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Pierce JR, Martin BJ, Rarick KR, Alemany JA, Staab JS, Kraemer WJ, Hymer WC, Nindl BC. Growth Hormone and Insulin-like Growth Factor-I Molecular Weight Isoform Responses to Resistance Exercise Are Sex-Dependent. Front Endocrinol (Lausanne) 2020; 11:571. [PMID: 32973684 PMCID: PMC7472848 DOI: 10.3389/fendo.2020.00571] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 07/13/2020] [Indexed: 11/25/2022] Open
Abstract
Purpose: To determine if acute resistance exercise-induced increases in growth hormone (GH) and insulin-like growth factor-I (IGF-I) were differentially responsive for one or more molecular weight (MW) isoforms and if these responses were sex-dependent. Methods: College-aged men (n = 10) and women (n = 10) performed an acute resistance exercise test (ARET; 6 sets, 10 repetition maximum (10-RM) squat, 2-min inter-set rest). Serum aliquots from blood drawn Pre-, Mid-, and Post-ARET (0, +15, and +30-min post) were processed using High Performance Liquid Chromatography (HPLC) fractionation and pooled into 3 MW fractions (Fr.A: >60; Fr.B: 30-60; Fr.C: <30 kDa). Results: We observed a hierarchy of serum protein collected among GH fractions across all time points independent of sex (Fr.C > Fr.A > Fr.B, p ≤ 0.03). Sex × time interactions indicated that women experienced earlier and augmented increases in all serum GH MW isoform fraction pools (p < 0.05); however, men demonstrated delayed and sustained GH elevations (p < 0.01) in all fractions through +30-min of recovery. Similarly, we observed a sex-independent hierarchy among IGF-I MW fraction pools (Fr.A > Fr.B > Fr.C, p ≤ 0.01). Furthermore, we observed increases in IGF-I Fr. A (ternary complexes) in men only (p ≤ 0.05), and increases in Fr.C (free/unbound IGF-I) in women only (p ≤ 0.05) vs. baseline, respectively. Conclusions: These data indicate that the processing of GH and IGF-I isoforms from the somatotrophs and hepatocytes are differential in their response to strenuous resistance exercise and reflect both temporal and sex-related differences.
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Affiliation(s)
- Joseph R. Pierce
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, United States
- *Correspondence: Joseph R. Pierce
| | - Brian J. Martin
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
| | - Kevin R. Rarick
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, United States
| | - Joseph A. Alemany
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, United States
| | - Jeffery S. Staab
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, United States
| | - William J. Kraemer
- Department of Kinesiology, University of Connecticut, Mansfield, CT, United States
| | - Wesley C. Hymer
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
| | - Bradley C. Nindl
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, United States
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
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Nindl BC, Eagle SR, Matheny RW, Martin BJ, Rarick KR, Pierce JR, Sharp MA, Kellogg MD, Patton JF. Characterization of growth hormone disulfide-linked molecular isoforms during post-exercise release vs nocturnal pulsatile release reveals similar milieu composition. Growth Horm IGF Res 2018; 42-43:102-107. [PMID: 30399477 DOI: 10.1016/j.ghir.2018.10.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/10/2018] [Accepted: 10/18/2018] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To characterize the influence of mode (aerobic/resistance) and volume of exercise (moderate/high) on circulating GH immediately post-exercise as well as following the onset of sleep. DESIGN This study used repeated measures in which subjects randomly completed 5 separate conditions: control (no exercise), moderate volume resistance exercise (MR), high-volume resistance exercise (HR), moderate volume aerobic exercise (MA), and high volume aerobic exercise (HA). METHODS Subjects had two overnight stays on each of the 5 iterations. Serial blood draws began as soon as possible after the completion of the exercise session. Blood was obtained every 20 min for 24-h. GH was measured using a chemiluminescent immunoassay. Pooled samples representing post exercise (PE) and first nocturnal pulse (NP) were divided into two aliquots. One of these aliquots was chemically reduced by adding 10 mM glutathione (GSH) to break down disulfide-linked aggregates. RESULTS No differences were observed when pooling GH response at post-exercise (2.02 ± 0.21) and nocturnal pulse (2.63 ± 0.51; p = .32). Pairwise comparisons revealed main effect differences between controls (1.19 ± 0.29) and both MA (2.86 ± 0.31; p = .009) and HA (3.73 ± 0.71; p = .001). Both MA (p = .049) and HA (p = .035) responses were significantly larger than the MR stimulus (1.96 ± 0.28). With GSH reduction, controls significantly differed from MA (p = .018) and HA (p = .003) during PE, but only differed from HA (p = .003) during NP. CONCLUSIONS This study demonstrated similar GH responses to exercise and nocturnal pulse, indicating that mode and intensity of exercise does not proportionately affect GH dimeric isoform concentration.
