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Liu H, Hallauer Hastings M, Kitchen R, Xiao C, Baldovino Guerra JR, Kuznetsov A, Rosenzweig A. Beneficial Effects of Moderate Hepatic Activin A Expression on Metabolic Pathways, Inflammation, and Atherosclerosis. Arterioscler Thromb Vasc Biol 2023; 43:330-349. [PMID: 36453275 DOI: 10.1161/atvbaha.122.318138] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
BACKGROUND Atherosclerosis is an inflammatory vascular disease marked by hyperlipidemia and hematopoietic stem cell expansion. Activin A, a member of the Activin/GDF/TGFβ/BMP (growth/differentiation factor/transforming growth factor beta/bone morphogenetic protein) family is broadly expressed and increases in human atherosclerosis, but its functional effects in vivo in this context remain unclear. METHODS We studied LDLR-/- mice on a Western diet for 12 weeks and used adeno-associated viral vectors with a liver-specific TBG (thyroxine-binding globulin) promoter to express Activin A or GFP (control). Atherosclerotic lesions were analyzed by oil red staining. Blood lipid profiling was performed by high-performance liquid chromatography, and immune cells were evaluated by flow cytometry. Liver RNA-sequencing was performed to explore the underlying mechanisms. RESULTS Activin A expression decreased in both livers and aortae from LDLR-/- mice fed a Western diet compared with standard laboratory diet. Adenoassociated virus-TBG-Activin A increased Activin A hepatic expression ≈10-fold at 12 weeks; P<0.001) and circulating Activin A levels ≈2000 pg/ml versus ≈50 pg/ml; P<0.001, compared with controls). Hepatic Activin A expression decreased plasma total and LDL (low-density lipoprotein) cholesterol ≈60% and ≈40%, respectively), reduced inflammatory cells in aortae and proliferating hematopoietic stem cells in bone marrow, and reduced atherosclerotic lesion and necrotic core area in aortae. Activin A also attenuated liver steatosis and expression of the lipogenesis genes, Srebp1 and Srebp2. RNA sequencing revealed Activin A not only blocked expression of genes involved in hepatic de novo lipogenesis but also fatty acid uptake and liver inflammation. In addition, Activin A expressed in the liver also reduced white fat tissue accumulation, decreased adipocyte size, and improved glucose tolerance. CONCLUSIONS Our studies reveal hepatic Activin A expression reduces inflammation, hematopoietic stem cell expansion, liver steatosis, circulating cholesterol, and fat accumulation, which likely all contribute to the observed protection against atherosclerosis. The reduced Activin A observed in LDLR-/- mice on a Western diet seems maladaptive and deleterious for atherogenesis.
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Affiliation(s)
- Huan Liu
- Cardiovascular Research Center, Massachusetts General Hospital, and Harvard Medical School, Boston
| | | | - Robert Kitchen
- Cardiovascular Research Center, Massachusetts General Hospital, and Harvard Medical School, Boston
| | - Chunyang Xiao
- Cardiovascular Research Center, Massachusetts General Hospital, and Harvard Medical School, Boston
| | | | - Alexandra Kuznetsov
- Cardiovascular Research Center, Massachusetts General Hospital, and Harvard Medical School, Boston
| | - Anthony Rosenzweig
- Cardiovascular Research Center, Massachusetts General Hospital, and Harvard Medical School, Boston
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Elbaz M, Hadas R, Bilezikjian LM, Gershon E. Uterine Foxl2 regulates the adherence of the Trophectoderm cells to the endometrial epithelium. Reprod Biol Endocrinol 2018; 16:12. [PMID: 29415736 PMCID: PMC5804001 DOI: 10.1186/s12958-018-0329-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Accepted: 01/30/2018] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Forkhead Transcription Factor L2 (FOXL2) is a member of the forkhead family with important roles in reproduction. Recent studies showed that FOXL2 is expressed in human and bovine endometrium and that its levels fluctuate during pregnancy. In this study, we aimed at evaluating the expression and function of FOXL2 in embryo implantation. METHODS Mouse uteri at different days of pregnancy were isolated and analyzed for the expression and localization of FOXL2. A lentiviral strategy was further employed to either knockdown or overexpress FOXL2 in non-receptive human endometrial AN3-CA cells and in receptive Ishikawa cells, respectively. These genetically modified cells were compared to cells infected with a control lentivirus to determine the function of FOXL2 in trophectoderm cells adherence to Endometrial Epithelium was associated with the expression of genes known to be involved in acquisition of uterine receptivity. RESULTS We report that FOXL2 is expressed in both, the luminal epithelium and the myometrium of the mouse uterus and that its expression declines prior to implantation. We found that endometrial cells expressing low FOXL2 levels, either endogenous or genetically manipulated, were associated with a higher attachment rate of mouse blastocysts or human Jeg3 spheroids and mouse blastocysts. In accordance, low-FOXL2 levels were associated with changes in the expression level of components of the Wnt/Fzd and apoptotic pathways, both of which are involved in uterine receptivity. Furthermore, FOXL2 expression was inversely correlated with G-protein signaling protein 2 (Rgs2) and cytokine expression. CONCLUSIONS These results suggest that FOXL2 interferes with embryo attachment. Better understanding of the function of FOXL2 in the uterus would possibly suggest novel strategies for treatment of infertility attributed to repeated implantation failure.
