C G Walker1, M J Holness, G F Gibbons, M C Sugden. 1. Centre for Diabetes and Metabolic Medicine, Institute of Cellular and Molecular Medicine, Queen Mary, University of London, London, UK.
Abstract
OBJECTIVE: To investigate the impact of peroxisome proliferator-activated receptor alpha deficiency on gene expression of adipose triglyceride lipase and the glycerol transporter aquaglyceroporin 7 in white adipose tissue in the fed and fasted states in relation to glycerol release by isolated adipocytes. MEASUREMENTS: Studies using wild-type and peroxisome proliferator-activated receptor alpha null mice. Hormone and metabolite concentrations, real-time polymerase chain reaction (PCR), basal and stimulated adipocyte lipolysis, estimated by glycerol release. RESULTS: Peroxisome proliferator-activated receptor alpha deficiency blocked the increase in aquaglyceroporin 7 transcript level and attenuated the increase in adipose triglyceride lipase transcript level in white adipose tissue elicited by fasting. Fasting glycerol levels were lower in peroxisome proliferator-activated receptor alpha null than wild-type mice, despite increased mobilization of adipocyte fat reserves in vivo as indicated by reduced adipose tissue masses (three distinct depots) and a significantly lower epididymal adipocyte diameter. Basal net glycerol release was unchanged but beta-adrenergic-stimulated net glycerol release was higher with isolated adipocytes from fasted peroxisome proliferator-activated receptor alpha null mice compared with those of fasted wild-type mice. CONCLUSION: Peroxisome proliferator-activated receptor alpha deficiency prevents effects of fasting to increase adipocyte aquaglyceroporin 7 gene expression, and influences the regulation of inter-tissue glycerol flux after fasting via lowered adipocyte aquaglyceroporin 7 expression. Lowered gene expression of adipose triglyceride lipase and aquaglyceroporin 7 in peroxisome proliferator-activated receptor alpha null mice is not limiting for adipose triglyceride breakdown in vivo during fasting.
OBJECTIVE: To investigate the impact of peroxisome proliferator-activated receptor alpha deficiency on gene expression of adipose triglyceride lipase and the glycerol transporter aquaglyceroporin 7 in white adipose tissue in the fed and fasted states in relation to glycerol release by isolated adipocytes. MEASUREMENTS: Studies using wild-type and peroxisome proliferator-activated receptor alpha null mice. Hormone and metabolite concentrations, real-time polymerase chain reaction (PCR), basal and stimulated adipocyte lipolysis, estimated by glycerol release. RESULTS:Peroxisome proliferator-activated receptor alpha deficiency blocked the increase in aquaglyceroporin 7 transcript level and attenuated the increase in adipose triglyceride lipase transcript level in white adipose tissue elicited by fasting. Fasting glycerol levels were lower in peroxisome proliferator-activated receptor alpha null than wild-type mice, despite increased mobilization of adipocyte fat reserves in vivo as indicated by reduced adipose tissue masses (three distinct depots) and a significantly lower epididymal adipocyte diameter. Basal net glycerol release was unchanged but beta-adrenergic-stimulated net glycerol release was higher with isolated adipocytes from fasted peroxisome proliferator-activated receptor alpha null mice compared with those of fasted wild-type mice. CONCLUSION:Peroxisome proliferator-activated receptor alpha deficiency prevents effects of fasting to increase adipocyte aquaglyceroporin 7 gene expression, and influences the regulation of inter-tissue glycerol flux after fasting via lowered adipocyte aquaglyceroporin 7 expression. Lowered gene expression of adipose triglyceride lipase and aquaglyceroporin 7 in peroxisome proliferator-activated receptor alpha null mice is not limiting for adipose triglyceride breakdown in vivo during fasting.
Authors: Amaia Rodríguez; Natalia R Moreno; Inmaculada Balaguer; Leire Méndez-Giménez; Sara Becerril; Victoria Catalán; Javier Gómez-Ambrosi; Piero Portincasa; Giuseppe Calamita; Graça Soveral; María M Malagón; Gema Frühbeck Journal: Sci Rep Date: 2015-07-10 Impact factor: 4.379
Authors: Andrea Markou; Lucas Unger; Mohammed Abir-Awan; Ahmed Saadallah; Andrea Halsey; Zita Balklava; Matthew Conner; Susanna Törnroth-Horsefield; Stuart D Greenhill; Alex Conner; Roslyn M Bill; Mootaz M Salman; Philip Kitchen Journal: Biochim Biophys Acta Biomembr Date: 2021-12-30 Impact factor: 3.747