Association between inflammatory obesity phenotypes, FTO-rs9939609, and cardiovascular risk factors in patients with type 2 diabetes

The Microbiota and Evolution of Obesity

Obesity is a major global concern and is generally attributed to a combination of genetic and environmental factors. Several hypotheses have been proposed to explain the evolutionary origins of obesity epidemic, including thrifty and drifty genotypes, and changes in thermogenesis. Here, we put forward the hypothesis of metaflammation, which proposes that due to intense selection pressures exerted by environmental pathogens, specific genes that help develop a robust defense mechanism against infectious diseases have had evolutionary advantages and that this may contribute to obesity in modern times due to connections between the immune and energy storage systems. Indeed, incorporating the genetic variations of gut microbiota into the complex genetic framework of obesity makes it more polygenic than previously believed. Thus, uncovering the evolutionary origins of obesity requires a multifaceted approach that considers the complexity of human history, the unique genetic makeup of different populations, and the influence of gut microbiome on host genetics.

Fat Mass and Obesity-Related (FTO) Gene Variant Is a Predictor of CVD in T2DM Patients

Background: The role of the common FTO gene variant rs9939609 in obesity has been well established, and the FTO gene has a strong association with T2DM. Objective: To investigate the association of FTO gene variant rs9939609 with obesity-related parameters in T2DM and CVD patients. Materials and Methods: In this cross-sectional study, 280 subjects of either sex aged 45.10 ± 9.6 years were randomly divided into four groups, that is, T2DM, T2DM with CVD, nondiabetic with CVD disease, and normal control. These samples were genotyped by ARMS-PCR. The FTO gene association with obesity-related parameters in T2DM and CVD patients was analyzed by SPSS 22. Results: The TT genotype was the most common genotype (46.80%) in our study groups. The minor allele frequency (MAF) was significantly higher in T2DM patients (0.39 vs. 0.28), T2DM patients with CVD (0.43 vs. 0.28), and nondiabetic patients with CVD (0.35 vs. 0.28) as compared to control with p < 0.005. Carriers of the AA genotype of the FTO gene rs9939609 were significantly associated with increased BMI, WC, HbA1C, SBP, DBP, and TGs and lowered HDL cholesterol as compared to the TA and TT genotypes in T2DM and CVD patients with p < 0.005. The FTO gene variant rs9939609 showed a significant association with T2DM and CVD. The AA genotype odds ratio (OR) in T2DM was 1.48 (1.06-2.32), p = 0.006, and in CVD, it was 1.56 (1.04-2.4), p = 0.003. Conclusion: The FTO gene variant rs9939609 has a strong association with T2DM and CVD. The AA genotype of FTO gene variants rs9939609 showed a strong association with most of the risk factors of CVD and T2DM.

The association between healthy eating index-2015 with anthropometric, cardiometabolic and hepatic indices among patients with non-alcoholic fatty liver disease

BACKGROUND

Obesity, cardiovascular diseases, and metabolic disorders are common problems among participants with non-alcoholic fatty liver disease (NAFLD). However, the association between these problems and the healthy eating index-2015 (HEI-2015) remains unknown. Although the HEI-2015 originated from American dietary guidelines, its comprehensive evaluation of diet quality provides valuable insights for various populations, including Iranians. Therefore, the objective of this study was to investigate the association between anthropometric, hepatic, and cardio-metabolic indices with HEI-2015 scores in participants with NAFLD.

METHODS

We conducted a cross-sectional analysis of data from the Hoveyzeh Cohort Study, which included adults aged 35 to 70 years between 2016 and 2018. A total of 664 participant with NAFLD (452 females and 212 males) were included in the analysis. The HEI-2015 was assessed using the Food Frequency Questionnaire (FFQ). Various indices, including the body shape index (ABSI), atherogenic index of plasma (AIP), visceral adiposity index (VAI), lipid accumulation product (LAP), cardiometabolic index (CMI), lipoprotein combine index (LCI), AST/ALT ratio, ALD/NAFLD index, and hepatic steatosis index (HSI), were calculated.

