血管内皮生长因子及血管内皮生长因子受体在急性肺损伤中作用的研究

血管内皮生长因子是作用于血管内皮细胞的重要血管调节因子,它通过与内皮上的特异受体结合,可发挥促进内皮细胞增殖、分化、诱导血管生成、增加微血管通透性等多种功能.近年研究显示血管内皮生长因子在不同原因、不同阶段急性肺损伤中所起的作用不同.     

单次大剂量阿托伐他汀对不稳定性心绞痛患者血管内皮功能及Rho激酶活性的影响

目的:通过观察单次大剂量阿托伐他汀对不稳定性心绞痛患者血管内皮功能及外周血白细胞Rho激酶活性的影响,探讨他汀改善不稳定性心绞痛患者血管内皮功能的可能机制。方法:入选2012-08至2014-02入住我院的不稳定性心绞痛患者78例,入院当日给予阿托伐他汀80 mg一次顿服。分别于服药前及服药后12 h以超声测反应性充血前后肱动脉内径(FMD)的变化,以免疫印迹法(Western Blot)测外周血白细胞肌球蛋白轻链磷酸酶的肌球蛋白结合亚单位(MYPT1)及在Thr853位上磷酸化的MYPT(1p-MYPT1~(Thr853))蛋白表达,以p-MYPT1~(Thr853)占总MYPT1的百分比表示Rho激酶的活性。结果:患者服用阿托伐他汀80 mg 12 h后,FMD较治疗前增加28.15%[(6.50±1.68)%vs(8.33±1.93)%,P0.001],外周血白细胞Rho激酶活性较治疗前降低32.78%[(58.91±5.22)%vs(39.6±3.85)%,P=0.002]。结论:大剂量阿托伐他汀能快速改善不稳定性心绞痛患者的血管内皮功能,RhoA/Rho激酶通路抑制参与他汀类药物快速改善血管内皮功能的作用。     

血管内皮生长因子在心血管疾病中的作用

血管内皮生长因子是一种高度特异性的促血管内皮细胞生长因子,通过结合相关受体发挥重要的生理功能,具有诱导内皮细胞迁移和增殖、增加血管通透性、调节血栓形成等重要作用。抑制血管内皮生长因子及其受体可引起多种心血管疾病并发症。该文介绍血管内皮生长因子在高血压、冠状动脉粥样硬化性心脏病、肺动脉高压及心力衰竭等心血管疾病中的作用。     

乳腺癌组织中VEGF、VEGF-D、VEGFR-3表达与血管及淋巴管生成的相关性探讨

采用免疫组化SP法检测37例乳腺浸润性导管癌(IDC)和30例正常乳腺组织中血管内皮生长因子(VEGF)、血管内皮生长因子-D(VEGF-D)、血管内皮生长因子受体-3(VEGFR-3)的表达情况及微血管密度(MVD)、淋巴管密度(LVD),并进行相关性分析,结果乳腺IDC中VEGF、VEGFD、VEGFR-3阳性率均高于正常乳腺组织,且与MVD、LVD呈正相关.认为VEGF、VECF-D、VEGFR-3与乳腺IDC的发生、发展有关,其机制可能为促进乳腺组织中血管及淋巴管生成.     

抗血管生成药物治疗非小细胞肺癌的研究进展

抗血管生成药物在非小细胞肺癌(NSCLC)的治疗中起重要作用,能抑制肿瘤的进展.目前研发的抗血管生成药物主要包括结合血管内皮生长因子(VEGF)的单克隆抗体(贝伐单抗、贝伐单抗生物相似制剂)、结合VEGF受体的单克隆抗体(雷莫芦单抗)、结合VEGF受体胞内酪氨酸激酶结构域的抑制剂(尼达尼布、安罗替尼、阿帕替尼、索拉非尼...     

细胞生长因子在胃癌的表达

生长因子是具有刺激细胞生长作用的细胞因子,包括碱性成纤维细胞生长因子(bFGF)、血管内皮细胞生长因子(VEGF)、血小板衍生内皮细胞生长因子(PD-ECGF)、转化生长因子-β(TGF-β)和表皮细胞生长因子(EGF)等.它们通过各种机制降解血管基底膜和周围的细胞外基质,促进内皮细胞分裂、游走和增殖,诱导宿主毛细血管新生并长入肿瘤组织.因此生长因子与肿瘤血管生成、肿瘤的生长和预后的关系成为近年来肿瘤的研究热点,但在胃癌的报道较少.现对不同细胞生长因子在胃癌的表达略作叙述.     

