Clozapine is the most effective second-generation antipsychotic drug, especially for the therapy of treatment-resistant schizophrenia. However, it is associated with metabolic side-effects. Clozapine has a high antagonistic affinity to muscarinic M3 receptors, which has been reported to play a significant role in these side-effects. This study aimed to investigate whether co-administration of cevimeline (an M3 receptor agonist) could prevent the metabolic disorders induced by clozapine. Female Sprague Dawley rats were treated orally with clozapine (20 mg/kg, 3 times daily) and/or cevimeline at three dosages (3, 6, 9 mg/kg, 3 times daily), or a vehicle for two weeks. Body weight gain, food/water intake, and temperature were recorded. Open field tests were performed to assess motor activity. Clozapine only treatment significantly decreased body weight gain, feeding efficiency, perirenal, periovary, inguinal, total white fat mass, and NEFA levels. The reduction in body weight gain and feeding efficiency caused by clozapine was partially reversed by co-treatment with 3 or 6 mg/kg cevimeline. Clozapine also significantly increased the liver mass, LDL, and HDL level, which were reversed by the co-treatment with cevimeline at all tested dosages. These results support further clinical trials to evaluate cevimeline's potential in controlling clozapine-induced dyslipidemia.

Bovine viral diarrhea virus (BVDV) is the most detrimental pestivirus within the cattle industry. Infection with vertically transmissible BVDV prior to 125 days of gestation results in the generation of a persistently infected (PI) calf. These PI calves are unable to clear the virus in utero, due to an incomplete immune response. However, when infection with BVDV occurs after 150 days of gestation, the fetus clears the transient infection (TI) in utero and is born with antibodies specific to the infecting strain of BVDV. Variations in DNA methylation have been identified in white blood cells (WBC) from TI heifers at birth. It was hypothesized that epigenomic alterations persist into the postnatal period and contribute to previously undocumented pathologies. To study these possible effects, DNA was isolated from the WBCs of 5 TI heifers and 5 control heifers at 4 months of age and subjected to reduced representation bisulfite sequencing (RRBS).

Differential analysis of the methylome revealed a total of 3,047 differentially methylated CpG sites (DMSs), 1,349 of which were hypermethylated and the other 1,698 were hypomethylated. Genes containing differential methylation were associated with inflammation, reactive oxygen species (ROS) production, and metabolism. Complete blood count (CBC) data identified a higher lymphocyte percentage in TI heifers. When compared in the context of the CD45+ parent population, spectral flow cytometry revealed increased intermediate monocytes, B cells, and CD25+/CD127- T cells, and decreased CD4+/CD8b+ T cells. Comparative analysis revealed differential methylation of CpG sites contained in 205 genes, 5 promoters, and 10 CpG islands at birth that were also present at 4 months of age. Comparison of differential methylation in TI heifers and PI heifers at 4 months of age showed 465 genes, 18 promoters, and 34 CpG islands in common.

Differential methylation of WBC DNA persists to 4 months of age in TI heifers and is associated with dysregulation of inflammation, metabolism, and growth. Analysis of differential methylation in TI heifers contributes to the understanding of how fetal infection with BVDV induces postnatal detriments related to profit loss.

Brown adipose tissue (BAT) is the main site of non-shivering thermogenesis (NST) in small mammals, playing an important role in maintaining body temperature and energy balance. Huddling is a behavioral strategy for small rodents to save energy and improve the survival under cold environments. However, the way of huddling behavior influence on hypothalamus, which regulate BAT thermogenesis in small mammals is rarely illustrated. We used male Brandt's voles (Lasiopodomys brandtii) to explore the possible regulation mechanisms in BAT thermogenesis by the way of cold acclimation and huddling behavior.

There is a strong relationship between huddling behavior and NST in BAT. The hypothalamus, which is impacted by huddling behavior, influences PPAR signaling pathway in the BAT, and induces thermogenesis through Calcium signaling pathway. PPAR pathway causes crosstalk among NF-κB signaling pathway, Thermogenesis and Fatty acid metabolism to perform functions for thermogenesis.

The results suggest that huddling behavior can modulate adaptive thermogenesis in BAT. Cold acclimation and huddling had a synergistic effect on the regulation of thermogenic function, the hypothalamus mediates thermogenic changes in BAT induced by huddling behavior. In BAT, the specific pathway of thermogenesis is as follows: TRAF6-PPARγ-UCP1-SUCLG1.

Cold exposure is a regulatory biological functions in animals. The interaction of thermogenesis and energy metabolism in brown adipose tissue (BAT) is important for metabolic regulation in cold stress. Brown adipocytes (BAs) produce uncoupling protein 1 (UCP1) in mitochondria, activating non-shivering thermogenesis (NST) by uncoupling fuel combustion from ATP production in response to cold stimuli. To elucidate the mechanisms underlying thermogenesis and energy metabolism in BAT under cold stress, we explored how cold exposure triggers the activation of BAT thermogenesis and regulates overall energy metabolism. First, we briefly outline the precursor composition and function of BA. Second, we explore the roles of the cAMP- protein kinase A (PKA) and adenosine monophosphate-activated protein kinase (AMPK) signaling pathways in thermogenesis and energy metabolism in BA during cold stress. Then, we analyze the mechanism by which BA regulates mitochondria homeostasis and energy balance during cold stress. This research reveals potential therapeutic targets, such as PKA, AMPK, UCP1 and PGC-1α, which can be used to develop innovative strategies for treating metabolic diseases. Furthermore, it provides theoretical support for optimizing cold stress response strategies, including the pharmacological activation of BAT and the genetic modulation of thermogenic pathways, to improve energy homeostasis in livestock.

