Dihydroergotamine ameliorates liver fibrosis by targeting transforming growth factor β type Ⅱ receptor

BACKGROUND The transforming growth factor β(TGFβ) signaling pathway plays a crucial role in the development of liver fibrosis by activating TGFβ type Ⅱ receptor(TGFβR2), followed by the recruitment of TGFβR1 finally triggering downstream signaling pathway.AIM To find drugs targeting TGFβR2 that inhibit TGFβR1/TGFβR2 complex formation, theoretically inhibit TGFβ signaling pathway, and thereby ameliorate liver fibrosis.METHODS Food and Drug Administration-approved drugs were screened for binding affinity with TGFβR2 by virtual molecular docking. We identified 6 candidates and further explored their potential by Cell Counting Kit-8(CCK-8) cell cytotoxic experiment to validate toxicity and titrated the best cellular working concentrations. Next, we further demonstrated the detailed molecular working mechanisms using mutagenesis analysis. Finally, we used a mouse model to investigate its potential anti-liver fibrosis effect.RESULTS We identified 6 drug candidates. Among these 6 drugs, dihydroergotamine(DHE) shows great ability in reducing fibrotic gene expressions such as collagen, p-SMAD3, and α-SMA in TGFβ induced cellular model of liver fibrosis in LX-2 cells. Furthermore, we demonstrated that DHE binds to TGFβR2. Moreover, mutation of Leu27, Phe30, Thr51, Ser52, Ile53, and Glu55 of TGFβR2 disrupted the binding of TGFβR2 with DHE. In addition, DHE significantly improved liver fibrosis, as evidenced by Masson’s trichrome staining of liver sections. This is further supported by the width and the velocity of the portal vein, and serum markers of liver function. In line with those observations, DHE also decreased macrophages infiltration and extracellular matrix deposition in the liver.CONCLUSION DHE alleviates liver fibrosis by binding to TGFβR2 thereby suppressing TGFβ signaling pathway. We show here that as far as drug repurposing, DHE has great potential to treat liver fibrosis.

Interference of Y-27632 on the signal transduction of transforming growth factor beta type 1 in ocular Tenon capsule fibroblasts

AIM: To investigate the interfering effect of Y-27632, a ROCK-I selective inhibitor, on the signal transduction pathway of transforming growth factor-beta 1 (TGF-beta 1) in ocular Tenon capsule fibroblasts (OTFS) in vitro. METHODS: After OTFS from passages 4 to 6 47 vitro were induced by TGF-beta 1 and then treated by Y-27632, the changes of the OTFS cell cycles were analyzed via flow cytometry, and the proteins expression of the alpha -smooth muscular actin (alpha -SMA), connective tissue growth factor (CTGF), collagen I were calculated by Western blot. After OTFS treated by the different concentrations of Y-27632, the expression levels of the alpha -SMA, CTGF and collagen I mRNA were assayed by RT-PCR. RESULTS: Y-27632 had no markedly effect on the OTFS cell cycles. After treated by TGF-beta 1, OTFS in G1 period significantly increased. The cell cycles distribution by both TGF-beta 1 and Y-27632 had no remarkable difference from that in control group. Y-27632 significantly inhibited the proteins expressions of both alpha -SMA and CTGF, while to some extent inhibited that of collagen I. TGF-beta 1 significantly promoted the proteins expressions of alpha -SMA, CTGF and collagen I. After OTFS treated by both TGF-beta 1 and Y-27632, of alpha -SMA, the protein expression was similar with that in control group (P=0.066>0.05), but the protein expression of CTGF or collagen I, respectively, was significantly different from that in control group (P=0.000<0.01). The differences of expressions of the alpha -SMA, CTGF and collagen I mRNA in 30, 150, 750 mu mol/L Y-27632 group were statistically significant, compared with those in control group, respectively (alpha -SMA, P=0.002, 0.000, 0.000; CTGF, P=0.014, 0.002, 0.001; collagen I,P=0.003, 0.002, 0.000). CONCLUSION: Blocking the Rho/ROCK signaling pathway by using of Y-27632 could inhibit the cellular proliferation and the expression of both CTGF and alpha -SMA whatever OTFS induced by TGF-beta 1 or not. Y-27632 suppressed the expression of collagen I mRNA without induction.

