Novel Strategies to Improve the Cardioprotective Effects of Cardioplegia.

The use of cardioprotective strategies as adjuvants of cardioplegic solutions has become an ideal alternative for the improvement of post-surgery heart recovery. The choice of the optimal cardioplegia, as well as its distribution mechanism, remains controversial in the field of cardiovascular surgery. There is still a need to search for new and better cardioprotective methods during cardioplegic procedures. New techniques for the management of cardiovascular complications during cardioplegia have evolved with new alternatives and additives, and each new strategy provides a tool to neutralize the damage after ischemia/reperfusion events. Researchers and clinicians have committed themselves to studying the effect of new strategies and adjuvant components with the potential to improve the cardioprotective effect of cardioplegic solutions in preventing myocardial ischemia/reperfusion-induced injury during cardiac surgery. The aim of this review is to explore the different types of cardioplegia, their protection mechanisms, and which strategies have been proposed to enhance the function of these solutions in hearts exposed to cardiovascular pathologies that require surgical alternatives for their corrective progression.

HERPUD1 governs tumor cell mitochondrial function via inositol 1,4,5-trisphosphate receptor-mediated calcium signaling.

The intricate relationship between calcium (Ca2+) homeostasis and mitochondrial function is crucial for cellular metabolic adaptation in tumor cells. Ca2+-initiated signaling maintains mitochondrial respiratory capacity and ATP synthesis, influencing critical cellular processes in cancer development. Previous studies by our group have shown that the homocysteine-inducible ER Protein with Ubiquitin-Like Domain 1 (HERPUD1) regulates inositol 1,4,5-trisphosphate receptor (ITPR3) levels and intracellular Ca2+ signals in tumor cells. This study explores the role of HERPUD1 in regulating mitochondrial function and tumor cell migration by controlling ITPR3-dependent Ca2+ signals. We found HERPUD1 levels correlated with mitochondrial function in tumor cells, with HERPUD1 deficiency leading to enhanced mitochondrial activity. HERPUD1 knockdown increased intracellular Ca2+ release and mitochondrial Ca2+ influx, which was prevented using the ITPR3 antagonist xestospongin C or the Ca2+ chelator BAPTA-AM. Furthermore, HERPUD1 expression reduced tumor cell migration by controlling ITPR3-mediated Ca2+ signals. HERPUD1-deficient cells exhibited increased migratory capacity, which was attenuated by treatment with xestospongin C or BAPTA-AM. Additionally, HERPUD1 deficiency led to reactive oxygen species-dependent activation of paxillin and FAK proteins, which are associated with enhanced cell migration. Our findings highlight the pivotal role of HERPUD1 in regulating mitochondrial function and cell migration by controlling intracellular Ca2+ signals mediated by ITPR3. Understanding the interplay between HERPUD1 and mitochondrial Ca2+ regulation provides insights into potential therapeutic targets for cancer treatment and other pathologies involving altered energy metabolism.

Factor de crecimiento análogo a insulina-1 y cardiotrofina-1 inducido por ejercicio y su relación con hipertrofia miocárdica en maratonistas

Antecedentes: El ejercicio de alta intensidad induce hipertrofia miocárdica necesaria para adaptar al corazón a la mayor demanda de trabajo. Se desconoce si correr una maratón induce de forma aguda factores humorales asociados al desarrollo de hipertrofia miocárdica en atletas. Objetivo: Evaluar cardiotrofina-1 (CT1) y el factor de crecimiento análogo a insulina-1 (IGF-1), conocidos inductores de hipertrofia, en maratonistas previo y justo después de correr una maratón y su relación con hipertrofia cardíaca. Métodos: Estudio prospectivo ciego simple de atletas hombres que corrieron la maratón de Santiago. Se incluyó un grupo control sedentario. En todos los sujetos se realizó un ecocardiograma transtorácico estándar. Los niveles de CT1 e IGF-1 se determinaron en plasma obtenidos antes (basal) y justo después de haber terminado (antes de 15 minutos) la maratón, usando test de ELISA. Resultados: Los atletas tenían frecuencias cardíacas menores que los controles, asociado con una mayor hipertrofia miocárdica, determinado por el grosor del septo y pared posterior del corazón, y volúmenes del ventrículo y aurícula izquierda. Los niveles basales de CT1 e IGF-1 fueron similares entre atletas y controles sedentarios. El correr la maratón aumentó los niveles de estas dos hormonas en un subgrupo de atletas. Solo los atletas que incrementaron los niveles de IGF-1, pero no de CT1, tenían volúmenes de ventrículo izquierdo y derecho más grandes que los otros atletas. Conclusiones: IGF-1 que se incrementa de forma aguda por el ejercicio, pero no CT1, estaría asociado con el aumento de los volúmenes ventriculares observado en los atletas.

