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Dai J, Dong X, Chen Y, Xue W, Wang Q, Shang F, Zhao Y, Li S, Gao Y, Wang Y. SPOP regulates the expression profiles and alternative splicing events in human hepatocytes. Open Life Sci 2023; 18:20220755. [PMID: 37941785 PMCID: PMC10628592 DOI: 10.1515/biol-2022-0755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 09/08/2023] [Accepted: 09/19/2023] [Indexed: 11/10/2023] Open
Abstract
Speckle type BTB/POZ protein (SPOP) may have cancer promoting or inhibiting effects. At present, the role of SPOP in hepatocellular carcinoma (HCC) has rarely been studied. In this study, to investigate the effects of SPOP in HCC and elucidate the underlying molecular mechanisms of its relationship with genes, differentially expressed genes (DEGs) were classified through RNA sequencing. The gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes functional pathway analysis were used to further predict the function of DEGs after the overexpression of SPOP. The biological function of SPOP-regulated alternative splicing events in cells is comprehensively assessed. The Cancer Genome Atlas database and Gene Expression Omnibus dataset were performed to evaluate the correlation between SPOP and HCC progression. Due to SPOP overexpression, 56 DEGs in the HCC related pathway were further identified. The results showed that SPOP overexpression facilitated the cell proliferation and changed the gene expression profiles of human normal hepatocytes. SPOP-regulated alternative splicing events were involved in pathways associated with cellular processes, metabolism, environmental information procession, organismal systems, and so on. In conclusion, SPOP may potentially exhibit tumor-promoting effects, necessitating further investigations to unveil its molecular mechanisms comprehensively.
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Affiliation(s)
- Jing Dai
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
| | - Xiang Dong
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
- Research Center of Clinical Laboratory Science, School of Laboratory Medicine, Bengbu Medical College, Bengbu, China
| | - Yuxin Chen
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
| | - Wanying Xue
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
| | - Qingqing Wang
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
| | - Feifei Shang
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
| | - Yunxia Zhao
- Department of Basic Medical College, Bengbu Medical College, Bengbu, Anhui, China
| | - Shujing Li
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
| | - Yu Gao
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, Anhui, China
| | - Yuanyuan Wang
- School of Life Science, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, China
- Anhui Province Key Laboratory of Translational Cancer Research, Bengbu Medical College, No. 2600 Donghai Road, Bengbu, Anhui, China
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2
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Ding N, Xu X, Wang Y, Li H, Cao Y, Zheng L. Contribution of prognostic ferroptosis-related subtypes classification and hub genes of sepsis. Transpl Immunol 2022; 74:101660. [PMID: 35787932 DOI: 10.1016/j.trim.2022.101660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/27/2022] [Accepted: 06/28/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND Sepsis in patients is a great threat to human health due to its high incidence rate, its rapid and unpredictable progression, as well as it is difficult to treat, and it has poor prognosis. Ferroptosis is a newly discovered type of cell death characterized by the iron-dependent peroxide aggregation. Furthermore, ferroptosis is different from other forms of cell death, namely apoptosis, necrosis, pyroptosis and autophagy. Our study investigated the role of ferroptosis-related genes in sepsis. METHODS The GSE65682 dataset from the Gene Expression Omnibus (GEO) database was used to screen ferroptosis-related genes associated with sepsis, and the GSE134347 dataset for the external validation of selected hub genes. The univariate Cox regression analysis, Kaplan-Meier (K-M) survival analysis and weighted gene co-expression network analysis (WGCNA) were used to identify hub genes. Evaluation of the immune cell infiltration in sepsis was used to explain the immune heterogeneity among the cell subtypes. Gene set variation analysis (GSVA) and transcriptional regulatory analysis of selected hub genes further elucidated the probable mechanism of ferroptosis-related genes associated with prognosis in sepsis. Finally, we constructed a competing endogenous RNA (ceRNA) network model. RESULTS A total of 479 RNA-seq data points were used for analysis, including 365 samples from patients who survived sepsis and 114 samples from patients who succumbed to sepsis from the available GSE65682 dataset. Consequently, the univariate Cox regression analysis and consensus clustering analysis divide all 479 sepsis samples into two clusters of "survivals" vs. "non-survivals". Following complex analysis were identified as the most important ferroptosis-related genes. Indeed, the WGCNA and K-M analyses associated the expression patterns of NEDD4L and SIAH2 hub genes as the best prognosis for the survival of sepsis (p < 0.05). The expression trend was also consistent with the survival trend of the NEDD4L and SIAH2 hub genes by the external validation of GSE134347 (p < 0.05). Immune cell infiltration analysis indicated that the types and numbers of different immune cells vary among different subtypes and NEDD4L and SIAH2 hub genes. For example, NEDD4L and SIAH2 gene expression had a positive correlation with M0 macrophages and a negative correlation with neutrophils (p > 0.05). Finally, analysis of two hub genes and transcription factors (TFs) showed that 71 TFs were predicted to be related to NEDD4L while 64 TFs to SIAH2 by the Cistrome DB online database. CONCLUSION We suggest that NEDD4L and SIAH2 hub genes are involved in the ferroptosis-associated sepsis. The pattern of NEDD4L and SIAH2 expression in patients undergoing sepsis may have prognostic potential for the severity of sepsis and eventually for patients' survival.