流式细胞术检测口腔鳞癌CD105与VEGF-C、nm23表达的关系

实体肿瘤的浸润生长和转移均需要血管生成,肿瘤新生血管密度是评估患者转移及预后的重要指标,而新生血管内皮主要的标记物为CD105.血管内皮生长因子-C(VEGF-C)是目前所知作用最强的血管生长因子,在肿瘤血管形成过程中起重要作用,并与肿瘤淋巴结转移密切相关;转移抑制基因nm23是一种肿瘤转移抑制基因,肿瘤组织该基因的表达降低是实体瘤浸润生长和转移的必要条件.VEGF-C和nm23在口腔鳞癌中的表达与微血管密度(MVD)及其口腔鳞癌转移的关系目前尚不明确.本文探讨口腔鳞癌VEGF-C、nm23和内皮细胞CD105表达,与局部血管生成及肿瘤侵袭转移的关系.     

急性心肌梗死血管内皮生长因子变化的研究进展

血管内皮生长因子 (VEGF)也称血管通透因子 ,是 1989年Ferrara等分离、纯化出的一种细胞因子 ,它对血管内皮细胞具有高度特异性促有丝分裂作用 ,目前已知多种生长因子和细胞因子具有促进血管生成的作用。然而在众多的血管生成因子中 ,VEGF是最有力的血管生成因子 ,它通过和血管内皮细胞的特异性受体结合 ,具有强大的促内皮增殖、促血管生成作用。其它血管生成因子的血管生成作用是全部或部分通过增强VEGF的表达及生成作用实现的[1] 。1　VEGF的生物学特性VEGF的生物学特性主要表现在两方面 :增加微血管的通透性和特异性与血管内皮…     

结缔组织生长因子在糖尿病肾病中的作用研究进展

结缔组织生长因子具有促进细胞增殖分化、血管生成、基质合成积聚等作用,在糖尿病肾病导致肾小球硬化和肾小管间质纤维化的过程中起关键性作用.通过干预结缔组织生长因子可以缓解糖尿病肾病肾脏纤维化的进展.本文对结缔组织生长因子在糖尿病肾病发生发展中的作用进行综述.     

血管内皮生长因子和内皮抑素在肺纤维化中的作用

血管内皮牛长因子是一种生长因子,在正常肺组织和多种肺部疾病中均有表达.通过血管内皮牛长因子受体发挥生理作用,具有促进内皮细胞分裂增殖、促血管生成、增加血管通透性及抗凋亡等作用.内皮抑素是一种内源性血管生成抑制剂,可以抑制血管内皮细胞增殖、迁移并诱导其调亡,从而达到抑制血管生成作用.在肺纤维化中二者均有异常表达,但具体作...     

RhoA/ROCK信号通路与动脉粥样硬化关系的研究进展

动脉粥样硬化是一种常见的全身性血管疾病,同时也是多种急性心血管疾病的病理基础。而急性心血管疾病的死亡率高,严重危害人们的生命健康。近年来,越来越多的研究表明RhoA/ROCK信号通路与动脉粥样硬化的形成有密切联系。抑制RhoA/ROCK信号通路可以通过稳定血管内皮功能、抑制血管平滑肌细胞增殖和迁移、抑制血管钙化、调控炎症细胞聚集以及抑制血小板增殖变形来延缓或抑制动脉粥样硬化的形成。     

Up-regulation of CPI-17 phosphorylation in diabetic vasculature and high glucose cultured vascular smooth muscle cells

