Electroacupuncture improves myocardial fibrosis in heart failure rats by attenuating ECM collagen deposition through modulation of TGF-β1/Smads signaling pathway

Background: To explore the effects of electroacupuncture on cardiac function and myocardial fibrosis in rat models of heart failure, and to elucidate the underlying mechanism of electroacupuncture in heart failure treatment. Methods: Healthy male Sprague-Dawley rats were allocated into three groups: Sham group, Model group, and electroacupuncture (Model + EA) group, with each group comprising 8 rats. The model underwent a procedure involving the ligation of the left anterior descending coronary artery to induce a model of heart failure. The Model + EA group was used for 7 consecutive days for electroacupuncture of bilateral Shenmen (HT7) and Tongli (HT5), once a day for 30 min each time. Left ventricular parameters in rats were assessed using a small-animal ultrasound machine to analyze changes in left ventricular end-diastolic volume, left ventricular end-systolic volume, left ventricular ejection fraction, and left ventricular fractional shortening. Serum interleukin-1β (IL-1β), cardiac troponin (cTn), and N-terminal brain natriuretic peptide precursor levels were measured using ELISA. Histopathological changes in rat myocardium were observed through HE staining, while collagen deposition in rat myocardial tissue was assessed using the Masson staining method. Picro sirius red staining, immunohistochemical staining, and RT-qPCR were utilized to distinguish between the various types of collagen deposition. The expression level of TGF-β1 and SMAD2/3/4/7 mRNA in rat myocardial tissues was determined using RT-qPCR. Additionally, western blot analysis was conducted to assess the protein expression levels of TGF-β1, SMAD3/7, and p-SMAD3 in rat myocardial tissues. Results: Compared with the Sham group, the left ventricular ejection fraction and left ventricular fractional shortening values of the Model group were significantly decreased (P < 0.01);the left ventricular end-diastolic volume and left ventricular end-systolic volume values were remarkably increased (P < 0.01);serum N-terminal brain natriuretic peptide precursor content was increased (P < 0.01);serum IL-1β and cTn levels were increased (P < 0.01);myocardial collagen volume fraction were increased (P < 0.01);and those of the expression of TGF-β1 and SMAD2/3/4 mRNA was increased (P < 0.01);the expression of SMAD7 mRNA was decreased (P < 0.01);the protein expression levels of TGF-β1, SMAD3, and p-Smad3 were increased (P < 0.01);the protein expression level of SMAD7 was decreased (P < 0.01) in the Model group. Compared to the Model group, the expression levels of the proteins TGF-β1, SMAD3, and p-Smad3 in myocardial tissue were found to be decreased (P < 0.01), and the expression level of the protein SMAD7 was found to be increased (P < 0.01) in the Model + EA group;the collagen volume fraction and deposition of type Ⅰ /Ⅲ collagen were decreased (P < 0.01) in the Model + EA group. Conclusion: Electroacupuncture alleviates myocardial fibrosis in rats with heart failure, and this effect is likely due to attributed to the modulation of the TGF-β1/Smads signaling pathway, which helps reduce collagen deposition in the extracellular matrix.

Calcitriol attenuates liver fibrosis through hepatitis C virus nonstructural protein 3-transactivated protein 1-mediated TGF β1/Smad3 and NF-κB signaling pathways

