Estrogen protects against radiation-induced cataractogenesis.
Estrogen protects against radiation-induced cataractogenesis.
复制标题
DOI：
10.1667/rr1416.1
复制
发表时间：
2008-12
影响因子：
3.4
通讯作者：
Bigsby RM
中科院分区：
文献类型：
--
作者：
Dynlacht JR;Valluri S;Lopez J;Greer F;Desrosiers C;Caperell-Grant A;Mendonca MS;Bigsby RM
白内障的发生是放射治疗的并发症，当眼睛被包括在治疗领域。低剂量的密集电离空间辐射也可能导致宇航员患白内障的风险增加。我们之前报道过，与去卵巢的对照组相比，在γ照射眼前1周开始给卵巢切除的大鼠注射雌激素（17-β-雌二醇），导致白内障形成的发生率和发生率显著增加，潜伏期缩短。因此，我们得出结论，雌激素加速了辐射诱导的混浊的进展。我们现在表明，雌激素，如果持续使用，但在照射后开始，可以防止放射性白内障的发生。与去卵巢大鼠相比，放疗后接受雌激素治疗的去卵巢大鼠白内障的进展率和发病率都大大降低。在我们之前的研究中，在卵巢切除术和整个观察期间，在照射前1周给予雌二醇可提高白内障进展率。在放疗前仅给予1周雌激素对进展率没有影响，但导致发生率略有降低。我们得出的结论是，雌激素可能增强或防止放射性白内障的发生，这取决于它相对于照射时间的施用时间，并可能不同地调节白内障发生的开始和进展阶段。这些数据对宇航员和放疗患者具有重要意义。
Cataractogenesis is a complication of radiotherapy when the eye is included in the treatment field. Low doses of densely ionizing space radiation may also result in an increased risk of cataracts in astronauts. We previously reported that estrogen (17-β-estradiol), when administered to ovariectomized rats commencing 1 week before γ irradiation of the eye and continuously thereafter, results in a significant increase in the rate and incidence of cataract formation and a decreased latent period compared to an ovariectomized control group. We therefore concluded that estrogen accelerates progression of radiation-induced opacification. We now show that estrogen, if administered continuously, but commencing after irradiation, protects against radiation cataractogenesis. Both the rate of progression and incidence of cataracts were greatly reduced in ovariectomized rats that received estrogen treatment after irradiation compared to ovariectomized rats. As in our previous study, estradiol administered 1 week prior to irradiation at the time of ovariectomy and throughout the period of observation produced an enhanced rate of cataract progression. Estrogen administered for only 1 week prior to irradiation had no effect on the rate of progression but resulted in a slight reduction in the incidence. We conclude that estrogen may enhance or protect against radiation cataractogenesis, depending on when it is administered relative to the time of irradiation, and may differentially modulate the initiation and progression phases of cataractogenesis. These data have important implications for astronauts and radiotherapy patients.