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.

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.

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.

Neuron-like differentiation of adult rat bone marrow stromal cells induced by transforming growth factor-beta and brain-derived neurotrophic factor

BACKGROUND： It has been demonstrated that transforming growth factor-β （TGF-β） and brain- derived neurotrophic factor （BDNF） can induce stem cell differentiation into neuron-like cells. OBJECTIVE： To investigate the efficacy of TGF-β and BDNF at inducing the differentiation of adult rat bone marrow stromal cells （BMSCs） into neuron-like cells, both in combination or alone. DESIGN, TIME AND SETTING： A comparative observation experiment was performed at the Department of Orthopedics, First Affiliated Hospital of Liaoning Medical University between October 2007 and January 2008. MATERIALS： TGF-~ and BDNF were purchased from Sigma, USA; mouse anti-rat neuron specific enolase, neurofilament and glial fibrillary acidic protein were purchased from Beijing HMHL Biochem Ltd., China. METHODS： BMSCs were isolated from rats aged 4 weeks and incubated with TGF-β（1μ g/L） and/or BDNF （50 μ g/mL）. MAIN OUTCOME MEASURES： Expression of neuron-specific enolase, neurofilament and glial fibrillary acidic protein were determined by immunocytochemistry. RESULTS： BMSCs differentiated into neuron-like cells following induction of TGF-β and BDNF, and expressed both neuron-specific enolase and neurofilament. The percent of positive cells was significantly greater in the combination group than those induced with TGF-β or BDNF alone （P 〈 0.01）. CONCLUSION： Treatment of BMSCs with a combination of TGF-β and BDNF induced differentiation into neuron-like cells, with the induction being significantly greater than with TGF-β or BDNF alone.

Immunohistochemical demonstration of transforming growth factor－β and bone morphogenetic protein in salivary gland tumors

Transforming growth factor-β (TGF-β) and bone morphogenetic protein (BMP)were related to embryonic development and the differentiation of many types of cells. Recent studies showed that they might play an important role in regulating the differentiation o

Glycine Attenuates Myocardial Fibrosis in Myocardial Infarction in Rats Partly through Modulating Signal Transducer and Activator of Transcription 3/Nuclear Factor-κB/Transforming Growth Factor-β axis

Objective: Inflammation and fibrosis are strongly associated with each other. Glycine is present in various traditional Chinese medicines and exhibits anti-inflammatory activity. However, the effects of glycine on myocardial fibrosis(MF) in rats with myocardial infarction(MI) have not been reported. The purpose of this study is to investigate the effects of glycine therapy on MF and comprehend its underlying mechanisms. Materials and Methods: Left anterior descending artery ligation-induced MI in Sprague Dawley rats was leveraged to assess the therapeutic effects of Glycine. Rats received either normal saline or glycine(0.5 mg/g bodyweight) for 7 days. Results: Glycine upregulated cardiac ejection fraction and fractional shortening to improve cardiac function, as evaluated by echocardiography. Histological and immunohistochemical analyses demonstrated that glycine could decrease inflammatory cell infiltration and alleviate collagen deposition. Western blotting revealed that nuclear factor-κB(NF-κB)-mediated inflammatory signaling was also downregulated by glycine treatment. The expression of signal transducer and activator of transcription 3(STAT3), tumor necrosis factor-α, and transforming growth factor-β(TGF-β) was decreased significantly in the glycine-treated group compared to the model group. Thus, glycine plays a protective role against myocardial ischemia and subsequent MF. Conclusion: The protective effects of glycine were achieved partly through STAT3/NF-κB/TGF-β signaling pathway.

Roles of transforming growth factor-βsignaling in liver disease

In this editorial we expand the discussion on the article by Zhang et al published in the recent issue of the World Journal of Hepatology.We focus on the diagnostic and therapeutic targets identified on the basis of the current understanding of the molecular mechanisms of liver disease.Transforming growth factor-β(TGF-β)belongs to a structurally related cytokine super family.The family members display different time-and tissue-specific expression patterns associated with autoimmunity,inflammation,fibrosis,and tumorigenesis;and,they participate in the pathogenesis of many diseases.TGF-βand its related signaling pathways have been shown to participate in the progression of liver diseases,such as injury,inflammation,fibrosis,cirrhosis,and cancer.The often studied TGF-β/Smad signaling pathway has been shown to promote or inhibit liver fibrosis under different circumstances.Similarly,the early immature TGF-βmolecule functions as a tumor suppressor,inducing apoptosis;but,its interaction with the mitogenic molecule epidermal growth factor alters this effect,activating anti-apoptotic signals that promote liver cancer development.Overall,TGF-βsignaling displays contradictory effects in different liver disease stages.Therefore,the use of TGF-βand related signaling pathway molecules for diagnosis and treatment of liver diseases remains a challenge and needs further study.In this editorial,we aim to review the evidence for the use of TGF-βsignaling pathway molecules as diagnostic or therapeutic targets for different liver disease stages.

