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Rutkoski R, Debarba LK, Stilgenbauer L, Rosenthal T, Sadagurski M, Nagorny P. Selective (α)-l-Rhamnosylation and Neuroprotective Activity Exploration of Cardiotonic Steroids. ACS Med Chem Lett 2024; 15:280-286. [PMID: 38352829 PMCID: PMC10860192 DOI: 10.1021/acsmedchemlett.3c00517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/27/2023] [Accepted: 01/02/2024] [Indexed: 02/16/2024] Open
Abstract
This work describes the studies on the direct C3-glycosylation of the C19-hydroxylated cardiotonic steroids strophanthidol, anhydro-ouabagenin, and ouabagenin using a strategy based on in situ protection of the C5 and C19 hydroxyl groups with boronic acids. While this strategy resulted in a successful one-pot C3-selective glycosylation of strophanthidol and anhydro-ouabegenin, it failed to provide ouabain from ouabagenin. The neuroprotective activity of the synthetic and natural glycosides against LPS-induced neuroinflammation was explored in neonatal mouse primary glia cells. Co-administration of natural and synthetic C3-glycosides at 200 nM concentrations resulted in the significant reduction of the LPS-induced neuroinflammatory markers IL-6, IL-1, TNFα, and IKBKE, with the anhydro-ouabagenin-3-(α)-l-rhamnoside (anhydro-ouabain) showing the most significant effect. At the same time, unglycosylated anhydro-ouabagenin enhanced rather than suppressed LPS-induced neuroinflammation.
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Affiliation(s)
- Ryan Rutkoski
- Department
of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Lucas Kniess Debarba
- Department
of Biological Sciences, Institute of Environmental Health Sciences,
Integrative Biosciences Center, Wayne State
University, Detroit, Michigan 48202, United States
| | - Lukas Stilgenbauer
- Department
of Biological Sciences, Institute of Environmental Health Sciences,
Integrative Biosciences Center, Wayne State
University, Detroit, Michigan 48202, United States
| | - Tay Rosenthal
- Small
Molecule Discovery & Development, Corteva Agriscience, 9330 Zionsville Road, Indianapolis, Indiana 46268, United States
| | - Marianna Sadagurski
- Department
of Biological Sciences, Institute of Environmental Health Sciences,
Integrative Biosciences Center, Wayne State
University, Detroit, Michigan 48202, United States
| | - Pavel Nagorny
- Department
of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States
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2
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Ding J, Song Y, Liu C, Sadagurski M. Editorial: Environmental toxicity in reproduction. Front Physiol 2023; 14:1351594. [PMID: 38173932 PMCID: PMC10763237 DOI: 10.3389/fphys.2023.1351594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Affiliation(s)
- Jiahui Ding
- CS Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, United States
| | - Yong Song
- Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, Grand Rapids, MI, United States
| | - Chunyan Liu
- Tongji Medical College, Institute of Reproductive Health, Huazhong University of Science and Technology, Wuhan, China
| | - Marianna Sadagurski
- Integrative Biosciences Center (IBio), Department of Biological Sciences, Wayne State University, Detroit, MI, United States
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3
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Debarba LK, Jayarathne HSM, Stilgenbauer L, Terra Dos Santos AL, Koshko L, Scofield S, Sullivan R, Mandal A, Klueh U, Sadagurski M. Microglial NF-κB Signaling Deficiency Protects Against Metabolic Disruptions Caused by Volatile Organic Compound via Modulating the Hypothalamic Transcriptome. bioRxiv 2023:2023.11.08.566279. [PMID: 38014216 PMCID: PMC10680567 DOI: 10.1101/2023.11.08.566279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Prolonged exposure to benzene, a prevalent volatile organic compound (VOC), at concentrations found in smoke, triggers hyperglycemia, and inflammation in mice. Corroborating this with existing epidemiological data, we show a strong correlation between environmental benzene exposure and metabolic impairments in humans. To uncover the underlying mechanisms, we employed a controlled exposure system and continuous glucose monitoring (CGM), revealing rapid blood glucose surges and disturbances in energy homeostasis in mice. These effects were attributed to alterations in the hypothalamic transcriptome, specifically impacting insulin and immune response genes, leading to hypothalamic insulin resistance and neuroinflammation. Moreover, benzene exposure activated microglial transcription characterized by heightened expression of IKKβ/NF-κB-related genes. Remarkably, selective removal of IKKβ in immune cells or adult microglia in mice alleviated benzene-induced hypothalamic gliosis, and protected against hyperglycemia. In summary, our study uncovers a crucial pathophysiological mechanism, establishing a clear link between airborne toxicant exposure and the onset of metabolic diseases.
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Zhang K, Liu C, Sadagurski M, Sun Q. Editorial: Environmental stressors and metabolic disease. Front Endocrinol (Lausanne) 2023; 14:1298687. [PMID: 37867520 PMCID: PMC10588619 DOI: 10.3389/fendo.2023.1298687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 09/27/2023] [Indexed: 10/24/2023] Open
Affiliation(s)
- Kezhong Zhang
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Biochemistry, Microbiology, and Immunology, Wayne State University School of Medicine, Detroit, MI, United States
| | - Cuiqing Liu
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
| | - Marianna Sadagurski
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, United States
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, MI, United States
| | - Qinghua Sun
- School of Public Health, Zhejiang Chinese Medical University, Hangzhou, China
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5
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Kesserwan S, Sadagurski M, Mao L, Klueh U. Mast Cell Deficiency in Mice Attenuates Insulin Phenolic Preservative-Induced Inflammation. Biomedicines 2023; 11:2258. [PMID: 37626754 PMCID: PMC10452641 DOI: 10.3390/biomedicines11082258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/04/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
One major obstacle that limits the lifespan of insulin infusion pumps is surmounting the tissue site reaction at the device implantation site. All commercial insulin formulations contain insulin phenolic preservatives (IPPs) designed to ensure insulin protein stability and prolong shelf-life. However, our laboratory demonstrated that these preservatives are cytotoxic and induce inflammation. Mature mast cells (MCs) reside in cutaneous tissue and are one of the first responders to an epidermal breach. Upon activation, MCs release proinflammatory and immunomodulatory prepacked mediators that exacerbate these inflammatory reactions. Thus, we hypothesized that once the epidermis is breached, cutaneous MCs are triggered inciting the inflammatory response to IPP-induced inflammation. This hypothesis was pursued utilizing our modified in vivo mouse air pouch model, including a c-kit dependent (C57BL/6J-kitW-sh/W-sh) and a c-kit independent (Cpa3-Cre; Mcl-1fl/fl) MC-deficient mouse model. Leukocytes were quantified in the mouse air pouch lavage fluid following flow cytometry analysis for IPP infusion under three different states, insulin-containing phenolic preservatives (Humalog®), insulin preservatives alone, and normal saline as a control. The air pouch wall was assessed using histopathological evaluations. Flow cytometry analysis demonstrated a statistically significant difference in inflammatory cell recruitment for both MC-deficient mouse models when compared to the control strain including infused control saline. Significantly less inflammation was observed at the site of infusion for the MC-deficient strains compared to the control strain. Overall, concordant results were obtained in both mouse types, C57Bl6-kitW-sh/W-sh and Cpa3-Cre; Mcl-1fl/fl. These findings in multiple model systems support the conclusion that MCs have important or possible unique roles in IPP-induced inflammation.
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Affiliation(s)
| | | | | | - Ulrike Klueh
- Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI 48202, USA; (S.K.); (M.S.)
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Maxwell A, Adzibolosu N, Hu A, You Y, Stemmer PM, Ruden DM, Petriello MC, Sadagurski M, Debarba LK, Koshko L, Ramadoss J, Nguyen AT, Richards D, Liao A, Mor G, Ding J. Intrinsic sexual dimorphism in the placenta determines the differential response to benzene exposure. iScience 2023; 26:106287. [PMID: 37153445 PMCID: PMC10156617 DOI: 10.1016/j.isci.2023.106287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/09/2022] [Accepted: 02/22/2023] [Indexed: 03/02/2023] Open
Abstract
Maternal immune activation (MIA) by environmental challenges is linked to severe developmental complications, such as neurocognitive disorders, autism, and even fetal/maternal death. Benzene is a major toxic compound in air pollution that affects the mother as well as the fetus and has been associated with reproductive complications. Our objective was to elucidate whether benzene exposure during gestation triggers MIA and its impact on fetal development. We report that benzene exposure during pregnancy leads MIA associated with increased fetal resorptions, fetal growth, and abnormal placenta development. Furthermore, we demonstrate the existence of a sexual dimorphic response to benzene exposure in male and female placentas. The sexual dimorphic response is a consequence of inherent differences between male and female placenta. These data provide crucial information on the origins or sexual dimorphism and how exposure to environmental factors can have a differential impact on the development of male and female offspring.
