Association of the IL6 Gene Polymorphism with Component Features of Metabolic Syndrome in Obese Subjects

Association between Interleukin-6 Gene Polymorphism (rs1800795 and rs1800796) and Type 2 Diabetes Mellitus in a Ghanaian Population: A Case-Control Study in the Ho Municipality

Background

There is no conclusive evidence on the association between interleukin- (IL-) 6 gene polymorphism and type 2 diabetes mellitus (type 2 DM). Thus, this study is aimed at evaluating the role of rs1800795 and rs1800796 polymorphisms in the pathogenesis of type 2 DM among Ghanaians in the Ho Municipality.

Materials and Methods

We recruited into this hospital-based case-control study 174 patients with type 2 DM (75 DM alone and 99 with DM+HTN) and 149 healthy individuals between 2018 and 2020. Demographic, lifestyle, clinical, anthropometric, and haemodynamic variables were obtained. Fasting blood samples were collected for haematological, biochemical, and molecular analyses. Genomic DNA was extracted, amplified using Tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) technique, and genotyped for IL-6 gene polymorphism. Logistic regression analyses were performed to assess the association between IL-6 gene polymorphism and type 2 DM.

Results

The minor allele frequency (MAF) of the rs1800795 and rs1800796 polymorphisms was higher in DM alone (57.5%, 62.0%) and DM with HTN groups (58.3%, 65.3%) than controls (33.1%, 20.0%). Carriers of the rs1800795GC genotype (aOR = 2.35, 95% CI: 1.13-4.90, p = 0.022) and mutant C allele (aOR = 2.41, 95% CI: 1.16-5.00, p = 0.019) as well as those who carried the rs1800796GC (aOR = 8.67, 95% CI: 4.00-18.90, p < 0.001) and mutant C allele (aOR = 8.84, 95% CI: 4.06-19.26, p = 0.001) had increased odds of type 2 DM. For both polymorphisms, carriers of the GC genotype had comparable levels of insulin, HOMA-IR, and fasting blood glucose (FBG) with those who carried the GG genotype. IL-6 levels were higher among carriers of the rs1800796GC variant compared to carriers of the rs1800796GG variant (p = 0.023). The rs1800796 polymorphism, dietary sugar intake, and exercise status, respectively, explained approximately 3% (p = 0.046), 3.2% (p = 0.038, coefficient = 1.456), and 6.2% (p = 0.004, coefficient = -2.754) of the variability in IL-6 levels, suggesting weak effect sizes.

Conclusion

The GC genotype and mutant C allele are risk genetic variants associated with type 2 DM in the Ghanaian population. The rs1800796 GC variant, dietary sugar intake, and exercise status appear to contribute significantly to the variations in circulating IL-6 levels but with weak effect sizes.

The Concentrations of Interleukin-6, Insulin, and Glucagon in the Context of Obesity and Type 2 Diabetes and Single Nucleotide Polymorphisms in IL6 and INS Genes

Obesity and diabetes are a problem of modern medicine. Although the environmental factors contributing to the development of these diseases are widely known, research into genetic factors is still ongoing. At the same time, the role of inflammation in the pathophysiology of obesity and diabetes is increasingly emphasized. Therefore, the purpose of this study was to investigate the influence of two selected polymorphisms (rs1800795 and rs3842729) on the development of obesity and type 2 diabetes. In this study, 118 participants were examined, including a control group (nonobese and nondiabetic group), an obese group, and a diabetic group. Genotype analysis was performed using the PCR-RFLP method. It has been shown that in patients with the G/G genotype within the rs1800795 polymorphism (IL6), the chance of developing type 2 diabetes is several times lower compared to patients with the G/C and C/C genotypes. However, the rs3842729 polymorphism (INS) does not directly affect the risk of obesity or type 2 diabetes (T2D), although elevated insulin concentrations have been observed in obese and diabetic patients. These results confirm the impact of the rs1800795 polymorphism on the development of diabetes; however, this relationship is more complex and requires further research on other factors.