OBJECTIVE: Contractile responses are significantly increased in vascular smooth muscle tissues isolated from type 2 diabetic db/db mice (hyperreactivity). However, the molecular mechanisms underlying this hyperreactivity are largely unknown. The current study investigates the roles of RhoA, ROCK (rho kinase), PKC (protein kinase C), and CPI-17 (protein kinase C-potentiated phosphatase inhibitor of 17 kDa), molecules shown to play pivotal physiological roles regulating smooth muscle contraction, in diabetes-associated vascular smooth muscle hyperreactivity. METHODS: Experiments utilized db/db mouse mesenteric arteries and aortas and primary rat aortic smooth muscle cells (VSMCs) cultured in high or normal glucose. RhoA, ROCK, and CPI-17 protein expression and activity were determined by immunoblotting for total or phosphorylated proteins. RhoA activity was determined by subcellular fractionation and pull-down assays. Isometric contractions were determined using isolated mesenteric artery strips. RESULTS: Active phosphorylated CPI-17 and total and active membrane-bound RhoA were significantly increased in db/db mouse mesenteric arteries and aortas. High glucose time-dependently activated RhoA, ROCK, and CPI-17 in VSMCs. Moreover, inhibiting either RhoA with C3 exoenzyme or ROCK with Y-27632 or H-1152 for 30 min diminished high glucose-induced CPI-17 phosphorylation. Inhibiting protein kinase C (PKC) with GF109203X for 30 min did not inhibit high glucose-induced CPI-17 phosphorylation. Interestingly, when added at the same time as high glucose for a total of 48 h, GF109203X diminished high glucose-induced RhoA and ROCK activation as well as CPI-17 phosphorylation, suggesting PKC is required for high glucose-induced RhoA/ROCK activation and consequently CPI-17 phosphorylation. Importantly, in isolated db/db mouse mesenteric arteries, inhibiting ROCK with Y-27632 or H-1152 significantly alleviated the contractile hyperreactivity in response to phenylephrine or high potassium. CONCLUSIONS: Diabetes and high glucose activate RhoA, ROCK, and CPI-17, which in turn contribute to diabetic vascular smooth muscle hyperreactivity.     

Alpha2-adrenoceptors enhance angiotensin II-induced renal vasoconstriction: role for NADPH oxidase and RhoA

Alpha(2)-adrenoceptors potentiate renal vascular responses to angiotensin II via coincident signaling at phospholipase C. This leads to increased activation of the phospholipase C/protein kinase C/c-src pathway. Studies suggest that c-src activates the reduced nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase/superoxide system, and reactive oxygen species stimulate the RhoA/Rho kinase pathway. Therefore, we hypothesized that NADPH oxidase/superoxide and RhoA/Rho kinase are downstream components of the signal transduction pathway that mediate the interaction between alpha(2)-adrenoceptors and angiotensin II on renal vascular resistance. In rat kidneys, both in vivo and in vitro, intrarenal infusions of angiotensin II increased renal vascular resistance, and UK14,304 (alpha(2)-adrenoceptor agonist) enhanced this response. Intrarenal Tempol (superoxide dismutase mimetic) or Y27632 (Rho kinase inhibitor) abolished the interaction between UK14,304 and angiotensin II both in vivo and in vitro. The interaction was also blocked by inhibitors of NADPH oxidase (in vivo using chronic gp91ds-tat administration and in vitro with diphenyleneiodonium). In cultured preglomerular vascular smooth muscle cells, UK14,304 enhanced angiotensin II-induced intracellular superoxide (2-hydroxyethidium production) and potentiated activation of RhoA (Western blot of activated RhoA bound to the binding domain of rhotekin). The interaction between angiotensin II and UK14,304 on superoxide generation and RhoA activation was blocked by inhibitors of phospholipase C (U73312), protein kinase C (GF109203X), c-src (PP1), NADPH oxidase (diphenyleneiodonium), or superoxide (Tempol). We conclude that NADPH oxidase/superoxide and RhoA/Rho kinase are involved in the interaction between alpha(2)-adrenoceptors and angiotensin II on renal vascular resistance by mediating signaling events downstream of the phospholipase C/protein kinase C/c-src pathway.     

HMG-CoA reductase inhibitor simvastatin suppresses Toll-like receptor 2 ligand-induced activation of nuclear factor kappa B by preventing RhoA activation in monocytes from rheumatoid arthritis patients

To investigate whether anti-inflammatory effects of HMG-CoA reductase inhibitor simvastatin (SMV) in rheumatoid arthritis (RA) is mediated by Toll-like receptor-2 (TLR-2) signal via inhibiting activation of RhoA, a small Rho GTPase that plays an important role in inflammatory responses. Peripheral blood monocytes from active RA patients were treated with Staphylococcus aureus peptidoglycan (PG), a ligand of TLR-2, in the presence or absence of SMV. RhoA activity was assessed by a pull-down assay. DNA-binding activity was measured by a sensitive multi-well colorimetric assay. Cytokine secretion was measured by ELISA. PG stimulation increased the level of active GTP-bound RhoA compared with unstimulated monocytes, and the effect of PG on RhoA activity was suppressed with anti-TLR-2 monoclonal antibody. RhoA inhibition either with a specific inhibitor or by siRNA transfection inhibited activation of NF-κB and secretion of TNFα and IL-1β in PG-induced RA monocytes. SMV mitigated PG-induced increase in RhoA activity and NF-κB activation as well as secretion of TNFα and IL-1β. The inhibitory effects of SMV were completely reversed by mevalonate and geranylgeranyl pyrophosphate. Our results indicate the modulation of RhoA on TLR-2-mediated inflammatory signaling in RA and provide a novel evidence for anti-inflammatory effects of statins through influencing TLR-2 signaling via RhoA in RA.     

