Lutein은 식물에서 발견되는 carotenoid 계열에 속하는 물질로 항산화 기능을 가지고 있는 것으로 널리 알려져 있지만, 호흡기 질환과 관련하여 아직까지 lutein의 효능과 작용 기작이 잘 알려져 있지 않다. Ovalbumin (OVA)으로 유도한 천식(asthma) 생쥐모델에서 lutein은 기도 과민성을 억제하였고, 기관지 폐포 세척액에서 OVA의 감작에 의하여 증가한 각종 염증성 지표들을 감소시켰다. 또한, OVA의 감작에 의하여 증가한 제2형 협조 T 세포(Th2 cell)의 증가된 반응을 약화시키는 결과를 볼 수 있었다. 본 실험에서 lutein이 ovalbumin (OVA)으로 유도한 천식 생쥐 모델에서 제 2형 협조 T세포의 싸이토카인과 유전자 발현을 조절할 수 있는 면역약리학적 기능을 할 수 있는 물질로서의 가능성이 있음을 확인할 수 있었다.
The general term flavonoids is often used to categorize a family of natural compounds that are highly abundant in all higher plants, and which in recent years have attracted scientific interest as therapeutics. Lutein is a xanthophyll and one of 600 known naturally occurring carotenoids. It is found in green vegetables such as spinach and kale, and has been demonstrated to exert anti-inflammatory activities. However, its anti-allergic effect in the Th1/Th2 immune response is poorly understood. In this study, we attempt to determine whether lutein regulates inflammatory mediators in an ovalbumin (OVA)-induced murine asthma model. To address this, mice were sensitized and challenged with OVA, and then treated with lutein before the last OVA challenge. Administration of lutein significantly suppressed the OVA-induced airway hyper-responsiveness. It also resulted in a significant alleviation of the infiltration of inflammatory cells into the bronchoalveolar lavage. Additionally, lutein attenuated the increased expression of Th2 responses in OVA-challenged mice. These results demonstrate that lutein is a potent inhibitor that reduces Th2 immune responses. Furthermore, they show that the immunopharmacological function is mediated by a pathway that involves and is regulated by Th2 immune response.
