Epigenetic modifications, particularly histone acetylation-deacetylation and its related enzymes, such as sirtuin 1 (SIRT1) deacetylase, may have substantial roles in the pathogenesis of obesity and ...its associated health issues. This study aimed to evaluate global histone acetylation status and SIRT1 gene expression in children and adolescents with obesity and their association with metabolic and anthropometric parameters. This study included 60 children and adolescents, 30 with obesity and 30 normal-weight. The evaluation consisted of the analysis of global histone acetylation levels and the expression of the SIRT1 gene in peripheral blood mononuclear cells, by specific antibody and real-time PCR, respectively. Additionally, insulin, fasting plasma glucose, lipid profile and tumor necrosis factor alpha (TNF-alpha) levels were measured. Insulin resistance was assessed using the homeostasis model assessment of insulin resistance (HOMA-IR). Metabolic syndrome was determined based on the diagnostic criteria established by IDF. Individuals with obesity, particularly those with insulin resistance, had significantly higher histone acetylation levels compared to control group. Histone acetylation was positively correlated with obesity indices, TNF-alpha, insulin, and HOMA-IR. Additionally, a significant decrease in SIRT1 gene expression was found among obese individuals, which was negatively correlated with the histone acetylation level. Furthermore, SIRT1 expression levels showed a negative correlation with various anthropometric and metabolic parameters. Histone acetylation was enhanced in children and adolescents with obesity, potentially resulting from down-regulation of SIRT1, and could play a role in the obesity-associated metabolic abnormalities and insulin resistance. Targeting global histone acetylation modulation might be considered as an epigenetic approach for early obesity management.
Background Permanent neonatal diabetes mellitus (PNDM) presents with dehydration and hyperglycemia, which usually occurs during the first 12 months of life. Activating mutations of beta-cell ...adenosine triphosphate-sensitive potassium KATP channel subunits that cause opening of the channel are associated with PNDM. Some patients with PNDM respond to administration of a sulfonylurea derivative, which has long action on blood glucose even during hypoglycemia and has an apoptotic effect on beta cells. However, there have been no reports regarding treatment with meglitinide (repaglinide), which has rapid and short duration of action during the rise in blood glucose after meals that is more similar to beta cell function. It has no effects during hypoglycemia, so it does not cause neurological damage, and has no apoptotic effect on beta cells. We report herein the effects of repaglinide administration in the management and clinical outcome of two patients with PNDM during 9 and 10 years of follow-up. Case presentation Two Iranian infants were brought to our institution with poor general condition, dehydration, lethargy, and poor feeding. They had diabetic ketoacidosis at 52 days and 3.5 months of age, respectively. Their genetic analysis revealed mutations in the KCNJ11 gene encoding KIR6.2, so they both had PNDM. After treatment of diabetic ketoacidosis with insulin, they responded to sulfonylurea (glibenclamide) treatment, but were switched to repaglinide because of blood sugar fluctuations in terms of hyper- and hypoglycemia. Repaglinide was administered with the dosage of 0.04 mg/kg/day divided before every meal. Results The patients were 10 and 9 years old at the last visit, with normal growth parameters. The values of self-monitored blood glucose were well-controlled, and the hemoglobin A1C (HbA1C) levels ranged from 3.6 to 6.4% during the follow-up period. There was no complication of diabetes, neurological disorder, or adverse effects related to repaglinide. Conclusion In every neonate or infant < 6 months of age with diabetes mellitus, PNDM should be considered. A trial of oral repaglinide can be performed and substituted for glibenclamide for prevention of hypoglycemia, neurological damage, and apoptosis of beta cells during long-term administration. Keywords: Permanent, Neonatal, Diabetes mellitus, Repaglinide, Case report
