TRPV1 Contributes to Modulate the Nitric Oxide Pathway and Oxidative Stress in the Isolated and Perfused Rat Heart during Ischemia and Reperfusion.

The transient vanilloid receptor potential type 1 (TRPV1) regulates neuronal and vascular functions mediated by nitric oxide (NO) and by the calcitonin gene-related peptide (CGRP). Here, we study the participation of TRPV1 in the regulation of myocardial injury caused by ischemia-reperfusion and in the control of NO, tetrahydrobiopterin (BH4), the cGMP pathway, CGRP, total antioxidant capacity (TAC), malondialdehyde (MDA) and phosphodiesterase-3 (PDE-3). Isolated hearts of Wistar rats perfused according to the Langendorff technique were used to study the effects of an agonist of TRPV1, capsaicin (CS), an antagonist, capsazepine (CZ), and their combination CZ+CS. The hearts were subjected to three conditions: (1) control, (2) ischemia and (3) ischemia-reperfusion. We determined cardiac mechanical activity and the levels of NO, cGMP, BH4, CGRP, TAC, MDA and PDE-3 in ventricular tissue after administration of CS, CZ and CZ+CS. Western blots were used to study the expressions of eNOS, iNOS and phosphorylated NOS (pNOS). Structural changes were determined by histological evaluation. CS prevented damage caused by ischemia-reperfusion by improving cardiac mechanical activity and elevating the levels of NO, cGMP, BH4, TAC and CGRP. TRPV1 and iNOS expression were increased under ischemic conditions, while eNOS and pNOS were not modified. We conclude that the activation of TRPV1 constitutes a therapeutic possibility to counteract the damage caused by ischemia and reperfusion by regulating the NO pathway through CGRP.

Effect of the Aged Garlic Extract on Cardiovascular Function in Metabolic Syndrome Rats.

The antioxidant properties of aged garlic extract (AGE) on cardiovascular functioning (CF) in metabolic syndrome (MS) remains poorly studied. Here we study the AGE effects on CF in a rat model of MS. Control rats plus saline solution (C + SS), MS rats (30% sucrose in drinking water from weaning) plus saline solution (MS + SS), control rats receiving AGE (C + AGE 125 mg/Kg/12 h) and MS rats with AGE (MS + AGE) were studied. MS + SS had increased triglycerides, systolic blood pressure, insulin, leptin, HOMA index, and advanced glycation end products. AGE returned their levels to control values (p < 0.01). Cholesterol was decreased by AGE (p = 0.05). Glutathion and GPx activity were reduced in MS + SS rats and increased with AGE (p = 0.05). Lipid peroxidation was increased in MS + SS and AGE reduced it (p = 0.001). Vascular functioning was deteriorated by MS (increased vasocontraction and reduced vasodilation) and AGE improved it (p = 0.001). Coronary vascular resistance was increased in MS rats and AGE decreased it (p = 0.001). Cardiac performance was not modified by MS but AGE increased it. NO measured in the perfusate liquid from the heart and serum citrulline, nitrites/nitrates were decreased in MS and AGE increased them (p < 0.01). In conclusion, AGE reduces MS-induced cardiovascular risk, through its anti-oxidant properties.

Garlic prevents the oxidizing and inflammatory effects of sepsis induced by bacterial lipopolysaccharide at the systemic and aortic level in the rat. Role of trpv1.

