76 research outputs found
Reduced incorporation of Fatty acids into triacylglycerol in myotubes from obese individuals with type 2 diabetes.
Altered skeletal muscle lipid metabolism is a hallmark feature of type 2 (T2D). Here we investigated muscle lipid turnover in T2D versus BMI- controls and examined if putative in vivo differences would be preserved myotubes.Male obese T2D individuals (T2D) (n=6) and their BMI-matched (C) (n=6) underwent a hyperinsulinemic-euglycemic clamp, VO2max test, underwater weighing and muscle biopsy of v. lateralis. 14C-palmitate and 14C-oleate oxidation rates and incorporation into lipids were measured tissue, as well as in primary myotubes.Palmitate oxidation (C: 0.99 +/- T2D: 0.53 +/- 0.07nmol/mg protein; P=0.03) and incorporation of fatty into triacylglycerol (TAG) (C: 0.45 +/- 0.13, T2D: 0.11 +/- 0.02nmol/mg P=0.047) were significantly reduced in muscle homogenates of T2D. These reductions were not retained for palmitate oxidation in primary myotubes (P=0.38); however, incorporation of FAs into TAG was lower in T2D oleate and P=0.11 for palmitate), with a strong correlation of TAG between muscle tissue and primary myotubes (r=0.848, P=0.008).Our data that the ability to incorporate FAs into TAG is an intrinsic feature of muscle cells that is reduced in individuals with T2D
Evidence for a Direct Effect of the NAD+ Precursor Acipimox on Muscle Mitochondrial Function in Humans
The Intentional Use of Service Recovery Strategies to Influence Consumer Emotion, Cognition and Behaviour
Service recovery strategies have been identified as a critical factor in the success of. service organizations. This study develops a conceptual frame work to investigate how specific service recovery strategies influence the emotional, cognitive and negative behavioural responses of . consumers., as well as how emotion and cognition influence negative behavior. Understanding the impact of specific service recovery strategies will allow service providers' to more deliberately and intentionally engage in strategies that result in positive organizational outcomes. This study was conducted using a 2 x 2 between-subjects quasi-experimental design. The results suggest that service recovery has a significant impact on emotion, cognition and negative behavior. Similarly, satisfaction, negative emotion and positive emotion all influence negative behavior but distributive justice has no effect
Correlação entre caracterĂsticas de latossolos e parĂąmetros de equaçÔes de adsorção de cobre e zinco
Biorremediação de um solo contaminado com antraceno sob diferentes condiçÔes fĂsicas e quĂmicas
Composição lignocelulĂłsica e isĂłtopica da vegetação e da matĂ©ria orgĂąnica do solo de uma turfeira tropical: II - substĂąncias hĂșmicas e processos de humificação
Overexpression of PLIN5 in skeletal muscle promotes oxidative gene expression and intramyocellular lipid content without compromising insulin sensitivity
Aims/hypothesis: While lipid deposition in the skeletal muscle is considered to be involved in obesity-associated insulin resistance, neutral intramyocellular lipid (IMCL) accumulation per se does not necessarily induce insulin resistance. We previously demonstrated that overexpression of the lipid droplet coat protein perilipin 2 augments intramyocellular lipid content while improving insulin sensitivity. Another member of the perilipin family, perilipin 5 (PLIN5), is predominantly expressed in oxidative tissues like the skeletal muscle. Here we investigated the effects of PLIN5 overexpression - in comparison with the effects of PLIN2 - on skeletal muscle lipid levels, gene expression profiles and insulin sensitivity. Methods: Gene electroporation was used to overexpress PLIN5 in tibialis anterior muscle of rats fed a high fat diet Eight days after electroporation, insulin-mediated glucose uptake in the skeletal muscle was measured by means of a hyperinsulinemic euglycemic clamp. Electron microscopy, fluorescence microscopy and lipid extractions were performed to investigate IMCL accumulation. Gene expression profiles were obtained using microarrays. Results: TAG storage and lipid droplet size increased upon PLIN5 overexpression. Despite the higher IMCL content, insulin sensitivity was not impaired and DAG and acylcarnitine levels were unaffected. In contrast to the effects of PLIN2 overexpression, microarray data analysis revealed a gene expression profile favoring FA oxidation and improved mitochondrial function. Conclusions/interpretation: Both PLIN2 and PLIN5 increase neutral IMCL content without impeding insulin-mediated glucose uptake. As opposed to the effects of PLIN2 overexpression, overexpression of PUNS in the skeletal muscle promoted expression of a cluster of genes under control of PPAR alpha and PGC1 alpha involved in FA catabolism and mitochondrial oxidation. (C) 2013 Elsevier B.V. All rights reserved
Increased Oxygen Consumption in Human Adipose Tissue From the "Brown Adipose Tissue" Region
Context: Since the discovery of functional brown adipose tissue (BAT) in adult humans, there has been a renewed interest in the physiology of human BAT. Imaging studies from our laboratory and others have shown increased glucose uptake in adipose tissue regions assumed to be BAT in humans. We have also shown that human BAT from the supraclavicular (SCV) region is positive for uncoupling protein-1. To date, however, the oxidative capacity of this adipose tissue (AT) depot has not been characterized in humans. Objective: We hypothesize that oxidative capacity is increased in the AT of the SCV region known to contain human BAT. Design: This was an observational prospective cohort study. Setting: The study was conducted at a referral center. Patients: Participants were 13 patients for whom thyroid gland surgery was indicated. Main Outcome Measure: Basal cellular oxygen consumption in human AT biopsy samples from the SCV region, known to be [F-18]fluorodeoxyglucose positron emission tomography-computed tomography-positive, was compared with the cellular oxygen consumption in subcutaneous white adipose tissue (WAT) from the same region of the same subject. Results: We show for the first time that AT from the human BAT region displays increased oxygen consumption (P <.05), on average 300% higher, than subcutaneous WAT of the same individual. The contribution of the proton leak to maximal respiration increased with age in the WAT but not in the AT from the BAT region. Conclusions: These results suggest that human adipose tissue from the BAT region can be distinguished from subcutaneous WAT by a higher basal oxidative capacity. Additional studies are warranted to further elucidate the metabolic and bioenergetic characteristics of this AT depot in humans
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