ABSTRACT
Heightened unfolded protein responses (UPRs) are associated with the risk for asthma, including severe asthma. Treatment-refractory severe asthma manifests a neutrophilic phenotype with T helper (Th)17 responses. However, how UPRs participate in the deregulation of Th17 cells leading to neutrophilic asthma remains elusive. This study found that the UPR sensor IRE1 is induced in the murine lung with fungal asthma and is highly expressed in Th17 cells relative to naive CD4+ T cells. Cytokine (e.g., IL-23) signals induce the IRE1-XBP1s axis in a JAK2-dependent manner. This noncanonical activation of the IRE1-XBP1s pathway promotes UPRs and cytokine secretion by both human and mouse Th17 cells. Ern1 (encoding IRE1) deficiency decreases the expression of endoplasmic reticulum stress factors and impairs the differentiation and cytokine secretion of Th17 cells. Genetic ablation of Ern1 leads to alleviated Th17 responses and airway neutrophilia in a fungal airway inflammation model. Consistently, IL-23 activates the JAK2-IRE1-XBP1s pathway in vivo and enhances Th17 responses and neutrophilic infiltration into the airway. Taken together, our data indicate that IRE1, noncanonically activated by cytokine signals, promotes neutrophilic airway inflammation through the UPR-mediated secretory function of Th17 cells. The findings provide a novel insight into the fundamental understanding of IRE1 in Th17-biased TH2-low asthma.
Subject(s)
Asthma , Endoribonucleases , Neutrophils , Protein Serine-Threonine Kinases , Th17 Cells , Animals , Th17 Cells/immunology , Th17 Cells/metabolism , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Neutrophils/immunology , Neutrophils/metabolism , Humans , Endoribonucleases/metabolism , Endoribonucleases/genetics , Asthma/immunology , Asthma/pathology , Asthma/metabolism , Unfolded Protein Response , Mice , Mice, Inbred C57BL , Interleukin-23/metabolism , Interleukin-23/immunology , Endoplasmic Reticulum Stress/immunology , X-Box Binding Protein 1/metabolism , X-Box Binding Protein 1/genetics , Signal Transduction , Mice, Knockout , Lung/immunology , Lung/pathology , Lung/metabolismABSTRACT
Background: Syndrome of inappropriate antidiuretic(SIAD) occurs secondary to various diseases, which is characterised by hypotonic hyponatremia and impaired urinary diluting capacity. Research on SIAD in both domestic and international contexts has a long history. This study objectively and comprehensively analyses the research trends, hotspots and development of SIAD research of the past 20 years using the method of bibliometric analysis. Methods: The 2003-2022 data in the Web of Science Core Collection database were searched. The Bibliometrix software package, VOSviewer and CiteSpace were used to mine, extract and visualise the retrieved literature, and the generated maps were used in analysing the main topics and trends in the field of SIAD research. Results: A total of 1215 articles published in 623 journals were included in the analysis, with a total of 18,886 citations. Results showed that the research output on SIAD has continuously increased in the past 20 years, and the United States had the highest number of publications and citations. Keywords with the highest burst strength in recent years were the most mentioned keywords, in addition to the search terms 'hyponatremia', 'covid-19', and 'mortality'. Thus, the relationship among SIAD, covid-19 and mortality may become research frontiers and trends. Fifteen milestone articles were identified through co-citation analysis, which mainly focused on the pathophysiology and treatment of SIAD. Conclusion: Based on bibliometric analysis and knowledge mapping, this study summarises development trends in the field of SIAD research, providing references for current and future research into SIAD.
