Effects of long-term meditation practice on expression of CRY1 and CRY2 genes related to circadian rhythm:a case-control study

Abstract

Introduction: Many physical, metabolic and behavioural changes in the human body follow a circadian rhythm. Cryptochrome circadian regulator (CRY) 1 and 2 genes encode circadian proteins important for circadian rhythmicity. Up-regulated CRY genes ensure the stability of the circadian rhythm which contribute to maintenance of homeostasis in the body. Practice of meditation has been suggested to up-regulate the expression of CRY1 and CRY2 genes. This case-control study compared expression of CRY1 and CRY2 genes between long-term, skilled meditators and non-meditators. Methods: Thirty meditators were recruited from meditation centres in different parts of Sri Lanka following a two-tier screening process and age and gender matched non-meditators were recruited from the community. Socio-demographic characteristics including exercise hours per week were collected. Expression of CRY1 and CRY2 genes was assessed via reverse transcriptase polymerase chain reaction. Relative gene expression was determined using the 2-∆∆CT method. Independent sample t-test was used to compare the mean fold changes of the expression of genes between meditators and controls. Pearson correlation was used to determine the bivariate relationships between continuous variables...