1. Biological responses to environmental and social stress
In modern stressful societies, stress-related illnesses have become recognized as major public health problems. Especially, prolonged and consecutive stress, such as social, physiological and psychical one, have been recognized a key etiology of stress-related illnesses. We are therefore investigating about physiological changes under exposing to environmental and social stress using animal models
(1) We are interested in the mechanism of stress stimulated development of breast cancer. Combined effect of estrogen metabolites and catecholamines on the development of breast cancer are investigated.
(2) In group-housed mice, individual variability in the stress response was observed. Therefore, we established a method to distinguish individual mice in the group during the dark phase. Now we are investigating behavioral phenotype in social stressed mice.
2. Effect of environmental and social stress on biorhythm
Most living things have a circadian rhythm and are under the influence of its cycle. Recently, differences of biological reactions related to circadian rhythms have been studied and applied to many fields, including clinical pharmacology, sitology, nutrition and food science. In general, we humans are exposed to many environmental chemicals in our active phases. However, dosing of chemicals in the non-clinical safety studies using experimental animals such as mice are usually conducted in the light period, which is the inactive phase for the animals. We are investigating any differences in biological responses to chemicals between the light and dark periods (inactive and active phases).
3. How can we prevent some environmental and social stress related diseases ?
We are investigating some foods/drugs, which can prevent our health from some diseases induced by environmental and social stressors. For this purpose, it is quite important topics for understanding their benefit or toxic effects to investigate absorption, metabolism, and detoxification of endogenous and exogenous factors. Especially, we are investigating preventive effect of flavonoids on stress related breast cancer.