Effects of Tryptophan Supplementation in Diets with Different Protein Levels on the Production Performance of Broilers.

Tryptophan plays an important role in the pig industry but has the potential to improve performance in the poultry industry. The purpose of this study was to examine the effects of tryptophan supplementation in diets with different protein levels on the feed intake, average daily gain (ADG), and feed conversion ratio (F/G) of broilers. A total of 180 twenty-one-day-old broilers (half male and half female) were weighed and randomly allocated to twelve groups, with six male and six female groups. Each group consisted of 15 broilers. The broilers were fed low- (17.2%), medium- (19.2%), or high- (21.2%) protein diets with or without extra tryptophan (up to 0.25%) during the 28-day experiment. Food intake and body weight were measured weekly during the trial period. Male broilers fed a medium-protein diet containing more tryptophan showed a lower F/G. In the low-protein diet groups, additional tryptophan caused a significant reduction in the feed intake of female broilers during the first two weeks. Moreover, the serum GLP-1, cholesterol, and bile acid levels, as well as the expression of FXR mRNA in the ileum, were significantly increased. Additionally, the FXR mRNA in the hypothalamus and the GCG and GLP-1R mRNAs in the ileum tended to increase in these broilers. In summary, the tryptophan concentration in the diet can influence the feed intake and metabolism of broilers. Under a standard diet, an appropriate amount of tryptophan is beneficial to the F/G of male broilers, while under a low-protein diet, tryptophan supplementation may cause a short-term reduction in the feed intake of female broilers by increasing serum GLP-1 and bile acid signals.

[Corrigendum] Succinate promotes skeletal muscle protein synthesis via Erk1/2 signaling pathway.

Following the publication of the above article, the authors realized that, in Fig. 1D on p. 7363, the data panel selected for the '0.5 mM Succinate' group was duplicated in Fig. 1B (Control) in another article of theirs published in FASEB J ("α­Ketoglutarate prevents skeletal muscle protein degradation and muscle atrophy through PHD3/ADRB2 pathway": doi: 10.1096/fj.201700670R) due to the fact that they had inadvertently confused the layout of the two figures. The authors apologize for this error. Secondly, in terms of the quantification of the blots shown in Fig. 2A, ß­actin was not in fact used as a loading control; the phosphoproteins were normalized against the levels of the relative total protein, and the layout of Fig. 2A has been revised to reflect this (note that the the figure legend for Fig. 2 has also been revised: The last sentence no longer reads, "ß­actin was used as a loading control."). The revised versions of Figs. 1 and 2 are shown on the next page. Note that these errors did not affect the results or the main conclusions reported in the study, and no corrections were required either to the descriptions in the text or to the histograms shown in these figures. All the authors approve of the publication of this corrigendum, and the authors are grateful to the Editor of Molecular Medicine Reports for allowing them the opportunity to publish this. The authors regret their oversight in allowing these errors to be included in the paper, and apologize to the readership for any inconvenience caused. [Molecular Medicine Reports 16: 7361­7366, 2017; DOI: 10.3892/mmr.2017.7554].

Microbiota-derived 3-phenylpropionic acid promotes myotube hypertrophy by Foxo3/NAD+ signaling pathway.

BACKGROUND: Gut microbiota and their metabolites play a regulatory role in skeletal muscle growth and development, which be known as gut-muscle axis. 3-phenylpropionic acid (3-PPA), a metabolite produced by colonic microorganisms from phenylalanine in the gut, presents in large quantities in the blood circulation. But few study revealed its function in skeletal muscle development. RESULTS: Here, we demonstrated the beneficial effects of 3-PPA on muscle mass increase and myotubes hypertrophy both in vivo and vitro. Further, we discovered the 3-PPA effectively inhibited protein degradation and promoted protein acetylation in C2C12 and chick embryo primary skeletal muscle myotubes. Mechanistically, we supported that 3-PPA reduced NAD+ synthesis and subsequently suppressed tricarboxylic acid cycle and the mRNA expression of SIRT1/3, thus promoting the acetylation of total protein and Foxo3. Moreover, 3-PPA may inhibit Foxo3 activity by directly binding. CONCLUSIONS: This study firstly revealed the effect of 3-PPA on skeletal muscle growth and development, and newly discovered the interaction between 3-PPA and Foxo3/NAD+ which mechanically promote myotubes hypertrophy. These results expand new understanding for the regulation of gut microbiota metabolites on skeletal muscle growth and development.