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Affiliation(s)
- Bradley C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA 15203, United States.
| | - Shawn R Eagle
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA 15203, United States
| | - Ronald W Matheny
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States
| | - Brian J Martin
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA 15203, United States
| | - Kevin R Rarick
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States
| | - Joseph R Pierce
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States
| | - Marilyn A Sharp
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States
| | - Mark D Kellogg
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States
| | - John F Patton
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA 01760, United States
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Ribeiro de Oliveira Longo Schweizer J, Ribeiro-Oliveira A, Bidlingmaier M. Growth hormone: isoforms, clinical aspects and assays interference. Clin Diabetes Endocrinol 2018; 4:18. [PMID: 30181896 PMCID: PMC6114276 DOI: 10.1186/s40842-018-0068-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/19/2018] [Indexed: 11/11/2022] Open
Abstract
The measurement of circulating concentrations of growth hormone (GH) is an indispensable tool in the diagnosis of both GH deficiency and GH excess. GH is a heterogeneous protein composed of several molecular isoforms, but the physiological role of these different isoforms has not yet been fully understood. The 22KD GH (22 K-GH) is the main isoform in circulation, followed by 20KD GH (20 K-GH) and other rare isoforms. Studies have been performed to better understand the biological actions of the different isoforms as well as their importance in pathological conditions. Generally, the non-22 K- and 20 K-GH isoforms are secreted in parallel to 22 K-GH, and only very moderate changes in the ratio between isoforms have been described in some pituitary tumors or during exercise. Therefore, in a diagnostic approach, concentrations of 22 K-GH accurately reflect total GH secretion. On the other hand, the differential recognition of GH isoforms by different GH immunoassays used in clinical routine contributes to the known discrepancy in results from different GH assays. This makes the application of uniform decision limits problematic. Therefore, the worldwide efforts to standardize GH assays include the recommendation to use 22 K-GH specific GH assays calibrated against the pure 22 K-GH reference preparation 98/574. Adoption of this recommendation might lead to improvement in diagnosis and follow-up of pathological conditions, and facilitate the comparison of results from different laboratories.