The widespread use of wireless technologies has raised public health concerns about the biological effects of radiofrequency (RF) exposure. Children have a higher specific absorption rate (SAR) of radiation energy compared to adults. Furthermore, brown adipose tissue (BAT) is more prevalent in infants and tends to decrease with age. Previous animal studies demonstrated a cold sensation in rats exposed to 900 MHz (second generation, 2G). UCP1-dependent thermogenesis and BAT hyperplasia are two fundamental adaptive mechanisms initiated in response to cold. This study investigated the impact of short-term exposure to 2G and fifth generation (5G) on key thermogenic and adipogenic markers related to these mechanisms while considering age and exposure duration. Juvenile and young adult Wistar rats were randomized into three subgroups: a 5G group (3.5 GHz), 2G group (900 MHz), and a control group (SHAM). They were exposed to their respective continuous-wave RF signals for 1 or 2 weeks at an intensity of 1.5 V/m, with two exposure sessions of 1 h per day. After the exposure period, a RT-qPCR was carried out to evaluate the genetic markers involved in BAT thermogenesis and adipogenesis. Two adipogenic biomarkers were affected; a fold change reduction of 49% and 32% was detected for PRDM16 (p = 0.016) and C/EBP β (p = 0.0002), respectively, after 5G exposure, regardless of age and exposure duration. No significant RF effect was found on UCP1-dependent thermogenesis at a transcriptional level. These findings suggest that exposure to a 5G radiofrequency may partially disrupt brown adipocyte differentiation and thermogenic function by downregulating PRDM16 and C/EBP β, possibly leading to higher cold sensitivity.

Tumors exhibit an increased ability to obtain and metabolize nutrients. Here, we implant engineered adipocytes that outcompete tumors for nutrients and show that they can substantially reduce cancer progression, a technology termed adipose manipulation transplantation (AMT). Adipocytes engineered to use increased amounts of glucose and fatty acids by upregulating UCP1 were placed alongside cancer cells or xenografts, leading to significant cancer suppression. Transplanting modulated adipose organoids in pancreatic or breast cancer genetic mouse models suppressed their growth and decreased angiogenesis and hypoxia. Co-culturing patient-derived engineered adipocytes with tumor organoids from dissected human breast cancers significantly suppressed cancer progression and proliferation. In addition, cancer growth was impaired by inducing engineered adipose organoids to outcompete tumors using tetracycline or placing them in an integrated cell-scaffold delivery platform and implanting them next to the tumor. Finally, we show that upregulating UPP1 in adipose organoids can outcompete a uridine-dependent pancreatic ductal adenocarcinoma for uridine and suppress its growth, demonstrating the potential customization of AMT.

To investigate the effect of pachymic acid on brown/beige adipocyte differentiation and lipid metabolism in preadipocytes 3T3-L1 MBX.

The brown cocktail method was employed to induce 3T3-L1 MBX cells to differentiate into beige adipocytes. The impact of pachymic acid on the viability of 3T3-L1 MBX preadipocytes was evaluated using the CCK-8 assay. The formation of lipid droplets following treatment with pachymic acid was observed through oil red O staining, and the content of lipids in differentiated cells was determined. The expression levels of key browning genes, including uncoupling protein (Ucp) 1, the peroxisome proliferation-activating receptor gamma coactivator (Pgc)-1α, and the transcription factor containing PR domain 16 (Prdm16) were detected by quantitative reverse transcription polymerase chain reaction. The expression of sterol regulatory element binding protein (Srebp) 1c, acetyl-CoA carboxylase (Acc), fatty acid synthetase (Fas), and steroid-sensitive lipase (Hsl), fatty triglyceride hydrolase (Atgl), and carnitine palmitoyl transferase (Cpt) 1 of lipolysis-related genes were also examined.

The 3T3-L1 MBX was induced in vitro to form beige adipocytes with high expression of key browning genes, including Ucp1, Pgc-1α, Prdm16, and beige adipose-marker genes, including Cd137, Tbx1, and Tmem26. The concentration range of 0-80 μM pachymic acid was non-cytotoxic to 3T3-L1 MBX. Pachymic acid treatment significantly inhibited the differentiation of 3T3-L1 MBX, resulting in a notable decrease in lipid accumulation content (P<0.01). Additionally, there was a marked increase in the expression of key browning genes and their proteins, such as Ucp1, Pgc-1α, and Prdm16, while the expressions of fat synthesis-related genes Srebp1c, Acc and Fas were significantly decreased (all P<0.05). The expressions of lipolysis-related genes, including Hsl, Atgl, and Cpt1, were significantly increased (all P<0.05). Besides, treating with 20 μmol/L pachymic acid showed the most pronounced effect.

Pachymic acid can inhibit fat synthesis and promote lipid decomposition by regulating the brown formation and lipid differentiation of 3T3-L1 MBX preadipocytes.

