Simultaneous transfer of vascular endothelial growth factor and hepatocyte growth factor genes effectively promotes liver regeneration after hepatectomy in cirrhotic rats

BACKGROUND/AIMS: Liver regeneration in a cirrhotic liver is unsatisfactory. In the course of liver regeneration, non-parenchymal cells such as sinusoidal endothelial cells as well as hepatocytes increase in number while the liver structure and physiological functions are maintained. The aim of this study was to examine whether sufficient liver regeneration could be obtained by the simultaneous, preoperative injection of recombinant adenoviral vectors encoding human vascular endothelial growth factor (VEGF), a potent mitogen for sinusoidal endothelial cells, (pAxCAVEGF) and rat hepatocyte growth factor (HGF), a potent mitogen for hepatocytes, (pAxCAHGF) in 70% hepatectomized cirrhotic rats. METHODOLOGY: Forty-eight hours before 70% hepatectomy, dimethylnitrosamine-induced cirrhotic rats were infused intravenously with pAxCAVEGF or with pAxCAVEGF and pAxCAHGF, or with a control virus encoding Escherichia coli beta-galactosidase (pAxCALacZ). RESULTS: Strong VEGF mRNA expressions were shown in the livers of VEGF and VEGF/HGF-treated animals. The plasma HGF concentrations in the VEGF/HGF-treated rats were elevated compared with the other groups. Proliferating cell nuclear antigen immunostaining showed increased labeling indices of hepatocytes in the VEGF/HGF-treated rats at 24 and 48 h after hepatectomy. PCNA labeling indices of SECs were increased in the VEGF and VEGF/HGF-treated rats compared with the control animals at 24 and 48 h after hepatectomy. Moreover, the hepatic regeneration rate after hepatectomy was significantly augmented by the VEGF and VEGF/HGF treatment. CONCLUSIONS: Simultaneous preoperative injection of recombinant adenoviral vectors encoding VEGF and HGF effectively stimulates liver regeneration in cirrhotic rats.     

Hepatocyte growth factor as well as vascular endothelial growth factor gene induction effectively promotes liver regeneration after hepatectomy in Solt-Farber rats

BACKGROUND/AIMS: Hepatic oval cells play an important role in liver regeneration when proliferation of mature hepatocytes is inhibited. The aim of this study was to examine the effect of hepatocyte growth factor (HGF), or vascular endothelial growth factor (VEGF) on proliferation of oval cells in the Solt-Farber rat model. METHODOLOGY: One hour after 70% partial hepatectomy, 2-acetyl-aminofluorene-induced damaged rats were infected intravenously with recombinant adenoviral vectors, encoding rat HGF or human VEGF, or Escherichia coli beta-galactosidase as a control. RESULTS: The plasma HGF concentrations in the HGF-transferred rats were elevated compared with the other groups at 4 and 7 days after hepatectomy. Oval cells were confirmed by positive staining of both cytokeratin-19 and alpha-fetoprotein. Oval cells around the portal tracts in the HGF or VEGF-transferred rats increased in number compared with the control rats at 7 and 9 days after hepatectomy. The proliferating cell nuclear antigen labeling indices of oval cells and the hepatic regeneration rate after hepatectomy were significantly augmented by the HGF or VEGF treatment. Moreover, cyclin E expression was elevated in the HGF-treated rats. CONCLUSIONS: In the Solt-Farber rat model, HGF or VEGF gene injection effectively promoted liver regeneration after hepatectomy mainly with increased proliferation of hepatic oval cells.     

血管内皮生长因子及其受体在肺气肿患者肺组织中的表达

目的探讨血管内皮生长因子(VEGF)及其受体2(VEGF受体2/KDR)在肺气肿患者肺组织中的表达及其与肺气肿的相关性。方法取35例行肺叶切除术患者[A组(吸烟伴肺气肿组)16例,B组(不吸烟肺功能正常组)14例,C组(吸烟但肺功能正常组)5例]的外周肺组织标本,ELISA法检测肺组织匀浆中VEGF的含量,免疫组化法检测KDR蛋白表达,RT PCR检测VEGF和KDRmRNA水平,TUNEL法检测肺泡隔细胞的凋亡。结果A组患者肺组织VEGF、KDR表达均低于B组(P<0.01),肺泡隔细胞凋亡率高于B组(P<0.01)。C组与B组相比,VEGF及KDR表达差异无统计学意义(P>0.05)。结论VEGF及KDR水平减少与肺泡隔细胞凋亡的增加可能与肺气肿的发生相关。     

Expression of vascular endothelial growth factor and receptor flk-1 in colon cancer liver metastases

Background/Purpose

This study investigated vascular endothelial growth factor (VEGF) and flk-1 expression in hepatic metastases from colon carcinoma, and their associations with tumor angiogenesis, proliferation, and apoptosis.

