Maternal glucocorticoids promote offspring growth without inducing oxidative stress or shortening telomeres in wild red squirrels
Maternal glucocorticoids promote offspring growth without inducing oxidative stress or shortening telomeres in wild red squirrels
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DOI：
10.1242/jeb.212373
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发表时间：
2020-01-01
影响因子：
2.8
通讯作者：
Monaghan, Pat
中科院分区：
文献类型：
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作者：
Dantzer, Ben;van Kesteren, Freya;Monaghan, Pat
繁殖期雌性体内糖皮质激素（GC）水平升高可能会引起后代生活史的适应性改变。由糖皮质激素水平升高的母亲所生育的后代可能会更好地准备应对恶劣环境，在这种环境中，更快的生活节奏是有益的。我们研究了在怀孕或哺乳期的北美红松鼠（Tamiasciurus hudsonicus）中通过实验升高的糖皮质激素如何影响后代的产后生长、结构大小以及三种不同组织（血液、心脏和肝脏）中的氧化应激水平（两种抗氧化剂和氧化蛋白损伤）以及肝脏端粒长度。我们预测，接受糖皮质激素处理的母亲所生育的后代生长速度会更快，但也会有更高的氧化应激水平和更短的端粒，这可能预示着寿命缩短。怀孕期接受糖皮质激素处理的母亲所生育的后代在出生时体重轻8.3%，但（体重）生长速度比对照组快17.0%，而哺乳期接受糖皮质激素处理的母亲所生育的后代生长速度比对照组慢34.8%，且出生时体重没有差异。在怀孕期或哺乳期对母亲使用糖皮质激素并没有改变其后代的氧化应激水平或端粒长度。任何处理组中生长迅速的后代都没有更高的氧化应激水平或更短的端粒长度，这表明在生命早期生长较快的后代在这一生长阶段之后没有表现出氧化代价。我们的研究结果表明，母体糖皮质激素水平升高可能会诱导后代生长的可塑性，而不会给后代带来可能导致寿命缩短的长期氧化代价。
Elevations in glucocorticoid (GC) levels in breeding females may induce adaptive shifts in offspring life histories. Offspring produced by mothers with elevated GCs may be better prepared to face harsh environments, where a faster pace of life is beneficial. We examined how experimentally elevated GCs in pregnant or lactating North American red squirrels (Tamiasciurus hudsonicus) affected offspring postnatal growth, structural size and oxidative stress levels (two antioxidants and oxidative protein damage) in three different tissues (blood, heart and liver) and liver telomere lengths. We predicted that offspring from mothers treated with GCs would grow faster but would also have higher levels of oxidative stress and shorter telomeres, which may predict reduced longevity. Offspring from mothers treated with GCs during pregnancy were 8.3% lighter around birth but grew (in body mass) 17.0% faster than those from controls, whereas offspring from mothers treated with GCs during lactation grew 34.8% slower than those from controls and did not differ in body mass around birth. Treating mothers with GCs during pregnancy or lactation did not alter the oxidative stress levels or telomere lengths of their offspring. Fast-growing offspring from any of the treatment groups did not have higher oxidative stress levels or shorter telomere lengths, indicating that offspring that grew faster early in life did not exhibit oxidative costs after this period of growth. Our results indicate that elevations in maternal GCs may induce plasticity in offspring growth without long-term oxidative costs to the offspring that might result in a shortened lifespan.