Refsum disease: Difference between revisions
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==Biological sources of phytanic acid== |
==Biological sources of phytanic acid== |
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In ruminant animals, the gut fermentation of consumed plant materials liberates [[phytol]], a constituent of [[chlorophyll]], which is then converted to [[phytanic acid]] and stored in fats.<ref> |
In ruminant animals, the gut fermentation of consumed plant materials liberates [[phytol]], a constituent of [[chlorophyll]], which is then converted to [[phytanic acid]] and stored in fats.<ref name="pmid9819701">{{cite pmid|9819701}}</ref> Although humans cannot derive significant amounts of phytanic acid from the consumption of chlorophyll present in plant materials, it has been proposed that the great apes (bonobos, chimpanzees, gorillas, and orangutans) can derive significant amounts of [[phytanic acid]] from the hindgut fermentation of plant materials.<ref name="pmid20932325">{{cite pmid|20932325}}</ref> |
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==See also== |
==See also== |
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Revision as of 11:39, 29 October 2010
| Refsum disease | |
|---|---|
| Specialty | Neurology  |
Refsum disease, also known as classic or adult Refsum disease, heredopathia atactica polyneuritiformis, phytanic acid oxidase deficiency and phytanic acid storage disease,[1][2][3][4] is an autosomal recessive[5] neurological disease that results from the over-accumulation of phytanic acid in cells and tissues. It is one of several disorders named after Norwegian neurologist Sigvald Bernhard Refsum (1907–1991).[6][7] It is a peroxisomal disorder and has been described as being one of the leukodystrophy family of disorders, although it does not affect white matter to the same extent as other family members.
Classification
This form of Refsum disease, the adult form, may be divided into two subtypes: "adult Refsum disease 1" and "adult Refsum disease 2". When the disease stems from a mutation in the phytanoyl-CoA hydroxylase (PAHX aka PHYH) gene, it is the "adult, 1" type; when stemming from a mutation in the peroxin-7 (PEX7) gene, it is the "adult, 2" type.[1]
Refsum disease should not be confused with infantile Refsum disease, a peroxisome biogenesis disorder resulting from deficiencies in the catabolism of very long chain fatty acids and branched chain fatty acids (such as phytanic acid) and plasmalogen biosynthesis.[1][8]
Characteristics
Individuals with Refsum disease present with neurologic damage, cerebellar degeneration, and peripheral neuropathy. Onset is most commonly in childhood/adolescence with a progressive course, although periods of stagnation/remission occur. Symptoms also include night blindness, ataxia, scaly skin (ichthyosis), difficulty hearing, and eye problems including cataracts.
Cause
Refsum disease is caused by the impaired alpha-oxidation of branched chain fatty acids resulting in buildup of phytanic acid and its unsaturated fatty acid derivatives in the plasma and tissues. This may be due to deficiencies of phytanoyl-CoA hydroxylase or peroxin-7 activity. In general, Refsum disease is caused by PHYH mutations.
Treatment
Individuals with Refsum disease are commonly placed on a phytanic acid-restricted diet and avoid the consumption of fats from ruminant animals and certain fish.[9][10] Recent research has shown that CYP4 isoform enzymes could help reduce the over-accumulation of phytanic acid in vivo.[11] Plasmapheresis is another medical intervention used to treat patients.
Biological sources of phytanic acid
In ruminant animals, the gut fermentation of consumed plant materials liberates phytol, a constituent of chlorophyll, which is then converted to phytanic acid and stored in fats.[12] Although humans cannot derive significant amounts of phytanic acid from the consumption of chlorophyll present in plant materials, it has been proposed that the great apes (bonobos, chimpanzees, gorillas, and orangutans) can derive significant amounts of phytanic acid from the hindgut fermentation of plant materials.[13]
See also
External links
References
- ^ a b c Online Mendelian Inheritance in Man (OMIM): 266500
- ^ Freedberg; et al. (2003). Fitzpatrick's Dermatology in General Medicine (6th ed.). McGraw-Hill. p. 499. ISBN 0071380760.
{{cite book}}: Explicit use of et al. in:|author=(help) - ^ James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology (10th ed.). Saunders. p. 564. ISBN 0721629210.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 1-4160-2999-0.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ Attention: This template ({{cite pmid}}) is deprecated. To cite the publication identified by PMID 18336720, please use {{cite journal}} with
|pmid=18336720instead. - ^ Refsum S (1945). "Heredoataxia hemeralopica polyneuritiformis - et tidligere ikke beskrevet familiært syndrom? En foreløbig meddelelse". Nordisk Medicin (in Norwegian). 28: 2682–6.
- ^ Refsum S (1946). "Heredopathia atactica polyneuritiformis. A familial syndrome not hitherto described. A contribution to the clinical study of hereditary diseases of the nervous system". Acta psych. neur. (Suppl.38): 1–303.
- ^ Online Mendelian Inheritance in Man (OMIM): 266510
- ^ National Institutes of Health. "Synonym(s): Phytanic Acid Storage Disease, Heredopathia Atactica Polyneuritiformis <Internet>". Retrieved 8 July 2007.
- ^ Baldwin, R.J. et. al 2010. The effectiveness of long-term dietary therapy in the treatment of adult Refsum disease. J Neurol Neurosurg Psychiatry 81, 954-957.
- ^ Xu F, Ng VY, Kroetz DL, de Montellano PR (2006). "CYP4 isoform specificity in the omega-hydroxylation of phytanic acid, a potential route to elimination of the causative agent of Refsum's disease". J. Pharmacol. Exp. Ther. 318 (2): 835–9. doi:10.1124/jpet.106.104976. PMID 16707724.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ Attention: This template ({{cite pmid}}) is deprecated. To cite the publication identified by PMID 9819701, please use {{cite journal}} with
|pmid=9819701instead. - ^ Attention: This template ({{cite pmid}}) is deprecated. To cite the publication identified by PMID 20932325, please use {{cite journal}} with
|pmid=20932325instead.