The neurotoxic effects of vitamin A and retinoids

An Acad Bras Cienc. 2015 Aug;87(2 Suppl):1361-73. doi: 10.1590/0001-3765201520140677. Epub 2015 Aug 4.

Abstract

Vitamin A (retinol) and its congeners - the retinoids - participate in a panoply of biological events, as for instance cell differentiation, proliferation, survival, and death, necessary to maintain tissue homeostasis. Furthermore, such molecules may be applied as therapeutic agents in the case of some diseases, including dermatological disturbances, immunodeficiency, and cancer (mainly leukemia). In spite of this, there is a growing body of evidences showing that vitamin A doses exceeding the nutritional requirements may lead to negative consequences, including bioenergetics state dysfunction, redox impairment, altered cellular signaling, and cell death or proliferation, depending on the cell type. Neurotoxicity has long been demonstrated as a possible side effect of inadvertent consumption, or even under medical recommendation of vitamin A and retinoids at moderate to high doses. However, the exact mechanism by which such molecules exert a neurotoxic role is not clear yet. In this review, recent data are discussed regarding the molecular findings associated with the vitamin A-related neurotoxicity.

Publication types

  • Review

MeSH terms

  • Dietary Supplements / adverse effects*
  • Humans
  • Mitochondria / drug effects
  • Nervous System Diseases / chemically induced*
  • Oxidative Stress / drug effects
  • Retinoids / adverse effects*
  • Retinoids / metabolism
  • Vitamin A / adverse effects*
  • Vitamin A / metabolism
  • Vitamins / adverse effects*
  • Vitamins / metabolism

Substances

  • Retinoids
  • Vitamins
  • Vitamin A