The hematopoietic cell-specific Rho GTPase inhibitor ARHGDIB/D4GDI limits HIV type 1 replication

Rho GTPases are able to influence the replication of human immunodeficiency virus type 1 (HIV-1). However, little is known about the regulation of HIV-1 replication by guanine nucleotide dissociation inhibitors (GDIs), one of the three major regulators of the Rho GTPase activation cycle. From a T cell-based cDNA library screening, ARHGDIB/RhoGDIβ, a hematopoietic lineage-specific GDI family protein, was identified as a negative regulator of HIV-1 replication. Up-regulation of ARHGDIB attenuated the replication of HIV-1 in multiple T cell lines. The results showed that (1) a significant portion of RhoA and Rac1, but not Cdc42, exists in the GTP-bound active form under steady-state conditions, (2) ectopic ARHGDIB expression reduced the F-actin content and the active forms of both RhoA and Rac1, and (3) HIV-1 infection was attenuated by either ectopic expression of ARHGDIB or inhibition of the RhoA signal cascade at the HIV-1 Env-dependent early phase of the viral life cycle. This is in good agreement with the previous finding that RhoA and Rac1 promote HIV-1 entry by increasing the efficiency of receptor clustering and virus-cell membrane fusion. In conclusion, the ARHGDIB is a lymphoid-specific intrinsic negative regulator of HIV-1 replication that acts by simultaneously inhibiting RhoA and Rac1 functions.     

Neutrophil polarization: spatiotemporal dynamics of RhoA activity support a self-organizing mechanism

Chemoattractants like fMet-Leu-Phe (fMLP) induce neutrophils to polarize with phosphatidylinositol 3,4,5-trisphosphate (PIP3) and protrusive F-actin at the front and actomyosin contraction at the sides and back. RhoA and its downstream effector, myosin II, mediate the "backness" response, which locally inhibits the "frontness" response and constrains its location to one part of the cell. In living HL-60 cells, we used a fluorescent PIP3 probe or a single-chain FRET biosensor for RhoA-GTP to assess spatial distribution of frontness or backness responses, respectively, during the first 3 min after exposure to a uniform concentration of fMLP. Increased PIP3 signal or RhoA activity initially localized randomly about the cell's periphery but progressively redistributed to the front or to the back and sides, respectively. Cells rendered unable to mount the frontness response (by inhibiting actin polymerization or Gi, a trimeric G protein) responded to a micropipette source of attractant by localizing RhoA activity at the up-gradient edge. We infer that protrusive F-actin, induced by the frontness response, constrains the spatial distribution of backness by locally reducing activation of RhoA, thereby reducing its active form at the front. Mutual incompatibility of frontness and backness is responsible for self-organization of neutrophil polarity.     

Dual role for RhoA in suppression and induction of cytokines in the human neutrophil

Production of tumor necrosis factor-alpha (TNFalpha) by the neutrophil (PMN) is a pivotal event in innate immunity, but the signals regulating TNFalpha induction in this primary cell are poorly understood. Herein, we use protein transduction to identify novel, opposing anti- and pro-cytokine-inducing roles for RhoA in the resting and lipopolysaccharide (LPS)-stimulated human PMN, respectively. In the resting cell, RhoA suppresses Cdc42 activation, IkappaBalpha degradation, nuclear factor-kappaB (NF-kappaB) activation, and induction of TNFalpha and NF-kappaB-dependent chemokines. Suppression of TNFalpha induction by RhoA is Rho kinase alpha (ROCKalpha) independent, but Cdc42 dependent, because TNFalpha induction by C3 transferase is attenuated by inhibition of Cdc42, and constitutively active Cdc42 suffices to activate NF-kappaB and induce TNFalpha. By contrast, we also place RhoA downstream of p38 mitogen-activated protein kinase and Cdc42 in a novel LPS-activated pathway in which p38, Cdc42, and ROCKalpha all promote TNFalpha protein expression. The p65 subunit of NF-kappaB coprecipitates with RhoA in a manner sensitive to the RhoA activation state. Our findings suggest a new, 2-faced role for RhoA as a checkpoint in innate immunity.     

