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Abstract
The foundation of bone health is established in utero. Bone accrual starts from the developing fetus and continues throughout childhood and adolescence. This process is crucial to achieve peak bone mass. Understanding factors that influence bone accrual before attainment of peak bone mass is thus critical to improve bone health and prevent osteoporosis, thereby reducing the burden of osteoporotic fractures in older women. In this review, we broadly outline factors influencing peak bone mass from pregnancy to infancy, childhood and adolescence with potential diseases and medications that may affect the optimum trajectory to maximizing bone health. It is estimated that a 10% increase in peak bone mass will delay the onset of osteoporosis by 13 years in a woman.
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Affiliation(s)
- R F Vasanwala
- KK Women's and Children's Hospital, Singapore, Singapore
| | - L Gani
- Changi General Hospital, Singapore, Singapore
| | - S B Ang
- KK Women's and Children's Hospital, Singapore, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Lee Kong Chian School of Medicine, Singapore, Singapore
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2
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Insulin-Like Growth Factor-II and Ischemic Stroke-A Prospective Observational Study. Life (Basel) 2021; 11:life11060499. [PMID: 34072372 PMCID: PMC8230196 DOI: 10.3390/life11060499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 11/25/2022] Open
Abstract
Insulin-like growth factor-II (IGF-II) regulates prenatal brain development, but the role in adult brain function and injury is unclear. Here, we determined whether serum levels of IGF-II (s-IGF-II) are associated with mortality and functional outcome after ischemic stroke (IS). The study population comprised ischemic stroke cases (n = 492) and controls (n = 514) from the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS). Functional outcome was evaluated after 3 months and 2 years using the modified Rankin Scale (mRS), and additionally, survival was followed at a minimum of 7 years or until death. S-IGF-II levels were higher in IS cases both in the acute phase and at 3-month follow-up compared to controls (p < 0.05 and p < 0.01, respectively). The lowest quintile of acute s-IGF-II was, compared to the four higher quintiles, associated with an increased risk of post-stroke mortality (median follow-up 10.6 years, crude hazard ratio (HR) 2.34, 95% confidence interval (CI) 1.56–3.49, and fully adjusted HR 1.64, 95% CI 1.02–2.61). In contrast, crude associations with poor functional outcome (mRS 3–6) lost significance after full adjustment for covariates. In conclusion, s-IGF-II was higher in IS cases than in controls, and low acute s-IGF-II was an independent risk marker of increased mortality.
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Strasser B, Pesta D, Rittweger J, Burtscher J, Burtscher M. Nutrition for Older Athletes: Focus on Sex-Differences. Nutrients 2021; 13:nu13051409. [PMID: 33922108 PMCID: PMC8143537 DOI: 10.3390/nu13051409] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 04/08/2021] [Accepted: 04/12/2021] [Indexed: 12/13/2022] Open
Abstract
Regular physical exercise and a healthy diet are major determinants of a healthy lifespan. Although aging is associated with declining endurance performance and muscle function, these components can favorably be modified by regular physical activity and especially by exercise training at all ages in both sexes. In addition, age-related changes in body composition and metabolism, which affect even highly trained masters athletes, can in part be compensated for by higher exercise metabolic efficiency in active individuals. Accordingly, masters athletes are often considered as a role model for healthy aging and their physical capacities are an impressive example of what is possible in aging individuals. In the present review, we first discuss physiological changes, performance and trainability of older athletes with a focus on sex differences. Second, we describe the most important hormonal alterations occurring during aging pertaining regulation of appetite, glucose homeostasis and energy expenditure and the modulatory role of exercise training. The third part highlights nutritional aspects that may support health and physical performance for older athletes. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low bone and muscle mass and a higher demand for specific nutrients (e.g., vitamin D and probiotics) that may reduce the infection burden in masters athletes. Fourth, we present important research findings on the association between exercise, nutrition and the microbiota, which represents a rapidly developing field in sports nutrition.
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Affiliation(s)
- Barbara Strasser
- Medical Faculty, Sigmund Freud Private University, A-1020 Vienna, Austria
- Correspondence: ; Tel.: +43-(0)1-798-40-98
| | - Dominik Pesta
- Institute of Aerospace Medicine, German Aerospace Center (DLR), D-51147 Cologne, Germany; (D.P.); (J.R.)
- Centre for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, D-50931 Cologne, Germany
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), D-50931 Cologne, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine University Düsseldorf, D-40225 Düsseldorf, Germany
- German Center for Diabetes Research (DZD e.V.), D-85764 Neuherberg, Germany
- Department of Sport Science, University of Innsbruck, A-6020 Innsbruck, Austria;
| | - Jörn Rittweger
- Institute of Aerospace Medicine, German Aerospace Center (DLR), D-51147 Cologne, Germany; (D.P.); (J.R.)
