Ticagrelor versus prasugrel in diabetic patients with an acute coronary syndrome. A pharmacodynamic randomised study

Optimal P2Y12 receptor blockade is critical to prevent ischaemic recurrence in patients undergoing percutaneous coronary intervention (PCI). We aimed to compare the level of platelet reactivity (PR) inhibition achieved by prasugrel and ticagrelor loading dose (LD) in diabetic acute coronary syndrome (ACS) patients undergoing PCI. We performed a single-center prospective open-label randomised trial. Patients with diabetes mellitus undergoing PCI for an ACS were randomised to receive prasugrel 60 mg or ticagrelor 180 mg. The primary endpoint of the study was the level of platelet reactivity (PR) assessed between 6 and 18 hours post-LD using the VASP index. We randomised 100 diabetic patients undergoing PCI for an ACS. No difference was observed in baseline characteristics between the two groups. In particular, the rate of patient receiving insulin therapy was identical (25 vs 28.6%; p =0.7). Ticagrelor achieved a significantly lower PR compared to prasugrel loading dose (17.3 ± 14.2 vs 27.7 ± 23.3%; p=0.009). In addition the rate of high on-treatment platelet reactivity, defined by a VASP ≥50%, tend to be lower in the ticagrelor group although the difference did not reach statistical significance (6 vs 16%; p=0.2). The rate of low on treatment PR was identical (60 vs 54%; p=0.8). The present study demonstrates that ticagrelor LD is superior to prasugrel LD to reduce PR in ACS patients with diabetes mellitus. Whether the higher potency of ticagrelor could translate into a clinical benefit should be investigated.

Assessing post-treatment platelet reactivity: a focus on patient selection and setting

Dual antiplatelet therapy is critical to inhibit platelet reactivity in order to prevent ischemic recurrences in stented patients. However, studies have observed a variable blockade of the P2Y12 adenosine diphosphate receptor between patients following clopidogrel intake. This interindividual variability in the biological response is not uncommon with clopidogrel (about 50%) and even prasugrel (20%). High on-treatment platelet reactivity (HTPR) is correlated with thrombotic events following percutaneous coronary intervention. Several studies suggested that tailoring of antiplatelet therapy based on platelet reactivity (PR) monitoring could safely reduce the rate of major adverse cardiovascular events in HTPR patients. In addition, low on-treatment PR was recently associated with bleeding events both in patients treated with prasugrel and clopidogrel. Of importance, bleedings are associated with a poor prognosis in stented patients. Overall, the potential of PR monitoring to individualize antiplatelet therapy might benefit stented patients by reducing both ischemic and bleeding risks. However, such strategies remain to be evaluated in adequately designed large-scale randomized clinical trials.

Gene-nutrient interactions on the phosphoenolpyruvate carboxykinase influence insulin sensitivity in metabolic syndrome subjects

BACKGROUND & AIMS

Genetic background may interact with habitual dietary fat composition, and affect development of the metabolic syndrome (MetS). The phosphoenolpyruvate carboxykinase gene (PCK1) plays a significant role regulating glucose metabolism, and fatty acids are key metabolic regulators, which interact with transcription factors and influence glucose metabolism. We explored genetic variability at the PCK1 gene locus in relation to degree of insulin resistance and plasma fatty acid levels in MetS subjects. Moreover, we analyzed the PCK1 gene expression in the adipose tissue of a subgroup of MetS subjects according to the PCK1 genetic variants.

METHODS

Insulin sensitivity, insulin secretion, glucose effectiveness, plasma concentrations of C-peptide, fatty acid composition and three PCK1 tag-single nucleotide polymorphisms (SNPs) were determined in 443 MetS participants in the LIPGENE cohort.

RESULTS

The rs2179706 SNP interacted with plasma concentration of n - 3 polyunsaturated fatty acids (n - 3 PUFA), which were significantly associated with plasma concentrations of fasting insulin, peptide C, and HOMA-IR. Among subjects with n - 3 PUFA levels above the population median, carriers of the C/C genotype exhibited lower plasma concentrations of fasting insulin (P = 0.036) and HOMA-IR (P = 0.019) as compared with C/C carriers with n - 3 PUFA below the median. Moreover, homozygous C/C subjects with n - 3 PUFA levels above the median showed lower plasma concentrations of peptide C as compared to individuals with the T-allele (P = 0.006). Subjects carrying the T-allele showed a lower gene PCK1 expression as compared with carriers of the C/C genotype (P = 0.015).

CONCLUSIONS

The PCK1 rs2179706 polymorphism interacts with plasma concentration of n - 3 PUFA levels modulating insulin resistance in MetS subjects.