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

We reported in this manuscript that TGF-β1 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-β1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-β1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-β1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-β1-mediated gene expression and apoptosis.

Modified Xiaochaihu Decoction(小柴胡汤)Prevents the Progression of Chronic Pancreatitis in Rats Possibly by Inhibiting Transforming Growth Factor-β 1/Sma-and Mad-Related Proteins Signaling Pathway

Objective： To investigate the effect of modified Xiaochaihu Decoction （小柴胡汤, MXD） on transforming growth factor- [3 1/Sma- and Mad-related proteins （TGF- 13 1/Smads） signaling pathway in rats with chronic pancreatitis （CP） induced by dibutyltin dichloride. Methods： Thirty healthy male Wistar rats were randomly divided into the normal control group, CP group and CP＋MXD-treated group. CP was induced by injection of dibutyltin dichloride （DBTC, 7 mg/kg of body weight） into the right caudal vein, and the control rats were treated with vehicle. MXD was given daily by gavage at a dose of 10 g/kg of body weight, starting from the day after CP induction. After 28-day treatment, the n-benzoyl-tyrosyl para-aminobenzoic acid （NBT-PABA） test was carried out to evaluate exocrine pancreatic function. Then, rats were sacrificed, and pancreatic tissues were harvested for histological evaluation. In addition, the mRNA expression of TGF- β 1, TGF- β 1 type Ⅱ receptor （TGF β R 11 ）, Smad3 and Smad7 was determined in pancreatic tissues by using real-time polymerase chain reaction. Results： Treatment of CP with MXD improved the PABA recovery, decreased the histological lesion, and reduced the mRNA expression of TGF- β 1, TGF β R 11 and Smad3 （P〈0.05）. However, MXD had no effect on Smad7 mRNA level. Conclusions： MXD could protect the pancreas against chronic injury and improve pancreatic exocrine function in DBTC induced rat CP model. Its mechanism may involve inhibition of the TGF-β 1/Smads signaling pathway.

Expression of c-erbB-2 oncogene protein, epidermal growth factor receptor, and TGF-β1 in human pancreatic ductal adenocarcinoma

Objective: To detect the relations of c-erbB-2 onco-gene protein, epidermal growth factor receptor (EG-FR) and transforming growth factor-β1 (TGF-β1)to the progression or metastasis of pancreatic carci-noma.Methods: Using streptavidinbiotin complex (SABC)method, c-erbB-2 oncongene protein, we examinedimmunohistochemically EGFR and TGF-β1 expres-sions in wax-tissue sections from 10 individuals withnormal pancreas (NP), 13 patients with chronic pan-creatitis (CP) and 36 patients with pancreatic ductaladenocarcinoma (PC).Results: The positive expression rates of c-cerbB-2oncogene protein, EGFR and TGF-β1 in the NP, CPand PC groups were 0, 0, 10%; 7.7%, 7.7%,7.7%; and 41.7%, 50.0%, 44.4%, respectively.The positive expression rates of the three specific pro-teins increased more significantly in the PC groupthan in the NP and CP groups (P【0.05). The indi-vidual expression of c-erbB-2, EGFR and TGF-β1was not related to the age and sex of the patients aswell as the site, size and histopathological grade oftumors (P】0.05), but to the clinical stage of tumors(P【0.01). The coexpression rate of the three pro-teins was 27.8 % (10/36). This coexpression in thePC group was correlated with the histopathologicalgrades and clinical stages of tumors (P【0.01).Conclusion: Detection of c-erbB-2 oncogene protein,EGFR, and TGF-β1 expressions in pancreatic tissueis helpful to judge the malignancy, progression, andmetastasis of PC.