| | - Johannes Burtscher
- Department of Biomedical Sciences, University of Lausanne, CH-1015 Lausanne, Switzerland;
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, A-6020 Innsbruck, Austria;
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Distinct signaling by insulin and IGF-1 receptors and their extra- and intracellular domains. Proc Natl Acad Sci U S A 2021; 118:2019474118. [PMID: 33879610 DOI: 10.1073/pnas.2019474118] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Insulin and insulin-like growth factor 1 (IGF-1) receptors share many downstream signaling pathways but have unique biological effects. To define the molecular signals contributing to these distinct activities, we performed global phosphoproteomics on cells expressing either insulin receptor (IR), IGF-1 receptor (IGF1R), or chimeric IR-IGF1R receptors. We show that IR preferentially stimulates phosphorylations associated with mammalian target of rapamycin complex 1 (mTORC1) and Akt pathways, whereas IGF1R preferentially stimulates phosphorylations on proteins associated with the Ras homolog family of guanosine triphosphate hydrolases (Rho GTPases), and cell cycle progression. There were also major differences in the phosphoproteome between cells expressing IR versus IGF1R in the unstimulated state, including phosphorylation of proteins involved in membrane trafficking, chromatin remodeling, and cell cycle. In cells expressing chimeric IR-IGF1R receptors, these differences in signaling could be mapped to contributions of both the extra- and intracellular domains of these receptors. Thus, despite their high homology, IR and IGF1R preferentially regulate distinct networks of phosphorylation in both the basal and stimulated states, allowing for the unique effects of these hormones on organismal function.
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Eriksen AZ, Eliasen R, Oswald J, Kempen PJ, Melander F, Andresen TL, Young M, Baranov P, Urquhart AJ. Multifarious Biologic Loaded Liposomes that Stimulate the Mammalian Target of Rapamycin Signaling Pathway Show Retina Neuroprotection after Retina Damage. ACS NANO 2018; 12:7497-7508. [PMID: 30004669 PMCID: PMC6117751 DOI: 10.1021/acsnano.8b00596] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 07/13/2018] [Indexed: 05/08/2023]
Abstract
A common event in optic neuropathies is the loss of axons and death of retinal ganglion cells (RGCs) resulting in irreversible blindness. Mammalian target of rapamycin (mTOR) signaling pathway agonists have been shown to foster axon regeneration and RGC survival in animal models of optic nerve damage. However, many challenges remain in developing therapies that exploit cell growth and tissue remodeling including (i) activating/inhibiting cell pathways synergistically, (ii) avoiding tumorigenesis, and (iii) ensuring appropriate physiological tissue function. These challenges are further exacerbated by the need to overcome ocular physiological barriers and clearance mechanisms. Here we present liposomes loaded with multiple mTOR pathway stimulating biologics designed to enhance neuroprotection after retina damage. Liposomes were loaded with ciliary neurotrophic factor, insulin-like growth factor 1, a lipopeptide N-fragment osteopontin mimic, and lipopeptide phosphatase tension homologue inhibitors for either the ATP domain or the c-terminal tail. In a mouse model of N-methyl-d-aspartic acid induced RGC death, a single intravitreal administration of liposomes reduced both RGC death and loss of retina electrophysiological function. Furthermore, combining liposomes with transplantation of induced pluripotent stem cell derived RGCs led to an improved electrophysiological outcome in mice. The results presented here show that liposomes carrying multiple signaling pathway modulators can facilitate neuroprotection and transplant electrophysiological outcome.
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Affiliation(s)
- Anne Z. Eriksen
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Rasmus Eliasen
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Julia Oswald
- Schepens
Eye Research Institute, Massachusetts Eye and Ear, 20 Staniford Street, Boston, Massachusetts 02114, United States
| | - Paul J. Kempen
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Fredrik Melander
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Thomas L. Andresen
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
| | - Michael Young
- Schepens
Eye Research Institute, Massachusetts Eye and Ear, 20 Staniford Street, Boston, Massachusetts 02114, United States
| | - Petr Baranov
- Schepens
Eye Research Institute, Massachusetts Eye and Ear, 20 Staniford Street, Boston, Massachusetts 02114, United States
| | - Andrew J. Urquhart
- DTU
Nanotech, Department of Micro- and Nanotechnology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
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Causes of low peak bone mass in women. Maturitas 2017; 111:61-68. [PMID: 29673833 DOI: 10.1016/j.maturitas.2017.12.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 12/09/2017] [Accepted: 12/12/2017] [Indexed: 12/18/2022]
Abstract
Peak bone mass is the maximum bone mass that accrues during growth and development. Consolidation of peak bone mass normally occurs during early adulthood. Low peak bone mass results from failure to achieve peak bone mass genetic potential, primarily due to bone loss caused by a variety of conditions or processes occurring at younger ages than usual. Recognized causes of low peak bone mass include genetic causes, endocrine disorders, nutritional disorders, chronic diseases of childhood or adolescence, medications, and idiopathic factors.
