Expression and modulation of connective tissue growth factor in renal interstitial fibrosis

CTGF, a member of the CCN family of immediate early genes, is a recently discovered profibrotic growth factor, which is involved in many pathophysiologic procedures. CTGF acts as a downstream effector of TGF-β acting on interstitial cells to enhance the progression of fibrotic renal diseases. It has been shown that CTGF gene expression can be induced or blocked by some kinds of cytokine and drugs. It is an interesting candidate target for future intervention strategies of renal interstitial fibrosis.     

Impact of hydrogen sulfide donor on endothelin-1 and connective tissue growth factor expression in rats with pulmonary hypertension induced by high pulmonary blood flow

AIM: To explore the possible impact of hydrogen sulfide (H2S) donor-sodium hydrosulfide (NaHS) on endothelin-1 (ET-1) and connective tissue growth factor (CTGF) expressions in rats with pulmonary hypertension induced by high pulmonary blood flow. METHODS: Thirty-two male SD rats were randomly divided into 4 groups: shunt group, shunt+NaHS group, sham group and sham+NaHS group. Rats in shunt group and shunt+NaHS group were subjected to an abdominal aorta-inferior vena cava shunt to create an animal model of high pulmonary flow. After 11 weeks of experiment, rat systolic pulmonary artery pressure (SPAP), lung tissue H2S, plasma ET-1 concentration and lung tissue ET-1mRNA expression, as well as pulmonary artery CTGF protein expression were detected.RESULTS: After 11 weeks of experiment, SPAP, lung tissue ET-1mRNA, plasma ET-1 as well as pulmonary artery CTGF expressions were increased markedly, respectively, whereas H2S in lung tissue decreased significantly in rats of shunt group as compared with that in sham group (all P<0.05). After administration of NaHS for 11 weeks, H2S in lung tissue increased significantly, whereas SPAP, plasma ET-1 and lung tissue ET-1 mRNA expression as well as pulmonary artery CTGF protein expression decreased significantly, respectively, in rats of shunt+NaHS group as compared with that in shunt group (all P<0.05).CONCLUSION: NaHS might be involved in the development of pulmonary hypertension induced by high pulmonary blood flow by down-regulating vasoactive peptides ET-1 and CTGF expressions in lung tissues of rats.     

Effect of Ginkgo biloba extract on retinopathy in diabetic rats

AIM: To investigate the effect of Ginkgo biloba extract(GBE) on diabetic retinopathy(DR) and its possible mechanism in rats. METHODS: Goto-Kakizaki(GK) rats were used as a DR model, and were treated with different doses of GBE. Normal Wistar rats were used as the control. Blood glucose and retina barrier injury were analyzed, respectively. Ganglion cell apoptosis was detected by TUNEL staining. Moreover, the protein expression of nuclear factor E2-related factor 2(Nrf2), ERK, Bcl-2 and P53, and ERK phosphorylation were examined by Western blot.RESULTS: GBE reduced blood glucose in the DR rats, attenuated retina barrier injury, and decreased the apoptosis of ganglion cells. Furthermore, the expression of Nrf2 and Bcl-2, and phosphorylation of ERK were increased after GBE treatment, whereas P53 expression was decreased. CONCLUSION: GBE protects ganglion cells against apoptosis in DR rats, which may be through activation of Nrf2/ERK pathway and regulating Bcl-2 and P53 expression.     

Role of connective tissue growth factor in airway remodeled in rats induced by repeated bacterial infection

AIM: To investigate the role of connective tissue growth factor (CTGF) in airway remodeling in rats induced by repeating Pseudomonas aeruginosa (PA) infection. METHODS: The rats were intratracheally injected with PA for 12 times to induce chronic lung inflammation. The pathological changes of the trachea and lungs were observed, and the thickness of the trachea wall and vessel wall was measured. At the same time, the methods of immunochemistry and real-time quantitative RT-PCR were used to determine the protein and mRNA expression of CTGF in the lung tissues. The relevance between pathological changes and CTGF expression was also analyzed. RESULTS: From the 4th week, the thickness of the trachea wall and vessel wall in infectious group was larger than that in NS group (P<0.05). At the 16th week, obvious chronic inflammation in all grade bronchi appeared, the trachea walls were thickened and the lumens were narrowed in the infected animals. The expression of CTGF was significantly up-regulated (P<0.01) with positive correlations to the thickness of the trachea wall and vessel wall (r=0.880, r=0.829,P<0.01). CONCLUSION: Airway remodeling in rats is induced by repeated injection of PA. CTGF may play some roles in the pathogenesis of airway remodeling.     

