Danijel Petrovič

Interaction Between Gene Polymorphisms of Renin-angiotensin System and Metabolic Risk Factors in Premature Myocardial Infarction

The renin-angiotensin system is involved in the pathogenesis of coronary artery disease (CAD) and myocardial infarction (MI). The authors investigated the association of genetic variability in the renin-angiotensin system (RAS) with premature MI and interactive effects between gene polymorphisms and metabolic risk factors on MI risk. Their study compared 142 patients with MI younger than 55 years with 142 healthy subjects. Polymorphisms of angiotensin-I converting enzyme (ACE) gene (insertion/deletion), angiotensinogen gene (M235T), and angiotensin-II type-1 receptor (AGT 1R) gene (A1166C) were tested. The ACE-DD (deletion/deletion) genotype conferred a twofold independent risk for MI (confidence interval [CI] = 1.1-3.7; p=0.01) after adjustment for cardiovascular risk factors, whereas angiotensinogen-TT genotype and AGT1R- AA genotype were not independent risk factors for MI. An interactive effect on MI risk was found between ACE-DD and AGT1R-AA genotypes (odds ratio [OR] = 2, 95% CI = 1-3.9), between ACE-DD and angiotensinogen-TT genotypes (OR=2.7, 95% CI= 1-7.3), as well as among ACE-DD, angiotensinogen-TT, and AGT1R-AA genotypes (OR = 4.8, 95% CI = 1-22.8). Similarly, metabolic risk factors interacted with angiotensinogen-TT genotype (OR=2, 95% CI = 1.1-3.9) on MI risk. The ACE-DD genotype is an independent risk factor for MI in patients younger than 55 years. Additionally, the authors provide evidence of an interactive effect on MI risk between risk genotypes of RAS, as well as between the angiotensinogen-TT genotype and metabolic risk factors.

Familial progressive sinoatrial and atrioventricular conduction disease of adult onset with sudden death, dilated cardiomyopathy, and brachydactyly. A new type of heart-hand syndrome?

We identified a family with 10 affected members in four generations suffering from adult‐onset progressive sinoatrial and atrioventricular conduction disease, sudden death due to ventricular tachyarrhythmia, dilated cardiomyopathy, and a unique type of brachydactyly with mild hand involvement (short distal, middle, proximal phalanges and clinodactyly) and more severe foot involvement (short distal, proximal phalanges and metatarsal bones, short or absent middle phalanges, terminal symphalangism, duplication of the bases of the second metatarsals, extra ossicles, and syndactyly). The phenotype differences from other reported genetic abnormalities and linkage exclusion of Holt–Oram syndrome, ulnar–mammary syndrome, brachydactyly type B or Robinow syndrome, and cardiac conduction disease or Brugada syndrome loci suggest that we report on a new hereditary heart‐hand syndrome.

Carotid Intima Media-thickness and Genes Involved in Lipid Metabolism in Diabetic Patients using Statins – a Pathway Toward Personalized Medicine

The prognostic importance of large artery structure and function in relation to cardiovascular morbidity and mortality, together with the identification of new genetic risk factors have been two major areas of investigation in recent years. Carotid intima-media thickness (CIMT), as measured by B-mode ultrasound, is a surrogate marker for atherosclerosis and can be used to detect an accelerated disease process as well as subclinical disease. However, the genetic basis for CIMT variation is almost unknown. Cardiovascular genetics has led to numerous clinical studies generally focused on only one candidate gene and were frequently conducted in subjects with cardiovascular diseases and/or taking drugs that could affect CIMT. Pharmacogenetics is the study of the effect of a medication as it relates to single or defined sets of genes. An important goal of pharmacogenetics in cardiovascular disorders is to integrate the two (drugs plus genes) so that true personalized therapy can be delivered. In this paper, we will discuss the interaction between genes involved in lipid metabolism and statin therapy that affects intermediate phenotype (plasma lipid levels) and CIMT in patients with type 2 diabetes.

