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Cocoa extract (CE) offers several health benefits, such as antiobesity and improved glucose intolerance. However, the mechanisms remain unclear. Adipose tissue includes white adipose tissue (WAT) and brown adipose tissue. Brown adipose tissue leads to body fat reduction by metabolizing lipids to heat via uncoupling protein 1 (UCP1). The conversion of white adipocytes into brown-like adipocytes (beige adipocytes) is called browning, and it contributes to the anti-obesity effect and improved glucose tolerance. This study aimed to evaluate the effect of CE on glucose tolerance in terms of browning. We found that dietary supplementation with CE improved glucose intolerance in mice fed a high-fat diet, and it increased the expression levels of Ucp1 and browning-associated gene in inguinal WAT. Furthermore, in primary adipocytes of mice, CE induced Ucp1 expression through β3-adrenergic receptor stimulation. These results suggest that dietary CE improves glucose intolerance by inducing browning in WAT., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

Background: The Arg64 allele of the rs4994 (Trp64Arg) variant in the β3-adrenergic receptor (ADRB3) gene is involved in the control of energy balance by altering lipolysis and thermogenesis in adipocytes, ultimately contributing to the development of obesity. The objective of our study was to investigate the association between the rs4994 variant of the ADRB3 gene and obesity in Hanoi preschool-age children, adjusting for their eating behaviors., Methods: A cross-sectional study was performed involving 708 children with normal weight and 304 children with obesity aged 3-5 years from 36 kindergartens in Hanoi, Vietnam. Cheek mucosa cell samples were used for DNA extraction, and genotyping at the ADRB3-rs4994 locus was performed using the polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP). Eating behaviors were assessed using the Children's Eating Behaviour Questionnaire (CEBQ). Binary logistic regression analysis was employed to examine the association between the rs4994 variant and obesity, adjusting for confounding factors such as age, sex, residence, birth weight, and eating behaviors., Results: The frequency of the C allele in the group with obesity was 16.4%, which was higher than in the control group (11.7%, P = 0.003). Children with the CC genotype exhibited significantly greater weight and weight-for-age Z-score compared to those with the TT and TC genotypes (P = 0.004 and 0.03, respectively). Following univariate and multivariate analyses adjusted for age, sex, residence, birth weight, and eating behaviors, a significant association between the rs4994 variant and obesity was observed (P < 0.05)., Conclusions: This study indicated that the ADRB3-rs4994 variant can be considered as an independent risk factor for obesity in Vietnamese preschool children., (© 2024. The Author(s).)

Objective and Design: Kinin B1 receptor (B1R) has a key role in adipocytes to protect against obesity and glycemic metabolism, thus becoming a potential target for regulation of energy metabolism and adipose tissue thermogenesis., Material or Subjects: Kinin B1 knockout mice (B1KO) were subjected to acute induction with CL 316,243 and chronic cold exposure., Methods: Metabolic and histological analyses, gene and protein expression and RNA-seq were performed on interscapular brown adipose tissue (iBAT) and inguinal white adipose tissue (iWAT) of mice., Results: B1KO mice, under acute effect of CL 316,243, exhibited increased energy expenditure and upregulated thermogenic genes in iWAT. They were also protected from chronic cold, showing enhanced non-shivering thermogenesis with increased iBAT mass (~ 90%) and recruitment of beige adipocytes in iWAT (~ 50%). Positive modulation of thermogenic and electron transport chain genes, reaching a 14.5-fold increase for Ucp1 in iWAT. RNA-seq revealed activation of the insulin signaling pathways for iBAT and oxidative phosphorylation, tricarboxylic acid cycle, and browning pathways for iWAT., Conclusion: B1R deficiency induced metabolic and gene expression alterations in adipose tissue, activating thermogenic pathways and increasing energy metabolism. B1R antagonists emerge as promising therapeutic targets for regulating obesity and associated metabolic disorders, such as inflammation and diabetes., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Enhancing white adipose tissue (WAT) browning combats obesity. The RIIβ subunit of cAMP-dependent protein kinase (PKA) is primarily expressed in the brain and adipose tissue. Deletion of the hypothalamic RIIβ gene centrally induces WAT browning, yet the peripheral mechanisms mediating this process remain unexplored. Methods: This study investigates the mechanisms underlying WAT browning in RIIβ-KO mice. Genetic approaches such as β3-adrenergic receptors (β3ARs) deletion and sympathetic denervation of WAT were utilized. Genome-wide transcriptomic sequencing and bioinformatic analysis were employed to identify potential mediators of WAT browning. siRNA assays were employed to knock down mTOR and lipin1 in vitro , while AAV-shRNAs were used for the same purpose in vivo . Results: We found that WAT browning substantially contributes to the lean and obesity-resistant phenotypes of RIIβ-KO mice. The WAT browning can be dampened by β 3 ARs deletion or WAT sympathetic denervation. We identified that adipocytic mTOR and lipin1 may act as mediators of the WAT browning. Inhibition of mTOR or lipin1 abrogates WAT browning and hinders the lean phenotype of RIIβ-KO mice. In human subcutaneous white adipocytes and mouse white adipocytes, β 3 AR stimulation can activate mTOR and causes lipin1 nuclear translocation; knockdown of mTOR and Lipin1 mitigates WAT browning-associated gene expression, impedes mitochondrial activity. Moreover, mTOR knockdown reduces lipin1 level and nuclear translocation, indicating that lipin1 may act downstream of mTOR. Additionally, in vivo knockdown of mTOR and Lipin1 diminished WAT browning and increased adiposity. Conclusions: The β 3 AR-activated mTOR-lipin1 axis mediates WAT browning, offering new insights into the molecular basis of PKA-regulated WAT browning. These findings provide potential adipose target candidates for the development of drugs to treat obesity., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background: Sympathetic activation of brown adipose tissue (BAT) thermogenesis can ameliorate obesity and related metabolic abnormalities. However, crucial subtypes of the β-adrenergic receptor (AR), as well as effects of its genetic variants on functions of BAT, remains unclear in humans. We conducted association analyses of genes encoding β-ARs and BAT activity in human adults., Methods: Single nucleotide polymorphisms (SNPs) in β1-, β2-, and β3-AR genes (ADRB1, ADRB2, and ADRB3) were tested for the association with BAT activity under mild cold exposure (19 °C, 2 h) in 399 healthy Japanese adults. BAT activity was measured using fluorodeoxyglucose-positron emission tomography and computed tomography (FDG-PET/CT). To validate the results, we assessed the effects of SNPs in the two independent populations comprising 277 healthy East Asian adults using near-infrared time-resolved spectroscopy (NIR TRS ) or infrared thermography (IRT). Effects of SNPs on physiological responses to intensive cold exposure were tested in 42 healthy Japanese adult males using an artificial climate chamber., Results: We found a significant association between a functional SNP (rs1042718) in ADRB2 and BAT activity assessed with FDG-PET/CT (p < 0.001). This SNP also showed an association with cold-induced thermogenesis in the population subset. Furthermore, the association was replicated in the two other independent populations; BAT activity was evaluated by NIR TRS or IRT (p < 0.05). This SNP did not show associations with oxygen consumption and cold-induced thermogenesis under intensive cold exposure, suggesting the irrelevance of shivering thermogenesis. The SNPs of ADRB1 and ADRB3 were not associated with these BAT-related traits., Conclusions: The present study supports the importance of β2-AR in the sympathetic regulation of BAT thermogenesis in humans. The present collection of DNA samples is the largest to which information on the donor's BAT activity has been assigned and can serve as a reference for further in-depth understanding of human BAT function., (© 2024. The Author(s).)

