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Molinas AJR, Desmoulins LD, Hamling BV, Butcher SM, Anwar IJ, Miyata K, Enix CL, Dugas CM, Satou R, Derbenev AV, Zsombok A. Interaction between TRPV1-expressing neurons in the hypothalamus. J Neurophysiol 2019; 121:140-151. [PMID: 30461371 PMCID: PMC6383661 DOI: 10.1152/jn.00004.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 10/29/2018] [Accepted: 11/14/2018] [Indexed: 02/08/2023] Open
Abstract
Transient receptor potential vanilloid type 1 (TRPV1) is a ligand-gated ion channel expressed in the peripheral and central nervous systems. TRPV1-dependent mechanisms take part in a wide range of physiological and pathophysiological pathways including the regulation of homeostatic functions. TRPV1 expression in the hypothalamus has been described as well as evidence that TRPV1-dependent excitatory inputs to hypothalamic preautonomic neurons are diminished in diabetic conditions. Here we aimed to determine the functional expression of TRPV1 in two hypothalamic nuclei known to be involved in the central control of metabolism and to test the hypothesis that TRPV1-expressing neurons receive TRPV1-expressing inputs. A mouse model (TRPV1Cre/tdTom) was generated to identify TRPV1-expressing cells and determine the cellular properties of TRPV1-expressing neurons in adult mice. Our study demonstrated the functional expression of TRPV1 in the dorsomedial hypothalamic nucleus and paraventricular nucleus in adult mice. Our findings revealed that a subset of TRPV1Cre/tdTom neurons receive TRPV1-expressing excitatory inputs, indicating direct interaction between TRPV1-expressing neurons. In addition, astrocytes likely play a role in the modulation of TRPV1-expressing neurons. In summary, this study identified specific hypothalamic regions where TRPV1 is expressed and functional in adult mice and the existence of direct connections between TRPV1Cre/tdTom neurons. NEW & NOTEWORTHY Transient receptor potential vanilloid type 1 (TRPV1) is expressed in the hypothalamus, and TRPV1-dependent regulation of preautonomic neurons is decreased in hyperglycemic conditions. Our study demonstrated functional expression of TRPV1 in two hypothalamic nuclei involved in the control of energy homeostasis. Our results also revealed that a subset of TRPV1-expressing neurons receive TRPV1-expressing excitatory inputs. These findings suggest direct interaction between TRPV1-expressing neurons.
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Affiliation(s)
- Adrien J R Molinas
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Lucie D Desmoulins
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Brooke V Hamling
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
- Neuroscience Program, Brain Institute, Tulane University , New Orleans, Louisiana
| | - Sierra M Butcher
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
- Neuroscience Program, Brain Institute, Tulane University , New Orleans, Louisiana
| | - Imran J Anwar
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Kayoko Miyata
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Courtney L Enix
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Courtney M Dugas
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Ryousuke Satou
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
| | - Andrei V Derbenev
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
- Neuroscience Program, Brain Institute, Tulane University , New Orleans, Louisiana
| | - Andrea Zsombok
- Department of Physiology, School of Medicine, Tulane University , New Orleans, Louisiana
- Neuroscience Program, Brain Institute, Tulane University , New Orleans, Louisiana
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Navarro G, Allard C, Morford JJ, Xu W, Liu S, Molinas AJ, Butcher SM, Fine NH, Blandino-Rosano M, Sure VN, Yu S, Zhang R, Münzberg H, Jacobson DA, Katakam PV, Hodson DJ, Bernal-Mizrachi E, Zsombok A, Mauvais-Jarvis F. Androgen excess in pancreatic β cells and neurons predisposes female mice to type 2 diabetes. JCI Insight 2018; 3:98607. [PMID: 29925687 PMCID: PMC6124401 DOI: 10.1172/jci.insight.98607] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/10/2018] [Indexed: 11/17/2022] Open
Abstract
Androgen excess predisposes women to type 2 diabetes (T2D), but the mechanism of this is poorly understood. We report that female mice fed a Western diet and exposed to chronic androgen excess using dihydrotestosterone (DHT) exhibit hyperinsulinemia and insulin resistance associated with secondary pancreatic β cell failure, leading to hyperglycemia. These abnormalities are not observed in mice lacking the androgen receptor (AR) in β cells and partially in neurons of the mediobasal hypothalamus (MBH) as well as in mice lacking AR selectively in neurons. Accordingly, i.c.v. infusion of DHT produces hyperinsulinemia and insulin resistance in female WT mice. We observe that acute DHT produces insulin hypersecretion in response to glucose in cultured female mouse and human pancreatic islets in an AR-dependent manner via a cAMP- and mTOR-dependent pathway. Acute DHT exposure increases mitochondrial respiration and oxygen consumption in female cultured islets. As a result, chronic DHT exposure in vivo promotes islet oxidative damage and susceptibility to additional stress induced by streptozotocin via AR in β cells. This study suggests that excess androgen predisposes female mice to T2D following AR activation in neurons, producing peripheral insulin resistance, and in pancreatic β cells, promoting insulin hypersecretion, oxidative injury, and secondary β cell failure.
