血红素氧合酶系统与早期自然流产的研究进展

Progress in research on relationship between heme oxygenases and early spontaneous abortion

血红素氧合酶是近年来发现的一种抗氧化酶,广泛存在于人体多种器官和组织中。血红素氧合酶催化血红素降解为同摩尔的一氧化碳、胆绿素和铁,胆绿素在胆绿素还原酶作用下,迅速生成胆红素。一氧化碳可以诱导血管扩张,胆红素是内源性的抗氧化剂。血红素氧合酶在人类胎盘和蜕膜组织中的表达与妊娠维持有关,其在母胎界面的表达下降可能是早期自然流产发生的机制之一。

Heme oxygenases（H0s） are a group of newly found antioxidants which exist broadly in many human organs and tissues. They are rate-limiting enzymes that degrade heme into same moles of dehydrobilirubin（ biliverdin）, CO and Fe, Under catabolism of biliverdin reductase, biliverdin is rapidly changed into bilirubin, avoiding toxic accumulation of free heme. Bilirubin is an endogeneous antioxidant, whereas CO induces vasodilatation. Expression of H0s in human placenta and decidual tissues is probably associated with pregnancy maintenance. Down-regulation of H0s expression in feto-maternal interface may be one of mechanisms of early spontaneous abortion.