Prehepatic secretion and disposal of insulin in obese adolescents as estimated by three-hour, eight-sample oral glucose tolerance tests
The body compensates for early-stage insulin resistance by increasing insulin secretion. A reliable and easy-to-use mathematical assessment of insulin secretion and disposal could be a valuable tool for identifying patients at risk for the development of type 2 diabetes. Because the pathophysiology of insulin resistance is incompletely understood, assessing insulin metabolism with minimal assumptions regarding its metabolic regulation is a major challenge. To assess insulin secretion and indexes of insulin disposal, our marginalized and regularized absorption approach (MRA) was applied to a sparse sampling oral glucose tol...
Source: AJP: Endocrinology and Metabolism - June 30, 2016 Category: Endocrinology Authors: Vogt, J. A., Domzig, C., Wabitsch, M., Denzer, C. Tags: Call for Papers Source Type: research
AP2-NR4A3 transgenic mice display reduced serum epinephrine because of increased catecholamine catabolism in adipose tissue
In conclusion, overexpression of NR4A3 in adipocytes produces a complex phenotype characterized by impaired glucose metabolism and low serum catecholamines due to enhanced degradation by adipose tissue. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - June 30, 2016 Category: Endocrinology Authors: Walton, R. G., Zhu, X., Tian, L., Heywood, E. B., Liu, J., Hill, H. S., Liu, J., Bruemmer, D., Yang, Q., Fu, Y., Garvey, W. T. Tags: Call for Papers Source Type: research
Glucocorticoid antagonism limits adiposity rebound and glucose intolerance in young male rats following the cessation of daily exercise and caloric restriction
In this study, we examined the effect of mifepristone, a glucocorticoid (GC) receptor antagonist, on limiting adipose tissue mass gain and preserving whole body insulin sensitivity following the cessation of daily running and CR. We calorically restricted male Sprague-Dawley rats and provided access to voluntary running wheels for 3 wk followed by locking of the wheels and reintroduction to ad libitum feeding with or without mifepristone (80 mg·kg–1·day–1) for 1 wk. Cessation of daily running and CR increased HOMA-IR and visceral adipose mass as well as glucose and insulin area under the curve dur...
Source: AJP: Endocrinology and Metabolism - June 30, 2016 Category: Endocrinology Authors: Teich, T., Dunford, E. C., Porras, D. P., Pivovarov, J. A., Beaudry, J. L., Hunt, H., Belanoff, J. K., Riddell, M. C. Tags: Call for Papers Source Type: research
Insights into the role of neuronal glucokinase
We describe clinical implications from these advances in our knowledge, especially for developing novel treatments for diabetes and obesity. Further research required to extend our knowledge and help our efforts to tackle the diabetes and obesity epidemics is suggested. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - June 30, 2016 Category: Endocrinology Authors: De Backer, I., Hussain, S. S., Bloom, S. R., Gardiner, J. V. Tags: Call for Papers Source Type: research
Neuroinflammatory and autonomic mechanisms in diabetes and hypertension
Interdisciplinary studies in the research fields of endocrinology and immunology show that obesity-associated overnutrition leads to neuroinflammatory molecular changes, in particular in the hypothalamus, chronically causing various disorders known as elements of metabolic syndrome. In this process, neural or hypothalamic inflammation impairs the neuroendocrine and autonomic regulation of the brain over blood pressure and glucose homeostasis as well as insulin secretion, and elevated sympathetic activation has been appreciated as a critical mediator. This review describes the involved physiology and mechanisms, with a focu...
Source: AJP: Endocrinology and Metabolism - June 30, 2016 Category: Endocrinology Authors: Han, C., Rice, M. W., Cai, D. Tags: Call for Papers Source Type: research
Na,K-ATPase regulation in skeletal muscle
Skeletal muscle contains one of the largest and the most dynamic pools of Na,K-ATPase (NKA) in the body. Under resting conditions, NKA in skeletal muscle operates at only a fraction of maximal pumping capacity, but it can be markedly activated when demands for ion transport increase, such as during exercise or following food intake. Given the size, capacity, and dynamic range of the NKA pool in skeletal muscle, its tight regulation is essential to maintain whole body homeostasis as well as muscle function. To reconcile functional needs of systemic homeostasis with those of skeletal muscle, NKA is regulated in a coordinated...
