紐約(路透社健康版)12月19日——卡羅琳斯卡大學(xué)的研究者在11月號(hào)的《生育與不育》上撰文指出,，細(xì)胞色素P450酶多態(tài)性攜帶者妊娠早期流產(chǎn)的風(fēng)險(xiǎn)要大一些。
細(xì)胞色素P450 1B1 (CYP1B1)參與雄性激素和雌性激素以及茶堿,、咖啡因還有其它外源化合物與前致癌劑的代謝,。CYP1B1在子宮,、卵巢和乳房中表達(dá)。
斯德哥爾摩的Anna-Helena Karypidis博士和同事們進(jìn)行了一項(xiàng)人群調(diào)查,，包括507名妊娠早期流產(chǎn)的婦女和908名妊娠早期正常的對(duì)照者,。所有的婦女都是CYP1B1基因多態(tài)型。母親的年齡,、吸煙狀況,、咖啡和酒精的攝入、胎兒的染色體組型和惡心以及嘔吐都被納入評(píng)估,。
Karypidis博士的團(tuán)隊(duì)發(fā)現(xiàn)CYP1B1變體攜帶者中流產(chǎn)的概率比是1.46,。在妊娠頭三個(gè)月，CYP1B1多態(tài)性同型結(jié)合攜帶者中,，咖啡飲用者比不飲用者流產(chǎn)的風(fēng)險(xiǎn)略高,。咖啡因增加的風(fēng)險(xiǎn)似乎在吸煙者中無(wú)效,。
Karypidis博士告訴路透社健康版,，咖啡消費(fèi)與流產(chǎn)之間的關(guān)系“可能增加了對(duì)自然流產(chǎn)病因?qū)W的理解”。
“然而,，在介入研究完成之前,，基于CYP1B1基因篩選的飲食限制建議是不成熟的，”她警告說(shuō),。“如果未來(lái)的介入試驗(yàn)證實(shí)在那些攜有危險(xiǎn)基因型的人群中限制咖啡因能夠降低自然流產(chǎn)的比率,，那么那時(shí)候進(jìn)行基因篩選和飲食控制可能是恰當(dāng)?shù)摹?rdquo;
“CYP1B1酶在子宮中表達(dá),，代謝性激素和外源性物質(zhì)，包括咖啡因,，”她解釋說(shuō),。“咖啡因是世界上應(yīng)用最廣泛的外源性化合物之一，并且早年被認(rèn)為與大量咖啡飲用者中增加的妊娠早期自然流產(chǎn)風(fēng)險(xiǎn)有關(guān),。”
研究者補(bǔ)充說(shuō),，這種變體“確實(shí)普遍，因而它在能導(dǎo)致妊娠早期流產(chǎn)的機(jī)制中發(fā)揮的作用可能有重大臨床意義,。”
英文原文：
Cytochrome P450 Variant Associated With First Trimester Miscarriage
NEW YORK (Reuters Health) Dec 19 - Carriers of a polymorphism of the cytochrome P450 enzyme are at higher risk of miscarriage in the first trimester of pregnancy, Karolinska University investigators report in the November issue of Fertility and Sterility.
The variant of cytochrome P450 1B1 (CYP1B1) is involved in the metabolism of androgens and estrogen, as well as theophylline, caffeine and other xenobiotics and some procarcinogens. CYP1B1 is expressed in the uterus, ovaries and breast.
Dr. Anna-Helena Karypidis, and colleagues in Stockholm, conducted a population-based study of 507 women with first trimester miscarriages and 908 controls with normal first trimester pregnancies. All of the women were genotyped for the CYP1B1 polymorphism. Maternal age, smoking status, coffee and alcohol intake, fetal karyotype and nausea and vomiting were also assessed.
Dr. Karypidis's team found an odds ratio of 1.46 for miscarriage among carriers of the CYP1B1 variant. Coffee drinkers who were homozygous carriers of the CYP1B1 polymorphism had a slightly higher risk than carriers who did not drink coffee during the first trimester. The increased risk with caffeine appeared to be nullified among smokers.
The link between coffee consumption and miscarriage "might add to the understanding of the etiology of spontaneous abortions," Dr. Karypidis told Reuters Health.
"However, before intervention studies are done, recommendations of diet restrictions based on genetic screening of CYP1B1 are premature," she cautioned. "If future intervention trials prove that caffeine restriction in those carrying the risk genotype will reduce their rate of spontaneous abortions, screening and diet guidance might be appropriate" at that time.
"The enzyme CYP1B1 is present in the uterus and metabolizes both sex hormones and xenobiotics, including caffeine," she explained. "Caffeine is one of the most widely used xenobiotic compounds in the world and has earlier been linked to an increased risk of first trimester spontaneous abortion among heavy coffee drinkers."
The investigators add that the variant "is rather common, and therefore its role in the mechanisms that lead to first trimester miscarriage may be clinically significant."
