Phytol-induced pathology in 2-hydroxyacyl-CoA lyase (HACL1) deficient mice. Evidence for a second non-HACL1-related lyase

作者：Mezzar Serena; De Schryver Evelyn; Asselberghs Stanny; Meyhi Els; Morvay Petruta L; Baes Myriam; Van Veldhoven Paul P^*

来源：Biochimica et Biophysica Acta-Molecular and Cell Biology of Lipids, 2017, 1862(9): 972-990.

DOI：10.1016/j.bbalip.2017.06.004

• a alpha-Oxidation
• Cerebronic acid
• Mouse model
• omega-Oxidation
• Peroxisomes
• Phytanic acid
• Refsum
• Thiamine

2-Hydroxyacyl-CoA lyase (HACL1) is a key enzyme of the peroxisomal alpha-oxidation of phytanic acid. To better understand its role in health and disease, a mouse model lacking HACL1 was investigated. Under normal conditions, these mice did not display a particular phenotype. However, upon dietary administration of phytol, phytanic acid accumulated in tissues, mainly in liver and serum of KO mice. As a consequence of phytanic acid (or a metabolite) toxicity, KO mice displayed a significant weight loss, absence of abdominal white adipose tissue, enlarged and mottled liver and reduced hepatic glycogen and triglycerides. In addition, hepatic PPAR alpha was activated. The central nervous system of the phytol-treated mice was apparently not affected. In addition, 20H-FA did not accumulate in the central nervous system of HACL1 deficient mice, likely due to the presence in the endoplasmic reticulum of an alternate HACL1-unrelated lyase. The latter may serve as a backup system in certain tissues and account for the formation of pristanic acid in the phytol-fed KO mice. As the degradation of pristanic acid is also impaired, both phytanoyl- and pristanoyl-CoA levels are increased in liver, and the omega-oxidized metabolites are excreted in urine. In conclusion, HACL1 deficiency is not associated with a severe phenotype, but in combination with phytanic acid intake, the normal situation in man, it might present with phytanic acid elevation and resemble a Refsum like disorder.

• 出版日期2017-9