UCP2 mRNA Levels Research Articles

Irisin promotes the browning of white adipocytes tissue by AMPKα1 signaling pathway

The development of white adipose tissue (WAT) browning helps to protect animals from cold conditions and prevent obesity. AMPKα1 has been involved in the process of white adipocytes browning. Although Irisin plays a vital role in the browning of WAT, the detailed regulatory mechanism of Irisin inducing the browning of WAT remains unclear. Herein, we firstly investigated the potential roles of differentiation and Irisin in regulating the browning of 3T3-L1 cells. The results found that they could significantly increase the number of lipid droplets and upregulate the expression levels of UCP1, PGC-1α, PRDM16, and p-AMPKα1. Then we proved the effectiveness of the AMPKα1 signaling pathway in the process of Irisin inducing the browning of 3T3-L1 cells. Compared with si-NC, si-AMPKα1 not only decreased the number of Irisin-induced lipid droplets, but also attenuated the expression of Irisin-induced UCP1, PGC-1α, and PRDM16 protein and mRNA levels in 3T3-L1 cells. Furthermore, the results showed that Irisin increased the positive distribution of UCP1 and PGC-1α, and upregulated the expression of UCP1, PGC-1α, and PRDM16 at both protein and mRNA levels in WAT. Once siRNA treated mice, the facilitation of Irisin on UCP1 and PGC-1α in si-AMPKα1-injected mice was lower than that in si-NC-injected mice. Compared with si-NC, si-AMPKα1 significantly downregulated the expression of UCP1, PGC-1α, and PRDM16 in Irisin-injected mice. Taken together, our results demonstrate that Irisin activates the AMPKα1 pathway to promote the browning of WAT by upregulating the mRNA and protein levels of UCP1, PGC-1α, and PRDM16.

Browning Subcutaneous White Adipose Tissue Using Transdermal Delivery of ASC-Targeting Peptide and Resveratrol Conjugate

Objectives Trans-resveratrol (RES) can significantly enhance the browning of subcutaneous white adipose tissue (WAT) when delivered to adipose stromal stem cells (ASCs) in WAT, the precursors of beige adipocytes. ASC-targeting peptide (GSWKYWFGEGGC) and RES have been conjugated using succinyl as a linker. The objective of this study is to transdermally deliver ASC-targeting peptide-RES conjugate directly to subcutaneous WAT using microneedle (MN) and iontophoresis (INT) and validate their browning and anti-obesity efficacy in obese mice.MethodsDissolving MN patches were developed using carboxymethylcellulose (CMC). Delivery effectiveness of MN was determined by an in vivo fluorescence imaging after applying dye-loaded MN on the skin above inguinal WAT (iWAT) in mice. Peptide-RES conjugate was loaded into CMC MN that was applied on the skins above iWAT of mice. After MN were dissolved, INT patch was applied to enhance penetration. Male C57BL/6J mice (5/group) were fed ahigh fat diet for 9 weeks. After 4 weeks of the high fat diet, mice were randomly divided into 3 groups as 1. MN (Blank)+INT, 2. MN (free RES)+INT, and 3. MN (peptide-RES conjugate) +INT. Mice received treatments 2 times/week from week 5 to 9. Food intake, body weight, and body composition were measured weekly, and the glucose tolerance test was conducted at week 9.ResultsMN (dye)+INT-treated mice had 2-fold higher dye signals in iWAT as compared to mice treated with MN alone. Dye signals in other organs/tissues were too low to be detected indicating the success of local (MN + INT) delivery and less diffusion. After 5 weeks of treatment, mice treated with MN (peptide-RES conjugate)+INT as compared to other two groups of mice had more than 1.5-fold lower body weight and fat%, 1.4-fold lower blood glucose levels, and more than 3-fold iWAT mRNA levels of UCP1 indicating browning of iWAT.ConclusionsTransdermal delivery of ASC-targeting peptide-RES conjugate to iWAT induces browning of subcutaneous WAT, resulting in body weight and fat loss in obese mice. Transdermal delivery might provide an innovative and efficient approach for combating obesity and its comorbidities.Funding SourcesNIH 1R15AT010395-01 and American Heart Association 19AIREA34480011.

