内四大信号转导系统之一,已发现p38、ERK5/BMK1、ERK及JNK/SAPK4个亚族。它参与介导生长、发育、分裂、分化、死亡及细胞间功能同步等多种细胞过程,其中ERK通路在肺成纤维细胞(FB)增殖过程中起着非常重要的作用。在肺纤维化(pulmonaryfibrosis)的进程中,转化生长因子β-1(TGF-β1)介导的Sma-andMAD-related(Smad)与ERK通路,通过对FB等细胞的作用、对多种炎症因子生成的调控以及促进转录因子活化等机制来调节纤维化过程的发生发展。该文就Smads和ERK通路在肺纤维化发病中的作用及两条通路之间的相互关系作一综述。

丹参酮ⅡA对高血压大鼠肥厚心肌TGF-β_1/Smads信号通路的影响

目的研究丹参酮(Tanshinone,TSN)ⅡA对压力超负荷大鼠肥厚心肌血管紧张素1型受体(angiotensin Ⅱtype 1 receptor,AT1R)、转化生长因子β1(transforming growth factor-β1,TGF-β1)与其胞内信号蛋白Smads基因表达的影响,探讨TSNⅡA抑制高血压左心室肥厚的分子机制。方法 SD大鼠行腹主动脉缩窄术建立高血压左室心肌肥厚模型,术后4周将手术大鼠随机分为模型组、丹参酮低、高剂量组[10、20mg/(kg.d)]、缬沙坦组[10mg/(kg.d)],每组8只;另有8只作为假手术组。用药8周后检测各组尾动脉压,取左心室组织检测左心室质量指数(left ventricular mass index,LVMI)、病理切片HE染色测量心肌纤维直径(myocardial fiber dimension,MFD);采用逆转录-聚合酶链式反应(reverse transcription-polymerase chain raction,RT-PCR)检测AT1R mRNA的表达水平,免疫印迹法(Western blot)分别检测TGF-β1及其胞内信号蛋白Smad-3、4、7的蛋白水平。结果 (1)丹参酮低、高剂量组血压没有变化,并显著高于假手术组和缬沙坦组(P<0.01)。(2)丹参酮低、高剂量组和缬沙坦组的LVMI、MFD均显著低于模型组(P<0.01)。(3)心肌肥厚时AT1R、TGF-β1和Smad-3的表达显著增加(P<0.01),高剂量TSNⅡA和缬沙坦都可使肥厚心肌的AT1R mRNA和TGF-β1、Smad-3蛋白水平明显下调(P<0.01),缬沙坦对TGF-β1的下调作用较丹参酮明显(P<0.05)。(4)低、高剂量的丹参酮和缬沙坦均可以使Smad-7蛋白的表达显著上调(P<0.01),丹参酮高剂量组上调作用明显超过缬沙坦组(P<0.05)。结论丹参酮ⅡA对心肌肥厚的抑制作用是非血压依赖性的,其对高血压心肌肥厚的抑制作用可能与抑制AT1R mRNA表达、阻滞TGF-β1/Smads的信号转导有关。