Transcriptome analysis of adipose tissue and muscle of Laiwu and Duroc pigs.

Fat content is an important trait in pig production. Adipose tissue and muscle are important sites for fat deposition and affect production efficiency and quality. To regulate the fat content in these tissues, we need to understand the mechanisms behind fat deposition. Laiwu pigs, a Chinese indigenous breed, have significantly higher fat content in both adipose tissue and muscle than commercial breeds such as Duroc. In this study, we analyzed the transcriptomes in adipose tissue and muscle of 21-d-old Laiwu and Duroc piglets. Results showed that there were 828 and 671 differentially expressed genes (DEG) in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT), respectively. Functional enrichment analysis showed that these DEG were enriched in metabolic pathways, especially carbohydrate and lipid metabolism. Additionally, in the longissimus muscle (LM) and psoas muscle (PM), 312 and 335 DEG were identified, demonstrating enrichment in the cell cycle and metabolic pathways. The protein-protein interaction (PPI) networks of these DEG were analyzed and potential hub genes were identified, such as FBP1 and SCD in adipose tissues and RRM2 and GADL1 in muscles. Meanwhile, results showed that there were common DEG between adipose tissue and muscle, such as LDHB, THRSP, and DGAT2. These findings showed that there are significant differences in the transcriptomes of the adipose tissue and muscle between Laiwu and Duroc piglets (P < 0.05), especially in metabolic patterns. This insight serves to advance our comprehensive understanding of metabolic regulation in these tissues and provide targets for fat content regulation.

Conjugated linoleic acid (CLA) reduces intestinal fatty acid uptake and chylomicron formation in HFD-fed mice associated with the inhibition of DHHC7-mediated CD36 palmitoylation and the downstream ERK pathway.

The anti-obesity effect of conjugated linoleic acid (CLA) has been well elucidated, but whether CLA affects fat deposition by regulating intestinal dietary fat absorption remains largely unknown. Thus, this study aimed to investigate the effects of CLA on intestinal fatty acid uptake and chylomicron formation and explore the possible underlying mechanisms. We found that CLA supplementation reduced the intestinal fat absorption in HFD (high fat diet)-fed mice accompanied by the decreased serum TG level, increased fecal lipids and decreased intestinal expression of ApoB48 and MTTP. Correspondingly, c9, t11-CLA, but not t10, c12-CLA induced the reduction of fatty acid uptake and TG content in PA (palmitic acid)-treated MODE-K cells. In the mechanism of fatty acid uptake, c9, t11-CLA inhibited the binding of CD36 with palmitoyltransferase DHHC7, thus leading to the decreases of CD36 palmitoylation level and localization on the cell membrane of the PA-treated MODE-K cells. In the mechanism of chylomicron formation, c9, t11-CLA inhibited the formation of the CD36/FYN/LYN complex and the activation of the ERK pathway in the PA-treated MODE-K cells. In in vivo verification, CLA supplementation reduced the DHHC7-mediated total and cell membrane CD36 palmitoylation and suppressed the formation of the CD36/FYN/LYN complex and the activation of the ERK pathway in the jejunum of HFD-fed mice. Altogether, these data showed that CLA reduced intestinal fatty acid uptake and chylomicron formation in HFD-fed mice associated with the inhibition of DHHC7-mediated CD36 palmitoylation and the downstream ERK pathway.

Knockdown of the VEGFB/VEGFR1 signaling suppresses pubertal mammary gland development of mice via the inhibition of PI3K/Akt pathway.