Brown adipocytes promote epithelial mesenchymal transition of neuroblastoma cells by inducing PPAR-γ/UCP2 expression

ABSTRACT Neuroblastoma (NB) is an embryonic malignant tumour of the sympathetic nervous system, and current research shows that activation of brown adipose tissue accelerates cachexia in cancer patients. However, the interaction between brown adipose tissues and NB remains unclear. The study aimed to investigate the effect of brown adipocytes in the co-culture system on the proliferation and migration of NB cells. Brown adipocytes promoted the proliferation and migration of Neuro-2a, BE(2)-M17, and SH-SY5Y cells under the co-culture system, with an increase of the mRNA and protein levels of UCP2 and PPAR-γ in NB cells. The UCP2 inhibitor genipin or PPAR-γ inhibitor T0090709 inhibited the migration of NB cells induced by brown adipocytes. Genipin or siUCP2 upregulated the expression of E-cadherin, and downregulated the expression of N-cadherin and vimentin in NB cells. We suggest that under co-cultivation conditions, NB cells can activate brown adipocytes, which triggers changes in various genes and promotes the proliferation and migration of NB cells. The PPAR-γ/UCP2 pathway is involved in the migration of NB cells caused by brown adipocytes.

Maternal Consumption of a Cafeteria Diet during Lactation Leads to Altered Diet-Induced Thermogenesis in Descendants after Exposure to a Western Diet in Adulthood.

This study investigates the ability of a maternal cafeteria diet during lactation to program brown adipose tissue (BAT) metabolic responses to an obesogenic diet re-exposure in the adult offspring after consuming a standard diet (SD). Nursing rats were fed an SD or a cafeteria diet during lactation. Their offspring (O-C and O-CAF, respectively) were weaned onto an SD, and at 16 weeks of age they were switched to a Western diet until week 24. Gene and protein expression in BAT were measured at PN22 and at 24 weeks. At PN22, compared to controls, O-CAF rats displayed lower mRNA levels of lipogenesis-related genes (Fasn), and higher expression of genes related to lipolysis (Pnpla2), fatty acid uptake (Cd36, Lpl), and oxidation (Cpt1b). Additionally, O-CAF animals displayed increased mRNA levels of Adrb3, Ucp1, and Cidea. In adulthood, these animals maintained lower mRNA levels of lipogenesis-related genes (Pparg, Srebf1, Fasn), but displayed lower expression of genes related to fatty acid uptake (Cd36), fatty acid oxidation (Cpt1b), lipolysis (Pnpla2), Adrb3, Ucp1, and Cidea. Thus, exposure to an obesogenic diet in nursing rats can affect long-term lipid metabolism and attenuate diet-induced thermogenesis in BAT in response to a new obesogenic dietary challenge later in life.

Evaluation of Browning Markers in Subcutaneous Adipose Tissue of Newly Diagnosed Gastrointestinal Cancer Patients with and without Cachexia.

Simple SummaryCachexia occurs frequently in cancer patients with deep metabolic derangements. The browning of adipose tissue promotes thermogenesis and energy expenditure and, in cancer, has been considered a major determinant of adipose tissue atrophy. We evaluated the molecular phenotype of this phenomenon in the subcutaneous adipose tissue (SAT) of newly diagnosed gastrointestinal cancer patients compared to controls. We observed that the modulation of different markers of the browning of SAT in gastrointestinal cancer and, in particular, pancreatic cancer showed significant changes in UCP1 and PGC1α; PGC1α was highly expressed in cachectic patients. Our study highlights the relevance of browning in patients with cancer, in particular in those with pancreatic cancer. Understanding the browning phenomenon may allow us to counteract these metabolic alterations before the development of severe cachexia, which is characterized by deep adipose and muscle depletion, negatively affecting survival and quality of life.We assessed the molecular phenotype of the browning of white adipose tissue in newly diagnosed cancer patients and controls undergoing surgery for gastrointestinal tumors and for non-malignant diseases, respectively. We collected subcutaneous adipose tissue (SAT) samples and using RT-PCR, we analyzed the expression of markers of browning and using Western blot the protein levels of UCP1 and PGC1α. The Ucp1 mRNA levels were lower in cancer patients vs. controls (p = 0.01), whereas Cidea and Tmem26 mRNA levels were higher in cancer patients. We found higher PGC1α protein levels in patients vs. controls, while no differences were seen for UCP1. The Ucp1 expression was lower in cachectic and non-cachectic patients vs. controls, whereas Cidea expression was higher in cachectic and non-cachectic patients vs. controls. Pgc1α mRNA levels were higher in cachectic vs. non-cachectic patients (p = 0.03) vs. controls (p = 0.016). According to type of tumors, we did not observe differences in Cidea expression, whereas Pgc1α was higher in pancreatic cancer vs. colorectal and vs. controls. We observed the lower expression of Ucp1 in pancreatic and colorectal cancer vs. controls. We documented higher UCP1 protein levels in pancreatic cancer patients vs. colorectal (p = 0.002) and vs. controls (p = 0.031). PGC1α protein levels were higher in pancreatic cancer patients vs. controls. Different markers of the browning of SAT are modulated, and pancreatic cancer showed changes in UCP1 and PGC1α; PGC1α was highly expressed in cachectic patients, with clinical implications that should be further clarified.

