International Journal of Endocrinology Endocrine Function in Aging Guest Editors: Huan Cai, Alan S. Mcneilly, Louis M. Luttrell, and Bronwen Martin Endocrine Function in Aging International Journal of Endocrinology Endocrine Function in Aging Guest Editors: Huan Cai, Alan S. Mcneilly, Louis M. Luttrell, and Bronwen Martin Copyright © 2012 Hindawi Publishing Corporation. All rights reserved. This is a special issue published in “International Journal of Endocrinology.” All articles are open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Editorial Board Anil K. Agarwal, USA Daniela Jezova, Slovakia Stacia A. Sower, USA Stephen L. Atkin, UK Abbas E. Kitabchi, USA Ajai Kumar Srivastav, India Leon Bach, Australia Fernand Labrie, Canada Stanko S. Stojilkovic, USA Ariel L. Barkan, USA Mario Maggi, Italy Robert S. Tan, USA Chawnshang Chang, USA MariaI.New,USA Vin Tangpricha, USA Shern L. Chew, UK Furio M. Pacini, Italy Stuart Tobet, USA Paresh K. Dandona, USA Faustino R. Perez-L´ opez,´ Spain Jack R. Wall, Australia MariaL.Dufau,USA Barry Posner, Canada Paul M. Yen, USA Dariush Elahi, USA Mark A. Sheridan, UK Andreas Hoflich,¨ Germany Shunichi Shimasaki, USA Contents Endocrine Function in Aging,HuanCai,AlanS.Mcneilly,LouisM.Luttrell,andBronwenMartin Volume 2012, Article ID 872478, 3 pages Free Triiodothyronine and Cholesterol Levels in Euthyroid Elderly T2DM Patients,F.Strollo,I.Carucci, M. More,` G. Marico, G. Strollo, M. A. Masini, and S. Gentile Volume 2012, Article ID 420370, 7 pages Aging and Bone Health in Individuals with Developmental Disabilities, Joan Jasien, Caitlin M. Daimon, Stuart Maudsley, Bruce K. Shapiro, and Bronwen Martin Volume 2012, Article ID 469235, 10 pages Central Role of the EGF Receptor in Neurometabolic Aging, Sana Siddiqui, Meng Fang, Bin Ni, Daoyuan Lu, Bronwen Martin, and Stuart Maudsley Volume 2012, Article ID 739428, 14 pages Primary Hyperparathyroidism in Older People: Surgical Treatment with Minimally Invasive Approaches and Outcome, Chiara Dobrinja, Marta Silvestri, and Nicolo` de Manzini Volume 2012, Article ID 539542, 6 pages Partial Androgen Deficiency, Depression, and Testosterone Supplementation in Aging Men, Mario Amore, Marco Innamorati, Sara Costi, Leo Sher, Paolo Girardi, and Maurizio Pompili Volume 2012, Article ID 280724, 17 pages Muscular Dystrophies at Different Ages: Metabolic and Endocrine Alterations, Oriana del Roc´ıo Cruz Guzman,´ Ana Laura Chavez´ Garc´ıa, and Maricela Rodr´ıguez-Cruz Volume 2012, Article ID 485376, 12 pages Metabolic Context Regulates Distinct Hypothalamic Transcriptional Responses to Antiaging Interventions, Alexis M. Stranahan, Bronwen Martin, Wayne Chadwick, Sung-Soo Park, Liyun Wang, Kevin G. Becker, William H. WoodIII, Yongqing Zhang, and Stuart Maudsley Volume 2012, Article ID 732975, 15 pages Sarcopenia and Age-Related Endocrine Function, Kunihiro Sakuma and Akihiko Yamaguchi Volume 2012, Article ID 127362, 10 pages Pancreatic Function, Type 2 Diabetes, and Metabolism in Aging, Zhenwei Gong and Radhika H. Muzumdar Volume 2012, Article ID 320482, 13 pages Interpretation of Hormone Levels in Older Patients: Points for Consideration, Krystyna Sztefko and Patrycja Szybowska Volume 2012, Article ID 712425, 7 pages Interactions between Serum Adipokines and Osteocalcin in Older Patients with Hip Fracture, Alexander Fisher, Wichat Srikusalanukul, Michael Davis, and Paul Smith Volume 2012, Article ID 684323, 11 pages Hindawi Publishing Corporation International Journal of Endocrinology Volume 2012, Article ID 872478, 3 pages doi:10.1155/2012/872478 Editorial Endocrine Function in Aging Huan Cai,1 Alan S. Mcneilly,2 Louis M. Luttrell,3 and Bronwen Martin1 1 Metabolism Unit, National Institute on Aging, National Institutes of Health, 251 Bayview Boulevard, Baltimore, MD 21224, USA 2 MRC Centre for Reproductive Health, The Queen’s Medical Research Institute, University of Edinburgh, 47 Little France Crescent, Edinburgh EH16 4TJ, UK 3 Division of Endocrinology, Diabetes & Medical Genetics, Department of Medicine, Medical University of South Carolina, Charleston, SC 29425, USA Correspondence should be addressed to Bronwen Martin, [email protected] Received 9 December 2012; Accepted 9 December 2012 Copyright © 2012 Huan Cai et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The endocrine system in higher mammals represents one of result in an improvement of quality of life and also overall the most complex and fundamental systems that regulates lifespan. Thus, endocrine functions in the aging context are nearly all of an organism’s biological functions. This system is important fields of intense