Irisin decreases follicle development in cattle and inhibits theca cell steroidogenesis through focal adhesion kinase signaling
Bibliographic record
Abstract
In brief: Irisin is a muscle and adipose-derived hormone that is secreted in response to negative energy balance in cattle. We show here that irisin reduced follicle growth and theca cell function. Abstract: At the onset of lactation, dairy cattle are anestrous owing mainly to a state of negative energy balance. Adipose tissue is mobilized to meet the energy demands of milk production, and this alters the secretion of adipose-derived hormones, called adipokines. Irisin is a myokine/adipokine that may play a role in fertility; plasma concentrations increase in cattle postpartum, and irisin decreased progesterone and estradiol secretion from bovine granulosa cells in vitro. To our knowledge, the effects of irisin on bovine theca cell function in vitro and on follicle growth in vivo have not been reported. We hypothesized that irisin negatively affects theca cell function in vitro and causes follicle regression in vivo using well-established bovine models. Under physiological concentrations of insulin (0.2 ng/mL), irisin did not affect glucose uptake, but decreased testosterone secretion and stimulated PTK2 and MTOR phosphorylation. Inhibiting PTK2 activity abolished the ability of irisin to decrease testosterone secretion. Injection of irisin directly into a growing follicle in vivo caused follicle regression. We conclude that irisin decreases bovine theca cell steroidogenesis through PTK2 signaling, and combined effects on theca and granulosa cells cause follicle regression.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".