Huangqi decoction(黄芪汤) attenuates renal interstitial fibrosis via transforming growth factor-β1/mitogen-activated protein kinase signaling pathways in 5/6 nephrectomy mice

OBJECTIVE: To investigate the effect of Huangqi decoction( 黄芪汤) on renal interstitial fibrosis and its association with the transforming growth factor-β1(TGF-β1)/mitogen-activated protein kinase(MAPK) signaling pathway. METHODS: 120 C57/BL mice were randomly divided into six groups: sham group, Enalapril(20 mg/kg) group, 5/6 nephrectomy model group, and 5/6 nephrectomy model plus Huangqicoction(0.12, 0.36 and 1.08 g/kg respectively) groups. Detecting 24hours urinary protein, blood pressure, serum creatinine, urea nitrogen content changes. Periodic Acid-Schiff stain(PAS) and Masson’s trichrome staining was used to observe the renal tissue pathological changes. Protein expression of TGF-β1, Phosphorylated P38 mitogen activated protein kinases(P-P38), Phosphorylated c-jun N-terminal kinase(P-JNK), Phosphorylated extracellular regulated proteinhnase(PERK), Fibroblast-specific protein-1(FSP-1), Alpha smooth muscle actin(α-SMA), Type Ⅲ collagen(Collagen Ⅲ), Connective tissue growth factor(CTGF),Bcl-2 Assaciated X protein(Bax) and B cell lymphoma 2(Bcl-2) were measured with western blot and immunohistochemical. RESULTS: Both Huangqi decoction and Enalapril improved the kidney function, 24 h urinary protein and the fibrosis in 5/6 nephrectomy mice, Huangqi decoction downregulated the expressions of TGF-β1, FSP-1, α-SMA, Collagen Ⅲ and CTGF in a dose-dependent manner, and it has a significant difference(P < 0.01) compared with model group.Huangqi decoction downregulated the expressions of P-P38, P-JNK, P-ERK and Bcl-2 in a dose-dependent manner, while upregulated the expression of Bax. CONCLUSIONS: The protective effect of Huangqi decoction for renal interstitial fibrosis in 5/6 nephrectomized mice via the inhibition of EpithelialMesenchymal Transitions and downregulating the TGF-β1/MAPK 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.

Effectiveness of conjunctival bleb scarring by knockdown of heat shock protein 47 in rat model

AIM:To evaluate the effectiveness of knock-down of heat shock protein 47(HSP47)on conjunctival bleb scarring in a rat model and its possible mechanism.METHODS:Male Sprague–Dawley rats were used for glaucoma filtration surgery(GFS)and were treated with either phosphate buffered solution,shControl,mitomycin C,or sh-HSP47 using a microsyringe immediately after GFS.The morphology of filtering blebs was observed postoperatively.The levels of HSP47 were analyzed at 2,5,8,and 11d after GFS via real‑time quantitative polymerase chain reaction(PCR)and Western blot.The silencing effect of HSP47,the expression of collagen I and III,and the potential signaling pathways of HSP47 during scarification were explored 11d post GFS.The protein levels of transforming growth factor-β1(TGF-β1),phospho-Smad2(pSmad2),phospho-Smad3(p-Smad3),and phospho-p38(p-p38)were also analyzed using Western blot.RESULTS:Sh-HSP47 treatment significantly prolonged the functional filtration bleb retention.The levels of HSP47 were increased significantly at 5,8,and 11d postoperatively compared to the control group(P<0.05,P<0.01,and P<0.001).The levels of HSP47 protein at day 11 postoperatively were significantly down-regulated after HSP47 silencing using sh-HSP47 adenovirus transfection(P<0.01).Expression levels of collagen I and III within the blebs were significantly reduced in the absence of HSP47(P<0.01).Moreover,the protein levels of TGF-β1,p-Smad2/3,and p-p38 were dramatically inhibited after treatment with sh-HSP47(P<0.01).CONCLUSION:The inhibitory effects of HSP47 knockdown on scarring after GFS have the potential to be an efficacious therapeutic option for the treatment of conjunctival bleb scarring.