Methods

Immunohistochemical studies were performed for VEGF/flk-1, Ki-67, p53, and bcl-2 expression, and microvessel density (MVD) in surgical specimens from 35 patients who underwent hepatectomy for colon cancer liver metastases between 1986 and 2001.

Results

VEGF and flk-1 were expressed mainly in the cytoplasm of tumor cells. High VEGF expression was associated with high flk-1 expression (P = 0.043). MVDs of less than 15 and 15 or more were found in 5 (14.3%) and 30 (85.7%) of 35 hepatic metastases, respectively. A Ki-67 index (KI) of 50% or more was detected in 33/35 (94.3%) of tumors, and 23 of these (65.7%) showed a KI of 85% or more. A KI of less than 50% was present in 2/35 (5.7%) of tumors. The expression of VEGF/flk-1 was related to elevated MVD (P ≤ 0.026). VEGF was also associated with an increased KI (P = 0.025). Mutant p53 and bcl-2 expressions were detected in 26/35 (74.3%) and 17/35 (48.6%) of liver metastases, respectively. Mutant p53 was not related to VEGF/flk-1 expression, but bcl-2 was highly associated with flk-1 (P = 0.007). The incidences of high flk-1 expression and a KI of 85% or more were significantly higher in tumors which were both p53- and bcl-2-positive (93.3% and 73.3%) than in tumors which were negative for both (42.9% and 14.3%; P ≤ 0.021).

Conclusions

The VEGF-flk-1 system takes part in tumor angiogenesis, proliferation, and apoptosis in colon liver metastases. The bcl-2 pathway may upregulate VEGF activity via the flk-1 receptor. These findings are preliminary, requiring a larger sampling in order to elucidate the role of VEGF/flk-1 in metastatic colon cancer.

     

VEGF反义寡核苷酸对胆囊癌细胞VEGF,Flt-1及KDRmRNA表达和VEGF蛋白分泌的影响

目的:体外研究Oligofectamine介导的VEGF反义寡核苷酸(antisense oligodeoxynucleotide,ASODN)转染对人胆囊癌GBC-SD细胞VEGF,Flt-1及KDR mRNA表达和VEGF蛋白分泌的影响.方法:运用Oligofectamine介导的VEGF反义寡核苷酸(ASODN)和错义寡核苷酸(Scrambled Oligodeoxynucleotide,SODN)转染人胆囊癌细胞GBC-SD,半定量RT-PCR检测转染后各组细胞不同时间的VEGF,Flt-1及KDR mRNA表达变化,ELISA测定转染后各组细胞培养上清液VEGF蛋白浓度.结果:半定量RT-PCR发现ASODN组及ASODN Oligofectamine组24,48,72,96 h VEGF(ASODN组VEGF165:0.686±0.033,0.569±0.049,0.489±0.036,0.716±0.017;ASODN组VEGF121:0.462±0.046,0.338±0.034,0.219±0.022,0.471±0.038;ASODN Oligofectamine组VEGF165:0.601±0.021,0.465±0.042,0.416±0.023,0.662±0.035:ASODN Oligofectamine组VEGF121:0.408±0.014,0.286±0.019,0.157±0.021,0.418±0.037)、Flt-1(ASODN组:0.694±0.019,0.562±0.045,0.435±0.042,0.724±0.026;ASODN Oligofectamine组:0.609±0.018,0.442±0.049,0.314±0.015,0.614±0.029)及KDR(ASODN组:0.667±0.063,0.490±0.033,0.301±0.029,0.665±0.068;ASODN Oligofectamine组:0.523±0.048,0.432±0.027,0.218±0.036,0.524±0.037) mRNA的表达显著低于Control组(P<0.05),且ASODN Oligofectamine的抑制作用比ASODN强(P>0.05).ELISA测定结果显示ASODN组(281.26±18.62,526.44±34.95,791.13±20.99)及ASODN Oligofectamine组(250.7±14.57,506.09±19.14,711.79±19.91)24,48,72 h VEGF蛋白的分泌浓度均显著低于Control组(394.23±16.26,711.6±26.21,933.85±28.65)(P<0.05),且ASODN Oligofectamine的抑制作用比ASODN强(P>0.05).结论:Oligofectamine介导的VEGF ASODN能抑制GBC-SD细胞VEGF,Flt-1及KDR mRNA表达和VEGF蛋白分泌.     

