Vascular Dysfunction
Conditions
Keywords
Photobiomodulation, Light-emitting diode, Vascular function, Radial artery
Brief summary
LED photobiomodulation therapy (PBMT) is widely recognized for its beneficial effects in several clinical conditions; however, its potential in modulating vascular function is not yet fully established. Objective: This study aimed to evaluate the application of PBMT by LED (light-emittion diode) using a combined red and near-infrared light spectrum, with a focus on improving the vascular function of the radial artery in vitro. Methodology: A total of 30 radial artery segments were studied and divided into three groups of 10 segments: the PBMT LED group combined with red and infrared light (R + IR), the red light (R) group, and the infrared light (IR) group. Prior to light irradiation at wavelengths of 650 nm and 940 nm, vascular function in these segments was pharmacologically inhibited using L-NAME. The drugs phenylephrine, acetylcholine, and sodium nitroprusside were used to determine if irradiation could restore the inhibited vascular functions. Superoxide anion levels, an important reactive oxygen specie (ROS), were measured using a chemiluminescence assay with lucigenin. The bioavailability of nitric oxide was evaluated using a Griess Reagent Kit assay, while nitric oxide production was assessed through the DAF fluorescence assay. The vascular inflammation was determined by the Intercellular Adhesion Molecule 1 (ICAM-1) expression.
Interventions
DEVICELight-emitting diode photobiomodulation therapy
For the intervention, the isolated arteries were assigned to three experimental groups. The first group (red) was exposed to light at a wavelength of 650 nm for 83 seconds. The second group (infrared) received irradiation at 940 nm for 94 seconds. The third group (mixed) was irradiated with a combination of red (650 nm) and infrared (940 nm) light for 73 seconds.
Sponsors
University of Sao Paulo
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
NONE
Intervention model description
To irradiate the arteries, we used a 14 cm × 14 cm LED blanket composed of 30 red-spectrum LEDs (wavelength: 650 nm), delivering a power density of 1.9 mW/cm² and an energy density of 1.7 J/cm² over an irradiation period of 83 seconds. A separate 14 cm × 14 cm infrared LED blanket, also containing 30 LEDs (wavelength: 940 nm), delivered a power density of 1.7 mW/cm² and an energy density of 1.7 J/cm² with an irradiation time of 94 seconds. Additionally, a 14 cm × 14 cm mixed LED blanket, consisting of 18 red (650 nm) and 18 infrared (940 nm) LEDs, provided a power density of 1.7 mW/cm² and an energy density of 0.16 J/cm² over an irradiation period of 73 seconds.
Eligibility
Sex/Gender
ALL
Age
20 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Patients undergoing coronary artery bypass grafting using the radial artery
Exclusion criteria
* Patients with poorly compliant radial arteries or those who underwent coronary artery bypass grafting without use of the radial artery were excluded from the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Diameter of Isolated Radial Artery Rings (2 mm) | 12 months | Description of Primary Outcome Measure(s): The primary outcome of this study is the evaluation of vascular compliance during vasodilation of isolated radial artery rings (2 mm in diameter), with a specific focus on the effects of LED photobiomodulation on arterial function. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Evaluation of reactive oxygen species (ROS) | 12 months | Superoxide anion (O₂--) generation, a key reactive oxygen species (ROS), will be measured in arterial tissue from the R + IR, R, and IR groups using a lucigenin-enhanced chemiluminescence assay. Lucigenin will serve as the electron acceptor, and nicotinamide adenine dinucleotide phosphate (NADPH) as the substrate. Results will be expressed as a percentage of concentration. |
Countries
Brazil
Outcome results
None listed