Document Detail


Both superficial and deep zone articular chondrocyte subpopulations exhibit the Crabtree effect but have different basal oxygen consumption rates.
MedLine Citation:
PMID:  20143333     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In the absence of in vivo measurements, the oxygen concentration within articular cartilage is calculated from the balance between cellular oxygen consumption and mass transfer. Current estimates of the oxygen tension within articular cartilage are based on oxygen consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic oxygen consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced oxygen consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of oxygen and glucose, which decrease with distance from the cartilage-synovial fluid interface. Thus, we tested the hypothesis that the oxygen consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree effect. The deep cells had a greater oxygen consumption than the superficial cells (V(max) of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 microm(3)/cell). Both populations expressed the Crabtree phenomena, with oxygen consumption increasing approximately 2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues.
Authors:
Hannah K Heywood; Martin M Knight; David A Lee
Related Documents :
19148583 - Online monitoring of oxygen in spinner flasks.
18426993 - Hypertension impairs postnatal vasculogenesis: role of antihypertensive agents.
6724723 - Lamellar germ cell processes: structures for possible interaction between germs cells a...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of cellular physiology     Volume:  223     ISSN:  1097-4652     ISO Abbreviation:  J. Cell. Physiol.     Publication Date:  2010 Jun 
Date Detail:
Created Date:  2010-04-07     Completed Date:  2010-04-21     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0050222     Medline TA:  J Cell Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  630-9     Citation Subset:  IM    
Copyright Information:
(c) 2010 Wiley-Liss, Inc.
Affiliation:
School of Engineering and Materials Science, Queen Mary University of London, London, UK. h.k.heywood@qmul.ac.uk
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adenosine Triphosphatases / metabolism
Animals
Cartilage, Articular / cytology*
Cattle
Cell Hypoxia / drug effects
Chondrocytes / cytology*,  drug effects,  enzymology,  metabolism*
Glucose / deficiency,  pharmacology
Glycolysis / drug effects
Kinetics
Mitochondrial Size / drug effects
Models, Biological
Oxygen Consumption* / drug effects
Grant Support
ID/Acronym/Agency:
080440/Z/06/Z//Wellcome Trust
Chemical
Reg. No./Substance:
50-99-7/Glucose; EC 3.6.1.-/Adenosine Triphosphatases

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Significance and outcome of left heart hypoplasia in fetal congenital diaphragmatic hernia.
Next Document:  Profilin-1 overexpression inhibits proliferation of MDA-MB-231 breast cancer cells partly through p2...