BACKGROUND Hepatic fibrosis is a serious condition,and the development of hepatic fibrosis can lead to a series of complications.However,the pathogenesis of hepatic fibrosis remains unclear,and effective therapy options are still lacking.Our group identified hepatitis C virus nonstructural protein 3-transactivated protein 1(NS3TP1) by suppressive subtractive hybridization and bioinformatics analysis,but its role in diseases including hepatic fibrosis remains undefined.Therefore,additional studies on the function of NS3TP1 in hepatic fibrosis are urgently needed to provide new targets for treatment.AIM To elucidate the mechanism of NS3TP1 in hepatic fibrosis and the regulatory effects of calcitriol on NS3TP1.METHODS Twenty-four male C57BL/6 mice were randomized and separated into three groups,comprising the normal,fibrosis,and calcitriol treatment groups,and liver fibrosis was modeled by carbon tetrachloride(CCl4).To evaluate the level of hepatic fibrosis in every group,serological and pathological examinations of the liver were conducted.TGF-β1 was administered to boost the in vitro cultivation of LX-2 cells.NS3TP1,α-smooth muscle actin(α-SMA),collagen I,and collagen Ⅲ in every group were examined using a Western blot and real-time quantitative polymerase chain reaction.The activity of the transforming growth factor beta 1(TGFβ1)/Smad3 and NF-κB signaling pathways in each group of cells transfected with pcDNA-NS3TP1 or siRNA-NS3TP1 was detected.The statistical analysis of the data was performed using the Student’s t test.RESULTS NS3TP1 promoted the activation,proliferation,and differentiation of hepatic stellate cells(HSCs)and enhanced hepatic fibrosis via the TGFβ1/Smad3 and NF-κB signaling pathways,as evidenced by the presence of α-SMA,collagen I,collagen Ⅲ,p-smad3,and p-p65 in LX-2 cells,which were upregulated after NS3TP1 overexpression and downregulated after NS3TP1 interference.The proliferation of HSCs was lowered after NS3TP1 interference and elevated after NS3TP1 overexpression,as shown by the luciferase assay.NS3TP1 inhibited the apoptosis of HSCs.Moreover,both Smad3 and p65 could bind to NS3TP1,and p65 increased the promoter activity of NS3TP1,while NS3TP1 increased the promoter activity of TGFβ1 receptor I,as indicated by coimmunoprecipitation and luciferase assay results.Both in vivo and in vitro,treatment with calcitriol dramatically reduced the expression of NS3TP1.Calcitriol therapy-controlled HSCs activation,proliferation,and differentiation and substantially suppressed CCl4-induced hepatic fibrosis in mice.Furthermore,calcitriol modulated the activities of the above signaling pathways via downregulation of NS3TP1.CONCLUSION Our results suggest that calcitriol may be employed as an adjuvant therapy for hepatic fibrosis and that NS3TP1 is a unique,prospective therapeutic target in hepatic fibrosis.

Effects of Cigu Xiaozhi Formula on miR-378a-3p Expression and Hh Signaling Pathway in TGF-β1 Induced LX2 Cells

[Objectives]To observe the effects of Cigu Xiaozhi Formula on miR-378a-3p expression and Hh signaling pathway in TGF-β1 induced and activated LX2 cells.[Methods]Cells were divided into control group,induction group,drug-containing serum group,miR-378a-3p inhibitor group,and miR inhibitor NC group.CCK-8 method was used to detect the cell viability of each group,and flow cytometry was used to detect the apoptosis rate of each group.RT-qPCR was used to detect the expression of miR-378a-3p in each group s cells,and RT-qPCR and Western blot were used to detect mRNA and protein expression of Shh,Gli1,Gli2,Col-I,andα-SMA in each group s cells.[Results]Compared with the control group,the cell viability and expression of Shh,Gli1,Gli2,Col-I,andα-SMA mRNA and protein in induction group increased(P<0.01),while the expression of miR-378a-3p decreased(P<0.01).Compared with the induction group,the cell viability and expression of Shh,Gli1,Gli2,Col-I,α-SMA mRNA andα-SMA and Gli2 protein decreased in drug-containing serum group(P<0.05),while cell apoptosis rate and miR-378a-3p expression increased(P<0.01).In miR-378a-3p inhibitor group,cell viability and the expression of Shh,Gli1,Gli2,Col-I,α-SMA mRNA and Gli1,Gli2,α-SMA protein increased(P<0.05,P<0.01),while the apoptosis rate and miR-378a-3p expression decreased(P<0.05,P<0.01).[Conclusions]Cigu Xiaozhi Formula containing serum can upregulate miR-378a-3p expression and downregulate the expression of Gli2 andα-SMA in TGF-β1 induced LX2 cells,thereby inhibiting the activation of LX2 cells and exerting the effects of anti liver fibrosis.

Berberine Attenuates Cigarette Smoke Extract-induced Airway Inflammation in Mice:Involvement of TGF-β1/Smads Signaling Pathway

Although several studies confirmed that berberine may attenuate airway inflammation in mice with chronic obstructive pulmonary disease(COPD),its underlying mechanisms were not clear until now.We aimed to establish an experiment mouse model for COPD and to investigate the effects of berberine on airway inflammation and its possible mechanism in COPD model mice induced by cigarette smoke extract(CSE).Twenty SPF C57BL/6 mice were randomly divided into PBS control group,COPD model group,low-dose berberine group and high-dose berberine group,5 mice in each group.The neutrophils and macrophages were examined by Wright's staining.The levels of inflammatory cytokines TNF-α and IL-6 in bronchoalveolar lavage fluid(BALF)were detennined by enzyme-linked immunosorbent assay.The expression levels of TGF-β1,Smad2 and Smad3 mRNA and proteins in lung tissues were respectively detected by quantitative real-time polymerase chain reaction and Western blotting.It was found that CSE increased the number of inflammation cells in BALF,elevated lung inflammation scores,and enhanced the TGF-β1/Smads signaling activity in mice.High-dose berberine restrained the alterations in the COPD mice induced by CSE.It was concluded that high-dose berberine ameliorated CSE-induced airway inflammation in COPD mice.TGF-β1/Smads signaling pathway might be involved in the mechanism.These findings suggested a therapeutic potential of high-dose berberine on the CSE-induced airway inflammation.

