Dab2 attenuates brain injury in APP/PS1 mice via targeting transforming growth factor-beta/SMAD signaling

Transforming growth factor-beta （TGF-β） type II receptor （TβRⅡ） levels are extremely low in the brain tissue of patients with Alzheimer＇s disease. This receptor inhibits TGF-β1/SMAD signaling and thereby aggravates amyolid-beta deposition and neuronal injury. Dab2, a specific adapter protein, protects T RII from degradation and ensures the effective conduction of TGF-β 1/SMAD signaling. In this study, we used an adenoviral vector to overexpress the Dab2 gene in the mouse hippocampus and investigated the regulatory effect of Dab2 protein on TGF-β1/SMAD signaling in a mouse model of Alzheimer＇s disease, and the potential neuroprotective effect. The results showed that the TβRⅡ level was lower.in APP/PS1 mouse hippocampus than in normal mouse hippocampus. After Dab2 expression, hippocampal TβRⅡ and p-SMAD2/3 levels were signifi- cantly increased, while amyloid-beta deposition, microglia activation, tumor necrosis factor- and interleulin-6 levels and neuronal loss were significantly attenuated in APP/PS1 mouse brain tissue. These results suggest that Dab2 can exhibit neuroprotective effects in Alzheimer＇s disease by regulating TGF-β1/SMAD 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.

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.

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.

Regulatory Effect of Shenge Yifei Capsule on TGF-β1/Smad Signaling Pathway in Rats with Chronic Obstructive Pulmonary Disease

[Objectives]This study aimed to study the effects of Shenge Yifei capsule on the TGF-β1/Smad signaling pathway in rats with chronic obstructive pulmonary disease(COPD).[Methods]Ten rats were randomly selected as the control group,and the other 40 rats were selected for modeling by fumigation combined with Klebsiella pneumoniae infection.A total of 38 rats were successfully modeled.They were randomly divided into model group(8 rats),low-dose Shenge Yifei capsule group(10 rats),high-dose Shenge Yifei capsule group(10 rats)and theophylline group(10 rats)in accordance with the principle of half male and half female.The rats in the model and control groups were given with distilled water by gavage,and the rats in the drug administration groups were given with corresponding drugs.The TGF-β1 level in the serum,and the expression levels of TGF-β1,Smad2,Smad3 and Smad7 and TGF-β1,Smad3 and Smad7 in airway tissues were detected.[Results]After 12 weeks,the serum TGF-β1 levels of the theophylline group and high-dose Shenge Yifei capsule group were lower than that of the low-dose Shenge Yifei capsule group(P<0.05).The expression levels of TGF-β1 and Smad3 in the theophylline group and high-dose Shenge Yifei capsule group were lower than that in the low-dose Shenge Yifei capsule group(P<0.05).The expression levels of TGF-β1 and Smad3 in the high-dose Shenge Yifei capsule group were lower than those in the low-dose Shenge Yifei capsule group and theophylline group(P<0.05).The expression levels of Smad7 and the proteins in the model group were lower than those in the other groups(P<0.05).The expression levels of Smad7 in the theophylline group and high-dose Shenge Yifei capsule group were higher than that in the low-dose Shenge Yifei capsule group(P<0.05).After 18 weeks,no significant difference was found in serum TGF-β1 level among the theophylline group and low and high-dose Shenge Yifei capsule groups(P>0.05).The expression levels of Smad7 and the proteins in the model group were lower than those in the other groups.The expression level of Smad7 in the high-dose Shenge Yifei capsule group was lower than that in the theophylline group(P<0.05).[Conclusions]Shenge Yifei capsule can regulate the TGF-β1/Smads signaling pathway.They can down-regulate the expression of TGF-β1,Smad2 and Smad3 and up-regulate the expression of Smad7,reducing the degree of airway modeling,delaying the development of COPD disease.Conventional high-dose Shenge Yifei capsule is more effective in inhibiting the expression of Smad2.

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.

