A synergistic effect of insulin-like growth factor (IGF-I) on equine luteinizing hormone (eLH)-induced testosterone production from cultured Leydig cells of horses.
Abstract: Localization of IGF-I and IGF-IR were observed in Leydig cells of horses using immunohistochemistry (IHC), suggesting IGF-I may play a role in equine Leydig cell steroidogenesis. Previous studies in other species have indicated that IGF-I increases basal and/or LH/hCG-induced testosterone production. The objectives of this study were to (1) test the synergistic effect of IGF-I on eLH-induced testosterone production in cultured equine Leydig cells and (2) determine if this effect is reproductive stage-dependent. Testes were collected from five pubertal (1.1±0.1 year; 1-1.5 year) and eight post-pubertal (2.88±0.35 years; 2-4 years) stallions during routine castrations at the UC Davis Veterinary Hospital. Leydig cells were isolated using validated enzymatic and mechanical procedures. Leydig cells were treated without (control) or with increasing concentrations of purified pituitary-derived eLH and/or recombinant human IGF-I (rhIGF-I) and incubated under 95% air: 5% CO(2) at 32°C for 24h. After 24h, culture media was collected and frozen at -20°C until analyzed for testosterone by a validated radioimmunoassay (RIA). In pubertal stallions, treatment with both increasing concentrations of rhIGF-I and 5ng/ml of eLH failed to demonstrate a significant difference in testosterone production compared with 5ng/ml of eLH only. However, in post-pubertal stallions, a significant increase in the concentration of testosterone in culture media was observed from Leydig cells treated with various concentrations of rhIGF-I and 1 or 5ng/ml of eLH compared with 1 or 5ng/ml of eLH only. In conclusion, IGF-I has a synergistic effect on eLH-induced testosterone production in cultured equine Leydig cells from post-pubertal but not pubertal stallions.
Copyright © 2011. Published by Elsevier B.V.
Publication Date: 2011-05-24 PubMed ID: 21676562DOI: 10.1016/j.anireprosci.2011.05.008Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
The research investigates the combined effect of insulin-like growth factor (IGF-I) and a type of reproductive hormone (eLH) on testosterone production in horse Leydig cells, revealing IGF-I increases eLH-induced testosterone production in post-pubertal horses.
Objective of the Research
- The study aimed to examine the combined effect of IGF-I and eLH on the production of testosterone in Leydig cells of horses, which are essential cells in testes responsible for producing testosterone.
- Another goal was to determine whether this effect varies based on the reproductive stage – specifically comparing pubertal and post-pubertal horse cells.
Methodology
- The researchers collected testes from pubertal (1-1.5 years old) and post-pubertal stallions (2-4 years old) during routine castrations at the UC Davis Veterinary Hospital.
- They isolated the Leydig cells using enzymatic and mechanical procedures that have been already validated in previous researches.
- The Leydig cells were then treated with a purified pituitary-derived eLH and/or recombinant human IGF-I (rhIGF-I).
- Following incubation for 24 hours, the culture media wherein the cells were grown was assessed for testosterone via a radioimmunoassay (RIA), a technique that measures antibody-antigen reactions to quantify targeted molecules, in this case, testosterone.
Findings
- The results showed that combined treatment of rhIGF-I and eLH did not significantly affect testosterone levels in pubertal horse cells compared to treatment with eLH only.
- However, in post-pubertal stallion cells, a significant increase in testosterone production was observed with the combined treatment of rhIGF-I and eLH compared with eLH only.
Conclusion
- In conclusion, the results revealed that IGF-I intensifies the eLH-stimulated testosterone production in post-pubertal horse Leydig cells.
- However, this enhanced effect is not observed in Leydig cells from pubertal stallions, suggesting that the influence of IGF-I may depend on the reproductive stage.
Cite This Article
APA
Yoon MJ, Roser JF.
(2011).
A synergistic effect of insulin-like growth factor (IGF-I) on equine luteinizing hormone (eLH)-induced testosterone production from cultured Leydig cells of horses.
Anim Reprod Sci, 126(3-4), 195-199.
https://doi.org/10.1016/j.anireprosci.2011.05.008 Publication
Researcher Affiliations
- Department of Animal Science, University of California-Davis, 1 Shields Ave., Davis, CA 95616, USA.
MeSH Terms
- Animals
- Cells, Cultured
- Dose-Response Relationship, Drug
- Drug Synergism
- Horses / physiology
- Insulin-Like Growth Factor I / pharmacology
- Leydig Cells / drug effects
- Leydig Cells / metabolism
- Luteinizing Hormone / pharmacology
- Male
- Sexual Maturation / physiology
- Testosterone / metabolism
Citations
This article has been cited 3 times.- Yang Y, Suwimonteerabutr J, Angkawanish T, Chatdarong K. Serum Insulin-like Growth Factor-1 Is a Biomarker of Testosterone Production and Intact Acrosome in Asian Elephants (Elephas maximus).. Animals (Basel) 2022 Jun 17;12(12).
- Yoon M, Jiang J, Chung KH, Roser JF. Immunolocalization of insulin-like growth factor-I (IGF-I) and its receptors (IGF-IR) in the equine epididymis.. J Reprod Dev 2015;61(1):30-4.
- Jung H, Roser JF, Yoon M. UTF1, a putative marker for spermatogonial stem cells in stallions.. PLoS One 2014;9(10):e108825.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
