Age intrinsic loss of telomere protection via TRF1 reduction in endothelial cells.

Aging is a major factor predisposing for multiple diseases. Telomeres at the ends of chromosomes protect the integrity of chromosomal DNA. A specialized six-protein complex termed shelterin protects the telomere from unwanted interaction with DNA damage pathways. The aim of our study was to evaluate the integrity of telomeres and the stability of telomere protection during aging in endothelial cells (EC). We describe that aging EC can be characterized by an increased cell size (40%, p=0.02) and increased expression of PAI 1 (4 fold, p=0.02), MCP1 (10 fold, p=0.001) and GMCSF (15 fold, p=0.004). Telomeric state in aging cells is defined by an increased telomere oxidation (27%, p=0.01), reduced telomere length (62%, p=0.02), and increased DNA damage foci formation (5% in young EC versus 16% in aged EC, p=0.003). This telomeric dysfunction is accompanied by a reduction in the shelterin component TRF1 (33% mRNA, p=0.001; 24% protein, p=0.007). Overexpression of TRF1 in aging EC reduced telomere-associated DNA damage foci to 5% (p=0.02) and reduced expression levels of MCP1 (18% reduction, p=0.008). Aged EC have increased telomere damage and an intrinsic loss of telomere protection. Reestablishing telomere integrity could therefore be a target for rejuvenating endothelial cell function.

Reduced Ang2 expression in aging endothelial cells.

Aging endothelial cells are characterized by increased cell size, reduced telomere length and increased expression of proinflammatory cytokines. In addition, we describe here that aging reduces the migratory distance of endothelial cells. Furthermore, we observe an increase of the quiescence protein Ang1 and a decrease of the endothelial activation protein Ang2 upon aging. Supplementing Ang2 to aged endothelial cells restored their migratory capacity. We conclude that aging shifts the balance of the Ang1/Ang2 network favouring a quiescent state. Activation of endothelial cells in aging might be necessary to enhance wound healing capacities.

Beneficial effects of levosimendan on survival in patients undergoing extracorporeal membrane oxygenation after cardiovascular surgery.

BACKGROUND: The impact of levosimendan treatment on clinical outcome in patients undergoing extracorporeal membrane oxygenation (ECMO) support after cardiovascular surgery is unknown. We hypothesized that the beneficial effects of levosimendan might improve survival when adequate end-organ perfusion is ensured by concomitant ECMO therapy. We therefore studied the impact of levosimendan treatment on survival and failure of ECMO weaning in patients after cardiovascular surgery. METHODS: We enrolled a total of 240 patients undergoing veno-arterial ECMO therapy after cardiovascular surgery at a university-affiliated tertiary care centre into our observational single-centre registry. RESULTS: During a median follow-up period of 37 months (interquartile range 19-67 months), 65% of patients died. Seventy-five per cent of patients received levosimendan treatment within the first 24 h after initiation of ECMO therapy. Cox regression analysis showed an association between levosimendan treatment and successful ECMO weaning [adjusted hazard ratio (HR) 0.41; 95% confience interval (CI) 0.22-0.80; P=0.008], 30 day mortality (adjusted HR 0.52; 95% CI 0.30-0.89; P=0.016), and long-term mortality (adjusted HR 0.64; 95% CI 0.42-0.98; P=0.04). CONCLUSIONS: These data suggest an association between levosimendan treatment and improved short- and long-term survival in patients undergoing ECMO support after cardiovascular surgery.

Evolving biomarkers improve prediction of long-term mortality in patients with stable coronary artery disease: the BIO-VILCAD score.

