Experimental study of TGF-β1/Smads pathway inhibition of macrophage polarization based on miR145-5P negative feedback regulation

imbalance of synovial macrophages in patients with rheumatoid arthritis(RA).Methods:Human mononuclear cells(THP‑1)at logarithmic growth stage were induced into M1‑type macrophages,and RA synovial fibroblasts M1‑type macrophages were co‑cultured into synovial macrophages.Synovial macrophages were divided into four groups:RA group(blank group),TGF‑β1 group(model group)and miR145‑5P overexpression group(TGF‑β1+miR145‑5P mimics group)and miR145‑5P overexpression negative control group(TGF‑β1+miR145‑5P‑mimics‑NC group).The blank group did not receive any treatment,and the other three groups were induced by TGF‑β1 in the medium for 48 h.Transfection miR145‑5p mimic and miR145‑5P‑mimics‑NC were added to co‑culture medium,and IL‑6,IL‑6 and IL‑6 of synovial macrophages were detected by ELISA.CD163 expression.Rt‑qpcr was used to detect miR145‑5p mRNA,TGF‑β1mRNA,Smad3mRNA,Smad7mRNA expression level.The expression of TGF‑β1/Smads pathway related proteins was detected by Western Blotting.Results:Compared with blank group,IL‑6 level was up‑regulated(P<0.01),and CD163 level was down‑regulated in model group(P<0.05),suggesting that TGF‑β1 could induce intensified immune inflammatory response.Compared with the negative miR145‑5P overexpression control group and model group,The expression of miR145‑5P overexpression group molecule CD163 was significantly increased by ELISA(P<0.01),and the expression of inflammatory factor IL‑6 was decreased(P<0.05).PCR showed that miR145‑5P mRNA expression level was significantly increased in miR145‑5P overexpression group,Smad3 mRNA and TGF‑β1 mRNA were significantly decreased,and Smad7 mRNA was significantly increased(P<0.01).WB method showed that the anti‑inflammatory protein Smad7 was significantly increased,while TGF‑β1 and Smad3 were significantly decreased(P<0.01).Transwell chamber results confirmed that miR145‑5P overexpression group significantly reduced macrophage invasion(P<0.01).Correlation analysis showed that miR145‑5P was negatively correlated with Smad3 and positively correlated with Smad7(P<0.01).Conclusion:miR145‑5P may inhibit macrophage polarization in RA patients by targeting Smad3 protein,negatively regulating TGF‑β1/Smads pathway,and alleviating immune inflammation.

Correlation analysis of changes in miR145‑5p/Smads pathway and macrophage polarization in adjuvant arthritis rats

Objective:To explore the relationship between the changes of miR145‑5p/Smads pathway and macrophage polarization in adjuvant arthritis rats.Methods:Twelve rats were divided into normal group and model group induced by freund's complete adjuvant(0.1 mL/mouse)by random number table method,with 6 rats in each group.The expression of inflammatory polarization markers IL‑8 and CD206 in synovial tissue was detected by enzyme‑linked immunosorbent assay on the 12th day after the formation of arthritis in rats.Western blotting was used to detect the expression of TGF‑β1/Smads pathway factors in synovial tissues.The expression of miR145‑5P,Smads3 and Smads7 in synovial tissue was detected by RT‑qPCR.Results:Compared with normal group,the expression levels of IL‑8,TGF‑β1 and Smad3 in model group were significantly increased(P<0.05);The expression levels of CD206,Smad7 and miR145‑5P were significantly decreased(P<0.01).The correlation results showed that IL‑8 was positively correlated with Smad3(P<0.01),IL‑8 was negatively correlated with Smad7(P<0.05),CD206 was negatively correlated with Smad3(P<0.01)and positively correlated with Smad7(P<0.05).miR145‑5p was negatively correlated with Smad3(P<0.01)and positively correlated with Smad7(P<0.01).Conclusion:miR145‑5p may inhibit the overactivation of TGF‑β1/Smads pathway,regulate macrophage polarization,and inhibit the development of adjuvant arthritis by inhibiting Smad3 expression.

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.