Cetirizine regulates scleroderma skin fibrosis in mice via the TGF-β1/Smad3 signaling pathway

Objective:To investigate the effect of cetirizine on the fibrosis of skin tissue in systemic sclerosis(SSc)mice and its mechanism of action.Methods:Thirty-two BALB/C mice were randomly divided into a blank group,a model group,a cetirizine low-dose group,and a cetirizine high-dose group,with eight in each group.The blank group was injected with normal saline on the back,and the other three groups were injected with bleomycin on the back to prepare SSc mouse models.The mice were injected once a day for 28 consecutive days,while the normal group and the model group were given saline.The dose group was administrated intragastrically at 2 mg/kg and 5 mg/kg,respectively,for 28 consecutive days.Detect the thickness of the dermis by taking the skin tissue in the back injection area of each group.Hematoxylin-eosin staining(HE)and Masson staining.Sample hydrolysis method to detect hydroxyproline(HYP)content in skin tissue.Immunohistochemical detection ofα-smooth muscle actin(α-SMA)expression in skin tissues.Enzyme-linked immunosorbent assay(ELISA)to detect serum interleukin(IL-6,IL-10)and transforming growth factor(TGF-αand TGF-β1).Quantitative real-time PCR(qRT-PCR)was used to detect the expression levels of collagen type I(COL1A1),type III collagen(COL3A1),Smad homolog 3(Smad3),and TGF-β1 mRNA.Western blot was used to detect the expression levels of COL1A1,COL3A1 and p-Smad3.Results:Compared with the blank group,the dermis thickness and HYP content of the model group increased,the skin tissue lesions and fibrosis were more severe,theα-SMA positive expression intensity in the skin tissue was higher,and the serum IL-6,IL-10,TGF-α,TGF-β1 content increased,COL1A1,COL3A1,Smad3,TGF-β1 mRNA expression levels increased in skin tissues,COL1A1,COL3A1,p-Smad3 protein expression increased,the differences were statistically significant(P<0.05).Compared with the model group,the dermal thickness and HYP content of the low and high dose cetirizine groups were reduced,the degree of skin tissue lesions and fibrosis was improved,the expression ofα-SMA in skin tissues was weakened,the levels of IL-6,IL-10,TGF-α,TGF-β1 in serum were reduced,the expression levels of COL1A1,COL3A1,Smad3 and TGF-β1 in skin tissues were reduced,and the expression levels of COL1A1,COL3A1,and p-Smad3 proteins were reduced,the decrease in the high-dose group was more significant,and the differences were statistically significant(P<0.05).Conclusion:Cetirizine can improve the degree of fibrosis of skin tissue in SSc mice and reduce the immune inflammation response.The mechanism of action is related to the TGF-β1/Smad3 signaling pathway.

Xinfuli Granule improves post-myocardial infarction ventricular remodelingand myocardial fibrosis in rats by regulating TGF-β/Smads signaling pathway

Recent clinical and experimental studies have confirmed the effects of Xinfuli Granule (XG), a compound Chinese medicine in the prevention and treatment of heart failure (HF). This study aimed to investigate the effects and the mechanisms of XG on ventricular reconstruction in rats with acute myocardial infarction (AMI).MethodsSprague-Dawley rats were subjected to left anterior descending branch ligation. The rats that survived 24 h were randomly assigned to five groups: medium-dose of XG group (MI+XGM), high-dose of XG group (MI+XGH), carvedilol group (MI+C), medium-dose of XG + carvedilol group (MI+C+XGM). Fourteen rats underwent identical surgical procedures without artery ligation, serving as sham controls. At 28 days, left ventricular weight to body weight (LVW/BW) and heart weight to body weight (HW/BW) were calculated; left ventricular ejection fraction (LVEF), left ventricular shortening fraction (LVFS), left ventricular internal diameter at systole (LVIDS) were measured by ultrasound; HE staining, Masson staining, and Sirius red staining were used to assess the myocardial pathological and physiological changes as well as myocardial fibrosis area and non-infarct zone I/III collagen ratio. Expression of Smad3 were detected and analyzed by Western blot, immunohistochemistry and immunofluorescence. P-Smad3, Smad2 and Smad7 in the TGF-β/Smads signaling pathway were also analyzed by Western blot.ResultsThe LVIDS (P < 0.01), HW/BW (P < 0.05), type I/III collagen ratio (P < 0.01) and myocardial collagen (P < 0.01) decreased significantly while the LVW/BW, LVFS (P < 0.05) increased significantly in MI+XGM group as compared with those in other groups. The expression of key signal molecules of the TGF-β/Smads signaling pathway, including Smad3, P-Smad3 and Smad2 protein were decreased, while the expression of Smad7 increased in both XG and carvedilol treatment groups as compared to those of the MI group (all P < 0.01). Immunohistochemistry and immunofluorescence further confirmed the down-regulated Smad3 expression.ConclusionXG can improve ventricular reconstruction and inhibit myocardial fibrosis in rats with AMI by regulating TGF-β/Smads signaling pathway.