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Affiliation(s)
| | - Antônio Ribeiro-Oliveira
- 1Endocrinology Laboratory of Federal University of Minas Gerais. Alfredo Balena, 190, Santa Efigênia, Belo Horizonte, 30130-100 Brazil
| | - Martin Bidlingmaier
- 2Endocrine Laboratory, Medizinische Klinik und Poliklinik IV, Klinikum der Universität München, Ziemssenstraße 1, 80336 Munich, Germany
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Nindl BC, Alemany JA, Rarick KR, Eagle SR, Darnell ME, Allison KF, Harman EA. Differential basal and exercise-induced IGF-I system responses to resistance vs. calisthenic-based military readiness training programs. Growth Horm IGF Res 2017; 32:33-40. [PMID: 27979730 DOI: 10.1016/j.ghir.2016.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 11/22/2016] [Accepted: 12/02/2016] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The purpose of this study was to: 1) evaluate differential responses of the IGF-I system to either a calisthenic- or resistance exercise-based program and 2) determine if this chronic training altered the IGF-I system during an acute resistance exercise protocol. DESIGN Thirty-two volunteers were randomly assigned into a resistance exercise-based training (RT) group (n=15, 27±5y, 174±6cm, 81±12kg) or a calisthenic-based training group (CT) (n=17, 29±5y, 179±8cm, 85±10kg) and all underwent 8weeks of exercise training (1.5h/d, 5d/wk). Basal blood was sampled pre- (Week 0), mid- (Week 4) and post-training (Week 8) and assayed for IGF-I system analytes. An acute resistance exercise protocol (AREP) was conducted preand post-training consisting of 6 sets of 10 repetitions in the squat with two minutes of rest in between sets and the IGF-I system analytes measured. A repeated measures ANOVA (p≤0.05) was used for statistical analysis. RESULTS No interaction or within-subject effects were observed for basal total IGF-I, free IGF-I, or IGFBP-1. IGFBP-2 (pre; 578.6±295.7<mid; 828.6±104.2=post; 833.7±481.2ng/mL; p=0.008) and Acid Labile Subunit (ALS) changed over the exercise training (pre-; 16.2±1.3=mid-; 17.6±1.8>post-training; 14.3±1.9μg/mL; p=0.01). An interaction was observed for the RT group as IGFBP-3 increased from pre to mid (3462.4±216.4 vs. 3962.2±227.9ng/mL), but was not significant at the post-training time point (3770.3±228.7ng/mL). AREP caused all analytes except free IGF-I (40% decrease) to increase (17-27%; p=0.001) during exercise, returning to baseline concentration into recovery. CONCLUSION Post-training, bioavailable IGF-I recovered more rapidly post-exercise. 8wks of chronic physical training resulted in increased basal IGFBP-2 and IGFBP-3, decreased ALS, increased pre-AREP free IGF-I and a more rapid free IGF-I recovery post-AREP. While total IGF-I was insensitive to chronic physical training, changes were observed with circulating IGFBPs and bioavailable IGF-I. To glean the most robust information on the effects of exercise training, studies must move beyond relying solely on total IGF-I measures and should consider IGFBPs and bioavailable IGF-I as these components of the circulating IGF-I system are essential determinants of IGF-I physiological action.
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Affiliation(s)
- Bradley C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15203, United States; Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 17063, United States
| | - Joseph A Alemany
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 17063, United States; Injury Prevention Program, Epidemiology and Disease Surveillance, U.S. Army Public Health Center (Provisional), Aberdeen Proving Ground, MD 21010, United States
| | - Kevin R Rarick
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 17063, United States
| | - Shawn R Eagle
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15203, United States.
| | - Mathew E Darnell
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15203, United States
| | - Katelyn F Allison
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15203, United States
| | - Everett A Harman
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 17063, United States
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Nindl BC, Pierce JR, Rarick KR, Tuckow AP, Alemany JA, Sharp MA, Kellogg MD, Patton JF. Twenty-hour growth hormone secretory profiles after aerobic and resistance exercise. Med Sci Sports Exerc 2015; 46:1917-27. [PMID: 24576855 DOI: 10.1249/mss.0000000000000315] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION The pulsatile secretion pattern of growth hormone (GH) is an important parameter of GH action at peripheral tissues, and more information is needed on how exercise impacts GH secretion. This study hypothesized that both aerobic and resistance exercise would exhibit dose-response relationships with respect to exercise duration and 20-h postexercise GH secretion. METHODS Eight healthy men randomly completed five separate conditions: 1) control (no exercise; CON), 2) a moderate-duration (1-h) aerobic exercise session (MA), 3) a long-duration (2-h) aerobic exercise session (LA), 4) a moderate-duration (1-h) resistance exercise session (MR), and 5) a long-duration (2-h) resistance exercise session (LR). Exercise intensity, diet, sleep, and physical activity were strictly controlled during each condition, and blood was sampled postexercise every 20 min for 20 h, and GH secretion parameters were analyzed via cluster and deconvolution analyses. RESULTS Only the 2-h aerobic exercise bout resulted in a significant amplification of GH secretion as evidenced by increases in GH burst peak amplitude (∼100%), basal GH secretion rate (∼127%), total GH basal secretion (∼120%), total pulsatile secretion (∼88%), and total GH secretion (∼89%) over the control (i.e., no exercise) condition. GH secretions for the resistance exercise conditions were not different from control. CONCLUSIONS The fact that the 2-h aerobic exercise condition resulted in higher energy expenditure than the other exercise conditions could offer a partial explanation for the greater GH amplification because of the metabolic effects that GH exerts in stimulating postexercise lipolysis. We conclude that extending the duration of aerobic exercise, but not resistance exercise, from 1- to 2-h significantly amplifies GH secretion during a 20-h period.