MiR-27b inhibition contributes to cytotoxicity in patulin-exposed HEK293 cells

Patulin (PAT) is a mycotoxin produced by Penicillium and other fungi that contaminate fruit. PAT targets the kidney and is associated with nephrotoxicity. Micro-RNAs (miRNA) may offer new insights into PAT-induced nephrotoxicity. Cytochrome P450 family 1, subfamily B, polypeptide 1 (CYP1B1), involved in metabolism of dietary toxins is negatively regulated by miR-27b and linked with the nuclear factor kappa B (NF-κB) pathway and peroxisome proliferator activated receptor gamma (PPARɣ) in renal fibrosis. This study investigated the effects of PAT on miR-27b, CYP1B1, PPARɣ and cytotoxicity in human kidney (HEK293) cells.HEK293 cells were exposed to PAT (2.5 μM, 24h). Protein expression of CYP1B1, PPARɣ, NF-κB (p65), pNF-κB (p65) (phospho-Ser563) and cleaved PARP-1 was quantified using western blotting. QPCR evaluated mRNA levels of CYP1B1, IL-6, miR-27b, OGG1, mtDNA, TFAM and UCP2. Mitochondrial membrane potential and phosphatidylserine (PS) externalization was evaluated by flow cytometry while levels of ATP and caspase −9, −8, −3/7 activity was measured using luminometry.PAT significantly decreased miR-27b levels (p = 0.0014) and increased CYP1B1 mRNA (p = 0.0015) and protein (p = 0.0013) levels. PPARɣ protein expression was significantly increased (p = 0.0002) and associated with decreased NF-κB activation (p = 0.0273) and IL-6 mRNA levels (p = 0.0265). Finally, PAT significantly compromised mitochondrial repair mechanisms and increased apoptotic biomarkers.PAT altered miR-27b levels and PPARɣ, with associated changes to NF-κB activation, downstream IL-6 and CYP1B1 expression. These results show that PAT impairs detoxification mechanisms leading to mitochondrial damage and apoptosis. In conclusion, PAT altered the epigenetic environment and impaired detoxification processes, supporting a mechanism for nephrotoxic outcomes.

Specific adipose tissue Lbp gene knockdown prevents diet-induced body weight gain, impacting fat accretion-related gene and protein expression

Lipopolysaccharide binding protein (Lbp) has been recently identified as a relevant component of innate immunity response associated to adiposity. Here, we aimed to investigate the impact of adipose tissue Lbp on weight gain and white adipose tissue (WAT) in male and female mice fed an obesogenic diet. Specific adipose tissue Lbp gene knockdown was achieved through lentiviral particles containing shRNA-Lbp injected through surgery intervention. In males, WAT Lbp mRNA levels increased in parallel to fat accretion, and specific WAT Lbp gene knockdown led to reduced body weight gain, decreased fat accretion-related gene and protein expression, and increased inguinal WAT basal lipase activity, in parallel to lowered plasma free fatty acids, leptin, triglycerides but higher glycerol levels, resulting in slightly improved insulin action in the insulin tolerance test. In both males and females, inguinal WAT Lbp gene knockdown resulted in increased Ucp1 and Ppargc1a mRNA and Ucp1 protein levels, confirming adipose Lbp as a WAT browning repressor. In perigonadal WAT, Lbp gene knockdown also resulted in increased Ucp1 mRNA levels, but only in female mice, in which it was 500-fold increased. These data suggest specific adipose tissue Lbp gene knockdown as a possible therapeutic approach in the prevention of obesity-associated fat accretion.

Apple Polyphenols Extracts Ameliorate High Carbohydrate Diet-Induced Body Weight Gain by Regulating the Gut Microbiota and Appetite.

To investigate the potential contribution of appetite regulation and modulation of gut microbiota to the ameliorated effects of apple polyphenols extracts (APE) on high carbohydrate diet (HCD)-induced body weight (BW) gain, we conducted this study. One hundred C57BL/6 male mice were randomly divided into seven groups and fed with the following diets for 12 weeks: chow diet (CON), HCD (HCD), high fructose and sucrose diet (HSCD), and HCD and HSCD with 125 or 500 mg/kg·day APE gavage. Compared to the CON group, the BW of mice in the HCD and HSCD groups increased significantly. HSCD induced a more significant weight gain in the white adipose tissue (WAT) and liver than HCD, accompanied by severe impairment of glucose tolerance and a larger diameter of adipocytes. On the other hand, by decreasing food intake, APE significantly reduced BW via mechanisms, including decreased weights of the WAT and liver, amelioration of glucose tolerance, and amplification of WAT browning by upregulating the mRNA levels of Ucp-1 and Cidea. Moreover, APE promoted transcription and secretion of GLP-1, with the increased expression of gut anorexigenic hormone peptides Ffar 2/3 in the colon and anorectic neuropeptide gene expression of Pomc, Cart, and Mc4r in the hypothalamus, causing increased satiety. Additionally, APE significantly increased Verrucomicrobia colonization and the relative abundance of Akkermansia. APE potentially ameliorates high simple carbohydrate diet-induced body weight gain by mechanisms related to gut microbiota regulation and appetite inhibition.

