Epigenetic manifestation of metabolic syndrome and dietary management

Panoramic on Epigenetics in Coronary Artery Disease and the Approach of Personalized Medicine

Epigenetic modifications play a fundamental role in the progression of coronary artery disease (CAD). This panoramic review aims to provide an overview of the current understanding of the epigenetic mechanisms involved in CAD pathogenesis and highlights the potential implications for personalized medicine approaches. Epigenetics is the study of heritable changes that do not influence alterations in the DNA sequence of the genome. It has been shown that epigenetic processes, including DNA/histone methylation, acetylation, and phosphorylation, play an important role. Additionally, miRNAs, lncRNAs, and circRNAs are also involved in epigenetics, regulating gene expression patterns in response to various environmental factors and lifestyle choices. In the context of CAD, epigenetic alterations contribute to the dysregulation of genes involved in inflammation, oxidative stress, lipid metabolism, and vascular function. These epigenetic changes can occur during early developmental stages and persist throughout life, predisposing individuals to an increased risk of CAD. Furthermore, in recent years, the concept of personalized medicine has gained significant attention. Personalized medicine aims to tailor medical interventions based on an individual's unique genetic, epigenetic, environmental, and lifestyle factors. In the context of CAD, understanding the interplay between genetic variants and epigenetic modifications holds promise for the development of more precise diagnostic tools, risk stratification models, and targeted therapies. This review summarizes the current knowledge of epigenetic mechanisms in CAD and discusses the fundamental principles of personalized medicine.

Association of serum 25-hydroxyvitamin D with metabolic syndrome and type 2 diabetes: a one sample Mendelian randomization study

Background

Vitamin D deficiency has been associated with type 2 diabetes (T2D) and metabolic syndrome (MS) and its components. However, it is unclear whether a low concentration of vitamin D is the cause or consequence of these health conditions. Thus, this study aimed to evaluate the association of vitamin D concentrations and its genetic risk scores (GRSs) with MS and its component diseases, such as T2D, in middle-aged and elderly participants from rural eastern China.

Methods

A subset of 2393 middle-aged and elderly individuals were selected from 70,458 participants of the Nantong Chronic Diseases Study of 2017–2018 in China. We used two 25-hydroxyvitamin D (25[OH]D) synthesis single-nucleotide polymorphisms (SNPs) (DHCR7-rs12785878 and CYP2R1-rs10741657) and two 25(OH) D metabolism SNPs (GC-rs2282679 and CYP24A1-rs6013897) for creating GRSs, which were used as instrumental variables to assess the effect of genetically lowered 25(OH) D concentrations on MS and T2D based on the Wald ratio. F statistics were used to validate that the four SNPs genetically determined 25(OH) D concentrations.

Results

Compared to vitamin D sufficient individuals, individuals with vitamin D insufficiency had an odds ratio (OR [95% confidence interval {CI}]) of MS of 1.30 (1.06–1.61) and of T2D of 1.32 (1.08–1.64), individuals with vitamin D deficiency had an ORs (95% CI) of MS of 1.50 (1.24–1.79) and of T2D of 1.47 (1.12–1.80), and those with vitamin D severe deficiency had an ORs (95% CI) of MS of 1.52 (1.29–1.85) and of T2D of 1.54 (1.27–1.85). Mendelian randomization analysis showed a 25-nmol/L decrease in genetically instrumented serum 25(OH) D concentrations using the two synthesis SNPs (DHCR7 and CYP2R1 genes) associated with the risk of T2D and abnormal diastolic blood pressure (DBP) with ORs of 1.10 (95%CI: 1.02–1.45) for T2D and 1.14 (95%CI: 1.03–1.43) for DBP.

Conclusions

This one sample Mendelian randomization analysis shows genetic evidence for a causal role of lower 25(OH) D concentrations in promoting of T2D and abnormal DBP in middle-aged and elderly participants from rural China.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-021-02307-6.

Elucidation of Epigenetic Landscape in Coronary Artery Disease: A Review on Basic Concept to Personalized Medicine

Despite extensive clinical research and management protocols applied in the field of coronary artery diseases (CAD), it still holds the number 1 position in mortality worldwide. This indicates that we need to work on precision medicine to discover the diagnostic, therapeutic, and prognostic targets to improve the outcome of CAD. In precision medicine, epigenetic changes play a vital role in disease onset and progression. Epigenetics is the study of heritable changes that do not affect the alterations of DNA sequence in the genome. It comprises various covalent modifications that occur in DNA or histone proteins affecting the spatial arrangement of the DNA and histones. These multiple modifications include DNA/histone methylation, acetylation, phosphorylation, and SUMOylation. Besides these covalent modifications, non-coding RNAs-viz. miRNA, lncRNA, and circRNA are also involved in epigenetics. Smoking, alcohol, diet, environmental pollutants, obesity, and lifestyle are some of the prime factors affecting epigenetic alterations. Novel molecular techniques such as next-generation sequencing, chromatin immunoprecipitation, and mass spectrometry have been developed to identify important cross points in the epigenetic web in relation to various diseases. The studies regarding exploration of epigenetics, have led researchers to identify multiple diagnostic markers and therapeutic targets that are being used in different disease diagnosis and management. Here in this review, we will discuss various ground-breaking contributions of past and recent studies in the epigenetic field in concert with coronary artery diseases. Future prospects of epigenetics and its implication in CAD personalized medicine will also be discussed in brief.

