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Priyadarsini N, Nanda P, Devi S, Mohapatra S. Sarcopenia: An Age-Related Multifactorial Disorder. Curr Aging Sci 2022; 15:209-217. [PMID: 35249518 DOI: 10.2174/1874609815666220304194539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 12/22/2021] [Accepted: 12/28/2021] [Indexed: 11/22/2022]
Abstract
Sarcopenia is an emerging clinical entity characterized by a gradual decline in skeletal muscle mass and strength that accompanies the normal aging process. It has been noted that sarcopenia is associated with various adverse health outcomes in the geriatric population like prolonged hospital admission, disability, poor quality of life, frailty, and mortality. Factors involved in the development of age-related sarcopenia include anorexia, alteration in the hormone levels, decreased neural innervation, low blood flow to the muscles, cytokine dysregulation, altered mitochondrial activity, genomic instability, intracellular proteolysis, and insulin resistance. Understanding the mechanism may help develop efficient preventive and therapeutic strategies which can improve the quality of life in elderly individuals. Thus, the objective of the present article is to review the literature regarding the mechanism involved in the development of sarcopenia in aged individuals.
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Affiliation(s)
- Nibedita Priyadarsini
- Department of Physiology, All India Institute of Medical Sciences, Bhubaneswar, India
| | - Pranati Nanda
- Department of Physiology, All India Institute of Medical Sciences, Bhubaneswar, India
| | - Sujata Devi
- Department of Medicine, All India Institute of Medical Sciences, Bhubaneswar, India
| | - Subarna Mohapatra
- Department of Physiology, All India Institute of Medical Sciences, Bhubaneswar, India
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Banitalebi E, Faramarzi M, Bagheri L, Kazemi AR. Comparison of performing 12 weeks' resistance training before, after and/or in between aerobic exercise on the hormonal status of aged women: a randomized controlled trial. Horm Mol Biol Clin Investig 2018; 35:/j/hmbci.ahead-of-print/hmbci-2018-0020/hmbci-2018-0020.xml. [PMID: 30205658 DOI: 10.1515/hmbci-2018-0020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/19/2018] [Indexed: 02/07/2023]
Abstract
Background Physiological aging can now be considered as a multi-factorial process that is associated with anatomical and signaling changes associated with endocrine function. The purpose of this study was to investigate the comparison of performing 12 weeks' resistance training before, after and/or in between aerobic exercise on the hormonal status of aged women. Materials and methods Forty healthy aged women (age: 67.35 ± 1.40 years) were randomly divided into three training groups and a control group: resistance followed by endurance training (ER, n = 12), endurance training followed by resistance training (RE, n = 12, interval resistance-endurance (RE) training (INT, n = 12) and a control (Con, n = 12) groups. The training program was done over 12 weeks, 3 times per week. Endurance training was performed on a cycle ergometer (intensity: 60-90% maximum heart rate) and resistance training involved selected resistance exercises (intensity: 40-75 one-repetition maximum, 8-18 repeats). All participants were evaluated before and after the training period. Results and conclusion The data showed that performing resistance training before, after and/or in between aerobic exercise did not influence the adaptive response of insulin like growth factor-1 (IGF-1) (p = 0.07), growth hormone (p = 0.35), cortisol (p = 0.20), insulin (p = 0.72), epinephrine (p = 0.83) and norepinephrine (p = 0.86) levels throughout the study. However, when comparing pre and post, no significant differences were shown following combined training within the SE, ES and INT groups for all variables (p < 0.05), except of IGF-1 within ES (p = 0.04) and SE (p = 0.02), and testosterone within ES (p = 0.007). In conclusion, combined training with RE order may be more effective than other orders for increasing anabolic status in aged women.
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Affiliation(s)
| | - Mohammad Faramarzi
- Department of Sport Science, Shahrekord University, Shahrekord, Iran, Phone: +983814424403, Fax: +983814424403
| | - Laleh Bagheri
- Department of Sport Sciences, Shahrekord University, Shahrekord, Iran
| | - Abdol Reza Kazemi
- Department of Sport Sciences, Valiaaser University, Rafsanjan, Kerman, Iran
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van Nieuwpoort IC, Vlot MC, Schaap LA, Lips P, Drent ML. The relationship between serum IGF-1, handgrip strength, physical performance and falls in elderly men and women. Eur J Endocrinol 2018; 179:73-84. [PMID: 29789408 DOI: 10.1530/eje-18-0076] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/22/2018] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Human aging is accompanied by a decrease in growth hormone secretion and serum insulin-like growth factor (IGF)-1 levels. Also, loss of muscle mass and strength and impairment of physical performance, ending in a state of frailty, are seen in elderly. We aimed to investigate whether handgrip strength, physical performance and recurrent falls are related to serum IGF-1 levels in community-dwelling elderly. DESIGN Observational cohort study (cross-sectional and prospective). METHODS We studied the association between IGF-1 and handgrip strength, physical performance and falls in participants of the Longitudinal Aging Study Amsterdam. A total of 1292 participants were included (633 men, 659 women). Serum IGF-1 levels were divided into quartiles (IGF-1-Q1 to IGF-1-Q4). Data on falls were collected prospectively for a period of 3 years. All analyses were stratified for age and physical activity and adjusted for relevant confounders. RESULTS Men with a low physical activity score in IGF-1-Q1 and IGF-1-Q2 of the younger age group had a lower handgrip strength compared to IGF-1-Q4. In younger more active males in IGF-1-Q2 physical performance was worse. Recurrent fallers were less prevalent in older, low active males with low IGF-1 levels. In females, recurrent fallers were more prevalent in older, more active females in IGF-1-Q2. IGF-1 quartile may predict changes in handgrip strength and physical performance in men and women. CONCLUSIONS Our results indicate that lower IGF-1 levels are associated with lower handgrip strength and worse physical performance, but less recurrent fallers especially in men. Associations were often more robust in IGF-1-Q2. Future studies on this topic are desirable.