Subject(s)
COVID-19 , Hyponatremia , Humans , Bibliometrics , COVID-19/epidemiology , Databases, Factual , KnowledgeABSTRACT
The coexistence of brown adipocytes with low and high thermogenic activity is a fundamental feature of brown adipose tissue heterogeneity and plasticity. However, the mechanisms that govern thermogenic adipocyte heterogeneity and its significance in obesity and metabolic disease remain poorly understood. Here we show that in male mice, a population of transcription factor jun-B (JunB)-enriched (JunB+) adipocytes within the brown adipose tissue exhibits lower thermogenic capacity compared to high-thermogenic adipocytes. The JunB+ adipocyte population expands in obesity. Depletion of JunB in adipocytes increases the fraction of adipocytes exhibiting high thermogenic capacity, leading to enhanced basal and cold-induced energy expenditure and protection against diet-induced obesity and insulin resistance. Mechanistically, JunB antagonizes the stimulatory effects of PPARγ coactivator-1α on high-thermogenic adipocyte formation by directly binding to the promoter of oestrogen-related receptor alpha, a PPARγ coactivator-1α downstream effector. Taken together, our study uncovers that JunB shapes thermogenic adipocyte heterogeneity, serving a critical role in maintaining systemic metabolic health.
Subject(s)
Insulin Resistance , Mice , Male , Animals , PPAR gamma/metabolism , Adipocytes, Brown/metabolism , Obesity/etiology , Obesity/metabolism , Diet, High-Fat , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
A Chinese family was identified to have two patients with rickets, an adult female and a male child (proband), both exhibiting signs related to X-linked hypophosphatemic rickets (XLH). Gene sequencing analysis revealed a deletion of adenine at position 1985 (c.1985delA) in the PHEX-encoding gene. To investigate the relationship between this mutation and the pathogenicity of XLH, as well as analyze the effects of different dosages of PHEX gene mutations on clinical phenotypes, we developed a rat model carrying the PHEX deletion mutation. The CRISPR/Cas9 gene editing technology was employed to construct the rat model with the PHEX gene mutation (c.1985delA). Through reproductive procedures, five genotypes of rats were obtained: female wild type (X/X), female heterozygous (-/X), female homozygous wild type (-/-), male wild type (X/Y), and male hemizygous (-/Y). The rats with different genotypes underwent analysis of growth, serum biochemical parameters, and bone microstructure. The results demonstrated the successful generation of a stable rat model inheriting the PHEX gene mutation. Compared to the wild-type rats, the mutant rats displayed delayed growth, shorter femurs, and significantly reduced bone mass. Among the female rats, the homozygous individuals exhibited the smallest body size, decreased bone mass, shortest femur length, and severe deformities. Moreover, the mutant rats showed significantly lower blood phosphorus concentration, elevated levels of FGF23 and alkaline phosphatase, and increased expression of phosphorus regulators. In conclusion, the XLH rat model with the PHEX gene mutation dosage demonstrated its impact on growth and development, serum biochemical parameters, and femoral morphology.
Subject(s)
Familial Hypophosphatemic Rickets , Animals , Female , Male , Rats , Familial Hypophosphatemic Rickets/genetics , Familial Hypophosphatemic Rickets/diagnosis , Genotype , Mutation , Pedigree , PHEX Phosphate Regulating Neutral Endopeptidase/genetics , PhosphorusABSTRACT
Dysfunctional mitochondria are removed via multiple pathways, such as mitophagy, a selective autophagy process. Here, we identify an intracellular hybrid mitochondria-lysosome organelle (termed the mitochondria-lysosome-related organelle [MLRO]), which regulates mitochondrial homeostasis independent of canonical mitophagy during hepatocyte dedifferentiation. The MLRO is an electron-dense organelle that has either a single or double membrane with both mitochondria and lysosome markers. Mechanistically, the MLRO is likely formed from the fusion of mitochondria-derived vesicles (MDVs) with lysosomes through a PARKIN-, ATG5-, and DRP1-independent process, which is negatively regulated by transcription factor EB (TFEB) and associated with mitochondrial protein degradation and hepatocyte dedifferentiation. The MLRO, which is galectin-3 positive, is reminiscent of damaged lysosome and could be cleared by overexpression of TFEB, resulting in attenuation of hepatocyte dedifferentiation. Together, results from this study suggest that the MLRO may act as an alternative mechanism for mitochondrial quality control independent of canonical autophagy/mitophagy involved in cell dedifferentiation.
