Prognostic significance of plasma concentrations of transforming growth factor-beta in patients with coronary artery disease

Exogenous Transforming Growth Factor-β1 and Its Helminth-Derived Mimic Attenuate the Heart's Inflammatory Response to Ischemic Injury and Reduce Mature Scar Size

Coronary reperfusion after acute ST-elevation myocardial infarction (STEMI) is standard therapy to salvage ischemic heart muscle. However, subsequent inflammatory responses within the infarct lead to further loss of viable myocardium. Transforming growth factor (TGF)-β1 is a potent anti-inflammatory cytokine released in response to tissue injury. The aim of this study was to investigate the protective effects of TGF-β1 after MI. In patients with STEMI, there was a significant correlation (P = 0.003) between higher circulating TGF-β1 levels at 24 hours after MI and a reduction in infarct size after 3 months, suggesting a protective role of early increase in circulating TGF-β1. A mouse model of cardiac ischemia reperfusion was used to demonstrate multiple benefits of exogenous TGF-β1 delivered in the acute phase. It led to a significantly smaller infarct size (30% reduction, P = 0.025), reduced inflammatory infiltrate (28% reduction, P = 0.015), lower intracardiac expression of inflammatory cytokines IL-1β and chemokine (C-C motif) ligand 2 (>50% reduction, P = 0.038 and 0.0004, respectively) at 24 hours, and reduced scar size at 4 weeks (21% reduction, P = 0.015) after reperfusion. Furthermore, a low-fibrogenic mimic of TGF-β1, secreted by the helminth parasite Heligmosomoides polygyrus, had an almost identical protective effect on injured mouse hearts. Finally, genetic studies indicated that this benefit was mediated by TGF-β signaling in the vascular endothelium.

Decreased circulating transforming growth factor-beta (TGF-β) and kidney TGF-β immunoreactivity predict renal disease in cats with naturally occurring chronic kidney disease

OBJECTIVES

The aim of the present study was to compare the circulating transforming growth factor-beta (TGF-β) of clinically normal age-matched and naturally occurring chronic kidney disease (CKD) cats and to determine the correlation between the TGF-β expression and histopathological changes in cats with CKD.

METHODS

A total of 11 clinically normal age-matched and 27 cats with naturally occurring CKD were included in this study. Circulating TGF-β was quantified by immunoassays. Kaplan-Meier analysis was used to calculate the association between survival time and the concentration of circulating TGF-β. A general linear model was used to compare the circulating TGF-β between groups. Immunohistochemical analyses revealed TGF-β expression in renal tissues from cats with CKD that died during the study (n = 7) and in available archived renal tissue specimens taken at necropsy from cats that had previous CKD with renal lesions (n = 10). Correlations of the TGF-β expression and clinical parameters (n = 7) and histopathological changes (n = 17) were analysed using Spearman's rank correlation.

RESULTS

The median survival time of cats with a lower concentration of circulating TGF-β was shorter than that of cats with a higher concentration. The area under the curve of circulating TGF-β for predicting CKD was 0.781, indicating good differentiation. The study indicated a significant difference in circulating TGF-β concentrations between clinically normal cats and those with CKD and demonstrated that TGF-β expression is correlated with tubular atrophy.

CONCLUSIONS AND RELEVANCE

The study findings suggest that decreased serum TGF-β and tubular atrophy with TGF-β immunoreactivity may be significant in cats with CKD.

The comparison of serum TGF-beta levels and associated polymorphisms in patients with coronary artery ectasia and normal coronary artery

Background

Coronary artery ectasia (CAE) is described as the enlargement of a coronary artery segment by 1.5 times or more, which is generally associated with the atherosclerotic process. Atherosclerotic changes lead to arterial remodeling result in CAE. In our study, we measured serum transforming growth factor (TGF)-β1 levels, which have a protective role against atherosclerosis. Further, we aimed to assess the TGF-β1 gene variants rs1800469 (–509C>T, c.−1347C>T) and rs1800470 (c.+29T>C, p.Pro10Leu, rs1982073), which might have an effect on TGF production. Overall, 2877 patients were screened including 56 patients with CAE and 44 patients with normal coronary arteries who were included in the study. Serum TGF-β1 levels were measured using ELISA and compared between two groups. Additionally, TGF-β1 rs1800469 and rs1800470 gene variations were determined using TaqMan® SNP Genotyping Assays.

Results

Serum TGF-β1 levels were significantly lower in patients with CAE than in controls (p=0.012). However, there was no difference in terms of the genotype and allele distributions of TGF-β1 rs1800469 and rs1800470 polymorphisms. Serum TGF-β1 levels were higher in individuals carrying the TGF-β1 rs1800470 G allele (GG+AG) than in individuals with normal homozygous AA genotype in the CAE group (p=0.012).

Conclusion

Our findings suggest that lower serum TGF-β1 levels are associated with an increased risk for CAE development and that TGF-β1 polymorphisms exert a protective effect. Furthermore, TGF-β1 rs1800470 G allele carriers were shown to have higher TGF-β1 levels in the CAE group. This suggests that having the G allele in the TGF-β1 rs1800470 polymorphism could prevent CAE development.