神经发生、血管内皮生长因子与血管性认知损害

神经发生是神经前体细胞自我增殖和分化产生新神经元的动态过程。研究证实,海马神经发生可改善认知功能,并且血管内皮生长因子(vascular endothelial growth factor, VEGF)在神经发生中发挥着重要的调控作用。文章就 VEGF 促进神经发生的机制以及神经发生改善血管性认知损害的作用进行了综述。     

Serum levels of vascular endothelial growth factor,basic fibroblast growth factor and endostatin in human metastatic liver tumors

BACKGROUND/AIMS: Angiogenic factors are related to the malignant potential of tumors. This study aimed to investigate the relationship of serum angiogenic factors to liver metastasis. METHODOLOGY: The serum levels of vascular endothelial growth factor, basic fibroblast growth factor and endostatin were measured using EIA in 25 patients with metastatic liver tumors and were compared with those of 12 cancer patients without metastasis and 15 controls. RESULTS: The serum vascular endothelial growth factor concentration was significantly higher in the liver metastasis group (503 +/- 84 pg/mL) than in the no metastasis group (205 +/- 38 pg/mL) and the control group (201 +/- 26 pg/mL). The three groups had similar serum basic fibroblast growth factor concentrations. There was no significant difference in serum levels of endostatin among the liver metastasis group (18.8 +/- 1.5 ng/mL), the no metastasis group (23.9 +/- 4.9 ng/mL), and the control group (17.1 +/- 1.5 ng/mL). CONCLUSIONS: Angiogenic response is more prominent than anti-angiogenic responses in liver metastasis. These findings support the rationale for anti-angiogenesis therapy such as endostatin therapy in patients with liver metastasis.     

嗅鞘细胞联合血管内皮生长因子促进周围神经再生的实验研究

目的探讨嗅鞘细胞(OECs)与血管内皮生长因子(VEGF)联合移植促进坐骨神经再生的协同作用。方法取SD大鼠60只,随机分成4组,即生理盐水(CON)组、VEGF组、OECs组和VEGF+OECs组。制作大鼠坐骨神经缺损模型,在再生室内分别注入CON、VEGF、OECs、VEGF+OECs。术后观察各组大鼠一般状态,并于术后4周和12周在光镜、电镜下观察再生室神经再生情况,检测大鼠坐骨神经电生理情况等。结果 VEGF组、OECs组和VEGF+OECs组坐骨神经单位横断面有髓神经纤维计数及其直径,电生理检测结果及腓肠肌湿质量均高于CON组(P均<0.05)。VEGF+OES组神经纤维的组织形态学优于VEGF、OECs组。结论 OECs移植联合VEGF对大鼠神经再生均有明显的促进作用,二者有协同作用。     

布地奈德/福莫特罗对支气管哮喘患者血管内皮生长因子及其受体1表达及气道重塑的调控作用

目的支气管哮喘(简称哮喘)是一种慢性气道炎症疾病,伴随气道高反应性、可逆性气流阻塞和气道重塑。血管生成和微血管重塑在气道慢性炎症过程中可能起到重要的作用。血管内皮生长因子(vascular endothelial growth factor,VEGF)是一种促血管生成因子,其生理作用包括促进内皮细胞存活、增殖和迁移。本研究通过检测哮喘患者气道VEGF和VEGF受体1(VEGFR1)的表达,探讨VEGF和哮喘患者气道重塑的关系以及布地奈德/福莫特罗对哮喘患者气道重塑的调控作用。方法支气管组织来源于2006年4月至11月四川大学华西医院经纤维支气管镜行组织活检。23例为中度哮喘患者,20例为对照组。哮喘患者给予规律吸入布地奈德/福莫特罗4.5/160μg,2次/d,持续半年。VEGF和VEGFR1通过免疫组织化学进行检测。AB-PAS和MassonTrichrome染色用于评估气道重塑程度。结果两组之间年龄和性别差异无统计学意义。而两组之间用力肺活量占预计值%,第一秒用力呼气容积占预计值%,PC20,V75占预计值%,V50占预计值%和V25占预计值%的差异有统计学意义。哮喘组患者气道黏液腺增生、平滑肌增厚、上皮下纤维化以及新生血管增加。与对照组比较,VEGF和VEGFR1阳染细胞数目增多,表达增加。VEGF和VEGFR1表达增加与哮喘患者的气道重塑、气流阻塞和气道高反应性呈正相关。规律吸入布地奈德/福莫特罗6个月后,哮喘患者VEGF和VEGFR1表达减少,气道重塑减轻。结论伴随哮喘患者气道血管生成增多和气道重塑,VEGF和VEGFR1表达增加。规律吸入布地奈德/福莫特罗可以通过减少VEGF和VEGFR1表达而减轻哮喘患者气道重塑。阻断VEGF和VEGFR1可能是治疗哮喘的新策略。     

