Acute inflammation is essential to health—and, so too, is its resolution. Pathologists divide acute inflammation into 2 parts:
When microbes invade the body by barrier break, tissue injury or trauma, they set into motion a cascade of events. The first part of this cascade is the initiation phase, also known as the acute inflammatory response, and as Dr. Serhan notes, “is actually protective of the host organism” because it signals the need for the second part or resolution phase of the invasion. However, if the inflammation process runs uncontrolled, or the body fails to limit it, it becomes excessive. This is the basis of many chronic illnesses which include the metabolic syndrome, various neurologic and vascular diseases. Dr. Serhan’s publication discusses data about innate cellular mediators with a ‘pro-resolving’ capacity—or the ability to actively reduce acute inflammation—and how some of these mediators can be synthesized from the omega-3 essential fatty acids (EPA and DHA) found in fish oils. These “Specialized Pro-resolving Mediators” (SPMs) are classified as Lipoxins, Resolvins, Protectins and Maresins. Each SPM has its own pathway which can be identified by liquid chromatography in the lab.
At cellular and molecular levels, in animal models and human cells, SPMs work by:
- Counterregulating pro-inflammatory mediators (eicosanoids, chemokines, cytokines and adipokines)
- Regulating specific cellular traffic
- Enhancing destruction of microbes
At this time, identifying SPMs in human tissues requires the use of specialized techniques and have been found in blood (plasma and serum components) and human breast milk. Dr. Serhan postulates, based on the pre-clinical disease models discussed in this publication, potential treatment of inflammatory diseases may be achieved with SPMs to stimulate targeted resolution of the inflammation and, at the same time, protect other organs from collateral damage. He notes that this may be accomplished through clinical trials to determine the functional importance of SPMs in humans.