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Affiliation(s)
- Anthony Maxwell
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | - Nicholas Adzibolosu
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | - Anna Hu
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | - Yuan You
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | - Paul M. Stemmer
- Institute of Environmental Health Sciences, Wayne State University, Detroit, MI, USA
| | - Douglas M. Ruden
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | - Michael C. Petriello
- Institute of Environmental Health Sciences and Department of Pharmacology, Wayne State University, Detroit, MI, USA
| | - Marianna Sadagurski
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, MI, USA
| | - Lucas K. Debarba
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, MI, USA
| | - Lisa Koshko
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, MI, USA
| | - Jayanth Ramadoss
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | | | - Darby Richards
- School of Medicine, Wayne State University, Detroit, MI, USA
| | - Aihua Liao
- Institute of Reproductive Health, Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, PR China
| | - Gil Mor
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
| | - Jiahui Ding
- C.S Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology, Wayne State University, Detroit, MI, USA
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Koshko L, Scofield S, Debarba L, Stilgenbauer L, Fakhoury P, Jayarathne H, Perez-Mojica JE, Griggs E, Lempradl A, Sadagurski M. Prenatal benzene exposure in mice alters offspring hypothalamic development predisposing to metabolic disease in later life. Chemosphere 2023; 330:138738. [PMID: 37084897 DOI: 10.1016/j.chemosphere.2023.138738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/10/2023] [Accepted: 04/18/2023] [Indexed: 05/03/2023]
Abstract
Maternal exposure to environmental contaminants during pregnancy poses a significant threat to a developing fetus, as these substances can easily cross the placenta and disrupt the neurodevelopment of offspring. Specifically, the hypothalamus is essential in the regulation of metabolism, notably during critical windows of development. An abnormal hormonal and inflammatory milieu during development can trigger persistent changes in the function of hypothalamic circuits, leading to long-lasting effects on the body's energy homeostasis and metabolism. We recently demonstrated that gestational exposure to clinically relevant levels of benzene induces severe metabolic dysregulation in the offspring. Given the central role of the hypothalamus in metabolic control, we hypothesized that prenatal exposure to benzene impacts hypothalamic development, contributing to the adverse metabolic effects in the offspring. C57BL/6JB dams were exposed to benzene at 50 ppm in the inhalation chambers exclusively during pregnancy (from E0.5 to E19). Transcriptomic analysis of the exposed offspring at postnatal day 21 (P21) revealed hypothalamic changes in genes related to metabolic regulation, inflammation, and neurodevelopment exclusively in males. Moreover, the hypothalamus of prenatally benzene-exposed male offspring displayed alterations in orexigenic and anorexigenic projections, impairments in leptin signaling, and increased microgliosis. Additional exposure to benzene during lactation did not promote further microgliosis or astrogliosis in the offspring, while the high-fat diet (HFD) challenge in adulthood exacerbated glucose metabolism and hypothalamic inflammation in benzene-exposed offspring of both sexes. These findings reveal the persistent adverse effects of prenatal benzene exposure on hypothalamic circuits and neuroinflammation, predisposing the offspring to long-lasting metabolic health conditions.
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Affiliation(s)
- Lisa Koshko
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA
| | - Sydney Scofield
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA
| | - Lucas Debarba
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA
| | - Lukas Stilgenbauer
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA
| | - Patrick Fakhoury
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA
| | - Hashan Jayarathne
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA
| | | | - Ellen Griggs
- Van Andel Research Institute, Grand Rapids, MI, USA
| | | | - Marianna Sadagurski
- Department of Biological Sciences, Institute of Environmental Health Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, MI, USA.
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8
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Jayarathne H, Liu W, Sadagurski M. Repurposing Canagliflozin to target brain aging. Aging (Albany NY) 2023; 15:2367-2368. [PMID: 36971696 PMCID: PMC10120889 DOI: 10.18632/aging.204624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 02/24/2023] [Indexed: 04/22/2023]
Affiliation(s)
- Hashan Jayarathne
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, MI 48202, USA
| | - Wanqing Liu
- Department of Pharmaceutical Science, IBio (Integrative Biosciences Center), Wayne State University, Detroit, MI 48202, USA
| | - Marianna Sadagurski
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, MI 48202, USA
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9
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Adelabu I, Chowdhury MRH, Nantogma S, Oladun C, Ahmed F, Stilgenbauer L, Sadagurski M, Theis T, Goodson BM, Chekmenev EY. Efficient SABRE-SHEATH Hyperpolarization of Potent Branched-Chain-Amino-Acid Metabolic Probe [1- 13C]ketoisocaproate. Metabolites 2023; 13:200. [PMID: 36837820 PMCID: PMC9963635 DOI: 10.3390/metabo13020200] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/22/2023] [Accepted: 01/23/2023] [Indexed: 02/03/2023] Open
Abstract
Efficient 13C hyperpolarization of ketoisocaproate is demonstrated in natural isotopic abundance and [1-13C]enriched forms via SABRE-SHEATH (Signal Amplification By Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei). Parahydrogen, as the source of nuclear spin order, and ketoisocaproate undergo simultaneous chemical exchange with an Ir-IMes-based hexacoordinate complex in CD3OD. SABRE-SHEATH enables spontaneous polarization transfer from parahydrogen-derived hydrides to the 13C nucleus of transiently bound ketoisocaproate. 13C polarization values of up to 18% are achieved at the 1-13C site in 1 min in the liquid state at 30 mM substrate concentration. The efficient polarization build-up becomes possible due to favorable relaxation dynamics. Specifically, the exponential build-up time constant (14.3 ± 0.6 s) is substantially lower than the corresponding polarization decay time constant (22.8 ± 1.2 s) at the optimum polarization transfer field (0.4 microtesla) and temperature (10 °C). The experiments with natural abundance ketoisocaproate revealed polarization level on the 13C-2 site of less than 1%-i.e., one order of magnitude lower than that of the 1-13C site-which is only partially due to more-efficient relaxation dynamics in sub-microtesla fields. We rationalize the overall much lower 13C-2 polarization efficiency in part by less favorable catalyst-binding dynamics of the C-2 site. Pilot SABRE experiments at pH 4.0 (acidified sample) versus pH 6.1 (unaltered sodium [1-13C]ketoisocaproate) reveal substantial modulation of SABRE-SHEATH processes by pH, warranting future systematic pH titration studies of ketoisocaproate, as well as other structurally similar ketocarboxylate motifs including pyruvate and alpha-ketoglutarate, with the overarching goal of maximizing 13C polarization levels in these potent molecular probes. Finally, we also report on the pilot post-mortem use of HP [1-13C]ketoisocaproate in a euthanized mouse, demonstrating that SABRE-hyperpolarized 13C contrast agents hold promise for future metabolic studies.
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Affiliation(s)
- Isaiah Adelabu
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Md Raduanul H. Chowdhury
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Shiraz Nantogma
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Clementinah Oladun
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Firoz Ahmed
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Lukas Stilgenbauer
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Marianna Sadagurski
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
| | - Thomas Theis
- Department of Chemistry, Department of Physics, Joint UNC-CH & NC State Department of Biomedical Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Boyd M. Goodson
- School of Chemical & Biomolecular Sciences and Materials Technology Center, Southern Illinois University, Carbondale, IL 62901, USA
| | - Eduard Y. Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, MI 48202, USA
- Russian Academy of Sciences, Leninskiy Prospekt 14, 119991 Moscow, Russia
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10
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Koshko L, Scofield S, Debarba L, Stilgenbauer L, Sacla M, Fakhoury P, Jayarathne H, Perez-Mojica JE, Griggs E, Lempradl A, Sadagurski M. Prenatal benzene exposure alters offspring hypothalamic development predisposing to metabolic disease in later life. bioRxiv 2023:2023.01.05.522910. [PMID: 36711607 PMCID: PMC9881982 DOI: 10.1101/2023.01.05.522910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The hypothalamus is essential in the regulation of metabolism, notably during critical windows of development. An abnormal hormonal and inflammatory milieu during development can trigger persistent changes in the function of hypothalamic circuits, leading to long-lasting effects on the body’s energy homeostasis and metabolism. We recently demonstrated that gestational exposure to benzene at smoking levels induces severe metabolic dysregulation in the offspring. Given the central role of the hypothalamus in metabolic control, we hypothesized that prenatal exposure to benzene impacts hypothalamic development, contributing to the adverse metabolic effects in the offspring. C57BL/6JB dams were exposed to benzene in the inhalation chambers exclusively during pregnancy (from E0.5 to E19). The transcriptome analysis of the offspring hypothalamus at postnatal day 21 (P21) revealed changes in genes related to metabolic regulation, inflammation, and neurodevelopment exclusively in benzene-exposed male offspring. Moreover, the hypothalamus of prenatally benzene-exposed male offspring displayed alterations in orexigenic and anorexigenic projections, impairments in leptin signaling, and increased microgliosis. Additional exposure to benzene during lactation did not promote further microgliosis or astrogliosis in the offspring, while the high-fat diet (HFD) challenge in adulthood exacerbated glucose metabolism and hypothalamic inflammation in benzene-exposed offspring of both sexes. These findings reveal the persistent impact of prenatal benzene exposure on hypothalamic circuits and neuroinflammation, predisposing the offspring to long-lasting metabolic health conditions.
