Arnhold Jürgen
Medical Faculty, Institute of Medical Physics and Biophysics, Leipzig University, 04107 Leipzig, Germany.
Antioxidants (Basel). 2021 Nov 12;10(11):1805. doi: 10.3390/antiox10111805.
In our organism, mucous surfaces are important boundaries against the environmental milieu with defined fluxes of metabolites through these surfaces and specific rules for defense reactions. Major mucous surfaces are formed by epithelia of the respiratory system and the digestive tract. The heme peroxidases lactoperoxidase (LPO), myeloperoxidase (MPO), and eosinophil peroxidase (EPO) contribute to immune protection at epithelial surfaces and in secretions. Whereas LPO is secreted from epithelial cells and maintains microbes in surface linings on low level, MPO and EPO are released from recruited neutrophils and eosinophils, respectively, at inflamed mucous surfaces. Activated heme peroxidases are able to oxidize (pseudo)halides to hypohalous acids and hypothiocyanite. These products are involved in the defense against pathogens, but can also contribute to cell and tissue damage under pathological conditions. This review highlights the beneficial and harmful functions of LPO, MPO, and EPO at unperturbed and inflamed mucous surfaces. Among the disorders, special attention is directed to cystic fibrosis and allergic reactions.
在我们的机体中，黏膜表面是抵御外界环境的重要屏障，这些表面有特定的代谢物通量以及防御反应的特定规则。主要的黏膜表面由呼吸系统和消化道的上皮形成。血红素过氧化物酶，如乳过氧化物酶（LPO）、髓过氧化物酶（MPO）和嗜酸性粒细胞过氧化物酶（EPO），在上皮表面和分泌物中发挥免疫保护作用。LPO由上皮细胞分泌，将表面衬里中的微生物维持在低水平，而MPO和EPO分别从募集到的中性粒细胞和嗜酸性粒细胞中释放到炎症黏膜表面。活化的血红素过氧化物酶能够将（拟）卤化物氧化为次卤酸和次硫氰酸盐。这些产物参与抵御病原体，但在病理条件下也可能导致细胞和组织损伤。本综述重点介绍了LPO、MPO和EPO在未受干扰和炎症黏膜表面的有益和有害功能。在这些疾病中，特别关注囊性纤维化和过敏反应。