A Period 2 genetic variant interacts with plasma SFA to modify plasma lipid concentrations in adults with metabolic syndrome

Genetic variants of Period 2 (PER2), a circadian clock gene, have been linked to metabolic syndrome (MetS). However, it is still unknown whether these genetic variants interact with the various types of plasma fatty acids. This study investigated whether common single nucleotide polymorphisms (SNPs) in the PER2 locus (rs934945 and rs2304672) interact with various classes of plasma fatty acids to modulate plasma lipid metabolism in 381 participants with MetS in the European LIPGENE study. Interestingly, the rs2304672 SNP interacted with plasma total SFA concentrations to affect fasting plasma TG, TG-rich lipoprotein (TRL-TG), total cholesterol, apoC-II, apoB, and apoB-48 concentrations (P-interaction < 0.001-0.046). Carriers of the minor allele (GC+GG) with the highest SFA concentration (>median) had a higher plasma TG concentration (P = 0.001) and higher TRL-TG (P < 0.001) than the CC genotype. In addition, participants carrying the minor G allele for rs2304672 SNP and with a higher SFA concentration (>median) had higher plasma concentrations of apo C-II (P < 0.001), apo C-III (P = 0.009), and apoB-48 (P = 0.028) compared with the homozygotes for the major allele (CC). In summary, the rs2304672 polymorphism in the PER2 gene locus may influence lipid metabolism by interacting with the plasma total SFA concentration in participants with MetS. The understanding of these gene-nutrient interactions could help to provide a better knowledge of the pathogenesis in MetS.

Insulin receptor substrate-2 gene variants in subjects with metabolic syndrome: association with plasma monounsaturated and n-3 polyunsaturated fatty acid levels and insulin resistance

SCOPE

Several insulin receptor substrate-2 (IRS-2) polymorphisms have been studied in relation to insulin resistance and type 2 diabetes. To examine whether the genetic variability at the IRS-2 gene locus was associated with the degree of insulin resistance and plasma fatty acid levels in metabolic syndrome (MetS) subjects.

METHODS AND RESULTS

Insulin sensitivity, insulin secretion, glucose effectiveness, plasma fatty acid composition and three IRS-2 tag-single nucleotide polymorphisms (SNPs) were determined in 452 MetS subjects. Among subjects with the lowest level of monounsaturated (MUFA) (below the median), the rs2289046 A/A genotype was associated with lower glucose effectiveness (p<0.038), higher fasting insulin concentrations (p<0.028) and higher HOMA IR (p<0.038) as compared to subjects carrying the minor G-allele (A/G and G/G). In contrast, among subjects with the highest level of MUFA (above the median), the A/A genotype was associated with lower fasting insulin concentrations and HOMA-IR, whereas individuals carrying the G allele and with the highest level of ω-3 polyunsaturated fatty acids (above the median) showed lower fasting insulin (p<0.01) and HOMA-IR (p<0.02) as compared with A/A subjects.

CONCLUSION

The rs2289046 polymorphism at the IRS2 gene locus may influence insulin sensitivity by interacting with certain plasma fatty acids in MetS subjects.

Increased levels of microparticles originating from endothelial cells, platelets and erythrocytes in subjects with metabolic syndrome: relationship with oxidative stress

BACKGROUND AND AIMS

The Metabolic Syndrome (MetS) is associated with increased cardiovascular risk. Circulating microparticles (MP) are involved in the pathogenesis of atherothrombotic disorders and are raised in individual with CVD. We measured their level and cellular origin in subjects with MetS and analyzed their associations with 1/anthropometric and biological parameters of MetS, 2/inflammation and oxidative stress markers.

METHODS AND RESULTS

Eighty-eight subjects with the MetS according to the NCEP-ATPIII definition were enrolled in a bicentric study and compared to 27 healthy controls. AnnexinV-positive MP (TMP), MP derived from platelets (PMP), erythrocytes (ErMP), endothelial cells (EMP), leukocytes (LMP) and granulocytes (PNMP) were determined by flow cytometry. MetS subjects had significantly higher counts/μl of TMP (730.6±49.7 vs 352.8±35.6), PMP (416.0±43.8 vs 250.5±23.5), ErMP (243.8±22.1 vs 73.6±19.6) and EMP (7.8±0.8 vs 4.0±1.0) compared with controls. LMP and PNMP were not statistically different between groups. Multivariate analysis demonstrated that each criterion for the MetS influenced the number of TMP. Waist girth was a significant determinant of PMP and EMP level and blood pressure was correlated with EMP level. Glycemia positively correlated with PMP level whereas dyslipidemia influenced EMP and ErMP levels. Interestingly, the oxidative stress markers, plasma glutathione peroxydase and urinary 8-iso-prostaglandin F(2) α, independently influenced TMP and PMP levels whereas inflammatory markers did not, irrespective of MP type.

