Monocyte chemoattractant protein-1 (MCP-1) gene polymorphism as a potential risk factor for cardiovascular disease in hemodialyzed patients

Aim: Polymorphism in the monocyte chemoattractant protein-1 (MCP-1) gene (A-2518G) has been associated with functional effects. The aim of the present study was to assess the effect of this polymorphism on end-stage renal disease (ESRD) and cardiovascular disease (CVD) in hemodialyzed patients. Methods: A total of 720 patients with ESRD treated with hemodialysis (450 patients with CVD) and 325 healthy control subjects were genotyped for the MCP-1 -2518 polymorphism by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) procedure. Results: There was a significant difference in genotype frequencies between entire group of hemodialyzed patients and controls (p < 0.01). The odds ratio for the risk allele was 1.85, 95% CI 1.49–2.32 (p < 0.01). Hemodialyzed patients were divided into subgroups with CVD (n = 450) and without CVD (n = 270). The G allele carriers occurred with significantly higher frequency in patients with CVD (62% vs. 38% in patients without CVD and 36% in controls). The odds ratio for the risk allele for patients with CVD vs. those without CVD was 2.17, 95% CI 1.71–2.79. There was no statistically significant difference in the distribution of MCP-1 genotypes between ESRD patients without CVD and healthy controls. Conclusion: Our results demonstrate for the first time an association between the polymorphism in the regulatory region of the MCP-1 gene and susceptibility to CVD in hemodialyzed patients.     

Endogenous Production of β-Chemokines by CD4+, but Not CD8+, T-Cell Clones Correlates with the Clinical State of Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Individuals and May Be Responsible for Blocking Infection with NonSyncytium-Inducing HIV-1 In Vitro

Recent studies have demonstrated that the β-chemokines RANTES, MIP-1α, and MIP-1β suppress human immunodeficiency virus type 1 (HIV-1) replication in vitro and may play an important role in protecting exposed but uninfected individuals from HIV-1 infection. However, levels of β-chemokines in AIDS patients are comparable to and can exceed levels in nonprogressing individuals, indicating that global β-chemokine production may have little effect on HIV-1 disease progression. We sought to clarify the role of β-chemokines in nonprogressors and AIDS patients by examination of β-chemokine production and HIV-1 infection in patient T-lymphocyte clones established by herpesvirus saimiri immortalization. Both CD4⁺ and CD8⁺ clones were established, and they resembled primary T cells in their phenotypes and expression of activated T-cell markers. CD4⁺ T-cell clones from all patients had normal levels of mRNA-encoding CCR5, a coreceptor for non-syncytium-inducing (NSI) HIV-1. CD4⁺ clones from nonprogressors and CD8⁺ clones from AIDS patients secreted high levels of RANTES, MIP1α, and MIP-1β. In contrast, CD4⁺ clones from AIDS patients produced no RANTES and little or no MIP-1α or MIP-1β. The infection of CD4⁺ clones with the NSI HIV-1 strain ADA revealed an inverse correlation to β-chemokine production; clones from nonprogressors were poorly susceptible to ADA replication, but clones from AIDS patients were highly infectable. The resistance to ADA infection in CD4⁺ clones from nonprogressors could be partially reversed by treatment with anti-β-chemokine antibodies. These results indicate that CD4⁺ cells can be protected against NSI-HIV-1 infection in culture through endogenously produced factors, including β-chemokines, and that β-chemokine production by CD4⁺, but not CD8⁺, T cells may constitute one mechanism of disease-free survival for HIV-1-infected individuals.     

A Pattern of Early Radiation-Induced Inflammatory Cytokine Expression Is Associated with Lung Toxicity in Patients with Non-Small Cell Lung Cancer

Purpose

Lung inflammation leading to pulmonary toxicity after radiotherapy (RT) can occur in patients with non-small cell lung cancer (NSCLC). We investigated the kinetics of RT induced plasma inflammatory cytokines in these patients in order to identify clinical predictors of toxicity.