Wt1 haploinsufficiency induces browning of epididymal fat and alleviates metabolic dysfunction in mice on high-fat diet

Aims/hypothesisDespite a similar fat storing function, visceral (intra-abdominal) white adipose tissue (WAT) is detrimental, whereas subcutaneous WAT is considered to protect against metabolic disease. Recent findings indicate that thermogenic genes, expressed in brown adipose tissue (BAT), can be induced primarily in subcutaneous WAT. Here, we investigate the hypothesis that the Wilms tumour gene product (WT1), which is expressed in intra-abdominal WAT but not in subcutaneous WAT and BAT, suppresses a thermogenic program in white fat cells.MethodsHeterozygous Wt1 knockout mice and their wild-type littermates were examined in terms of thermogenic and adipocyte-selective gene expression. Glucose tolerance and hepatic lipid accumulation in these mice were assessed under normal chow and high-fat diet conditions. Pre-adipocytes isolated from the stromal vascular fraction of BAT were transduced with Wt1-expressing retrovirus, induced to differentiate and analysed for the expression of thermogenic and adipocyte-selective genes.ResultsExpression of the thermogenic genes Cpt1b and Tmem26 was enhanced and transcript levels of Ucp1 were on average more than tenfold higher in epididymal WAT of heterozygous Wt1 knockout mice compared with wild-type mice. Wt1 heterozygosity reduced epididymal WAT mass, improved whole-body glucose tolerance and alleviated severe hepatic steatosis upon diet-induced obesity in mice. Retroviral expression of WT1 in brown pre-adipocytes, which lack endogenous WT1, reduced mRNA levels of Ucp1, Ppargc1a, Cidea, Prdm16 and Cpt1b upon in vitro differentiation by 60–90%. WT1 knockdown in epididymal pre-adipocytes significantly lowered Aldh1a1 and Zfp423 transcripts, two key suppressors of the thermogenic program. Conversely, Aldh1a1 and Zfp423 mRNA levels were increased approximately five- and threefold, respectively, by retroviral expression of WT1 in brown pre-adipocytes.Conclusion/interpretationWT1 functions as a white adipocyte determination factor in epididymal WAT by suppressing thermogenic genes. Reducing Wt1 expression in this and other intra-abdominal fat depots may represent a novel treatment strategy in metabolic disease.Graphical abstract

Transcriptional response of key metabolic and stress response genes of a nuculanid bivalve, Lembulus bicuspidatus from an oxygen minimum zone exposed to hypoxia-reoxygenation.

Benthic animals inhabiting the edges of marine oxygen minimum zones (OMZ) are exposed to unpredictable large fluctuations of oxygen levels. Sessile organisms including bivalves must depend on physiological adaptations to withstand these conditions. However, as habitats are rather inaccessible, physiological adaptations of the OMZ margin inhabitants to oxygen fluctuations are not well understood. We therefore investigated the transcriptional responses of selected key genes involved in energy metabolism and stress protection in a dominant benthic species of the northern edge of the Namibian OMZ, the nuculanid clam Lembulus bicuspidatus,. We exposed clams to normoxia (~5.8ml O2 l-1), severe hypoxia (36h at ~0.01ml O2 l-1) and post-hypoxic recovery (24h of normoxia following 36h of severe hypoxia). Using newly identified gene sequences, we determined the transcriptional responses to hypoxia and reoxygenation of the mitochondrial aerobic energy metabolism (pyruvate dehydrogenase E1 complex, cytochrome c oxidase, citrate synthase, and adenine nucleotide translocator), anaerobic glycolysis (hexokinase (HK), phosphoenolpyruvate carboxykinase (PEPCK), phosphofructokinase, and aldolase), mitochondrial antioxidants (glutaredoxin, peroxiredoxin, and uncoupling protein UCP2) and stress protection mechanisms (a molecular chaperone HSP70 and a mitochondrial quality control protein MIEAP) in the gills and the labial palps of L. bicuspidatus. Exposure to severe hypoxia transcriptionally stimulated anaerobic glycolysis (including HK and PEPCK), antioxidant protection (UCP2), and quality control mechanisms (HSP70 and MIEAP) in the gills of L. bicuspidatus. Unlike UCP2, mRNA levels of the thiol-dependent mitochondrial antioxidants were not affected by hypoxia-reoxygenation stress. Transcript levels of marker genes for aerobic energy metabolism were not responsive to oxygen fluctuations in L. bicuspidatus. Our findings highlight the probable importance of anaerobic succinate production (via PEPCK) and mitochondrial and proteome quality control mechanisms in responses to oxygen fluctuations of the OMZ bivalve L.bicuspidatus. The reaction of L.bicuspidatus to oxygen fluctuations implies parallels to that of other hypoxia-tolerant bivalves, such as intertidal species.