Vascular endothelial growth factor B (VEGFB) has been well demonstrated to play a crucial role in regulating vascular function by binding to the VEGF receptors (VEGFRs). However, the specific role of VEGFB and VEGFRs in pubertal mammary gland development remains unclear. In this study, we observed that blocking the VEGF receptors with Axitinib suppressed the pubertal mammary gland development. Meanwhile, the proliferation of mammary epithelial cells (HC11) was repressed by blocking the VEGF receptors with Axitinib. Additionally, knockdown of VEGFR1 rather than VEGFR2 and NRP1 elicited the inhibition of HC11 proliferation, suggesting the essential role of VEGFR1 during this process. Furthermore, Axitinib or VEGFR1 knockdown led to the inhibition of the PI3K/Akt pathway. However, the inhibition of HC11 proliferation induced by Axitinib and or VEGFR1 knockdown was eliminated by the Akt activator SC79, indicating the involvement of the PI3K/Akt pathway. Finally, the knockdown of VEGFB and VEGFR1 suppressed the pubertal development of mice mammary gland with the inhibition of the PI3K/Akt pathway. In summary, the results showed that knockdown of the VEGFB/VEGFR1 signaling suppresses pubertal mammary gland development of mice via the inhibition of the PI3K/Akt pathway, which provides a new target for the regulation of pubertal mammary gland development.

Conjugated linoleic acid (CLA) reduces HFD-induced obesity by enhancing BAT thermogenesis and iWAT browning via the CD36-AMPK pathway.

The antiobesity effect of conjugated linoleic acid (CLA) has been reported. However, the underlying mechanisms have not been fully clarified. Thus, this study aimed to investigate the effects of CLA on thermogenesis of interscapular brown adipose tissue (iBAT) and browning of inguinal subcutaneous white adipose tissue (iWAT) and explore the possible signaling pathway. The in vivo results showed that CLA enhanced the O2 consumption and heat production in HFD (high-fat diet)-fed female mice by roughly 38%. Meanwhile, CLA increased the average iBAT temperature by 2°C at the room temperature and cold exposure, respectively. Correspondingly, CLA caused 1.6- and 2.4-fold increases in the expression of UCP1 (uncoupling protein 1) of BAT and iWAT, respectively, suggesting the activated iBAT thermogenesis and iWAT browning in HFD-fed female mice. Meanwhile, CLA could promote the formation of brown and beige adipocytes in differentiated stromal vascular cells (SVCs) isolated from iBAT and iWAT (the expressions of UCP1 were promoted by about twofold changes). In possible mechanisms, CLA stimulated the expression of CD36 and the activation of the AMPK pathway in mice iBAT and iWAT as well as the differentiated SVCs. However, inhibition of CD36 and AMPK (adenosine 5'-monophosphate-activated protein kinase) abolished the promotive effects of CLA on brown and beige adipocytes formation. Hence, we showed that CLA reduced HFD-induced obesity through enhancing iBAT thermogenesis and iWAT browning via the  CD36-AMPK pathway.

Integrated meta-omics reveals the regulatory landscape involved in lipid metabolism between pig breeds.

BACKGROUND: Domesticated pigs serve as an ideal animal model for biomedical research and also provide the majority of meat for human consumption in China. Porcine intramuscular fat content associates with human health and diseases and is essential in pork quality. The molecular mechanisms controlling lipid metabolism and intramuscular fat accretion across tissues in pigs, and how these changes in response to pig breeds, remain largely unknown. RESULTS: We surveyed the tissue-resident cell types of the porcine jejunum, colon, liver, and longissimus dorsi muscle between Lantang and Landrace breeds by single-cell RNA sequencing. Combining lipidomics and metagenomics approaches, we also characterized gene signatures and determined key discriminating markers of lipid digestibility, absorption, conversion, and deposition across tissues in two pig breeds. In Landrace, lean-meat swine mainly exhibited breed-specific advantages in lipid absorption and oxidation for energy supply in small and large intestinal epitheliums, nascent high-density lipoprotein synthesis for reverse cholesterol transport in enterocytes and hepatocytes, bile acid formation, and secretion for fat emulsification in hepatocytes, as well as intestinal-microbiota gene expression involved in lipid accumulation product. In Lantang, obese-meat swine showed a higher synthesis capacity of chylomicrons responsible for high serum triacylglycerol levels in small intestinal epitheliums, the predominant characteristics of lipid absorption in muscle tissue, and greater intramuscular adipcytogenesis potentials from muscular fibro-adipogenic progenitor subpopulation. CONCLUSIONS: The findings enhanced our understanding of the cellular biology of lipid metabolism and opened new avenues to improve animal production and human diseases. Video Abstract.