Losartan prevents aortic dissection via downregulating TGF-β/SMADs pathway in Sprague Dawley rats

Background Aortic dissection(AD)is a lethal medical emergency,which lacks specific biomarkers and effective pharmaceutical therapies.Increasing evidences have shown beneficial effect of angiotensin receptor blocker(ARB)drugs on downregulating transforming growth factor-β(TGF-β)pathway in Marfanoid AD.However,for non-Marfanoid AD,the effectiveness of ARB drugs,as well as the possible mechanisms,remains unclear.Methods Sprague Dawley(SD)rats were fed by gavage(i.g.)with either 150 mg/(kg·d)Hydroxyethyl diamine(AEEA)or isovolumic saline(normal saline group).AEEA-induced SD rats were further randomly divided into three groups,including the AEEA+Losartan group[AEEA induction+20 mg/(kg·d)i.g.Losartan],the AEEA+Amlodipine group[AEEA induction+6.5 mg/(kg·d)i.g.Amlodipine]and the AEEA+normal saline group(AEEA induction+isovolumic saline i.g.)group.Thus there were 4 groups with 12 mice in each.Tail blood pressure,aortic diameter and the number of aortic dissected lesions were measured in the above 4 groups 4 weeks thereafter.Western-blot was used to detect the expression of components of TGF-β/SMADs pathway,such as TGF-β1,drosophila mothers against decapentaplegic protein 2(Smad2),Smad3,Smad4,protein kinase B(AKT)and phosphorylated AKT(p-AKT).Results No significant difference of blood pressure was seen between the AEEA+Losartan group and the AEEA+Amlodipine group(P=0.81).Ultrasound data indicated a significant reduction in aortic dilation of ascending aorta,aortic arch and descending aorta in Losartan intervention group relative to the Amlodipine intervention group(P<0.001).Hematoxylin-eosin(HE)staining of aortic tissue demonstrated that under the setting of AEEA induction,AEEA+Losartan group had a lower incidence of aortic dissection than the AEEA+normal saline group and the AEEA+Amlodipine group(all P<0.01).Losartan significantly reduced the expression of TGF-β1,Smad2,Smad3,Smad4 in aortic tissues of AEEA-induced rats(all P<0.05).Conclusions Independent of BP reduction,Losartan,as an ARB drug,can prevent aortic dissection by inhibiting TGF-β/SMADs signaling pathway.

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

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

Effect of the Protease Inhibitor MG132 on the Transforming Growth Factor-β/Smad Signaling Pathway in HSC-T6 Cells

Summary： The activation of hepatic stellate cells （HSCs） and their transformation to myofibroblasts are the key steps in the pathological progress of liver fibrosis. The transforming growth factor-J3 （TGFβ）/Smad pathway is involved in the proliferation and collagen synthesis of HSCs. This study aimed to examine the effect of the protease inhibitor MG132 on the signaling pathway of TGFβ/Smad in HSC-T6 cells and seek a novel therapeutic approach for liver fibrosis. The HSC-T6 cells were treated with MG132 at different concentrations （0-10 maol/L）. Cell proliferation was detected by MTT method. The mRNA and protein expression levels of TGFI31, Smad3 and Smad7 were determined in HSC-T6 cells by real-time PCR and Western blotting, respectively, after treatment with MG132 at different con- centrations （1, 2, 3 μtmol/L） or RPMI1640 alone （serving as control）. The results showed that MG132 could inhibit the proliferation of HSC-T6 cells in a dose-dependent manner, and the IC50 of MG132 was 6.84 μmol/L. After treatment with MG132 at 1, 2 or 3 nol/L for 24 h, the mRNA expression levels of TGF-β1 and Smad3 were significantly decreased （P〈0.05）, but the Smad7 mRNA expression had no significant change （P〉0.05）. There was also a significant decrease in the protein expression level of TGF-β1 and Smad3 （P〈0.05）. However, the expression of Smad7 protein was substantially increased when compared with the control group （P〈0.05）. It was concluded that the inhibition of TGFi/Smad pathway in HSC-T6 cells by MG132 can reduce the production of profibrosis factors （TGFI31, Smad3） and promote the expression of anti-fibrosis factor （Smad7）, suggesting that MG132 may become a po- tential therapeutic alternative for liver fibrosis.

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.

Salvianolic acid A reduces endothelial-mesenchymal transition of HPAECs

OBJECTIVE Salvianolic acid A(SAA),a polyphenols acid,is a bioactive ingredient from a traditional Chinese medicine named Danshen(Salvia Miltiorrhiza Bunge).According to previous studies,it was shown to possess various effects such as anti-oxidative stress,anti-diabetic complications and anti-pulmonary hypertension.This study is aimed to investigate the effect of SAA on pulmonary arterial endothelial-mesenchymal transition(endoMT)induced by hypoxia and the underlying mechanisms.METHODS Primary cultured human pulmonary arterial endothelial cells(HPAECs)were exposed to 1%O2 for 48 h with or without SAA treatment.RESULTS SAA treatment improved the morphology of HPAECs and inhibited the cytoskeleton remodeling and reduced migration distances.It was observed that the produc⁃tion of ROS in cells was significantly reduced by the treatment of SAA.Meanwhile,SAA alleviated the loss of CD31 and slightly inhibited the expression ofα-SMA.The mechanisms study shows that SAA treatment increased the phosphoryla⁃tion levels of Smad1/5,but inhibited that of Smad2/3.Furthermore,SAA attenuated the phosphorylation levels of ERK and Cofilin,which were enhanced by hypoxia.CONCLUSION SAA treatment can protect HPAECs from endoMT induced by hypoxia,which may perform via the downstream effectors of BMPRs or TGFβR including Smads,ERK and ROCK/cofilin pathways.