CONCLUSION

Increased levels of TMP, PMP, ErMP and EMP are associated with individual metabolic abnormalities of MetS and oxidative stress. Whether MP assessment may represent a marker for risk stratification or a target for pharmacological intervention deserves further investigation.

Glucokinase regulatory protein genetic variant interacts with omega-3 PUFA to influence insulin resistance and inflammation in metabolic syndrome

Glucokinase Regulatory Protein (GCKR) plays a central role regulating both hepatic triglyceride and glucose metabolism. Fatty acids are key metabolic regulators, which interact with genetic factors and influence glucose metabolism and other metabolic traits. Omega-3 polyunsaturated fatty acids (n-3 PUFA) have been of considerable interest, due to their potential to reduce metabolic syndrome (MetS) risk.

Objective

To examine whether genetic variability at the GCKR gene locus was associated with the degree of insulin resistance, plasma concentrations of C-reactive protein (CRP) and n-3 PUFA in MetS subjects.

Design

Homeostasis model assessment of insulin resistance (HOMA-IR), HOMA-B, plasma concentrations of C-peptide, CRP, fatty acid composition and the GCKR rs1260326-P446L polymorphism, were determined in a cross-sectional analysis of 379 subjects with MetS participating in the LIPGENE dietary cohort.

Results

Among subjects with n-3 PUFA levels below the population median, carriers of the common C/C genotype had higher plasma concentrations of fasting insulin (P = 0.019), C-peptide (P = 0.004), HOMA-IR (P = 0.008) and CRP (P = 0.032) as compared with subjects carrying the minor T-allele (Leu446). In contrast, homozygous C/C carriers with n-3 PUFA levels above the median showed lower plasma concentrations of fasting insulin, peptide C, HOMA-IR and CRP, as compared with individuals with the T-allele.

Conclusions

We have demonstrated a significant interaction between the GCKR rs1260326-P446L polymorphism and plasma n-3 PUFA levels modulating insulin resistance and inflammatory markers in MetS subjects. Further studies are needed to confirm this gene-diet interaction in the general population and whether targeted dietary recommendations can prevent MetS in genetically susceptible individuals.

Trial Registration

ClinicalTrials.gov NCT00429195

Calpain-10 interacts with plasma saturated fatty acid concentrations to influence insulin resistance in individuals with the metabolic syndrome

BACKGROUND

Calpain-10 protein (intracellular Ca(2+)-dependent cysteine protease) may play a role in glucose metabolism, pancreatic β cell function, and regulation of thermogenesis. Several CAPN10 polymorphic sites have been studied for their potential use as risk markers for type 2 diabetes and the metabolic syndrome (MetS). Fatty acids are key metabolic regulators that may interact with genetic factors and influence glucose metabolism.

OBJECTIVE

The objective was to examine whether the genetic variability at the CAPN10 gene locus is associated with the degree of insulin resistance and plasma fatty acid concentrations in subjects with MetS.

DESIGN

The insulin sensitivity index, glucose effectiveness, insulin resistance [homeostasis model assessment of insulin resistance (HOMA-IR)], insulin secretion (disposition index, acute insulin response, and HOMA of β cell function), plasma fatty acid composition, and 5 CAPN10 single nucleotide polymorphisms (SNPs) were determined in a cross-sectional analysis of 452 subjects with MetS participating in the LIPGENE dietary intervention cohort.

RESULTS

The rs2953171 SNP interacted with plasma total saturated fatty acid (SFA) concentrations, which were significantly associated with insulin sensitivity (P < 0.031 for fasting insulin, P < 0.028 for HOMA-IR, and P < 0.012 for glucose effectiveness). The G/G genotype was associated with lower fasting insulin concentrations, lower HOMA-IR, and higher glucose effectiveness in subjects with low SFA concentrations (below the median) than in subjects with the minor A allele (G/A and A/A). In contrast, subjects with the G/G allele with the highest SFA concentrations (above the median) had higher fasting insulin and HOMA-IR values and lower glucose effectiveness than did subjects with the A allele.

CONCLUSION

The rs2953171 polymorphism at the CAPN10 gene locus may influence insulin sensitivity by interacting with the plasma fatty acid composition in subjects with MetS. This trial was registered at clinicaltrials.gov as NCT00429195.

