Effect of ID ACE gene polymorphism on dietary composition and obesity-related anthropometric parameters in the Czech adult population

Genome-Wide Association Study of Maternal Genetic Effects on Intramuscular Fat and Fatty Acid Composition in Rabbits

Maternal genetic effects (MGE) could affect meat quality traits such as intramuscular fat (IMF) and its fatty acid composition. However, it has been scarcely studied, especially in rabbits. The objectives of the present study were, first, to assess the importance of MGE on intramuscular fat and fatty acid composition by applying a Bayesian maternal animal model in two rabbit lines divergently selected for IMF. The second objective was to identify genomic regions and candidate genes of MGE that are associated with the traits of these offspring, using Bayesian methods in a Genome Wide Association Study (GWAS). Quantitative analyses were performed using data from 1982 rabbits, and 349 animals from the 9th generation and 76 dams of the 8th generation with 88,512 SNPs were used for the GWAS. The studied traits were IMF, saturated fatty acids (total SFA, C14:0; myristic acid, C16:0; palmitic acid and C18:0; stearic acid), monounsaturated fatty acids (total MUFA, C16:1n-7; palmitoleic acid and C18:1n-9; oleic acid), polyunsaturated fatty acids (total PUFA, C18:2n-6; linoleic acid, C18:3n-3; α-linolenic acid and C20:4n-6; arachidonic acid), MUFA/SFA and PUFA/SFA. The proportion of phenotypic variance explained by the maternal genetic effect ranged from 8 to 22% for IMF, depending on the model. For fatty acid composition, the proportion of phenotypic variance explained by maternal genetic effects varied from 10% (C18:0) to 46% (MUFA) in a model including both direct and additive maternal genetic effects, together with the common litter effect as a random variable. In particular, there were significant direct maternal genetic correlations for C16:0, C18:1n9, C18:2n6, SFA, MUFA, and PUFA with values ranging from -0.53 to -0.89. Relevant associated genomic regions were located on the rabbit chromosomes (OCU) OCU1, OCU5 and OCU19 containing some relevant candidates (TANC2, ACE, MAP3K3, TEX2, PRKCA, SH3GL2, CNTLN, RPGRIP1L and FTO) related to lipid metabolism, binding, and obesity. These regions explained about 1.2 to 13.9% of the total genomic variance of the traits studied. Our results showed an important maternal genetic effect on IMF and its fatty acid composition in rabbits and identified promising candidate genes associated with these traits.

Dual Effect of the GHRL Gene Variant in the Molecular Pathogenesis of Obesity

Obesity is as a global health problem due to its interaction with complex chronic disorders such as cardiovascular disorders, type 2 diabetes mellitus (T2DM) and cancer. Despite the fact that pathogenesis of obesity is not yet clearly understood, it is associated with a combination of psychological, environmental and various genetic factors. Here, employing a case-control design, we aimed to examine the effects of the GHRL c.152C>T (p.Arg51Gln) (rs34911341) and c.214G>T (p.Leu72Met) (rs696217) markers on susceptibility to obesity in a Turkish-Cypriot population, as well as to evaluate whether these markers affect biochemical parameters and show their putative functional consequences. This study involved 211 Turkish-Cypriot subjects (106 obese and 95 non obese). Genotyping for the GHRL gene polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Our results indicate that the GHRL Leu72Met polymorphism was found to be significantly higher in obese patients, with respect to genotypic (p = 0.0012) and allelic (p = 0.0005) frequencies. Strikingly, the rs696217 GT genotype (heterozygous) had significantly lower serum high-density lipoprotein cholesterol (HDL-C) (p = 0.015) than GG (wild type) genotypes. Overall, Leu72Met susceptibility variant may be considered as risk and crucial marker for both obesity and cholesterol metabolism in the community of Turkish-Cypriots. Thus, the dual effect of the GHRL gene Leu72Met variant may be used for clinical diagnosis.

A comparison of a ketogenic diet with a LowGI/nutrigenetic diet over 6 months for weight loss and 18-month follow-up

BACKGROUND

Obesity and its related metabolic disturbances represent a huge health burden on society. Many different weight loss interventions have been trialled with mixed efficacy, as demonstrated by the large number of individuals who regain weight upon completion of such interventions. There is evidence that the provision of genetic information may enhance long-term weight loss, either by increasing dietary adherence or through underlying biological mechanisms.