MiR-146a-5p targeting SMAD4 and TRAF6 inhibits adipogenensis through TGF-β and AKT/mTORC1 signal pathways in porcine intramuscular preadipocytes

Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.

Signaling cross-talk between TGF-β/BMP and other pathways

Transforming growth factor-beta （TGF-β）/bone morphogenic protein （BMP） signaling is involved in the vast majority of cellular processes and is fundamentally important during the entire life of all metazoans. Deregulation of TGF-β/ BMP activity almost invariably leads to developmental defects and/or diseases, including cancer. The proper functioning of the TGF-β/BMP pathway depends on its constitutive and extensive communication with other signaling pathways, leading to synergistic or antagonistic effects and eventually desirable biological outcomes. The nature of such signaling cross-talk is overwhelmingly complex and highly context-dependent. Here we review the different modes of cross-talk between TGF-β/BMP and the signaling pathways of Mitogen-activated protein kinase, phosphatidylinositol-3 kinase/ Akt, Wnt, Hedgehog, Notch, and the interleukin/interferon-gamma/tumor necrosis factor-alpha cytokines, with an emphasis on the underlying molecular mechanisms.

Role of transforming growth factor-beta1-smad signal transduction pathway in patients with hepatocellular carcinoma

AIM： To explore the role of transforming growth factorbeta1 （TGF-β1）-smad signal transduction pathway in patients with hepatocellular carcinoma. METHODS： Thirty-six hepatocellular carcinoma specimens were obtained from Qidong Liver Cancer Institute and Department of Pathology of the Second Affiliated Hospital of Nanjing Medical University. All primary antibodies （polyclonal antibodies） to TGF-β1, type H Transforming growth factor-beta receptor （TβR-Ⅱ）, nuclear factor-kappaB （NF-KB）, CD34, smad4 and smad7, secondary antibodies and immunohistochemical kit were purchased from Zhongshan Biotechnology Limited Company （Beijing, China）. The expressions of TGF-β1, TβR-Ⅱ, NF- KB, smad4 and smad7 proteins in 36 specimens of hepatocellular carcinoma （HCC） and its adjacent tissue were separately detected by immunohistochemistry to observe the relationship between TGF-β1 and TβR-Ⅱ, between NF-KB and TGF-β1, between smad4 and smad7 and between TGF-β1 or TβR-Ⅱ and microvessel density （MVD）. MVD was determined by labelling the vessel endothelial cells with CD34. RESULTS： The expression of TGF-β1, smad7 and MVD was higher in HCC tissue than in adjacent HCC tissue （P〈0.01, P〈0.05,P〈0.01 respectively）. The expression of TβR-Ⅱ and smad4 was lower in HCC tissue than in its adjacent tissue （P〈0.01, P〈0.05 respectively）. The expression of TGF-β1 protein and NF-KB protein was consistent in HCC tissue. The expression of TGF-β1 and MVD was also consistent in HCC tissue. The expression of TIER- Ⅱ was negatively correlated with that of MVD in HCC tissue. CONCLUSION： The expressions of TGF-IB1, TβR- Ⅱ, NF-KB, smad4 and smad7 in HCC tissue, which are major up and down stream factors of TGF-β1-smad signal transduction pathway, are abnormal. These factors are closely related with NVD and may play an important role in HCC angiogenesis. The inhibitory action of TGF-β1 is weakened in hepatic carcinoma cells because of abnormality of TGF-β1 receptors （such as TIBR- Ⅱ） and postreceptors （such as smad4 and smad7）. NF-KB may cause activation and production of TGF-β1.