Experimental Design

In 12 NSCLC patients, RT to 60 Gy (30 fractions over 6 weeks) was delivered; 6 received concurrent chemoradiation (chemoRT) and 6 received RT alone. Blood samples were taken before therapy, at 1 and 24 hours after delivery of the 1^st fraction, 4 weeks into RT, and 12 weeks after completion of treatment, for analysis of a panel of 22 plasma cytokines. The severity of respiratory toxicities were recorded using common terminology criteria for adverse events (CTCAE) v4.0.

Results

Twelve cytokines were detected in response to RT, of which ten demonstrated significant temporal changes in plasma concentration. For Eotaxin, IL-33, IL-6, MDC, MIP-1α and VEGF, plasma concentrations were dependent upon treatment group (chemoRT vs RT alone, all p-values <0.05), whilst concentrations of MCP-1, IP-10, MCP-3, MIP-1β, TIMP-1 and TNF-α were not. Mean lung radiation dose correlated with a reduction at 1 hour in plasma levels of IP-10 (r² = 0.858, p<0.01), MCP-1 (r² = 0.653, p<0.01), MCP-3 (r² = 0.721, p<0.01), and IL-6 (r² = 0.531, p = 0.02). Patients who sustained pulmonary toxicity demonstrated significantly different levels of IP-10 and MCP-1 at 1 hour, and Eotaxin, IL-6 and TIMP-1 concentration at 24 hours (all p-values <0.05) when compared to patients without respiratory toxicity.

Conclusions

Inflammatory cytokines were induced in NSCLC patients during and after RT. Early changes in levels of IP-10, MCP-1, Eotaxin, IL-6 and TIMP-1 were associated with higher grade toxicity. Measurement of cytokine concentrations during RT could help predict lung toxicity and lead to new therapeutic strategies.     

Circulating beta-chemokines and matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 system in hemodialyzed patients--role of oxidative stress

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), beta-chemokines, increased oxidative stress (SOX) and inflammation have been implicated as important factors in atherosclerosis and vascular remodeling. We hypothesized the possible roles of beta-chemokines [monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory proteins (MIP-1alpha, MIP-1beta) and regulated upon activation, normal T-cell expressed and secreted (RANTES)] as regulators of the metabolism of the vascular extracellular matrix in conditions of increased SOX in hemodialysis (HD) patients. We compared pre-dialysis levels of MMP-9/TIMP-1 system, beta-chemokines, Cu/Zn superoxide dismutase (Cu/Zn SOD) as a marker of SOX and C-reactive protein (CRP) as a marker of inflammation in HD patients with and without cardiovascular disease (CVD) to those of controls. HD patients, particularly those with CVD, showed a significant increase in values of Cu/Zn SOD, CRP, TIMP-1, TIMP-1/MMP-9 ratio, MCP-1 and MIP-1beta, whereas RANTES levels were lower than in the controls. The levels of MIP-1alpha as well as MMP-9 in all HD groups were similar to the controls. The positive correlations were observed between the MMP-9/TIMP-1 system and beta-chemokines, SOX and inflammation in whole HD group and in the subgroup with CVD. Multivariate analysis showed that the duration of dialysis followed by Cu/Zn SOD, MIP-1alpha and beta levels were the significant positive predictors of TIMP-1. In conclusion, our data show that MMP-9/TIMP-1 system and beta-chemokines could cooperate in conditions of elevated SOX, which ultimately predisposes hemodialysis patients to accelerated atherosclerosis.     

Serum fetuin--a concentrations are inversely related to cytokine concentrations in patients with chronic renal failure