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Affiliation(s)
- Ni Ding
- Department of Anesthesiology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518071, Guangdong, China
| | - Xiangzhao Xu
- Department of Anesthesiology, The Fifth People's Hospital of Ningxia, Shizuishan 753000, Ningxia, China
| | - Yuting Wang
- Department of Anesthesiology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518071, Guangdong, China
| | - Huiting Li
- Department of Anesthesiology, Sun Yat-Sen University Cancer Center, Guangzhou 753000, Guangdong, China
| | - Yuling Cao
- Department of Anesthesiology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518071, Guangdong, China
| | - Lei Zheng
- Department of Anesthesiology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen 518071, Guangdong, China.
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Pujar M, Vastrad B, Kavatagimath S, Vastrad C, Kotturshetti S. Identification of candidate biomarkers and pathways associated with type 1 diabetes mellitus using bioinformatics analysis. Sci Rep 2022; 12:9157. [PMID: 35650387 PMCID: PMC9160069 DOI: 10.1038/s41598-022-13291-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 05/16/2022] [Indexed: 12/14/2022] Open
Abstract
Type 1 diabetes mellitus (T1DM) is a metabolic disorder for which the underlying molecular mechanisms remain largely unclear. This investigation aimed to elucidate essential candidate genes and pathways in T1DM by integrated bioinformatics analysis. In this study, differentially expressed genes (DEGs) were analyzed using DESeq2 of R package from GSE162689 of the Gene Expression Omnibus (GEO). Gene ontology (GO) enrichment analysis, REACTOME pathway enrichment analysis, and construction and analysis of protein–protein interaction (PPI) network, modules, miRNA-hub gene regulatory network and TF-hub gene regulatory network, and validation of hub genes were performed. A total of 952 DEGs (477 up regulated and 475 down regulated genes) were identified in T1DM. GO and REACTOME enrichment result results showed that DEGs mainly enriched in multicellular organism development, detection of stimulus, diseases of signal transduction by growth factor receptors and second messengers, and olfactory signaling pathway. The top hub genes such as MYC, EGFR, LNX1, YBX1, HSP90AA1, ESR1, FN1, TK1, ANLN and SMAD9 were screened out as the critical genes among the DEGs from the PPI network, modules, miRNA-hub gene regulatory network and TF-hub gene regulatory network. Receiver operating characteristic curve (ROC) analysis confirmed that these genes were significantly associated with T1DM. In conclusion, the identified DEGs, particularly the hub genes, strengthen the understanding of the advancement and progression of T1DM, and certain genes might be used as candidate target molecules to diagnose, monitor and treat T1DM.
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Affiliation(s)
- Madhu Pujar
- Department of Pediatrics, J J M Medical College, Davangere, Karnataka, 577004, India
| | - Basavaraj Vastrad
- Department of Pharmaceutical Chemistry, K.L.E. College of Pharmacy, Gadag, Karnataka, 582101, India
| | - Satish Kavatagimath
- Department of Pharmacognosy, K.L.E. College of Pharmacy, Belagavi, Karnataka, 590010, India
| | - Chanabasayya Vastrad
- Biostatistics and Bioinformatics, Chanabasava Nilaya, Bharthinagar, Dharwad, Karnataka, 580001, India.
| | - Shivakumar Kotturshetti
- Biostatistics and Bioinformatics, Chanabasava Nilaya, Bharthinagar, Dharwad, Karnataka, 580001, India
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Dang TN, Tiongco RP, Brown LM, Taylor JL, Lyons JM, Lau FH, Floyd ZE. Expression of the preadipocyte marker ZFP423 is dysregulated between well-differentiated and dedifferentiated liposarcoma. BMC Cancer 2022; 22:300. [PMID: 35313831 PMCID: PMC8939188 DOI: 10.1186/s12885-022-09379-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 03/04/2022] [Indexed: 11/19/2022] Open
Abstract
Background Well-differentiated and dedifferentiated liposarcomas are rare soft tissue tumors originating in adipose tissue that share genetic abnormalities but have significantly different metastatic potential. Dedifferentiated liposarcoma (DDLPS) is highly aggressive and has an overall 5-year survival rate of 30% as compared to 90% for well-differentiated liposarcoma (WDLPS). This discrepancy may be connected to their potential to form adipocytes, where WDLPS is adipogenic but DDLPS is adipogenic-impaired. Normal adipogenesis requires Zinc Finger Protein 423 (ZFP423), a transcriptional coregulator of Perixosome Proliferator Activated Receptor gamma (PPARG2) mRNA expression that defines committed preadipocytes. Expression of ZFP423 in preadipocytes is promoted by Seven-In-Absentia Homolog 2 (SIAH2)-mediated degradation of Zinc Finger Protein 521 (ZFP521). This study investigated the potential role of ZFP423, SIAH2 and ZFP521 in the adipogenic potential of WDLPS and DDLPS. Methods Human WDLPS and DDLPS fresh and paraffin-embedded tissues were used to assess the gene and protein expression of proadipogenic regulators. In parallel, normal adipose tissue stromal cells along with WDLPS and DDLPS cell lines were cultured, genetically modified, and induced to undergo adipogenesis in vitro. Results Impaired adipogenic potential in DDLPS was associated with reduced ZFP423 protein levels in parallel with reduced PPARG2 expression, potentially involving regulation of ZFP521. SIAH2 protein levels did not define a clear distinction related to adipogenesis in these liposarcomas. However, in primary tumor specimens, SIAH2 mRNA was consistently upregulated in DDLPS compared to WDLPS when assayed by fluorescence in situ hybridization or real-time PCR. Conclusions These data provide novel insights into ZFP423 expression in adipogenic regulation between WDLPS and DDLPS adipocytic tumor development. The data also introduces SIAH2 mRNA levels as a possible molecular marker to distinguish between WDLPS and DDLPS. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-022-09379-6.