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Affiliation(s)
- I C van Nieuwpoort
- Department of Internal Medicine, Section Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - M C Vlot
- Department of Internal Medicine, Section Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
| | - L A Schaap
- Department of Health Sciences, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam Public Health Research Institute, Amsterdam, The Netherlands
| | - P Lips
- Department of Internal Medicine, Section Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
- Institute for Research in Extramural Medicine (EMGO Institute), VU University Medical Center, Amsterdam, The Netherlands
| | - M L Drent
- Department of Internal Medicine, Section Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
- Amsterdam Neuroscience, Amsterdam, The Netherlands
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Ilich JZ, Kelly OJ, Inglis JE. Osteosarcopenic Obesity Syndrome: What Is It and How Can It Be Identified and Diagnosed? Curr Gerontol Geriatr Res 2016; 2016:7325973. [PMID: 27667996 PMCID: PMC5030469 DOI: 10.1155/2016/7325973] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 08/07/2016] [Indexed: 01/07/2023] Open
Abstract
Conditions related to body composition and aging, such as osteopenic obesity, sarcopenia/sarcopenic obesity, and the newly termed osteosarcopenic obesity (triad of bone muscle and adipose tissue impairment), are beginning to gain recognition. However there is still a lack of definitive diagnostic criteria for these conditions. Little is known about the long-term impact of these combined conditions of osteoporosis, sarcopenia, and obesity in older adults. Many may go undiagnosed and progress untreated. Therefore, the objective of this research is to create diagnostic criteria for osteosarcopenic obesity in older women. The proposed diagnostic criteria are based on two types of assessments: physical, via body composition measurements, and functional, via physical performance measures. Body composition measurements such as T-scores for bone mineral density, appendicular lean mass for sarcopenia, and percent body fat could all be obtained via dual energy X-ray absorptiometry. Physical performance tests: handgrip strength, one-leg stance, walking speed, and sit-to-stand could be assessed with minimal equipment. A score could then be obtained to measure functional decline in the older adult. For diagnosing osteosarcopenic obesity and other conditions related to bone loss and muscle loss combined with obesity, a combination of measures may more adequately improve the assessment process.
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Affiliation(s)
- Jasminka Z. Ilich
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA
| | | | - Julia E. Inglis
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, USA
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Behringer V, Wudy SA, Blum WF, Stevens JMG, Remer T, Boesch C, Hohmann G. Sex Differences in Age-Related Decline of Urinary Insulin-Like Growth Factor-Binding Protein-3 Levels in Adult Bonobos and Chimpanzees. Front Endocrinol (Lausanne) 2016; 7:118. [PMID: 27602019 PMCID: PMC4994059 DOI: 10.3389/fendo.2016.00118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 08/11/2016] [Indexed: 12/27/2022] Open
Abstract
There is increasing interest in the characterization of normative senescence in humans. To assess to what extent aging patterns in humans are unique, comparative data from closely related species, such as non-human primates, can be very useful. Here, we use data from bonobos and chimpanzees, two closely related species that share a common ancestor with humans, to explore physiological markers that are indicative of aging processes. Many studies on aging in humans focus on the somatotropic axis, consisting of growth hormone (GH), insulin-like growth factors (IGFs), and IGF binding proteins (IGFBPs). In humans, IGFBP-3 levels decline steadily with increasing age. We used urinary IGFBP-3 levels as an alternative endocrine marker for IGF-I to identify the temporal pattern known to be related with age-related changes in cell proliferation, growth, and apoptosis. We measured urinary IGFBP-3 levels in samples from 71 bonobos and 102 chimpanzees. Focusing on samples from individuals aged 10 years or older, we found that urinary IGFBP-3 levels decline in both ape species with increasing age. However, in both species, females start with higher urinary IGFBP-3 levels than males, experience a steeper decline with increasing age, and converge with male levels around the age of 30-35 years. Our measurements of urinary IGFBP-3 levels indicate that bonobos and chimpanzees mirror human patterns of age-related decline in IGFBP-3 in older individuals (<10 years) of both sexes. Moreover, such as humans, both ape species show sex-specific differences in IGFBP-3 levels with females having higher levels than males, a result that correlates with sex differences in life expectancy. Using changes in urinary IGFBP-3 levels as a proxy for changes in GH and IGF-I levels that mark age-related changes in cell proliferation, this approach provides an opportunity to investigate trade-offs in life-history strategies in cross-sectional and in longitudinal studies, both in captivity and in the wild.