Metabolic syndrome in a sample of Egyptian adolescent girls and its association with apolipoprotein E

AIM

Obesity and its metabolic complications are increasing in childhood and extend to adulthood. The aims of this study were to assess the prevalence of metabolic syndrome (MS) in a sample of Egyptian adolescent girls and investigate its association with apolipoprotein E.

METHODS

A cross-sectional study design was used, including 200 Egyptian adolescent girls aged between 12 and 18 years. They were subjected to blood pressure (BP) measurement, anthropometric measurements (weight, height and waist circumference (WC)), laboratory investigations (fasting glucose and lipid profile) and molecular analysis (Apo E).

RESULTS

Overweight/obese girls were suffering significantly, more than normal-weight girls, from hypertension (66.7 vs. 40.8%), diabetes diagnosed by elevated fasting blood glucose (46.7 vs. 31.2%) and low high-density lipoprotein (HDL) (64 vs. 59.2%). Girls with MS had significantly higher values of body mass index Z-score, WC, BP, cholesterol and triglycerides and significantly lower HDL. Allele E3 (59.1 vs. 55.1%) was more frequent among girls with MS, while allele E4 (41 vs. 36.4) was more frequent among girls without MS. MS was the most prominent among girls with the E3/E4 genotype (35.7%), who had the highest frequency of elevated cholesterol, triglycerides, low-density lipoprotein and blood glucose, while girls with the E2/E4 genotype, which was rare among both groups, had the highest frequency of elevated BP (68.8%) and low HDL (71.4%).

CONCLUSION

MS was significantly more prominent among overweight/obese adolescent girls with the E3/E4 genotype, who had the highest frequency of disturbed lipid profile and blood glucose.

Di-peptidyl peptidase-4 inhibitor sitagliptin protects vascular function in metabolic syndrome: possible role of epigenetic regulation

Metabolic syndrome (MetS) is a complex medical disorder characterized by insulin resistance, hypertension, and high risk of coronary disease and stroke. Microvascular rarefaction and endothelial dysfunction have also been linked with MetS, and recent evidence from clinical studies supports the efficacy of incretin-based antidiabetic therapies for vascular protection in diabetes. Previous studies pointed out the importance of dipeptidyl peptidase-4 (DPP-4) inhibition in endothelial cells due to getting protection against metabolic pathologies. We therefore aimed to investigate the acute effects of a DPP-4 inhibitor, sitagliptin, on vascular function in rats with high-sucrose diet-induced MetS. In order to elucidate the mechanisms implicated in the effects of DPP-4 inhibition, we tested the involvement of NO pathway and epigenetic regulation in the MetS. Acute use of sitagliptin protects the vascular function in the rats with MetS in part due to NO pathway via restoring the depressed aortic relaxation responses mediated by receptors. Application of sitagliptin enhanced the depressed phosphorylation levels of both the endothelial NO synthase and the apoptotic status of protein kinase B, known as Akt, in endothelium-intact thoracic aorta from rats with MetS. One-hour application of sitagliptin on aortic rings from rats with MetS also induced remarkable histon posttranslational modifications such as increased expression of H3K27Me3, but not of H3K27Me2, resulting in an accumulation of the H3K27Me3. Our findings suggest that, in addition to its well-known hypoglycemic action, sitagliptin may also have beneficial effects on hyperglycemia-induced vascular changes in an endotheium-dependent manner. These present results with sitagliptin aside from the glycaemic control, may demonstrate its important role in the treatment of patients with MetS.

Lack of association of apolipoprotein E (Apo E) polymorphism with the prevalence of metabolic syndrome: the National Heart, Lung and Blood Institute Family Heart Study

OBJECTIVE

Metabolic syndrome (MetS), characterized by abdominal obesity, atherogenic dyslipidaemia, elevated blood pressure and insulin resistance, is a major public health concern in the United States. The effects of apolipoprotein E (Apo E) polymorphism on MetS are not well established.

METHODS

We conducted a cross-sectional study consisting of 1551 participants from the National Heart, Lung and Blood Institute Family Heart Study to assess the relation of Apo E polymorphism with the prevalence of MetS. MetS was defined according to the American Heart Association-National Heart, Lung and Blood Institute-International Diabetes Federation-World Health Organization harmonized criteria. We used generalized estimating equations to estimate adjusted odds ratios (ORs) for prevalent MetS and the Bonferroni correction to account for multiple testing in the secondary analysis.