METHODS

The investigators followed 114 overweight and obese subjects from a weight loss clinic in a 2-stage process. 1) A 24-week dietary intervention. The subjects self-selected whether to follow a standardized ketogenic diet (n = 53), or a personalised low-glycemic index (GI) nutrigenetic diet utilising information from 28 single nucleotide polymorphisms (n = 61). 2) After the 24-week diet period, the subjects were monitored for an additional 18 months using standard guidelines for the Keto group vs standard guidelines modified by nutrigenetic advice for the low-Glycaemic Index nutrigenetic diet (lowGI/NG) group.

RESULTS

After 24 weeks, the keto group lost more weight: - 26.2 ± 3.1 kg vs - 23.5 ± 6.4 kg (p = 0.0061). However, at 18-month follow up, the subjects in the low-GI nutrigenetic diet had lost significantly more weight (- 27.5 ± 8.9 kg) than those in the ketogenic diet who had regained some weight (- 19.4 ± 5.0 kg) (p < 0.0001). Additionally, after the 24-week diet and 18-month follow up the low-GI nutrigenetic diet group had significantly greater (p < 0.0001) improvements in total cholesterol (ketogenic - 35.4 ± 32.2 mg/dl; low-GI nutrigenetic - 52.5 ± 24.3 mg/dl), HDL cholesterol (ketogenic + 4.7 ± 4.5 mg/dl; low-GI nutrigenetic + 11.9 ± 4.1 mg/dl), and fasting glucose (ketogenic - 13.7 ± 8.4 mg/dl; low-GI nutrigenetic - 24.7 ± 7.4 mg/dl).

CONCLUSIONS

These findings demonstrate that the ketogenic group experienced enhanced weight loss during the 24-week dietary intervention. However, at 18-month follow up, the personalised nutrition group (lowGI/NG) lost significantly more weight and experienced significantly greater improvements in measures of cholesterol and blood glucose. This suggests that personalising nutrition has the potential to enhance long-term weight loss and changes in cardiometabolic parameters.

TRIAL REGISTRATION

NCT04330209, Registered 01/04/2020, retrospectively registered.

Combination of ACTN3 R577X and ACE I/D polymorphisms as a tool for prediction of obesity risk in children

The genetic influence in obesity prevalence is well described, but the role of genetic markers related to athletic strength/ endurance performance remains controversial. We investigated associations between obesity and the genetic polymorphisms alpha-actinin-3 (ACTN3) R577X and angiotensin-converting enzyme (ACE) I/D in schoolchildren aged 4-13 years from Southern Brazil. We collected sociodemographic data from parents through a questionnaire and conducted an anthropometric assessment. DNA was extracted from buccal cells and genotyping was performed by PCR. We found that 1.9% of the individuals were classified as low weight-for-age, 57.6% as normal weight and 40.5% as overweight/ obesity. Regarding allelic distribution, we found that 52.5% of individuals were DD, 30.8% ID, and 16.7% II for ACE; and 38.8% of individuals were RR, 40.2% RX and 21.0% XX for ACTN3. When both polymorphisms were combined, we observed a clear association between the composed genetic profile of these alleles and severe obesity in schoolchildren. Our data suggest that the combined analysis of ACTN3 R577X and ACE I/D polymorphisms may serve as a predictor for the risk of severe obesity in children. These data can contribute to a better understanding of the relationship between these polymorphisms and the body weight development of school-age children.

ACE Insertion/Deletion polymorphism (rs4646994) affects body composition in middle-aged premenopausal women with essential hypertension

This study assesses the association between angiotensin converting enzyme (ACE) I/D (rs4646994) polymorphism and body composition parameters in essential hypertension (HT) and menopausal status in Slovak women. The entire study sample comprised 575 women in two groups: 255 with HT and 320 without. Body composition parameters were measured by bioelectric impedance analyzer and ACE I/D polymorphism genotypes were detected by polymerase chain reaction. Premenopausal HT women with ACE II genotype had significantly lower body cell mass (p=0.004), extra- and intracellular water (p=0.027; p=0.004), fat free mass and muscle mass (p=0.006; P = 0.003), fat free mass index (p=0.006) and body cell mass index (p=0.003) than their ID/DD counterparts. These associations were not determined in normotensive and/or postmenopausal women. This study confirmed that ACE I/D gene polymorphism affects body composition in HT premenopausal women.

