Acute myocardial infarction leads to acceleration of atherosclerosis

α1A Adrenoreceptor blockade attenuates myocardial infarction by modulating the integrin-linked kinase/TGF-β/Smad signaling pathways

Background

Myocardial infarction (MI) is considered a public health problem. According to the World Health Organization, MI is a leading cause of death and comorbidities worldwide. Activation of the α1A adrenergic receptor is a contributing factor to the development of MI. Tamsulosin, an α1A adrenergic blocker, has gained wide popularity as a medication for the treatment of benign prostatic hyperplasia. Limited evidence from previous studies has revealed the potential cardioprotective effects of tamsulosin, as its inhibitory effect on the α1A adrenoceptor protects the heart by acting on the smooth muscle of blood vessels, which results in hypotension; however, its effect on the infarcted heart is still unclear. The mechanisms of the expected cardioprotective effects mediated by tamsulosin are not yet understood. Transforming growth factor-beta (TGF-β), a mediator of fibrosis, is considered an attractive therapeutic target for remodeling after MI. The role of α1A adrenoceptor inhibition or its relationships with integrin-linked kinase (ILK) and TGF-β/small mothers against decapentaplegic (Smad) signaling pathways in attenuating MI are unclear. The present study was designed to investigate whether tamsulosin attenuates MI by modulating an ILK-related TGF-β/Smad pathway.

Methods

Twenty-four adult male Wistar rats were randomly divided into 4 groups: control, ISO, TAM, and ISO + TAM. ISO (150 mg/kg, intraperitoneally) was injected on Days 20 and 21 to induce MI. Tamsulosin (0.8 mg/kg, orally) was administered for 21 days, prior to ISO injection for 2 consecutive days. Heart-to-body weight ratios and cardiac and fibrotic biomarker levels were subsequently determined. ILK, TGF-β1, p-Smad2/3, and collagen III protein expression levels were determined using biomolecular methods.

Results

Tamsulosin significantly attenuated the relative heart-to-body weight index (p < 0.5) and creatine kinase-MB level (p < 0.01) compared with those in the ISO control group. While ISO resulted in superoxide anion production and enhanced oxidative damage, tamsulosin significantly prevented this damage through antioxidant defense mechanisms, increasing glutathione and superoxide dismutase levels (p < 0.05) and decreasing lipid peroxide oxidation levels (p < 0.01). The present data revealed that tamsulosin reduced TGF-β/p-Smad2/3 expression and enhanced ILK expression.

Conclusion

Tamsulosin may exert a cardioprotective effect by modulating the ILK-related TGF-β/Smad signaling pathway. Thus, tamsulosin may be a useful therapeutic approach for preventing MI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-023-03188-w.

Blood Milieu in Acute Myocardial Infarction Reprograms Human Macrophages for Trauma Repair

Acute myocardial infarction (AMI) is accompanied by a systemic trauma response that impacts the whole body, including blood. This study addresses whether macrophages, key players in trauma repair, sense and respond to these changes. For this, healthy human monocyte-derived macrophages are exposed to 20% human AMI (n = 50) or control (n = 20) serum and analyzed by transcriptional and multiparameter functional screening followed by network-guided data interpretation and drug repurposing. Results are validated in an independent cohort at functional level (n = 47 AMI, n = 25 control) and in a public dataset. AMI serum exposure results in an overt AMI signature, enriched in debris cleaning, mitosis, and immune pathways. Moreover, gene networks associated with AMI and with poor clinical prognosis in AMI are identified. Network-guided drug screening on the latter unveils prostaglandin E2 (PGE2) signaling as target for clinical intervention in detrimental macrophage imprinting during AMI trauma healing. The results demonstrate pronounced context-induced macrophage reprogramming by the AMI systemic environment, to a degree decisive for patient prognosis. This offers new opportunities for targeted intervention and optimized cardiovascular disease risk management.