RESULTS

Our study population had a mean age (standard deviation) of 56.5 (11.0) years, and 49.7% had MetS. There was no association between the Apo E genotypes and the MetS. The multivariable adjusted ORs (95% confidence interval) were 1.00 (reference), 1.26 (0.31-5.21), 0.89 (0.62-1.29), 1.13 (0.61-2.10), 1.13 (0.88-1.47) and 1.87 (0.91-3.85) for the Ɛ3/Ɛ3, Ɛ2/Ɛ2, Ɛ2/Ɛ3, Ɛ2/Ɛ4, Ɛ3/Ɛ4 and Ɛ4/Ɛ4 genotypes, respectively. In a secondary analysis, Ɛ2/Ɛ3 genotype was associated with 41% lower prevalence odds of low high-density lipoprotein [multivariable adjusted ORs (95% confidence interval) = 0.59 (0.36-0.95)] compared with Ɛ3/Ɛ3 genotype.

CONCLUSIONS

Our findings do not support an association between Apo E polymorphism and MetS in a multicentre population-based study of predominantly White US men and women.

The diet-induced metabolic syndrome is accompanied by whole-genome epigenetic changes

Consuming a high-fat/high-fructose diet (HFD) starting at a young age leads to the development of obesity and to the progression of metabolic syndrome (MS). We are interested in the relationship between MS and DNA methylation as a mediator of the metabolic memory and the early appearance of these diseases in the progeny. To this end, Wistar rats were fed a HFD for 1 year, and every 12 weeks, biochemical analyses were performed. After 24 weeks, animals fed the HFD showed alterations related to MS such as elevated blood levels of fasting glucose, triglycerides, and insulin compared with their littermate controls. During the experimental period, the control females exhibited a 40 % lower 5-methylcytosine (5-mC) level compared to the control males. The HFD affected the 5-mC levels in males and females differently. The HFD induced a 20 % decrease in the 5-mC levels in males and a 15 % increase in females. We found that the HFD induces an early presentation of MS in the progeny of treated animals and that the DNA methylation was altered in the F1 generation. The presentation of MS is positively associated with changes in the global percentage of 5-mC in the DNA.

Decreased global DNA methylation in the white blood cells of high fat diet fed vervet monkeys (Chlorocebus aethiops)

Epigenetic mechanisms are associated with the development of many chronic diseases and due to their reversible nature offer a unique window of opportunity to reverse the disease phenotype. This study investigated whether global DNA methylation correlates with dysglycemia in the vervet monkey (Chlorocebus aethiops). Diet-induced changes in DNA methylation were observed where global DNA methylation was twofold lower in monkeys fed a high fat diet (n = 10) compared to monkeys fed a standard diet (n = 15). An inverse correlation was observed between DNA methylation, blood glucose concentrations, bodyweight, and age, although the association was not statistically significant. Consumption of a high fat diet is associated with the development of metabolic disease; thus, these results suggest the use of global DNA methylation as a biomarker to assess the risk for metabolic disease. Moreover, this study provides further support for the use of the vervet monkey as a model system to study metabolic diseases such as type 2 diabetes. Integration of altered DNA methylation profiles into predictive models could facilitate risk stratification and enable intervention strategies to inhibit disease progression. Such interventions could include lifestyle modifications, for example, the increased consumption of functional foods with the capacity to modulate DNA methylation, thus potentially reversing the disease phenotype and preventing disease.

Factors influencing epigenetic mechanisms and related diseases

It is becoming clear that epigenetic mechanisms are associated with disease. To date, a myriad of epigenetic alterations, including altered DNA methylation and aberrant histone post-translational modifications, have been linked with various conditions. The most widely investigated example is the link between aberrant DNA methylation and malignancy that has lead to the clinical use of the DNA methyltransferase inhibitors, azacitidine and decitabine, for the treatment of myelodysplastic syndromes. Similarly, defective histone acetylation status has been associated with malignancy, providing the basis for the clinical use of the histone deacetylase inhibitors suberoylanilide hydroxamic acid and depsipeptide for the treatment of cutaneous T-cell lymphoma. In addition, there is an emerging association between perturbed fetal epigenetic programming and developmental origins of disease due to both nutritional and environmental factors. In particular, epigenetic events associated with metabolic syndrome have been identified. Related epigenetic mechanisms as well potential pharmacological and dietary interventions at critical periods of development form a large part of the discussion in this Forum. Further, this Forum provides an in-depth account of the association between epigenetic mechanisms and carcinogenesis with a focus on disease prevention with dietary chromatin-modifying compounds. Finally, the association between aberrant epigenetic events and neurodegenerative conditions, such as Alzheimer's disease (AD), is becoming apparent. A research article in this Forum identifies a potential new polymorphism associated with one-carbon metabolism that may contribute to the pathogenesis of AD. Overall, this Forum provides a detailed account of known epigenetic processes in developmental programming and human disease.