The Inflammation Cycle and Your Skin
Your body is designed to recognize and defend itself against bacteria, viruses, and other substances that it believes to be foreign and/or harmful. Your skin is typically the first line of defense in that quest. So exactly how does that work and what does it mean for your healthy complexion.
What Is Inflammation and How Does It Work?While it's generally associated with unpleasantness, inflammation in its truest form is actually a vital part of our defense system and the body's response to tissue injury, irritation, or other harmful conditions, such as infection. It is actually essential for tissue recovery. The immune response to acute (sudden) inflammation helps tissue to repair or adapt over the short term. When inflammation becomes chronic (long-term or recurring), it can result in effects that actually lead to tissue degeneration. Antigens are substances on the surface of cells (like bacteria or poison ivy 'venom') and non-living things (like splinters and chemicals) that are recognized by the body as possibly harmful. They essentially label anything that could be considered "foreign" (shouldn't be there). The immune system will then try to destroy any of these substances. When tissues are injured by something like trauma or heat, or invaded by things like viruses and bacteria, the response that follows is what you know as inflammation. Injured or damaged cells release chemicals like histamine, bradykinin, and prostaglandins. These chemicals make the walls of the blood tissue around the injury more permeable to liquid, so fluid leaks out of the blood vessels and into the tissue surrounding the injury. This is what causes the swelling. The fluid helps to protect the rest of the body by surrounding and isolating the foreign substance from having contact with the rest of the body. The histamine, bradykinin, and prostaglandins will also attract certain kinds of white blood cells called phagocytes. These cells will actually "eat" any germs as well as any damaged or dead cells. This process is called phagocytosis. Following the immune response, damaged cells that are still functioning enough to proliferate will regenerate. Epithelial cells are pretty good at this. Some cells aren't able to do this at all. The ability to regenerate is dependent upon how complicated the tissue is in the first place. Skin is nice and flat, so it's easy to rebuild. Glands, on the other hand, are much more intricate and difficult. If the tissue damage is great enough that it can't regenerate,it will repair. You know reparation is happening by the formation of scar tissue. Cells will create new blood vessels, and others (fibroblasts) will create a loose framework of connective tissue (granulation tissue). New blood vessels will create circulation to the healing area, and fibroblasts will produce collagen. Collagen is what gives tissue its strength. When enough collagen is built up and packed densely together, a scar results.
Immune System DisordersSometimes the immune system goes a little haywire. It can become over-reactive or give the wrong response. This leads to complications like allergies, hypersensitivity, autoimmune disorders, immunodeficiency disorders, and others. Tissue destruction can occur when the regulatory mechanisms of the inflammatory response are defective, or the ability to clear damaged tissue and foreign substances is impaired. Autoimmune reactions trigger chronic inflammation because the body is launching an immune response against its own tissues.
What Does Chronic Inflammation Look Like?
Inflammation is remembered by the body by way of cells within our immune system, to help trigger a better defense, the next time that invader comes around. Those memories can be used to help us heal faster the next time. Research is now showing that our skin has the same ability to remember an inflammatory response, too. "By enhancing responsiveness to inflammation, these memories help the skin maintain its integrity, a feature that is beneficial in healing wounds after an injury,"says Elaine Fuchs, a member of a research team studying this process at Rockefeller University in New York. "This memory may also have detrimental effects, however, such as contributing to the relapse of certain inflammatory disorders such as psoriasis." Psoriasis and other skin disorders can repeatedly flare up in the same spot. Results of Fuchs' team's research suggest that the skin, itself, could be contributing to these recurring reactions. To put it another way, the inflammation puts cells on high alert - and to some extent they then stay that way. This process isn't fully understood, but essentially, the skin's natural immune defense mode becomes locked in a repetitive cycle: the inflammatory response cycle. When the skin is exposed to things like environmental free radicals or antigens, the immune response is triggered. This causes inflammation, repair, and ultimately results in oxidative damage. This leads to a release of certain types of cells designed to combat the damage (pro-inflammatory cytokines), which leads to more tissue damage and the associated immune response, and so on. . . .and so on. . . It is currently believed that inflammaging (chronic inflammation) is a consequence of a cumulative lifetime exposure to certain stimulants. These stimulants include sunlight, pollution, smoking, chemicals, detergents, and cosmetic products. The resulting inflammatory response cycle causes tissue injury and healing to happen simultaneously. The resultant cellular and molecular damage, while not clinically evident, slowly accumulates over the years.
Skin Aging and Inflammation
Cytokines actually inhibit the production of collagen. Not only that, but they also work to break down existing collagen. This affects the skin's overall appearance and resilience, and wrinkles show up.