Objectives: We aimed to investigate the effect of a symbiotic substance on symptoms of brain disorders and inflammation in the elderly.Methods: Forty-nine elders, both genders, assigned into two groups: S-group (synbiotic) and P-group (placebo). Evaluations at the beginning and at the end of the experiment: geriatric depressive symptoms scale-15 (GDS-15); mini-mental status examination (MMSE); % of body fat (%fat); serum IL-6, TNF-α and IL-10; serum diamine-oxidase (DAO), intestinal fatty-acid binding protein (IFABP), and lipopolysaccharide (LPS).Results: Both groups had reduced their %Fat, TNF-α, and DAO. The IL-6, GDS-15, and MMSE were increased in both groups. IL-10 was significantly increased only in the S-group, and LPS was significantly reduced only in the P-group. The GDS-15final was negatively explained by DAO, IL-10, TNF-α, %Fat, being woman, and being allocated in the P-group. The variables that positively explained the GDS-15final were the IL-6, the IFABP, and the LPS. MMSEfinal was positively associated with the IL-10, DAO, being woman, and being allocated in the P-group; and negatively associated with IL-6, TNF-α, %Fat, IFABP, and LPS.Conclusions: We found weak effects of symbiotic on depressive symptoms and more optimistic effects on cognition in apparently healthy elderly. Other studies, with individuals diagnosed with depressive morbidity or cognitive decline, are needed.Registration of Clinical Studies - REBEC (RBR-6qr9xx)].
Keywords: Cognitive impairment; Depressive symptoms; Elderly; Intestinal permeability; Synbiotics; Systemic inflammation.