Association of Genotypes of ANGPTL3 with Vitamin D and Calcium Concentration in Cardiovascular Disease

One of the leading causes of mortality worldwide is cardiovascular disease, which is influenced by some variables, including calcium and vitamin D. This study aimed to assess the relationship between Angiopoietin-Like 3 (ANGPTL3) gene polymorphisms with vitamin D and calcium levels in cardiovascular disease (CVD) patients. In this research, 1002 people participated. Participants' anthropometric parameters, and FBG, calcium, and vitamin D were assessed. Blood samples were used to extract DNA. Taqman®-based polymerase chain reaction (PCR) was used to conduct genetic analysis for the rs10789117 and rs17458195. Statistical analysis was applied to determine differences across subgroups and the relationship between polymorphisms and disease. Age, body mass index (BMI), fasting Blood Sugar (FBG), phenylalanine ammonia-lyase (PAL), and smoking history were significantly correlated with CVD. Vitamin D was statistically associated with rs10789117 and rs17458195 in non-CVD individuals. In the moderate group, individuals with the C allele in rs10789117 showed a tenfold increase in vitamin D deficiency compared to those with the A allele. However, in rs11207997, individuals with the T allele had 5 to 6 times higher vitamin D deficiency than those with the C allele in all groups. This research demonstrates the relationship between some ANGPTL3 gene polymorphisms and complement levels in CVD patients. It may be concluded that individuals carrying these variants would likely benefit from using vitamin D and calcium supplements to avoid CVD.

Urine levels of estrogen and its metabolites in premenopausal middle-aged women with different degrees of obesity and their correlation with glucose and lipid metabolism

Objectives

To determine the levels of estrogen and estrogen metabolites in the urine of premenopausal women with obesity and their correlation with glucose and lipid metabolism.

Methords

135 premenopausal women were selected from the same area. According to the body mass index (BMI), they were divided into four different groups. High performance liquid chromatography-mass spectrometry (HPLC/MS) was adopted to detect the concentrations of estrogen and estrogen metabolites in the urine. The influencing factors of BMI were analyzed, the correlation between the urinary degrees of estrogen and estrogen metabolites and glucose and lipid metabolism levels was assessed.

Results

(1) The concentrations of 17β-estradiol (E2), estrone (E1), 16α-hydroxyestrone (16α-OHE1) and 2-hydroxyestrone (2-OHE1) gradually increased with increasing BMI (p < 0.05). (2) Stepwise regression analysis displayed that the concentrations of E2, 16α-OHE1 and 2-OHE1 in urine were significantly positively correlated with BMI (p < 0.05). (3) The concentrations of E2, E1, 16α-OHE1, 2-OHE1 and 16α-OHE1/2-OHE1 in urine were greatly positively related to fasting insulin (FIN), Triglyceride (TG), Total Cholesterol (TC) and Low-density lipoprotein (LDL) (p < 0.05). And they were greatly negatively related to High-density lipoprotein (HDL) (p < 0.05).

Conclusions

Early screening can reflect the degree of obesity and glucose and lipid metabolism disorders in premenopausal middle-aged women, thereby providing guidance for improving the prognosis of obese women.

A Comprehensive Summary of the Current Understanding of the Relationship between Severe Obesity, Metabolic Syndrome, and Inflammatory Status

