Video Experimental Relacionado

Updated: Jul 13, 2026

Non-invasive Assessment of Microvascular and Endothelial Function

Non-invasive Assessment of Microvascular and Endothelial Function

Published on: January 29, 2013

Diferencias raciales específicas en la función endotelial: predisposición de los afroamericanos a las enfermedades

Leszek Kalinowski¹, Iwona T Dobrucki, Tadeusz Malinski

¹Department of Biochemistry, Ohio University, Athens, OH 45701, USA.

|May 26, 2004

Resumen

Las células endoteliales de individuos negros muestran reducción de óxido nítrico (NO) y aumento de superóxido (O2-) y peroxinitrito (ONOO-), lo que contribuye a la disfunción vascular y el riesgo de enfermedades cardiovasculares en comparación con los individuos blancos.

Área de la Ciencia:

Biología Vascular Biología Vascular
La bioquímica es la bioquímica.
Fisiología Celular Fisiología celular

Sus antecedentes:

Las complicaciones de la hipertensión y la diabetes mellitus son más graves en las poblaciones negras que en las blancas.
La interacción entre el superóxido (O2-) y el óxido nítrico (NO), formando peroxinitrito (ONOO-), es clave en la fisiopatología vascular.
Las disparidades raciales en el metabolismo endotelial NO/O2-/ONOO- pueden predisponer a las personas negras a la disfunción endotelial.

Objetivo del estudio:

Investigar las diferencias raciales en el metabolismo endotelial de óxido nítrico (NO), superóxido (O2) y peroxinitrito (ONOO).
Determinar los mecanismos subyacentes que contribuyen a la disfunción endotelial en personas negras.

Principales métodos:

Se utilizaron nanosensores electroquímicos de alta sensibilidad para medir la liberación de NO/O2-/ONOO en las células endotelial de la vena umbilical humana (HUVEC) de donantes negros y blancos.
Se analizó la actividad y expresión de la NAD(P) H-oxidasa y la NO sintetasa endotelial (eNOS) a través de ensayos de enzima y inmunoblotación occidentales.

Principales resultados:

Los HUVEC de individuos negros exhibieron una reducción de la liberación de NO bioactivo y un aumento de la liberación de O2 y ONOO en comparación con los de individuos blancos.
El aumento de la expresión de eNOS en HUVEC de individuos negros se asoció con una disminución de la biodisponibilidad de NO debido a una mayor degradación de NO por O2-.
El aumento de la producción de O2, principalmente de la NAD(P) H-oxidasa y la eNOS no acoplada, contribuye al aumento del estrés oxidativo.

Conclusiones:

El equilibrio NO/O2-/ONOO- en las células endoteliales de los individuos negros se desplaza hacia estados redox asociados con la disfunción endotelial.
Estas alteraciones metabólicas pueden explicar la predisposición racial a la disfunción endotelial y las complicaciones cardiovasculares.
La mejora de la inactivación de NO por el estrés oxidativo es un sello distintivo de la disfunción endotelial en individuos negros.

Más Videos Relacionados

Assessment of Vascular Function in Patients With Chronic Kidney Disease

Assessment of Vascular Function in Patients With Chronic Kidney Disease

Published on: June 16, 2014

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research

Published on: October 22, 2014

Videos de Conceptos Relacionados

Stereotypes, Prejudice, and Discrimination

Stereotypes, Prejudice, and Discrimination

Humans are very diverse and although we share many similarities, we also have many differences. The social groups we belong to help form our identities (Tajfel, 1974). These differences may be difficult for some people to reconcile, which may lead to prejudice toward people who are different. Prejudice is a negative attitude and feeling toward an individual based solely on one’s membership in a particular social group (Allport, 1954; Brown, 2010). Prejudice is common against people who are...

Regulation of Angiogenesis and Blood Supply

Regulation of Angiogenesis and Blood Supply

Rapidly dividing tumors, embryos, and wounded tissues require more oxygen than usual, lowering the oxygen concentration in the blood. At low oxygen or hypoxic conditions, an oxygen-sensitive transcription factor called the hypoxia-inducible factor 1 or HIF1 is activated. HIF1 is a dimeric protein of alpha (ɑ) and beta (β) subunits. Under optimal oxygen conditions, HIF1β is present in the nucleus while HIF1ɑ remains in the cytosol. HIF1ɑ is hydroxylated by prolyl hydroxylase and factor...

Principles of Pharmacogenetics: Types of Genetic Variants

Principles of Pharmacogenetics: Types of Genetic Variants

The human genome is over 99.9% identical between individuals, yet genetic differences exist at millions of bases. The human genome contains approximately 3 million variant positions per individual, many of which are heterozygous, contributing to genetic diversity and individual traits. Genetic variations include single-nucleotide polymorphisms (SNPs), insertions, deletions, and copy number variations (CNVs).SNPs, the most common variation, involve single-base changes in DNA. These can be...

Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu

Pharmacogenetic Phenotypes: Alterations in Pharmacokinetics, Drug Targets and Biologic Milieu

Genetic variations significantly influence drug response through pharmacokinetics, receptor interactions, and biologic milieu modifications. Pharmacokinetic alterations impact drug metabolism and clearance, affecting efficacy and toxicity. Variants in drug-metabolizing enzymes, such as CYP2C9 and CYP2C19, alter drug activation and elimination. For example, CYP2C9 loss-of-function variants require lower warfarin doses to prevent excessive bleeding, while CYP2C19 variants reduce clopidogrel...

Coronary Artery Disease I: Introduction

Coronary Artery Disease I: Introduction

Coronary Artery Disease (CAD): An Overview with Scientific InsightsCoronary Artery Disease (CAD), often referred to as C-A-D, is a prevalent blood vessel disorder classified under the broader category of atherosclerosis. Atherosclerosis is a pathological process characterized by the hardening and narrowing of arteries due to the accumulation of atherosclerotic plaques. These plaques are composed of cholesterol, fatty substances, inflammatory cells, calcium, and fibrin, reducing blood flow to...

Peripheral Artery Disease I: Introduction

Peripheral Artery Disease I: Introduction

Peripheral artery disease (PAD) predominantly results from atherosclerosis, which involves the accumulation of fatty deposits, or plaques, within the walls of arteries. This causes them to narrow and harden, significantly reducing blood flow. PAD predominantly affects the legs, particularly the arteries supplying the thighs and calves. In rare cases, it may involve other arteries, including those in the arms.Etiology of PAD:The principal cause of PAD is atherosclerosis, which results from fatty...