Protective Effect of Nervonic Acid Against 6-Hydroxydopamine-Induced Oxidative Stress in PC-12 Cells.

Increased oxidative stress in the human brain is observed in neurodegenerative diseases such as Parkinson's disease (PD) and Alzheimer's disease (AD), and is considered to be a major cause of progression of these disease states. A very long-chain fatty acid, nervonic acid (NA), is the main fatty acid found in various sphingolipid species in the central nervous system. NA plays an important role in forming the plasma membrane's lipid bilayer and in maintaining normal myelin function. In this study, we examined the neuroprotective effect of NA against rat pheochromocytoma (PC-12) cells stimulated by 6-hydroxydopamine (6-OHDA), which served as a cell model of PD. PC-12 cells were pre-treated with different concentrations of NA for 48 h then subsequently co-treated with NA and 6-OHDA for 48 h to induce cellular oxidative stress. Cell viability was significantly increased by pre-treatment with a very low concentration of NA. The level of malondialdehyde, a marker of lipid peroxidation, was significantly decreased in NA-treated cells. The expression levels of superoxide dismutases (Mn SOD and Cu/Zn SOD) and γ-glutamylcysteine synthetase (GCLC), responsible for the synthesis of glutathione, were significantly increased, indicating that pre-treatment with NA activated the cellular antioxidant defense system. These results suggest that NA may play a role as a neuroprotective mediator in the brain.

Effects of the National School Lunch Program on Bone Growth in Japanese Elementary School Children.

The Japanese school lunch program with milk was designed to supply 33-50% of the necessary nutrients per day and 50% of the recommended dietary allowance for calcium, which is difficult to obtain from Japanese meals. Although this program contributes to the mental and physical development of children, the effect of these meals on the bone growth in children remains unknown. Therefore, we compared the effect of school lunch with milk on bone growth between elementary school children attending schools that did not enforce the school lunch with milk program (box-lunch group) and those attending schools that did enforce the program (school-lunch group). The study subjects included fourth-grade children during the 2009-2013 school years, of whom 329 children were in the school-lunch group and 484 children in the box-lunch group. The bone area ratio of the right calcaneus was evaluated using quantitative ultrasound (Benus III). Dietary intakes were assessed using brief self-administered diet history questionnaires. The subjects were asked to record their activities for 3 d so that the mean physical activity intensity and the time spent sleeping could be estimated. The bone area ratios (%) were significantly higher in the school-lunch group than in the box-lunch group (males 31.0±0.3 vs. 30.3±0.2; females 30.6±0.2 vs. 29.7±0.2). This tendency did not change even after adjustment for confounding factors associated with bone growth. The results suggest that nutrients supplied by the Japanese school lunch program contributed to increased bone growth in elementary school children.

Search for promotion factors of ultrasound bone measurement in Japanese males and pre/post-menarcheal females aged 8-14 years.

There is little evidence regarding the associations between bone growth and environmental factors among growing children, especially in Asians. The aim of this cross-sectional study was to search for the promotion factors of bone growth in Japanese children during growth. The study subjects were male (n=333) and pre/post-menarcheal female (n=179/n=68) school children aged 8-14 y. Bone status at the calcaneus was evaluated by quantitative ultrasound (Benus III), and the bone area ratio (BAR) was used as an evaluation index. Dietary intakes were assessed via brief self-administered diet history questionnaires. The participants were asked to record all of their activities for 3 d (2 weekdays and 1 holiday). They were also required to provide the most recent anthropometric measurement records at their schools and answer questions about the frequency of fractures and, for females, the length of time since menarche. Multiple regression analysis with dummy variables demonstrated that age, magnesium (more than the RDA), vitamin B(1) (more than the RDA), mean physical activity intensity per day (more than 1.7 METs), vitamin C (more than the RDA) and calcium (more than the RDA) were significantly positive influential factors of BAR for males. For premenarcheal females, age, vitamin A (more than the RDA), BMI, and mean physical activity intensity per day (more than 1.7 METs) were significantly positive influential factors of BAR, and for postmenarcheal females, only BMI and age were significantly positive influential factors of BAR. The results suggest that several manageable factors correlate with the bone mass, and the associations differ depending on gender and menarcheal status.