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Affiliation(s)
- Verena Behringer
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- *Correspondence: Verena Behringer,
| | - Stefan A. Wudy
- Laboratory for Translational Hormone Analytics in Paediatric Endocrinology, Center of Child and Adolescent Medicine, Justus-Liebig-University, Giessen, Germany
| | - Werner F. Blum
- Laboratory for Translational Hormone Analytics in Paediatric Endocrinology, Center of Child and Adolescent Medicine, Justus-Liebig-University, Giessen, Germany
| | - Jeroen M. G. Stevens
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
| | - Thomas Remer
- DONALD Study Dortmund, IEL-Nutritional Epidemiology, University of Bonn, Dortmund, Germany
| | - Christophe Boesch
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Gottfried Hohmann
- Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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McMahon CD, Chai R, Radley-Crabb HG, Watson T, Matthews KG, Sheard PW, Soffe Z, Grounds MD, Shavlakadze T. Lifelong exercise and locally produced insulin-like growth factor-1 (IGF-1) have a modest influence on reducing age-related muscle wasting in mice. Scand J Med Sci Sports 2014; 24:e423-435. [DOI: 10.1111/sms.12200] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2014] [Indexed: 12/25/2022]
Affiliation(s)
| | - R. Chai
- School of Anatomy, Physiology & Human Biology; The University of Western Australia; Nedlands Western Australia Australia
| | - H. G. Radley-Crabb
- School of Anatomy, Physiology & Human Biology; The University of Western Australia; Nedlands Western Australia Australia
- School of Biomedical Sciences; CHIRI Biosciences Research Precinct; Faculty of Health Sciences; Curtin University; Bentley Western Australia Australia
| | - T. Watson
- Agresearch Ltd; Hamilton New Zealand
| | | | - P. W. Sheard
- Department of Physiology; University of Otago; Dunedin New Zealand
| | - Z. Soffe
- School of Anatomy, Physiology & Human Biology; The University of Western Australia; Nedlands Western Australia Australia
| | - M. D. Grounds
- School of Anatomy, Physiology & Human Biology; The University of Western Australia; Nedlands Western Australia Australia
| | - T. Shavlakadze
- School of Anatomy, Physiology & Human Biology; The University of Western Australia; Nedlands Western Australia Australia
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Park JE, Lee ST, Im WS, Kim M. Growth Hormone Deteriorates the Functional Outcome in an Experimental Model of Huntington's Disease Induced by 3-Nitropionic Acid. J Mov Disord 2013; 6:28-33. [PMID: 24868423 PMCID: PMC4027642 DOI: 10.14802/jmd.13007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 06/14/2013] [Accepted: 08/20/2013] [Indexed: 12/18/2022] Open
Abstract
Background and Purpose: Growth hormone (GH) has been frequently used to control the aging process in healthy individuals, probably due to its slowing effect on senescence-associated degeneration. Mitochondrial dysfunction is related to the aging process, and one of the chemical models of Huntington’s disease is that it can be induced by mitochondrial toxin. To investigate the potential application of GH to modify the progression of Huntington’s disease (HD), we examined whether GH can protect the functional deterioration by striatal damage induced by 3-nitropropionic acid (3NP). Methods: 3NP (63 mg/kg/day) was delivered to Lewis rats by osmotic pumps for five consecutive days, and the rats received intraperitoneal administration of GH or vehicle (saline) throughout the experiment. Neurological deficits and body weight were monitored. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was performed to further determine the mitochondrial activity in cultured N18TG2 neuroblastoma cells in vitro. Results: 3NP-treated rats showed progressive neurologic deficits with striatal damage. Application of GH accelerated behavioral deterioration, particularly between day 3 and day 5, resulting in reduced survival outcome. The body weights of rats given 3NP were decreased, but GH did not affect such decrease compared to the non-treated control group. The effect of GH on cultured neuronal cells was a decrease in the MTT absorbance, suggesting a lower number of cells in a dose dependent pattern. Conclusions: Those results suggest that application of GH to a 3NP-induced experimental model of HD deteriorates the progress of functional deficits, possibly disturbing mitochondrial activities.
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Affiliation(s)
- Jung-Eun Park
- Department of Neurology, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea ; Program in Neuroscience, Seoul National University, Seoul, Korea
| | - Soon-Tae Lee
- Department of Neurology, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea ; Program in Neuroscience, Seoul National University, Seoul, Korea
| | - Woo-Seok Im
- Department of Neurology, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Manho Kim
- Department of Neurology, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea ; Program in Neuroscience, Seoul National University, Seoul, Korea
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Casadesus G, Shukitt-Hale B, Stellwagen HM, Zhu X, Lee HG, Smith MA, Joseph JA. Modulation of Hippocampal Plasticity and Cognitive Behavior by Short-term Blueberry Supplementation in Aged Rats. Nutr Neurosci 2013; 7:309-16. [PMID: 15682927 DOI: 10.1080/10284150400020482] [Citation(s) in RCA: 176] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
During aging, reductions in hippocampal neurogenesis are associated with memory decline indicating a causal relationship. Indeed, insulin-like growth factor-1 (IGF-1), a major activator of the extracellular receptor kinase pathway that is central in learning and memory processes, is also a key modulator of hippocampal neurogenesis. Previously, we showed that age-related declines in spatial memory tasks can be improved by antioxidant-rich diets containing blueberries. In this study, to begin to understand the mechanisms responsible for the beneficial effects of blueberries, we assessed changes in hippocampal plasticity parameters such as hippocampal neurogenesis, extracellular receptor kinase activation, and IGF-1 and IGF-1R levels in blueberry-supplemented aged animals. Our results show that all these parameters of hippocampal neuronal plasticity are increased in supplemented animals and aspects such as proliferation, extracellular receptor kinase activation and IGF-1 and IGF-1R levels correlate with improvements in spatial memory. Therefore, cognitive improvements afforded by polyphenolic-rich fruits such as blueberries appear, in part, to be mediated by their effects on hippocampal plasticity.
