Expression analysis of a-smooth muscle actin and tenascin-C in the periodontal ligament under orthodontic loading or in vitro culture

α-smooth muscle actin （α-SMA） and tenascin-C are stress-induced phenotypic features of myofibroblasts. The expression levels of these two proteins closely correlate with the extracellular mechanical microenvironment. We investigated how the expression of α-SMA and tenascin-C was altered in the periodontal ligament （PDL） under orthodontic loading to indirectly reveal the intrinsic mechanical microenvironment in the PDL. In this study, we demonstrated the synergistic effects of transforming growth factor-β1 （TGF-β1） and mechanical tensile or compressive stress on myofibroblast differentiation from human periodontal ligament cells （hPDLCs）. The hPDLCs under higher tensile or compressive stress significantly increased their levels of α-SMA and tenascin-C compared with those under lower tensile or compressive stress. A similar trend was observed in the tension and compression areas of the PDL under continuous light or heavy orthodontic load in rats. During the time-course analysis of expression, we observed that an increase in α-SMA levels was matched by an increase in tenascin-C levels in the PDL under orthodontic load in vivo. The time-dependent variation of α-SMA and tenascin-C expression in the PDL may indicate the time-dependent variation of intrinsic stress under constant extrinsic loading.

Dynamic Variation of RAS on Silicotic Fibrosis Pathogenesis in Rats

The dynamic variation of renin-angiotensin system (RAS) in silicosis remains unclear.Seventy Wistar rats were divided into 7 groups including control group,silicosis groups (inhaling SiO2 for 2,4,8,16 and 24 weeks,respectively) and Captopril (Cap) group.Rat lung primary fibroblasts were divided into control group,SiO2-stimulated group (0,0.5,1,3,6,12,24 and 48 h) and Cap group.The silicotic nodules were formed and collagens were deposited gradually in silicosis group observed by haematoxylin and eosin (HE) staining and Van Gieson (VG) staining.Cap relieved the lung fibrosis and collagen deposition.Immunohistochemistry indicated the positive expression of α-smooth muscle actin α-SMA) was increased gradually in silicotic rat lung tissue.Western blotting revealed the expression of collagen type Ⅰ(Col Ⅰ) and α-SMA was up-regulated in silicotic rat lung tissue and fibroblasts stimulated by SiCh.Cap decreased the expression of Col Ⅰ and α-SMA in silicotic rat lung tissue and fibroblasts stimulated by SiCh.Western blotting also demonstrated the expression of angiotensin-converting enzyme (ACE) and angiotensin Ⅱ type 1 receptor (ATI) was increased,and the expression of ACE2 and Mas was decreased gradually in silicotic rat lung tissue and fibroblasts stimulated by SiCh.ELISA showed the serum levels of ACE and angiotensin Ⅱ(Ang Ⅱ) were also increased and ACE2 and Ang (1 -7) were decreased in the silicosis group.Treatment with Cap decreased the expression levels of ACE,Ang Ⅱ and ATI,and increased the expression levels of ACE2,Ang (1-7) and Mas.These findings suggested that an imbalance between ACE-Ang Ⅱ-AT1 axis and ACE2-Ang (l-7)-Mas axis may participate in the development of silicosis.

Effects of pharmacological serum from normal and liver fibrotic rats on HSCs

AIM: To make drug sera of Salvia miltiorrhiza and Yigankang, both of which are Chinese herbs that activate bleeding and eliminate stasis, in normal rats and those with liver fibrosis, respectively. To investigate and compare the effects of the two different drug sera on the proliferation and activation of hepatic stellate cells (HSCs). METHODS: Some rats were induced with liver fibrosis: 40% carbon tetrachloride (CCI4) subcutaneous injection, twice a week for 9 wk. Salvia miltiorrhiza, Yigankang, colchicines and normal saline were administered into the stomachs of normal rats and those with liver fibrosis. Drug sera were extracted 5 d later. HSCs in vitro were cultivated in different drug sera for 24 h. The rates of proliferation and expression of a-smooth muscle actin (α-SMA) were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and immunocyt-ochemistry stain, respectively. RESULTS: The drug sera from normal and liver fibrotic rats could be used to cultivate HSCs and to observe the effects of the corresponding components of herbs on HSCs. Salvia miltiorrhiza and Yigankang had better inhibitory effects on HSCs than colchicines (MTT: normal drug serum: Salvia miltiorrhiza 0.42 ±0.08, Yigankang 0.32±0.10 vs colchicines 0.45±0.12 pathological drug serum: Salvia miltiorrhiza 0.33±0.02, Yigankang 0.26±0.01 vs colchicines 0.41±0.09. P<0.05). The drug sera of Salvia miltiorrhiza, Yigankang from liver fibrotic rats had a stronger inhibitory effect than the same ones from normal rats (MTT: Salvia miltiorrhiza: normal drug serum 0.42±0.08 vs pathological drug serum 0.33±0.02. Yigankang: normal drug serum 0.32±0.10 vs pathological drug serum 0.26±0.01. P<0.05) CONCLUSION: Salvia miltiorrhiza and Yigankang could inhibit the expression of a-SMA and the proliferation of HSCs. The drug sera from normal and liver fibrotic rats had different effects on HSCs, probably due to different metabolic processes, effective components and different quantities of drug contents in drug sera from rats with different states of liver.