After exposure to cold stress, animals enhance the production of beige adipocytes and expedite thermogenesis, leading to improved metabolic health. Although brown adipose tissue in rodents is primarily induced by β3 -adrenergic receptor ( ADRB3 ) stimulation, the activation of major β -adrenergic receptors ( ADRBs ) in pigs has been a topic of debate. To address this, we developed overexpression vectors for ADRB1 , ADRB2 , and ADRB3 and silenced the expression of these receptors to observe their effects on the adipogenic differentiation stages of porcine preadipocytes. Our investigation revealed that cold stress triggers the transformation of subcutaneous white adipose tissue to beige adipose tissue in pigs by modulating adrenergic receptor levels. Meanwhile, we found that ADRB3 promotes the transformation of white adipocytes into beige adipocytes. Notably, ADRB3 enhances the expression of beige adipose tissue marker genes, consequently influencing cellular respiration and metabolism by regulating lipolysis and mitochondrial expression. Therefore, ADRB3 may serve as a pivotal gene in animal husbandry and contribute to the improvement of cold intolerance in piglets.

Background: Neoadjuvant chemotherapy (NAC) has become a standard treatment strategy for breast cancer (BC). However, owing to the high heterogeneity of these tumors, it is unclear which patient population most likely benefit from NAC. Multi-omics offer an improved approach to uncovering genomic and transcriptomic changes before and after NAC in BC and to identifying molecular features associated with NAC sensitivity., Methods: We performed whole-exome and RNA sequencing on 233 samples (including matched pre- and post-treatment tumors) from 50 BC patients with rigorously defined responses to NAC and analyzed changes in the multi-omics landscape. Molecular features associated with NAC response were identified and validated in a larger internal, and two external validation cohorts, as well as in vitro experiments., Results: The most frequently altered genes were TP53, TTN, and MUC16 in both pre- and post-treatment tumors. In comparison with pre-treatment tumors, there was a significant decrease in C > A transversion mutations in post-treatment tumors (P = 0.020). NAC significantly decreased the mutation rate (P = 0.006) of the DNA repair pathway and gene expression levels (FDR = 0.007) in this pathway. NAC also significantly changed the expression level of immune checkpoint genes and the abundance of tumor-infiltrating immune and stroma cells, including B cells, activated dendritic cells, γδT cells, M2 macrophages and endothelial cells. Furthermore, there was a higher rate of C > T substitutions in NAC nonresponsive tumors than responsive ones, especially when the substitution site was flanked by C and G. Importantly, there was a unique amplified region at 8p11.23 (containing ADGRA2 and ADRB3) and a deleted region at 3p13 (harboring FOXP1) in NAC nonresponsive and responsive tumors, respectively. Particularly, the CDKAL1 missense variant P409L (p.Pro409Leu, c.1226C > T) decreased BC cell sensitivity to docetaxel, and ADGRA2 or ADRB3 gene amplifications were associated with worse NAC response and poor prognosis in BC patients., Conclusions: Our study has revealed genomic and transcriptomic landscape changes following NAC in BC, and identified novel biomarkers (CDKAL1 P409L , ADGRA2 and ADRB3) underlying chemotherapy resistance and poor prognosis, which could guide the development of personalized treatments for BC., (© 2024. The Author(s).)