Regulation Mechanism of TFP on TGF-β1/STAT3 Signaling Pathway in Immune-mediated Liver Injury in Mice

[Objectives]To study the effect of total flavonoids extracted from Polygonum perfoliatum L.(TFP)on immune-mediated liver injury induced by bacillus Calmette-Guerin plus lipopolysaccharide(BCG+LPS)in mice,and to explore its action mechanism.[Methods]60 Kunming mice were divided into normal group,model group,control group(bifendate)and TFP low,medium and high dose groups according to random number table method,with 10 mice in each group.On the first day of modeling,mice were injected with 0.2 mL of BCG solution(12.5 mg/mL)through the tail vein,and on the eleventh day,0.2 mL of LPS(37.5μg/mL)were injected into the tail vein to prepare a mouse model of immune-mediated liver injury;from the first day of modeling,the normal group and the model group were administered intragastrically with the corresponding volume of distilled water,and the bifendate group and the TFP high,medium,and low dose groups were administered intragastrically with the corresponding doses once a day for 11 d.After the last time administration,fasting but giving water for 16 h,took blood from eyes,then collected the liver tissue.The levels of alanine transaminase(ALT)and aspartate transaminase(AST)in serum were detected by biochemical method;transforming growth factor-β1(TGF-β1),intercellular adhesion molecule-1(ICAM-1),interleukin-6(IL-6)and interleukin-1β(IL-1β)expression levels in liver tissue were detected by enzyme-linked immunosorbent assay(ELISA);phosphorylated protein tyrosine kinase JAK-2(p-JAK2),phosphorylated signal transducer and activator of transcription 3(p-STAT3)protein expression levels were detected by Western Blot method;the degree of liver tissue lesions was detected by HE staining.[Results]Compared with the model group,the levels of ALT and AST in the serum of mice in each dose group of TFP(high dose 600 mg/kg,medium dose 400 mg/kg,and low dose 200 mg/kg)were reduced,and the activities of T-SOD and GSH-Px were increased;the content or expression ofβ1,ICAM-1,IL-6,IL-1βdecreased,and the expression of p-JAK2 and p-STAT3 protein decreased;pathological sections showed that the degree of inflammatory necrosis and the degree of lesions in the liver tissues of each dose group of TFP were reduced by varying degrees.[Conclusions]TFP has a protective effect on BCG+LPS-induced immune-mediated liver injury in mice.The mechanism may be related to regulating the phosphorylation level of JAK2 and inhibiting the inflammatory reaction,thereby regulating the TGF-β1/STAT3 signaling pathway and improving the immune-mediated liver injury.

TGF-β_1及其信号蛋白Smad2,3在大鼠心肌细胞肥大中的作用

目的 探讨转化生长因子 β1(transforminggrowthfactor β1,TGF β1)及其信号蛋白Smad2 ,3在诱导大鼠心肌细胞肥大中的作用。方法 培养新生大鼠心肌细胞 ,用不同剂量TGF β1刺激 ,检测 [3 H] Leu掺入量 ,RT PCR检测信号蛋白Smad2 ,3mRNA的表达。结果 不同剂量的TGF β1均能明显增加心肌细胞 [3 H] Leu掺入量 ,TGF β1增加肥大心肌细胞Smad2 ,3mRNA的表达。结论 TGF β1能诱导大鼠心肌细胞肥大 ,信号蛋白Smad2 ,3在其中发挥了重要作用。

miR-215-5p调控YY1通过TGF-β1/Smad信号通路对PCOS大鼠卵巢颗粒细胞凋亡的影响

目的探究MicroRNA-215-5p(miR-215-5p)在多囊卵巢综合征(PCOS)大鼠中的表达及其对卵巢颗粒细胞(GC)凋亡的影响,并分析潜在机制。方法采用脱氢表雄酮(DHEA)建立PCOS大鼠模型,分离并培养原代PCOS大鼠卵巢GC,分为对照组(control组)、sh-NC组、sh-YY1组、sh-YY1+LY2109761组、miR-NC组、miR-215-5p mimic组、miR-215-5p mimic+pc-NC组、miR-215-5p mimic+pc-YY1组。TUNEL法检测PCOS大鼠卵巢组织GC凋亡;实时荧光定量PCR(RT-qPCR)检测卵巢组织/GC中miR-215-5p、阴阳-1(YY1)mRNA表达;CCK-8法和平板克隆形成实验检测细胞增殖能力;流式细胞仪检测细胞凋亡率;Western blot检测PCOS大鼠卵巢组织/GC中YY1、转化生长因子-β1(TGF-β1)、Smad4蛋白表达。结果miR-215-5p在PCOS大鼠卵巢组织中低表达,YY1 mRNA和蛋白水平在PCOS大鼠卵巢组织中显著升高(P<0.05);敲低YY1或上调miR-215-5p可显著增强PCOS大鼠卵巢GC增殖能力,抑制GC凋亡,升高TGF-β1、Smad4蛋白水平(均P<0.05);TGF-β/Smad4信号通路抑制剂LY2109761可显著减弱敲低YY1对卵巢GC凋亡的抑制作用(P<0.05);在过表达miR-215-5p的基础上,上调YY1可抑制TGF-β1/Smad信号通路的激活,显著减弱miR-215-5p mimic对PCOS大鼠卵巢GC凋亡的抑制作用(P<0.05)。结论miR-215-5p在PCOS中呈低表达,过表达miR-215-5p可能通过下调YY1,激活TGF-β1/Smad信号通路,促进PCOS大鼠卵巢GC增殖并抑制其凋亡。

