Circulating transforming growth factor beta 1 and coronary artery disease

Evaluation of Fibrosis Markers as a Potential Method for Diagnosing Non-Obstructive Coronary Artery Disease in Patients with Stable Coronary Artery Disease

Aim. To study the levels of fibrosis markers in patients with stable coronary artery disease (CAD) and various types of coronary artery (CA) lesions (obstructive and non-obstructive), to identify possible differences for diagnosing the types of coronary obstruction.

Material and methods. The observational study included three groups of patients: with non-obstructive (main group, coronary artery stenosis <50%; n=20) and obstructive (comparison group, hemodynamically significant coronary artery stenosis according to the results of coronary angiography; n=20) CAD and healthy volunteers (control group; n=40). Transforming growth factor beta 1 (TGF-β1) and matrix metalloproteinase 9 (MMP-9) levels were measured in plasma by enzyme immunoassay. According to the results of echocardiography, all patients included in the study were divided into four groups depending on the type of myocardial remodeling.

Results. TGF-β1 levels were significantly higher in patients with obstructive CAD (p=0.008) than in patients with non-obstructive CAD and healthy volunteers (p <0.001). There were no significant differences between the main and control groups (p>0.05). There were no statistically significant differences in TGF-β1 levels depending on the type of left ventricular remodeling (p=0.139). The maximum level of MMP-9 was in the group with obstructive coronary disease and significantly differed from the main group (p <0.001) and the control group (p=0.04).

Conclusio. The maximum levels of TGF-β1 and MMP-9 were found in the group with obstructive coronary artery disease. The levels of these biomarkers in the main group were statistically different from the values obtained in the control group. Thus, considering the pathogenesis of the development of non-obstructive CAD, the use of fibrosis markers TGF-β1 and MMP-9 may be promising for diagnosing the severity of CA obstruction.

Insights into bone morphogenetic proteins in cardiovascular diseases

Bone morphogenetic proteins (BMPs) are secretory proteins belonging to the transforming growth factor-β (TGF-β) superfamily. These proteins play important roles in embryogenesis, bone morphogenesis, blood vessel remodeling and the development of various organs. In recent years, as research has progressed, BMPs have been found to be closely related to cardiovascular diseases, especially atherosclerosis, vascular calcification, cardiac remodeling, pulmonary arterial hypertension (PAH) and hereditary hemorrhagic telangiectasia (HHT). In this review, we summarized the potential roles and related mechanisms of the BMP family in the cardiovascular system and focused on atherosclerosis and PAH.

Stable CAD patients show higher levels of platelet-borne TGF-β1 associated with a superior pro-inflammatory state than the pro-aggregatory status; Evidence highlighting the importance of platelet-derived TGF-β1 in atherosclerosis

Activated platelets are involved in the atherogenic stage of atherosclerosis, while they can also progress it to atherothrombosis which may cause an ischemic state and organ failure. In general, coronary artery disease (CAD) is considered as common and severe clinical consequence of atherosclerosis, manifesting as a chronic inflammatory condition with the release of platelet mediators, among which the importance of platelet-borne TGF-β1 is not yet well understood. Hence, for the first time, this study aimed to examine platelet level of TGF-β1 (latent/mature) in CAD-patients and its association with the expression of platelet pro-inflammatory molecules. Platelet from stable CAD-patients candidate for CABG and healthy controls were subjected to flowcytometry analysis to evaluate P-selectin and CD40L expressions and PAC-1 binding. Platelet-borne and soluble TGF-β1, both mature/active and latent forms were also examined with western blotting. Higher expression levels of P-selectin and CD40L in patients with CAD than in controls were associated with comparable levels of PAC-1 binding in both groups. Platelet TGF-β1 levels were also significantly higher in patients, while their platelets showed clear bands of mature TGF-β1 that were barely visible in healthy individuals. Soluble TGF-β1 was also higher in patients. Significant correlations between mature/active TGF-β1 and platelet pro-inflammatory markers (P-selectin and CD40L) as well as common indicators of inflammation (CRP and ESR) were observed in CAD patients. In this study, given the insignificant changes in pro-aggregatory potentials in stable CAD, the pro-inflammatory state of platelets may be more involved in disease development and progression. Direct correlations between active platelet-borne TGF-β1 and pro-inflammatory markers with its presence in CAD-patients, which was almost absent in the platelets of healthy individuals, may also underscore the significant contribution of platelet-borne TGF-β1 to the pathogenesis of the disease.

ROLE OF THE TRANSFORMING GROWTH FACTOR β1 IN THE GENESIS OF ARTERIAL HYPERTENSION AND ITS COMPLICATIONS

Transforming growth factor beta 1 (TGFβ1) is an actively studied cytokine with rather contradictory effects. The article systematizes and summarizes the scientific data on TGFβ1 and its role in the development and progression of arterial hypertension, with an emphasis on arterial stiffness.

The role of bone morphogenetic protein signaling in vascular calcification

Vascular calcification is associated with atherosclerosis, chronic kidney disease, and diabetes, and results from processes resembling endochondral or intramembranous ossification, or from processes that are distinct from ossification. Bone morphogenetic proteins (BMP), as well as other ligands, receptors, and regulators of the transforming growth factor beta (TGFβ) family regulate vascular and valvular calcification by modulating the phenotypic plasticity of multipotent progenitor lineages associated with the vasculature or valves. While osteogenic ligands BMP2 and BMP4 appear to be both markers and drivers of vascular calcification, particularly in atherosclerosis, BMP7 may serve to protect against calcification in chronic kidney disease. BMP signaling regulators such as matrix Gla protein and BMP-binding endothelial regulator protein (BMPER) play protective roles in vascular calcification. The effects of BMP signaling molecules in vascular calcification are context-dependent, tissue-dependent, and cell-type specific. Here we review the current knowledge on mechanisms by which BMP signaling regulates vascular calcification and the potential therapeutic implications.

Vitamin D Supplementation Ameliorates Metabolic Dysfunction in Patients with PCOS: A SystematicReview of RCTs and Insight into the Underlying Mechanism

OBJECTIVE

Evidence suggests that vitamin D deficiency correlated with metabolic disorders in women with polycystic ovary syndrome (PCOS). We conducted this systematic review and meta-analysis to evaluate the impact of vitamin D supplementation alone on glucose, lipid, and androgen parameters and inflammation biomarkers in women with PCOS.

METHODS

Literature research was conducted in Pubmed, Embase, Web of Science, Clinical Trials, and Cochrane Library to identify relevant randomized controlled trials (RCTs) up to March 2020. The effect of vitamin D supplementation alone on women with PCOS was compared with administration of placebo. The systematic review and meta-analysis protocol was registered in the International Prospective Register of Systematic Reviews (Prospero) as number CRD42020157444.

RESULTS

Thirteen randomized controlled trials with 824 patients in total were included. Serum FPG, fasting insulin, HOMA-IR, and VLDL-C were significantly decreased in the vitamin D group versus placebo. Vitamin D supplementation group also showed a significantly elevated level of QUICKI. No significant impact was seen on serum triglyceride, total-C, LDL-C, HDL-C, total testosterone, DHEAS, SHBG, or hs-CRP. Subgroup analysis demonstrated that oral vitamin D intake had significantly decreased serum triglyceride and total-C level in women with PCOS who have vitamin D deficiency (serum vitamin D < 20 ng/ml).

CONCLUSION

The findings of the present meta-analysis indicate that vitamin D supplementation exerted favorable effects among women with PCOS on glucose metabolism and lipid metabolism, especially in vitamin D deficient women, but had no significant effect on the androgenic profile or inflammation status.

Transforming Growth Factor Beta 1 and Vascular Risk in Alcoholics

INTRODUCTION

Transforming growth factor beta-1 (TGF-β1) is a pleiotropic cytokine. Its relationship with atherosclerosis is debatable, protective or deleterious effects have been described. Alcoholics are at increased vascular risk. Although TGF-β1 is increased in alcoholics, its role on vascular risk factors has not been analyzed. This is the objective of this study.