Nano-plastics (NPs) have emerged as a significant environmental pollutant, widely existing in water environment, and pose a serious threat to health and safety with the intake of animals. Skeletal muscle, a vital organ for complex life activities and functional demands, has received limited attention regarding the effects of NPs. In this study, the effects of polystyrene NPs (PS-NPs) on skeletal muscle development were studied by oral administration of different sizes (1 mg/kg) of PS-NPs in mice. The findings revealed that PS-NPs resulted in skeletal muscle damage and significantly hindered muscle differentiation, exhibiting an inverse correlation with PS-NPs particle size. Morphological analysis demonstrated PS-NPs caused partial disruption of muscle fibers, increased spacing between fibers, and lipid accumulation. RT-qPCR and western blots analyses indicated that PS-NPs exposure downregulated the expression of myogenic differentiation-related factors (Myod, Myog and Myh2), activated PPARγ/LXRβ pathway, and upregulated the expressions of lipid differentiation-related factors (SREBP1C, SCD-1, FAS, ACC1, CD36/FAT, ADIPOQ, C/EBPα and UCP-1). In vitro experiments, C2C12 cells were used to confirm cellular penetration of PS-NPs (0, 100, 200, 400 μg/mL) through cell membranes along with activation of PPARγ expression. Furthermore, to verify LXRβ as a key signaling molecule, silencing RNA transfection experiments were conducted, resulting in no increase in the expressions of PPARγ, LXRβ, SREBP1C, FAS, CD36/FAT, ADIPOQ, C/EBPα and UCP-1 even after exposure to PS-NPs. However, the expressions of SCD-1and ACC1 remained unaffected. The present study evidenced that exposure to PS-NPs induced lipid accumulation via the PPARγ/LXRβ pathway thereby influencing skeletal muscle development.

Sirtuin 5 (SIRT5) plays an important role in the maintenance of lipid metabolism and in white adipose tissue browning. In this study, we established a mouse model for diet-induced obesity and the browning of white fat; combined with gene expression intervention, transcriptome sequencing, and cell molecular biology methods, the regulation and molecular mechanisms of SIRT5 on fat deposition and beige fat formation were studied. The results showed that the loss of SIRT5 in obese mice exacerbated white adipose tissue deposition and metabolic inflexibility. Furthermore, the deletion of SIRT5 in a white-fat-browning mouse increased the succinylation of uncoupling protein 1 (UCP1), resulting in a loss of the beiging capacity of the subcutaneous white adipose tissue and impaired cold tolerance. Mechanistically, the inhibition of SIRT5 results in impaired CCAAT/enhancer binding protein beta (C/EBPβ) expression in brown adipocytes, which in turn reduces the UCP1 transcriptional pathway. Thus, the transcription of UCP1 mediated by the SIRT5-C/EBPβ axis is critical in regulating energy balance and obesity-related metabolism.

Obesity is increasing globally and is closely associated with a range of metabolic disorders, including metabolic associated fatty liver disease, diabetes, and cardiovascular diseases. An effective strategy to combat obesity involves stimulating brown and beige adipocyte thermogenesis, which significantly enhances energy expenditure. Recent research has underscored the vital role of PRDM16 in the development and functionality of thermogenic adipocytes. Consequently, PRDM16 has been identified as a potential therapeutic target for obesity and its related metabolic disorders. This review comprehensively examines various studies that focus on combating obesity by directly targeting PRDM16 in adipose tissue.

Testosterone (T) therapy increases lean mass and reduces total body and truncal fat mass in hypogonadal men. However, the underlying molecular mechanisms for the reciprocal changes in fat and lean mass in humans are not entirely clear.

Secondary analysis of specimens obtained from a single-arm, open-label clinical trial on pharmacogenetics of response to T therapy in men with late-onset hypogonadism, conducted between 2011 and 2016 involving 105 men (40-74 years old), who were given intramuscular T cypionate 200 mg every 2 weeks for 18 months. Subcutaneous fat (SCF), peripheral blood mononuclear cells (PBMC) and serum were obtained from the participants at different time points of the study. We measured transcription factors for adipogenesis and myogenesis in the SCF, and PBMC, respectively, by real-time quantitative PCR at baseline and 6 months. Serum levels of FOLLISTATIN, PAX7, MYOSTATIN, ADIPSIN, and PRDM16 were measured by ELISA.

As expected, there was a significant increase in T and estradiol levels after 6 months of T therapy. There was also a reduction in fat mass and an increase in lean mass after 6 months of T therapy. Gene-protein studies showed a significant reduction in the expression of the adipogenic markers PPARγ in SCF and ADIPSIN levels in the serum, together with a concomitant significant increase in the expression of myogenic markers, MYOD in PBMC and PAX7 and FOLLISTATIN levels in the serum after 6 months of T therapy compared to baseline. Interestingly, there was a significant increase in the adipo-myogenic switch, PRDM16, expression in SCF and PBMC, and in circulating protein levels in the serum after 6 months of T therapy, which is likely from increased estradiol.

Our study supports that molecular shift from the adipogenic to the myogenic pathway in men with hypogonadism treated with T could be mediated directly or indirectly by enhanced PRDM16 activity, in turn a result from increased estradiol level. This might have led to the reduction in body fat and increase in lean mass commonly seen in hypogonadal men treated with T.

Existing delivery methods for RNAi therapeutics encounter challenges, including stability, specificity, and off-target effects, which restrict their clinical effectiveness. In this study, a novel miR-133a zipper nanoparticle (NP) system that integrates miRNA zipper technology with rolling circle transcription (RCT) to achieve targeted delivery and specific regulation of miR-133a in adipocytes, is presented. This innovative approach can greatly enhance the delivery and release of miR-133a zippers, increasing the expression of thermogenic genes and mitochondrial biogenesis. he miR-133a zipper NP is utilized for the delivery of miRNA zipper-blocking miR-133a, an endogenous inhibitor of Prdm16 expression, to enhance the thermogenic activity of adipocytes by modulating their transcriptional program. Inhibition of miR-133a through the miR-133a zipper NP leads to more significant upregulation of thermogenic gene expression (Prdm16 and Ucp1) than with the free miR-133a zipper strand. Furthermore, miR-133a zipper NPs increase the number of mitochondria and induce heat production, reducing the size of 3D adipose spheroids. In short, this study emphasizes the role of RNA NPs in improving RNAi stability and specificity and paves the way for broader applications in gene therapy. Moreover, this research represents a significant advancement in RNAi-based treatments, pointing toward a promising direction for future therapeutic strategies.