RESULTS

No significant differences were observed in anthropometric, cardio-metabolic, and hepatic indices across the quartiles of HEI-2015. However, among participants with NAFLD, men had significantly higher AIP and LCI levels, while women had significantly higher BMI, ABSI, VAI, LAP, and CMI levels. Additionally, women with NAFLD exhibited higher AST/ALT and HSI levels but lower ALD/NAFLD levels compared to men with NAFLD. Linear regression analysis among men with NAFLD revealed a significant negative correlation between HEI-2015 score and HSI in both the unadjusted model (β=-0.131, SE = 0.058, p = 0.024) and the adjusted model for energy intake (β=-0.129, SE = 0.058, p = 0.028).

CONCLUSION

The present study demonstrated a correlation between lower HEI-2015 scores and an increased risk of steatosis in men with NAFLD. Moreover, our findings highlighted gender-related differences in NAFLD and cardio-metabolic disorders.

Association of fat mass and obesity-associated (FTO) gene polymorphisms with non-communicable diseases (NCDs) in the Iranian population: A systematic review of observational studies

Background

Single nucleotide polymorphisms have been implicated in various diseases, most notably non-communicable diseases (NCDs). The aim of this study was to review available evidence regarding associations between FTO polymorphisms and NCDs in the Iranian population.

Methods

A comprehensive search was conducted through PubMed/Medline and Scopus databases up to December 2021, as well as reference lists of pertinent articles and key journals. All observational studies that examined the association between FTO gene polymorphisms and NCDs in the Iranian population were included. There was no limitation on the publication year. The Newcastle-Ottawa Scale (NOS) was used to assess the study's quality.

Results

The initial search yielded 95 studies, of which 30 studies were included in the current systematic review. The underlying disorders were obesity, type 2 diabetes, breast and colorectal cancers, depression, and metabolic syndrome. These studies found an association between FTO gene polymorphisms and obesity in the Iranian population, but the relationship with other NCDs was debatable. Even though, other diseases such as diabetes and metabolic syndrome, which are closely related to obesity, may also be associated with FTO gene polymorphisms.

Conclusion

FTO gene polymorphism appears to play a role in the occurrence of NCDs. Some of the study results may be misleading due to ethnic differences and the effect of other genetic factors on disease onset, which needs to be investigated further. Finally, FTO gene polymorphisms can be studied as a preventive or therapeutic target.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01139-4.

The Impact of Variants in Four Genes: MC4R, FTO, PPARG and PPARGC1A in Overweight and Obesity in a Large Sample of the Brazilian Population

Obesity and overweight are worldwide public health problems with an evident genetic predisposition that is still poorly understood. In addition, great variability has been described across populations. In this work, we analyzed the association of variants in four genes: PPARG (rs1801282), PPARGC1A (rs8192678), FTO (rs9939609) and MC4R (rs17782313) with overweight and obesity in a large sample of the Brazilian population. The case-control study involved 4084 individuals (1844 with overweight or obesity; and 2240 with normal BMI). Genotyping was performed by quantitative PCR. MC4R rs17782313-C was associated with obesity (OR = 1.27, p = 0.038) and when stratifying by sex associated only in women (OR = 1.36, p = 0.030). FTO rs9939609-A allele was associated with overweight however for women it represented a risk factor (OR = 1.24, p = 0.034) and for men, a protective factor (OR = 0.68, p = 0.033). PPARG was the strongest associated gene, with both overweight and obesity, and this association was also restricted to women (rs1801282-GG OR = 1.46, p = 0.027). The combined effect of the three risk alleles on overweight and obesity had an OR of 1.65 (p = 0.008) and when stratifying by sex again it was significant only in females (OR = 1.95, p = 0.0028). Our findings indicate that the three genes play a significant role in predisposing to overweight and/or obesity in the Brazilian population, reaching together a relatively high impact on these traits. Interestingly our results also suggest a strong sex-specific genetic effect of these variants.