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11
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Jayarathne HSM, Debarba LK, Jaboro JJ, Ginsburg BC, Miller RA, Sadagurski M. Neuroprotective effects of Canagliflozin: Lessons from aged genetically diverse UM-HET3 mice. Aging Cell 2022; 21:e13653. [PMID: 35707855 PMCID: PMC9282842 DOI: 10.1111/acel.13653] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 05/13/2022] [Accepted: 05/25/2022] [Indexed: 01/24/2023] Open
Abstract
The aging brain is characterized by progressive increases in neuroinflammation and central insulin resistance, which contribute to neurodegenerative diseases and cognitive impairment. Recently, the Interventions Testing Program demonstrated that the anti-diabetes drug, Canagliflozin (Cana), a sodium-glucose transporter 2 inhibitor, led to lower fasting glucose and improved glucose tolerance in both sexes, but extended median lifespan by 14% in male mice only. Here, we show that Cana treatment significantly improved central insulin sensitivity in the hypothalamus and the hippocampus of 30-month-old male mice. Aged males produce more robust neuroimmune responses than aged females. Remarkably, Cana-treated male and female mice showed significant reductions in age-associated hypothalamic gliosis with a decrease in inflammatory cytokine production by microglia. However, in the hippocampus, Cana reduced microgliosis and astrogliosis in males, but not in female mice. The decrease in microgliosis was partially correlated with reduced phosphorylation of S6 kinase in microglia of Cana-treated aged male, but not female mice. Thus, Cana treatment improved insulin responsiveness in aged male mice. Furthermore, Cana treatment improved exploratory and locomotor activity of 30-month-old male but not female mice. Taken together, we demonstrate the sex-specific neuroprotective effects of Cana treatment, suggesting its application for the potential treatment of neurodegenerative diseases.
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Affiliation(s)
- Hashan S M Jayarathne
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, USA
| | - Lucas K Debarba
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, USA
| | - Jacob J Jaboro
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, USA
| | - Brett C Ginsburg
- Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center, San Antonio, Texas, USA
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Marianna Sadagurski
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, USA
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12
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Koshko L, Scofield S, Mor G, Sadagurski M. Prenatal Pollutant Exposures and Hypothalamic Development: Early Life Disruption of Metabolic Programming. Front Endocrinol (Lausanne) 2022; 13:938094. [PMID: 35909533 PMCID: PMC9327615 DOI: 10.3389/fendo.2022.938094] [Citation(s) in RCA: 0] [Impact Index Per Article: 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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 06/13/2022] [Indexed: 11/23/2022] Open
Abstract
Environmental contaminants in ambient air pollution pose a serious risk to long-term metabolic health. Strong evidence shows that prenatal exposure to pollutants can significantly increase the risk of Type II Diabetes (T2DM) in children and all ethnicities, even without the prevalence of obesity. The central nervous system (CNS) is critical in regulating whole-body metabolism. Within the CNS, the hypothalamus lies at the intersection of the neuroendocrine and autonomic systems and is primarily responsible for the regulation of energy homeostasis and satiety signals. The hypothalamus is particularly sensitive to insults during early neurodevelopmental periods and may be susceptible to alterations in the formation of neural metabolic circuitry. Although the precise molecular mechanism is not yet defined, alterations in hypothalamic developmental circuits may represent a leading cause of impaired metabolic programming. In this review, we present the current knowledge on the links between prenatal pollutant exposure and the hypothalamic programming of metabolism.
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Affiliation(s)
- Lisa Koshko
- Integrative Biosciences Center, Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - Sydney Scofield
- Integrative Biosciences Center, Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - Gil Mor
- C.S. Mott Center for Human Growth and Development, Department of Obstetrics and Gynecology School of Medicine, Wayne State University, Detroit, MI, United States
| | - Marianna Sadagurski
- Integrative Biosciences Center, Department of Biological Sciences, Wayne State University, Detroit, MI, United States
- *Correspondence: Marianna Sadagurski,
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Debarba LK, Jayarathne HSM, Miller RA, Garratt M, Sadagurski M. 17-a-estradiol has sex-specific effects on neuroinflammation that are partly reversed by gonadectomy. J Gerontol A Biol Sci Med Sci 2021; 77:66-74. [PMID: 34309657 DOI: 10.1093/gerona/glab216] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Indexed: 11/13/2022] Open
Abstract
17-α-estradiol (17aE2) treatment from 4-months of age extends lifespan in male mice and can reduce neuroinflammatory responses in the hypothalamus of 12-month-old males. Although 17aE2 improves longevity in males, female mice are unaffected, suggesting a sexually dimorphic pattern of lifespan regulation. We tested whether the sex-specific effects of 17aE2 on neuroinflammatory responses are affected by gonadal removal and whether hypothalamic changes extend to other brain regions in old age. We show that sex-specific effects of 17aE2 on age-associated gliosis are brain region-specific and are partially dependent on gonadectomy. 17aE2 treatment started at 4 months of age protected 25-month-old males from hypothalamic inflammation. Castration before 17aE2 exposure reduced the effect of 17aE2 on hypothalamic astrogliosis in males. By contrast, sex-specific inhibition of microgliosis generated by 17aE2 was not significantly affected by castration. In the hippocampus, gonadectomy influenced the severity of gliosis and the responsiveness to 17aE2 in a region-dependent manner. The male-specific effects of 17aE2 correlate with increases in hypothalamic ERα expression, specifically in gonadally intact males, consistent with the idea that 17aE2 might act through this receptor. Our results indicate that neuroinflammatory responses to 17aE2 are partially controlled by the presence of sex-specific gonads. Loss of gonadal function and age-associated neuroinflammation could, therefore, influence late-life health and disease onset, leading to sexual dimorphism in both aging and in response to drugs that modify the pace of aging.
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Affiliation(s)
- Lucas K Debarba
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, MI
| | - Hashan S M Jayarathne
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, MI
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, MI
| | - Michael Garratt
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, NZ
| | - Marianna Sadagurski
- Department of Biological Sciences, IBio (Integrative Biosciences Center), Wayne State University, Detroit, Michigan, MI
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14
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Koshko L, Debarba LK, Sacla M, Lima J, Didyuk O, Fakhoury P, Klueh U, Sadagurski M. In Utero Maternal Benzene Exposure Predisposes to the Metabolic Imbalance in the Offspring. J Endocr Soc 2021. [PMCID: PMC8089689 DOI: 10.1210/jendso/bvab048.898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Environmental chemicals play a significant role in the development of metabolic disorders, especially when exposure occurs early in life. We have recently demonstrated that benzene exposure, at concentrations relevant to a cigarette smoke, induces a severe metabolic imbalance in a sex-specific manner affecting male but not female mice. However, the roles of benzene in the development of aberrant metabolic outcomes following gestational exposure, remain largely unexplored. In this study, we exposed pregnant C57BL/6JB dams to benzene at 50 ppm or filtered air for 5 days/week (6h/day from gestational day 1 to birth) and studied male and female offspring metabolic phenotypes in their adult life. While no changes in body weight or body composition were observed between groups, 4-month-old male and female offspring exhibited reduced parameters of energy homeostasis (VO2, VCO2, and heat production). However, only male offspring from benzene-exposed dams were glucose intolerant and insulin resistant at this age. By six months of age, both male and female offspring displayed glucose and insulin intolerance, associated with elevated expression of hepatic gluconeogenesis and inflammatory genes. Additionally, this effect was accompanied by elevated insulin secretion and increased beta-cell mass only in male offspring. Thus, gestational benzene exposure can reprogram offspring for increased susceptibility to metabolic imbalance in adulthood with differential sensitivity between sexes.
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15
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de Lima JBM, Ubah C, Debarba LK, Ayyar I, Didyuk O, Sadagurski M. Hypothalamic GHR-SIRT1 Axis in Fasting. Cells 2021; 10:cells10040891. [PMID: 33919674 PMCID: PMC8069818 DOI: 10.3390/cells10040891] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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: 03/21/2021] [Revised: 04/11/2021] [Accepted: 04/13/2021] [Indexed: 01/06/2023] Open
Abstract
Many aspects of physiological functions are controlled by the hypothalamus, a brain region that connects the neuroendocrine system to whole-body metabolism. Growth hormone (GH) and the GH receptor (GHR) are expressed in hypothalamic regions known to participate in the regulation of feeding and whole-body energy homeostasis. Sirtuin 1 (SIRT1) is the most conserved mamma-lian nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase that plays a key role in controlling life span and sensing nutrient availability in the hypothalamus in response to caloric restriction. However, the interaction between GHR signaling and SIRT1 in the hypothal-amus is not established. In the arcuate nucleus (ARC) of the hypothalamus, the anorexigenic proopiomelanocortin (POMC)-expressing neurons and the orexigenic agouti-related protein (AgRP)-expressing neurons are the major regulators of feeding and energy expenditure. We show that in the ARC, the majority of GHR-expressing neurons also express SIRT1 and respond to fasting by upregulating SIRT1 expression. Accordingly, hypothalamic upregulation of SIRT1 in response to fasting is blunted in animals with GHR deletion in the AgRP neurons (AgRPEYFPΔGHR). Our data thus reveal a novel interaction between GH and SIRT1 in responses to fasting.
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16
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Koshko L, Debarba LK, Sacla M, de Lima JBM, Didyuk O, Fakhoury P, Sadagurski M. In Utero Maternal Benzene Exposure Predisposes to the Metabolic Imbalance in the Offspring. Toxicol Sci 2021; 180:252-261. [PMID: 33502539 DOI: 10.1093/toxsci/kfab010] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Environmental chemicals play a significant role in the development of metabolic disorders, especially when exposure occurs early in life. We have recently demonstrated that benzene exposure, at concentrations relevant to cigarette smoke, induces a severe metabolic imbalance in a sex-specific manner affecting male but not female mice. However, the roles of benzene in the development of aberrant metabolic outcomes following gestational exposure, remain largely unexplored. In this study, we exposed pregnant C57BL/6JB dams to benzene at 50 ppm or filtered air for 6 h/day from gestational day 0.5 (GD0.5) through GD21 and studied male and female offspring metabolic phenotypes in their adult life. While no changes in body weight or body composition were observed between groups, 4-month-old male and female offspring exhibited reduced parameters of energy homeostasis (VO2, VCO2, and heat production). However, only male offspring from benzene-exposed dams were glucose intolerant and insulin resistant at this age. By 6 months of age, both male and female offspring exhibited marked glucose intolerance however, only male offspring developed severe insulin resistance. This effect was accompanied by elevated insulin secretion and increased beta-cell mass only in male offspring. In support, Homeostatic Model Assessment for Insulin Resistance, the index of insulin resistance was elevated only in male but not in female offspring. Regardless, both male and female offspring exhibited a considerable increase in hepatic gene expression associated with inflammation and endoplasmic reticulum stress. Thus, gestational benzene exposure can predispose offspring to increased susceptibility to the metabolic imbalance in adulthood with differential sensitivity between sexes.