Extensive research has shown that PR domain 16 (PRDM16) plays a critical role in adipose tissue metabolism, including processes such as browning and thermogenesis of adipocytes, beigeing of adipocytes, and adipogenic differentiation of myoblasts. These functions have been associated with diseases such as obesity and diabetes. Additionally, PRDM16 has been correlated with various other conditions, including migraines, heterochromatin abnormalities, metabolic syndrome, cardiomyopathy, sarcopenia, nonsyndromic cleft lip, and essential hypertension, among others. However, there is currently no systematic or comprehensive conclusion regarding the mechanism of PRDM16 in human tumours, including haematologic and solid tumours. The aim of this review is to provide an overview of the research progress on PRDM16 in haematologic and solid tumours by incorporating recent literature findings. Furthermore, we explore the prospects of PRDM16 in the precise diagnosis and treatment of human haematologic and solid tumours.

White adipocytes store energy, while brown and brite adipocytes release heat via nonshivering thermogenesis. In this study, we characterized two murine embryonic clonal preadipocyte lines, EB5 and EB7, each displaying unique gene marker expression profiles. EB5 cells differentiate into brown adipocytes, whereas EB7 cells into brite (also known as beige) adipocytes. To draw a comprehensive comparison, we contrasted the gene expression patterns, adipogenic capacity, as well as carbohydrate and lipid metabolism of these cells to that of F442A, a well-known white preadipocyte and adipocyte model. We found that commitment to differentiation in both EB5 and EB7 cells can be induced by 3-Isobutyl-1-methylxanthine/dexamethasone (Mix/Dex) and staurosporine/dexamethasone (St/Dex) treatments. Additionally, the administration of rosiglitazone significantly enhances the brown and brite adipocyte phenotypes. Our data also reveal the involvement of a series of genes in the transcriptional cascade guiding adipogenesis, pinpointing GSK3β as a critical regulator for both EB5 and EB7 adipogenesis. In a developmental context, we observe that, akin to brown fat progenitors, brite fat progenitors make their appearance in murine development by 11-12 days of gestation or potentially earlier. This result contributes to our understanding of adipocyte lineage specification during embryonic development. In conclusion, EB5 and EB7 cell lines are valuable for research into adipocyte biology, providing insights into the differentiation and development of brown and beige adipocytes. Furthermore, they could be useful for the characterization of drugs targeting energy balance for the treatment of obesity and metabolic diseases.

Deficiency of the epigenome modulator histone deacetylase 3 (HDAC3) in brown adipose tissue (BAT) impairs the ability of mice to survive in near-freezing temperatures. Here, we report that short-term exposure to mild cold temperature (STEMCT: 15°C for 24 h) averted lethal hypothermia of mice lacking HDAC3 in BAT (HDAC3 BAT KO) exposed to 4°C. STEMCT restored the induction of the thermogenic coactivator PGC-1α along with UCP1 at 22°C, which is greatly impaired in HDAC3-deficient BAT, and deletion of either UCP1 or PGC-1α prevented the protective effect of STEMCT. Remarkably, this protection lasted for up to 7 days. Transcriptional activator C/EBPβ was induced by short-term cold exposure in mouse and human BAT and, uniquely, remained high for 7 days following STEMCT. Adeno-associated virus-mediated knockdown of BAT C/EBPβ in HDAC3 BAT KO mice erased the persistent memory of STEMCT, revealing the existence of a C/EBPβ-dependent and HDAC3-independent cold-adaptive epigenomic memory.

Vascular calcification in diabetes patients is a major independent risk factor for developing diabetic cardiovascular complications. However, the mechanisms by which diabetes leads to vascular calcification are complex and not yet fully understood. Our previous study revealed that miR-32-5p is a potential new diagnostic marker for coronary artery calcification. In this study, we found that miR-32-5p levels were significantly greater in the plasma of type 2 diabetes patients with coronary artery calcification and were positively correlated with the coronary artery calcification score. In type 2 diabetic mice, miR-32-5p levels were also elevated in the aorta, and knockout of miR-32-5p inhibited the osteogenic differentiation of vascular smooth muscle cells in vivo. Furthermore, overexpression of miR-32-5p promoted vascular smooth muscle cell calcification, while antagonism of miR-32-5p inhibited vascular smooth muscle cell calcification under high-glucose conditions. GATA binding protein 6 (GATA6) was identified as the key target gene through which miR-32-5p promotes vascular smooth muscle cell calcification. Overexpression of GATA6 antagonized the effects of miR-32-5p on vascular calcification. Additionally, high glucose levels were shown to induce the upregulation of miR-32-5p by activating CCAAT/enhancer binding protein beta (CEBPB). These results suggest that miR-32-5p is an important procalcification factor in vascular calcification associated with type 2 diabetes and identify the CEBPB/miR-32-5p/GATA6 axis as a potential biomarker and therapeutic target for preventing and treating vascular calcification in type 2 diabetes.

