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Aging is a process characterized by deterioration of the homeostasis of various physiological systems; although being a process under influence of multiple factors, the mechanisms involved in aging are not well understood. Here we investigated the effect of a (PhSe)2-supplemented diet (1ppm, 4weeks) and swimming exercise (1% of body weight, 20min per day, 4weeks) on proteins related to glial cells activation, apoptosis and neuroprotection in the hypothalamus of old male Wistar rats (27month-old). Old rats had activation of astrocytes and microglia which was demonstrated by the increase in the levels of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule 1 (Iba-1) in hypothalamus. A decrease of B-cell lymphoma 2 (Bcl-2) and procaspase-3 levels as well as an increase of the cleaved PARP/full length PARP ratio (poly (ADP-ribose) polymerase, PARP) and the pJNK/JNK ratio (c-Jun N-terminal kinase, JNK) were observed. The levels of mature brain-derived neurotrophic factor (mBDNF), the pAkt/Akt ratio (also known as protein kinase B) and NeuN (neuronal nuclei), a neuron marker, were decreased in the hypothalamus of old rats. Old rats that received a (PhSe)2-supplemented diet and performed swimming exercise had the hypothalamic levels of Iba-1 and GFAP decreased. The combined treatment also increased the levels of Bcl-2 and procaspase-3 and decreased the ratios of cleaved PARP/full length PARP and pJNK/JNK in old rats. The levels of mBDNF and NeuN, but not the pAkt/Akt ratio, were increased by combined treatment. In conclusion, a (PhSe)2-supplemented diet and swimming exercise promoted neuroprotection in the hypothalamus of old rats, reducing apoptosis and glial cell activation., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Selenium is an essential trace element for human health and has received attention for its role as a nutrient. The combination of exercise and nutrients has been proposed to promote health. The aim of this study was to determine the effects of a diet supplemented with diphenyl diselenide (PhSe)2 and swimming exercise on memory of middle-aged rats. Male Wistar rats (12months) received standard diet chow supplemented with 1ppm of (PhSe)2 for 4weeks. Rats were submitted to swimming training (20min per day for 4weeks). After 4weeks, memory was evaluated in the object recognition test (ORT) and in the object location test (OLT). The hippocampal levels of phosphorylated cAMP-response element-binding protein (CREB) were determined. The results of the present study demonstrated that the association of (PhSe)2-supplemented diet and swimming exercise improved short-term memory, long-term memory and spatial learning, and this effect was not related to the increase in hippocampal p-CREB levels in middle-age rats. This study also revealed that middle-aged rats in the swimming exercise group had the best performance in short- and long-term memory. In conclusion, we demonstrated that swimming exercise, (PhSe)2-supplemented diet or the association of these factors improved learning and memory functioning. The hippocampal levels of CREB were not directly related to the benefits of swimming exercise and (PhSe)2-supplemented diet association in memory of middle-aged rats., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The aim of the present study was to evaluate the effects of diphenyl diselenide (PhSe)2 supplemented diet (10ppm) associated to the administration of caffeine (15mg/kg; i.g.) for 30days on the novel object recognition memory in middle-aged rats. The present findings showed that (PhSe)2-supplemented diet enhanced short-term memory, but not long-term memory, of middle-aged rats in the novel object recognition task. The (PhSe)2 supplemented diet associated with caffeine administration improved long-term memory, but did not alter short-term memory, impaired in middle-aged rats. Daily caffeine administration to middle-aged rats had no effect on the memory tasks. Diet supplemented with (PhSe)2 plus caffeine administration increased the number of crossings and rearings reduced in middle-aged rats. Caffeine administration plus (PhSe)2 diets were effective in increasing the number of rearings and crossings, respectively, in middle-aged rats, [(3)H] glutamate uptake was reduced in hippocampal slices of rats from (PhSe)2 and caffeine plus (PhSe)2 groups. In addition, animals supplemented with (PhSe)2 showed an increase in the pCREB/CREB ratio whereas pAkt/Akt ratio was not modified. These results suggest that the effects of (PhSe)2 on the short-term memory may be related to its ability to decrease the uptake of glutamate, influencing the increase of CREB phosphorylation. (PhSe)2-supplemented diet associated to the administration of caffeine improved long-term memory impaired in middle-aged rats, an effect independent of CREB and Akt phosphorylation., (Copyright © 2014 Elsevier Inc. All rights reserved.)