Systemic Vulnerability, as Expressed by I-CAM and MMP-9 at Presentation, Predicts One Year Outcomes in Patients with Acute Myocardial Infarction-Insights from the VIP Clinical Study

(1) Background: The prediction of recurrent events after acute myocardial infarction (AMI) does not sufficiently integrate systemic inflammation, coronary morphology or ventricular function in prediction algorithms. We aimed to evaluate the accuracy of inflammatory biomarkers, in association with angiographical and echocardiographic parameters, in predicting 1-year MACE after revascularized AMI. (2) Methods: This is an extension of a biomarker sub-study of the VIP trial (NCT03606330), in which 225 AMI patients underwent analysis of systemic vulnerability and were followed for 1 year. Hs-CRP, MMP-9, IL-6, I-CAM, V-CAM and E-selectin were determined at 1 h after revascularization. The primary end-point was the 1-year MACE rate. (3) Results: The MACE rate was 24.8% (n = 56). There were no significant differences between groups in regard to IL-6, V-CAM and E-selectin. The following inflammatory markers were significantly higher in MACE patients: hs-CRP (11.1 ± 13.8 vs. 5.1 ± 4.4 mg/L, p = 0.03), I-CAM (452 ± 283 vs. 220.5 ± 104.6, p = 0.0003) and MMP-9 (2255 ± 1226 vs. 1099 ± 706.1 ng/mL p = 0.0001). The most powerful predictor for MACE was MMP-9 of >1155 ng/mL (AUC-0.786, p < 0.001) even after adjustments for diabetes, LVEF, acute phase complications and other inflammatory biomarkers. For STEMI, the most powerful predictors for MACE included I-CAM > 239.7 ng/mL, V-CAM > 877.9 ng/mL and MMP-9 > 1393 ng/mL. (4) Conclusions: High levels of I-CAM and MMP-9 were the most powerful predictors for recurrent events after AMI for the overall study population. For STEMI subjects, the most important predictors included increased levels of I-CAM, V-CAM and MMP-9, while none of the analyzed parameters had proven to be predictive. Inflammatory biomarkers assayed during the acute phase of AMI presented a more powerful predictive capacity for MACE than the LVEF.

Screening and identification of potential protein biomarkers for the early diagnosis of acute myocardial infarction

Background

Acute myocardial infarction (AMI) is the most serious type of heart disease. Clinically, there is an urgent need to discover diagnostic biomarkers for the early diagnosis of AMI.

Methods

Serum proteomic profiles in AMI patients, healthy controls, and stable angina pectoris (SAP) patients were explored and compared by iTRAQ-2DLC-MS/MS. The clinical data of AMI patients were also analyzed. Differentially expressed proteins were validated by enzyme linked immunosorbent assay (ELISA), and diagnostic models were constructed.

Results

A total of 39 differentially expressed proteins were identified in AMI patients. The results showed that the serum levels of apolipoprotein E (APOE) in AMI patients were notably higher than those in the healthy controls (P=0.0172). The serum levels of aspartate aminotransferase (AATC) in AMI patients were markedly higher than those in the healthy controls and SAP patients (P<0.0001 and P<0.0001, respectively). The serum levels of fibronectin (FINC) in SAP patients were significantly higher than those in the healthy controls and AMI patients (P=0.0043 and P=0.0044, respectively). Clinical data analysis showed a considerable difference in blood glucose levels, troponin I (TNI), and creatine kinase (CK) in AMI patients compared with SAP patients and healthy controls. A diagnostic model consisting of AATC and clinical indicators [lactate dehydrogenase (LDH) and CK] was established to distinguish between AMI patients and healthy controls, with an area under the curve (AUC) value of 0.993 sensitivity and specificity of 96.2% and 96.3%, respectively. A diagnostic model consisting of AATC and CK was established to distinguish between AMI patients and SAP patients, with an AUC value of 0.975 and a sensitivity and specificity of 85.2% and 79.30%, respectively.

Conclusions

In this study, differentially expressed proteins in AMI patients were combined with clinical indexes, LDH and CK, and two diagnostic models were constructed. This study may provide meaningful data for the early diagnosis of AMI.