The ADRB3 gene plays a role in energy expenditure by participating in lipolysis, which affects body composition and performance. The ADRB3 rs4994 polymorphism has been studied in groups of athletes, overweight individuals, and obese and diabetic patients, but it has not been studied in young and healthy adults so far. In the present study, we examined the association of ADRB3 rs4994 polymorphism with body composition, somatotype, cardiorespiratory fitness and physical activity in young, healthy adults ( N = 304). All subjects had anthropometric measurements, and somatotypes were assessed using the Heath-Carter method. In addition, cardiorespiratory fitness and physical activity levels were assessed. Genotyping for the ADRB3 gene was performed using a PCR-RFLP method. In the male group, body components were associated with the Trp64Trp genotype (waist circumference ( p = 0.035), hip circumference ( p = 0.029), BF (%) ( p = 0.008), and BF (kg) ( p = 0.010), BMI ( p = 0.005), WHtR ( p = 0.021), and BAI ( p = 0.006)). In addition, we observed that the Trp64Trp genotype was associated with somatotype components ( p = 0.013). In contrast, the Arg allele was associated with the ectomorphic components (0.006). We also observed a positive impact of the Trp64Trp genotype with maximal oxygen uptake ( p = 0.023) and oxygen pulse ( p = 0.024). We observed a negative relationship of the Trp64Trp genotype in the female group with reported moderate-intensity exercise ( p = 0.036). In conclusion, we found an association of the Trp64 allele with anthropometric traits, somatotype and parameters describing physical performance in the male group. In the female subpopulation, we only found an effect of the polymorphism Trp64Arg on the level of physical activity for moderate-intensity exercise.

Neuroblastoma (NB) is a heterogeneous extracranial tumor occurring in childhood. A distinctive feature of NB tumors is their neuroendocrine ability to secrete catecholamines, which in turn, via β-adrenergic receptors ligation, may affect different signaling pathways in tumor microenvironment (TME). It was previously demonstrated that specific antagonism of β3-adrenergic receptor (β3-AR) on NB tumor cells affected tumor growth and progression. Here, in a murine syngeneic model of NB, we aimed to investigate whether the β3-AR modulation influenced the host immune system response against tumor. Results demonstrated that β3-AR antagonism lead to an immune response reactivation, partially dependent on the PD-1/PD-L1 signaling axis involvement. Indeed, β3-AR blockade on tumor-infiltrating lymphocytes (TILs) dampened their ability to secrete IFN-γ, which in turn reduced the PD-L1 expression, caused by TILs infiltration, on NB tumor cells. Further investigations, through a genomic analysis on NB patients, showed that high ADRB3 gene expression correlates with worse clinical outcome compared to the low expression group, and that ADRB3 gene expression affects different immune-related pathways. Overall, results indicate that β3-AR in NB TME is able to modulate the interaction between tumor and host immune system, and that its antagonism hits multiple pro-tumoral signaling pathways., (© 2023. The Author(s).)

Objective: Coronary artery disease (CAD) is a the most common type of heart disease, and is associated with the highest mortality rate. The role of the β 3 -adrenergic receptor gene ( ADRB3 ) in energy homeostasis and lipolysis suggests that it may be associated with obesity, insulin resistance, diabetes, and hypertension. Herein, we sought to examine the relationship between CAD and variants of the ADRB3 gene in individuals with Han and Uygur ethnicities in China. Methods: All 1022 participants were genotyped for two ADRB3 single nucleotide polymorphisms (SNPs; rs1892818 and rs9693898) using real-time polymerase chain reaction (TaqMan). Uygur (259 CAD patients, 161 control group) and Han (308 CAD patients, 294 control group) were included in two case-control studies. We subsequently developed a predictive model using ADRB3 genetic variation and clinical variables to predict risk of CAD. Results: The rs1892818 CT genotype (8.5% vs 3.9%, p  = 0.019) and T allele (4.3% vs 1.9%, p  = 0.021) were more frequently detected in the control subjects compared to CAD patients of the Han population but not in the Uygur population. The rs9693898 was not associated with CAD in either ethnic population. Logistic regression analysis further demonstrated that carriers of the rs1892818 CT genotype had a lower risk of CAD than did those with the CC genotype (CT vs CC, p  = 0.044, odds ratio [OR] = 0.441, 95% confidence interval [CI]: 0.199-0.976). Using this data, we constructed a predictive nomogram model for CAD with an area under the curve (95% CI) of 0.722 (0.682, 0.761). Conclusions: Our results suggest that rs1892818 is associated with CAD in the Han population and that the CT genotype of rs1892818 may serve as a protective factor for CAD in Han individuals. The proposed nomograms can be used for the prediction of CAD in this population.

Aims: β 3 -adrenoceptors (ARs) are an important drug target for the treatment of overactive bladder syndrome (OAB) and are under investigation for other indications. The human β 3 -AR gene is polymorphic; an exchange of amino acid tryptophan (Trp) for arginine (Arg) in position 64 of the receptor protein is the most frequent and best-studied polymorphism. A narrative review on the impact of β 3 -AR polymorphisms on urological disease and its treatment is presented., Results: Two out of four studies have reported that the 64Arg allele was found more frequently in subjects with OAB than in healthy controls. A large study in a highly selective population (men undergoing prostatectomy for cancer treatment) did not confirm this. On the other hand, studies examining symptom severity typically found little difference between 64Arg and 64Trp carriers. In vitro studies with endogenously expressed β 3 -AR reported a decreased lipolytic response in human adipose tissue. Studies with heterologously expressed receptors sometimes found a decreased responsiveness to agonists including β 3 -AR agonists, but others did not confirm that., Conclusions: The overall evidence points to carriers of the 64Arg genotype expressing fewer and/or hypofunctional β 3 -ARs and being associated with the presence of OAB but such findings were only detected inconsistently. If this hypofunctionality exists, the consequences may be of insufficient magnitude to allow a robust detection. Only adequately powered studies comparing responses with a β 3 -AR agonist in 64Arg carriers versus wild-type patients can address this., (© 2022 The Authors. Neurourology and Urodynamics published by Wiley Periodicals LLC.)