On the Validity of Adipogenic Cell Lines as Model Systems for Browning Processes: In Authentic Brown, Brite/Beige, and White Preadipocytes, There is No Cell-Autonomous Thermogenic Recruitment by Green Tea Compounds.

The potential ability of nutritional compounds to induce or enhance the browning of adipocytes has attracted large interest as a workable means of combatting the obesity epidemic. Green tea compounds are discussed as such inducers of an enhanced thermogenic capacity and activity. However, the cell-autonomous effects of green tea compounds on adipocytes have until now only been demonstrated in adipogenic cell lines (3T3-L1 and 3T3-F442A), i.e., cells of undefined tissue lineage. In this study, we examine the ability of green tea compounds to cell-autonomously induce thermogenic recruitment in authentic brown and brite/beige adipocytes in vitro. In primary brown adipocytes, the green tea compounds suppressed basal UCP1 gene expression, and there was no positive interaction between the compounds and adrenergic stimulation. In white adipocytes, green tea compounds decreased both basal and norepinephrine-induced UCP1 mRNA levels, and this was associated with the suppression of cell differentiation, indicated by reduced lipogenic gene expression and lipid accumulation. A lack of interaction between rosiglitazone and green tea compounds suggests that the green tea compounds do not directly interact with the PPARγ pathway. We conclude that there is a negative effect of the green tea compounds on basal UCP1 gene expression, in both brown and white primary adipocytes, in contrast to the positive effects earlier reported from studies in adipogenic cell lines. We posit that the epigenetic status of the adipogenic cell lines is fundamentally different from that of genuine brown and white adipocytes, reflected, e.g., in several-thousand-fold differences in UCP1 gene expression levels. Thus, results obtained with adipogenic cell lines cannot unreservedly be extrapolated as being relevant for authentic effects in brown and white adipocytes. We suggest that this conclusion can be of general concern for studies attempting to establish physiologically relevant cell-autonomous effects.

Fish Oil Increases Diet-Induced Thermogenesis in Mice.

Increasing energy expenditure (EE) is beneficial for preventing obesity. Diet-induced thermogenesis (DIT) is one of the components of total EE. Therefore, increasing DIT is effective against obesity. We examined how much fish oil (FO) increased DIT by measuring absolute values of DIT in mice. C57BL/6J male mice were given diets of 30 energy% fat consisting of FO or safflower oil plus butter as control oil (Con). After administration for 9 days, respiration in mice was monitored, and then the data were used to calculate DIT and EE. DIT increased significantly by 1.2-fold in the FO-fed mice compared with the Con-fed mice. Body weight gain was significantly lower in the FO-fed mice. FO increased the levels of uncoupling protein 1 (Ucp1) mRNA and UCP1 protein in brown adipose tissue (BAT) by 1.5- and 1.2-fold, respectively. In subcutaneous white adipose tissue (subWAT), the levels of Ucp1 mRNA and UCP1 protein were increased by 6.3- and 2.7-fold, respectively, by FO administration. FO also significantly increased the expression of markers of browning in subWAT such as fibroblast growth factor 21 and cell death-inducing DNA fragmentation factor α-like effector a. Thus, dietary FO seems to increase DIT in mice via the increased expressions of Ucp1 in BAT and induced browning of subWAT. FO might be a promising dietary fat in the prevention of obesity by upregulation of energy metabolism.

트레드밀 운동이 난소 절제 쥐의 지질대사 조절인자 및 지방조직 갈색화에 미치는 영향

The purpose of this study was to investigate the effects of aerobic exercise training on lipid metabolism regulators and browning of adipose tissue in ovariectomized rats. A total 36 of female Sprague-Dawley rats were divided into three groups: CON (normal control, n=12), OVA-CON (ovariectomized-control), OVA-TE (ovariectomized + treadmill exercise, n=12). The rats in the OVA-TE group were forced to run a treadmill for 30 min 4 times per week for 12 weeks. In the liver, the mRNA levels of peroxisome proliferator-activated receptor-gamma (PPARγ) and SPEBP-1 were significantly decreased in the OVA-TE group compared with the OVA-CON group (p<.05). In the gastrocnemius, the PGC-1α mRNA expression was significantly increased in the OVA-TE group compared to the OVACON group(p<.05). Also, the OVA-CON group showed significantly decreased UCP-1 mRNA levels compared to the CON group, while the OVA-TE group was significantly higher than the OVA-CON group(p<.05). These results indicate that regular aerobic exercise could improve the lipid metabolism-related factors and enhance the browning of adipose tissue in the ovariectomized rats.

