Short photoperiod initiated during adulthood sustains reproductive function in older female siberian hamsters more effectively than short photoperiod initiated before puberty.
Short photoperiod initiated during adulthood sustains reproductive function in older female siberian hamsters more effectively than short photoperiod initiated before puberty.
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成年期开始的短光周期比青春期前开始的短光周期更有效地维持老年雌性西伯利亚仓鼠的生殖功能。
DOI：
10.1095/biolreprod.109.081968
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发表时间：
2010
影响因子：
3.6
通讯作者：
Cruickshank,Jenifer
中科院分区：
文献类型：
--
作者：
Place,NedJ;Cruickshank,Jenifer
雌性哺乳动物的生殖衰老的特征是生育力和繁殖力逐渐下降。许多女性推迟她们的第一次足月怀孕，直到她们的生殖潜力已经下降的年龄。目前还没有可用于延缓衰老过程的治疗方法。在数量有限的啮齿动物中，热量限制维持了老年雌性动物的生殖功能，在大多数研究中，性成熟被推迟，因为热量限制是在断奶时开始的。我们之前曾报道过在短光周期(SP)中饲养的西伯利亚雌性仓鼠的类似结果，这严重抑制了生殖生理。与长光周期(LP)饲养的仓鼠相比，SP饲养的雌性仓鼠成熟较晚，在9个月龄时繁殖成功。在此，我们确定了SP是否需要延迟开始的性成熟来减缓生殖衰老。我们在性成熟之前或之后启动了6个月的SP周期，并在12个月龄时测量了雌性动物的生殖成功。与青春期前施加SP相比，在青春期后开始在SP中维持仓鼠的产仔成功率(77%)显著高于在青春期前施加SP(35%)；在断奶成功率方面差异更大(分别为73%和12%)。无论使用哪种SP方案，暴露在SP环境中的雌性产仔成功率显著高于持续使用LP的12个月龄雌性(6%)。SP在减慢女性生殖衰老方面的效果在几个生命阶段都很明显，并且在青春期之后而不是青春期之前开始治疗时效果更好。
Reproductive aging in female mammals is characterized by a progressive decline in fertility and fecundity. Many women delay their first full-term pregnancy until an age at which their reproductive potential has already declined. No treatment is presently available to delay the aging process. In a limited number of rodent species, caloric restriction sustained reproductive function in older females, and in most investigations, sexual maturation was delayed because caloric restriction was initiated at weaning. We have previously reported similar outcomes in female Siberian hamsters that were reared in short photoperiod (SP), which profoundly inhibits reproductive physiology. When compared to hamsters held in long photoperiod (LP), females reared in SP matured much later and had greater reproductive success at 9 mo of age. Herein, we determined if delayed onset of sexual maturation was necessary for SP to decelerate reproductive aging. We initiated a 6-mo period of SP before or after sexual maturation and measured the reproductive success of females at 12 mo of age. Maintenance of hamsters in SP beginning after puberty was associated with significantly greater litter success (77%) compared to imposition of SP before puberty (35%); the difference in weaning success was even greater (73% and 12%, respectively). Regardless of which SP regime was used, litter success of females exposed to SP was substantially greater than that of 12-mo-old females held continuously in LP (6%). The efficacy of SP in decelerating female reproductive aging is manifest at several life stages and is greater when treatment is initiated after rather than before puberty.