1
|
Hymer WC, Kraemer WJ. Resistance exercise stress: theoretical mechanisms for growth hormone processing and release from the anterior pituitary somatotroph. Eur J Appl Physiol 2023; 123:1867-1878. [PMID: 37421488 DOI: 10.1007/s00421-023-05263-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 06/15/2023] [Indexed: 07/10/2023]
Abstract
Heavy resistance exercise (HRE) is the most effective method for inducing muscular hypertrophy and stimulating anabolic hormones, including growth hormone, into the blood. In this review, we explore possible mechanisms within the GH secretory pathway of the pituitary somatotroph, which are likely to modulate the flow of hormone synthesis and packaging as it is processed prior to exocytosis. Special emphasis is placed on the secretory granule and its possible role as a signaling hub. We also review data that summarize how HRE affects the quality and quantity of the secreted hormone. Finally, these pathway mechanisms are considered in the context of heterogeneity of the somatotroph population in the anterior pituitary.
Collapse
Affiliation(s)
- Wesley C Hymer
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - William J Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, OH, 43802, USA.
- Department of Kinesiology, University of Connecticut, Storrs, CT, USA.
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, CT, USA.
- School of Medical and Health Sciences, Edith Cowan University, Perth, Australia.
| |
Collapse
|
2
|
Kraemer WJ, Caldwell LK, Post EM, Beeler MK, Dickerson RM, Kennett MJ, Volek JS, Maresh CM, Hymer WC. Recovery using "float" from high intensity stress on growth hormone-like molecules in resistance trained men. Growth Horm IGF Res 2020; 55:101355. [PMID: 33032163 DOI: 10.1016/j.ghir.2020.101355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 08/27/2020] [Accepted: 08/30/2020] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The purpose of this study was to examine the influence of a novel "floatation-restricted environmental stimulation therapy" (floatation-REST) on growth hormone responses to an intense resistance exercise stress. DESIGN Nine resistance trained men (age: 23.4 ± 2.5 yrs.; height: 175.3 ± 5.4 cm; body mass: 85.3 ± 7.9 kg) completed a balanced, crossover-controlled study design with two identical exercise trials, differing only in post-exercise recovery intervention (i.e., control or floatation-REST). A two-week washout period was used between experimental conditions. Plasma lactate was measured pre-exercise, immediately post-exercise and after the 1 h. recovery interventions. Plasma iGH was measured pre-exercise, immediately-post exercise, and after the recovery intervention, as well as 24 h and 48 h after the exercise test. The bGH-L was measured only at pre-exercise and following each recovery intervention. RESULTS For both experimental conditions, a significant (P ≤ 0.05) increase in lactate concentrations were observed immediately post-exercise (~14 mmol • L-1) and remained slightly elevated after the recovery condition. The same pattern of responses was observed for iGH with no differences from resting values at 24 and 48 h of recovery. The bGH-L showed no exercise-induced changes following recovery with either treatment condition, however concentration values were dramatically lower than ever reported. CONCLUSION The use of floatation-REST therapy immediately following intense resistance exercise does not appear to influence anterior pituitary function in highly resistance trained men. However, the lower values of bGH suggest dramatically different molecular processing mechanisms at work in this highly trained population.
Collapse
Affiliation(s)
- William J Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America.