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.

Depressant effect and mechanism of atorvastatin on the chronic rejection of aortic allograft in rats

Objective To investigate the depressant effect and mechanism of atorvastatin on the chronic rejection of aortic allograft in rats. Methods： The models of abdominal aorta transplantation were made with micro-surgery in rats. The recipients were divided into three groups： allograft control group, atorvastatin-treated group and isograft control group. Vascular intimal thickness in all of the groups were observed by histological examination. The expression of PCNA and α-SMA were determined by immunohistochemistry. The content of nitric oxide was determined by nitrate reductase chromatometry. Results： The vascular intimal thickness in rats of atorvastatin-treated group （11.60% ± 2.40% ） were lower than those in allograft control group （34.60 % ± 6.40 % ; P 〈 0.05） and higher than those in isograft control group （1.15 % ± 0.65 %; P〈 0.05 ）. The expression level of PCNA was decreased in atorvastatin-treated group （4.80% ± 0.80% ） than allograft control group （18.40% ± 1.80% ; P〈0.05） and higher than isograft group （1.20% ± 0.40% ; P〈0.05）. Conclusion： The expression of PCNA in the transplant aorta could be suppressed by atorvastatin, which resalted in relief of chronic rejection of aortic allograft.

Effects of interleukin-10 on activation and apoptosis of hepatic stellate cells in fibrotic rat liver

AIM： TO study the effects of interleukin-10 （IL-10） on the expression of o-smooth muscle actin （α-SMA）, nuclear factor-κB（NF-κB） and Fas/Fas ligand （FasL） in hepatic stellate cells of experimental rats with hepatic fibrosis. METHODS： Sixty clean SD rats were randomly divided into control group （group N）, liver fibrotic group （group C） and IL-10 treatment group （group I）. Control group received intraperitoneal injection of saline （2ml·kg^-1）, twice a week. Fibrotic group was injected intraperitoneally with 50% carbon tetrachloride （CCh） （2 ml·kg^-1）, twice a week. IL-10 treatment group was given IL-10 at a dose of 4 pg·kg^-1 20 minutes before CCl4 administration from the third week. Hepatic stellate cells （HSCs） were isolated from these rats at the seventh and eleventh weeks during the course of liver fibrosis, respectively. The expression of α-SMA and NF-κB in HSCs was measured by S-P immunohistochemistry. The expression of Fas and FasL mRNA was measured by RT-PCR. Furthermore, liver tissues were harvested from three groups at the same time. RESULTS： The CCh- induced experimental rat hepatic fibrosis model was established successfully. The purity of extracted hepatic stellate cells was about 95% and the yield of hepatic stellate cells was 1.2-2.3×10^6/g liver tissue averagely. The positive expression of α-SMA and NF-κB was 36.5% and 28.5% respectively in group N. The positive levels of α-SMA and NF-κB were increased significantly in group C compared to group N （P〈0.01）. The positive signals decreased significantly （P〈0.05） in group I. In the 11^th week, the HSCs of group I became round with visible pyknotic nuclei. The expression of NF-κB in group C was significantly increased in a timedependentmanner （P〈0.01）, but there was no difference in the α-SMA expression （P〉0.05）. The mRNA of Fas and FasL in group C was significantly increased in a timedependent manner compared to that in control group. After treated with IL-10, the expression level of Fas and FasL was higher in group I than in group C. CONCLUSION： The positive expression of α-SMA and NF-κB in hepatic stellate cells is decreased by ectogenic IL-10 in liver fibrosis induced by CCh. The expression of Fas and FasL is increased in the course of liver fibrosis, and is further increased by IL-10. IL-10 could inhibit the activation of HSCs and cause apoptosis of activated HSCs.