Background/Aims: A close relationship exists between inflammation and vascular calcification. Although fetuin-A is known to be an inhibitor of calcification, studies correlating levels of this glycoprotein to markers of inflammation are limited. To understand these relationships, we investigated the relationship between serum fetuin-A and proinflammatory cytokine levels in patients with chronic renal failure (CRF). Methods: Thirty-two patients on haemodialysis (HD), 32 conservatively managed chronic kidney disease (CKD) patients and a control group of 25 subjects with normal renal function were enrolled in this study. Serum fetuin-A, IL-1β, IL-6 and TNF-α levels were measured by ELISA. Correlations between serum fetuin-A and IL-1β, IL-6 and TNF-α concentrations were investigated by the Spearman correlation test. Results: In 64 CRF patients (on HD and with CKD), serum fetuin-A was significantly and inversely related to IL-1β (P < 0.001), IL-6 (P = 0.025) and TNF-α levels (P = 0.007), respectively. The serum fetuin-A levels of the control subjects were not significantly correlated to levels of the inflammatory markers IL-1β, IL-6 and TNF-α (P = 0.551, 0.985 and 0.984, respectively). Conclusion: The negative correlation between serum fetuin-A and cytokine concentrations in CRF patients supports the hypothesis of inflammation-dependent down-regulation of fetuin-A expression.     

Associations of interleukin-6 with interleukin-1beta, interleukin-8 and macrophage inflammatory protein-1beta in midlife women

Objective: The aim of the present study was to determine the associations of interleukin (IL)-6 with other cytokines and chemokines and to compare these associations in peri- and postmenopausal women. Methods: Ninety-nine perimenopausal and 92 postmenopausal women were enrolled in this study. Serum concentrations of IL-6, IL-1β, IL-2, IL-4, IL-5, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, tumor necrosis factor (TNF)-α, interferon γ, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage (GM)-CSF, macrophage inflammatory protein (MIP)-1β and monocyte chemotactic protein (MCP)-1 were measured simultaneously using a multiplexed cytokine assay. Results: Among the 17 cytokines, IL-6, IL-1β, IL-5, IL-7, IL-8, IL-10, MCP-1 and MIP-1β were detected in serum in more than 50% of the women. Serum levels of IL-4 and MCP-1 in postmenopausal women were significantly higher than those in perimenopausal women. Serum IL-6 concentrations showed significant and positive correlations with serum concentrations of IL-1β, IL-8, MIP-1β, IL-7 and MCP-1 in women regardless of menopausal status, and these correlations were still significant after adjustment for age and body mass index. Conclusion: Serum IL-6 concentration was found to be closely associated with serum concentrations of IL-1β, IL-8, MIP-1β, IL-7 and MCP-1 in women regardless of menopausal status, suggesting that these cytokines act in concert with the progression of several symptoms and various diseases.     

l-Cysteine supplementation lowers blood glucose, glycated hemoglobin, CRP, MCP-1, and oxidative stress and inhibits NF-κB activation in the livers of Zucker diabetic rats

This study examined the hypothesis that l-cysteine supplementation can lower insulin resistance, glycemia, oxidative stress, and markers of vascular inflammation in type 2 diabetes using Zucker diabetic fatty (ZDF) rats as a model. Starting at the age of 6 weeks, ZDF rats were supplemented orally (daily gavage, 8 weeks) with saline placebo (D) or l-cysteine (LC; 1 mg/kg bw) and fed a high-calorie diet. Six-week-old rats without any supplementation were considered baseline (BL) rats. D rats showed elevated fasting blood glucose, glycated Hb, CRP, and MCP-1 compared with BL rats in which there was no onset of diabetes. LC supplementation significantly lowered blood levels of glucose (18%, p =  0.05), glycated Hb (8%, p =  0.02), CRP (23%, p =  0.02), MCP-1 (32%, p =  0.01), and insulin resistance (25%) compared with levels seen in saline-supplemented D rats. There was a decrease in plasma protein oxidation levels (p <  0.01); however, GSH levels were similar in LC and D groups. Although LC did not change blood hematocrit or levels of transaminases, it did lower alkaline phosphatase (29%, p =  0.01) levels in comparison to D. Western blotting analyses of liver showed increased activation of NF-κB and Akt (50% pNF-κB and 20% pAkt) in D compared with BL rats. LC supplementation inhibited these effects (17% pAkt, 18% pNF-κB). This is the first report showing that l-cysteine supplementation can lower glycemia and markers of vascular inflammation in diabetes apparently by preventing NF-κB activation in a diabetic animal model.     