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Affiliation(s)
- Lisa Koshko
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
| | - Lucas K Debarba
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
| | - Mikaela Sacla
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
| | - Juliana B M de Lima
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
| | - Olesya Didyuk
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
| | - Patrick Fakhoury
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
| | - Marianna Sadagurski
- Department of Biological Sciences, Integrative Biosciences Center (IBio), Wayne State University, Detroit, Michigan 48202, USA
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17
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Miller RA, Harrison DE, Allison DB, Bogue M, Debarba L, Diaz V, Fernandez E, Galecki A, Garvey WT, Jayarathne H, Kumar N, Javors MA, Ladiges WC, Macchiarini F, Nelson J, Reifsnyder P, Rosenthal NA, Sadagurski M, Salmon AB, Smith DL, Snyder JM, Lombard DB, Strong R. Canagliflozin extends life span in genetically heterogeneous male but not female mice. JCI Insight 2020; 5:140019. [PMID: 32990681 PMCID: PMC7710304 DOI: 10.1172/jci.insight.140019] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 09/23/2020] [Indexed: 12/22/2022] Open
Abstract
Canagliflozin (Cana) is an FDA-approved diabetes drug that protects against cardiovascular and kidney diseases. It also inhibits the sodium glucose transporter 2 by blocking renal reuptake and intestinal absorption of glucose. In the context of the mouse Interventions Testing Program, genetically heterogeneous mice were given chow containing Cana at 180 ppm at 7 months of age until their death. Cana extended median survival of male mice by 14%. Cana also increased by 9% the age for 90th percentile survival, with parallel effects seen at each of 3 test sites. Neither the distribution of inferred cause of death nor incidental pathology findings at end-of-life necropsies were altered by Cana. Moreover, although no life span benefits were seen in female mice, Cana led to lower fasting glucose and improved glucose tolerance in both sexes, diminishing fat mass in females only. Therefore, the life span benefit of Cana is likely to reflect blunting of peak glucose levels, because similar longevity effects are seen in male mice given acarbose, a diabetes drug that blocks glucose surges through a distinct mechanism, i.e., slowing breakdown of carbohydrate in the intestine. Interventions that control daily peak glucose levels deserve attention as possible preventive medicines to protect from a wide range of late-life neoplastic and degenerative diseases. The SGLT2 inhibitor canagliflozin extends median life span of male mice but does not increase life span of female mice.
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Affiliation(s)
- Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, USA
| | | | - David B Allison
- Department of Epidemiology and Biostatistics, Indiana University School of Public Health, Bloomington, Indiana, USA
| | - Molly Bogue
- The Jackson Laboratory, Bar Harbor, Maine, USA
| | - Lucas Debarba
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, Michigan, USA
| | - Vivian Diaz
- Sam and Ann Barshop Institute for Longevity and Aging Studies and Departments of Physiology and Molecular Medicine, UT Health San Antonio, San Antonio, Texas, USA; South Texas Veterans Healthcare System, San Antonio, Texas, USA
| | - Elizabeth Fernandez
- Sam and Ann Barshop Institute for Longevity and Aging Studies and Departments of Physiology and Molecular Medicine, UT Health San Antonio, San Antonio, Texas, USA; South Texas Veterans Healthcare System, San Antonio, Texas, USA
| | - Andrzej Galecki
- Departments of Internal Medicine and Biostatistics, University of Michigan School of Medicine and School of Public Health, Ann Arbor, Michigan, USA
| | - W Timothy Garvey
- Department of Nutrition Sciences and Diabetes Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA; Birmingham VA Medical Center, Birmingham, Alabama, USA
| | - Hashan Jayarathne
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, Michigan, USA
| | - Navasuja Kumar
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
| | - Martin A Javors
- Department of Psychiatry, University of Texas Health Science Center, San Antonio, Texas, USA
| | - Warren C Ladiges
- Department of Comparative Medicine, University of Washington, Seattle, Washington, USA
| | | | - James Nelson
- Sam and Ann Barshop Institute for Longevity and Aging Research and Department of Cellular and Integrative Physiology, UT Health San Antonio, San Antonio, Texas, USA
| | | | | | - Marianna Sadagurski
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, Michigan, USA
| | - Adam B Salmon
- Sam and Ann Barshop Institute for Longevity and Aging Studies and Departments of Physiology and Molecular Medicine, UT Health San Antonio, San Antonio, Texas, USA; South Texas Veterans Healthcare System, San Antonio, Texas, USA
| | - Daniel L Smith
- Department of Nutrition Sciences and Nutrition Obesity Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jessica M Snyder
- Department of Comparative Medicine, University of Washington, Seattle, Washington, USA
| | - David B Lombard
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Randy Strong
- Sam and Ann Barshop Institute for Longevity and Aging Studies and Departments of Physiology and Molecular Medicine, UT Health San Antonio, San Antonio, Texas, USA; South Texas Veterans Healthcare System, San Antonio, Texas, USA
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18
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Debarba LK, Mulka A, Lima JBM, Didyuk O, Fakhoury P, Koshko L, Awada AA, Zhang K, Klueh U, Sadagurski M. Acarbose protects from central and peripheral metabolic imbalance induced by benzene exposure. Brain Behav Immun 2020; 89:87-99. [PMID: 32505715 DOI: 10.1016/j.bbi.2020.05.073] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 05/19/2020] [Accepted: 05/28/2020] [Indexed: 02/08/2023] Open
Abstract
Benzene is a well-known human carcinogen that is one of the major components of air pollution. Sources of benzene in ambient air include cigarette smoke, e-cigarettes vaping, and evaporation of benzene containing petrol processes. While the carcinogenic effects of benzene exposure have been well studied, less is known about the metabolic effects of benzene exposure. We show that chronic exposure to benzene at low levels induces a severe metabolic imbalance in a sex-specific manner, and is associated with hypothalamic inflammation and endoplasmic reticulum (ER) stress. Benzene exposure rapidly activates hypothalamic ER stress and neuroinflammatory responses in male mice, while pharmacological inhibition of ER stress response by inhibiting IRE1α-XBP1 pathway significantly alleviates benzene-induced glial inflammatory responses. Additionally, feeding mice with Acarbose, a clinically available anti-diabetes drug, protected against benzene induced central and peripheral metabolic imbalance. Acarbose imitates the slowing of dietary carbohydrate digestion, suggesting that choosing a diet with a low glycemic index might be a potential strategy for reducing the negative metabolic effect of chronic exposure to benzene for smokers or people living/working in urban environments with high concentrations of exposure to automobile exhausts.
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Affiliation(s)
- L K Debarba
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - A Mulka
- Biomedical Engineering, IBio (Integrative Biosciences Center), Wayne State University, Detroit, MI, United States
| | - J B M Lima
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - O Didyuk
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - P Fakhoury
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - L Koshko
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - A A Awada
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - K Zhang
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
| | - U Klueh
- Biomedical Engineering, IBio (Integrative Biosciences Center), Wayne State University, Detroit, MI, United States
| | - M Sadagurski
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States.
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19
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Sutton AK, Gonzalez IE, Sadagurski M, Rajala M, Lu C, Allison MB, Adams JM, Myers MG, White MF, Olson DP. Paraventricular, subparaventricular and periventricular hypothalamic IRS4-expressing neurons are required for normal energy balance. Sci Rep 2020; 10:5546. [PMID: 32218485 PMCID: PMC7099088 DOI: 10.1038/s41598-020-62468-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 03/12/2020] [Indexed: 02/07/2023] Open
Abstract
Understanding the neural components modulating feeding-related behavior and energy expenditure is crucial to combating obesity and its comorbidities. Neurons within the paraventricular nucleus of the hypothalamus (PVH) are a key component of the satiety response; activation of the PVH decreases feeding and increases energy expenditure, thereby promoting negative energy balance. In contrast, PVH ablation or silencing in both rodents and humans leads to substantial obesity. Recent studies have identified genetically-defined PVH subpopulations that control discrete aspects of energy balance (e.g. oxytocin (OXT), neuronal nitric oxide synthase 1 (NOS1), melanocortin 4-receptor (MC4R), prodynorphin (PDYN)). We previously demonstrated that non-OXT NOS1PVH neurons contribute to PVH-mediated feeding suppression. Here, we identify and characterize a non-OXT, non-NOS1 subpopulation of PVH and peri-PVH neurons expressing insulin-receptor substrate 4 (IRS4PVH) involved in energy balance control. Using Cre-dependent viral tools to activate, trace and silence these neurons, we highlight the sufficiency and necessity of IRS4PVH neurons in normal feeding and energy expenditure regulation. Furthermore, we demonstrate that IRS4PVH neurons lie within a complex hypothalamic circuitry that engages distinct hindbrain regions and is innervated by discrete upstream hypothalamic sites. Overall, we reveal a requisite role for IRS4PVH neurons in PVH-mediated energy balance which raises the possibility of developing novel approaches targeting IRS4PVH neurons for anti-obesity therapies.
