Significance of vitamin A to brain function, behavior and learning

Abstract

Retinoid acid, the bioactive metabolite of vitamin A, is a potent signaling molecule in the brains of growing and adult animals, regulates numerous gene products, and modulates neurogenesis, neuronal survival and synaptic plasticity. Vitamin A deficiency (VAD) is a global health problem, yet our knowledge of its effects on behavior and learning is still emerging. Here we review studies that have implicated retinoids in learning and memory deficits of post-embryonic and adult rodent and songbird models. Dietary vitamin A supplementation improves learning and memory in VAD rodents and can ameliorate cognitive declines associated with normal aging. Songbird studies examine the effects of retinoid signaling on vocal/auditory learning and are uniquely suited to study the behavioral effects of VAD because the neural circuitry of the song system is discrete and well understood. Similar to human speech acquisition, avian vocal learning proceeds in well-defined stages of template acquisition, rendition and maturation. Local blockade of retinoic acid production in the brain or excess dietary retinoic acid results in the failure of song maturation, yet does not affect prior song acquisition. Together these results yield significant insights into the role of vitamin A in maintaining neuronal plasticity and cognitive function in adulthood.

Neurotransmitters Level in Hypothyroid Male Albino Rats after Isotretinoin Treatment

“…Numerous behavioral studies in animal models have pointed to behavioral changes in rodents when the balance of RA is disrupted, either from exposure to excess or deficiency (Bremner et al, 2012;Olson and Mello, 2010). Finding in our study suggested that isotretinoin treatment in both healthy (Iso group) and hypothyroid animals H+Iso may affect brain monoamines system, providing a possible biological mechanism by which isotretinoin treatment could lead to depressive disorders.…”

DNA Fingerprinting Profile and Quality Control Standardization of Folklore Medicinal Plant Exacum lawii

“…38 Vitamin A (retinoic acid), it is a bioactive metabolite and a potent signalling molecule in the brains which modulates neurogenesis, neuronal survival, synaptic plasticity and regulates numerous gene products. 39 Vitamin E is the major component of the cell antioxidant defence system and has numerous important roles in the body due to its antioxidant activity. 40 The most abundant macroelements detected were Calcium (Ca), Potassium (K), Iron (Fe) and Sodium (Na).…”

Antioxidant Vitamins and Their Use in Psychiatry

“…Retinoik asit, özellikle erken embryogenezde önemli bir sinyal molekülüdür. [25] Vitamin A ve türevleri, retinoid reseptörleri aracılığı ile gen transkripsiyonunu düzenleyerek hücresel süreçlerde rol oynar. Bu reseptörler, retinoik asit reseptörleri (RAR) ve retinoid X reseptörleri (RXR) olmak üzere 2 gruba ayrılır.…”

“…[86][87][88] Diğer yandan retinoik asit sinyal yolaklarının gelişmekte olan ve erişkin beynindeki plastisiteyi etkiliyor olması, vitamin E'nin hücre sinyalizasyonu ve proliferasyonu üzerine olan etkileri ve vitamin C'nin gen ekspresyonu üzerine düzenleyici etkilerinin olabileceğine ilişkin veriler bu vitaminlerin normalden yüksek düzeylerinin ileride henüz öngöre-mediğimiz sonuçları olabileceğini akla getirmektedir. [25,41,63] Diğer yandan bu vitaminlerin eksikliklerine karşı da uyanık olmak gerekmektedir. Özellikle bazı psikiyatrik hastalıklarda hastaların sınırlı yeme tercihleri veya beslenme yetersizlikleri sebebi ile antioksidan vitaminler dahil birçok vitamin ve mineralin düşük düzeyleri söz konusu olabilir.…”