分类: 生物学 >> 生物物理学 >> 生物物理、生物化学与分子生物学 提交时间: 2016-05-11
摘要: Methylation/demethylation of DNA, RNA and histone plays important roles in epigenetic functions. Formaldehyde is a significant factor participating in reversible and dynamic methylation of the biomacromolecules. As recently reported, memory formation and cognitive dysfunction are correlated with endogenous formaldehyde metabolism. Imbalance of formaldehyde metabolism affects DNA/RNA methylation and demethylation. Concentrations of endogenous formaldehyde are positively correlated with the severity of cognitive impairment of Alzheimer's patients in clinics. As an epidemiological survey shows, the levels of endogenous formaldehyde in elderly humans are negatively correlated with education years, suggesting that formaldehyde acts like a key factor in human learning and memory. "Live and learn" may mitigate the progression of age-related cognitive impairment resulted from imbalance of formaldehyde metabolism. Further investigation of endogenous formaldehyde involved in epigenetic modificaion and regulation should be carried out to understand the pathomechanism of cognition and cognitive impairment.
分类: 生物学 >> 生物物理学 >> 生物物理、生物化学与分子生物学 提交时间: 2016-05-11
摘要: It has been established that exposure in the hypomagnetic field (HMF), which is one of the environmental factor of outer space, has adverse effects on animal and human behavior and brain function. Thus, it is necessary to develop appropriate counteract strategy to avoid the HMF-induced risks to the health of the astronauts during long-term and long-distance manned space mission. However, the physical and mental effects of the HMF in details still await systematic evaluation and the underlying mechanism remains elusive, so far. In this study, we constructed an HMF animal rearing system (<500 nT) and examined the effects of one-month HMF exposure on the circadian behavior, pain response and emotions in adult male C57BL/6 mice (4 similar to 6 weeks old, (20 +/- 2) g). The control animals were reared in the geomagnetic field (GMF). The HMF-exposed animals exhibited a prolonged alteration of the circadian drinking rhythm and a decrease in general activity, accompanied with an increase in thermal hyperalgesia. But the HMF did not induce obvious depression-like and anxiety-related behaviors. The serum noradrenalin concentration in HMF-exposed mice significantly decreased. These findings indicate that the HMF disturbs the behavior rhythm and the function of endocrine system, which probably leads to the subsequently weakened activities of the animal.