PATIENTS AND METHODS

79 heavy alcoholics and 34 controls were included. Calcium deposition in the aortic arch was assessed in the plain thorax X-ray film. Ankle-brachial index was recorded in 48 patients. All the patients underwent complete laboratory evaluation, including serum levels of TGF-β1, tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-6, and interferon-γ (IFN-γ).We analyzed the relationships between TGF-β1 and vascular risk factors by both univariate (parametric or non parametric tests), or multivariate analysis to discern on which variables TGF-β1 levels depend.

RESULTS

Serum TGF-β1 levels were higher among patients (t = 2.73; P = 0.008), but no differences exist among cirrhotics (17246 ± 11,021 pg/mL) and non-cirrhotics (21,340 ± 12,442 pg/mL). TGF-β1 showed significant correlations with total cholesterol (r = 0.28; P = 0.017) and HDL- cholesterol (r = 0.25; P = 0.042), and inverse correlations with body mass index (BMI; ρ = -0.37; P = 0.004), IL-4 (ρ = -0.31; P = 0.009), INF-γ (ρ = -0.28; P = 0.001), and IL-6 (ρ = -0.38; P = 0.001). By multivariate analysis, only BMI, IL-6 and HDL-cholesterol showed independent relationships with TGF-β1. No relationships were observed with ankle-brachial index or calcium in the aortic arch, hypertension, diabetes, left ventricular hypertrophy or atrial fibrillation.

CONCLUSION

TGF-β1 levels are increased in alcoholics, but are unrelated to vessel wall calcification or arterial stiffness.

TGFβ, smooth muscle cells and coronary artery disease: a review

Excessive vascular smooth muscle cell (SMC) proliferation, migration and extracellular matrix (ECM) synthesis are key events in the development of intimal hyperplasia, a pathophysiological response to acute or chronic sources of vascular damage that can lead to occlusive narrowing of the vessel lumen. Atherosclerosis, the primary cause of coronary artery disease, is characterised by chronic vascular inflammation and dyslipidemia, while revascularisation surgeries such as coronary stenting and bypass grafting represent acute forms of vascular injury. Gene knockouts of transforming growth factor-beta (TGFβ), its receptors and downstream signalling proteins have demonstrated the importance of this pleiotropic cytokine during vasculogenesis and in the maintenance of vascular homeostasis. Dysregulated TGFβ signalling is a hallmark of many vascular diseases, and has been associated with the induction of pathological vascular cell phenotypes, fibrosis and ECM remodelling. Here we present an overview of TGFβ signalling in SMCs, highlighting the ways in which this multifaceted cytokine regulates SMC behaviour and phenotype in cardiovascular diseases driven by intimal hyperplasia.

Transforming Growth Factor β1 (TGF-β1) Appears to Promote Coronary Artery Disease by Upregulating Sphingosine Kinase 1 (SPHK1) and Further Upregulating Its Downstream TIMP-1

BACKGROUND Transforming growth factor (TGF)-β1 is involved in the pathogenesis of coronary artery disease (CAD), but the mechanism of its action remains unclear. Our study aimed to investigate the role of TGF-β1 in CAD and to explore the possible mechanisms. MATERIAL AND METHODS A total of 60 CAD patients and 54 healthy people were included in this study. Blood samples were drawn from each participant to prepare serum. ELISA was utilized to measure serum level of TGF-β1. TGF-β1 expression vector, TGF-β1 siRNA, and TIMP-1 siRNA were transfected into human primary coronary artery endothelial cell (HCAEC) line cells, and expression of TGF-β1 sphingosine kinase 1 (SPHK1) and TIMP metallopeptidase inhibitor 1 (TIMP-1) was detected by Western blot. Cell apoptosis was detected by MTT assay. RESULTS Serum level of TGF-β1 was specifically higher in patients with CAD than in healthy controls. Serum levels of active TGF-β1 can be used to effectively distinguish CAD patients from healthy controls. TGF-β1 overexpression promoted the apoptosis of HCAEC and TGF-β1 siRNA silencing inhibited the apoptosis of HCAEC. TGF-β1 overexpression also promoted the expression of SPHK1 and TIMP-1. SPHK1 overexpression upregulated TIMP-1 but it showed no significant effects on TGF-β1. TIMP-1 overexpression showed no significant effects on TGF-β1 or SPHK1. SPHK1 inhibitor and TIMP-1 silencing reduced the enhancing effects of TGF-β1 overexpression on cell apoptosis. CONCLUSIONS TGF-β1 appears to promote CAD through the induction of cell apoptosis by upregulating SPHK1 expression and further upregulating its downstream TIMP-1.

The role of lnc-DC long non-coding RNA and SOCS1 in the regulation of STAT3 in coronary artery disease and type 2 diabetes mellitus

AIMS

Coronary artery disease (CAD) can be classified as an inflammatory disease, which affected by type 2 diabetes mellitus (T2DM). Elevated levels of many inflammatory molecules were found in the serum of patients with CAD. STAT3 molecule as a transcription factor plays an important role in the cytokines expression. Here, we examined the expression levels of STAT3 and its important regulatory genes lnc-DC and SOCS1, in patients with CAD and T2DM.

METHODS

Blood samples were obtained from 37 CAD+ and 36 CAD- patients. These patients were enrolled in this study based on angiography findings and categorized based on T2DM status. The expression levels of STAT3, lnc-DC and SOCS1 genes were examined with Real time PCR method.

RESULTS

A significant increase was observed in expression of STAT3 and lnc-DC genes but not SOCS1 in CAD+ versus CAD- patients. These results replicated partially in some groups categorized based on T2DM and CAD status. However, severity of CAD had no effect on expressions of these genes. Moreover, we found some significant correlations between expressions of lnc-DC with SOCS1 and STAT3, which confirmed by in silico analysis.

CONCLUSION

Our results shed further light to the inflammatory aspects of CAD and T2DM with emphasis to JAK/STAT pathway and the regulatory role of long non-coding RNAs in the physiopathology of these diseases.

New methodologies to accurately assess circulating active transforming growth factor-β1 levels: implications for evaluating heart failure and the impact of left ventricular assist devices

Transforming growth factor-β1 (TGF-β1) has been used as a biomarker in disorders associated with pathologic fibrosis. However, plasma TGF-β1 assessment is confounded by the significant variation in reported normal values, likely reflecting variable release of the large pool of platelet TGF-β1 after blood drawing. Moreover, current assays measure only total TGF-β1, which is dominated by the latent form of TGF-β1 rather than the biologically active form. To address these challenges, we developed methodologies to prevent ex vivo release of TGF-β1 and to quantify active TGF-β1. We then used these techniques to measure TGF-β1 in healthy controls and patients with heart failure (HF) before and after insertion of left ventricular assist devices (LVAD). Total plasma TGF-β1 was 1.0 ± 0.60 ng/mL in controls and 3.76 ± 1.55 ng/mL in subjects with HF (P < 0.001), rising to 5.2 ± 2.3 ng/mL following LVAD placement (P = 0.006). These results were paralleled by the active TGF-β1 values; controls had 3-16 pg/mL active TGF-β1, whereas levels were 2.7-fold higher in patients with HF before, and 4.2-fold higher after, LVAD implantation. Total TGF-β1 correlated with levels of the platelet-derived protein thrombospondin-1 (r = 0.87; P < 0.001), suggesting that plasma TGF-β1 may serve as a surrogate indicator of in vivo platelet activation. von Willebrand factor high molecular weight multimers correlated inversely with TGF-β1 levels (r = -0.63; P = 0.023), suggesting a role for shear forces in loss of these multimers and platelet activation. In conclusion, accurate assessment of circulating TGF-β1 may provide a valuable biomarker for in vivo platelet activation and thrombotic disorders.