Background: High intensity exercise induces the development of myocardial hypertrophy necessary to adapt the heart to the increased work demand. Whether running a marathon is associated with acutely induced humoral factors responsible for the development of myocardial hypertrophy observed in athletes is not known. Objective: To evaluate the levels of cardiotrophin-1 (CT1) and insulin-like growth factor-1 (IGF-1), known hypertrophy inducers, in marathon runners before and just after running a marathon and their relationship with cardiac hypertrophy. Methodology: Single-blind prospective study of male athletes who ran the Santiago's marathon. A sedentary control group was included. All subjects underwent a standard transthoracic echocardiogram. CT1 and IGF-1 levels were determined in plasma obtained before (basal) and just after finishing (within 15 min) the marathon using ELISA assays. Results: Athletes had lower heart rates than controls, associated with greater myocardial hypertrophy, as determined by thickness of the heart's septum and posterior wall, and left atrial and ventricular volumes. Basal CT1 and IGF-1 levels were similar between athletes and sedentary controls. Marathon running increased the levels of these two hormones in a subgroup of athletes. Only the athletes who increased IGF-1 levels, but not CT1, had larger left and right ventricular volumes. Conclusion: IGF-1 acutely increased by exercise, but not CT1, was associated with the augmented ventricular volumes observed in athletes.

Estrogen signaling as a bridge between the nucleus and mitochondria in cardiovascular diseases.

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Epidemiological studies indicate that pre-menopausal women are more protected against the development of CVDs compared to men of the same age. This effect is attributed to the action/effects of sex steroid hormones on the cardiovascular system. In this context, estrogen modulates cardiovascular function in physiological and pathological conditions, being one of the main physiological cardioprotective agents. Here we describe the common pathways and mechanisms by which estrogens modulate the retrograde and anterograde communication between the nucleus and mitochondria, highlighting the role of genomic and non-genomic pathways mediated by estrogen receptors. Additionally, we discuss the presumable role of bromodomain-containing protein 4 (BRD4) in enhancing mitochondrial biogenesis and function in different CVD models and how this protein could act as a master regulator of estrogen protective activity. Altogether, this review focuses on estrogenic control in gene expression and molecular pathways, how this activity governs nucleus-mitochondria communication, and its projection for a future generation of strategies in CVDs treatment.

Mitochondrial E3 ubiquitin ligase 1 (MUL1) as a novel therapeutic target for diseases associated with mitochondrial dysfunction.

Mitochondrial E3 ubiquitin ligase 1 (MUL1) is a mitochondrial outer membrane-anchored protein-containing transmembrane domain in its N- and C-terminal regions, where both are exposed to the cytosol. Interestingly the C-terminal region has a RING finger domain responsible for its E3 ligase activity, as ubiquitin or in SUMOylation, interacting with proteins related to mitochondrial fusion and fission, cell survival, and tumor suppressor process, such as Akt. Therefore, MUL1 is involved in various cellular processes, such as mitochondrial dynamics, inter-organelle communication, proliferation, mitophagy, immune response, inflammation and cell apoptosis. MUL1 is expressed at a higher basal level in the heart, immune system organs, and blood. Here, we discuss the role of MUL1 in mitochondrial dynamics and its function in various pathological models, both in vitro and in vivo. In this context, we describe the role of MUL1 in: (1) the inflammatory response, by regulating NF-κB activity; (2) cancer, by promoting cell death and regulating exonuclear function of proteins, such as p53; (3) neurological diseases, by maintaining communication with other organelles and interacting with proteins to eliminate damaged organelles and; (4) cardiovascular diseases, by maintaining mitochondrial fusion/fission homeostasis. In this review, we summarize the latest advances in the physiological and pathological functions of MUL1. We also describe the different substrates of MUL1, acting as a positive or negative regulator in various pathologies associated with mitochondrial dysfunction. In conclusion, MUL1 could be a potential key target for the development of therapies that focus on ensuring the functionality of the mitochondrial network and, furthermore, the quality control of intracellular components by synchronously modulating the activity of different cellular mechanisms involved in the aforementioned pathologies. This, in turn, will guide the development of targeted therapies.

Polycystin-1 regulates cardiomyocyte mitophagy.

