Clark D L, Strasburg G M, Reed K M, Velleman S G
Department of Animal Sciences, The Ohio State University/Ohio Agricultural Research and Development Center, Wooster OH; 44691.
Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824.
Poult Sci. 2017 Apr 1;96(4):1015-1027. doi: 10.3382/ps/pew374.
Immature poults have an inefficient thermoregulatory system, and therefore extreme ambient temperatures can impact their internal body temperature. Satellite cells, the only posthatch myonuclei source, are multipotential stem cells and sensitive to temperature. Selection for faster-growing, high-yielding birds has altered satellite-cell properties. The objective of the current study was to determine how temperature affects adipogenic properties of satellite cells isolated from the pectoralis major ( ) muscle of Randombred Control line ( ) and F line turkeys selected only for increased 16-wk body weight from the RBC2 line. Satellite cells were cultured at 2°C incremental temperatures between 33 and 43°C and compared to cells cultured at the control temperature of 38°C to ascertain temperature effects on lipid accumulation and expression of adipogenic genes: CCAAT/enhancer-binding protein-β ( ), peroxisome proliferator-activated receptor-γ ( ), and stearoyl-CoA desaturase ( ). During proliferation, the amount of quantifiable lipid in both F and RBC2 satellite cells increased at temperatures above 38°C ( P < 0.01) and decreased at temperatures below 38°C ( P < 0.01). Above 38°C, RBC2 satellite cells had more lipid ( P = 0.02) compared to the F line, whereas there were few differences between lines below 38°C. At 72 h of proliferation, expression of C/EBPβ , PPARγ , and SCD decreased ( P ≤ 0.02) as temperatures increased from 33 to 43°C in both cell lines. During differentiation expression of C/EBPβ increased ( P < 0.01) as temperatures increased from 33 to 43°C in both cell lines. In F line satellite cells, PPARγ expression decreased ( P < 0.01) with increasing temperatures during differentiation, whereas there was no linear trend in RBC2 cells. During differentiation expression of SCD increased as temperatures increased ( P < 0.01) in RBC2 cells, and there was no linear trend within the F line. Results from the current study suggest that environmental temperature can affect p. major satellite cellular fate; however, selection for increased body weight had little impact on these cellular responses.
未成熟的雏禽具有低效的体温调节系统，因此极端的环境温度会影响它们的体内温度。卫星细胞是孵化后唯一的肌细胞核来源，是多能干细胞且对温度敏感。选择生长更快、产量更高的禽类改变了卫星细胞的特性。本研究的目的是确定温度如何影响从随机繁殖对照系（RBC2）和仅从RBC2系中选择16周龄体重增加的F系火鸡的胸大肌中分离出的卫星细胞的成脂特性。卫星细胞在33至43°C之间以2°C的增量温度进行培养，并与在38°C对照温度下培养的细胞进行比较，以确定温度对脂质积累和成脂基因表达的影响：CCAAT/增强子结合蛋白-β（C/EBPβ）、过氧化物酶体增殖物激活受体-γ（PPARγ）和硬脂酰辅酶A去饱和酶（SCD）。在增殖过程中，F系和RBC2系卫星细胞中可量化脂质的量在高于38°C的温度下增加（P<0.01），在低于38°C的温度下减少（P<0.01）。高于38°C时，与F系相比，RBC2系卫星细胞的脂质更多（P = 0.02），而在低于38°C时，品系间差异不大。在增殖72小时时，随着温度从33°C升高到43°C，两个细胞系中C/EBPβ、PPARγ和SCD的表达均下降（P≤0.02）。在分化过程中，随着温度从33°C升高到43°C，两个细胞系中C/EBPβ的表达均增加（P<0.01）。在F系卫星细胞中，分化过程中PPARγ的表达随温度升高而下降（P<0.01），而在RBC2细胞中没有线性趋势。在RBC2细胞中，分化过程中SCD的表达随温度升高而增加（P<0.01），而在F系中没有线性趋势。本研究结果表明，环境温度会影响胸大肌卫星细胞的命运；然而，选择增加体重对这些细胞反应的影响很小。
