[Effects of light intensity on cleaning away heat property of Viola yedoensis].

The current study was conducted to explore the effects of light intensity in cultivating environment on the cleaning away heat property of Viola yedoensis. In the present study, we established the acute inflammation model of ICR mice by injecting carrageenan. We compared the effects of V. yedoensis grown under different light intensities(100%, 80%, 50%, 35% and 5% of full sunlight) on mice body temperature, thermal radiation and the swelling degree of foot tissue before and after modeling observing by thermal infrared imaging technique and weighing method. The changes of energy metabolism related enzymes in liver were detected by enzyme-linked immunosorbent assay(ELISA). In addition, the effects of V. yedoensis grown under different light intensities on human lung cancer cell A549 proliferation were explored with MTT method. The results showed that the body temperature of all groups of mice in V. yedoensis group were significantly lower than that of the blank group, except 5% full sunlight group, and the body temperature declined in positive proportion to light intensity. V. yedoensis group could alleviate foot swelling, reduce SDH activity in liver tissue(especially 100% full sunlight group and 80% full sunlight group were significantly lower than model group), and the degree of alleviating and reducing was positively correlated with light intensity. There was no significant difference in the activity of Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase in liver tissue among treatments. The contents of IL-1β, IL-6, TNF-α, PGE_2 in foot tissue of mice in V. yedoensis groups were significantly lower than those in model group. Among them, the lowest levels of IL-1β, IL-6, TNF-α, PGE_2 were found in 80% full sunlight group, and there was no significant difference in TNF-α among different groups. The effects of V. yedoensis aqueous extract on A549 cell line proliferation inhibition rate increased with the light intensities of V. yedoensis cultivating environment. And the effects of V. yedoensis grown under 100% of full sunlight showed significantly higher A549 cell line proliferation inhibition rate compared with other groups(P<0.05). In summary, the light intensity of V. yedoensis cultivating environment is positively correlated with the cleaning away heat property of V. yedoensis, which conforms to the "light-cold and heat property" hypothesis,The V. yedoensis should be planted under full light according.