Expression patterns of transforming growth factor-beta and its receptors in gastric mucosa of patients with refractory gastric ulcer

AIM: Transforming growth factor-β (TGF-β) plays a regulatory role in tissue repair. In a previous study, we found that TGF-β and its receptors were expressed in gastric mucosa of patients with well-healed gastric ulcers, as demonstrated by immunohistochemistry. To further characterize the role of TGF-β and its receptors in repairing gastric ulcers, we investigated the expression patterns of TGF-β and its receptors in gastric mucosa by in situ hybridization and reverse transcriptase-polymerase chain reaction (RT-PCR).METHODS: Seventy-four patients with endoscopically proven gastric ulcers were eligible for participation in this study. All patients had routine biopsies on initial endoscopy and were then treated for 12 wk with an H2 blocker. Repeat endoscopy was then performed. There were 8 patients with poorly healed ulcers, and biopsies were taken from the margin of the residual ulcers. These tissue samples, along with biopsy of gastric mucosa near the original ulcers from 8 randomly selected patients with well-healed ulcers were examined for TGF-β and TGF-β receptor Ⅱ mRNA by RT-PCR and in situ hybridization, as well as immunohistochemistry.RESULTS: TGF-β and TGF-β receptor Ⅱ were strongly expressed in tissues from patients with well-healed ulcers.Four of the 8 patients with poor healing had low or absent expression of TGF-β or TGF-β receptor Ⅱ mRNA. All cases positive by RT-PCR assay were confirmed by in situ hybridization as well as immunohistochemistry.CONCLUSION: It is suggested that TGF-β and its receptors are important for gastric ulcer healing. These results may have implications for further investigation of the healing process and in predicting response to therapy.

Detection of Frameshift Mutations of the Transforming Growth Factor p ReceptorⅡin Gastric Cancers with Microsatellite Instability

OBJECTIVE To study the relationship among microsatellite instability (MSI), frameshift mutations (FM) of the transforming growth factor p receptorⅡ(TGFpRⅡ), methylation state of the hMLH1 promoter and hMLH1 protein expression level in gastric cancers, and to explore their relationship to gastric carcinogenesis. METHODS DMA was isolated from 101 gastric specimens and 5 microsatellite loci were detected. PCR, electrophoresis on denatured polyacrylamide gels and silver staining were performed to detect the MSI. The FMs of TGFβRⅡwere also screened with the same method. HMLH1 methylation was analyzed by methylation specific PCR (MSP) and sequencing. HMLH1 protein expression was detected using immunohistochemistry. RESULTS The incidence of MSIs was 53.7% and 0% in the cancers and normal tissues, respectively, with the frequency of MSIs being significantly higher in the gastric cancers compared to the normal gastric tissues (P<0.05). The frequency of hMLH1 methylation was 41.5%(17/41) in the gastric cancers and 0%(0/60) in the normal group. Decreased hMLH1 expression was observed in 94.1%(16/17) of cases exhibiting methylation. FMs of TGFβRⅡwere identified in 5 (62.5%) of the 8 samples with MSIH. In contrast, FMs were not found in MSI -L or microsatellite stable (MSS) cases. CONCLUSION MSIs and FMs of TGFβRⅡmay play an important role in gastric carcinogenesis. HMLH1 methylation is an important modification of the DNA which results in inactivation of hMLH1 and mismatch repair defects which lead to MSIs and FMs of TGFβRⅡ.

Transforming growth factor β receptor Ⅱ expression inexperimental cryptorchidism and apoptosisin spermatogenic cells in rats

Objective: To study the transforming growth factor β receptor Ⅱ (TGFβ-R Ⅱ) expression in experimental cryptorchidism and apoptosis in spermatogenic cells in rats. Methods: The apoptosis of spermatogenic cells was detected by means of the terminal deoxynucleotldyl transferase mediated dUTP nick end lableling method (TUNEL) and the TGFβ-R Ⅱ expression was observed with the immunohistochemistry SABC methods. Results: There was a significant increase in the TGFβ-R Ⅱ expression in unilateral undescended testes (UUTs) compared with that in contralateral descended testes (CDTs, P<0.01). However, there was a significant and time-dependent increase in the mean apoptotic index in UUTs than in CDTs. Conclusion: TGFβ-R Ⅱ may play an important role in spermatogenic cell apoptosis.