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Affiliation(s)
- Michal Elbaz
- 0000 0001 0465 9329grid.410498.0Department of Ruminant Science, Agricultural Research Organization, 50250 Rishon LeZion, Israel
| | - Ron Hadas
- 0000 0004 0604 7563grid.13992.30Department of Biological Regulation, Weizmann Institute of Science, 76100 Rehovot, Israel
| | - Louise M. Bilezikjian
- 0000 0001 0662 7144grid.250671.7Clayton Foundation Laboratories for Peptide Biology and Laboratory of Neuronal Structure and Function, Salk Institute for Biological Studies, La Jolla, San Diego, CA 92037 USA
| | - Eran Gershon
- 0000 0001 0465 9329grid.410498.0Department of Ruminant Science, Agricultural Research Organization, 50250 Rishon LeZion, Israel
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Pegylated Interferon-α Modulates Liver Concentrations of Activin-A and Its Related Proteins in Normal Wistar Rat. Mediators Inflamm 2015; 2015:414207. [PMID: 26236109 PMCID: PMC4506924 DOI: 10.1155/2015/414207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 05/30/2015] [Accepted: 06/03/2015] [Indexed: 02/06/2023] Open
Abstract
Aims. To measure the expression of activin βA-subunit, activin IIA and IIB receptors, Smad4, Smad7, and follistatin in the liver and the liver and serum concentrations of mature activin-A and follistatin in normal rat following treatment with pegylated interferon-α (Peg-INF-α) and ribavirin (RBV). Materials and Methods. 40 male Wistar rats were divided equally into 4 groups: “control,” “Peg-only” receiving 4 injections of Peg-INF-α (6 µg/rat/week), “RBV-only” receiving ribavirin (4 mg/rat/day) orally, and “Peg & RBV” group receiving both drugs. The expression of candidate molecules in liver was measured by immunohistochemistry and quantitative PCR. The concentrations of mature proteins in serum and liver homogenate samples were measured using ELISA. Results. Peg-INF-α ± RBV altered the expression of all candidate molecules in the liver at the gene and protein levels (P < 0.05) and decreased activin-A and increased follistatin in serum and liver homogenates compared with the other groups (P < 0.05). There were also significant correlations between serum and liver activin-A and follistatin. Conclusion. Peg-INF-α modulates the hepatic production of activin-A and follistatin, which can be detected in serum. Further studies are needed to explore the role of Peg-INF-α on the production of activins and follistatin by the liver and immune cells.
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The effects of pegylated interferon-α and ribavirin on liver and serum concentrations of activin-A and follistatin in normal Wistar rat: a preliminary report. BMC Res Notes 2015; 8:265. [PMID: 26112013 PMCID: PMC4481076 DOI: 10.1186/s13104-015-1253-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 06/18/2015] [Indexed: 12/22/2022] Open
Abstract
Background Activin-A and follistatin regulate the liver and the immune system. Aims To measure the effects of treatment with pegylated-interferon-α (Peg-IFN-α) and ribavirin on the concentrations of mature activin-A and follistatin in serum and liver tissue homogenates in rats. Methods A total of 28 male Wistar rats were divided equally into four groups as follow: ‘Control group’ (n = 7), ‘PEG only group’ consisted of those that only received a weekly injection of Peg-IFN-α (6 µg/rat) for 4 weeks, ‘RBV only group’ received ribavirin only (4 mg/rat/day) orally for 35 days and the last group received both Peg-IFN-α and ribavirin ‘PEG & RBV group’. The concentrations of candidate proteins in serum and liver samples were measured using ELISA. Results Pegylated-interferon-α decreased activin-A and increased follistatin significantly in serum and liver of ‘PEG only’ and ‘PEG & RBV’ groups compared with the ‘Control’ and ‘RBV only’ groups (P < 0.05). There was no significant difference between the ‘RBV only’ and ‘Control’ groups (P > 0.05) in the concentrations of candidate proteins. A significant positive correlations between serum and liver activin-A (r = 0.727; P = 0.02 × 10−3) and follistatin (r = 0.540; P = 0.01) was also detected. Conclusion Pegylated-interferon-α modulates the production of activin-A and follistatin by the liver, which is reflected and can be detected at the serum level. Further studies are needed to explore the role of Peg-IFN-α based therapy on the production of activins and follistatin by the liver and immune cells.
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Fortin J, Ongaro L, Li Y, Tran S, Lamba P, Wang Y, Zhou X, Bernard DJ. Minireview: Activin Signaling in Gonadotropes: What Does the FOX say… to the SMAD? Mol Endocrinol 2015; 29:963-77. [PMID: 25942106 DOI: 10.1210/me.2015-1004] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The activins were discovered and named based on their abilities to stimulate FSH secretion and FSHβ (Fshb) subunit expression by pituitary gonadotrope cells. According to subsequent in vitro observations, activins also stimulate the transcription of the GnRH receptor (Gnrhr) and the activin antagonist, follistatin (Fst). Thus, not only do activins stimulate FSH directly, they have the potential to regulate both FSH and LH indirectly by modulating gonadotrope sensitivity to hypothalamic GnRH. Moreover, activins may negatively regulate their own actions by stimulating the production of one of their principal antagonists. Here, we describe our current understanding of the mechanisms through which activins regulate Fshb, Gnrhr, and Fst transcription in vitro. The activin signaling molecules SMAD3 and SMAD4 appear to partner with the winged-helix/forkhead transcription factor, forkhead box L2 (FOXL2), to regulate expression of all 3 genes. However, in vivo data paint a different picture. Although conditional deletion of Foxl2 and/or Smad4 in murine gonadotropes produces impairments in FSH synthesis and secretion as well as in pituitary Fst expression, Gnrhr mRNA levels are either unperturbed or increased in these animals. Surprisingly, gonadotrope-specific deletion of Smad3 alone or with Smad2 does not impair FSH production or fertility; however, mice harboring these mutations may express a DNA binding-deficient, but otherwise functional, SMAD3 protein. Collectively, the available data firmly establish roles for FOXL2 and SMAD4 in Fshb and Fst expression in gonadotrope cells, whereas SMAD3's role requires further investigation. Gnrhr expression, in contrast, appears to be FOXL2, SMAD4, and, perhaps, activin independent in vivo.