Polycystin-1 (PC1) is a transmembrane protein found in different cell types, including cardiomyocytes. Alterations in PC1 expression have been linked to mitochondrial damage in renal tubule cells and in patients with autosomal dominant polycystic kidney disease. However, to date, the regulatory role of PC1 in cardiomyocyte mitochondria is not well understood. The analysis of mitochondrial morphology from cardiomyocytes of heterozygous PC1 mice (PDK1+/- ) using transmission electron microscopy showed that cardiomyocyte mitochondria were smaller with increased mitochondria density and circularity. These parameters were consistent with mitochondrial fission. We knocked-down PC1 in cultured rat cardiomyocytes and human-induced pluripotent stem cells (iPSC)-derived cardiomyocytes to evaluate mitochondrial function and morphology. The results showed that downregulation of PC1 expression results in reduced protein levels of sub-units of the OXPHOS complexes and less functional mitochondria (reduction of mitochondrial membrane potential, mitochondrial respiration, and ATP production). This mitochondrial dysfunction activates the elimination of defective mitochondria by mitophagy, assessed by an increase of autophagosome adapter protein LC3B and the recruitment of the Parkin protein to the mitochondria. siRNA-mediated PC1 knockdown leads to a loss of the connectivity of the mitochondrial network and a greater number of mitochondria per cell, but of smaller sizes, which characterizes mitochondrial fission. PC1 silencing also deregulates the AKT-FoxO1 signaling pathway, which is involved in the regulation of mitochondrial metabolism, mitochondrial morphology, and processes that are part of cell quality control, such as mitophagy. Together, these data provide new insights about the controls that PC1 exerts on mitochondrial morphology and function in cultured cardiomyocytes dependent on the AKT-FoxO1 signaling pathway.

VCAM-1 as a predictor biomarker in cardiovascular disease.

The vascular cellular adhesion molecule-1 (VCAM-1) is a protein that canonically participates in the adhesion and transmigration of leukocytes to the interstitium during inflammation. VCAM-1 expression, together with soluble VCAM-1 (sVCAM-1) induced by the shedding of VCAM-1 by metalloproteinases, have been proposed as biomarkers in immunological diseases, cancer, autoimmune myocarditis, and as predictors of mortality and morbidity in patients with chronic heart failure (HF), endothelial injury in patients with coronary artery disease, and arrhythmias. This revision aims to discuss the role of sVCAM-1 as a biomarker to predict the occurrence, development, and preservation of cardiovascular disease.

Impact of the Potential Antitumor Agent 2-(4-Hydroxyphenyl) Amino-1,4-Naphthoquinone (Q7) on Vasomotion Is Mediated by the Vascular Endothelium, But Not Vascular Smooth Muscle Cell Metabolism.

ABSTRACT: Vasomotion is defined as rhythmic oscillations in arterial diameter that regulate the blood flow and blood pressure. Because antitumor treatment may impair vascular functions and increase the blood pressure, we sought to evaluate whether a new naphthoquinone derivative, postulated as an antitumor agent, manifests adverse effects on vascular function. In this article, we evaluated the toxicity of 2-(4-hydroxyphenyl) amino-1,4-naphthoquinone (Q7) and its effects on vascular vasomotion in 3 models of vascular structure: endothelial cells, aortic ring, and smooth muscle cells. Although showing nontoxic effects, Q7 inhibited the formation of capillary-like structures of the EA.hy926 endothelial cell line grown on Matrigel. In exvivo experiments with aortic rings precontracted with phenylephrine (PE, 10-6 M), Q7 (10-5 M) significantly (P < 0.05) reduced vascular rhythmic contractions induced by the acetylcholine (ACh; 10-7-10-5 M), whereas sodium nitroprusside (a nitric oxide donor; 10-8 M) recovered the vasomotion. Furthermore, Q7 (10-5 M) did not decrease KCl-induced vascular rhythmic contractions in the aortic rings precontracted with BaCl2 (a nonselective K+ channel blocker; 10-3 M). Vascular smooth muscle cells (A7r5) preincubated with Q7 (10-5 M) for 3 hours also demonstrated a reduced glucose uptake. However, the Adenosine Triphosphate content was unaffected, suggesting that the rapid reduction in vasomotion observed in vascular reactivity experiments did not involve cellular metabolism but may be due to faster mechanisms involving endothelial nitric oxide and K+ channels leading to oscillations in intracellular Ca2+. In summary, the naphthoquinone derivative Q7 presents low cytotoxicity yet may alter the endothelial cell response and vasomotion in the absence of changes in smooth muscle cell metabolism.

Angiotensin-(1-7) Prevents Lipopolysaccharide-Induced Autophagy via the Mas Receptor in Skeletal Muscle.