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., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A high-fat diet is believed to be a risk factor for hypertension through inducing obesity. It has been reported that variants of the fat mass and obesity-associated (FTO) and beta-3 adrenergic receptor (B3AR) genes are associated with obesity and blood pressure. The purpose of this study was to investigate the effect of dietary fat on blood pressure with or without the variant of the FTO and B3AR genes. A total of 227 healthy Japanese women aged 18 to 64 years were recruited for measurement of nutrient intake and blood pressure. The single nucleotide polymorphism rs9939609 of the FTO gene and rs4994 of the B3AR gene were genotyped. Spearman's rank correlation coefficient was applied to investigate the relationship between fat intake and blood pressure. A hierarchical multiple regression analysis was performed to determine whether the genotype interacts with fat intake to affect blood pressure. No significant correlations were found between fat intake and either systolic or diastolic blood pressure. A significant negative correlation was found between fat intake and both blood pressures in the FTO-gene-variant group, but not in the normal-FTO-gene group. In hierarchical multiple regression analysis, the interaction of fat intake and the gene variant showed significance, and the change in coefficient of determination (R 2 ) was significantly increased with increases of the interaction variable. These results indicate that the effect of fat intake on blood pressure may be modified by the variant of the FTO gene such that a high-fat diet intake may be associated with a decrease of systolic and diastolic blood pressure in healthy Japanese women with the FTO variant. Our results did not support the hypothesis that a high-fat diet increases blood pressure.

Cold exposure triggers neogenesis in classic interscapular brown adipose tissue (iBAT) that involves activation of β1-adrenergic receptors, proliferation of PDGFRA+ adipose tissue stromal cells (ASCs), and recruitment of immune cells whose phenotypes are presently unknown. Single-cell RNA-sequencing (scRNA-seq) in mice identified three ASC subpopulations that occupied distinct tissue locations. Of these, interstitial ASC1 were found to be direct precursors of new brown adipocytes (BAs). Surprisingly, knockout of β1-adrenergic receptors in ASCs did not prevent cold-induced neogenesis, whereas pharmacological activation of the β3-adrenergic receptor on BAs was sufficient, suggesting that signals derived from mature BAs indirectly trigger ASC proliferation and differentiation. In this regard, cold exposure induced the delayed appearance of multiple macrophage and dendritic cell populations whose recruitment strongly correlated with the onset and magnitude of neogenesis across diverse experimental conditions. High-resolution immunofluorescence and single-molecule fluorescence in situ hybridization demonstrated that cold-induced neogenesis involves dynamic interactions between ASC1 and recruited immune cells that occur on the micrometer scale in distinct tissue regions. Our results indicate that neogenesis is not a reflexive response of progenitors to β-adrenergic signaling, but rather is a complex adaptive response to elevated metabolic demand within brown adipocytes., Competing Interests: RB, ER, HW, RP, JG No competing interests declared, (© 2022, Burl, Rondini et al.)

Background: The ADRB3 (β3-adrenergic receptors), which is predominantly expressed in brown adipose tissue (BAT), can activate BAT and improve metabolic health. Previous studies indicate that the endocrine function of BAT is associated with cardiac homeostasis and diseases. Here, we investigate the role of ADRB3 activation-mediated BAT function in cardiac remodeling., Methods: BKO (brown adipocyte-specific ADRB3 knockout) and littermate control mice were subjected to Ang II (angiotensin II) for 28 days. Exosomes from ADRB3 antagonist SR59230A (SR-exo) or agonist mirabegron (MR-exo) treated brown adipocytes were intravenously injected to Ang II-infused mice., Results: BKO markedly accelerated cardiac hypertrophy and fibrosis compared with control mice after Ang II infusion. In vitro, ADRB3 KO rather than control brown adipocytes aggravated expression of fibrotic genes in cardiac fibroblasts, and this difference was not detected after exosome inhibitor treatment. Consistently, BKO brown adipocyte-derived exosomes accelerated Ang II-induced cardiac fibroblast dysfunction compared with control exosomes. Furthermore, SR-exo significantly aggravated Ang II-induced cardiac remodeling, whereas MR-exo attenuated cardiac dysfunction. Mechanistically, ADRB3 KO or SR59230A treatment in brown adipocytes resulted an increase of iNOS (inducible nitric oxide synthase) in exosomes. Knockdown of iNOS in brown adipocytes reversed SR-exo-aggravated cardiac remodeling., Conclusions: Our data illustrated a new endocrine pattern of BAT in regulating cardiac remodeling, suggesting that activation of ADRB3 in brown adipocytes offers cardiac protection through suppressing exosomal iNOS.