Emodin protects rat liver from CCl_4-induced fibrogenesis via inhibition of hepatic stellate cells activation

AIM： To investigate the role of emodin in protecting the liver against fibrogenesis caused by carbon tetrachloride （CCh） in rats and to further explore the underlying mechanisms. METHODS： Rat models of experimental hepatic fibrosis were established by injection with CCh; the treated rats received emodin via oral administration at a dosage of 20 mg/kg twice a week at the same time. Rats injected with olive oil served as a normal group. Histopathological changes were observed by hematoxylin and eosin staining. The activities of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） in serum and hepatic hydroxyproline content were assayed by biochemical analyses. The mRNA and protein relevant to hepatic stellate cell （HSC） activation in the liver were assessed using real-time reverse transcription-polymerase chain reaction （RT-PCR）, immunohistochernistry, western blotting and enzymelinked immunosorbent assay.RESULTS： The degree of hepatic fibrosis increased markedly in the CCh group compared to the normal group （P 〈 0.01）, and decreased markedly in the emodin group compared to the CCI4 group according to METAVIR scale （P 〈 0.01） compared with those in the normal control group （51.02 ± 10.64 IU/L and 132.28 ± 18.14 IU/L）. The activities of serum ALT and AST were significantly higher in rats injected with CCh （289.25 ± 68.84 IU/L and 423.89 ± 35.67 IU/L, both P 〈 0.05）. The activities of serum ALT and AST were significantly reduced by administration of emodin （176.34 ± 47.29 IU/L and 226.1 ± 44.52 IU/L, both P 〈 0.05）. Compared with the normal controls （54.53 ± 13.46 mg/g）, hepatic hydroxyproline content was significantly higher in rats injected with CCI4 （120.27 ± 28.47 mg/g, P 〈 0.05）. Hepatic hydroxyproline content was significantly reduced in the rats treated with emodin at 20 mg/kg （71.25 ± 17.02 mg/g, P 〈 0.05）. Emodin significantly protected the liver from injury by reducing serum AST and ALT activities and reducing hepatic hydroxyproline content. The mRNA levels of transforming growth factor-β1 （TGF-β1）, Smad4 and α-SMA in liver tissues were significantly down-regulated in SD rats that received emodin treatment. Furthermore, significant down-regulation of serum TGF-β1 protein levels and protein expression of Smad4 and α-SMA in liver tissues was also observed in the rats. Emodin inhibited HSC activation by reducing the abundance of TGF-β1 and Smad4. CONCLUSION： Emodin protects the rat liver from CCI4-induced fibrogenesis by inhibiting HSC activation. Emodin might be a therapeutic antifibrotic agent for the treatment of hepatic fibrosis.

Daikenchuto (Da-Jian-Zhong-Tang) ameliorates intestinal fibrosis by activating myofibroblast transient receptor potential ankyrin 1 channel

AIM To investigate the anti-fibrotic effects of the traditional oriental herbal medicine Daikenchuto(DKT) associated with transient receptor potential ankyrin 1(TRPA1) channels in intestinal myofibroblasts. METHODS Inflammatory and fibrotic changes were detected in a2,4,6-trinitrobenzenesulfonic acid(TNBS) chronic colitis model of wild-type and TRPA1-knockout(TRPA1-KO) mice via pathological staining and immunoblotting analysis.Ca^(2+) imaging experiments examined the effects of DKT and its components/ingredients on intestinal myofibroblast(In Myo Fib) cell TRPA1 channel function.Profibrotic factors and transforming growth factor (TGF) -β1-associated signaling were tested in an In Myo Fib cell line by q PCR and immunoblotting experiments.Samples from non-stenotic and stenotic regions of the intestines of patients with Crohn’s disease (CD) were used for pathological analysis. RESULTS Chronic treatment with TNBS caused more severe inflammation and fibrotic changes in TRPA1-KO than in wild-type mice.A one-week enema administration of DKT reduced fibrotic lesions in wild-type but not in TRPA1-KO mice.The active ingredients of DKT,i.e.,hydroxyα-sanshool and 6-shogaol,induced Ca^(2+) influxes in In Myo Fib,and this was antagonized by co-treatment with a selective TRPA1 channel blocker,HC-030031.DKT counteracted TGF-β1-induced expression of TypeⅠcollagen andα-smooth muscle actin (α-SMA) ,which were accompanied by a reduction in the phosphorylation of Smad-2 and p38-mitogen-activated protein kinase (p38-MAPK) and the expression of myocardin.Importantly,24-h incubation with a DKT active component Japanese Pepper increased the m RNA and protein expression levels of TRPA1 in In Myo Fibs,which in turn negatively regulated collagen synthesis.In the stenotic regions of the intestines of CD patients,TRPA1 expression was significantly enhanced.CONCLUSION The effects of DKT on the expression and activation of the TRPA1 channel could be advantageous for suppressing intestinal fibrosis,and benefit inflammatory bowel disease treatment.