Yangfei Kongliu Formula, a compound Chinese herbal medicine, combined with cisplatin, inhibits growth of lung cancer cells through transforming growth factor-β1 signaling pathway

OBJECTIVE： To investigate the tumor inhibition effect of Yangfei Kongliu Formula （YKF）, a compound Chinese herbal medicine, combined with cisplatin （DDP） and its action mechanisms. METHODS： C57BL/6 mice with Lewis lung carcinoma were divided into six groups： control group （C）, DDP group （2 mg/kg, DDP）, low-dose YKF group （2.43 g/kg, L）, high-dose YKF group （24.3 g/kg, H）, low- dose YKF combined with DDP group （L ＋ DDP） and high-dose YKF combined with DDP group （H ＋ DDP）. Transforming growth factor-β1 （TGF-β1）, mothers against decapentaplegic homolog 3 （Smad3） and Smad7 levels were measured with quantitative real-time polymerase chain reaction （qPCR）, Western blotting and immunohistochemistry. An enzyme-linked immunosorbent assay was used to analyze the expressions of interleukin-2 （IL-2） and tumor necrosis factor-α （TNF-α）. RESULTS： YKF combined with DDP significantly inhibited the growth and metastasis of tumors relative to the control group, and YKF groups （P 〈 0.05）. There was no significant difference between high-dose YKF group and low-dose YKF group （P 〉 0.05）. We also found that the expression levels of TGF-β1 and Smad3 were both significantly decreased by YKF relative to the control group （P 〈 0.05）. Furthermore, after treatment with YKF combined with DDP, the expression levels of TGF-β1 and Smad3 were decreased but the expression level of Smad7 was increased relative to the DDP group （P 〈 0.05）. Compared to the DDP group, the combination of YKF and DDP enhanced the effect of tumor inhibition （P 〈 0.05）, showing obvious synergy between YKF and DDP. Treatment with DDP or YKF decreased serum levels of IL-2 and TNF-α relative to the control group （P 〈 0.05）. Furthermore, the expression levels of IL-2 and TNF-α were significantly decreased when treated with YKF in combination with DDP. Co-treatment with YKF and DDP significantly inhibited tumor growth, decreased the expressions of TGF-β1, Smad3, IL-2 and TNF-α and increased the expression of Smad7; these differences were significant relative to both YKF groups and the control group （P 〈 0.05）. CONCLUSION： YKF can inhibit tumor growth synergistically with DDP, mainly through the TGF-β1 signaling pathway.

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.

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.

THE ROLE OF CONNECTIVE TISSUE GROWTH FACTOR, TRANSFORMING GROWTH FACTOR Β1 AND SMAD SIGNALING PATHWAY IN CORNEA WOUND HEALING

The cornea is a highly specialized and unique organ in the human body. Its main function is to project light from the external environment onto the retina, and it has a specific transparency to perform its function properly. The transparency and integrity of the cornea is of vital importance. The corneal wound, especially laceration deep to Bowman＇s membrane and stroma, which will inevitably cause scar formation, may cause the degeneration or even loss of sight.