clinical and scientific interest and composed of multiple organs, tissues, hormones, and recep- form the focus of this special issue. tor modalities. Its ability to regulate critical functions such Thepapersinthisspecialissuearefocuseduponoriginal as reproduction, development, metabolism, stress responses, research papers and review papers concerning several impor- blood pressure, wakefulness, and digestion places it as one tant molecular and tissue systems vital to the maintenance of the most important regulators of life-long physiology. of the endocrine system in aging, that is, pancreatic function Therefore, at any one point in time the physiological status and type 2 diabetes mellitus (T2DM); testosterone deficiency of the majority of organs in the body is a function of the and depression; metabolic and endocrine alterations in activity of the whole endocrine system. However, while muscle dystrophies and sarcopenia; serum adipokines and appreciating the role of the endocrine system in such “fro- osteocalcin in older patients with hip fracture; geronto- zen” points in time is important, the temporal variation logical neuroendocrine axis organization and disruption; in endocrine function across one’s lifespan is of crucial correlation of thyroid hormones and lipid profiles in elderly interest to researchers investigating age-related disorders. T2DM patients; minimally invasive approaches to parathy- Theimportanceofgerontologicalresearchisbecomingmore roid surgery in elderly patients; the proper interpretation of and more evident, given the ever-increasing proportion of hormones and tumor marker measurements in the geriatric aged people in Western countries. population. Aging is a natural process that involves a general decline As we have stated, aging is an important risk factor for in many physiological functions with time. Aging is generi- metabolic disorders, including obesity, impaired glucose tol- cally associated with a reduced capacity to maintain home- erance, and type 2 diabetes. Aging has long been associated ostasis and effective repair mechanisms, resulting in loss in multiple animal species with the insulin/insulin-like of function, senescence, and eventually death. It is obvious growth factor-1 (IGF-1) signaling system. Z. Gong and R. H. that the functions of endocrine organs alter during the Muzumdar summarize in their paper the current evidence aging process, resulting in a higher prevalence of endocrine on how aging affects pancreatic β-cell function, β-cell mass, malfunction-related disorders in the elderly population. insulin secretion, and insulin sensitivity. They also review the Enhanced knowledge and appreciation of endocrine func- effects of aging on the relationship between insulin sensitivity tions in aging will likely lead to the development of successful and insulin secretion. Accelerated insulin resistance appears pharmacological or lifestyle therapies to treat endocrine- to be one of the strongest hallmarks of advanced physiolog- related diseases in elderly patients. The discovery and devel- ical aging; therefore, a comprehensive understanding of all opment of novel endocrine-targeted remedies will hopefully the defects that impair glucose homeostasis in the elderly 2 International Journal of Endocrinology will likely lead to the development of novel treatments that defects related to sarcopenia. Myostatin inhibition seems may substantially improve life quality and lifespan. to be an intriguing strategy for attenuating sarcopenia as Testosterone deficiency, or hypotestosteronemia, is a well as muscular dystrophy. The authors discussed how widely recognized hormonal alteration strongly associated therapeutic supplementation with growth hormone, IGF-I, with male aging. The review paper by M. Amore et al. or estrogen had a minor sarcopenia-inhibiting effect, and comprehensively summarizes the current understanding of that testosterone supplementation in large doses had several the correlation between depressive symptoms with a syn- side effects, even though it significantly improved muscle drome called partial androgen deficiency of the aging male defects. Ghrelin mimetics could also potentially be beneficial (PADAM). This paper highlights the potential benefits of and reverse the dysfunctional catabolic state associated with testosterone treatment upon mood and affective disorders. sarcopenia in the elderly population. While supplementation with testosterone fails to show sound Low bone mass density, a classical age-related health issue evidence of effectiveness in the treatment of depression, and a known health concern for fair-skinned,