Garlic (Allium sativum) possesses healing properties for diseases like systemic arterial hypertension, cancer and diabetes, among others. Its main component, allicin, binds to the Transient Receptor Potential Vanilloid Type 1 (TRPV1). In this study, we investigated TRPV1's involvement in the regulation of various molecules at the systemic and aortic levels in Wistar rats treated with bacterial lipopolysaccharide (LPS) and garlic to activate the receptor. The experimental groups were as follows: 1) Control, 2) LPS, 3) Garlic, and 4) LPS + Garlic. Using Uv-visible spectrophotometry and capillary zone electrophoresis, we measured the levels of nitric oxide (NO), biopterins BH2 and BH4, total antioxidant capacity (TAC) and oxidizing capacity (OXCA). We also analyzed molecules related to vascular homeostasis such as angiotensin Ang 1-7 and Ang II, as well as endothelin ET-1. In addition, we assessed the inflammatory response by determining the levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNFα), and galectin-3 (GTN-3). For cell damage assessment, we measured levels of malondialdehyde (MDA), malonate (MTO) and 8-hydroxy-2-deoxyguanosine (8HO2dG). The results showed that LPS influenced the NO pathway at both systemic and aortic levels by increasing OXCA and reducing TAC. It also disrupted vascular homeostasis by increasing Ang-II and ET-1, while decreasing Ang1-7 levels. IL-6, TNFα, GTN-3, as well as MDA, MTO, and 8HO2dG were significantly elevated compared to the control group. The expression of iNOS was increased, but TRPV1 remained unaffected by LPS. However, garlic treatment effectively mitigated the effects of LPS and significantly increased TRPV1 expression. Furthermore, LPS caused a significant decrease in calcitonin gene-related peptide (CGRP) in the aorta, which was counteracted by garlic treatment. Overall, TRPV1 appears to play a crucial role in regulating oxidative stress and the molecules involved in damage and inflammation induced by LPS. Thus, studying TRPV1, CGRP, and allicin may offer a potential strategy for mitigating inflammatory and oxidative stress in sepsis.

Diagnostic Performance of Serum MicroRNAs for ST-Segment Elevation Myocardial Infarction in the Emergency Department.

Prompt diagnosis of ST-segment elevation myocardial infarction (STEMI) is essential for initiating timely treatment. MicroRNAs have recently emerged as biomarkers in cardiovascular diseases. This study aimed to evaluate the discriminatory capacity of serum microRNAs in identifying an ischemic origin in patients presenting with chest discomfort to the Emergency Department. The study included 98 participants (78 with STEMI and 20 with nonischemic chest discomfort). Significant differences in the expression levels of miR-133b, miR-126, and miR-155 (but not miR-1, miR-208, and miR-208b) were observed between groups. miR-133b and miR-155 exhibited 97% and 93% sensitivity in identifying STEMI patients, respectively. miR-126 demonstrated a specificity of 90% in identifying STEMI patients. No significant associations were found between microRNAs and occurrence of major adverse cardiovascular events (MACE). However, patients with MACE had higher levels of interleukin (IL)-15, IL-21, IFN-γ-induced protein-10, and N-terminal pro B-type natriuretic peptide compared to non-MACE patients. Overall, there were significant associations among the expression levels of microRNAs. However, microRNAs did not demonstrate associations with either inflammatory markers or cardiovascular risk scores. This study highlights the potential of microRNAs, particularly miR-133b and miR-126, as diagnostic biomarkers for distinguishing patients with STEMI from those presenting with nonischemic chest discomfort to the Emergency Department.

Role of the transient receptor potential vanilloid type 1 receptor and stretch-activated ion channels in nitric oxide release from endothelial cells of the aorta and heart in rats.

Shear stress stimulates nitric oxide (NO) release in endothelial cells. Stretch-activated ion channels (SACs) and the transient receptor potential vanilloid type 1 (TRPV1) receptor respond to mechanical stimulus and are permeable to Na(+), Ca(2+) and K(+). The influence of SACs and the TRPV1 receptor on NO release on the heart and on the vascular reactivity of the thoracic aorta (TA) was studied. Experiments were performed in isolated perfused heart, cultured endothelial cells and TA rings from Wistar rats. Capsaicin (10 µM, 30 µM) was used as a NO release stimulator, capsazepine (6 µM, 10 µM) was used as a capsaicin antagonist and gadolinium (3 µM, 5 µM) was used as an inhibitor of SACs. NO was measured by the Kelm and Tenorio methods. Left ventricular pressure was recorded and coronary vascular resistance was calculated. Capsaicin increased NO release in the heart by 58% (395±8 pmol/mL to 627±23 pmol/mL). Capsazepine and gadolinium inhibited NO release by 74% and 82%, respectively. This tendency was similar in all experimental models. Capsaicin attenuated the effects of norepinephrine (10 M to 7 M) on TA and had no effect in the presence of N (ω)-nitro-L-arginine methyl ester. Therefore, the authors conclude that SACs and the TRPV1 receptor are both present in the coronary endothelium and that both participate in Ca(2+)-dependent NO release.