At present, obesity, as a part of metabolic syndrome, represents the leading factor for disability, and is correlated with higher inflammation status, morbidity, and mortality. The purpose of our study is to add new insights to the present body of knowledge regarding the correlations between chronic systemic inflammation and severe obesity, which cannot be treated without considering other metabolic syndrome conditions. Biomarkers of high-level chronic inflammation are recognized as important predictors of pro-inflammatory disease. Besides the well-known pro-inflammatory cytokines, such as WBCs (white blood cells), IL-1 (interleukin-1), IL-6 (interleukin-6), TNF-alpha (tumor necrosis factor-alpha), and hsCRP (high-sensitivity C-reactive protein), as well as anti-inflammatory markers, such as adiponectin and systemic inflammation, can be determined by a variety of blood tests as a largely available and inexpensive inflammatory biomarker tool. A few parameters, such as the neutrophil-to-lymphocyte ratio; the level of cholesterol 25-hydroxylase, which is part of the macrophage-enriched metabolic network in adipose tissue; or levels of glutamine, an immune-metabolic regulator in white adipose tissue, are markers that link obesity to inflammation. Through this narrative review, we try to emphasize the influence of the weight-loss process in reducing obesity-related pro-inflammatory status and associated comorbidities. All data from the presented studies report positive results following weight-loss procedures while improving overall health, an effect that lasts over time, as far as the existing research data show.

Association of a Healthy Lifestyle with All-Cause, Cause-Specific Mortality and Incident Cancer among Individuals with Metabolic Syndrome: A Prospective Cohort Study in UK Biobank

This study investigated the association between a healthy lifestyle with all-cause, cause-specific mortality, and cancer incidence among individuals with metabolic syndrome (MetS). Healthy lifestyle scores were created based on MetS management guidelines, including never/quitting smoking, moderate drinking, good sleep, healthy diet, sufficient exercise, social support, and less sedentary behaviour. Weighted healthy lifestyle scores were further constructed and classified into three groups: unfavourable (lowest quintile), intermediate (quintiles 2−4), and favourable (highest quintile) lifestyles. We included 87,342 MetS participants from the UK Biobank. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using multivariate-adjusted Cox proportional hazards regression. During a median follow-up of 12.54 years, 6739 deaths were reported; during a median follow-up of 10.69 years, 10,802 new cancer cases were documented. We found a favourable lifestyle was inversely associated with all-cause mortality (HR: 0.57; 95%CI: 0.53−0.62), cause-specific mortality from respiratory disease, cancer, digestive disease, cardiovascular disease (HR < 1; p-trend < 0.001), and overall cancer incidence (HR: 0.84; 95% CI: 0.79−0.90). Our results indicate that adherence to healthy lifestyles is associated with lower overall cancer incidence and all-cause mortality risk among MetS individuals. However, causality cannot be made due to the nature of observational studies.

Development of a genetic risk score for obesity predisposition evaluation

Obesity is a major public health issue resulting from an interaction between genetic and environmental factors. Genetic risk scores (GRSs) are useful to summarize the effects of many genetic variants on obesity risk. In this study, we aimed to assess the association of previously well-studied genetic variants with obesity and develop a genetic risk score to anticipate the risk of obesity development in the Iranian population. Among 968 participants, 599 (61.88%) were obese, and 369 (38.12%) were considered control samples. After genotyping, an initial screening of 16 variants associated with body mass index (BMI) was performed utilizing a general linear model (p < 0.25), and seven genetic variants were selected. The association of these variants with obesity was examined using a multivariate logistic regression model (p < 0.05), and finally, five variants were found to be significantly associated with obesity. Two gene score models (weighted and unweighted), including these five loci, were constructed. To compare the discriminative power of the models, the area under the curve was calculated using tenfold internal cross-validation. Among the studied variants, ADRB3 rs4994, FTO rs9939609, ADRB2 rs1042714, IL6 rs1800795, and MTHFR rs1801133 polymorphisms were significantly associated with obesity in the Iranian population. Both of the constructed models were significantly associated with BMI (p < 0.05) and the area under the mean curve of the weighted GRS and unweighted GRS were 70.22% ± 0.05 and 70.19% ± 0.05, respectively. Both GRSs proved to predict obesity and could potentially be utilized as genetic tools to assess the obesity predisposition in the Iranian population. Also, among the studied variants, ADRB3 rs4994 and FTO rs9939609 polymorphisms have the highest impacts on the risk of obesity.

