ω-3 and major depression: a review.

BACKGROUND: The World Health Organization estimates that major depression affects about 350 million people all over the world and reports this disorder as the major contributor to the global burden of diseases. Despite the well-defined symptomatology, major depression is a heterogeneous psychiatric disorder whose pathophysiology is not clearly established. Although several treatments are available, most depressed patients do not achieve the complete remission of symptoms. Factors linked to the persistence of the disorder have been investigated, particularly those related to the way of life. Moreover, it has been suggested that nutritional aspects may influence its development. Among them, a diet rich in ω-3 has been associated with a reduced risk of major depression, although its deficiency is associated with depressive disorders. METHODS: This review provides a general view about evidences of the use of ω-3 in major depression cases. RESULTS: Several studies have demonstrated beneficial effects of ω-3 in the prevention and treatment of major depression. However, not all the results have shown significant statistical benefits. CONCLUSIONS: More studies are necessary to clarify detailed mechanisms of the antidepressant effects of ω-3 and may explain the source of contradictions in results published until the moment.

Energy metabolism and behavioral parameters in female mice subjected to obesity and offspring deprivation stress.

This study aimed to evaluate the behavioral and energy metabolism parameters in female mice subjected to obesity and offspring deprivation (OD) stress. Eighty female Swiss mice, 40 days old, were weighed and divided into two groups: Control group (control diet, n = 40) and Obese group (high-fat diet, n = 40), for induction of the animal model of obesity, the protocol was based on the consumption of a high-fat diet and lasted 8 weeks. Subsequently, the females were subjected to pregnancy, after the birth of the offspring, were divided again into the following groups (n = 20): Control non-deprived (ND), Control + OD, Obese ND, and Obese + OD, for induction of the stress protocol by OD. After the offspring were 21 days old, weaning was performed and the dams were subjected to behavioral tests. The animals were humanely sacrificed, the brain was removed, and brain structures were isolated to assess energy metabolism. Both obesity and OD led to anhedonia in the dams. It was shown that the structures most affected by obesity and OD are the hypothalamus and hippocampus, as evidenced by the mitochondrial dysfunction found in these structures. When analyzing the groups separately, it was observed that OD led to more pronounced mitochondrial damage; however, the association of obesity with OD, as well as obesity alone, also generated damage. Thus, it is concluded that obesity and OD lead to anhedonia in animals and to mitochondrial dysfunction in the hypothalamus and hippocampus, which may lead to losses in feeding control and cognition of the dams.