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Affiliation(s)
- Jérôme Fortin
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Luisina Ongaro
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Yining Li
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Stella Tran
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Pankaj Lamba
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Ying Wang
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Xiang Zhou
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
| | - Daniel J Bernard
- Department of Pharmacology and Therapeutics (J.F., L.O., Y.L., S.T., P.L., Y.W., X.Z., D.J.B.), McGill University, Montréal, Québec, Canada H3G 1Y6; The Campbell Family Cancer Research Institute (J.F.), Ontario Cancer Institute, University Health Network, Toronto, Ontario, Canada M5G 2C1; Diabetes Center (S.T.), Department of Medicine, University of California-San Francisco, San Francisco, California 94143; and Psychiatry (P.L.), St Mary Mercy Hospital, Livonia, Michigan 48154
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Refaat B, Ashshi AM, El-Shemi AG, Azhar E. Activins and Follistatin in Chronic Hepatitis C and Its Treatment with Pegylated-Interferon-α Based Therapy. Mediators Inflamm 2015; 2015:287640. [PMID: 25969625 PMCID: PMC4417604 DOI: 10.1155/2015/287640] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 02/27/2015] [Accepted: 02/27/2015] [Indexed: 12/12/2022] Open
Abstract
Pegylated-interferon-α based therapy for the treatment of chronic hepatitis C (CHC) is considered suboptimal as not all patients respond to the treatment and it is associated with several side effects that could lead to dose reduction and/or termination of therapy. The currently used markers to monitor the response to treatment are based on viral kinetics and their performance in the prediction of treatment outcome is moderate and does not combine accuracy and their values have several limitations. Hence, the development of new sensitive and specific predictor markers could provide a useful tool for the clinicians and healthcare providers, especially in the new era of interferon-free therapy, for the classification of patients according to their response to the standard therapy and only subscribing the novel directly acting antiviral drugs to those who are anticipated not to respond to the conventional therapy and/or have absolute contraindications for its use. The importance of activins and follistatin in the regulation of immune system, liver biology, and pathology has recently emerged. This review appraises the up-to-date knowledge regarding the role of activins and follistatin in liver biology and immune system and their role in the pathophysiology of CHC.
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Affiliation(s)
- Bassem Refaat
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al-'Abdiyah Campus, P. O. Box 7607, Makkah, Saudi Arabia
| | - Ahmed Mohamed Ashshi
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al-'Abdiyah Campus, P. O. Box 7607, Makkah, Saudi Arabia
| | - Adel Galal El-Shemi
- Laboratory Medicine Department, Faculty of Applied Medical Sciences, Umm Al-Qura University, Al-'Abdiyah Campus, P. O. Box 7607, Makkah, Saudi Arabia
- Department of Pharmacology, Faculty of Medicine, Assiut University, Assiut 6515, Egypt
| | - Esam Azhar
- Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Saudi Arabia
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Saudi Arabia
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Chai Y, Sun Y, Guo L, Li D, Ding Y. Investigating the role of introns in the regulation of regenerating gene 1 expression. Oncol Lett 2014; 9:875-880. [PMID: 25621062 PMCID: PMC4301469 DOI: 10.3892/ol.2014.2712] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 10/31/2014] [Indexed: 01/15/2023] Open
Abstract
Gastrin is a hormone that physiologically regulates gastric acid secretion and contributes to the maintenance of gastric epithelial architecture by regulating the expression of genes such as regenerating gene 1 (Reg1). Reg1 is involved in gastric carcinogenesis as an antiapoptotic factor. The current study explores the molecular mechanism of gastrin-regulated Reg1 expression in human gastric cancer cells. In total, five intron fragments of the Reg1 gene were cloned by polymerase chain reaction and inserted into luciferase reporter vector pGL3 to construct intron-luciferase reporter vectors. After confirmation by Xho I/Hind III digestion and DNA sequencing, the five constructs were transfected into the SGC7901 gastric cancer cell line. The luciferase activity of the cells transfected with each of the five constructs was detected following incubation without or with gastrin. The five intron fragments of Reg1 were also randomly labeled with digoxin as a probe, and nuclear proteins of gastric cancer cells were extracted following treatment with or without gastrin. Southwestern blotting was subsequently performed to detect transcription factors that bind to the introns. The results indicated that the luciferase activity was significantly higher in cells transfected with recombinant vectors containing introns 2, 3, 4 or 5 than that in the cells transfected with an empty vector (P<0.05). However, no statistically significant difference in luciferase activity was identified between cells transfected with pGL3-intron 1 and those transfected with pGL3-Basic (P>0.05). Following incubation with gastrin, no significant difference was identified (P>0.05). The five introns of Reg1 can bind a number of transcription factors and gastrin may affect this interaction. Introns 2–5 of Reg1 potentially have transcriptional control over gene expression in gastric cancer cells. In conclusion, gastrin may regulate the expression of the Reg1 gene via the interaction of the introns by binding to the transcription factors.
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Affiliation(s)
- Yurong Chai
- Department of Histology and Embryology, College of Basic Medicine, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Yun Sun
- Department of Histology and Embryology, College of Basic Medicine, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Linxia Guo
- Department of Histology and Embryology, College of Basic Medicine, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Dan Li
- Department of Histology and Embryology, College of Basic Medicine, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Yi Ding
- Department of Histology and Embryology, College of Basic Medicine, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
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Lin HS, Gong JN, Su R, Chen MT, Song L, Shen C, Wang F, Ma YN, Zhao HL, Yu J, Li WW, Huang LX, Xu XH, Zhang JW. miR-199a-5p inhibits monocyte/macrophage differentiation by targeting the activin A type 1B receptor gene and finally reducing C/EBPα expression. J Leukoc Biol 2014; 96:1023-35. [PMID: 25258381 DOI: 10.1189/jlb.1a0514-240r] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
miRNAs are short, noncoding RNAs that regulate expression of target genes at post-transcriptional levels and function in many important cellular processes, including differentiation, proliferation, etc. In this study, we observed down-regulation of miR-199a-5p during monocyte/macrophage differentiation of HL-60 and THP-1 cells, as well as human CD34(+) HSPCs. This down-regulation of miR-199a-5p resulted from the up-regulation of PU.1 that was demonstrated to regulate transcription of the miR-199a-2 gene negatively. Overexpression of miR-199a-5p by miR-199a-5p mimic transfection or lentivirus-mediated gene transfer significantly inhibited monocyte/macrophage differentiation of the cell lines or HSPCs. The mRNA encoding an ACVR1B was identified as a direct target of miR-199a-5p. Gradually increased ACVR1B expression level was detected during monocyte/macrophage differentiation of the leukemic cell lines and HSPCs, and knockdown of ACVR1B resulted in inhibition of monocyte/macrophage differentiation of HL-60 and THP-1 cells, which suggested that ACVR1B functions as a positive regulator of monocyte/macrophage differentiation. We demonstrated that miR-199a-5p overexpression or ACVR1B knockdown promoted proliferation of THP-1 cells through increasing phosphorylation of Rb. We also demonstrated that the down-regulation of ACVR1B reduced p-Smad2/3, which resulted in decreased expression of C/EBPα, a key regulator of monocyte/macrophage differentiation, and finally, inhibited monocyte/macrophage differentiation.