Transforming Growth Factor Beta (TFG-β) Concentration Isoforms are Diminished in Acute Coronary Syndrome

Acute coronary syndrome (ACS) is the leading cause of death in elderly patients worldwide. Due its participation in apoptosis, fibrosis, and angiogenesis, transforming growth factor-β (TGF-β) isoforms had been categorized as risk factors for cardiovascular diseases. However, due their contradictory activities, a cardioprotective role has been suggested. The aim was to measure the plasma levels of TGF-β1, 2, and 3 proteins in patients with ACS. This was a case-control study including 225 subjects. The three activated isoforms were measured in serum using the Bio-Plex Pro TGF-β assay by means of magnetic beads; the fluorescence intensity of reporter signal was read in a Bio-Plex Magpix instrument. We observed a significant reduction of the three activated isoforms of TGF-β in patients with ACS. The three TGF-β isoforms were positively correlated with each other in moderate-to-strong manner. TGFβ-2 was inversely correlated with glucose and low-density lipoprotein (LDL)-cholesterol, whereas TGF-β3 was inversely correlated with the serum cholesterol concentration. The production of TGF-β1, TGF-β2, and TGF-β3 are decreased in the serum of patients with ACS. Further follow-up controlled studies with a larger sample size are needed, in order to test whether TGF-β isoforms could be useful as biomarkers that complement the diagnosis of ACS.

7-Dehydrocholesterol (7-DHC), But Not Cholesterol, Causes Suppression of Canonical TGF-β Signaling and Is Likely Involved in the Development of Atherosclerotic Cardiovascular Disease (ASCVD)

For several decades, cholesterol has been thought to cause ASCVD. Limiting dietary cholesterol intake has been recommended to reduce the risk of the disease. However, several recent epidemiological studies do not support a relationship between dietary cholesterol and/or blood cholesterol and ASCVD. Consequently, the role of cholesterol in atherogenesis is now uncertain. Much evidence indicates that TGF-β, an anti-inflammatory cytokine, protects against ASCVD and that suppression of canonical TGF-β signaling (Smad2-dependent) is involved in atherogenesis. We had hypothesized that cholesterol causes ASCVD by suppressing canonical TGF-β signaling in vascular endothelium. To test this hypothesis, we determine the effects of cholesterol, 7-dehydrocholesterol (7-DHC; the biosynthetic precursor of cholesterol), and other sterols on canonical TGF-β signaling. We use Mv1Lu cells (a model cell system for studying TGF-β activity) stably expressing the Smad2-dependent luciferase reporter gene. We demonstrate that 7-DHC (but not cholesterol or other sterols) effectively suppresses the TGF-β-stimulated luciferase activity. We also demonstrate that 7-DHC suppresses TGF-β-stimulated luciferase activity by promoting lipid raft/caveolae formation and subsequently recruiting cell-surface TGF-β receptors from non-lipid raft microdomains to lipid rafts/caveolae where TGF-β receptors become inactive in transducing canonical signaling and undergo rapid degradation upon TGF-β binding. We determine this by cell-surface 125 I-TGF-β-cross-linking and sucrose density gradient ultracentrifugation. We further demonstrate that methyl-β-cyclodextrin (MβCD), a sterol-chelating agent, reverses 7-DHC-induced suppression of TGF-β-stimulated luciferase activity by extrusion of 7-DHC from resident lipid rafts/caveolae. These results suggest that 7-DHC, but not cholesterol, promotes lipid raft/caveolae formation, leading to suppression of canonical TGF-β signaling and atherogenesis. J. Cell. Biochem. 118: 1387-1400, 2017. © 2016 Wiley Periodicals, Inc.

The 9p21.3 risk locus for coronary artery disease: A 10-year search for its mechanism

The 9p21.3 risk locus is the first locus to be associated with an increased risk of coronary artery disease (CAD)-related events and many other phenotypes. This locus contains 59 single nucleotide polymorphisms (SNPs) in a region with multiple long range enhancers and long non-coding RNAs (lncRNAs) that affect the expression of neighbouring genes, cyclin-dependent kinase 2A and 2B (CDKN2A and CDKN2B), which are required for controlling vascular smooth muscle cell proliferation and ageing. Several studies have attempted to identify the precise mechanism by which this locus exerts its pathogenic effect to increase the risk of CAD-related events. In this review, we will highlight the major advances in our understanding of the genotype–phenotype correlation at the mechanistic and phenotypic levels. The high population attributable risk of the 9p21.3 risk locus, mechanistic knowledge acquired thus far, and ongoing research efforts could facilitate the design of novel therapeutic molecules to reduce the risk of CAD and its related events.

Association of transforming growth factor-β1 gene C509T, G800A and T869C polymorphisms with intracerebral hemorrhage in North Indian Population: a case-control study

Transforming growth factor-β1 (TGF-β1) is a multifunctional pro-inflammatory cytokine involved in inflammation and pathogenesis of cerebrovascular disease. As per our knowledge, there is no published study investigating the association between variations within the TGF-β1 gene polymorphisms and risk of intracerebral hemorrhage (ICH). The aim of this study was to investigate the association of the TGF-β1 gene (C509T, G800A and T869C) polymorphisms, and their haplotypes with the risk of ICH in North Indian population. 100 ICH patients and 100 age- and sex-matched controls were studied. Genotyping was performed using SNaPshot method. Conditional logistic regression analysis was used to calculate the strength of association between TGF-β1 gene polymorphisms and risk of ICH. Hypertension, diabetes, dyslipidemia, low socioeconomic status, smoking, physical activity were found to be associated with the risk of ICH. The distribution of C509T, G800A and T869C genotypes was consistent with Hardy-Weinberg Equilibrium (HWE) in the ICH and control group. Adjusted conditional logistic regression analysis showed an independent association of TGF-β1 G800A (OR 9.07; 95% CI 2.3-35.6; P = 0.002) and T869C (OR 5.1; 95 % CI 1.9-13.2; P = 0.001) with the risk of ICH under dominant model. Haplotype analysis showed that C509-G800-C869 and C509-A800-C869 haplotypes were significantly associated with the increased risk of ICH. C509T and T869C were in strong linkage disequilibrium (D' = 0.53, r(2) = 0.23). Our results suggest that TGF-β1 (G800A, T869C) gene polymorphisms and their haplotypes are significantly associated with the risk of ICH in North Indian population. Further prospective studies with large sample size are required for independent validation. Our findings could be helpful in identifying individuals at increased risk for developing ICH.

