Oleic acid decouples fecundity and longevity via DAF-12 steroid hormone signaling in C. elegans

In animals, early-life starvation can program gene expression changes that result in profound effects on adult phenotypes. For C. elegans nematodes, passage through the stress-resistant dauer diapause stage due to early-life starvation establishes a cellular memory that manifests as increased metabolism and decreased fecundity compared to continuously developed adults. To further investigate the connection between metabolism and reproduction, we supplemented the diet of postdauer adults with different fatty acids and examined their life history traits. Here, we show that dietary oleic acid (OA) supplementation uniquely increases the fecundity of both postdauer and continuously developed adults in a DAF-12 steroid signaling dependent manner, potentially through the increased expression of fat-7 Δ9-desaturase and vit-2 vitellogen genes. In addition, OA may rescue increased ferroptosis in postdauer germ lines and has complex effects on adult lifespan depending on the animals’ life history. Together, our results suggest a model where OA modifies DAF-12 activity to positively regulate fecundity, metabolism, and lifespan in adults.