Role of the Transient Receptor Potential Vanilloid Type 1 (TRPV1) in the Regulation of Nitric Oxide Release in Wistar Rat Aorta.

The potential transient vanilloid receptor type 1 (TRPV1) plays important functional roles in the vascular system. In the present study, we explored the role of the TRPV1 in the production of nitric oxide (NO), biopterines (BH4 and BH2), cyclic guanosine monophosphate (cGMP), malondialdehyde (MDA), phosphodiesterase-3 (PDE-3), total antioxidant capacity (TAC), and calcitonin gene-related peptide (CGRP) in the rat aorta. Wistar rats were divided into four groups: (1) control, (2) capsaicin (CS, 20 mg/kg), (3) capsazepine (CZ, 24 mg/kg), and (4) CZ + CS. Treatments were applied daily for 4 days before removing the thoracic aortas for testing of aortic tissue and endothelial cells. TRPV1 activation produced increases in BH4 14%, cGMP 25%, NO 29%, and TAC 59.2% in comparison to the controls. BH2 and MDA increased with CZ. CGRP shows a tendency to decrease with CZ. The analysis by immunocytochemistry confirmed that the TRPV1 is present in aortic endothelial cells. Aortic endothelial cells were obtained from healthy rats and cultured to directly explore the effects of CS and CZ. The activation of the TRPV1 (CS 30 µM) produced increases in BH4 17%, NO 36.6%, TAC 56.3%, and CGRP 65%, when compared to controls. BH2 decreased with CZ + CS. CS effects were diminished by CZ in cells and in the tissue. We conclude that the TRPV1 is a structure present in the membrane of aortic endothelial cells and that it participates in the production of NO. The importance of the TRPV1 should be considered in vascular reactivity studies.

The Role of the Activation of the TRPV1 Receptor and of Nitric Oxide in Changes in Endothelial and Cardiac Function and Biomarker Levels in Hypertensive Rats.

The purpose of the present study was to analyze the actions of transient receptor potential vanilloid type 1 (TRPV1) agonist capsaicin (CS) and of its antagonist capsazepine (CZ), on cardiac function as well as endothelial biomarkers and some parameters related with nitric oxide (NO) release in L-NG-nitroarginine methyl ester (L-NAME)-induced hypertensive rats. NO has been implicated in the pathophysiology of systemic arterial hypertension (SAHT). We analyzed the levels of nitric oxide (NO), tetrahydrobiopterin (BH4), malondialdehyde (MDA), total antioxidant capacity (TAC), cyclic guanosin monophosphate (cGMP), phosphodiesterase-3 (PDE-3), and the expression of endothelial nitric oxide synthase (eNOS), guanosine triphosphate cyclohydrolase 1 (GTPCH-1), protein kinase B (AKT), and TRPV1 in serum and cardiac tissue of normotensive (118±3 mmHg) and hypertensive (H) rats (165 ± 4 mmHg). Cardiac mechanical performance (CMP) was calculated and NO was quantified in the coronary effluent in the Langendorff isolated heart model. In hypertensive rats capsaicin increased the levels of NO, BH4, cGMP, and TAC, and reduced PDE-3 and MDA. Expressions of eNOS, GTPCH-1, and TRPV1 were increased, while AKT was decreased. Capsazepine diminished these effects. In the hypertensive heart, CMP improved with the CS treatment. In conclusion, the activation of TRPV1 in H rats may be an alternative mechanism for the improvement of cardiac function and systemic levels of biomarkers related to the bioavailability of NO.