Protective effect of Ginkgo biloba extract on testicular tissue of diabetic rats

AIM: To investigate the protective effect of Ginkgo biloba extract (GBE) on diabetic testis and explore its possible mechanism. METHODS: Testicular structure of streptozotocin-induced diabetic rats was observed under light microscopy (LM) and transmission electron microscopy (TEM). Content of malondialdehyde (MDA), NO₂^-/NO₃^- and activity of superoxide dismutase (SOD), nitric oxide synthase (NOS) were determined in testicular homogenate. RESULTS: In diabetic rats, it was manifestated as deformation of seminiferous tubule, atrophy and shedding of germinal epithelium under LM, while expansion of smooth endoplasmic reticulum, formation of fatty vacuoles and decrease of lysosome obviously in the cytoplasm of sertoli cell under TEM, the injury of testicular tissue was improved by GBE. Compared with diabetic rats, activity of SOD increased while activity of tNOS and iNOS, content of MDA and NO₂^-/NO₃^- decreased in GBE-treated rats. CONCLUSION: GBE could effectively prevent the development of diabetic testis and the effect may be partly achieved by resisting lipid peroxidation,restraining the activity of testicular tissue iNOS and reducing the pathological alterations of NO.     

Protective effects of extract of Ginkgo biloba on diaphragm of diabetic rats

AIM: To investigate the effects of extract of Ginkgo biloba (EGb) on diaphragm from diabetic rats. METHODS: Sprague-Dauley rats were divided into three groups: normal control, diabetic group and EGb treatment group. The morphologic changes of diaphragm tissues were studied by light and electron microscopy, the activities of succinate dehydrogenase (SDH), superoxide dismutase (SOD), nitric oxide synthase (NOS) and contents of malondialdehyde (MDA), nitric oxide (NO₂^-/NO₃-) in the diaphragm mitochondria were assayed by spectophotometer, respectively. RESULTS: The activities of SOD, SDH decreased in diabetic diaphragm mitochondria, but the activitiy of NOS, the contents of NO₂^-/NO₃^-, MDA increased compared with control group. The activities of SOD, SDH were increased as well as NOS were decreased and the contents of NO₂^-/NO₃^-, MDA decreased in EGb treatment group compared with the diabetic group. CONCLUSION: EGb may protects the diaphragm mitochondria of diabetic rats by enhancing the function of respiratory chain, anti-oxidation and decreasing NO level.     

Role of connective tissue growth factor in high glucose-induced epithelial-mesenchymal transition in podocytes

AIM: To investigate the role of connective tissue growth factor (CTGF) in high glucose-induced epithelial-mesenchymal transition (EMT) in podocytes. METHODS: The differentiated podocytes cultured under different conditions for 24 h at 37 ℃ were divided into 4 groups: control (5 mmol/L glucose solution), 5 mmol/L glucose solution supplemented with 50 μg/L CTGF, high glucose (30 mmol/L glucose solution) and high glucose supplemented with CTGF (50 μg/L). The morphology of cultured podocytes was observed under phase-contrast microscope. To study the relevant markers of EMT, the mRNA and protein expression was analyzed by real-time RT-PCR and Western blotting, respectively. In addition, the effect of CTGF inhibition with anti-CTGF antibody on high glucose-induced EMT in podocytes was investigated. RESULTS: High glucose induced phenotypic transition in the podocytes from an arborization morphology to a cobblestone morphology. After addition of CTGF to high glucose culture, the podocytes developed a feature of spindle. Under high glucose condition, podocytes underwent EMT, as the epithelial marker (nephrin) was decreased and the mesenchymal marker (desmin) was increased. Exogenous CTGF showed the effect of synergy on high glucose-induced EMT. Moreover, high glucose-induced EMT in podocytes was prevented by CTGF inhibition with anti-CTGF antibody. CONCLUSION: CTGF is involved in high glucose-induced EMT in podocytes. Inhibition of CTGF might prevent podocytes from injury in diabetes.     

