Do sex hormones or hormone therapy modify the relation of n-3 fatty acids with incident depressive symptoms in postmenopausal women? The MESA Study

n-3 PUFA Improve Emotion and Cognition during Menopause: A Systematic Review

Women show an increased risk of cognitive impairment and emotional disorders, such as anxiety and depression, when approaching menopause. Data on risk and protection factors have yielded robust evidence on the effects of lifestyle factors, such as diet, in preserving emotional and cognitive functioning. This review focused on the effects of omega-3 polyunsaturated fatty acids (n-3 PUFA) on anxiety, depression, and cognition during the menopausal transition. This systematic review considered all articles published until 31 December 2021, and the search was performed on two databases, PubMed and Scopus. The fields of interest were "menopause", "n-3 PUFA" and "emotional and cognitive aspects". Out of the 361 articles found on PubMed and 283 on Scopus, 17 met inclusion criteria. They encompassed 11 human and 6 animal studies. Most studies reported relieved depressive symptoms in relation to n-3 PUFA intake. While controversial results were found on anxiety and cognition in humans, n-3 PUFA consistently reduced anxiety symptoms and improved cognition in animal studies. Taken together, n-3 PUFA intake shows beneficial effects on emotional and cognitive behaviours during menopause transition. However, further investigations could increase knowledge about the effectiveness of n-3 PUFA on psychological well-being in this delicate period of feminine life.

DHA-Enriched Fish Oil Ameliorates Deficits in Cognition Associated with Menopause and the APOE4 Genotype in Rodents

Female APOE4 carriers have a greater predisposition to developing Alzheimer’s disease (AD) compared to their male counterparts, which may partly be attributed to menopause. We previously reported that a combination of menopause and APOE4 led to an exacerbation of cognitive and neurological deficits, which were associated with reduced brain DHA and DHA:AA ratio. Here, we explored whether DHA-enriched fish oil (FO) supplementation mitigated the detrimental impact of these risk factors. Whilst DHA-enriched fish oil improved recognition memory (NOR) in APOE4 VCD (4-vinylcyclohexene diepoxide)-treated mice (p < 0.05), no change in spatial working memory (Y-maze) was observed. FO supplementation increased brain DHA and nervonic acid and the DHA:AA ratio. The response of key bioenergetic and blood−brain barrier related genes and proteins provided mechanistic insights into these behavioural findings, with increased BDNF protein concentration as well as mitigation of aberrant Erβ, Cldn1 and Glut-5 expression in APOE4 mice receiving fish oil supplementation (p < 0.05). In conclusion, supplementation with a physiologically relevant dose of DHA-enriched fish oil appears to offer protection against the detrimental effects of menopause, particularly in “at-risk” APOE4 female carriers.

Depression During and After the Perimenopause: Impact of Hormones, Genetics, and Environmental Determinants of Disease

Vulnerability to depression is increased across the menopause transition and in the early years after the final menstrual period. Clinicians should systematically screen women in this age group; if depressive symptoms or disorder are present, treatment of depression should be initiated. Potential treatments include antidepressants for moderate to severe symptoms, psychotherapy to target psychological and interpersonal factors, and hormone therapy for women with first-onset major depressive disorder or elevated depressive symptoms and at low risk for adverse effects. Behavioral interventions can improve physical activity and sleep patterns.

Effects of n-3 PUFA enriched and n-3 PUFA deficient diets in naïve and Aβ-treated female rats

Depression is one of the most common psychiatric diseases and the prevalence of depressive symptoms in women is almost twice compared to men, although the reasons of this gender difference are not fully understood yet. Recently, soluble Aβ_1-42 peptide has been receiving great importance in the development of depression, also since depression is highly comorbid with Alzheimer's disease and other neurodegenerative illnesses. Accordingly, we have previously shown that central Aβ injection is able to elicit depressive-like phenotype in male rats. In the present study, we reproduced for the first time the Aβ-induced depressive-like model in female rats, evaluating behavioural and neurochemical outcomes. Moreover, we studied the effect of lifelong exposure to either n-3 PUFA enriched or n-3 PUFA deficient diet, in female rats, both intact and after central Aβ administration. Our results confirmed the Aβ-induced depressive-like profile also in female rats. Moreover, chronic exposure to n-3 PUFA deficient diet led to highly negative alterations in behavioural and neurochemical parameters, while lifelong exposure to n-3 PUFA enriched diet was able to restore the Aβ-induced depressive-like profile in female rats. In conclusion, the Aβ-induced depressive-like profile was reversed by n-3 PUFA supplementation, indicating a possible therapeutic role of n-3 PUFA in the treatment of the burden of depressive disorders.

Focus on fatty acids in the neurometabolic pathophysiology of psychiatric disorders

Continuous research into the pathophysiology of psychiatric disorders, such as major depressive disorder (MDD), posttraumatic stress disorder (PTSD), and schizophrenia, suggests an important role for metabolism. This narrative review will provide an up-to-date summary of how metabolism is thought to be involved in the pathophysiology of these psychiatric disorders. We will focus on (I) the important role of fatty acids in these metabolic alterations, (II) whether fatty acid alterations represent epiphenomena or risk factors, and (III) similarities and dissociations in fatty acid alterations between different psychiatric disorders. (Historical) epidemiological evidence links fatty acid intake to psychiatric disorder prevalence, corroborated by altered fatty acid concentrations measured in psychiatric patients. These fatty acid alterations are connected with other concomitant pathophysiological mechanisms, including biological stress (hypothalamic-pituitary-adrenal (HPA)-axis and oxidative stress), inflammation, and brain network structure and function. Metabolomics and lipidomics studies are underway to more deeply investigate this complex network of associated neurometabolic alterations. Supplementation of fatty acids as disease-modifying nutraceuticals has clinical potential, particularly add-on eicosapentaenoic acid (EPA) in depressed patients with markers of increased inflammation. However, by interpreting the observed fatty acid alterations as partly (mal)adaptive phenomena, we attempt to nuance translational expectations and provide new clinical applications for these novel neurometabolic insights, e.g., to predict treatment response or depression recurrence. In conclusion, placing fatty acids in context can contribute to further understanding and optimized treatment of psychiatric disorders, in order to diminish their overwhelming burden of disease.