Transforming growth factor (TGF)-β levels and unprovoked recurrent venous thromboembolism

Prediction of recurrence in patients with unprovoked venous thromboembolism (VTE) remains a challenge. Studies of atherosclerosis suggest a protective role of transforming growth factor (TGF)-β. However, the role of TGF-β has not been studied in VTE. The aim of this study was to investigate TGF-β as a predictive marker of recurrent VTE in patients with a first episode of unprovoked VTE. Patients in the Malmö Thrombophilia Study (MATS) were followed after the discontinuation of anticoagulant treatment until the diagnosis of recurrent VTE or the end of the study in December 2008 (mean ± SD 38.5 months ± 27). Among patients with a first episode of unprovoked VTE, we identified 42 patients with recurrent VTE during the follow-up period. Two age- and sex-matched control subjects without recurrent VTE were selected for each patient (n = 84). Plasma levels of the three isoforms of TGF-β (TGF-β1, TGF-β2 and TGF-β3) were quantified simultaneously by TGF-β 3-plex immunoassay. Compared to controls, plasma levels of TGF-β1 and TGF-β2 were significantly lower in patients with recurrent VTE (p < 0.05), whereas no difference was found for TGF-β3. In a multivariate Cox regression analyses, adjusted for inherited thrombophilia, age, sex and BMI, low levels of TGF-β1 [hazard ratio (HR) = 2.2, 95% confidence interval (CI) 1.1-4.3; p = 0.02] and TGF-β2 (HR = 2.4, 95% CI 1.2-4.7; p = 0.01) were independently associated with a higher risk of recurrent VTE. We propose TGF-β1 and TGF-β2 as potential predictive markers for recurrence in patients with unprovoked VTE.

Functional genomics of the 9p21.3 locus for atherosclerosis: clarity or confusion?

The 9p21.3 locus was the first to yield to genome-wide association studies (GWAS) seeking common genetic variants predisposing to increased risk of coronary artery atherosclerotic disease (CAD). The 59 single nucleotide polymorphisms that show highest association with CAD are clustered in a region 100,000 to 150,000 base pairs 5' to the cyclin-dependent kinase inhibitors CDKN2B (coding for p15(ink4b)) and CDKN2A (coding for p16(ink4a) and p14(ARF)). This region also covers the 3' end of a long noncoding RNA transcribed antisense to CDKN2B (CDKN2BAS, aka ANRIL for antisense noncoding RNA at the ink4 locus) whose expression has been linked to chromatin remodeling at the locus. Despite intensive investigation over the past 7 years, the functional significance of the 9p21.3 locus remains elusive. Other variants at this locus have been associated with glaucoma, glioma, and type 2 diabetes mellitus, diseases that implicate tissue-resident macrophages. Here, we review the evidence that genetic variants at 9p21.3 disrupt tissue-specific enhancers and propose new insights to guide future studies.

Fibrosis-related biomarkers and incident cardiovascular disease in older adults: the cardiovascular health study

BACKGROUND

Fibrotic changes in the heart and arteries have been implicated in a diverse range of cardiovascular diseases (CVD), but whether circulating biomarkers that reflect fibrosis are associated with CVD is unknown.

METHODS AND RESULTS

We determined the associations of 2 biomarkers of fibrosis, transforming growth factor- β (TGF-β), and procollagen type III N-terminal propeptide (PIIINP), with incident heart failure, myocardial infarction, and stroke among community-living older adults in the Cardiovascular Health Study. We measured circulating TGF-β (n=1371) and PIIINP (n=2568) from plasma samples collected in 1996 and ascertained events through 2010. Given TGF-β's pleiotropic effects on inflammation and fibrogenesis, we investigated potential effect modification by C-reactive protein in secondary analyses. After adjustment for sociodemographic, clinical, and biochemical risk factors, PIIINP was associated with total CVD (hazard ratio [HR] per SD=1.07; 95% confidence interval [CI], 1.01-1.14) and heart failure (HR per SD=1.08; CI, 1.01-1.16) but not myocardial infarction or stroke. TGF-β was not associated with any CVD outcomes in the full cohort but was associated with total CVD (HR per SD=1.16; CI, 1.02-1.31), heart failure (HR per SD=1.16; CI, 1.01-1.34), and stroke (HR per SD=1.20; CI, 1.01-1.42) among individuals with C-reactive protein above the median, 2.3 mg/L (P interaction <0.05).

CONCLUSIONS

Our findings provide large-scale, prospective evidence that circulating biomarkers of fibrosis, measured in community-living individuals late in life, are associated with CVD. Further research on whether TGF-β has a stronger fibrogenic effect in the setting of inflammation is warranted.

Serum TGF-β1 and SMAD3 levels are closely associated with coronary artery disease

Background

Coronary artery disease (CAD) is one of the most common diseases leading to mortality and morbidity worldwide. There is considerable debate on whether serum transforming growth factor β1 (TGF-β1) levels are associated with long-term major adverse cardiovascular events in patients with CAD, and to date, no study has specifically addressed levels in patients with different degrees of CAD severity.

Methods

Serum TGF-β1 and mothers against decapentaplegic homolog 3 (SMAD3) concentrations were evaluated in 279 patients with CAD and 268 controls without CAD. The clinical and biochemical characteristics of all subjects were also determined and analyzed.