RhoA and RhoC -siRNA inhibit the proliferation and invasiveness activity of human gastric carcinoma by Rho/PI3K/Akt pathway

AIM： To evaluate the effects of adenovirus-mediated gene transfer of RhoA siRNA and RhoC siRNA on proliferation and invasion of SGC7901 cells by Rho/ PI3K/Akt pathway.
METHODS： Plasmid of RhoA siRNA and RhoC siRNA were constructed and transfected into SGC7901 cells. siRNA and LY294002 （PI3K inhibitor） were designed as the control group. The mRNA and protein expressions of RhoA and RhoC were respectively detected with RT-PCR and western blotting. In order to find out the changes of proliferation and invasion power of SGC7901 cell lines, we analyzed the data by MTT, Boyden chamber and evaluated apoptosis of cell with flow cytometry. We treated BALB/C nude mice with RhoA and RhoC-siRNA, and tumor control rate （%） in nude mice was calculated.
RESULTS： RhoA and RhoC siRNA transfections specifically down-regulated the corresponding mRNA and protein levels in SGC7901 Cells.The experiment of permeated artificial basal membrane showed that the invasion power of SGC7901 cell lines are on the decline after treatment of Ad-RhoA and RhoC-siRNA （12.64 ±3.27 vs 87.38±17.38, P 〈 0.05）. The values of 490 nm wavelength light absorption were different in the five groups. The number of alive cells in the group of RhoA and RhoC-siRNA was lower than others in the 6^th d （0.71 ± 0.01 vs 3.82± 0.11 P 〈 0.05）. The apoptosis rate of transfected RhoA and RhoC-siRNA group with FACS were 19.07% ± 1.78 and there were significant differences between treated and control groups （19.07 ± 1.78% vs 1.23± 0.11%, P 〈 0.01）. The tumor transplantation experiment in BALB/C nude mice showed intratumoral injection of RhoA or RhoC siRNA can inhibit tumor growth.
CONCLUSION： RhoA and RhoC siRNA gene therapy mediated by adenovirus may be useful for inhibiting growth and invasion of SGC7901 through a PI3K/Akt pathway. These results provide a novel therapeutic target in preventing gastric cancer cell invasion and metastasis.     

17β-Estradiol inhibits apoptotic cell death of oligodendrocytes by inhibiting RhoA-JNK3 activation after spinal cord injury

A delayed oligodendrocyte cell death after spinal cord injury (SCI) contributes to chronic demyelination of spared axons, leading to a permanent neurological deficit. Therefore, therapeutic approaches to prevent oligodendrocyte cell death after SCI should be considered. Estrogens are well known to have a broad neuroprotective effect, but the protective effect of estrogens on oligodendrocytes after injury is largely unknown. Here, we demonstrated that 17β-estradiol attenuates apoptosis of oligodendrocytes by inhibiting RhoA and c-Jun-N-terminal kinase activation after SCI. Estrogen receptor (ER)-α and -β were expressed in oligodendrocytes of the spinal cord, and 17β-estradiol treatment significantly inhibited oligodendrocyte cell death at 7 d after injury as compared with vehicle (cyclodextrin) control. 17β-Estradiol also attenuated caspase-3 and -9 activation at 7 d and reduced the loss of axons from progressive degeneration. In addition, 17β-estradiol inhibited RhoA and JNK3 activation, which were activated and peaked at 3 and/or 5 d after injury. Furthermore, administration of Rho inhibitor, PEP-1-C3 exoenzyme, inhibited RhoA and JNK3 activation, and decreased phosphorylated c-Jun level at 5 d after injury. Additionally, the attenuation of RhoA and JNK3 activation as well as oligodendrocyte cell death by 17β-estradiol was reversed by ER antagonist, ICI182780. Our results thus indicate that 17β-estradiol treatment improves functional recovery after SCI in part by reducing oligodendrocyte cell death via inhibition of RhoA and JNK3 activation, which were ER dependent. Furthermore, improvement of hindlimb motor function by posttreatment of 17β-estradiol suggests its potential as a therapeutic agent for SCI patients.