LIPOXYDATION OF MEMBRANE LIPIDS: How the Cell’s Membrane Fats Betray the Cells?
Oxidative stress and free radicals are the words we often use when talking about cellular dysfunction and diseases.
However, few people realize that these harmful molecules can oxidize the fats that form cell membranes.
The phenomenon is known as lipid peroxidation and plays a critical role in cell biology.
What is lipid peroxidation?
Lipids are the main component of cell membranes and comprise polyunsaturated fatty acids (PUFAs). Excessive amounts of reactive oxygen species (ROS) may attack these PUFAs and result in the oxidation of lipids. It resembles the effect of a single spark causing a fire. One damaged lipid may lead to oxidation of many lipids.
Excessive lipid peroxidation may:
- Lead to membrane damage
→ Change its structure and functions - Affect cellular signaling
→ Interfere with vital cellular functions - Cause indirect damage to proteins and DNA
→ Reactive compounds produced in the course of lipid oxidation may react with other cells’ molecules. - Cause tissue damage
→ Excessive oxidative damage has been linked to various pathological conditions - Affect inflammation
→ Products of lipid oxidation may be involved in inflammatory signaling.
However, there is something even more interesting…
Lipid peroxidation is not always bad…
Sometimes it might participate in some regulated cell death processes.
- The most popular example is ferroptosis — an iron-dependent regulated cell death, which is accompanied by the formation of lipid hydroperoxides.
- The study of lipid peroxidation in this context has been widely used for cancer research since regulating lipid metabolism and antioxidant defense is a promising way to treat cancer.
Then, how does our organism defend itself against lipid peroxidation?
Our cells have systems of antioxidant defense, which include such components as:
Glutathione
Glutathione peroxidases
Vitamin E
Superoxide dismutase
Catalase
Lipid peroxidation is not only “fat oxidation”.
In this process, there is a fine balance between oxidative stress, cell defense, signaling, and cell death.
The understanding of this balance might be crucial in terms of future cancer therapy, studies on neurodegenerative diseases, and pharmaceutical development.
Sometimes, the difference between survival and cell death depends on the lipid metabolism of a cell.
What do you think – is the regulation of lipid peroxidation going to be a new way to combat cancer?
MBH/PS