Change in the Expression of Occludin, a Gene for Blood-Brain Barrier by Phytoestrogens in Hippocampus of Rat Model for Menopause

폐경기모델 백서 해마에서 식물성 에스트로젠에 의한 뇌-혈액장벽 유전자 occludin 발현의 변화

  • Published : 2006.06.01

Abstract

To elucidate the effect of phytoestrogens on the prevention of neurodegenerative disease in postmenopausal women, the expression of occludin which build up the blood-brain barrier was examined in hippocampus following oral administration of estrogen (E2), genistein, diadzein or combination of genistein and diadzein in ovariectomized (OVX) female rats. E2 significantly increased occludin mRNA level in OVX rat hippocampus, suggesting that estrogen is a physiological regulator for structural integrity of the blood-brain barrier in hippocampus. Following isoflavone diet for 4 weeks, there was significant increase in occludin mRNA level in hippocampus, suggesting that isoflavone diet may be effective for protection of structural integrity of blood-brain barrier in hippocampus from degenerative changes in estrogen deficiency.

폐경기 여성은 동령 남성보다 퇴행적 뇌질환의 빈도가 유의적으로 높으며 이를 예방개선하기 위한 목적으로 에스트로젠 대체요법이 시행되고 있으나 유방암과 자궁암 유발 위험성이 제시되고 있어 콩류 등에 다량 함유되어 있는 phytoestrogen류인 isoflavone을 이용한 대체요법 개발이 활발하다. 밀착결합에 의해 제공되는 혈액-뇌확산장벽은 뇌의 항상성 조절에 중요한 역할이 있으며 다양한 뇌질환에서 변형이 일어난다. 본 연구는 난소절제 백서 모델에서 폐경기 여성의 퇴행적 뇌질환의 원인으로 혈액-뇌 확산장벽의 변형과 isoflavone의 효과를 검색하였다. 8주령 암컷 백서를 난소절제한 후 4주간 estrogen또는 isoflavone을 투여한 후 해마조직에서 밀착결합 유전자의 일종인 occludin발현을 조사하였다. E2는 occludin mRNA발현을 유의하게 증가시켰으며, genistein, diadzein등의 isoflavone투여 시 occludin mRNA발현이 유의적으로 증가하였다. Occludin은 폐경기 여성 호발성 퇴행성 뇌질환의 병인유전자 가능성이 제시되며 isoflavone은 occludin의 발현을 증가시켜 에스트로젠 결핍에 따른 혈액-뇌 확산장벽의 변형을 예방하는 효과가 있는 것으로 사료된다.

Keywords

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