OBJECTIVE: Algorithms to predict the future long-term risk of patients with stable coronary artery disease (CAD) are rare. The VIenna and Ludwigshafen CAD (VILCAD) risk score was one of the first scores specifically tailored for this clinically important patient population. The aim of this study was to refine risk prediction in stable CAD creating a new prediction model encompassing various pathophysiological pathways. Therefore, we assessed the predictive power of 135 novel biomarkers for long-term mortality in patients with stable CAD. DESIGN, SETTING AND SUBJECTS: We included 1275 patients with stable CAD from the LUdwigshafen RIsk and Cardiovascular health study with a median follow-up of 9.8 years to investigate whether the predictive power of the VILCAD score could be improved by the addition of novel biomarkers. Additional biomarkers were selected in a bootstrapping procedure based on Cox regression to determine the most informative predictors of mortality. RESULTS: The final multivariable model encompassed nine clinical and biochemical markers: age, sex, left ventricular ejection fraction (LVEF), heart rate, N-terminal pro-brain natriuretic peptide, cystatin C, renin, 25OH-vitamin D3 and haemoglobin A1c. The extended VILCAD biomarker score achieved a significantly improved C-statistic (0.78 vs. 0.73; P = 0.035) and net reclassification index (14.9%; P < 0.001) compared to the original VILCAD score. Omitting LVEF, which might not be readily measureable in clinical practice, slightly reduced the accuracy of the new BIO-VILCAD score but still significantly improved risk classification (net reclassification improvement 12.5%; P < 0.001). CONCLUSION: The VILCAD biomarker score based on routine parameters complemented by novel biomarkers outperforms previous risk algorithms and allows more accurate classification of patients with stable CAD, enabling physicians to choose more personalized treatment regimens for their patients.

Transtemporal ultrasound application potentially elevates brain temperature: results of an anthropomorphic skull model.

PURPOSE: Transtemporal sonothrombolysis is a tool for a more effective treatment in acute stroke patients. However, some reports revealed side effects, which might be potentially connected to temperature elevation. To gain better insight into cerebral temperature changes during transtemporal sonication, diagnostic and therapeutic ultrasound (US) applications were evaluated using an anthropomorphic skull model. MATERIALS AND METHODS: The impact of diagnostic (PW-Doppler, 1.8-MHz, 0.11 W/cm², TIC 1.2) and therapeutic (1-MHz and 3-MHz, 0.07 - 0.71 W/cm², continuous and pulsed mode) US application on temperature changes was evaluated at the level of muscle/temporal bone (TB), TB/brain, brain and at the middle cerebral artery (MCA) using 4 miniature thermocouples along the US beam. Sonication lasted 120 minutes. RESULTS: Diagnostic ultrasound revealed a maximum temperature increase of 1.45°/0.60°/0.39°/0.41°C (muscle/TB, TB/brain, brain, MCA) after 120 minutes. Therapeutic-1-MHz ultrasound raised temperature by 4.33°/2.02°/1.05 °C/0.81°C (pulsed 1:20) and by 10.38°/4.95°/2.43°/2.08°C (pulsed 1:5) over 120 minutes. Therapeutic-3-MHz US raised temperature by 4.89°/2.56°/1.24/1.25°C (pulsed 1:20) and by 14.77°/6.59°/3.56°/2.86°C (pulsed 1:5) over 120 minutes, respectively. Continuous application of therapeutic US (1-MHz and 3-MHz) led to a temperature increase of 13.86°/3.63°/1.66°/1.48°C and 17.09°/4.28°/1.38/0.99°C within 3 minutes. CONCLUSION: Diagnostic PW-Doppler showed only a moderate temperature increase and can be considered as safe. Therapeutic sonication is very powerful in delivering energy so that even pulsed application modes resulted in significant and potentially harmful temperature increases.

Breaking the rules: sex roles and genetic mating system of the pheasant coucal.

