Circadian Clocks – Role of Endogenous Rhythms in Health and Illness From Bedside to Bench … and Back

by Dr. Dominic Landgraf, Clinic for Psychiatry and Psychotherapy, Ludwig-Maximilians-Universität München

will take place on Tuesday, October 24th, 2023 from 16:00 to 17:00 hours in CBBM Building, Ground Floor, Seminar Room Levi-Montalcini.

Host: Prof. Henrik Oster
Institute of Neurobiology

Abstract: Endogenous circadian clocks in harmonization with environmentally determined 24-hour rhythms of day and night determine the activity of virtually all processes in our body. On the one hand, this favors the adaptation of behavior and neuronal and metabolic processes to the respective demands of different times of day, and on the other hand, within the organism, the synchronization of these encompassing and interconnected processes with each other. Because of this ubiquitous impact, it seems unsurprising that disturbances of the circadian system can contribute to the development of mental and physical illnesses and to the comorbid occurrence of both. As a basis for our research we take, for one, patients of our clinic suffering from alcohol addiction and depressive symptomatology, and, for another, people from the normal population suffering from excess weight, each of whom reported deficits in the maintenance of diurnal rhythmic regularity. From this, we first investigate in mice the basics that confirm causal links between disturbed circadian clocks and the facilitation of abnormal alcohol drinking behavior, depression- and anxiety-like behavior, and also metabolic conditions such as obesity and prediabetic states, and their combinations. Moreover, our animal research shows that restoring disrupted circadian rhythms can significantly reduce both behavioral and metabolic deficits simultaneously. We used these findings as an opportunity to conduct pilot studies to examine the efficacy of behavioral therapies for adherence to daily personalized routines, first, in withdrawing patients with alcohol addiction and depression and, second, in overweight individuals. The results of these studies show that following daily structure schedules helps alcohol-dependent patients to remain abstinent during the first and most critical weeks of withdrawal. In addition, they demonstrate that study participants with excess weight can lose significant body weight within a few weeks, even though they report no reductions in their food choices or amounts. The combination of our basic and clinical research thus shows that disturbed circadian clocks can contribute to the development of disorders, but also, more importantly, that conversely, stabilization of disturbed rhythms can be successfully used therapeutically for both mental and metabolic disorders.