Doxycycline decreases monocyte chemoattractant protein-1 in human lung epithelial cells

Certain antibiotics possess anti-inflammatory properties and could potentially be used to treat inflammatory lung diseases associated with an influx of monocytes such as panbronchiolitis, asthma, cystic fibrosis, and bronchitis. Doxycycline is reported to possess anti-inflammatory effects. Monocyte chemoattractant protein-1 (MCP-1) is a major inflammatory cytokine and a powerful chemoattractant for monocytes. The authors hypothesized that doxycycline exerts its anti-inflammatory effects, in part, by reducing MCP-1 production. To test this hypothesis, A549 human lung epithelial cells were stimulated with cytomix in the presence or absence of doxycycline. In stimulated cells doxycycline decreased MCP-1 production by 95% and in monocyte chemotaxis assays migration decreased by 55%. However, doxycycline did decrease expression of MCP-1 mRNA and did not effect its stability. These data demonstrate that doxycycline modulates MCP-1 production and suggest that doxycycline may provide a new anti-inflammatory therapy for chronic lung diseases.     

Serum of cytomegalovirus-infected mice induces monocyte chemoattractant protein-1 expression by endothelial cells

Inflammation plays a central role in atherogenesis. It was hypothesized that infection of apolipoprotein E-deficient mice with murine cytomegalovirus (MCMV) increases serum levels of proinflammatory cytokines, which may induce "proatherosclerotic" changes in endothelial cells (ECs). Serum samples were collected from uninfected and infected mice. ELISA was used to determine cytokine serum levels and monocyte chemoattractant protein-1 (MCP-1) levels in the supernatant of mouse ECs incubated with serum-containing medium. Serum samples from infected mice induced MCP-1 expression by ECs. These serum samples contain interferon (IFN)-gamma, whereas IFN-gamma was undetectable in serum samples from uninfected mice. Preincubating infected mouse serum with anti-IFN-gamma monoclonal antibody significantly decreased serum-induced EC expression of MCP-1. Thus, MCMV infection increases IFN-gamma serum levels, such serum can induce MCP-1 in ECs, and the serum-induced MCP-1 expression is due, at least in part, to IFN-gamma. If these changes in EC function also occur in vivo in response to infection, they could exacerbate atherogenesis.     

结直肠癌趋化因子单核细胞超化蛋白-1的表达

目的：通过检测结直肠癌组织中单核细胞超化蛋白－1（MPC－1）的表达情况，研究MCP－1的表达与结直肠癌生物学行为的关系。方法：采用RT－PCR方法，检测临床收集的新鲜结肠癌组织标本中MCP－1mRNA的表达；采用免疫组化方法，检测结直肠癌组织中MCP－1蛋白的表达，结果：12例结直肠癌组织均可出现MCP－1mRNA的表达，40例结直肠癌组织MCP－1蛋白表达的阳性率为90％，结直肠癌组织MCP－1蛋白的表达与结直肠癌的转移及Dukes分期有关，表达强者，转移发生率低，Dukes分期早，结论：结直肠组织中MCP－1的表达能影响结直肠癌的生物学行为。     

硒对人脐静脉内皮细胞ECV-304单核细胞趋化蛋白-1表达的影响

目的 观察硒对人脐静脉内皮细胞ECV-304单核细胞趋化蛋白-1(MCP-1)表达的影响方法分别用高葡萄糖、糖基化终末产物，高胰岛素和过氧化氢孵育人脐静脉内皮细胞ECV-304；在先加入100nmol／L硒后，再给予以上4种因素．分别检测人脐静脉内皮细胞ECV0304MCP-1mRNA的表达并比较。结果 4种因素均可作为独立因素，导致人脐静脉内皮细胞ECV304MCP-1mRNA表达量增加：硒能抑制4种因素所致的MCP-1mRNA表达。结论 硒抑制MCP-1 mRNA在人脐静脉内皮细胞ECV-304中的表达。     