IGFBPrP1 induces liver fibrosis by inducing hepatic stellate cell activation and hepatocyte apoptosis via Smad2/3 signaling

AIM: To investigate the role and mechanism of insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) in the development of liver fibrosis.

Activin A prevents neuron-like PC12 cell apoptosis after oxygen-glucose deprivation

In this study, PC12 cells were induced to differentiate into neuron-like cells using nerve growth factor, and were subjected to oxygen-glucose deprivation. Cells were treated with 0, 10, 20, 30, 50, 100 ng/mL exogenous Activin A. The 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl tetrazolium bromide assay and Hoechst 33324 staining showed that the survival percentage of PC12 cells significantly decreased and the rate of apoptosis significantly increased after oxygen-glucose deprivation. Exogenous Activin A significantly increased the survival percentage of PC12 cells in a dose-dependent manner. Reverse transcription-PCR results revealed a significant increase in Activin receptor IIA, Smad3 and Smad4 mRNA levels, which are key sites in the Activin A/Smads signaling pathway, in neuron-like cells subjected to oxygen-glucose deprivation, while mRNA expression of the apoptosis-regulation gene caspase-3 decreased. Our experimental findings indicate that exogenous Activin A plays an anti-apoptotic role and protects neurons by means of activating the Activin A/Smads signaling pathway.

Gardenia jasminoides attenuates hepatocellular injury and fibrosis in bile duct-ligated rats and human hepatic stellate cells

AIM:To investigate the anti-hepatofibrotic effects of Gardenia jasminoides in liver fibrosis.METHODS:Male Sprague-Dawley rats underwent common bile duct ligation(BDL) for 14 d and were treated with Gardenia jasminoides by gavage.The ef-fects of Gardenia jasminoides on liver fibrosis and the detailed molecular mechanisms were also assessed in human hepatic stellate cells(LX-2) in vitro.RESULTS:Treatment with Gardenia jasminoides decreased serum alanine aminotransferase(BDL vs BDL + 100 mg/kg Gardenia jasminoides,146.6 ± 15 U/L vs 77 ± 6.5 U/L,P = 0.0007) and aspartate aminotransferase(BDL vs BDL + 100 mg/kg Gardenia jasminoides,188 ± 35.2 U/L vs 128 ± 19 U/L,P = 0.005) as well as hydroxyproline(BDL vs BDL + 100 mg/kg Gardenia jasminoides,438 ± 40.2 μg/g vs 228 ± 10.3 μg/g liver tissue,P = 0.004) after BDL.Furthermore,Gardenia jasminoides significantly reduced liver mRNA and/or protein expression of transforming growth factor β1(TGF-β1),collagen type?Ⅰ?(Col?Ⅰ) and α-smooth muscle actin(α-SMA).Gardenia jasminoides significantly suppressed the upregulation of TGF-β1,Col?Ⅰand α-SMA in LX-2 exposed to recombinant TGF-β1.Moreover,Gardenia jasminoides inhibited TGF-β1-induced Smad2 phosphorylation in LX-2 cells.CONCLUSION:Gardenia jasminoides exerts antifibrotic effects in the liver fibrosis and may represent a novel antifibrotic agent.

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.

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.

Serum Iron Overload Activates the SMAD Pathway and Hepcidin Expression of Hepatocytes via SMURF1

Background and Aims:Liver iron overload can induce hepatic expression of bone morphogenic protein(BMP)6 and activate the BMP/SMAD pathway.However,serum iron overload can also activate SMAD but does not induce BMP6 expression.Therefore,the mechanisms through which serum iron overload activates the BMP/SMAD pathway remain unclear.This study aimed to clarify the role of SMURF1 in serum iron overload and the BMP/SMAD pathway.Methods:A cell model of serum iron overload was established by treating hepatocytes with 2 mg/mL of holo-transferrin(Holo-Tf).A serum iron overload mouse model and a liver iron overload mouse model were established by intraperitoneally injecting 10 mg of Holo-Tf into C57BL/6 mice and administering a high-iron diet for 1 week followed by a low-iron diet for 2 days.Western blotting and real-time PCR were performed to evaluate the activation of the BMP/SMAD pathway and the expression of hepcidin.Results:Holo-Tf augmented the sensitivity and responsiveness of hepatocytes to BMP6.The E3 ubiquitin-protein ligase SMURF1 mediated Holo-Tf-induced SMAD1/5 activation and hepcidin expression;specifically,SMURF1 expression dramatically decreased when the serum iron concentration was increased.Additionally,the expression of SMURF1 substrates,which are important molecules involved in the transduction of BMP/SMAD signaling,was significantly upregulated.Furthermore,in vivo analyses confirmed that SMURF1 specifically regulated the BMP/SMAD pathway during serum iron overload.Conclusions:SMURF1 can specifically regulate the BMP/SMAD pathway by augmenting the responsiveness of hepatocytes to BMPs during serum iron overload.