Subject(s)
Mitochondria , Organelles , Mitochondria/metabolism , Organelles/metabolism , Lysosomes/metabolism , Autophagy/physiology , Mitophagy/physiologyABSTRACT
Treatment-refractory severe asthma manifests a neutrophilic phenotype associated with TH17 responses. Heightened unfolded protein responses (UPRs) are associated with the risk of asthma, including severe asthma. However, how UPRs participate in the deregulation of TH17 cells leading to this type of asthma remains elusive. In this study, we investigated the role of the UPR sensor IRE1 in TH17 cell function and neutrophilic airway inflammation. We found that IRE1 is induced in fungal asthma and is highly expressed in TH17 cells relative to naïve CD4+ T cells. Cytokine (e.g. IL-23) signals induce the IRE1-XBP1s axis in a JAK2-dependent manner. This noncanonical activation of the IRE1-XBP1s pathway promotes UPRs and cytokine secretion by TH17 cells. Ern1 (encoding IRE1)-deficiency decreases the expression of ER stress factors and impairs the differentiation and cytokine secretion of TH17 cells. Genetic ablation of Ern1 leads to alleviated TH17 responses and airway neutrophilia in a Candida albicans asthma model. Consistently, IL-23 activates the JAK2-IRE1-XBP1s pathway in vivo and enhances TH17 responses and neutrophilic infiltration into the airway. Taken together, our data indicate that IRE1, noncanonically activated by cytokine signals, promotes neutrophilic airway inflammation through the UPRmediated secretory function of TH17 cells. The findings provide a novel insight into the fundamental understanding of IRE1 in TH17-biased TH2-low asthma.
ABSTRACT
The unfolded protein response (UPR) is associated with the risk of asthma, including treatment-refractory severe asthma. Recent studies demonstrated a pathogenic role of activating transcription factor 6a (ATF6a or ATF6), an essential UPR sensor, in airway structural cells. However, its role in T helper (TH) cells has not been well examined. In this study, we found that ATF6 was selectively induced by signal transducer and activator of transcription6 (STAT6) and STAT3 in TH2 and TH17 cells, respectively. ATF6 upregulated UPR genes and promoted the differentiation and cytokine secretion of TH2 and TH17 cells. T cell-specific Atf6-deficiency impaired TH2 and TH17 responses in vitro and in vivo and attenuated mixed granulocytic experimental asthma. ATF6 inhibitor Ceapin A7 suppressed the expression of ATF6 downstream genes and TH cell cytokines by both murine and human memory clusters of differentiation 4 (CD4)+ T cells. At the chronic stage of asthma, administration of Ceapin A7 lessened TH2 and TH17 responses, leading to alleviation of both airway neutrophilia and eosinophilia. Thus, our results demonstrate a critical role of ATF6 in TH2 and TH17 cell-driven mixed granulocytic airway disease, suggesting a novel option to combat steroid-resistant mixed and even T2-low endotypes of asthma by targeting ATF6.
Subject(s)
Asthma , Th2 Cells , Mice , Humans , Animals , Th2 Cells/metabolism , Asthma/metabolism , Granulocytes/metabolism , Inflammation/metabolism , Th17 Cells/metabolism , Disease Models, Animal , Activating Transcription Factor 6/genetics , Activating Transcription Factor 6/metabolismABSTRACT
Activin A plays an essential role in ischemic stroke as a well-known neuroprotective factor. We previously reported that Activin A could promote white matter remyelination. However, the exact molecular mechanism of Activin A in neuronal protection post-stroke is still unclear. In this study, the middle cerebral artery occlusion/reperfusion (MCAO/R)-induced ischemic stroke mouse model and oxygen-glucose deprivation/reoxygenation (OGD/R)-treated primary neurons were used to explore the molecular mechanism of Activin A-mediated neuroprotection against ischemic injuries. We found that Activin A significantly inhibits cGAS-STING-mediated excessive autophagy through the PI3K-PKB pathway, but not mTOR-dependent autophagy. Consequently, Activin A protected neurons against OGD/R-induced ischemic injury and improved cell survival in a dose-dependent manner. In addition, Activin A improved neurological functions and reduced infarct size of mice with MCAO/R-induced ischemic stroke by inhibiting autophagy. Furthermore, Activin A depended on ACVR1C receptor to exert neuroprotective effects in 1 h MCAO/R treated mice. Our findings showed that Activin A alleviated neuronal ischemic injury through inhibiting cGAS-STING-mediated excessive autophagy in mice with ischemic stroke, which may suggest a potential therapeutic target for ischemic stroke.