血管紧张素Ⅱ对人脐静脉内皮细胞单核细胞趋化因子-1表达的影响

目的　探讨血管紧张素Ⅱ (AngⅡ )对人脐静脉内皮细胞 (HUVECs)分泌单核细胞趋化因子 1(MCP 1)的影响。方法　用RT PCR和ELISA方法检测AngⅡ在不用时间和浓度以及氯沙坦干预后对HUVECs分泌MCP 1的影响。结果　AngⅡ显著刺激HUVECs表达MCP 1,MCP 1mRNA分别在AngⅡ的浓度为 1× 10 - 7mol/L和刺激 4h时表达最强烈 ;而MCP 1蛋白质分泌随刺激时间延长而增加 ;氯沙坦干预则明显减低MCP 1的表达。结论　AngⅡ可强烈刺激HUVECs表达MCP 1,氯沙坦可拮抗该作用     

Aspirin inhibits monocyte chemoattractant protein-1 and interleukin-8 expression in TNF-alpha stimulated human umbilical vein endothelial cells

Atherosclerosis and its complications such as stroke, myocardial infraction and peripheral vascular disease, remain the major causes of morbidity and mortality in the world. Studies have showed that chemokines and adhesion molecules are involved in causing atherosclerosis by promoting directed migration of inflammatory cells. Monocyte chemoattractant protein-1 (MCP-1) is one of the key factors critical for the initiating and developing of atherosclerotic lesions. IL-8, a CXC chemokine, stimulates neutrophil chemotaxis. Aspirin is the most common drug used to prevent the complications of atherosclerosis such as stroke and coronary heart disease. In this study, we found that aspirin inhibited TNF-alpha (10 ng/ml)-induced MCP-1 and IL-8 expression at the RNA and protein levels in human umbilical vein endothelial cells (HUVECs), monocyte adhesion and transmigration, and that its inhibitory effects were not due to decreased HUVEC viability as assessed by MTT test. Aspirin at the dose as low as 10 microg/ml significantly inhibited the release of TNF-stimulated MCP-1 by 29.1% (P = 0.008) and IL-8 by 26.9% (P = 0.0146) as compared to TNF-stimulated release. Antibodies pretreatment were likely to decrease the production of MCP-1 (P < 0.0001) and IL-8 (P < 0.0001). Furthermore, aspirin (10 microg/ml) inhibited U937 cell adhesion by a 13.4% (P = 0.0119) inhibition as compared to TNF-stimulated alone. Finally, at higher concentration, aspirin also inhibited U937 migration to HUVEC by 89.1% (P = 0.0475) as compared to TNF-stimulated alone. These results in our study suggest that aspirin inhibits TNF-alpha stimulated MCP-1 and IL-8 release in HUVECs, for its additional therapeutic effects of aspirin in causing atherosclerosis.     

Inhibitory effect of troglitazone on TNF-alpha-induced expression of monocyte chemoattractant protein-1 (MCP-1) in human endothelial cells

Insulin resistance is one of the risk factors for the progression of atherosclerosis. Recently, the new oral insulin-sensitizing drug troglitazone is thought to offer potential in the treatment of diabetes. If adopted for such use, this drug might be helpful in protecting against the development of atherosclerosis and microvascular complications via its improvement of insulin resistance. However, it has not yet been clarified whether troglitazone acts directly on the vascular cells and inhibits the progression of atherosclerosis. Meanwhile, Monocyte chemoattractant protein-1 (MCP-1) is known to play an important role in the pathogenesis of atherosclerosis by inducing monocyte migration. Therefore, we investigated the effect of troglitazone on the expression of MCP-1 in human umbilical vein endothelial cells (HUVECs). HUVECs were treated with or without troglitazone (1 or 10 microM) in the presence or absence of various concentrations of tumor necrosis factor-alpha (TNF-alpha) (5, 50 or 500 ng/ml), and then the amounts of MCP-1 secreted from the HUVECs were measured. We found that TNF-alpha increased the secretions of MCP-1 119-fold vs. control, and that troglitazone significantly inhibited this TNF-alpha-induced increase in MCP-1 secretions (19.4%). Moreover, Northern blot analysis revealed that troglitazone decreased the MCP-1 mRNA level in HUVECs. Our present studies indicated that troglitazone may prevent the progression of atherosclerosis by inhibiting MCP-1 expression in endothelial cells.     