Genomic correlates of glatiramer acetate adverse cardiovascular effects lead to a novel locus mediating coronary risk

Glatiramer acetate is used therapeutically in multiple sclerosis but also known for adverse effects including elevated coronary artery disease (CAD) risk. The mechanisms underlying the cardiovascular side effects of the medication are unclear. Here, we made use of the chromosomal variation in the genes that are known to be affected by glatiramer treatment. Focusing on genes and gene products reported by drug-gene interaction database to interact with glatiramer acetate we explored a large meta-analysis on CAD genome-wide association studies aiming firstly, to investigate whether variants in these genes also affect cardiovascular risk and secondly, to identify new CAD risk genes. We traced association signals in a 200-kb region around genomic positions of genes interacting with glatiramer in up to 60 801 CAD cases and 123 504 controls. We validated the identified association in additional 21 934 CAD cases and 76 087 controls. We identified three new CAD risk alleles within the TGFB1 region on chromosome 19 that independently affect CAD risk. The lead SNP rs12459996 was genome-wide significantly associated with CAD in the extended meta-analysis (odds ratio 1.09, p = 1.58×10⁻¹²). The other two SNPs at the locus were not in linkage disequilibrium with the lead SNP and by a conditional analysis showed p-values of 4.05 × 10⁻¹⁰ and 2.21 × 10⁻⁶. Thus, studying genes reported to interact with glatiramer acetate we identified genetic variants that concordantly with the drug increase the risk of CAD. Of these, TGFB1 displayed signal for association. Indeed, the gene has been associated with CAD previously in both in vivo and in vitro studies. Here we establish genome-wide significant association with CAD in large human samples.

Genome-Wide Linkage Analysis of Large Multiple Multigenerational Families Identifies Novel Genetic Loci for Coronary Artery Disease

Coronary artery disease (CAD) is the leading cause of death, and genetic factors contribute significantly to risk of CAD. This study aims to identify new CAD genetic loci through a large-scale linkage analysis of 24 large and multigenerational families with 433 family members (GeneQuest II). All family members were genotyped with markers spaced by every 10 cM and a model-free nonparametric linkage (NPL-all) analysis was carried out. Two highly significant CAD loci were identified on chromosome 17q21.2 (NPL score of 6.20) and 7p22.2 (NPL score of 5.19). We also identified four loci with significant NPL scores between 4.09 and 4.99 on 2q33.3, 3q29, 5q13.2 and 9q22.33. Similar analyses in individual families confirmed the six significant CAD loci and identified seven new highly significant linkages on 9p24.2, 9q34.2, 12q13.13, 15q26.1, 17q22, 20p12.3, and 22q12.1, and two significant loci on 2q11.2 and 11q14.1. Two loci on 3q29 and 9q22.33 were also successfully replicated in our previous linkage analysis of 428 nuclear families. Moreover, two published risk variants, SNP rs46522 in UBE2Z and SNP rs6725887 in WDR12 by GWAS, were found within the 17q21.2 and 2q33.3 loci. These studies lay a foundation for future identification of causative variants and genes for CAD.

NADPH oxidase 4 regulates vascular inflammation in aging and atherosclerosis

We recently reported that increased NADPH oxidase 4 (NOX4) expression and activity during aging results in enhanced cellular and mitochondrial oxidative stress, vascular inflammation, dysfunction, and atherosclerosis. The goal of the present study was to elucidate the molecular mechanism(s) for these effects and determine the importance of NOX4 modulation of proinflammatory gene expression in mouse vascular smooth muscle cells (VSMCs). A novel peptide-mediated siRNA transfection approach was used to inhibit Nox4 expression with minimal cellular toxicity. Using melittin-derived peptide p5RHH, we achieved significantly higher transfection efficiency (92% vs. 85% with Lipofectamine) and decreased toxicity (p<0.001 vs. Lipofectamine in MTT and p<0.0001 vs. Lipofectamine in LDH assays) in VSMCs. TGFβ1 significantly upregulates Nox4 mRNA (p<0.01) and protein (p<0.01) expression in VSMCs. p5RHH-mediated Nox4 siRNA transfection greatly attenuated TGFβ1-induced upregulation of Nox4 mRNA (p<0.01) and protein (p<0.0001) levels and decreased hydrogen peroxide production (p<0.0001). Expression of pro-inflammatory genes Ccl2, Ccl5, Il6, and Vcam1 was significantly upregulated in VSMCs in several settings cells isolated from aged vs. young wild-type mice, in atherosclerotic arteries of Apoe^-/- mice, and atherosclerotic human carotid arteries and correlated with NOX4 expression. p5RHH-mediated Nox4 siRNA transfection significantly attenuated the expression of these pro-inflammatory genes in TGFβ1-treated mouse VSMCs, with the highest degree of inhibition in the expression of Il6. p5RHH peptide-mediated knockdown of TGFβ-activated kinase 1 (TAK1, also known as Map3k7), Jun, and Rela, but not Nfkb2, downregulated TGFβ1-induced Nox4 expression in VSMCs. Together, these data demonstrate that increased expression and activation of NOX4, which might result from increased TGFβ1 levels seen during aging, induces a proinflammatory phenotype in VSMCs, enhancing atherosclerosis.

The association of functional polymorphisms in genes encoding growth factors for endothelial cells and smooth muscle cells with the severity of coronary artery disease

Background

Despite the important roles of vascular smooth muscle cells and endothelial cells in atherosclerotic lesion formation, data regarding the associations of functional polymorphisms in the genes encoding growth factors with the severity of coronary artery disease (CAD) are lacking. The aim of the present study is to analyze the relationships between functional polymorphisms in genes encoding basic fibroblast growth factor (bFGF, FGF2), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1), platelet derived growth factor-B (PDGFB), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor A (VEGF-A) and the severity of coronary atherosclerosis in patients with stable CAD undergoing their first coronary angiography.

Methods

In total, 319 patients with stable CAD who underwent their first coronary angiography at the Silesian Centre for Heart Diseases in Zabrze, Poland were included in the analysis. CAD burden was assessed using the Gensini score. The TaqMan method was used for genotyping of selected functional polymorphisms in the FGF2, PDGFB, TGFB1, IGF1 and VEGFA genes, while rs4444903 in the EGF gene was genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The associations between the selected polymorphisms and the Gensini were calculated both for the whole cohort and for a subgroup of patients without previous myocardial infarction (MI).

Results

There were no differences in the distribution of the Gensini score between the genotypes of the analyzed polymorphisms in FGF2, EGF, IGF1, PDFGB, and TGFB1 in the whole cohort and in the subgroup of patients without previous MI. The Gensini score for VEGFA rs699947 single-nucleotide polymorphism (SNP) in patients without previous myocardial infarction, after correction for multiple testing, was highest in patients with the A/A genotype, lower in heterozygotes and lowest in patients with the C/C genotype, (p value for trend = 0.013, false discovery rate (FDR) = 0.02). After adjustment for clinical variables, and correction for multiple comparisons the association between the VEGFA genotype and Gensini score remained only nominally significant (p = 0.04, FDR = 0.19) under the dominant genetic model in patients without previous MI.

Conclusions

We were unable to find strong association between analyzed polymorphisms in growth factors and the severity of coronary artery disease, although there was a trend toward association between rs699947 and the severity of CAD in patients without previous MI.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-016-0402-4) contains supplementary material, which is available to authorized users.

Association of Soluble Fibrinogen-like Protein 2 with the Severity of Coronary Artery Disease

Objective The purpose of this study was to investigate the relationship between circulating soluble fibrinogen-like protein 2 (sFGL2) concentrations and the severity of coronary artery disease (CAD) in patients who underwent first-time angiography for suspected CAD. Methods Serum sFGL2 concentrations were measured in 102 consecutive patients by an enzyme-linked immunosorbent assay (ELISA). The number of circulating CD4(+)CD25(+)CD127(low) T regulatory cells (Tregs) was determined by flow cytometry and effecter cytokines, including transforming growth factor-β1 and interleukin-10 (IL-10), were also evaluated by an ELISA. Associations between sFGL2 and Tregs with angiographic indexes of the severity of CAD (i.e., number of diseased vessels and the modified Gensini score) were estimated. Results The sFGL2 levels in patients with angiographically confirmed CAD were significantly lower than those in patients with normal coronary arteries (26.95±8.53 vs. 9.88±5.46 ng/mL, p<0.001). Significant correlations were observed between the serum sFGL2 level and number of diseased vessels (r=-0.860, p<0.001) and modified Gensini score (r=-0.833, p<0.001). Using a multivariate analysis, the serum sFGL2 level was independently associated with the presence and severity of CAD. Conclusion The serum sFGL2 levels are significantly lower in the presence of CAD and correlate with the severity of the disease. Further clinical studies are needed to confirm the use of sFGL2 as a biomarker for the detection and extent of CAD.

