Vana Kolovou

A randomized trial of genotype-guided dosing of acenocoumarol and phenprocoumon.

BACKGROUND Observational evidence suggests that the use of a genotype-guided dosing algorithm may increase the effectiveness and safety of acenocoumarol and phenprocoumon therapy. METHODS We conducted two single-blind, randomized trials comparing a genotype-guided dosing algorithm that included clinical variables and genotyping for CYP2C9 and VKORC1 with a dosing algorithm that included only clinical variables, for the initiation of acenocoumarol or phenprocoumon treatment in patients with atrial fibrillation or venous thromboembolism. The primary outcome was the percentage of time in the target range for the international normalized ratio (INR; target range, 2.0 to 3.0) in the 12-week period after the initiation of therapy. Owing to low enrollment, the two trials were combined for analysis. The primary outcome was assessed in patients who remained in the trial for at least 10 weeks. RESULTS A total of 548 patients were enrolled (273 patients in the genotype-guided group and 275 in the control group). The follow-up was at least 10 weeks for 239 patients in the genotype-guided group and 245 in the control group. The percentage of time in the therapeutic INR range was 61.6% for patients receiving genotype-guided dosing and 60.2% for those receiving clinically guided dosing (P=0.52). There were no significant differences between the two groups for several secondary outcomes. The percentage of time in the therapeutic range during the first 4 weeks after the initiation of treatment in the two groups was 52.8% and 47.5% (P=0.02), respectively. There were no significant differences with respect to the incidence of bleeding or thromboembolic events. CONCLUSIONS Genotype-guided dosing of acenocoumarol or phenprocoumon did not improve the percentage of time in the therapeutic INR range during the 12 weeks after the initiation of therapy. (Funded by the European Commission Seventh Framework Programme and others; EU-PACT ClinicalTrials.gov numbers, NCT01119261 and NCT01119274.).

The role of common variants of the cholesteryl ester transfer protein gene in left main coronary artery disease

BackgroundThe cholesteryl ester transfer protein (CETP) has a central role in the lipid metabolism and therefore may alter the susceptibility to atherosclerosis.MethodsThe DNA of 471 subjects [133 subjects with angiographically documented left main coronary artery disease (LMCAD), 241 subjects with more peripheral coronary artery disease (MPCAD) and 97 subjects self reported healthy (Controls)] was analyzed for the frequency of TaqIB and I405V polymorphisms in the gene coding CETP.ResultsThere is no significant difference in CETP allele frequency or genotype distribution among LMCAD and MPCAD patients although there is statistical difference between LMCAD and Controls (p = 0.001). Specifically, patients with LMCAD and B1B1 genotype of TaqIB polymorphism were more frequent present compared to Controls (33.8% vs 22.9%, respectively). The frequency of B2B2 genotype was 3 times lower in the LMCAD group compared to Controls (10.5% vs 30.2%, respectively). In the LMCAD group the frequency of B1 allele compared to Controls was higher (62% vs 46%, respectively, p = 0.001). The relationship between TaqIB gene polymorphism and the LMCAD was independent of lipid profile, with the exception of apolipoprotein A.ConclusionsThese findings indicate that the TaqIB polymorphism may have potential importance in screening individuals at high risk for developing CAD. However, this polymorphism cannot distinguish between LMCAD and MPCAD. Further prospective investigations in larger populations are required to confirm these findings.

Lipidomics in vascular health: current perspectives

Identifying the mechanisms that convert a healthy vascular wall to an atherosclerotic wall is of major importance since the consequences may lead to a shortened lifespan. Classical risk factors (age, smoking, obesity, diabetes mellitus, hypertension, and dyslipidemia) may result in the progression of atherosclerotic lesions by processes including inflammation and lipid accumulation. Thus, the evaluation of blood lipids and the full lipid complement produced by cells, organisms, or tissues (lipidomics) is an issue of importance. In this review, we shall describe the recent progress in vascular health research using lipidomic advances. We will begin with an overview of vascular wall biology and lipids, followed by a short analysis of lipidomics. Finally, we shall focus on the clinical implications of lipidomics and studies that have examined lipidomic approaches and vascular health.

