1
|
Iwase H, Ball S, Adams K, Eyestone W, Walters A, Cooper DKC. Growth hormone receptor knockout: Relevance to xenotransplantation. Xenotransplantation 2020; 28:e12652. [PMID: 33058285 DOI: 10.1111/xen.12652] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/03/2020] [Accepted: 09/15/2020] [Indexed: 02/06/2023]
Abstract
Xenotransplantation research has made considerable progress in recent years, largely through the increasing availability of pigs with multiple genetic modifications, effective immunosuppressive therapy, and anti-inflammatory therapy to protect pig tissues from the primate immune and inflammatory responses and correct molecular incompatibilities. Further study is required regarding identification and investigation of physiological incompatibilities. Although the exact cause remains uncertain, we and others have observed relatively rapid growth of kidney xenografts after transplantation into nonhuman primates (NHPs). There has also been some evidence of growth, or at least ventricular hypertrophy, of the pig heart after orthotopic transplantation into NHPs. Rapid growth could be problematic, particularly with regard to the heart within the relatively restricted confines of the chest. It has been suggested that the problem of rapid growth of the pig organ after transplantation could be resolved by growth hormone receptor (GHR) gene knockout in the pig. The GHR, although most well-known for regulating growth, has many other biological functions, including regulating metabolism and controlling physiological processes. Genetically modified GHRKO pigs have recently become available. We provide data on their growth compared to comparable pigs that do not include GHRKO, and we have reviewed the literature regarding the effect of GHRKO, and its relevance to xenotransplantation.
Collapse
Affiliation(s)
- Hayato Iwase
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | | | | | - David K C Cooper
- Xenotransplantation Program, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
2
|
Unnikrishnan A, Kurup K, Salmon AB, Richardson A. Is Rapamycin a Dietary Restriction Mimetic? J Gerontol A Biol Sci Med Sci 2020; 75:4-13. [PMID: 30854544 PMCID: PMC6909904 DOI: 10.1093/gerona/glz060] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 02/28/2019] [Indexed: 01/21/2023] Open
Abstract
Since the initial suggestion that rapamycin, an inhibitor of target of rapamycin (TOR) nutrient signaling, increased lifespan comparable to dietary restriction, investigators have viewed rapamycin as a potential dietary restriction mimetic. Both dietary restriction and rapamycin increase lifespan across a wide range of evolutionarily diverse species (including yeast, Caenorhabditis elegans, Drosophila, and mice) as well as reducing pathology and improving physiological functions that decline with age in mice. The purpose of this article is to review the research comparing the effect of dietary restriction and rapamycin in mice. The current data show that dietary restriction and rapamycin have different effects on many pathways and molecular processes. In addition, these interventions affect the lifespan of many genetically manipulated mouse models differently. In other words, while dietary restriction and rapamycin may have similar effects on some pathways and processes; overall, they affect many pathways/processes quite differently. Therefore, rapamycin is likely not a true dietary restriction mimetic. Rather dietary restriction and rapamycin appear to be increasing lifespan and retarding aging largely through different mechanisms/pathways, suggesting that a combination of dietary restriction and rapamycin will have a greater effect on lifespan than either manipulation alone.
Collapse
Affiliation(s)
- Archana Unnikrishnan
- Reynolds Oklahoma Center on Aging and Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City
| | - Kavitha Kurup
- Reynolds Oklahoma Center on Aging and Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City
| | - Adam B Salmon
- Department of Molecular Medicine and the Sam and Ann Barhop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio,Geratric Research Education and Clinical Center, South Texas Veterans Health Care System, San Antonio
| | - Arlan Richardson
- Reynolds Oklahoma Center on Aging and Department of Biochemistry & Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City,Oklahoma City VA Medical Center, Oklahoma,Address correspondence to: Arlan Richardson, PhD, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center, 975 NE 10th Street, BRC 1372, Oklahoma City, OK 73104. E-mail:
| |
Collapse
|
3
|
Gesing A, Wiesenborn D, Do A, Menon V, Schneider A, Victoria B, Stout MB, Kopchick JJ, Bartke A, Masternak MM. A Long-lived Mouse Lacking Both Growth Hormone and Growth Hormone Receptor: A New Animal Model for Aging Studies. J Gerontol A Biol Sci Med Sci 2017; 72:1054-1061. [PMID: 27688483 DOI: 10.1093/gerona/glw193] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 09/13/2016] [Indexed: 11/14/2022] Open
Abstract
Disruption of the growth hormone (GH) signaling pathway promotes insulin sensitivity and is associated with both delayed aging and extended longevity. Two kinds of long-lived mice-Ames dwarfs (df/df) and GH receptor gene-disrupted knockouts (GHRKO) are characterized by a suppressed GH axis with a significant reduction of body size and decreased plasma insulin-like growth factor-1 (IGF-1) and insulin levels. Ames dwarf mice are deficient in GH, prolactin, and thyrotropin, whereas GHRKOs are GH resistant and are dwarf with decreased circulating IGF-1 and increased GH. Crossing Ames dwarfs and GHRKOs produced a new mouse line (df/KO), lacking both GH and GH receptor. These mice are characterized by improved glucose tolerance and increased adiponectin level, which could imply that these mice should be also characterized by additional life-span extension when comparing with GHRKOs and Ames dwarfs. Importantly, our longevity experiments showed that df/KO mice maintain extended longevity when comparing with N control mice; however, they do not live longer than GHRKO and Ames df/df mice. These important findings indicate that silencing GH signal is important to extend the life span; however, further decrease of body size in mice with already inhibited GH signal does not extend the life span regardless of improved some health-span markers.