Autocrine Production of β-Chemokines Protects CMV-Specific CD4+ T Cells from HIV Infection

Induction of a functional subset of HIV-specific CD4⁺ T cells that is resistant to HIV infection could enhance immune protection and decrease the rate of HIV disease progression. CMV-specific CD4⁺ T cells, which are less frequently infected than HIV-specific CD4⁺ T cells, are a model for such an effect. To determine the mechanism of this protection, we compared the functional response of HIV gag-specific and CMV pp65-specific CD4⁺ T cells in individuals co-infected with CMV and HIV. We found that CMV-specific CD4⁺ T cells rapidly up-regulated production of MIP-1α and MIP-1β mRNA, resulting in a rapid increase in production of MIP-1α and MIP-1β after cognate antigen stimulation. Production of β-chemokines was associated with maturational phenotype and was rarely seen in HIV-specific CD4⁺ T cells. To test whether production of β-chemokines by CD4⁺ T cells lowers their susceptibility to HIV infection, we measured cell-associated Gag DNA to assess the in vivo infection history of CMV-specific CD4⁺ T cells. We found that CMV-specific CD4⁺ T cells which produced MIP-1β contained 10 times less Gag DNA than did those which failed to produce MIP-1β. These data suggest that CD4⁺ T cells which produce MIP-1α and MIP-1β bind these chemokines in an autocrine fashion which decreases the risk of in vivo HIV infection.     

House dust mite, Dermatophagoides pteronissinus increases expression of MCP-1, IL-6, and IL-8 in human monocytic THP-1 cells

The house dust mite (Dermatophagoides pteronissinus) plays an important role in the pathogenesis of allergic diseases, including atopic dermatitis, and asthma. Monocyte chemotactic protein 1 (MCP-1/CCL2)/IL-6/IL-8 (CXCL8) plays a pivotal role in mediating the infiltration of various cells into the skin of atopic dermatitis and psoriasis. The aim of this study was to investigate the effect of D. pteronissinus extract (DpE) on expression of MCP-1/IL-6/IL-8 mRNA and protein and the signal transduction in the human monocytic cell line, THP-1. The mRNA and protein expression of MCP-1/CCL2, IL-6, and IL-8 were elevated by DpE in a time and dose-dependent manner in THP-1 cells. The increased expression of MCP-1, IL-6, and IL-8 was not affected by aprotinin (serine protease inhibitor) or E64 (cysteine protease inhibitor). We found that MCP-1 and IL-6 expression due to DpE was related to Src, protein kinase C δ (PKC δ), extracellular-signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) and IL-8 expression was involved in Src family tyrosine kinase, PKC δ, ERK. DpE increased the phosphorylation of ERK and p38 MAPK after 5 min and peaked at 30 min. The activation was significantly blocked by PP2, an inhibitor of Src family tyrosine kinase and rottlerin, an inhibitor of PKC δ (p < 0.01). DpE increases MCP-1, IL-6, and IL-8 expression and transduces its signal via Src family tyrosine kinase, PKC, and ERK in a protease-independent manner. This finding may contribute to the elucidation of the pathogenic mechanism triggered by DpE .     

Synovial explant inflammatory mediator production corresponds to rheumatoid arthritis imaging hallmarks: a cross-sectional study

Introduction

Despite the widespread use of magnetic resonance imaging (MRI) and Doppler ultrasound for the detection of rheumatoid arthritis (RA) disease activity, little is known regarding the association of imaging-detected activity and synovial pathology. The purpose of this study was to compare site-specific release of inflammatory mediators and evaluate the corresponding anatomical sites by examining colour Doppler ultrasound (CDUS) and MRI scans.

Methods

RA patients were evaluated on the basis of CDUS and 3-T MRI scans and subsequently underwent synovectomy using a needle arthroscopic procedure of the hand joints. The synovial tissue specimens were incubated for 72 hours, and spontaneous release of monocyte chemoattractant protein 1 (MCP-1), interleukin 6 (IL-6), macrophage inflammatory protein 1β (MIP-1β) and IL-8 was measured by performing multiplex immunoassays. Bone marrow oedema (BME), synovitis and erosion scores were estimated on the basis of the rheumatoid arthritis magnetic resonance imaging score (RAMRIS). Mixed models were used for the statistical analyses. Parsimony was achieved by omitting covariates with P > 0.1 from the statistical model.