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Affiliation(s)
- Hai-Shuang Lin
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jia-Nan Gong
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Rui Su
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Ming-Tai Chen
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Li Song
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Chao Shen
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Fang Wang
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yan-Ni Ma
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hua-Lu Zhao
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jia Yu
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Wei-Wei Li
- Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China
| | - Li-Xia Huang
- First Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China; and
| | - Xin-Hua Xu
- Taizhou Cancer Hospital, Zhejiang Province, China
| | - Jun-Wu Zhang
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China;
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9
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Chen Y, Rothnie C, Spring D, Verrier E, Venardos K, Kaye D, Phillips DJ, Hedger MP, Smith JA. Regulation and actions of activin A and follistatin in myocardial ischaemia-reperfusion injury. Cytokine 2014; 69:255-62. [PMID: 25052838 DOI: 10.1016/j.cyto.2014.06.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 04/13/2014] [Accepted: 06/23/2014] [Indexed: 12/14/2022]
Abstract
Activin A, a member of the transforming growth factor-β superfamily, is stimulated early in inflammation via the Toll-like receptor (TLR) 4 signalling pathway, which is also activated in myocardial ischaemia-reperfusion. Neutralising activin A by treatment with the activin-binding protein, follistatin, reduces inflammation and mortality in several disease models. This study assesses the regulation of activin A and follistatin in a murine myocardial ischaemia-reperfusion model and determines whether exogenous follistatin treatment is protective against injury. Myocardial activin A and follistatin protein levels were elevated following 30 min of ischaemia and 2h of reperfusion in wild-type mice. Activin A, but not follistatin, gene expression was also up-regulated. Serum activin A did not change significantly, but serum follistatin decreased. These responses to ischaemia-reperfusion were absent in TLR4(-/-) mice. Pre-treatment with follistatin significantly reduced ischaemia-reperfusion induced myocardial infarction. In mouse neonatal cardiomyocyte cultures, activin A exacerbated, while follistatin reduced, cellular injury after 3h of hypoxia and 2h of re-oxygenation. Neither activin A nor follistatin affected hypoxia-reoxygenation induced reactive oxygen species production by these cells. However, activin A reduced cardiomyocyte mitochondrial membrane potential, and follistatin treatment ameliorated the effect of hypoxia-reoxygenation on cardiomyocyte mitochondrial membrane potential. Taken together, these data indicate that myocardial ischaemia-reperfusion, through activation of TLR4 signalling, stimulates local production of activin A, which damages cardiomyocytes independently of increased reactive oxygen species. Blocking activin action by exogenous follistatin reduces this damage.
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Affiliation(s)
- Yi Chen
- Department of Surgery, Monash Medical Centre, Monash University, Clayton, Victoria 3168, Australia; MIMR-PHI Institute of Medical Research, Monash Medical Centre, Clayton, Victoria 3168, Australia.
| | - Christine Rothnie
- Department of Surgery, School of Medicine, University of Washington, Seattle, WA 98195-6410, USA
| | - Denise Spring
- Department of Surgery, School of Medicine, University of Washington, Seattle, WA 98195-6410, USA
| | - Edward Verrier
- Department of Surgery, School of Medicine, University of Washington, Seattle, WA 98195-6410, USA
| | - Kylie Venardos
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - David Kaye
- Heart Failure Research Group, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria 3004, Australia
| | - David J Phillips
- MIMR-PHI Institute of Medical Research, Monash Medical Centre, Clayton, Victoria 3168, Australia; Epworth Research Institute, Epworth HealthCare, Richmond, Victoria 3121, Australia
| | - Mark P Hedger
- MIMR-PHI Institute of Medical Research, Monash Medical Centre, Clayton, Victoria 3168, Australia
| | - Julian A Smith
- Department of Surgery, Monash Medical Centre, Monash University, Clayton, Victoria 3168, Australia
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10
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Effects of chronic hepatitis C genotype 1 and 4 on serum activins and follistatin in treatment naïve patients and their correlations with interleukin-6, tumour necrosis factor-α, viral load and liver damage. Clin Exp Med 2014; 15:293-302. [DOI: 10.1007/s10238-014-0297-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 05/10/2014] [Indexed: 02/08/2023]
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11
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Thackray VG. Fox tales: regulation of gonadotropin gene expression by forkhead transcription factors. Mol Cell Endocrinol 2014; 385:62-70. [PMID: 24099863 PMCID: PMC3947687 DOI: 10.1016/j.mce.2013.09.034] [Citation(s) in RCA: 23] [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: 06/25/2013] [Revised: 09/25/2013] [Accepted: 09/26/2013] [Indexed: 12/16/2022]
Abstract
Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are produced by pituitary gonadotrope cells and are required for steroidogenesis, the maturation of ovarian follicles, ovulation, and spermatogenesis. Synthesis of LH and FSH is tightly regulated by a complex network of signaling pathways activated by hormones including gonadotropin-releasing hormone, activin and sex steroids. Members of the forkhead box (FOX) transcription factor family have been shown to act as important regulators of development, homeostasis and reproduction. In this review, we focus on the role of four specific FOX factors (FOXD1, FOXL2, FOXO1 and FOXP3) in gonadotropin hormone production and discuss our current understanding of the molecular function of these factors derived from studies in mouse genetic and cell culture models.
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Affiliation(s)
- Varykina G Thackray
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, CA 92093, United States.
