Effect of ligustrazine on pulmonary arterial pressure and pulmonary arterial wall collagen of chronic hypoxic hypercapnic rats

AIM:To study the effect of ligustrazine on pulmonary hypertensive rats induced by hypoxic hypercapnia. METHODS:Thirty rats were randomly divided into three groups:control group(A),hypoxic hypercapnic group(B), hypoxic hypercapnia+ligustrazine(lig.) group(C). RESULTS: (1) Mean pulmonary arterial pressure(mPAP)of group B was significantly higher than that of group A and mPAP of group C was significantly lower than that of group B(P＜0.01),differences of mean carotid pressure(mCAP) were not significant among three groups (P＞0.05); (2)Electron microscopy and immunohistochemistry showed ligustrazine could inhibit the diposition of collagenous fiber(collagen typeⅠ)in pulmonary arterioles induced by hypoxic hypercapnia; (3) Plasma endothelin level of group C was significantly lower than that of group B (P＜0.01), serum (NO ₂^-/NO₃^-) of group C was significantly higher than that of group B (P＜0.01). CONCLUSION:Ligustrazine can inhibit pulmonary hypertension and the diposition of collagen type Ⅰ in pulmonary arterial wall induced by hypoxic hypercapnia.     

Effects of bone mesenchymal stem cell transplantation on silicosis fibrosis in rats

AIM: To study the effects of exogenous bone mesenchymal stem cell (BMSC) transplantation on silicosis fibrosis in rats, and to explore the dose-effect relationship. METHODS: BMSCs were isolated and cultured from male 5-week-old SD rats in vitro. Fifty healthy female SD rats were randomly divided into 5 groups: control group, silicosis model group, BMSCs treatment A group (1×10⁹ cells/L), BMSCs treatment B group (3×10⁹ cells/L) and BMSCs treatment C group (5×10⁹ cells/L). The silicosis model was made by one-time infusion of silica dust suspension using the non-exposed tracheal intubation, and different doses of BMSCs were given for intervention therapy. All the rats were sacrificed on the 21st day after the model was established. The morphological changes of the lung tissues were observed by HE staining and Masson staining. The localization and distribution of tumor necrosis factor α (TNF-α) and transforming growth factor β (TGF-β) were determined by the method of immunohistochemistry. The protein levels of TNF-α, TGF-β, collagen type I and collagen type III were detected by Western blotting. The sex-determining region (SRY) protein was searched by an immunofluorescence method to confirm the homing of BMSCs. RESULTS: Compared with control group, the silicosis model group had significant alveolitis changes, silicon nodule formation, collagen deposition and other pathological characteristics. Compared with silicosis model group, the pathological changes in BMSCs treatment A group were improved. The conditions of BMSCs treatment B group were also improved significantly. However,the pathological changes in BMSCs treatment C group were increased obviously. The protein levels of TNF-α, TGF-β, collagen type I and collagen type III in the lung tissues ranked as follows: BMSCs treatment C group > silicosis model group > BMSCs treatment A group > BMSCs treatment B group > control group. The difference between BMSCs treatment C group and silicosis model group was not statistically significant, and the differences between the other groups were statistically significant. The SRY-positive cells were observed in BMSCs treatment B group, but no significant expression in the heart, liver, spleen and kidney tissues was observed. CONCLUSION: The exogenous BMSC transplantation antagonizes the development of silicosis fibrosis in rats, which has dose-effect relationship.     

Effect of Different Flavonoids on Collagen Synthesis in Human Fibroblasts

In this study, we discovered that flavonoids belonging to the subclasses: (flavanone, flavone, and flavonol) display differential effects on the synthesis of collagen in human dermal fibroblasts. At 80 μg/ml flavonoids quercetin-3,3′,4′, 5,7-pentahydroxyflavone, 3-methyl quercetin, and 7-hydroxyflavone significantly decreased the total protein concentration which was a direct consequence of their cytotoxic effect, while naringenin exhibited no effect on total collagen and total protein concentration. Quercetin-3,3′4′,7-tetramethyl ether, 4′-hydroxyflavanone, flavanone, and fisetin significantly decreased collagen concentration while morin, rutin, and chrysin increased collagen concentration without changing the overall protein concentration. The initial screening performed in this study enables the identification of compounds that exert significant effects on fibroblast function and show potential as starting material for pharmaceutical preparations targeted against various disorders centered around disturbed collagen metabolism.     