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Affiliation(s)
- Amy K Sutton
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Ian E Gonzalez
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | | | - Michael Rajala
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Chunxia Lu
- Division of Pediatric Endocrinology, Department of Pediatrics, Michigan Medicine, Ann Arbor, MI, USA
| | - Margaret B Allison
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Jessica M Adams
- Division of Pediatric Endocrinology, Department of Pediatrics, Michigan Medicine, Ann Arbor, MI, USA
| | - Martin G Myers
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA.,Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Morris F White
- Department of Endocrinology, Children's Hospital Boston, Boston, MA, USA
| | - David P Olson
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA. .,Division of Pediatric Endocrinology, Department of Pediatrics, Michigan Medicine, Ann Arbor, MI, USA.
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20
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Sadagurski M, Debarba LK, Werneck-de-Castro JP, Ali Awada A, Baker TA, Bernal-Mizrachi E. Sexual dimorphism in hypothalamic inflammation in the offspring of dams exposed to a diet rich in high fat and branched-chain amino acids. Am J Physiol Endocrinol Metab 2019; 317:E526-E534. [PMID: 31361548 PMCID: PMC6766606 DOI: 10.1152/ajpendo.00183.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Branched-chain amino acid (BCAAs: leucine, isoleucine, and valine) contribute to the development of obesity-associated insulin resistance in the context of consumption of a high-fat diet (HFD) in humans and rodents. Maternal diet is a major determinant of offspring health, and there is strong evidence that maternal HFD alters hypothalamic developmental programming and disrupts offspring energy homeostasis in rodents. In this study, we exposed pregnant and lactating C57BL/6JB female mice to either HFD, HFD with supplemented BCAA (HFD+BCAA), or standard diet (SC), and we studied offspring metabolic phenotypes. Both maternal HFD and HFD supplemented with BCAA had similar effect rendering the offspring metabolic imbalance and impairing their ability to cope with HFD when challenged during aging. The metabolic effects of HFD challenge were more profound in females, worsening female offspring ability to cope with an HFD challenge by activating hypothalamic inflammation in aging. Moreover, the sex differences in hypothalamic estrogen receptor α (ER-α) expression levels were lost in female offspring upon HFD challenge, supporting a link between ER-α levels and hypothalamic inflammation in offspring and highlighting the programming potential of hypothalamic inflammatory responses and maternal nutrition.
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Affiliation(s)
- Marianna Sadagurski
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, Michigan
| | - Lucas Kniess Debarba
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, Michigan
| | - Joao Pedro Werneck-de-Castro
- Division of Endocrinology, Diabetes and Metabolism, Diabetes Research Institute, University of Miami, Miller School of Medicine, Miami, Florida
| | - Abear Ali Awada
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, Michigan
| | - Tess A Baker
- Division of Endocrinology, Diabetes and Metabolism, Diabetes Research Institute, University of Miami, Miller School of Medicine, Miami, Florida
| | - Ernesto Bernal-Mizrachi
- Division of Endocrinology, Diabetes and Metabolism, Diabetes Research Institute, University of Miami, Miller School of Medicine, Miami, Florida
- Miami Veterans Affairs Health Care System, Miami, Florida
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21
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Debarba L, Mulka A, Awada A, Didyuk O, Marcus D, Klueh U, Sadagurski M. SAT-179 Low Grade Benzene Exposure Induces Metabolic Dysbalance and Hypothalamic Inflammation in Mice. J Endocr Soc 2019. [PMCID: PMC6551737 DOI: 10.1210/js.2019-sat-179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Type 2-diabetes mellitus (T2D) has become a global pandemic resulting in a reduced quality of life due to comorbidity and premature mortality. The World Health Organization estimates the current global prevalence at 8.4%, which represents a fourfold increase over the last four decades. In this same interval, the US prevalence has increased by 160%, such that it affects 1 in 11 Americans with a disproportionate impact on minorities. The choice of lifestyle, diet, lack of physical activity and the growing aging population is often used to explain the rise of the diabetes pandemic. However, it is now increasingly accepted that insulin resistance, T2D prevalence and mortality have been associated with long- term exposure to air and traffic pollution. Benzene is a highly volatile liquid, which is a constituent of crude petroleum. Given its ubiquitous utilization in industry as well as consumer products, it is classified as a common airborne pollutant. As such, any exposure to petroleum or its products can result in significant occupational benzene exposure. While it is well accepted that excessive benzene exposure is carcinogenic in animals and humans, little is known regarding the effect of non-carcinogenic benzene level exposure and its metabolic effects. Notably, benzene exposure from motor vehicle exhaust is higher in inner city populations, which suggests a causative role in the pathogenesis of T2D. We hypothesized that benzene, at levels below carcinogenic contributes to insulin resistance and inflammatory responses linking persistent organic pollutants (POP) exposure to type 2 diabetes mellitus. For this purpose, C57BL/6 mice in inhalation chambers were exposed to benzene concentration of 50 ppm for 6h/day for 4 weeks. We found that under these conditions, exposure to benzene did not significantly change male mice body weight, neither had it trigger any toxic responses in these animals. However, despite normal fasting glucose and insulin levels, glucose tolerance test (GTT) of benzene exposed male mice displayed significantly impaired IP glucose tolerance. Consequently, we detected an increase in hepatic genes associated with gluconeogenesis, G6Pase and Pck1, and the expression of SREBP-1c and SREBP-2, genes associated with lipid synthesis was significantly elevated in livers from benzene exposed mice as compared to control mice. Additionally, we detected significant neuroinflammatory response in the hypothalamus of benzene exposed mice. Benzene exposure promoted a significant increase on microglia and astrocytes numbers in the arcuate, ventromedial and dorsomedial hypothalamic nucleus. We conclude that exposure to benzene induces hyperglycemia and that hypothalamic inflammatory responses may be a sensitive indicator of inhaled benzene toxicity.
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Affiliation(s)
| | - Adam Mulka
- Wayne State University, Detroit, MI, United States
| | - Abear Awada
- Wayne State University, Detroit, MI, United States
| | | | | | - Ulrike Klueh
- Wayne State University, Detroit, MI, United States
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22
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Cady G, Sadagurski M. Targeting neuroinflammation - a potential for anti-aging interventions. Aging (Albany NY) 2019; 9:1951-1952. [PMID: 28952452 PMCID: PMC5636665 DOI: 10.18632/aging.101296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 09/20/2017] [Indexed: 01/24/2023]
Affiliation(s)
- Gillian Cady
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, MI 48202, USA
| | - Marianna Sadagurski
- Department of Biological Sciences, Integrative Biosciences Center, Wayne State University, Detroit, MI 48202, USA
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23
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Abstract
Aging leads to hypothalamic inflammation, but does so more slowly in mice whose lifespan has been extended by mutations that affect GH/IGF‐1 signals. Early‐life exposure to GH by injection, or to nutrient restriction in the first 3 weeks of life, also modulate both lifespan and the pace of hypothalamic inflammation. Three drugs extend lifespan of UM‐HET3 mice in a sex‐specific way: acarbose (ACA), 17‐α‐estradiol (17αE2), and nordihydroguaiaretic acid (NDGA), with more dramatic longevity increases in males in each case. In this study, we examined the effect of these anti‐aging drugs on neuro‐inflammation in hypothalamus and hippocampus. We found that age‐associated hypothalamic inflammation is reduced in males but not in females at 12 months of age by ACA and 17αE2 and at 22 months of age in NDGA‐treated mice. The three drugs blocked indices of hypothalamic reactive gliosis associated with aging, such as Iba‐1‐positive microglia and GFAP‐positive astrocytes, as well as age‐associated overproduction of TNF‐α. This effect was not observed in drug‐treated female mice or in the hippocampus of the drug‐treated animals. On the other hand, caloric restriction (CR; an intervention that extends the lifespan in both sexes) significantly reduced hypothalamic microglia and TNF‐α in both sexes at 12 months of age. Together, these results suggest that the extent of drug‐induced changes in hypothalamic inflammatory processes is sexually dimorphic in a pattern that parallels the effects of these agents on mouse longevity and that mimics the changes seen, in both sexes, of long‐lived nutrient restricted or mutant mice.