Results

Tissue samples from 58 synovial sites were obtained from 25 patients. MCP-1 was associated with CDUS activity (P = 0.009, approximate Spearman’s ρ = 0.41), RAMRIS BME score (P = 0.01, approximate Spearman’s ρ = 0.42) and RAMRIS erosion score (P = 0.03, approximate Spearman’s ρ = 0.31). IL-6 was associated with RAMRIS synovitis score (P = 0.04, approximate Spearman’s ρ = 0.50), BME score (P = 0.04, approximate Spearman’s ρ = 0.31) and RAMRIS erosion score (P = 0.03, approximate Spearman’s ρ = 0.35). MIP-1β was associated with CDUS activity (P = 0.02, approximate Spearman’s ρ = 0.38) and RAMRIS synovitis scores (P = 0.02, approximate Spearman’s ρ = 0.63). IL-8 associations with imaging outcome measures did not reach statistical significance.

Conclusions

The association between imaging activity and synovial inflammatory mediators underscores the high sensitivity of CDUS and MRI in the evaluation of RA disease activity. The associations found in our present study have different implications for synovial mediator releases and corresponding imaging signs. For example, MCP-1 and IL-6 were associated with both general inflammation and bone destruction, in contrast to MIP-1β, which was involved solely in general synovitis. The lack of association of IL-8 with synovitis was likely underestimated because of a large proportion of samples above assay detection limits among the patients with the highest synovitis scores.     

High susceptibility to respiratory Acinetobacter baumannii infection in A/J mice is associated with a delay in early pulmonary recruitment of neutrophils

Acinetobacter baumannii is an important cause of both community-associated and nosocomial pneumonia, which have become increasingly difficult to treat because of the rapid development of resistance to multiple antibiotics. Despite its clinical importance, the pathogenesis of and host defense against respiratory A. baumannii infection remains largely unknown. To examine host factors that could contribute to the defense, we compared the susceptibilities of A/J and C57BL/6 mice to intranasal (i.n.) inoculation with A. baumannii. We found that A/J mice were significantly more susceptible to infection with higher mortality (P < 0.05) and tissue bacterial burdens (P < 0.01) as well as greater histopathology in the lung and spleen than C57BL/6 mice. More importantly, the high susceptibility of A/J mice was associated with a reduced local proinflammatory cytokine/chemokine (particularly IL-1β, MIP-2 and TNF-α) responses and a significant delay and reduction in the early influx of neutrophils in the lung (P < 0.05). Intranasal administration of neutrophil-inducing chemokine MIP-2 to A/J mice enhanced pulmonary neutrophil influx and partially restored host resistance to A. baumannii to a level comparable to the more resistant C57BL/6 mice. Our results imply that the early recruitment of neutrophils into the lung is critical for initiating an efficient host defense against respiratory A. baumannii infection.     

Delayed parturition in cloned calves associated with persistently elevated placentomal TGF-β1 expression

The objective of this study was to investigate hormonal and TGF-β₁ characterizations of delayed parturition in the SCNT recipients (Korean native beef cattle: Hanwoo). The SCNT blastocysts produced by Hanwoo fetal fibroblast cells were transferred into the synchronized Hanwoo recipients. The artificially inseminated Hanwoo recipients (AI-R) were used as control. All AI-R were labored by natural delivery. The SCNT recipients (SCNT-R) with no signs of delivery were operated by Caesarean section. The blood and placentomes were collected during parturition. The weight of placentomes in SCNT-R (n = 12, 301 ± 41.22 g) was significantly higher than that of AI-R (n = 10, 204.8 ± 24.89 g) (p < 0.05). There were significantly lower E2 (p < 0.05) or higher P4 (p < 0.01) and TGF-β₁ (p < 0.01) levels in the SCNT-R compared to that of AI-R, respectively. The SCNT-R showed a higher placentomal TGF-β₁ protein level compared to that of AI-R (p < 0.01). Interestingly, the TGF-β₁ protein level in SCNT-R with normal delivery was dramatically decreased as same as AI-R, but it was highly maintained in C-sec at days 250 of pregnancy in AI-R. These results suggest that delayed parturition in clone calving may be associated with persistence of elevated TGF-beta-1 expression in late pregnancy.     