| | - Lydia K Caldwell
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America
| | - Emily M Post
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America
| | - Matthew K Beeler
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America
| | - Ryan M Dickerson
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America
| | - Mary J Kennett
- Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802, United States of America
| | - Jeff S Volek
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America
| | - Carl M Maresh
- Department of Human Sciences, The Ohio State University, Columbus, OH 43210, United States of America
| | - Wesley C Hymer
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, United States of America
| |
Collapse
|
3
|
Ariyasu D, Kubo E, Higa D, Shibata S, Takaoka Y, Sugimoto M, Imaizumi K, Hasegawa T, Araki K. Decreased Activity of the Ghrhr and Gh Promoters Causes Dominantly Inherited GH Deficiency in Humanized GH1 Mouse Models. Endocrinology 2019; 160:2673-2691. [PMID: 31436800 DOI: 10.1210/en.2019-00306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 08/15/2019] [Indexed: 02/06/2023]
Abstract
Isolated growth hormone deficiency type II (IGHD2) is mainly caused by heterozygous splice-site mutations in intron 3 of the GH1 gene. A dominant-negative effect of the mutant GH lacking exon 3 on wild-type GH secretion has been proposed; however, the molecular mechanisms involved are elusive. To uncover the molecular systems underlying GH deficiency in IGHD2, we established IGHD2 model mice, which carry both wild-type and mutant copies of the human GH1 gene, replacing each of the endogenous mouse Gh loci. Our IGHD2 model mice exhibited growth retardation along with intact cellular architecture and mildly activated endoplasmic reticulum stress in the pituitary gland, caused by decreased GH-releasing hormone receptor (Ghrhr) and Gh gene promoter activities. Decreased Ghrhr and Gh promoter activities were likely caused by reduced levels of nuclear CREB3L2, which was demonstrated to stimulate Ghrhr and Gh promoter activity. To our knowledge, this is the first in vivo study to reveal a novel molecular mechanism of GH deficiency in IGHD2, representing a new paradigm that differs from widely accepted models.
Collapse
Affiliation(s)
- Daisuke Ariyasu
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
- Graduate School of Medicine, Keio University, Tokyo, Japan
| | - Emika Kubo
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Daisuke Higa
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Shinsuke Shibata
- Electron Microscope Laboratory, Keio University School of Medicine, Tokyo, Japan
| | - Yutaka Takaoka
- Division of Medical Informatics and Bioinformatics, Kobe University Hospital, Hyogo, Japan
| | - Michihiko Sugimoto
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan
| | | | - Kimi Araki
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto, Japan
- Center for Metabolic Regulation of Healthy Aging, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| |
Collapse
|
4
|
Ariyasu D, Yoshida H, Hasegawa Y. Endoplasmic Reticulum (ER) Stress and Endocrine Disorders. Int J Mol Sci 2017; 18:ijms18020382. [PMID: 28208663 PMCID: PMC5343917 DOI: 10.3390/ijms18020382] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 01/24/2017] [Accepted: 02/03/2017] [Indexed: 12/15/2022] Open
Abstract
The endoplasmic reticulum (ER) is the organelle where secretory and membrane proteins are synthesized and folded. Unfolded proteins that are retained within the ER can cause ER stress. Eukaryotic cells have a defense system called the “unfolded protein response” (UPR), which protects cells from ER stress. Cells undergo apoptosis when ER stress exceeds the capacity of the UPR, which has been revealed to cause human diseases. Although neurodegenerative diseases are well-known ER stress-related diseases, it has been discovered that endocrine diseases are also related to ER stress. In this review, we focus on ER stress-related human endocrine disorders. In addition to diabetes mellitus, which is well characterized, several relatively rare genetic disorders such as familial neurohypophyseal diabetes insipidus (FNDI), Wolfram syndrome, and isolated growth hormone deficiency type II (IGHD2) are discussed in this article.
Collapse
Affiliation(s)
- Daisuke Ariyasu
- Division of Developmental Genetics, Institute of Resource Development and Analysis, Kumamoto University, Kumamoto 860-0811, Japan.
| | - Hiderou Yoshida
- Department of Biochemistry and Molecular Biology, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan.
| | - Yukihiro Hasegawa
- Division of Endocrinology and Metabolism, Tokyo Metropolitan Children's Medical Center, Tokyo 183-8561, Japan.
