RESUMEN
Chronic obstructive pulmonary disease (COPD) and asthma are chronic respiratory diseases with high prevalence and mortality that significantly alter the quality of life in affected patients. While the cellular and molecular mechanisms engaged in the development and evolution of these two conditions are different, COPD and asthma share a wide array of symptoms and clinical signs that may impede differential diagnosis. However, the distinct signaling pathways regulating cough and airway hyperresponsiveness employ the interaction of different cells, molecules, and receptors. Transient receptor potential cation channel subfamily V member 1 (TRPV1) plays a major role in cough and airway inflammation. Consequently, its agonist, capsaicin, is of substantial interest in exploring the cellular effects and regulatory pathways that mediate these respiratory conditions. Increasingly more studies emphasize the use of capsaicin for the inhalation cough challenge, yet the involvement of TRPV1 in cough, bronchoconstriction, and the initiation of inflammation has not been entirely revealed. This review outlines a comparative perspective on the effects of capsaicin and its receptor in the pathophysiology of COPD and asthma, underlying the complex entanglement of molecular signals that bridge the alteration of cellular function with the multitude of clinical effects.
RESUMEN
Gastrointestinal (GI) cancers are a group of diseases with very high positions in the ranking of cancer incidence and mortality. While they show common features regarding the molecular mechanisms involved in cancer development, organ-specific pathophysiological processes may trigger distinct signaling pathways and intricate interactions with inflammatory cells from the tumoral milieu and mediators involved in tumorigenesis. The treatment of GI cancers is a topic of increasing interest due to the severity of these diseases, their impact on the patients' survivability and quality of life, and the burden they set on the healthcare system. As the efficiency of existing drugs is hindered by chemoresistance and adverse reactions when administered in high doses, new therapies are sought, and emerging drugs, formulations, and substance synergies are the focus of a growing number of studies. A class of chemicals with great potential through anti-inflammatory, anti-oxidant, and anti-tumoral effects is phytochemicals, and capsaicin in particular is the subject of intensive research looking to validate its position in complementing cancer treatment. Our paper thoroughly reviews the available scientific evidence concerning the effects of capsaicin on major GI cancers and its interactions with the molecular pathways involved in the course of these diseases.