Transforming growth factor-β and toll-like receptor-4 polymorphisms are not associated with fibrosis in haemochromatosis

AIM:To investigate the role of genetic polymorphisms in the progression of hepatic fibrosis in hereditary haemochromatosis.METHODS:A cohort of 245 well-characterised C282Y homozygous patients with haemochromatosis was studied,with all subjects having liver biopsy data and DNA available for testing.This study assessed the association of eight single nucleotide polymorphisms(SNPs)in a total of six genes including toll-like receptor 4(TLR4),transforming growth factor-beta(TGF-β),oxoguanine DNA glycosylase,monocyte chemoattractant protein 1,chemokine C-C motif receptor 2 and interleukin-10 with liver disease severity.Genotyping was performed using high resolution melt analysis and sequencing.The results were analysed in relation to the stage of hepatic fibrosis in multivariate analysis incorporating other cofactors including alcohol consumption and hepatic iron concentration.RESULTS:There were significant associations between the cofactors of male gender(P=0.0001),increasing age(P=0.006),alcohol consumption(P=0.0001),steatosis(P=0.03),hepatic iron concentration(P<0.0001)and the presence of hepatic fibrosis.Of the candidate gene polymorphisms studied,none showed a significant association with hepatic fibrosis in univariate or multivariate analysis incorporating cofactors.We also specifically studied patients with hepatic iron loading above threshold levels for cirrhosis and compared the genetic polymorphisms between those with no fibrosis vs cirrhosis however there was no significant effect from any of the candidate genes studied.Importantly,in this large,well characterised cohort of patients there was no association between SNPs for TGF-βor TLR4and the presence of fibrosis,cirrhosis or increasing fibrosis stage in multivariate analysis.CONCLUSION:In our large,well characterised group of haemochromatosis subjects we did not demonstrate any relationship between candidate gene polymorphisms and hepatic fibrosis or cirrhosis.

伴有微卫星不稳定性的散发性结直肠癌转化生长因子 -betaⅡ型受体基因突变的研究(英文)

目的 :为了探讨在散发性结直肠癌的发生过程中转化生长因子βⅡ型受体基因 (RII)的突变与微卫星不稳定性 (RER)间的关系。方法 :我们应用PCR -SSCP -银染方法检测了 5 0例散发性结直肠癌中的RER状态及RII基因突变情况 (近端结肠 19例 ,远端 31例 )。结果 :RER +的共有 13例 (8例在近端 ,5例在远端 ) ,RII基因突变的共有 5例。所有 5例RII基因突变者均同时伴有RER +,而所有RER -病例均无RII基因突变。其中 4例RII基因突变者位于回盲部肿瘤中。结论 :这些数据提示在散发性结直肠癌中 ,尤其是在回盲部肿瘤中 ,TGF - βRII基因的A10 重复序列是微卫星不稳定性的靶点 。

Effects of angiotensin Ⅱ receptor antagonist on expression of collagen Ⅲ,collagen Ⅴ,and transforming growth factor β_1 in the airway walls of sensitized rats