Increased Pro-Inflammatory Cytokines,C-Reactive Protein and Nerve Growth Factor Expressions in Serum of Patients with Interstitial Cystitis/Bladder Pain Syndrome

Objective

The etiology and pathogenesis of interstitial cystitis/bladder pain syndrome (IC/BPS) are unclear. Chronic inflammation is considered the main pathology of IC/BPS. This study measured the serum c-reactive protein (CRP), nerve growth factor (NGF) and pro-inflammatory cytokine/chemokine interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-8 expression in patients with IC/BPS to elucidate the involvement of systemic inflammation in IC/BPS.

Methods

Serum samples were collected from 30 IC/BPS patients and 26 control subjects. The concentrations of serum nerve growth factor (NGF), IL-1β, IL-6, TNF-α, and IL-8 were quantified using a bead-based, human serum adipokine panel kit. Serum C-reactive protein (CRP) was also assessed. Differences of serum CRP, NGF, IL-1β, IL-6, TNF-α, and IL-8 levels between the IC/BPS patients and controls were compared, and correlations between CRP and pro-inflammatory cytokines and chemokine were also evaluated.

Results

The results showed that CRP level (p = 0.031), NGF (p = 0.015) and pro-inflammatory cytokines/chemokine IL-1β, IL-6, TNF-α, and IL-8 levels were significantly higher in the patients with IC/BPS than among controls (all p<0.001). Significant associations were observed between IL-1β and IL-8 (p<0.001), IL-6 and CRP (p = 0.01), IL-6 and IL-8 (p = 0.02), and IL-6 and TNF-α (p = 0.03).

Conclusion

Increased pro-inflammatory cytokines/chemokine (IL-1β, IL-6, TNF-α, and IL-8) expression in the sera of IC/BPS patients implies not only mast cell activation, but also that other inflammatory mediators play important roles in the pathogenesis of IC/BPS. Thus, for some patients, IC/BPS is considered a chronic inflammatory disease.     

Chemokine PARC Gene (SCYA18) Generated by Fusion of Two MIP-1α/LD78α-like Genes

Two loci in the human genome, chromosomes 4q12–q21 and 17q11.2, contain clusters of CXC and CC chemokine subfamily genes, respectively. Since mice appear to contain fewer chemokine genes than humans, numerous gene duplications might have occurred in each locus of the human genome. Here we describe the genomic organization of the human pulmonary and activation-regulated CC chemokine (PARC), also known as DC-CK1 and AMAC-1. Despite high sequence similarity to a CC chemokine macrophage inflammatory protein-1α (MIP-1α)/LD78α, PARC is chemotactic for lymphocytes and not for monocytes and does not share its receptor with MIP-1α. Analyses of the BAC clones containing the humanPARCgene indicated that the gene is located most closely toMIP-1α(HGMW-approved symbolSCYA3) andMIP-1β(HGMW-approved symbolSCYA4) on chromosome 17q11.2. Dot-plot comparison suggested that thePARCgene had been generated by fusion of twoMIP-1α-like genes with deletion and selective usage of exons. Base changes accumulated before and after the fusion might have adapted the gene to a new function. Since there are variably duplicated copies of theMIP-1αgene calledLD78β(HGMW-approved symbolSCYA3L) in the vicinity of theMIP-1αgene, the locus surrounding theMIP-1αgene seems to be a “hot spring” that continuously produces new family genes. This evidence provides a new model, duplication and fusion, of the molecular basis for diversity within a gene family.     

