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Abstract
Understanding the molecular mechanisms underlying pituitary organogenesis and function is essential for improving therapeutics and molecular diagnoses for hypopituitarism. We previously found that deletion of the forkhead factor, Foxo1, in the pituitary gland early in development delays somatotrope differentiation. While these mice grow normally, they have reduced growth hormone expression and free serum insulin-like growth factor-1 (IGF1) levels, suggesting a defect in somatotrope function. FOXO factors show functional redundancy in other tissues, so we deleted both Foxo1 and its closely related family member, Foxo3, from the primordial pituitary. We find that this results in a significant reduction in growth. Consistent with this, male and female mice in which both genes have been deleted in the pituitary gland (dKO) exhibit reduced pituitary growth hormone expression and serum IGF1 levels. Expression of the somatotrope differentiation factor, Neurod4, is reduced in these mice. This suggests a mechanism underlying proper somatotrope function is the regulation of Neurod4 expression by FOXO factors. Additionally, dKO mice have reduced Lhb expression and females also have reduced Fshb and Prl expression. These studies reveal FOXO transcription factors as important regulators of pituitary gland function.
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Affiliation(s)
- Caitlin E Stallings
- Department of Physiology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Jyoti Kapali
- Department of Physiology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Brian W Evans
- Department of Physiology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Stacey R McGee
- Department of Physiology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Buffy S Ellsworth
- Department of Physiology, Southern Illinois University, Carbondale, IL 62901, USA
- Correspondence: Buffy S. Ellsworth, Ph.D., Department of Physiology, Southern Illinois University, 1135 Lincoln Drive, Life Science III room 2062, Carbondale, IL 62901, USA.
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Beaulac HJ, Gilels F, Zhang J, Jeoung S, White PM. Primed to die: an investigation of the genetic mechanisms underlying noise-induced hearing loss and cochlear damage in homozygous Foxo3-knockout mice. Cell Death Dis 2021; 12:682. [PMID: 34234110 PMCID: PMC8263610 DOI: 10.1038/s41419-021-03972-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 02/06/2023]
Abstract
The prevalence of noise-induced hearing loss (NIHL) continues to increase, with limited therapies available for individuals with cochlear damage. We have previously established that the transcription factor FOXO3 is necessary to preserve outer hair cells (OHCs) and hearing thresholds up to two weeks following mild noise exposure in mice. The mechanisms by which FOXO3 preserves cochlear cells and function are unknown. In this study, we analyzed the immediate effects of mild noise exposure on wild-type, Foxo3 heterozygous (Foxo3+/-), and Foxo3 knock-out (Foxo3-/-) mice to better understand FOXO3's role(s) in the mammalian cochlea. We used confocal and multiphoton microscopy to examine well-characterized components of noise-induced damage including calcium regulators, oxidative stress, necrosis, and caspase-dependent and caspase-independent apoptosis. Lower immunoreactivity of the calcium buffer Oncomodulin in Foxo3-/- OHCs correlated with cell loss beginning 4 h post-noise exposure. Using immunohistochemistry, we identified parthanatos as the cell death pathway for OHCs. Oxidative stress response pathways were not significantly altered in FOXO3's absence. We used RNA sequencing to identify and RT-qPCR to confirm differentially expressed genes. We further investigated a gene downregulated in the unexposed Foxo3-/- mice that may contribute to OHC noise susceptibility. Glycerophosphodiester phosphodiesterase domain containing 3 (GDPD3), a possible endogenous source of lysophosphatidic acid (LPA), has not previously been described in the cochlea. As LPA reduces OHC loss after severe noise exposure, we treated noise-exposed Foxo3-/- mice with exogenous LPA. LPA treatment delayed immediate damage to OHCs but was insufficient to ultimately prevent their death or prevent hearing loss. These results suggest that FOXO3 acts prior to acoustic insult to maintain cochlear resilience, possibly through sustaining endogenous LPA levels.
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MESH Headings
- Animals
- Cell Death
- Disease Models, Animal
- Female
- Forkhead Box Protein O3/deficiency
- Forkhead Box Protein O3/genetics
- Gene Expression Regulation
- Hair Cells, Auditory, Outer/drug effects
- Hair Cells, Auditory, Outer/metabolism
- Hair Cells, Auditory, Outer/pathology
- Hearing
- Hearing Loss, Noise-Induced/drug therapy
- Hearing Loss, Noise-Induced/genetics
- Hearing Loss, Noise-Induced/metabolism
- Hearing Loss, Noise-Induced/pathology
- Homozygote
- Lysophospholipids/metabolism
- Lysophospholipids/pharmacology
- Male
- Mice, Knockout
- Noise
- Phosphoric Diester Hydrolases/genetics
- Phosphoric Diester Hydrolases/metabolism
- Time Factors
- Mice
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Affiliation(s)
- Holly J Beaulac
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
- The Jackson Laboratory, Bar Harbor, ME, USA
| | - Felicia Gilels
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
- Department of Pathology, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Jingyuan Zhang
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
- Department of Otolaryngology, Otolaryngology-Head and Neck Surgery, Harvard Medical School, Boston Children's Hospital Center for Life Science, Boston, MA, USA
| | - Sarah Jeoung
- University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
| | - Patricia M White
- Department of Neuroscience, Ernest J. Del Monte Institute for Neuroscience, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA.