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Affiliation(s)
- Thanh N Dang
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, 70808, USA
| | - Rafael P Tiongco
- Tulane University School of Medicine, New Orleans, Louisiana, 70118, USA
| | - Loren M Brown
- Department of Surgery, Louisiana State University Health Science Center, New Orleans, Louisiana, 70112, USA
| | - Jessica L Taylor
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, 70808, USA
| | - John M Lyons
- Our Lady of the Lake Medical Center, Baton Rouge, Louisiana, 70808, USA
| | - Frank H Lau
- Department of Surgery, Louisiana State University Health Science Center, New Orleans, Louisiana, 70112, USA.
| | - Z Elizabeth Floyd
- Pennington Biomedical Research Center, Baton Rouge, Louisiana, 70808, USA.
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Spies LML, Verhoog NJD, Louw A. Acquired Glucocorticoid Resistance Due to Homologous Glucocorticoid Receptor Downregulation: A Modern Look at an Age-Old Problem. Cells 2021; 10:2529. [PMID: 34685511 PMCID: PMC8533966 DOI: 10.3390/cells10102529] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 09/15/2021] [Accepted: 09/21/2021] [Indexed: 12/11/2022] Open
Abstract
For over 70 years, the unique anti-inflammatory properties of glucocorticoids (GCs), which mediate their effects via the ligand-activated transcription factor, the glucocorticoid receptor alpha (GRα), have allowed for the use of these steroid hormones in the treatment of various autoimmune and inflammatory-linked diseases. However, aside from the onset of severe side-effects, chronic GC therapy often leads to the ligand-mediated downregulation of the GRα which, in turn, leads to a decrease in GC sensitivity, and effectively, the development of acquired GC resistance. Although the ligand-mediated downregulation of GRα is well documented, the precise factors which influence this process are not well understood and, thus, the development of an acquired GC resistance presents an ever-increasing challenge to the pharmaceutical industry. Recently, however, studies have correlated the dimerization status of the GRα with its ligand-mediated downregulation. Therefore, the current review will be discussing the major role-players in the homologous downregulation of the GRα pool, with a specific focus on previously reported GC-mediated reductions in GRα mRNA and protein levels, the molecular mechanisms through which the GRα functional pool is maintained and the possible impact of receptor conformation on GC-mediated GRα downregulation.
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Affiliation(s)
| | | | - Ann Louw
- Department of Biochemistry, Stellenbosch University, Van de Byl Street, Stellenbosch 7200, South Africa; (L.-M.L.S.); (N.J.D.V.)
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Meng Y, Qiu L, Zhang S, Han J. The emerging roles of E3 ubiquitin ligases in ovarian cancer chemoresistance. CANCER DRUG RESISTANCE (ALHAMBRA, CALIF.) 2021; 4:365-381. [PMID: 35582023 PMCID: PMC9019267 DOI: 10.20517/cdr.2020.115] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 12/24/2022]
Abstract
Epithelial cancer of the ovary exhibits the highest mortality rate of all gynecological malignancies in women today, since the disease is often diagnosed in advanced stages. While the treatment of cancer with specific chemical agents or drugs is the favored treatment regimen, chemotherapy resistance greatly impedes successful ovarian cancer chemotherapy. Thus, chemoresistance becomes one of the most critical clinical issues confronted when treating patients with ovarian cancer. Convincing evidence hints that dysregulation of E3 ubiquitin ligases is a key factor in the development and maintenance of ovarian cancer chemoresistance. This review outlines recent advancement in our understanding of the emerging roles of E3 ubiquitin ligases in ovarian cancer chemoresistance. We also highlight currently available inhibitors targeting E3 ligase activities and discuss their potential for clinical applications in treating chemoresistant ovarian cancer patients.