| |
Collapse
|
5
|
Ariyasu D, Yoshida H, Yamada M, Hasegawa Y. Endoplasmic reticulum stress and apoptosis contribute to the pathogenesis of dominantly inherited isolated GH deficiency due to GH1 gene splice site mutations. Endocrinology 2013; 154:3228-39. [PMID: 23736291 DOI: 10.1210/en.2013-1249] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Dominantly inherited isolated GH deficiency is mainly caused by a heterozygous donor site mutation of intron 3 in the GH1 gene. An exon 3 deletion in GH (del32-71 GH) is produced from a mutant allele, whereas wild-type GH is produced from the other allele. Several studies have demonstrated a dominant negative effect of del32-71 GH on wild-type GH secretion, but the precise molecular mechanisms remain unclear. We hypothesized that unfolded del32-71 GH accumulates in the endoplasmic reticulum (ER) and causes ER stress and apoptosis in somatotrophs, promoting GH deficiency. To evaluate del32-71 GH-mediated ER stress, we established GH4C1 cell lines with doxycycline (dox)-controlled del32-71 GH expression. In 20 of 23 dox-controlled cell lines, the concentration of wild-type GH in the culture medium significantly decreased with del32-71 GH induction, demonstrating the dominant negative effect of this mutant. Cell viability, mRNA abundance of ER stress-response genes, caspase activation, and DNA fragmentation were evaluated in 5 dox-controlled cell lines selected as cellular models. In 4 of the 5 cell lines, del32-71 GH induction decreased cell viability, increased expression of 3 major ER stress response pathways (PRKR-like endoplasmic reticulum kinase [PERK], activating transcription factor-6 [ATF6], and inositol requirement 1 [IRE1]), and induced caspase-3 and caspase-7 activation. In 1 of the 4 cell lines, DNA fragmentation was demonstrated. Finally, overexpression of XBP1(S), a nuclear transcription factor downstream of IRE1, completely reversed the observed caspase activation. These data suggested that del32-71 GH-mediated ER stress and apoptosis contributed to the decrease in wild-type GH secretion observed in GH deficiency due to the GH1 gene slice-site mutations.
Collapse
Affiliation(s)
- Daisuke Ariyasu
- Department of Endocrinology and Metabolism, Tokyo Metropolitan Children’s Medical Center, Tokyo 183–8561, Japan
| | | | | | | |
Collapse
|
6
|
Wei C, Thatcher EJ, Olena AF, Cha DJ, Perdigoto AL, Marshall AF, Carter BD, Broadie K, Patton JG. miR-153 regulates SNAP-25, synaptic transmission, and neuronal development. PLoS One 2013; 8:e57080. [PMID: 23451149 PMCID: PMC3581580 DOI: 10.1371/journal.pone.0057080] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 01/16/2013] [Indexed: 01/01/2023] Open
Abstract
SNAP-25 is a core component of the trimeric SNARE complex mediating vesicle exocytosis during membrane addition for neuronal growth, neuropeptide/growth factor secretion, and neurotransmitter release during synaptic transmission. Here, we report a novel microRNA mechanism of SNAP-25 regulation controlling motor neuron development, neurosecretion, synaptic activity, and movement in zebrafish. Loss of miR-153 causes overexpression of SNAP-25 and consequent hyperactive movement in early zebrafish embryos. Conversely, overexpression of miR-153 causes SNAP-25 down regulation resulting in near complete paralysis, mimicking the effects of treatment with Botulinum neurotoxin. miR-153-dependent changes in synaptic activity at the neuromuscular junction are consistent with the observed movement defects. Underlying the movement defects, perturbation of miR-153 function causes dramatic developmental changes in motor neuron patterning and branching. Together, our results indicate that precise control of SNAP-25 expression by miR-153 is critically important for proper neuronal patterning as well as neurotransmission.