Pharmacological mechanisms of Yishen Xingyang capsule in the treatment of oligoasthenospermia in rats

Objective:To investigate the therapeutic effects and pharmacological mechanisms of Yishen Xingyang capsule(YXC)in oligoasthenospermia(OA)rats.Methods:Forty-eight male SpragueeDawley rats were randomly divided into eight groups of six rats each:normal control(NC);model control(MC);three different positive drug(PD);and low-,medium-,and high-dose YXC groups.A rat model of OA was established by administering glucosides of Tripterygium wilfordii Hook.F(GTW).After YXC administration,penile erectile function was observed.The epididymis,blood,and testes of the rats were harvested for analysis of sperm quality,sex hormone levels,mitochondrial membrane potential,and the transforming growth factor(TGF)-b1/Smad signaling pathway.Results:Compared with that in the MC group,penile erectile function in the YXC groups and three PD groups increased(all P<.01).Moreover,sperm quality in the YXC groups and three PD groups improved(all P<.001).The levels of testosterone,follicle stimulating hormone,and luteinizing hormone in the three PD and YXC groups increased(all P<.05).The mitochondrial membrane potential in the three PD and YXC groups significantly improved(all P<.001).Furthermore,the YXC and three PD groups showed decreased TGF-b1 expression(all P<.05)compared with the MC group.The high-dose YXC group and three PD groups improved Smad2 and Smad4 expression(all P<.05).Conclusion:YXC improved penile erectile function and sperm quality in OA rats,and the underlying mechanism included increase in sex hormones,inhibition of sperm apoptosis,and regulation of the TGFb1/Smad signaling pathway.Meanwhile,this study provides a new effective drug option for the treatment of OA,which is beneficial to male reproductive health and social harmony.

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.

Effect of ursodeoxycholic acid on TGF betal/Smad signaling pathway in rat hepatic stellate cells

Background Hepatic fibrosis is the key stage of the pathological progress from hepatic injury to cirrhosis. Ursodeoxycholic acid （UDCA） has been known as having significant clinical therapeutic effects on chronic liver diseases. Our research aimed to study the effect of UDCA on the signaling pathway of transforming growth factor beta1 （TGFβ1）/Smad and discuss its possible molecular mechanisms of inhibiting hepatic fibrosis. Methods Rat hepatic stellate cells were cultured in vitro and randomly assigned to 4 groups. Group A was control group with only DMEM culture medium applied, and groups B, C, D were experimental groups, with different doses of UDCA （1.0 mmol/L, 0.5 mmol/L and 0.25 mmol/L respectively） added into their DMEM culture medium for further culture of 24 hours and 48 hours. The protein expressions of TGFβ1, TGF type 1 receptor, Smad3, Smad4 and Smad7 were measured by Western blotting, as well as the expressions of TGFβ1, Smad3, Smad7 and cAMP response element （CREB） binding protein （CBP） mRNA by real-time PCR. SPSS 11.5 statistical package was adopted for data analyses. Results Compared with control group, the mRNA expressions of TGFβ1 in the high and middle UDCA dose groups for 24 hours and 48 hours significantly decreased （P 〈0.05）, the protein expressions of TGFβ1 in the two above groups for 48 hours and in the high dose group for 24 hours significantly decreased （P 〈0.05）. The protein and mRNA expressions of Smad3 in each UDCA dose group for 24 hours and 48 hours significantly decreased, with significant difference among different UDCA dose groups and between that of 24 hours and 48 hours observed （P 〈0.05）. The protein and mRNA expressions of Smad7 in the high and middle UDCA dose groups for 24 hours and 48 hours significantly increased. The CBP mRNA expression in each UDCA dose group for 24 hours and 48 hours significantly decreased （P 〈0.05）, with significant difference among different UDCA dose groups observed （P 〈0.05）. Conclusion UDCA could curb the development of hepatic fibrosis through affecting the signaling pathway of TGFβ1/Smad by inhibiting the expressions of TGFβ1, Smad3 and CBP and increasing the expression of Smad7.

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.

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.