Epigallocatechin-3-gallate suppresses transforming growth factor-beta signaling by interacting with the transforming growth factor-beta typeⅡreceptor

AIM: To investigate the(-)-epigallocatechin-3-gallate(EGCG) binding to transforming growth factor-β(TGF-β) type Ⅱ receptor(TGFRⅡ).METHODS: The expression of α-smooth muscle actin(α-SMA) was used as a marker for fibrotic change inhuman lung fibroblast MRC-5 cells. The α-SMA expression level was determined by western blotting and immunohistological analysis. We examined whether the anti-fibrotic effects of EGCG on MRC-5 cells was dependent on antioxidant mechanism by using edaravone and N-acetylcysteine(NAC). The suppression effects of EGCG on Smad2/3 activation were studied by confocal fluorescence microscopy. The binding of EGCG to recombinant TGFRⅡ protein was analyzed by immunoprecipitation and affinity chromatography.RESULTS: When MRC-5 cells were treated with TGF-β, EGCG decreased the expression of α-SMA in a dose dependent manner, whereas catechin did not influence the α-SMA expression in the cells. Except for EGCG, antioxidant compounds(e.g., edaravone and NAC) had no effects on the TGF-β-induced α-SMA expression. Nuclear localization of phosphorylated Smad2/3 was observed after TGF-β treatment; however, EGCG treatment attenuated the nuclear transportation of Smad2/3 in the presence or absence of TGF-β. After a TGFRⅡ expression vector was introduced into COS-7 cells, cell lysates were untreated or treated with EGCG or catechin. The immunoprecipitation experiments using the lysates showed that EGCG dose-dependently bound to TGFRⅡ and that catechin did not at all. Affinity chromatography study indicated that EGCG would bind to TGFRⅡ.CONCLUSION: Our results demonstrate that EGCG interacts with TGFRⅡ and inhibits the expression of α-SMA via the TGF-β-Smad2/3 pathway in human lung fibroblast MRC-5 cells.

运动性低血睾酮大鼠某些功能的变化及补肾中药效果的观察

以大鼠为对象 ,目的在于观察运动性低血睾酮状态下 ,机体血睾酮浓度及骨骼肌蛋白质合成代谢的变化 ,并就补肾中药对上述变化的作用加以研究。结果发现 :运动性低血睾酮状态下 ,大鼠的血清睾酮浓度明显低于对照组 (P<0 .0 5 ) ;服用补肾中药的大鼠则没有明显变化 ;运动性低血睾酮组大鼠股四头肌中α- actin基因表达较正常有所下降 (为正常的 78% ) ,而服用补肾中药则可避免这种下降 (为正常的 10 2 % )。认为 :补肾中药的确可以避免大强度耐力运动造成运动性血睾酮浓度下降及骨骼肌α-actin基因表达受抑的现象。

根据mRNA稳定性推断死亡时间的研究

目的检测大鼠肺、胸肌β肌动蛋白(β-actin)mRNA在死后不同时间的表达,为死亡时间的推断寻找新的指标。方法大鼠断颈处死后于21℃温度控制系统模拟死后改变,在不同时间点抽提相应组织总RNA,利用RT-PCR技术检测β-actinmRNA的表达水平变化并对扩增产物进行半定量分析。结果大鼠肺β-actinmRNA于死后12d仍可检出,胸肌在死后8d的检测呈阴性。β-actinmRNA在肺脏和胸肌的稳定性呈现器官差异性和时间差异性。结论观察死后肺、胸肌β-actinmRNA的变化,可为死亡时间推断提供客观依据。