Endothelial cells play an important role in the metabolism of adipose tissue (AT). This study aimed to analyze the changes that adipose tissue in AT endothelial cells undergo during the development of obesity, using single-nucleus RNA sequence (snRNA-seq). Mouse paraepididymal AT cells were subjected to snRNA-seq with the 10X Genomics platform. The cell types were then clustered using t-distributed stochastic neighbor embedding and unbiased computational informatics analyses. Protein-protein interactions network was established using the STRING database and visualized using Cytoscape. The dataset was subjected to differential gene enrichment analysis. In total, 21,333 cells acquired from 24 mouse paraepididymal AT samples were analyzed using snRNA-seq. This study identified 18 distinct clusters and annotated macrophages, fibroblasts, epithelial cells, T cells, endothelial cells, stem cells, neutrophil cells, and neutrophil cell types based on representative markers. Cluster 12 was defined as endothelial cells. The proportion of endothelial cells decreased with the development of obesity. Inflammatory factors, such as Vegfa and Prdm16 were upregulated in the medium obesity group but downregulated in the obesity group. Genes, such as Prox1, Erg, Flt4, Kdr, Flt1, and Pecam1 promoted the proliferation of AT endothelial cells and maintained the internal environment of AT. This study established a reference model and general framework for studying the mechanisms, biomarkers, and therapeutic targets of endothelial cell dysfunction-related diseases at the single-cell level.

Diabetes mellitus is a disorder characterised metabolic dysfunction that results in elevated glucose level in the bloodstream. Diabetes is of two types, type1 and type 2 diabetes. Obesity is considered as one of the major reasons intended for incidence of diabetes hence it turns out to be essential to study about the adipose tissue which is responsible for fat storage in body. Adipose tissues play significant role in maintaining the balance between energy stabilization and homeostasis. The three forms of adipose tissue are - White adipose tissue (WAT), Brown adipose tissue (BAT) and Beige adipose tissue (intermediate form). The amount of BAT gets reduced, and WAT starts to increase with the age. WAT when exposed to certain stimuli gets converted to BAT by the help of certain transcriptional regulators. The browning of WAT has been a matter of study to treat the metabolic disorders and to initiate the expenditure of energy. The three main regulators responsible for the browning of WAT are PRDM16, PPARγ and PGC-1α via various cellular and molecular mechanism. Presented review article includes the detailed elaborative aspect of genes and proteins involved in conversion of WAT to BAT.

Although lineage reprogramming from one cell type to another is becoming a breakthrough technology for cell-based therapy, several limitations remain to be overcome, including the low conversion efficiency and subtype specificity. To address these, many studies have been conducted using genetics, chemistry, physics, and cell biology to control transcriptional networks, signaling cascades, and epigenetic modifications during reprogramming. Here, we summarize recent advances in cellular reprogramming and discuss future directions.

Interactions between macrophages and adipocytes in adipose tissue are critical for the regulation of energy metabolism and obesity. Macrophage polarization induced by cold or other stimulations can drive metabolic reprogramming of adipocytes, browning, and thermogenesis. Accordingly, investigating the roles of macrophages and adipocytes in the maintenance of energy homeostasis is critical for the development of novel therapeutic approaches specifically targeting macrophages in metabolic disorders such as obesity. Current review outlines macrophage polarization not only regulates the release of central nervous system and inflammatory factors, but controls mitochondrial function, and other factor that induce metabolic reprogramming of adipocytes and maintain energy homeostasis. We also emphasized on how the adipocytes conversely motivate the polarization of macrophage. Exploring the interactions between adipocytes and macrophages may provide new therapeutic strategies for the management of obesity-related metabolic diseases.

Aim: To study the expression of histone methyltransferase SMYD1 in white adipose tissue (WAT) and brown adipose tissue and during differentiation of preadipocytes to white and beige phenotypes. Methods: C57BL/6J mice fed a high-fat diet (and exposed to cold) and 3T3-L1 cells stimulated to differentiate into white and beige adipocytes were used. Results: SMYD1 expression increased in WAT of high-fat diet fed mice and in WAT and brown adipose tissue of cold-exposed mice, suggesting its role in thermogenesis. SMYD1 expression was higher in beige adipocytes than in white adipocytes, and its silencing leads to a decrease in mitochondrial content and in Pgc-1α expression. Conclusion: These data suggest a novel role for SMYD1 as a positive regulator of energy control in adipose tissue.

Adipose tissue macrophages can promote beige adipose thermogenesis by altering local sympathetic activity. Here, we perform sympathectomy in mice and further eradicate subcutaneous adipose macrophages and discover that these macrophages have a direct beige-promoting function that is independent of sympathetic system. We further identify adipocyte Ets1 as a vital mediator in this process. The anti-inflammatory M2 macrophages suppress Ets1 expression in adipocytes, transcriptionally activate mitochondrial biogenesis, as well as suppress mitochondrial clearance, thereby increasing the mitochondrial numbers and promoting the beiging process. Male adipocyte Ets1 knock-in mice are completely cold intolerant, whereas male mice lacking Ets1 in adipocytes show enhanced energy expenditure and are resistant to metabolic disorders caused by high-fat-diet. Our findings elucidate a direct communication between M2 macrophages and adipocytes, and uncover a function for Ets1 in responding to macrophages and negatively governing mitochondrial content and beige adipocyte formation.

Mutation of the PRDM16 gene causes human dilated and non-compaction cardiomyopathy. The PRDM16 protein is a transcriptional regulator that affects cardiac development via Tbx5 and Hand1, thus regulating myocardial structure. The biallelic inactivation of Prdm16 induces severe cardiac dysfunction with post-natal lethality and hypertrophy in mice. The early pathological events that occur upon Prdm16 inactivation have not been explored.

