Inflammation is complex protective and healing response by vascular tissues. The heat and extra blood flow from inflammation accelerate healing.
Wounds and infections would never heal without inflammation. Inflammation is initiated by chemical agents present in all tissues, in concert with resident phagocytes. In healthy animals, acute inflammation is a tuned response: regulated by cell-derived mediators, biochemical cascade systems, and complemented by commensal bacteria.
By contrast, chronic inflammation is a slow-burning fire, which sets in when healing cannot be completed, leading to a progressive shift in the type of cells at the inflamed site. Chronic inflammation is characterized by continued, but increasingly feeble attempts at healing, along with the destruction of formerly functional tissues.
Chronic inflammation is the result of an imbalanced immune system. The intricately interdependent immune system is amazingly robust, but can be worn down by poor lifestyle choices, and create dynamics which self-perpetuate and cascade into disease.
While mast cells in healthy individuals help heal damaged tissue, they accumulate in the fat tissue of the obese, where the mast cells dysfunction and leak molecular garbage into surrounding tissue.
From a diagnostic viewpoint, inflammation, whether acute or chronic, is a symptom of attempted healing by the body.
Many nonphagocytic cells have means to kill potential invaders. The gas nitric oxide (NO) can be formed by many cells in the body. NO serves as a key biological messenger in vertebrate, but it also acts against microbes that invade the liquid inside cells (cytosol).
Sustained levels of increased NO production damage tissue and contribute to vascular collapse. Chronically high NO is associated with a various carcinomas and inflammatory maladies, such as juvenile diabetes, arthritis, and multiple sclerosis. Carcinoma is a malignant tumor, typically arising from transformed epithelial cells.