Subject(s)
Brain Ischemia , Ischemic Stroke , Neuroprotective Agents , Reperfusion Injury , Mice , Animals , Brain Ischemia/metabolism , Ischemic Stroke/metabolism , Autophagy/physiology , Neurons/metabolism , Reperfusion Injury/prevention & control , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Neuroprotective Agents/metabolism , Infarction, Middle Cerebral Artery/metabolismABSTRACT
PURPOSE: To explore the safety and role of tegafur/gimeracil/oteracil (S1) maintenance therapy (MT) in metastatic nasopharyngeal carcinoma (NPC) patients after response to first-line chemotherapy and to assess outcome-associated biomarkers. METHODS: This was a multicentre, open-label, randomized controlled study involving metastatic NPC patients recruited (from May 2015 to May 2019) at five hospitals in China. The participants were randomized to S1-MT (receiving S1 MT until disease progression or intolerance) or non-MT (followed up until disease progression) groups. The primary endpoint was the progression-free survival (PFS). The secondary endpoints were the overall survival (OS), the correlation between EBV-DNA, serum amyloid A (SAA) status, and outcomes after the first-line chemotherapy, and safety. RESULTS: The median follow-up was 24.3 months; 88 and 95 participants were evaluable in the S1-MT and non-MT groups, respectively. Compared with non-MT, S1-MT prolonged PFS (16.9 vs. 9.3 months, P < 0.001) and OS (33.6 vs. 20.6 months, P < 0.001). Regardless of their EBV-DNA status after first-line chemotherapy, participants were able to benefit from S1 MT, but EBV-DNA-positive participants benefited more significantly (PFS: HR = 0.600, 95% CI = 0.373-0.965, P = 0.035; OS: HR = 0.393, 95% CI = 0.227-0.681, P = 0.001). MT only improved PFS and OS in patients with an SAA decline after first-line chemotherapy (PFS: HR = 0.570, 95% CI = 0.350-0.919, P = 0.021; OS: HR = 0.404, 95% CI = 0.230-0.709, P = 0.002). The median S1 treatment was 23 cycles. Grade 1-2 skin pigmentation, oral mucositis, and hand and foot syndrome were the main adverse reactions. CONCLUSION: For metastatic NPC patients with first-line chemotherapy response, S1 MT can improve PFS and OS, with good tolerability. EBV-DNA and SAA can better help us identify patients who can benefit from MT after standard treatment. TRIAL REGISTRATION: The study protocol was registered at the Chinese Clinical Trial Registry (ChiCTR-IOR-16007939).