Skeletal muscle atrophy, which occurs in lipopolysaccharide (LPS)-induced sepsis, causes a severe muscle function reduction. The increased autophagy contributes to sepsis-induced skeletal muscle atrophy in a model of LPS injection, increasing LC3II/LC3I ratio, autophagy flux, and autophagosomes. Angiotensin-(1-7) (Ang-(1-7)) has anti-atrophic effects via the Mas receptor in skeletal muscle. However, the impact of Ang-(1-7) on LPS-induced autophagy is unknown. In this study, we determined the effect of Ang-(1-7) on sepsis-induced muscle autophagy. C57BL6 wild-type (WT) mice and mice lacking the Mas receptor (KO Mas) were injected with LPS together with the systemic administration of Ang-(1-7) to determine autophagy in skeletal muscle. We also evaluated autophagy and p38 and c-Jun N-terminal kinase (JNK)activation. Our results show that Ang-(1-7) prevents LPS-induced autophagy in the diaphragm, tibialis anterior, and gastrocnemius of WT mice, which is demonstrated by a decrease in the LC3II/LC3I ratio and mRNA levels of lc3b and ctsl. This effect was lost in KO Mas mice, suggesting the role of the Mas receptor. The results in C2C12 cells show that Ang-(1-7) reduces several LPS-dependent effects, such as autophagy (LC3II/LC3I ratio, autophagic flux, and autophagosomes), activation of p38 and JNK, B-cell lymphoma-2 (BCL2) phosphorylation, and disassembly of the Beclin1/BCL2 complex. In conclusion, Ang-(1-7)/Mas receptor reduces LPS-induced autophagy in skeletal muscle. In vitro assays indicate that Ang-(1-7) prevents LPS-induced autophagy and modifies the MAPK signaling and the disassembly of a complex involved at the beginning of autophagy.

Preoperative soluble VCAM-1 contributes to predict late mortality after coronary artery surgery.

BACKGROUND: Soluble vascular cell adhesion molecule-1 has been associated with long-term cardiovascular mortality in patients with stable coronary artery disease and to the development of new atrial fibrillation in subjects with cardiovascular risk factors but no evidence of cardiac disease. HYPOTHESIS: Preoperative soluble vascular cell adhesion molecule-1 predicts the risk of future all-cause death and cardiovascular death among patients submitted to elective coronary artery bypass surgery. METHODS: From a cohort of 312 patients who underwent elective coronary artery bypass surgery prospectively followed for a median of 6.7 years, we evaluated the prognostic role of preoperative soluble vascular cell adhesion molecule-1, inflammatory markers, CHA2DS2-VASc score and development of postoperative atrial fibrillation (POAF). Univariable and multivariable Cox regression analyses were performed to establish an association of these parameters with long term all-cause death and cardiovascular death. RESULTS: During 2112 person-years of follow-up, we observed 41 deaths, 10 were cardiovascular deaths. Independently increased levels of preoperative soluble vascular cell adhesion molecule-1, POAF, and CHA2DS2-VASc score were associated with all-cause mortality. After multivariate adjustment, elevated preoperative soluble vascular cell adhesion molecule-1 and POAF were the only independent predictors of all-cause death. Also, preoperative soluble vascular cell adhesion molecule-1, POAF, and CHA2DS2-VASc score resulted in being independent predictors of cardiovascular mortality. CONCLUSIONS: Increased circulating levels of preoperative soluble vascular cell adhesion molecule-1, together with POAF and CHA2DS2-VASc score, were significantly associated with future all-cause death and cardiovascular death among patients submitted to coronary artery bypass surgery.

Antihipertensivos en pacientes con COVID-19 / Anti hypertensive agents in patients with COVID-19

En 31 de diciembre del 2019 la Organización Mundial de la Salud fue informada por las autoridades sanitarias chinas de la aparición de casos de neumonía de origen desconocido en la ciudad de Wuhan en China. El 7 de Enero de 2020, científicos chinos identificaron a un nuevo coronavirus (temporalmente designado como "2019-nCoV") como el agente etiológico de la enfermedad denominada COVID-19. La secuenciación del genoma del nuevo coronavirus mostró gran similitud con el coronavirus (Covid-1 o SARS-CoV) causante del síndrome respiratorio agudo severo (SARS), ocurrido también en China entre los años 2002-2003. Por este motivo, 2019-nCoV se rebautizó como SARS-CoV-2 (Severe Acute Respiratory Syndrome Corona Virus-2) y a la fecha es responsable de la actual y grave pandemia que está ocasionando impactos sanitarios y socio-económicos a escala global. Las investigaciones con SARS-CoV establecieron que este virus ingresa a nuestras células utilizando como receptor a la enzima convertidora de angiotensina tipo 2 (ECA 2 o en inglés ACE-2: "angiotensin converting enzyme type 2"). Dado este antecedente también se confirmó que SARS-CoV-2 también utiliza esta misma enzima ya que no se habla de un mecanismo en si para ingresar a sus células blanco, especialmente a nivel de nuestro sistema respiratorio. ECA-2 es una proteasa integrante del sistema renina angiotensina "alterno o no canónico" con importantes acciones regulatorias sobre los sistemas cardiovascular, renal y pulmonar, entre otros. En este contexto, ha surgido preocupación tanto por clínicos como los propios pacientes respecto al estado de pacientes hipertensos con COVID-19 y su vulnerabilidad a infectarse con SARS-CoV-2 dado que algunos trabajos han planteado que ciertos polimorfismos en el gen ECA-2 asociados a hipertensión arterial podrían determinar una mayor expresión de ECA-2. Además, estudios preclínicos han sugerido que ciertos fármacos antihipertensivos (principalmente, inhibidores de ECA y antagonistas del receptor para angiotensina II subtipo 1) también podrían estimular una mayor expresión de ECA-2. Esta revisión tiene por objetivo presentar y discutir los antecedentes en el estado del arte respecto a esta reciente problemática. El análisis crítico de los presentes antecedentes permite concluir que no existe evidencia clínica sólida que permita afirmar que el uso de medicamentos antihipertensivos genere una mayor vulnerabilidad a la infección con SARS-CoV-2. Por lo tanto no se debe descontinuar su uso en pacientes hipertensos en riesgo de infección a SARS-CoV-2 o que padezcan COVID-19.