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Telegdy G, Tanaka M, Schally AV. Effects of the growth hormone-releasing hormone (GH-RH) antagonist on brain functions in mice. Behav Brain Res 2011; 224:155-8. [DOI: 10.1016/j.bbr.2011.05.036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 05/26/2011] [Accepted: 05/27/2011] [Indexed: 10/18/2022]
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Jakobsdóttir S, van Nieuwpoort IC, Schaap LA, van Schoor NM, Lips P, Drent ML. Serum insulin-like growth factor-I and body composition in community dwelling older people. Clin Endocrinol (Oxf) 2010; 73:173-80. [PMID: 19912246 DOI: 10.1111/j.1365-2265.2009.03747.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVES The decline in the growth hormone/insulin-like growth factor-I (GH/IGF-I) axis during normal aging might be involved in the changes in body composition associated with increasing age. We conducted a study to investigate serum IGF-I levels across different age categories and a possible association between serum IGF-I and measurements of body composition in older people. DESIGN A cross-sectional analysis of community dwelling older people, which participated in a large longitudinal cohort study (Longitudinal Aging Study Amsterdam). SUBJECTS 1319 subjects, 644 men, mean age 75.6 +/- 6.6 years and 675 women, mean age 75.4 +/- 6.6 years. MAIN OUTCOME MEASUREMENTS IGF-I, body mass index (BMI), waist, waist-hip ratio (WHR), fat mass, lean body mass and total bone mineral density. RESULTS IGF-I levels were significantly lower in the highest age categories. BMI and biceps skinfold measurements were lower in the lowest IGF-I quartile in men aged > or =75.5 years. In men with a low total physical activity score (<131 min/day), BMI, WHR and skinfolds were significantly lower in the lowest IGF-I quartile. In women with a high total physical activity score (>174 min/day), WHR was lower in the lowest IGF-I quartiles. CONCLUSION In this large cohort of community dwelling older people, we observed lower serum IGF-I levels in the higher age categories. A low serum IGF-I was associated with significantly lower measurements of body composition, such as BMI, skinfolds and WHR. These results do not support previous findings that high IGF-I levels are favourable for a healthy body composition in community dwelling older people.
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Affiliation(s)
- Sigridur Jakobsdóttir
- Department of Endocrinology, VU University Medical Center, Amsterdam, The Netherlands
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Marzetti E, Privitera G, Simili V, Wohlgemuth SE, Aulisa L, Pahor M, Leeuwenburgh C. Multiple pathways to the same end: mechanisms of myonuclear apoptosis in sarcopenia of aging. ScientificWorldJournal 2010; 10:340-9. [PMID: 20191247 PMCID: PMC4311890 DOI: 10.1100/tsw.2010.27] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Sarcopenia, the age-related decline in muscle mass and function, represents a significant health issue due to the high prevalence of frailty and disability associated with this condition. Nevertheless, the cellular mechanisms responsible for the loss of muscle mass in old age are still largely unknown. An altered regulation of myocyte apoptosis has recently emerged as a possible contributor to the pathogenesis of sarcopenia. Studies in animal models have shown that the severity of skeletal muscle apoptosis increases over the course of aging and correlates with the degree of muscle mass and strength decline. Several apoptotic pathways are operative in aged muscles, with the mitochondria- and TNF-α-mediated pathways likely being the most relevant to sarcopenia. However, despite the growing number of studies on the subject, a definite mechanistic link between myocyte apoptosis and age-related muscle atrophy has not yet been established. Furthermore, the evidence on the role played by apoptosis in human sarcopenia is still sparse. Clearly, further research is required to better define the involvement of myocyte apoptosis in the pathogenesis of muscle loss at advanced age. This knowledge will likely help in the design of more effective therapeutic strategies to preserve muscle mass into old age, thus fostering independence of the elderly population and reducing the socioeconomic burden associated with sarcopenia.
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Affiliation(s)
- Emanuele Marzetti
- Department of Aging and Geriatric Research, Institute on Aging, Division of Biology of Aging, University of Florida, Gainesville, USA.
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12
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Gan EH, Quinton R. Physiological Significance of the Rhythmic Secretion of Hypothalamic and Pituitary Hormones. PROGRESS IN BRAIN RESEARCH 2010; 181:111-26. [DOI: 10.1016/s0079-6123(08)81007-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Veldhuis JD, Hudson SB, Erickson D, Bailey JN, Reynolds GA, Bowers CY. Relative effects of estrogen, age, and visceral fat on pulsatile growth hormone secretion in healthy women. Am J Physiol Endocrinol Metab 2009; 297:E367-74. [PMID: 19470834 PMCID: PMC2724113 DOI: 10.1152/ajpendo.00230.2009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Growth hormone (GH) secretion is subject to complex regulation. How pre- and postmenopausal age (PRE, POST), estradiol (E(2)) availability, and abdominal visceral fat (AVF) jointly affect peptidyl-secretagogue drive of GH secretion is not known. To this end, healthy PRE (n = 20) and POST (n = 22) women underwent a low- vs. high-E(2) clamp before receiving a continuous intravenous infusion of GH-releasing hormone (GHRH) or GH-releasing peptide (GHRP-2). According to analysis of covariance, PRE and POST women achieved age-independent hypo- and euestrogenemia under respective low- and high-E(2) clamps. All four of age (P < 0.001), E(2) status (P = 0.006), secretagogue type (P < 0.001), and an age x peptide interaction (P = 0.014) controlled pulsatile GH secretion. Independently of E(2) status, POST women had lower GH responses to both GHRH (P = 0.028) and GHRP-2 (P < 0.001) than PRE women. Independently of age, GHRP-2 was more stimulatory than GHRH during low E(2) (P = 0.011) and high E(2) (P < 0.001). Stepwise forward-selection multivariate analysis revealed that computerized tomographic estimates of AVF explained 22% of the variability in GHRH action (P = 0.002), whereas age and E(2) together explained 60% of the variability in GHRP-2 drive (P < 0.001). These data establish that age, estrogen status, and AVF are triple covariates of continuous peptide-secretagogue drive of pulsatile GH secretion in women. Each factor must be controlled for to allow valid comparisons of GH-axis activity.
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Affiliation(s)
- Johannes D Veldhuis
- Departments of Internal Medicine, Endocrine Research Unit, Clinical Translational Research Unit, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, Minnesota, USA.