Role of caveolae in high glucose-induced extracellular matrix production in rat mesangial cells

AIM：To investigate the role of caveolae in high glucose (HG)-induced extracellular matrix (ECM) production in rat mesangial cells (MCs). METHODS：Synchronized rat MCs were divided into normal glucose group, HG group, HG+methyl-β-cyclodextrin (β-MCD) group and HG+β-MCD+cholesterol (Chol) group. Western blotting was used to detect the protein expression of caveolin-1 (Cav-1), phosphorylated caveolin-1 (p-Cav-1-Y14) and collagen type 1 (Col I). The mRNA expression of Cav-1 was determined by real-time PCR. ELISA was used to measure the level of fibronectin (FN) in the supernatant. RESULTS：High glucose significantly increased the expression of FN and Col I. In HG 12, 24 and 48 h groups, the mRNA and protein levels of Cav-1 were not significantly different from those in HG 0 h group, whereas the level of p-Cav-1-Y14 was significantly increased. β-MCD significantly attenuated HG-induced elevation of p-Cav-1-Y14 and FN production, but had no effect on HG-induced Col I expression. All these responses to β-MCD were abolished by Chol. CONCLUSION：High glucose significantly increases the production of Col I and FN in rat MCs. FN production induced by high glucose is mediated by p-Cav-1-Y14.     

Effect of different mechanical isolation techniques on developmental competence and survival of buffalo ovarian preantral follicles

The present study aimed to analyze different methods of mechanical isolation of buffalo preantral follicles (Experiment I), in vitro culture of isolated follicles in different groups of culture medium over collagen gel matrix (Experiment II) and subsequent in vitro development and survival of isolated preantral follicles (PFs) (Experiment III). In Experiment I, ovarian cortical pieces were separated and PFs isolated by different mechanical methods. In Experiment II, isolated follicles were divided into three groups and cultured in TCM-199 having 10% FBS, 1% ITS, and 20 ng/ml EGF (Group A, control), addition of 0.5 μg/ml FSH (Group B) or FSH + 100 ng/ml IGF-I (Group C). Follicles were incubated at 38.5 °C in 5% CO₂ with maximum humidity. In Experiment III, based on the outcome of Experiment I and II, PFs were cultured from those isolation method and treatment group, showing better growth and developmental pattern to analyze the impact of growth factors on in vitro growth of follicles in long term culture. It was found that micro-dissected PFs showed higher survival rate and growth after 15 days of culture compared to PFs isolated by other methods. Follicles cultured with FSH + IGF-1 on collagen gel matrix, showed significantly (P < 0.05) higher survival rate and mean diameter of follicles on day 15 of culture compared to control. In summary, it has been shown that isolation of follicles by micro-dissection has advantages over other methods, being relatively simple, inexpensive and less harmful to follicles. Micro-dissected buffalo PFs maintained the architecture, showed antrum formation in presence of FSH and IGF-I over the collagen gel matrix.     

Inhibitory effect of sorafenib on collagen synthesis in human hepatic stellate cells

AIM: To investigate the effects of sorafenib on collagen synthesis in human hepatic stellate cells (HSCs). METHODS: HSC cell line LX-2 was used in vitro in this study. -proline incorporation assay was performed to measure the collagen synthesis. Immunocytochemistry was applied to detect type I collagen and real-time PCR was used to determine the mRNA expression of collagen α1 (I). RESULTS: Stimulation with platelet-derived growth factor (PDGF) induced the increase in type I collagen synthesis, while treatment with sorafenib (10.0 μmol/L) for 24 h markedly decreased the collagen synthesis. Sorafenib resulted in dose-dependent and time-dependent decrease in collagen synthesis in LX-2 cells in the absence or presence of PDGF by -proline incorporation assay. The inhibition rates were 22.69%, 37.52% and 71.74%, respectively, when LX-2 cells was treated with sorafenib at 10.0 μmol/L for 12 h, 24 h and 48 h. Sorafenib dose-dependently blocked the mRNA expression of collagen α1 (I) in LX-2 cells stimulated with PDGF. Sorafenib at the concentrations of 2.5 μmol/L, 5.0 μmol/L and 10.0 μmol/L down-regulated the mRNA expression of collagen α1 (I) in LX-2 cells by 58.66%, 67.06% and 81.64%, respectively. CONCLUSION: Sorafenib inhibits the collagen synthesis and blocks the expression of type I collagen at mRNA and protein levels in vitro in LX-2 cells. Therefore, sorafenib may be a potential therapeutic agent in the treatment of liver fibrosis.     