Collapse
Affiliation(s)
- Adam Gesing
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando.,Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield.,Department of Oncological Endocrinology, Medical University of Lodz, Poland
| | - Denise Wiesenborn
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando.,Department of Medical Biochemistry and Molecular Biology, University of Saarland, Homburg, Germany.,Department of Biotechnology, University of Applied Sciences Kaiserslautern, Zweibrücken, Germany
| | - Andrew Do
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando.,Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton
| | - Vinal Menon
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando.,Department of Cell Biology and Anatomy, School of Medicine, University of South Carolina, Columbia
| | - Augusto Schneider
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando.,Faculdade de Nutrição, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | - Berta Victoria
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando
| | - Michael B Stout
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - John J Kopchick
- Edison Biotechnology Institute and Heritage College of Osteopathic Medicine, Ohio University, Athens
| | - Andrzej Bartke
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield
| | - Michal M Masternak
- College of Medicine, Burnett School of Biomedical Sciences, University of Central Florida, Orlando.,Department of Head and Neck Surgery, The Greater Poland Cancer Centre, Poznan, Poland
| |
Collapse
|
4
|
Zhang L, Wang YY, Fu MZ, Li G, An N, Li SY, Zhou ZQ. The effects of ovariectomy on meat performance and expression of GH/IGF-I in young goats. CANADIAN JOURNAL OF ANIMAL SCIENCE 2014. [DOI: 10.4141/cjas-2014-001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Zhang, L., Wang, Y.-y., Fu, M.-z., Li, G., An, N., Li, S.-y. and Zhou, Z.-q. 2014. The effects of ovariectomy on meat performance and expression of GH/IGF-I in young goats. Can. J. Anim. Sci. 94: 619–626. Experiments were carried out to investigate the effects of ovariectomy on meat production efficiency and to explore the expression of GH/IGF-I in young goats. Animal performance, meat quality, levels of serum growth hormone (GH) and insulin-like growth factor 1 (IGF-I), and mRNA levels of three key genes [GH Receptor (GHR), IGF-I and IGF-I Receptor (IGF-IR)] in longissimus dorsi and biceps femoris muscles were measured. The results show that carcass weight, net meat mass, fat weight and loin eye area of ovariectomized goats were higher than those of the controls, and ovariectomized goats lost 0.40 kg of bone weight (P<0.05). There was no statistically valid difference for the color, pH, water-holding capacity, or cooking rate of meat (P>0.05) between the two groups, except for the shear value, which was significantly lower in the Ovx group than in the control group (P<0.05). The results of this research show for the first time a significant trend (P<0.05) for serum GH and IGF-I in the direction of increasing in ovariectomized goats. Furthermore, the mRNA levels of GHR, IGF-I and IGF-IR in muscle were all up-regulated, except for the IGF-I gene in biceps femoris, by ovariectomy. In summary, ovariectomy showed a beneficial promotion in animal performance, but did not reduce meat quality, and increased serum GH and IGF-I and mRNA expression levels of GHR, IGF-I and IGF-IR in young female goats.