Background Repeated attacks of bronchial asthma lead to different degrees of airway remodeling,the mechanism of which is not yet clear. Some evidences indicate that it is related to the excessive expression of some growth promotion factors. Angiotensin Ⅱ is a polypeptide that may be involved in airway remodeling. To evaluate its role in airway remodeling in asthma,we observed the effects of an angiotensin Ⅱ type 1 receptor antagonist (valsartan) on the expression of collagen Ⅲ,collagen Ⅴ,and transforming growth factor β_1 (TGF-β_1) mRNA and protein in the airway walls of sensitized rats.Methods Forty Wistar rats were randomly divided into 5 groups: control group,sensitized group,and valsartan groups 1,2,and 3. The rats in the sensitized group and in valsartan groups 1,2,and 3 were sensitized and challenged with ovalbumin. Rats in control group were sensitized and challenged with 0.9% NaCl. Rats from valsartan groups 1,2,and 3 were drenched with valsartan (10 μg, 20 μg,or 30 μg,respectively) at the time of the ovalbumin challenges. The expression of collagen Ⅲ,collagen Ⅴ,and TGF-β_1 protein were detected using immunohistochemical method in combination with image analysis methods. The expression of TGF-β_1 mRNA was detected by in situ hybridization. Results The expression in the airways of collagen Ⅲ and collagen Ⅴ was significantly higher in rats from the sensitized group (7.73±0.81, 1.34±0.28) and from valsartan groups 1,2,and 3 (5.73±0.64, 1.13±0.15; 4.96±0.51, 0.98±0.08; 4.43±0.35, 0.93±0.06,respectively) than those in the control group (2.65±0.38, 0.67±0.08,P <0.05). In addition,collagen levels were significantly lower in valsartan groups 1,2,and 3 than those from the sensitized group ( P <0.05). The expression of TGF-β_1 mRNA and protein in the airways was significantly higher in rats from the sensitized group (20.49%±3.46%,29.73%±3.25%) and from valsartan groups 1,2,and 3 (16.47%±1.94%, 19.41%±1.87%; 14.38%±1.58%, 18.29%±1.43%; 12.96%±1.73%, 18.63%±1.11%,respectively) than that from the control group (7.84%±1.61%, 5.63%±1.07%,P <0.05). TGF-β_1 mRNA and protein levels were significantly lower in valsartan groups 1,2,and 3 than that in the sensitized group ( P <0.05). Conclusions Angiotensin Ⅱ receptor antagonist valsartan can suppress synthesis of collagen Ⅲ and collagen Ⅴ by downregulating TGF-β_1 mRNA and protein expression. Valsartan can decrease airway remodeling and could play a role in asthma therapy.

Influence of baicalin on the expression of receptor activator of nuclear factor-κB ligand and osteoprotegerin in human periodontal ligament cells

Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.

高亲和PDGFβR多肽修饰的截短型TβRⅡ的可溶性表达条件优化

目的 探讨高亲和血小板衍生生长因子受体(Platelet derived growth factor-β receptor, PDGFβR)多肽ZPDGFβR修饰的截短型转化生长因子β Ⅱ型受体(Truncated transforming growth factor-β receptor type Ⅱ,tTβRⅡ)的重组蛋白(Z-tTβRⅡ)最佳可溶性表达的条件。方法 将含有原核表达质粒pET28/Z-tTβRⅡ的阳性大肠杆菌(Rossta/pET28-Z-tTβRⅡ)置于LB培养基中培养,接着加入不同浓度的IPTG,使其终浓度为0.2、0.4、0.6、0.8 mmo/L,应用SDS-PAGE技术分析在不同温度时间下(16℃、18 h, 20℃、20 h和37℃、6 h)重组蛋白Z-tTβRⅡ的可溶性表达。结果 Z-tTβRⅡ在16℃、18 h下,0.8 mmol/L IPTG时,诱导后全菌表达约22%和诱导后上清表达约13%;Z-tTβRⅡ在20℃、20 h下,诱导后全菌0.8 mmol/L IPTG时表达约23%,诱导后上清0.2 mmol/L IPTG时表达约14%;Z-tTβRⅡ在37℃、6 h下,0.2 mmol/L IPTG时,诱导后全菌约30%和诱导后上清约20%。结论 Z-tTβRⅡ蛋白最佳表达条件为37℃、6 h、IPTG浓度为0.2 mmo/L。

Effect of substance P on gene expression of transforming growth factor β-1 and its receptors in rat's fibroblasts

