Exercise‐induced increases in inflammatory cytokines in muscle and blood of horses

The Effect of Exercise and Nutritional Supplementation on Proinflammatory Cytokine Expression in Young Racehorses During Training

“…This parallels our previous results following treadmill- [62] and race-based exercise studies [86]. The expression of IL-1b was exercise intensitydependent.…”

“…We did not see a significant increase in TNF-a mRNA expression at 2 hours after exercise, possibly because its expression had not yet peaked [62], although there is an overall trend for its expression to increase during the 2-hour sampling period. Limitations in the study design prevented us from collecting samples at later time points.…”

“…Equine athletes likewise exhibit altered inflammatory responses subsequent to exercise [22,62,63,[65][66][67][68]. The proposed mechanism for this exercise-induced inflammation is high-intensity traininginduced muscle, skeletal, or joint trauma [14,69].…”

“…Together, these multiple insults activate circulating monocytes and other cells to produce proinflammatory cytokines [74]. These changes in proinflammatory gene expression occur in skeletal muscle and peripheral blood cells [62]. Peripherally produced cytokines can in turn augment or exacerbate localized inflammatory responses in joints and muscles, thus leading to an amplification of the inflammatory cascade [10].…”

“…Total RNA was isolated from the PAXgene tubes and analyzed for gene expression of proinflammatory cytokines and Lymphokine activated Killer (LAK) cell markers using real-time polymerase chain reaction and equine-specific primers and probes (Table 3) [62]. The relative quantitation method was used to analyze gene expression where the average of all the horses' initial pretraining samples was used as a calibrator against which all subsequent samples were compared [63].…”