Collapse
Affiliation(s)
- Lei Zhang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Yan-yan Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ming-zhe Fu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Guang Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Ning An
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| | - Si-yao Li
- College of Animal Science and Technology, South China Agricultural University, Guangzhou, Guangdong 510642, China
| | - Zhan-qin Zhou
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, China
| |
Collapse
|
5
|
Gesing A, Masternak MM, Lewinski A, Karbownik-Lewinska M, Kopchick JJ, Bartke A. Decreased levels of proapoptotic factors and increased key regulators of mitochondrial biogenesis constitute new potential beneficial features of long-lived growth hormone receptor gene-disrupted mice. J Gerontol A Biol Sci Med Sci 2013; 68:639-51. [PMID: 23197187 PMCID: PMC3708518 DOI: 10.1093/gerona/gls231] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 10/19/2012] [Indexed: 01/06/2023] Open
Abstract
Decreased somatotrophic signaling is among the most important mechanisms associated with extended longevity. Mice homozygous for the targeted disruption of the growth hormone (GH) receptor gene (GH receptor knockout; GHRKO) are obese and dwarf, are characterized by a reduced weight and body size, undetectable levels of GH receptor, high concentration of serum GH, and greatly reduced plasma levels of insulin and insulin-like growth factor-I, and are remarkably long lived. Recent results suggest new features of GHRKO mice that may positively affect longevity-decreased levels of proapoptotic factors and increased levels of key regulators of mitochondrial biogenesis. The alterations in levels of the proapoptotic factors and key regulators of mitochondrial biogenesis were not further improved by two other potential life-extending interventions-calorie restriction and visceral fat removal. This may attribute the primary role to GH resistance in the regulation of apoptosis and mitochondrial biogenesis in GHRKO mice in terms of increased life span.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Oncological Endocrinology, Medical University of Lodz, Lodz, Poland.
| | | | | | | | | | | |
Collapse
|
6
|
Gesing A, Bartke A, Masternak MM, Lewiński A, Karbownik-Lewińska M. Decreased thyroid follicle size in dwarf mice may suggest the role of growth hormone signaling in thyroid growth regulation. Thyroid Res 2012; 5:7. [PMID: 22897932 PMCID: PMC3464137 DOI: 10.1186/1756-6614-5-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 08/08/2012] [Indexed: 12/31/2022] Open
Abstract
Background Altered somatotrophic signaling is among the most important potential mechanisms of extended longevity. Ames dwarf (df/df) mice are homozygous for mutation at the Prop-1 gene, leading to a lack of growth hormone (GH), prolactin and thyroid stimulating hormone (TSH). Mice homozygous for targeted disruption of the growth hormone receptor/growth hormone binding protein gene are known as GH receptor knockout (GHRKO) mice or “Laron dwarf”. Both, df/df and GHRKO mice, are characterized by reduced body size, low plasma insulin and insulin-like growth factor-I (IGF-I), remarkably extended longevity, and severe (in df/df mice) or mild (in GHRKO mice) thyroid hypofunction. Recently, by crossing df/df and GHRKO mice, double-mutant Ames dwarf/GHRKO (df/KO) mice were created. Interestingly, these mice are smaller than Ames dwarfs or GHRKOs, and also have reduced insulin and IGF-I levels. The aim of the study was to investigate if and to what extent certain thyroid morphological parameters, such as inner follicular surface area, inner follicular perimeter, as well as the follicular epithelium thickness are changed in the examined dwarf mice. Methods This quantification was performed in thyroids collected from df/df, GHRKO and df/KO female mice, at approximately 5–6 months of age. We used a computerized plotting programme that combines a live microscopic image of the slide with an operator-generated overlay. Results Inner follicular surface area and inner follicular perimeter were decreased in all examined kinds of dwarf mice as compared to normal animals. Furthermore, decreases in these two parameters were more pronounced in df/df and df/KO than in GHRKO mice. Concerning the follicular epithelium thickness, only a tendency towards decrease of this parameter was found in all three kinds of dwarf mice. Conclusions Parameters characterizing thyroid follicle size are decreased in all three examined models of dwarf mice, which may explain decreased thyroid hormone levels in both basal mutants (Ames dwarfs and GHRKOs). df/df mutation seems to predominate over GHRKO genetic intervention concerning their effects on thyroid growth. Beside TSH, also GH signaling seems to constitute a crucial element in the regulation of thyroid growth and, possibly, function.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Oncological Endocrinology, Chair of Endocrinology and Metabolic Diseases, Medical University of Lodz, Lodz, Poland.