Is diabetic cardiomyopathy a specific entity

Diabetes mellitus (DM) is characterised by hyperglycemia, insulin resistance and metabolic dysregulation leading to diastolic and systolic dysfunction in diabetes. In this review, the pathogenetic and pathomorphological changes leading to diastolic and systolic dysfunction in diabetes are discussed. Changes in metabolic signalling pathways, mediators and effectors contribute to the pathogenesis of cardiac dysfunction in DM called diabetic cardiomyopathy (DC). Echocardiographic studies report on the association between DM and the presence of cardiac hypertrophy and myocardial stiffness that lead to diastolic dysfunction. More recently reported echocardiographic studies with more sensitive techniques, such as strain analysis, also observed systolic dysfunction as an early marker of DC. Depression of systolic and diastolic function is continuum and the line of separation is artificial. To conclude, according to current knowledge, DC is expected to be a common single phenotype that is caused by different pathogenetic and pathomorphological changes leading to diastolic and systolic dysfunction in diabetes.

Polymorphisms in the Promoter Region of the Basic Fibroblast Growth Factor Gene Are Not Associated with Myocardial Infarction in a Slovene Population with Type 2 Diabetes

Basic fibroblast growth factor (bFGF) is a multifunctional growth factor that may play a significant role in atherosclerotic vascular complications in patients with type 2 diabetes. This study was designed to investigate the association between genetic polymorphisms (–553 T/A, −834 T/A and −921 C/G) in the promoter region of the bFGF gene and myocardial infarction (MI) in 443 patients with type 2 diabetes (149 with MI and 294 with no history of coronary artery disease). The −553 T/A, −834 T/A and −921 C/G polymorphisms of the bFGF gene were found not to be risk factors for MI in patients with type 2 diabetes. The impact of bFGF gene polymorphisms on serum bFGF levels was also investigated and significantly higher serum levels of bFGF were demonstrated in diabetes patients with the TA genotype of the −553 T/A polymorphism compared with diabetes patients with the TT wild type genotype (9.0 ± 5.6 ng/l versus 3.0 ± 1.9 ng/l, respectively). Thus, the tested bFGF gene polymorphisms cannot be used as genetic markers for MI in diabetic Caucasians.

The PECAM-1 gene polymorphism — a genetic marker of myocardial infarction

We investigated a possible association between the C373G (Leu125Val) polymorphism in the platelet endothelial cell adhesion molecule-1 (PECAM-1) and myocardial infarction (MI) among patients with type 2 diabetes (T2DM) in the Slovene population (Caucasians). The study population of this cross-sectional analysis consisted of 452 subjects with T2DM lasting more than 10 years: 142 patients with MI (MI group) and 310 patients (control group) with no history of coronary diseases. There were significant differences of PECAM-1 genotype distribution in patients with MI (CC=28.2%, CG=47.2% and GG=24.6%) compared with subjects in the control group (CC=17.1%, CG=53.5% and GG=29.4%). The multivariate model showed that the CC genotype of the PECAM-1 gene polymorphism (C373G) (OR=1.9, 95% CI 1.2–3.0, P=0.007) was an independent risk factor for MI. The C allele frequency was also significantly higher (P=0.005) in MI (51.8%) than in control subjects (41%). In addition, our study revealed the connection between smoking habits, the duration of diabetes and the total and LDL cholesterol serum levels and MI in Slovene T2DM patients. We suggest that the tested polymorphism of PECAM-1 (C373G) is associated with MI. Therefore, it might be used as genetic marker of MI in T2DM.

The optimal combination of cartilage source and apparatus for long-term in vitro chondrocyte viability analysis.

Abstract:  Most studies of long‐term chondrocytes survival were for tissue banks. They showed a gradual reduction in the viable chondrocytes percentage as a function of time and ambient temperature, but the samples were harvested under optimal conditions. The aim of our study was to determine the most reliable combination of cartilage source and assay for the in vitro postmortem chondrocyte viability analysis in the conditions that imitate a dead body. Osteochondral cylinders were procured from femoral condyles and talar trochleas of three male donors and stored in the cell culture media at 4 ± 2°C and 23 ± 2°C. The samples were analyzed by a cell viability analyzer and a confocal laser scanning microscope (CLSM) initially 24–36 h after death and then in 4‐week intervals. The results reconfirmed the significant influence of time (p = 0.0002), but not of the temperature (p = 0.237). The largest reproducibility was presented for the knee joint and the CLSM.