Results

TGF-β1 and SMAD3 concentrations in CAD patients were significantly higher than those in the controls. The serum TGF-β1 level in acute myocardial infarction (AMI) was significantly higher than that in both stable angina pectoris (SAP) and unstable angina pectoris (UAP) (p < 0.05), while there was no marked difference between levels in SAP and UAP (p > 0.05). SMAD3 levels showed no obvious difference among AMI, SAP, and UAP. TGF-β1 and SMAD3 are potential biomarkers for CAD, and may be more accurate than Lpa, ApoA1, uric acid, BUN, or triglycerides (TG).

Conclusions

Serum TGF-β1 and SMAD3 levels are closely associated with CAD, and may become useful biomarkers for diagnosis and risk stratification.

Age-dependent defective TGF-beta1 signaling in patients undergoing coronary artery bypass grafting

Background

Transforming growth factor beta (TGF-β1) is a pleiotropic cytokine, which is deregulated in atherosclerosis; however the role of age in this process is unknown. We aimed to assess whether TGF-β1 signaling is affected by age.

Methods

Vascular smooth muscle cells (VSMC) were obtained from patients undergoing abdominal surgery. Levels of TGF-β1 were measured by ELISA in sera from 169 patients undergoing coronary artery bypass grafting (CABG). The p27 expression was determined by Western blot from internal mammary arteries (IMA) obtained from CABG patients (n = 13). In VSMC from these patients undergoing abdominal surgery, secretion of TGF-β1 was determined by ELISA of cell-conditioned media.

Results

In VSMC from aged patients we observed a lower TGF-β1 secretion, measured as TGF-β1 concentration in cell conditioned medium (p < 0.001). This effect was correlated to an age-dependent decrease of p27 expression in IMA from aged CABG patients. In a similar manner, there was an age-dependent decrease of serum TGF-β1 levels in CABG patients (p = 0.0195).

Conclusions

VSMC from aged patients showed a higher degree of cellular senescence and it was associated to a lower TGF-β1 secretion and signaling.

Amyloid-β increases metallo- and cysteine protease activities in human macrophages

BACKGROUND/AIMS

Amyloid-β (Aβ) plays a crucial role in the onset and progression of atherosclerosis. Macrophages are a source of matrix metalloproteinases (MMPs), cysteine proteases and transforming growth factor (TGF)-β1 in the vascular wall. The aims of this study were to analyze the capacity of Aβ peptide (1-40) (Aβ40), Aβ peptide (1-42) (Aβ42) and fibrillar Aβ42 (fAβ42) to modulate the expression and activity of MMP-9, MMP-2 and tissue inhibitor of MMP-1 (TIMP-1) in human monocyte-derived macrophages (HMDM). Additionally, we analyzed whether Aβ internalization alters the secretion of cathepsin S (CatS) and TGF-β1 by macrophages.

METHODS

HMDM were exposed to native and fibrillar Aβ. MMPs and TIMP-1 expression was analyzed by real-time PCR, and MMP abundance by zymography. Protein levels of precursor and active forms of CatS were analyzed by Western blot and TGF-β1 levels by ELISA.

RESULTS

Aβ40, Aβ42 and especially fAβ42 strongly induced MMP-9/MMP-2 levels. Moreover, we showed enhanced active CatS and reduced TGF-β1 protein levels in the secretome of Aβ42 and fAβ42-exposed macrophages.

CONCLUSIONS

Aβ can regulate the proinflammatory state of human macrophages by inducing metallo- and cysteine protease levels and by reducing TGF-β1 secretion. These effects may be crucial in atherosclerosis progression.

T cell-specific overexpression of TGFß1 fails to influence atherosclerosis in ApoE-deficient mice

Clinical data have indicated a negative correlation between plasma TGFß1 concentrations and the extent of atherosclerosis and have thus led to the hypothesis that the pleiotropic cytokine may have anti-atherogenic properties. T-cells are currently discussed to significantly participate in atherogenesis, but the precise role of adaptive immunity in atherogenesis remains to be elucidated. TGFß1 is known to strongly modulate the function of T-cells, however, inhibition of TGFß1 signalling in T-cells of atherosclerosis-prone knock-out mice failed to unequivocally clarify the role of the cytokine for the development of atherosclerosis. In the present study, we thus tried to specify the role of TGFß1 in atherogenesis by using the murine CD2-TGFß1 transgenic strain which represents a well characterized model of T-cell specific TGFß1 overexpression. The CD2-TGFß1 transgenic mice were crossed to ApoE knock-out mice and quantity and quality of atherosclerosis regarding number of macrophages, smooth muscle cells, CD3 positive T-cells and collagen was analyzed in CD2-TGFß1 ApoE double mutants as well as non-transgenic ApoE controls on both normal and atherogenic diet of a duration of 8, 16 or 24 weeks, respectively. In all experimental groups investigated, we failed to detect any influence of TGFß1 overexpression on disease. Total number of CD3-positive T-lymphocytes was not significantly different in atherosclerotic lesions of CD2-TGFß1 ApoE^−/− females and isogenic ApoE^−/− controls, even after 24 weeks on the atherogenic diet. The synopsis of these data and our previous study on TGFß1 overexpressing macrophages suggests that potential effects of TGFß1 on atherosclerosis are most probably mediated by macrophages rather than T-cells.