This study performed in-depth pathophysiological and molecular analyses of male and female Prdm16csp1/wt mice that carry systemic, monoallelic Prdm16 gene inactivation. We systematically assessed early molecular changes through transcriptomics, proteomics, and metabolomics. Kinetic modelling of cardiac metabolism was performed in silico with CARDIOKIN. Prdm16csp1/wt mice are viable up to 8 months, develop hypoplastic hearts, and diminished systolic performance that is more pronounced in female mice. Prdm16csp1/wt cardiac tissue of both sexes showed reductions in metabolites associated with amino acid as well as glycerol metabolism, glycolysis, and the tricarboxylic acid cycle. Prdm16csp1/wt cardiac tissue revealed diminished glutathione (GSH) and increased inosine monophosphate (IMP) levels indicating oxidative stress and a dysregulated energetics, respectively. An accumulation of triacylglycerides exclusively in male Prdm16csp1/wt hearts suggests a sex-specific metabolic adaptation. Metabolic modelling using CARDIOKIN identified a reduction in fatty acid utilization in males as well as lower glucose utilization in female Prdm16csp1/wt cardiac tissue. On the level of transcripts and protein expression, Prdm16csp1/wt hearts demonstrate an up-regulation of pyridine nucleotide-disulphide oxidoreductase domain 2 (Pyroxd2) and the transcriptional regulator pre-B-cell leukaemia transcription factor interacting protein 1 (Pbxip1). The strongest concordant transcriptional up-regulation was detected for Prdm16 itself, probably through an autoregulatory mechanism.

Monoallelic, global Prdm16 mutation diminishes cardiac performance in Prdm16csp1/wt mice. Metabolic alterations and transcriptional dysregulation in Prdm16csp1/wt affect cardiac tissue. Female Prdm16csp1/wt mice develop a more pronounced phenotype, indicating sexual dimorphism at this early pathological window. This study suggests that metabolic dysregulation is an early event in the PRDM16 associated cardiac pathology.

PRDM16 is a dynamic transcriptional regulator of various stem cell niches, including adipocytic, hematopoietic, cardiac progenitors, and neural stem cells. PRDM16 has been suggested to contribute to 1p36 deletion syndrome, one of the most prevalent subtelomeric microdeletion syndromes. We report a patient with a de novo nonsense mutation in the PRDM16 coding sequence, accompanied by lissencephaly and microcephaly features. Human stem cells were genetically modified to mimic this mutation, generating cortical organoids that exhibited altered cell cycle dynamics. RNA sequencing of cortical organoids at day 32 unveiled changes in cell adhesion and WNT-signaling pathways. ChIP-seq of PRDM16 identified binding sites in postmortem human fetal cortex, indicating the conservation of PRDM16 binding to developmental genes in mice and humans, potentially at enhancer sites. A shared motif between PRDM16 and LHX2 was identified and further examined through comparison with LHX2 ChIP-seq data from mice. These results suggested a collaborative partnership between PRDM16 and LHX2 in regulating a common set of genes and pathways in cortical radial glia cells, possibly via their synergistic involvement in cortical development.

γδT17 cells are a subset of γδT cells producing IL-17, which is crucial for protection against bacterial and fungal infections. It has recently been shown that γδT17 cells have enriched lipid storage and lipid metabolism. However, the regulation of γδT17 cell function and differentiation with respect to lipids remains unknown. Here, we report that PRDM16 is a critical regulator of γδT17 cell differentiation, controlling type 17 immunity gene expression program and lipid-dependent cell fitness. We demonstrated that γδT17 cells have higher lipid-dependent cell fitness, which is negatively correlated with the expression of Prdm16. Loss of Prdm16 enhances the function and differentiation of γδT17 cells, and increases their fitness in lipid-rich environments. Specifically, loss of Prdm16 exacerbates development of psoriasis in the skin, a lipid-rich organ, and Prdm16 controls lipid-mediated differentiation of Vγ4+ γδT17 cells, which are the major source of IL-17 during the onset of psoriasis. Our study highlights the potential impact of PRDM16 on lipid-dependent fitness and protective immune function of γδT cells and also on the immunotherapy of psoriasis and inflammatory diseases.

Long-term consumption of a high-fat diet (HFD) disrupts energy homeostasis and leads to weight gain. The fat mass and obesity-associated (FTO) gene has been consistently identified to be associated with HFD-induced obesity. The hypothalamus is crucial for regulating energy balance, and HFD-induced hypothalamic leptin resistance contributes to obesity. FTO, an N6-methyladenosine (m6A) RNA methylation regulator, may be a key mediator of leptin resistance. However, the exact mechanisms remain unclear. Therefore, the present study aims to investigate the association between FTO and leptin resistance. After HFD or standard diet (SD) feeding in male mice for 22 weeks, m6A-sequencing and western blotting assays were used to identify target genes and assess protein level, and molecular interaction changes. CRISPR/Cas9 gene knockout system was employed to investigate the potential function of FTO in leptin resistance and obesity. Our data showed that chemokine (C-X3-C motif) ligand 1 (CX3CL1) was a direct downstream target of FTO-mediated m6A modification. Furthermore, upregulation of FTO/CX3CL1 and suppressor of cytokine signaling 3 (SOCS3) in the hypothalamus impaired leptin-signal transducer and activator of transcription 3 signaling, resulting in leptin resistance and obesity. Compared to wild-type (WT) mice, FTO deficiency in leptin receptor-expressing neurons of the hypothalamus significantly inhibited the upregulation of CX3CL1 and SOCS3, and partially ameliorating leptin resistance under HFD conditions. Our findings reveal that FTO involved in the hypothalamic leptin resistance and provides novel insight into the function of FTO in the contribution to hypothalamic leptin resistance and obesity.