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Affiliation(s)
- Yang Meng
- Research Laboratory of Cancer Epigenetics and Genomics, Department of General Surgery, Frontiers Science Center for Disease-related Molecular Network, Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
- Yang Meng and Lei Qiu equally contributed to this manuscript
| | - Lei Qiu
- Research Laboratory of Cancer Epigenetics and Genomics, Department of General Surgery, Frontiers Science Center for Disease-related Molecular Network, Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
- Yang Meng and Lei Qiu equally contributed to this manuscript
| | - Su Zhang
- Research Laboratory of Cancer Epigenetics and Genomics, Department of General Surgery, Frontiers Science Center for Disease-related Molecular Network, Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Junhong Han
- Research Laboratory of Cancer Epigenetics and Genomics, Department of General Surgery, Frontiers Science Center for Disease-related Molecular Network, Cancer Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, China
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7
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Dang TN, Taylor JL, Kilroy G, Yu Y, Burk DH, Floyd ZE. SIAH2 is Expressed in Adipocyte Precursor Cells and Interacts with EBF1 and ZFP521 to Promote Adipogenesis. Obesity (Silver Spring) 2021; 29:98-107. [PMID: 33155406 PMCID: PMC7902405 DOI: 10.1002/oby.23013] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Expression of zinc finger protein 423 (ZFP423), a key proadipogenic transcription factor in adipocyte precursor cells, is regulated by interaction of the proadipogenic early B-cell factor 1 (EBF1) and antiadipogenic ZFP521. The ubiquitin ligase seven-in-absentia homolog 2 (SIAH2) targets ZFP521 for degradation. This study asked whether SIAH2 is expressed in adipocyte precursor cells and whether SIAH2 interacts with ZFP521 and EBF1 to regulate ZFP521 protein levels during adipogenesis. METHODS SIAH2 expression in precursor cells was assessed in primary cells and tissues from wild-type and SIAH2 null mice fed a control or high-fat diet. Primary cells, 3T3-L1 preadipocytes, and HEK293T cells were used to analyze Siah2, Ebf1, and Zfp521 expression and SIAH2-mediated changes in ZFP521 and EBF1 protein levels. RESULTS Siah2 is expressed in platelet-derived growth factor receptor α (PDGFRα)+ and stem cell antigen-1 (SCA1)+ adipocyte precursor cells. SIAH2 depletion reduces Ebf1 gene expression and increases EBF1 protein levels in early but not late adipogenesis. In early adipogenesis, SIAH2 forms a protein complex with EBF1 and ZFP521 to enhance SIAH2-mediated ubiquitylation and degradation of ZFP521 while increasing EBF1 protein levels. CONCLUSIONS Siah2 is expressed in PDGFRα+ adipocyte precursor cells and is linked to precursor cell commitment to adipogenesis by interacting with EBF1 and ZFP521 proteins to target the antiadipogenic ZFP521 for degradation.
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Affiliation(s)
- Thanh N Dang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Jessica L Taylor
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Gail Kilroy
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Yongmei Yu
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - David H Burk
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Z Elizabeth Floyd
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
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The Ubiquitin Ligase SIAH2 Negatively Regulates Glucocorticoid Receptor Activity and Abundance. Biomedicines 2020; 9:biomedicines9010022. [PMID: 33396678 PMCID: PMC7823448 DOI: 10.3390/biomedicines9010022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/22/2020] [Accepted: 12/24/2020] [Indexed: 11/25/2022] Open
Abstract
Glucocorticoids are clinically essential drugs used routinely to control inflammation. However, a host of metabolic side effects manifests upon usage beyond a few days. In the present study, we tested the hypothesis that seven-in-absentia mammalian homolog-2 (SIAH2), a ubiquitin ligase that regulates adipogenesis, is important for controlling adipocyte size, inflammation, and the ability of adipose tissue to expand in response to a glucocorticoid challenge. Using mice with global deletion of SIAH2 exposed or not to corticosterone, we found that adipocytes are larger in response to glucocorticoids in the absence of SIAH2. In addition, SIAH2 regulates glucocorticoid receptor (GR) transcriptional activity and total GR protein abundance. Moreover, these studies reveal that there is an increased expression of genes involved in fibrosis and inflammatory signaling pathways found in white adipose tissue in response to glucocorticoids in the absence of SIAH2. In summary, this is the first study to identify a role for SIAH2 to regulate transcriptional activity and abundance of the GR, which leads to alterations in adipose tissue size and gene expression during in vivo exposure to glucocorticoids.
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Abstract
Adipose, or fat, tissue (AT) was once considered an inert tissue that primarily existed to store lipids, and was not historically recognized as an important organ in the regulation and maintenance of health. With the rise of obesity and more rigorous research, AT is now recognized as a highly complex metabolic organ involved in a host of important physiological functions, including glucose homeostasis and a multitude of endocrine capabilities. AT dysfunction has been implicated in several disease states, most notably obesity, metabolic syndrome and type 2 diabetes. The study of AT has provided useful insight in developing strategies to combat these highly prevalent metabolic diseases. This review highlights the major functions of adipose tissue and the consequences that can occur when disruption of these functions leads to systemic metabolic dysfunction.
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Affiliation(s)
- Innocence Harvey
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - Anik Boudreau
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA
| | - Jacqueline M Stephens
- Adipocyte Biology Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.,Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
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Li H, Xu X, Wang D, Zeng L, Li B, Zhang Y, Su S, Wei L, You H, Fang Y, Wang Y, Liu Y. miR-146b-5p regulates bone marrow mesenchymal stem cell differentiation by SIAH2/PPARγ in aplastic anemia children and benzene-induced aplastic anemia mouse model. Cell Cycle 2020; 19:2460-2471. [PMID: 32840137 PMCID: PMC7553565 DOI: 10.1080/15384101.2020.1807081] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 07/16/2020] [Accepted: 07/23/2020] [Indexed: 12/26/2022] Open
Abstract
This study aimed to reveal the mechanism of miR-146b-5p in the differentiation of bone marrow mesenchymal stem cells (BMSCs) derived from children with aplastic anemia (AA). Here, we found that miR-146b-5p was highly expressed in BMSCs from children with AA, and the BMSCs surface markers expressions in BMSCs derived from children with AA and the healthy controls exerted no significant differences. Besides, the overexpression of miR-146b-5p in normal human-derived BMSCs promoted the adipogenic differentiation of BMSCs. Furthermore, miR-146b-5p negatively regulated SIAH2 luciferase activity, and the interference with miR-146b-5p reduced the stability of PPARγ protein and inhibited SIAH2-mediated ubiquitination of PPARγ protein. Besides, the interference with miR-146b-5p was beneficial for ameliorating AA in a mouse model of AA. Overall, our results found that miR-146b-5p was highly expressed in BMSCs from children with AA, and our further studies indicated that miR-146b-5p improved AA via promoting SIAH2-mediated ubiquitination of PPARγ protein.