Platelet expression of transforming growth factor beta 1 is enhanced and associated with cardiovascular prognosis in patients with acute coronary syndrome

BACKGROUND

Functional recovery and prognosis after acute coronary syndromes (ACS) are mainly driven by the extent of reperfusion injury and myocardial repair mechanisms. Transforming growth factor-beta 1 (TGF-β1) is critically involved in cardiac injury, repair and remodeling. In this study, we investigated the prognostic role of platelet TGF-β1 surface expression and circulating TGF-β1 levels in patients with coronary artery disease (CAD).

METHODS AND RESULTS

Expression of TGF-β1 in platelets and circulating TGF-β1 levels were investigated by flow cytometry and ELISA, respectively, among patients with ACS and stable CAD undergoing percutaneous coronary intervention (PCI). In a cohort study, platelet and circulating TGF-β1 was measured in 299 patients with symptomatic CAD (stable CAD = 145, ACS = 154) at the time of PCI. The primary combined endpoint was defined as death and/or STEMI during 12-month follow-up. Platelets expressed TGF-β1 and circulating TGF-β1 showed a weak, but significant negative correlation. TGF-β1 surface expression was significantly elevated on platelets in ACS patients compared to patients with stable CAD (median MFI 13.4 vs. median MFI 11.7, p = 0.003). During follow-up, lower platelet expression of TGF-β1 was associated with all-cause mortality (median MFI 11.0 vs. median MFI 13.9, p = 0.011) as well as for the combined endpoint of death and/or STEMI, (median MFI 10.8 vs. median MFI 13.9, p = 0.006). In multivariate analysis platelet TGF-β1 expression was independently associated with the combined primary endpoint in the overall cohort (Hazard Ratio 0.31, 95% Confidence Interval 0.11-0.89, p = 0.029) and was strongly associated with prognosis in ACS patients. There was no significant association of circulating TGF-β1 levels neither with the presence of ACS nor the occurrence of the primary endpoint.

CONCLUSION

These findings highlight a potential role of platelet expressed TGF-β1 in ACS and indicate a prognostic value of TGF-β1 on clinical outcomes in patients with acute coronary syndromes. Large scale studies are warranted to further evaluate the regulatory mechanisms of platelet TGF-β1 expression- and its prognostic impact in CAD.

Clinical outcome in patients with acute coronary syndrome and outward remodeling is associated with a predominant inflammatory response

BACKGROUND

Pro-inflammatory molecules and low-density lipoproteins play essential roles in the atherosclerosis. The aim of our study was to establish an association among the cytokines secreted by peripheral blood mononuclear cells and the serum concentration in patients with unstable angina and coronary outward remodeling before and after percutaneous coronary intervention. The clinical and coronary responses were evaluated 6 months after the procedure.

FINDINGS

Twenty-two patients with unstable angina were evaluated prior to after percutaneous coronary intervention and 6 months after procedure by coronary intravascular ultrasound. Eleven of the patients had recurrent angina, while 9 presented restenosis and an increase in the percentage of total plaque area. These 11 patients displayed higher levels of C-reactive protein than those without coronary events (1.27 vs. 0.43 mg/dl, respectively; p = 0.029) and a tendency to increase levels of interleukin (IL)-8 and transforming growth factor-β1, but lower levels of IL-10 (52.09 vs. 141.5 pg/ml, respectively; p = 0.035). Activated peripheral blood mononuclear cells from patients with restenosis presented higher levels of proliferation, CD86 expression and higher IL-1, and increased IL-10 compared to those in patients without restenosis.

CONCLUSIONS

Patients with unstable angina and coronary outward remodeling who displayed a pro-inflammatory response experienced recurrent coronary events and an increased percentage of total plaque area. In contrast, better outcomes were observed in patients with anti-inflammatory responses. This response could be secondary to low-density lipoproteins.

N-Acetylcysteine effects on transforming growth factor-β and tumor necrosis factor-α serum levels as pro-fibrotic and inflammatory biomarkers in patients following ST-segment elevation myocardial infarction

Background and Aims

Ischemia following acute myocardial infarction (AMI) increases the level of pro-fibrotic and inflammatory cytokines, including transforming growth factor (TGF)-β and tumor necrosis factor (TNF)-α. N-acetylcysteine (NAC) has therapeutic benefits in the management of patients with AMI. To the best of our knowledge, this is the first study that has evaluated the effect of NAC on TNF-α and TGF-β levels in patients with AMI.

Methods

Following confirmation of AMI, 88 patients were randomly administered NAC 600 mg (Fluimucil^®, Zambon, Ticino, Switzerland) or placebo orally twice daily for 3 days. For quantification of TGF-β and TNF-α serum levels after 24 and 72 h of NAC or placebo administration, peripheral venous blood (10 mL) samples were collected at these time points.

Results

Comparisons between levels of TGF-β and TNF-α after 24 and 72 h within the NAC or placebo groups revealed that there was not any significant difference except for TGF-β levels in the placebo group, which increased significantly over time (p = 0.042). Significant relationships existed between patients’ ejection fraction (p = 0.005) and TGF-β levels.

Conclusions

Receiving NAC could prevent TGF-β levels from increasing after 72 h as compared with not receiving NAC. As TGF-β had strong correlations with the ejection fraction, its antagonism seems to be important in the prevention of remodeling.

Inflammation's Association with Metabolic Profiles before and after a Twelve-Week Clinical Trial in Drug-Naïve Patients with Bipolar II Disorder

Inflammation is thought to be involved in the pathophysiology of bipolar disorder (BP) and metabolic syndrome. Prior studies evaluated the association between metabolic profiles and cytokines only during certain mood states instead of their changes during treatment. We enrolled drug-naïve patients with BP-II and investigated the correlation between changes in mood symptoms and metabolic indices with changes in plasma cytokine levels after 12 weeks of pharmacological treatment. Drug-naïve patients (n = 117) diagnosed with BP-II according to DSM-IV criteria were recruited. Metabolic profiles (cholesterol, triglyceride, HbA1C, fasting serum glucose, body mass index (BMI) and plasma cytokines (TNF-α, CRP, IL-6, and TGF-β) were measured at baseline and 2, 8, and 12 weeks post-treatment. To adjust within-subject dependence over repeated assessments, multiple linear regressions with generalized estimating equation methods were used. Seventy-six (65.0%) patients completed the intervention. Changes in plasma CRP were significantly associated with changes in BMI (P = 1.7E-7) and triglyceride (P = 0.005) levels. Changes in plasma TGF-β1 were significantly associated with changes in BMI (P = 8.2E-6), cholesterol (P = 0.004), and triglyceride (P = 0.006) levels. However, changes in plasma TNF-α and IL-6 were not associated with changes in any of the metabolic indices. Changes in Hamilton Depression Rating Scale scores were significantly associated with changes in IL-6 (P = 0.003) levels; changes in Young Mania Rating Scale scores were significantly associated with changes in CRP (P = 0.006) and TNF-α (P = 0.039) levels. Plasma CRP and TGF-β1 levels were positively correlated with several metabolic indices in BP-II after 12 weeks of pharmacological intervention. We also hypothesize that clinical symptoms are correlated with certain cytokines. These new findings might be important evidence that inflammation is the pathophysiology of clinical symptoms and metabolic disturbance in BP-II.

Trial Registration

ClinicalTrials.gov NCT01188148.

The T29C polymorphism of the transforming growth factor-β1 (TGF-β1) gene is associated with genetic susceptibility to acute coronary syndrome in Mexican patients

Inflammation plays an essential role in the development and progression of atherosclerotic lesions, and plaque disruption. The TGF-β1 plays an important role in the anti-inflammatory process. The aim of the present study was to evaluate the role of TGF-β1 gene polymorphisms as susceptibility markers for acute coronary syndrome (ACS). Two polymorphisms (TGF-β -509T>C and TGF-β T29C) of the TGF-β gene were analyzed by 5' exonuclease TaqMan genotyping assays in a group of 426 patients with coronary acute syndrome and 551 healthy unrelated controls. A significant difference was observed in the distribution of TGF-β T29C polymorphism between ACS patients and healthy controls (P<10(-3)). According to the co-dominant model, individuals with the TGF-β 29 TT genotype have a 2.5-fold increased risk of developing ACS (P<10(-3)). Multiple logistic analysis showed that the largest risk factor for developing ACS was given by smoking habit, diabetes, hypertension, dyslipidemia, and the TGF-β1 29 TT genotype. The analysis of linkage disequilibrium showed one haplotype (TT) with increased frequency and one haplotype (CC) with decreased frequency in ACS patients when compared to healthy controls. The results suggest that TGF-β1 T29C gene polymorphism could be involved in the risk of developing ACS in Mexican individuals.