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12
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Leddy HA, McNulty AL, Lee SH, Rothfusz NE, Gloss B, Kirby ML, Hutson MR, Cohn DH, Guilak F, Liedtke W. Follistatin in chondrocytes: the link between TRPV4 channelopathies and skeletal malformations. FASEB J 2014; 28:2525-37. [PMID: 24577120 DOI: 10.1096/fj.13-245936] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Point mutations in the calcium-permeable TRPV4 ion channel have been identified as the cause of autosomal-dominant human motor neuropathies, arthropathies, and skeletal malformations of varying severity. The objective of this study was to determine the mechanism by which TRPV4 channelopathy mutations cause skeletal dysplasia. The human TRPV4(V620I) channelopathy mutation was transfected into primary porcine chondrocytes and caused significant (2.6-fold) up-regulation of follistatin (FST) expression levels. Pore altering mutations that prevent calcium influx through the channel prevented significant FST up-regulation (1.1-fold). We generated a mouse model of the TRPV4(V620I) mutation, and found significant skeletal deformities (e.g., shortening of tibiae and digits, similar to the human disease brachyolmia) and increases in Fst/TRPV4 mRNA levels (2.8-fold). FST was significantly up-regulated in primary chondrocytes transfected with 3 different dysplasia-causing TRPV4 mutations (2- to 2.3-fold), but was not affected by an arthropathy mutation (1.1-fold). Furthermore, FST-loaded microbeads decreased bone ossification in developing chick femora (6%) and tibiae (11%). FST gene and protein levels were also increased 4-fold in human chondrocytes from an individual natively expressing the TRPV4(T89I) mutation. Taken together, these data strongly support that up-regulation of FST in chondrocytes by skeletal dysplasia-inducing TRPV4 mutations contributes to disease pathogenesis.
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Affiliation(s)
| | | | | | | | | | | | | | - Daniel H Cohn
- Department of Molecular, Cell, and Developmental Biology and Department of Orthopaedic Surgery, Orthopaedic Hospital Research Center, University of California at Los Angeles, Los Angeles, California, USA
| | | | - Wolfgang Liedtke
- Department of Neurology, Duke University Clinics for Pain and Palliative Care, Duke University Medical Center, Durham, North Carolina, USA; and
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13
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McTavish KJ, Nonis D, Hoang YD, Shimasaki S. Granulosa cell tumor mutant FOXL2C134W suppresses GDF-9 and activin A-induced follistatin transcription in primary granulosa cells. Mol Cell Endocrinol 2013; 372:57-64. [PMID: 23567549 PMCID: PMC3669547 DOI: 10.1016/j.mce.2013.03.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2012] [Revised: 02/27/2013] [Accepted: 03/22/2013] [Indexed: 01/05/2023]
Abstract
A single somatic FOXL2 mutation (FOXL2(C134W)) was identified in almost all granulosa cell tumor (GCT) patients. In the pituitary, FOXL2 and Smad3 coordinately regulate activin stimulation of follistatin transcription. We explored whether a similar regulation occurs in the ovary, and whether FOXL2(C134W) has altered activity. We show that in primary granulosa cells, GDF-9 and activin increase Smad3-mediated follistatin transcription. In contrast to findings in the pituitary, FOXL2 negatively regulates GDF-9 and activin-stimulated follistatin transcription in the ovary. Knockdown of endogenous FOXL2 confirmed this inhibitory role. FOXL2(C134W) displayed enhanced inhibitory activity, completely ablating GDF-9 and activin-induced follistatin transcription. GDF-9 and activin activity was lost when either the smad binding element or the forkhead binding element were mutated, indicating that both sites are required for Smad3 actions. This study highlights that FOXL2 negatively regulates follistatin expression within the ovary, and that the pathogenesis of FOXL2(C134W) may involve an altered interaction with Smad3.
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Affiliation(s)
- Kirsten J McTavish
- Department of Reproductive Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093-0633, USA
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14
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Sakaki-Yumoto M, Liu J, Ramalho-Santos M, Yoshida N, Derynck R. Smad2 is essential for maintenance of the human and mouse primed pluripotent stem cell state. J Biol Chem 2013; 288:18546-60. [PMID: 23649632 DOI: 10.1074/jbc.m112.446591] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Human embryonic stem cells and mouse epiblast stem cells represent a primed pluripotent stem cell state that requires TGF-β/activin signaling. TGF-β and/or activin are commonly thought to regulate transcription through both Smad2 and Smad3. However, the different contributions of these two Smads to primed pluripotency and the downstream events that they may regulate remain poorly understood. We addressed the individual roles of Smad2 and Smad3 in the maintenance of primed pluripotency. We found that Smad2, but not Smad3, is required to maintain the undifferentiated pluripotent state. We defined a Smad2 regulatory circuit in human embryonic stem cells and mouse epiblast stem cells, in which Smad2 acts through binding to regulatory promoter sequences to activate Nanog expression while in parallel repressing autocrine bone morphogenetic protein signaling. Increased autocrine bone morphogenetic protein signaling caused by Smad2 down-regulation leads to cell differentiation toward the trophectoderm, mesoderm, and germ cell lineages. Additionally, induction of Cdx2 expression, as a result of decreased Smad2 expression, leads to repression of Oct4 expression, which, together with the decreased Nanog expression, accelerates the loss of pluripotency. These findings reveal that Smad2 is a unique integrator of transcription and signaling events and is essential for the maintenance of the mouse and human primed pluripotent stem cell state.
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Affiliation(s)
- Masayo Sakaki-Yumoto
- Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Program in Cell Biology, University of California, San Francisco, California 94143, USA
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15
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Hedger MP, de Kretser DM. The activins and their binding protein, follistatin-Diagnostic and therapeutic targets in inflammatory disease and fibrosis. Cytokine Growth Factor Rev 2013; 24:285-95. [PMID: 23541927 DOI: 10.1016/j.cytogfr.2013.03.003] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 03/05/2013] [Indexed: 02/05/2023]
Abstract
The activins, as members of the transforming growth factor-β superfamily, are pleiotrophic regulators of cell development and function, including cells of the myeloid and lymphoid lineages. Clinical and animal studies have shown that activin levels increase in both acute and chronic inflammation, and are frequently indicators of disease severity. Moreover, inhibition of activin action can reduce inflammation, damage, fibrosis and morbidity/mortality in various disease models. Consequently, activin A and, more recently, activin B are emerging as important diagnostic tools and therapeutic targets in inflammatory and fibrotic diseases. Activin antagonists such as follistatin, an endogenous activin-binding protein, offer considerable promise as therapies in conditions as diverse as sepsis, liver fibrosis, acute lung injury, asthma, wound healing and ischaemia-reperfusion injury.
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Affiliation(s)
- M P Hedger
- Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia.
