Related Experiment Video

Updated: Jul 14, 2026

Alternative Methods for the Detection of Superoxide Anion Generation in Platelets
06:35

Alternative Methods for the Detection of Superoxide Anion Generation in Platelets

Published on: March 29, 2024

No evidence for prooxidative effects of homocysteine in vascular endothelial cells

Juergen Frank1, Susanne C Beck, Andrea Flaccus

  • 1zet Life Science Laboratory Linz, Centre for Alternative and Complementary Methods to Animal Testing, Scharitzerstrassse 6-8, 4020, Linz, Austria. j.frank@zet.or.at

European Journal of Nutrition
|June 30, 2007
PubMed

Insights

Homocysteine (HCys) did not directly cause oxidative stress or cell damage in endothelial cells. While HCys moderately increased monocyte adhesion, this effect was non-specific and not linked to increased reactive oxygen species.

Area of Science:

  • Cardiovascular Biology
  • Endothelial Cell Biology
  • Oxidative Stress Research

Background:

  • Epidemiological studies suggest homocysteine (HCys) involvement in cardiovascular disease (CVD).
  • In vitro studies indicate HCys may promote atherogenesis through oxidant stress, inflammation, and endothelial dysfunction.
  • The specific mechanisms by which HCys affects endothelial cells and monocyte interactions remain under investigation.

Purpose of the Study:

  • To investigate the prooxidative and cytotoxic effects of HCys on endothelial cells in vitro.
  • To examine HCys-induced monocyte adhesion to endothelial cells and its impact on reactive oxygen species (ROS) production.
  • To determine if observed effects are specific to HCys or non-specific.

Main Methods:

  • Exposure of human microvascular endothelial cells (HMEC-1) to varying concentrations of HCys (0-250 microM).
  • Assessment of monocyte (Mono Mac 6) adhesion to HCys-treated endothelial cell monolayers.
  • Measurement of reactive oxygen species (ROS) production in endothelial cells and monocytes.
  • Analysis of VCAM and ICAM-1 mRNA expression.
  • Comparison with effects of cysteine and glutathione.

Main Results:

  • HCys exhibited no prooxidative or cytotoxic effects on endothelial cells.
  • A moderate, time- and concentration-dependent increase in monocyte adhesion (up to 28.3%) was observed with HCys exposure.
  • This increase in adhesion correlated with elevated VCAM and ICAM-1 mRNA expression.
  • Similar increases in monocyte adhesion were noted with cysteine and glutathione, suggesting a non-specific effect.
  • Adherent monocytes did not augment ROS formation in either cell type.

Conclusions:

  • HCys does not appear to directly induce oxidative stress or cytotoxicity in endothelial cells.
  • The observed moderate increase in monocyte adhesion is likely a non-specific effect, not mediated by HCys-specific prooxidative mechanisms.
  • These findings challenge the direct pro-inflammatory and pro-oxidative role of HCys in endothelial dysfunction and atherogenesis in vitro.

More Related Videos

En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries08:58

En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries

Published on: February 25, 2016

Assessing Endothelial Vasodilator Function with the Endo-PAT 200007:46

Assessing Endothelial Vasodilator Function with the Endo-PAT 2000

Published on: October 15, 2010

Related Concept Videos

Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers01:19

Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers

Cardiac biomarkers are critical in diagnosing, prognosing, and managing cardiovascular diseases. Routine measurement of specific biomarkers such as B-type natriuretic peptide (BNP), C-reactive protein (CRP), and homocysteine (Hcy) is common practice in clinical settings to evaluate heart function and predict cardiovascular events.
These markers indicate stress or strain on the heart muscle:
Natriuretic Peptides (BNP)
Cardiac myocytes produce these hormones in response to ventricular stretching...
Peroxisomes01:24

Peroxisomes

Peroxisomes are specialized organelles present in fungi, plant, and animal cells. It can vary in number, size, morphology, and activity depending on the type of tissue and the nutritional state of the cell. For example, cells with active lipid metabolism, such as adipocytes, neurons, and hepatocytes, have more peroxisomes than other cells in the body. Besides their primary role in breaking down complex organic molecules, peroxisomes can also synthesize specific macromolecules and participate in...
Effects of EDTA on End-Point Detection Methods01:18

Effects of EDTA on End-Point Detection Methods

Different methods, such as visual observance of metal-ion indicators, spectroscopic techniques, and potentiometric methods, can determine the endpoint of an EDTA titration.
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...
Oxidation of Phenols to Quinones01:17

Oxidation of Phenols to Quinones

In the presence of oxidizing agents, phenols are oxidized to quinones. Quinones can be easily reduced back to phenols using mild reducing agents. The electron-donating hydroxyl group enhances the reactivity of the aromatic ring, enabling oxidation of the ring even in the absence of an α hydrogen.
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox property is crucial in...