In December 2019, a new type of coronavirus emerged in the city of Wuhan, China. This novel virus has unleashed a pandemic that has inflicted a considerable impact on public health and the economy and has therefore become a severe concern worldwide. This new virus -named SARS-CoV-2has been rapidly investigated in order to create knowledge aimed at achieving its control. Comparative studies with SARS-CoV virus, responsible for the 2002-2003 pandemic, suggest that SARS-CoV-2 requires the same receptor to bind and infect cells: angiotensin converting enzyme 2 (ACE-2). This hypothesis has been thoroughly supported by a variety of in vitro research and is currently considered a potential therapeutic target. ACE-2 is part of the counter-regulatory renin-angiotensin system, exerting effects in pulmonary, renal and cardiovascular systems. In this context, concerns have arisen in regards to the vulnerability of hypertensive patients against COVID-19, given that there is evidence that may suggest that polymorphisms associated to hypertension may increase the expression of ACE-2. Moreover, preclinical studies have shown that antihypertensive drugs may increase the expression of this enzyme. In this review article, we present the current state of the art on this polemic topic. Our critical analysis suggest that there is no robust clinical evidence supporting the hypothesis that the use of antihypertensive drugs can increase vulnerability to infection with SARS-CoV-2. Therefore, we recommend that the use of these therapeutic agents should not be discontinued in hypertensive patients in risk to or suffering COVID-19.

Angiotensin-(1-9) prevents cardiomyocyte hypertrophy by controlling mitochondrial dynamics via miR-129-3p/PKIA pathway.

Angiotensin-(1-9) is a peptide from the noncanonical renin-angiotensin system with anti-hypertrophic effects in cardiomyocytes via an unknown mechanism. In the present study we aimed to elucidate it, basing us initially on previous work from our group and colleagues who proved a relationship between disturbances in mitochondrial morphology and calcium handling, associated with the setting of cardiac hypertrophy. Our first finding was that angiotensin-(1-9) can induce mitochondrial fusion through DRP1 phosphorylation. Secondly, angiotensin-(1-9) blocked mitochondrial fission and intracellular calcium dysregulation in a model of norepinephrine-induced cardiomyocyte hypertrophy, preventing the activation of the calcineurin/NFAT signaling pathway. To further investigate angiotensin-(1-9) anti-hypertrophic mechanism, we performed RNA-seq studies, identifying the upregulation of miR-129 under angiotensin-(1-9) treatment. miR-129 decreased the transcript levels of the protein kinase A inhibitor (PKIA), resulting in the activation of the protein kinase A (PKA) signaling pathway. Finally, we showed that PKA activity is necessary for the effects of angiotensin-(1-9) over mitochondrial dynamics, calcium handling and its anti-hypertrophic effects.

Counter-regulatory renin-angiotensin system in cardiovascular disease.

The renin-angiotensin system is an important component of the cardiovascular system. Mounting evidence suggests that the metabolic products of angiotensin I and II - initially thought to be biologically inactive - have key roles in cardiovascular physiology and pathophysiology. This non-canonical axis of the renin-angiotensin system consists of angiotensin 1-7, angiotensin 1-9, angiotensin-converting enzyme 2, the type 2 angiotensin II receptor (AT2R), the proto-oncogene Mas receptor and the Mas-related G protein-coupled receptor member D. Each of these components has been shown to counteract the effects of the classical renin-angiotensin system. This counter-regulatory renin-angiotensin system has a central role in the pathogenesis and development of various cardiovascular diseases and, therefore, represents a potential therapeutic target. In this Review, we provide the latest insights into the complexity and interplay of the components of the non-canonical renin-angiotensin system, and discuss the function and therapeutic potential of targeting this system to treat cardiovascular disease.

Polyphenolic Composition and Hypotensive Effects of Parastrephia quadrangularis (Meyen) Cabrera in Rat.