Untypical Metabolic Adaptations in Spontaneously Hypertensive Rats to Free Running Wheel Activity Includes Uncoupling Protein-3 (UCP-3) and Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Expression.

Obesity and hypertension are common risk factors for cardiovascular disease whereas an active lifestyle is considered as protective. However, the interaction between high physical activity and hypertension is less clear. Therefore, this study investigates the impact of high physical activity on the muscular and hepatic expression of glucose transporters (Glut), uncoupling proteins (UCPs), and proprotein convertase subtilisin/kexin type 9 (PCSK9) in spontaneously hypertensive rats (SHRs). Twenty-four female rats (12 normotensive rats and 12 SHRs) were divided into a sedentary control and an exercising group that had free access to running wheels at night for 10 months. Blood samples were taken and blood pressure was determined. The amount of visceral fat was semi-quantitatively analyzed and Musculus gastrocnemius, Musculus soleus, and the liver were excised. Acute effects of free running wheel activity were analyzed in 15 female SHRs that were sacrificed after 2 days of free running wheel activity. M. gastrocnemius and M. soleus differed in their mRNA expression of UCP-2, UCP-3, GLUT-4, and PCSK9. Hypertension was associated with lower levels of UCP-2 and PCSK9 mRNA in the M. gastrocnemius, but increased expression of GLUT-1 and GLUT-4 in the M. soleus. Exercise down-regulated UCP-3 in the M. soleus in both strains, in the M. gastrocnemius only in normotensives. In SHRs exercise downregulated the expression of UCP-2 in the M. soleus. Exercise increased the expression of GLUT-1 in the M. gastrocnemius in both strains, and that of GLUT-4 protein in the M. soleus, whereas it increased the muscle-specific expression of PCSK9 only in normotensive rats. Effects of exercise on the hepatic expression of cholesterol transporters were seen only in SHRs. As an acute response to exercise increased expressions of the myokine IL-6 and that of GLUT-1 were found in the muscles. This study, based on transcriptional adaptations in striated muscles and livers, shows that rats perform long-term metabolic adaptations when kept with increased physical activity. These adaptations are at least in part required to stabilize normal protein expression as protein turnover seems to be modified by exercise. However, normotensive and hypertensive rats differed in their responsiveness. Based on these results, a direct translation from normotensive to hypertensive rats is not possible. As genetic differences between normotensive humans and patients with essential hypertension are likely to be present as well, we would expect similar differences in humans that may impact recommendations for non-pharmacological interventions.

MK2-Deficient Mice Are Bradycardic and Display Delayed Hypertrophic Remodeling in Response to a Chronic Increase in Afterload.

BackgroundMitogen‐activated protein kinase–activated protein kinase‐2 (MK2) is a protein serine/threonine kinase activated by p38α/β. Herein, we examine the cardiac phenotype of pan MK2‐null (MK2−/−) mice.Methods and ResultsSurvival curves for male MK2+/+ and MK2−/− mice did not differ (Mantel‐Cox test, P=0.580). At 12 weeks of age, MK2−/− mice exhibited normal systolic function along with signs of possible early diastolic dysfunction; however, aging was not associated with an abnormal reduction in diastolic function. Both R‐R interval and P‐R segment durations were prolonged in MK2‐deficient mice. However, heart rates normalized when isolated hearts were perfused ex vivo in working mode. Ca2+ transients evoked by field stimulation or caffeine were similar in ventricular myocytes from MK2+/+ and MK2−/− mice. MK2−/− mice had lower body temperature and an age‐dependent reduction in body weight. mRNA levels of key metabolic genes, including Ppargc1a, Acadm, Lipe, and Ucp3, were increased in hearts from MK2−/− mice. For equivalent respiration rates, mitochondria from MK2−/− hearts showed a significant decrease in Ca2+ sensitivity to mitochondrial permeability transition pore opening. Eight weeks of pressure overload increased left ventricular mass in MK2+/+ and MK2−/− mice; however, after 2 weeks the increase was significant in MK2+/+ but not MK2−/− mice. Finally, the pressure overload–induced decrease in systolic function was attenuated in MK2−/− mice 2 weeks, but not 8 weeks, after constriction of the transverse aorta.ConclusionsCollectively, these results implicate MK2 in (1) autonomic regulation of heart rate, (2) cardiac mitochondrial function, and (3) the early stages of myocardial remodeling in response to chronic pressure overload.

The Effect of ω3 Fatty Acids Supplementation on Levels of PPARγ and UCP2 Genes Expression, Serum Level of UCP2 Protein, Metabolic Status, and Appetite in Elite male Athletes: Protocol for a Randomized Control Trial.

