Moderate and high intensity sprint exercise induce differential responses in COX4I2 and PDK4 gene expression in Thoroughbred horse skeletal muscle.
Abstract: The role of molecular signalling pathways in the phenotypic adaptation of skeletal muscle to different exercise stimuli in the Thoroughbred horse has not been reported previously. Objective: To examine CKM, COX4I1, COX4I2 and PDK4 gene expression following high intensity sprint and moderate intensity treadmill exercise stimuli in skeletal muscle of Thoroughbred horses. Methods: Two groups of trained 3-year-old Thoroughbred horses participated. Group A (n = 6 females, n = 3 males) participated in an incremental step test (moderate intensity) to fatigue or HR(max) on a Sato high speed treadmill (distance = 5418.67 m ± 343.21). Group B (n = 8 females) participated in routine 'work' (sprint) on an all-weather gallop (distance = 812.83 m ± 12.53). Biopsy samples were obtained from the gluteus medius pre-exercise (T(0)), immediately post exercise (T(1)) and 4 h post exercise (T(2)). For physiological relevance venous blood samples were collected to measure plasma lactate and creatine kinase concentrations. Changes in mRNA expression were determined by quantitative real-time RT-PCR for creatine kinase muscle (CKM), cytochrome c oxidase subunit IV isoform 1 (COX4I1), cytochrome c oxidase subunit IV isoform 2 (COX4I2) and pyruvate dehydrogenase kinase, isozyme 4 (PDK4) genes. Statistical significance (α < 0.05) was determined using Student's t tests. Results: COX4I2 mRNA expression decreased significantly in Group A and remained unchanged in Group B between T(0) vs. T(2) (-1.7-fold, P = 0.017; -1.0-fold, P = 0.859). PDK4 mRNA expression increased significantly in Group B but not in Group A between T(0) vs. T(1) (3.8-fold, P = 0.039; 1.4-fold, P = 0.591). There were no significant changes in the expression in CKM or COX4I1 mRNA abundance in either group. Conclusions: Different exercise protocols elicit variable transcriptional responses in key exercise relevant genes in equine skeletal muscle due to variation in metabolic demand.
© 2010 EVJ Ltd.
Publication Date: 2011-05-27 PubMed ID: 21059063DOI: 10.1111/j.2042-3306.2010.00206.xGoogle 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 examines the impact of different exercise intensities on gene expression in the skeletal muscle of Thoroughbred horses. The study finds that high-intensity sprint and moderate-intensity exercises induce varying responses in COX4I2 and PDK4 genes.
Objective
The main aim of the research was to investigate how CKM, COX4I1, COX4I2, and PDK4 genes react to two types of exercises in horse’s skeletal muscles. These exercises included high-intensity sprints and medium intensity treadmill workouts.
Methodology
- Two groups of trained 3-year-old Thoroughbred horses were part of this study. The first group consisted of both male and female horses that performed a moderate intensity incremental step test on a high-speed treadmill till they reached fatigue or maximum heart rate. The second group, consisting only females, was enrolled in a typical ‘work’ (sprint) on an all-weather gallop.
- The researchers collected biopsy samples from the gluteus medius before exercise (T(0)), immediately after exercise (T(1)), and four hours post-exercise (T(2)).
- Blood samples were also collected to measure plasma lactate and creatine kinase concentrations.
- To track changes in gene expression, quantitative real-time RT-PCR was used, specifically focusing on creatine kinase muscle (CKM), COX4I1, COX4I2, and PDK4 genes.
Results
- The expression of COX4I2 mRNA decreased significantly in the group engaged in moderate exercise and displayed no change in the high-intensity exercise group.
- On the other hand, PDK4 mRNA expression increased significantly in the high-intensity exercise group but not in the moderate exercise group.
- There were no significant changes in CKM or COX4I1 mRNA expression in either of the groups.
Conclusions
The findings suggest that different types of exercise affect the transcription of key exercise-related genes in the skeletal muscle of horses differently, due to varying metabolic demands. The study thus offers new insights into the biological mechanisms involved in horse training and performance enhancement.
Cite This Article
APA
Hill EW, Eivers SS, McGivney BA, Fonseca RG, Gu J, Smith NA, Browne JA, MacHugh DE, Katz LM.
(2011).
Moderate and high intensity sprint exercise induce differential responses in COX4I2 and PDK4 gene expression in Thoroughbred horse skeletal muscle.
Equine Vet J Suppl(38), 576-581.
https://doi.org/10.1111/j.2042-3306.2010.00206.x Publication
Researcher Affiliations
- Animal Genomics Laboratory, UCD School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Dublin 4, Ireland. Emmeline.Hill@ucd.ie
MeSH Terms
- Animals
- Electron Transport Complex IV / genetics
- Electron Transport Complex IV / metabolism
- Exercise Test
- Female
- Gene Expression Regulation / physiology
- Horses / genetics
- Horses / physiology
- Male
- Muscle, Skeletal / metabolism
- Physical Conditioning, Animal / physiology
- Protein Kinases / genetics
- Protein Kinases / metabolism
- RNA, Messenger / genetics
- RNA, Messenger / metabolism
Citations
This article has been cited 8 times.- Ebisuda Y, Mukai K, Takahashi Y, Yoshida T, Kawano A, Matsuhashi T, Miyata H, Kuwahara M, Ohmura H. Acute exercise in a hot environment increases heat shock protein 70 and peroxisome proliferator-activated receptor γ coactivator 1α mRNA in Thoroughbred horse skeletal muscle. Front Vet Sci 2023;10:1230212.
- Dzięgielewska A, Dunislawska A. Mitochondrial Dysfunctions and Potential Molecular Markers in Sport Horses. Int J Mol Sci 2022 Aug 4;23(15).
- Han H, McGivney BA, Farries G, Katz LM, MacHugh DE, Randhawa IAS, Hill EW. Selection in Australian Thoroughbred horses acts on a locus associated with early two-year old speed. PLoS One 2020;15(2):e0227212.
- Bryan K, McGivney BA, Farries G, McGettigan PA, McGivney CL, Gough KF, MacHugh DE, Katz LM, Hill EW. Equine skeletal muscle adaptations to exercise and training: evidence of differential regulation of autophagosomal and mitochondrial components. BMC Genomics 2017 Aug 9;18(1):595.
- Shin DH, Lee JW, Park JE, Choi IY, Oh HS, Kim HJ, Kim H. Multiple Genes Related to Muscle Identified through a Joint Analysis of a Two-stage Genome-wide Association Study for Racing Performance of 1,156 Thoroughbreds. Asian-Australas J Anim Sci 2015 Jun;28(6):771-81.
- Kocha KM, Reilly K, Porplycia DS, McDonald J, Snider T, Moyes CD. Evolution of the oxygen sensitivity of cytochrome c oxidase subunit 4. Am J Physiol Regul Integr Comp Physiol 2015 Feb 15;308(4):R305-20.
- Austin MMP, Ivey JLZ, Shepherd EA, Myer PR. Methodologies to Identify Metabolic Pathway Differences Between Emaciated and Moderately Conditioned Horses: A Review of Multiple Gene Expression Techniques. Animals (Basel) 2025 Oct 10;15(20).
- Barshick MR, Ely KM, Mogge KC, Chance LM, Johnson SE. Methylsulfonylmethane (MSM) Supplementation in Adult Horses Supports Improved Skeletal Muscle Inflammatory Gene Expression Following Exercise. Animals (Basel) 2025 Jan 14;15(2).
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