Inhibitory effect of troglitazone on tumor necrosis factor alpha-induced expression of monocyte chemoattractant protein-1 in human mesangial cells

Insulin resistance is one of the risk factors for the progression of atherosclerosis and glomerulosclerosis. Recently, the new oral insulin-sensitizing agent troglitazone has been thought to offer potential in the treatment of diabetes. If adopted for this use, it might be helpful in protecting against the development of atherosclerosis and microvascular complications via its improvement of insulin resistance. However, it has not yet been clarified whether troglitazone acts directly on the vascular cells and inhibits the progression of atherosclerosis, including glomerulosclerosis. Meanwhile, monocyte chemoattractant protein-1 (MCP-1) is known to play an important role in the pathogenesis of atherosclerosis and glomerulosclerosis through the induction of monocyte migration. Therefore, we investigated the effect of troglitazone on the expression of MCP-1 in human mesangial cells (HMCs). HMCs were treated with or without troglitazone (1 or 10 micromol/L) in the presence or absence of tumor necrosis factor alpha (TNF-alpha) at various concentrations (50 or 500 ng/mL), and then MCP-1 secretion from the HMCs was measured. We found that TNF-alpha increased the secretion of MCP-1 by 55-fold versus the control and troglitazone significantly inhibited this TNF-alpha-induced increase in MCP-1 secretion (49.3%). Moreover, Northern blot analysis showed that troglitazone decreased the MCP-1 mRNA level in HMCs. We demonstrated that alpha-tocopherol also inhibited TNF-alpha-induced MCP-1 production in HMCs, although its effects were not as strong as troglitazone. The present study indicates that troglitazone may prevent the progression of atherosclerosis by inhibiting MCP-1 expression in mesangial cells.     

阿托伐他汀对晚期糖基化终末产物诱导的人内皮细胞单核细胞趋化蛋白-1mRNA表达影响及其机制的实验研究

目的 观察阿托伐他汀对晚期糖基化终末产物(advanced glycation end products,AGE)诱导的人脐静脉内皮细胞表达单核细胞趋化蛋白-1(MCP-1)的影响,并探讨其作用机制.方法 实验分组:(1)空白对照组.(2)牛血清白蛋白(BSA)对照组.(3)AGE诱导组:不同作用浓度的AGE(10-4、10-3、10-2及10-1g/L)与细胞共同培养24 h.(4) AGE+阿托伐他汀组:用不同作用浓度的阿托伐他汀(0.1、1、10 μmol/L)分别与细胞培养1 h,而后加入10-1 g/L AGE[根据(3)实验结果选取最佳浓度]与细胞共孵育24 h.(5)PPAR-γ激动剂(15 d-PGJ2)组:15 d-PGJ2( 10 μmol/L)与细胞孵育1 h后加入10-1 g/L AGE再与细胞共孵育24 h.(6)PPAR-γ抑制剂(GW9662)组:GW9662(5000 g/L)与细胞孵育1 h后加入AGE(10-1 g/L)和阿托伐他汀(1 μmol/L)[根据(4)实验结果选取最佳浓度]再与细胞共孵育24 h.胶原酶消化法获取人脐静脉内皮细胞.逆转录聚合酶链反应法分析细胞MCP-1和过氧化物酶增殖物活化受体γ(PPAR-γ)基因的表达.蛋白免疫印迹法测定细胞核因子-κB(NF-κB )p65表达水平.结果 (1)AGE(10-4、10-3、10-2及10-1 g/L)呈浓度依赖性提高人脐静脉内皮细胞MCP-1 mRNA表达水平,分别是空白对照组的1.53倍、2.12倍、2.56倍及4.71倍;AGE浓度为10-4 g/L时,细胞MCP-1 mRNA表达明显高于空白对照组(0.26±0.02比0.17±0.04,P<0.01).(2)与AGE组比,阿托伐他汀(0.1、1、10 μmol/L)呈浓度依赖性抑制AGE诱导的人内皮细胞MCP-1 mRNA的表达;阿托伐他汀浓度为1 μmol/L时,细胞MCP-1 mRNA表达水平显著低于AGE(10-1g/L)组(0.63±0.11比1.03±0.07,P<0.01).(3)AGE(10-1 g/L)组人脐静脉内皮细胞PPAR-γ mRNA的表达水平显著低于空白对照组(0.22±0.08比0.69±0.09,P<0.01),磷酸化和非磷酸化NF-κB p65蛋白表达水平显著高于空白对照组(0.78±0.06比0.31±0.01和1.61±0.16 比0.59±0.14,P均<0.01).(4)阿托伐他汀(1、10 μmol/L)组人脐静脉内皮细胞PPAR-γ mRNA表达水平显著高于AGE(10-1 g/L)组(0.59±0.02和0.61±0.06比0.22±0.08,P均<0.01);阿托伐他汀(1 μmol/L)组磷酸化和非磷酸化NF-κB p65蛋白表达水平显著低于AGE(10-1g/L)组(0.40±0.03比0.78±0.06和0.65±0.12比1.61±0.16,P均<0.01).(5)PPAR-γ激动剂(15 d-PGJ2)组细胞磷酸化和非磷酸化NF-κB p65蛋白表达水平显著低于AGE(10-1g/L)组 (0.21±0.01比0.78±0.06和0.67±0.14比1.61±0.16,P均<0.01),MCP-1 mRNA表达水平显著低于AGE(10-1g/L)组(0.17±0.02比0.93±0.12,P<0.01).(6)PPAR-γ抑制剂(GW9662)组细胞磷酸化和非磷酸化NF-κB p65蛋白表达水平显著高于AGE(10-1g/L)+阿托伐他汀(1 μmol/L)组(0.53±0.02比0.40±0.03和1.38±0.18比0.65±0.12,P均<0.01),MCP-1 mRNA表达水平显著高于AGE(10-1g/L)+阿托伐他汀(1 μmol/L)组(0.62±0.05比0.30±0.07,P<0.01).结论 阿托伐他汀可通过提高AGE诱导的人脐静脉内皮细胞对PPAR-γ表达抑制细胞NF-κB信号途径,进而抑制AGE诱导的人脐静脉内皮细胞的炎性反应.