Parastrephia quadrangularis (Pq), commonly called "Tola", is widely used in folk medicine in the Andes, including for altitude sickness. In this study, polyphenolic composition was determined, and hypotensive effects were measured; the ethnopharmacological use as hypotensive was related to the presence of phenolic compounds. For this purpose, male Sprague-Dawley rats (6 to 8 weeks of age, 160 to 190 g) were fed Pq extract (10 to 40 mg/kg) for 10 days through gavage. Blood pressures and heart rate were significantly (p < 0.01) reduced in normotensive rats receiving Pq extract (40 mg/kg body weight). Pq extract induced a negative inotropic effect, and endothelium-dependent vasodilation mediated by nitric oxide (NO). Furthermore, preincubation with Pq extract significantly decreased the cytosolic calcium on vascular smooth muscle cells A7r5 in response to L-phenylephrine (PE). Seven metabolites were isolated from the Pq extract, but three flavonoids (10-4 M) showed similar vasodilation to the extract in intact rat aorta as follows: 5,3',4'-trihydroxy-7-methoxyflavanone (2); 3,5,4'-trihydroxy-7,8,3'-trimethoxyflavone (6); and 5,4'-dihydroxy-3,7,8,3'-tetramethoxyflavone (7). The Pq extract and compounds 2 and 7 significantly (p < 0.05) reduced the contraction to Bay K8644 (10 nM, an agonist of CaV1.2 channels). Administration of Pq decreased cardiac contractility and increased endothelium-dependent and -independent vasodilation.

AT2 Receptor Mediated Activation of the Tyrosine Phosphatase PTP1B Blocks Caveolin-1 Enhanced Migration, Invasion and Metastasis of Cancer Cells.

: The renin-angiotensin receptor AT2R controls systemic blood pressure and is also suggested to modulate metastasis of cancer cells. However, in the latter case, the mechanisms involved downstream of AT2R remain to be defined. We recently described a novel Caveolin-1(CAV1)/Ras-related protein 5A (Rab5)/Ras-related C3 botulinum toxin substrate 1 (Rac1) signaling axis that promotes metastasis in melanoma, colon, and breast cancer cells. Here, we evaluated whether the antimetastatic effect of AT2R is connected to inhibition of this pathway. We found that murine melanoma B16F10 cells expressed AT2R, while MDAMB-231 human breast cancer cells did not. AT2R activation blocked migration, transendothelial migration, and metastasis of B16F10(cav-1) cells, and this effect was lost when AT2R was silenced. Additionally, AT2R activation reduced transendothelial migration of A375 human melanoma cells expressing CAV1. The relevance of AT2R was further underscored by showing that overexpression of the AT2R in MDA-MB-231 cells decreased migration. Moreover, AT2R activation increased non-receptor protein tyrosine phosphatase 1B (PTP1B) activity, decreased phosphorylation of CAV1 on tyrosine-14 as well as Rab5/Rac1 activity, and reduced lung metastasis of B16F10(cav-1) cells in C57BL/6 mice. Thus, AT2R activation reduces migration, invasion, and metastasis of cancer cells by PTP1B-mediated CAV1 dephosphorylation and inhibition of the CAV1/Rab5/Rac-1 pathway. In doing so, these observations open up interesting, novel therapeutic opportunities to treat metastatic cancer disease.

Biomarcadores de fibrosis y función ventricular derecha en maratonistas con distinto grado de entrenamiento: estudio en la maratón de Santiago / Fibrosis and right ventricular function biomarkers in marathon runners: a study at the Santiago, Chile marathon

Resumen: Introducción: Atletas altamente entrenados muestran cambios cardíacos estructurales como adaptación a la sobrecarga, producto del ejercicio repetitivo y extenuante. Se han evidenciado elevación de biomarcadores de remodelado y fibrosis miocárdica posterior al ejercicio intenso en atletas. Sin embargo, el comportamiento de estos biomarcadores según el nivel de entrenamiento previo no se ha evaluado. Objetivo: Investigar biomarcadores de fibrosis y función ventricular derecha en maratonistas con distinto nivel de entrenamiento previo. Métodos: Se incluyeron 36 maratonistas hombres, sanos, que completaron 42 km en la maratón de Santiago. Se dividieron según entrenamiento previo en dos grupos, Grupo 1 (G1): ≥100 km/semana y Grupo 2 (G2): <100 km/semana. Se realizó ecocardiografía transtorácica y se evaluaron niveles plasmáticos de galectina-3 y del propéptido amino terminal del procolágeno tipo III (PIIINP) en la semana previa a la carrera e inmediatamente posterior a ésta. Resultados: Posterior a la maratón, la función sistólica del ventrículo derecho disminuyó en el grupo G2 junto con un aumento significativo de los niveles plasmáticos de PIIIPNP (61±16 a 94±24 ng/mL, p=0,01). Estos cambios no se observaron en el grupo G1 (65 ± 11 a 90±29 ng/mL, p=0,10). Los niveles plasmáticos de galectina-3 aumentaron significativamente en ambos grupos posterior al ejercicio (6,8±2,2 a 19,7±4,9 ng/mL, p 0,012 y 6,0±1,1 a 19,4 ± 5,9 ng/mL, p 0,01) en los grupos G1 y G2, respectivamente). Conclusiones: Atletas con menor grado de entrenamiento, presentan posterior a una maratón un significativo aumento de productos de degradación del colágeno (PIIIPNP) asociado a disminución de la función del ventrículo derecho. Los niveles de galectina-3 plasmática aumentan significativamente en ambos grupos post-esfuerzo independiente del entrenamiento previo.

Abstracts: Introduction: Highly trained athletes show structural cardiac changes as adaptation to overload. Rise in remodeling biomarkers and myocardial fibrosis after intense exercise in athletes has been evidenced; however, the behavior of these biomarkers according to pre-competition training level has not been evaluated. Objective: To evaluate fibrosis biomarkers levels and right ventricle function in marathon runners according to their previous training level, in the period prior to a marathon race and immediately after it. Methods: Thirty-six healthy male marathon runners were included. Subjects were grouped according to their previous training level: Group 1 (G1): ≥100 km/week and Group 2 (G2): <100 km/week. Transthoracic echocardiography along with plasmatic levels of galectin-3 and amino terminal propeptide of type III procollagen (PIIINP) were measured one week previous and immediately after the marathon. Results: Post-effort right ventricle systolic function decreased in G2, together with a significant elevation of PIIIPNP (61±16 to 94±24 ng/mL, p=0.01). These changes were not observed in G1 (from 65±11 to 90±29 ng/mL, p=0.10). Plasma galectin-3 increased significantly in both groups immediately post-exercise (6.8±2.2 to 19.7±4.9 ng/mL, p=0.012, and 6.0±1.1 to 19.4±5.9 ng/mL, p=0.01, in G1 and G2. respectively). Conclusion: Less trained athletes evidenced higher post marathon levels of PIIIPNP which is associated with a decreased global right ventricle function. Plasma galectin-3 levels increased significantly after intense exertion regardless of the intensity of previous training.

Entrenamiento físico de alta intensidad en maratonistas produce mayor remodelado cardíaco y reduce respuesta de estrés oxidativo / High-intensity training in marathon runners increases cardiac remodeling and diminishes oxidative stress response

Resumen: Introducción: El ejercicio físico reduce la mortalidad cardiovascular y genera remodelado cardíaco. Altas cargas de entrenamiento pueden generar remodelado cardíaco adverso. Biomarcadores (BMC) de inflamación Interleukina 6 (IL-6) y de estrés oxidativo Malondialdehído (MDA), potencialmente pueden caracterizar la respuesta al esfuerzo. Objetivo: Evaluar actividad de IL-6 y MDA en respuesta a una maratón en atletas con distinto nivel de entrenamiento y remodelado cardíaco asociado. Sujetos y Métodos: Estudio prospectivo, simple ciego, incluyó 16 atletas que completaron la maratón de Santiago (42 k), separados según entrenamiento previo, grupo 1 (G1, n: 8): Alto ≥ 100 km/semana y grupo 2 (G2, n: 8): Bajo <100 km/semana). Se obtuvo pre y post maratón: niveles de IL-6, MDA y ecocardiografía Doppler transtorácica (ETT); cuantificando cámaras cardíacas izquierdas, derechas y deformación del ventrículo izquierdo (strain longitudinal). Se utilizaron las pruebas de Mann-Whitney, Wilcoxon y Kruskal-Wallis. Resultados: Edad G1: 38.13±7.18 años vs G2: 40.38±6.63 años (NS). Tiempo maratón G1: 185.75±14.87 min vs G2: 219.75±24.92 min (p<0.01). Masa del ventrículo izquierdo G1: 91±21 g/m2 vs G2: 73±12 g/m2 (p<0.01). Volumen aurícula izquierda G1: 39.4±12.6 ml/m2 vs 30.6±4.6 ml/m2 (p<0.01). FEVI G1: 55.8±3.3% vs G2: 58.6±6.7% (NS). MDA G1: PRE 0.17±0.13 uM/L, POST 0.67±0.59 uM/L, G2: PRE 0.29±0.24 uM/L, POST 1.01±1.15 uM/L (p<0.01). IL-6 G1: PRE 2.50±1.35 pg/ml, POST 93.91±27.23 pg/ml vs G2: PRE 4.65±5.89 pg/ml, POST 97.83±30.72 pg/ml (NS). Conclusión: El ejercicio físico aumenta los BMC de inflamación y estés oxidativo (IL-6, MDA). Un entrenamiento físico de alta intensidad disminuye la respuesta de estrés oxidativo y se asocia a un mayor remodelado cardíaco.

Abstract: Background: Exercise reduces cardiovascular mortality and generates cardiac remodeling. High training loads can induce adverse cardiac remodeling, and its associated cardiac remodeling. Therefore, interleukin 6 (IL 6) and malondialdehyde (MDA), biomarkers of inflammatory response and oxidative stress respectively, may have a role in stratifying this risk. Objective: To assess the activity of IL-6 and MDA in response to a marathon race in athletes with different previous training status. Subjects And Methods: Prospective, single-blind study involving 16 male athletes that finished the Santiago Marathon (42 k), allocated into two groups according to their previous training: Group 1 (G1, n: 8) with high training (≥ 100 km/weekly) and Group 2 (G2, n: 8) with low training (< 100 km/weekly). Before and after the race serum levels of IL-6, MDA and transthoracic Doppler echocardiography for cardiac chamber quantification and left ventricle deformation (longitudinal strain) were measured. Mann-Whitney, Wilcoxon, and Kruskal-Wallis tests were used to assess statistical significance. Results: Age G1: 38.13±7.18 years-old vs G2: 40.38±6.63 years-old (NS). Marathon finishing time G1: 185.75±14.87 min vs G2: 219.75±24.92 min (p<0.01). Left ventricle mass G1: 91±21 g/m2 vs G2: 73±12 g/m2 (p<0.01). Left atrium volume G1: 39.4±12.6 ml/m2 vs 30.6±4.6 ml/m2 (p<0.01). LVEF G1: 55.8±3.3% vs G2: 58.6±6.7% (NS). MDA G1: PRE 0.17±0.13 uM/L, POST 0.67±0.59 uM/L, G2: PRE 0.29±0.24 uM/L, POST 1.01±1.15 uM/L (p<0.01). IL-6 G1: PRE 2.50±1.35 pg/ml, POST 93.91±27.23 vs G2: PRE 4.65±5.89 pg/ml, POST 97.83±30.72 pg/ml (NS). Conclusion: Physical exercise generates a rise in biomarkers (IL-6, MDA). Athletes with high-intensity training level have a diminished oxidative stress response post effort and greater cardiac remodeling.

Increased active phase atrial contraction is related to marathon runner performance.

PURPOSE: Left atrial (LA) contraction is essential for left ventricular (LV) filling during exertion. We sought to evaluate the relationship of LA contraction and exercise capacity in trained athletes. METHODS: Sixteen male marathon runners were recruited and allocated into two groups according to their previous training status (≥ or < 100 km peer week). All subjects underwent a baseline cardiopulmonary test to evaluate maximal aerobic capacity and a transthoracic echocardiography previous and immediate post-marathon. LA contractile function evaluation was accomplished by measuring the negative deformation of the post P wave strain curve (LASa). LASa change was defined as LASa pre-marathon minus LASa immediate post-marathon. RESULTS: Mean age was 39 ± 6 years. LA volume index (39 ± 13 vs. 31 ± 5 mL/m2, p = 0.04), LV mass index (91 ± 21 vs. 73 ± 12 g/m2, p = 0.04), VO2 max (59 ± 3 vs. 50 ± 8 mL/kg/min, p = 0.036) were higher in more intensive trained group and marathon time was lower (185 ± 14 vs. 219 ± 24 min, p = 0.017). An increase in LASa after immediate post-marathon was observed in both groups, which was significantly greater in the highly trained group (18.9 ± 5.8 vs. 6.3 ± 3.5%, p < 0.003). Maximum VO2 measured previous to the marathon was inversely related to marathon time and directly correlated to LASa change (rho = 0.744, p = 0.001, rho = 0.546, p = 0.028, respectively). CONCLUSIONS: Athletes with more intensive training load have larger LV mass and LA size. An increase in LA contraction was seen post-marathon, which was significantly greater in the highly trained group. This increase in the LA contraction was related to the maximum VO2 measured previous to the marathon and to performance in a highly demanding test.

Autophagy and oxidative stress in non-communicable diseases: A matter of the inflammatory state?

Non-communicable diseases (NCDs), also known as chronic diseases, are long-lasting conditions that affect millions of people around the world. Different factors contribute to their genesis and progression; however they share common features, which are critical for the development of novel therapeutic strategies. A persistently altered inflammatory response is typically observed in many NCDs together with redox imbalance. Additionally, dysregulated proteostasis, mainly derived as a consequence of compromised autophagy, is a common feature of several chronic diseases. In this review, we discuss the crosstalk among inflammation, autophagy and oxidative stress, and how they participate in the progression of chronic diseases such as cancer, cardiovascular diseases, obesity and type II diabetes mellitus.