Diabetic nephropathy in type 2 diabetes: MPO T-764C genotype is associated with oxidative stress

BackgroundOxidative stress is a single mechanism relating all major pathways responsible for diabetic damage and plays an important role in diabetes development, progression and related vascular complications. To investigate the impact of oxidative stress related gene polymorphisms on development of diabetic nephropathy (DN), we tested 7 polymorphic variants that could hypothetically affect the ability of the antioxidant defense system and thus accelerate oxidative stress.Methodology197 Slovenian (Caucasian) type 2 diabetic (T2D) patients, age 34–83, classified into two groups according to the presence of DN, were tested for SOD2 Val16Ala (rs4880), p22 phox C242T (rs4673), CAT C-262T (rs1001179), MPO T-764C (rs2243828), GSTP1 Ile105Val (rs1695), GSTT1 and GSTM1 deletion polymorphisms using PCR, RFLP and qPCR. Oxidative stress was assessed through serum 8-hydroxy-2-deoxyguanosine (8-OHdG) level. Results were analyzed using ANOVA, Chi-square test and multivariate logistic regression.Results and ConclusionsDespite the commonly recognized link between oxidative stress and diabetes and its complications we found no association between the selected polymorphisms and DN. However, we confirmed an association between oxidative stress level and MPO T-764C genotype, which was tested in relation to DN for the first time.

No association between NOS2 and NOS3 polymorphisms and diabetic nephropathy in type 2 diabetics

BackgroundDiabetic animal models suggest the involvement of nitric oxide (NO)-producing enzymes in the development of diabetic nephropathy (DN). While early stages of DN are associated with increased intrarenal NO, advanced DN is related to progressive NO deficiency. NO collaborates in reactive nitrogen compounds production, contributing to accelerated oxidative stress. To investigate the impact of genetic polymorphisms of NO-producing enzymes on DN development, we tested 3 polymorphic variants that could affect their function and compared genotype status to an oxidative stress marker.Methodology198 Slovenian (Caucasian) type 2 diabetic (T2D) patients, age 34–83, were classified into two groups according to the presence of DN and tested for eNOS Glu298Asp, eNOS 4a/b and iNOS Ser608Leu polymorphisms using PCR and qPCR. Oxidative stress was assessed through serum 8-OHdG level. Results were analyzed using ANOVA, Chi-square test and multivariate logistic regression.ResultsWe found no association between the selected polymorphisms and DN. However, we found a significant increase in oxidative stress level in iNOS 608Leu/Leu patients.ConclusionsWe failed to demonstrate the association between the selected eNOS and iNOS genetic polymorphisms and DN. Our results reflect the multifactorial nature of DN in addition to genetic heterogeneity within and between the populations.

Association of the −262C/T polymorphism in the catalase gene promoter with carotid atherosclerosis in Slovenian patients with type 2 diabetes

Genetic variations of the antioxidant enzymes may influence the susceptibility to oxidative stress and consequently the development and progression of diabetic complications. The aim of the current study was to test the association between the −262C/T polymorphism in the catalase gene promoter and carotid atherosclerosis in Slovenian patients with type 2 diabetes. Two-hundred and eighty six diabetics and 150 healthy controls were enrolled in the study. Carotid atherosclerosis was quantified ultrasonographiocally by carotid intima-media thickness (CITM), plaque score and plaque type. Genotypes were determined using the real-time PCR. Fibrinogen concentration showed a borderline statistically significant difference due to catalase genotypes (p=0,05). No difference in clinical characteristics, CIMT, plaque stability or plaque score was observed. Logistic regression model adjusted for age, gender, smoking, BMI, lipid parameters and duration of hypertension and diabetes showed significant association of T allele and lower risk for higher plaque score (OR=0,25; p=0,025). No association with CIMT>1mm and unstable plaques was observed. T allele of −262C/T is associated with lower risk for higher plaque score but it did not affect clinical parameters, CIMT and plaque stability. Whether this polymorphism can be used as a genetic marker for advanced carotid atherosclerosis in diabetic patients needs to be evaluated in the future.