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Affiliation(s)
- Huanhuan Li
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xueju Xu
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Dao Wang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Li Zeng
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Bai Li
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yuan Zhang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Shufang Su
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Linlin Wei
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Hongliang You
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yingqi Fang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yingchao Wang
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yufeng Liu
- Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Dou H, Duan Y, Zhang X, Yu Q, Di Q, Song Y, Li P, Gong Y. Aryl hydrocarbon receptor (AhR) regulates adipocyte differentiation by assembling CRL4B ubiquitin ligase to target PPARγ for proteasomal degradation. J Biol Chem 2019; 294:18504-18515. [PMID: 31653699 DOI: 10.1074/jbc.ra119.009282] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 10/16/2019] [Indexed: 12/17/2022] Open
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) is the central regulator of adipogenesis, and its dysregulation is linked to obesity and metabolic diseases. Identification of the factors that regulate PPARγ expression and activity is therefore crucial for combating obesity. Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor with a known role in xenobiotic detoxification. Recent studies have suggested that AhR also plays essential roles in energy metabolism. However, the detailed mechanisms remain unclear. We previously reported that experiments with adipocyte-specific Cullin 4b (Cul4b)-knockout mice showed that CUL4B suppresses adipogenesis by targeting PPARγ. Here, using immunoprecipitation, ubiquitination, real-time PCR, and GST-pulldown assays, we report that AhR functions as the substrate receptor in CUL4B-RING E3 ubiquitin ligase (CRL4B) complex and is required for recruiting PPARγ. AhR overexpression reduced PPARγ stability and suppressed adipocyte differentiation, and AhR knockdown stimulated adipocyte differentiation in 3T3-L1 cells. Furthermore, we found that two lysine sites on residues 268 and 293 in PPARγ are targeted for CRL4B-mediated ubiquitination, indicating cross-talk between acetylation and ubiquitination. Our findings establish a critical role of AhR in regulating PPARγ stability and suggest that the AhR-PPARγ interaction may represent a potential therapeutic target for managing metabolic diseases arising from PPARγ dysfunction.
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Affiliation(s)
- Hao Dou
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Yuyao Duan
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Xiaohui Zhang
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Qian Yu
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Qian Di
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Yu Song
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Peishan Li
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China
| | - Yaoqin Gong
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Shandong University, Jinan, Shandong 250012, China.
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12
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Ghosh S, Taylor JL, Mendoza TM, Dang T, Burk DH, Yu Y, Kilroy G, Floyd ZE. Siah2 modulates sex-dependent metabolic and inflammatory responses in adipose tissue to a high-fat diet challenge. Biol Sex Differ 2019; 10:19. [PMID: 30987673 PMCID: PMC6466809 DOI: 10.1186/s13293-019-0233-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 03/31/2019] [Indexed: 02/08/2023] Open
Abstract
Background The obesity-related risk of developing metabolic syndrome is higher in males than in females of reproductive age, likely due to estrogen-mediated reduced adipose tissue inflammation and fibrosis with hypertrophied adipocytes. Depletion of the ubiquitin ligase Siah2 reduced white adipose tissue inflammation and improved glucose metabolism in obese male mice. Siah2 is a transcriptional target of estrogen, but data is lacking about the effect of Siah2 on adipose tissue of females. We therefore evaluated the impact of Siah2 deficiency on white and brown adipose tissue in females of reproductive age. Methods Body composition, adipose tissue morphology, brown adipose tissue gene, and protein expression and adipocyte sizing were evaluated in wild-type and Siah2KO female and male mice fed a low-fat or high-fat diet. Glucose and insulin tolerance, fasting glucose, insulin, fatty acids and triglycerides, and gene expression of inflammation markers in perigonadal fat were evaluated in wild-type and Siah2KO female mice. Microarray analysis of brown fat gene expression was carried out in both sexes. Statistical analysis was assessed by unpaired two-tailed t test and repeated measures ANOVA. Results Siah2 deficiency improves glucose and insulin tolerance in the presence of hypertrophied white adipocytes in high-fat-fed female mice with percent fat comparable to male mice. While previous studies showed Siah2KO reduces the white adipose tissue inflammatory response in male mice, the response in females is biased toward the upregulation of M2-like markers in white adipose tissue. In contrast, loss of Siah2 leads to increased whitening of brown fat in males, but not in females. This corresponded to increased expression of markers of inflammation (F4/80, Ccl2) and thermogenic genes (Pgc1alpha, Dio2, Ucp-1) and proteins (PGC-1α, UCP-1) in females. Contrary to expectations, increased expression of thermogenic markers in females was coupled with a downregulation of ERalpha and ERRgamma protein levels. Conclusions The most striking sex-related effect of Siah2 deficiency is reduced whitening of brown fat in high-fat-fed females. Protection from accumulating unilocular adipocytes in the brown fat corresponds to increased expression of thermogenic genes and proteins in female, but not in male mice. These results raise the possibility that Siah2 contributes to the estrogen-related effects on brown fat function in males and females. Electronic supplementary material The online version of this article (10.1186/s13293-019-0233-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sujoy Ghosh