Five-Year Risk of Acute Myocardial Infarction After Acute Ischemic Stroke in Korea

Background

The long‐term incidence of acute myocardial infarction (AMI) in patients with acute ischemic stroke (AIS) has not been well defined in large cohort studies of various race‐ethnic groups.

Methods and Results

A prospective cohort of patients with AIS who were registered in a multicenter nationwide stroke registry (CRCS‐K [Clinical Research Collaboration for Stroke in Korea] registry) was followed up for the occurrence of AMI through a linkage with the National Health Insurance Service claims database. The 5‐year cumulative incidence and annual risk were estimated according to predefined demographic subgroups, stroke subtypes, a history of coronary heart disease (CHD), and known risk factors of CHD. A total of 11 720 patients with AIS were studied. The 5‐year cumulative incidence of AMI was 2.0%. The annual risk was highest in the first year after the index event (1.1%), followed by a much lower annual risk in the second to fifth years (between 0.16% and 0.27%). Among subgroups, annual risk in the first year was highest in those with a history of CHD (4.1%) compared with those without a history of CHD (0.8%). The small‐vessel occlusion subtype had a much lower incidence (0.8%) compared with large‐vessel occlusion (2.2%) or cardioembolism (2.4%) subtypes. In the multivariable analysis, history of CHD (hazard ratio, 2.84; 95% CI, 2.01–3.93) was the strongest independent predictor of AMI after AIS.

Conclusions

The incidence of AMI after AIS in South Korea was relatively low and unexpectedly highest during the first year after stroke. CHD was the most substantial risk factor for AMI after stroke and conferred an approximate 5‐fold greater risk.

Microvesicles (MIVs) secreted from adipose-derived stem cells (ADSCs) contain multiple microRNAs and promote the migration and invasion of endothelial cells

Extracellular vesicles (EVs) such as microvesicles (MIVs) play an important role in intercellular communications. MIVs are small membrane vesicles sized 100–1000 nm in diameter that are released by many types of cells, such as mesenchymal stem cells (MSCs), tumor cells and adipose-derived stem cells (ADSC). As EVs can carry out autocrine and paracrine functions by controlling multiple cell processes, it is conceivable that EVs can be used as delivery vehicles for treating several clinical conditions, such as to improve cardiac angiogenesis after myocardial infarction (MI). Here, we seek to investigate whether ADSC-derived MIVs contain microRNAs that regulate angiogenesis and affect cell migration of endothelial cells. We first characterized the ADSC-derived MIVs and found that the MIVs had a size range of 100–300 nm, and expressed the MIV marker protein Alix. We then analyzed the microRNAs in ADSCs and ADSC-derived MIVs and demonstrated that ADSC-derived MIVs selectively released a panel of microRNAs, several of which were related to angiogenesis, including two members of the let-7 family. Furthermore, we demonstrated that ADSC-derived MIVs promoted the cell migration and invasion of the HUVEC endothelial cells. The PKH26-labeled ADSC-derived MIVs were effectively uptaken into the cytoplasm of HUVEC cells. Collectively, our results demonstrate that the ADSC-derived MIVs can promote migration and invasion abilities of endothelial cells, suggesting pro-angiogenetic potential. Future studies should focus on investigating the roles and mechanisms through which ADSC-derived MIVs regulate angiogenesis.

Evaluation of stent length on the outcome of ST-segment elevation myocardial infarction receiving primary percutaneous coronary intervention

BACKGROUND

A longer stent length is known to be a predictor of adverse events after a percutaneous coronary intervention (PCI). However, the evaluation of the stent length on the outcome of ST-segment elevation myocardial infarction (STEMI) patients is not enough.