Objective: To investigate the effect of substance P (SP) on gene expression of transforming growth factor β-1 (TGFβ-1), transforming growth factor receptor-1 (TGFR-1) and transforming growth factor receptor-2 (TGFR-2) in fibroblasts cultured in vitro from rat’s granulation tissues. Methods: The fibroblasts from the granulation tissues in the skeletal muscle of rat’s hind limbs injured by formaldehyde were cultured in vitro. When different concentrations (10 -9-10 -5 mol/L) of SP were added into the culture medium, the changes of gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the cultured fibroblasts were observed with reverse transcription polymerase chain reaction at different intervals (0, 3, 6, 12 and 24 hours after incubation). Results: The gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the fibroblasts cultured from rat’s granulation tissues was up-regulated by SP. The peak level of the mRNA expression was found at 10 -8 mol/L SP and the up-regulation effect was not found at 10 -5 mol/L and 10 -6 mol/L. The peak levels of gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the fibroblasts treated with SP were achieved at 6 and 12 hours, respectively. Conclusions: SP has up-regulation effect on the gene expression of TGFβ-1, TGFR-1 and TGFR-2 in fibroblasts from rat’s granulation tissues in vitro, and the effect is related to different stimulating concentrations of SP. It may be concerned with proliferation and differentiation of fibroblasts and formation of scar tissues during wound healing.

Effect of Sini decoction on angiotensin Ⅱ, transforming growth factor β_1 and connective tissue growth factor in rats with myocardial fibrosis-induced banding of the abdominal aorta

OBJECTIVE: To investigate the effect of Sini decoction on rats with myocardial fibrosis induced by banding the abdominal aorta, and explore the mechanism underlying its actions on angiotensin Ⅱ(Ang Ⅱ), transforming growth factor-β_1(TGF-β_1)and connective tissue growth factor(CTGF).METHODS: Forty-eight male Sprague-Dawley rats were randomly divided into sham operation, model, Captopril, and Sini decoction groups. The models were established by the partial banding of the abdominal aorta according to Doering's method.Eight weeks later, heart weight indexes were calculated; hemodynamic changes of the hearts were tested; changes in myocardial tissue morphology were observed by Masson staining; and myocardial collagen volume fraction was calculated. Enzyme-linked immunosorbent assay was used to measure the concentration of Ang Ⅱ in serum. The expression of TGF-β_1 and CTGF were determined by immunohistochemistry and Western blotting.RESULTS: Compared with the sham operation group, the heart weight index, collagen volume fraction of the myocardium, serum levels of Ang Ⅱ,and the expression of myocardial TGF-β_1 and CTGF in the model group were significantly increased(P < 0.05). Compared with the model group, the heart weight index, collagen volume fraction of the myocardium, serum levels of Ang Ⅱ, and the expression of myocardial TGF-β_1 and CTGF in all treatment groups were significantly reduced(P < 0.05).CONCLUSION: Sini decoction reduced AngⅡ level and inhibited the expression of myocardial TGF-β_1 and CTGF, which may explain the mechanism of its protective effect on myocardium with fibrosis.

Flagellin of Pseudomonas aeruginosa induces transforming growth factor beta 1 expression in normal bronchial epithelial cells through mitogen activated protein kinase cascades

