Fish oil and depression: The skinny on fats

Abstract

Depression is the leading cause of disability worldwide, and even though many forms of therapy exist, about one third of patients treated with conventional antidepressants do not experience a response. For these reasons, new approaches to treat depression, including fish oil, are being investigated. Fish oil is known to have many beneficial side effects, and clinical trials demonstrate that supplementation with fish oil is beneficial in the management of depression. Fish oil contains omega-3 polyunsaturated fatty acids (PUFA), and there are several mechanisms by which PUFAs are thought to induce an antidepressant effect, including anti-inflammatory action and direct effects on membrane properties. This review will analyze and evaluate the clinical trials surrounding fish oil use in the treatment of depression, and will also review the likely sites of action of PUFAs at the cell membrane with special attention being placed on lipid rafts and G-proteins.

Gut Reactions: Breaking Down Xenobiotic–Microbiome Interactions

“…Functional alterations following plant sterol ester, oat b-glucan, and atorvastatin were also noted in this study, using microbial and host-derived metabolites in the serum metabolome as a readout (Ryan et al, 2017). Polyunsaturated fatty acids (PUFAs) are thought to exert an antidepressant effect, possible via their antiinflammatory properties (Burhani and Rasenick, 2017). Omega-3 PUFAs also have important cardioprotective and neurodevelopmental properties and support the function and aging of the central nervous system (Pusceddu et al, 2016).…”

N-3 polyunsaturated fatty acids promote astrocyte differentiation and neurotrophin production independent of cAMP in patient-derived neural stem cells

“…N-3 PUFAs play fundamental roles in brain structure and function. Accumulating evidence has implicated deficiency of n-3 PUFA (EPA and DHA) in the etiology of depression and n-3 PUFA in the treatment of MDD [13, 15]. Multiple mechanisms might underlie the protective/therapeutic effect of n-3 PUFAs on MDD [13–17].…”

“…Accumulating evidence has implicated deficiency of n-3 PUFA (EPA and DHA) in the etiology of depression and n-3 PUFA in the treatment of MDD [13, 15]. Multiple mechanisms might underlie the protective/therapeutic effect of n-3 PUFAs on MDD [13–17]. Decrease in astrocyte count and GFAP expression are often seen in MDD post-mortem studies [32, 33] [34, 35] [50].…”

“…Many studies have suggested antidepressant efficacy for omega-3 fatty acids (n-3 PUFA) in MDD [13–17], and n-3 PUFAs might evoke an antidepressant paradigm in culture cells and animal models [13]. The mechanisms of n-3 PUFA antidepressant action remain poorly documented, but include inhibition of the production of proinflammatory cytokines and maintenance of neuronal membrane stability and fluidity [13, 18]. Most efforts to characterize the mechanism of action of n-3 PUFAs have been done in animals and cell lines.…”

Low Omega-3 intake is associated with high rates of depression and preterm birth on the country level

“…For MDD, it appears that insufficient Omega-3 levels can: (1) alter hormonal signaling and neurotransmitter function (e.g. serotonin, dopamine, glucocorticoid, lipid receptor, and endocannabinoid mediated signaling), (2) increase neuro-inflammatory processes, and (3) impair neurogenesis [43][44][45] . For PTB, insufficient Omega-3 levels can: (1) have broad inflammatory effects, (2) increase placental trophoblast cell death, and (2) intensify the biochemical conversion of omega-6 PUFA into utero-tonic (labor inducing) prostaglandins [46][47][48] .…”