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA.,Cardiovascular and Metabolic Disease Program and Center for Computational Biology, Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Jessica L Taylor
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Tamra M Mendoza
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Thanh Dang
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - David H Burk
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Yongmei Yu
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
| | - Gail Kilroy
- Pennington Biomedical Research Center, Baton Rouge, LA, 70808, USA
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13
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Lin H, Lunetta KL, Zhao Q, Rong J, Benjamin EJ, Mendelson MM, Joehanes R, Levy D, Larson MG, Murabito JM. Transcriptome-wide association study of inflammatory biologic age. Aging (Albany NY) 2017; 9:2288-2301. [PMID: 29135455 PMCID: PMC5723687 DOI: 10.18632/aging.101321] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/02/2017] [Indexed: 05/16/2023]
Abstract
Chronic low grade inflammation is a fundamental mechanism of aging. We estimated biologic age using nine biomarkers from diverse inflammatory pathways and we hypothesized that genes associated with inflammatory biological age would provide insights into human aging. In Framingham Offspring Study participants at examination 8 (2005 to 2008), we used the Klemera-Doubal method to estimate inflammatory biologic age and we computed the difference (∆Age) between biologic age and chronologic age. Gene expression in whole blood was measured using the Affymetrix Human Exon 1.0 ST Array. We used linear mixed effect models to test associations between inflammatory ∆Age and gene expression (dependent variable) adjusting for age, sex, imputed cell counts, and technical covariates. Our study sample included 2386 participants (mean age 67A±9 years, 55% women). There were 448 genes significantly were associated with inflammatory ∆Age (P<2.8x10-6), 302 genes were positively associated and 146 genes were negatively associated. Pathway analysis among the identified genes highlighted the NOD-like receptor signaling and ubiquitin mediated proteolysis pathways. In summary, we identified 448 genes that were significantly associated with inflammatory biologic age. Future functional characterization may identify molecular interventions to delay aging and prolong healthspan in older adults.
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Affiliation(s)
- Honghuang Lin
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Section of Computational Biomedicine, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
| | - Kathryn L. Lunetta
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA
| | - Qiang Zhao
- Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA
| | - Jian Rong
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Emelia J. Benjamin
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Section of Cardiovascular Medicine and Preventive Medicine, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
- Department of Epidemiology, Boston University School of Public Health, Boston, MA 02118, USA
| | - Michael M. Mendelson
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Population Sciences Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Department of Cardiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Roby Joehanes
- Hebrew SeniorLife, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel Levy
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Population Sciences Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Martin G. Larson
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA
| | - Joanne M. Murabito
- National Heart Lung and Blood Institute's and Boston University's Framingham Heart Study, Framingham, MA 01702, USA
- Section of General Internal Medicine, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA
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14
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Mota de Sá P, Richard AJ, Hang H, Stephens JM. Transcriptional Regulation of Adipogenesis. Compr Physiol 2017; 7:635-674. [PMID: 28333384 DOI: 10.1002/cphy.c160022] [Citation(s) in RCA: 246] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Adipocytes are the defining cell type of adipose tissue. Once considered a passive participant in energy storage, adipose tissue is now recognized as a dynamic organ that contributes to several important physiological processes, such as lipid metabolism, systemic energy homeostasis, and whole-body insulin sensitivity. Therefore, understanding the mechanisms involved in its development and function is of great importance. Adipocyte differentiation is a highly orchestrated process which can vary between different fat depots as well as between the sexes. While hormones, miRNAs, cytoskeletal proteins, and many other effectors can modulate adipocyte development, the best understood regulators of adipogenesis are the transcription factors that inhibit or promote this process. Ectopic expression and knockdown approaches in cultured cells have been widely used to understand the contribution of transcription factors to adipocyte development, providing a basis for more sophisticated in vivo strategies to examine adipogenesis. To date, over two dozen transcription factors have been shown to play important roles in adipocyte development. These transcription factors belong to several families with many different DNA-binding domains. While peroxisome proliferator-activated receptor gamma (PPARγ) is undoubtedly the most important transcriptional modulator of adipocyte development in all types of adipose tissue, members of the CCAAT/enhancer-binding protein, Krüppel-like transcription factor, signal transducer and activator of transcription, GATA, early B cell factor, and interferon-regulatory factor families also regulate adipogenesis. The importance of PPARγ activity is underscored by several covalent modifications that modulate its activity and its ability to modulate adipocyte development. This review will primarily focus on the transcriptional control of adipogenesis in white fat cells and on the mechanisms involved in this fine-tuned developmental process. © 2017 American Physiological Society. Compr Physiol 7:635-674, 2017.