植物异三聚体G蛋白研究进展

植物细胞中的异三聚体G蛋白信号转导系统包括异三聚体G蛋白、G蛋白偶联受体、类受体激酶、G蛋白信号调节因子等,这些信号转导组分在感受物理及化学刺激、启动细胞内信号级联反应、调控细胞内代谢和基因表达过程中发挥重要作用.异三聚体G蛋白参与调控植物生长发育(如胚胎形成、营养器官生长、有性生殖等)、植物对生物及非生物胁迫的响应、根瘤形成等过程.因此,异三聚体G蛋白信号系统组分参与调控多种农作物的农艺性状,并最终影响农产品的产量和品质.对植物异三聚体G蛋白的结构、活化机制和生理功能等方面近年来取得的研究进展进行了回顾和总结.

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.

TGF-β信号通路在骨髓增生异常综合征中作用机制的研究进展

骨髓增生异常综合征(MDS)是一种细胞遗传学与分子遗传学高度异质性的恶性克隆性疾病,且进展为急性髓系白血病(AML)的风险极高。转化生长因子-β(TGF-β)与MDS的发病密切相关,是免疫稳态及免疫耐受的关键执行者,可抑制免疫系统许多组成部分的扩张和功能。TGF-β信号通路能调控微环境中的造血细胞及免疫细胞,抑制其发挥正常生物学功能,从而加快MDS的疾病进展。就近年来TGF-β信号通路对MDS红细胞、T淋巴细胞、自然杀伤细细胞、巨噬细胞的调控作用进行综述,以期为MDS的发病机制及治疗提供新的视角。

SOX9通过转化生长因子β信号通路调节角膜内皮损伤后内皮-间质转化过程

目的探究性别决定区Y框蛋白9(sex-determining region Y-box protein 9,SOX9)是否会调控角膜内皮细胞损伤后的角膜上皮-间质转化(endothelial-to-mesenchymal transition,EndMT)过程及具体机制。方法转染小干扰RNA(small interfering RNA,siRNA)敲低人角膜内皮细胞B4G12中SOX9的表达,使用甲萘醌构建体外B4G12细胞损伤模型,设4个分组:si-NC组(转染siRNA-阴性对照)、si-SOX9组(转染siRNA-SOX9)、si-NC+甲萘醌组(转染siRNA-阴性对照后添加外源性甲萘醌做损伤处理)、si-SOX9+甲萘醌组(转染siRNA-SOX9后添加外源性甲萘醌做损伤处理)。通过实时荧光逆转录聚合酶链反应(real-time reverse transcription polymerase chain reaction,RT-PCR)和Western blot检测各组细胞中EndMT关键因子Snail家族转录抑制因子2(snail family transcriptional repressor 2,SNAIL2)及相关信号通路关键因子表达变化,阐明SOX9调控EndMT过程的功能和机制。结果转染siRNA-SOX9敲低细胞SOX9表达后,给予甲萘醌细胞损伤处理,观察到细胞中SNAIL2的表达会随SOX9的敲低而降低,同时观察到转化生长因子β(transforming growth factor beta,TGF-β)信号通路中SNAIL2的上游关键因子Smad2/Smad3的表达也随着SOX9的敲低而降低。结论SOX9通过TGF-β信号通路调控角膜内皮损伤后EndMT过程。

