Document Detail

Very long-chain fatty acids in peroxisomal disease.
MedLine Citation:
PMID:  1378993     Owner:  NLM     Status:  MEDLINE    
Fatty acids with from 24 to 28 carbon atoms (very long-chain fatty acids, VLCFA) are present in small amounts in all mammalian tissues. Even longer chain fatty acids with from 30 to 38 carbon atoms (ultra-long-chain fatty acids, ULCFA) are found in certain specialized tissues including retina, brain, and spermatozoa. In patients with inherited defects in peroxisomal structure and/or function, there is an accumulation of VLCFA in most tissues, while VLCFA and ULCFA levels are increased in brain. The most pronounced changes occur in those patients who have defects in peroxisomal assembly (Zellweger syndrome, infantile Refsum's disease, and neonatal adrenoleukodystrophy). In the brain of these individuals, ULCFA are distributed largely in molecular species of phosphatidylcholine with penta-, hexa-, and heptaenoic acids. In contrast, patients with X-linked adrenoleukodystrophy have increased levels of phosphatidylcholine with monoenoic rather than polyenoic ULCFA. A defect in a peroxisomal VLCFA CoA synthetase or ligase has been reported for these patients, but assembly of their peroxisomes is apparently normal. We speculate that ULCFA are normal products of carbon chain elongation. We have confirmed this by demonstrating the elongation of [1-14C]hexacosatetraenoic acid (26:4n-6) by rat brain in vivo to a series of longer chain tetraenoic acids with carbon chain lengths up to 34. Elongation to ULCFA can occur as well in non-neural tissues as shown by detection of labeled saturated and monoenoic fatty acids with up to 32 carbon atoms after incubation of normal and Zellweger syndrome fibroblasts with [2-14C] acetate. Increased labeling of VLCFA and ULCFA is observed in cells from patients with peroxisomal disorders. Our data suggest that ULCFA with up to at least 32 carbon atoms are formed normally, as a part of the elongation process in most mammalian tissues, and that control of carbon chain elongation is a major function of peroxisomes. Impairment of this function as occurs in peroxisomal disease results in the accumulation of VLCFA and ULCFA. The relative enrichment in normal tissues of ULCFA such as 32:6n-3 in ram and bull spermatozoa and 36:4n-6 in human and rat brain suggests a probable physiological role for this class of fatty acids in these tissues.
A Poulos; K Beckman; D W Johnson; B C Paton; B S Robinson; P Sharp; S Usher; H Singh
Related Documents :
17670843 - Influence of outer region mannosylphosphorylation on n-glycan formation by candida albi...
13942173 - Bacterial utilization of dodecyl sulfate and dodecyl benzene sulfonate.
6967693 - Cytochemical reactions in resting and activated t-lymphocytes.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Advances in experimental medicine and biology     Volume:  318     ISSN:  0065-2598     ISO Abbreviation:  Adv. Exp. Med. Biol.     Publication Date:  1992  
Date Detail:
Created Date:  1992-08-26     Completed Date:  1992-08-26     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0121103     Medline TA:  Adv Exp Med Biol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  331-40     Citation Subset:  IM    
Department of Chemical Pathology, Adelaide Medical Centre for Women and Children, South Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adrenoleukodystrophy / metabolism
Brain / metabolism
Child, Preschool
Fatty Acids / biosynthesis,  chemistry,  metabolism*
Infant, Newborn
Lipid Metabolism, Inborn Errors / classification,  metabolism*
Microbodies / metabolism*
Middle Aged
Refsum Disease / metabolism
Skin / metabolism
Zellweger Syndrome / metabolism
Reg. No./Substance:
0/Fatty Acids

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

Previous Document:  A role for the arachidonic acid cascade in fast synaptic modulation: ion channels and transmitter up...
Next Document:  The incidence of atrial arrhythmias during inferior wall myocardial infarction with and without righ...