1. Heat-induced hyperthermia impacts the follicular fluid proteome of the periovulatory follicle in lactating dairy cows.
- Author
-
Rispoli LA, Edwards JL, Pohler KG, Russell S, Somiari RI, Payton RR, and Schrick FN
- Subjects
- Animal Husbandry, Animals, Bradykinin analysis, Bradykinin metabolism, Cattle, Cumulus Cells drug effects, Female, Gonadotropin-Releasing Hormone administration & dosage, Heat Stress Disorders etiology, Hot Temperature adverse effects, Lactation physiology, Ovulation drug effects, Proteome metabolism, Proteomics, Tennessee, Transferrin analysis, Transferrin metabolism, Cumulus Cells metabolism, Follicular Fluid metabolism, Heat Stress Disorders physiopathology, Ovulation physiology, Proteome analysis
- Abstract
We hypothesized that heat-induced perturbations in cumulus cells surrounding the maturing oocyte may extend to the mural granulosa of the periovulatory follicle in the heat-stressed cow to subsequently the follicular fluid proteome. Lactating Holsteins were pharmacologically stimulated to have a dominant follicle that was capable of responding to a gonadotropin releasing hormone-induced luteinizing hormone surge. Following gonadotropin releasing hormone administration, cows were maintained at ~67 temperature humidity index (THI; thermoneutral conditions) or exposed to conditions simulating an acute heat stress event (71 to 86 THI; heat stress for ~12 h). Dominant follicle collection was conducted in the periovulatory period ~16 h after gonadotropin releasing hormone. Follicular fluid proteome from thermoneutral (n = 5) and hyperthermic (n = 5) cows was evaluated by quantitative tandem mass spectrometry (nano LC-MS/MS). We identified 35 differentially-abundant proteins. Functional annotation revealed numerous immune-related proteins. Subsequent efforts revealed an increase in levels of the proinflammatory mediator bradykinin in follicular fluid (P = 0.0456) but not in serum (P = 0.9319) of hyperthermic cows. Intrafollicular increases in transferrin (negative acute phase protein) in hyperthermic cows (P = 0.0181) coincided with a tendency for levels to be increased in the circulation (P = 0.0683). Nine out of 15 cytokines evaluated were detected in follicular fluid. Heat stress increased intrafollicular interleukin 6 levels (P = 0.0160). Whether hyperthermia-induced changes in the heat-stressed cow's follicular fluid milieu reflect changes in mural granulosa, cumulus, other cell types secretions, and/or transudative changes from circulation remains unclear. Regardless of origin, heat stress/hyperthermia related changes in the follicular fluid milieu may have an impact on components important for ovulation and competence of the cumulus-oocyte complex contained within the periovulatory follicle., Competing Interests: Authors JLE/LAR/KGP/RRP/FNS have no competing interests. Authors SR/RIS are affiliated/employed by ITSI Biosciences. Their commercial affiliation does not alter our adherence to PLOS ONE policies on sharing data and materials.
- Published
- 2019
- Full Text
- View/download PDF