The coexistence of brown adipocytes with low and high thermogenic activity is a fundamental feature of brown adipose tissue heterogeneity and plasticity. However, the mechanisms that govern thermogenic adipocyte heterogeneity and its significance in obesity and metabolic disease remain poorly understood. Here we show that in male mice, a population of transcription factor jun-B (JunB)-enriched (JunB+) adipocytes within the brown adipose tissue exhibits lower thermogenic capacity compared to high-thermogenic adipocytes. The JunB+ adipocyte population expands in obesity. Depletion of JunB in adipocytes increases the fraction of adipocytes exhibiting high thermogenic capacity, leading to enhanced basal and cold-induced energy expenditure and protection against diet-induced obesity and insulin resistance. Mechanistically, JunB antagonizes the stimulatory effects of PPARγ coactivator-1α on high-thermogenic adipocyte formation by directly binding to the promoter of oestrogen-related receptor alpha, a PPARγ coactivator-1α downstream effector. Taken together, our study uncovers that JunB shapes thermogenic adipocyte heterogeneity, serving a critical role in maintaining systemic metabolic health.

Activation of β-adrenergic (β-AR) signaling induces fight-or-flight stress responses which include enhancement of cardiopulmonary function, metabolic regulation, and muscle contraction. Classical dogma for β-AR signaling has dictated that the receptor-mediated response results in an acute and transient signal. However, more recent studies support more wide-ranging roles for β-AR signaling with long-term effects including cell differentiation that requires precisely timed and coordinated integration of many signaling pathways that culminate in precise epigenomic chromatin modifications. In this chapter, we discuss cold stress/β-AR signaling-induced epigenomic changes in adipose tissues that influence adaptive thermogenesis. We highlight recent studies showing dual roles for the histone demethylase JMJD1A as a mediator of both acute and chronic thermogenic responses to cold stress, in two distinct thermogenic tissues, and through two distinct molecular mechanisms. β-AR signaling not only functions through transient signals during acute stress responses but also relays a more sustained signal to long-term adaptation to environmental changes.

The increasing incidence of metabolic diseases, including obesity, type 2 diabetes mellitus (T2DM), and non-alcoholic fatty liver disease (NAFLD), in the past decade is a serious concern worldwide. Disruption of cellular protein homeostasis has been considered as a crucial contributor to the pathogenesis of metabolic diseases. To maintain protein homeostasis, cells have evolved multiple dynamic and self-regulating quality control processes to adapt new environmental conditions and prevent prolonged damage. Among them, the ubiquitin proteasome system (UPS), the primary proteolytic pathway for degradation of aberrant proteins via ubiquitination, has an essential role in maintaining cellular homeostasis in response to intracellular stress. Correspondingly, accumulating evidences have shown that dysregulation of ubiquitination can aggravate various metabolic derangements in many tissues, including the liver, skeletal muscle, pancreas, and adipose tissue, and is involved in the initiation and progression of diverse metabolic diseases. In this part, we will summarize the role of ubiquitination in the pathogenesis of metabolic diseases, including obesity, T2DM and NAFLD, and discuss its potential as a therapeutic target.

The foundations of cell reprogramming were laid by Yamanaka and co-workers, who showed that somatic cells can be reprogrammed into pluripotent cells (induced pluripotency). Since this discovery, the field of regenerative medicine has seen advancements. For example, because they can differentiate into multiple cell types, pluripotent stem cells are considered vital components in regenerative medicine aimed at the functional restoration of damaged tissue. Despite years of research, both replacement and restoration of failed organs/ tissues have remained elusive scientific feats. However, with the inception of cell engineering and nuclear reprogramming, useful solutions have been identified to counter the need for compatible and sustainable organs. By combining the science underlying genetic engineering and nuclear reprogramming with regenerative medicine, scientists have engineered cells to make gene and stem cell therapies applicable and effective. These approaches have enabled the targeting of various pathways to reprogramme cells, i.e., make them behave in beneficial ways in a patient-specific manner. Technological advancements have clearly supported the concept and realization of regenerative medicine. Genetic engineering is used for tissue engineering and nuclear reprogramming and has led to advances in regenerative medicine. Targeted therapies and replacement of traumatized , damaged, or aged organs can be realized through genetic engineering. Furthermore, the success of these therapies has been validated through thousands of clinical trials. Scientists are currently evaluating induced tissue-specific stem cells (iTSCs), which may lead to tumour-free applications of pluripotency induction. In this review, we present state-of-the-art genetic engineering that has been used in regenerative medicine. We also focus on ways that genetic engineering and nuclear reprogramming have transformed regenerative medicine and have become unique therapeutic niches.

Brown and beige adipocytes produce heat from substrates such as fatty acids and glucose. Such heat productions occur in response to various stimuli and are called adaptive non-shivering thermogenesis. This review introduces mechanisms known to regulate brown and beige adipocyte thermogenesis. Leptin and fibroblast growth factor 21 (FGF21) are examples of periphery-derived humoral factors that act on the central nervous system (CNS) and increase brown adipose tissue (BAT) thermogenesis. Additionally, neuronal signals such as those induced by intestinal cholecystokinin and hepatic peroxisome proliferator-activated receptor γ travel through vagal afferent-CNS-sympathetic efferent-BAT pathways and increase BAT thermogenesis. By contrast, some periphery-derived humoral factors (ghrelin, adiponectin, plasminogen activator inhibitor-1, and soluble leptin receptor) act also on CNS but inhibit BAT thermogenesis. Neuronal signals also reduce BAT sympathetic activities and BAT thermogenesis, one such example being signals derived by hepatic glucokinase activation. Beige adipocytes can be induced by myokines (interleukin 6, irisin, and β-aminoisobutyric acid), hepatokines (FGF21), and cardiac-secreted factors (brain natriuretic peptide). Cold temperature and leptin also stimulate beige adipocytes via sympathetic activation. Further investigation on inter-organ communication involving adipocyte thermogenesis may lead to the elucidation of how body temperature is regulated and, moreover, to the development of novel strategies to treat metabolic disorders.