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Chang YM, Chang HH, Tsai CC, Lin HJ, Ho TJ, Ye CX, Chiu PL, Chen YS, Chen RJ, Huang CY, Lin CC. Alpinia oxyphylla Miq. fruit extract activates IGFR-PI3K/Akt signaling to induce Schwann cell proliferation and sciatic nerve regeneration. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017; 17:184. [PMID: 28359314 PMCID: PMC5374583 DOI: 10.1186/s12906-017-1695-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 03/17/2017] [Indexed: 11/10/2022]
Abstract
BACKGROUND It is known that the medicinal herb Alpinia oxyphylla Miq. is widely used as a remedy for diarrhea as well as the symptoms accompanying hypertension and cerebrovascular disorders. Moreover, it has also been reported that Alpinia oxyphylla Miq. has beneficial effects on anti-senescence and neuro-protection. This study focuses on the molecular mechanisms by which the Alpinia oxyphylla Miq. fruits promote neuron regeneration. METHODS A piece of silicone rubber was guided across a 15 mm gap in the sciatic nerve of a rat. This nerve gap was then filled with various doses of Alpinia oxyphylla Miq. fruits to assess their regenerative effect on damaged nerves. Further, we investigated the role of Alpinia oxyphylla Miq. fruits in RSC96 Schwann cell proliferation. RESULTS Our current results showed that treatment with the extract of Alpinia oxyphylla Miq. fruits triggers the phosphorylated insulin-like growth factor-1 receptor- phosphatidylinositol 3-kinase/serine-threonine kinase pathway, and up-regulated the proliferating cell nuclear antigen in a dose-dependent manner. Cell cycle analysis on RSC96 Schwann cells showed that, after exposure to Alpinia oxyphylla Miq. fruit extract, the transition from the first gap phase to the synthesis phase occurs in 12-18 h. The expression of the cell cycle regulatory proteins cyclin D1, cyclin E and cyclin A increased in a dose-dependent manner. Transfection with a small interfering RNA blocked the expression of phosphatidylinositol 3-kinase and induced down-regulation both on the mRNA and protein levels, which resulted in a reduction of the expression of the survival factor B-cell lymphoma 2. CONCLUSION We provide positive results that demonstrate that Alpinia oxyphylla Miq. fruits facilitate the survival and proliferation of RSC96 cells via insulin-like growth factor-1 signaling.
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Lopez-Espinosa MJ, Mondal D, Armstrong BG, Eskenazi B, Fletcher T. Perfluoroalkyl Substances, Sex Hormones, and Insulin-like Growth Factor-1 at 6-9 Years of Age: A Cross-Sectional Analysis within the C8 Health Project. ENVIRONMENTAL HEALTH PERSPECTIVES 2016; 124:1269-75. [PMID: 26794451 PMCID: PMC4977043 DOI: 10.1289/ehp.1509869] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 12/18/2015] [Indexed: 05/18/2023]
Abstract
BACKGROUND Exposure to some perfluoroalkyl substances (PFAS), such as perfluorohexane sulfonate (PFHxS), perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and perfluorononanoic acid (PFNA), may alter levels of sex hormones and insulin-like growth factor-1 (IGF-1) in animals. Human studies on this topic are scarce, and none have been conducted in young children. OBJECTIVES We investigated the relationship between levels of PFAS and estradiol, total testosterone, and IGF-1 in 2,292 children (6-9 years of age) from the C8 Health Project who lived near a chemical plant in the Mid-Ohio Valley (USA) with local contamination from PFOA. METHODS Serum samples were collected in 2005-2006 and analyzed for PFAS, sex hormones, and IGF-1. Results from regression models were expressed as the adjusted percentage difference (95% CI) per sex-specific interquartile range (IQR) increment of each PFAS serum concentration. Analyses by PFAS quartiles were also conducted. RESULTS Median concentrations of PFHxS, PFOA, PFOS, and PFNA were 8, 35, 22, and 1.7 ng/mL in boys and 7, 30, 21, and 1.7 ng/mL in girls. In boys, PFOA concentrations were significantly associated with testosterone levels (-4.9%; 95% CI: -8.7, -0.8%); PFOS with estradiol (-4.0%; 95% CI: -7.7, -0.1%), testosterone (-5.8%; 95% CI: -9.4, -2.0%), and IGF-1 (-5.9%; 95% CI: -8.3, -3.3%); and PFNA with IGF-1 (-3.5%; 95% CI: -6.0, -1.0%). In girls, significant associations were found between PFOS and testosterone (-6.6%; 95% CI: -10.1, -2.8%) and IGF-1 (-5.6%; -8.2, -2.9%); and PFNA and IGF-1 (-3.8%; 95% CI: -6.4, -1.2%). In both sexes, the magnitudes of the associations decreased monotonically across quartiles for both testosterone and IGF-1 in relation to PFOS, and for IGF-1 and PFNA in girls. CONCLUSIONS To our knowledge, this is the first study suggesting that PFAS are associated with lower levels of IGF-1 and sex hormones in young children. CITATION Lopez-Espinosa MJ, Mondal D, Armstrong BG, Eskenazi B, Fletcher T. 2016. Perfluoroalkyl substances, sex hormones, and insulin-like growth factor-1 at 6-9 years of age: a cross-sectional analysis within the C8 Health Project. Environ Health Perspect 124:1269-1275; http://dx.doi.org/10.1289/ehp.1509869.