Effects of Ginkgo biloba extract on myocardial TGF-β1 and collagen expression and interstitial fibrosis in type I diabetic cardiomyopathy rats

AIM:To study the effects of Ginkgo biloba extract (EGB) on myocardial TGF-β1 and collagen expression and interstitial fibrosis in type I diabetic cardiomyopathy rats. METHODS:Thirty male SD rats were randomly divided into normal control group (CON), diabetes mellitus group (DM) and EGB treatment group (EGB). Streptozocin was intraperitoneally injected into the animals in the latter 2 groups to induce type I diabetic rat model. The rats in EGB group were intraperitoneally injected with EGB. At the end of the 12th week, the body weight of each rat and its left ventri-cular weight, blood glucose, glycosylated hemoglobin and serum insulin concentration were measured. The left ventricular end-diastolic volume (LVEDV), the left ventricular end-systolic volume (LVESV), the left ventricular ejection fraction (LVEF) and the stroke volume (SV) were determined by echocardiography. The content of collagen in left ventricular myocardium, and the expression of transforming growth factor β1 (TGF-β1), procollagen type I and collagen type III were assayed by Sirius red staining, immunohistochemical staining and RT-PCR, respectively. Left ventricular myocardial cells of the neonatal SD rats were isolated and cultured in vitro with low-glucose culture medium (LG group), high-glucose culture medium (HG group) or high-glucose culture medium plus EGB (HG+EGB group). The mRNA levels of TGF-β1, procollagen type I and collagen type III were detected by RT-PCR. RESULTS:Compared with CON group, blood glucose, glycosylated hemoglobin, left ventricular weight index, the content of collagen, and the expression of TGF-β1, procollagen type I and collagen type III in left ventricular myocardial tissues of DM group were significantly increased, while the levels of blood insulin, LVEDV and SV were significantly decreased. However, compared with DM group, blood glucose, glycosylated hemoglobin, left ventricule weight index, the content of collagen, and the expression levels of TGF-β1, procollagen type I and collagen type III in the left ventricular myocardial tissues of EGB-treated rats were significantly decreased, while the levels of blood insulin, LVEDV and SV were significantly increased. Compared with LG group, the mRNA expression levels of TGF-β1, procollagen type I and collagen type III were significantly increased. However, compared with HG group, the mRNA expression levels of TGF-β1, procollagen type I and collagen type III were significantly decreased after treated with EGB. CONCLUSION: EGB retards the process of myocardial fibrosis and improves the cardiac functions in type I diabetic cardiomyopathy rats by down-regulating the expression of TGF-β1, reducing the synthesis and deposition of collagen type I and collagen type III.     

银杏摘心处理对枝梢和叶片生长的影响

为探讨银杏夏季摘心对枝叶生长发育的影响,2005年在广西植物研究所银杏良种园内对银杏高接换种树1年生枝梢进行了夏季摘心试验。采用Li-3000A叶面积仪定期测量嫩叶面积;同时在摘心前后对一次梢和二次梢的粗度、长度进行测定,统计二次梢的萌发数量。结果表明,夏季摘心有效地抑制了枝条的加长生长,促进了加粗生长,摘心后一次枝粗是对照的1.52倍;并促进二次枝的萌发和有效叶片数的增加,摘心后枝条上平均每芽着生的叶片数是对照的3.50倍;摘心还促进了叶面积的快速增长,提早叶片成熟时间,有利于光合产物的合成,为提早结果、提高果实产量和品质奠定基础。另外,叶面积与叶柄长和粗之间均呈极显著线性正相关。该项研究将为银杏夏季整形修剪提供理论和实践依据。     

Effect of Ginkgo biloba extract on cerebral ischemia during early stage of subarachnoid hemorrhage in rats

AIM: To investigate the effect of Ginkgo biloba extrac (GBE) on cerebral ischemia during early stage of subarachnoid hemorrhage (SAH). METHODS: Noncraniotomy models of SAH in Wistar rats were used and animals were divided into sham-operated group, SAH group and SAH+GBE group. Dynamic change of regional cerebral blood flow (rCBF) was detected. Brain endothelin-1(ET-1) and calcium contents were also determined at different time point during 24 hours after the operation. Pathological change of neurons of hippocampus CA1 region was observed. RESULTS: In SAH group, rCBF decreased immediately and persistently after induction of SAH. Values of brain ET-1 content and calcium content at 1 hour, 6 hours and 24 hours were significantly higher than those in sham-operated group. Neurons of hippocampus CA1 region were damaged severely 3 days after onset of SAH. Above abnormal changes in SAH+GBE group were much slighter than those in SAH group. CONCLUSION: GBE may relieve cerebral ischemic damage after SAH.     

