Organization of energy transfer and feedback regulation in oxidative muscle cells
type: CreativeWork
description: Recently, it has been hypothesized that in oxidative muscle cells the mitochondria and ATPases form tight complexes, termed as the intracellular energetic units (ICEUs). At present the structure and molecular basis of the ICEUs are unclear and therefore an object of active research. Aims of the study: 1) To assess influence of alteration of the intracellular structure on mentioned units by hypercontraction in normal cardiomyocytes and in HL-1 cells, 2) to confirm existence of ICEUs by mathematical modeling of real experimental data, 3) to investigate whether ICEUs exist also in human heart atrium and in musculus gluteus medius (MGM), 4) to investigate whether these units may in MGM disintegrate during osteoarthritis. Results of the study: Differently from cardiomyocytes, where mitochondria and CaMgATPases are organized into ICEUs which ensure effective energy transfer and feedback signaling between these structures via specialized pathways mediated by CK and AK isoforms and direct adenine nucleotide channeling, the ICEUs do not exist in HL-1 cells due to less organized energy metabolism. Ca2+-induced hypercontraction leads in normal cardiomyocytes to the decreased direct transfer of ADP from ATPases to the mitochondria, thus to impairment of ICEU function. Mathematical modelling shows that in oxidative muscle cells diffusion restrictions of metabolites are not distributed uniformly within cardiac muscles, but are localized in certain areas, which supports the ICEU hypothesis. Energy metabolism in human atria and MGM cells is organized similarly to that in oxidative muscles − in the form of the ICEUs. Pathogenesis of OA involves disintegration of the ICEUs in association with dysfunction of CK-phosphotransfer system and increased diffusion of exogenous ADP to mitochondria. Hiljuti püstitati hüpotees, mille kohaselt oksüdatiivsetes lihasrakkudes moodustavad mitokondrid ja ATPaasid komplekse, e. rakusiseseid energeetilisi üksusi (RSEÜd). Praeguseks pole veel selge nend…
abstract: Recently, it has been hypothesized that in oxidative muscle cells the mitochondria and ATPases form tight complexes, termed as the intracellular energetic units (ICEUs). At present the structure and molecular basis of the ICEUs are unclear and therefore an object of active research. Aims of the study: 1) To assess influence of alteration of the intracellular structure on mentioned units by hypercontraction in normal cardiomyocytes and in HL-1 cells, 2) to confirm existence of ICEUs by mathematical modeling of real experimental data, 3) to investigate whether ICEUs exist also in human heart atrium and in musculus gluteus medius (MGM), 4) to investigate whether these units may in MGM disintegrate during osteoarthritis. Results of the study: Differently from cardiomyocytes, where mitochondria and CaMgATPases are organized into ICEUs which ensure effective energy transfer and feedback signaling between these structures via specialized pathways mediated by CK and AK isoforms and direct adenine nucleotide channeling, the ICEUs do not exist in HL-1 cells due to less organized energy metabolism. Ca2+-induced hypercontraction leads in normal cardiomyocytes to the decreased direct transfer of ADP from ATPases to the mitochondria, thus to impairment of ICEU function. Mathematical modelling shows that in oxidative muscle cells diffusion restrictions of metabolites are not distributed uniformly within cardiac muscles, but are localized in certain areas, which supports the ICEU hypothesis. Energy metabolism in human atria and MGM cells is organized similarly to that in oxidative muscles − in the form of the ICEUs. Pathogenesis of OA involves disintegration of the ICEUs in association with dysfunction of CK-phosphotransfer system and increased diffusion of exogenous ADP to mitochondria. Hiljuti püstitati hüpotees, mille kohaselt oksüdatiivsetes lihasrakkudes moodustavad mitokondrid ja ATPaasid komplekse, e. rakusiseseid energeetilisi üksusi (RSEÜd). Praeguseks pole veel selge nend…
author: Eimre, Margus
date published: 2009-03-10T13:34:34Z
date modified: 2026-07-24T06:23:29Z
provider: University of Tartu
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Tartu