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Affiliation(s)
- Maria-Jose Lopez-Espinosa
- Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Epidemiology and Environmental Health Joint Research Unit, FISABIO (Foundation for the Promotion of Health and Biomedical Research in the Valencian Region)–Universitat Jaume I–Universitat de València, Valencia, Spain
- Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Madrid, Spain
- Address correspondence to M.-J. Lopez-Espinosa, Foundation for the Promotion of Health and Biomedical Research in the Valencian Region, FISABIO-Public Health, Valencia, Spain, Avda Catalunya 21, 46020 Valencia, Spain. Telephone: (34) 961925943. E-mail:
| | - Debapriya Mondal
- Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, London, United Kingdom
- School of Environment and Life Sciences, University of Salford, The Crescent, Salford, United Kingdom
| | - Ben G. Armstrong
- Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Brenda Eskenazi
- Center for Environmental Research and Children’s Health (CERCH), School of Public Health, University of California, Berkeley, Berkeley, California, USA
| | - Tony Fletcher
- Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Soliman AT, Sanctis VD, Elalaily R, Yassin M. Insulin-like growth factor- I and factors affecting it in thalassemia major. Indian J Endocrinol Metab 2015; 19:245-51. [PMID: 25729686 PMCID: PMC4319264 DOI: 10.4103/2230-8210.131750] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Despite improvement of blood transfusion regimens and iron chelation therapy growth and maturational delay, cardiomyopathy, endocrinopathies and osteoporosis still occur in good number of thalassemic patients. Decreased IGF-1 secretion occurs in the majority of the thalassemic patients particularly those with growth and pubertal delay. Many factors contribute to this decreased synthesis of IGF-I including disturbed growth hormone (GH) - insulin-like growth factor - I (IGF-I) axis. The possible factors contributing to low IGF-I synthesis in thalassemia and the possible interaction between low IGF-I secretion and the occurrence of these complications is discussed in this mini-review. Improvement of IGF-I secretion in thalassemic patients should be intended to improve linear growth and bone mineral accretion in thalassemic patients. This can be attained through adequate correction of anemia and proper chelation, nutritional supplementation (increasing caloric intake), correction of vitamin D and zinc deficiencies, induction of puberty and correction of hypogonadism at the proper time and treating GH deficiency. This review paper provides a summary of the current state of knowledge regarding IGF-I and factors affecting it in patients with thalassaemia major (TM). Search on PubMed and reference lists of articles with the term 'IGF-I, GH, growth, thalassemia, thyroxine, anemia, vitamin D, and zinc' was carried out. A hundred and forty-eight articles were found and used in the write up and the data analyzed was included in this report.
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Affiliation(s)
- Ashraf T. Soliman
- Department of Pediatric, Pediatric Endocrinology Division, Alamal Hospital, Hamad Medical Center, Qatar
| | - Vincenzo De Sanctis
- Department of Pediatric and Adolescent Outpatient Clinic, Quisisana Hospital, Ferrara, Italy
| | - Rania Elalaily
- Department of Family Medicine, Primary Health Care, Doha, Qatar
| | - Mohamed Yassin
- Department of Hematology and Oncology, Alamal Hospital, Hamad Medical Center, Qatar
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Abstract
IGF-I (insulin-like growth factor-I) is a peptide hormone, produced predominantly by the liver in response to pituitary GH (growth hormone), which is involved in a wide variety of physiological processes. It acts in an endocrine, paracrine and autocrine manner to promote growth. The production of IGF-I signals the availability of nutrients needed for its anabolic actions. Recently, there has been growing interest in its role in health and disease. IGF-I has long been known to be regulated by nutrition and dysregulated in states of under- and over-nutrition, its serum concentrations falling in malnutrition and responding promptly to refeeding. This has led to interest in its utility as a nutritional biomarker. A considerable evidence base supports utility for measurement of IGF-I in nutritional contexts. Its concentration may be valuable in providing information on nutritional status, prognosis and in monitoring nutritional support. However, it is insufficiently specific for use as a screening test for under nutrition as its serum concentration is influenced by many factors other than nutritional status, notably the APR (acute-phase response) and endocrine conditions. Concentrations should be interpreted along with clinical findings and the results of other investigations such as CRP (C-reactive protein). More recently, there has been interest in free IGF-I which holds promise as a nutritional marker. The present review covers nutritional regulation of IGF-I and its dysregulation in disease, then goes on to review recent studies supporting its utility as a nutritional marker in clinical contexts. Although not currently recommended by clinical guidelines, it is likely that, in time, measurement of IGF-I will become a routine part of nutritional assessment in a number of these contexts.
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Chae YK, Hu MI, Katz RL, Chavez-MacGregor M, Haluska P, Meric-Bernstam F, Gonzalez-Angulo AM, Melhem-Bertrandt A. Two birds with one stone: octreotide treatment for acromegaly and breast cancer. J Clin Oncol 2013; 31:e398-400. [PMID: 23796991 DOI: 10.1200/jco.2012.46.6383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Young Kwang Chae
- Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Unit 1354, Houston, TX 77030, USA
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Livingstone C. The insulin-like growth factor system and nutritional assessment. SCIENTIFICA 2012; 2012:768731. [PMID: 24278739 PMCID: PMC3820641 DOI: 10.6064/2012/768731] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 07/05/2012] [Indexed: 06/02/2023]
Abstract
Over recent years there has been considerable interest in the role of the insulin-like growth factor (IGF) system in health and disease. It has long been known to be dysregulated in states of under- and overnutrition, serum IGF-I levels falling in malnourished patients and responding promptly to nutritional support. More recently, other proteins in this system have been observed to be dysregulated in both malnutrition and obesity. Currently no biochemical marker is sufficiently specific for use in screening for malnutrition, but levels may be valuable in providing information on nutritional status and in monitoring of nutritional support. All have limitations as nutritional markers in that their serum levels are influenced by factors other than nutritional status, most importantly the acute phase response (APR). Levels should be interpreted along with clinical findings and the results of other investigations such as C-reactive protein (CRP). This paper reviews data supporting the use of proteins of the IGF system as nutritional markers.