Up-regulation of miR-133a expression attenuates myocardial fibrosis in spontaneously hypertensive rats

AIM: To investigate the effect of up-regulated expression of microRNA-133a (miR-133a) on myocardial fibrosis in spontaneously hypertensive rats (SHR). METHODS: Wistar-Kyoto (WKY) rats with homologous normal blood pressure served as the normal control group. SHR were divided into SHR group, SHR+ adeno-associated virus (AAV) group and SHR+miR-133a-AAV group randomly. miR-133a carried by miR-133a-AAV was transfected into SHR heart by coronary perfusion. The rat tail artery pressure was monitored. The myocardial collagen deposition was observed by Masson staining. The expression of miR-133a in myocardial tissue was detected by real-time PCR. The protein levels of transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) were determined by immunohistochemistry and Western blot. RESULTS: Compared with the WKY rats, the tail artery pressure of the SHR increased significantly. The expression of miR-133a in heart decreased, and the expression levels of TGF-β1 and CTGF increased (P<0.05), and myocardial fibrosis occurred. After up-regulating the expression level of miR-133a in the heart of SHR, the myocardial fibrosis was significantly reduced, and the expression levels of TGF-β1 and CTGF decreased (P<0.05). CONCLUSION: Up-regulation of the miR-133a expression improves myocardial fibrosis induced by hypertension, which may be related to inhibiting the protein expression of TGF-β1 and CTGF in myocardium.     

The kinetic alteration of nitric oxide formation in the lungs in the development of pulmonary fibrosis of rats

AIM: To observe the kinetic alteration of nitric oxide formation in the lungs in the development of pulmonary fibrosis in the rat. METHODS: The contents of hydroxyproline in the lungs, NO₂^-/NO₃^- (nitrite/nitrate) in out-flowing and in-flowing pulmonary blood (OPB, IPB) were assayed on the day 7, 14, 21, 30 and 70 after intratracheal administration of bleomycin A₅ . The content of NO₂^-/NO₃^- in supernatants of culture of the alveolar macrophages (AMs) and the amount of iNOS positive stain cells in lung tissue section were also observed in the rat on 14th day after-bleomycin A₅ administration. RESULTS: The content of lung hydroxyproline had no change on the 7th day, increased on the 14th day (P＜0.05), increased significantly on the 21th day, 30th day and 70th day post-bleomycin A₅ compared with control rats. On the 7th day and 14th day, the content of NO^- ₂ /NO₃^- increased in OPB and decreased in IPB (P＜0.01). On the 21th day, the content of NO₂^-/NO₃^- abated in OPB (P＞0.05) but still decreased in IPB (P＜0.01). On the 30th day and the 70th day, the NO₂^-/NO₃^- level recovered both in OPB and IPB. AMs from rats on the 14th day post-bleomycin A₅ showed significant elevation (P＜0.01) in NO₂^-/NO₃^- level. The amount of iNOS positive stain cells increased in rats on the 14th day post-bleomycin A₅. CONCLUSION: The amount of NO in the lungs was high in the initial phase of fibroproliferative reaction induced by bleomycin A₅ ,and these might be associated with the enhanced ability of AMs to release NO and the increased amount of iNOS.     

Effects of uremic serum of different molecular weight groups ongene and protein expression of connective tissue growth factor gene and proteinexpression in human renal tubular epithelial cells

AIM:To investigate the effects of uremic serum of different molecular weight groups on gene and protein expression of connective tissue growth factor (CTGF) in human renal tubular epithelial cells.METHODS:The serum from 40 chronic renal failure patients and 20 healthy volunteers were collected and uremic serum was segregated to three groups: >10 000 D,5 000-10 000 D,<5 000 D by 10 000 D and 5 000 D molecular weight Centricon Plus 20 Centrifugal Filter Devices.The protein expression of CTGF was examined by Western blotting.The mRNA expression of CTGF was detected by RT-PCR.RESULTS:CTGF gene expression were increased in 2.5%-20% uremic serum groups compared with that in normal control group,and it was the highest in 10% uremic serum groups.CTGF gene expression was increased significantly in molecular weight >10 000 D and 5 000-10 000 D groups,and the highest was in >10 000 D group,but it was no significant difference in <5 000 D group compared with that in normal control group.CTGF protein was increased in different molecular weight uremic serum groups compared with that in normal control group,and gradually increased following the increasing of uremic serum concentration and it was the highest in molecular weight >10 000 D group.CONCLUSION:Human renal tubulointerstitial fibrosis was accelerated significantly by uremic toxin,especially molecular weight >10 000 D uremic toxin through promoting the gene and protein expression of CTGF in renal tubular epithelial cells in patients with chronic renal failure.     