转化生长因子β1和Snail1参与糖尿病大鼠肾小管上皮细胞向间充质细胞转变

本文旨在观察转化生长因子β1(transforming growth factor-β1,TGF-β1)和锌指转录因子Snail1在糖尿病(diabetes mellitus,DM)大鼠肾组织中的表达,并初步探讨它们与肾小管上皮细胞向间充质细胞转变的关系。链脲佐菌素(streptozotocin,STZ)诱发大鼠DM,按病程分为2、4、8、12、16、20、24周、16周胰岛素治疗(16wA)、20周胰岛素治疗(20wA)和24周胰岛素治疗(24wA)组(n=6)。其中胰岛素治疗组动物从第13周起用胰岛素控制血糖至正常水平,每一时点均设鼠龄匹配的正常对照组。测定各组血糖、24h尿蛋白、血肌酐(serumcreatinine,Scr)、肾脏指数。PAS染色光镜观察肾脏病理学改变。免疫组织化学检测肾脏Snail1、TGF-β1、α-平滑肌肌动蛋白(α-smoothmuscleactin,α-SMA)、E-钙黏素和纤连蛋白(fibronectin,FN)的表达;Westernblot检测肾皮质Snail1、TGF-β1和E-钙黏素蛋白表达。RT-PCR检测肾皮质Snail1和E-钙黏素mRNA表达。结果显示:(1)DM各组大鼠的血糖、24h尿蛋白、Scr、肾脏指数均较正常对照组明显升高(P<0.05,P<0.01),胰岛素治疗组大鼠上述指标均较DM组显著降低(P<0.01)。(2)TGF-β1和Snail1免疫组织化学阳性染色见于DM各组大鼠肾小管,正常对照组未见阳性表达,胰岛素治疗组大鼠弱阳性表达,并随治疗时间延长而减少。从16周开始在DM大鼠肾小管上皮细胞可见α-SMA蛋白阳性表达,胰岛素治疗组大鼠未见α-SMA蛋白表达;DM组大鼠E-钙黏素蛋白阳性染色明显少于正常对照组。(3)DM组大鼠肾皮质TGF-β1和Snail1蛋白以及Snail1mRNA表达较正常对照组显著增高(P<0.01),胰岛素治疗组大鼠则显著低于DM组(P<0.01);DM组E-钙黏素mRNA和蛋白表达与TGF-β1和Snail1呈相反变化。结果提示,TGF-β1和Snail1可能参与DM大鼠肾小管上皮细胞向间充质细胞转变,胰岛素治疗可抑制两者表达并阻断肾小管上皮细胞向间充质细胞转变。

灯盏花素对单侧输尿管梗阻大鼠肾间质纤维化的保护作用

目的观察灯盏花素对单侧输尿管梗阻(UUO)大鼠肾脏间质纤维化的保护作用及机制。方法将72只Wistar大鼠随机均分为假手术组、UUO组和灯盏花素组。后两组大鼠结扎并剪断左侧输尿管制作UUO模型,假手术组仅游离左侧输尿管后缝合。灯盏花素组于手术前1d至处死当天给予灯盏花素注射液[100mg/(kg.d)]腹腔注射(2.5ml/次,2次/d)。假手术组及UUO组用同体积生理盐水腹腔注射。采用HE染色观察术后4、7、14d肾脏组织的病理改变,免疫组化及Western blotting检测转化生长因子β1(TGF-β1)、α-平滑肌肌动蛋白(α-SMA)在肾脏的表达。结果假手术组的各时间点肾组织未见病理改变。UUO组术后4、7d,肾间质相对面积增加,且有炎性细胞浸润;术后14d可见肾小管明显扩张,肾间质明显纤维化。与同时间点的UUO组相比,灯盏花素组肾间质相对面积明显下降。与假手术组比较,UUO组和灯盏花素组的TGF-β1和α-SMA蛋白表达水平均有明显增加(P<0.01),但灯盏花素组的表达低于UUO组(P<0.05)。结论灯盏花素可以通过下调TGF-β及α-SMA的表达减轻UUO术后肾脏间质纤维化。