Maternal lifestyle has been implicated as a predisposing factor in the development of metabolic disorders in adulthood. This lifestyle includes the immediate environment, physical activity and nutrition. Maternal nutrition has direct influence on the developmental programming through biochemical alterations and can lead to modifications in the fetal genome through epigenetic mechanisms. Imbalance in basic micro or macro nutrients due to famine or food deficiency during delicate gestational periods can lead to onset of metabolic syndrome including obesity. A major example is the Dutch famine which led to a serious metabolic disorder in adulthood of affected infants. Notably due to gene variants, individualized responses to nutritional deficiencies are unconventional, therefore intensifying the need to study nutritional genomics during fetal programming. Epigenetic mechanisms can cause hereditary changes without changing the DNA sequence; the major mechanisms include small non-coding RNAs, histone modifications and most stable of all is DNA methylation. The significance association between obesity and DNA methylation is through regulation of genes implicated in lipid and glucose metabolism either directly or indirectly by hypomethylation or hypermethylation. Examples include CPT1A, APOA2, ADRB3 and POMC. Any maternal exposure to malnutrition or overnutrition that can affect genes regulating major metabolic pathways in the fetus, will eventually cause underlying changes that can predispose or cause the onset of metabolic disorder in adulthood. In this review, we examined the interaction between nutrition during gestation and epigenetic programming of metabolic syndrome.

β-adrenergic receptor (β-AR) signaling plays predominant roles in modulating energy expenditure by triggering lipolysis and thermogenesis in adipose tissue, thereby conferring obesity resistance. Obesity is associated with diminished β3-adrenergic receptor (β3-AR) expression and decreased β-adrenergic responses, but the molecular mechanism coupling nutrient overload to catecholamine resistance remains poorly defined. Ten-eleven translocation (TET) proteins are dioxygenases that alter the methylation status of DNA by oxidizing 5-methylcytosine to 5-hydroxymethylcytosine and further oxidized derivatives. Here, we show that TET proteins are pivotal epigenetic suppressors of β3-AR expression in adipocytes, thereby attenuating the responsiveness to β-adrenergic stimulation. Deletion of all three Tet genes in adipocytes led to increased β3-AR expression and thereby enhanced the downstream β-adrenergic responses, including lipolysis, thermogenic gene induction, oxidative metabolism, and fat browning in vitro and in vivo. In mouse adipose tissues, Tet expression was elevated after mice ate a high-fat diet. Mice with adipose-specific ablation of all TET proteins maintained higher levels of β3-AR in both white and brown adipose tissues and remained sensitive to β-AR stimuli under high-fat diet challenge, leading to augmented energy expenditure and decreased fat accumulation. Consequently, they exhibited improved cold tolerance and were substantially protected from diet-induced obesity, inflammation, and metabolic complications, including insulin resistance and hyperlipidemia. Mechanistically, TET proteins directly repressed β3-AR transcription, mainly in an enzymatic activity-independent manner, and involved the recruitment of histone deacetylases to increase deacetylation of its promoter. Thus, the TET-histone deacetylase-β3-AR axis could be targeted to treat obesity and related metabolic diseases.

Background: Obesity is a complex genetic-based pediatric disorder which triggers life-threatening conditions. Therefore, the understanding the molecular mechanisms of obesity has been a significant approach in medicine. Computational methods allow rapid and comprehensive pathway analysis, which is important for generation of diagnosis and treatment of obesity., Methods and Results: Aims of our study are to comprehensively investigate genetic characteristics of obesity in children with non-syndromic, early-onset (< 7 years), and severe obesity (BMI-SDS > 3) through computational approaches. First, the mutational analyses of 41 of obesity-related genes in 126 children with non-syndromic early-onset severe obesity and 76 healthy non-obese controls were performed using the next generation sequencing (NGS) technique, and the NGS data analyzed by using bioinformatics methods. Then, the relationship between pathogenic variants and anthropometric/biochemical parameters was further evaluated. Obtained results demonstrated that the 15 genes (ADIPOQ, ADRB2, ADRB3, IRS1, LEPR, NPY, POMC, PPARG, PPARGC1A, PPARGC1B, PTPN1, SLC22A1, SLC2A4, SREBF1 and UCP1) which directly related to obesity found linked together via biological pathways and/or functions. Among these genes, IRS1, PPARGC1A, and SLC2A4 stand out as the most central ones. Furthermore, 12 of non-synonymous pathogenic variants, including six novels, were detected on ADIPOQ (G90S and D242G), ADRB2 (V87M), PPARGC1A (E680G, A477T, and R656H), UCP1 (Q44R), and IRS1 (R302Q, R301H, R301C, H250P, and H250N) genes., Conclusion: We propose that 12 of non-synonymous pathogenic variations detected on ADIPOQ, ADRB2, PPARGC1A, UCP1, and IRS1 genes might have a cumulative effect on the development and progression of obesity., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Metastatic tumors are mainly composed of neoplastic cells escaping from the primary tumor and inflammatory cells egressing from bone marrow. Cancer cell and inflammatory cell are remained in the state of immaturity during migration to distant organs. Here, we show that ADRB3 is crucial in cell mobilization and differentiation. Immunohistochemistry revealed ADRB3 expression is significantly more frequent in breast cancer tissues than in adjacent noncancerous tissues (92.1% vs. 31.5%). Expression of ADRB3 correlated with malignant degree, TNM stage and poor prognosis. Moreover, ADRB3 expression was markedly high in activated disseminated tumor cells, myeloid-derived suppressor cells (MDSCs), lymphocytes and neutrophil extracellular traps of patients. Importantly, ADRB3 promoted the expansion of MDSC through stimulation of bone marrow mobilization and inhibiting of the differentiation of immature myeloid cells. Furthermore, ADRB3 promoted MCF-7 cells proliferation and inhibited transdifferentiation into adipocyte-like cell by activating mTOR pathway. Ultimately, the MDSC-deficient phenotype of ADRB3 -/- PyMT mice was associated with impairment of mammary tumorigenesis and reduction in pulmonary metastasis. Collectively, ADRB3 promotes metastasis by inducing mobilization and inhibiting differentiation of both breast cancer cells and MDSCs., (© 2022. The Author(s).)