Overexpression of TGF-ß1 in macrophages reduces and stabilizes atherosclerotic plaques in ApoE-deficient mice

Although macrophages represent the hallmark of both human and murine atherosclerotic lesions and have been shown to express TGF-ß1 (transforming growth factor β1) and its receptors, it has so far not been experimentally addressed whether the pleiotropic cytokine TGF-ß1 may influence atherogenesis by a macrophage specific mechanism. We developed transgenic mice with macrophage specific TGF-ß1 overexpression, crossed the transgenics to the atherosclerotic ApoE (apolipoprotein E) knock-out strain and quantitatively analyzed both atherosclerotic lesion development and composition of the resulting double mutants. Compared with control ApoE^−/− mice, animals with macrophage specific TGF-ß1 overexpression developed significantly less atherosclerosis after 24 weeks on the WTD (Western type diet) as indicated by aortic plaque area en face (p<0.05). Reduced atherosclerotic lesion development was associated with significantly less macrophages (p<0.05 after both 8 and 24 weeks on the WTD), significantly more smooth muscle cells (SMCs; p<0.01 after 24 weeks on the WTD), significantly more collagen (p<0.01 and p<0.05 after 16 and 24 weeks on the WTD, respectively) without significant differences of inner aortic arch intima thickness or the number of total macrophages in the mice pointing to a plaque stabilizing effect of macrophage-specific TGF-ß1 overexpression. Our data shows that macrophage specific TGF-ß1 overexpression reduces and stabilizes atherosclerotic plaques in ApoE-deficient mice.

Cellular growth factors in relation to mortality from cardiovascular disease in middle-aged Japanese: the JACC study

OBJECTIVE

Limited evidence has been available on the relationships of cellular growth factors with cardiovascular disease in population-based samples.

METHODS

We conducted a nested case-control study under a large prospective cohort study (JACC study) where a total of 39,242 subjects aged 40-79 years provided serum sample. We measured cellular growth factors [insulin-like growth factors I, II and binding protein-3 (IGF-I, IGF-II and IGFBP-3) and transforming growth factor (TGF-β1)] among cases and controls, matched for sex, age, area of residence and year of serum storage.

RESULTS AND CONCLUSIONS

During the follow-up for 9 years, there were 233 deaths from total stroke (49 subarachnoid hemorrhages, 55 intraparenchymal hemorrhages, 71 ischemic strokes), and 97 deaths from coronary heart disease. The multivariable odds ratio (95%CI) of intraparenchymal hemorrhage associated with a 1-SD increment of IGF-I (men:4 8 ng/ml, women: 61 ng/ml) was 0.31 (0.14-0.71). That of ischemic stroke associated with a 1-SD increment of TGF-β1 (men: 8.0 ng/ml, women: 10.9 ng/ml) was 0.58 (0.34-0.98). Serum IGF-II and IGFBP-3 were not associated with mortality from any outcomes. In conclusion, IGF-I was inversely associated with mortality from intraparenchymal hemorrhage while TGF-β1 was so with ischemic stroke, suggesting potential roles of cellular proliferation in the development or prognosis of stroke.

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.

Transforming growth factor-β and atherosclerosis: interwoven atherogenic and atheroprotective aspects

Age-related progression of cardiovascular disease is by far the largest health problem in the US and involves vascular damage, progressive vascular fibrosis and the accumulation of lipid-rich atherosclerotic lesions. Advanced lesions can restrict flow to key organs and can trigger occlusive thrombosis resulting in a stroke or myocardial infarction. Transforming growth factor-beta (TGF-β) is a major orchestrator of the fibroproliferative response to tissue damage. In the early stages of repair, TGF-β is released from platelets and activated from matrix reservoirs; it then stimulates the chemotaxis of repair cells, modulates immunity and inflammation and induces matrix production. At later stages, it negatively regulates fibrosis through its strong antiproliferative and apoptotic effects on fibrotic cells. In advanced lesions, TGF-β might be important in arterial calcification, commonly referred to as "hardening of the arteries". Because TGF-β can signal through multiple pathways, namely the SMADs, a MAPK pathway and the Rho/ROCK pathways, selective defects in TGF-β signaling can disrupt otherwise coordinated pathways of tissue regeneration. TGF-β is known to control cell proliferation, cell migration, matrix synthesis, wound contraction, calcification and the immune response, all being major components of the atherosclerotic process. However, many of the effects of TGF-β are essential to normal tissue repair and thus, TGF-β is often thought to be "atheroprotective". The present review attempts to parse systematically the known effects of TGF-β on both the major risk factors for atherosclerosis and to isolate the role of TGF-β in the many component pathways involved in atherogenesis.

Association of transforming growth factor-β1 gene C-509T and T869C polymorphisms with atherosclerotic cerebral infarction in the Chinese: a case-control study

Background

Transforming growth factor-β1 (TGF-β1) is a multifunctional cytokine involved in inflammation and pathogenesis of atherosclerosis. There is scant information on the relation between variations within the TGF-β1 gene polymorphisms and risks of ischemic cerebrovascular diseases. Therefore, this case-controlled study was carried out to investigate the possible association of the TGF-β1 gene C-509T and T869C polymorphisms, and their combined genotypes with the risk of atherosclerotic cerebral infarction (CI) in the Chinese population.

Results

We recruited 164 CI patients and 167 healthy control subjects who were frequency-matched for age and gender. The frequencies of the -509TT genotype and T allele gene were significantly higher in the CI group (P = 0.007, P = 0.006). The frequencies of +869CC genotype and C allele were higher in the CI group (P = 0.002, P = 0.004). In the CI group, the individuals with -509TT genotype had a significantly higher level of plasma triglyceride (TG) (P = 0.017). +869CC genotype correlated significantly with higher level of plasma low density lipoprotein cholesterol (LDL-c) in the CI group (P = 0.015). With haplotype analysis, the frequency of the -509T/+869C combined genotype was significantly higher in the CI group than in controls (P < 0.001).

Conclusions

Our study suggests that C-509T and T869C gene polymorphisms in TGF-β1 may be a critical risk factor of genetic susceptibility to CI in the Chinese population.