Generally in birds, the classic sex roles of male competition and female choice result in females providing most offspring care while males face uncertain parentage. In less than 5% of species, however, reversed courtship sex roles lead to predominantly male care and low extra-pair paternity. These role-reversed species usually have reversed sexual size dimorphism and polyandry, confirming that sexual selection acts most strongly on the sex with the smaller parental investment and accordingly higher potential reproductive rate. We used parentage analyses and observations from three field seasons to establish the social and genetic mating system of pheasant coucals, Centropus phasianinus, a tropical nesting cuckoo, where males are much smaller than females and provide most parental care. Pheasant coucals are socially monogamous and in this study males produced about 80% of calls in the dawn chorus, implying greater male sexual competition. Despite the substantial male investments, extra-pair paternity was unusually high for a socially monogamous, duetting species. Using two or more mismatches to determine extra-pair parentage, we found that 11 of 59 young (18.6%) in 10 of 21 broods (47.6%) were not sired by their putative father. Male incubation, starting early in the laying sequence, may give the female opportunity and reason to seek these extra-pair copulations. Monogamy, rather than the polyandry and sex-role reversal typical of its congener, C. grillii, may be the result of the large territory size, which could prevent females from monopolising multiple males. The pheasant coucal's exceptional combination of classic sex-roles and male-biased care for extra-pair young is hard to reconcile with current sexual selection theory, but may represent an intermediate stage in the evolution of polyandry or an evolutionary remnant of polyandry.

Avian embryonic development does not change the stable isotope composition of the calcite eggshell.

The avian embryo resorbs most of the calcium for bone formation from the calcite eggshell but the exact mechanisms of the resorption are unknown. The present study tested whether this process results in variable fractionation of the oxygen and carbon isotopes in shell calcium carbonate, which could provide a detailed insight into the temporal and spatial use of the eggshell by the developing embryo. Despite the uncertainty regarding changes in stable isotope composition of the eggshell across developmental stages or regions of the shell, eggshells are a popular resource for the analysis of historic and extant trophic relationships. To clarify how the stable isotope composition varies with embryonic development, the δ(13)C and δ(18)O content of the carbonate fraction in shells of black-headed gull (Larus ridibundus) eggs were sampled at four different stages of embryonic development and at five eggshell regions. No consistent relationship between the stable isotope composition of the eggshell and embryonic development, shell region or maculation was observed, although shell thickness decreased with development in all shell regions. By contrast, individual eggs differed significantly in isotope composition. These results establish that eggshells can be used to investigate a species' carbon and oxygen sources, regardless of the egg's developmental stage.

Assessment of left ventricular volumes, ejection fraction and mass. Comparison of model-based analysis of ECG-gated (99m)Tc-SPECT and ¹8F-FDG-PET.

AIM: We compared and delineated possible differences of model-based analysis of ECG-gated SPECT using (99m)Tc-sestamibi (Tc-SPECT) with ECG-gated ¹8F-fluorodeoxyglucose-PET (FDG-PET) for determination of end-diastolic (EDV) and end-systolic (ESV) cardiac volumes, left ventricular ejection fraction (LVEF), and myocardial mass (LVMM). PATIENTS, METHODS: 24 patients (21 men; age: 54±12years) with coronary artery disease underwent Tc-SPECT and FDG-PET imaging for evaluation of myocardial perfusion and viability. By using model-based analysis EDV, ESV, LVEF and LVMM were calculated from short axis images of both Tc-SPECT and FDG-PET. RESULTS: Left ventricular volumes by Tc-SPECT and FDG-PET were 176±60 ml and 181±59 ml for EDV, and 97±44 ml and 103±45 ml for ESV respectively, LVEF was 47±8% by Tc-SPECT and 45±9% by FDG-PET. The LVMM was 214±40 g (Tc-SPECT) and 202±43 g (FDG-PET) (all p = NS, paired t-test). A significant correlation was observed between Tc-SPECT and FDG-PET imaging for calculation of EDV (r = 0.93), ESV (r = 0.93), LVEF (r = 0.83) and LVMM (r = 0.72). CONCLUSION: ECG-gated Tc-SPECT and FDG-PET using two tracers with different characteristics (perfusion versus metabolism) showed close agreement concerning measurements of left ventricular volumes, contractile function and myocardial mass by using a model-based analysis.