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16
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Hedger MP, Winnall WR. Regulation of activin and inhibin in the adult testis and the evidence for functional roles in spermatogenesis and immunoregulation. Mol Cell Endocrinol 2012; 359:30-42. [PMID: 21964464 DOI: 10.1016/j.mce.2011.09.031] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 09/16/2011] [Accepted: 09/16/2011] [Indexed: 02/03/2023]
Abstract
Activin A provides a unique link between reproduction and immunity, which is especially significant in the adult testis. This cytokine, together with inhibin B and follistatin acting as regulators of activin A activity, is fundamentally involved in the regulation of spermatogenesis and testicular steroidogenesis. However, activin A also has a much broader role in control of inflammation, fibrosis and immunity. In the Sertoli cell, activin A is regulated by signalling pathways that normally regulate stress and inflammation, signalling pathways that intersect with the classical hormonal regulatory pathways mediated by FSH. Modulation of activin A production and activity during spermatogenesis is implicated in the fine control of the cycle of the seminiferous epithelium. The immunoregulatory properties of activin A also suggest that it may be involved in maintaining testicular immune privilege. Consequently, elevated activin A production within the testis during inflammation and infection may contribute to spermatogenic failure, fibrosis and testicular damage.
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Affiliation(s)
- Mark P Hedger
- Monash Institute of Medical Research, Monash University, Melbourne, Victoria, Australia.
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17
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Bilezikjian LM, Justice NJ, Blackler AN, Wiater E, Vale WW. Cell-type specific modulation of pituitary cells by activin, inhibin and follistatin. Mol Cell Endocrinol 2012; 359:43-52. [PMID: 22330643 PMCID: PMC3367026 DOI: 10.1016/j.mce.2012.01.025] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Revised: 01/26/2012] [Accepted: 01/30/2012] [Indexed: 01/01/2023]
Abstract
Activins are multifunctional proteins and members of the TGF-β superfamily. Activins are expressed locally in most tissues and, analogous to the actions of other members of this large family of pleiotropic factors, play prominent roles in the regulation of diverse biological processes in both differentiated and embryonic stem cells. They have an essential role in maintaining tissue homeostasis in the adult and are known to contribute to the developmental programs in the embryo. Activins are further implicated in the growth and metastasis of tumor cells. Through distinct modes of action, inhibins and follistatins function as antagonists of activin and several other TGF-β family members, including a subset of BMPs/GDFs, and modulate cellular responses and the signaling cascades downstream of these ligands. In the pituitary, the activin pathway is known to regulate key aspects of gonadotrope functions and also exert effects on other pituitary cell types. As in other tissues, activin is produced locally by pituitary cells and acts locally by exerting cell-type specific actions on gonadotropes. These local actions of activin on gonadotropes are modulated by the autocrine/paracrine actions of locally secreted follistatin and by the feedback actions of gonadal inhibin. Knowledge about the mechanism of activin, inhibin and follistatin actions is providing information about their importance for pituitary function as well as their contribution to the pathophysiology of pituitary adenomas. The aim of this review is to highlight recent findings and summarize the evidence that supports the important functions of activin, inhibin and follistatin in the pituitary.
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Affiliation(s)
- Louise M Bilezikjian
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
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18
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19
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Gene expression of the lysophosphatidic acid receptor 1 is a target of transforming growth factor beta. Oncogene 2012; 32:3198-206. [PMID: 22824789 PMCID: PMC3480976 DOI: 10.1038/onc.2012.325] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The lysophosphatidic acid (LPA) receptor LPA1/Edg2 is the first identified LPA receptor. Although its wide tissue distribution and biological functions have been well studied, little is known about how LPA1 is transcriptionally regulated. In the current study, we showed that LPA1 is a physiological target of transforming growth factor beta (TGFβ)-mediated repression. In both normal and neoplastic cells, TGFβ inhibits LPA1 promoter activity, LPA1 mRNA expression, and LPA1-dependent chemotaxis and tumor cell invasion. Knockdown of the TGFβ intracellular effector Smad3 or Smad4 with lentivirally transduced shRNA relieved these inhibitory effects of TGFβ. Interestingly, the LPA1 promoter contains two potential TGFβ inhibitory elements (TIEs), each consisting of a Smad binding site and an adjacent E2F4/5 element, structurally similar to the TIE found on the promoter of the well-defined TGFβ target gene c-myc. Deletion and point mutation analyses indicate that the distal TIE located at 401 bp from the transcription initiation site, is required for TGFβ repression of the LPA1 promoter. A DNA pull-down assay showed that the -401 TIE was capable of binding Samd3 and E2F4 in TGFβ-treated cells. TGFβ-induced binding of the Smad complex to the native -401 TIE sequence of the LPA1 gene promoter was further verified by chromatin immunoprecipitation assays. We therefore identified a novel role of TGFβ in the control of LPA1 expression and LPA1-coupled biological functions, adding LPA1 to the list of TGFβ-repressed target genes.
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20
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Wu Y, Zhao J, Zhao W, Pan J, Bauman WA, Cardozo CP. Nandrolone normalizes determinants of muscle mass and fiber type after spinal cord injury. J Neurotrauma 2012; 29:1663-75. [PMID: 22208735 DOI: 10.1089/neu.2011.2203] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Spinal cord injury (SCI) results in atrophy of skeletal muscle and changes from slow oxidative to fast glycolytic fibers, which may reflect reduced levels of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), increased myostatin signaling, or both. In animals, testosterone reduces loss of muscle fiber cross-sectional area and activity of enzymes of energy metabolism. To identify the molecular mechanisms behind the benefits of androgens on paralyzed muscle, male rats were spinal cord transected and treated for 8 weeks with vehicle, testosterone at a physiological replacement dose, or testosterone plus nandrolone, an anabolic steroid. Treatments were initiated immediately after SCI and continued until the day animals were euthanized. In the SCI animals, gastrocnemius muscle mass was significantly increased by testosterone plus nandrolone, but not by testosterone alone. Both treatments significantly reduced nuclear content of Smad2/3 and mRNA levels of activin receptor IIB and follistatin-like 3. Testosterone alone or with nandrolone reversed SCI-induced declines in cellular and nuclear levels of PGC-1α protein and PGC-1α mRNA levels. For PGC-1α target genes, testosterone plus nandrolone partially reversed SCI-induced decreases in levels of proteins without corresponding increases in their mRNA levels. Thus, the findings demonstrate that following SCI, signaling through activin receptors and Smad2/3 is increased, and that androgens suppress activation of this signaling pathway. The findings also indicate that androgens upregulate PGC-1α in paralyzed muscle and promote its nuclear localization, but that these effects are insufficient to fully activate transcription of PGC-1α target genes. Furthermore, the transcription of these genes is not tightly coupled with their translation.