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Affiliation(s)
- Bradley C Nindl
- 1Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA; and 2Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA
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Luk HY, Kraemer WJ, Szivak TK, Flanagan SD, Hooper DR, Kupchak BR, Comstock BA, Dunn-Lewis C, Vingren JL, DuPont WH, Hymer WC. Acute resistance exercise stimulates sex-specific dimeric immunoreactive growth hormone responses. Growth Horm IGF Res 2015; 25:136-140. [PMID: 25934139 DOI: 10.1016/j.ghir.2015.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/30/2015] [Accepted: 02/13/2015] [Indexed: 10/24/2022]
Abstract
PURPOSE We sought to determine if an acute heavy resistance exercise test (AHRET) would elicit sex-specific responses in circulating growth hormone (GH), with untreated serum and serum treated with a reducing agent to break disulfide-bindings between GH dimers. METHODS 19 untrained participants (nine men and ten women) participated in an acute heavy resistance exercise test using the back squat. Blood samples were drawn before exercise (Pre), immediate post (IP), +15 min (+15), and +30 min (+30) afterwards. Serum samples were chemically reduced using glutathione (GSH). ELISAs were then used to compare immunoreactive GH concentrations in reduced (+GSH) and non-reduced (-GSH) samples. Data were analyzed using a three-way (2 sex × 2 treatment × 4 time) mixed methods ANOVA, with significance set at p ≤ 0.05. RESULTS GSH reduction resulted in increased immunoreactive GH concentrations when compared to non-reduced samples at Pre (1.68 ± 0.33 μg/L vs 1.25 ± 0.25 μg/L), IP (7.69 ± 1.08 μg/L vs 5.76 ± 0.80 μg/L), +15 min (4.39 ± 0.58 μg/L vs 3.24 ± 0.43 μg/L), and +30 min (2.35 ± 0.49 μg/L vs 1.45 ± 0.23 μg/L). Also, women demonstrated greater GH responses compared to men, and this was not affected by reduction. CONCLUSIONS Heavy resistance exercise increases immunoreactive GH dimer concentrations in men and women, with larger increases in women and more sustained response in men. The physiological significance of a sexually dimorphic GH response adds to the growing literature on aggregate GH and may be explained by differences in sex hormones and the structure of the GH cell network.