Long-term outcome after thrombectomy in acute myocardial infarction.

BACKGROUND: Current data appear in favour of thrombectomy for ST-elevation myocardial infarction (STEMI). However, information on long-term outcome after thrombectomy is limited. We performed a retrospective long-term study to assess the risk of cardiac re-hospitalizations and survival after discharge from the index hospitalization for STEMI. METHODS: Patients originally randomized to percutaneous coronary intervention (PCI) with thrombectomy vs. standard PCI were included in a retrospective long-term observational study. The primary study endpoint was the combined risk for all-cause death or cardiac re-hospitalization after index discharge under optimal medical therapy. The cumulative number of cardiac hospitalization days and ventricular remodelling assessed by echocardiography and plasma biomarkers were secondary endpoints. RESULTS: Of 94 STEMI patients who had been randomized between 11/2000 and 03/2003, 89 patients consented to long-term follow-up. A total of 43 patients had been allocated to thrombectomy and 46 to standard primary PCI. The minimum follow-up time was 1115 days. There was a significantly lower risk for death or cardiac re-hospitalization for patients of the thrombectomy group (hazard ratio = 0.69, 95% CI: 0.49-0.98, P = 0.036). The incidence of recurrent myocardial infarction was not different (P = 0.343). No differences in cardiac remodelling were detected by echocardiography, with the exception that heart-type fatty acid binding protein at 53.2 +/- 17 months was lower in the thrombectomy group (P = 0.045). CONCLUSION: Thrombectomy in STEMI may decrease the long-term risk for death or cardiac re-hospitalization.

The inflammatory mediator oncostatin M induces stromal derived factor-1 in human adult cardiac cells.

Stromal derived factor 1 (SDF-1) is a CXC chemokine important in the homing process of stem cells to injured tissue. It has been implicated in healing and tissue repair. Growing evidence suggests that the glycoprotein-130 (gp130) ligand family is involved in repair processes in the heart. The aim of our study was to determine whether gp130 ligands could affect SDF-1 expression in cardiac cells. Human adult cardiac myocytes (HACMs) and fibroblasts (HACFs) were treated with gp130 ligands. Protein and mRNA levels of SDF-1 were determined using ELISA and RT-PCR, respectively. mRNA levels of SDF-1 were determined in human and mouse heart samples by RT-PCR. HACMs and HACFs constitutively express SDF-1, which was significantly up-regulated by the gp130 ligand oncostatin M (OSM). This effect was counteracted by a p38 inhibitor and to a lesser extent by a PI3K inhibitor. mRNA expression of SDF-1 in hearts of mice injected with OSM increased significantly. Levels of OSM and SDF-1 mRNA correlated significantly in human failing hearts. Our data, showing that OSM induces SDF-1 protein secretion in human cardiac cells in vitro and murine hearts in vivo, suggest that OSM via the induction of SDF-1 might play a key role in repair and tissue regeneration.

Methotrexate-induced myelopathy responsive to substitution of multiple folate metabolites.

Methotrexate (MTX)-associated myelopathy is a rare but serious subacute complication of MTX-based chemotherapy. We report the case of a woman with breast cancer and meningeal carcinomatosis who developed severe progressive myelopathy after four cycles of intrathecal MTX administration. We substituted high doses of the key metabolites of the methyl-transfer pathway: S-adenosylmethionine (SAM), 200 mg three times daily i.v.; folinate, 20 mg four times daily i.v.; cyanocobalamin, 100 microg once daily i.v.; and methionine, 5 g daily p.o. The patient's paraparesis improved rapidly thereafter, and magnetic resonance (MR) imaging showed resolution of the intramedullary lesions. Genetic analyses revealed homozygosity for the A allele of methylenetetrahydrofolate reductase (MTHFR) c.1298A>C (p.E429A), whereas other genetic variants of folate/methionine metabolism associated with MTX neurotoxicity were not present. Substitution with multiple folate metabolites may be a promising strategy for the treatment of MTX-induced neurotoxicity.