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Affiliation(s)
- Yong Wu
- Center of Excellence for the Medical Consequences of SCI, James J. Peters VA Medical Center, Bronx, NY, USA
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21
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Giesecke K, Hamann H, Sieme H, Distl O. Evaluation of prolactin receptor (PRLR) as candidate gene for male fertility in Hanoverian warmblood horses. Reprod Domest Anim 2011; 45:e124-30. [PMID: 19845882 DOI: 10.1111/j.1439-0531.2009.01533.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Stallion fertility has increasing importance as the artificial insemination is employed in horses more intensely. Molecular genetic markers may be useful tools to evaluate the stallion fertility before breeding. The prolactin receptor gene (PRLR) was chosen as a candidate for stallion fertility because of its influence on testicular and accessory sex gland function. Screening the equine PRLR gene for polymorphisms in Hanoverian stallions revealed two single nucleotide polymorphisms (SNPs). Association and haplotype analyses were performed in 162 Hanoverian warmblood stallions for these intragenic SNPs using the least square means (LSM) of the pregnancy rate per oestrus for stallions and the paternal component and embryonic component of the breeding values (BV) of the pregnancy rate per oestrus. The two SNPs (BIEC2-589441, BIEC2-560860) showed significant associations using single marker and haplotype analysis with the embryonic and paternal component of BV and one SNP (BIEC2-560860) was also significantly associated with the LSM of the pregnancy rate per oestrus. This is the first report on an association of PRLR-associated genetic markers with fertility traits in stallions.
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Affiliation(s)
- K Giesecke
- Institute for Animal Breeding and Genetics, University of Veterinary Medicine Hannover, Hannover, Germany
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22
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Hedger MP, Winnall WR, Phillips DJ, de Kretser DM. The regulation and functions of activin and follistatin in inflammation and immunity. VITAMINS AND HORMONES 2011; 85:255-97. [PMID: 21353885 DOI: 10.1016/b978-0-12-385961-7.00013-5] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The activins are members of the transforming growth factor β superfamily with broad and complex effects on cell growth and differentiation. Activin A has long been known to be a critical regulator of inflammation and immunity, and similar roles are now emerging for activin B, with which it shares 65% sequence homology. These molecules and their binding protein, follistatin, are widely expressed, and their production is increased in many acute and chronic inflammatory conditions. Synthesis and release of the activins are stimulated by inflammatory cytokines, Toll-like receptor ligands, and oxidative stress. The activins interact with heterodimeric serine/threonine kinase receptor complexes to activate SMAD transcription factors and the MAP kinase signaling pathways, which mediate inflammation, stress, and immunity. Follistatin binds to the activins with high affinity, thereby obstructing the activin receptor binding site, and targets them to cell surface proteoglycans and lysosomal degradation. Studies on transgenic mice and those with gene knockouts, together with blocking studies using exogenous follistatin, have established that activin A plays critical roles in the onset of cachexia, acute and chronic inflammatory responses such as septicemia, colitis and asthma, and fibrosis. However, activin A also directs the development of monocyte/macrophages, myeloid dendritic cells, and T cell subsets to promote type 2 and regulatory immune responses. The ability of both endogenous and exogenous follistatin to block the proinflammatory and profibrotic actions of activin A has led to interest in this binding protein as a potential therapeutic for limiting the severity of disease and to improve subsequent damage associated with inflammation and fibrosis. However, the ability of activin A to sculpt the subsequent immune response as well means that the full range of effects that might arise from blocking activin bioactivity will need to be considered in any therapeutic applications.
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Affiliation(s)
- Mark P Hedger
- Monash Institute of Medical Research, Monash University, Monash Medical Centre, Clayton, Victoria, Australia
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23
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Bilezikjian LM, Vale WW. The Local Control of the Pituitary by Activin Signaling and Modulation. OPEN NEUROENDOCRINOLOGY JOURNAL (ONLINE) 2011; 4:90-101. [PMID: 21927629 PMCID: PMC3173763 DOI: 10.2174/1876528901104010090] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The pituitary gland plays a prominent role in the control of many physiological processes. This control is achieved through the actions and interactions of hormones and growth factors that are produced and secreted by the endocrine cell types and the non-endocrine constituents that collectively and functionally define this complex organ. The five endocrine cell types of the anterior lobe of the pituitary, somatotropes, lactotropes, corticotropes, thyrotropes and gonadotropes, are defined by their primary product, growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH), thyroid-stimulating hormone (TSH) and follicle stimulating hormone (FSH)/luteinizing hormone (LH). They are further distinguishable by the presence of cell surface receptors that display high affinity and selectivity for specific hypothalamic hormones and couple to appropriate downstream signaling pathways involved in the control of cell type specific responses, including the release and/or synthesis of pituitary hormones. Central control of the pituitary via the hypothalamus is further fine-tuned by the positive or negative actions of peripheral feedback signals and of a variety of factors that originate from sources within the pituitary. The focus of this review is the latter category of intrinsic factors that exert local control. Special emphasis is given to the TGF-β family of growth factors, in particular activin effects on the gonadotrope population, because a considerable body of evidence supports their contribution to the local modulation of the embryonic and postnatal pituitary as well as pituitary pathogenesis. A number of other substances, including members of the cytokine and FGF families, VEGF, IGF1, PACAP, Ghrelin, adenosine and nitric oxide have also been shown or implicated to function as autocrine/paracrine factors, though, definitive proof remains lacking in some cases. The ever-growing list of putative autocrine/paracrine factors of the pituitary nevertheless has highlighted the complexity of the local network and its impact on pituitary functions.