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Affiliation(s)
- Callum Livingstone
- Peptide Hormones Supraregional Assay Service (SAS), Clinical Biochemistry Department, Royal Surrey County Hospital, Guildford, Surrey GU2 7XX, UK
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, Surrey GU2 5XH, UK
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Chang YM, Chi WY, Lai TY, Chen YS, Tsai FJ, Tsai CH, Kuo WW, Cheng YC, Lin CC, Huang CY. Dilong: role in peripheral nerve regeneration. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 2011:380809. [PMID: 21799677 PMCID: PMC3136393 DOI: 10.1093/ecam/neq079] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Accepted: 05/25/2010] [Indexed: 01/18/2023]
Abstract
Dilong, also known as earthworm, has been widely used in traditional Chinese medicine (TCM) for thousands of years. Schwann cell migration and proliferation are critical for the regeneration of injured nerves and Schwann cells provide an essentially supportive role for neuron regeneration. However, the molecular mechanisms of migration and proliferation induced by dilongs in Schwann cells remain unclear. Here, we discuss the molecular mechanisms that includes (i) migration signaling, MAPKs (mitogen-activated protein kinases), mediated PAs and MMP2/9 pathway; (ii) survival and proliferative signaling, IGF-I (insulin-like growth factor-I)-mediated PI3K/Akt pathways and (iii) cell cycle regulation. Dilong stimulate RSC96 cell proliferation and migration. It can induce phosphorylation of ERK1/2 and p38, but not JNK, and activate the downstream signaling expression of PAs (plasminogen activators) and MMPs (matrix metalloproteinases) in a time-dependent manner. In addition, Dilong stimulated ERK1/2 and p38 phosphorylation was attenuated by pretreatment with chemical inhibitors (U0126 and SB203580), and small interfering ERK1/2 and p38 RNA, resulting in migration and uPA-related signal pathway inhibition. Dilong also induces the phosphorylation of IGF-I-mediated PI3K/Akt pathway, activates protein expression of PCNA (proliferating cell nuclear antigen) and cell cycle regulatory proteins (cyclin D1, cyclin E and cyclin A) in a time-dependent manner. In addition, it accelerates G1-phase progression with earlier S-phase entry and significant numbers of cells entered the S-phase. The siRNA-mediated knockdown of PI3K that significantly reduces PI3K protein expression levels, resulting in Bcl2 survival factor reduction, revealing a marked blockage of G1 to S transition in proliferating cells. These results reveal the unknown RSC96 cell migration and proliferation mechanism induced by dilong, which find use as a new medicine for nerve regeneration.
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Affiliation(s)
- Yung-Ming Chang
- School of Chinese Medicine, China Medical University, Taichung, Taiwan
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Chang YM, Kuo WH, Lai TY, Shih YT, Tsai FJ, Tsai CH, Shu WT, Chen YY, Chen YS, Kuo WW, Huang CY. RSC96 Schwann Cell Proliferation and Survival Induced by Dilong through PI3K/Akt Signaling Mediated by IGF-I. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 2011:216148. [PMID: 20040524 PMCID: PMC3135880 DOI: 10.1093/ecam/nep216] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 11/19/2009] [Indexed: 12/31/2022]
Abstract
Schwann cell proliferation is critical for the regeneration of injured nerves. Dilongs are widely used in Chinese herbal medicine to remove stasis and stimulate wound-healing functions. Exactly how this Chinese herbal medicine promotes tissue survival remains unclear. The aim of the present study was to investigate the molecular mechanisms by which Dilong promote neuron regeneration. Our results show that treatment with extract of Dilong induces the phosphorylation of the insulin-like growth factor-I (IGF-I)-mediated phosphatidylinositol 3-kinase/serine-threonine kinase (PI3K/Akt) pathway, and activates protein expression of cell nuclear antigen (PCNA) in a time-dependent manner. Cell cycle analysis showed that G1 transits into the S phase in 12–16 h, and S transits into the G2 phase 20 h after exposure to earthworm extract. Strong expression of cyclin D1, cyclin E and cyclin A occurs in a time-dependent manner. Small interfering RNA (siRNA)-mediated knockdown of PI3K significantly reduced PI3K protein expression levels, resulting in Bcl2 survival factor reduction and a marked blockage of G1 to S transition in proliferating cells. These results demonstrate that Dilong promotes the proliferation and survival of RSC96 cells via IGF-I signaling. The mechanism is mainly dependent on the PI3K protein.
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Affiliation(s)
- Yung-Ming Chang
- Graduate Institute of Chinese Medical Science and Institute of Basic Medical Science, China Medical University, No 91, Hsueh-Shih Road, Taichung 404, Taiwan
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Chen HT, Tsai YL, Chen YS, Jong GP, Chen WK, Wang HL, Tsai FJ, Tsai CH, Lai TY, Tzang BS, Huang CY, Lu CY. Dangshen (Codonopsis pilosula) activates IGF-I and FGF-2 pathways to induce proliferation and migration effects in RSC96 Schwann cells. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2010; 38:359-72. [PMID: 20387231 DOI: 10.1142/s0192415x10007907] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study evaluates the proliferative and migrative effects of dangshen on RSC96, Schwann cells. We investigated the molecular signaling pathways, which include: (1) survival signaling, IGFs-IGFIR-Akt-Bcl2 and proliferative signaling, cell cycle factors and MAPK pathways. (2) migrate and anti-scar signaling, FGF-2-uPA-MMPs. After treatment with different concentrations (20 microg/ml, 40 microg/ml, 60 microg/ml, 80 microg/ml, and 100 microg/ml) of dangshen. We observed a dose dependent proliferative effect using PCNA Western blotting assay, MTT assay and the wound healing test. We also found that dangshen stimulates the protein expressions of IGF-I pathway regulators, cell cycle controlling proteins and excites the MAPK signaling pathway regulators ERK and P38. Dangshen even stimulates the FGF-2-uPA-MMP 9 migration pathway in RSC 96 Schwann cells. Using MAPK chemical inhibitors, U0126, SB203580, and SP600125, the proliferative effects of dangshen on RSC 96 cells were identified to be ERK- and P38- dependent. Based on these results, applying an appropriate dose of dangshen with biomedical materials would be a potential approach for enhancing neuron regeneration.