Subject(s)
Nasopharyngeal Neoplasms , Humans , Nasopharyngeal Carcinoma/drug therapy , Progression-Free Survival , Disease Progression , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/pathology , China , Antineoplastic Combined Chemotherapy Protocols/therapeutic useABSTRACT
Doublesex and Mab-3 related Transcription Factor 3 (DMRT3) is associated with the prognosis of some tumors. It is possible to explore the role of DMRT3 in the cancer process using bioinformatic approaches and experimental validation. We comprehensively explored the clinical and immunological characteristics of DMRT3. The DMRT3 expression is abnormal in human cancers and correlates with clinical staging. A high DMRT3 expression is significantly associated with poor overall survival (OS) in KIRC, KIRP, LUAD, and UCEC. Amplification was the greatest frequency of the DMRT3 alterations in pan-cancer. The OS was significantly lower in the DMRT3 altered group than in the DMRT3 unaltered group (P = 0.0276). The DMRT3 expression was significantly associated with MSI in three cancer types and TMB in six cancer types. The DMRT3 expression was significantly correlated with the level of the immune cell infiltration and the immune checkpoint genes. The DMRT3 was involved in some pathways in pan-cancer. DMRT3 may play a role in chemotherapy and may be associated with chemoresistance. A ceRNA network of KCNQ1OT1/miR-335-5p/DMRT3 was constructed in LUAD. DMRT3 was significantly upregulated in the LUAD cell lines. DMRT3 was aberrantly expressed in pan-cancer and may promote tumorigenesis and progression via different mechanisms. DMRT3 can be used as a therapeutic target to treat cancer in humans.
ABSTRACT
BACKGROUND: To date, no study has evaluated trends in the burden of alcohol-induced cirrhosis and other chronic liver diseases based on the Global Burden of Diseases, Injuries, and Risk Factors (GBD) 2019 study. Herein, we report on the global burden of alcohol-induced cirrhosis and other chronic liver diseases in terms of age, sex, and sociodemographic index (SDI) from 1990 to 2019, based on analysis of GBD 2019 data. METHODS: The estimated annual percentage change (EAPC) was calculated to determine the trends in the age-standardized incidence and mortality rates and disability-adjusted life years (DALYs) for alcohol-induced cirrhosis and other chronic liver diseases. RESULTS: From 1990 to 2019, the global age-standardized incidence rate showed an upward trend (EAPC = 0.10), whereas the global age-standardized mortality rate and DALYs showed a downward trend (EAPC = - 0.88 and - 0.89, respectively). Low-(187.08 in 2019) and low-middle (178.11 in 2019)SDI regions had much higher age-standardized DALYs. Eastern Europe saw the largest increases in the age-standardized mortality rate and DALYs. Lithuania had the largest increase in mortalities caused by alcohol-induced cirrhosis and other chronic liver diseases(EAPC = 4.61). The age-standardized mortality rates and DALYs were higher in men than in women. CONCLUSION: From 1990 to 2019, the age-standardized incidence rate of alcohol-induced cirrhosis and other chronic liver diseases increased globally; however, both the age-standardized mortality rate and DALYs caused by alcohol-induced cirrhosis and other chronic liver diseases showed decreasing trends. Future studies should devise preventive strategies for low and low-middle SDI regions, Eastern Europe, Lithuania, and other high-risk regions.
Subject(s)
Global Burden of Disease , Liver Cirrhosis , Male , Humans , Female , Liver Cirrhosis/epidemiology , Liver Cirrhosis, Alcoholic/epidemiology , Alcohol Drinking/adverse effects , Alcohol Drinking/epidemiology , IncidenceABSTRACT
A unique feature of the liver is its high regenerative capacity, which is essential to maintain liver homeostasis. However, key regulators of liver regeneration (LR) remain ill-defined. Here, we identify hepatic miR-182-5p as a key regulator of LR. Suppressing miR-182-5p, whose expression is significantly induced in the liver of mice post two-thirds partial hepatectomy (PH), abrogates PH-induced LR in mice. In contrast, liver-specific overexpression of miR-182-5p promotes LR in mice with PH. Overexpression of miR-182-5p failed to promote proliferation in hepatocytes, but stimulates proliferation when hepatocytes are cocultured with stellate cells. Mechanistically, miR-182-5p stimulates Cyp7a1-mediated cholic acid production in hepatocytes, which promotes hedgehog (Hh) ligand production in stellate cells, leading to the activation of Hh signaling in hepatocytes and consequent cell proliferation. Collectively, our study identified miR-182-5p as a critical regulator of LR and uncovers a Cyp7a1/cholic acid-dependent mechanism by which hepatocytes crosstalk to stellate cells to facilitate LR.