Some genetic factors may influence body composition, such as PPARγ and UCP2. PPARγ plays an important role in body fat distribution. The objective of the present study is to determine the effects of omega3 fatty acids on the gene expression of PPARγ and UCP2, levels of blood lipid profile, fat mass, and fat-free mass, and appetite.Elite male athlete volunteers of up to 36 subjects were invited to participate in this RCT. Following a public announcement, volunteers were recruited from gyms, teams, and sports medicine boards in Tabriz, Iran. Gene’s expression of PPARγ and UCP2, serum levels of blood lipid profile, fat mass, and fat-free mass was collected. Data collection time points include baseline in addition to 3 weeks follow up. The study was approved by the Ethics Committee of the Tabriz University Medical of Sciences (IR.TBZMED.REC.1398.782) in October 2019 and was registered with the Iranian Registry of Clinical Trials: 20190625044008N1 on December 19, 2019.Recruitment began in July and concluded in December 2019. As of August 19, 2019, we have screened 373 volunteers. 36 were enrolled. Baseline measurements of participants were collected. After three-week of intervention, end study measurements of participants were collected. The results are expected to be released in 2021. Participants have a median age of 21.86 (±3.15). The finding of this study showed Results showed PPARγ mRNA levels, and UCP2 mRNA and protein levels increased in the omega3 group (p < 0.05), as did REE (p < 0.05). Also, differences in the sensation of hunger or satiety were significant (p < 0.05).This study could result in the effects of omega-3 fatty acids on PPARγ, and UCP2 expressions, blood lipid profiles and body composition. In addition, the results of this trial can be used as baseline information for conducting further clinical and sport nutrition studies.Trial Registration:The trial was registered at the Iranian registry of the clinical trial website (www.irct.ir) as IRCT20190625044008N1 (https://en.irct.ir/trial/43332), registered at (19/12/2019).HighlightsOmega3 fatty acids as a ligand of metabolic-related genes, have a role in energy expenditure.Omega3 supplements effect on PPARγ and UCP2 mRNA expression as regulators of energy metabolismOmega3 supplements increased REE.Omega-3 supplementation could change the changes in body composition.For athletes, omega-3 simultaneously decreased fat mass and increased fat-mass.HDL-C increased after short-term supplementation with omega-3.Increased intake of omega-3, caused increased intake of energy and protein.

Thermogenic recruitment of brown and brite/beige adipose tissues is not obligatorily associated with macrophage accretion or attrition.

Cold- and diet-induced recruitment of brown adipose tissue (BAT) and the browning of white adipose tissue (WAT) are dynamic processes, and the recruited state attained is a state of dynamic equilibrium, demanding continuous stimulation to be maintained. An involvement of macrophages, classical proinflammatory (M1) or alternatively activated anti-inflammatory (M2), is presently discussed as being an integral part of these processes. If these macrophages play a mediatory role in the recruitment process, such an involvement would have to be maintained in the recruited state. We have, therefore, investigated whether the recruited state of these tissues is associated with macrophage accretion or attrition. We found no correlation (positive or negative) between total UCP1 mRNA levels (as a measure of recruitment) and proinflammatory macrophages in any adipose depot. We found that in young chow-fed mice, cold-induced recruitment correlated with accretion of anti-inflammatory macrophages; however, such a correlation was not seen when cold-induced recruitment was studied in diet-induced obese mice. Furthermore, the anti-inflammatory macrophage accretion was mediated via β1/β2-adrenergic receptors; yet, in their absence, and thus in the absence of macrophage accretion, recruitment proceeded normally. We thus conclude that the classical recruited state in BAT and inguinal (brite/beige) WAT is not paralleled by macrophage accretion or attrition. Our results make mediatory roles for macrophages in the recruitment process less likely.NEW & NOTEWORTHY A regulatory or mediatory role-positive or negative-for macrophages in the recruitment of brown adipose tissue is presently discussed. As the recruited state in the tissue is a dynamic process, maintenance of the recruited state would need persistent alterations in macrophage complement. Contrary to this expectation, we demonstrate here an absence of alterations in macrophage complement in thermogenically recruited brown-or brite/beige-adipose tissues. Macrophage regulation of thermogenic capacity is thus less likely.