Echo Doppler parameters predict response to cardiac resynchronization therapy.

BACKGROUND: Cardiac resynchronization therapy (CRT) has been shown to reduce heart failure related morbidity and mortality. However, approximately 30% of patients do not respond to CRT. We investigated the usefulness of Echo Doppler parameters to predict reverse remodelling, functional improvement and mortality following CRT. MATERIALS AND METHODS: Our population consists of 200 consecutive heart failure patients evaluated for ventricular dyssynchrony by echocardiography between February 1999 and May 2007 who subsequently received CRT. Patients were reassessed for signs of reverse remodelling after a mean follow-up of 10 months. Information on vital status was obtained from local registration authorities. RESULTS: Three parameters significantly predicted reverse remodelling in the logistic regression analysis: the Q-to-E-wave-delay (QED) at a cutoff of 550 ms (odds ratio 4.5, P-value 0.001), the interventricular mechanical delay (IVMD) at a cutoff of 60 ms (odds ratio 2.4, P-value 0.02), and the aortic electromechanical delay (A-EMD) at a cutoff of 140 ms (odds ratio 2.9, P-value 0.004). Furthermore, the QED and the IVMD also predicted all-cause mortality (hazard ratio 0.36, P-value 0.02 and 0.21, P-value 0.004, respectively). Adjustment for confounders did not alter the results. CONCLUSIONS: The QED and IVMD predict reverse remodelling and survival following CRT. These parameters are easy to obtain, provide valuable prognostic information, and should thus be measured in CRT candidates evaluated by echocardiography.

Outcome after device implantation in chronic heart failure is dependent on concomitant medical treatment.

BACKGROUND: Device implantation in chronic heart failure (CHF) for cardiac resynchronization therapy (CRT) with or without implantable cardioverter/defibrillator (ICD) is an established treatment option for symptomatic patients under medical baseline therapy. Although recommended, the need for optimization of medical therapy was never proven. As in 'the real world', medical therapy is not always up-titrated to the desirable dosages; this provides the opportunity to evaluate the impact of optimizing medical therapy in patients who had received a device therapy with proven effectiveness. MATERIALS AND METHODS: This observational cohort study retrospectively assessed the 'real life'-effect of CRT compared with that of CRT/ICD therapy and the impact of concomitant pharmacotherapy on outcome. Outcome of patients with guideline recommended renin-angiotensin system inhibitor and ss-blocker dosages was compared with that of patients who failed to reach the desired dosages. Mean follow-up for the 205 CHF (95 CRT and 110 CRT/ICD) patients was 16.8 + or - 12.4 months. RESULTS: In the total study cohort, 83 (41%) reached the combined primary endpoint of all-cause death or cardiac hospitalization [CRT group: 25 (26%), CRT/ICD group: 58 (52.7%), P < 0.001]. Multiple cox regression analysis revealed non-optimized medical therapy at follow-up [HR = 2.080 (1.166-3.710), P = 0.013] and CRT/ICD vs. CRT [HR = 2.504 (1.550-4.045), P < 0.001] as significant predictors of the primary endpoint. CONCLUSION: Our data stress the importance of professional monitoring and titration of pharmacotherapy not only in medically treated CHF patients but also in patients under device therapy by a heart failure unit or a specialized cardiologist.

Vascular endothelial growth factor is induced by the inflammatory cytokines interleukin-6 and oncostatin m in human adipose tissue in vitro and in murine adipose tissue in vivo.

