Krinsky N I
Department of Biochemistry, School of Medicine, Tufts University, Boston, Massachusetts 02111, USA.
Ann N Y Acad Sci. 1998 Nov 20;854:443-7. doi: 10.1111/j.1749-6632.1998.tb09923.x.
Much effort has been expended in evaluating the relative antioxidant potency of carotenoid pigments in both in vitro and in vivo experiments. It is quite clear that in vitro, carotenoids can inhibit the propagation of radical-initiated lipid peroxidation, and thus fulfill the definition of antioxidants. When it comes to in vivo systems, it has been much more difficult to obtain solid experimental evidence that carotenoids are acting directly as biological antioxidants. In fact, under nonphysiological circumstances, carotenoids may act as prooxidants. These results can be modified by altering the oxidant stress, the cellular or subcellular system, the type of animal, and environmental conditions, such as oxygen tension. Results of this type raise the question as to whether it is still appropriate to group the carotenoids with such antioxidant vitamins as vitamin E and vitamin C. Thus, the biological properties of the carotenoids may be much more related to the products of the interaction of carotenoids with oxidant stress, that is, such breakdown products as apocarotenoids and retinoids.
在体外和体内实验中，人们已经付出了很多努力来评估类胡萝卜素色素的相对抗氧化能力。很明显，在体外，类胡萝卜素可以抑制自由基引发的脂质过氧化的传播，从而符合抗氧化剂的定义。而在体内系统中，要获得确凿的实验证据证明类胡萝卜素直接作为生物抗氧化剂则困难得多。事实上，在非生理条件下，类胡萝卜素可能充当促氧化剂。这些结果可以通过改变氧化应激、细胞或亚细胞系统、动物类型以及环境条件（如氧张力）来改变。这类结果引发了一个问题，即把类胡萝卜素与维生素E和维生素C等抗氧化维生素归为一类是否仍然合适。因此，类胡萝卜素的生物学特性可能与类胡萝卜素与氧化应激相互作用的产物，即类胡萝卜素和视黄醛等分解产物，有更大的关系。
