Follicular metabolic alterations are associated with obesity in mares and can be mitigated by dietary supplementation.
Abstract: Obesity is a growing concern in human and equine populations, predisposing to metabolic pathologies and reproductive disturbances. Cellular lipid accumulation and mitochondrial dysfunction play an important role in the pathologic consequences of obesity, which may be mitigated by dietary interventions targeting these processes. We hypothesized that obesity in the mare promotes follicular lipid accumulation and altered mitochondrial function of oocytes and granulosa cells, potentially contributing to impaired fertility in this population. We also predicted that these effects could be mitigated by dietary supplementation with a combination of targeted nutrients to improve follicular cell metabolism. Twenty mares were grouped as: Normal Weight [NW, n = 6, body condition score (BCS) 5.7 ± 0.3], Obese (OB, n = 7, BCS 7.7 ± 0.2), and Obese Diet Supplemented (OBD, n = 7, BCS 7.7 ± 0.2), and fed specific feed regimens for ≥ 6 weeks before sampling. Granulosa cells, follicular fluid, and cumulus-oocyte complexes were collected from follicles ≥ 35 mm during estrus and after induction of maturation. Obesity promoted several mitochondrial metabolic disturbances in granulosa cells, reduced L-carnitine availability in the follicle, promoted lipid accumulation in cumulus cells and oocytes, and increased basal oocyte metabolism. Diet supplementation of a complex nutrient mixture mitigated most of the metabolic changes in the follicles of obese mares, resulting in parameters similar to NW mares. In conclusion, obesity disturbs the equine ovarian follicle by promoting lipid accumulation and altering mitochondrial function. These effects may be partially mitigated with targeted nutritional intervention, thereby potentially improving fertility outcomes in the obese female.
© 2024. The Author(s).
Publication Date: 2024-03-30 PubMed ID: 38555310PubMed Central: PMC10981747DOI: 10.1038/s41598-024-58323-0Google 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
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The study explores the negative effects of obesity on the reproductive capabilities of mares and finds that these effects can be mitigated through nutritional intervention. The researchers discovered that obesity can cause disruptions in mitochondrial metabolic activity in these mares, while a diet supplement restores these parameters to similar levels of non-obese horses, potentially improving fertility.
Objective of the Research
- The research aimed to understand how obesity affects follicular metabolic alterations in mares and if the condition could be reversed with targeted nutritional interventions.
Hypothesis and Predictions
- The researchers hypothesized that obesity might boost follicular lipid accumulation and disrupt mitochondrial activity in granulosa cells and oocytes, leading to fertility issues in mares.
- They further proposed that these effects could be reversed by supplementing the mare’s diet with a mix of specific nutrients aimed at improving the metabolism of follicular cells.
Research Method
- Twenty mares were separated into groups of Normal Weight (NW), Obese (OB), and Obese Diet Supplemented (OBD), and were fed specific diets for over six weeks before sampling.
- Granulosa cells, follicular fluid, and cumulus-oocyte complexes were collected from follicles that were 35 mm or larger during estrus and after the induction of maturation.
Findings
- Obesity caused several mitochondrial metabolic disturbances in granulosa cells, led to decreased L-carnitine availability in the follicle, increased lipid accumulation in cumulus cells and oocytes, and elevated oocyte metabolism.
- The diet supplement, a complex nutrient mixture, could mitigate most metabolic changes in the follicles of obese mares, resulting in parameters nearly equivalent to those of NW mares.
Conclusion
- The study concluded that obesity disrupts the equine ovarian follicle by promoting lipid accumulation and impairing mitochondrial function.
- The findings suggest that these negative effects can be mitigated, at least partly, through targeted nutritional intervention, potentially enhancing fertility outcomes in obese females.
Cite This Article
APA
Catandi GD, Fresa KJ, Cheng MH, Whitcomb LA, Broeckling CD, Chen TW, Chicco AJ, Carnevale EM.
(2024).
Follicular metabolic alterations are associated with obesity in mares and can be mitigated by dietary supplementation.
Sci Rep, 14(1), 7571.
https://doi.org/10.1038/s41598-024-58323-0 Publication
Researcher Affiliations
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Road, Fort Collins, CO, 80521, USA.
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
- Department of Veterinary Clinical Sciences, Oklahoma State University, Stillwater, OK, 74078, USA.
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Road, Fort Collins, CO, 80521, USA.
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, 80523, USA.
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
- Proteomics and Metabolomics Facility, Colorado State University, Fort Collins, CO, 80523, USA.
- Department of Electrical and Computer Engineering, Colorado State University, Fort Collins, CO, 80523, USA.
- School of Biomedical Engineering, Colorado State University, Fort Collins, CO, 80523, USA.
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA.
- Equine Reproduction Laboratory, Department of Biomedical Sciences, Colorado State University, 3101 Rampart Road, Fort Collins, CO, 80521, USA. elaine.carnevale@colostate.edu.
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA. elaine.carnevale@colostate.edu.
MeSH Terms
- Humans
- Horses
- Animals
- Female
- Ovarian Follicle / metabolism
- Oocytes / metabolism
- Follicular Fluid
- Obesity / metabolism
- Lipids
- Dietary Supplements
Grant Funding
- Grant No. COLV 2021-09 / Project Accession No. 1026913 / USDA National Institute of Food and Agriculture Animal Health and Disease
Conflict of Interest Statement
The authors declare no competing interests.
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