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Affiliation(s)
- Marianna Sadagurski
- Division of Geriatric and Palliative Medicine; Department of Internal Medicine; University of Michigan; Ann Arbor MI USA
| | - Gillian Cady
- Department of Pathology and Geriatrics Center; University of Michigan; Ann Arbor MI USA
| | - Richard A. Miller
- Department of Pathology and Geriatrics Center; University of Michigan; Ann Arbor MI USA
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24
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Cady G, Landeryou T, Garratt M, Kopchick JJ, Qi N, Garcia-Galiano D, Elias CF, Myers MG, Miller RA, Sandoval DA, Sadagurski M. Hypothalamic growth hormone receptor (GHR) controls hepatic glucose production in nutrient-sensing leptin receptor (LepRb) expressing neurons. Mol Metab 2017; 6:393-405. [PMID: 28462074 PMCID: PMC5404104 DOI: 10.1016/j.molmet.2017.03.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 02/28/2017] [Accepted: 03/04/2017] [Indexed: 12/22/2022] Open
Abstract
Objective The GH/IGF-1 axis has important roles in growth and metabolism. GH and GH receptor (GHR) are active in the central nervous system (CNS) and are crucial in regulating several aspects of metabolism. In the hypothalamus, there is a high abundance of GH-responsive cells, but the role of GH signaling in hypothalamic neurons is unknown. Previous work has demonstrated that the Ghr gene is highly expressed in LepRb neurons. Given that leptin is a key regulator of energy balance by acting on leptin receptor (LepRb)-expressing neurons, we tested the hypothesis that LepRb neurons represent an important site for GHR signaling to control body homeostasis. Methods To determine the importance of GHR signaling in LepRb neurons, we utilized Cre/loxP technology to ablate GHR expression in LepRb neurons (LeprEYFPΔGHR). The mice were generated by crossing the Leprcre on the cre-inducible ROSA26-EYFP mice to GHRL/L mice. Parameters of body composition and glucose homeostasis were evaluated. Results Our results demonstrate that the sites with GHR and LepRb co-expression include ARH, DMH, and LHA neurons. Leptin action was not altered in LeprEYFPΔGHR mice; however, GH-induced pStat5-IR in LepRb neurons was significantly reduced in these mice. Serum IGF-1 and GH levels were unaltered, and we found no evidence that GHR signaling regulates food intake and body weight in LepRb neurons. In contrast, diminished GHR signaling in LepRb neurons impaired hepatic insulin sensitivity and peripheral lipid metabolism. This was paralleled with a failure to suppress expression of the gluconeogenic genes and impaired hepatic insulin signaling in LeprEYFPΔGHR mice. Conclusion These findings suggest the existence of GHR-leptin neurocircuitry that plays an important role in the GHR-mediated regulation of glucose metabolism irrespective of feeding. GHR and LepRb are co-localized in the ARH, DMH and LHA neurons. GHR signaling does not regulate food intake and body weight in LepRb neurons. Diminished GHR signaling in LepRb neurons impairs hepatic glucose production.
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Key Words
- ARH, arcuate nucleus of the hypothalamus
- CNS, central nervous system
- DMH, dorsomedial hypothalamic nucleus
- GH, growth hormone
- GHR, growth hormone receptor
- Glucose production
- Growth hormone receptor
- Hypothalamus
- LHA, lateral hypothalamus
- Lepr, leptin receptor
- Leptin receptor
- Liver
- POMC, proopiomelanocortin
- PVH, paraventricular hypothalamic nucleus
- Stat3, signal transducer and activator of transcription 3
- Stat5, signal transducer and activator of transcription 5
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Affiliation(s)
- Gillian Cady
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - Taylor Landeryou
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - Michael Garratt
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | - Nathan Qi
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - David Garcia-Galiano
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Carol F Elias
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Martin G Myers
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan Medical School, USA
| | - Darleen A Sandoval
- Department of Surgery, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Marianna Sadagurski
- Division of Geriatric and Palliative Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA.
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Kuznetsova A, Yu Y, Hollister-Lock J, Opare-Addo L, Rozzo A, Sadagurski M, Norquay L, Reed JE, El Khattabi I, Bonner-Weir S, Weir GC, Sharma A, White MF. Trimeprazine increases IRS2 in human islets and promotes pancreatic β cell growth and function in mice. JCI Insight 2016; 1. [PMID: 27152363 PMCID: PMC4854304 DOI: 10.1172/jci.insight.80749] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The capacity of pancreatic β cells to maintain glucose homeostasis during chronic physiologic and immunologic stress is important for cellular and metabolic homeostasis. Insulin receptor substrate 2 (IRS2) is a regulated adapter protein that links the insulin and IGF1 receptors to downstream signaling cascades. Since strategies to maintain or increase IRS2 expression can promote β cell growth, function, and survival, we conducted a screen to find small molecules that can increase IRS2 mRNA in isolated human pancreatic islets. We identified 77 compounds, including 15 that contained a tricyclic core. To establish the efficacy of our approach, one of the tricyclic compounds, trimeprazine tartrate, was investigated in isolated human islets and in mouse models. Trimeprazine is a first-generation antihistamine that acts as a partial agonist against the histamine H1 receptor (H1R) and other GPCRs, some of which are expressed on human islets. Trimeprazine promoted CREB phosphorylation and increased the concentration of IRS2 in islets. IRS2 was required for trimeprazine to increase nuclear Pdx1, islet mass, β cell replication and function, and glucose tolerance in mice. Moreover, trimeprazine synergized with anti-CD3 Abs to reduce the progression of diabetes in NOD mice. Finally, it increased the function of human islet transplants in streptozotocin-induced (STZ-induced) diabetic mice. Thus, trimeprazine, its analogs, or possibly other compounds that increase IRS2 in islets and β cells without adverse systemic effects might provide mechanism-based strategies to prevent the progression of diabetes.
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Affiliation(s)
- Alexandra Kuznetsova
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Yue Yu
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jennifer Hollister-Lock
- Section of Islet Cell and Regenerative Biology, Department of Medicine, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Lynn Opare-Addo
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Aldo Rozzo
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Marianna Sadagurski
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Lisa Norquay
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Jessica E Reed
- Housey Pharmaceutical Research Laboratories, Southfield, Michigan, USA
| | - Ilham El Khattabi
- Section of Islet Cell and Regenerative Biology, Department of Medicine, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Susan Bonner-Weir
- Section of Islet Cell and Regenerative Biology, Department of Medicine, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Gordon C Weir
- Section of Islet Cell and Regenerative Biology, Department of Medicine, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Arun Sharma
- Section of Islet Cell and Regenerative Biology, Department of Medicine, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Morris F White
- Division of Endocrinology, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Sadagurski M, Landeryou T, Cady G, Kopchick JJ, List EO, Berryman DE, Bartke A, Miller RA. Growth hormone modulates hypothalamic inflammation in long-lived pituitary dwarf mice. Aging Cell 2015; 14:1045-54. [PMID: 26268661 PMCID: PMC4693470 DOI: 10.1111/acel.12382] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/15/2015] [Indexed: 12/11/2022] Open
Abstract
Mice in which the genes for growth hormone (GH) or GH receptor (GHR(-/-) ) are disrupted from conception are dwarfs, possess low levels of IGF-1 and insulin, have low rates of cancer and diabetes, and are extremely long-lived. Median longevity is also increased in mice with deletion of hypothalamic GH-releasing hormone (GHRH), which leads to isolated GH deficiency. The remarkable extension of longevity in hypopituitary Ames dwarf mice can be reversed by a 6-week course of GH injections started at the age of 2 weeks. Here, we demonstrate that mutations that interfere with GH production or response, in the Snell dwarf, Ames dwarf, or GHR(-/-) mice lead to reduced formation of both orexigenic agouti-related peptide (AgRP) and anorexigenic proopiomelanocortin (POMC) projections to the main hypothalamic projection areas: the arcuate nucleus (ARH), paraventricular nucleus (PVH), and dorsomedial nucleus (DMH). These mutations also reduce hypothalamic inflammation in 18-month-old mice. GH injections, between 2 and 8 weeks of age, reversed both effects in Ames dwarf mice. Disruption of GHR specifically in liver (LiGHRKO), a mutation that reduces circulating IGF-1 but does not lead to lifespan extension, had no effect on hypothalamic projections or inflammation, suggesting an effect of GH, rather than peripheral IGF-1, on hypothalamic development. Hypothalamic leptin signaling, as monitored by induction of pStat3, is not impaired by GHR deficiency. Together, these results suggest that early-life disruption of GH signaling produces long-term hypothalamic changes that may contribute to the longevity of GH-deficient and GH-resistant mice.
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Affiliation(s)
- Marianna Sadagurski
- Department of Internal Medicine Division of Geriatric and Palliative Medicine University of Michigan Ann Arbor MI USA
| | - Taylor Landeryou
- Department of Pathology and Geriatrics Center University of Michigan Ann Arbor MI USA
| | - Gillian Cady
- Department of Pathology and Geriatrics Center University of Michigan Ann Arbor MI USA
| | | | - Edward O. List
- Edison Biotechnology Institute Ohio University Athens OH USA
| | | | - Andrzej Bartke
- Department of Internal Medicine–Geriatrics Research Southern Illinois University School of Medicine Springfield IL USA
| | - Richard A. Miller
- Department of Pathology and Geriatrics Center University of Michigan Ann Arbor MI USA
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Sadagurski M, Landeryou T, Cady G, Bartke A, Bernal-Mizrachi E, Miller RA. Transient early food restriction leads to hypothalamic changes in the long-lived crowded litter female mice. Physiol Rep 2015; 3:3/4/e12379. [PMID: 25907790 PMCID: PMC4425981 DOI: 10.14814/phy2.12379] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Transient nutrient restriction in the 3 weeks between birth and weaning (producing “crowded litter” or CL mice) leads to a significant increase in lifespan and is associated with permanent changes in energy homeostasis, leptin, and insulin sensitivity. Here, we show this brief period of early food restriction leads to permanent modulation of the arcuate nucleus of the hypothalamus (ARH), markedly increasing formation of both orexigenic agouti-related peptide (AgRP) and anorexigenic proopiomelanocortin (POMC) projections to the paraventricular nucleus of the hypothalamus (PVH). An additional 4 weeks of caloric restriction, after weaning, does not further intensify the formation of AgRP and POMC projections. Acute leptin stimulation of 12-month-old mice leads to a stronger increase in the levels of hypothalamic pStat3 and cFos activity in CL mice than in controls, suggesting that preweaning food restriction leads to long-lasting enhancement of leptin signaling. In contrast, FoxO1 nuclear exclusion in response to insulin is equivalent in young adult CL and control mice, suggesting that hypothalamic insulin signaling is not modulated by the crowded litter intervention. Markers of hypothalamic reactive gliosis associated with aging, such as Iba1-positive microglia and GFAP-positive astrocytes, are significantly reduced in CL mice as compared to controls at 12 and 22 months of age. Lastly, age-associated overproduction of TNF-α in microglial cells is reduced in CL mice than in age-matched controls. Together, these results suggest that transient early life nutrient deprivation leads to long-term hypothalamic changes which may contribute to the longevity of CL mice.
