DNA methylation and gene expression analysis in adipose tissue to identify new loci associated with T2D development in obesity

Slit3 Fragments Orchestrate Neurovascular Expansion and Thermogenesis in Brown Adipose Tissue

Brown adipose tissue (BAT) represents an evolutionary innovation enabling placental mammals to regulate body temperature through adaptive thermogenesis. Brown adipocytes are surrounded by a dense network of blood vessels and sympathetic nerves that support their development and thermogenic function. Cold exposure stimulates BAT thermogenesis through the coordinated induction of brown adipogenesis, angiogenesis, and sympathetic innervation. However, how these distinct processes are coordinated remains unclear. Here, we identify Slit guidance ligand 3 (Slit3) as a new niche factor that mediates the crosstalk among adipocyte progenitors, endothelial cells, and sympathetic nerves. We show that adipocyte progenitors secrete Slit3 which regulates both angiogenesis and sympathetic innervation in BAT and is essential for BAT thermogenesis in vivo. Proteolytic cleavage of Slit3 generates secreted Slit3-N and Slit3-C fragments, which activate distinct receptors to stimulate angiogenesis and sympathetic innervation, respectively. Moreover, we introduce bone morphogenetic protein-1 (Bmp1) as the first Slit protease identified in vertebrates. In summary, this study underscores the essential role of Slit3-mediated neurovascular network expansion in enabling cold-induced BAT adaptation. The co-regulation of neurovascular expansion by Slit3 fragments provides a bifurcated yet harmonized approach to ensure a synchronized response of BAT to environmental challenges. This study presents the first evidence that adipocyte progenitors regulate tissue innervation, revealing a previously unrecognized dimension of cellular interaction within adipose tissue.

Identification of Schizophrenia Susceptibility Loci in the Urban Taiwanese Population

Background and Objectives: Genomic studies have identified several SNP loci associated with schizophrenia in East Asian populations. Environmental factors, particularly urbanization, play a significant role in schizophrenia development. This study aimed to identify schizophrenia susceptibility loci and characterize their biological functions and molecular pathways in Taiwanese urban Han individuals. Materials and Methods: Participants with schizophrenia were recruited from the Taiwan Precision Medicine Initiative at Tri-Service General Hospital. Genotype-phenotype association analysis was performed, with significant variants annotated and analyzed for functional relevance. Results: A total of 137 schizophrenia patients and 26,129 controls were enrolled. Ten significant variants (p < 1 × 10-5) and 15 expressed genes were identified, including rs1010840 (SOWAHC and RGPD6), rs11083963 (TRPM4), rs11619878 (LINC00355 and LINC01052), rs117010638 (AGBL1 and MIR548AP), rs1170702 (LINC01680 and LINC01720), rs12028521 (KAZN and PRDM2), rs12859097 (DMD), rs1556812 (ATP11A), rs78144262 (LINC00977), and rs9997349 (ENPEP). These variants and associated genes are involved in immune response, blood pressure regulation, muscle function, and the cytoskeleton. Conclusions: Identified variants and associated genes suggest a potential genetic predisposition to schizophrenia in the Taiwanese urban Han population, highlighting the importance of potential comorbidities, considering population-specific genetic and environmental interactions.

Epigenetic and Molecular Alterations in Obesity: Linking CRP and DNA Methylation to Systemic Inflammation

Obesity is marked by excessive fat accumulation in the adipose tissue, which disrupts metabolic processes and causes chronic systemic inflammation. Commonly, body mass index (BMI) is used to assess obesity-related risks, predicting potential metabolic disorders. However, for a better clustering of obese patients, we must consider molecular and epigenetic changes which may be responsible for inflammation and metabolic changes. Our study involved two groups of patients, obese and healthy donors, on which routine analysis were performed, focused on BMI, leukocytes count, and C-reactive protein (CRP) and completed with global DNA methylation and gene expression analysis for genes involved in inflammation and adipogenesis. Our results indicate that obese patients exhibited elevated leukocytes levels, along with increased BMI and CRP. The obese group revealed a global hypomethylation and upregulation of proinflammatory genes, with adipogenesis genes following the same trend of being overexpressed. The study confirms that obesity is linked to systematic inflammation and metabolic dysfunction through epigenetic and molecular alterations. The CRP was correlated with the hypomethylation status in obese patients, and this fact may contribute to a better understanding of the roles of specific genes in adipogenesis and inflammation, leading to a better personalized therapy.