Background Acute lung infection due to Pseudomonas aeruginosa （P. Aeruginosa） is a serious problem, especially in patients with structural lung conditions or immune compromised hosts, leading to an overwhelming threat with a high risk of morbidity and mortality. As an outcome of infection, fibrosis can be linked with chronic lung diseases. But some fibrotic manifestations, such as an irreversible decrease of lung function and fibrous bands seen on chest imaging, have been found after an acute infection with P. Aeruginosa. Fibrogenesis/remodeling resulting from acute lung infection by P.aeruginosa is rarely reported. This study was designed to explore the relation between fibrogenesis/remodeling and acute infection by P. Aeruginosa in vitro. We used flagellin protein from P. Aeruginosa, a key initiator of acute P.aeruginosa lung infection, to elucidate mechanisms by which acute lung infection with P. Aeruginosa can cause fibrogenesis/remodeling.Methods We studied the effect of flagellin from P. Aeruginosa （flagellin for short） on the transforming growth factor beta 1 （TGF-β1） and interleukin-8 （IL-8） expression, and the possible involvement of the signaling pathway, tumor necrosis factor receptor-associated factor 6 （TRAF6）/mitogen activated protein kinase （MAPK） pathway. Flagellin was purified from the P. Aeruginosa standard strain, PAO1. Normal bronchial epithelial cells BEAS-2B were challenged with different concentrations of flagellin, and cell viability assessment was performed by cell counting kit-8. BEAS-2B cells were incubated with flagellin with the specific MAPK inhibitors or TRAF6 siRNA. Cell lysates and the cultured supernatant were collected. The level of TGF-β1 and IL-8 were detected by enzyme-linked immunosorbant assay （ELISA）. Western blotting was used to detect the protein levels of MAPK signal proteins p38, c-Jun NH2-terminal kinase （JNK） and extracellular regulated kinase （ERK）.Results Expression of TGF-β1 in BEAS-2B cells was elevated by flagellin vs. Control groups （（104.3±20.8） vs.（44.6±4.4） pg/ml （P 〈0.01）） and was ablated by either p38 or JNK inhibitors compared with flagellin treatment （（45.1±18.8）vs. （104.3±20.8） pg/ml and （48.1±20.8） vs. （104.3±20.8） pg/ml, respectively （P 〈0.05））. Flagellin also elevated the expression of IL-8 in BEAS-2B cells vs. The control groups （（554.9±57.7） vs. （51.4±2.2.9） pg/ml （P 〈0.01））, and p38 MAPK inhibitors weaken the expression by flagellin （（301.1 ±155.1） vs. （554.9±57.7） pg/ml （P 〈0.05））. Western blotting revealed that all three MAPK proteins, p38, JNK and ERK were activated by flagellin challenge in an early phase, respectively in 15 minutes （P 〈0.01）, 30 minutes （P 〈0.01） and 15 minutes （P 〈0.01）. TRAF6 siRNA which decreased expression of TRAF6, altered the activation of JNK, p38, and ERK following flagellin treatment, but its influence on the expression of TGF-β1 and IL-8 has no statistical significance.Conclusions Flagellin from P. Aeruginosa PAO1 induces TGF-β1 expression in normal bronchial epithelial cells,BEAS-2B, through the MAPK signal cascade in vitro. It suggests that the fibrogenesis/remodeling process may be initiated from an early stage of acute lung infection due to P. Aeruginosa.

TGF-βRⅡ和Smad4蛋白在葡萄膜黑色素瘤中的表达

目的研究转化生长因子Ⅱ型受体(TGFβRⅡ)及其下游的抑癌基因Smad4蛋白在葡萄膜黑色素瘤中的表达。方法应用免疫组织化学SP法对24例葡萄膜黑色素瘤瘤组织中TGFβRⅡ和Smad4蛋白的表达进行检测。结果在24例葡萄膜黑色素瘤组织切片中,可见瘤细胞TGFβRⅡ阳性12例(50%),Smad4阳性11例(45.8%),两者均阳性5例,两者均阴性6例。结论葡萄膜黑色素瘤组织中存在TGFβRⅡ和/或Smad4的蛋白表达异常,可能与葡萄膜黑色素瘤的发病有关。

干扰素γ及血管紧张素Ⅱ对大鼠血管平滑肌细胞表达转化生长因子β1型受体的影响

转化生长因子β1(TGF β1)刺激细胞外基质 (ECM)生成 ,作者观察了血管紧张素Ⅱ(AngⅡ)及γ干扰素 (IFN γ)对大鼠血管平滑肌细胞 (VSMC)TGF βⅠ型受体(TβR I)表达的影响。培养大鼠VSMC ,以Western印迹法观察AngⅡ(10 -7mol/L)及IFN γ(5 0 0U/ml)作用 2 4h时对VSMCTβR I表达的影响。发现AngⅡ组TβR I表达明显高于对照组 (OD值 10 3 0 6± 9 34vs 6 2 2 4±4 39,P <0 0 1) ,IFN γ单独孵育对TβR I表达无影响 ,但可以明显抑制AngⅡ引起的TβR I表达 (OD值 81 37± 5 87)。表明AngⅡ刺激大鼠VSMCTβR I表达 ,IFN