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Ziaei M, Tennant M, Sanders EJ, Harvey S. Vitreous growth hormone and visual dysfunction. Neurosci Lett 2009; 460:87-91. [DOI: 10.1016/j.neulet.2009.05.048] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Accepted: 05/15/2009] [Indexed: 11/25/2022]
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16
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Haus E. Chronobiology in the endocrine system. Adv Drug Deliv Rev 2007; 59:985-1014. [PMID: 17804113 DOI: 10.1016/j.addr.2007.01.001] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Accepted: 01/15/2007] [Indexed: 12/13/2022]
Abstract
Biological signaling occurs in a complex web with participation and interaction of the central nervous system, the autonomous nervous system, the endocrine glands, peripheral endocrine tissues including the intestinal tract and adipose tissue, and the immune system. All of these show an intricate time structure with rhythms and pulsatile variations in multiple frequencies. Circadian (about 24-hour) and circannual (about 1-year) rhythms are kept in step with the cyclic environmental surrounding by the timing and length of the daily light span. Rhythmicity of many endocrine variables is essential for their efficacy and, even in some instances, for the qualitative nature of their effects. Indeed, the continuous administration of certain hormones and their synthetic analogues may show substantially different effects than expected. In the design of drug-delivery systems and treatment schedules involving directly or indirectly the endocrine system, consideration of the human time organization is essential. A large amount of information on the endocrine time structure has accumulated, some of which is discussed in this review.
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Affiliation(s)
- Erhard Haus
- Department of Laboratory Medicine and Pathology, University of Minnesota, Health Partners Medical Group, Regions Hospital, 640 Jackson Street, St. Paul, Minnesota 55101, USA.
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Lyuh E, Kim HJ, Kim M, Lee JK, Park KS, Yoo KY, Lee KW, Ahn YO. Dose-specific or dose-dependent effect of growth hormone treatment on the proliferation and differentiation of cultured neuronal cells. Growth Horm IGF Res 2007; 17:315-322. [PMID: 17482859 DOI: 10.1016/j.ghir.2007.03.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 03/11/2007] [Accepted: 03/21/2007] [Indexed: 12/12/2022]
Abstract
OBJECTIVE GH controls the proliferation of cartilage, fibroblasts or the differentiation of adipose and muscle tissue. However, the effect of GH on neuronal cells remains unknown. The present study was conducted to determine the proliferative or differentiating effect of GH on the nervous system in vitro. DESIGN Neuronal hybrid cells (VSC4.1) were cultured with GH. The concentration ranged from 0.134 microg/ml up to 1.34 mg/ml. A cell confluency and MTT assay, cell cycle phase analysis with flow cytometry, extracellular receptor kinase (ERK) phosphorylation and mitogen activated protein kinase (MAPK) inhibitor (PD98050) assays were all performed to determine the effect on proliferation. Differentiation was evaluated by neurite outgrowth and neurofilament expression. Terminally differentiated neurons were stained by Hoechst 33342 for apoptotic nuclear fragmentation by degeneration. Poly-adenosyl ribose polymerase (PARP) expression and its cleavage products were evaluated. RESULTS Cells at concentrations between 0.134 microg/ml and 1.34 microg/ml of GH proliferated with ERK phosphorylation, which was attenuated by MAPK inhibitors. Proliferation decreased at concentrations higher than 13.4 microg/ml; however, neurite outgrowth was observed at these concentrations. Terminally differentiated cells underwent apoptosis and showed nuclear fragmentation by Hoechst 33342 staining. PARP expression was increased with caspase-3 dependent-cleaved fragment. CONCLUSIONS Our in vitro data demonstrate that GH exerts dual effects; proliferation with a specific GH dose window, or differentiation in a dose-dependent manner in cultured neuronal hybrid cells.
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Affiliation(s)
- Esther Lyuh
- Department of Preventive Medicine, Seoul National University, Esther Clinic, Seoul 110-744, Republic of Korea
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18
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Veldhuis JD, Cosma M, Erickson D, Paulo R, Mielke K, Farhy LS, Bowers CY. Tripartite control of growth hormone secretion in women during controlled estradiol repletion. J Clin Endocrinol Metab 2007; 92:2336-45. [PMID: 17405836 DOI: 10.1210/jc.2007-0043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Studies of how aging attenuates GH secretion are confounded by differences in sex-steroid milieus, abdominal visceral fat mass (AVF), and IGF-I concentrations and limited in interpretability by the use of pharmacological doses of secretagogues. HYPOTHESIS In a controlled estrogenic milieu, near-physiological secretagogue drive will unmask distinct influences of age, AVF, and IGF-I on GH secretion. LOCATION The study was conducted at an academic medical center. SUBJECTS Subjects included 10 healthy pre- (PRE) and 10 postmenopausal (POST) women. PROCEDURE In a defined estradiol (E(2)) milieu, we compared GH secretion after submaximal stimulation with GH-releasing peptide (GHRP)-2 (ghrelin analog), GHRH, and l-arginine (an inhibitor of somatostatin outflow). ANALYSIS We related GH responses to age stratum (dichotomous variable) and AVF and IGF-I concentrations (continuous variables). RESULTS In the face of comparable concentrations of E(2), testosterone, and SHBG: 1) age (P < 0.001) and secretagogue type (P < 0.001) independently determined GH secretion; 2) GH responses in POST subjects were only 26-33% of those in PRE (P < or = 0.002) across all secretagogues; 3) POST women lost the PRE order of secretagogue potency (GHRP-2 > GHRH = l-arginine); and 4) in the combined cohorts, higher AVF predicted reduced l-arginine-stimulated GH secretion (R(2) = 0.46, P = 0.0013), whereas higher IGF-I concentrations forecast increased GHRP-2 and GHRH drive (R(2) > or = 0.52, P < or = 0.013). CONCLUSION A paradigm of near-physiological secretagogue drive in an E(2)-clamped milieu unmasks tripartite deficits in peptide-signaling pathways in healthy POST, compared with PRE, women. Post hoc analyses indicate that both greater visceral adiposity and lower IGF-I concentrations mark this triple regulatory defect.