The Apo gene's genetic variants: hidden role in Asian vascular risk

Vascular risk factors, including diabetes, hypertension, hyperlipidemia, and obesity, pose significant health threats with implications extending to neuropsychiatric disorders such as stroke and Alzheimer's disease. The Asian population, in particular, appears to be disproportionately affected due to unique genetic predispositions, as well as epigenetic factors such as dietary patterns and lifestyle habits. Existing management strategies often fall short of addressing these specific needs, leading to greater challenges in prevention and treatment. This review highlights a significant gap in our understanding of the impact of genetic screening in the early detection and tailored treatment of vascular risk factors among the Asian population. Apolipoprotein, a key player in cholesterol metabolism, is primarily associated with dyslipidemia, yet emerging evidence suggests its involvement in conditions such as diabetes, hypertension, and obesity. While genetic variants of vascular risk are ethnic-dependent, current evidence indicates that epigenetics also exhibits ethnic specificity. Understanding the interplay between Apolipoprotein and genetics, particularly within diverse ethnic backgrounds, has the potential to refine risk stratification and enhance precision in management. For Caucasian carrying the APOA5 rs662799 C variant, pharmacological interventions are recommended, as dietary interventions may not be sufficient. In contrast, for Asian populations with the same genetic variant, dietary modifications are initially advised. Should dyslipidemia persist, the consideration of pharmaceutical agents such as statins is recommended.

Plasticity of Adipose Tissues: Interconversion among White, Brown, and Beige Fat and Its Role in Energy Homeostasis

Obesity, characterized by the excessive accumulation of adipose tissue, has emerged as a major public health concern worldwide. To develop effective strategies for treating obesity, it is essential to comprehend the biological properties of different adipose tissue types and their respective roles in maintaining energy balance. Adipose tissue serves as a crucial organ for energy storage and metabolism in the human body, with functions extending beyond simple fat storage to encompass the regulation of energy homeostasis and the secretion of endocrine factors. This review provides an overview of the key characteristics, functional differences, and interconversion processes among white adipose tissue (WAT), brown adipose tissue (BAT), and beige adipose tissue. Moreover, it delves into the molecular mechanisms and recent research advancements concerning the browning of WAT, activation of BAT, and whitening of BAT. Although targeting adipose tissue metabolism holds promise as a potential approach for obesity treatment, further investigations are necessary to unravel the intricate biological features of various adipose tissue types and elucidate the molecular pathways governing their interconversion. Such research endeavors will pave the way for the development of more efficient and targeted therapeutic interventions in the fight against obesity.

EH domain-containing protein 2 (EHD2): Overview, biological function, and therapeutic potential

EH domain-containing protein 2 (EHD2) is a member of the EHD protein family and is mainly located in the plasma membrane, but can also be found in the cytoplasm and endosomes. EHD2 is also a nuclear-cytoplasmic shuttle protein. After entering the cell nuclear, EHD2 acts as a corepressor of transcription to inhibit gene transcription. EHD2 regulates a series of biological processes. As a key regulator of endocytic transport, EHD2 is involved in the formation and maintenance of endosomal tubules and vesicles, which are critical for the intracellular transport of proteins and other substances. The N-terminal of EHD2 is attached to the cell membrane, while its C-terminal binds to the actin-binding protein. After binding, EHD2 connects with the actin cytoskeleton, forming the curvature of the membrane and promoting cell endocytosis. EHD2 is also associated with membrane protein trafficking and receptor signaling, as well as in glucose metabolism and lipid metabolism. In this review, we highlight the recent advances in the function of EHD2 in various cellular processes and its potential implications in human diseases such as cancer and metabolic disease. We also discussed the prospects for the future of EHD2. EHD2 has a broad prospect as a therapeutic target for a variety of diseases. Further research is needed to explore its mechanism, which could pave the way for the development of targeted treatments.