Abstract：

Objective To investigate the effects of atorvastatin on advanced glycation end products (AGE) induced monocyte chemoattractant protein-1(MCP-1) expression in human umbilical vein endothelial cells(HUVECs)and whether this effect could be linked to peroxisome proliferator-activated receptor-γ (PPAR-γ) and nuclear factor-κB(NF-κB).Methods Grouping: (1)Blank control group;(2)BSA group;(3)AGE group:cells were incubated with different concentrations of AGE(10-4,10-3, 10-2 and 10-1g/L)for 24 hours; (4)AGE+Atorvastatin group: cells were incubated with different concentrations of atorvastatin(0.1,1,10 μmol/L)for 1 hour,then incubated with AGE (10-1 g/L) for 24 hours; (5)PPAR-γ agonist(15 d-PGJ2)group: cells were incubated with 15 d-PGJ2(10 μmol/L)for 1 hour,then incubated with AGE (10-1g/L) for 24 hours;(6)PPAR-γ inhibitor(GW9662)group:cells were incubated with GW9662(5000 nmol/L)for 1 hour,then incubated with atorvastatin (1 μmol/L)and AGE (10-1g/L) for 24 hours. Collagenase was used to isolate the endothelial cell from human umbilical vein;RT-PCR was performed to examine the mRNA expression of MCP-1 and PPAR-γ;Western blot was performed to detect NF-κB p65 protein.Results (1) The expression of MCP-1 mRNA was increased in proportion with increasing concentrations of AGEs which could be blocked by atorvastatin in a dose-dependent manner. (2) AGE(10-1g/L)significantly downregulated the expression of PPAR-γ mRNA(0.22±0.08 vs. 0.69±0.09, P<0.01) while upregulated the expression of phospho-NF-κB p65 protein (0.78±0.06 vs. 0.31±0.01,P<0.01) and nonphospho-NF-κB p65 protein (1.61±0.16 vs. 0.59±0.14,P<0.01) comparaed with the control group which could be significantly attenuated by atorvastatin. (3) PPAR-γ agonist decreased the expression of phospho-NF-κB p65 protein (0.21±0.01 vs. 0.78±0.06, P<0.01),nonphospho-NF-κB p65 protein (0.67±0.14 vs. 1.61±0.16,P<0.01)and MCP-1 mRNA (0.17±0.02 vs. 0.93±0.12, P<0.01)compared with AGE(10-1g/L)group. (4) PPAR-γ inhibitor antagonized the effect of atorvastatin on the expression of phospho-NF-κB p65 protein, nonphospho-NF-κB p65 protein and MCP-1 mRNA stimulated by AGE in HUVECs(P<0.01).Conclusion The anti-inflammatory properties of atorvastatin in AGE stimulated HUVECs may partly be attributed to the effect on upregulation of PPAR-γ and downregulation of NF-κB signaling pathway.     