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。

芪蛭降糖胶囊对糖尿病肾病大鼠肾组织BMP-7及TGF-β_1/smads信号传导通路的影响

目的：观察芪蛭降糖胶囊对糖尿病肾病（diabetic nephropathy,DN）大鼠肾组织骨形成蛋白-7（bone morpho-genetic protein-7,BMP-7）及转化生长因子（transforming growth factor,TGF）-β1/Smads信号传导通路的影响。方法：48只清洁级雄性Wistar大鼠按体重随机抽取40只,采用切除右肾加腹腔注射链脲菌素（ streptozotocin,STZ）的方法制备DN模型,另外8只大鼠行右肾假切术。造模成功后按尿微量白蛋白（ microAlbumin,mAlb）高低,两头随机抽取分为模型组、缬沙坦对照组、芪蛭降糖胶囊低剂量组、芪蛭降糖胶囊高剂量组。成模2 d起各组给予相应浓度和剂量的药物,给药12周时观察DN大鼠尿mAlb、α1微球蛋白（α1-MG）和血清肌酐（ Scr）、尿素氮（ BUN）。然后,处死所有动物,肾组织行HE染色、PAS染色和Masson染色,观察肾组织病理变化并半定量计算肾小管损伤指数（tubulointerstitial injury index,TII）,免疫组化法检测BMP-7、TGF-β1、Smad2、Smad7在肾组织的表达。结果：给药12周后,模型组大鼠尿 mAlb、α1-MG较假手术组显著增多（ P 〈0.01）,3个治疗组DN大鼠尿mAlb、α1-MG较模型组明显减少（P〈0.01）,2个中药治疗组的上述4项指标亦较对照组降低（P〈0.05-0.01）,且呈剂量依赖性。模型组大鼠Scr、BUN亦较假手术组显著升高（P〈0.01）,对照组与模型组相比无明显变化（P〉0.05）,但2个中药治疗组较模型组明显降低（P〈0.05-0.01）。 HE染色显示,3个治疗组大鼠肾组织病理损害明显减轻,2个中药治疗组大鼠肾组织病理改善比对照组更明显；PAS染色进行TII评分发现,3个治疗组大鼠TII显著低于模型组（P〈0.01）,2个中药治疗组TII明显低于对照组（P〈0.05-0.01）；Masson染色观察发现,3个实验组大鼠肾小管间质病变明显轻于模型组,2个中药治疗组大鼠肾小管间质病变轻于对照组；免疫组化法染色并对其灰度值测定发现,3个治疗组大鼠TGF-β1、Smad2在肾组织的表达低于模型组（P〈0.01）,2个中药治疗组大鼠TGF-β1、Smad2在肾组织的表达低于对照组（P〈0.05-0.01）；3个治疗组大鼠BMP-7、Smad7在肾脏组织的表达高于模型组（P〈0.01）,2个中药治疗组大鼠BMP-7、Smad7在肾组织的表达高于对照组（P〈0.05-0.01）。结论：芪蛭降糖胶囊可能通过干预BMP-7/TGF-β1/Smads信号转导通路抑制了TGF-β1信号的细胞内转导,而对DN肾间质纤维化起到治疗作用。

BMP-7/Smads/TGF-β_1信号转导通路与肾间质纤维化

肾间质纤维化导致多种肾脏疾病发展至终末期肾衰竭,TGF-β1/Smads信号通路是肾脏纤维化重要的转导通路。骨形态发生蛋白7(BMP-7)不仅影响TGF-β1/Smads通路的信号转导,还与TGF-β1存在互逆作用,可多方面抵消TGF-β1的促肾纤维化作用。现就BMP-7/Smads/TGF-β1信号转导通路与肾间质纤维化的关系进行综述。

加味当归补血汤对肾小管上皮细胞TGF-β_1/SMADs信号转导通路的影响

目的：观察加味当归补血汤对转化生长因子β1（TGF-β1）刺激的小鼠肾小管上皮细胞Smad3、Smad4、Smad7信号通路的影响，探讨该方防治肾间质纤维化的细胞分子生物学机制。方法：原代培养BalB／C小鼠肾小管上皮细胞．用TGF-β（1ng／ml）刺激24h，加味当归补血汤及洛汀新含药血清干预。共分6组：正常组、模型组、加味当归补血汤低中高剂量组（含药血清浓度分别为2．5％、5％、10％）、洛汀新组，观察各组细胞形态学变化，检测细胞Smad3、Smad4、Smad7的mRNA和蛋白质表达情况（PT—PCR、Western-Blotting）。结果：（1）TGF-β1刺激后，肾小管上皮细胞部分形态发生变大，伸长，呈梭形，经中药加味当归补血汤和洛汀新干预后，细胞形态又恢复正常；（2）TGF-β1刺激肾小管上皮细胞后，Smad3、Smad4 mRNA和蛋白质表达显著增加，Smad7 mRNA和蛋白质则显著减少（P〈0、05～0、01）；（3）各浓度加味当归补血汤能显著下调异常增高的Smad3，上调Smad7的基因和蛋白质表达水平（P〈0．05～0．01），能显著下调Smad4基因表达。结论：加味当归补血汤防治肾间质纤维化可能与调控肾小管上皮细胞TGF-β1／Smads信号转导途径相关。