Background Excessive extracellular matrix (ECM) deposition in adipose tissue is a hallmark of fibrosis, leading to disrupted adipose tissue homeostasis and metabolic dysfunction. Hesperetin, a ...flavonoid compound, has shown promising anti-inflammatory, anti-obesity and anti-diabetic properties. Therefore, we investigated the anti-fibrotic effects of hesperetin, through targeting ECM components and matrix metalloproteinase enzymes. Methods 3T3-L1 cells were cultured in DMEM, containing 10% FBS and 1% penicillin/streptomycin. Cells were treated with a range of hesperetin concentrations, and the cell viability was determined using MTT assay. Subsequently, the expression of genes encoding collagen VI, osteopontin, matrix metalloproteinase-2 (Mmp-2) and Mmp-9 was analyzed using specific primers and real-time PCR technique. To evaluate protein levels of collagen VI and osteopontin, Western blotting was performed. Results Hesperetin affected the viability of 3T3-L1 adipocytes with IC50 of 447.4 microM, 339.2 microM and 258.8 microM (24 h, 48 and 72 h, respectively). Hesperetin significantly reduced the gene and protein expression of both collagen VI and osteopontin in 3T3-L1 pre-adipocytes, in a time- and dose-dependent manner. Hesperetin was also able to cause a remarkable decline in gene expression of Mmp2 and Mmp9. Conclusion Hesperetin could potently reduce the production of markers of adipose tissue fibrosis and might be considered a potential anti-fibrotic compound in obesity. Thus, hesperetin has the potency to be used for the treatment of obesity-associated fibrosis. Keywords: Obesity, Adipose tissue fibrosis, Hesperetin, Collagen, Osteopontin, Matrix metalloproteinase
Background. Angiopoietin-like protein 2 (ANGPTL2) is one of the adipocyte-derived inflammatory factors which connects obesity to insulin resistance. ANGPTL3 has a direct role in regulation of lipid ...metabolism. The objective of this study was to evaluate ANGPTL2 and ANGPTL3 in childhood obesity and their relationship with metabolic syndrome. Methods. 70 children and adolescents, 35 obese and 35 normal-weight subjects, were enrolled in this research after complete clinical examination and anthropometric evaluations. Serum ANGPTL2 and ANGPTL3 and insulin were measured by enzyme-linked immunosorbent assay (ELISA). Homeostatic model assessment of insulin resistance (HOMA-IR) was calculated and used to estimate insulin resistance (IR). Colorimetric methods were used for the assessment of fasting plasma glucose (FPG), LDL-C, HDL-C, total cholesterol (TC), and triglyceride (TG). Results. The levels of ANGPTL2 and ANGPTL3 were significantly higher in obese subjects than those in controls, but they did not differ significantly in subjects with or without IR. ANGPTL3 was found to be significantly elevated in obese children with metabolic syndrome (MetS) in comparison with those without MetS. Both of the studied ANGPTLs were positively correlated with BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP), TC, and LDL-C. The correlation between ANGPTL3 and either TC or LDL-C remained significant after adjusting for BMI. Conclusion. Serum ANGPTL2 and ANGPTL3 were elevated in obesity and associated with blood pressure and indices of metabolic syndrome, suggesting that they might be involved in the advancement of obesity-related hypertension and metabolic syndrome.
Introduction
Adipose triglyceride lipase (ATGL) is a crucial enzyme responsible for the release of fatty acids from various tissues. The expression of ATGL is regulated by insulin and this enzyme is ...linked to Insulin resistance (IR). On the other hand, ATGL‐mediated lipolysis is connected to macrophage function and thus, ATGL is involved in inflammation and the pathogenesis of lipid‐related disorders. This study aimed to investigate the correlation between ATGL, obesity, Metabolic Syndrome (MetS), and inflammation.
Methods
A total of 100 participants, including 50 individuals with obesity and 50 healthy participants, were recruited for this study and underwent comprehensive clinical evaluations. Blood samples were collected to measure plasma lipid profiles, glycemic indices, and liver function tests. Additionally, peripheral blood mononuclear cells (PBMCs) were isolated and used for the assessment of the gene expression of ATGL, using real‐time PCR. Furthermore, PBMCs were cultured and exposed to lipopolysaccharides (LPS) with simultaneous ATGL inhibition, and the gene expression of inflammatory cytokines, along with the secretion of prostaglandin E2 (PGE2), were measured.