The dysregulation of energy homeostasis in obesity involves multihormone resistance. Although leptin and insulin resistance have been well characterized, catecholamine resistance remains largely unexplored. Murine β3-adrenergic receptor expression in adipocytes is orders of magnitude higher compared with that of other isoforms. While resistant to classical desensitization pathways, its mRNA (Adrb3) and protein expression are dramatically downregulated after ligand exposure (homologous desensitization). β3-Adrenergic receptor downregulation also occurs after high-fat diet feeding, concurrent with catecholamine resistance and elevated inflammation. This downregulation is recapitulated in vitro by TNF-α treatment (heterologous desensitization). Both homologous and heterologous desensitization of Adrb3 were triggered by induction of the pseudokinase TRIB1 downstream of the EPAC/RAP2A/PI-PLC pathway. TRIB1 in turn degraded the primary transcriptional activator of Adrb3, CEBPα. EPAC/RAP inhibition enhanced catecholamine-stimulated lipolysis and energy expenditure in obese mice. Moreover, adipose tissue expression of genes in this pathway correlated with body weight extremes in a cohort of genetically diverse mice and with BMI in 2 independent cohorts of humans. These data implicate a signaling axis that may explain reduced hormone-stimulated lipolysis in obesity and resistance to therapeutic interventions with β3-adrenergic receptor agonists.

Non-shivering thermogenesis (NST) is a heat generating process controlled by the mitochondria of brown adipose tissue (BAT). In the recent decade, 'functionally' acting brown adipocytes in white adipose tissue (WAT) has been identified as well: the so-called process of the 'browning' of WAT. While the importance of uncoupling protein 1 (UCP1)-oriented mitochondrial activation has been intensely studied, the role of peroxisomes during the browning of white adipocytes is poorly understood. Here, we assess the change in peroxisomal membrane proteins, or peroxins (PEXs), during cold stimulation and importantly, the role of PEX13 in the cold-induced remodeling of white adipocytes. PEX13, a protein that originally functions as a docking factor and is involved in protein import into peroxisome matrix, was highly increased during cold-induced recruitment of beige adipocytes within the inguinal WAT of C57BL/6 mice. Moreover, beige-induced 3 T3-L1 adipocytes and stromal vascular fraction (SVF) cells by exposure to the peroxisome proliferator-activated receptor gamma (PPARγ) agonist rosiglitazone showed a significant increase in mitochondrial thermogenic factors along with peroxisomal proteins including PEX13, and these were confirmed in SVF cells with the beta 3 adrenergic receptor (β3AR)-selective agonist CL316,243. To verify the relevance of PEX13, we used the RNA silencing method targeting the Pex13 gene and evaluated the subsequent beige development in SVF cells. Interestingly, siPex13 treatment suppressed expression of thermogenic proteins such as UCP1 and PPARγ coactivator 1 alpha (PGC1α). Overall, our data provide evidence supporting the role of peroxisomal proteins, in particular PEX13, during beige remodeling of white adipocytes., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Nutritional insults early in life have been associated with metabolic diseases in adulthood. We aimed to evaluate the effects of maternal food restriction during the suckling period on metabolism and interscapular brown adipose tissue (iBAT) thermogenically involved proteins in adult rat offspring. Wistar rats underwent food restriction by 50% during the first two-thirds of lactation (FR50 group). Control rats were fed ad libitum throughout lactation (CONT group). At birth, the litter size was adjusted to eight pups, and weaning was performed at 22 days old. Body weight and food and water intake were assessed every two days. High- (HCD, 4,589 cal) and normal-caloric diet (NCD, 3,860 cal) preferences, as well as food intake during the dark part of the cycle, were assessed. At 100 days old, the rats were euthanized, and blood and tissues were removed for further analyses. Adult FR50 rats, although hyperphagic and preferring to eat HCD (P<.001), were leaner (P<.001) than the CONT group. The FR50 rats, were normoglycemic (P=.962) and had hypertriglyceridemia (P<.01). In addition, the FR50 rats were dyslipidemic (P<.01), presenting with a high atherogenic risk by the Castelli indexes (P<.01), had a higher iBAT mass (P<.01), fewer β 3 adrenergic receptors (β 3 -AR, P<.05) and higher iBAT expression of uncoupled protein 1 (UCP1, P<.05) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α, P<.001) than the CONT rats. In conclusion, maternal food restriction during early breastfeeding programs rat offspring to have a lean phenotype, despite hyperphagia, and increased iBAT UCP1 and PGC-1α protein expression., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Aims: Prednisone is a corticosteroid-derived drug which is widely used for its role in immunosuppression and treatment of lung disorders. The current study reports, for the first time, the critical role of prednisone in the induction of white fat browning, thereby promoting thermogenic effect in cultured white adipocytes., Main Methods: The fat-browning activity of prednisone was evaluated in 3T3-L1 cells by quantitative real-time PCR, immunoblot analysis, immunofluorescence, and molecular docking techniques., Key Findings: Exposure to prednisone stimulated browning in 3T3-L1 white adipocytes by increasing the expressions of core fat browning marker proteins (UCP1, PGC-1α and PRDM16) as well as beige-specific genes (Cd137, Cidea, Cited1, and Tbx1) via ATF2 and CREB activation mediated by p38 MAPK and ERK signaling, respectively. Prednisone exposure also resulted in the robust activation of lipolytic and fatty acid oxidation marker proteins, thereby increasing mitochondrial biogenesis. In addition, prednisone treatment resulted in reduced expression levels of adipogenic transcription factors while elevating SIRT1, as well as attenuation of lipogenesis and lipid droplets formation. Furthermore, molecular docking and mechanistic studies demonstrated the recruitment of beige fat by prednisone via the β3-AR/p38 MAPK/ERK signaling pathway., Significance: Taken together, these results indicate the unique role of prednisone as a fat-browning stimulant, and demonstrate its therapeutic potential in the treatment of obesity by enhancing thermogenesis., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Aldosterone exerts deleterious effects on the cardiovascular system and promotes adipose tissue expansion via mineralocorticoid receptor (MR) activation. We previously demonstrated that administration of steroidal mineralocorticoid receptor antagonists (MRA) in mice fed a moderate high-fat diet is able to reduce white adipose tissue (WAT) expansion, stimulate browning of WAT and activate interscapular brown adipose tissue (iBAT). Here, we aimed to compare the metabolic and adipose tissue-specific effects of the novel non-steroidal MRA finerenone (Fine) and spironolactone (Spiro) in a mouse model of very high-fat diet (HFD)-induced obesity. C57BL/6 J male mice were fed a 60% HFD containing or not Spiro or Fine for 12 weeks. WAT and iBAT morphology and adipose tissue gene expression analysis were assessed. After 12 weeks, both groups of mice showed similar weight gain compared to the HFD group. Histological and molecular analyses of WAT did not show significant differences among all experimental groups; differently, iBAT histological analysis revealed that Fine was able to increase recruitment of brown adipocytes in this depot, whereas mice treated with Spiro failed to elicit any iBAT response, as indicated by no changes in lipid droplets size and iBAT density, compared to HFD. Increased iBAT recruitment could explain, at least in part, the improved insulin resistance observed in mice treated with Fine, as shown by a significant reduction in homeostasis model assessment of insulin resistance (HOMA) index. These findings were confirmed by gene expression analysis of ucp-1, pgc1-α, and beta-3 adrenoreceptor (Adrb3) in iBAT, revealing significantly higher expression of these thermogenic genes in HFD + Fine group compared to HFD, whereas Spiro did not modify their expression. In summary, we demonstrated that, differently from Fine, Spiro did not induce iBAT recruitment. Our current study suggests that Fine, through its direct effects on iBAT, represents a promising pharmacologic tool to treat human metabolic diseases associated with adipose tissue dysfunctions., (© 2021. Italian Society of Endocrinology (SIE).)