TGF-β1 content in atherosclerotic plaques, TGF-β1 serum concentrations and incident coronary events

BACKGROUND

We tested the hypothesis that high TGF-β1 content in atherosclerotic plaques and high TGF-β1 serum levels are associated with lower risk of coronary events in two independent prospective studies.

MATERIALS AND METHODS

In the prospective Athero-Express biobank study, total TGF-β1 plaque levels were measured in 632 atherosclerotic lesions from patients who underwent carotid endarterectomy. In a population-based case-cohort study within the Monitoring of trends and determinants in cardiovascular disease (MONICA)/Cooperative Health Research in the Region of Augsburg (KORA) Augsburg studies, baseline total TGF-β1 serum levels were measured in 333 individuals with and 1728 without incident coronary events.

RESULTS

Patients with TGF-β1 content in their plaques above the study median did not have a lower risk of coronary events than patients with lower TGF-β1 levels [adjusted HR (95% CI) 1·46 (0·83-2·53); P = 0·16; mean follow-up 2·6 ± 0·7 years] in the Athero-Express biobank study. Cox proportional hazard models adjusting for age, sex, body mass index, metabolic factors, lifestyle factors and survey did not reveal a significant association between TGF-β1 serum levels and incident coronary events [HR (95% CI) for increasing TGF-β1 tertiles 1·0, 1·22 (0·88-1·68), 1·13 (0·82-1·57); P = 0·47; mean follow-up: 10·8 ± 4·6 years] in the MONICA/KORA Augsburg studies.

CONCLUSION

Our results indicate that high TGF-β1 content in human atherosclerotic plaques and high serum levels of TGF-β1 are not associated with reduced risk of coronary events.

Association of transforming growth factor-β1 gene polymorphisms with genetic susceptibility to acute myocardial infarction

INTRODUCTION

Transforming growth factor beta 1 (TGF-β1) gene plays an important role in acute myocardial infarction (AMI); however, little is known about the relation of variations within the gene and risk of cardiovascular diseases. In this study, the authors evaluated the influence of TGF-β1 polymorphisms on the onset and progression of AMI in Iranian patients comparing with healthy individuals.

METHODS

Genomic DNA and peripheral blood mononuclear cells of 900 enrolled patients with AMI and 900 control subjects were extracted. The -509 C/T, 868T/C, 913G/C and 11929C/T TGF-β1 polymorphisms were detected. The messenger RNA (mRNA) expression and serum levels of TGF-β1 were analyzed by real-time reverse-transcriptase polymerase chain reaction and ELISA, respectively.

RESULTS

The frequency of "T" allele in -509 C/T, "C" allele in 868T/C, "C" allele in 913G/C and "T" allele in 11929C/T polymorphisms were significantly higher in the patients than control subjects (P < 0.001). There were significant differences in circulating levels of TGF-β1 in the patients than in control subjects (P < 0.001). These concentrations are associated with its gene polymorphism. The mRNA expression levels of TGF-β1 were significantly higher in the patient serums compared with controls (P < 0.001).

CONCLUSIONS

Our results confirmed the association between the TGF-β1 polymorphisms and risk of AMI, which suggest that genetic polymorphisms in TGF-β1 might be helpful for determining susceptibility to AMI in Iranian patients. There are also significant relationship between serum TGF-β1 and occurrence of AMI. In addition, susceptibility to AMI might be related to TGF-β1 gene expression, which affects its serum levels.

TGFβ signaling and cardiovascular diseases

Transforming growth factor β (TGFβ) family members are involved in a wide range of diverse functions and play key roles in embryogenesis, development and tissue homeostasis. Perturbation of TGFβ signaling may lead to vascular and other diseases. In vitro studies have provided evidence that TGFβ family members have a wide range of diverse effects on vascular cells, which are highly dependent on cellular context. Consistent with these observations genetic studies in mice and humans showed that TGFβ family members have ambiguous effects on the function of the cardiovascular system. In this review we discuss the recent advances on TGFβ signaling in (cardio)vascular diseases, and describe the value of TGFβ signaling as both a disease marker and therapeutic target for (cardio)vascular diseases.

Platelet TGF-β1 contributions to plasma TGF-β1, cardiac fibrosis, and systolic dysfunction in a mouse model of pressure overload

Circulating platelets contain high concentrations of TGF-β1 in their α-granules and release it on platelet adhesion/activation. We hypothesized that uncontrolled in vitro release of platelet TGF-β1 may confound measurement of plasma TGF-β1 in mice and that in vivo release and activation may contribute to cardiac pathology in response to constriction of the transverse aorta, which produces both high shear and cardiac pressure overload. Plasma TGF-β1 levels in blood collected from C57Bl/6 mice by the standard retro-bulbar technique were much higher than those obtained when prostaglandin E₁ was added to inhibit release or when blood was collected percutaneously from the left ventricle under ultrasound guidance. Even with optimal blood drawing, plasma TGF-β1 was lower in mice rendered profoundly thrombocytopenic or mice with selectively low levels of platelet TGF-β1 because of megakaryocyte-specific disruption of their TGF-β1 gene (Tgfb1(flox)). Tgfb1(flox) mice were also partially protected from developing cardiac hypertrophy, fibrosis, and systolic dysfunction in response to transverse aortic constriction. These studies demonstrate that plasma TGF-β1 levels can be assessed accurately, but it requires special precautions; that platelet TGF-β1 contributes to plasma levels of TGF-β1; and that platelet TGF-β1 contributes to the pathologic cardiac changes that occur in response to aortic constriction.

Intranasal delivery of E-selectin reduces atherosclerosis in ApoE-/- mice

Mucosal tolerance to E-selectin prevents stroke and protects against ischemic brain damage in experimental models of stroke studying healthy animals or spontaneously hypertensive stroke-prone rats. A reduction in inflammation and neural damage was associated with immunomodulatory or “tolerogenic” responses to E-selectin. The purpose of the current study on ApoE deficient mice is to assess the capacity of this stroke prevention innovation to influence atherosclerosis, a major underlying cause for ischemic strokes; human E-selectin is being translated as a potential clinical prevention strategy for secondary stroke. Female ApoE−/− mice received intranasal delivery of E-selectin prior to (pre-tolerization) or simultaneously with initiation of a high-fat diet. After 7 weeks on the high-fat diet, lipid lesions in the aorta, serum triglycerides, and total cholesterol were assessed as markers of atherosclerosis development. We also assessed E-selectin-specific antibodies and cytokine responses, in addition to inflammatory responses that included macrophage infiltration of the aorta and altered gene expression profiles of aortic mRNA. Intranasal delivery of E-selectin prior to initiation of high-fat chow decreased atherosclerosis, serum total cholesterol, and expression of the leucocyte chemoattractant CCL21 that is typically upregulated in atherosclerotic lesions of ApoE−/− mice. This response was associated with the induction of E-selectin specific cells producing the immunomodulatory cytokine IL-10 and immunosuppressive antibody isotypes. Intranasal administration of E-selectin generates E-selectin specific immune responses that are immunosuppressive in nature and can ameliorate atherosclerosis, a major risk factor for ischemic stroke. These results provide additional preclinical support for the potential of induction of mucosal tolerance to E-selectin to prevent stroke.

Interleukin-17-dependent autoimmunity to collagen type V in atherosclerosis

RATIONALE

Considerable evidence shows atherosclerosis to be a chronic inflammatory disease in which immunity to self-antigens contributes to disease progression. We recently identified the collagen type V [col(V)] α1(V) chain as a key autoantigen driving the Th17-dependent cellular immunity underlying another chronic inflammatory disease, obliterative bronchiolitis. Because specific induction of α1(V) chains has previously been reported in human atheromas, we postulated involvement of col(V) autoimmunity in atherosclerosis.