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Affiliation(s)
- Marianna Sadagurski
- Division of Geriatric and Palliative Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan
| | - Taylor Landeryou
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan
| | - Gillian Cady
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan
| | - Andrzej Bartke
- Department of Internal Medicine-Geriatrics Research, Southern Illinois University School of Medicine, Springfield, Illinois
| | - Ernesto Bernal-Mizrachi
- Division of Metabolism Endocrinology and Diabetes, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan Endocrinology Section, Medical Service, Veterans Affairs Medical Center, Ann Arbor, Michigan
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan
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Sadagurski M, Landeryou T, Blandino-Rosano M, Cady G, Elghazi L, Meister D, See L, Bartke A, Bernal-Mizrachi E, Miller RA. Long-lived crowded-litter mice exhibit lasting effects on insulin sensitivity and energy homeostasis. Am J Physiol Endocrinol Metab 2014; 306:E1305-14. [PMID: 24735888 PMCID: PMC4042097 DOI: 10.1152/ajpendo.00031.2014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The action of nutrients on early postnatal growth can influence mammalian aging and longevity. Recent work has demonstrated that limiting nutrient availability in the first 3 wk of life [by increasing the number of pups in the crowded-litter (CL) model] leads to extension of mean and maximal lifespan in genetically normal mice. In this study, we aimed to characterize the impact of early-life nutrient intervention on glucose metabolism and energy homeostasis in CL mice. In our study, we used mice from litters supplemented to 12 or 15 pups and compared those to control litters limited to eight pups. At weaning and then throughout adult life, CL mice are significantly leaner and consume more oxygen relative to control mice. At 6 mo of age, CL mice had low fasting leptin concentrations, and low-dose leptin injections reduced body weight and food intake more in CL female mice than in controls. At 22 mo, CL female mice also have smaller adipocytes compared with controls. Glucose and insulin tolerance tests show an increase in insulin sensitivity in 6 mo old CL male mice, and females become more insulin sensitive later in life. Furthermore, β-cell mass was significantly reduced in the CL male mice and was associated with reduction in β-cell proliferation rate in these mice. Together, these data show that early-life nutrient intervention has a significant lifelong effect on metabolic characteristics that may contribute to the increased lifespan of CL mice.
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Affiliation(s)
- Marianna Sadagurski
- Department of Internal Medicine, Division of Geriatric and Palliative Medicine, University of Michigan, Ann Arbor, Michigan;
| | - Taylor Landeryou
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan
| | - Manuel Blandino-Rosano
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan
| | - Gillian Cady
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan
| | - Lynda Elghazi
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan
| | - Daniel Meister
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan
| | - Lauren See
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan
| | - Andrzej Bartke
- Department of Internal Medicine-Geriatrics Research, Southern Illinois University School of Medicine, Springfield, Illinois; and
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division of Metabolism, Endocrinology and Diabetes, University of Michigan, Ann Arbor, Michigan; Endocrinology Section, Medical Service, Veterans Affairs Medical Center, Ann Arbor, Michigan
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, Michigan
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Abstract
The insulin pathway coordinates growth, development, metabolic homoeostasis, fertility, and stress resistance, which influence life span. Compensatory hyperinsulinemia to overcome systemic insulin resistance circumvents the immediate consequences of hyperglycemia. Work on flies, nematodes, and mice indicate that excess insulin signaling damages cellular function and accelerates aging. Maintenance of the central nervous system (CNS) has particular importance for life span. Reduced insulin/IGF1 signaling in the CNS can dysregulate peripheral energy homeostasis and metabolism, promote obesity, and extend life span. Genetic manipulations of insulin/IGF1 signaling components are revealing neuronal circuits that might resolve the central regulation of systemic metabolism from organism longevity.
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Affiliation(s)
- Marianna Sadagurski
- Department of Endocrinology, Children's Hospital Boston, Howard Hughes Medical Institute, Boston, MA 02115, USA
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30
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Sadagurski M, Leshan RL, Patterson C, Rozzo A, Kuznetsova A, Skorupski J, Jones JC, Depinho RA, Myers MG, White MF. IRS2 signaling in LepR-b neurons suppresses FoxO1 to control energy balance independently of leptin action. Cell Metab 2012; 15:703-12. [PMID: 22560222 PMCID: PMC3361909 DOI: 10.1016/j.cmet.2012.04.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 02/15/2012] [Accepted: 04/13/2012] [Indexed: 01/17/2023]
Abstract
Irs2-mediated insulin/IGF1 signaling in the CNS modulates energy balance and glucose homeostasis; however, the site for Irs2 function is unknown. The hormone leptin mediates energy balance by acting on leptin receptor (LepR-b)-expressing neurons. To determine whether LepR-b neurons mediate the metabolic actions of Irs2 in the brain, we utilized Lepr(cre) together with Irs2(L/L) to ablate Irs2 expression in LepR-b neurons (Lepr(ΔIrs2)). Lepr(ΔIrs2) mice developed obesity, glucose intolerance, and insulin resistance. Leptin action was not altered in young Lepr(ΔIrs2) mice, although insulin-stimulated FoxO1 nuclear exclusion was reduced in Lepr(ΔIrs2) mice. Indeed, deletion of Foxo1 from LepR-b neurons in Lepr(ΔIrs2) mice normalized energy balance, glucose homeostasis, and arcuate nucleus gene expression. Thus, Irs2 signaling in LepR-b neurons plays a crucial role in metabolic sensing and regulation. While not required for leptin action, Irs2 suppresses FoxO1 signaling in LepR-b neurons to promote energy balance and metabolism.
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Affiliation(s)
- Marianna Sadagurski
- Howard Hughes Medical Institute, Division of Endocrinology Children's Hospital Boston Harvard Medical School Boston, Massachusetts, USA
| | - Rebecca L. Leshan
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Christa Patterson
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Aldo Rozzo
- Howard Hughes Medical Institute, Division of Endocrinology Children's Hospital Boston Harvard Medical School Boston, Massachusetts, USA
| | - Alexandra Kuznetsova
- Howard Hughes Medical Institute, Division of Endocrinology Children's Hospital Boston Harvard Medical School Boston, Massachusetts, USA
| | - Josh Skorupski
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Justin C. Jones
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Ronald A. Depinho
- Department of Cancer Biology University of Texas MD Anderson Cancer Center Houston, TX 77030
| | - Martin G. Myers
- Division of Metabolism, Endocrinology and Diabetes, Department of Internal Medicine and Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Morris F. White
- Howard Hughes Medical Institute, Division of Endocrinology Children's Hospital Boston Harvard Medical School Boston, Massachusetts, USA
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Sadagurski M, Cheng Z, Rozzo A, Palazzolo I, Kelley GR, Dong X, Krainc D, White MF. IRS2 increases mitochondrial dysfunction and oxidative stress in a mouse model of Huntington disease. J Clin Invest 2011; 121:4070-81. [PMID: 21926467 DOI: 10.1172/jci46305] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2011] [Accepted: 07/27/2011] [Indexed: 12/31/2022] Open
Abstract
Aging is a major risk factor for the progression of neurodegenerative diseases, including Huntington disease (HD). Reduced neuronal IGF1 or Irs2 signaling have been shown to extend life span in mice. To determine whether Irs2 signaling modulates neurodegeneration in HD, we genetically modulated Irs2 concentrations in the R6/2 mouse model of HD. Increasing Irs2 levels in the brains of R6/2 mice significantly reduced life span and increased neuronal oxidative stress and mitochondrial dysfunction. In contrast, reducing Irs2 levels throughout the body (except in β cells, where Irs2 expression is needed to prevent diabetes onset; R6/2•Irs2+/-•Irs2βtg mice) improved motor performance and extended life span. The slower progression of HD-like symptoms was associated with increased nuclear localization of the transcription factor FoxO1 and increased expression of FoxO1-dependent genes that promote autophagy, mitochondrial function, and resistance to oxidative stress. Mitochondrial function improved and the number of autophagosomes increased in R6/2•Irs2+/-•Irs2βtg mice, whereas aggregate formation and oxidative stress decreased. Thus, our study suggests that Irs2 signaling can modulate HD progression. Since we found the expression of Irs2 to be normal in grade II HD patients, our results suggest that decreasing IRS2 signaling could be part of a therapeutic approach to slow the progression of HD.