Source: AJP: Endocrinology and Metabolism - June 30, 2016 Category: Endocrinology Authors: Pirkmajer, S., Chibalin, A. V. Tags: Review Source Type: research
Enteral {beta}-hydroxy-{beta}-methylbutyrate supplementation increases protein synthesis in skeletal muscle of neonatal pigs
Many low-birth weight infants are at risk for poor growth due to an inability to achieve adequate protein intake. Administration of the amino acid leucine stimulates protein synthesis in skeletal muscle of neonates. To determine the effects of enteral supplementation of the leucine metabolite β-hydroxy-β-methylbutyrate (HMB) on protein synthesis and the regulation of translation initiation and degradation pathways, overnight-fasted neonatal pigs were studied immediately (F) or fed one of five diets for 24 h: low-protein (LP), high-protein (HP), or LP diet supplemented with 4 (HMB4), 40 (HMB40), or 80 (HMB80) μ...
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Kao, M., Columbus, D. A., Suryawan, A., Steinhoff-Wagner, J., Hernandez-Garcia, A., Nguyen, H. V., Fiorotto, M. L., Davis, T. A. Tags: Articles Source Type: research
Vitamin D status and metabolism in an ovine pregnancy model: effect of long-term, high-altitude hypoxia
Vitamin D status increases during healthy mammalian pregnancy, but the molecular determinants remain uncharacterized. The first objective of this study was to determine the effects of pregnancy, and the second objective was to examine the role of chronic hypoxia on vitamin D status and metabolism in an ovine model. We analyzed the plasma levels of cholecalciferol, 25-OH-D, and 1α,25-(OH)2D in nonpregnant ewes, near-term pregnant ewes, and their fetuses exposed to normoxia (low altitude) or hypoxia (high-altitude) for 100 days. Hypoxic sheep had increased circulating levels of 25-OH-D and 1α,25-(OH)2D compared w...
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Goyal, R., Billings, T. L., Mansour, T., Martin, C., Baylink, D. J., Longo, L. D., Pearce, W. J., Mata-Greenwood, E. Tags: Articles Source Type: research
Gut hormone secretion, gastric emptying, and glycemic responses to erythritol and xylitol in lean and obese subjects
In conclusion, acute ingestion of erythritol and xylitol stimulates gut hormone release and slows down gastric emptying, whereas there is no or only little effect on insulin release. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Wölnerhanssen, B. K., Cajacob, L., Keller, N., Doody, A., Rehfeld, J. F., Drewe, J., Peterli, R., Beglinger, C., Meyer-Gerspach, A. C. Tags: Articles Source Type: research
Loss of CTRP5 improves insulin action and hepatic steatosis
The gene that encodes C1q/TNF-related protein 5 (CTRP5), a secreted protein of the C1q family, is mutated in individuals with late-onset retinal degeneration. CTRP5 is widely expressed outside the eye and also circulates in plasma. Its physiological role in peripheral tissues, however, has yet to be elucidated. Here, we show that Ctrp5 expression is modulated by fasting and refeeding, and by different diets, in mice. Adipose expression of CTRP5 was markedly upregulated in obese and diabetic humans and in genetic and dietary models of obesity in rodents. Furthermore, human CTRP5 expression in the subcutaneous fat depot posi...