[ACE gene polymorphism correlation (I/D) with the ventricular function in patients with ischemic and idiopathic dilated cardiomyopathy]. / Correlación del polimorfismo (I/D) del gen de la ECA y la función ventricular en pacientes con miocardiopatía dilatada de origen isquémico e idiopático.

UNLABELLED: Dilated cardiomyopathy is a myocardial disease, characterized by biventricular expansion. Renin-angiotensin-aldosterone system (RAAS) is closely related with the progress of this pathology. Has been shown that angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism influences as much in the plasmatic concentration as in activity of ACE. In addition, ACE IID polymorphism has been associated with remodeling phenomena and an increased risk to develop several cardiovascular diseases. On virtue of the influence of ACE gene polymorphism on RAAS, we studied the correlation between ACE I/D polymorphism with morphologic and functional clinical alterations in ischemic or idiopathic dilated cardiomyopathy in one attempt to establish its utility as prognosis factor. METHODS AND RESULTS: We studied 30 patients of The National Institute of Cardiology. Ventricular function was evaluated by transthoracic echocardiography. ACE genotype was determined by polymerase chain reaction (PCR). Results for left ventricle shown: Tei Index was increased in patients with II genotype (0.84 vs. 0.48) when were compared to patients with DD genotype p < 0.01. Eccentricity Index was lesser in the group with II genotype (0.64), than in the group DD (0.86) p < 0.01. Ventricular mass was increased in DD patients when was compared with II group (174 g vs. 133 g) Isovolumetric contraction time was shorter in group DD than in II (45 mseg vs. 139 mseg) p < 0.05. These findings denote better preservation of left ventricular function in patients with DD genotype. In opposition, right ventricle shown an increased Tei Index in the group with DD genotype (1.01) when was compared with II genotype (0.55), p < 0.05. Pulmonary artery systolic pressure tended to be higher in DD genotype group without reach statistic significance. CONCLUSIONS: In our group of study, patients with DD genotype shown better left ventricular function in ischemic or idiopathic dilated cardiomyopathy. On the opposite right ventricular function were more deteriorated in patients with ACE DD genotype.

The ACE I/D polymorphism is associated with nitric oxide metabolite and blood pressure levels in healthy Mexican men.

UNLABELLED: The I/D insertion/deletion polymorphism of the angiotensin-converting enzyme has been related to hypertension. This polymorphism also seems to have gender related implications. Angiotensin II contributes to the production and release of oxygen reactive species that react with nitric oxide, inactivating its effects. OBJECTIVE: To establish whether the ACE I/D polymorphism correlates with nitric oxide plasma metabolites in healthy men and women. METHODS: Among 896 subjects between 18 and 30 years of age range, 138 fulfilled inclusion criteria. The polymorphism was identified by polymerase chain reaction, and blood nitric oxide metabolites were analyzed following the method described by Bryan. RESULTS: Both systolic and diastolic arterial pressures were higher in men than in women (107/67 vs. 101/65 mm Hg, p<0.001). In terms of the ACE gene, there were differences in the concentration of nitric oxide metabolites in men with the I/D and D/D genotypes when compared to carriers of the I/I genotype (33.55 and 29.23 vs. 53.74 pmol/ml; p=<0.05), while there were no significant differences in women when compared by genotype. Men with the D/D genotype had higher systolic blood pressure than I/D carriers (111 vs. 104 mm Hg, p<0.05). We observed no arterial blood pressure differences in women when grouped by ACE genotype. CONCLUSIONS: The ACE D/D genotype was associated with nitric oxide metabolite levels and systolic blood pressure in clinically healthy men while it had no effect in women.