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Affiliation(s)
- Johannes D Veldhuis
- Endocrine Research Unit 9, General Clinical Research Center, Mayo Medical and Graduate Schools of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
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19
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20
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21
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Affiliation(s)
- Susan Kaweski
- Aesthetic Arts Institute, San Diego, Calif. 92123, USA.
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22
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T'Sjoen GG, De Vos S, Goemaere S, Van Pottelbergh I, Dierick M, Van Heeringen C, Kaufman JM. Sex Steroid Level, Androgen Receptor Polymorphism, and Depressive Symptoms in Healthy Elderly Men. J Am Geriatr Soc 2005; 53:636-42. [PMID: 15817010 DOI: 10.1111/j.1532-5415.2005.53212.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVES To determine the prevalence of depression in a cohort of elderly men as assessed using a 30-item Geriatric Depression Scale (GDS) score and to describe the association between this score and sex steroids, androgen receptor (AR) polymorphism, and general health status. DESIGN Observational study on the relationship between sex steroid status and health-related parameters. SETTING Community-based. PARTICIPANTS Ambulatory men (n=236 in 1997, n=192 in 2000) aged 70 and older at inclusion in 1996, interviewed in 1997 and 2000. MEASUREMENTS Serum levels of testosterone, estradiol, sex hormone binding globulin (SHBG), dehydroepiandrosterone-sulfate (DHEAS), cortisol, and the AR gene cytosine, adenine, guanine (CAG)-repeat length polymorphism were determined. Free testosterone and free estradiol were calculated. Questionnaires included GDS, 36-item Short Form, and Rapid Disability Rating Scale-2. RESULTS Median age was 75.3 years (interquartile range=73.5-78.5). A GDS score of 11 or greater was found in 30 (12.7%) men. Age and GDS score were significantly interrelated (P<.01), as were all health-assessment scores. GDS scores were not related to (free) testosterone or AR polymorphism in 1997 or 2000. In 1997 only (n=236), higher GDS scores were related to higher estradiol, free estradiol, and DHEAS levels. CONCLUSION The data did not support a role for testosterone in depression in elderly community-based men as assessed using the GDS.
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Affiliation(s)
- Guy G T'Sjoen
- Department of Endocrinology, Unit for Osteoporosis and Metabolic Bone Diseases, University Hospital Ghent, De Pintelaan 185, 9000 Ghent, Belgium.
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Payette H, Roubenoff R, Jacques PF, Dinarello CA, Wilson PWF, Abad LW, Harris T. Insulin-like growth factor-1 and interleukin 6 predict sarcopenia in very old community-living men and women: the Framingham Heart Study. J Am Geriatr Soc 2003; 51:1237-43. [PMID: 12919235 DOI: 10.1046/j.1532-5415.2003.51407.x] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVES To assess the prognostic role of the inflammatory cytokine, interleukin 6 (IL-6), and insulin-like growth factor-1 (IGF-1) in predicting 2-year changes in fat-free mass (FFM) while controlling for potential confounders. DESIGN Population-based cohort, the Framingham Heart Study, examined in 1992-93 and 1994-95. SETTING General community. PARTICIPANTS Two hundred thirty-two men and 326 women aged 72 to 92. MEASUREMENTS IGF-1 was measured using radio-immunoassay and cellular IL-6 production using non-cross-reacting radioimmunoassays. FFM was estimated using population-specific equations for predicting FFM from bioelectrical impedance analysis developed separately for men and women. RESULTS Higher IGF-1 predicted smaller loss of FFM in men than lower IGF-1 did (P=.002), after adjusting for age, baseline FFM, fat mass, and 2-year weight changes, whereas cellular IL-6 was a significant predictor of sarcopenia in women (P=.02). Weight change was a strong determinant of change in FFM in both sexes (P<.0001). CONCLUSION Predictors of sarcopenia include body composition characteristics that are common to men and women and sex-specific metabolic predictors. Sarcopenia appears to reflect a withdrawal of anabolic stimuli, such as growth hormone, in men but an increase in catabolic stimuli, such as cellular IL-6, in women.
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Affiliation(s)
- Hélène Payette
- Nutrition, Exercise Physiology, and Sarcopenia Laboratory, Tufts University, Boston, Massachusetts, USA.
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24
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Abstract
Growth hormone (GH) is classically linked with linear growth in childhood but continues to have important metabolic actions throughout life. GH deficiency in adulthood causes a distinct syndrome with significant morbidities. These include increased total and visceral fat, decreased muscle mass and aerobic capacity, affective disturbances, abnormal lipids, and increased vascular mortality, all of which are ameliorated with GH replacement. The possibility of adult GH deficiency (AGHD) should always be considered in individuals with a history of childhood GH deficiency or significant hypothalamic-pituitary damage, and the diagnosis should then be confirmed by biochemical testing. Adult GH dosing is much lower than that in pediatric practice, as appropriate for physiologic reconstitution. Hormonal side effects are minimized by stepwise dose titration. Lingering concerns remain regarding the possibility of increased cancer risk with long-term treatment, but this hazard has not been unequivocally demonstrated. Compared with AGHD, there is much less information about GH replacement in other diseases or in normal aging, or about the use of supraphysiologic GH doses to treat catabolic states. In critical illness, high-dose GH therapy has proven clearly harmful, and the balance of risks and benefits of GH administration in most adult contexts other than AGHD has not been defined.
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Affiliation(s)
- David E Cummings
- Department of Medicine, VA Puget Sound Health Care System, University of Washington, Seattle, Washington 98108, USA.