Homocysteine mediated expression and secretion of monocyte chemoattractant protein-1 and interleukin-8 in human monocytes

Homocysteine (Hcy) is an independent risk factor for cardiovascular disease. Monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) are major chemokines for leukocyte trafficking and have been identified in atheromatous plaques. MCP-1 and IL-8 have been found to express mainly by macrophages in human lesion. We undertook this study to determine whether Hcy could induce the secretion of chemokines from human monocytes and, if so, to explore the mediating mechanism. We found that clinically relevant levels of Hcy (10 to 1000 micromol/L) increased the protein secretion and mRNA expression as well as activity of MCP-1 and IL-8 in cultured primary human monocytes. These effects of Hcy were primarily mediated by reactive oxygen species (ROS) through NAD(P)H oxidase, because Hcy could upregulate the production of ROS and the inhibitors of protein kinase C, calmodulin, free radical scavengers, or NAD(P)H oxidase abolished Hcy-induced ROS production and MCP-1 and IL-8 secretion in these cells. Furthermore, the inhibitors of mitogen-activated protein kinase (p38 and extracellular signal-regulated kinase 1/2) and nuclear factor-kappaB or the activator of peroxisome proliferator-activated receptor gamma (PPARgamma) significantly decreased Hcy-induced MCP-1 and IL-8 secretion in these cells. These data indicate that pathophysiological levels of Hcy can alter human monocyte function by upregulating MCP-1 and IL-8 expression and secretion via enhanced formation of intracellular ROS originated from NAD(P)H oxidase source via calmodulin or protein kinase C signaling pathways and that Hcy-induced ROS subsequently activates mitogen-activated protein kinase (p38 and ERK1/2) and nuclear factor-kappaB in a PPARgamma activator-sensitive manner. Thus, activation of PPARgamma may become a therapeutic target for preventing Hcy-induced proatherogenic effects.     

单核细胞趋化蛋白-1在系统性硬化症患者中的表达

目的 探讨单核细胞趋化蛋白-1（MCP-1）在系统性硬化症（SSc）的相关性。方法 采用酶联免疫吸附试验（ELISA）方法检测27例SSc患者血浆MCP-1水平，并与21名年龄和性别相匹配的健康志愿者血浆中浓度对照，同时采用反转录聚合酶链反应（RT-PCR）和免疫组织化学染色方法检测MCP-1mRNA和蛋白质在5例SSc患者和3名健康志愿者皮肤成纤维细胞中的表达。结果 血浆MCP-1水平SSc组为（787±393）pg／ml，明显高于健康志愿者组的（426±266）pg/ml（P〈0．05）。对SSc组的进一步分析显示，11例弥漫型SSc患者血浆MCP-1水平为（896±347）pg／ml，高于16例局限型SSc患者的（714±332）pg/ml（P〈0．05）；18例并发有肺间质纤维化的SSc患者血浆MCP-1水平（844±327）pg／ml，也高于9例无肺间质纤维化的SSc患者的（676±314）pg／ml（P〈0．05）。RT-PCR和免疫组织化学染色的结果显示，5例分离于SSc病变皮肤、在体外培养的成纤维细胞有MCP-1的mRNA和蛋白质分子表达，而3名取自健康志愿者皮肤的成纤维细胞则无表达。结论 SSc患者血浆MCP-1水平显著升高，而且与皮肤受累程度和肺间质纤维化有一定的关系。RT-PCR和免疫组织化学染色结果表明，SSc患者病变皮肤组织表达MCP-1增高，提示MCP-1在SSc的病程中起重要作用。     

9-cis retinoic acid induces monocyte chemoattractant protein-1 secretion in human monocytic THP-1 cells.