丹参酮ⅡA对高血压大鼠肥厚心肌TGF-β_1/Smads信号通路的影响

目的研究丹参酮(Tanshinone,TSN)ⅡA对压力超负荷大鼠肥厚心肌血管紧张素1型受体(angiotensin Ⅱtype 1 receptor,AT1R)、转化生长因子β1(transforming growth factor-β1,TGF-β1)与其胞内信号蛋白Smads基因表达的影响,探讨TSNⅡA抑制高血压左心室肥厚的分子机制。方法 SD大鼠行腹主动脉缩窄术建立高血压左室心肌肥厚模型,术后4周将手术大鼠随机分为模型组、丹参酮低、高剂量组[10、20mg/(kg.d)]、缬沙坦组[10mg/(kg.d)],每组8只;另有8只作为假手术组。用药8周后检测各组尾动脉压,取左心室组织检测左心室质量指数(left ventricular mass index,LVMI)、病理切片HE染色测量心肌纤维直径(myocardial fiber dimension,MFD);采用逆转录-聚合酶链式反应(reverse transcription-polymerase chain raction,RT-PCR)检测AT1R mRNA的表达水平,免疫印迹法(Western blot)分别检测TGF-β1及其胞内信号蛋白Smad-3、4、7的蛋白水平。结果 (1)丹参酮低、高剂量组血压没有变化,并显著高于假手术组和缬沙坦组(P<0.01)。(2)丹参酮低、高剂量组和缬沙坦组的LVMI、MFD均显著低于模型组(P<0.01)。(3)心肌肥厚时AT1R、TGF-β1和Smad-3的表达显著增加(P<0.01),高剂量TSNⅡA和缬沙坦都可使肥厚心肌的AT1R mRNA和TGF-β1、Smad-3蛋白水平明显下调(P<0.01),缬沙坦对TGF-β1的下调作用较丹参酮明显(P<0.05)。(4)低、高剂量的丹参酮和缬沙坦均可以使Smad-7蛋白的表达显著上调(P<0.01),丹参酮高剂量组上调作用明显超过缬沙坦组(P<0.05)。结论丹参酮ⅡA对心肌肥厚的抑制作用是非血压依赖性的,其对高血压心肌肥厚的抑制作用可能与抑制AT1R mRNA表达、阻滞TGF-β1/Smads的信号转导有关。

肺泡Ⅱ型TGFβ_1和PDGF基因表达及其在肺纤维化中的意义

目的 :研究转化生长因子 β1(TGFβ1)和血小板源性生长因子 (PDGF)在肺泡Ⅱ型细胞中的表达及其在肺纤维化过程中的意义。方法 :分离培养正常成年大鼠肺泡Ⅱ型细胞 ,建立大鼠矽肺模型 ,用原位杂交和免疫组化技术检测体外培养的和矽肺病变中的肺泡Ⅱ型细胞TGFβ1和PDGF BmRNA和蛋白的表达。结果 :(1)体外培养的肺泡Ⅱ型细胞免疫组化染色TGFβ1强阳性 ,PDGF B弱阳性 ;原位杂交TGFβ1和PDGF BmRNA均为阳性。 (2 )大鼠矽肺实验组增生的肺泡Ⅱ型细胞明显表达TGFβ1和PDGF BmRNA和蛋白 ;对照组仅有部分正常肺泡Ⅱ型细胞TGFβ1mRNA呈弱阳性。结论 :增生的肺泡Ⅱ型细胞有TGFβ1和PDGF B基因表达 ,其在矽肺纤维化病变中可能起重要作用。

TGF-β增强rhBMP-2诱导成骨中Ⅰ、Ⅱ型胶原mRNA及碱性磷酸酶的表达

目的 :对TGF β增强rhBMP 2诱导成骨中CollagenⅠ、ⅡmRNA及碱性磷酸酶 (ALP)的表达进行研究。方法 :BALB/c小鼠 110只随机分 2组 ,每组 5 5只。rhBMP 2 /TGF β为实验组 ,rhBMP 2为对照组 ,于术后 3～2 1d 8个时间点取材 ,用原位杂交方法对新生骨组织中的Ⅰ、Ⅱ型胶原mRNA进行检测 ;对ALP活性进行定量分析 ,观察 2组在诱导成骨中CollageⅠ、ⅡmRNA及ALP的表达情况。结果 :(1)Ⅱ型胶原mRNA的出现是和成软骨、软骨细胞的出现相伴随的 ;(2 )做为成骨细胞成熟标志物的Ⅰ型胶原mRNA、ALP在软骨形成期即有表达 ,随着成骨细胞的出现 ,骨组织的形成Ⅰ型胶原mRNA仍表现为高表达 ,而ALP的表达则呈下降趋势 ;(3 )实验组CollagenⅠ、ⅡmRNA及ALP的表达早于对照组。结论 :TGF β增强了rhBMP 2诱导成骨中CollagenⅠ、ⅡmRNA及ALP的表达。