OBJECTIVES: It is believed that adipose tissue acts as an endocrine organ by producing inflammatory mediators and thereby contributes to the increased cardiovascular risk seen in obesity. A link between adipose tissue mass and angiogenesis has been suggested. Vascular endothelial growth factor (VEGF) seems to be implicated in this process. Members of the glycoprotein (gp)130 ligand family regulate VEGF expression in other cells. METHODS AND RESULTS: We used tissue explants as well as primary cultures of preadipocytes and adipocytes from human subcutaneous and visceral adipose tissue to investigate whether the gp130 ligands oncostatin M (OSM), interleukin-6 (IL-6), leukemia inhibitory factor (LIF), and cardiotrophin-1 (CT-1) regulate VEGF expression in human adipose tissue. Human subcutaneous and visceral adipose tissue responded to treatment with IL-6 and OSM with a significant increase in VEGF production. Human preadipocytes were isolated from subcutaneous and visceral adipose tissue. Adipocyte-differentiation was induced by hormone-supplementation. All cell types responded to IL-6 and OSM with a robust increase in VEGF protein production and a similar increase in VEGF-specific mRNA. Furthermore, IL-1beta synergistically enhanced the effect of OSM on VEGF production. AG-490, a JAK/STAT inhibitor, abolished the OSM-dependent VEGF induction almost completely. In mice, IL-6 and OSM increased serum levels of VEGF and VEGF mRNA and vessel density in adipose tissue. CONCLUSION: We speculate that the inflammatory cytokines IL-6 and OSM might support angiogenesis during adipose tissue growth by upregulating VEGF.

Macrophage colony stimulating factor expression in human cardiac cells is upregulated by tumor necrosis factor-alpha via an NF-kappaB dependent mechanism.

INTRODUCTION: Macrophage colony stimulating factor (M-CSF) is a key factor for monocyte and macrophage survival and proliferation. M-CSF has been implicated in cardiac healing and repair after myocardial infarction. METHODS AND RESULTS: We show by immunohistochemistry and Western blotting analysis that M-CSF protein is present in human heart tissue. Cultured human adult cardiac myocytes (HACM) and human adult cardiac fibroblasts (HACF) isolated from human myocardial tissue constitutively express M-CSF. When HACM and HACF were treated with tumor necrosis factor-alpha (TNF-alpha) M-CSF protein production and M-CSF mRNA expression, determined by ELISA or by using RT-PCR, respectively, was significantly increased. To determine a possible role of nuclear factor kappaB (NF-kappaB) and activating protein 1 (AP-1) in M-CSF regulation, blockers to both pathways and an adenovirus overexpressing a dominant negative (dn) form of IkappaB kinase 2 (IKK2) were used. Only the NF-kappaB blocker dimethylfumarate and the dn IKK2, but not januskinase inhibitor-1 (JNK-I), were able to block the TNF-alpha-induced increase in M-CSF production in these cells, suggesting that the induction of M-CSF through TNF-alpha is mainly dependent on the activation of the NF-kappaB pathway. The monocyte activation marker CD11b was significantly increased after incubating U937 cells with conditioned medium from HACM or HACF as determined by FACS analysis. CONCLUSIONS: Our in vitro data taken together with our immunohistochemistry data suggest that human cardiac cells constitutively express M-CSF. This expression of M-CSF in the human heart and its upregulation by TNF-alpha might contribute to monocyte and macrophage survival and differentiation.

Statins decrease TNF-alpha-induced osteoprotegerin production by endothelial cells and smooth muscle cells in vitro.

