Short-term high-fat feeding induces islet macrophage infiltration and {beta}-cell replication independently of insulin resistance in mice
This study suggests the existence of M-mediated mechanisms in β-cell replication that are independent of insulin resistance. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - October 4, 2016 Category: Endocrinology Authors: Woodland, D. C., Liu, W., Leong, J., Sears, M. L., Luo, P., Chen, X. Tags: Call for Papers Source Type: research
Molecular patterns of diffuse and nodular parathyroid hyperplasia in long-term hemodialysis
In conclusion, our study suggests the RANGRF transcript, which controls RNA metabolism, to be likely involved in pathways associated with the switch to nodular parathyroid growth. This transcript, along with PIN1 transcript, which influences parathyroid hormone secretion, may represent new therapeutical targets to cure secondary hyperparathyroidism. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - September 30, 2016 Category: Endocrinology Authors: Tycova, I., Sulkova, S. D., Stepankova, J., Krejcik, Z., Merkerova, M. D., Stranecky, V., Hruba, P., Girmanova, E., Cernoch, M., Lipar, K., Marada, T., Povysil, C., Viklicky, O. Tags: Articles Source Type: research
Benzimidazole derivative small-molecule 991 enhances AMPK activity and glucose uptake induced by AICAR or contraction in skeletal muscle
AMP-activated protein kinase (AMPK) plays diverse roles and coordinates complex metabolic pathways for maintenance of energy homeostasis. This could be explained by the fact that AMPK exists as multiple heterotrimer complexes comprising a catalytic α-subunit (α1 and α2) and regulatory β (β1 and β2)- and (1, 2, 3)-subunits, which are uniquely distributed across different cell types. There has been keen interest in developing specific and isoform-selective AMPK-activating drugs for therapeutic use and also as research tools. Moreover, establishing ways of enhancing cellular AMPK activity woul...
Source: AJP: Endocrinology and Metabolism - September 30, 2016 Category: Endocrinology Authors: Bultot, L., Jensen, T. E., Lai, Y.-C., Madsen, A. L. B., Collodet, C., Kviklyte, S., Deak, M., Yavari, A., Foretz, M., Ghaffari, S., Bellahcene, M., Ashrafian, H., Rider, M. H., Richter, E. A., Sakamoto, K. Tags: Articles Source Type: research
Direct effect of glucocorticoids on glucose-activated adult rat {beta}-cells increases their cell number and their functional mass for transplantation
Compounds that increase β-cell number can serve as β-cell replacement therapies in diabetes. In vitro studies have identified several agents that can activate DNA synthesis in primary β-cells but only in small percentages of cells and without demonstration of increases in cell number. We used whole well multiparameter imaging to first screen a library of 1,280 compounds for their ability to recruit adult rat β-cells into DNA synthesis and then assessed influences of stimulatory agents on the number of living cells. The four compounds with highest β-cell recruitment were glucocorticoid (GC) receptor...
Source: AJP: Endocrinology and Metabolism - September 30, 2016 Category: Endocrinology Authors: Assefa, Z., Akbib, S., Lavens, A., Stange, G., Ling, Z., Hellemans, K. H., Pipeleers, D. Tags: Articles Source Type: research
Loss of CTRP1 disrupts glucose and lipid homeostasis
C1q/TNF-related protein 1 (CTRP1) is a conserved plasma protein of the C1q family with notable metabolic and cardiovascular functions. We have previously shown that CTRP1 infusion lowers blood glucose and that transgenic mice with elevated circulating CTRP1 are protected from diet-induced obesity and insulin resistance. Here, we used a genetic loss-of-function mouse model to address the requirement of CTRP1 for metabolic homeostasis. Despite similar body weight, food intake, and energy expenditure, Ctrp1 knockout (KO) mice fed a low-fat diet developed insulin resistance and hepatic steatosis. Impaired glucose metabolism in...
Source: AJP: Endocrinology and Metabolism - September 30, 2016 Category: Endocrinology Authors: Rodriguez, S., Lei, X., Petersen, P. S., Tan, S. Y., Little, H. C., Wong, G. W. Tags: Articles Source Type: research
Insulin does not stimulate muscle protein synthesis during increased plasma branched-chain amino acids alone but still decreases whole body proteolysis in humans
In conclusion, insulin does not stimulate muscle protein synthesis in the presence of increased circulating levels of plasma BCAA alone. Insulin's suppressive effect on proteolysis is observed independently of the levels of circulating plasma BCAA. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - September 30, 2016 Category: Endocrinology Authors: Everman, S., Meyer, C., Tran, L., Hoffman, N., Carroll, C. C., Dedmon, W. L., Katsanos, C. S. Tags: Articles Source Type: research
Central GIP signaling stimulates peripheral GIP release and promotes insulin and pancreatic polypeptide secretion in nonhuman primates
Glucose-dependent insulinotropic polypeptide (GIP) has important actions on whole body metabolic function. GIP and its receptor are also present in the central nervous system and have been linked to neurotrophic actions. Metabolic effects of central nervous system GIP signaling have not been reported. We investigated whether centrally administered GIP could increase peripheral plasma GIP concentrations and influence the metabolic response to a mixed macronutrient meal in nonhuman primates. An infusion and sampling system was developed to enable continuous intracerebroventricular (ICV) infusions with serial venous sampling ...