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Affiliation(s)
- Paula Mota de Sá
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Allison J Richard
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Hardy Hang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
| | - Jacqueline M Stephens
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, USA
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15
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Li P, Song Y, Zan W, Qin L, Han S, Jiang B, Dou H, Shao C, Gong Y. Lack of CUL4B in Adipocytes Promotes PPARγ-Mediated Adipose Tissue Expansion and Insulin Sensitivity. Diabetes 2017; 66:300-313. [PMID: 27899484 DOI: 10.2337/db16-0743] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 11/05/2016] [Indexed: 11/13/2022]
Abstract
Obesity and obesity-associated diseases are linked to dysregulation of the peroxisome proliferator-activated receptor γ (PPARγ) signaling pathway. Identification of the factors that regulate PPARγ expression and activity is crucial for combating obesity. However, the ubiquitin E3 ligases that target PPARγ for proteasomal degradation have been rarely identified, and their functions in vivo have not been characterized. Here we report that CUL4B-RING E3 ligase (CRL4B) negatively regulates PPARγ by promoting its polyubiquitination and proteasomal degradation. Depletion of CUL4B led to upregulation of PPARγ-regulated genes and facilitated adipogenesis. Adipocyte-specific Cul4b knockout (AKO) mice being fed a high-fat diet exhibited increased body fat accumulation that was mediated by increased adipogenesis. However, AKO mice showed improved metabolic phenotypes, including increased insulin sensitivity and glucose tolerance. Correspondingly, there was a decreased inflammatory response in adipose tissues of AKO mice. Genetic inhibition of CUL4B thus appears to phenocopy the beneficial effects of PPARγ agonists. Collectively, this study establishes a critical role of CRL4B in the regulation of PPARγ stability and insulin sensitivity and suggests that CUL4B could be a potential therapeutic target for combating obesity and metabolic syndromes.
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Affiliation(s)
- Peishan Li
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Yu Song
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Wenying Zan
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Liping Qin
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Shuang Han
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Baichun Jiang
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Hao Dou
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Changshun Shao
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
| | - Yaoqin Gong
- The Key Laboratory of Experimental Teratology, Ministry of Education and Department of Molecular Medicine and Genetics, Shandong University School of Medicine, Jinan, Shandong, People's Republic of China
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16
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C-terminus of HSC70-Interacting Protein (CHIP) Inhibits Adipocyte Differentiation via Ubiquitin- and Proteasome-Mediated Degradation of PPARγ. Sci Rep 2017; 7:40023. [PMID: 28059128 PMCID: PMC5216347 DOI: 10.1038/srep40023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 12/01/2016] [Indexed: 12/30/2022] Open
Abstract
PPARγ (Peroxisome proliferator-activated receptor γ) is a nuclear receptor involved in lipid homeostasis and related metabolic diseases. Acting as a transcription factor, PPARγ is a master regulator for adipocyte differentiation. Here, we reveal that CHIP (C-terminus of HSC70-interacting protein) suppresses adipocyte differentiation by functioning as an E3 ligase of PPARγ. CHIP directly binds to and induces ubiquitylation of the PPARγ protein, leading to proteasome-dependent degradation. Stable overexpression or knockdown of CHIP inhibited or promoted adipogenesis, respectively, in 3T3-L1 cells. On the other hand, a CHIP mutant defective in E3 ligase could neither regulate PPARγ protein levels nor suppress adipogenesis, indicating the importance of CHIP-mediated ubiquitylation of PPARγ in adipocyte differentiation. Lastly, a CHIP null embryo fibroblast exhibited augmented adipocyte differentiation with increases in PPARγ and its target protein levels. In conclusion, CHIP acts as an E3 ligase of PPARγ, suppressing PPARγ-mediated adipogenesis.
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17
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Kilroy G, Burk DH, Floyd ZE. Siah2 Protein Mediates Early Events in Commitment to an Adipogenic Pathway. J Biol Chem 2016; 291:27289-27297. [PMID: 27864366 DOI: 10.1074/jbc.m116.744672] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 11/14/2016] [Indexed: 11/06/2022] Open
Abstract
Adipose tissue expansion occurs by increasing the size of existing adipocytes or by increasing the number of adipocytes via adipogenesis. Adipose tissue dysfunction in obesity is associated with adipocyte hypertrophy and impaired adipogenesis. We recently demonstrated that deletion of the ubiquitin ligase Siah2 is associated with enlarged adipocytes in lean or obese mice. In this study, we find that adipogenesis is impaired in 3T3-L1 preadipocytes stably transfected with Siah2 shRNA and that overexpression of Siah2 in non-precursor fibroblasts promotes adipogenesis. In the 3T3-L1 model, loss of Siah2 is associated with sustained β-catenin expression post-induction, but depletion of β-catenin only partially restores PPARγ expression and adipocyte formation. Using wild-type and Siah2-/- adipose tissue and adipose stromal vascular cells, we observe that Siah2 influences the expression of several factors that control adipogenesis, including Wnt pathway genes, β-catenin, Zfp432, and Bmp-4 Consistent with increased β-catenin levels in shSiah2 preadipocytes, Wnt10b is elevated in Siah2-/- adipose tissue and remains elevated in Siah2-/- primary stromal cells after addition of the induction mixture. However, addition of BMP-4 to Siah2-/- stromal cells reduces Wnt10b expression, reduces Zfp521 protein levels, and increases expression of Zfp423, a transcriptional regulator of peroxisome proliferator-activated receptor γ expression that controls commitment to adipogenesis and is repressed by Zfp521. These results indicate that Siah2 acts upstream of BMP-4 to regulate factors that control the commitment of adipocyte progenitors to an adipogenic pathway. Our findings reveal an essential role for Siah2 in the early events that signal undifferentiated progenitor cells to become mature adipocytes.