PATIENTS AND METHODS

A total of 686 STEMI patients who underwent primary PCI were divided into four groups according to the total stent length as follows: short (<18 mm, n=183), lower-medium (18-23 mm, n=256), upper-medium (24-31 mm, n=155), and long (≥32 mm, n=92). We compared the all-cause mortality, major adverse cardiovascular events (MACEs; composite of cardiovascular death, myocardial infarction, and stroke after discharge), target lesion revascularization, and target vessel revascularization with a median follow-up of 1213 days among these four groups.

RESULTS

There were no significant differences in MACEs (10.4% in the short, 7.0% in the lower-medium, 6.5% in the upper-medium, 7.6% in the long, P=0.633) among the different stent length groups. The all-cause mortality, target lesion revascularization, and target vessel revascularization also did not differ among the four groups. In the drug-eluting stent (n=237) and bare-metal stent subgroups (n=449), all outcomes were comparable among the groups. However, in the diabetes subgroup (n=265), the rate of MACEs was higher in the long group than in the other groups, although the difference was not significant (6.6% in the short, 9.6% in the lower-medium, 3.4% in upper-medium, 16.7% in long group, P=0.095).

CONCLUSION

A long stent length was not associated with adverse clinical outcomes in STEMI patients who underwent primary PCI.

TIPE2 suppresses atherosclerosis by exerting a protective effect on macrophages via the inhibition of the Akt signaling pathway

Macrophage apoptosis and inflammation serve pivotal roles in the occurrence of atherosclerosis. However, the detailed underlying mechanism of macrophage action during atherosclerosis is poorly understood. Tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) is a well-known negative regulator of the immune response. The current study assessed the association between TIPE2 and apoptosis-associated molecules in macrophages during atherosclerosis, as well as the role of TIPE2 in macrophage inflammation. RAW264.7 macrophages were subsequently transfected with a TIPE2 expression plasmid. Following oxidized low-density lipoprotein (oxLDL) induction (100 µg/m1) for 48 h, macrophage apoptosis was assessed via Annexin V/propidium iodide dual staining. The apoptosis-associated factors and Akt signaling pathway-associated factors were also evaluated via western blot analysis. The expression of inflammatory factors was determined via a reverse transcription-quantitative polymerase chain reaction assay and western blotting. Furthermore, a transwell assay was performed to test cell invasion ability. NF-κB phosphorylation and nuclear translocation were also assessed via western blotting. The results demonstrated that TIPE2 overexpression may promote oxLDL-induced RAW264.7 macrophage apoptosis by inhibiting the protein kinase B (Akt) signaling pathway. Furthermore, it was demonstrated that TIPE2 significantly reduced oxLDL-induced tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein 1 expression (MCP-1), and increased IL-10 expression by suppressing NF-κB phosphorylation and nuclear translocation in RAW264.7 macrophages. These results indicated that TIPE2 serves a protective role in oxLDL-induced RAW264.7 macrophages, and its mechanism may partly be exerted via the inhibition of the PI3K/Akt signaling pathway and the reduction of the macrophage inflammatory response achieved via the suppression of NF-κB signal activation.

Inflammatory Response During Myocardial Infarction

The occlusion of a coronary artery by a thrombus generated on a ruptured atherosclerotic plaque has been pursued in the last decades as a determining event for the clinical outcome after myocardial infarction (MI). Yet, MI causes a cell death wave front, which triggers an inflammatory response to clear cellular debris, and which in excess can double the myocardial lesion and influence the clinical prognosis in the short and long term. Accordingly, proper, timely regulated inflammatory response has now been considered a second pivotal player in cardiac recovery after MI justifying the search for pharmacological strategies to modulate inflammatory effectors. This chapter reviews the key events and the main effectors of inflammation after myocardial ischemic insult, as well as the contribution of this phenomenon to the progression of atherosclerosis.

