Investigating racing thoughts in insomnia: A neglected piece of the mood-sleep puzzle?

BACKGROUND: Cognitive arousal is thought to play a key role in insomnia disorder. However, although patients frequently complain about racing thoughts appearing at bedtime, studies have considered 'cognitive arousal' as a synonym of rumination and worry, but not as racing thoughts per se. The latter have been mainly linked to hypomanic/manic episodes of bipolar disorder (BD). Here we aimed at investigating self-reported racing thoughts in insomnia disorder, and their specific contribution to insomnia severity, as compared to worry and rumination. METHODS: 72 adults with insomnia disorder, 49 patients with BD in a hypomanic episode and 99 healthy individuals completed the Racing and Crowded Thoughts Questionnaire (RCTQ). Mood symptoms were assessed in patients with insomnia disorder. RESULTS: RCTQ scores were overall higher in insomnia disorder, especially in sleep-onset insomnia, compared to the hypomanic and healthy groups. Moreover, racing thoughts showed an increase in the evening and at bedtime in sleep-onset insomnia. Importantly, racing thoughts at bedtime, but not rumination and worry, were associated with insomnia severity. DISCUSSION: Our results are the first to show that racing thoughts is a transdiagnostic symptom in mood and sleep disorders. Racing thoughts, not only rumination and worry, might contribute to the maintenance of sleep difficulties in insomnia. Clinical trials' registration number: NCT04752254.

A Novel Long-Term ex vivo Model for Studying Vascular Calcification Pathogenesis: The Rat Isolated-Perfused Aorta.

The investigation of vascular calcification and its underlying cellular and molecular pathways is of great interest in current research efforts. Therefore, suitable assays are needed to allow examination of the complex calcification process under controlled conditions. The current study describes a new ex vivo model of isolated-perfused rat aortic tissue with subsequent quantification and vessel staining to analyze the calcium content of the aortic wall. A rat aorta was perfused ex vivo with control and calcification media for 14 days, respectively. The calcification medium was luminally perfused and induced a significant increase in calcium deposition within the media of the vessel wall detected alongside the elastic laminae. Perfusion with control medium induced no calcification. In addition, the mRNA expression of the osteogenic marker bone morphogenetic protein 2 (BMP-2) increased in aortic tissue after perfusion, while SM22α as smooth muscle marker decreased. This newly developed ex vivo model of isolated-perfused rat aorta is suitable for vascular calcification studies testing inducers and inhibitors of vessel calcification and studying signaling pathways within calcification progression.