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Affiliation(s)
- Gail Kilroy
- From the Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana 70808
| | - David H Burk
- From the Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana 70808
| | - Z Elizabeth Floyd
- From the Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana 70808
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18
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Ai L, Wang X, Chen Z, Lin Q, Su D, Xu Q, Wu C, Jiang X, Xu A, Fan Z. A20 reduces lipid storage and inflammation in hypertrophic adipocytes via p38 and Akt signaling. Mol Cell Biochem 2016; 420:73-83. [PMID: 27443844 DOI: 10.1007/s11010-016-2768-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 07/09/2016] [Indexed: 02/06/2023]
Abstract
Adipose tissue plays a vital role in the development of obesity and related disorders. Our previous study showed that A20, an ubiquitin-editing enzyme with anti-inflammation function, attenuated free fatty acids (FFAs)-induced lipid accumulation in nonalcoholic steatohepatitis. Here, we investigated A20 expression in adipose tissue of obese individuals and its effects on 3T3-L1 lipogenesis as well as the likely mechanisms underlying this process. By re-annotation of raw microarray data downloaded from Gene Expression Omnibus, we found that obese individuals showed significantly higher A20 mRNA levels in adipocytes. In vitro, A20 inhibited MCP-1 and IL-6 secretion in adipocytes. Forced expression of A20 resulted in decreased expression of key markers of lipogenesis and adipogenesis, such as sterol regulatory element binding protein 1c (SREBP-1c) and adipogenesis (aP2), leading to less lipids accumulation in differentiated 3T3-L1 cells. This process was concomitant with attenuated activation of p38 and Akt signaling. Our results suggest that A20 may have therapeutic potential for obesity and related diseases. The mechanisms involved the suppression of lipid storage and inflammation in adipocytes.
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Affiliation(s)
- Luoyan Ai
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- Division of Gastroenterology and Hepatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease; Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaohan Wang
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- The First Hospital of Jiaxing, Jiaxing, Zhejiang, China
| | - Zhiwei Chen
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- Division of Rheumatology, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Qing Lin
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
| | - Dazhi Su
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- Division of Gastroenterology and Hepatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease; Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, Shanghai Jiao Tong University, Shanghai, China
| | - Qingqing Xu
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- Division of Gastroenterology and Hepatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease; Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, Shanghai Jiao Tong University, Shanghai, China
| | - Changwei Wu
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- Division of Gastroenterology and Hepatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease; Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaoke Jiang
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China
- Division of Gastroenterology and Hepatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease; Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, Shanghai Jiao Tong University, Shanghai, China
| | - Antao Xu
- Division of Gastroenterology and Hepatology, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease; Key Laboratory of Gastroenterology & Hepatology, Ministry of Health, Shanghai Jiao Tong University, Shanghai, China
| | - Zhuping Fan
- Department of Health Manage Center, School of Medicine, Ren Ji Hospital, Shanghai Jiao Tong University, No. 160, Pujian Road, Shanghai, China.
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Yang XD, Xiang DX, Yang YY. Role of E3 ubiquitin ligases in insulin resistance. Diabetes Obes Metab 2016; 18:747-54. [PMID: 27097743 DOI: 10.1111/dom.12677] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/09/2016] [Accepted: 04/17/2016] [Indexed: 12/19/2022]
Abstract
E3 ubiquitin ligases are a large family of proteins that catalyse the ubiquitination of many proteins for degradation by the 26S proteasome. E3 ubiquitin ligases play pivotal roles in the process of insulin resistance and diabetes. In this review, we summarize the currently available studies to analyse the potential role of E3 ubiquitin ligases in the development of insulin resistance. We propose two mechanisms by which E3 ubiquitin ligases can affect the process of insulin resistance. First, E3 ubiquitin ligases directly degrade the insulin receptor, insulin receptor substrate and other key insulin signalling molecules via the UPS. Second, E3 ubiquitin ligases indirectly regulate insulin signalling by regulating pro-inflammatory mediators that are involved in the regulation of insulin signalling molecules, such as tumour necrosis factor-α, interleukin (IL)-6, IL-4, IL-13, IL-1β, monocyte chemoattractant protein-1 and hypoxia-inducible factor 1α. Determining the mechanism by which E3 ubiquitin ligases affect the development of insulin resistance can identify a novel strategy to protect against insulin resistance and diabetes.
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Affiliation(s)
- X-D Yang
- Department of Pharmacy, the Second Xiangya Hospital, Central South University, Changsha, China
| | - D-X Xiang
- Department of Pharmacy, the Second Xiangya Hospital, Central South University, Changsha, China
| | - Y-Y Yang
- Department of Pharmacy, the Second Xiangya Hospital, Central South University, Changsha, China
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