Telomeres and Psychological Stress: Perspective on Psychopathologies.

INTRODUCTION: Telomeres are specialized DNA-protein complexes located at the ends of all chromosomes and act as a "molecular clock" to determine the replicative lifespan of the cells. Recent studies indicate that life-long exposure to stress, starting from the prenatal period, causes many diseases to emerge at an early age, and telomeres may be possible mediators in this process. This article aims to review the relationship between the stress-telomere-disease triad and the potential role of telomere dysfunction in psychopathologies in the light of current literature.

METHODS: A literature search was conducted along the lines of a narrative review. PubMed and Web of Science databases were used to identify all types of articles published from inception to January 2022. After the title/abstract search, articles available in full text and English were selected based on key findings, the applicability of the method used to test the hypothesis, limitations, interpretation of the results, and impact of the results in the field. A total of 73 records were included in this narrative review.

RESULTS: The fact that some age-related chronic diseases, such as cardiovascular diseases and type 2 diabetes, are seen more frequently and at an earlier age in certain psychopathologies including depression, bipolar disorder, and schizophrenia suggests that these disorders are premature ageing syndromes. Although there are some conflicting results in the literature, in line with this hypothesis, the presence of shortened telomeres reported in these psychopathologies and the impact of lifelong exposure to stress on this process are remarkable.

CONCLUSION: Many of the studies point to an association and do not tell much about the causality. Hence, the elucidation of the biological processes underlying the relationship between psychological stress, dysfunctional telomeres and complex, common age-related diseases, as well as psychiatric disorders is important and further studies are needed at the cellular level.