Department of Molecular Prevention, Institute of Human Nutrition and Food Science, Christian-Albrechts-University of Kiel, Germany.
Physiol Genomics. 2013 Jul 2;45(13):539-51. doi: 10.1152/physiolgenomics.00007.2013. Epub 2013 May 28.
The metabolic and health-promoting effects of dietary restriction (DR) have been extensively studied in several species. The response to DR with respect to sex is essentially unknown. To address this question, we used the model organism Caenorhabditis elegans to analyze body composition and gene expression in males and hermaphrodites in response to DR. Unexpectedly, DR increased the fat-to-fat-free mass ratio and enlarged lipid droplets in both sexes to a similar extent. These effects were linked to a downregulation of the lipase-like 5 (lipl-5) gene in both sexes at two developmental stages. By contrast, the reductions in body size, protein content, and total RNA content in response to DR were more pronounced in hermaphrodites than in males. Functional enrichment analysis of gene expression data showed a DR-induced downregulation of several embryogenesis-associated genes concomitant with an ongoing expression of sperm-associated genes in hermaphrodites. In conclusion, DR increases fat stores in both sexes of C. elegans in the form of large and possibly lipolysis-resistant lipid droplets and markedly alters the reproductive program in hermaphrodites but not in males.
饮食限制（DR）对代谢和健康的促进作用在多种物种中得到了广泛研究。然而，关于性别对 DR 的反应，基本上还不清楚。为了解决这个问题，我们使用模式生物秀丽隐杆线虫来分析雄性和雌雄同体在 DR 下的体成分和基因表达。出乎意料的是，DR 使两性的体脂与去脂体重比增加，脂滴大小也显著增大。这些影响与两性在两个发育阶段中脂肪酶样 5（lipl-5）基因的下调有关。相比之下，DR 引起的体型、蛋白质含量和总 RNA 含量的减少在雌雄同体中比在雄性中更为明显。基因表达数据的功能富集分析显示，DR 诱导了几个与胚胎发生相关的基因下调，同时在雌雄同体中持续表达与精子相关的基因。总之，DR 以大的、可能是脂解抵抗的脂滴的形式增加了秀丽隐杆线虫雌雄两性的脂肪储存，并显著改变了雌雄同体的生殖程序，但对雄性没有影响。
