No abstract

Alzheimer's disease (AD) is characterized by the deposition of aggregated amyloid-beta (Aβ), which triggers a cellular stress response called the unfolded protein response (UPR). The UPR signaling pathway is a cellular defense system for dealing with the accumulation of misfolded proteins but switches to apoptosis when endoplasmic reticulum (ER) stress is prolonged. ER stress is involved in neurodegenerative diseases including AD, but the molecular mechanisms of neuronal apoptosis and inflammation by Aβ-induced ER stress to exercise training are not fully understood. Here, we demonstrated that treadmill exercise (TE) prevented PS2 mutation-induced memory impairment and reduced Aβ-42 deposition through the inhibition of β-secretase (BACE-1) and its product, C-99 in cortex and/or hippocampus of aged PS2 mutant mice. We also found that TE down-regulated the expression of GRP78/Bip and PDI proteins and inhibited activation of PERK, eIF2α, ATF6α, sXBP1 and JNK-p38 MAPK as well as activation of CHOP, caspase-12 and caspase-3. Moreover, TE up-regulated the expression of Bcl-2 and down-regulated the expressions of Bax in the hippocampus of aged PS2 mutant mice. Finally, the generation of TNFα and IL-1α and the number of TUNEL-positive cells in the hippocampus of aged PS2 mutant mice was also prevented or decreased by TE. These results showed that TE suppressed the activation of UPR signaling pathways as well as inhibited the apoptotic pathways of the UPR and inflammatory response following Aβ-induced ER stress. Thus, therapeutic strategies that modulate Aβ-induced ER stress through TE could represent a promising approach for the prevention or treatment of AD.

This study was conducted to investigate relationships and gender differences in dietary supplement (DS) and oriental supplement (OS) prevalence as well as anti-doping awareness during training and the game period. Korea National Sport University athletes (343 male and 136 female) participated in this study and completed DS and OS practice and anti-doping awareness questionnaires. Forty-six percent of athletes used DS during the training period, and there was significantly higher DS use in females (53%) compared to males (43%) (P < 0.05). Twenty-eight percent of athletes used OS, and there was significantly higher OS use in females (35%) than males (26%) (P < 0.05) during the training period. The primary reason of DS use was to supply energy both in males (36%) and females (28%). The main reason for male athletes' OS use was to supply energy (41%). Meanwhile, the reasons for female athletes' OS use were to supply energy (23%), to maintain health (19%), and to improve recovery ability (20%), which showed a significant gender difference (P < 0.05). Athletes rated their perceived degree of satisfaction, perceived importance, and beliefs in efficacy of DS and OS use all over 50% during the training period, and no gender differences were detected. In a comparison between athletes educated about anti-doping (at least more than one time) and non-received athletes, DS and OS use during the training period was 2.30 (1.47-3.60) and 1.71 (1.03-2.82), respectively. DS and OS use immediately before the game period was 2.38 (1.50-3.80) and 3.99 (1.20-13.28), respectively. Elite athletes' anti-doping education was highly related to increased DS use during the training period and immediately before the game. Although elite athletes use various DS and OS during the training period and before the game period, doping education for elite athletes is related with DS and OS use during the training period and before the game.