Plasma-derived exosomal protein SHP2 deficiency induces neutrophil hyperactivation in Behcet's uveitis.

To investigate the effect of plasma-derived exosomal proteins on neutrophil hyperactivation in Behcet's uveitis (BU), we treated neutrophils from healthy controls with plasma-derived exosomes from active BU patients, and determined the level of neutrophil activation by real-time quantitative PCR (RT-qPCR) and cytokine detection assay. The results revealed that exosomes from active BU patients could activate neutrophils as shown by increasing the expression levels of pro-inflammatory cytokines (IL-17 and IL-6), chemokines (IL-8 and MCP-1), and NETs (MPO and ELANE). Label-free quantitative proteomic analysis of plasma-derived exosomes from patients and healthy controls found a remarkably distinct protein profile and identified differentially expressed proteins (DEPs) between the two groups. The results of GO, KEGG, and GSEA enrichment analysis showed that DEPs were enriched in innate immune-mediated and neutrophil hyperactivation-related signaling pathways. The protein-protein interaction (PPI) analysis determined that SHP2 was a downregulated key hub protein in the exosomes of active BU patients. Knockdown of SHP2 in human neutrophil cell lines (NB4 cells) was shown to promote the secretion of pro-inflammatory cytokines, chemokines, and NETs. The converse effects were observed following SHP2 overexpression. In conclusion, we highlighted a pathogenic role of plasma-derived exosomal SHP2 deficiency in facilitating neutrophil activation and suggested that SHP2 might be an immunoprotective factor in BU pathologic process.

Microbiota derived D-malate inhibits skeletal muscle growth and angiogenesis during aging via acetylation of Cyclin A.

Metabolites derived from the intestinal microbiota play an important role in maintaining skeletal muscle growth, function, and metabolism. Here, we found that D-malate (DMA) is produced by mouse intestinal microorganisms and its levels increase during aging. Moreover, we observed that dietary supplementation of 2% DMA inhibits metabolism in mice, resulting in reduced muscle mass, strength, and the number of blood vessels, as well as the skeletal muscle fiber type I/IIb ratio. In vitro assays demonstrate that DMA decreases the proliferation of vascular endothelial cells and suppresses the formation of blood vessels. In vivo, we further demonstrated that boosting angiogenesis by muscular VEGFB injection rescues the inhibitory effects of D-malate on muscle mass and fiber area. By transcriptomics analysis, we identified that the mechanism underlying the effects of DMA depends on the elevated intracellular acetyl-CoA content and increased Cyclin A acetylation rather than redox balance. This study reveals a novel mechanism by which gut microbes impair muscle angiogenesis and may provide a therapeutic target for skeletal muscle dysfunction in cancer or aging.

Oxaloacetic acid induces muscle energy substrate depletion and fatigue by JNK-mediated mitochondrial uncoupling.

Fatigue is a common phenomenon closely related to physical discomfort and numerous diseases, which is severely threatening the life quality and health of people. However, the exact mechanisms underlying fatigue are not fully characterized. Herein, we demonstrate that oxaloacetic acid (OAA), a crucial tricarboxylic acid cycle intermediate, modulates the muscle fatigue. The results showed that serum OAA level was positively correlated with fatigue state of mice. OAA-treated induced muscle fatigue impaired the exercise performance of mice. Mechanistically, OAA increased the c-Jun N-terminal kinase (JNK) phosphorylation and uncoupling protein 2 (UCP2) levels in skeletal muscle, which led to decreased energy substrate and enhanced glycolysis. On the other hand, OAA boosted muscle mitochondrial oxidative phosphorylation uncoupled with energy production. In addition, either UCP2 knockout or JNK inhibition totally reversed the effects of OAA on skeletal muscle. Therein, JNK mediated UCP2 activation with OAA-treated. Our studies reveal a novel role of OAA in skeletal muscle metabolism, which would shed light on the mechanism of muscle fatigue and weakness.

