Formation and characterization of lipid droplets of the bovine corpus luteum

Authors

Heather A. Talbott, University of Nebraska Medical Center, Omaha & Oregon Health Sciences University/Oregon National Primate Research Center
Michele R. Plewes, University of Nebraska Medical Center, Omaha & 3Veterans Affairs Nebraska-Western Iowa Health Care System
Crystal Krause, University of Nebraska Medical Center, Omaha
Xiaoying Hou, University of Nebraska Medical Center, Omaha
Pan Zhang, University of Nebraska Medical Center, Omaha
William B. Rizzo, University of Nebraska Medical Center, Omaha
Jennifer R. Wood, University of Nebraska - LincolnFollow
Andrea S. Cupp, University of Nebraska at LincolnFollow
John S. Davis, University of Nebraska Medical Center, Omaha & 3Veterans Affairs Nebraska-Western Iowa Health Care SystemFollow

Document Type

Article

Date of this Version

2020

Citation

The Author(s) 2020

Comments

(2020) 10:11287 | https://doi.org/10.1038/s41598-020-68091-2

Abstract

Establishment and maintenance of pregnancy depends on progesterone synthesized by luteal tissue in the ovary. Our objective was to identify the characteristics of lipid droplets (LDs) in ovarian steroidogenic cells. We hypothesized that LDs are a major feature of steroidogenic luteal cells and store cholesteryl esters. Whole bovine tissues, isolated ovarian steroidogenic cells (granulosa, theca, small luteal, and large luteal), and isolated luteal LDs were assessed for LD content, LD-associated proteins and lipid analyses. Bovine luteal tissue contained abundant lipid droplets, LD-associated perilipins 2/3/5, hormone-sensitive lipase, and 1-acylglycerol-3-phosphate O-acyltransferase ABHD5. Luteal tissue was enriched in triglycerides (TGs) compared to other tissues, except for adipose tissue. Luteal cells were distinguishable from follicular cells by the presence of LDs, LD-associated proteins, and increased TGs. Furthermore, LDs from large luteal cells were numerous and small; whereas, LDs from small luteal cells were large and less numerous. Isolated LDs contained nearly all of the TGs and cholesteryl esters present in luteal tissue. Isolated luteal LDs were composed primarily of TG, with lesser amounts of cholesteryl esters, diglyceride and other phospholipids. Bovine luteal LDs are distinct from LDs in other bovine tissues, including follicular steroidogenic cells.