1. Cortico-limbic functional connectivity mediates the effect of early life stress on suicidality in bipolar depressed 5-HTTLPR*s carriers
- Author
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Alessandro Serretti, Sara Poletti, Francesco Benedetti, Cristina Colombo, Cristina Lorenzi, Mattia Mascia, Benedetta Vai, Vai, B., Serretti, A., Poletti, S., Mascia, M., Lorenzi, C., Colombo, C., Benedetti, F., Vai B., Serretti A., Poletti S., Mascia M., Lorenzi C., Colombo C., and Benedetti F.
- Subjects
Adult ,Serotonin ,Bipolar Disorder ,Early stress ,Genotype ,Bipolar disorder ,Population ,Precuneus ,Amygdala ,03 medical and health sciences ,0302 clinical medicine ,Adverse Childhood Experiences ,Early stre ,mental disorders ,Medicine ,Humans ,education ,Child ,Promoter Regions, Genetic ,Serotonin transporter ,Anterior cingulate cortex ,Serotonin Plasma Membrane Transport Proteins ,Connectivity ,education.field_of_study ,Polymorphism, Genetic ,biology ,Depression ,business.industry ,medicine.disease ,Magnetic Resonance Imaging ,030227 psychiatry ,Psychiatry and Mental health ,Clinical Psychology ,Suicide ,medicine.anatomical_structure ,nervous system ,5-HTTLPR ,Endophenotype ,biology.protein ,business ,Neuroscience ,psychological phenomena and processes ,030217 neurology & neurosurgery - Abstract
Background In bipolar disorder (BD) the risk of suicide in adult life can be influenced by the interaction of adverse childhood experiences with the serotonin transporter polymorphism (5-HTTLPR). The cortico-limbic connectivity is a candidate endophenotype for the disorder, also related to suicidality and affected by the 5-HT system. Methods In 64 (*s carriers = 41; l/l = 23) depressed BD patients, we explored the effect of 5-HTTLPR on corticolimbic functional connectivity (FC) during emotional processing, and the role of FC in moderating/mediating the effect of early stressful events on suicidality among 5-HTTLPR groups, by implementing Generalized Structural Equation Model. Results 5-HTTLPR affects FC between amygdala (Amy) and anterior cingulate cortex (ACC), temporal pole, putamen/thalamus, and precuneus. The short allele was associated to a more inefficient corticolimbic connectivity. In 5-HTTLPR*s carriers, but not in l/l, the Amy-ACC functional coupling mediated the relationship between stress load and current suicidality. Limitations Patients were not drug-naive, and the recruitment took place in a single center, thus raising the possibility of population stratifications. The sample size is relatively small, but our findings can provide the background for replication study in independent and larger datasets. Conclusions Our results confirm the link between the 5-HTT promoter polymorphism and susceptibility to stress in BD, and suggest that cortico-limbic functional connectivity mediates these effects. This pattern could identify a vulnerability factor for the exacerbation of mood episodes after stressful life events particularly relevant in *s carriers.
- Published
- 2019