Results
The gene expression of ATGL was significantly elevated in PBMCs obtained from participants with obesity and was particularly higher in those diagnosed with MetS. It exhibited a correlation with insulin levels and Homeostatic Model Assessment for IR (HOMA‐IR), and it was associated with lipid accumulation in the liver. Stimulation with LPS increased ATGL expression in PBMCs, while inhibition of ATGL attenuated the inflammatory responses induced by LPS.
Conclusions
Obesity and MetS were associated with dysregulation of ATGL. ATGL might play a role in the upregulation of inflammatory cytokines and act as a significant contributor to the development of metabolic abnormalities related to obesity.
Adipose triglyceride lipase (ATGL) was significantly increased in subjects with obesity and was associated with lipid accumulation in liver. There was also a direct relationship between ATGL and markers of insulin resistance, including insulin and HOMA‐IR. ATGL inhibition abolished the expression of inflammatory cytokines.
Ghrelin is a 28-amino acid peptide with an orexigenic property, which is predominantly produced by the stomach. Acylated ghrelin is the active form of this hormone. Obestatin is a 23-amino acid ...peptide which is produced by post-translational modification of a protein precursor that also produces ghrelin. Obestatin has the opposite effect of ghrelin on food intake. The aim of this study was to evaluate acylated ghrelin and obestatin levels and their ratio in obese and normal-weight children and adolescents, and their association with metabolic syndrome (MetS) parameters.
Serum acyl-ghrelin, obestatin, leptin, insulin, fasting plasma glucose (FPG), lipid profile, and malondialdehyde (MDA) were evaluated in 73 children and adolescents (42 obese and 31 control). Insulin resistance was calculated by a homeostasis model assessment of insulin resistance (HOMA-IR). MetS was determined according to IDF criteria.
Acyl-ghrelin levels were significantly lower in obese subjects compared to the control group and lower in obese children with MetS compared to obese subjects without MetS. Obestatin was significantly higher in obese subjects compared to that of the control, but it did not differ significantly among those with or without MetS. Acyl-ghrelin to obestatin ratio was significantly lower in obese subjects compared to that in normal subjects. Acyl-ghrelin showed significant negative and obestatin showed significant positive correlations with body mass index (BMI), BMI Z-score, leptin, insulin, and HOMA-IR. Acyl-ghrelin had a significant negative correlation with MDA as an index of oxidative stress.
Ghrelin is decreased and obestatin is elevated in obesity. Both of these hormones are associated with insulin resistance, and ghrelin is associated with oxidative stress. The balance between ghrelin and obestatin seems to be disturbed in obesity.
Nrf2 is a transcription factor that induces the expression of several proteins with antioxidant properties such as sestrin2 (Sesn2) and is therefore considered as the major regulator of ...anti-oxidative defence system.
The aim of this research was to study the effect of supplementation with n-3 PUFAs on the antioxidant status and the gene expression of Nrf2 and Sestrin2 (Sesn2) in patients with type 2 diabetes mellitus (T2DM).
Sixty patients with T2DM were enrolled in a placebo-controlled, double-blind, randomised clinical trial.
The participants were randomly allocated to two intervention groups receiving either n-3 PUFAs (2,700 mg/day) (n = 30) or placebo soft gels containing 900 mg of edible paraffin (n = 30). The main outcome measures were the expression of Sesn2 and Nrf2 genes which were assessed in peripheral blood mononuclear cells (PBMCs) after RNA extraction and cDNA synthesis by real-time PCR. Total antioxidant status in plasma samples was also measured based on the ferric reducing ability of plasma.
NRF2 gene expression was significantly increased in n-3 PUFA-supplemented subjects, compared with the placebo group. Plasma total antioxidant status was also significantly augmented in n-3 PUFA-supplemented subjects. SESN2 gene expression was not significantly affected by n-3 PUFA supplementation although a slight up-regulation was observed.
Supplementation with n-3 PUFAs enhanced NRF2 gene expression and improved overall antioxidant capacity and thus might be considered beneficial in the amelioration of oxidative stress and prevention of T2DM complications.