OBJECTIVE

To determine whether col(V) autoimmunity may be involved in the pathogenesis of atherosclerosis.

METHODS AND RESULTS

Here, we demonstrate Th17-dependent anti-col(V) immunity to be characteristic of atherosclerosis in human coronary artery disease (CAD) patients and in apolipoprotein E-null (ApoE(-/-)) atherosclerotic mice. Responses were α1(V)-specific in CAD with variable Th1 pathway involvement. In early atherosclerosis in ApoE(-/-) mice, anti-col(V) immunity was tempered by an interleukin (IL)-10-dependent mechanism. In support of a causal role for col(V) autoimmunity in the pathogenesis of atherosclerosis, col(V) sensitization of ApoE(-/-) mice on a regular chow diet overcame IL-10-mediated inhibition of col(V) autoimmunity, leading to increased atherosclerotic burden in these mice and local accumulation of IL-17-producing cells, particularly in the col(V)-rich adventitia subjacent to the atheromas.

CONCLUSIONS

These findings establish col(V) as an autoantigen in human CAD and show col(V) autoimmunity to be a consistent feature in atherosclerosis in humans and mice. Furthermore, data are consistent with a causative role for col(V) in the pathogenesis of atherosclerosis.

Changes in transforming growth factor β and its receptors' mRNA expression in monocytes from patients with acute coronary syndromes

INTRODUCTION

Transforming growth factor β (TGF-β) is thought to be a vasoprotective cytokine. Numerous reports confirm its significance in blood and plaques. There is, however, a lack of information on the molecular mechanisms involving TGF-β in circulating inflammatory cells in atherogenesis. sThe aim of the study was to assess gene expression of TGF-β and its receptors in monocytes from patients with acute coronary syndromes (ACS) and the effect of standard treatment on the studied genes.

MATERIAL AND METHODS

The study was carried out in 32 patients with ACS and 15 healthy subjects. Gene expression of TGF-β and receptors TGF-βRI and TGF-βRII was evaluated on day 1 and 5 in the study group and once in controls. The number of mRNA copies isolated from monocytes was assessed by QRT-PCR.

RESULTS

Monocytes of ACS patients showed slightly elevated transcriptional activity of TGF-β1 and its receptors RI and RII genes (0.29 ±0.043 vs. 0.08 ±0.020, p = 0.05; 0.071 ±0.022 vs. 0.036 ±0.023, p < 0.05; 0.134 ±0.020 vs. 0.048 ±0.016, p < 0.05, respectively). After 5-day standard treatment modest reduction of TGF-βRI expression was observed. The studied genes' expression was unrelated to ejection fraction, myocardial necrosis markers, GRACE score, time from the onset of pain to percutaneous coronary intervention and angiographic findings. Among risk factors family history of CAD was associated with increased TGF-βRI expression. Moreover, the presence of 4 or more classic risk factors correlated with higher TGF-βRI expression.

CONCLUSIONS

Monocytes of ACS patients demonstrate overexpression of TGF-β1 and its receptors' genes. Five-day standard treatment downregulated the TGF-βRI gene but did not affect TGF-β1 and TGF-βRII.

Genetic determinants of osteoporosis: common bases to cardiovascular diseases?

Osteoporosis is the most common and serious age-related skeletal disorder, characterized by a low bone mass and bone microarchitectural deterioration, with a consequent increase in bone fragility and susceptibility to spontaneous fractures, and it represents a major worldwide health care problem with important implications for health care costs, morbidity and mortality. Today is well accepted that osteoporosis is a multifactorial disorder caused by the interaction between environment and genes that singularly exert modest effects on bone mass and other aspects of bone strength and fracture risk. The individuation of genetic factors responsible for osteoporosis predisposition and development is fundamental for the disease prevention and for the setting of novel therapies, before fracture occurrence. In the last decades the interest of the Scientific Community has been concentrated in the understanding the genetic bases of this disease but with controversial and/or inconclusive results. This review tries to summarize data on the most representative osteoporosis candidate genes. Moreover, since recently osteoporosis and cardiovascular diseases have shown to share common physiopathological mechanisms, this review also provides information on the current understanding of osteoporosis and cardiovascular diseases common genetic bases.

Stem cells, microenvironment mechanics, and growth factor activation

Physicochemical features of a cell's microenvironment can exert important effects on cell behavior and include the effects of matrix elasticity on cell differentiation processes, but molecular mechanisms are largely mysterious. Here we highlight recent reports of a mechanical dependence to growth factor activation, with a particular focus on release of TGFbeta (Transforming Growth Factor beta) from its large latent complex via forced unfolding. We discuss these processes and pathways in the contexts of matrix adhesion and fluid shearing as they might relate to stem cell differentiation and other mechanisms in development, disease, and repair.

The Role of Interleukin-6 and Transforming Growth Factor-β1 in Predicting Restenosis within Stented Infarct-Related Artery

Despite high efficacy of percutaneous coronary intervention (PCI), in-stent restenosis proves to be a significant problem of therapy. Restenosis concerns around 30% of patients. Studies have suggested that restenosis is initiated by cells which participate in intense inflammatory reaction caused by stent implantation. Atherosclerotic plaque rupture during stent implantation and PCI-associated injury of the vessel wall lead to hemorrhage and release of various cytokines. They are probably responsible for quick recurrence of vascular lumen stenosis (restenosis). Interleukin-6 (IL-6) is known as a main pro-inflammatory cytokine, whereas Transformig Growth Factor-β1 (TGF-β1) has anti-inflammatory properties. The study population comprised 36 patients with myocardial infarction treated with PCI with stent implantation. They underwent control coronary angiography after 12 months. At this time plasma concentration of IL-6 and TGF-β was measured in peripheral blood. Serum IL-6 concentration in the analyzed population correlates with lumen loss (p<0.01) and the severity of stenosis (p<0.001). No such correlation was found between serum TGF-β1 concentration and lumen loss (p=NS) or the severity of stenosis (p=NS). The IL-6 plasma concentration may be a marker of in-stent restenosis in patients after PTCA, while the concentration of TGF-β1 is not associated with the occurrence of restenosis at one year of follow-up.

Inflammatory cytokine gene variants in coronary artery disease patients in Greece

OBJECTIVE

Abundant evidence supports the central role of inflammatory cytokines in immune responses mediating the pathogenesis of atherosclerosis, coronary artery disease, and its complications, such as myocardial infarction and unstable angina.

METHODS

We investigated the association of genetic polymorphisms of the inflammatory cytokines, IL-10, TGF-beta1, IFN-gamma, IL-6, and TNF-alpha with the clinical presentation of coronary artery disease in 26 patients with stable angina, 45 patients with unstable angina and 58 patients who had experienced nonfatal myocardial infarction. Genotyping was performed by the sequence-specific primer polymerase chain reaction method.

RESULTS

A significant difference in the frequencies of -174G/C IL-6 alleles was observed, with the low in-vitro producing -174*C allele predominating in patients with myocardial infarction, compared with stable angina and unstable angina patients, after the analysis of genotypes (P=0.024 and 0.022, respectively), phenotypes [P=0.0099, odds ratio (OR)=0.271, 95% confidence interval (CI)=0.1012-0.7292; P=0.03, OR=0.40, respectively] and haplotypes (P=0.007, OR=3.028, 95% CI=1.347-6.806; P=0.0096, OR=2.368, 95% CI=1.262-4.444; respectively). In addition, a predominance of the -1082ACC/ATA IL-10 genotype in the myocardial infarction group compared with the unstable angina group and the -874 A/A IFN-gamma genotype in the stable angina group compared with the unstable angina and the myocardial infarction group, was found. No significant differences in the distribution of genotypes, phenotypes and haplotypes in the three study groups, for the TNF-alpha-308 A/G and TGF-beta1-codon 25 G/C, codon 10 T/C polymorphisms were detected.

CONCLUSION

Our data provide evidence that the IL-6-174G/C polymorphism may be involved in the pathogenesis of coronary artery disease, contributing to genetic susceptibility for myocardial infarction.

