Increased expression of Circadian Regulator CRY1 and CRY2 genes in long-term meditators

The human body undergoes various physical, metabolic, and behavioural changes that are governed by circadian rhythms. The Cryptochrome Circadian Regulator (CRY1 and CRY2) genes encode proteins critical for maintaining these rhythms. Increased expression of CRY genes supports circadian rhythm stability, contributing to overall physiological homeostasis. Meditation practice has been proposed as a potential modulator of CRY1 and CRY2 gene expression. This case-control study was conducted to compare the expression levels of CRY1 and CRY2 genes between experienced meditators and non-meditators. Thirty long-term, skilled meditators were recruited from meditation centres across Sri Lanka through a two-tier screening process, and age- and gender-matched non-meditators were selected from the local community. Sociodemographic data, including weekly exercise hours, were collected. Gene expression of CRY1 and CRY2 was analysed using reverse transcriptase polymerase chain reaction (RT-PCR), and relative gene expression levels were calculated using the 2-∆∆CT method. Of the 30 participants in each group, 63% (19 individuals) were male, with a mean age of 43 ± 9.92 years. Meditators had been practicing for an average of 6.80 ± 3.27 years, meditating approximately 5.82 ± 3.45 hours daily. Gene expression analysis revealed a significant upregulation of CRY1 (fold change = 1.9, p = 0.037) and CRY2 (fold change = 0.8, p = 0.05) in meditators compared to controls, suggesting enhanced circadian rhythm stability. Additionally, CRY1 expression was positively correlated with the duration of meditation practice (r = 0.377, p = 0.040), while CRY2 expression was significantly associated with weekly exercise hours (r = 0.256, p = 0.046). The upregulation of CRY genes observed in meditators suggests a stabilization of circadian rhythms, potentially contributing to improved physiological homeostasis. These findings highlight the potential of meditation to positively influence circadian biology.