TGF-β and restenosis revisited: a Smad link

Despite novel surgical therapies for the treatment of atherosclerosis, restenosis continues to be a significant impediment to the long-term success of vascular interventions. Transforming growth factor-beta (TGF-β), a family of cytokines found to be up-regulated at sites of arterial injury, has long been implicated in restenosis; a role that has largely been attributed to TGF-β-mediated vascular fibrosis. However, emerging data indicate that the role of TGF-β in intimal thickening and arterial remodeling, the critical components of restenosis, is complex and multidirectional. Recent advancements have clarified the basic signaling pathway of TGF-β, making evident the need to redefine the precise role of this family of cytokines and its primary signaling pathway, Smad, in restenosis. Unraveling TGF-β signaling in intimal thickening and arterial remodeling will pave the way for a clearer understanding of restenosis and the development of innovative pharmacological therapies.

TGF-β1 869T/C polymorphism and ischemic stroke: sex difference in Chinese

BACKGROUND

Inflammation plays a pivotal role in the pathogenesis of atherosclerosis and of cerebrovascular complications. Transforming growth factor-β (TGF-β) is a pleiotropic cytokine with a central role in inflammation. To investigate whether polymorphisms of the TGF-β1 gene can modify the risk of ischemic stroke (IS) in Chinese population, we conduct this hospital-based, case-control study.

METHODS

Transforming growth factor-β1 genotype was determined in 450 Chinese patients (306 male and 144 female) with IS and 450 control subjects (326 male and 124 female).

RESULTS

Subjects carrying 869TT were susceptible to IS (odds ratio [OR] =1.58; P=0.003). Further analysis of IS data partitioned by gender revealed the female-specific association with 869T/C (OR=2.64; P=0.001).

CONCLUSIONS

Findings suggest that the TT genotype of 869T/C might be a risk factor of IS in Chinese, especially in females.

Transforming Growth Factor-β1 as a Common Target Molecule for Development of Cardiovascular Diseases, Renal Insufficiency and Metabolic Syndrome

Transforming growth factor-β1 (TGF-β1) is a polypeptide member of the transforming growth factor β superfamily of cytokines. It is a secreted protein that performs many cellular functions including control of cell growth, cell proliferation, cell differentiation and apoptosis. In the cardiovascular system, TGF-β1 plays pivotal roles in the pathogenesis of hypertension, restenosis after percutaneous coronary intervention, atherosclerosis, cardiac hypertrophy and heart failure. In addition, TGF-β1 has been shown to be increased in adipose tissue of obese subjects with insulin resistance. Furthermore, TGF-β1 is a potent initiator of proliferation of renal mesangial cells leading to chronic kidney disease. Some currently available agents can manipulate TGF-β1 expression leading to amelioration of cardiovascular diseases. Thus, an understanding of interactions between chronic kidney disease and metabolic syndrome and the development of cardiovascular diseases is an important issue, and attention should be given to TGF-β1 as a crucial factor for regulation and modulation of those pathological conditions.

TGF-[beta]1 limits plaque growth, stabilizes plaque structure, and prevents aortic dilation in apolipoprotein E-null mice

OBJECTIVE

Impairment of transforming growth factor (TGF)-beta1 signaling accelerates atherosclerosis in experimental mice. However, it is uncertain whether increased TGF-beta1 expression would retard atherosclerosis. The role of TGF-beta1 in aneurysm formation is also controversial. We tested whether overexpression of active TGF-beta1 in hyperlipidemic mice affects atherogenesis and aortic dilation.

METHODS AND RESULTS

We generated apolipoprotein E-null mice with transgenes that allow regulated overexpression of active TGF-beta1 in their hearts. Compared to littermate controls, these mice had elevated cardiac and plasma TGF-beta1, less aortic root atherosclerosis (P< or =0.002), fewer lesions in the thoracic and abdominal aortae (P< or =0.01), less aortic root dilation (P<0.001), and fewer pseudoaneurysms (P=0.02). Mechanistic studies revealed no effect of TGF-beta1 overexpression on plasma lipids or cytokines, or on peripheral lymphoid organ cells. However, aortae of TGF-beta1-overexpressing mice had fewer T-lymphocytes, more collagen, less lipid, lower expression of inflammatory cytokines and matrix metalloproteinase-13, and higher expression of tissue inhibitor of metalloproteinase-2.

CONCLUSIONS

When overexpressed in the heart and plasma, TGF-beta1 is an antiatherogenic, vasculoprotective cytokine that limits atherosclerosis and prevents aortic dilation. These actions are associated with significant changes in cellularity, collagen and lipid accumulation, and gene expression in the artery wall.

Fibrosis in diabetes complications: pathogenic mechanisms and circulating and urinary markers

Diabetes mellitus is characterized by a lack of insulin causing elevated blood glucose, often with associated insulin resistance. Over time, especially in genetically susceptible individuals, such chronic hyperglycemia can cause tissue injury. One pathological response to tissue injury is the development of fibrosis, which involves predominant extracellular matrix (ECM) accumulation. The main factors that regulate ECM in diabetes are thought to be pro-sclerotic cytokines and protease/anti-protease systems. This review will examine the key markers and regulators of tissue fibrosis in diabetes and whether their levels in biological fluids may have clinical utility.