Subject(s)
Liver Regeneration , MicroRNAs , Animals , Cholic Acid/metabolism , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Hepatocytes/metabolism , Liver Regeneration/genetics , Mice , MicroRNAs/genetics , MicroRNAs/metabolismABSTRACT
Since 2013, a pilot market of carbon emission trading scheme (ETS) has operated in China, with results showing a reduction in the carbon intensity of the economy. How does ETS affect enterprises' environmental protection behaviors? We conducted a quasinatural experiment by using A-share-listed companies from 2010 to 2019 as research samples and matching them using the propensity score matching method. The difference in differences model was then used to empirically assess the effect and influencing mechanism of the ETS on corporate environmental investment. Finally, the robustness and heterogeneity of the empirical results were checked. ETS seems to have significantly increased the levels of capitalized and expense-based environmental protection investment. Among them, low-carbon technological innovation plays an intermediary role in the impact of ETS on capitalized environmental protection investment. State-owned enterprises preferred capitalized environmental protection investment, whereas private enterprises preferred expense-based environmental protection investment. Moreover, having a political connection could compromise the role of ETS in promoting environmental protection investment. Our study provides some suggestions, such as accelerating the rollout of low-carbon technologies, increasing financial support for private enterprises, establishing an official reputation mechanism, and strengthening the transparency of carbon emission information disclosure.
Subject(s)
Carbon , Conservation of Natural Resources , Carbon/analysis , Investments , Organizations , ChinaABSTRACT
Cyclooxygenase-2 (COX-2) plays a critical role in regulating innate immunity and metabolism by producing prostaglandins (PGs) and other lipid mediators. However, the implication of adipose COX-2 in obesity remains largely unknown. Using adipocyte-specific COX-2 knockout (KO) mice, we showed that depleting COX-2 in adipocytes promoted white adipose tissue development accompanied with increased size and number of adipocytes and predisposed diet-induced adiposity, obesity, and insulin resistance. The increased size and number of adipocytes by COX-2 KO were reversed by the treatment of prostaglandin E2 (PGE2) but not PGI2 and PGD2 during adipocyte differentiation. PGE2 suppresses PPARγ expression through the PKA pathway at the early phase of adipogenesis, and treatment of PGE2 or PKA activator isoproterenol diminished the increased lipid droplets in size and number in COX-2 KO primary adipocytes. Administration of PGE2 attenuated increased fat mass and fat percentage in COX-2 deficient mice. Taken together, our study demonstrated the suppressing effect of adipocyte COX-2 on adipogenesis and reveals that COX-2 restrains adipose tissue expansion via the PGE2-mediated paracrine mechanism and prevents the development of obesity and related metabolic disorders.
Subject(s)
Adipogenesis , Cyclooxygenase 2 , Dinoprostone , Obesity , Animals , Cyclooxygenase 2/deficiency , Cyclooxygenase 2/genetics , Diet, High-Fat/adverse effects , Dinoprostone/metabolism , Mice , Mice, Knockout , Obesity/geneticsABSTRACT
Background: The aim of the present study was to summarize the clinical and pathological characteristics of 11 non-small cell lung cancer (NSCLC) patients with mesenchymal-epithelial transition factor exon 14 skipping (METex14). Methods: From 2018 to 2021, medical records of 763 NSCLC patients were reviewed and 11 patients carrying METex14 were identified from the Affiliated Hospital of Guangdong Medical University. Their clinical data were subsequently examined for pathological and related clinical information including symptom and diagnosis, imaging and follow-up. Results: The METex14 cohort includes 9 males and 2 females and the age range was 69-85 years, with a median age of 77 years. Of the patients one is diagnosed with stage IVB lung adenosquamous carcinoma, 7 with lung adenocarcinoma (1 with stage IIIA and 6 with stage IV), and 3 with stage IV lung sarcomatoid carcinoma. 3 reached stable disease until the end of follow-up and 4 died within a year due to multiple metastases. In 4 cases, the patients received selective MET inhibitor treatment all lived longer than 7 months. There were 4 heterozygous point mutations and 1 deletion of the MET gene in this cohort, as follows: c.G3028T (p.D1010Y); c.G3028A (p.D1010N); c.G3005C (p.V1002A); c.3022C>G and MET c.3021_3028+20del (E14). Conclusions: According to the data that we collected, the incidence of NSCLC carrying METex14 is low and male outnumber female in our sample pool. Selective target therapy had better prognosis than multitargeted tyrosine kinase inhibitor (TKI) such as crizotinib or standard therapy.
