Oxidative damage to cells is thought to be a causative factor in disease and aging. Aside from trauma, the process of death, at the cell level, is oxidation. The death of cells is caused by an invading molecule called a “free radical” which invades cells causing their death. These invading free radicals are part of our environment, that puff of cigarette smoke, the chemical preservatives in our foods, and water, anything that is foreign to the body can, potentially, become a free radical. Free radicals skin production is part of our body free radicals generation whenever immune- system becomes active for example during infections or inflammatory disorders such as inflammatory acne vulgaris, which may lead to follicular epithelium damage and disruption. However, in roundworms (Caenorhabditis elegans), blocking the production of the naturally occurring antioxidant superoxide dismutase has recently been shown to increase lifespan [1].
These are atoms or molecules with an unpaired electron. A molecule is stable and harmless when the electrons are in pairs. If single, they are unstable and can potentially do damage. When an electron is taken from another molecule it becomes unstable and the attacking molecule becomes stable. This process damages various cell structures.
Free radicals are naturally occurring and an important part of biological functions such as immunity, inflammation, growth and repair and implicate processes such as aging or diseases such as hair loss, acne and photoaging. While UVA and UVB implicate in photoaging due to expression of matrix metaloproteinases, MMP-1, and increased interluekin-1-α production which leads to destructive effect of neprilysin on dermal collagen and elastin fibers, free radical insult is another expedient in the skin aging. Free radicals can have negative effects when they damage proteins, lipids and nucleic acids. They are normally held in balance in biological systems by antioxidant defense mechanisms. Environmental insults, infections, smoking, radiation and sunlight can also cause the formation of free radicals.
UVA and UVB in photoaging due to free radical generation
Free radicals also increase production of vital hormones or chemical messengers like prostaglandins and cytokines disturbing hormonal balance and invoking inflammatory cascades, two axes whose insulting merger culminate in acne vulgaris by altering amount and composition of skin surface lipids and sebum output. It can be seen that we need free radicals to maintain health. It is these free radicals skin overproduction that is a problem. Results have demonstrated that the overexpression of catalase, an enzyme involved in the decomposition of hydrogen peroxide, increased both the average lifespan and maximum lifespan of mice by 20% [2].
The skin exposed to an air pollutant: top left) unexposed normal skin, top right) an increase in the skin mitochondria, bottom left) an increase in endoplasmic reticulum, bottom right) autophagosomes are seen.
Simplistically, when a free radical skin penetration occurs, the body and the immune system do not function optimally, different things may occur: