Novel Insights into the Cardioprotective Effects of the Peptides of the Counter-Regulatory Renin-Angiotensin System.

Currently, cardiovascular diseases are a major contributor to morbidity and mortality worldwide, having a significant negative impact on both the economy and public health. The renin-angiotensin system contributes to a high spectrum of cardiovascular disorders and is essential for maintaining normal cardiovascular homeostasis. Overactivation of the classical renin-angiotensin system is one of the most important pathophysiological mechanisms in the progression of cardiovascular diseases. The counter-regulatory renin-angiotensin system is an alternate pathway which favors the synthesis of different peptides, including Angiotensin-(1-7), Angiotensin-(1-9), and Alamandine. These peptides, via the angiotensin type 2 receptor (AT2R), MasR, and MrgD, initiate multiple downstream signaling pathways that culminate in the activation of various cardioprotective mechanisms, such as decreased cardiac fibrosis, decreased myocardial hypertrophy, vasodilation, decreased blood pressure, natriuresis, and nitric oxide synthesis. These cardioprotective effects position them as therapeutic alternatives for reducing the progression of cardiovascular diseases. This review aims to show the latest findings on the cardioprotective effects of the main peptides of the counter-regulatory renin-angiotensin system.

Effects of Metformin on Ischemia/Reperfusion Injury: New Evidence and Mechanisms.

The search for new drugs with the potential to ensure therapeutic success in the treatment of cardiovascular diseases has become an essential pathway to follow for health organizations and committees around the world. In June 2021, the World Health Organization listed cardiovascular diseases as one of the main causes of death worldwide, representing 32% of them. The most common is coronary artery disease, which causes the death of cardiomyocytes, the cells responsible for cardiac contractility, through ischemia and subsequent reperfusion, which leads to heart failure in the medium and short term. Metformin is one of the most-used drugs for the control of diabetes, which has shown effects beyond the control of hyperglycemia. Some of these effects are mediated by the regulation of cellular energy metabolism, inhibiting apoptosis, reduction of cell death through regulation of autophagy and reduction of mitochondrial dysfunction with further reduction of oxidative stress. This suggests that metformin may attenuate left ventricular dysfunction induced by myocardial ischemia; preclinical and clinical trials have shown promising results, particularly in the setting of acute myocardial infarction. This is a review of the molecular and pharmacological mechanisms of the cardioprotective effects of metformin during myocardial ischemia-reperfusion injury.

No todo lo que sibila es asma: revisión de tema / Not everything that wheezes is asthma

Las sibilancias se definen como sonidos pulmonares adventicios, continuos y de tono alto. Predominantemente las sibilancias son de naturaleza espiratoria, pero también pueden ser inspiratorias o bifásicas. Su etiología es secundaria a la obstrucción de flujo en vía aérea superior extratorácica, vía aérea superior intratorácica o vía aérea inferior. Se cree que las sibilancias se deben a las vibraciones de las paredes de las vías respiratorias ocluidas, inducidas por una velocidad reducida del flujo de aire. Cuando se perciben sibilancias sin inducir exhalación forzada es necesario estudiar la causa, realizando una historia clínica dirigida a las diversas etiologías y un examen físico que incluya la exploración torácica completa: inspección, palpación, percusión y auscultación. Ayudas diagnósticas como la radiografía de tórax, la espirometría pre y posbroncodilatador, la tomografía computarizada de tórax y la broncoscopia pueden ser necesarias. El objetivo de este artículo es demostrar que las sibilancias representan un hallazgo semiológico retador para el clínico, que obliga no solo a pensar en asma o en enfermedad pulmonar obstructiva crónica (EPOC) como posible causa.

Wheezing is defined as adventitious, continuous and high-tone lung sounds. Predominantly the wheezing is of an expiratory nature, but it can also be inspiratory or biphasic. Its etiology is secondary to flow obstruction in the extrathoracic and intrathoracic upper airway, or lower airway. It is believed that wheezing is due to vibrations of the walls of the occluded airways, induced by a reduced speed of air flow. When wheezing is perceived without inducing forced exhalation, it is necessary to study the cause, perform a medical history directed at the various etiologies and a physical health check that includes complete chest examination: Inspection, palpation, percussion, and auscultation. As diagnostic aids like chest x-ray, pre- and post-bronchodilator spirometry, computed tomography of the chest and bronchoscopy may be necessary. The objective of this article is demonstrate that wheezing represents a challenging clinical finding for the medical doctor and suggests that it is important to consider other causes in addition to Asthma or Chronic Obstructive Pulmonary Disease (COPD).