Assessing Risk in Patients with Stable Coronary Disease: When Should We Intensify Care and Follow-Up? Results from a Meta-Analysis of Observational Studies of the COURAGE and FAME Era

Background. A large number of clinical and laboratory markers have been appraised to predict prognosis in patients with stable angina, but uncertainty remains regarding which variables are the best predictors of prognosis. Therefore, we performed a meta-analysis of studies in patients with stable angina to assess which variables predict prognosis. Methods. MEDLINE and PubMed were searched for eligible studies published up to 2015, reporting multivariate predictors of major adverse cardiac events (MACE, a composite endpoint of death, myocardial infarction, and revascularization) in patients with stable angina. Study features, patient characteristics, and prevalence and predictors of such events were abstracted and pooled with random-effect methods (95% CIs). Major adverse cardiovascular event (MACE) was the primary endpoint. Results. 42 studies (104,559 patients) were included. After a median follow-up of 57 months, cardiovascular events occurred in 7.8% of patients with MI in 6.2% of patients and need for repeat revascularization (both surgical and percutaneous) in 19.5% of patients. Male sex, reduced EF, diabetes, prior MI, and high C-reactive protein were the most powerful predictors of cardiovascular events. Conclusions. We show that simple and low-cost clinical features may help clinicians in identifying the most appropriate diagnostic and therapeutic approaches within the broad range of outpatients presenting with stable coronary artery disease.

Natriuretic peptides, nitrite/nitrate and superoxide dismutase have additional value on top of the GRACE score in prediction of one-year mortality and rehospitalisation for heart failure in STEMI patients - Multiple biomarkers prospective cohort study

BACKGROUND

Blood-based biomarkers have a prognostic value in patients with myocardial infarction. The aim of our prospective observational cohort study was to evaluate the prognostic value of biomarkers of different pathophysiological pathways for the occurrence of 1-year all-cause mortality and hospitalisation due to acute heart failure.

METHODS AND RESULTS

In 593 patients with ST-segment elevation MI (STEMI) treated by primary PCI, biomarkers were evaluated at 24h after MI onset. A minimum of three-year follow-up was achieved in all patients. The combination of 1-year all-cause mortality and hospitalisation due to heart failure was the primary endpoint. A cohort for validation of our combined GRACE-natriuretic peptide (NP) score included 667 STEMI patients. The primary endpoint was reached in 9.3% of patients. Among 21 biomarkers, only B-type natriuretic peptide (BNP), NT-proBNP, superoxide dismutase and nitrite/nitrate, added to clinical GRACE score led to a significant increase in the area under the curve of C statistics, in comparison to GRACE alone (tested by Delong's test). Continuous net reclassification improvement and integrated discrimination index demonstrated an improved reclassification and discrimination of the GRACE model for SOD, BNP and NT-proBNP, and improved reclassification for nitrite/nitrate. Consistent results for this new combined prognostic model GRACE-NP were found also for a validation cohort.

CONCLUSIONS

The levels of NP have an additional value to the prognostic properties of the GRACE score for the prediction of the combined endpoint of one-year mortality or hospitalisation for AHF. Nitrite/nitrate and SOD are strong prognostic factors, even on top of the GRACE score.

Changes of coronary plaque composition correlate with C-reactive protein levels in patients with ST-elevation myocardial infarction following high-intensity statin therapy

OBJECTIVES

Levels of inflammatory biomarkers associate with changes of coronary atheroma burden in statin-treated patients with stable coronary artery disease. This study sought to determine changes of plaque composition in vivo in relation to high-sensitivity C-reactive protein (hs-CRP) levels in patients with ST-elevation myocardial infarction (STEMI) receiving high-intensity statin therapy.

METHODS

The IBIS-4 study performed serial (baseline and 13-month), 2-vessel intravascular ultrasound (IVUS) and radiofrequency-IVUS of the non-infarct-related arteries in patients with STEMI treated with high-intensity statin therapy. The present analysis included 44 patients (80 arteries) with serial measurements of hs-CRP.

