[Temporal order deterioration and circadian disruption with age. 2. Systemic mechanisms and correction].

Part 2 of the present review highlights the impact of aging on mechanisms involved in response of the circadian system to different photic and non-photic factors, especially zeitgebers. Promising strategies to prevent age-dependent circadian disruption using internal and external factors that may entrain circadian rhythms are presented. In particular, benefits of bright light, melatonin and other chronobiotics, the circadian body temperature rhythm, physical activity and regular feeding schedules to preserve the temporal order of aged organisms are discussed, emphasizing especially a personalized approach based on the assessment of individual overt rhythms parameters.