Manipulation of energy-dissipating adipocytes has the potential to produce metabolic benefits. To this end, it is valuable to understand the mechanisms controlling the generation and function of thermogenic fat. Here, we identify Letm1 domain containing 1 (Letmd1) as a regulator of brown fat formation and function. The expression of Letmd1 is induced in brown fat by cold exposure and by β-adrenergic activation. Letmd1-deficient mice exhibit severe cold intolerance concomitant with abnormal brown fat morphology, reduced thermogenic gene expression, and low mitochondrial content. The null mice exhibit impaired β3-adrenoreceptor-dependent thermogenesis and are prone to diet-induced obesity and defective glucose disposal. Letmd1 was previously described as a mitochondrial protein, and we find that it also localizes to the nucleus and interacts with the transcriptional coregulator and chromatin remodeler Brg1/Smarca4, thus providing a way to impact thermogenic gene expression. Our study uncovers a role for Letmd1 as a key regulatory component of adaptive thermogenesis., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Beta-3 adrenergic receptor activation via exercise or CL316,243 (CL) induces white adipose tissue (WAT) browning, improves glucose tolerance, and reduces visceral adiposity. Our aim was to determine if sex or adipose tissue depot differences exist in response to CL. Daily CL injections were administered to diet-induced obese male and female mice for two weeks, creating four groups: male control, male CL, female control, and female CL. These groups were compared to determine the main and interaction effects of sex (S), CL treatment (T), and WAT depot (D). Glucose tolerance, body composition, and energy intake and expenditure were assessed, along with perigonadal (PGAT) and subcutaneous (SQAT) WAT gene and protein expression. CL consistently improved glucose tolerance and body composition. Female PGAT had greater protein expression of the mitochondrial uncoupling protein 1 (UCP1), while SQAT (S, p < 0.001) was more responsive to CL in increasing UCP1 (S×T, p = 0.011) and the mitochondrial biogenesis induction protein, PPARγ coactivator 1α (PGC1α) (S×T, p = 0.026). Females also displayed greater mitochondrial OXPHOS (S, p < 0.05) and adiponectin protein content (S, p < 0.05). On the other hand, male SQAT was more responsive to CL in increasing protein levels of PGC1α (S×T, p = 0.046) and adiponectin (S, p < 0.05). In both depots and in both sexes, CL significantly increased estrogen receptor beta (ERβ) and glucose-related protein 75 (GRP75) protein content (T, p < 0.05). Thus, CL improves systemic and adipose tissue-specific metabolism in both sexes; however, sex differences exist in the WAT-specific effects of CL. Furthermore, across sexes and depots, CL affects estrogen signaling by upregulating ERβ.