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3
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Luo M, Wu C, Guo E, Peng S, Zhang L, Sun W, Liu D, Hu G, Hu G. FOXO3a knockdown promotes radioresistance in nasopharyngeal carcinoma by inducing epithelial-mesenchymal transition and the Wnt/β-catenin signaling pathway. Cancer Lett 2019; 455:26-35. [PMID: 31022422 DOI: 10.1016/j.canlet.2019.04.019] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Revised: 04/11/2019] [Accepted: 04/15/2019] [Indexed: 12/19/2022]
Abstract
Mutations in the forkhead box O 3a (FOXO3a) gene are closely related to the progression of several types of cancers. However, few studies explore the relationship between FOXO3a and nasopharyngeal carcinoma (NPC). Our findings demonstrate that silencing FOXO3a promotes tumor radioresistance of NPC in vitro and in vivo through inducing EMT and activating Wnt/β-catenin signal pathway. These data establish that FOXO3a can be a novel and reliable NPC marker and a potential therapeutic target against NPC.
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Affiliation(s)
- Min Luo
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Cheng Wu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China
| | - Ergang Guo
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China
| | - Shan Peng
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Linli Zhang
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China
| | - Wei Sun
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China
| | - Dongbo Liu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China
| | - Guangyuan Hu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China.
| | - Guoqing Hu
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, Wuhan, People's Republic of China.
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Alvarez‐Garcia O, Matsuzaki T, Olmer M, Miyata K, Mokuda S, Sakai D, Masuda K, Asahara H, Lotz MK. FOXO are required for intervertebral disk homeostasis during aging and their deficiency promotes disk degeneration. Aging Cell 2018; 17:e12800. [PMID: 29963746 PMCID: PMC6156454 DOI: 10.1111/acel.12800] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/21/2018] [Accepted: 05/27/2018] [Indexed: 12/19/2022] Open
Abstract
Intervertebral disk (IVD) degeneration is a prevalent age-associated musculoskeletal disorder and a major cause of chronic low back pain. Aging is the main risk factor for the disease, but the molecular mechanisms regulating IVD homeostasis during aging are unknown. The aim of this study was to investigate the function of FOXO, a family of transcription factors linked to aging and longevity, in IVD aging and age-related degeneration. Conditional deletion of all FOXO isoforms (FOXO1, 3, and 4) in IVD using the Col2a1Cre and AcanCreER mouse resulted in spontaneous development of IVD degeneration that was driven by severe cell loss in the nucleus pulposus (NP) and cartilaginous endplates (EP). Conditional deletion of individual FOXO in mature mice showed that FOXO1 and FOXO3 are the dominant isoforms and have redundant functions in promoting IVD homeostasis. Gene expression analyses indicated impaired autophagy and reduced antioxidant defenses in the NP of FOXO-deficient IVD. In primary human NP cells, FOXO directly regulated autophagy and adaptation to hypoxia and promoted resistance to oxidative and inflammatory stress. Our findings demonstrate that FOXO are critical regulators of IVD homeostasis during aging and suggest that maintaining or restoring FOXO expression can be a therapeutic strategy to promote healthy IVD aging and delay the onset of IVD degeneration.
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Affiliation(s)
- Oscar Alvarez‐Garcia
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
| | - Tokio Matsuzaki
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
| | - Merissa Olmer
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
| | - Kohei Miyata
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
| | - Sho Mokuda
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
| | - Daisuke Sakai
- Department of Orthopedic SurgeryTokai University School of MedicineIsehara‐shiJapan
| | - Koichi Masuda
- Department of Orthopedic SurgeryUniversity of California‐San Diego, Altman Clinical Translational Research InstituteLa JollaCalifornia
| | - Hiroshi Asahara
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
| | - Martin K. Lotz
- Department of Molecular MedicineThe Scripps Research InstituteLa JollaCalifornia
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Eelen G, Verlinden L, Maes C, Beullens I, Gysemans C, Paik JH, DePinho RA, Bouillon R, Carmeliet G, Verstuyf A. Forkhead box O transcription factors in chondrocytes regulate endochondral bone formation. J Steroid Biochem Mol Biol 2016; 164:337-343. [PMID: 26232637 DOI: 10.1016/j.jsbmb.2015.07.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 07/26/2015] [Indexed: 01/14/2023]
Abstract
The differentiation of embryonic mesenchymal cells into chondrocytes and the subsequent formation of a cartilaginous scaffold that enables the formation of long bones are hallmarks of endochondral ossification. During this process, chondrocytes undergo a remarkable sequence of events involving proliferation, differentiation, hypertrophy and eventually apoptosis. Forkhead Box O (FoxO) transcription factors (TFs) are well-known regulators of such cellular processes. Although FoxO3a was previously shown to be regulated by 1,25-dihydroxyvitamin D3 in osteoblasts, a possible role for this family of TFs in chondrocytes during endochondral ossification remains largely unstudied. By crossing Collagen2-Cre mice with FoxO1lox/lox;FoxO3alox/lox;FoxO4lox/lox mice, we generated mice in which the three main FoxO isoforms were deleted in growth plate chondrocytes (chondrocyte triple knock-out; CTKO). Intriguingly, CTKO neonates showed a distinct elongation of the hypertrophic zone of the growth plate. CTKO mice had increased overall body and tail length at eight weeks of age and suffered from severe skeletal deformities at older ages. CTKO chondrocytes displayed decreased expression of genes involved in redox homeostasis. These observations illustrate the importance of FoxO signaling in chondrocytes during endochondral ossification.
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Affiliation(s)
- G Eelen
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - L Verlinden
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - C Maes
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - I Beullens
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - C Gysemans
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - J-H Paik
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York City, NY, USA
| | - R A DePinho
- Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - R Bouillon
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - G Carmeliet
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium
| | - A Verstuyf
- Clinical and Experimental Endocrinology, KU Leuven, B-3000 Leuven, Belgium.
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