The association of insertions/deletions (INDELs) and variable number tandem repeats (VNTRs) with obesity and its related traits and complications

BACKGROUND

Despite the fact that insertions/deletions (INDELs) are the second most common type of genetic variations and variable number tandem repeats (VNTRs) represent a large portion of the human genome, they have received far less attention than single nucleotide polymorphisms (SNPs) and larger forms of structural variation like copy number variations (CNVs), especially in genome-wide association studies (GWAS) of complex diseases like polygenic obesity. This is exemplified by the vast amount of review papers on the role of SNPs and CNVs in obesity, its related traits (like anthropometric measurements, biochemical variables, and eating behavior), and its related complications (like hypertension, hypertriglyceridemia, hypercholesterolemia, and insulin resistance-collectively known as metabolic syndrome). Hence, this paper reviews the types of INDELs and VNTRs that have been studied for association with obesity and its related traits and complications. These INDELs and VNTRs could be found in the obesity loci or genes from the earliest GWAS and candidate gene association studies, like FTO, genes in the leptin-proopiomelanocortin pathway, and UCP2/3. Given the important role of the brain serotonergic and dopaminergic reward system in obesity susceptibility, the association of INDELs and VNTRs in these neurotransmitters' metabolism and transport genes with obesity is also reviewed. Next, the role of INS VNTR in obesity and its related traits is questionable, since recent large-scale studies failed to replicate the earlier positive associations. As obesity results in chronic low-grade inflammation of the adipose tissue, the proinflammatory cytokine gene IL1RA and anti-inflammatory cytokine gene IL4 have VNTRs that are implicated in obesity. A systemic proinflammatory state in combination with activation of the renin-angiotensin system and decreased nitric oxide bioavailability as found in obesity leads to endothelial dysfunction. This explains why VNTR and INDEL in eNOS and ACE, respectively, could be predisposing factors of obesity. Finally, two novel genes, DOCK5 and PER3, which are involved in the regulation of the Akt/MAPK pathway and circadian rhythm, respectively, have VNTRs and INDEL that might be associated with obesity.

SHORT CONCLUSION

In conclusion, INDELs and VNTRs could have important functional consequences in the pathophysiology of obesity, and research on them should be continued to facilitate obesity prediction, prevention, and treatment.

Gender-specific genetic associations of polymorphisms in ACE, AKR1C2, FTO and MMP2 with weight gain over a 10-year period

Weight gain, when it leads to overweight or obesity, is nowadays one of the major health problems. ACE, FTO, AKR1C2, TIMP4 and MMP2 genes have been implicated in previous studies on weight regulation. This study investigated the contribution of polymorphisms in these five candidate genes to the risk of weight gain over a 10-year time period. Two groups were selected from participants of the Doetinchem cohort study who were followed over a 10-year period: A stable weight group (±2 kg/10 year; n = 259) and a weight gainers group who increased their body weight by roughly 10 % (>8 kg/10 year; n = 237). Starting BMI was between 20 and 35 kg/m(2) and baseline age between 20 and 45 years. Selected SNPs and insert/deletion in candidate genes were measured in each group. In men, the allelic distribution of FTO rs9939609 (χ (2) p = 0.005), ACE rs4340 (χ (2) p = 0.006) and AKR1C2 rs12249281 (χ (2) p = 0.019) differed between the weight stable and weight gainers group. Interaction between FTO rs9939609 and ACE rs4340 was observed. In women, the allelic distribution of MMP2 rs1132896 differed between the weight stable and weight gainers group (χ (2) p = 0.00001). The A-allele of FTO was associated with a 1.99× higher risk of gaining weight in men (OR 1.99, p = 0.020), while in women, the C-allele of MMP2 was associated with a 2.50× higher risk of weight gain (OR 2.50, p = 0.001) over the 10-year period. We found that FTO in men and MMP2 in women are associated with weight gain over a 10-year follow-up period.