Recent reports have implicated osteoprotegerin (OPG) in cardiovascular disease processes. Endothelial and smooth muscle cells produce OPG and its expression in these cells is upregulated by inflammatory mediators. Statins, which besides their lipid lowering properties have various vasculoprotective effects, have been shown to regulate OPG expression in osteoblasts. We investigated whether statins affect the expression of OPG in human endothelial and smooth muscle cells. Using an ELISA we could demonstrate that statins reduce tumor necrosis factor-alpha (TNF-alpha)-induced OPG production in cultured human endothelial cells and smooth muscle cells. Atorvastatin also downregulated interleukin-1alpha (IL-1alpha)-induced OPG production in endothelial cells. A significant reduction of TNF-alpha-induced OPG was seen when statins were used in the nanomolar range. These results were confirmed at the level of specific mRNA expression by real-time-PCR. Using LDH leakage as a marker of cell damage we show that cell viability was not affected by statins at concentrations used in our study. The effect of statins on TNF-alpha-induced OPG production was reversed by mevalonate and geranyl-geranyl pyrophosphate at the level of protein production and at the level of mRNA expression, suggesting that it was brought about by inhibition of the mevalonic acid pathway and protein prenylation. Through our results we have added OPG to the list of molecules whose TNF-alpha-induced upregulation is counteracted by statins. If such an effect is also operative in the in vivo setting, one could postulate a role for statins in the modulation of cardiovascular disease processes possibly regulated by OPG.

[Urethral stricture rate after prostate cancer radiotherapy : Five-year data of a certified prostate cancer center]. / Harnröhrenstrikturrate nach Bestrahlung eines Prostatakarzinoms : 5-Jahres-Daten eines zertifizierten Prostatakarzinomzentrums.

BACKGROUND: A urethral stricture is a scar of the urethral epithelium which can cause obstructive voiding dysfunction with consequential damage of the upper urinary tract. Almost 45% of all strictures are iatrogenic; they develop in 2-9% of patients after radical prostatectomy, but can also occur after prostate cancer radiotherapy. This study provides 5­year data of a certified prostate cancer center (PKZ) in terms of urethral strictures. MATERIALS AND METHODS: Between 01/2008 and 12/2012 a total of 519 men were irradiated for prostate cancer (LDR and HDR brachytherapy as well as external beam radiation). The entire cohort was followed-up prospectively according to a standardized protocol (by type of irradiation). Short segment urethral strictures were treated by urethrotomy, recurrent and long segment stenosis with buccal mucosa urethroplasty. RESULTS: A total of 18 of 519 (3.4%) patients developed a urethral stricture post-therapeutically, which recurred in 66% of cases after the first operative treatment. The largest risk for developing a urethral stricture is attributed to the HDR brachytherapy (8.9%). CONCLUSION: Urethral strictures after prostate cancer radiotherapy should be diagnosed and treated in time for long-term preservation of renal function. The rate of radiogenic urethral strictures (3.4%) is equivalent to those after radical prostatectomy. Due to a high rate of recurrences, urethrotomy has a limited importance after irradiation.

Inflammatory cytokines interleukin-6 and oncostatin m induce plasminogen activator inhibitor-1 in human adipose tissue.

BACKGROUND: Adipose tissue is a prominent source of plasminogen activator inhibitor-1 (PAI-1), the primary physiological inhibitor of plasminogen activation. Increased PAI-1 expression acts as a cardiovascular risk factor, and plasma levels of PAI-1 strongly correlate with body mass index (BMI). Elevated serum levels of interleukin-6 (IL-6), an inflammatory cytokine and a member of the glycoprotein 130 (gp130) ligand family, are found in obese patients and might indicate low-grade systemic inflammation. Another gp130 ligand, oncostatin M (OSM), upregulates PAI-1 in cardiac myocytes, astrocytes, and endothelial cells. We used tissue explants and primary cultures of preadipocytes and adipocytes from human subcutaneous and visceral adipose tissue to investigate whether IL-6 and OSM affect PAI-1 expression in fat. METHODS AND RESULTS: Human subcutaneous and visceral adipose tissue responded to treatment with IL-6 and OSM with a significant increase in PAI-1 production. Human preadipocytes were isolated from subcutaneous and visceral adipose tissue. Adipocyte differentiation was induced by hormone supplementation. All cell types expressed receptors for IL-6 and OSM and produced up to 12-fold increased levels of PAI-1 protein and up to 9-fold increased levels of PAI-1 mRNA on stimulation with IL-6 and OSM. AG-490, a janus kinase/signal transducer and activator of transcription inhibitor, abolished the OSM-dependent PAI-1 induction almost completely. CONCLUSIONS: We have for the first time established a link between the gp130 ligands, the proinflammatory mediators IL-6 and OSM, and the expression of PAI-1 in human adipose tissue. Thus, we speculate that IL-6 and OSM, by upregulating PAI-1 in adipose tissue, can contribute to the increased cardiovascular risk of obese patients.