Source: AJP: Endocrinology and Metabolism - September 30, 2016 Category: Endocrinology Authors: Higgins, P. B., Shade, R. E., Rodriguez-Sanchez, I. P., Garcia-Forey, M., Tejero, M. E., Voruganti, V. S., Cole, S. A., Comuzzie, A. G., Folli, F. Tags: Call for Papers Source Type: research
Muscle expression of a malonyl-CoA-insensitive carnitine palmitoyltransferase-1 protects mice against high-fat/high-sucrose diet-induced insulin resistance
Impaired skeletal muscle mitochondrial fatty acid oxidation (mFAO) has been implicated in the etiology of insulin resistance. Carnitine palmitoyltransferase-1 (CPT1) is a key regulatory enzyme of mFAO whose activity is inhibited by malonyl-CoA, a lipogenic intermediate. Whereas increasing CPT1 activity in vitro has been shown to exert a protective effect against lipid-induced insulin resistance in skeletal muscle cells, only a few studies have addressed this issue in vivo. We thus examined whether a direct modulation of muscle CPT1/malonyl-CoA partnership is detrimental or beneficial for insulin sensitivity in the context ...
Source: AJP: Endocrinology and Metabolism - September 13, 2016 Category: Endocrinology Authors: Vavrova, E., Lenoir, V., Alves-Guerra, M.-C., Denis, R. G., Castel, J., Esnous, C., Dyck, J. R. B., Luquet, S., Metzger, D., Bouillaud, F., Prip-Buus, C. Tags: Articles Source Type: research
Liraglutide prevents microvascular insulin resistance and preserves muscle capillary density in high-fat diet-fed rats
In this study, we aim to determine the effects of sustained stimulation of the GLP-1 receptors on insulin-mediated capillary recruitment and metabolic insulin responses, small arterial endothelial function, and muscle capillary density. Rats were fed a high-fat diet (HFD) for 4 wk with or without simultaneous administration of liraglutide and subjected to a euglycemic hyperinsulinemic clamp for 120 min after an overnight fast. Insulin-mediated muscle microvascular recruitment and muscle oxygenation were determined before and during insulin infusion. Muscle capillary density was determined and distal saphenous artery used f...
Source: AJP: Endocrinology and Metabolism - September 13, 2016 Category: Endocrinology Authors: Chai, W., Fu, Z., Aylor, K. W., Barrett, E. J., Liu, Z. Tags: Articles Source Type: research
Reply to letter to the editor: at thermoneutrality, neither the lean nor the obese freeze
(Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - September 11, 2016 Category: Endocrinology Authors: Fischer, A. W., Csikasz, R. I., von Essen, G., Cannon, B., Nedergaard, J. Tags: Letter to the Editor Source Type: research
Some problems with translating the insulating effect of obesity from mice to men
(Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - September 11, 2016 Category: Endocrinology Authors: Jay, O., Raubenheimer, D. Tags: Letter to the Editor Source Type: research
Release of skeletal muscle peptide fragments identifies individual proteins degraded during insulin deprivation in type 1 diabetic humans and mice
In conclusion, identifying LMW peptide fragments offers an approach to determine the degradation of individual proteins. Insulin deprivation increases degradation of select proteins and provides insight into the regulatory role of insulin in maintaining proteome homeostasis, especially of mitochondria. (Source: AJP: Endocrinology and Metabolism)
Source: AJP: Endocrinology and Metabolism - September 11, 2016 Category: Endocrinology Authors: Robinson, M. M., Dasari, S., Karakelides, H., Bergen, H. R., Nair, K. S. Tags: Articles Source Type: research
Hepatic functions of GLP-1 and its based drugs: current disputes and perspectives
GLP-1 and its based drugs possess extrapancreatic metabolic functions, including that in the liver. These direct hepatic metabolic functions explain their therapeutic efficiency for subjects with insulin resistance. The direct hepatic functions could be mediated by previously assumed "degradation" products of GLP-1 without involving canonic GLP-1R. Although GLP-1 analogs were created as therapeutic incretins, extrapancreatic functions of these drugs, as well as native GLP-1, have been broadly recognized. Among them, the hepatic functions are particularly important. Postprandial GLP-1 release contributes to insulin secretio...
Source: AJP: Endocrinology and Metabolism - September 11, 2016 Category: Endocrinology Authors: Jin, T., Weng, J. Tags: Perspectives Source Type: research
Physiological processes underlying organ injury in alcohol abuse
This review summarizes the American Physiological Society (APS) Presidential Symposium 1 entitled "Physiological Processes Underlying Organ Injury in Alcohol Abuse" at the 2016 Experimental Biology meeting. The symposium was organized by Dr. Patricia Molina, past president of the APS, was held on April 3 at the Convention Center in San Diego, CA, and was funded by the National Institute on Alcohol Abuse and Alcoholism. The "Physiological Processes Underlying Organ Injury in Alcohol Abuse Symposium" assembled experts and leaders in the field and served as a platform to discuss and share knowledge on the latest developments ...
Source: AJP: Endocrinology and Metabolism - September 11, 2016 Category: Endocrinology Authors: Souza-Smith, F. M., Lang, C. H., Nagy, L. E., Bailey, S. M., Parsons, L. H., Murray, G. J. Tags: Review Source Type: research
Control of skeletal muscle atrophy in response to disuse: clinical/preclinical contentions and fallacies of evidence
Muscle wasting resulting wholly or in part from disuse represents a serious medical complication that, when prolonged, can increase morbidity and mortality. Although much knowledge has been gained over the past half century, the underlying etiology by which disuse alters muscle proteostasis remains enigmatic. Multidisciplinary and novel methodologies are needed to fill gaps and overcome barriers to improved patient care. The present review highlights seminal concepts from a symposium at Experimental Biology 2016. These proceedings focus on 1) the role of insulin resistance in mediating disuse-induced changes in muscle prot...
Source: AJP: Endocrinology and Metabolism - September 11, 2016 Category: Endocrinology Authors: Atherton, P. J., Greenhaff, P. L., Phillips, S. M., Bodine, S. C., Adams, C. M., Lang, C. H. Tags: Review Source Type: research