Ad36 promotes differentiation of hADSCs into brown adipocytes by up-regulating LncRNA ROR

AimsThis study is to investigate the role of adenovirus type 36 (Ad36) in inducing differentiation of human adipose-derived stem cells (hADSCs) into brown adipocytes. Main methodsThe hADSCs were induced to differentiate into adipocytes by a cocktail method and Ad36, respectively. They were collected on the 2nd, 4th, 6th, and 8th day, respectively. LncRNA ROR was silenced by siRNA. RT-qPCR and Western-blot were used to detect the mRNA and protein levels. Transmission electron microscopy was used to observe the mitochondria. Key findingsThe mRNA and protein expression levels of LncRNA ROR, Cidea, Dio2, Fgf21, Ucp1, Prdm16, Cox5b, Atp5o, Atp6, and Nd2 in the Ad36 induction group were significantly higher than those in the cocktail induction group. The expression levels of Leptin mRNA and protein in the Ad36 induction group were significantly lower than those in the cocktail induction group. After siRNA knockdown of LncRNA ROR, mRNA and protein expression levels of Cidea, Dio2, Fgf21, Ucp1, Prdm16, Cox5b, Atp5o, Atp6 and Nd2 were significantly lower than the control group during the induction of hADSC differentiation into adipocytes by Ad36. Additionally, mitochondria in the Ad36 induction group was increased compared to that in the cocktail induction group. SignificanceAd36 may promote the differentiation of hADSCs into brown adipocytes by up-regulating LncRNA ROR.

Ghrelin in the lateral parabrachial nucleus influences the excitability of glucosensing neurons, increases food intake and body weight.

Ghrelin plays a pivotal role in the regulation of food intake, body weight and energy metabolism. However, these effects of ghrelin in the lateral parabrachial nucleus (LPBN) are unexplored. C57BL/6J mice and GHSR−/− mice were implanted with cannula above the right LPBN and ghrelin was microinjected via the cannula to investigate effect of ghrelin in the LPBN. In vivo electrophysiological technique was used to record LPBN glucose-sensitive neurons to explore potential udnderlying mechanisms. Microinjection of ghrelin in LPBN significantly increased food intake in the first 3 h, while such effect was blocked by [D-Lys3]-GHRP-6 and abolished in GHSR−/− mice. LPBN ghrelin microinjection also significantly increased the firing rate of glucose-excited (GE) neurons and decreased the firing rate of glucose-inhibited (GI) neurons. Additionally, LPBN ghrelin microinjection also significantly increased c-fos expression. Chronic ghrelin administration in the LPBN resulted in significantly increased body weight gain. Meanwhile, no significant changes were observed in both mRNA and protein expression levels of UCP-1 in BAT. These results demonstrated that microinjection of ghrelin in LPBN could increase food intake through the interaction with growth hormone secretagogue receptor (GHSR) in C57BL/6J mice, and its chronic administration could also increase body weight gain. These effects might be associated with altered firing rate in the GE and GI neurons.

Regulatory expression of uncoupling protein 1 and its related genes by endogenous activity of the transforming growth factor-β family in bovine myogenic cells.

Uncoupling protein 1 (UCP1) is responsible for non-shivering thermogenesis, with restricted expression in brown/beige adipocytes in humans and rodents. We have previously shown an unexpected expression of UCP1 in bovine skeletal muscles. This study evaluated factors affecting Ucp1 gene expression in cultured bovine myogenic cells. Myosatellite cells, which were isolated from the bovine musculus longissimus cervicis, were induced to differentiate into myotubes in the presence of 2% horse serum. Previous studies using murine brown/beige adipocytes revealed that Ucp1 expression levels are directly increased by forskolin and all-trans retinoic acid (RA). The transforming growth factor-β (TGF-β)/activin pathway negatively regulated Ucp1 expression, whereas activation of the bone morphogenetic protein (BMP) pathway indirectly increases Ucp1 expression through the stimulation of brown/beige adipogenesis. Neither forskolin nor RA significantly affected Ucp1 mRNA levels in bovine myogenic cells. A-83-01, an inhibitor of the TGF-β/activin pathway, stimulated myogenesis in these cells. A-83-01 significantly increased the expression of some brown fat signature genes such as Pgc-1α, Cox7a1, and Dio2, with a quantitative but not significant increase in the expression of Ucp1. Treatment with LDN-193189, an inhibitor of the BMP pathway, did not affect the differentiation of bovine myosatellite cells. Rather, LDN-193189 increased Ucp1 mRNA levels without modulating the levels of other brown/beige adipocyte-related genes. The current results indicate that the regulation of Ucp1 expression in bovine myogenic cells is distinct from that in murine brown/beige adipocytes, which has been more intensely characterized. SIGNIFICANCE OF THE STUDY: We previously reported unexpected expression of Ucp1 in bovine muscle tissues; Ucp1 expression has been known to be detected predominantly in brown/beige adipocytes. This study examined regulatory expression of bovine Ucp1 in myogenic cells. Consistent with the changes in expression levels of brown/beige adipocyte-selective genes, Ucp1 expression tended to be increased by inhibition of endogenous TGF-β activity. In contrast, inhibition of endogenous BMP significantly increased Ucp1 expression without affecting brown/beige adipocyte-selective gene expression. The current results indicate that regulatory expression of Ucp1 in bovine myogenic cells is distinct from that in murine brown/beige adipocytes that is more intensely characterized.