Therapeutic dose of nebivolol, a nitric oxide-releasing β-blocker, reduces atherosclerosis in cholesterol-fed rabbits

Nitric oxide (NO) exerts a plethora of vascular beneficial effects. The NO-releasing β-blocker nebivolol is a racemic mixture of d/l-enantiomers that displays negative inotropic as well as direct vasodilating activity. The in vivo antiatherogenic activity of therapeutic doses of the β-blocker with antioxidant properties carvedilol (12.5 mg/day) or nebivolol (5 mg/day) was tested in cholesterol-fed rabbits. Animals received a 1% cholesterol-rich diet alone (controls) or mixed with drugs (treated animals) for 8 weeks. While it did not affect hyperlipidemia, nebivolol inhibited the development of atherosclerosis, expressed as computer-assisted imaging analysis of aortic area covered by lesions (23.3 ± 4.1% in treated vs 38.2 ± 6.4% in control animals, p < 0.01). Differently, in our experimental condition of therapeutic drug doses, this antiatherogenic effect did not reach statistical significance in rabbits treated with carvedilol (32.5 ± 5.1% aortic area covered by lesions, p = NS vs controls). Plasma nitrates increased in rabbits treated with nebivolol while both β-blockers reduced LDL oxidation. Moreover, nebivolol induced a consistent increase of endothelial reactivity and aortic eNOS expression compared with control animals (p < 0.05) and those receiving carvedilol (p < 0.05). Since NO may exert beneficial effects in atherosclerosis, a NO-dependent mechanism could explain this data. These observations suggest that the NO-releasing β-blocker, nebivolol, might represent an effective pharmacological approach for preventing atherosclerotic lesion progression.     

Assessment of the genotoxicity of imidacloprid and metalaxyl in cultured human lymphocytes and rat bone-marrow

Imidacloprid and metalaxyl are two pesticides that are widely used in agriculture, either separately, or in combination. These agents were studied for their possible genotoxic effects with respect to the following cytogenetic end-points: (1) in vitro micronucleus (MN) formation and sister-chromatid exchange (SCE) induction in human lymphocytes and (2) in vivo micronucleus induction in polychromatic erythrocytes (PCEs) of the rat bone-marrow. The results of the MN analysis indicate that MN frequencies after treatment with both pesticides, separately or as a mixture, do not significantly differ from those in the controls except after treatment with metalaxyl alone at 50 μg/ml (p < 0.05). The results of the SCE analysis show that SCE frequencies after treatment with imidacloprid do not differ significantly from those in the controls. A statistically significant increase (p < 0.05) in SCE frequency resulted from treatments with metalaxyl at 5, 10 and 100 μg/ml and with the combination of imidacloprid and metalaxyl at 100 and 200 μg/ml. Finally, the in vivo micronucleus assay with rat bone-marrow polychromatic erythrocytes showed a statistically significant effect upon separate treatments with imidacloprid and metalaxyl at doses of 300 mg/kg body weight (b.w.) (p < 0.01) or upon combined treatment with 200 mg/Kg b.w. (p < 0.001) and 400 mg/kg b.w. (p < 0.05).     

Serum Levels of Monocyte Chemoattractant Protein-1 and All-Cause and Cardiovascular Mortality among Patients with Coronary Artery Disease

Background

Monocyte chemoattractant protein-1 (MCP-1) is an important chemokine at multiple phases of atherosclerosis in animals, but human studies are few and inconsistent. The aim of this study is to investigate the association of serum MCP-1with all-cause and cardiovascular disease (CVD) mortality among coronary artery disease (CAD) patients and determine whether this biomarker can add secondary prognostic value to standard risk predictors.

Methods

MCP-1 was measured at baseline in 1411 CAD patients who were 40–85 years of age. Cox proportional hazards regression models were used to estimate the association of MCP-1 levels with death risk.

