Involvement of the TRPV1 channel in the modulation of spontaneous locomotor activity, physical performance and physical exercise-induced physiological responses

Abstract

Physical exercise triggers coordinated physiological responses to meet the augmented metabolic demand of contracting muscles. To provide adequate responses, the brain must receive sensory information about the physiological status of peripheral tissues and organs, such as changes in osmolality, temperature and pH. Most of the receptors involved in these afferent pathways express ion channels, including transient receptor potential (TRP) channels, which are usually activated by more than one type of stimulus and are therefore considered polymodal receptors. Among these TRP channels, the TRPV1 channel (transient receptor potential vanilloid type 1 or capsaicin receptor) has well-documented functions in the modulation of pain sensation and thermoregulatory responses. However, the TRPV1 channel is also expressed in non-neural tissues, suggesting that this channel may perform a broad range of functions. In this review, we first present a brief overview of the available tools for studying the physiological roles of the TRPV1 channel. Then, we present the relationship between the TRPV1 channel and spontaneous locomotor activity, physical performance, and modulation of several physiological responses, including water and electrolyte balance, muscle hypertrophy, and metabolic, cardiovascular, gastrointestinal, and inflammatory responses. Altogether, the data presented herein indicate that the TPRV1 channel modulates many physiological functions other than nociception and thermoregulation. In addition, these data open new possibilities for investigating the role of this channel in the acute effects induced by a single bout of physical exercise and in the chronic effects induced by physical training.

Capsaicin Supplementation Reduces Physical Fatigue and Improves Exercise Performance in Mice

“…TRPV1 activation by dietary capsaicin activates mitochondrial respiration, promotes mitochondrial biogenesis, and improves energy metabolism and exercise endurance by upregulating PGC-1α (peroxisome proliferator-activated receptor-γ coactivator-1α) in skeletal muscles [13,14]. TRPV1 channels may also participate in some chronic adaptations induced by regular physical exercise or training programs, including muscular hypertrophy and ATP production in muscle [15]. …”

“…Exhaustion theory suggests that energy source depletion and excess metabolite accumulation can lead to fatigue [18]. A previous article reviewed the physiological effects on energy metabolism and utilization via TRPV1 activation [15]. Therefore, we conducted this study to evaluate the potential ergogenic and anti-fatigue effects of CAP using our previously established in vivo platform [19,20].…”

Transient receptor potential channels and exercise‐associated muscle cramping: A tale of multiple complexities

“…The members of the TRP channel superfamily have several distinct, unique, and very complex regulatory, biophysical, and pharmacological properties, and their role in human physiology and pharmacology were recently reviewed . TRP ion channels function as molecular detectors of physical stimuli, with potential roles in numerous processes and systems including thermoregulation, the inflammatory and immune systems, the bronchopulmonary system, whole‐body metabolism and glucose homeostasis, cancer and tumorigenesis, pain, and GIT function . Three TRP family subtypes (TRPV1‐4, TRPA1, and TRPM8) are expressed in nociceptors in the skin and GIT, where they act as transducers for signals from temperature, chemical, and mechanical stimuli.…”

“…TRPV1 activation during exercise is very complex and may influence a number of physiological responses during exercise, including physical performance, thermoregulation, metabolism, the cardiovascular response to exercise, inflammation, water and electrolyte balance, and oxidative capacity of the muscle . The role of TRP channel activation (by agonists such as capsaicin), desensitization through single or repeated exposure to agonists, or suppression by antagonists during rest and exercise is very complex and not well understood.…”

Targeting TRPV1 to relieve motion sickness symptoms in mice by electroacupuncture and gene deletion

“…Among the 6 members, the transient receptor potential cation channel subfamily V member 1 (TRPV1) was the first to be isolated and is the most special, being characterized as a homotetrameric non-selective calcium-permeable cation channel 14 – 18 . Many reports have described the distribution of TRPV1 in widely expressed brain areas, including the thalamus, hypothalamus, hippocampus, amygdala, cerebellum, and dorsal root ganglia 17 , 19 , 20 . It is well known that TRPV1 plays an important role both in neuropathic and nociceptive pain as well as in inflammation, due to the fact that low pH (<6.0) and high temperature (>43 °C) are capable of activating TRPV1 channels 21 .…”