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Affiliation(s)
- Hsien-Tung Chen
- Graduate Institute of Chinese Medical Science, China Medical University, Taichung, Taiwan
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Lu MC, Lai TY, Hwang JM, Chen HT, Chang SH, Tsai FJ, Wang HL, Lin CC, Kuo WW, Huang CY. Proliferation- and migration-enhancing effects of ginseng and ginsenoside Rg1 through IGF-I- and FGF-2-signaling pathways on RSC96 Schwann cells. Cell Biochem Funct 2009; 27:186-92. [PMID: 19326380 DOI: 10.1002/cbf.1554] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of the present study is to evaluate the proliferation- and migration-enhancing effects of ginseng and its component, ginsenoside (Rg1) on RSC96 Schwann cells. We investigated the molecular signaling pathways, which include: (1) survival signaling, IGFs-IGFIR-Akt-Bcl2 and proliferative signaling, cell cycle factors and mitogen-activated protein kinase (MAPK) pathways, (2) migrating and anti-scar signaling, FGF-2-uPA-MMPs.We treated RSC96 cells with different concentrations (100, 200, 300, 400, 500 microg ml(-1)) of ginseng and its constituent, Rg1 (5, 10, 15, 20, 25 microg ml(-1)). We observed a proliferative effect in a dose-dependent manner by PCNA western blotting assay, MTT assay, and wound healing test. Furthermore, we also found in the results of western blotting assay, ginseng and Rg1 enhance protein expression of IGF-I pathway regulators, cell cycle controlling proteins, and MAPK signaling pathways to promote the cell proliferation. In addition, ginseng and Rg1 also stimulated the FGF-2-uPA-MMP 9 migrating pathway to enhance the migration of RSC96 Schwann cells. Using MAPK chemical inhibitors, U0126, SB203580, and SP600125, the proliferative effects of ginseng and Rg1 on RSC96 cells were identified to be MAPK signaling-dependent. On the basis of the results, applying appropriate doses of ginseng and Rg1 with biomedical materials would be a potential approach for enhancing neuron regeneration.
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Affiliation(s)
- Ming-Chin Lu
- School of Post-Baccalaureate Chinese Medicine, China Medical University, Taichung, Taiwan
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Lavis VR, Picolos MK, Willerson JT. Endocrine Disorders and the Heart. CARDIOVASCULAR MEDICINE 2007. [DOI: 10.1007/978-1-84628-715-2_111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Zadik Z, Sinai T, Borondukov E, Zung A, Yaniv I, Reifen R. Longitudinal monitoring of bone accretion measured by quantitative multi-site ultrasound (QUS) of bones in patients with delayed puberty (a pilot study). Osteoporos Int 2005; 16:1036-41. [PMID: 15616757 DOI: 10.1007/s00198-004-1795-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2004] [Accepted: 10/07/2004] [Indexed: 11/25/2022]
Abstract
OBJECTIVE to compare the effect of anabolic agents on bone accretion in boys with constitutional delay of puberty (CGDP). RATIONALE it has been suggested that an appropriate timing of puberty is necessary for normal bone mineral density (BMD) acquisition. Proper bone development during childhood is the key factor in achieving higher peak bone mass during middle age, which may not be achievable in CGDP children, and thereby osteoporosis may appear at an earlier age then expected. PATIENTS AND METHODS 45 boys with CGDP aged 14-16 years were monitored longitudinally, every 3 months over 12 months with Sunlight Omnisense, a quantitative ultrasound device (Tel Aviv, Israel). The apparatus is a multi-site bone sonometer that obtains axial Speed of Sound (SOS). Based on a reference database obtained on n=1,085 (490 boys) 0-18 years, a normative curve was determined. Fifteen (14-16 years old) of the CGDP patients were treated with I.M. testovirone depot 100 mg monthly for 6 months, 15 (14-16 years old) were treated with oxandrolone 5 mg/m(2) daily for 6 months, and 15 (14-16 years old) were in an observation group. RESULTS whereas the quantitative ultrasound (QUS) Z-score had shown some increase over time in CGDP-treated patients, an increase was found in tibia Z-score from -0.5(-0.64, -0.36) to -0.4(-0.54, -0.26) and from -0.52(-0.67, -0.38) to -0.31(-0.44, -0.11) in the testosterone and oxandrolone-treated groups, respectively, [median (25%, 75%)]. An increase in radius Z-score from -0.52(-0.65, -0.25) to -0.4(-0.54, -0.15) and from -0.51(-0.61, -0.21) to -0.37(-0.47, -0.07) in the testosterone- and oxandrolone-treated groups respectively [median (25%,75%)]. Z-score SOS decreased in the observation group -0.5(-0.66, -0.3) to -0.69(-0.85, -0.54) and -0.5(-0.59, -0.41) to -0.81(-0.95, -0.55) in tibia (P = 0.032) and radius (P = 0.029), respectively. Despite the fact that QUS remained in the normative range in all patients, a clear deterioration was demonstrated in untreated CGDP patients. CONCLUSION longitudinal follow-up of patients with CGDP may detect an early pattern of deterioration of bone mass.