Effect of gingko biloba extract on liver from experimental type 2 diabetic rats

AIM:To study the protective effect of the ginkgo biloba (EGB) extract on liver from experimental type 2 diabetic rats and to explore its possible mechanism. METHODS:Thirty-nine male Sprague-Dawley rats were divided randomly into four groups: normal control group, high-fat group, diabetic group and EGB-treated group. After fed with high-fat diet for 4 weeks, the later two groups were injected with streptozotocin intraperitoneally to induce type 2 diabetes mellitus. EGB-treated group was injected intraperitoneally with EGB at a dose of 8 mg·kg^-1·d^-1, and the other three groups were treated with normal saline of the same volume. After 8 weeks, the morphologic change of hepatic tissue was observed under transmission electron microscope (TEM) and light microscope (LM), respectively. In addition, the activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX), total nitric oxide synthase (TNOS), inducable nitric oxide synthase (iNOS) and the content of malondialdehyde (MDA), nitric oxide (NO) in liver homogenate were detected biochemically. RESULTS:Obvious liver fatty degeneration, apparent decrease of glycogen granules in cytoplasm of hepatocytes under light microscope and hepatocytes pyknosis, lots of lipid deposits in cytoplasm of hepatocytes, proliferation of hepatic stellate cells and collagen under TEM were observed in diabetic group. The activity of SOD, CAT, GSH-PX decreased but the activity of tNOS, iNOS and the content of MDA, NO^-₂/NO^-₃ increased in diabetic group compared with normal control group. The pathological change was relieved in EGB-treated group. The activity of SOD, CAT, GSH-PX increased, the activity of tNOS, iNOS and the content of MDA, NO^-₂/NO^-₃ decreased in the liver of rats in EGB-treated group compared with diabetic group. CONCLUSION:EGB exerts a beneficial effect on liver in experimental type 2 diabetic rats. Anti-lipid peroxidation and suppression of NO production may be involved in this process.     

不同干燥方式对银杏粉品质的影响

为了研究银杏果高值化加工技术,实现银杏产业提质增效,分别采用普通热风干燥、喷雾干燥、冷冻干燥和微波-热风组合干燥四种干燥方式对银杏进行干燥处理,将银杏脱毒后加工成银杏粉,然后对银杏粉的品质进行了比较分析。试验结果表明,不同干燥方式对银杏粉的品质有较大的影响,其中冷冻干燥对粉体色泽保持最好;喷雾干燥粉体的平均粒度最小,粒径分布最均匀,比表面积最大,溶解性指数最大;热风干燥银杏粉堆密度最大、休止角最小,流动性最好,溶解时间最短。     

银杏苗根生垂乳分泌腔的解剖结构与组织化学研究

以银杏苗木根生垂乳为试材,通过树脂半薄切片技术观察分泌腔的发生发育过程,运用组织化学方法初步研究分泌腔分泌物的主要成分。结果表明：银杏苗根生垂乳中,分泌腔主要分布在皮层中,由一层分泌细胞围绕一个圆形或椭圆形的腔道和2 ~ 3层鞘细胞构成,分泌腔直径平均为566.7 μm。分泌腔由原始细胞团细胞裂溶生而形成,原始细胞团细胞较小,细胞核大,细胞质浓。随分泌腔发育,原始细胞团中央细胞胞间层膨胀、溶解,形成胞间隙,胞间隙扩大到一定程度,中央细胞开始溶解。分泌腔随中央细胞不断溶解而扩大直至分泌细胞停止溶解,分泌腔成熟。根生垂乳顶端皮层及不定芽分生组织中有大量发育程度不同的分泌腔。根生垂乳原始细胞团具有较强的嗜锇性,核蛋白丰富,但淀粉粒较少。中央细胞溶解阶段,分泌细胞及空腔中均有嗜锇物质,空腔中还有大量蛋白质类物质及少量较小的淀粉粒。分泌腔成熟后,分泌腔中基本无蛋白质及淀粉粒,但分泌细胞与鞘细胞均呈现较强的嗜锇性。     

银杏种实生长发育过程中胚乳淀粉体发育观察

对银杏胚乳发育过程进行连续2年的观察结果表明:1)发育成熟的银杏胚乳包括糊粉层与内胚乳2个部分,淀粉体主要积累在内胚乳细胞中,均为单粒淀粉,发育成熟的淀粉体可分为大粒和小粒2种;2)根据淀粉体的形状、大小和发育程度大致可分为淀粉体发生期、淀粉体体积与数量快速增长期、淀粉体发育成熟期3个时期;3)胚乳淀粉体的发生时期及充实部位表现出很大差异,合点端胚乳细胞中的淀粉体发生早,充实快,而珠孔端胚乳细胞中的淀粉体发生迟,充实速度慢;内胚乳外围细胞中淀粉体的充实要高于内部;颈卵器周围的胚乳细胞淀粉体的充实差。