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Affiliation(s)
- Guadalupe Navarro
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Camille Allard
- Department of Medicine, Section of Endocrinology and Metabolism, and
| | - Jamie J. Morford
- Department of Medicine, Section of Endocrinology and Metabolism, and
| | - Weiwei Xu
- Department of Medicine, Section of Endocrinology and Metabolism, and
| | - Suhuan Liu
- Department of Medicine, Division of Endocrinology, Metabolism and Molecular Medicine, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
| | - Adrien J.R. Molinas
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
| | - Sierra M. Butcher
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
| | - Nicholas H.F. Fine
- Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, United Kingdom
- Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, United Kingdom
| | - Manuel Blandino-Rosano
- Department of Internal Medicine, Division Endocrinology, Metabolism and Diabetes, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Venkata N. Sure
- Department of Pharmacology, Tulane University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
| | - Sangho Yu
- Department of Neurobiology of Nutrition and Metabolism, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Rui Zhang
- Department of Neurobiology of Nutrition and Metabolism, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - Heike Münzberg
- Department of Neurobiology of Nutrition and Metabolism, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana, USA
| | - David A. Jacobson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Prasad V. Katakam
- Department of Pharmacology, Tulane University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
| | - David J. Hodson
- Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, United Kingdom
- Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, United Kingdom
| | - Ernesto Bernal-Mizrachi
- Department of Internal Medicine, Division Endocrinology, Metabolism and Diabetes, Miller School of Medicine, University of Miami, Miami, Florida, USA
| | - Andrea Zsombok
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
| | - Franck Mauvais-Jarvis
- Department of Medicine, Section of Endocrinology and Metabolism, and
- Department of Physiology, Tulane University Health Sciences Center, School of Medicine, New Orleans, Louisiana, USA
- Tulane Brain Institute and
- Southeast Louisiana Veterans Healthcare System, New Orleans, Louisiana, USA
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Hunter DA, Yoo SD, Butcher SM, McManus MT. Expression of 1-aminocyclopropane-1-carboxylate oxidase during leaf ontogeny in white clover. Plant Physiol 1999; 120:131-42. [PMID: 10318691 PMCID: PMC59245 DOI: 10.1104/pp.120.1.131] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/1998] [Accepted: 12/23/1998] [Indexed: 05/18/2023]
Abstract
We examined the expression of three distinct 1-aminocyclopropane-1-carboxylic acid oxidase genes during leaf ontogeny in white clover (Trifolium repens). Significant production of ethylene occurs at the apex, in newly initiated leaves, and in senescent leaf tissue. We used a combination of reverse transcriptase-polymerase chain reaction and 3'-rapid amplification of cDNA ends to identify three distinct DNA sequences designated TRACO1, TRACO2, and TRACO3, each with homology to 1-aminocyclopropane-1-carboxylic acid oxidase. Southern analysis confirmed that these sequences represent three distinct genes. Northern analysis revealed that TRACO1 is expressed specifically in the apex and TRACO2 is expressed in the apex and in developing and mature green leaves, with maximum expression in developing leaf tissue. The third gene, TRACO3, is expressed in senescent leaf tissue. Antibodies were raised to each gene product expressed in Escherichia coli, and western analysis showed that the TRACO1 antibody recognizes a protein of approximately 205 kD (as determined by gradient sodium dodecyl sulfate-polyacylamide gel electrophoresis) that is expressed preferentially in apical tissue. The TRACO2 antibody recognizes a protein of approximately 36.4 kD (as determined by gradient sodium dodecyl sulfate-polyacylamide gel electrophoresis) that is expressed in the apex and in developing and mature green leaves, with maximum expression in mature green tissue. No protein recognition by the TRACO3 antibody could be detected in senescent tissue or at any other stage of leaf development.
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Affiliation(s)
- D A Hunter
- Institute of Molecular BioSciences, Massey University, Private Bag 11222, Palmerston North, New Zealand
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