Related Experiment Video
Updated: May 28, 2026
06:32
A Thermoplasmonic Approach for Investigating Plasma Membrane Repair in Living Cells and Model Membranes
Published on: January 19, 2024
The plasma membrane is involved in the visible light-tissue interaction
Ronit Lavi1, Rinat Ankri, Michael Sinyakov
1Department of Chemistry, Bar-Ilan University, Ramat-Gan, Israel.
Photomedicine and Laser Surgery
|October 5, 2011
Summary
Visible light, particularly blue light, increases reactive oxygen species (ROS) in sperm plasma membranes. This ROS production stems from a photochemical reaction, not an enzyme-catalyzed process, highlighting a novel light-tissue interaction.
Area of Science:
- Biophysics
- Cell Biology
- Photochemistry
Background:
- Photobiostimulation may involve light-induced reactive oxygen species (ROS) acting as signal messengers.
- Mitochondrial cytochromes were previously implicated as primary targets for visible light absorption.
- ROS production following visible light exposure has been confirmed using EPR spin-trapping.
Purpose of the Study:
- To investigate the plasma membrane's role in light-tissue interactions.
- To explore the involvement of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase electron chain as a photosensitizer.
- To determine the mechanism of light-induced ROS production in sperm membranes.
Main Methods:
- Isolated sperm membranes were exposed to visible light (400-800 nm) at varying intensities.
- Oxygen radical production was quantified using electron paramagnetic resonance (EPR) spin-trapping with DMPO.
- Denatured membranes were irradiated to differentiate between enzyme-catalyzed and photochemical reactions.
Main Results:
- Visible light exposure significantly increased oxyradical levels in isolated sperm membranes.
- Blue light was more effective in inducing ROS production compared to red light.
- Denatured and non-denatured membranes exhibited similar ROS production levels upon illumination.
Conclusions:
- Visible light, especially blue light, elevates ROS levels in isolated plasma membranes.
- The primary mechanism for ROS formation appears to be a photochemical reaction involving membrane chromophores (e.g., cytochromes, flavins) and oxygen.
- Enzyme-catalyzed photochemical reactions are unlikely to be the main driver of light-induced ROS in this context.
Related Concept Videos
01:24What are Membranes?
A cell's plasma membrane demarcates the cell's borders and determines the nature of its interaction with the environment. Cells exclude certain substances, take in others, and excrete some others in controlled quantities. The plasma membrane must be flexible to allow certain cells, such as red and white blood cells, to change their shape while passing through narrow capillaries. These are the more obvious plasma membrane functions. In addition, the plasma membrane's surface carries markers that...
01:22Photoreceptors and Visual Pathways
At the molecular level, visual signals trigger transformations in photopigment molecules, resulting in changes in the photoreceptor cell's membrane potential. The photon's energy level is denoted by its wavelength, with each specific wavelength of visible light associated with a distinct color. The spectral range of visible light, classified as electromagnetic radiation, spans from 380 to 720 nm. Electromagnetic radiation wavelengths exceeding 720 nm fall under the infrared category, whereas...
01:22Enlargement of the Plasma Membrane
Cell division and enlargement are processes that require precise control. The control ensures that cell division cannot proceed unless the cell has grown to a specific size. A spherical, dividing cell requires an approximately 1.6X increase in its surface area to double its volume. The secretory pathway also has a significant role in cell membrane enlargement. Secretory vesicles that bud off from the Golgi apparatus and later fuse with the plasma membrane during exocytosis are a major source of...
01:16Energy Transfer in Chemical Reactions
Chemical reactions require sufficient energy to cause the matter to collide with enough precision and force that old chemical bonds can be broken and new ones formed. In general, kinetic energy is the form of energy powering any type of matter in motion. Imagine a person building a brick wall. The energy it takes to lift and place one brick on top of another is the kinetic energy—the energy matter possesses because of its motion. Once the wall is in place, it stores potential energy. Potential...
02:00Photoreceptors and Plant Responses to Light
Light plays a significant role in regulating the growth and development of plants. In addition to providing energy for photosynthesis, light provides other important cues to regulate a range of developmental and physiological responses in plants.
01:27Tissue Membranes
A tissue membrane is a thin layer of cells that covers the outside of the body, the organs, internal passageways that lead to the exterior of the body, and the lining of the moveable joint cavities. There are two basic types of tissue membranes— connective tissue and epithelial membranes.
Connective Tissue Membranes
The connective tissue membrane is formed solely from connective tissue. These membranes encapsulate organs, such as the kidneys, and line our movable joints. A synovial membrane is...
Connective Tissue Membranes
The connective tissue membrane is formed solely from connective tissue. These membranes encapsulate organs, such as the kidneys, and line our movable joints. A synovial membrane is...