The ACE I/D polymorphism is associated with nitric oxide metabolite and blood pressure levels in healthy Mexican men / El polimorfismo I/D de la ECA se asocia con los niveles de metabolitos óxido nítrico y de presión arterial en hombres mexicanos sanos

The I/D insertion/deletion polymorphism of the angiotensin-converting enzyme has been related to hypertension. This polymorphism also seems to have gender related implications. Angiotensin II contributes to the production and release of oxygen reactive species that react with nitric oxide, inactivating its effects. Objective: To establish whether the ACE I/D polymorphism correlates with nitric oxide plasma metabolites in healthy men and women. Methods: Among 896 subjects between 18 and 30 years of age range, 138 fulfilled inclusion criteria. The polymorphism was identified by polymerase chain reaction, and blood nitric oxide metabolites were analyzed following the method described by Bryan. Results: Both systolic and diastolic arterial pressures were higher in men than in women (107/67 vs. 101/65 mmHg, p < 0.001). In terms of the ACE gene, there were differences in the concentration of nitric oxide metabolites in men with the I/D and D/D genotypes when compared to carriers of the I/I genotype (33.55 and 29.23 vs. 53.74 pmol/ml; p = <0.05), while there were no significant differences in women when compared by genotype. Men with the D/D genotype had higher systolic blood pressure than I/D carriers (111 vs. 104 mmHg, p < 0.05). We observed no arterial blood pressure differences in women when grouped by ACE genotype. Conclusions: The ACE D/D genotype was associated with nitric oxide metabolite levels and systolic blood pressure in clinically healthy men while it had no effect in women.

El polimorfismo inserción/deleción del gen de la enzima convertidora de la angiotensina (polimorfismo I/D de la ECA), se relaciona con hipertensión y sus efectos podrían estar asociados al género. La angiotensina II contribuye a la producción y liberación de especies reactivas de oxígeno, que reaccionan con el óxido nítrico (ON), inactivándolo. Objetivo: Conocer si existen diferencias en la concentración de metabolitos de ON en hombres y mujeres sanos que puedan estar influidas por el polimorfismo I/D de la ECA. Métodos: De 896 sujetos de entre 18 y 30 años, 138 cumplieron los criterios de inclusión. El polimorfismo fue identificado usando reacción en cadena de la polimerasa y los metabolitos de ON fueron analizados en sangre usando el método de Bryan. Resultados: Las presiones sistólica y diastólica fueron más elevadas en hombres que en mujeres (107/67 vs. 101/65 mmHg p < 0.001). En relación con el genotipo, existieron diferencias significativas en la concentración de metabolitos de ON en los hombres con genotipos I/D, D/D comparados con los portadores del genotipo I/I (33.55 y 29.23 vs. 53.74 pmol/ml, respectivamente; p = <0.05). No hubo diferencias significativas en las mujeres portadoras de los diferentes genotipos. Respecto a la presión arterial, los hombres con genotipo D/D presentaron mayor presión arterial sistólica que aquellos portadores de I/D (111 vs. 104 mmHg, p < 0.05). En las mujeres no se observaron diferencias significativas comparándolas por genotipo. Conclusiones: El genotipo D/D de la ECA está asociado con el nivel de metabolitos de ON en plasma y la presión arterial sistólica en hombres clínicamente sanos; esta asociación no se observa en las mujeres.

Correlación del polimorfismo (I/D) del gen de la ECA y la función ventricular en pacientes con miocardiopatía dilatada de origen isquémico e idiopático / ACE gene polymorphysm correlation (I/D) with the ventricular function in patients with ischemic and dilate idiopathic cardiomyopathy