Monocyte migration and activation are regulated by monocyte chemoattractant protein-1 (MCP-1). Prior studies have shown MCP-1 expression is modulated by a variety of ligands that act through extracellular receptors. In the current study, we show 9-cis retinoic acid (RA), a ligand for the nuclear hormone receptor retinoid X receptor (RXR) and retinoic acid receptor (RAR), markedly induces the expression of MCP-1. In human THP-1 monocytic leukemia cells cultured with RA (0.05 to 500 nmol/L), MCP-1 expression was induced rapidly, significantly, and dose-dependently by as much as 165-fold. MCP-1 RNA level was also increased in RA-treated cells. Expression of PPARgamma, a heterodimer partner of RXR, is also markedly induced by RA in THP-1 cells. However, BRL49653, a PPARgamma ligand, failed to induce MCP-1 secretion either alone or to modify the expression level induced by RA. In contrast, BRL49653 significantly increased MCP-1 (biotinylated MCP-1) binding to THP-1 cells, whereas RA had no effect. Other peroxisome proliferator activated receptor (PPAR) ligands, 15d-PGJ(2) and troglitazone (PPARgamma), Wy14,643 (PPARalpha), and PD195599 (PPARbeta) inhibited the induction of MCP-1 by RA. RA's effect on MCP-1 expression in human elutriated monocytes were similar to that observed in the THP-1 cells. These studies identify RA as a nuclear signal for MCP-1 induction in undifferentiated human monocytic cells. These studies also suggest monocyte MCP-1 expression induced through RA may modulate cell migration.     

茶多酚抑制人血管内皮细胞分泌单核细胞趋化蛋白1的研究

目的通过对人血管内皮细胞炎性分子单核细胞趋化蛋白1(MCP-1)的检测,评价茶多酚在血脂异常中对血管内皮的保护作用及其作用机制。方法应用人血管内皮细胞为研究模型,在基础或者氧化型低密度脂蛋白刺激的条件下,给予不同剂量的茶多酚,并与其他抗氧化剂水溶性维生素E(Trolox)、银杏提取物(EGb761)相比较,检测不同时间点细胞培养基当中的MCP-1含量。结果 24 h内浓度小于200μmol/L的茶多酚对内皮细胞没有明显的毒性作用,并且可以剂量依赖性地抑制内皮MCP-1的分泌(均为P<0.05)。与未处理组及其他抗氧化剂组相比,茶多酚处理组显著地降低了MCP-1的基因表达和蛋白分泌水平,并呈剂量依赖性,表现出较好的内皮保护及抗炎作用。结论与其他抗氧化剂相比,茶多酚可以在脂质氧化的条件下更好地通过抑制炎性因子的表达和分泌来保护内皮细胞。     

Significance of the level of monocyte chemoattractant protein-1 in human atherosclerosis.

BACKGROUND: Monocyte chemoattractant protein-1 (MCP-1), a potent chemoattractant for monocytes, plays an important role in the earliest events of atherogenesis. However, direct evidence of the effects of MCP-1 on atherosclerosis in chronic hemodialysis (HD) patients has not been reported. METHODS AND RESULTS: The serum MCP-1 concentrations and the intimal - medial thickness (IMT) in the carotid arteries were measured in 42 non-diabetic chronic HD patients and 20 age-matched controls. The expression of MCP-1 was examined immunohistochemically in radial arterial tissues obtained from the HD patients. IMT and the serum concentration of MCP-1 in the HD patients were both significantly greater than in controls. Multiple regression analysis revealed that the serum concentration of MCP-1 was an independent factor influencing IMT. Tissue immunostaining showed that MCP-1 is expressed in both endothelial and smooth muscle cells and that its level of expression correlates with the serum concentration of MCP-1. CONCLUSIONS: An increase in MCP-1 may be an important factor in the progression of atherosclerosis in non-diabetic HD patients.