IL-6 Polymorphisms Are Not Related to Obesity Parameters in Physically Active Young Men

Interleukin 6 (IL-6) is a cytokine with both pro- and anti-inflammatory actions, but is also considered as a "metabolic hormone" involved in immune responses, affecting glucose, protein and lipid metabolism. It has been proposed to be related to obesity, but various results have been presented. Thus, in this study, the very homogenous population of young, male military professionals, living in the same conditions involving high physical activity, has been selected to avoid the influence of environmental factors. The subjects were divided into groups depending on the obesity parameters BMI (body mass index) and fat percentage (fat%), and the following IL-6 SNPs (Single Nucleotide Polymorphisms) were analyzed: rs1800795, rs1800796 and rs13306435. No relation was found between obesity parameters and IL-6 polymorphisms rs1800795, rs1800796 and rs13306435. It may be postulated that even if a genetic predisposition involves IL-6 genes, this effect in individuals with obesity of a low grade is minor, or can be avoided or at least markedly reduced by changes in lifestyle.

Novel insights into the pathological mechanisms of metabolic related dyslipidemia

Due to the technological advances, it has been well-established that obesity is strongly correlated with various health problems. Among these problems, dyslipidemia is one of the most important concomitant symptoms under obese status which is the main driving force behind the pathological progression of cardio-metabolic disorder diseases. Importantly, the type of dyslipidemia, arising from concerted action of obesity, has been identified as "metabolic related dyslipidemia", which is characterized by increased circulating levels of Low density lipoprotein cholesterol (LDL-C), Triglycerides (TG) accompanied by lower circulating levels of High density lipoprotein cholesterol (HDL-C). On the other hand, the metabolic related dyslipidemia is being verified as a vital link between obesity and hypertension, diabetes mellitus, and Cardiovascular disease (CVD). In this review, we summarized the current understanding of metabolic related dyslipidemia and the potential mechanisms which lead to the pathogenesis of obesity. Meanwhile, we also summarized the emerging results which focused on several novel lipid bio-markers in metabolic related dyslipidemia, such as pro-protein convertase subtilisin/kexin type 9 (PCSK9) and sphingosine-1-phosphate (S1P), and their potential use as biomarkers of metabolic related dyslipidemia.

Pathology of metabolically-related dyslipidemia

It is well established that overweight/obesity is closely associated with multiple health problems. Among these, dyslipidemia is the most important and main driving force behind pathologic development of cardio-metabolic disorders such as diabetes mellitus, atherosclerotic-related cardiovascular disease and hypertension. Notably, a subtype of dyslipidemia, metabolic related dyslipidemia, is now recognized as a vital link between obesity and multiple different cardiovascular diseases. This condition is characterized by increased low density lipoprotein cholesterol (LDL-C) and triglyceride (TG) and very low density lipoprotein cholesterol (VLDL-C) as well as decreased high density lipoprotein cholesterol (HDL-C) in serum. In this review, we summarize the current understanding of metabolic related dyslipidemia and the potential mechanisms which lead to the pathogenesis of obesity/overweight. We focus on several novel lipid biomarkers such as pro-protein convertase subtilisin/kexin type 9 (PCSK9) and sphingosine-1-phosphate (S1P) and their potential use as biomarkers of metabolic related dyslipidemia.

FABP1 gene variant associated with risk of metabolic syndrome

BACKGROUND

Metabolic Syndrome (MetS) is defined by a clustering of metabolic abnormalities associated with an increased risk of cardiovascular disease and type 2 diabetes mellitus. There has been an increasing interest in the associations of genetic variants involved in diabetes and obesity in the FABP1 pathway. The relationship between the rs2241883 polymorphism of FABP1 and risk of MetS remains unclear.

OBJECTIVE

We aimed to examine the association between this genetic polymorphism and the presence of MetS and its constituent factors.

METHODS

A total of 942 participants were recruited as part of the Mashhad Stroke and Heart Atherosclerosis Disorders (MASHAD study) Cohort. Patients with MetS were identified using the International Diabetes Federation (IDF) criteria (n=406) and those without MetS (n=536) were also recruited. DNA was extracted from peripheral blood samples and used for genotyping of the FABP1 rs2241883T/C polymorphism using Tetra-Amplification Refractory Mutation System Polymerase Chain Reaction (Tetra-ARMS PCR). Genetic analysis was confirmed by gel electrophoresis and DNA sequencing.