4-Octyl Itaconate Inhibits Proinflammatory Cytokine Production in Behcet's Uveitis and Experimental Autoimmune Uveitis.

4-octyl itaconate (4-OI) is an anti-inflammatory metabolite that activates the nuclear-factor-E2-related factor 2 (NRF2) signaling. In the current work, we investigated whether 4-OI could affect the production of proinflammatory cytokines in Behcet's uveitis (BU) and experimental autoimmune uveitis (EAU). Peripheral blood mononuclear cells (PBMCs) of active BU patients and healthy individuals with in vitro 4-OI treatment were performed to assess the influence of 4-OI on the proinflammatory cytokine production. EAU was induced and used for investigating the influence of 4-OI on the proinflammatory cytokine production in vivo. The flow cytometry, qPCR, and ELISA were performed to detect proinflammatory cytokine expression. NRF2 signaling activation was evaluated by qPCR and western blotting (WB). Splenic lymphocyte transcriptome was performed by RNA sequencing. The NRF2 expression by BU patients-derived PBMCs was lower than that by healthy individuals. After treatment with 4-OI, the proportion of Th17 cells, along with the expression of proinflammatory cytokines (IL-17, TNF-α, MCP-1, and IL-6) by PBMCs, were downregulated, and anti-inflammatory cytokine (IL-10) expression was upregulated, although IFN-γ expression was unaffected. The EAU severity was ameliorated by 4-OI in association with a lower splenic Th1/Th17 cell proportion and increased nuclear NRF2 expression. Additionally, 4-OI downregulated a set of 248 genes, which were enriched in pathways of positive regulation of immune responses. The present study shows an inhibitory effect of 4-OI on the proinflammatory cytokine production in active BU patients and EAU mice, possibly mediated through activating NRF2 signaling. These findings suggest that 4-OI could act as a potential therapeutic drug for the treatment and prevention of BU in the future study.

A novel protein encoded by circKANSL1L regulates skeletal myogenesis via the Akt-FoxO3 signaling axis.

Skeletal muscle is one the largest organs of the body and is involved in animal production and human health. Circular RNAs (circRNAs) have been implicated in skeletal myogenesis through largely unknown mechanisms. Herein, we report the phenotypic and metabolomic analysis of porcine longissimus dorsi muscles in Lantang and Landrace piglets, revealing a high-content of slow-oxidative fibers responsible for high-quality meat product in Lantang piglets. Using single-cell transcriptomics, we identified four myogenesis-related cell types, and the Akt-FoxO3 signaling axis was the most significantly enriched pathway in each subpopulation in the different pig breeds, as well as in fast-twitch glycolytic fibers. Using the multi-dimensional bioinformatic tools of circRNAome-seq and Ribo-seq, we identified a novel circRNA, circKANSL1L, with a protein-coding ability in porcine muscles, whose expression level correlated with myoblast proliferation and differentiation in vitro, as well as the transformation between distinct mature myofibers in vivo. The protein product of circKANSL1L could interact with Akt to decrease the phosphorylation level of FoxO3, which subsequently promoted FoxO3 transcriptional activity to regulate skeletal myogenesis. Our results established the existence of a protein encoded by circKANSL1L and demonstrated its potential functions in myogenesis.

Browning of Mammary Fat Suppresses Pubertal Mammary Gland Development of Mice via Elevation of Serum Phosphatidylcholine and Inhibition of PI3K/Akt Pathway.

Mammary fat plays a profound role in the postnatal development of mammary glands. However, the specific types (white, brown, or beige) of adipocytes in mammary fat and their potential regulatory effects on modulating mammary gland development remain poorly understood. This study aimed to investigate the role of the browning of mammary fat on pubertal mammary gland development and explore the underlying mechanisms. Thus, the mammary gland development and the serum lipid profile were evaluated in mice treated with CL316243, a ß3-adrenoceptor agonist, to induce mammary fat browning. In addition, the proliferation of HC11 cells co-cultured with brown adipocytes or treated with the altered serum lipid metabolite was determined. Our results showed that the browning of mammary fat by injection of CL316243 suppressed the pubertal development of mice mammary glands, accompanied by the significant elevation of serum dioleoylphosphocholine (DOPC). In addition, the proliferation of HC11 was repressed when co-cultured with brown adipocytes or treated with DOPC. Furthermore, DOPC suppressed the activation of the PI3K/Akt pathway, while the DOPC-inhibited HC11 proliferation was reversed by SC79, an Akt activator, suggesting the involvement of the PI3K/Akt pathway in the DOPC-inhibited proliferation of HC11. Together, the browning of mammary fat suppressed the development of the pubertal mammary gland, which was associated with the elevated serum DOPC and the inhibition of the PI3K/Akt pathway.