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Affiliation(s)
- Hui Ying Luk
- Department of Kinesiology, Health Promotion and Recreation, University of North Texas, Denton, TX, USA
| | - William J Kraemer
- Department of Human Sciences, The Ohio State University, Columbus, OH, USA.
| | - Tunde K Szivak
- Department of Human Sciences, The Ohio State University, Columbus, OH, USA
| | - Shawn D Flanagan
- Department of Human Sciences, The Ohio State University, Columbus, OH, USA
| | - David R Hooper
- Department of Human Sciences, The Ohio State University, Columbus, OH, USA
| | - Brian R Kupchak
- Human Performance Laboratory, Department of Kinesiology, University of Connecticut, Storrs, CT, USA
| | - Brett A Comstock
- Division of Kinesiology and Sport Science, University of South Dakota, Vermillion, SD, USA
| | - Courtenay Dunn-Lewis
- Department of Health Sciences, School of Science and Engineering, Merrimack College, North Andover, MA, USA
| | - Jakob L Vingren
- Department of Kinesiology, Health Promotion and Recreation, University of North Texas, Denton, TX, USA
| | - William H DuPont
- Department of Human Sciences, The Ohio State University, Columbus, OH, USA
| | - Wesley C Hymer
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, USA
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Adams GR, Bamman MM. Characterization and regulation of mechanical loading-induced compensatory muscle hypertrophy. Compr Physiol 2013; 2:2829-70. [PMID: 23720267 DOI: 10.1002/cphy.c110066] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In mammalian systems, skeletal muscle exists in a dynamic state that monitors and regulates the physiological investment in muscle size to meet the current level of functional demand. This review attempts to consolidate current knowledge concerning development of the compensatory hypertrophy that occurs in response to a sustained increase in the mechanical loading of skeletal muscle. Topics covered include: defining and measuring compensatory hypertrophy, experimental models, loading stimulus parameters, acute responses to increased loading, hyperplasia, myofiber-type adaptations, the involvement of satellite cells, mRNA translational control, mechanotransduction, and endocrinology. The authors conclude with their impressions of current knowledge gaps in the field that are ripe for future study.
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Affiliation(s)
- Gregory R Adams
- Department of Physiology and Biophysics, University of California Irvine, Irvine, California, USA.
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Scott JM, Koelwyn GJ, Hornsby WE, Khouri M, Peppercorn J, Douglas PS, Jones LW. Exercise Therapy as Treatment for Cardiovascular and Oncologic Disease After a Diagnosis of Early-Stage Cancer. Semin Oncol 2013; 40:218-28. [DOI: 10.1053/j.seminoncol.2013.01.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Weigent DA. High molecular weight isoforms of growth hormone in cells of the immune system. Cell Immunol 2011; 271:44-52. [PMID: 21741628 DOI: 10.1016/j.cellimm.2011.06.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2011] [Revised: 05/06/2011] [Accepted: 06/01/2011] [Indexed: 01/05/2023]
Abstract
A substantial body of research exists to support the idea that cells of the immune system produce growth hormone (GH). However, the structure and mechanism of action of lymphocyte-derived GH continues to remain largely unknown. Here we present the results of Western analysis of whole cell extracts showing that different molecular weight isoforms of GH of approximately 100, 65, and 48 kDa can be detected in primary mouse cells of the immune system and in the mouse EL4 cell line. The identity of the 65 and 48 kDa isoforms of GH were confirmed by mass spectrometry. The various isoforms were detected in both enriched T and B spleen cell populations. The large molecular weight isoform appears to reside primarily in the cytoplasm, whereas the lower molecular weight 65 and 48 kDa isoforms were detected primarily in the nucleus. These results also suggest that GH isoforms are induced by oxidative stress. In EL4 cells overexpressing GH, the expression of luciferase controlled by a promoter containing the antioxidant response element is increased almost threefold above control. The data suggest that the induction of isoforms of the GH molecule in cells of the immune system may be an important mechanism of adaptation and/or protection of lymphoid cells under conditions of oxidative stress.
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Affiliation(s)
- Douglas A Weigent
- University of Alabama at Birmingham, Department of Physiology and Biophysics, Birmingham, AL 35294-0005, United States.
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Effects of exercise training on the matrix metalloprotease response to acute exercise. Eur J Appl Physiol 2009; 106:655-63. [DOI: 10.1007/s00421-009-1063-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2009] [Indexed: 11/25/2022]
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