糖尿病大鼠肾小球蛋白激酶Cα表达与肾病发病关系的研究

目的 :观察四氧嘧啶诱发的糖尿病大鼠肾小球中蛋白激酶Cα(PKCα)、转化生长因子 - β1(TGF - β1)和α-平滑肌肌动蛋白 (α -SMA)表达的动态变化 ,探讨 3者之间相互关系以及与肾损害之间的关系。方法 :将大鼠随机分为正常对照组 (A组 ) ,糖尿病 1周组 (B组 ) ,糖尿病 1月组 (C组 )和糖尿病 2月组 (D组 )。用免疫组化和Western印迹法检查PKCα ,TGF - β1和α -SMA在肾小球的表达情况。光镜观察肾组织的形态改变 ,生化法测定大鼠血糖 ,血脂 ,血尿肌酐以及尿蛋白。结果 :糖尿病各组肾小球PKCα和TGF - β1的表达多于正常组 (P <0 0 5 ) ,糖尿病各组PKCα,TGF - β1和α -SMA 3者间呈正相关 ,并且与肾脏病变程度呈正相关。结论 :糖尿病早期肾组织PKCα表达持续增加 ,可使肾小球滤过率和滤过膜通透性增加 ,参与了肾病早期蛋白尿的发生机制 ,使TGF - β1增多并诱导α-SMA的表达 ,标志着肾脏固有细胞激活及表型转变和肾脏组织学改变。

锌与睾酮对力竭性游泳大鼠骨骼肌的影响

动态观察了缺锌和缺锌后补锌以及补充睾酮对大鼠力竭性游泳前后骨骼肌的影响。结果显示,缺锌引起大鼠体重、体长、尾长、趾长伸肌重量、肌四头肌深层肌总RNA含量的明显降低。缺锌影响骨骼肌的代谢速率,阻碍力竭性游泳后骨骼肌总蛋白和总RNA含量的升高,并引起骨骼肌F肌动蛋白的下降,G-肌动蛋白的异常升高。补充睾酮,对缺锌造成的影响无改善作用。缺锌大鼠经过补锌,上述各项指标能恢复或基本恢复。实验还表明,缺锌可影响运动后骨骼肌的恢复。锌缺乏时骨骼肌合成代谢受阻,与睾酮的减少没有关系。

白屈菜红碱对肝纤维化大鼠肝脏TGF-β1和α-SMA表达的影响

目的:探讨白屈菜红碱对四氯化碳诱导肝纤维化大鼠肝脏组织转化生长因β1(TGF-β1)和α-平滑肌肌动蛋白(α-SMA)表达的影响.方法:用四氯化碳皮下注射,同时联合营养控制和饮用100mL/L乙醇复合法制备SD大鼠肝纤维化模型,在实验第4周末,肝纤维化模型建立(2期肝纤维化形成),然后用低、中、高剂量白屈菜红碱(0.2、0.6、2.0g/L)治疗,同时实验设立病理模型组、空白对照和阳性对照(INF-γ)组.给药8wk后,采用免疫组织化学检测各组大鼠肝脏组织TGF-β1和α-SMA的表达.结果:各剂量白屈菜红碱组肝脏TGF-β1和α-SMA表达明显低于病理模型组(TGF-β1:6.08±2.35,4.31±2.10,4.7±1.70 vs 9.33±3.08;α-SMA:3.75±1.76,3.23±1.42,3.20±1.17 vs 6.67±2.29,均P<0.01),而与INF-γ组比较无明显差异(4.23±2.24,3.38±1.39,均P>0.05).结论:白屈菜红碱能降低四氯化碳诱导的肝纤维化大鼠模型肝脏组织TGF-β1和α-SMA.

哮喘大鼠肺组织CD_(44)和α-平滑肌肌动蛋白mRNA的表达

目的探讨不同时段哮喘大鼠肺组织CD44和α-平滑肌肌动蛋白(α-SMA)mRNA的表达,了解其在哮喘发病中的作用机制。方法以卵蛋白致敏制备大鼠哮喘模型.分别在激发后1、2周取肺组织.RT-PCR检测肺组织CD44与α-SMAmRNA的表达,收集肺泡灌洗液(BALF)行细胞分类计数.肺组织石蜡切片行HE染色。结果哮喘大鼠BALF中炎性细胞明显增多(P<0.05).CD44与α-SMA在正常大鼠肺组织少量表达,在激发哮喘后1周肺组织CD44与α-SMAmRNA表达均显著升高(P均<0.05).2周后升高更明显(P<0.01)。CD44和α-SMA的表达呈正相关.CD44mRNA水平与BALF中淋巴细胞和嗜酸性粒细胞的百分比呈显著正相关。结论肺组织CD44与α-SMA在转录水平的过量表达与哮喘的发生发展密切相关,二者存在相互作用.并在早期开始参与哮喘的发病。CD44与嗜酸性粒细胞、淋巴细胞向肺部炎症组织趋化浸润密切相关。