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Affiliation(s)
- Marianna Sadagurski
- Howard Hughes Medical Institute, Division of Endocrinology, Children's Hospital Boston, Boston, Massachusetts 02115, USA
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Carew RM, Sadagurski M, Goldschmeding R, Martin F, White MF, Brazil DP. Deletion of Irs2 causes reduced kidney size in mice: role for inhibition of GSK3beta? BMC Dev Biol 2010; 10:73. [PMID: 20604929 PMCID: PMC2910663 DOI: 10.1186/1471-213x-10-73] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Accepted: 07/06/2010] [Indexed: 11/10/2022]
Abstract
BACKGROUND Male Irs2-/- mice develop fatal type 2 diabetes at 13-14 weeks. Defects in neuronal proliferation, pituitary development and photoreceptor cell survival manifest in Irs2-/- mice. We identify retarded renal growth in male and female Irs2-/- mice, independent of diabetes. RESULTS Kidney size and kidney:body weight ratio were reduced by approximately 20% in Irs2-/- mice at postnatal day 5 and was maintained in maturity. Reduced glomerular number but similar glomerular density was detected in Irs2-/- kidney compared to wild-type, suggesting intact global kidney structure. Analysis of insulin signalling revealed renal-specific upregulation of PKBbeta/Akt2, hyperphosphorylation of GSK3beta and concomitant accumulation of beta-catenin in Irs2-/- kidney. Despite this, no significant upregulation of beta-catenin targets was detected. Kidney-specific increases in Yes-associated protein (YAP), a key driver of organ size were also detected in the absence of Irs2. YAP phosphorylation on its inhibitory site Ser127 was also increased, with no change in the levels of YAP-regulated genes, suggesting that overall YAP activity was not increased in Irs2-/- kidney. CONCLUSIONS In summary, deletion of Irs2 causes reduced kidney size early in mouse development. Compensatory mechanisms such as increased beta-catenin and YAP levels failed to overcome this developmental defect. These data point to Irs2 as an important novel mediator of kidney size.
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Affiliation(s)
- Rosemarie M Carew
- UCD Diabetes Research Centre, UCD Conway Institute, School of Medicine and Medical Science, University College Dublin, Belfield Dublin 4, Ireland
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Abstract
AIMS/HYPOTHESIS Interleukin-6 is an inflammatory cytokine with pleiotropic effects upon nutrient homeostasis. Many reports show that circulating IL6 correlates with obesity and contributes to insulin resistance; however, IL6 can promote energy expenditure that improves glucose homeostasis. METHODS We investigated nutrient homeostasis in C57BL/6J mice with sustained circulating human IL6 (hIL6) secreted predominantly from brain and lung (hIL6(tg) mice). RESULTS The hIL6(tg) mice displayed no features of systemic inflammation and were more insulin-sensitive than wild-type mice. On a high-fat diet, hIL6(tg) mice were lean, had low leptin concentrations, consumed less food and expended more energy than wild-type mice. Like ob/ob mice, the ob/ob (IL6) mice (generated by intercrossing ob/ob and hIL6(tg) mice) were obese and glucose-intolerant. However, low-dose leptin injections increased physical activity and reduced both body weight and food intake in ob/ob (IL6) mice, but was ineffective in ob/ob mice. Leptin increased hypothalamic signal transducer and activator of transcription-3 phosphorylation in ob/ob (IL6) mice, whereas ob/ob mice barely responded. CONCLUSIONS/INTERPRETATION Human IL6 enhanced central leptin action in mice, promoting nutrient homeostasis and preventing diet-induced obesity.
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Affiliation(s)
- M. Sadagurski
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital Boston, Harvard Medical School, Karp Family Research Laboratories, Rm 4210, 300 Longwood Avenue, Boston, MA 02115 USA
| | - L. Norquay
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital Boston, Harvard Medical School, Karp Family Research Laboratories, Rm 4210, 300 Longwood Avenue, Boston, MA 02115 USA
| | - J. Farhang
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital Boston, Harvard Medical School, Karp Family Research Laboratories, Rm 4210, 300 Longwood Avenue, Boston, MA 02115 USA
| | - K. D’Aquino
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital Boston, Harvard Medical School, Karp Family Research Laboratories, Rm 4210, 300 Longwood Avenue, Boston, MA 02115 USA
| | - K. Copps
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital Boston, Harvard Medical School, Karp Family Research Laboratories, Rm 4210, 300 Longwood Avenue, Boston, MA 02115 USA
| | - M. F. White
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital Boston, Harvard Medical School, Karp Family Research Laboratories, Rm 4210, 300 Longwood Avenue, Boston, MA 02115 USA
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Sadagurski M, Nofech-Mozes S, Weingarten G, White MF, Kadowaki T, Wertheimer E. Insulin receptor substrate 1 (IRS-1) plays a unique role in normal epidermal physiology. J Cell Physiol 2007; 213:519-27. [PMID: 17508357 DOI: 10.1002/jcp.21131] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Insulin receptor substrate (IRS) proteins play a central role in insulin signaling. Previously we have demonstrated that insulin is essential for normal skin development and function. In the present study we investigated the involvement of the IRS-1 and IRS-2 proteins in skin physiology and in mediating insulin action in skin. For this purpose we have investigated the effects of inactivation of each of the IRSs on skin, studying skin sections and primary skin cells derived from IRS-1 or IRS-2 null mice. We have demonstrated that while the skin of the IRS-2 null mice appeared normal, the skin of the IRS-1 null mice was thinner and translucent. Histological analysis revealed that the thinning of the IRS-1 null skin was a consequence of the thinning of the spinous compartment, consisting of fewer layers. Proliferation of the IRS-1 and IRS-2 null skin epidermal cells was normal. However, the differentiation process of the IRS-1 skin and skin cells was impaired. There was a marked decrease in the induction of the expression of K1, the marker of advanced stages of skin differentiation. In contrary, IRS-2 inactivation had no effects on skin differentiation. In conclusion, we have shown for the first time that IRS-1 but not IRS-2 has an effect on skin formation and development, being one of the main activators of the differentiation process in skin keratinocytes. Furthermore, we suggest that IRS-1 and IRS-2 have distinct roles in skin physiology.
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Affiliation(s)
- Marianna Sadagurski
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Sadagurski M, Yakar S, Weingarten G, Holzenberger M, Rhodes CJ, Breitkreutz D, Leroith D, Wertheimer E. Insulin-like growth factor 1 receptor signaling regulates skin development and inhibits skin keratinocyte differentiation. Mol Cell Biol 2006; 26:2675-87. [PMID: 16537911 PMCID: PMC1430337 DOI: 10.1128/mcb.26.7.2675-2687.2006] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The insulin-like growth factor 1 receptor (IGF-1R) is a multifunctional receptor that mediates signals for cell proliferation, differentiation, and survival. Genetic experiments showed that IGF-1R inactivation in skin results in a disrupted epidermis. However, because IGF-1R-null mice die at birth, it is difficult to study the effects of IGF-1R on skin. By using a combined approach of conditional gene ablation and a three-dimensional organotypic model, we demonstrate that IGF-1R-deficient skin cocultures show abnormal maturation and differentiation patterns. Furthermore, IGF-1R-null keratinocytes exhibit accelerated differentiation and decreased proliferation. Investigating the signaling pathway downstream of IGF-1R reveals that insulin receptor substrate 2 (IRS-2) overexpression compensates for the lack of IGF-1R, whereas IRS-1 overexpression does not. We also demonstrate that phosphatidylinositol 3-kinase and extracellular signal-regulated kinase 1 and 2 are involved in the regulation of skin keratinocyte differentiation and take some part in mediating the inhibitory signal of IGF-1R on differentiation. In addition, we show that mammalian target of rapamycin plays a specific role in mediating IGF-1R impedance of action on keratinocyte differentiation. In conclusion, these results reveal that IGF-1R plays an inhibitory role in the regulation of skin development and differentiation.
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Affiliation(s)
- Marianna Sadagurski
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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Sadagurski M, Weingarten G, Rhodes CJ, White MF, Wertheimer E. Insulin Receptor Substrate 2 Plays Diverse Cell-specific Roles in the Regulation of Glucose Transport. J Biol Chem 2005; 280:14536-44. [PMID: 15705592 DOI: 10.1074/jbc.m410227200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The insulin receptor substrate 2 (IRS-2) protein is one of the major insulin-signaling substrates. In the present study, we investigated the role of IRS-2 in skin epidermal keratinocytes and dermal fibroblasts. Although skin is not a classical insulin target tissue, we have previously demonstrated that insulin, via the insulin receptor, is essential for normal skin cell physiology. To identify the role of IRS-2 in skin cells, we studied cells isolated from IRS-2 knock-out (KO) mice. Whereas proliferation and differentiation were not affected in the IRS-2 KO cells, a striking effect was observed on glucose transport. In IRS-2 KO keratinocytes, the lack of IRS-2 resulted in a dramatic increase in basal and insulin-stimulated glucose transport. The increase in glucose transport was associated with an increase in total phosphatidylinositol (PI) 3-kinase and Akt activation. In contrast, fibroblasts lacking IRS-2 exhibited a significant decrease in basal and insulin-induced glucose transport. We identified the point of divergence, leading to these differences between keratinocytes and fibroblasts, at the IRS-PI 3-kinase association step. In epidermal keratinocytes, PI 3-kinase is associated with and activated by only the IRS-1 protein. On the other hand, in dermal fibroblasts, PI 3-kinase is exclusively associated with and activated by the IRS-2 protein. These observations suggest that IRS-2 functions as a negative or positive regulator of glucose transport in a cell-specific manner. Our results also show that IRS-2 function depends on its cell-specific association with PI 3-kinase.
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Affiliation(s)
- Marianna Sadagurski
- Department of Pathology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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