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.

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.

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.

Acupuncture and Moxibustion Inhibited Intestinal Epithelial-Mesenchymal Transition in Patients with Crohn's Disease Induced by TGF-β1/Smad3/Snail Pathway:A Clinical Trial Study

Objective:To explore whether acupuncture combined with moxibustion could inhibit epithelialmesenchymal transition in Crohn’s disease by affecting the transforming growth factorβ1(TGF-β1)/Smad3/Snail pathway.Methods:Sixty-three patients with Crohn’s disease were randomly divided into an observation group(31 cases)receiving moxibustion at 43℃ combined with acupuncture,and a control group(32 cases)receiving moxibustion at 37℃combined with sham acupuncture using a random number table.Patients were treated for12 weeks.Crohn’s Disease Activity Index(CDAI)was used to evaluate disease activity.Hematoxylin-eosin staining and transmission electron microscopy were utilized to observe the morphological and ultrastructural changes.Immunohistochemistry was used to detect the expression of transforming growth factorβ1(TGF-β1),TβR1,TβR2,Smad3,Snail,E-cadherin and fibronectin in intestinal mucosal tissues.Results:The decrease of the CDAI score,morphological and ultrastructural changes were more significant in observation group.The expression levels of TGF-β1,TβR2,Smad3,and Snail in the observation group were significantly lower than those before the treatment(P<0.05 or P<0.01).After treatment,the expression levels of TGF-β1,TβR2,and Snail in the observation group were significantly lower than those in the control group(all P<0.05);compared with the control group,the expression of fibronectin in the observation group was significantly decreased,and the expression of E-cadherin was significantly increased(all P<0.05).Conclusions:Moxibustion at 43℃combined with acupuncture may suppress TGF-β1/Smad3/Snail pathway-mediated epithelial-mesenchymal transition of intestinal epithelial cells in Crohn’s disease patients by inhibiting the expression levels of TGF-β1,TβR2,Smad3,and Snail.(Registration No.ChiCTR-IIR-16007751).

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.

Transcriptomic landscape regulated by the 14 types of bone morphogenetic proteins(BMPs)in lineage commitment and differentiation of mesenchymal stem cells(MSCs)

Mesenchymal stem cells(MSCs)are ubiquitously-existing multipotent progenitors that can self-renew and differentiate into multiple lineages including osteocytes,chondrocytes,adipocytes,tenocytes and myocytes.MSCs represent one of the most commonly-used adult progenitors and serve as excellent progenitor cell models for investigating lineagespecific differentiation regulated by various cellular signaling pathways,such as bone morphogenetic proteins(BMPs).As members of TGFb superfamily,BMPs play diverse and important roles in development and adult tissues.At least 14 BMPs have been identified in mammals.Different BMPs exert distinct but overlapping biological functions.Through a comprehensive analysis of 14 BMPs in MSCs,we demonstrated that BMP9 is one of the most potent BMPs in inducing osteogenic differentiation of MSCs.Nonetheless,a global mechanistic view of BMP signaling in regulating the proliferation and differentiation of MSCs remains to be fully elucidated.Here,we conducted a comprehensive transcriptomic profiling in the MSCs stimulated by 14 types of BMPs.Hierarchical clustering analysis classifies 14 BMPs into three subclusters:an osteo/chondrogenic/adipogenic cluster,a tenogenic cluster,and BMP3 cluster.We also demonstrate that six BMPs(e.g.,BMP2,BMP3,BMP4,BMP7,BMP8,and BMP9)can induce ISmads effectively,while BMP2,BMP3,BMP4,BMP7,and BMP11 up-regulate Smad-independent MAP kinase pathway.Furthermore,we show that many BMPs can upregulate the expression of the signal mediators of Wnt,Notch and PI3K/AKT/mTOR pathways.While the reported transcriptomic changes need to be further validated,our expression profiling represents the first-of-its-kind to interrogate a comprehensive transcriptomic landscape regulated by the 14 types of BMPs in MSCs.

Xueshuantong for Injection(Lyophilized,注射用血栓通)Alleviates Streptozotocin-Induced Diabetic Retinopathy in Rats

Objective To investigate the ameliorate effect and underlying mechanism of Xueshuantong for Injection(Lyophilized,注射用血栓通,XST)in streptozocin(STZ)-induced diabetic retinopathy(DR)rats.Methods Diabetes mellitus(DM)model was induced by intraperitoneal(i.p.)injection of STZ(60 mg/kg)in Sprague-Dawley rats.Diabetic rats were randomized into 3 groups(n=10)according to a random number table,including DM,XST50 and XST100 groups.XST treatment groups were daily i.p.injected with 50 or 100 mg/kg XST for 60 days,respectively.The control and DM groups were given i.p.injection with saline.Blood glucose level and body weight were recorded every week.Histological changes in the retina tissues were observed with hematoxylin-eosin staining.Apoptosis and inflammation related factors,including cleaved caspase-3,glial fifibrillary acidic protein(GFAP),tumor necrosis factor-α(TNF-α)and intercellular cell adhesion molecule-1(ICAM-1)were detected by Western blot or real-time polymerase chain reaction.Then,the levels of advanced glycation end product(AGE)and its receptor(RAGE)were investigated.Tight junctions proteins(Zonula occludens-1(ZO-1),Occludin and Claudin-5)of blood-retinal barrier were detected by Western blot.The levels of retinal fifibrosis,transforming growth factor-β1(TGF-β1)-Smad2/3 signaling pathway were evaluated at last.Results There was no signifificant difference in the body weight and blood glucose level between XST and DM groups(P>0.05).Compared with the DM group,XST treatment signifificantly increased the retinal thickness of rats(P<0.05 or P<0.01),and suppressed cleaved caspase-3 expression(P<0.01).XST increased the protein expressions of ZO-1,Occludin and Claudin-5 and decreased the mRNA expressions of matrix metalloproteinase 2(MMP-2)and MMP-9(P<0.05 or P<0.01).Moreover,XST signifificantly reduced the productions of AGE and RAGE proteins in the retina of rats(P<0.05 or P<0.01),suppressed the over-expression of TNF-α,and decreased the elevated level of ICAM-1 in retina of rats(P<0.05 or P<0.01).XST signifificantly reduced the levels ofα-smooth muscle actin(α-SMA),connective tissue growth factor(CTGF),TGF-β1 and phosphorylation of Smad2/3 protein in rats(P<0.05 or P<0.01).Conclusions XST had protective effects on DR with possible mechanisms of inhibiting the inflammation and apoptosis,up-regulating the expression of tight junction proteins,suppressing the productions of AGE and RAGE proteins,and blocking the TGF-β/Smad2/3 signaling pathway.XST treatment might play a role for the future therapeutic strategy against DR.