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Affiliation(s)
- Zvi Zadik
- The Pediatric Endocrine Unit, Kaplan Medical Center, Hadassah Medical School, 76100 Rehovot, Israel.
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19
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Abstract
Although 80% of the variance in bone mass is determined genetically, there are many other factors which influence the accumulation of bone in early life and affect future risks of osteoporosis. This review considers the genetic, fetal, and environmental influences on bone mass acquisition in healthy children, and highlights important areas where paediatricians may have a role by counselling children and their families to adopt a healthy lifestyle which promotes bone health.
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Affiliation(s)
- J H Davies
- Department of Child Health, Cardiff University, Heath Park, Cardiff CF14 4XN, UK.
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Goodyer CG, Figueiredo RM, Krackovitch S, De Souza Li L, Manalo JA, Zogopoulos G. Characterization of the growth hormone receptor in human dermal fibroblasts and liver during development. Am J Physiol Endocrinol Metab 2001; 281:E1213-20. [PMID: 11701436 DOI: 10.1152/ajpendo.2001.281.6.e1213] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Human tissues express growth hormone receptors (hGHR) by the 3rd mo of gestation. We assessed developmental changes in hGHR function in fibroblasts and liver, testing binding and hormonal response. Fetal cells showed low but reproducible hGH binding. No age-related changes occurred in fibroblasts (9 wk-34 yr). In contrast, there was a fourfold increase in hGH binding in postnatal liver, with a sixfold increase in hGHR mRNA. Both full-length and truncated hGHR mRNAs were detected in all livers. Cross-linking revealed a larger hGH/receptor complex in fetal liver. Fetal hepatocytes produced 10 times more insulin-like growth factor (IGF)-II than IGF-I, and responded to hGH (150 ng/ml) with a significant increase in IGF-II. Fetal hepatocytes secreted three IGF-binding proteins (IGFBPs), including IGFBP1, but not IGFBP3. hGH did not alter fetal hepatocyte IGFBPs but stimulated glucose uptake. Exposure of fibroblasts to hGH decreased hGH binding only in >1-yr postnatal fibroblasts, whereas treatment with dexamethasone (100-400 nM) increased binding only in postnatal cells. Thus, although fetal hepatocytes and fibroblasts possess functional hGHR, these receptors (and/or their signaling pathways) are immature or have adapted to the in utero environment.
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Affiliation(s)
- C G Goodyer
- Department of Pediatrics, McGill University, Montreal, Quebec, Canada H3Z 2Z3.
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Longo N, Singh R, Elsas LJ. Decreased half-life of insulin-like growth factor I in Rabson-Mendenhall syndrome. J Inherit Metab Dis 2001; 24:546-50. [PMID: 11757582 DOI: 10.1023/a:1012411709972] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Rabson-Mendenhall syndrome is an autosomal recessive disorder of insulin signalling caused by mutations in the insulin receptor gene. Affected patients are insensitive to exogenous insulin. Insulin-like growth factor I (IGF-I), whose receptor is similar to the one for insulin and is not impaired in this condition, is not always effective in these patients. To understand the reason for this failure, IGF-I concentrations were measured in a patient after subcutaneous injection of 0.1 and 0.2 mg/kg of rhIGF-I. IGF-I concentrations increased only transiently because of the short half-life (1.3-3 h, compared to a normal range of 17-22 h). No correlation was found between IGF-I concentrations and glucose or insulin concentrations. The short half-life of IGF-I may contribute to treatment failure in patients with inherited insulin-resistant syndromes.
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Affiliation(s)
- N Longo
- Division of Medical Genetics, Department of Pediatrics, Emory University, Atlanta, Georgia 30322, USA.