积雪草对转染TGF-β1基因的大鼠肾小球系膜细胞Smad 2/3、Smad 7和胶原蛋白Ⅳ表达的影响

目的:通过细胞转基因技术,获得稳定表达转化生长因子β1(TGF-β1)的系膜细胞(MC)克隆,观察积雪草(CA)对Smad 2/3、Smad 7和胶原蛋白1V表达及Smad 2/3磷酸化的影响。方法:采用脂质体的方法将TGF-β1表达质粒转入MC细胞,采用G418筛选并建立稳定表达TGF-β1的细胞株。将MC细胞株分为3组:对照组(未转染TGF-β1的MC+RPMI 1640+10%正常大鼠血清),TGF-β1转染组(稳定表达TGF-β1的MC+RPMI 1640+10%正常大鼠血清),积雪草(CA)组:稳定表达TGF-β1的MC+RPMI 1640+10%含高浓度CA的大鼠血清。实验重复5次。ELISA法检测各组培养上清中TGF-β1和胶原Ⅳ的含量;RT-PCR方法检测各组细胞TGF-β1、Smad 2/3、Smad7的mRNA表达水平;Western印迹法检测各组细胞TGF-β1、Smad 2/3、p-Smad 2/3、Smad 7、胶原Ⅳ的蛋白质水平。结果:TGF-β1转染组细胞上清液中的TGF-β1和胶原蛋白Ⅳ水平显著升高,积雪草能显著降低TGF-β1和胶原蛋白Ⅳ水平;TGF-β1转染组细胞中TGF-β1、Smad 2/3的mRNA和蛋白质表达水平及Smad 2/3的磷酸化水平均显著升高,而CA可显著降低MC细胞中TGF-β1、Smad 2/3的mRNA和蛋白质表达水平及Smad 2/3的磷酸化水平;TGF-β1转染组细胞中的Smad 7 mRNA水平显著降低,而CA能使Smad 7的mRNA水平显著升高。结论:稳定表达TGF-β1的MC细胞能激活TGF-β1/Smad信号通路,并引起胶原蛋白Ⅳ表达增加,而CA通过抑制此通路的激活,进而抑制胶原蛋白Ⅳ的表达而减缓糖尿病肾病(DN)的发生。

积雪草对早期糖尿病肾病大鼠TGF-β_1表达及相关下游信号的影响

目的:通过研究积雪草(CA)对早期糖尿病肾病大鼠转化生长因子β1(TGF-β1)表达及相关下游信号的影响,阐明积雪草防治早期糖尿病肾病(DN)的分子机制。方法:60只雄性SD大鼠,按体重随机分为假手术组(n=10)和造模组(n=50)。造模组大鼠进行右肾切除术,1周后给以腹腔注射链脲佐菌素(STZ)30 mg/kg,连续给3d;72 h后测血糖,以≥16.7 mmol/L,尿糖+++以上及尿量大于对照组的50%为DN模型成模标准。假手术组进行右肾被膜损伤,并注射相应量生理盐水。造模组通过灌胃给药,分为:DN模型组(模型组)、DN+福辛普利组(蒙组1.6 mg/kg·d)、DN+积雪草高剂量组(高剂量组16.8 mg/kg·d)、DN+积雪草中剂量组(中剂量组11.2 mg/kg·d)和DN+积雪草低剂量组(低剂量组5.6 mg/kg·d)(n=10),连续给药16周,每日上午1次灌胃。利用实时荧光定量PCR和Western blot分别检测肾组织中TGF-β1、TβR1、TβR2、Smad2/3、p-Smad2/3及Smad7 mRNA和蛋白的表达。结果:与假手术组相比,DN组TGF-β1、TβR1、TβR2、Smad2/3 mRNA和蛋白表达及Smad2/3蛋白的磷酸化水平显著增加(P<0.05)、Smad7 mRNA和蛋白表达明显减少(P<0.05),而福辛普利和高剂量积雪草能倒转DN引起的TGF-β1、TβR1、TβR2、Smad2/3 mRNA和蛋白表达增加(P<0.05)及Smad7 mRNA和蛋白表达降低(P<0.05)。结论:积雪草可能通过调控TGF-β1/Smad信号通路起到防治DN的作用。