| | | | | | | | | |
Collapse
|
7
|
Gesing A, Masternak MM, Wang F, Karbownik-Lewinska M, Bartke A. Deletion of growth hormone receptor gene but not visceral fat removal decreases expression of apoptosis-related genes in the kidney-potential mechanism of lifespan extension. AGE (DORDRECHT, NETHERLANDS) 2012; 34:295-304. [PMID: 21431351 PMCID: PMC3312636 DOI: 10.1007/s11357-011-9232-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Accepted: 03/02/2011] [Indexed: 05/30/2023]
Abstract
Mice homozygous for the targeted disruption of the growth hormone (GH) receptor (Ghr) gene (GH receptor knockout; GHRKO; KO) are hypoinsulinemic, highly insulin sensitive, normoglycemic, and long-lived. Visceral fat removal (VFR) is a surgical intervention which improves insulin signaling in normal (N) mice and rats and extends longevity in rats. We have previously demonstrated decreased expression level of certain pro-apoptotic genes in skeletal muscles and suggested that this may contribute to the regulation of longevity in GHRKO mice. Alterations in apoptosis-related genes expression in the kidneys also may potentially lead to lifespan extension. In this context, we decided to examine the renal expression of the following genes: caspase-3, caspase-9, caspase-8, bax, bad, bcl-2, Smac/DIABLO, Apaf-1, p53, and cytochrome c1 (cyc1) in male GHRKO and N mice subjected to VFR or sham surgery, at approximately 6 months of age. The kidneys were collected 2 months after VFR. As a result, caspase-3, caspase-9, and bax expressions were decreased in KO mice as compared to N animals. Expressions of Smac/DIABLO, caspase-8, bcl-2, bad, and p53 did not differ between KOs and N mice. VFR did not change the expression of the examined genes in KO or N mice. In conclusion, endocrine abnormalities in GHRKO mice result in decreased expression of pro-apoptotic genes and VFR did not alter the examined genes expression in N and KO mice. These data are consistent with a model in which alterations of GH signaling and/or insulin sensitivity lead to increased lifespan mediated by decreased renal expression of pro-apoptotic genes.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield, IL 62702-4910, USA.
| | | | | | | | | |
Collapse
|
8
|
Gesing A, Masternak MM, Wang F, Joseph AM, Leeuwenburgh C, Westbrook R, Lewinski A, Karbownik-Lewinska M, Bartke A. Expression of key regulators of mitochondrial biogenesis in growth hormone receptor knockout (GHRKO) mice is enhanced but is not further improved by other potential life-extending interventions. J Gerontol A Biol Sci Med Sci 2011; 66:1062-76. [PMID: 21788651 DOI: 10.1093/gerona/glr080] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Mitochondrial biogenesis is essential for cell viability. Growth hormone receptor knockout (GHRKO), calorie restriction, and surgical visceral fat removal constitute experimental interventions to delay aging and increase life span. We examined the expression of known regulators of mitochondriogenesis: peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), adenosine monophosphate (AMP)-activated protein kinase (AMPK), sirtuin-1 (SIRT-1) and sirtuin-3 (SIRT-3), endothelial nitric oxide synthase (eNOS), nuclear respiratory factor-1, mitochondrial transcription factor A (TFAM), and mitofusin-2 (MFN-2) in the skeletal muscles and hearts of control and calorie-restricted female GHRKO mice and in the kidneys of male GHRKOs after visceral fat removal or sham surgery. Expression of PGC-1α in skeletal muscles, AMPK, SIRT-1, SIRT-3, eNOS, and MFN-2 in the heart and PGC-1α, AMPK, SIRT-3, eNOS, and MFN-2 in kidneys was increased in GHRKO mice but was not affected by calorie restriction or visceral fat removal. GHRKO mice have increased expression of key regulators of mitochondriogenesis, which is not improved further by calorie restriction or visceral fat removal.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Oncological Endocrinology, Medical University of Lodz, Zeligowski St., No 7/9, 90-752 Lodz, Poland.
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Gesing A, Bartke A, Wang F, Karbownik-Lewinska M, Masternak MM. Key regulators of mitochondrial biogenesis are increased in kidneys of growth hormone receptor knockout (GHRKO) mice. Cell Biochem Funct 2011; 29:459-67. [PMID: 21755522 DOI: 10.1002/cbf.1773] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 04/06/2011] [Accepted: 05/17/2011] [Indexed: 11/10/2022]
Abstract
UNLABELLED The growth hormone receptor knockout (GHRKO) mice are remarkably long-lived and highly insulin sensitive. Alterations in mitochondrial biogenesis are associated with aging and various metabolic derangements. We have previously demonstrated increased gene expression of key regulators of mitochondriogenesis in kidneys, hearts and skeletal muscles of GHRKO mice. The aim of the present study was to quantify the protein levels of the following regulators of mitochondriogenesis: peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), AMP-activated protein kinase α (AMPKα), phospho-AMPKα (p-AMPKα), sirtuin-3 (SIRT-3), endothelial nitric oxide synthase (eNOS), phospho-eNOS (p-eNOS), nuclear respiratory factor-1 (NRF-1) and mitofusin-2 (MFN-2) in skeletal muscles and kidneys of GHRKOs in comparison to normal mice. We also were interested in the effects of calorie restriction (CR) and visceral fat removal (VFR) on these parameters. Both CR and VFR improve insulin sensitivity and can extend life span. RESULTS The renal levels of PGC-1α, AMPKα, p-AMPKα, SIRT-3, eNOS, p-eNOS and MFN-2 were increased in GHRKOs. In the GHRKO skeletal muscles, only MFN-2 was increased. Levels of the examined proteins were not affected by CR (except for PGC-1α and p-eNOS in skeletal muscles) or VFR. CONCLUSION GHRKO mice have increased renal protein levels of key regulators of mitochondriogenesis, and this may contribute to increased longevity of these knockouts.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield, IL, USA.