Association of gender, ABCA1 gene polymorphisms and lipid profile in Greek young nurses

ObjectiveOne of the important proteins involved in lipid metabolism is the ATP-binding cassette transporter A1 (ABCA1) encoding by ABCA1 gene. In this study we evaluated the single nucleotide polymorphisms (SNPs) of ABCA1 gene. We analyzed SNPs in chromosome 9 such as rs2230806 (R219K) in the position 107620867, rs2230808 (R1587K) in the position 106602625 and rs4149313 (I883M) in the position 106626574 according to gender and lipid profile of Greek nurses.MethodsThe study population consisted of 447 (87 men) unrelated nurses who were genotyped for ABCA1 gene polymorphisms. Additionally, lipid profile [total cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol (LDL-C) and apolipoprotein A1] was evaluated.ResultsThe distribution of all three studied ABCA1 gene polymorphisms did not differ according to gender. However, only R219K genotype distribution bared borderline statistical significance (p = 0.08) between the two studied groups. Moreover, allele frequencies of R219K, R1587K and I88M polymorphisms did not differ according to gender. In general, blood lipid levels did not seem to vary according to ABCA1 gene polymorphisms, when testing all subjects or when testing only men or only women. However, a significant difference of LDL-C distribution was detected in all subjects according to R1587K genotype, indicating lower LDL-C levels with KK polymorphism (p = 0.0025). The above difference was solely detected on female population (p = 0.0053).ConclusionsThe ABCA1 gene polymorphisms frequency, distribution and lipid profile did not differ according to gender. However, in the female population the KK genotype of R1587K gene indicated lower LDL-C levels. Further studies, involving a higher number of individuals, are required to clarify genes and gender contribution.

ATP-binding cassette transporter A1 gene polymorphisms and serum lipid levels in young Greek nurses

ObjectiveThe ATP-binding cassette transporter A1 (ABCA1) is essential protein involved in lipid metabolism. The present study was undertaken to detect the possible association of polymorphisms in the ABCA1 gene [rs2230806 (R219K) and rs2230808 (R1587K)] and lipid profile in Greek young nurses.MethodsThe study population consisted of 308 unrelated nurses who were genotyped and the ABCA1 polymorphisms were detected. Additionally, lipid profile [total cholesterol (TC), triglycerides (TGs), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and apolipoprotein (apo) A] was evaluated.ResultsThere was no difference in the genotypic and allelic frequencies of the R219K polymorphism according to lipid profile. The R1587K genotypes differed significantly according to TC, LDL-C and TGs concentration (p = 0.023, p = 0.014 and p = 0.047, respectively). Particularly, significant difference in TC, LDL-C and TGs concentration was detected between RK and RR genotypes (p = 0.006, p = 0.004, p = 0.014, respectively). Women with RK genotype compared to RR genotype had higher concentration of TGs (134.25 mg/dl vs 108.89 mg/dl, p = 0.014, respectively), total cholesterol (207.41 mg/dl vs 187.69 mg/dl, p = 0.006, respectively), and LDL-C (110.6 mg/dl vs 96.9 mg/dl, p = 0.004, respectively).ConclusionsThese findings suggest that the R1587K polymorphism of ABCA1 gene was associated with lipid profile of Greek nurses. Women with RK genotype had higher TGs, total and LDL-C concentration compared to RR genotype. These observations may be significant in assessing the risk of CAD since a 1% change in LDL-C is associated with a 1% change of cardiovascular events. Also, TGs concentration were documented to play a significant role in women. However, this needs to be confirmed by larger studies.

Cholesteryl Ester Transfer Protein Gene Polymorphisms and Longevity Syndrome

Purpose: High levels of high density lipoprotein (HDL) cholesterol are associated with a decreased risk of coronary heart disease (CHD). Subjects with high levels of HDL cholesterol (>70 mg/dl; 1.79 mmol/l) as well as high levels of low density lipoprotein (LDL) cholesterol, could represent a group with longevity syndrome (LS). Since HDL particles are influenced by cholesteryl ester transfer protein (CETP) activity, it is worth studying the CETP polymorphism. The aim of the study was to detect whether 2 genetic variants of the CETP are associated with the LS. Subjects and Methods: The study population consisted of 136 unrelated men and women with no personal and family history of CHD; 69 met the criteria for LS and 67 did not meet these criteria and had “normal” HDL cholesterol (>40 and <70 mg/dl; >1.03 and <1.79 mmol/l). All patients were genotyped for the TaqIB and I405V polymorphisms. Results: The B2 allele frequency of TaqIB polymorphism was higher in the LS in comparison with the non-LS group (p=0.03) whereas B1 allele frequency was higher in the non-LS group (p=0.03). Conclusions: Gene polymorphisms could help decide whether individuals who have increased levels of both LDL cholesterol and HDL cholesterol require treatment. Some of the prerequisites could include that subjects with LS should not only have very high levels of HDL cholesterol but also favorable gene polymorphisms. However, further investigations with a larger sample and including other gene polymorphisms, are needed.