RAD51相关蛋白1在宫颈癌组织中的表达及通过TGF-β/Smad通路参与调控人宫颈癌细胞的增殖和凋亡

目的:探讨RAD51相关蛋白1(RAD51AP1)通过调节转化生长因子β(TGF-β)/Smad信号通路对人宫颈癌细胞(SiHa)增殖和凋亡的影响。方法:收集2018年7月至2021年3月间南阳市中心医院51例宫颈癌组织与癌旁组织标本,免疫组织化学法检测宫颈癌组织RAD51AP1蛋白表达。筛选RAD51AP1高表达宫颈癌细胞系,体外培养SiHa细胞,分为对照组、si-RAD51AP1组(转染si-RAD51AP1质粒)、si-NC组(转染si-NC质粒)、抑制剂组(TGF-β/Smad通路抑制剂LY2109761)、si-RAD51AP1+激活剂组(转染si-RAD51AP1质粒+TGF-β/Smad通路激活剂人重组TGF-β1)。采用MTT法与平板克隆形成实验检测各组SiHa细胞增殖;流式细胞术检测细胞凋亡;实时荧光定量PCR法检测细胞中RAD51AP1、TGF-β1 mRNA水平;免疫印迹检测细胞中RAD51AP1蛋白、TGF-β/Smad通路相关蛋白及增殖、凋亡相关蛋白表达。结果:RAD51AP1在宫颈癌组织与SiHa细胞系中均显著高表达;抑制RAD51AP1表达或抑制TGF-β/Smad通路后,细胞增殖活性、细胞克隆形成率及cyclin D1、TGF-β1、p-SMAD2、p-SMAD3蛋白表达水平显著减低,细胞凋亡率、Bax、caspase-3、cleaved caspase 3蛋白表达水平显著升高,而抑制RAD51AP1表达基础上使用TGF-β/Smad通路激活剂后,可部分逆转上述变化。结论:RAD51AP1在宫颈癌中表达上调,抑制RAD51AP1表达可通过抑制TGF-β/Smad通路而抑制宫颈癌细胞增殖,促进细胞凋亡。

TGF-β_(1)/Smad信号通路与糖尿病肾病关系的研究进展

糖尿病肾病(DKD)是糖尿病的常见并发症,为终末期肾脏病的主要病因之一。DKD中糖代谢障碍所致炎症、氧化应激及糖基化终末产物等改变不同程度促使转化生长因子-β_(1)(TGF-β_(1))表达增加,加速病情进展。其中,TGF-β_(1)与其受体结合并激活下游信号蛋白发挥生物学作用。Smads蛋白作为下游信号蛋白与TGF-β_(1)组成了经典信号传导通路,参与了肾纤维化的病理过程。为进一步延缓肾纤维化进程,提升DKD治疗效果,必须全面了解TGF-β_(1)/Smad信号通路在DKD的发病机理中涉及的分子机制。因此,本文概述了TGF-β_(1)/Smad信号通路在DKD发病中的最新发现。

基于TGF-β_(1)/Smad3信号通路探讨参附注射液对缺血性脑卒中大鼠的神经保护作用

目的 基于转化生长因子β_(1)(TGF-β_(1))/Smad家族成员3(Smad3)信号通路探讨参附注射液对缺血性脑卒中(IS)大鼠的神经保护作用机制。方法 将48只无特定病原体(SPF)级SD雄性大鼠随机分为Sham组、Vehicle组、参附注射液组、TGF-β_(1)组。采用改良Longa线栓法构建Vehicle组、参附注射液组、TGF-β_(1)组大鼠永久性中动脉栓塞模型,分别腹腔注射相应剂量的生理盐水、参附注射液和TGF-β_(1),Sham组只插入线栓不结扎其余操作同Vehicle组。建模14 d后进行神经功能缺损评分;采用激光散斑成像观察大鼠大脑皮层血流变化;伊文思蓝染色检测血脑屏障通透性;2,3,5-三苯基氯化四氮唑(TTC)染色检测脑梗死面积;尼氏染色观察脑组织神经元损伤程度;原位末端凋亡检测(TUNEL)法检测细胞凋亡;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)、超氧化物歧化酶(SOD)、丙二醛(MDA)水平;蛋白免疫印迹(Western Blot)法检测TGF-β_(1)、p-Smad3、B细胞淋巴瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)表达。结果 与Sham组比较,Vehicle组大鼠大脑皮层血流灌注量、SOD水平、Bcl-2蛋白水平减少,神经功能损伤评分、脑梗死面积、血脑屏障通透性、细胞凋亡、神经元损伤、炎性因子IL-1β、IL-6、TNF-α含量、MDA水平及TGF-β_(1)、p-Smad3水平、Bax蛋白水平增加(P<0.05);与Vehicle组比较,参附注射液组和TGF-β_(1)组大鼠大脑皮层血流灌注量、SOD水平、TGF-β_(1)、p-Smad3水平、Bcl-2蛋白水平增加,神经功能损伤评分、脑梗死面积、血脑屏障通透性、细胞凋亡、神经元损伤、炎性因子IL-1β、IL-6、TNF-α表达、MDA水平、Bax蛋白水平降低(P<0.05)。结论 参附注射液可改善脑缺血大鼠血流灌注,缩小脑梗死体积,抑制机体氧化应激、炎症反应及细胞凋亡,可能通过激活TGF-β_(1)/Smad3信号通路发挥对IS大鼠神经细胞的保护作用。