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Lei, X., Rodriguez, S., Petersen, P. S., Seldin, M. M., Bowman, C. E., Wolfgang, M. J., Wong, G. W. Tags: Articles Source Type: research
Increased ADAMTS1 mediates SPARC-dependent collagen deposition in the aging myocardium
In conclusion, ADAMTS1 is an important mediator of SPARC-regulated cardiac aging. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Toba, H., de Castro Bras, L. E., Baicu, C. F., Zile, M. R., Lindsey, M. L., Bradshaw, A. D. Tags: Call for Papers Source Type: research
Involvement of a proapoptotic gene (BBC3) in islet injury mediated by cold preservation and rewarming
In this study, we examined mechanisms of pancreatic cold preservation and rewarming-induced injury by interrogating the proapoptotic gene BBC3/Bbc3, also known as Puma (p53 upregulated modulator of apoptosis), using three experimental models: 1) bioluminescence imaging of isolated luciferase-transgenic ("Firefly") Lewis rat islets, 2) cold preservation of en bloc-harvested pancreata from Bbc3-knockout (KO) mice, and 3) cold preservation and rewarming of human pancreata and isolated islets. Cold preservation-mediated islet injury occurred during rewarming in "Firefly" islets. Silencing Bbc3 by transfecting Bbc3 siRNA into i...
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Omori, K., Kobayashi, E., Komatsu, H., Rawson, J., Agrawal, G., Parimi, M., Oancea, A. R., Valiente, L., Ferreri, K., Al-Abdullah, I. H., Kandeel, F., Takahashi, M., Mullen, Y. Tags: Call for Papers Source Type: research
Exposure to environmentally persistent free radicals during gestation lowers energy expenditure and impairs skeletal muscle mitochondrial function in adult mice
We have investigated the effects of in utero exposure to environmentally persistent free radicals (EPFRs) on growth, metabolism, energy utilization, and skeletal muscle mitochondria in a mouse model of diet-induced obesity. Pregnant mice were treated with laboratory-generated, combustion-derived particular matter (MCP230). The adult offspring were placed on a high-fat diet for 12 wk, after which we observed a 9.8% increase in their body weight. The increase in body size observed in the MCP230-exposed mice was not associated with increases in food intake but was associated with a reduction in physical activity and lower ene...
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Stephenson, E. J., Ragauskas, A., Jaligama, S., Redd, J. R., Parvathareddy, J., Peloquin, M. J., Saravia, J., Han, J. C., Cormier, S. A., Bridges, D. Tags: Call for Papers Source Type: research
Hypothalamic roles of mTOR complex I: integration of nutrient and hormone signals to regulate energy homeostasis
Mammalian or mechanistic target of rapamycin (mTOR) senses nutrient, energy, and hormone signals to regulate metabolism and energy homeostasis. mTOR activity in the hypothalamus, which is associated with changes in energy status, plays a critical role in the regulation of food intake and body weight. mTOR integrates signals from a variety of "energy balancing" hormones such as leptin, insulin, and ghrelin, although its action varies in response to these distinct hormonal stimuli as well as across different neuronal populations. In this review, we summarize and highlight recent findings regarding the functional roles of mTO...
Source: AJP: Endocrinology and Metabolism - June 13, 2016 Category: Endocrinology Authors: Hu, F., Xu, Y., Liu, F. Tags: Call for Papers Source Type: research
High-intensity exercise training increases the diversity and metabolic capacity of the mouse distal gut microbiota during diet-induced obesity
Diet and exercise underpin the risk of obesity-related metabolic disease. Diet alters the gut microbiota, which contributes to aspects of metabolic disease during obesity. Repeated exercise provides metabolic benefits during obesity. We assessed whether exercise could oppose changes in the taxonomic and predicted metagenomic characteristics of the gut microbiota during diet-induced obesity. We hypothesized that high-intensity interval training (HIIT) would counteract high-fat diet (HFD)-induced changes in the microbiota without altering obesity in mice. Compared with chow-fed mice, an obesity-causing HFD decreased the Bact...
Source: AJP: Endocrinology and Metabolism - May 31, 2016 Category: Endocrinology Authors: Denou, E., Marcinko, K., Surette, M. G., Steinberg, G. R., Schertzer, J. D. Tags: Articles Source Type: research