Association of CILP2 and ACE gene polymorphisms with cardiovascular risk factors in Slovak midlife women

The aim of this study is to assess the association of two polymorphisms, the cartilage intermediate layer protein 2 (CILP2) G/T and angiotensin converting enzyme (ACE) I/D, with blood pressure and anthropometrical and biochemical parameters related to the development of cardiovascular disease. The entire study sample comprised 341 women ranging in age from 39 to 65 years. The CILP2 genotypes were determined by PCR-RFLP and the ACE genotypes by PCR. The Bonferroni pairwise comparisons showed the effect of the CILP2 genotype on high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein B (apoB), apoB-to-apoA1 ratio, the total cholesterol (TC)-to-HDL-C ratio, non-HDL-C, and the LDL-C-to-HDL-C ratio (P < 0.05). Here, higher mean levels of HDL-C and lower mean levels of the remaining above mentioned lipid parameters were registered in the GT/TT genotype carriers than in GG carriers. Statistically significant association was identified between the ACE genotype and the following parameters: TC, LDL-C, and non-HDL-C (P < 0.05). The II genotype can lower serum level of TC (B = 0.40), LDL-C (B = 0.37), and non-HDL-C levels. The results of this study suggest that the minor T allele of CILP2 gene and I allele of ACE gene have a protective effect against elevated serum lipid and lipoprotein levels.

Polymorphism of ACE gene as the genetic predisposition of coronary artery disease in Eastern India

AIM

A case control study was designed to assess whether the prevalence of ACE gene polymorphism has any role in the development of CAD.

METHODS

The study included unrelated 217 cases with CAD and 255 healthy controls. PCR was done using primers followed by agarose gel electrophoresis for study of different ACE gene polymorphisms. Multiple logistic regression analysis was carried out to find association between studied genotypes and lifestyle as well as biochemical risk factors.

RESULTS

Both DD [OR: 2.16; 95%CI: (60.60-67.40)] and ID [OR: 1.48; 95%CI: (93.28-97.72)] genotypes of the ACE gene showed significant associations in the development of CAD. Coexistence of diabetes and hypertension found to be risk modifier of the disease. Tobacco intake in various forms elevates the risk of the disease among the cases with risk genotypes.

CONCLUSION

ID and DD genotypes of ACE gene came out to be predisposing factors for the CAD cases in our study population.

Circulating ACE is a predictor of weight loss maintenance not only in overweight and obese women, but also in men

BACKGROUND

Circulating angiotensin-converting enzyme (ACE) was identified as a predictor of weight loss maintenance in overweight/obese women of the Diogenes project.

OBJECTIVE

To investigate whether ACE acted also as a predictor in men of the Diogenes study and to compare it with that in women.

DESIGN

Subjects, who lost ≥ 8% of body weight induced by low-caloric diet in an 8-week weight loss period, were assigned to weight loss maintenance with dietary intervention for 6 months.

SUBJECTS

125 overweight/obese healthy men from eight European countries who completed whole intervention.

MEASUREMENTS

Concentrations and activity of serum ACE at baseline and after the 8-week weight loss, in addition to anthropometric and physiological parameters.

RESULTS

Serum ACE concentration decreased by 11.3 ± 10.6% during the weight loss period in men. A greater reduction is associated with less body weight regain during the maintenance period (r=0.227, P=0.012). ACE change was able to predict a weight regain ≤ 20% after 6 months, with an odds ratio of 1.59 (95% confidence interval (CI): 1.09-2.33, P=0.016) for every 10% reduction, which was independent of body mass index and weight loss. The prediction power was weaker in men than in women, but without a significant sex difference (P=0.137). In pooled subjects (N=218), the odds ratio was 1.96 (95% CI: 1.46-2.64, P<0.001).

CONCLUSIONS

A greater reduction of ACE during weight loss is favorable for weight maintenance in both men and women. This can offer useful information for personalized advice to improve weight loss maintenance. It also confirms the role of ACE in the metabolic pathways of weight regulation.