Role of TGF-βl Signaling in Heart Valve Calcification Induced by Abnormal Mechanical Stimulation in a Tissue Engineering Model

A tissue engineering model of heart valve calcification induced in a bio-reactor was established to evaluate the calcification induced by abnormal mechanical stimulation and explore the underlying molecular mechanisms.Polyethylene glycol (PEG)-modified decellularized porcine aortic leaflets seeded with human valve interstitial cells (huVICs)were mounted on a Ti-Ni alloy frame to fabricate two-leaflet and three-leaflet tissue engineered valves.The two-leaflet model valves were exposed to abnormal pulsatile flow stimulation with null (group A),low (1000mL/min,group B),medium (2000mL/min,group C),and high velocity (3000mL/min,group D)for 14 days. Morphology and calcification were assessed by yon Kossa staining,alkaline phosphatase (ALP)content,and Runx2 immunostaining.Leaflet calcification and mRNA and protein expression of transforming growth factor (TGF)-β1,bone morphogenetic protein 2 (BMP2),Smadl,and MSX2 were measured at different time points.ALP content was examined in two-leaflet valves seeded with BMP2 shRNA plasmid-infected huVICs and exposed to the same stimulation conditions.The results showed that during 14 days of flow stimulation,huVICs on the leaflet surface proliferated to generate normal monolayer coverage in groups A,B,and C.Under mechanical stimulation,huVICs showed a parallel growth pattern in the direction of the fluid flow,but huVICs exhibited disordered growth in the high-velocity flow environment,yon Kossa staining,ALP measurement,and immunohistochemical staining for Runx2 confirmed the lack of obvious calcification in group A and significant calcification in group D.Expression levels of TGF-β1,BMP2, and MSX2 mRNA and protein were increased under fluid stimulation.ALP production by BMP2 shRNA plasmid-infected huVICs on model leaflets was significantly reduced.In conclusion,abnormal mechanical stimulation in a bioreactor induced calcification in the tissue engineering valve model.The extent of calcification correlated positively with the flow velocity,as did the mRNA and protein levels of TGF-β1,BMP2,and MSX2.These findings indicate that TGF-β1/BMP2 signaling is involved in valve calcification induced bv abnormal mechanical stimulation.

Linggui Zhugan Decoction(苓桂术甘汤)Inhibits Ventricular Remodeling after Acute Myocardial Infarction in Mice by Suppressing TGF-β1 Smad Signaling Pathway

Objective:To investigate the inhibitory effect of Linggui Zhugan Decoction(LZD,苓桂术甘汤)on the ventricular remodeling(VR)after acute myocardial infarction(AMI)and related mRNA and proteins expression in transforming growth factor-beta 1(TGF-β1)/Smad signaling pathway,and explain its putative mechanism.Methods:A VR model was generated by ligation of coronary artery in mice.Two weeks after surgery,60 mice were randomly divided into the model group,the sham-operation group(distilled water),the positive control group(2.4 mg/kg simvastatin),and the low-,medium-and high-dose LZD groups(2.1,4.2,8.4 g crude drug/kg,respectively)by a random number table,10 mice in each group.Mice in each group was treated for 4 weeks.Changes of hemodynamics indices and cardiac weight index were detected by the PowerLab data acquisition and analysis recording instrument.Morphology changes of myocardial tissue were observed by hematoxylin-eosin and Masson staining.The expressions of TGF-β1,Smad2,Smad3,p-Smad2 and p-Smad3 in myocardial tissue were detected by Western blotting.The mRNA expressions of TGF-β1,Smad2 and Smad3 were detected by reverse transcription-quantitative polymerase chain reaction(RT-qPCR).The expressions of matrix metalloprotein 2(MMP2),MMP9,collagenⅠand collagen Ⅲ were observed by immunohistochemical methods.Results:VR mice showed significant dysfunction in hemodynamic indices and cardiac structure and function.Compared with the shamoperation group,myocardial tissue damage,interstitial fibrosis occurred in the model mice,left ventricular systolic pressure(LVSP),left ventricular pressure maximum contraction rate(+dp/dtmax)and left ventricular pressure maximum relaxation rate(-dp/dtmax)decreased significantly(all P<0.01),while left ventricular end-diastolic pressure(LVEDP),cardiac weight index and left ventricular weight index elevated significantly,meanwhile TGF-β1,p-Smad2,p-Smad3,Smad2,Smad3,MMP2,MMP9,collagen Ⅰ,collagen Ⅲ protein expressions in myocardial tissue and TGF-β1 Smad2 and Smad3 mRNA expressions increased significantly(all P<0.01).Compared with the model group,LZD could significantly improve the pathological changes of myocardial tissue,increase LVSP,+dp/dtmax and-dp/dtmaxf lower LVEDP,reduce the whole heart weight index and left ventricular weight index and inhibit the over-expressions of TGF-β1f p-Smad2,p-Smad3,Smad2,Smad3,MMP2,MMP9,collagenⅠand collagenⅢproteins in myocardial tissue and mRNA expressions of TGF-β1 Smad2 and Smad3(P<0.05 or P<0.01).Conclusion:LZD can significantly suppress VR induced by AMI,and its underlying mechanism may be associated with its inhibitory effect on the TGF-β1/Smad signaling pathway.