Pleiotropic effects of TCF7L2 gene variants and its modulation in the metabolic syndrome: from the LIPGENE study

AIMS/HYPOTHESIS

Variants of the TCF7L2 gene predict the development of type 2 diabetes mellitus (T2DM). We investigated the associations between gene variants of TCF7L2 and clinical features of the metabolic syndrome (MetS) (an entity often preceding T2DM), and their interaction with non-genetic factors, including plasma saturated fatty acids (SFA) concentration and insulin resistance (IR).

METHODS

Fasting lipid profiles, insulin sensitivity, insulin secretion, anthropometrics, blood pressure and 10 gene variations of the TCF7L2 gene were determined in 450 subjects with MetS.

RESULTS

Several single nucleotide polymorphisms (SNP) showed phenotypic associations independent of SFA or IR. Carriers of the rare T allele of rs7903146, and of three other SNPs in linkage disequilibrium with rs7903146, had lower blood pressure and insulin secretion. High IR and the presence of the T-allele of rs7903146 acted synergistically to define those with reduced insulin secretion. Carriers of the minor allele of rs290481 exhibited an altered lipid profile, with increased plasma levels of apolipoprotein B, non-esterified fatty acids, cholesterol and apolipoprotein B in triglyceride rich lipoproteins, and LDL cholesterol. Carriers of the minor allele of rs11196224 that had higher plasma SFA levels showed elevated procoagulant/proinflammatory biomarkers, impaired insulin secretion and increased IR, whereas carriers of the minor allele of rs17685538 with high plasma SFA levels exhibited higher blood pressure.

CONCLUSIONS/INTERPRETATION

SNP in the TCF7L2 gene are associated with differences in insulin secretion, blood pressure, blood lipids and coagulation in MetS patients, and may be modulated by SFA in plasma or IR.

NOS3 gene polymorphisms are associated with risk markers of cardiovascular disease, and interact with omega-3 polyunsaturated fatty acids

OBJECTIVE

Omega-3 polyunsaturated fatty acids (n-3 PUFA) may protect against the development of cardiovascular disease (CVD). Genotype at key genes such as nitric oxide synthase (NOS3) may determine responsiveness to fatty acids. Gene-nutrient interactions may be important in modulating the development of CVD, particularly in high-risk individuals with the metabolic syndrome (MetS).

METHODS

Biomarkers of CVD risk, plasma fatty acid composition, and NOS3 single nucleotide polymorphism (SNP) genotype (rs11771443, rs1800783, rs1800779, rs1799983, rs3918227, and rs743507) were determined in 450 individuals with the MetS from the LIPGENE dietary intervention cohort. The effect of dietary fat modification for 12 weeks on metabolic indices of the MetS was determined to understand potential NOS3 gene-nutrient interactions.

RESULTS

Several markers of inflammation and dyslipidaemia were significantly different between the genotype groups. A significant gene-nutrient interaction was observed between the NOS3 rs1799983 SNP and plasma n-3 PUFA status on plasma triacylglycerol (TAG) concentrations. Minor allele carriers (AC+AA) showed an inverse association with significantly higher plasma TAG concentrations in those with low plasma n-3 PUFA status and vice versa but the major allele homozygotes (CC) did not. Following n-3 PUFA supplementation, plasma TAG concentrations of minor allele carriers of rs1799983 were considerably more responsive to changes in plasma n-3 PUFA, than major allele homozygotes.

CONCLUSIONS

Carriers of the minor allele at rs1799983 in NOS3 have plasma TAG concentrations which are more responsive to n-3 PUFA. This suggests that these individuals might show greater beneficial effects of n-3 PUFA consumption to reduce plasma TAG concentrations.

Gene-nutrient interactions in the metabolic syndrome: single nucleotide polymorphisms in ADIPOQ and ADIPOR1 interact with plasma saturated fatty acids to modulate insulin resistance

BACKGROUND

Progression of the metabolic syndrome (MetS) is determined by genetic and environmental factors. Gene-environment interactions may be important in modulating the susceptibility to the development of MetS traits.

OBJECTIVE

Gene-nutrient interactions were examined in MetS subjects to determine interactions between single nucleotide polymorphisms (SNPs) in the adiponectin gene (ADIPOQ) and its receptors (ADIPOR1 and ADIPOR2) and plasma fatty acid composition and their effects on MetS characteristics.

DESIGN

Plasma fatty acid composition, insulin sensitivity, plasma adiponectin and lipid concentrations, and ADIPOQ, ADIPOR1, and ADIPOR2 SNP genotypes were determined in a cross-sectional analysis of 451 subjects with the MetS who participated in the LIPGENE (Diet, Genomics, and the Metabolic Syndrome: an Integrated Nutrition, Agro-food, Social, and Economic Analysis) dietary intervention study and were repeated in 1754 subjects from the LIPGENE-SU.VI.MAX (SUpplementation en VItamines et Minéraux AntioXydants) case-control study (http://www.ucd.ie/lipgene).

