Vitamin A as a key regulator of obesity & its associated disorders: Evidences from an obese rat model.

During the last century, vitamin A has evolved from its classical role as a fat-soluble vitamin and attained the status of para-/autocrine hormone. Besides its well-established role in embryogenesis, growth and development, reproduction and vision, vitamin A has also been implicated in several other physiological processes. Emerging experimental evidences emphasize adipose tissue as an active endocrine organ with great propensity to continuous growth (throughout life). Due to various genetic and lifestyle factors, excess energy accumulates in adipose tissue as fat, resulting in obesity and other complications such as type 2 diabetes, hypertension, and cardiovascular disease. Recent in vitro and in vivo studies have shed light on vitamin A metabolites; retinaldehyde and retinoic acid and participation of their pathway proteins in the regulation of adipose tissue metabolism and thus, obesity. In this context, we discuss here some of our important findings, which establish the role of vitamin A (supplementation) in obesity and its associated disorders by employing an obese rat model; WNIN/Ob strain.