Epigenetic modifications in obesity-associated diseases

The global prevalence of obesity has reached epidemic levels, significantly elevating the susceptibility to various cardiometabolic conditions and certain types of cancer. In addition to causing metabolic abnormalities such as insulin resistance (IR), elevated blood glucose and lipids, and ectopic fat deposition, obesity can also damage pancreatic islet cells, endothelial cells, and cardiomyocytes through chronic inflammation, and even promote the development of a microenvironment conducive to cancer initiation. Improper dietary habits and lack of physical exercise are important behavioral factors that increase the risk of obesity, which can affect gene expression through epigenetic modifications. Epigenetic alterations can occur in early stage of obesity, some of which are reversible, while others persist over time and lead to obesity-related complications. Therefore, the dynamic adjustability of epigenetic modifications can be leveraged to reverse the development of obesity-associated diseases through behavioral interventions, drugs, and bariatric surgery. This review provides a comprehensive summary of the impact of epigenetic regulation on the initiation and development of obesity-associated cancers, type 2 diabetes, and cardiovascular diseases, establishing a theoretical basis for prevention, diagnosis, and treatment of these conditions.

Maackiain Mimics Caloric Restriction through aak-2-Mediated Lipid Reduction in Caenorhabditis elegans

Obesity prevalence is becoming a serious global health and economic issue and is a major risk factor for concomitant diseases that worsen the quality and duration of life. Therefore, the urgency of the development of novel therapies is of a particular importance. A previous study of ours revealed that the natural pterocarpan, maackiain (MACK), significantly inhibits adipogenic differentiation in human adipocytes through a peroxisome proliferator-activated receptor gamma (PPARγ)-dependent mechanism. Considering the observed anti-adipogenic potential of MACK, we aimed to further elucidate the molecular mechanisms that drive its biological activity in a Caenorhabditis elegans obesity model. Therefore, in the current study, the anti-obesogenic effect of MACK (25, 50, and 100 μM) was compared to orlistat (ORST, 12 μM) as a reference drug. Additionally, the hybrid combination between the ORST (12 μM) and MACK (100 μM) was assessed for suspected synergistic interaction. Mechanistically, the observed anti-obesogenic effect of MACK was mediated through the upregulation of the key metabolic regulators, namely, the nuclear hormone receptor 49 (nhr-49) that is a functional homologue of the mammalian PPARs and the AMP-activated protein kinase (aak-2/AMPK) in C. elegans. Collectively, our investigation indicates that MACK has the potential to limit lipid accumulation and control obesity that deserves future developments.

Applicability of mesenchymal stem cell-derived exosomes as a cell-free miRNA therapy and epigenetic modifiers for diabetes

Given that exosome nanovesicles constitute various growth factors, miRNAs and lncRNAs, they have implications for epigenetic modifications. Few studies have shown that exosomes from mesenchymal stem cells (MSCs) exhibit therapeutic effects on diabetic complications by substituting miRNAs and regulating histone modifications. Therefore, reversing epigenetic aberrations in diabetes may provide new insight into its treatment. This review discusses the impact of DNA and histone methylations on the development of diabetes and its complications. Further, we talk about miRNAs dysregulated in diabetic conditions and the possibility of utilizing mesenchymal stem cell (MSC) exosomes for the development of miRNA cell-free therapy and epigenetic modifiers in reversing diabetic-induced epigenetic alterations.

Associations between Host Genetic Variants and Subgingival Microbiota in Patients with the Metabolic Syndrome