RESULTS

Using both univariate and multivariate analyses after adjusting for age, sex and physical activity, carriers of C allele (CT/CC genotypes) in FABP1 variant were related to an increased risk of MetS, compared to non-carriers (OR: 1.38, 95%CI: 1.04,1.82, p=0.026).

CONCLUSION

The present study shows that C allele in the FABP1 variant can be associated with an increased risk of MetS. The evaluation of these factors in a larger population may help further confirm these findings.

Prostaglandin Endoperoxide H Synthase-2 (PGHS-2) Variants and Risk of Obesity and Microvascular Dysfunction Among Tunisians: Relevance of rs5277 (306G/C) and rs5275 (8473T/C) Genetic Markers

The purpose of this study was to determine the impact of six PGHS-2 genetic variants on obesity development and microvascular dysfunction. The study included 305 Tunisian subjects (186 normal weights, 35 overweights and 84 obeses). PCR analyses were used for allelic discrimination between polymorphisms. Prostaglandin (PGE2, PGI2), leptin, and matrix metalloproteinase (MMP1, 2, 3, 9) levels were evaluated by ELISA. Fatty acid composition was performed by gas chromatography-mass spectrometry. Our results revealed that subjects carrying the PGHS-2 306CC (rs5277) and 8473CC (rs5275) genotypes present higher anthropometric values compared to wild-type genotypes (306GG, BMI (Kg/m²): 27.11 ± 0.58; WC (cm): 93.09 ± 1.58; 306CC, BMI: 33.83 ± 2.46; WC: 109.93 ± 5.41; 8473TT, BMI: 27.75 ± 0.68; WC: 93.96 ± 1.75; 8473CC, BMI: 33.72 ± 2.2; WC: 117.89 ± 2.94). A reduced microvascular reactivity and a higher PGE2 level were also found in individuals with the 306CC and 8473CC genotypes in comparison to 306GG and 8473TT carriers (306GG, Peak Ach-CVC (PU/mmHg): 0.46 ± 0.03; PGE2 (pg/ml): 7933.1 ± 702; 306CC, Peak Ach-CVC: 0.24 ± 0.01; PGE2: 13,380.3 ± 966.2; 8473TT, Peak Ach-CVC: 0.48 ± 0.05; PGE2: 7086.41 ± 700.31; 8473CC, Peak Ach-CVC: 0.23 ± 0.01; PGE2: 13,175.7 ± 1165.8). Fatty acid analysis showed a significant increase of palmitic acid (PA) (34.2 ± 2.09 vs. 16.82% ± 1.76, P < 0.001), stearic acid (SA) (25.76 ± 3.29 vs. 9.05% ± 2.53, P < 0.001), and linoleic acid (LA) (5.25 ± 1.18 vs. 0.5% ± 0.09, P < 0.001) levels in individuals carrying the PGHS-2 306CC genotype when compared to GG genotype individuals. Subjects with the 8473CC genotype showed also a significant increase of PA, SA ,and LA levels when compared to TT genotype carriers (PA: 38.02 ± 1.51 vs. 12.65% ± 1.54, P < 0.001; SA: 32.96 ± 1.87 vs. 1.38% ± 0.56, P < 0.001; LA: 26.84 ± 2.09 vs. 3.7% ± 1.54, P < 0.001). Logistic regression analysis revealed that PGHS-2 306CC and 8473CC variants are significantly associated with obesity status (OR 6.25, CI (1.8-21.6), P = 0.004; OR 3.01, CI (1.13-8.52), P = 0.03, respectively). Haplotypes containing the C₃₀₆:T₈₄₇₃ (OR 2.91; P = 0.01) and G_306:C₈₄₇₃ (OR 5.25; P = 0.002) combinations were associated with an enhanced risk for obesity development in the studied population. In conclusion, our results highlight that PGHS-2 306G/C and 8473T/C variants could be useful indicators of obesity development, inflammation, and microvascular dysfunction among Tunisians.

