Kim Dong-Hwan, Lee Joonbum, Kim Sanggu, Lillehoj Hyun S, Lee Kichoon
Department of Animal Sciences, The Ohio State University, Columbus, OH, United States.
The Ohio State University Interdisciplinary Human Nutrition Program, The Ohio State University, Columbus, OH, United States.
Front Physiol. 2021 May 21;12:681562. doi: 10.3389/fphys.2021.681562. eCollection 2021.
Excessive adipose accretion causes health issues in humans and decreases feed efficiency in poultry. Although vitamin A has been known to be involved in adipogenesis, effects of all- retinoic acid (atRA), as a metabolite of vitamin A, on embryonic adipose development have not been studied yet. Avian embryos are developing in confined egg environments, which can be directly modified to study effects of nutrients on embryonic adipogenesis. With the use of quail embryos, different concentrations of atRA (0 M to 10 μM) were injected at embryonic day (E) 9, and adipose tissues were sampled at E14. Percentages of fat pad weights in embryo weights were significantly increased in the group injected with 300 nM of atRA. Also, among three injection time points, E5, E7, or E9, E7 showed the most significant increase in weight and percentage of inguinal fat at E14. Injection of atRA at E7 increased fat cell size in E14 embryos with up-regulation of pro-adipogenic marker genes ( and ) and down-regulation of a preadipocyte marker gene () in adipose tissues. These data demonstrate that atRA promotes hypertrophic fat accretion in quail embryos, implying important roles of atRA in embryonic development of adipose tissues.
过多的脂肪堆积会给人类带来健康问题，并降低家禽的饲料效率。尽管已知维生素A参与脂肪生成，但作为维生素A的一种代谢产物，全反式维甲酸（atRA）对胚胎脂肪发育的影响尚未得到研究。禽类胚胎在有限的蛋环境中发育，这种环境可以直接进行改变，以研究营养物质对胚胎脂肪生成的影响。利用鹌鹑胚胎，在胚胎第9天（E9）注射不同浓度的atRA（0 M至10 μM），并在E14采集脂肪组织。在注射300 nM atRA的组中，胚胎体重中脂肪垫重量的百分比显著增加。此外，在三个注射时间点（E5、E7或E9）中，E7显示在E14时腹股沟脂肪的重量和百分比增加最为显著。在E7注射atRA会增加E14胚胎的脂肪细胞大小，同时脂肪组织中促脂肪生成标记基因（和）上调，前脂肪细胞标记基因（）下调。这些数据表明，atRA促进鹌鹑胚胎的肥大性脂肪堆积，这意味着atRA在脂肪组织胚胎发育中具有重要作用。