Inhibitory effects of oxyresveratrol on ERK and Smad1/2 phosphorylation and HSC activation in preventing carbon tetrachloride-induced rat liver fibrosis

Oxyresveratrol(ORes,trans-2,4,3′,5′-tetrahydroxy stilbene)naturally exists in mulberry,grapes,peanuts and other plants.It belongs to stilbene polyphenolic family and has an extra hydroxyl group at 2-position comparing with resveratrol(Res).Hence,ORes has stronger antioxidant activity than resveratrol.In present study,we employed a rat hepatic fibrosis model induced by carbon tetrachloride(CCl_(4))and administrated ORes via gavage feeding to study the protective effects and potential mechanisms of ORes against hepatic fibrosis.We demonstrated that rat liver oxidative damage induced by CCl_(4)was significantly alleviated after ORes feeding.Furthermore,the mRNA transcription levels ofα-smooth muscle actinn(˛-SMA),desmin,and two MMPs(MMP2 and MMP9)were reduced and the expression levels of transforming growth factorβ1(TGF-β1),p-small mother against decapen-taplegic protein(Smad)1/2 and p-extracellular signal-regulated kinases(ERK)1/2 in the liver tissue down-regulated dramatically.In a parallel study with Res,ORes showed more efficacious protective effect than Res against rat liver fibrosis,which is attributed to extended conjugation system due to the extra hydroxyl group at 2-position on ORes making it more electron-rich and susceptible to oxidation than Res.Therefore,dietary consumption of mulberry and other fruits containing ORes may be beneficial in the prevention of liver fibrosis.

Celastrol Protects TGF-β1-induced Endothelial-mesenchymal Transition

The endothelial-to-mesenchymal transition（End MT） in endothelial cells contributes to the development of cardiac fibrosis,ultimately leading to cardiac remodeling.In this study,the effects and molecular mechanisms of celastrol（CEL） on transforming growth factor-β1（TGF-β1）-induced End MT in human umbilical vein endothelial（HUVEC-12） cells were investigated.The presented data demonstrated that CEL significantly blocked the morphology change of HUVEC-12 cells induced by TGF-β1 without cell cytotoxicity.In accordance with these findings,CEL blocked TGF-β1-induced EndM T as evidenced by the inhibition of the mesenchymal markers,including collagen Ⅰ,Ⅲ,α-SMA,fibronectin m RNA expression,and the increase in the m RNA expression of endothelial cell marker CD31.These changes were also confirmed by double immunofluorescence staining of CD31 and vimentin.The in vitro scratch assay showed that CEL inhibited the migration capacity of the transitioned endothelial cells induced by TGF-β1.Further experiments showed that the beneficial effect of CEL on blocking the End MT in HUVEC-12 cells was associated with the suppression of the TGF-β1/Smads signalling pathway,which was also confirmed by the inhibition of its downstream transcription factor snail1,twist1,twist2,ZEB1 and ZEB2.These results indicate that CEL blocks TGF-β1-induced End MT through TGF-β1/Smads signalling pathway and suggest that it may be a feasible therapy for cardiac fibrosis diseases.

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.

Yin Yang 1(YY1) synergizes with Smad7 to inhibit TGF-β signaling in the nucleus

As a prototype of the TGF-β superfamily cytokines, TGF-β is well known for its diverse roles in embryogenesis and adult tis- sue homeostasis. TGF-β evokes cellular responses by signaling mainly through cell membrane receptors and transcription fac- tor R-Smads and Co-Smad （Smad4）, while an inhibitory Smad, Smad7, acts as a critical negative regulator of TGF-β signaling. Smad7 antagonizes TGF-β signaling by regulating the stability or activity of the receptors or blocking the DNA binding of the functional R-Smad-Smad4 complex in the nucleus. However, the function of Smad7 in the nucleus is not fully understood. Yin Yang 1 （YY1） is a ubiquitously expressed transcription factor with multiple functions. It has been reported that YY1 can inhib- it Smad-dependent transcriptional responses and TGF-β/BMP-induced cell differentiation independently of its DNA binding ability. In this study, we found that Smad7 interacts with YY1 and the interaction is attenuated by TGF-β signaling. Reporter assays and target gene expression analyses revealed that Smad7 and YY1 act in concert to inhibit TGF-β-induced transcription in the nucleus. Furthermore, Smad7 could enhance the interaction of YY1 with the histone deacetylase HDAC1. Consistently, YY 1 and HDAC 1 augmented the transcription repression activity of Smad7 in Gal4-1uciferase reporter analysis. Therefore, our findings define a novel mechanism of Smad7 and YY1 to antagonize TGF-β signaling.