Emerging functions of adipokines in linking the development of obesity and cardiovascular diseases

Increasing evidence shows that obesity is the critical factor in shaping cardio-metabolic phenotypes. However, the pathogenic mechanisms remain incompletely clarified. According to the published reports, adipose tissue communicates with several diverse organs, such as heart, lungs, and kidneys through the secretion of various cytokines named adipokines. The adipocytes isolated from obese mice or humans are dysfunctional with aberrant production of pro-inflammatory adipokines, which subsequently induce both acute and chronic inflammatory reaction and facilitate the process of cardio-metabolic disorder complications. Furthermore, the microenvironment within adipose tissue under obese status also influence the secretion of adipokines. Recently, given that several important adipokines have been completely researched and causally involved in various diseases, we could make a conclusion that adipokines play an essential role in modulating the development of cardio-metabolic disorder diseases, whereas several novel adipokines continue to be explored and elucidated. In the present review, we summarized the current knowledge of the microenvironment of adipose tissue and the published mechanisms whereby adipocytes affects obesity and cardiovascular diseases. On the other hand, we also provide the evidence to elucidate the functions of adipokines in controlling and regulating the inflammatory reactions which contribute to obesity and cardiovascular disease.

Association between obesity categories with cardiovascular disease and its related risk factors in the MASHAD cohort study population

Background

Cardiovascular disease (CVD) is a significant cause of morbidity and mortality globally. Obesity is an important CVD risk factor and is increasing in prevalence.

Methods

In this study, 3829 men and 5720 women (35‐65 years) were enrolled as part of the MASHAD cohort study. Four categories were identified according to body mass index and waist circumference that was defined by the World Health Organization. Logistic regression analysis was used to determine the adjusted odds ratio (OR) for the occurrence of CVD, and Cox regression model was used to evaluate the association of obesity with CVD incidence.

Results

We found that the higher risk groups defined by categories of adiposity were significantly related to a higher prevalence of a high serum total cholesterol (TC), and triglycerides (TG), and lower high‐density lipoprotein cholesterol (HDL), and higher fasting blood glucose (FBG) in both genders and a higher low‐density lipoprotein cholesterol (LDL) in women (P < .001). Additionally, a high percentage of participants with dyslipidemia, high LDL, high TC, and low HDL and a high percentage of participants with metabolic syndrome, diabetes, hypertension, and a high serum TG were observed across obesity categories (P < .001). Moreover, women with the very high degrees of obesity had a greater risk of CVD (HR: 1.91, 95% CI: 1.06‐3.43, P = .03).

Conclusion

Obesity strongly predicts several CVD risk factors. Following 6 years of follow‐up, in individuals within increasing degrees of obesity, there was a corresponding significant increase in CVD events, rising to approximately a twofold higher risk of cardiovascular events in women compared with men.

Association between the serum concentrations of 12 cytokines and growth factors and metabolic syndrome in patients undergoing angiography

We aimed to compare the concentrations of serum cytokines in patients undergoing coronary angiography and finding their possible associations with metabolic syndrome. Twelve serum cytokines and growth factors (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, MCP-1, IFN-γ, EGF, and VEGF) were measured by sandwich chemiluminescence assays, on the Evidence Investigator^® system. There were significant differences regarding sex, height, weight, BMI, WC, HC, FPG, TG and HDL-C between those with and without MetS in patients undergoing angiography (p < .05). Serum concentrations of IL-6 and INF-γ were significantly higher in subjects with MetS, compared to those without MetS (p = .031 and p = .035, respectively). However, only serum IL-6 was associated with the presence of MetS (β = 1.215, CI = 1.047-1.409, p = .010). From several serum cytokines and growth factors assessed in patients, IL-6 was the only serum cytokine that was significantly different between those with and without MetS after correction for confounding factors.