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Affiliation(s)
- Louise M Bilezikjian
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California, USA
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24
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Dosunmu R, Wu J, Adwan L, Maloney B, Basha MR, McPherson CA, Harry GJ, Rice DC, Zawia NH, Lahiri DK. Lifespan profiles of Alzheimer's disease-associated genes and products in monkeys and mice. J Alzheimers Dis 2010; 18:211-30. [PMID: 19584442 DOI: 10.3233/jad-2009-1138] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease (AD) is characterized by plaques of amyloid-beta (Abeta) peptide, cleaved from amyloid-beta protein precursor (AbetaPP). Our hypothesis is that lifespan profiles of AD-associated mRNA and protein levels in monkeys would differ from mice and that differential lifespan expression profiles would be useful to understand human AD pathogenesis. We compared profiles of AbetaPP mRNA, AbetaPP protein, and Abeta levels in rodents and primates. We also tracked a transcriptional regulator of the AbetaPP gene, specificity protein 1 (SP1), and the beta amyloid precursor cleaving enzyme (BACE1). In mice, AbetaPP and SP1 mRNA and their protein products were elevated late in life; Abeta levels declined in old age. In monkeys, SP1, AbetaPP, and BACE1 mRNA declined in old age, while protein products and Abeta levels rose. Proteolytic processing in both species did not match production of Abeta. In primates, AbetaPP and SP1 mRNA levels coordinate, but an inverse relationship exists with corresponding protein products as well as Abeta levels. Comparison of human DNA and mRNA sequences to monkey and mouse counterparts revealed structural features that may explain differences in transcriptional and translational processing. These findings are important for selecting appropriate models for AD and other age-related diseases.
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Affiliation(s)
- Remi Dosunmu
- Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI, USA
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25
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Kimura F, Sidis Y, Bonomi L, Xia Y, Schneyer A. The follistatin-288 isoform alone is sufficient for survival but not for normal fertility in mice. Endocrinology 2010; 151:1310-9. [PMID: 20032047 PMCID: PMC2840692 DOI: 10.1210/en.2009-1176] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Follistatin (FST) is a natural antagonist of activin and related TGFbeta superfamily ligands that exists as three protein isoforms differing in length at the C terminus. The longest FST315 isoform is found in the circulation, whereas the shortest FST288 isoform is typically found in or on cells and tissues, and the intermediate FST303 isoform is found in gonads. We recently demonstrated that the FST isoforms have distinct biological actions in vitro that, taken together with the differential distribution, suggests they may also have different roles in vivo. To explore the specific role of individual FST isoforms, we created a single-isoform FST288-only mouse. In contrast to the neonatal death of FST global knockout mice, FST288-only mice survive to adulthood. Although they appear normal, FST288-only mice have fertility defects including reduced litter size and frequency. Follicles were counted in ovaries from 8.5- to 400-d-old females. Significantly fewer morphologically healthy antral follicles were found in 100- to 250-d FST288-only ovaries, but there were significantly more secondary, primary, and primordial follicles detected at d 8.5 in FST288-only ovaries. However, depletion of this primordial follicle pool is more rapid in FST288-only females resulting in a deficit by 250 d of age and early cessation of reproduction. Superovulated FST288-only females have fewer ovulated eggs and embryos. These results indicate that the FST isoforms have different activities in vivo, that the FST288-only isoform is sufficient for development, and that loss of FST303 and FST315 isoforms results in fertility defects that resemble activin hyperactivity and premature ovarian failure.
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Affiliation(s)
- Fuminori Kimura
- Pioneer Valley Life Science Institute, 3601 Main Street, Springfield, Massachusetts 01107, USA
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26
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Giesecke K, Hamann H, Stock KF, Woehlke A, Sieme H, Distl O. Evaluation ofSPATA1-associated markers for stallion fertility. Anim Genet 2009; 40:359-65. [DOI: 10.1111/j.1365-2052.2008.01844.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Blount AL, Schmidt K, Justice NJ, Vale WW, Fischer WH, Bilezikjian LM. FoxL2 and Smad3 coordinately regulate follistatin gene transcription. J Biol Chem 2009; 284:7631-45. [PMID: 19106105 PMCID: PMC2658057 DOI: 10.1074/jbc.m806676200] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 12/10/2008] [Indexed: 12/19/2022] Open
Abstract
Follistatin is a transcriptional target and a modulator of activin action. Through an autocrine/paracrine loop, activin controls follistatin levels and thus regulates its own bioavailability. In gonadotropic alphaT3-1 cells, activin induces follistatin transcription primarily through the action of Smad3 at an intronic Smad-binding element (SBE1). Using a proteomics approach, we searched for endogenous alphaT3-1 proteins that participate in SBE1-mediated transcription. We identified FoxL2, a member of the forkhead family, as a candidate modulator of SBE1 function. Mutations of FoxL2 are associated with the blepharophimosis/ptosis/epicanthus inversus syndrome characterized with craniofacial defects and premature ovarian failure. FoxL2 localizes to alpha-glycoprotein subunit- and follicle-stimulating hormone beta-positive cells of the adult mouse pituitary and is present in alphaT3-1 and LbetaT2 cells, but its pituitary actions remain largely unknown. We have determined that FoxL2 binds to a forkhead-binding element (FKHB) located just downstream of the SBE1 site of the follistatin gene and functions as a Smad3 partner to drive SBE1-mediated transcription in alphaT3-1 cells treated with activin. Chromatin immunoprecipitation assays confirm that endogenous FoxL2 and Smad3 are recruited to the intronic enhancer of the follistatin gene where the SBE1 and FKHB sites are located. Exogenous FoxL2 enhances SBE1-mediated transcription, and short hairpin RNA-mediated knockdown of endogenous FoxL2 protein compromises this effect in alphaT3-1 cells. FoxL2 directly associates with Smad3 but not Smad2 or Smad4. This association between Smad3 and FoxL2 is mediated by the MH2 domain of Smad3 and is dependent on an intact forkhead domain in FoxL2. Altogether, these observations highlight a novel role for FoxL2 and suggest that it may function as a transcriptional regulator and a coordinator of Smad3 targets.
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Affiliation(s)
- Amy L Blount
- Clayton Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037, USA
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