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Studying fatty aldehyde metabolism in living cells with pyrene-labeled compounds.

ABSTRACT: The lack of fatty aldehyde dehydrogenase function in Sjögren Larsson Syndrome (SLS) patient cells not only impairs the conversion of fatty aldehydes into their corresponding fatty acid but also has an effect on connected pathways. Alteration of the lipid profile in these cells is thought to be responsible for severe symptoms such as ichtyosis, mental retardation, and spasticity. Here we present a novel approach to examine fatty aldehyde metabolism in a time-dependent manner by measuring pyrene-labeled fatty aldehyde, fatty alcohol, fatty acid, and alkylglycerol in the culture medium of living cells using HPLC separation and fluorescence detection. Our results show that in fibroblasts from SLS patients, fatty aldehyde is not accumulating but is converted readily into fatty alcohol. In control cells, in contrast, exclusively the corresponding fatty acid is formed. SLS patient cells did not display a hypersensitivity toward hexadecanal or hexadecanol, but 3-fold lower concentrations of the fatty alcohol than the corresponding fatty aldehyde were needed to induce toxicity in SLS patient and in control cells.

SUBMITTER: Keller MA

PROVIDER: S-EPMC3371253 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Studying fatty aldehyde metabolism in living cells with pyrene-labeled compounds.

Keller Markus A MA Watschinger Katrin K Lange Karsten K Golderer Georg G Werner-Felmayer Gabriele G Hermetter Albin A Wanders Ronald J A RJ Werner Ernst R ER

Journal of lipid research 20120416 7

The lack of fatty aldehyde dehydrogenase function in Sjögren Larsson Syndrome (SLS) patient cells not only impairs the conversion of fatty aldehydes into their corresponding fatty acid but also has an effect on connected pathways. Alteration of the lipid profile in these cells is thought to be responsible for severe symptoms such as ichtyosis, mental retardation, and spasticity. Here we present a novel approach to examine fatty aldehyde metabolism in a time-dependent manner by measuring pyrene-l ...[more]

PMID: 22508945

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Project description:Dietary supplementation with natural chemoprotective agents is receiving considerable attention because of health benefits and lack of toxicity. In recent in vivo and in vitro experimental studies, diets rich in n-3 polyunsaturated fatty acids have been shown to provide significant anti-tumor action. In this investigation, the effects of control fatty acids (oleic acid (OA), linoleic acid (LA)) and n-3 PUFA, e.g., docosahexaenoic acid (DHA) on the uptake and metabolism of the carcinogenic polycyclic aromatic hydrocarbon, benzo[a]pyrene (BaP) was investigated in A549 cells, a human adenocarcinoma alveolar basal epithelial cell line. A549 cells activate BaP through the cytochrome P450 enzyme system to form reactive metabolites, a few of which covalently bind to DNA and proteins. Therefore, multiphoton microscopy spectral analysis combined with linear unmixing was used to identify the parent compound and BaP metabolites formed in cells, in the presence and absence of fatty acids. The relative abundance of select metabolites was associated with altered P450 activity as determined using ethoxyresorufin-O-deethylase activity in cells cultured in the presence of BSA-conjugated fatty acids. In addition, the parent compound within cellular membranes increases significantly in the presence of each of the fatty acids, with the greatest accumulation observed following DHA treatment. DHA treated cells exhibit significantly lower pyrene-like metabolites indicative of lower adducts including DNA adducts compared to control BSA, OA or LA treated cells. Further, DHA reduced the abundance of the proximate carcinogen BaP 7,8-dihydrodiol and the 3-hydroxybenzo[a]pyrene metabolites compared to other treatments. The significant changes in BaP metabolites in DHA treated cells may be mediated by the effects on the physicochemical properties of the membrane known to affect enzyme activity related to phase I and phase II metabolism. In summary, DHA is a highly bioactive chemo-protective agent capable of modulating BaP-induced DNA adducts.

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Studying fatty aldehyde metabolism in living cells with pyrene-labeled compounds.

Publications

Studying fatty aldehyde metabolism in living cells with pyrene-labeled compounds.

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