Aim: To identify associations among allelic variants of the genes FTO, ABCA1, ADRB3, and PPARG with anthropometric and biochemical traits, metabolic diseases (obesity, T2D or metabolic syndrome) in an adult population from Northwest Mexico., Methods: Blood samples were collected from 846 subjects including 266 normal weight subjects, 285 with obesity, and 295 with T2D. Of the 846 persons in the study, 365 presented metabolic syndrome diagnostic criteria. Anthropometric and biochemical traits were recorded and 4 single nucleotide polymorphisms (SNPs): FTO rs9939609 A-allele, ABCA1 rs9282541 A-allele, ADRB3 rs4994 G-allele, and PPARG rs1801282 G-allele were genotyped by real-time PCR., Results: FTO rs9939609 A-allele was significantly associated with obesity (p: 8.3 × 10 -4 ), and metabolic syndrome (p: 0.001), but no individual SNPs were significantly associated with T2D. Finally, the cumulative risk of the four SNPs was significantly associated with obesity (p: 1.95 × 10 -4 )., Conclusion: Associations in FTO, ABCA, ADRB3, and PPARG SNPs presented in this study with obesity and metabolic syndrome could represent a risk for developing metabolic diseases in Northwest Mexican adult subjects., (Copyright © 2021. Published by Elsevier Inc.)

Cardiac pressure overload is a crucial risk factor for cardiac hypertrophy and heart failure. Our previous study showed that depletion of the β3-adrenergic receptor (ADRB3) induced left ventricular diastolic dysfunction via potential regulation of energy metabolism and cardiac contraction. However, the effects of ADRB3 on pressure overload-induced heart failure remain unclear. In the present study, systemic ADRB3-knockout mice suffering from transverse aortic constriction (TAC) surgery were used to identify the effects of ADRB3 on pressure overload-induced heart failure. Compared to wild-type mice, ADRB3 depletion significantly improved the left ventricular ejection fraction, reduced left ventricular posterior wall thickness and interventricular septum thickness, and decreased the area of cardiomyocytes after TAC. RNA sequencing and bioinformatics analysis showed that ADRB3 depletion up-regulated 275 mRNAs and down-regulated 105 mRNAs in mice suffering TAC surgery. GO analysis, GO-tree analysis, and GSEA showed that ADRB3 depletion mainly enhanced the innate immune response of hearts in cardiac pressure overload mice. In addition, pathway analysis and Pathway-Act analysis presented that innate immune response-related pathways, including RIG-I-like receptor signaling pathway, antigen processing and presentation, Toll-like receptor signaling pathway, and cell adhesion molecules, were significantly enriched in ADRB3-KO-TAC mice. Ten hub genes were identified using protein-protein interaction network, MCODE, and cytoHubba analysis. Furthermore, the depletion and activation of ADRB3 validated the effects of ADRB3 on the innate immune response of hearts after TAC. In conclusion, ADRB3 depletion relieves pressure overload-induced cardiac hypertrophy and heart failure, and these effects could be explained by the enhancement of innate immune response., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Increased browning of white adipocytes (beiging) is considered a promising therapeutic strategy to fight obesity and its associated metabolic complications. However, the molecular mechanism modulating brown and beige fat-mediated thermogenesis is not fully elucidated. Here, we identified the lymphocyte cytosolic protein 1 (LCP1) as a factor that obstructs fat browning in white adipocytes. LCP1 plays a vital role in non-hematopoietic malignancies, and is also a well-known tumor biomarker; however, evidence regarding its function in adipocytes remains to be elucidated. The current study explores the physiological role of LCP1 in cultured 3T3-L1 white adipocytes, by applying the loss-of-function study using siRNA. Induction of fat browning by LCP1 depletion was evidenced by evaluating the gene and protein expression levels of brown fat-associated markers through real-time qRT-PCR and immunoblot analysis, respectively. We observed that deficiency of LCP1 promotes mitochondrial biogenesis, and significantly enhances expressions of the core brown fat-specific genes (Cd137, Cidea, Cited1, Tbx1, and Tmem26) and proteins (PGC-1α, PRDM16, and UCP1). In addition, deficiency of LCP1 promotes lipid catabolism as well as suppresses adipogenesis and lipogenesis. Loss of LCP1 also ameliorates cellular stress by downregulating JNK and c-JUN in adipocytes, and stimulates apoptosis. A mechanistic study revealed that deficiency of LCP1 induces browning in white adipocytes, independently via β3-AR and the ERK signaling pathway. The current data reveals a previously unknown mechanism of LCP1 in browning of white adipocytes, and highlights the potential of LCP1 as a pharmacotherapeutic target for treating obesity and other metabolic disorders., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: The β 3 -adrenergic receptor (ADRB3) is very important in the regulation of the human detrusor muscle function. The well-known tryptophan64arginine polymorphism of the ADRB3 gene alters the response of the receptor to various stimuli, including adrenalin and noradrenalin, and may increase the susceptibility to develop overactive bladder (OAB). Therefore, this study was performed to determine whether ADRB3 Trp64Arg polymorphism is associated with the pathophysiology of OAB syndrome., Methods: The study group (n = 150) consists of 72 patients with OAB and 78 controls without OAB. Venous blood samples were taken from all participants to analyze the ADRB3 gene Trp64Arg polymorphism using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay. We compared the distribution of Trp64Arg polymorphism and symptom severity in both OAB and non-OAB subjects using χ 2 test and Mann-Whitney's U test, respectively., Results: The frequency of the 64Arg variant (heterozygous plus homozygous) in OAB and non-OAB subjects was 15.3% and 14.1%, respectively. There was no statistically significant difference between the OAB and non-OAB groups in regard to the distribution frequency of ADRB3 Trp64Arg polymorphism. The total frequency (OAB + non-OAB, 76 women and 74 men) of the Arg64 variant allele was 5.9% and 10.8% in women and in men, respectively. Although the frequency of the Arg64 variant was nearly twofold higher in men compared to women, the difference was not statistically significant., Conclusions: These results demonstrated that the ADRB3 Trp64Arg polymorphism is not significantly associated with OAB syndrome in a sample of Turkish OAB patients., (© 2021 Wiley Periodicals LLC.)