胰岛素样生长因子1对人RPE细胞分泌TGF-β2、MMP-2的影响及机制研究

目的研究胰岛素样生长因子1(IGF-1)对人视网膜色素上皮细胞(ARPE-19)表达转化生长因子β2(TGF-β2)、基质金属蛋白酶2(MMP-2)的影响,并探索其作用机制。方法ARPE-19细胞分别按不同浓度IGF-1和不同浓度LY294002培养6 h、12 h、24 h、48 h,采用CCK-8法检测细胞活力,确定IGF-1、LY294002的最佳作用浓度与时间。细胞划痕法检测细胞迁移活性。ELISA法检测细胞培养上清液中TGF-β2浓度。将ARPE-19细胞分为对照组、IGF-1组(80μg·L^(-1) IGF-1)、IGF-1+LY294002组(80μg·L^(-1) IGF-1+30 mmol·L^(-1) LY294002)、LY294002组(30 mmol·L^(-1) LY294002),使用无血清DMEM/F12培养基培养,对照组不做任何处理,分别采用RT-PCR、Western blot检测细胞中TGF-β2、MMP-2、磷脂酰肌醇-3-激酶(PI3K)、蛋白激酶B(AKT)的mRNA和蛋白表达量。结果与0μg·L^(-1) IGF-1比较,80μg·L^(-1) IGF-1的细胞活力24 h变化显著(P<0.05),故确定其为IGF-1最佳作用浓度和时间。与0 mmol·L^(-1) LY294002比较,24 h的30 mmol·L^(-1) LY294002接近半数抑制浓度,故确定其为LY294002最佳作用时间和浓度。细胞划痕法检测结果显示,0μg·L^(-1) IGF-1组、40μg·L^(-1) IGF-1组、80μg·L^(-1) IGF-1组细胞迁移率整体比较及两两比较差异均有统计学意义(均为P<0.05)。ELISA检测结果显示,0μg·L^(-1) IGF-1组、40μg·L^(-1) IGF-1组、80μg·L^(-1) IGF-1组细胞上清液中TGF-β2浓度整体比较及两两比较差异均有统计学意义(均为P<0.05)。RT-PCR、Western blot检测结果显示,IGF-1、LY294002培养24 h,与对照组比较,IGF-1组细胞中TGF-β2、MMP-2、PI3K、AKT的mRNA与蛋白表达水平均升高,而LY294002组细胞中TGF-β2、MMP-2、PI3K、AKT的mRNA与蛋白表达水平均下降(均为P<0.05);与IGF-1组比较,IGF-1+LY294002组细胞中TGF-β2、MMP-2、PI3K、AKT的mRNA与蛋白表达水平均下降(均为P<0.05)。结论IGF-1能促进ARPE-19细胞增殖、迁移;IGF-1可能通过PI3K/AKT信号通路上调ARPE-19细胞中TGF-β2、MMP-2的表达,参与近视的发生与发展。

硫酸吲哚酚对心肌梗死模型小鼠心肌重构的影响

目的探讨硫酸吲哚酚(IS)对心肌梗死(myocardial infarction,MI)模型小鼠心肌重构的影响。方法C57BL/6J成年雄性小鼠50只,随机分为假手术组(Sham组)10只,硫酸吲哚酚组(Sham+IS组)10只,心肌梗死组(MI组)15只,心肌梗死+硫酸吲哚酚组(MI+IS组)15只。采用左前降支冠状动脉结扎术构建小鼠MI模型,术后第24小时,Sham+IS组和MI+IS组小鼠每天腹腔注射IS 100 mg/kg,Sham组和MI组每天腹腔注射等体积PBS,连续28 d,期间记录各组小鼠存活情况。实验第30天,心脏超声检查评估各组小鼠心脏功能,超高效液相色谱法检测各组小鼠血清中IS浓度,Masson染色评估各组小鼠梗死区心肌纤维化程度,RT-qPCR技术检测心肌组织α-sma、CollagenⅠ基因的表达水平,Western blot技术检测心肌组织TGF-β信号通路标记蛋白TGF-β、p-Smad2、p-Smad3的表达水平。结果实验第30天时,与MI组相比,MI+IS组小鼠存活率显著下降(χ^(2)=5.02,P<0.05)。与Sham组相比,Sham+IS组小鼠血清中IS浓度显著升高(t=54.87,P<0.05),与MI组相比,MI+IS组小鼠血清中IS浓度显著升高(t=38.55,P<0.05)。心脏超声检查示,Sham组和Sham+IS组的小鼠左心室舒张末期内径(LVIDd)、左心室收缩末期内径(LVIDs)、左心室射血分数(LVEF)、左心室短轴缩短率(LVFS)无显著差异(P>0.05);与MI组相比,MI+IS组小鼠LVIDd、LVIDs显著增大(t=3.96、4.31,P<0.05),LVEF、LVFS显著降低(t=5.68、4.07,P<0.05)。Masson染色示,MI+IS组与MI组比较小鼠心肌间质胶原纤维沉积明显增多。RT-qPCR技术检测显示,MI+IS组与MI组相比,小鼠心肌组织α-sma、CollagenⅠ基因的表达水平显著升高(t=8.74、4.78,P<0.05)。Western blot方法检测显示,MI+IS组与MI组相比小鼠心肌组织中TGF-β、p-Smad2、p-Smad3蛋白的表达水平均显著升高(t=4.04~5.64,P<0.05)。结论IS可加重小鼠MI后病理性心肌重构,其机制可能与TGF-β信号通路激活相关。