Harper Kathryn M, Tunc-Ozcan Elif, Graf Evan N, Herzing Laura B K, Redei Eva E
The Asher Center, Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, United States.
Lurie's Children Research Center, Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, United States.
Psychoneuroendocrinology. 2014 Jul;45:187-91. doi: 10.1016/j.psyneuen.2014.04.002. Epub 2014 Apr 13.
Insulin-like growth factor 2 (Igf2) regulates development, memory and adult neurogenesis in the hippocampus. Calorie restriction (CR) is known to modulate non-neuronal Igf2 expression intergenerationally, but its effect has not been evaluated on brain Igf2. Here, Sprague-Dawley (S) dams underwent moderate CR between gestational days 8-21. To identify parent of origin expression pattern of the imprinted Igf2 gene, their offspring (SS F1) were mated with naïve male or female Brown Norway (B) rats to obtain the second generation (BS and SB F2) progeny. CR did not affect adult hippocampal Igf2 transcript levels in SS F1 males or their BS F2 progeny, but increased it in SS F1 females and their SB F2 offspring. The preferentially maternal Igf2 expression in the SB F2 control male hippocampus relaxed to biallelic with CR, with no effect of grandmaternal diet in any other groups. Thus, allele-specific and total expression of hippocampal Igf2 is affected by maternal, grandmaternal CR in a strain and sex-specific manner.
胰岛素样生长因子2（Igf2）调节海马体的发育、记忆和成年神经发生。已知热量限制（CR）会代际调节非神经元Igf2的表达，但其对脑Igf2的影响尚未得到评估。在此，斯普拉格-道利（S）品系的母鼠在妊娠第8至21天期间进行适度热量限制。为了确定印记Igf2基因的亲本来源表达模式，将它们的后代（SS F1）与未处理的雄性或雌性挪威棕鼠（B）交配，以获得第二代（BS和SB F2）后代。热量限制并未影响SS F1雄性及其BS F2后代成年海马体中的Igf2转录水平，但在SS F1雌性及其SB F2后代中有所增加。在SB F2对照雄性海马体中，优先的母源Igf2表达在热量限制下转变为双等位基因表达，而在其他任何组中，祖母的饮食均无影响。因此，海马体Igf2的等位基因特异性表达和总表达受到母源、祖母源热量限制的影响，呈现品系和性别特异性。
