Circadian Rhythm and the Inflammasome
The research noted here, showing that innate immune responses are regulated by circadian rhythm, is interesting in the context of aging. Aging is characterized by both a complex disruption of circadian rhythm, alongside a growing state of constant inflammation, some of which is generated by maldaptive innnate immune reactions to the molecular damage that becomes more prevalent with age, such as mislocalized mitochondrial DNA resulting from mitochondrial dysfunction. To what degree is the chronic inflammation of aging made worse by issues with regulation of circadian rhythm? This is a question yet to be definitively answered.
New research the link between the immune system and the body's circadian rhythms often referred to as the body clock. Macrophages, immune cells that detect and respond to harmful substances, are able to trigger inflammation as a defence mechanism by assembling large complexes known as inflammasomes. Inflammasomes could be compared to 'smoke detectors' that will then alert the immune system of danger.
Activation of an inflammasome called NLRP3 was not found to be constant throughout the day but was regulated by the body's 24-hour circadian clock. This daily rhythm determines when macrophages are most efficient at detecting threats and when their energy levels peak to mount a response. The research also highlights a key role for mitochondria, the cell's energy producers, in driving these daily changes in immune activity. The study has significant implications for understanding and treating inflammatory diseases, such as arthritis, where overactive inflammasomes play a key role. Symptoms of such diseases often worsen in the morning, something this research may help explain.