The Frequency of 4 Common Gene Polymorphisms in Nonagenarians, Centenarians, and Average Life Span Individuals

Single nucleotide polymorphisms of angiotensin-converting enzyme (ACE) such as rs1799752, nuclear factor kappa B (NFkB) such as rs28362491 and cholesteryl ester transport protein (CETP) such as rs708272 (TaqB1) and rs5882 (I405V) were evaluated in nonagenarians, centenarians, and average life span individuals (controls). The study population (n = 307; 190 nonagenarians, 12 centenarians and 105 middle-aged controls) was genotyped for ACE, NFkB, and CETP genetic variants. The age of nonagenarian and centenarian group ranged between 90 and 111 years; centenarians and controls age ranged from 99 to 111, and from 18 to 80 years, respectively. The I carriers of ACE I/D gene were fewer in nonagenarians compared to centenarians (37.6% vs 62.5%, P = .016). The I carriers of ACE gene were more frequent in centenarians compared to controls (62% vs 41%, P = .045). No differences in frequency of common NFkB and CETP genotypes between patients with exceptional longevity and middle-aged patients were observed.

No effect of CYP3A4 intron 6 C>T polymorphism (CYP3A4*22) on lipid-lowering response to statins in Greek patients with primary hypercholesterolemia

Abstract Background: Interindividual variability exists in statin lipid-lowering response, partially attributed to genetic factors. CYP3A4 intron 6 C>T polymorphism (CYP3A4*22 allele, rs35599367) has been recently identified and was associated with reduced CYP3A4 expression. We analyzed the association of CYP3A4*22 allele with response to atorvastatin and simvastatin. Methods: A total of 416 statin-treated (207 atorvastatin- and 209 simvastatin-treated) adults with primary hypercholesterolemia were included in the study. Total cholesterol and low-density lipoprotein cholesterol were measured at baseline and on 6 months of treatment. CYP3A4*22 allele was analyzed with TaqMan assay. Results: In the entire cohort population, 41 individuals carried CYP3A4*22 allele (18 in atorvastatin and 23 in simvastatin treatment). CYP3A4*22 allele was not associated with lipid-lowering response to atorvastatin or simvastatin. No sex-gene or statin dose-gene interaction was observed in either statin-treated patient cohort. Conclusions: The effect of CYP3A4*22 allele on lipid-lowering response to CYP3A metabolized statins, if present, can potentially be masked by relevant confounding or uncontrolled factors; therefore, further population-driven studies are required.

Impact of 3 Common ABCA1 Gene Polymorphisms on Optimal vs Non-Optimal Lipid Profile in Greek Young Nurses.

Objective: This study is in line with two previous ones from our group. They evaluated the influence of ATP-binding cassette transporter A1 (ABCA1) gene polymorphisms [such as rs2230806 (R219K), rs2230808 (R1587K) and rs4149313 (I883M)] on the human lipid profile (defined as Optimal and Non-Optimal). Methods: The present study included 447 unrelated young women and men self-reported as being healthy and that attended the University of Nursing of Technological and Educational Institution. All subjects were genotyped and the ABCA1 polymorphisms (R219K, R1587K and I883M) were recorded. According to lipid profile [total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol (LDL-C)] the subjects were separated into those with optimal lipid profile (Optimal Group, n=209) and Non-Optimal Group (n=238). Results: No statistical differences were observed in the distribution of R219K, R1587K and I883M polymorphisms according to the lipid profile (p>0.05 in all cases). No statistical differences were observed in the distribution of R219K, R1587K and I883M polymorphisms according to sex (p>0.05 in all cases). However, Logistic Regression revealed that subjects with RK (R1587K polymorphism) genotype had 69% increased risk on average of having LDL-C above normal limits as compared with those with RR genotype. Similarly, subjects with K allele (R1587K polymorphism) had 59% increased risk on average of having LDL-C above normal limits compared with those with R allele. Conclusion: These findings suggest that R1587K polymorphism of ABCA1 gene may influence the lipid profile. However, this needs to be confirmed by larger studies.

We Are Ageing

Ageing and longevity is unquestioningly complex. Several thoughts and mechanisms of ageing such as pathways involved in oxidative stress, lipid and glucose metabolism, inflammation, DNA damage and repair, growth hormone axis and insulin-like growth factor (GH/IGF), and environmental exposure have been proposed. Also, some theories of ageing were introduced. To date, the most promising leads for longevity are caloric restriction, particularly target of rapamycin (TOR), sirtuins, hexarelin and hormetic responses. This review is an attempt to analyze the mechanisms and theories of ageing and achieving longevity.