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Affiliation(s)
- O Khorram
- Department of Obstetrics and Gynecology, Harbor-UCLA Medical Center, Torrance, California 90502, USA
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Lange KH, Isaksson F, Rasmussen MH, Juul A, Bülow J, Kjaer M. GH administration and discontinuation in healthy elderly men: effects on body composition, GH-related serum markers, resting heart rate and resting oxygen uptake. Clin Endocrinol (Oxf) 2001; 55:77-86. [PMID: 11453955 DOI: 10.1046/j.1365-2265.2001.01344.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND AND OBJECTIVES GH administration results in increased lean body mass (LBM), decreased fat mass (FM) and increased energy expenditure (EE). GH therapy may therefore have potential benefits, especially in the elderly, who are known to have decreased function of the GH/IGF-I axis. Several studies have focused on effects of GH administration in the elderly in the last decade. However, very limited information is available regarding changes in body composition and EE upon GH discontinuation in the elderly. The present study therefore investigated the effects of 12 weeks of GH administration and subsequent discontinuation on body composition, resting oxygen uptake (VO2), resting heart rate (HR) and GH related serum markers in healthy elderly men. SUBJECTS AND METHODS Sixteen healthy men [age 74 +/- 1 years (mean +/- SEM), height 174.2 +/- 1.6 cm, body weight 80.7 +/- 2.6 kg, body fat 27.5 +/- 1.1%] completed the study protocol. Recombinant human GH (1.80 +/- 0.24 IU/day) was administered for 12 weeks in a single-blinded, placebo-controlled design. Body composition (dual energy X-ray absorptiometry), resting VO2 (indirect calorimetry), resting HR (telemetry) and serum IGF-I, IGF-II, IGFBP-3 and acid labile subunit (ALS) were measured at baseline, after 12 weeks of GH administration and, additionally in the GH group, 1, 2, 3, 4, 5 and 9 days after GH discontinuation. RESULTS Body weight was unchanged from baseline to 12 weeks in both groups. However, GH administration caused a decrease in FM (3.4 +/- 1.0 kg, P < 0.012), paralleled by a similar increase in LBM (3.2 +/- 0.4 kg, P < 0.0002). Resting VO2 and resting HR increased by 31 +/- 3.6% and 7.3 +/- 1.9 per minute, respectively, in the GH-group, where significant increases in serum IGF-I, IGFBP-3 and ALS also were noted. None of the above parameters changed in the placebo group. Within 2-3 days after GH discontinuation, the GH related serum markers and resting HR returned to baseline levels, whereas resting VO2 remained elevated even 9 days after GH discontinuation. In addition, GH discontinuation caused a significant decrease in body weight (1.86 +/- 0.35 kg), derived exclusively from a decrease in LBM (1.63 +/- 0.43 kg), while the decreased FM was maintained (12 weeks: 17.93 +/- 1.65 kg, +9 days: 17.74 +/- 1.62 kg). CONCLUSIONS The increases in serum IGF-I, IGFBP-3, ALS and resting heart rate induced by 12 weeks of GH administration in elderly men returned to baseline levels within 2-3 days after GH discontinuation. However, resting VO2 remained elevated for a longer period. GH administration reduced fat mass but maintained body weight by increasing lean body mass. In contrast, 9 days of GH discontinuation reduced body weight exclusively by reducing lean body mass.
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Affiliation(s)
- K H Lange
- Sports Medicine Research Unit, Bispebjerg Hospital, Bispebjerg Bakke 23, DK-2400 Copenhagen, Denmark.
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Lange KH, Isaksson F, Juul A, Rasmussen MH, Bülow J, Kjaer M. Growth hormone enhances effects of endurance training on oxidative muscle metabolism in elderly women. Am J Physiol Endocrinol Metab 2000; 279:E989-96. [PMID: 11052952 DOI: 10.1152/ajpendo.2000.279.5.e989] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study investigated whether recombinant human (rh) growth hormone (GH) combined with endurance training would have a larger effect on oxidative capacity, metabolism, and body fat than endurance training alone. Sixteen healthy, elderly women, aged 75 yr, performed closely monitored endurance training on a cycle ergometer over 12 wk. rhGH was given in a randomized, double-blinded, placebo-controlled design in addition to the training program. GH administration resulted in a doubling of serum insulin-like growth factor I levels. With endurance training, peak oxygen uptake increased by approximately 18% in both groups, whereas the marked increase in muscle citrate synthase activity was 50% larger in the GH group compared with the placebo group. In addition, only the GH group revealed an increase in muscle L-3-hydroxyacyl-CoA dehydrogenase activity. Body weight remained unchanged in both groups, but the GH group showed significant changes in body composition with a decrease in fat mass and an increase in lean body mass. Twenty-four-hour indirect calorimetry performed in four subjects showed a marked increase in energy expenditure with increased relative and absolute fat combustion in the two subjects receiving rhGH. In conclusion, rhGH adds to the effects of endurance training on muscle oxidative enzymes and causes a reduction in body fat in elderly women.
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Affiliation(s)
- K H Lange
- Sports Medicine Research Unit, Bispebjerg Hospital, DK-2400 Copenhagen, Denmark.
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Janssens H, Vanderschueren DM. Endocrinological aspects of aging in men: is hormone replacement of benefit? Eur J Obstet Gynecol Reprod Biol 2000; 92:7-12. [PMID: 10986428 DOI: 10.1016/s0301-2115(00)00420-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Age-related decreases of serum testosterone (total, free and bioavailable), DHEA, DHEA-S, growth hormone (GH) and IGF-I are well established in elderly healthy men. Although substantial, the decrease of these hormones is small compared to the estrogen changes observed in postmenopausal women. Elderly men also loose bone and muscle, gain fat and have less sexual appetite. Therefore, the assumption that hormonal therapy is a potential 'fountain of youth' appears logical. At present, however, the effects of replacement of testosterone, DHEA and GH in healthy elderly men have been studied in only a few randomised placebo-controlled trials. These studies were small and of short duration. Although some significant overall effects of either androgen or GH replacement on body composition (less fat and more muscle) were found, the effects of such therapy on muscle strength, on metabolic and sexual function and on skeletal homeostasis have been less consistent. Also, the safety of such therapy should be better documented. Moreover, data obtained in healthy elderly men cannot be transposed to non-healthy elderly men. In conclusion, more scientific work is needed before general replacement of the 'falling hormones' should be regarded as beneficial for elderly men.