| | | | | | | | | |
Collapse
|
10
|
Gesing A, Masternak MM, Wang F, Lewinski A, Karbownik-Lewinska M, Bartke A. Decreased expression level of apoptosis-related genes and/or proteins in skeletal muscles, but not in hearts, of growth hormone receptor knockout mice. Exp Biol Med (Maywood) 2011; 236:156-68. [PMID: 21321312 DOI: 10.1258/ebm.2010.010202] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The long-lived growth hormone (GH) receptor knockout (GHRKO; KO) mice are GH-resistant due to targeted disruption of the GH receptor (Ghr) gene. Apoptosis is a physiological process in which cells play an active role in their own death and is a normal component of the development and health of multicellular organisms. Aging is associated with the progressive loss of strength of skeletal and heart muscles. Calorie restriction (CR) is a well-known experimental model to delay aging and increase lifespan. The aim of the study was to examine the expression of the following apoptosis-related genes: caspase-3, caspase-9, caspase-8, bax, bcl-2, Smac/DIABLO, p53 and cytochrome c1 (cyc1) in the skeletal muscles and hearts of female normal and GHRKO mice, fed ad libitum or subjected to 40% CR for six months, starting at two months of age. Moreover, skeletal muscle caspase-3, caspase-9, caspase-8, bax, bcl-2, Smac/DIABLO, Apaf-1, bad, phospho-bad (pbad), phospho-p53 and cytochrome c (cyc) protein expression levels were assessed. Expression of caspase-3, caspase-9, bax and Smac/DIABLO genes and proteins was decreased in GHRKO's skeletal muscles. The Apaf-1 protein expression also was diminished in this tissue. In contrast, bcl-2 and pbad protein levels were increased in skeletal muscles in knockouts. No changes were demonstrated for the examined genes' expression in GHRKO's hearts except for the increased level of cyc1 mRNA. CR did not alter the expression of the examined genes and proteins in skeletal muscles of knockouts versus normal (N) mice. In heart homogenates, CR increased caspase-3 mRNA level as compared with ad libitum mice. Decreased expression of certain proapoptotic genes and/or proteins may constitute the potential mechanism of prolonged longevity in GHRKO mice, protecting these animals from aging; this potential beneficial mechanism is not affected by CR.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, 801 N Rutledge St., Room 4389, 62702-4910 Springfield, IL, USA.
| | | | | | | | | | | |
Collapse
|
11
|
Gesing A, Bartke A, Wang F, Karbownik-Lewinska M, Masternak MM. Renal pro-apoptotic proteins are reduced by growth hormone resistance but not by visceral fat removal. Biol Chem 2011; 392:475-81. [PMID: 21391871 DOI: 10.1515/bc.2011.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Growth hormone (GH) receptor knockout (GHRKO) mice are highly insulin sensitive and long-lived. Surgical visceral fat removal (VFR) improves insulin signaling in normal mice and rats and extends longevity in rats. We have previously demonstrated decreased expression of certain pro-apoptotic genes in kidneys of GHRKO mice and suggested that this could contribute to the increased longevity of these animals. The aim of the present study was to examine the level of the following proteins: caspase-3, caspase-9, caspase-8, bax, bad, phospho-bad, bcl-2, Smac/DIABLO, Apaf-1, phospho-p53 (pp53) and cytochrome c in male GHRKO and normal (N) mice subjected to VFR or sham surgery, at approximately six months of age. The kidneys were collected two months after VFR. Caspase-3, caspase-8, bax, bad, Smac/DIABLO, Apaf-1 and pp53 levels were decreased in GHRKO mice as compared to N animals. VFR did not change the level of any of the examined proteins. The decreased renal levels of pro-apoptotic proteins could contribute to the extended life-span caused by targeted disruption of the GH receptor gene but are apparently not involved in mediating the effects of VFR.
Collapse
Affiliation(s)
- Adam Gesing
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield, IL 62702-4910, USA. adges7wp.pl
| | | | | | | | | |
Collapse
|