Involvement of HPI Axis in the anti-stress activities of Hydrangeae Dulcis Folium in zebrafish.

Abstract

본연구에서는 ethalonic extract of Hydrangeae Dulcis Folium (EHDF)의스트레스예방효과를관찰하였다. 물리적스트레스유도방법인 Net handling stress (NHS)로스트레스를유도하여 EHDF가동물모델인제브라피쉬의행동변화와 cortisol 조절효능을확인하고자하였다. 6분간 EHDF에약욕후 NHS를유도하여 novel tank test, open field test 및 whole-body cortisol의수준을측정하였다.NHS를처리하지않은정상군과비교하여 NHS를유도한대조군에서 NTT와 OFT 결과, 대조군에서 meandering movement 및회전각, 부동시간의증가하고,총이동거리의감소하는행동변화가관찰되었다. 그러나 EHDF를 5-20 mg/L의농도로전처리한실험군에서 NHS 유도에의해나타나는행동변화가억제되었다(P<0.05). 또한NHS를처리하지않은정상군과비교하여 NHS를유도한대조군에서유의성있는 whole-body cortisol 수준의증가가관찰되었다(P<0.05).흥미롭게도 EHDF를 5-20 mg/L를 6분간전처리후 whole-body cortisol의수준을측정하였을때,대조군과비교하여유의성있게감소하는결과가관찰되었다(P<0.05). ACTHchallenge test결과, ACTH 처리에의한전신코티졸(whole-body cortisol) 분비증가가 EHDF에의해현저하게억제됨을확인할수있었다(P<0.05). 따라서EHDF는cortisol 분비량을억제하고, 스트레스를저하하는작용효과를나타내므로, 우울증, 불안장애, 피로증후군, 수면장애, 신경변성질병,스트레스성정신병에피소드와같은다양한스트레스성질환의치료제또는개선제등의개발에유용하게이용될수있다

In this study, the anti-stress effects of ethanolic extract of Hydrangeae Dulcis Folium (EHDF) were investigated. To determine the effects of EHDF on physical stress, changes in whole-body cortisol level or behavior were monitored in zebrafish. To induce physical stress, we used net handling stress (NHS). Fish were treated with EHDF for 6 min before exposing the animals to stress. And then, fish were used for evaluation through behavioral test including novel tank test or open field test, or sacrificed for collecting body fluid from whole-body. In result, increased anxiety-like behaviors in novel tank test and open field test under stress were recovered by treatment with EHDF at 5, 10 and 20 mg/L (P< 0.05). Moreover, compared with normal group which were not treated by NHS, whole-body cortisol level were significantly increased by treatment of NHS in control group. As compared with control group, pretreatment with EHDF at concentrations of 5, 10 and 20 mg/L for 6 min significantly prevented the increase of whole-body cortisol levels induced by NHS (P< 0.05). In addition, adrenocorticotropin hormone(ACTH) challenge studies showed that the EHDF completely blocked the effects of ACTH (0.2 IU/g, IP) on cortisol secretion. These results suggest that EHDF may be a good anti-stress candidate, and that its mechanism of action may be related to its positive effects on cortisol release.