Toxicarioside A,isolated from tropical Antiaris toxicaria,blocks endoglin/TGF-βsignaling in a bone marrow stromal cell line

Objective:To investigate possible mechanism of toxicarioside A in HS-5 bone stromal cells.Methods:HS-5 bone stromal cells were cultured in media supplemented with various concentrations of toxicarioside A or control DMSO(not treatment).Endoglin and TGF-βwere detected by Northern and Western blot analysis and quantified in a standard method. Downstream molecules of endoglin and TGF-β(Smad1,Smad2 and their active phosphorylated counterparts,pSmad1 and pSmad2) were also detected and quantified by Western blot analysis. In addition,cell proliferation assay and small interfering RNA(siRNA) against endoglin were used to certificate the function of endolgin in the HS-5 cells.Results:Compared with the not treated(0μg/mL) or DMSO treated control HS-5 cells,HS-5 cells treated with toxicarioside A were found significant attenuation of endolgin and TGF-βexpression.Significant inhibition of cell proliferation was also found in the HS-5 cells treated with toxicarioside A.ALK1-related Smad1 and ALK5-related Smad2 were decreased in HS-5 cells treated with toxicarioside A.In addition,phosphorylated Smad1(pSmad1) and Smad2(pSmad2) were also found attenuation in toxicarioside A-treated HS-5 cells.RNA interference showed that blockage of endoglin by siRNA also decreased Smad1 and Smad2 expression in HS-5 cells.Conclusions:Our results indicate that toxicarioside A can influence bone marrow stromal HS-5’s function and inhibit HS-5 cell proliferation by alteration of endoglin-related ALK1(Smad1) and ALK5(Smad2) signaling.

Cytokine receptor-like factor 1(CRLF1)promotes cardiac fibrosis via ERK1/2 signaling pathway

Cardiac fibrosis is a cause of morbidity and mortality in people with heart disease.Anti-fibrosis treatment is a significant therapy for heart disease,but there is still no thorough understanding of fibrotic mechanisms.This study was carried out to ascertain the functions of cytokine receptor-like factor 1(CRLF1)in cardiac fibrosis and clarify its regulatory mechanisms.We found that CRLF1 was expressed predominantly in cardiac fibroblasts.Its expression was up-regulated not only in a mouse heart fibrotic model induced by myocardial infarction,but also in mouse and human cardiac fibroblasts provoked by transforming growth factor-β1(TGF-β1).Gain-and loss-of-function experiments of CRLF1 were carried out in neonatal mice cardiac fibroblasts(NMCFs)with or without TGF-β1 stimulation.CRLF1 overexpression increased cell viability,collagen production,cell proliferation capacity,and myofibroblast transformation of NMCFs with or without TGF-β1 stimulation,while silencing of CRLF1 had the opposite effects.An inhibitor of the extracellular signal-regulated kinase 1/2(ERK1/2)signaling pathway and different inhibitors of TGF-β1 signaling cascades,comprising mothers against decapentaplegic homolog(SMAD)-dependent and SMAD-independent pathways,were applied to investigate the mechanisms involved.CRLF1 exerted its functions by activating the ERK1/2 signaling pathway.Furthermore,the SMAD-dependent pathway,not the SMAD-independent pathway,was responsible for CRLF1 up-regulation in NMCFs treated with TGF-β1.In summary,activation of the TGF-β1/SMAD signaling pathway in cardiac fibrosis increased CRLF1 expression.CRLF1 then aggravated cardiac fibrosis by activating the ERK1/2 signaling pathway.CRLF1 could become a novel potential target for intervention and remedy of cardiac fibrosis.