Depression PUFAs

AA, EPA, DHA, GLA, DGLA, LXs and resolvins suppress lL-1, lL-2, lL-6, and TNF-a prodnction by T cells (110-112, 149, 176-180). This claim suggests that EFAs/PUFAs and their metabolites function as endogenous anti-inflammatory molecules and regulate immune response and thus are likely to be of benefit in obesity, insulin resistance, atherosclerosis, metabolic syndrome X, type 2 diabetes mellitus, CHD, depression, and Alzheimer s disease that are considered as diseases of low-grade systemic inflammation (1-8, 24, 120). Some beneficial actions of PUFAs in various inflammatory conditions are because of the formation of anti-inflammatory compounds such as lipoxins, resolvins, and neuroprotectin Dl. 

Depression is more likely to occur in individuals whose intake of PUFAs, especially of n-3 fatty acids, is lower (221). Pro-inflammatory cytokines might cause depressive illness (222). A significant decrease of i -3 fatty acids in plasma and/or in the membranes of red blood cells in subjects with depression has been reported (223-225). Because i -3 fatty acids suppress the production of IL-lfS, IL-2, IL-6, and TNF-a, this... 

Furthermore, a diet with low contents of FA may be involved in the development of insulin resistance, which suggests that an appropriate dietary intake of n-3 PUFA is considered protective against metabolic syndrome [183]. In addition, diverse psyquiatric impairs (depression, bipolar disorders, schizophrenia, autism) and neurodegenerative diseases such as Alzheimer disease have been associated to decreased blood levels of n-3 HUFA. Besides, there are many examples about the use of pol)nmsaturated FA as drugs. Thus, EPA has shown efficacy as adjunctive treatment, and in some cases as the only treatment in several psyquiatric disorders [184]. It is suggested that the potential of n-3 FA to prevent recurrence and metastasis of mammary cancer when used in adjuvant therapy is associated with a n-6 to n-3 ratio lower than 2 1 [185], On the other hand, fish intake is considered as a protective factor for preventing prostate cancer in addition, in humans low levels of ALA in mammary adipose tissue are associated with an increased risk of breast cancer in women [186]. 

The interaction between dietary PUFA and vitamin E levels was discussed recently by Sheffy and Shultz (1979). They reported that dogs fed diets high in PUFA but deficient in vitamin E and selenium rapidly developed a severely depressed lymphoproliferative response to mitogens. Vitamin E completely restored the response. The effect appears to be connected to preventing peroxidation of... 

Taonis et al. (2002) investigated the effects of dietary fatty acids on insulin signalling in mnscle tissne. For their study, 5-week-old male Wistar rats were fed one of three diets for 4 weeks control (high carbohydrate), n-6 PUFA (58% energy from safflower oil), or n-3 PUFA (39% energy from safflower oil and 19% energy from flsh oil). To determine effects of insulin stimulation, the rats were injected with insulin 7 min before termination. The results of this study showed that insulin-induced tyrosine phosphorylation of IR and IRS was similar in the muscle of the animals fed control and n-3 PUFA diets, but depressed in the animals fed the n-6 PUFA diet. 

---