Collapse
Affiliation(s)
- Chunyao Wei
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Elizabeth J. Thatcher
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Abigail F. Olena
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Diana J. Cha
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Ana L. Perdigoto
- Department of Biochemistry, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Andrew F. Marshall
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Bruce D. Carter
- Department of Biochemistry, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - Kendal Broadie
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
| | - James G. Patton
- Department of Biological Sciences, Vanderbilt University and Medical School, Nashville, Tennessee, United States of America
- * E-mail:
| |
Collapse
|
7
|
Lochmatter D, Strom M, Eblé A, Petkovic V, Flück CE, Bidlingmaier M, Robinson IC, Mullis PE. Isolated GH deficiency type II: knockdown of the harmful Delta3GH recovers wt-GH secretion in rat tumor pituitary cells. Endocrinology 2010; 151:4400-9. [PMID: 20591972 DOI: 10.1210/en.2010-0196] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Isolated GH deficiency type II (IGHD II) is the autosomal dominant form of GHD. In the majority of the cases, this disorder is due to specific GH-1 gene mutations that lead to mRNA missplicing and subsequent loss of exon 3 sequences. When misspliced RNA is translated, it produces a toxic 17.5-kDa GH (Delta3GH) isoform that reduces the accumulation and secretion of wild-type-GH. At present, patients suffering from this type of disease are treated with daily injections of recombinant human GH in order to maintain normal growth. However, this type of replacement therapy does not prevent toxic effects of the Delta3GH mutant on the pituitary gland, which can eventually lead to other hormonal deficiencies. We developed a strategy involving Delta3GH isoform knockdown mediated by expression of a microRNA-30-adapted short hairpin RNA (shRNA) specifically targeting the Delta3GH mRNA of human (shRNAmir-Delta3). Rat pituitary tumor GC cells expressing Delta3GH upon doxycycline induction were transduced with shRNAmir-Delta3 lentiviral vectors, which significantly reduced Delta3GH protein levels and improved human wild-type-GH secretion in comparison with a shRNAmir targeting a scrambled sequence. No toxicity due to shRNAmir expression could be observed in cell proliferation assays. Confocal microscopy strongly suggested that shRNAmir-Delta3 enabled the recovery of GH granule storage and secretory capacity. These viral vectors have shown their ability to stably integrate, express shRNAmir, and rescue IGHD II phenotype in rat pituitary tumor GC cells, a methodology that opens new perspectives for the development of gene therapy to treat IGHD patients.
Collapse
Affiliation(s)
- Didier Lochmatter
- Pediatric Endocrinology, University Children's Hospital, Inselspital, CH-3010 Bern, Switzerland
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Alatzoglou KS, Turton JP, Kelberman D, Clayton PE, Mehta A, Buchanan C, Aylwin S, Crowne EC, Christesen HT, Hertel NT, Trainer PJ, Savage MO, Raza J, Banerjee K, Sinha SK, Ten S, Mushtaq T, Brauner R, Cheetham TD, Hindmarsh PC, Mullis PE, Dattani MT. Expanding the spectrum of mutations in GH1 and GHRHR: genetic screening in a large cohort of patients with congenital isolated growth hormone deficiency. J Clin Endocrinol Metab 2009; 94:3191-9. [PMID: 19567534 DOI: 10.1210/jc.2008-2783] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
CONTEXT It is estimated that 3-30% of cases with isolated GH deficiency (IGHD) have a genetic etiology, with a number of mutations being reported in GH1 and GHRHR. The aim of our study was to genetically characterize a cohort of patients with congenital IGHD and analyze their characteristics. PATIENTS AND METHODS A total of 224 patients (190 pedigrees) with IGHD and a eutopic posterior pituitary were screened for mutations in GH1 and GHRHR. To explore the possibility of an association of GH1 abnormalities with multiple pituitary hormone deficiencies, we have screened 62 patients with either multiple pituitary hormone deficiencies (42 pedigrees), or IGHD with an ectopic posterior pituitary (21 pedigrees). RESULTS Mutations in GH1 and GHRHR were identified in 41 patients from 21 pedigrees (11.1%), with a higher prevalence in familial cases (38.6%). These included previously described and novel mutations in GH1 (C182X, G120V, R178H, IVS3+4nt, a>t) and GHRHR (W273S, R94L, R162W). Autosomal dominant, type II IGHD was the commonest form (52.4%), followed by type IB (42.8%) and type IA (4.8%). Patients with type II IGHD had highly variable phenotypes. There was no difference in the endocrinology or magnetic resonance imaging appearance between patients with and without mutations, although those with mutations presented with more significant growth failure (height, -4.7 +/- 1.6 SDS vs. -3.4 +/- 1.7 SDS) (P = 0.001). There was no apparent difference between patients with mutations in GH1 and GHRHR. CONCLUSIONS IGHD patients with severe growth failure and a positive family history should be screened for genetic mutations; the evolving endocrinopathy observed in some of these patients suggests the need for long-term follow-up.
Collapse
Affiliation(s)
- Kyriaki S Alatzoglou
- Developmental Endocrinology Research Group, Clinical and Molecular Genetics Unit, University College London Institute of Child Health, London WC1N 1EH, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|