Brown adipose tissue (BAT) dissipates energy as heat, contributing to temperature control, energy expenditure, and systemic homeostasis. In adult humans, BAT mainly exists in supraclavicular areas and its prevalence is associated with cardiometabolic health. However, the developmental origin of supraclavicular BAT remains unknown. Here, using genetic cell marking in mice, we demonstrate that supraclavicular brown adipocytes do not develop from the Pax3+/Myf5+ epaxial dermomyotome that gives rise to interscapular BAT (iBAT). Instead, the Tbx1+ lineage that specifies the pharyngeal mesoderm marks the majority of supraclavicular brown adipocytes. Tbx1Cre-mediated ablation of peroxisome proliferator-activated receptor gamma (PPARγ) or PR/SET Domain 16 (PRDM16), components of the transcriptional complex for brown fat determination, leads to supraclavicular BAT paucity or dysfunction, thus rendering mice more sensitive to cold exposure. Moreover, human deep neck BAT expresses higher levels of the TBX1 gene than subcutaneous neck white adipocytes. Taken together, our observations reveal location-specific developmental origins of BAT depots and call attention to Tbx1+ lineage cells when investigating human relevant supraclavicular BAT.

The marker genes associated with white adipocytes and brown adipocytes have been previously identified; however, these markers have not been updated in several years, and the differentiation process of preadipocytes remains relatively fixed. Consequently, there has been a lack of exploration into alternative differentiation schemes. In this particular study, we present a transcriptional signature specific to brown adipocytes and white adipocytes. Notably, our findings reveal that ZNF497, ZIC1, ZFY, UTY, USP9Y, TXLNGY, TTTY14, TNNT3, TNNT2, TNNT1, TNNI1, TNNC1, TDRD15, SOX11, SLN, SFRP2, PRKY, PAX3KLHL40, PAX3, INKA2-AS1, SOX11, and TDRD15 exhibit high expression levels in brown adipocytes. XIST, HOXA10, PCAT19, HOXA7, PLSCR3, and AVPR1A exhibited high expression levels in white adipocytes, suggesting their potential as novel marker genes for the transition from white to brown adipocytes. Furthermore, our analysis revealed the coordinated activation of several pathways, including the PPAR signaling pathway, focal adhesion, retrograde endocannabinoid signaling, oxidative phosphorylation, PI3K-Akt signaling pathway, and thermogenesis pathways, in brown adipocytes. Moreover, in contrast to prevailing culture techniques, we conducted a comparative analysis of the differentiation protocols for white preadipocytes and brown preadipocytes, revealing that the differentiation outcome remained unaffected by the diverse culture schemes employed. However, the expression levels of certain marker genes in both adipocyte types were found to be altered. This investigation not only identified potential novel marker genes for adipocytes but also examined the impact of different differentiation methods on preadipocyte maturation. Consequently, these findings offer significant insights for further research on the differentiation processes of diverse adipocyte subtypes.

Adipose tissue transplantation shows great therapeutic potential in reversing localized scleroderma-associated skin fibrosis. Brown adipose tissue (BAT) can specifically secrete various cytokines against fibrosis, but its therapeutic potential in improving skin fibrosis has not yet been demonstrated. In this study, we have demonstrated the superior therapeutic efficacy of BAT transplantation for sclerotic skin by transplanting two distinct types of adipose tissue. In comparison to the white adipose tissue (WAT) group, mice treated with BAT transplantation exhibited a significant reduction in dermal thickness. BAT transplantation effectively reverses skin sclerosis through mechanisms involving inflammation reduction, promotion of angiogenesis, inhibition of myofibroblast accumulation, and collagen deposition. This therapeutic effect can be attributed to its unique paracrine effects. Furthermore, transcriptome sequencing (RNA-Seq) revealed upregulation of pathways associated with lipogenesis and fatty acid metabolism in BAT while downregulating pathways are related to transforming growth factor β(TGF-β), epithelial-mesenchymal transition (EMT), and inflammatory response. These findings suggest that BAT transplantation holds great promise as a novel approach for localized scleroderma treatment.

Sympathetic innervation is essential for the development of functional beige fat that maintains body temperature and metabolic homeostasis, yet the molecular mechanisms controlling this innervation remain largely unknown. Here, we show that adipocyte YAP/TAZ inhibit sympathetic innervation of beige fat by transcriptional repression of neurotropic factor S100B. Adipocyte-specific loss of Yap/Taz induces S100b expression to stimulate sympathetic innervation and biogenesis of functional beige fat both in subcutaneous white adipose tissue (WAT) and browning-resistant visceral WAT. Mechanistically, YAP/TAZ compete with C/EBPβ for binding to the zinc finger-2 domain of PRDM16 to suppress S100b transcription, which is released by adrenergic-stimulated YAP/TAZ phosphorylation and inactivation. Importantly, Yap/Taz loss in adipocytes or AAV-S100B overexpression in visceral WAT restricts both age-associated and diet-induced obesity, and improves metabolic homeostasis by enhancing energy expenditure of mice. Together, our data reveal that YAP/TAZ act as a brake on the beige fat innervation by blocking PRDM16-C/EBPβ-mediated S100b expression.