The complement component C5a induces the expression of plasminogen activator inhibitor-1 in human macrophages via NF-kappaB activation.

BACKGROUND: Atherosclerosis is considered to be a chronic inflammatory disorder. Activation of the complement cascade is a major aspect of chronic inflammatory diseases. Complement components were identified in atherosclerotic plaques, and a correlation between adverse events and C5a plasma levels was found. These findings support the notion that complement activation contributes to development and progression of atherosclerotic lesions. OBJECTIVES: We investigated whether complement components C3a and C5a regulate plasminogen activator inhibitor (PAI-1) in human macrophages. METHODS: Human monocyte-derived macrophages (MDM) and human plaque macrophages were cultured and incubated with the complement component C5a. RESULTS: C5a increased PAI-1 up to 11-fold in human MDM and up to 2.7-fold in human plaque macrophages. These results were confirmed at the mRNA level using real time-polymerase chain reaction. Pertussis toxin or anti-C5aR/CD88 antibody completely abolished the effect of recombinant human C5a on PAI-1 production, suggesting a role of the C5a receptor. Experiments with antitumor necrosis factor (TNF)-alpha antibodies and tiron showed that the effect of C5a was not mediated by TNF-alpha or oxidative burst. Furthermore C5a induced NF-kappaB binding to the cis element in human macrophages and the C5a-induced increase in PAI-1 was completely abolished by an NF-kappaB inhibitor. CONCLUSIONS: We conclude that C5a upregulates PAI-1 in macrophages via NF-kappaB activation. We hypothesize that - if operative in vivo- this effect could favor thrombus development and thrombus stabilization in the lesion area. On the other hand one could speculate that C5a-induced upregulation of PAI-1 in plaque macrophages could act as a defense mechanism against plaque destabilization and rupture.

No evidence for a direct role of Helicobacter pylori and Mycoplasma pneumoniae in carotid artery atherosclerosis.

BACKGROUND: That infections with certain pathogens, by initiating an inflammatory response, may contribute to the development of atherosclerosis is suggested by clinical and experimental evidence. AIM: To analyse atherosclerotic plaques of the carotid artery, samples of apparently healthy greater saphenous veins and circulating leucocytes from the same individual patients for the presence of Helicobacter pylori and Mycoplasma pneumoniae. METHODS: Samples from 36 patients undergoing carotid endarterectomy for symptomatic carotid artery stenosis were analysed by polymerase chain reaction for the presence of DNA specific for H. pylori and M. pneumoniae. IgG antibody titres against H. pylori and M pneumoniae and plasma levels of soluble E-selectin, soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 were determined. RESULTS: M. pneumoniae-specific DNA was detected in the atherosclerotic plaques of 13 of 36 (36.1%) patients, in the saphenous veins of 9 of 36 (25%) patients and in the leucocytes of 27 of 36 (75%) patients. No salient association was observed between the presence of M. pneumoniae-specific DNA in leucocytes and atherosclerotic plaques or veins. A marked correlation between the presence of M. pneumoniae in the respective specimens and the studied inflammatory markers or the presence of anti-M. pneumoniae antibodies was not observed. H. pylori-specific DNA could not be detected in the specimens tested. CONCLUSIONS: The absence of H. pylori and the random distribution of M. pneumoniae in tissue samples obtained from patients with symptomatic carotid artery stenosis do not support a role for these pathogens in the development of atherosclerosis due to a direct interaction of the bacteria with the vasculature.