Jujuboside A ameliorates tubulointerstitial fibrosis in diabetic mice through down-regulating the YY1/TGF-β1 signaling pathway

Diabetic nephropathy(DN)is one of the most common complications of diabetes mellitus,which is characterized in renal tubulointerstitial fibrosis(TIF).The current study was designed to investigate the protective effect of Jujuboside A(Ju A)on TIF in type 2 diabetes(T2DM)mice,and explore its underlying anti-fibrosis mechanism.A mouse T2DM model was established using high fat diet(HFD)feeding combined with intraperitoneal injection of streptozotocin(STZ).Then,diabetic mice were treated with Ju A(10,20 and 40 mg·kg^(−1)·d^(−1),i.g.)for 12 weeks.Results showed that administration of Ju A not only down-regulated fasting blood glucose(FBG)levels,but also improved hyperlipidemia and renal function in diabetic mice.Moreover,the reduced ECM accumulation was observed in the renal cortex of Ju A treated diabetic mice,while the TIF progression was also attenuated by Ju A through blocking the epithelial-to-mesenchymal transition(EMT)of renal tubular epithelial cells(RTECs).Further mechanism studies showed that Ju A treatment effectively down-regulated the protein expression and subsequent nuclear translocation of Yin Yang 1(YY1)in the renal cortex of diabetic mice,and reduced the levels of transforming growth factor-β1(TGF-β1)in the serum and renal cortex of Ju A treated mice.According to in vitro studies,the up-regulated YY1/TGF-β1 signaling pathway was restored by Ju A in high glucose(HG)cultured HK-2 cells.Taken together,these findings demonstrated that Ju A can ameliorate the TIF of DN through down-regulating the YY1/TGF-β1 signaling pathway.

Taxus chinensis ameliorates diabetic nephropathy through down-regulating TGF-β1/Smad pathway

Diabetic nephropathy(DN) is one of the common microvascular complications of diabetes mellitus. Renal fibrosis is closely related to the deterioration of renal function. The present study aimed to investigate protective effect of Taxus chinensis on high-fat diet/streptozotocin-induced DN in rats and explore the underlying mechanism of action. The rat DN model was established via feeding high fat diet for 4 weeks and subsequently injecting streptozotocin(30 mg·kg^(-1) body weight) intraperitoneally. The rats with blood glucose levels higher than 16.8 mmol·L^(-1) were selected for experiments. The DN rats were treated with Taxus chinensis orally(0.32, 0.64, and 1.28 g·kg^(-1)) once a day for 8 weeks. Taxus chinensis significantly improved the renal damage, which was indicated by the decreases in 24-h urinary albumin excretion rate, blood serum creatinine, and blood urea nitrogen. Histopathological examination confirmed the protective effect of Taxus chinensis. The thickness of glomerular basement membrane was reduced, and proliferation of mesangial cells and podocytes cells and increase in mesangial matrix were attenuated. Further experiments showed that Taxus chinensis treatment down-regulated the expression of TGF-β1 and α-SMA, inhibited phosphorylation of Smad2 and Smad3. These results demonstrated that Taxus chinensis alleviated renal injuries in DN rats, which may be associated with suppressing TGF-β1/Smad signaling pathway.

Huoxin Pill(活心丸)Attenuates Cardiac Fibrosis by Suppressing TGF-β1/Smad2/3 Pathway in Isoproterenol-Induced Heart Failure Rats

Objective:To evaluate the effects of Huoxin Pill(活心丸,HXP)on cardiac fibrosis and heart failure(HF)in isoproterenol(ISO)-induced HF rats.Methods:Thirty Wistar rats were randomly divided into 5 groups including control,HF,isosorbide mononitrate(ISMN),HXP low(HXP-L),and HXP high(HXP-H)groups(n=6 for each group)according to the complete randomization method.Rats were pretreated with ISMN(5 mg/kg daily),low concentration of HXP(10 mg/kg daily)or high concentration of HXP(30 mg/kg daily)or equal volume of saline by intragastric administration for 1 week,followed by intraperitoneal injection of ISO(10 mg/kg,14 days),and continually intragastric administrated with above medicines or saline for additional 6 weeks.The effects of HXP treatment on the cardiac function,heart weight index(HWI),pathological changes,and collagen content were further assessed.Moreover,the role of HXP on activation of transforming growth factor-β1(TGF-β1)/Smads pathway was further explored using immunohistochemistry(IHC)and Westernblot assay.Results:HXP treatment significantly alleviated the decrease of ejection fraction(EF)and fractional shortening(FS),while decreased the elevation of left ventricular end-systolic volume(LVESV)in ISO-induced HF rats(P<0.05).Moreover,HXP treatment obviously attenuated the increase of HWI and serum level of creatine kinase MB(CK-MB,P<0.05),as well as pathological changes in ISO-induced HF rats.Further determination indicated that HXP treatment alleviated the elevation of collagenⅠand collagenⅢprotein expression in cardiac tissues of ISO-induced HF rats.Furthermore,HXP treatment significantly down-regulated the increase of TGF-β1 and p-Smad2/3 protein expression in cardiac tissues of HF rats(P<0.05),while did not affect the expression of total Smad2/3.Conclusions:HXP attenuated heart failure and cardiac fibrosis in ISO-induced HF rats by suppression of TGF-β1/Smad2/3 pathway.

