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Research in veterinary science2018; 118; 184-190; doi: 10.1016/j.rvsc.2018.02.012

Changes in plasma 5-HT levels and equine leukocyte SERT expression in response to treadmill exercise.

Abstract: Serotonin (5-HT) is a neurohormone transported from plasma into platelets and leukocytes by a specific transporter (SERT). While it is known that the brain 5-HT system is modulated by physical exercise, the peripheral serotoninergic response to exercise is not yet fully elucidated. In particular, this study aimed to evaluate changes in plasma 5-HT levels and equine leukocyte SERT expression in response to treadmill exercise in untrained horses. Analyses were carried out pre- and post-treadmill exercise. 5-HT plasma levels were analysed by HPLC. Leukocytes and platelets were isolated to perform Real Time PCR for the evaluation of SERT mRNA levels. Western blot was conducted for the detection of SERT protein levels. The presence of SERT in leukocytes was analysed by flow cytometry. The functionality of SERT on leukocytes was investigated by using paroxetine as inhibitor of 5-HT reuptake. Results showed a significant decrease in SERT levels after exercise in both leukocytes and platelets and a significant increase in plasma 5-HT levels. Flow cytometry revealed that SERT is functional in one specific horse leukocyte subpopulation, still not identified, and paroxetine was able to block 5-HT reuptake into leukocytes. The exercise may have induced an increased mobilization of free-tryptophan and a release of 5-HT from the stores in the blood. High concentrations of plasma 5-HT could have caused a reduction in SERT expression affecting cellular 5-HT storage/uptake. The increase of cortisol levels after treadmill exercise was not significant. Exercise modulates the peripheral serotonin metabolism. More research is needed to assess its physiological implications.
Publication Date: 2018-02-27 PubMed ID: 29518708DOI: 10.1016/j.rvsc.2018.02.012Google Scholar: Lookup
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  • 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.

This research studied how physical exercise affects serotonin (a neurohormone) levels and the related transporter protein SERT in horses. Experimental results indicate that physical exercise might reduce SERT levels in leukocytes and platelets while increase serotonin levels in plasma.

Research Objective and Methodology

  • The study aimed to investigate how treadmill exercise changes the levels of serotonin (5-HT) in plasma and how it affects the expression of the Serotonin Transporter (SERT) in equine leukocytes in untrained horses.
  • Research involved performing analyses before and after the horses performed treadmill exercises.
  • Plasma levels of serotonin were analyzed using High-Performance Liquid Chromatography (HPLC).
  • Leukocytes and platelets were isolated in order to perform Real Time Polymerase Chain Reaction (RT PCR) analyses for evaluating SERT mRNA levels.
  • Western blotting techniques were used to detect levels of the SERT protein.
  • The researchers also used flow cytometry to examine the presence of SERT in leukocytes.
  • The functionality of SERT on leukocytes was examined using paroxetine, a medication that inhibits the reuptake of serotonin.

Key Findings

  • The results showed a significant decrease in levels of SERT in both leukocytes and platelets, following exercise.
  • There was a significant increase in the levels of serotonin in plasma.
  • Flow cytometry analysis revealed that the SERT protein is functional in a specific, yet unidentified, subpopulation of horse leukocytes, and that paroxetine successfully blocked the reuptake of serotonin into these leukocytes.
  • The researchers suggest that the physical exercise may have induced an increase in the release of free-tryptophan (a precursor of serotonin) and thus a release of serotonin from the stores in the blood.
  • Increased concentrations of serotonin in plasma could have resulted in a reduction in SERT expression, affecting cellular serotonin storage and uptake.
  • The treadmill exercise in the study did not result in a significant increase in cortisol levels.
  • The study concludes that physical exercise modulates peripheral serotonin metabolism, which implies that exercise influences the way serotonin is processed outside the brain.
  • The authors call for more research into the physiological implications of these findings.

Cite This Article

APA
D'Ascola A, Bruschetta G, Zanghì G, Campo S, Medica P, Campana S, Ferlazzo G, Gibbs BF, Ferlazzo AM. (2018). Changes in plasma 5-HT levels and equine leukocyte SERT expression in response to treadmill exercise. Res Vet Sci, 118, 184-190. https://doi.org/10.1016/j.rvsc.2018.02.012

Publication

ISSN: 1532-2661
NlmUniqueID: 0401300
Country: England
Language: English
Volume: 118
Pages: 184-190
PII: S0034-5288(17)30190-X

Researcher Affiliations

D'Ascola, Angela
  • Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Via Consolare Valeria 1, 98124 Messina, Italy. Electronic address: adascola@unime.it.
Bruschetta, Giuseppe
  • Department of Veterinary Sciences, University of Messina, Polo Universitario dell'Annunziata, 98168 Messina, Italy. Electronic address: gbruschetta@unime.it.
Zanghì, Gabriella
  • Department of Veterinary Sciences, University of Messina, Polo Universitario dell'Annunziata, 98168 Messina, Italy.
Campo, Salvatore
  • Department of Biomedical Sciences and Morphological and Functional Images, University of Messina, Via Consolare Valeria 1, 98124 Messina, Italy. Electronic address: scampo@unime.it.
Medica, Pietro
  • Department of Veterinary Sciences, University of Messina, Polo Universitario dell'Annunziata, 98168 Messina, Italy. Electronic address: pmedica@unime.it.
Campana, Stefania
  • Department of Human Pathology, University of Messina, Via Consolare Valeria 1, 98124 Messina, Italy.
Ferlazzo, Guido
  • Department of Human Pathology, University of Messina, Via Consolare Valeria 1, 98124 Messina, Italy. Electronic address: guido.ferlazzo@unime.it.
Gibbs, Bernhard F
  • Medway School of Pharmacy, University of Kent, ME4 4TB Chatham Maritime, United Kingdom. Electronic address: B.F.Gibbs@kent.ac.uk.
Ferlazzo, Alida Maria
  • Department of Veterinary Sciences, University of Messina, Polo Universitario dell'Annunziata, 98168 Messina, Italy. Electronic address: alferl@unime.it.

MeSH Terms

  • Animals
  • Blood Platelets
  • Brain
  • Exercise Test / veterinary
  • Horses
  • Leukocytes / metabolism
  • Physical Conditioning, Animal / physiology
  • Serotonin / blood
  • Serotonin Plasma Membrane Transport Proteins / metabolism

Citations

This article has been cited 13 times.
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