Trial registration: IRCT20150926024198N4.
Abstract
Background: Visfatin, also known as nicotinamide phosphoribosyltransferase, is an adipokine that has been implicated in obesity, insulin resistance (IR) and diabetes mellitus. Since obesity ...profoundly affects serum lipids, insulin, and glucose metabolism, the aim of this study was to evaluate the relationships between visfatin and metabolic parameters in childhood obesity. Methods: A total of 73 Iranian children and adolescents (31 controls; 42 obese), between the ages of 7 and 16 years, were selected and clinically evaluated. Serum visfatin, leptin, insulin and adiponectin were measured using ELISA, and insulin resistance was calculated by the Homeostasis Model of Assessment of Insulin Resistance (HOMA-IR). Fasting plasma glucose (FPG), triglyceride (TG), total cholesterol (TC), LDL-C and HDL-C were also measured. Metabolic syndrome (MetS) was determined according to IDF criteria. Results: Obese subjects presented significantly higher levels of insulin, LDL-C, HOMA-IR, and leptin and lower levels of adiponectin. Serum Visfatin was higher in obese children than in the control children, and it was significantly higher in obese children with MetS or IR, compared with obese children without MetS or IR. Visfatin levels showed positive correlations with FPG, insulin, and HOMA-IR, in obese subjects and a negative correlation with adiponectin, but no correlation with leptin. Adiponectin levels were correlated with HDL-C and Insulin levels in obese subjects. Leptin levels were correlated with Body mass index (BMI) but not with metabolic parameters. Conclusions: Visfatin is increased in obese children and adolescents, and has a more prominent association with IR and MetS parameters, compared with leptin and adiponectin.
Adipocytes are surrounded by a three-dimensional network of extracellular matrix (ECM) proteins. Aberrant ECM accumulation and remodeling leads to adipose tissue fibrosis. Visfatin is one of the ...adipocytokines that is increased in obesity and is implicated in insulin resistance. The objective of this study was to investigate the effect of visfatin on major components of ECM remodeling. In this study, plasma levels of both endotrophin and visfatin in obese children and adolescents were significantly higher than those in control subjects and they showed a positive correlation with each other. Treatment of 3T3-L1 pre-adipocytes with visfatin caused significant up-regulation of Osteopontin (Opn), Collagen type VI (Col6), matrix metalloproteinases MMP-2 and MMP-9. By using inhibitors of major signaling pathways it was shown that visfatin exerted its effect on Col6a3 gene expression through PI3K, JNK, and NF-кB pathways, while induced Opn gene expression via PI3K, JNK, MAPK/ERK, and NOTCH1. Our conclusion is that, the relationship between visfatin, endotrophin and insulin resistance parameters in obesity as well as increased expression of ECM proteins by visfatin suggests adipose tissue fibrosis as a mechanism for devastating effects of visfatin in obesity.
Abstract
The vast amount of available sequencing data allows the scientific community to explore different genetic alterations that may drive cancer or favor cancer progression. Software developers ...have proposed a myriad of predictive tools, allowing researchers and clinicians to compare and prioritize driver genes and mutations and their relative pathogenicity. However, there is little consensus on the computational approach or a golden standard for comparison. Hence, benchmarking the different tools depends highly on the input data, indicating that overfitting is still a massive problem. One of the solutions is to limit the scope and usage of specific tools. However, such limitations force researchers to walk on a tightrope between creating and using high-quality tools for a specific purpose and describing the complex alterations driving cancer. While the knowledge of cancer development increases daily, many bioinformatic pipelines rely on single nucleotide variants or alterations in a vacuum without accounting for cellular compartments, mutational burden or disease progression. Even within bioinformatics and computational cancer biology, the research fields work in silos, risking overlooking potential synergies or breakthroughs. Here, we provide an overview of databases and datasets for building or testing predictive cancer driver tools. Furthermore, we introduce predictive tools for driver genes, driver mutations, and the impact of these based on structural analysis. Additionally, we suggest and recommend directions in the field to avoid silo-research, moving towards integrative frameworks.
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