Host genetic variants may affect oral biofilms, playing a role in the periodontitis-systemic disease axis. This is the first study to assess the associations between host genetic variants and subgingival microbiota in patients with metabolic syndrome (MetS); 103 patients with MetS underwent medical and periodontal examinations and had blood and subgingival plaque samples taken. DNA was extracted and processed, assessing a panel of selected single nucleotide polymorphisms (SNPs) first (hypothesis testing) and then expanding to a discovery phase. The subgingival plaque microbiome from these patients was profiled. Analysis of associations between host genetic and microbial factors was performed and stratified for periodontal diagnosis. Specific SNPs within RUNX2, CAMTA1 and VDR genes were associated with diversity metrics with no genome-wide associations detected for periodontitis severity or Mets components at p < 10-7. Severe periodontitis was associated with pathogenic genera and species. Some SNPs correlated with specific bacterial genera as well as with microbial taxa, notably VDR (rs12717991) with Streptococcus mutans and RUNX2 (rs3749863) with Porphyromonas gingivalis. In conclusion, variation in host genotypes may play a role in the dysregulated immune responses characterizing periodontitis and thus the oral microbiome, suggesting that systemic health-associated host traits further interact with oral health and the microbiome.

Precision Medicine in Type 2 Diabetes Mellitus: Utility and Limitations

Type 2 diabetes mellitus (T2DM) is one of the most widespread diseases in Western countries, and its incidence is constantly increasing. Epidemiological studies have shown that in the next 20 years. The number of subjects affected by T2DM will double. In recent years, owing to the development and improvement in methods for studying the genome, several authors have evaluated the association between monogenic or polygenic genetic alterations and the development of metabolic diseases and complications. In addition, sedentary lifestyle and socio-economic and pandemic factors have a great impact on the habits of the population and have significantly contributed to the increase in the incidence of metabolic disorders, obesity, T2DM, metabolic syndrome, and liver steatosis. Moreover, patients with type 2 diabetes appear to respond to antihyperglycemic drugs. Only a minority of patients could be considered true non-responders. Thus, it appears clear that the main aim of precision medicine in T2DM is to identify patients who can benefit most from a specific drug class more than from the others. Precision medicine is a discipline that evaluates the applicability of genetic, lifestyle, and environmental factors to disease development. In particular, it evaluated whether these factors could affect the development of diseases and their complications, response to diet, lifestyle, and use of drugs. Thus, the objective is to find prevention models aimed at reducing the incidence of pathology and mortality and therapeutic personalized approaches, to obtain a greater probability of response and efficacy. This review aims to evaluate the applicability of precision medicine for T2DM, a healthcare burden in many countries.

DNA Methylation Remodeling after Bariatric Surgery Correlates with Clinical Parameters

The altered functions of adipose tissue are one of the main issues in obesity. Bariatric surgery is associated with improvement of obesity associated comorbidities. Here DNA methylation remodeling in adipose tissue after bariatric surgery is examined. After six months postoperative, DNA methylation shows changes in 1155 CpG sites, 66 of these sites correlate with body mass index. Some sites also show correlation with LDL-C, HDL-C, total cholesterol, and triglycerides. CpG sites are located in genes that have not previously been linked to obesity or metabolic diseases. GNAS complex locus is one of those that presented CpG site with the greatest changes after surgery, and the most significant correlation with BMI and lipid profiles. These results show that epigenetic regulation may be involved in the alteration of adipose tissue functions in obesity.

Novel Differentially Methylated Regions Identified by Genome-Wide DNA Methylation Analyses Contribute to Racial Disparities in Childhood Obesity

The magnitude of the childhood obesity epidemic and its effects on public health has accelerated the pursuit of practical preventative measures. Epigenetics is one subject that holds a lot of promise, despite being relatively new. The study of potentially heritable variations in gene expression that do not require modifications to the underlying DNA sequence is known as epigenetics. Here, we used Illumina MethylationEPIC BeadChip Array to identify differentially methylated regions in DNA isolated from saliva between normal weight (NW) and overweight/obese (OW/OB) children and between European American (EA) and African American (AA) children. A total of 3133 target IDs (associated with 2313 genes) were differentially methylated (p < 0.05) between NW and OW/OB children. In OW/OB children, 792 target IDs were hypermethylated and 2341 were hypomethylated compared to NW. Similarly, in the racial groups EA and AA, a total of 1239 target IDs corresponding to 739 genes were significantly differentially methylated in which 643 target IDs were hypermethylated and 596 were hypomethylated in the AA compared to EA participants. Along with this, the study identified novel genes that could contribute to the epigenetic regulation of childhood obesity.