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Affiliation(s)
- H Janssens
- Department of Endocrinology, UZ Gasthuisberg, Herestraat 49, B-3000, Leuven, Belgium
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Sauerwein H, Breier BH, Gallaher BW, Götz C, Küfner G, Montag T, Vickers M, Schallenberger E. Growth hormone treatment of breeding bulls used for artificial insemination improves fertilization rates. Domest Anim Endocrinol 2000; 18:145-58. [PMID: 10701771 DOI: 10.1016/s0739-7240(99)00070-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To evaluate new therapeutical concepts for male subfertility, we tested the effects of exogenous recombinant bovine growth hormone (rbGH) on various endocrine and metabolic parameters both in blood and in seminal plasma of bulls. Sperm quality was assessed morphometrically and by monitoring the number of successful artificial inseminations (AIs) defined as non-return rates (NRR). Aliquots of 450 semen samples were used from each bull and each experimental period (4 wk before, 14 weeks during and 6 wk after treatment). Six out of ten sires (average age 8.4 years) were treated every two weeks with 640-mg depot formulated rbGH (Eli Lilly). Four bulls received vehicle only. Blood plasma bGH, IGF-I, insulin and glucose concentrations were increased with rbGH treatment. In seminal plasma there was no effect of rbGH treatment on fructose and citrate or on testosterone concentrations. With one exception, rbGH-treated bulls had greater IGFBP-3 concentrations in seminal plasma. Motility of spermatozoa after freezing and thawing was increased compared with pretreatment rates. Most interestingly, the number of successful AIs was increased by an average of 6.0% NRR when ejaculates from rbGH-treated bulls were used.
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Affiliation(s)
- H Sauerwein
- Institute of Physiology, Research Centre for Milk and Food Weihenstephan, Technical University Munich, Weihenstephan, Germany.
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Abstract
According to the somatomedin model, growth hormone (GH)-dependent hepatic synthesis is responsible for maintaining circulating insulin-like growth factor (IGF)-I levels. On the other hand, the local autocrine/paracrine IGF-I expression in peripheral tissue is generally GH-independent and reflects the effects of various and tissue-specific trophic hormones. Circulating IGF-I levels undergo important age-related variations increasing at puberty and decreasing, thereafter, to low levels in the elderly. Low IGF-I levels in the elderly mainly reflect impaired somatotroph secretion but the decline in gonadal sex steroid levels, some protein and micronutrients malnutrition as well as age-dependent variations in IGF-binding proteins may also play a role in the age-related decrease in IGF-I activity. This, in turn, partially accounts for age-related changes in bones, muscles, cardiovascular system, central nervous system and the immune system. However, it is currently unclear whether treatment with exogenous IGF-I can retard or reverse age-related changes in body structure and function.
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Affiliation(s)
- E Arvat
- Division of Endocrinology, Department of Internal Medicine, University of Turin, Italy
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de Jong N, Chin A Paw MJ, de Groot LC, de Graaf C, Kok FJ, van Staveren WA. Functional biochemical and nutrient indices in frail elderly people are partly affected by dietary supplements but not by exercise. J Nutr 1999; 129:2028-36. [PMID: 10539780 DOI: 10.1093/jn/129.11.2028] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A decline in dietary intake due to inactivity and, consequently, development of a suboptimal nutritional status is a major problem in frail elderly people. However, benefits of micronutrient supplementation, all-round physical exercise or a combination of both on functional biochemical and hematologic indicators of nutritional and health status in frail elderly subjects have not been tested thoroughly. A 17-wk randomized controlled trial was performed in 145 free-living frail elderly people (43 men, 102 women, mean age, 78 +/- 5.7 y). Based on a 2 x 2 factorial design, subjects were assigned to one of the following: 1) nutrient-dense foods, 2) exercise, 3) both (1) and (2) or 4) a control group. Foods were enriched with micronutrients, frequently characterized as deficient [25-100% of the recommended daily allowance (RDA)] in elderly people. Exercises focused on skill training, including strength, endurance, coordination and flexibility. Dietary intake, blood vitamin levels and nutritional and health indicators, including (pre)albumin, ferritin, transferrin, C-reactive protein, hemoglobin and lymphocytes were measured. At baseline, 28% of the total population had an energy intake below 6.3 MJ, up to a maximum of 93% having vitamin intakes below two thirds of the Dutch RDA. Individual deficiencies in blood at baseline ranged from 3% for erythrocyte glutathione reductase-alpha to 39% for 25-hydroxy vitamin D and 42% for vitamin B-12. These were corrected after 17 wk in the two groups receiving the nutrient-dense foods, whereas no significant changes were observed in the control or exercise group. Biochemical and hematologic indicators at baseline were within the reference ranges (mean albumin, 46 g/L; prealbumin, 0.25 g/L; hemoglobin, 8.6 mmol/L) and were not affected by any of the interventions. The long-term protective effects of nutrient supplementation and exercise, by maintaining optimal nutrient levels and thereby reducing the initial chance of developing critical biochemical values, require further investigation. Other indicative functional variables for suboptimal nutritional status, in addition to those currently selected, should also be explored.
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Affiliation(s)
- N de Jong
- Division of Human Nutrition and Epidemiology, Wageningen Agricultural University, Dreÿenlaan 6703 HA Wageningen, The Netherlands
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