ABSTRACT
The intermittent fasting (IF) diet has profound benefits for diabetes prevention. However, the precise mechanisms underlying IF's beneficial effects remain poorly defined. Here, we show that the expression levels of cyclooxygenase-2 (COX-2), an enzyme that produces prostaglandins, are suppressed in white adipose tissue (WAT) of obese humans. In addition, the expression of COX-2 in WAT is markedly upregulated by IF in obese mice. Adipocyte-specific depletion of COX-2 led to reduced fractions of CD4+Foxp3+ Tregs and a substantial decrease in the frequency of CD206+ macrophages, an increase in the abundance of γδT cells in WAT under normal chow diet conditions, and attenuation of IF-induced antiinflammatory and insulin-sensitizing effects, despite a similar antiobesity effect in obese mice. Mechanistically, adipocyte-derived prostaglandin E2 (PGE2) promoted Treg proliferation through the CaMKII pathway in vitro and rescued Treg populations in adipose tissue in COX-2-deficient mice. Ultimately, inactivation of Tregs by neutralizing anti-CD25 diminished IF-elicited antiinflammatory and insulin-sensitizing effects, and PGE2 restored the beneficial effects of IF in COX-2-KO mice. Collectively, our study reveals that adipocyte COX-2 is a key regulator of Treg proliferation and that adipocyte-derived PGE2 is essential for IF-elicited type 2 immune response and metabolic benefits.
Subject(s)
Dinoprostone , Insulin Resistance , Adipocytes/metabolism , Animals , Cell Proliferation , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Dinoprostone/metabolism , Fasting , Insulin/metabolism , Insulin Resistance/physiology , Mice , Mice, Obese , T-Lymphocytes, RegulatoryABSTRACT
Adiponectin is an adipokine predominantly produced by fat cells, circulates and exerts insulin-sensitizing, cardioprotective and anti-inflammatory effects. Dysregulation of adiponectin and/or adiponectin signaling is implicated in a number of metabolic diseases such as obesity, insulin resistance, diabetes, and cardiovascular diseases. However, while the insulin-sensitizing and cardioprotective effects of adiponectin have been widely appreciated in the field, the obesogenic and anti-inflammatory effects of adiponectin are still of much debate. Understanding the physiological function of adiponectin is critical for adiponectin-based therapeutics for the treatment of metabolic diseases.
ABSTRACT
Glucocorticoids (GCs), a class of corticosteroids produced by the adrenal cortex in response to stress, exert obesity-promoting effects. Although adaptive thermogenesis has been considered an effective approach to counteract obesity, whether GCs play a role in regulating cold stress-induced thermogenesis remains incompletely understood. Here, we show that the circulating levels of stress hormone corticosterone (GC in rodents) were significantly elevated, whereas the levels of adiponectin, an adipokine that was linked to cold-induced adaptive thermogenesis, were decreased 48 h post cold exposure. The administration of a glucocorticoid hydrocortisone downregulated adiponectin protein and mRNA levels in both WAT and white adipocytes, and upregulated thermogenic gene expression in inguinal fat. In contrast, mifepristone, a glucocorticoid receptor antagonist, enhanced adiponectin expression and suppressed energy expenditure in vivo. Mechanistically, hydrocortisone suppressed adiponectin expression by antagonizing PPARγ in differentiated 3T3-L1 adipocytes. Ultimately, adiponectin deficiency restored mifepristone-decreased oxygen consumption and suppressed the expression of thermogenic genes in inguinal fat. Taken together, our study reveals that the GCs/adiponectin axis is a key regulator of beige fat thermogenesis in response to acute cold stress.