β-胡萝卜素对肝纤维化大鼠肝组织α-平滑肌肌动蛋白和转化生长因子-β_1表达的影响

目的探讨β-胡萝卜素对肝纤维化大鼠肝组织α-平滑肌肌动蛋白(α-SMA)和转化生长因子-β1(TGF-β1)表达的影响。方法将48只大鼠随机分为对照组、肝纤维化模型组和肝纤维化β-胡萝卜素干预组,SABC法免疫组织化学染色显示α-SMA及TGF-β1,HE染色显示肝的显微结构,透射电镜观察肝超微结构。结果肝纤维化模型组、对照组和β-胡萝卜素干预组α-SMA和TGF-β1表达的平均灰度值比较均有显著性差异(P<0.01)。电镜结果显示,对照组肝星形细胞内充满脂滴,其周围无明显胶原纤维沉积;肝纤维化组肝星形细胞内的脂滴较对照组减少;肝纤维化β-胡萝卜素干预组肝星形细胞内脂滴的量介于对照组与肝纤维化组之间。结论β-胡萝卜素抑制α-SMA和TGF-β1的表达,能降低由CC l4诱导的大鼠肝纤维化的程度,其作用途径与抑制肝脏星形细胞中的脂滴丢失有关。

自发性高血压大鼠阴茎组织结构和勃起功能的改变

目的:探讨自发性高血压大鼠(SHR)勃起功能的改变及其发病机制。方法:20周龄雄性SHR大鼠及同系WKY大鼠各15只,夹尾法测量大鼠收缩压(SBP),皮下注射阿朴吗啡(APO)检测阴茎勃起功能,免疫组化染色观察阴茎海绵体α-平滑肌肌动蛋白(α-SMA)及Ⅲ型胶原(COLⅢ)的表达。结果:SHR组及WKY组收缩压分别为(205.7±11.9)、(114.3±10.2)mmHg(1 mmHg=0.133 kPa),阴茎勃起次数分别为(0.6±0.5)、(2.4±0.6)次,差异均有极显著性(P<0.01)。SHR大鼠阴茎海绵体组织平滑肌及COLⅢ的表达显著高于WKY大鼠(P<0.01)。结论:高血压严重影响大鼠阴茎勃起功能,海绵体组织结构的病理改变可能是自发性高血压大鼠勃起功能下降的机制之一。

地灵丹汤对单侧输尿管梗阻大鼠模型肾间质纤维化的防治作用

目的:研究中药复方地灵丹汤对单侧输尿管梗阻(unilateral ureteral obstruction,UUO)致肾间质纤维化模型大鼠肾间质纤维化的防治作用及其可能机制。方法:将60只SD大鼠随机分为假手术组、模型组、依那普利组及地灵丹组。采用UUO法建立肾间质纤维化大鼠模型,观察血尿素氮、血清肌酐和24h尿蛋白定量及肾组织病理改变,并采用免疫组织化学法检测转化生长因子β1(transforming growth factor-β1,TGF-β1)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、纤维连接蛋白(fibronectin,FN)及层黏连蛋白(laminin,LN)的表达。结果:第7天模型组肾间质大量炎症细胞浸润及胶原表达,TGF-β1、FN和LN表达面积百分率较假手术组明显增加(P<0.05);地灵丹组间质纤维化面积较模型组减少(P<0.05)。第14天地灵丹组和依那普利组肾间质TGF-β1、α-SMA、FN和LN表达面积百分率较模型组减少(P<0.05),BUN、SCr和24h尿蛋白无明显差异。第21天地灵丹组SCr、肾间质纤维化和TGF-β1表达面积百分率较依那普利组和模型组下降(P<0.05)。结论:地灵丹能减轻单侧输尿管梗阻模型大鼠的蛋白尿和肾间质纤维化,抑制TGF-β1、α-SMA、FN和LN的表达。在较长时间应用后,地灵丹对模型大鼠的肾功能保护作用优于依那普利。