miR-10b靶向TGFBR1/SMAD3通路对特发性矮小症的软骨细胞增殖、肥大的影响机制

目的研究miR-10b对特发性矮小症(ISS)的影响及作用机制。方法收集ISS患儿(ISS组)和体检健康儿童(健康对照组)各54例,qPCR检验血清miR-10b表达量,分析ISS组患儿血清miR-10b表达与患儿临床资料的关系。采用miR-10b inhibitor、si-TGFBR1及各自阴性对照转染C28/I2细胞,利用CCK-8实验检测C28/I2细胞增殖能力,Western blot检测侏儒相关转录因子2(RUNX2)、X型胶原α1链(COL10A1)、转化生长因子β受体1(TGFBR1)、SMAD3、pSMAD3蛋白表达量。在StarBase数据库筛选miR-10b靶点,利用双萤光素酶报告基因实验验证miR-10b与TGFBR1的靶向关系。结果ISS组血清miR-10b表达量高于健康对照组,且miR-10b表达越高,患儿的身高、IGF-1、骨特异性碱性磷酸酶的下降越明显(P<0.05)。与NC组相比,miR-10b inhibitor组细胞增殖能力升高,RUNX2、COL10A1、TGFBR1、pSMAD3蛋白表达上调(P<0.05);StarBase数据库提示miR-10b存在TGFBR1的结合位点,双萤光素酶报告基因实验证实两者结合。与si-NC相比,si-TGFBR1组TGFBR1表达量下调,细胞增殖能力下降(P<0.05)。结论miR-10b通过靶向TGFBR1/SMAD3通路在特发性矮小症中抑制软骨细胞的增殖、肥大。

丹参酮ⅡA抑制心肌细胞的纤维化

背景:转化生长因子β-Smads信号通路是心肌纤维化的关键通路;丹参酮ⅡA具有抑制心肌纤维化作用。目的:验证丹参酮ⅡA对转化生长因子β1致心肌纤维化的作用并探讨其机制。方法:取出生24h内的SD大鼠心脏,利用酶消化法结合差速贴壁体外培养心肌成纤维细胞。取上述第3代心肌成纤维细胞,用5μg/L转化生长因子β1培养15,30,60,120min或6,12,24h后收集细胞,用不同浓度(10-5mol/L、10-4mol/L)丹参酮ⅡA预处理2h后再加入5μg/L转化生长因子β1培养120min或24h后收集细胞,并设空白对照组。免疫细胞化学染色法进行细胞鉴定,反转录聚合酶链反应检测结缔组织生长因子及Ⅰ型胶原蛋白mRNA表达,Western Blot检测Smad7及磷酸化Smad3蛋白表达。免疫组织化学染色及免疫荧光法检测磷酸化Smad3、结缔组织生长因子及Ⅰ型胶原蛋白表达。结果与结论:转化生长因子β1在一定范围内以时间依赖方式诱导结缔组织生长因子、Ⅰ型胶原、磷酸化Smad3及Smad7的表达,刺激终末结缔组织生长因子、Ⅰ型胶原mRNA的表达量明显上升(均P<0.01);磷酸化Smad3及Smad7蛋白表达量在刺激后1h达到峰值,表达量显著增加(均P<0.01)。高浓度丹参酮ⅡA预处理可显著下调磷酸化Smad3、结缔组织生长因子及Ⅰ型胶原表达(均P<0.01)。两种浓度的丹参酮ⅡA预处理均可上调Smad7蛋白表达(P<0.05,P<0.01)。提示丹参酮ⅡA对心肌纤维化有抑制作用,可能与其上调Smad7蛋白表达,抑制转化生长因子β1诱导的Smad3磷酸化,部分阻断转化生长因子β1-Smads信号通路有关。