Results

During a median follow-up of 3.3 years, 117 deaths were recorded, 88 of which were due to CVD. The multivariable-adjusted hazard ratios across tertiles of MCP-1 were 1.51 (95% confidence intervals [CI] 0.89–2.58), 1.00, and 2.11 (95% CI 1.31–3.40) for all-cause mortality, and 1.50 (95% CI 0.80–2.81), 1.00, and 2.21 (95% CI 1.27–3.87) for CVD mortality. The addition of serum MCP-1 to the fully adjusted model increased the C-index by 0.009 (p<0.0001) for all-cause mortality and 0.008 (p<0.0001) for CVD mortality and significantly improved the predictive ability by 12.1% (P = 0.006) on all-cause mortality and 12.6% (P = 0.003) on CVD mortality using the net reclassification improvement method.

Conclusions

Both lower and higher MCP-1 levels are associated with an increased risk of all-cause and CVD mortality among CAD patients. More research is needed to confirm its clinical relevance.     

Monocyte chemoattractant protein-1 (MCP-1) gene polymorphism as a potential risk factor for cardiovascular disease in hemodialyzed patients

Aim: Polymorphism in the monocyte chemoattractant protein-1 (MCP-1) gene (A-2518G) has been associated with functional effects. The aim of the present study was to assess the effect of this polymorphism on end-stage renal disease (ESRD) and cardiovascular disease (CVD) in hemodialyzed patients. Methods: A total of 720 patients with ESRD treated with hemodialysis (450 patients with CVD) and 325 healthy control subjects were genotyped for the MCP-1 -2518 polymorphism by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) procedure. Results: There was a significant difference in genotype frequencies between entire group of hemodialyzed patients and controls (p < 0.01). The odds ratio for the risk allele was 1.85, 95% CI 1.49–2.32 (p < 0.01). Hemodialyzed patients were divided into subgroups with CVD (n = 450) and without CVD (n = 270). The G allele carriers occurred with significantly higher frequency in patients with CVD (62% vs. 38% in patients without CVD and 36% in controls). The odds ratio for the risk allele for patients with CVD vs. those without CVD was 2.17, 95% CI 1.71–2.79. There was no statistically significant difference in the distribution of MCP-1 genotypes between ESRD patients without CVD and healthy controls. Conclusion: Our results demonstrate for the first time an association between the polymorphism in the regulatory region of the MCP-1 gene and susceptibility to CVD in hemodialyzed patients.     

C-terminal fragment of transforming growth factor beta-induced protein (TGFBIp) is required for apoptosis in human osteosarcoma cells

Transforming growth factor beta-induced protein (TGFBIp), is secreted into the extracellular space. When fragmentation of C-terminal portions is blocked, apoptosis is low, even when the protein is overexpressed. If fragmentation occurs, apoptosis is observed. Whether full-length TGFBIp or integrin-binding fragments released from its C-terminus is necessary for apoptosis remains equivocal. More importantly, the exact portion of the C-terminus that conveys the pro-apoptotic property of TGFBIp is uncertain. It is reportedly within the final 166 amino acids. We sought to determine if this property is dependent upon the final 69 amino acids containing the integrin-binding, EPDIM and RGD, sequences. With MG-63 osteosarcoma cells, transforming growth factor (TGF)-β1 treatment increased expression of TGFBIp over 72 h (p < 0.001). At this time point, apoptosis was significantly increased (p < 0.001) and was prevented by an anti-TGFBIp, polyclonal antibody (p < 0.05). Overexpression of TGFBIp by transient transfection produced a 2-fold increase in apoptosis (p < 0.01). Exogenous purified TGFBIp at concentrations of 37–150 nM produced a dose dependent increase in apoptosis (p < 0.001). Mass spectrometry analysis of TGFBIp isolated from conditioned medium of cells treated with TGF-β1 revealed truncated forms of TGFBIp that lacked integrin-binding sequences in the C-terminus. Recombinant TGFBIp truncated, similarly, at amino acid 614 failed to induce apoptosis. A recombinant fragment encoding the final 69 amino acids of the TGFBIp C-terminus produced significant apoptosis. This apoptosis level was comparable to that induced by TGF-β1 upregulation of endogenous TGFBIp. Mutation of the integrin-binding sequence EPDIM, but not RGD, blocked apoptosis (p < 0.001). These pro-apoptotic actions are dependent on the C-terminus most likely to interact with integrins.