Association between visceral adipose tissue and major depressive disorder across the lifespan: A scoping review.

OBJECTIVES: Increasing evidence supports a bidirectional relationship between major depressive disorder (MDD) and obesity, but the role of visceral adipose tissue (VAT) as a measure of obesity in relation to MDD is not well understood. Here we review literature investigating the link between MDD and VAT in terms of biomarkers, sex differences, and aging. METHODS: PubMed, EMBASE, PsycINFO, and CINAHL searches were conducted on December 11, 2020. No date or language limits were imposed. Major concepts searched were Depressive Disorder linked with Adipose Tissue, White, Hypothalmo-Hypophyseal System, and Pituitary-Adrenal System in addition to keywords. A final set of 32 items meeting criteria for inclusion. RESULTS: Converging biological evidence suggests a significant bidirectional relationship between VAT and MDD across the lifespan. In adulthood, greater VAT was associated with increased risk for depression, especially in vulnerable groups such as individuals who are overweight/obese, postmenopausal women, and individuals with comorbid medical or psychiatric illness. In older adults, sarcopenia had an impact on the relationship between abnormal VAT and risk of depression. Additionally, sex differences emerged as a potential factor affecting the strength of the association between VAT and depression. CONCLUSIONS: Elucidating the pathophysiological mechanisms associated with increased rates of depression in obese individuals will be crucial for developing specific treatment strategies that seek to improve outcomes in individuals with comorbid depression and obesity. Moreover, identifying age- and sex-specific risk factors may contribute to a more personalized medicine approach, thereby improving the quality of clinical care.

The effect of aging on facial emotion recognition in bipolar disorder.

OBJECTIVE: Convergent data point to an exaggerated negativity bias in bipolar disorder (BD), and little is known about whether people with BD experience the 'positivity effect' with increasing age. METHOD: This is a cross sectional study of 202 participants with BD aged 18-65, and a sample (n = 53) of healthy controls (HCs). Participants completed the CANTAB Emotion Recognition Task (ERT). Using analysis of variance, we tested for a main effect of age, diagnosis, and an interaction of age x diagnosis on both negative and positive conditions. RESULTS: We observed increased accuracy in identifying positive stimuli in the HC sample as a function of increasing age, a pattern that was not seen in participants with BD. Specifically, there was a significant diagnosis by age cohort interaction on ERT performance that was specific to the identification of happiness, where the Later Adulthood cohort of HCs was more accurate when identifying happy faces relative to the same cohort of BD patients. CONCLUSION: Later life looks different for people with BD. With an aging population globally, gaining a clearer picture of the effects of recurrent mood dysregulation on the brain will be critical in guiding efforts to effectively optimize outcomes in older adults with BD.

Functional genomics in the study of mind-body therapies.

BACKGROUND: Mind-body therapies (MBTs) are used throughout the world in treatment, disease prevention, and health promotion. However, the mechanisms by which MBTs exert their positive effects are not well understood. Investigations into MBTs using functional genomics have revolutionized the understanding of MBT mechanisms and their effects on human physiology. METHODS: We searched the literature for the effects of MBTs on functional genomics determinants using MEDLINE, supplemented by a manual search of additional journals and a reference list review. RESULTS: We reviewed 15 trials that measured global or targeted transcriptomic, epigenomic, or proteomic changes in peripheral blood. Sample sizes ranged from small pilot studies (n=2) to large trials (n=500). While the reliability of individual genes from trial to trial was often inconsistent, genes related to inflammatory response, particularly those involved in the nuclear factor-kappa B (NF-κB) pathway, were consistently downregulated across most studies. CONCLUSION: In general, existing trials focusing on gene expression changes brought about by MBTs have revealed intriguing connections to the immune system through the NF-κB cascade, to telomere maintenance, and to apoptotic regulation. However, these findings are limited to a small number of trials and relatively small sample sizes. More rigorous randomized controlled trials of healthy subjects and specific disease states are warranted. Future research should investigate functional genomics areas both upstream and downstream of MBT-related gene expression changes-from epigenomics to proteomics and metabolomics.