Qingxuan Jiangya Decoction(清眩降压汤) Prevents Blood Pressure Elevation and Ameliorates Vascular Structural Remodeling via Modulating TGF-β 1/Smad Pathway in Spontaneously Hypertensive Rats

Objective:To elevate the effects of Qingxuan Jiangya Decoction(清眩降压汤,QXJYD)on hypertension and vascular structural remodeling(VSR)in spontaneously hypertensive rats(SHRs),and investigate the underlying mechanisms.Methods:SHRs(n=8)were given intra-gastric administration with 60 mg/kg of QXJYD or saline,daily for 8 weeks,while rats in SHR-control(n=8)and WKY(n=8)groups were received equal volumes of saline solution.Systolic blood pressures(SBP),diastolic blood pressures(DBP)and mean blood pressures(MBP)were measured once a week.The levels of angiotensinⅡ(AngⅡ),endothelin 1(ET-1)and plasma renin activity(PRA)were tested by enzyme-linked immunosorbent assay(ELISA)and radioimmunoassay,respectively.The effect of QXJYD on VSR was determined by examining the media thickness and the ex vivo contractility of thoracic aortic.The proliferation and fibrosis of vascular smooth muscle cells(VSMCs)were examined via immunohistochemical(IHC)staining for proliferating cell nuclear antigen(PCNA),collagen Ⅰ and collagen Ⅲ,respectively.The mRNA and protein expressions of transforming growth factor β1(TGF-β1),Smad3 and phosphorylation of Smad3 in thoracic aorta tissues were determined by real-time polymerase chain reaction(PCR)and Western blot assay,respectively.Results:QXJYD treatment led to a significant decrease of the elevation of blood pressure in SHRs and reduced the levels of AngⅡ,ET-1 and PRA in the serum(P<0.05).In addition,QXJYD treatment remarkably ameliorated VSR and vascular function in SHRs.Moreover,QXJYD inhibited VSMC proliferation and fibrosis by suppressing the expression of PCNA,collagen Ⅰ and collagen Ⅲ in thoracic aortic.Furthermore,QXJYD inhibited the expression of TGF-β1,Smad3 and the phosphorylation of Smad3,respectively(P<0.05).Conclusion:QXJYD reversed VSR by inhibiting VSMC proliferation and collagen deposition via regulation of TGF-β1/Smad signaling pathway,which may,in part,illuminate its anti-hypertensive activities.

Effects of transforming growth factor-β_1 and signal protein Smad3 on rat cardiomyocyte hypertrophy

Background SMAD proteins have recently been identified as the first family of putative transforming growth factor-β_1(TGF-β_1) signal transducers. This study was to investigate the effects of TGF-β_1 and signal protein Smad3 on rat cardiac hypertrophy.Methods The incorporation of [3H]-leucine was measured to determine the hypertrophy of cardiomyocyte incubated with different doses of TGF-β_1 in cultured neonatal cardiomyocytes. The model of rat cardiac hypertrophy was produced with constriction of the abdominal aorta. At different times after the operation, rats were killed, and their left ventricular mass index (LVMI) determined. The mRNA expression of TGF-β_1 and Smad3 of cultured cells and hypertrophic left ventricles were assessed by RT-PCR. The protein expression of Smad3 was assessed by Western blot.Results In cultured neonatal cardiomyocytes, TGF-β_1 significantly promoted incorporation of [3H]-leucine. With the concentration of 3 pg/L, it increased the expression of Smad3 in mRNA and protein levels after 15 minutes, and continued for up to 8 hours of cultured cardiomyocytes. The LVMI and the expression of TGF-β_1 (mRNA) and Smad3 (mRNA and protein) of hypertrophic left ventricle were increased by day 3 after the operation and continued to the 4th week. The peak expression of these was in the second week after operation.Conclusion TGF-β_1 has positive effects on rat cardiomyocyte hypertrophy. Signal protein Smad3 could be related to the pathologic progression of rat cardiac hypertrophy.