1.
Vitamin A: its many roles-from vision and synaptic plasticity to infant mortality.
Dowling, JE
Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology. 2020;(3):389-399
Abstract
The recognition that a dietary factor is essential to maintain good and sensitive vision as well as overall health goes back over 3,000 years to the ancient Egyptians. With the discovery of the vitamins at the turn of the twentieth century, fat-soluble vitamin A was soon shown to be the essential factor. In the first half of the twentieth century, the role vitamin A plays in vision, as precursor to the light-sensitive visual pigment molecules in the photoreceptors was elegantly worked out, especially by George Wald and his colleagues. Beginning in the 1960s, with the recognition of the active metabolite of vitamin A, its acid form now called retinoic acid, the roles of vitamin A in maintaining overall health of an organism began to be explored, and this research continues to this day. Receptors activated by retinoic acid, the RARs and RXRs have been shown to regulate gene transcription in a surprisingly wide variety of biological processes from early growth and development to the maintenance of epithelial tissues in many organs, the regulation of the immune system, and even the modulation of synaptic function in the brain involved in mechanisms underlying memory and learning. Therapeutic uses for retinoic acid have been developed, including one for a specific form of leukemia. The story is by no means complete and it is likely more surprises await with regard to this remarkable molecule.
2.
Neuro-, Cardio-, and Immunoplasticity: Effects of Early Adversity.
Pakulak, E, Stevens, C, Neville, H
Annual review of psychology. 2018;:131-156
Abstract
The relationship between early adversity and outcomes across the lifespan is apparent in a striking range of measures. Evidence suggests that many of these outcomes can be traced to the impacts of early adversity on multiple and integrated biological systems mediated by the brain. In this review, we integrate empirical and theoretical advances in the understanding of relationships among the brain and the functions of the endocrine, autonomic, and immune systems. We emphasize the effects of environmental experiences related to caregiver relationships because it is these experiences, in particular, that shape regulatory and threat response systems in ways that increase vulnerability and may underlie the wide range of poor outcomes associated with early adversity. Thus, we metaphorically extend the concept of plasticity to highlight our goal of a broader consideration of these interconnected mechanisms. We conclude by discussing implications for neurobiologically informed interventions that can potentially ameliorate the broad and costly effects of early adversity.