武昌鱼鱼鳞胶原蛋白提取工艺的研究

[目的]探索武昌鱼鱼鳞胶原蛋白的最佳提取工艺条件。[方法]以武昌鱼鱼鳞作为原料,采用不同浓度的盐酸作为脱钙溶液,用0.5 mol/L乙酸-乙酸钠缓冲溶液提取其胶原蛋白。以胶原蛋白提取率为指标,选择脱钙时间、脱钙酸浓度、固液比和提取时间4个因素为影响因子,通过正交试验确定武昌鱼鱼鳞胶原蛋白的最佳提取工艺条件。[结果]正交试验表明,当提取温度确定为12℃时,4个因素对武昌鱼鱼鳞胶原蛋白提取率的影响程度依次为提取固液比﹥脱钙时间﹥脱钙酸浓度﹥提取时间。提取鱼鳞胶原蛋白的最佳工艺条件为:固液比1∶25,脱钙时间3 h,提取时间每次1.5 d,脱钙酸浓度为0.4 mol/L,在此条件下,胶原蛋白提取率为1.142%。[结论]该研究为鱼鳞胶原蛋白的开发和应用提供参考依据。     

鸡肉嫩度评定方法及其指标间的相关分析

采用剪切值、胶原蛋白(总胶原蛋白、热溶性胶原蛋白、热残留胶原蛋白)和肌纤维结构(肌纤维密度、肌纤维直径)3种方法,分别评定了7个不同鸡种的嫩度。结果表明,应用3种评定方法可以划分出鸡种间的嫩度等级,但各指标间的嫩度排序有差异。相关分析表明,剪切值、总胶原蛋白、热残留胶原蛋白和肌纤维直径是嫩度评定的主要指标。其中剪切值与热残留胶原蛋白、热残留胶原蛋白与肌纤维直径和总胶原蛋白与热残留胶原蛋白为极显著正相关(P<0 01),剪切值与肌纤维直径为显著正相关(P<0 05)。经综合分析,剪切值的分辨率最高,热残留胶原蛋白、肌纤维直径综合代表性较强。以上评定结果与感官评定的嫩度对比有一定差异,感官评定与组织结构评定的结果相近,与剪切值、胶原蛋白两种方法差异较大。胸腿肌的嫩度不同方法存在差异,鸡种间比较建议采用胸肌为代表进行嫩度比较。     

Inhibitory effects of propolis on platelet adhesion in flowing blood in vitro

AIM:To investigate effects of propolis-ethanol extract on platelet activity in flowing blood. METHODS:Intima-injury model was made by in vitro perfusion. Coverslips was coated by using fibrinogen and human Ⅲ type collagen to detect platelet adhesive rate when blood went through fibrinogen and collagen surface in 1 000/s shear rate. Three experimental groups were set up: negative control group (24% ethanol), experimental group (0.1 g/L, 24% propolis-ethanol extract) and positive control group (0.1 g/L, ferulic acid). RESULTS:Intima-injury model was made. On fibrinogen and collagen, platelet adhesion on area of experimental group was lower than that in negative control group (P<0.01). There was no significant difference between experimental group and positive control group (P>0.05). Propolis-ethanol extract decreased more obviously the platelet adhesion area on fibrinogen surface than that in collagen surface (P<0.01). CONCLUSION:Propolis-ethanol extract inhibits platelet activation and reduces its adhesion on fibrinogen and collagen surface, especially in fibrinogen surface.