骨骼肌卫星细胞移植后心肌梗死区血管内皮因子表达及血管新生作用

目的:研究骨骼肌卫星细胞移植后心肌梗死(MI)区血管内皮因子(VEGF)表达及血管新生作用。方法:成年Louis近交系大鼠,结扎前降支建立急性MI模型,将骨骼肌卫星细胞移植到梗死区,2W后应用免疫组化方法鉴定梗死区VEGF的表达及新生血管密度。结果:骨骼肌卫星细胞在梗死区增殖、分化良好,梗死区VEGF表达移植组明显高于对照组(P<0.05),新生血管密度移植组也高于对照组(P<0.05)。结论:移植区卫星细胞可以分泌生长因子,促进血管形成,改善梗死区细胞的生存环境。     

The mechanisms of hepatic sinusoidal endothelial cell regeneration: A possible communication system associated with vascular endothelial growth factor in liver cells

Vascular endothelial growth factor (VEGF) has been shown to induce proliferation of sinusoidal endothelial cells in primary culture. To elucidate the mechanisms of sinusoidal endothelial cell regeneration in vivo, mRNA expression of VEGF and its receptors, flt-1 and KDR/flk-1, were studied in rat livers. Northern blot analysis revealed that VEGF-mRNA was expressed in hepatocytes immediately after isolation from normal rats. In contrast, non-parenchymal cells, including sinusoidal endothelial cells, expressed VEGF receptor-mRNA. Vascular endothelial growth factor-mRNA expression in hepatocytes was decreased during primary culture, but increased following a peak of DNA synthesis, induced by addition of epidermal growth factor or hepatocyte growth factor to the culture medium at 24 h of plating. In a 70% resected rat liver, VEGF-mRNA expression increased with a peak at 72 h after the operation, and mRNA expression of VEGF receptors between 72 and 168 h. In such a liver, mitosis was maximal in hepatocytes at 36 h and in sinusoidal endothelial cells at 96 h. Also, mRNA expression of both VEGF and its receptors was significantly increased in carbon tetrachloride-intoxicated rat liver compared with normal rat liver. Vascular endothelial growth factor expression was minimal in Kupffer cells isolated from normal rats, but marked in activated Kupffer cells and hepatic macrophages from the intoxicated rats. Vascular endothelial growth factor-mRNA expression was also increased in activated stellate cells from these rats and in the cells activated during primary culture compared with quiescent cells. We conclude that increased levels of VEGF expression in regenerating hepatocytes may contribute to the proliferation of sinusoidal endothelial cells in partially resected rat liver, probably through VEGF receptors up-regulated on the cells. Also, VEGF derived from activated Kupffer cells, hepatic macrophages and stellate cells may be involved in this proliferation in injured rat liver.     

20(s)-原人参二醇对肝癌血管内皮生长因子及碱性成纤维细胞生长因子蛋白表达的影响

目的 探讨20(s)-原人参二醇(Ppd)对肝癌血管内皮生长因子(VEGF)及碱性成纤维细胞生长因子(bFGF)表达的影响.方法 建立肝癌动物模型,将实验动物分为五组,每组10只,分对照组、环磷酰胺组(CTX)、20(s)-原人参二醇25mg/kg、50mg/kg、100mg/kg给药组,给药二周后处死动物.称肿瘤重量及肿瘤体积,制成组织切片,以备免疫组化应用.结果 与对照组相比,给药组VEGF、bFGF表达受到抑制,肿瘤的重量及体积明显减轻,组间有显著性差异(P＜0.01).结论 提示Ppd抑制了VEGF、bFGF蛋白的表达,抑制了肿瘤生长.     

Hypoxia-inducible factor 1 alpha and vascular endothelial growth factor overexpression in ischemic colitis

AIM: To examine the etiology and pathophysiology in human ischemic colitis from the viewpoint of ischemic factors such as hypoxia-inducible factor 1 alpha (HIF-1 alpha and vascular endothelial growth factor (VEGF). METHODS: Thirteen patients with ischemic colitis and 21 normal controls underwent colonoscopy. The follow-up colonoscopy was performed in 8 patients at 7 to 10 d after the occurrence of ischemic colitis. Biopsy samples were subjected to real-time RT-PCR and immunohistochemistry to detect the expression of HIF-1 alpha and VEGF. RESULTS: HIF-1 alpha and VEGF expression were found in the normal colon tissues by RT-PCR and immunohistochemistry. HIF-1 alpha and VEGF were overexpressed in the lesions of ischemic colitis. Overexpressed HIF-1 alpha and VEGF RNA quickly decreased to the normal level in the scar regions at 7 to 10 d after the occurrence of ischemic colitis. CONCLUSION: Constant expression of HIF-1 alpha and VEGF in normal human colon tissue suggested that HIF-1 alpha and VEGF play an important role in maintaining tissue integrity. We confirmed the ischemic crisis in ischemic colitis at the molecular level, demonstrating overexpression of HIF-1 alpha and VEGF in ischemic lesions. These ischemic factors may play an important role in the pathophysiology of ischemic colitis.