Dilated cardiomyopathy is a myocardial disease, characterized by biventricular expansion. Renin-angiotensin-aldosterone system (RAAS) is closely related with the progress of this pathology. Has been shown that angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism influences as much in the plasmatic concentration as in activity of ACE. In addition, ACE I/D polymorphism has been associated with remodeling phenomena and an increased risk to develop several cardiovascular diseases. On virtue of the influence of ACE gene polymorphism on RAAS, we studied the correlation between ACE I/D polymorphism with morphologic and functional clinical alterations in ischemic or idiopathic dilated cardiomyopathy in one attempt to establish its utility as prognosis factor. Methods and results. We studied 30 patients of The National Institute of Cardiology. Ventricular function was evaluated by transthoracic echocardiography. ACE genotype was determined by polymerase chain reaction (PCR). Results for left ventricle shown: Tei Index was increased in patients with II genotype (0.84 vs. 0.48) when were compared to patients with DD genotype p < 0.01. Eccentricity Index was lesser in the group with II genotype (0.64), than in the group DD (0.86) p < 0.01. Ventricular mass was increased in DD patients when was compared with II group (174 g vs. 133 g) Isovolumetric contraction time was shorter in group DD than in II (45 mseg vs. 139 mseg) p < O.OB. These findings denote better preservation of left ventricular function in patients with DD genotype. In opposition, right ventricle shown an increased Tei Index in the group with DD genotype (1.01) when was compared with II genotype (0.55), p < 0.05. Pulmonary artery systolic pressure tended to be higher in DD genotype group without reach statistic significance. Conclusions. In our group of study, patients with DD genotype shown better left ventricular function in ischemia or idiopathic dilated cardiomyopathy. On the opposite right ventricular function were more deteriorated in patients with ACE DD genotype.

La miocardiopatía dilatada es una enfermedad primaria del miocardio, caracterizada por dilatación biventricular. El sistema renina-angiotensina-aldosterona (SRAA) está estrechamente relacionado con el progreso de esta patología. Se ha demostrado que el polimorfismo inserción/deleción (I/D) del gen de la enzima convertidora de angiotensina (ECA) influye en la concentración plasmática y la actividad de esta enzima, además este polimorfismo se ha asociado con fenómenos de remodelación e incremento en el riesgo de padecer diferentes enfermedades cardiovasculares. En virtud de la influencia de las variantes polimórficas del gen de la ECA sobre la respuesta del SRAA, en el presente trabajo se estudió la posible correlación del polimorfismo I/D del gen de la ECA con las alteraciones clínicas morfológicas y funcionales de la cardiomiopatía dilatada tanto de origen isquémico como de origen idiopático con el fin de establecer su posible utilidad como factor pronóstico. Métodos y resultados. El estudio incluyó a 30 pacientes seleccionados de la consulta externa del Instituto Nacional de Cardiología <>, la función ventricular se valoró mediante ecocardiografía transtorácica. El genotipo de la ECA se determinó por reacción en cadena de la polimerasa (PCR). Resultados para el ventrículo izquierdo: El índice de Tei se observó visiblemente incrementado en los pacientes con genotipo II 0.84 vs. 0.48 de los pacientes con genotipo DD p < 0.01. El índice de excentricidad fue menor en los casos con genotipo II: 0.64, comparado con aquellos con genotipo DD: 0.86 p < 0.01. La masa ventricular tendió a ser mayor en el grupo DD en relación con el II (174 g vs. 133 g). El tiempo de contracción isovolumétrica fue menor en el grupo DD en comparación al II (45 mseg vs. 139 mseg) p < 0.05, estos hallazgos denotan una mejor preservación de la función ventricular izquierda en los pacientes con genotipo DD. Por otra parte, el ventrículo derecho mostró un comportamiento distinto al observado para el ventrículo izquierdo, pues el índice de Tei fue mayor para los pacientes con el genotipo DD (1.01) comparado con el grupo del genotipo II (0.55), p < 0.05. La presión sistólica de la arteria pulmonar tendió a ser mayor en los pacientes con genotipo DD sin alcanzar una significancia estadística. Conclusión. El genotipo DD se asocia con una mejor función ventricular izquierda en los pacientes con miocardiopatía dilatada de origen tanto isquémico como idiopático; por el contrario, la función ventricular derecha de los pacientes con genotipo DD muestra una mayor alteración en el índice de Tei en esta patología.