Effect of the ethanolic extract of cactus pear (Opuntia ficus-indica) fruit on net handling stress in zebrafish

Abstract

백년초 에탄올 추출물이 net handling stress를 유도한 제브라피쉬에 미치는 영향

스트레스는 자율신경계 및 내분비 기능의 장애를 유발한다. 뿐만 아니라 만성 스트레스는 우울증 및 공황 장애과 같은 신경계 질환의 원인이 되기도 한다. 본 연구에서는 Opuntia ficus-indica(OF70E)를 70% EtOH로 추출하고, 그 추출물을 용매분획하여 hexane, EtOAc, n-BuOH, 및 물분획물을 얻었다. OF70E의 항스트레스 활성을 관찰하기 위하여 net handling stress(NHS) 유도 후 행동변화 및 whole-body cortisol level을 측정하였다. OF70E의 조추출물 또는 분획물로 전처리한 후 open field test 및 novel tank test를 이용하여 행동 변화를 관찰한 결과, NHS에 의하여 변화된 행동변화가 정상 수준으로 억제되는 것으로 나타내었다. Whole-body cortisol level, 또한 실험에 사용된 시료의 모든 농도에서 대조군에 비해 감소하는 결과가 관찰되었다. 이상의 결과는 OF70가 항스트레스 효과를 가지고 있으며, OF70E 및 그 분획물은 항스트레스에 대한 치료제로 개발될 수 있음을 시사하는 것이라고 사료된다. 향후 분획 에서 분리된 유효성분으로부터 동일한 연구를 통하여 우수한 항스트레스 물질을 개발할 수 있을 것으로 보인다.

To determine the anti-stress effects of Opuntia ficus-indica(OF70E) and its fractions on physical stress, we monitored endocrine changes such as whole-body cortisol level and behavioral changes in zebrafish. To induce physical stress, we used net handling stress (NHS). In results, compared with normal group which did not induce by NHS, whole-body cortisol level were significantly increased by treatment with NHS in control group (p<0.05). To examine behavioral changes induced by NHS in zebrafish, we conducted open field test (OFT) or novel tank test (NTT) after the induction of NHS and effect of pretreatment of OF70E or its fractions. As results of OFT, compared with normal group which did not induce by NHS, distance moved were significantly decreased by treatment of NHS in control group (p<0.05). Interestingly, pretreatment with OF70E blocked decreases of distance moved increased by NHS (p<0.05). And meandering movement, immobility and turn angle were significantly increased by NHS as compared with normal group (p<0.05). However, pretreatment with OF70E prevented the increases of meandering movement immobility and turn angle (p<0.05). And pretreatment with OF70E at all concentrations for 6min significantly prevented the increase of whole-body cortisol levels induced by NHS. As compared with control group, pretreatment with EtOAc fraction, n-BuOH fraction or water fraction of OF70E significantly prevented the increase of whole-body cortisol levels induced by NHS except hexane fraction (p<0.05). As results of NTT, compared with normal group which were untreated by NHS, duration in top, distance moved, velocity and zone transition were significantly decreased by treatment of NHS in control group (p<0.05). Interestingly, pretreatment with water fraction of OF70E blocked decreases of duration in top, distance moved, velocity and zone transition increased by NHS (p<0.05). In addition, meandering movement, immobility and turn angle were significantly increased by NHS as compared with normal group. And pretreatment with its H2O fractions at concentrations of 15-60 mg/L for 6min significantly prevented the increase of whole-body cortisol levels induced by NHS. In conclusion these results suggest that the pretreatment of OF70E and its fraction may prevent stress responses, such as the behavioral and endocrine changes.