RESULTS

At follow-up, median low-density lipoprotein cholesterol (LDL-C) levels decreased from 126 to 77 mg/dl, HDL-C increased from 44 to 47 mg/dl, and hs-CRP decreased from 1.6 to 0.7 mg/L. Regression of percent atheroma volume (-0.99%, 95% CI -1.84 to -0.14, p = 0.024) was accompanied by reduction of percent fibro-fatty (p = 0.04) and fibrous tissue (p < 0.001), and increase in percent necrotic core (p = 0.006) and dense calcium (p < 0.001). Follow-up levels of hs-CRP, but not LDL-C, correlated with changes in percent necrotic core (p = 0.001) and inversely with percent fibrous tissue volume (p = 0.008). Similarly, baseline-to-follow-up change of hs-CRP correlated with the change in percent necrotic core volume (p = 0.02).

CONCLUSIONS

In STEMI patients receiving high-intensity statin therapy, stabilization of VH-IVUS-defined necrotic core was confined to patients with lowest on-treatment levels and greatest reduction of hs-CRP. Elevated CRP levels at follow-up may identify progression of high-risk coronary plaque composition despite intensive statin therapy and overall regression of atheroma volume.

In vivo MR and Fluorescence Dual-modality Imaging of Atherosclerosis Characteristics in Mice Using Profilin-1 Targeted Magnetic Nanoparticles

Aims: This study aims to explore non-invasive imaging of atherosclerotic plaque through magnetic resonance imaging (MRI) and near-infrared fluorescence (NIRF) by using profilin-1 targeted magnetic iron oxide nanoparticles (PF₁-Cy5.5-DMSA-Fe₃O₄-NPs, denoted as PC-NPs) as multimodality molecular imaging probe in murine model of atherosclerosis. Methods and Results: PC-NPs were constructed by conjugating polyclonal profilin-1 antibody and NHS-Cy5.5 fluorescent dye to the surface of DMSA-Fe₃O₄-nanoparticles via condensation reaction. Murine atherosclerosis model was induced in apoE^-/- mice by high fat and cholesterol diet (HFD) for 16 weeks. The plaque areas in aortic artery were detected with Oil Red O staining. Immunofluorescent staining and Western blot analysis were applied respectively to investigate profilin-1 expression. CCK-8 assay and transwell migration experiment were performed to detect vascular smooth muscle cells (VSMCs) proliferation. In vivo MRI and NIRF imaging of atherosclerotic plaque were carried out before and 36 h after intravenous injection of PC-NPs. Oil Red O staining showed that the plaque area was significantly increased in HFD group (p<0.05). Immunofluorescence staining revealed that profilin-1 protein was highly abundant within plaque in HFD group and co-localized with α-smooth muscle actin. Profilin-1 siRNA intervention could inhibit VSMCs proliferation and migration elicited by ox-LDL (p<0.05). In vivo MRI and NIRF imaging revealed that PC-NPs accumulated in atherosclerotic plaque of carotid artery. There was a good correlation between the signals of MRI and ex vivo fluorescence intensities of NIRF imaging in animals with PC-NPs injection. Conclusion: PC-NPs is a promising dual modality imaging probe, which may improve molecular diagnosis of plaque characteristics and evaluation of pharmaceutical interventions for atherosclerosis.

Effects of histidine and vitamin C on isoproterenol-induced acute myocardial infarction in rats

In the present study, we investigated the effects of histidine and vitamin C (alone or in combination) treatments against isoproterenol (a β-adrenergic receptor agonist)-induced acute myocardial infarction in rats. We used propranolol (a β-adrenergic receptor blocker) to compare the results. Rats were given intraperitoneal injections of histidine (40 mg kg(-1)) and vitamin C (40 mg kg(-1)) alone and combined daily for 21 days. Propranolol (10 mg kg(-1)) was orally administered daily for 10 days (from day 11 to day 21). Myocardial infarction was induced by subcutaneous injections of 150 mg kg(-1) of isoproterenol at an interval of 24 hr on days 20 and 21. Blood and tissue samples were taken for histopathological and biochemical evaluations following electrocardiography recording on day 21. Isoproterenol elevated ST segment, increased heart weight, heart rate, serum activities of aspartate transaminase, lactate dehydrogenase, creatine kinase-MB and heart tissue content of malondialdehyde, and decreased R wave amplitude and superoxide dismutase and catalase activities of heart tissue. Necrosis, edema and inflammatory cells infiltration were observed in myocardial tissue sections. Our results indicated that histidine and vitamin C alone, and especially in combination prevent isoproterenol-induced cardiotoxicity and have similar protective effects with propranolol. Cardioprotective effects of histidine and vitamin C may be associated with their ability to reduce free radical-induced toxic effects.