RESULTS

Single SNP effects were detected in the cohort. Triacylglycerols, nonesterified fatty acids, and waist circumference were significantly different between genotypes for 2 SNPs (rs266729 in ADIPOQ and rs10920533 in ADIPOR1). Minor allele homozygotes for both of these SNPs were identified as having degrees of insulin resistance, as measured by the homeostasis model assessment of insulin resistance, that were highly responsive to differences in plasma saturated fatty acids (SFAs). The SFA-dependent association between ADIPOR1 rs10920533 and insulin resistance was replicated in cases with MetS from a separate independent study, which was an association not present in controls.

CONCLUSIONS

A reduction in plasma SFAs could be expected to lower insulin resistance in MetS subjects who are minor allele carriers of rs266729 in ADIPOQ and rs10920533 in ADIPOR1. Personalized dietary advice to decrease SFA consumption in these individuals may be recommended as a possible therapeutic measure to improve insulin sensitivity. This trial was registered at clinicaltrials.gov as NCT00429195.

I-FABP expression alters the intracellular distribution of the BODIPY C16 fatty acid analog

To investigate the structure-function relationships of intestinal fatty acid-binding protein (I-FABP) in cellular fatty acid (FA) trafficking, we compared the distribution of a fluorescent FA analog (BODIPY FL C16) in Cos-1 cells transiently transfected with the wild type protein (wt I-FABP) to that of a variant deleted of the alpha helical domain (HL I-FABP). In vector-only cells, BODIPY fluorescence was distributed throughout the cytoplasm. In the absence of added FA, wt I-FABP was found largely in the perinuclear region with some cytoplasmic staining as well. Addition of BODIPY FL C16 to transfected cells showed that the fluorescent FA was essentially completely colocalized with the protein in the cytoplasmic and perinuclear regions as well as in cytoplasmic clusters that are not observed in the absence of wt I-FABP. For HL I-FABP, the distribution of the protein in the absence of FA was diffusely cytoplasmic, in marked contrast to the wt protein. Addition of BODIPY led to less extensive colocalization than that observed for wt I-FABP. In particular, no localization to the perinuclear region was found. Organelle colocalization studies showed that both proteins colocalized with mitochondria and endoplasmic reticulum/golgi markers, but little with a lysosomal marker. The perinuclear localization for wt I-FABP and BODIPY did not show colocalization with any of the markers tested. Taken together, these results indicate that I-FABP binds FA in vivo and that the helical domain may be important for targeting I-FABP to a perinuclear domain but not, perhaps, to the endoplasmic reticulum, golgi apparatus or mitochondria.

The Medi-RIVAGE study: reduction of cardiovascular disease risk factors after a 3-mo intervention with a Mediterranean-type diet or a low-fat diet

BACKGROUND

Epidemiologic studies link Mediterranean-type diets to a low incidence of cardiovascular disease; however, few dietary intervention studies have been undertaken, especially in primary prevention.

OBJECTIVES

In the Mediterranean Diet, Cardiovascular Risks and Gene Polymorphisms (Medi-RIVAGE) study, the effects of a Mediterranean-type diet (Med group) or a low-fat diet (low-fat group) on risk factors were evaluated in 212 volunteers (men and women) with moderate risk factors for cardiovascular disease.

DESIGN

After the 3-mo dietary intervention, changes in many risk factors were evaluated. Dietary questionnaires and plasma nutritional markers were used to test compliance.

RESULTS

Although the dietary goals were only partially reached, changes in dietary habits were observed in both groups (n = 169): protein, carbohydrate, and fiber intakes increased and fat quality (decreased saturated fat and increased monounsaturated or polyunsaturated fat) improved. BMI, total and triacylglycerol-rich lipoprotein (TRL) cholesterol, triacylglycerols, TRL triacylglycerols, apolipoproteins A-I and B, insulinemia, glycemia, and the homeostasis model assessment score were significantly lower after 3 mo. The reductions in total cholesterol, triacylglycerols, and insulinemia remained significant after adjustment for BMI. There was a trend for a diet-by-time interaction for LDL cholesterol (P = 0.09). Our data predicted a 9% reduction in cardiovascular disease risk with the low-fat diet and a 15% reduction with this particular Mediterranean diet.

CONCLUSION

After a 3-mo intervention, both diets significantly reduced cardiovascular disease risk factors to an overall comparable extent.