Subject(s)
Adipose Tissue, Beige , Adiponectin/deficiency , Animals , Glucocorticoids , Metabolism, Inborn Errors , MiceABSTRACT
A dynamically regulated microenvironment, which is mediated by crosstalk between adipocytes and neighboring cells, is critical for adipose tissue homeostasis and function. However, information on key molecules and/or signaling pathways regulating the crosstalk remains limited. In this study, we identify adipocyte miRNA-182-5p (miR-182-5p) as a crucial antiobesity molecule that stimulated beige fat thermogenesis by promoting the crosstalk between adipocytes and macrophages. miR-182-5p was highly enriched in thermogenic adipocytes, and its expression was markedly stimulated by cold exposure in mice. In contrast, miR-182-5p expression was significantly reduced in adipose tissues of obese humans and mice. Knockout of miR-185-5p decreased cold-induced beige fat thermogenesis whereas overexpression of miR-185-5p increased beiging and thermogenesis in mice. Mechanistically, miR-182-5p promoted FGF21 expression and secretion in adipocytes by suppressing nuclear receptor subfamily 1 group D member 1 (Nr1d1) at 5'-UTR, which in turn stimulates acetylcholine synthesis and release in macrophages. Increased acetylcholine expression activated the nicotine acetylcholine receptor in adipocytes, which stimulated PKA signaling and consequent thermogenic gene expression. Our study reveals a key role of the miR-182-5p/FGF21/acetylcholine/acetylcholine receptor axis that mediates the crosstalk between adipocytes and macrophages to promote beige fat thermogenesis. Activation of the miR-182-5p-induced signaling pathway in adipose tissue may be an effective approach to ameliorate obesity and associated metabolic diseases.
Subject(s)
Acetylcholine/genetics , Adipocytes/metabolism , Fibroblast Growth Factors/genetics , Macrophages/metabolism , MicroRNAs/genetics , Obesity/genetics , Thermogenesis/genetics , Acetylcholine/biosynthesis , Adipocytes/pathology , Adipose Tissue/cytology , Adipose Tissue/metabolism , Animals , Disease Models, Animal , Fibroblast Growth Factors/biosynthesis , Macrophages/pathology , Mice , Mice, Knockout , MicroRNAs/biosynthesis , Obesity/metabolism , Obesity/pathology , Signal TransductionABSTRACT
Bladder cancer is a common malignancy in the urinary system. Stromal and immune cells in tumor microenvironments, including those in the bladder cancer microenvironment, can serve as prognostic markers. However, the complex processes of bladder cancer necessitate large-scale evaluation to better understand the underlying mechanisms and identify biomarkers for diagnosis and treatment. We used the Estimation of STromal and Immune cells in MAlignant Tumors using Expression data algorithm to assess the association between stromal and immune cell-related genes and overall survival of patients with bladder cancer. We also identified and evaluated differentially expressed genes between cancer and non-cancer tissues from The Cancer Genome Atlas. Patients were categorized into different prognosis groups according to their stromal/immune scores based on differential gene expression. In addition, the prognostic value of the differentially expressed genes was assessed in a separate validation cohort using the Gene Expression Omnibus microarray dataset GSE13507, which identified nine genes (TNC, CALD1, PALLD, TAGLN, TGFB1I1, HSPB6, RASL12, CPXM2, and CYR61) associated with overall survival. Multivariate regression analysis showed that three genes (TNC, CALD1, and PALLD) were possible independent prognostic markers for patients with bladder cancer. Multiple gene set enrichment analysis of individual genes showed strong correlations with stromal and immune interactions, indicating that these nine genes may be related to carcinogenesis, invasion, and metastasis of bladder cancer. These findings provide useful insight into the molecular mechanisms of bladder cancer development, and suggest candidate biomarkers for prognosis and treatment.