Supplementation of microencapsulated probiotics modulates gut health and intestinal microbiota.

The beneficial effect of probiotics on host health is impaired due to the substantial loss of survivability during gastric transit caused by small intestinal enzymes and bile acids. Encapsulation helps to preserve the probiotics species from severe environmental factors. Lactobacillus paracasei, highly sensitive probiotic species to gastric acid, was encapsulated with polyacrylate resin. C57BL/6 male mice were equally divided into three groups; control group was fed with basal diet without any additives, the un-encapsulated group was fed with 0.1% of a mixture of encapsulating material and L. paracasei, and encapsulated group was fed with 0.1% encapsulated L. paracasei (microcapsule) for 4 weeks. The result showed elevated fecal moisture percentage in the encapsulated group, but not in the un-encapsulated group. Further study showed that the ratio of villus height to crypt depth in the small intestine was significantly higher compared to un-encapsulated and the control group. Microencapsulated probiotics also remarkably increased intestinal mucin and secretory immunoglobulin A (sIgA) concentration, intestinal MUC-2, and tight junction protein mRNA expression levels improving the intestinal barrier function of mice. In addition, microcapsules also reduced proinflammatory factor mRNA expression, while considerably increasing anti-inflammatory factor mRNA expression. Microbiota metabolites, fecal LPS (Lipopolysaccharide) were downregulated, and acetate and lactate were upraised compared to control. Furthermore, glutathione peroxidase (GSH-Px) and TAOC levels were increased and Malondialdehyde (MDA) was decreased improving antioxidant capacity. Microflora and bioinformatic predictive analysis of feces showed that encapsulated probiotics remarkably increased Lactobacillus proportions. Mice's intestinal health can thus be improved by using microencapsulated probiotics.

MiR-143 Targets SYK to Regulate NEFA Uptake and Contribute to Thermogenesis in Male Mice.

Excessive energy intake is the main cause of obesity, and stimulation of brown adipose tissue (BAT) and white adipose tissue (WAT) thermogenesis has emerged as an attractive tool for antiobesity. Although miR-143 has been reported to be associated with BAT thermogenesis, its role remains unclear. Here, we found that miR-143 had highest expression in adipose tissue, especially in BAT. During short-term cold exposure or CL316,243 was injected, miR-143 was markedly downregulated in BAT and subcutaneous WAT (scWAT). Moreover, knockout (KO) of miR-143 increases the body temperature of mice upon cold exposure, which may be due to the increased thermogenesis of BAT and scWAT. More importantly, supplementation of miR-143 in BAT of KO mice can inhibit the increase in body temperature in KO mice. Mechanistically, spleen tyrosine kinase was revealed for the first time as a new target of miR-143, and deletion of miR-143 facilitates fatty acid uptake in BAT. In addition, we found that brown adipocytes can promote fat mobilization of white adipocytes, and miR-143 may participate in this process. Meanwhile, we demonstrate that inactivation of adenylate cyclase 9 (AC9) in BAT inhibits thermogenesis through AC9-PKA-AMPK-CREB-UCP1 signaling pathway. Overall, our results reveal a novel function of miR-143 on thermogenesis, and a new functional link of the BAT and WAT.

Proline hydroxylase 2 (PHD2) promotes brown adipose thermogenesis by enhancing the hydroxylation of UCP1.

