Exosome and miRNA content engagement in the physical exercise response: what is known to date in atheltic horses?

To date, there is extensive scientific evidence affirming that physical exercise plays a fundamental role in both the prevention and treatment of various pathological conditions in humans as well as in animals. It is understood that the advantages of movement and exercise have a multifactorial origin and they depend on a category of bioactive molecules vehicolated by extracellular microvesicles known as exosomes. The exosomes act as potential delivery systems for messages within the organism. These findings have drawn significant attention, leading researchers to further investigate the role of exosomes, delving into the study of microRNAs (miRNAs). In particular, these molecules are found inside exosomes and play a key role in cellular communication, with an impact on numerous physiological functions of the organism. It has been suggested that during physical exercise, the expression levels of miRNAs increase in parallel with those of exosomes, and their release enables intercellular communication in multicellular organisms, thereby regulating both cell growth and division. Studies have not only been carried out in humans, but also in laboratory animals and in mammals following exercise. Specifically, a change in exosome expression has been found in athletic horses following physical exercise. The aim of the current review was to highlight what is known about the role played by exosomes and miRNAs during physical exercise in equine species by considering, on a broad scale, the published data on this topic, including comparative data from humans and rodent models.