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Friedlander AL, Butterfield GE, Moynihan S, Grillo J, Pollack M, Holloway L, Friedman L, Yesavage J, Matthias D, Lee S, Marcus R, Hoffman AR. One year of insulin-like growth factor I treatment does not affect bone density, body composition, or psychological measures in postmenopausal women. J Clin Endocrinol Metab 2001; 86:1496-503. [PMID: 11297574 DOI: 10.1210/jcem.86.4.7377] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The activity of the hypothalamic-GH-insulin-like growth factor I (hypothalamic-GH-IGF-I) axis declines with age, and some of the catabolic changes of aging have been attributed to the somatopause. The purpose of this investigation was to determine the impact of 1 yr of IGF-I hormone replacement therapy on body composition, bone density, and psychological parameters in healthy, nonobese, postmenopausal women over 60 yr of age. Subjects (n = 16, 70.6 +/- 2.0 yr, 71.8 +/- 2.8 kg) were randomly assigned to either the self-injection IGF-I (15 microg/kg twice daily) or placebo group and were studied at baseline, at 6 months, and at 1 yr of treatment. There were no significant differences between the IGF-I and placebo groups in any of the measured variables at baseline. Fasting blood IGF-I levels were significantly elevated above baseline values (65.6 +/- 11.9 ng/mL) at 6 months (330.0 +/- 52.8) and 12 months (297.7 +/- 40.8) in the IGF-I treated group but did not change in the placebo subjects. Circulating levels of IGF-binding protein-1 and -3 were unaffected by the IGF-I treatment. Bone mineral density of the forearm, lumbar spine, hip, and whole body [as measured by dual-energy x-ray absorptiometry (DXA)] did not change in either group. Similarly, there was no difference in DXA-measured lean mass, fat mass, or percent body fat throughout the treatment intervention. Muscle strength values (grip, bench press, leg press), blood lipid parameters (cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides), and measures of postmeal glucose disposal were not altered by IGF-I treatment, although postmeal insulin levels were lower in the IGF-I subjects at 12 months. IGF-I did not affect bone turnover markers (osteocalcin and type I collagen N-teleopeptide), but subjects who were taking estrogen had significantly lower turnover markers than subjects who were not on estrogen at baseline, 6 months, and 12 months. Finally, the psychological measures of mood and memory were also not altered by the intervention. Despite the initial intent to recruit additional subjects, the study was discontinued after 16 subjects completed the protocol, because the preliminary analyses above indicated that no changes were occurring in any outcome variables, regardless of treatment regimen. Therefore, we conclude that 1 yr of IGF-I treatment, at a dose sufficient to elevate circulating IGF-I to young normal values, is not an effective means to alter body composition or blood parameters nor improve bone density, strength, mood, or memory in older women.
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Affiliation(s)
- A L Friedlander
- Medical Service, Geriatric Research Education Clinical Center, Palo Alto Veterans Administration Health Care System, California 94304, USA.
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Abstract
Since the original somatomedin hypothesis was conceived, a number of important discoveries have allowed investigators to modify the concept. Originally somatic growth was thought to be controlled by pituitary GH and mediated by circulating insulin-like growth factor-I (IGF-I, somatomedin C) expressed exclusively by the liver. With the discovery that IGF-I is produced by most, if not all, tissues, the role of autocrine/paracrine IGF-I vs. the circulating form has been hotly debated. Recent experiments using transgenic and gene-deletion technologies have attempted to answer these questions. In the liverspecific igf-1 gene-deleted mouse model, postnatal growth and development are normal despite the marked reduction in circulating IGF-I and IGF-binding protein levels; free IGF-I levels are normal. Thus, the normal postnatal growth and development in these animals may be due to normal free IGF-I levels (from as yet unidentified sources), although the role of autocrine/paracrine IGF-I has yet to be determined.
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Affiliation(s)
- D Le Roith
- Clinical Endocrinology Branch, National Institutes of Health, Bethesda, Maryland 20892-1758, USA.
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Abstract
Recent case-controlled studies have found increases in the serum levels of insulin-like growth factor-I (IGF-I) in subjects who had, or who eventually developed, prostate or premenopausal breast cancers. Since growth hormone (GH) increases IGF-I levels, concern has been raised regarding its potential role as a cancer initiation factor. The epidemiological studies, which indicate an association between serum IGF-I levels and cancer risk, have not established causality. In fact, several alternative explanations for the elevated serum IGF-I levels in cancer patients may be proposed based on human and animal models. First, an effect of IGF-I causing symptomatic benign tissue hyperplasia may result in an ascertainment bias leading to an initiation of procedures resulting in the diagnosis of asymptomatic cancers. Second, elevated serum IGF-I in cancer patients may originate within the tumor (as suggested by some animal studies). Thirdly, serum IGF-I may actually be a surrogate marker of tissue IGF-I levels or of nutritional factors, which are not under GH control and may be involved in cancer initiation. The role of GH in cancer initiation is further negated by the fact that in acromegaly, the incidence of cancer, other than possibly colonic neoplasia does not appear to be significantly increased. Furthermore, GH transgenic mice, with high IGF-I levels, do not develop breast, prostate, or colonic malignancies. It is known that IGFBP-3 can inhibit IGF action on cancer cells in vitro and also can induce apoptosis via an IGF-independent mechanism. Importantly, in addition to increasing IGF-I levels, GH also increases the serum levels of IGFBP-3 and serum IGFBP-3 levels have been shown to be negatively correlated with the risk of cancer in the above mentioned epidemiological studies and in a similar study on colon cancer. These studies suggest that cancer risk is increased in individuals in whom both high IGF-I levels and low IGFBP-3 levels are present. In subjects treated with GH, IGF-I and IGFBP-3 levels both rise together and are not within the elevated cancer-risk range, based on published studies. Long-term studies are needed to assess the potential risks, including the long-term cancer risk associated with GH therapy. These should take into account several factors, including the duration of exposure, the risk magnitude associated with the degree of serum IGF-I elevation, and the adjusted risk based on a concomitant increase in IGFBP-3 levels. Since GH treated patients often have sub-normal IGF-I serum levels, which normalize on therapy, one might predict that their cancer risk on GH therapy should not increase above the normal population. Until further research in the area dictates otherwise, on-going cancer surveillance and routine monitoring of serum IGF-I and IGFBP-3 levels in GH-recipients should be the standard of care. At present, the data that are available do not warrant a change in our current management of approved indications for GH therapy.
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Affiliation(s)
- P Cohen
- Department of Pediatrics, Mattel Children's Hospital, UCLA, Los Angeles, CA 90095-1752, USA.
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