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Is autophagy an elective strategy to protect neurons from dysregulated cholesterol metabolism?

ABSTRACT: The balance of autophagy, apoptosis and necroptosis is crucial to determine the outcome of the cellular response to cholesterol dysregulation. Cholesterol plays a major role in regulating the properties of cell membranes, especially as regards their fluidity, and the regulation of its biosynthesis influences the shape and functions of these membranes. Whilst dietary cholesterol can easily be distributed to most organs, the central nervous system, whose membranes are particularly rich in cholesterol, mainly relies on de novo synthesis. For this reason, defects in the biosynthesis of cholesterol can variably affect the development of central nervous system. Moreover, defective synthesis of cholesterol and its intermediates may reflect both on structural cell anomalies and on the response to inflammatory stimuli. Examples of such disorders include mevalonate kinase deficiency, and Smith-Lemli-Opitz syndrome, due to deficiency in biosynthetic enzymes, and type C Niemann-Pick syndrome, due to altered cholesterol trafficking across cell compartments. Autophagy, as a crucial pathway dedicated to the degradation of cytosolic proteins and organelles, plays an essential role in the maintenance of homeostasis and in the turnover of the cytoplasmic material especially in the presence of imbalances such as those resulting from alteration of cholesterol metabolism. Manipulating the process of autophagy can offer possible strategies for improving neuronal cell viability and function in these genetic disorders.

SUBMITTER: Piscianz E

PROVIDER: S-EPMC6352582 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Is autophagy an elective strategy to protect neurons from dysregulated cholesterol metabolism?

Piscianz Elisa E Vecchi Brumatti Liza L Tommasini Alberto A Marcuzzi Annalisa A

Neural regeneration research 20190401 4

The balance of autophagy, apoptosis and necroptosis is crucial to determine the outcome of the cellular response to cholesterol dysregulation. Cholesterol plays a major role in regulating the properties of cell membranes, especially as regards their fluidity, and the regulation of its biosynthesis influences the shape and functions of these membranes. Whilst dietary cholesterol can easily be distributed to most organs, the central nervous system, whose membranes are particularly rich in choleste ...[more]

PMID: 30632494

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Is autophagy an elective strategy to protect neurons from dysregulated cholesterol metabolism?

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Is autophagy an elective strategy to protect neurons from dysregulated cholesterol metabolism?

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