Exogenous transforming growth factor beta1 replacement and fertility in male Tgfb1 null mutant mice

Analysis of Tgfb1 null mutant mice has demonstrated that the cytokine transforming growth factor β1 (TGFB1) has essential non-redundant roles in fertility. The present study attempted to alleviate the infertility phenotype of Tgfb1 null mutant male mice by administration of exogenous TGFB1, either orally by colostrum feeding or subcutaneously by delivery of recombinant human latent TGFB1 (rhLTGFB1) via osmotic mini-pumps. Bovine colostrum and fresh unpasteurised bovine milk were found to be rich sources of TGFB1 and TGFB2; however, feeding Tgfb1 null mutant mice colostrum for 2 days failed to raise serum levels of TGFB1. Administration of rhLTGFB1 (~150 μg in total) over 14 days to Tgfb1 null mutant mice resulted in detectable TGFB1 in serum; however, mean levels remained 10-fold less than in Tgfb1 heterozygous mice. After 7 days and 14 days of rhLTGFB1 administration, serum testosterone, spontaneous non-contact erections and mating behaviour were assessed. Despite the increased serum TGFB1, administration of rhLTGFB1 to Tgfb1 null mutant mice failed to improve these fertility parameters. It is concluded that sustained restoration of circulating latent TGFB1 to levels approaching the normal physiological range does not rescue the infertility phenotype caused by TGFB1 deficiency. Reproductive function in male Tgfb1 null mutant mice may not respond to systemic TGFB1 supplementation due to a requirement for local sources of TGFB1 at the site of action in the reproductive tract, or perturbed development during the neonatal period or puberty such that adult reproductive function is permanently impaired.

Hypercholesterolemia leads to elevated TGF-beta1 activity and T helper 3-dependent autoimmune responses in atherosclerotic mice

OBJECTIVE

The pathogenesis of atherosclerosis involves inflammation and immune reactions. Low-density lipoproteins accumulate and are oxidized (oxLDL) in the arterial intima during hypercholesterolemia, leading to activation of endothelial cells, macrophages and T cells. We have previously found that severe hypercholesterolemia can induce a switch of autoimmune responses from T helper (Th)1 to Th2 effector type in atherosclerotic apoE knockout (E0) mice. The present study was performed to investigate whether Th3 immune effector responses and their inducing cytokine, transforming growth factor-beta (TGF-beta) are affected by hypercholesterolemia.

METHODS AND RESULTS

In E0 mice fed with high cholesterol diet and in C57BL/6J mice treated with poloxamer P-407, an agent that elevates plasma cholesterol and triglycerides, severe hypercholesterolemia led to elevated circulating TGF-beta1 levels, increased TGF-beta1(+)CD4(+) Th3 cells in lesions and spleen, and increased Th3 dependent IgG2b antibodies to oxLDL. A positive correlation was observed between plasma TGF-beta1 and cholesterol levels and between plasma TGF-beta1 and IgG2b anti-oxLDL.

CONCLUSIONS

Such elevation of TGF-beta may increase the stability of plaques by inhibiting T cell responses and macrophage activation and by stimulating collagen synthesis. This new finding could be important in the regulation of immune activity, inflammation and fibrosis in the atherosclerotic plaque.

Platelets, but not erythrocytes, significantly affect cytokine release and scaffold contraction in a provisional scaffold model

Platelets and erythrocytes are major components of wound provisional scaffolding. In this study, we hypothesized that the concentration of platelets and erythrocytes would significantly affect fibroblast-mediated contraction of three-dimensional scaffolds or the release of cytokines from the scaffold. To test this hypothesis, human anterior cruciate ligament fibroblasts were cultured in one of four scaffolds: a collagen matrix, a collagen-fibrin matrix containing the same concentration of platelets as whole blood, a collagen-fibrin matrix containing a high platelet concentration, and a collagen-fibrin matrix containing a high platelet concentration and red blood cells. Cytokine release from the four groups of gels and gel contraction were measured over a 10-day period. The results of these assays supported greater cytokine release, fibroblast proliferation, and gel contraction in scaffolds with higher platelet concentration. In contrast, the addition of erythrocytes did not significantly stimulate or suppress scaffold contraction or growth factor release from the provisional scaffolds. We concluded that while platelet concentration can significantly impact cytokine release and scaffold retraction in a provisional scaffold, the inclusion of erythrocytes does not have a significant effect on these same behaviors. Therefore, while platelets may be an important regulator of repair processes after injury, it is less likely that erythrocytes have a similar function.

In vitro and in vivo evidence for shear-induced activation of latent transforming growth factor-beta1

Transforming growth factor-beta1 (TGF-beta1) has potent physiologic and pathologic effects on a variety of cell types at subnanomolar concentrations. Platelets contain 40 times as much TGF-beta1 as other cells and secrete it as an inactive (latent) form in complex with latency-associated peptide (LAP), which is disulfide bonded via Cys33 to latent TGF-beta binding protein 1 (LTBP-1). Little is known about how latent TGF-beta1 becomes activated in vivo. Here we show that TGF-beta1 released from platelets or fibroblasts undergoes dramatic activation when subjected to stirring or shear forces, providing a potential mechanism for physiologic control. Thiol-disulfide exchange appears to contribute to the process based on the effects of thiol-reactive reagents and differences in thiol labeling of TGF-beta1 before and after stirring or shear. Activation required the presence of LTBP, as TGF-beta1 contained in complex with only LAP could not be activated by stirring when studied as either a recombinant purified protein complex or in the platelet releasates or sera of mice engineered to contain an LAP C33S mutation. Release and activation of latent TGF-beta1 in vivo was demonstrated in a mouse model 5 minutes after thrombus formation. These data potentially provide a novel mechanism for in vivo activation of TGF-beta1.

Activation of platelet-rich plasma using soluble type I collagen

PURPOSE

Platelet-rich plasma (PRP) has recently been found to be a useful delivery system for growth factors important to oral tissue healing. But application of PRP in a liquid form to a wound site within the oral cavity can be complicated by significant loss of the PRP into the surrounding oral space unless gelation through the clotting mechanism is accomplished. Gelation is currently accomplished using bovine thrombin; however, rare but serious complications of this method have led to the search for alternative clotting mechanisms, including the use of soluble collagen as a clotting activator. In this work, our hypothesis was that soluble type I collagen would be as effective as bovine thrombin in causing clotting of the PRP and stimulating growth factor release from the platelets and granulocytes.

MATERIALS AND METHODS

PRP from human donors was clotted using type I collagen or bovine thrombin. Clot retraction was determined by measuring clot diameters over time. The release of platelet-derived growth factor (PDGF)-AB, transforming growth factor (TGF)-beta1, and vascular endothelial growth factor (VEGF) from both types of clots was measured over 10 days using enzyme-linked immunosorbent assasy.

RESULTS

Clots formed using type I collagen exhibited far less retraction than those formed with bovine thrombin. Bovine thrombin and type I collagen stimulated similar release of PDGF-AB and VEGF between 1 and 10 days; however, thrombin activation resulted in a greater release of TGF-beta1 during the first 5 days after activation.

CONCLUSIONS

The use of type I collagen to activate clotting of PRP may be a safe and effective alternative to bovine thrombin. The use of collagen results in less clot retraction and equal release of PDGF-AB and VEGF compared with currently available methods of clot activation.

'Correction:' Serum transforming growth factor beta-1 (TGF-beta-1) levels in diabetic patients are not associated with pre-existent coronary artery disease

Background

The association between TGF-β1 levels and long-term major adverse cardiovascular events (MACE) in patients with coronary artery disease (CAD) is controversial. No study specifically addressed patients with CAD and diabetes mellitus (DM). The association between TGF-β1 levels and long-term major adverse cardiovascular events (MACE) in patients with coronary artery disease (CAD) is controversial. No study specifically addressed patients with CAD and diabetes mellitus (DM).