Elevated serum soluble endoglin (sCD105) decreased during extracorporeal elimination therapy for familial hypercholesterolemia

Extracorporeal elimination is a method of LDL-lowering therapy that is used in severe familial hypercholesterolemia (FH) after other therapeutic approaches have failed. There are currently no universally accepted biomarkers that would allow determining necessary intensity of therapy and frequency of future therapeutic interventions. An ideal tool for immediate evaluation would be a readily measurable serum marker. We hypothesized that soluble endoglin (sCD105), a recently described indicator of endothelial dysfunction, may represent such a tool. Eleven patients with FH (three homozygous, eight heterozygous; Fredrickson type IIa, IIb) that have been monitored for 4.5+/-2.8 years were treated; eight by LDL-apheresis and three by hemorheopheresis. 40 sCD105 measurements were done, before and after two consecutive elimination procedures. Baseline serum sCD105 levels were significantly higher in the patients (5.74+/-1.47 microg/l in series I, 6.85+/-1.85 microg/l in series II) than in the control group (3.85+/-1.25 microg/l). They decreased to normal after LDL-elimination (p=0.0003) in all except for one patient. This return to normal was not due to a non-specific capture of endoglin in adsorption or filtration columns as demonstrated by measurement of sCD105 before and after passage through the elimination media. We conclude that the soluble endoglin levels in patients with severe FH remain elevated despite long-term intensive therapy and that they decrease after extracorporeal elimination. Endoglin can therefore serve as a marker for evaluation of the treatment efficacy and of the decreased atherosclerotic activity in patients with FH treated by extracorporeal LDL-cholesterol elimination.

Role of transforming growth factor-beta superfamily signaling pathways in human disease

Transforming growth factor beta (TGF-beta) superfamily signaling pathways are ubiquitous and essential regulators of cellular processes including proliferation, differentiation, migration, and survival, as well as physiological processes, including embryonic development, angiogenesis, and wound healing. Alterations in these pathways, including either germ-line or somatic mutations or alterations in the expression of members of these signaling pathways often result in human disease. Appropriate regulation of these pathways is required at all levels, particularly at the ligand level, with either a deficiency or an excess of specific TGF-beta superfamily ligands resulting in human disease. TGF-beta superfamily ligands and members of these TGF-beta superfamily signaling pathways also have emerging roles as diagnostic, prognostic or predictive markers for human disease. Ongoing studies will enable targeting of TGF-beta superfamily signaling pathways for the chemoprevention and treatment of human disease.

'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-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.

TGF-beta1 generates a specific multicomponent extracellular matrix in human coronary SMC

BACKGROUND

Transforming growth factor (TGF-beta(1)) is postulated to play an important role in maintaining the structure and function of arterial tissue and protection against development of arteriosclerosis. The TGF-beta(1)-induced production of a stable extra-cellular matrix-rich plaque phenotype is suggested to be part of the protection against a switch to an unstable rupture-prone arteriosclerotic plaque.

MATERIALS AND METHODS

This study addresses the question of whether the expression profile and the type of extra-cellular matrix (ECM) generated by TGF-beta(1) stimulation have the structural feature of a fibril-rich stable matrix. Seventeen genes codings for ECM components of human coronary smooth muscle cells (SMCs) after a 24-h stimulation by TGF-beta(1) have been analyzed.

RESULTS

Real-time RT-PCR was used to quantify the mRNA of genes under investigation. It was found that after TGF-beta(1) stimulation (a) the up-regulation of COL1A1-specific mRNA was associated with increased [(3)H]proline incorporation into the alpha-1 and -2 chains of collagen type I, (b) the up-regulation of biglycan- and syndecan-1-specific mRNA corresponded to an increased [(35)S]sulphate and [4,5-(3)H]leucine incorporation into the biglycan molecule and to an increase of syndecan-1 protein, (c) the up-regulated FGF-2 gene accounted predominantly for the ECM-bound subfraction of FGF-2-protein and (d) fibronectin and thrombospondin exhibited a significantly higher mRNA level. In contrast collagen XIV, a minor collagen type, and the proteoglycan decorin were down-regulated. The down-regulated decorin changed its structure by elongation and reduced GlcA to IdoA epimerization of the dermatan sulphate side-chain as judged by [(35)S]sulphate metabolic labelling experiments. No significant changes in response to TGF-beta(1) were observed for the collagen types III, VI and XVI, for versican, perlecan and the syndecans-2 and -4.

CONCLUSIONS

It was concluded from the data that the TGF-beta(1)-induced formation of a highly specific multicomponent extra-cellular matrix on coronary arterial SMCs could provide in vivo mechanical strength to the neointima in arteriosclerotic lesions and to the fibrous cap overlying the lipid core.

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.

Different effects of simvastatin and losartan on cytokine levels in coronary artery disease

BACKGROUND AND OBJECTIVE

Use of HMG-CoA reductase inhibitors (statins) and angiotensin II type 1 (AT(1)) receptor antagonists reduces the incidence of cardiovascular events. The cytokines macrophage colony-stimulating factor (M-CSF) and transforming growth factor (TGF)-beta may exert proatherogenic and antiatherogenic effects, respectively. In this study, we examined whether treatment with a statin or an AT(1) receptor antagonist alters M-CSF and TGF-beta levels in patients with coronary artery disease.

METHODS

Twenty-seven consecutive patients with coronary artery disease were randomly assigned to the following three treatment groups for 8 weeks: simvastatin 5 mg/day (n = 10); losartan 50 mg/day (n = 9); or control (usual treatment; n = 8). Blood samples were collected before and after treatment.

RESULTS

Clinical characteristics and baseline cytokine levels were comparable among the three groups. Serum levels of M-CSF were significantly decreased only in the simvastatin group (from 403 +/- 71 to 303 +/- 116 pg/mL; p = 0.009). Plasma levels of TGF-beta were significantly increased only in the losartan group (from 5.01 +/- 1.13 to 7.50 +/- 3.83 ng/mL; p = 0.021). Simvastatin decreased serum M-CSF levels independently of changes in total cholesterol or low-density lipoprotein-cholesterol.