Acute myocardial infarction and subclavian artery occlusion in a 41-year-old woman with Behçet's disease: coronary and large vessel arteritis

We report the case of a 41-year-old Chinese woman with Behçet's disease (BD) complicated by acute myocardial infarction, requiring inotropic and ventilatory support. Angiography showed critical left anterior descending coronary artery stenosis, a blocked left subclavian artery and left carotid artery stenosis. The patient was successfully treated with a high dose of immunosuppressants, standard anti-ischaemic therapy and percutaneous coronary intervention. Although life-threatening, coronary arteritis is a treatable manifestation of BD. We suggest that the diagnosis of coronary arteritis be considered in patients with BD who present with chest pain. Involvement of other arteries should also be looked out for in these patients.

Systemic inflammatory response following acute myocardial infarction

Acute cardiomyocyte necrosis in the infarcted heart generates damage-associated molecular patterns, activating complement and toll-like receptor/interleukin-1 signaling, and triggering an intense inflammatory response. Inflammasomes also recognize danger signals and mediate sterile inflammatory response following acute myocardial infarction (AMI). Inflammatory response serves to repair the heart, but excessive inflammation leads to adverse left ventricular remodeling and heart failure. In addition to local inflammation, profound systemic inflammation response has been documented in patients with AMI, which includes elevation of circulating inflammatory cytokines, chemokines and cell adhesion molecules, and activation of peripheral leukocytes and platelets. The excessive inflammatory response could be caused by a deregulated immune system. AMI is also associated with bone marrow activation and spleen monocytopoiesis, which sustains a continuous supply of monocytes at the site of inflammation. Accumulating evidence has shown that systemic inflammation aggravates atherosclerosis and markers for systemic inflammation are predictors of adverse clinical outcomes (such as death, recurrent myocardial infarction, and heart failure) in patients with AMI.

Fetuin-A 742 (C/T) and 766 (C/G) polymorphic sites are associated with increased risk of myocardial infarction in older patients (≥ 40 years of age)

Inflammation and genetics have key roles in the pathogenesis of atherosclerosis, and the etiology of myocardial infarction (MI). Recent studies have indicated that lower serum levels of fetuin-A may accelerate the vascular mineralization process, which leads to pathophysiological conditions, such as coronary heart disease and chronic renal failure. The aim of the present study was to evaluate the association between specific fetuin-A polymorphisms (742 and 766) that are associated with circulating serum levels, and MI cases. The study consisted of 292 participants; 146 healthy control subjects and 146 patients with MI. The patient group was divided into two subgroups: 56 MI ≤ 40 years and 90 MI ≥ 40 years. The genotype distribution of fetuin 742 (C/T) and fetuin 766 (C/G) were determined by restriction enzyme digestion of polymerase chain reaction products. A significant difference was determined between the patients with MI and the control subjects with regards to fetuin-A 742 C/T gene polymorphism (P=0.028), regardless of age. Genotype distributions of fetuin-A 742 (C/G, P=0.004) and 766 (C/T, P=0.017) were statistically different in the older patients with MI (MI ≥ 40 years old), as compared with the healthy controls; however, there were no significant differences between the younger patients with MI and the controls, with regards to fetuin-A 742 C/T (P=0.519) and 766 C/G (P=0.653) gene polymorphisms. In addition, an association was observed between the presence of fetuin-A 742 T and 766 G alleles, and MI cases. The present study demonstrates that fetuin-A 742 (C/T) and 766 (C/G) genotypes may be risk factors for MI in patients older than 40 years of age.