Methods

Patients (n = 135, 30–80 years) referred for coronary angiography were submitted to clinical and laboratory evaluation, and the coronary angiograms were evaluated by two operators blinded to clinical characteristics. CAD was defined as the presence of a 70% stenosis in one major coronary artery, and DM was characterized as a fasting glycemia > 126 mg/dl or known diabetics (personal history of diabetes or previous use of anti-hyperglycemic drugs or insulin). Based on these criteria, study patients were classified into four groups: no DM and no CAD (controls, C n = 61), DM without CAD (D n = 23), CAD without DM (C-CAD n = 28), and CAD with DM (D-CAD n = 23). Baseline differences between the 4 groups were evaluated by the χ² test for trend (categorical variables) and by ANOVA (continuous variables, post-hoc Tukey). Patients were then followed-up during two years for the occurrence of MACE (cardiac death, stroke, myocardial infarction or myocardial revascularization). The association of candidate variables with the occurrence of 2-year MACE was assessed by univariate analysis.

Results

The mean age was 58.2 ± 0.9 years, and 51% were men. Patients with CAD had a higher mean age (p = 0.011) and a higher percentage were male (p = 0.040). There were no significant baseline differences between the 4 groups regarding hypertension, smoking status, blood pressure levels, lipid levels or inflammatory markers. TGF-β1 was similar between patients with or without CAD or DM (35.1 ×/÷ 1.3, 33.6 ×/÷ 1.6, 33.9 ×/÷ 1.4 and 31.8 ×/÷ 1.4 ng/ml in C, D, C-CAD and D-CAD, respectively, p = 0.547). In the 2-year follow-ip, independent predictors of 2-year MACE were age (p = 0.007), C-reactive protein (p = 0.048) and systolic blood pressure (p = 0.008), but not TGF-β1.

Conclusion

Serum TGF-β1 was not associated with CAD or MACE occurrence in patients with or without DM.

TGF-β1: a novel target for cardiovascular pharmacology

Transforming growth factor beta-1 (TGF-beta1) plays a key role in cardiovascular disease by a process which allows the loss of its protective properties. The first therapeutic attempt to restore its function by selectively designed novel drugs are being made. In addition, it has been recognized that the TGF-beta1 pathway is involved in the vascular mechanism of action of some current clinical drugs, such as acetylsalicylic acid, thiazolidinediones and statins. The aim of this paper is to review the possible value of TGF-beta1 as both a disease marker and a therapeutical target for cardiovascular disease.

Cyclooxygenase-2 inhibitor ameliorates ureteric damage in rats with obstructed uropathy

To investigate the effect of cyclooxygenase-2 (COX-2) inhibitor on the tissue damage and fibrosis in obstructed ureters, 80 rats were studied. Celecoxib, a COX-2 inhibitor, was administered to 40 rats at the dose of 10 mg/kg per day 1 day before unilateral ligation of ureters and every day thereafter. The others, receiving unilateral ligation of ureters only, served as controls. Eight rats from each group were sacrificed for examination on days 7, 14, 21, 28 and 42 after ligation, respectively. The expressions of COX-2, prostaglandin E(2) (PGE(2)), transforming growth factor-beta(1) (TGFbeta(1)), alpha-smooth muscle actin (alpha-SMA), proliferation cell nuclear antigen (PCNA) and the apoptotic cells in the ureteric smooth muscle were examined. Hydroureter and fibrosis of the muscle layer became progressively aggravated during the period of obstruction in the ligated ureters of both groups. The severity of the hydroureter and fibrosis of muscle layer in the ligated ureters of the treated group was significantly milder than those of the control group. Expressions of COX-2 and PGE(2) were found in the smooth muscle layer of ligated ureters in the control group from day 14 after ureteric ligation, reached a peak on day 21, and then declined. Treatment with Celecoxib completely abolished the expression of COX-2 and PGE(2). The Celecoxib administration also decreased the expression of TGFbeta(1), alpha-SMA and the labeling index of apoptotic cells in the smooth muscle layer of ligated ureters in the treated group. In the contrast, treatment with Celecoxib significantly increased the expression of PCNA in the smooth muscle layer of ligated ureters in the treated group. We concluded that COX-2 inhibitor might ameliorate the damage of obstructed ureters, at least partly, via the inhibition of COX-2 and TGFbeta(1) expression.

The anti-inflammatory properties of cocoa flavanols

Signs of chronic or acute inflammation have been demonstrated in most cardiovascular diseases of multifactorial pathogenesis, including atherosclerosis and chronic heart failure. The triggers and mechanisms leading to inflammation may vary between clinical conditions but they share many common mediators, including specific patterns of eicosanoid and cytokine production. Certain cocoa-based products can be rich in a subclass of flavonoids known as flavanols, some of which have been found in model systems to possess potential anti-inflammatory activity relevant to cardiovascular health. Indeed, experimental evidence demonstrates that some cocoa-derived flavanols can reduce the production and effect of pro-inflammatory mediators either directly or by acting on signaling pathways. However, it should be noted that the evidence for any beneficial effects of cocoa flavanols in providing a meaningful anti-inflammatory action has been gathered predominantly from in vitro experiments. Therefore, additional research in well-designed human clinical experiments, using cocoa properly characterized in terms of flavanol content, would be a welcome addition to the evidence base to determine unambiguously if this benefit does indeed exist. If so, then flavanol-rich cocoa could be a potential candidate for the treatment, or possibly prevention, of the broad array of chronic diseases that are linked to dysfunctional inflammatory responses.

TGF-beta 1 polymorphisms and risk of myocardial infarction and stroke: the Rotterdam Study

BACKGROUND AND PURPOSE

Inflammation plays a pivotal role in the pathogenesis of atherosclerosis and of cardiovascular and cerebrovascular complications. Transforming growth factor-beta1 (TGF-beta1) is a pleiotropic cytokine with a central role in inflammation. Little is known of the relation of variations within the gene and risk of cardiovascular and cerebrovascular disease. We therefore investigated 5 polymorphisms in the TGF-beta1 gene (-800 G/A, -509 C/T, codon 10 Leu/Pro, codon 25 Arg/Pro, and codon 263 Thr/Ile) in relation to the risk of myocardial infarction and stroke in a population-based study.

METHODS

Participants (N=6456) of the Rotterdam Study were included in the current study. Analyses of the relations of genotypes with the risk of myocardial infarction and stroke were performed according to Cox proportional-hazards methods. All analyses were adjusted for age, sex, conventional cardiovascular risk factors, and medical history.

RESULTS

We found no association with the risk of myocardial infarction. A significantly increased risk of stroke was found, associated with the T allele of the -509 C/T polymorphism (relative risk, 1.26; (95% CI, 1.06 to 1.49) and the Pro variant of the codon 10 polymorphism (relative risk, 1.24; 95% CI, 1.04 to 1.48).

CONCLUSIONS

No association between the TGF-beta1 polymorphisms and myocardial infarction was observed; however, the -509 C/T and codon 10 Leu/Pro polymorphisms were associated with the risk of stroke.

A pattern of anti-carbohydrate antibody responses present in patients with advanced atherosclerosis

We have previously shown that an antibody pool present in normal human serum binds cytokine receptors in vitro and may therefore interfere with assays that capture cytokines using their receptors. Here we show that this antibody pool is the same as the natural antibody termed anti-gal, that binds to the alpha-galactosyl carbohydrate epitope (alpha-gal) and which is the predominant obstacle to xenotransplantation. We report that there are high levels of IgD anti alpha-gal in most volunteers, in addition to the IgG2, IgA and IgM immunoglobulin isotypes against alpha-gal previously described. To determine if anti-gal may interfere with assays that depend on capture of cytokine with its receptor, we measured levels of several anti-carbohydrate antibodies in a cohort of patients with advanced atherosclerosis that had previously been used to measure levels of active TGF-beta using such an assay. For many isotype / carbohydrate combinations, there is a large and significant difference between the levels of anti-carbohydrate antibodies in patients with atherosclerosis and controls, after adjustment for age, sex and blood group. These results are similar to the previous data obtained for active TGF-beta, and therefore we cannot discount the possibility that anti-gal contributed to the previous data. Following further adjustment for several risk factors associated with cardiovascular disease, several anti-carbohydrate antibodies were still significantly different between patients and controls. Therefore, anti-carbohydrate antibodies may represent a new class of risk factors that may be associated with presence of advanced atherosclerosis, although larger studies will be required to confirm this hypothesis.