CONCLUSIONS

The results of this study indicate that simvastatin decreases serum levels of M-CSF while losartan increases plasma levels of TGF-beta, suggesting that the two drugs may have different anti-atherosclerotic properties.

Effects of moderate Sicilian red wine consumption on inflammatory biomarkers of atherosclerosis

OBJECTIVE

The aim of the study is to evaluate the effect of moderate Sicilian red wine consumption on cardiovascular risk factors and, in particular, on some inflammatory biomarkers.

METHODS

A total of 48 subjects of both sexes who were nondrinkers or rare drinkers of moderate red wine were selected and randomly subdivided into two groups assigned to receive with a crossover design a Sicilian red wine (Nero d'Avola or Etna Torrepalino) during meals: Group A (n = 24), in whom the diet was supplemented for 4 weeks with 250 ml/day of red wine, followed by 4 weeks when they returned to their usual wine intake; and Group B (n = 24), in whom the usual wine intake was maintained for 4 weeks, followed by 4 weeks when the diet was supplemented with 250 ml/day of red wine. The following were values measured in all tests: blood glucose, total and HDL-cholesterol and triglycerides, LDL-cholesterol, LDL/HDL ratio, apolipoproteins A1 and B, Lp(a), plasma C-reactive protein, TGFbeta1, D-Dimer, Factor VII , PAl Ag, t-PA Ag, fibrinogen, oxidized LDL Ab, total plasma antioxidant capacity.

RESULTS

At the end of the red wine intake period, LDL/HDL, fibrinogen, factor VII, plasma C-reactive protein and oxidized LDL Ab were significantly decreased, while HDL-C, Apo A1,TGFbeta1, t-PA, PAI and total plasma antioxidant capacity were significantly increased.

CONCLUSIONS

Our results show a positive effect of two Sicilian red wines on many risk factors and on some inflammatory biomarkers, suggesting that a moderate consumption of red wine in the adult population is a positive component of the Mediterranean diet.

Candidate-based proteomics in the search for biomarkers of cardiovascular disease

The key concept of proteomics (looking at many proteins at once) opens new avenues in the search for clinically useful biomarkers of disease, treatment response and ageing. As the number of proteins that can be detected in plasma or serum (the primary clinical diagnostic samples) increases towards 1000, a paradoxical decline has occurred in the number of new protein markers approved for diagnostic use in clinical laboratories. This review explores the limitations of current proteomics protein discovery platforms, and proposes an alternative approach, applicable to a range of biological/physiological problems, in which quantitative mass spectrometric methods developed for analytical chemistry are employed to measure limited sets of candidate markers in large sets of clinical samples. A set of 177 candidate biomarker proteins with reported associations to cardiovascular disease and stroke are presented as a starting point for such a 'directed proteomics' approach.

Atherosclerotic plaque rupture: local or systemic process?

It is generally established that the unstable plaque is the major cause of acute clinical sequelae of atherosclerosis. Unfortunately, terms indicating lesions prone to plaque instability, such as "vulnerable plaque," and the different phenotypes of unstable plaques, such as plaque rupture, plaque fissuring, intraplaque hemorrhage, and erosion, are often used interchangeably. Moreover, the different phenotypes of the unstable plaque are mostly referred to as plaque rupture. In the first part of this review, we will focus on the definition of true plaque rupture and the definitions of other phenotypes of plaque instability, especially on intraplaque hemorrhage, and discuss the phenotypes of available animal models of plaque instability. The second part of this review will address the pathogenesis of plaque rupture from a local and a systemic perspective. Plaque rupture is thought to occur because of changes in the plaque itself or systemic changes in the patient. Interestingly, contributing factors seem to overlap to a great extent and might even be interrelated. Finally, we will propose an integrative view on the pathogenesis of plaque rupture.

TGF-beta 1 attenuates myocardial ischemia-reperfusion injury via inhibition of upregulation of MMP-1

Ischemia-reperfusion (I/R) is thought to upregulate the expression and activity of matrix metalloproteinases (MMPs), which regulate myocardial and vascular remodeling. Previous studies have shown that transforming growth factor-beta(1) (TGF-beta(1)) can attenuate myocardial injury induced by I/R. TGF-beta(1) is also reported to suppress the release of MMPs. To study the modulation of MMP-1 by TGF-beta(1) in I/R myocardium, Sprague-Dawley rats were given saline and subjected to 1 h of myocardial ischemia [total left coronary artery (LCA) ligation] followed by 1 h of reperfusion (n = 9). Parallel groups of rats were pretreated with recombinant TGF-beta(1) (rTGF-beta(1), 1 mg/rat, n = 9) before reperfusion or exposure to sham I/R (control group). I/R caused myocardial necrosis and dysfunction, indicated by decreased first derivative of left ventricular pressure, mean arterial blood pressure, and heart rate (all P < 0.01 vs. sham-operated control group). Simultaneously, I/R upregulated MMP-1 (P < 0.01). Treatment of rats with rTGF-beta(1) reduced the extent of myocardial necrosis and dysfunction despite I/R (all P < 0.01). rTGF-beta(1) treatment also inhibited the upregulation of MMP-1 in the I/R myocardium (P < 0.05). To determine the direct effect of MMP-1 on the myocardium, isolated adult rat myocytes were treated with active MMP-1, which caused injury and death of cultured myocytes, measured as lactate dehydrogenase release and trypan blue staining, in a dose- and time-dependent manner (P < 0.05). Pretreatment with PD-166793, a specific MMP inhibitor, attenuated myocardial injury and death induced by active MMP-1. The present study for the first time shows that MMP-1 can directly cause myocyte injury or death and that attenuation of myocardial I/R injury by TGF-beta(1) may, at least partly, be mediated by the inhibition of upregulation of MMP-1.