OBJECTIVE: Brown adipose tissue (BAT) plays a crucial role in regulating non-shivering thermogenesis under cold exposure. Proline hydroxylases (PHDs) were found to be involved in adipocyte differentiation and lipid deposition. However, the effects of PHDs on regulatory mechanisms of BAT thermogenesis are not fully understood. METHODS: We detected the expression of PHDs in different adipose tissues by using immunoblotting and real-time PCR. Further, immunoblotting, real-time PCR, and immunostaining were performed to determine the correlation between proline hydroxylase 2 (PHD2) and UCP1 expression. Inhibitor of PHDs and PHD2-sgRNA viruses were used to construct the PHD2-deficiency model in vivo and in vitro to investigate the impacts of PHD2 on BAT thermogenesis. Afterward, the interaction between UCP1 and PHD2 and the hydroxylation modification level of UCP1 were verified by Co-IP assays and immunoblotting. Finally, the effect of specific proline hydroxylation on the expression/activity of UCP1 was further confirmed by site-directed mutation of UCP1 and mass spectrometry analysis. RESULTS: PHD2, but not PHD1 and PHD3, was highly enriched in BAT, colocalized, and positively correlated with UCP1. Inhibition or knockdown of PHD2 significantly suppressed BAT thermogenesis under cold exposure and aggravated obesity of mice fed HFD. Mechanistically, mitochondrial PHD2 bound to UCP1 and regulated the hydroxylation level of UCP1, which was enhanced by thermogenic activation and attenuated by PHD2 knockdown. Furthermore, PHD2-dependent hydroxylation of UCP1 promoted the expression and stability of UCP1 protein. Mutation of the specific prolines (Pro-33, 133, and 232) in UCP1 significantly mitigated the PHD2-elevated UCP1 hydroxylation level and reversed the PHD2-increased UCP1 stability. CONCLUSIONS: This study suggested an important role for PHD2 in BAT thermogenesis regulation by enhancing the hydroxylation of UCP1.

Genetically prolonged beige fat in male mice confers long-lasting metabolic health.

A potential therapeutic target to curb obesity and diabetes is thermogenic beige adipocytes. However, beige adipocytes quickly transition into white adipocytes upon removing stimuli. Here, we define the critical role of cyclin dependent kinase inhibitor 2A (Cdkn2a) as a molecular pedal for the beige-to-white transition. Beige adipocytes lacking Cdkn2a exhibit prolonged lifespan, and male mice confer long-term metabolic protection from diet-induced obesity, along with enhanced energy expenditure and improved glucose tolerance. Mechanistically, Cdkn2a promotes the expression and activity of beclin 1 (BECN1) by directly binding to its mRNA and its negative regulator BCL2 like 1 (BCL2L1), activating autophagy and accelerating the beige-to-white transition. Reactivating autophagy by pharmacological or genetic methods abolishes beige adipocyte maintenance induced by Cdkn2a ablation. Furthermore, hyperactive BECN1 alone accelerates the beige-to-white transition in mice and human. Notably, both Cdkn2a and Becn1 exhibit striking positive correlations with adiposity. Hence, blocking Cdkn2a-mediated BECN1 activity holds therapeutic potential to sustain beige adipocytes in treating obesity and related metabolic diseases.

A one-dimensional cobalt-based coordination polymer as a cathode material of lithium-ion batteries.

For obtaining high-performance lithium-ion batteries, it is important to develop new cathode materials with high capacity. Herein, a one-dimensional coordination polymer [Co(4-DTBPT) (DMF)2(H2O)2] (4-DTBPT) (C10H4O8) (Co-DTBPT) (4-DTBPT = 2,7-di(4H-1,2,4-triazol-4yl)benzo[lmn][3,8] phenanthroline-1,3,6,8-(2H,7H)-tetraone; DMF = dimethylformamide) was synthesized and its electrochemical performance as the cathode material of lithium-ion batteries was first investigated. The Co-DTBPT electrode showed better cycling stability and a specific capacity of 55 mA h g-1 at 50 mA g-1 after 50 cycles, and the coulombic efficiency was close to 100%. The capacity contribution of the Co-DTBPT electrode may be ascribed to the redox reaction of the Co(II) ion and the 4-DTBPT ligand in the process of charge and discharge. Our work proves once again that using one-dimensional coordination polymers as cathode materials for lithium-ion batteries is a feasible way.