Image by JS F16
As you have already read, following an irritation or injury the enzyme phospholipase A2 (PLA2) will extract arachidonic acid from the plasma membrane to begin the process of making inflammatory mediators. After cleavage from the phospholipid membrane, arachidonic acid can be folded and manipulated. Arachidonic acid can then be chemically altered to become a variety of prostaglandins and leukotrienes. Together, we call these two groups of molecules made from arachidonic acid “eicosanoids.”
Drugs called corticosteroids inhibit PLA2 and can thus block the production of the eicosanoids (prostaglandins and leukotrienes). Corticosteroids are helpful to treat people with asthma because they stop bronchoconstriction that results in leukotriene production. Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen inhibit the COX enzyme and thus prevent the production of prostaglandins and other mediators on the left of the above figure. NSAIDs are better for general pain and would not be successful in the treatment of asthma because they do not block leukotriene production.
Remember how TNF-α plays a pivotal part in the inflammatory response and movement of white blood cells into tissue? Monoclonal antibodies that target the pro-inflammatory actions of TNF-α are used to reduce inflammation seen in rheumatoid arthritis and Crohn's disease. Remicade and Humira are two examples of this type of medication.
You may have heard people talking about omega-3 and omega-6 fatty acids having anti-inflammatory or inflammatory properties. Recently, there has been a lot of interest and research into dietary modification of the inflammatory response. Omega-3 polyunsaturated fatty acids are considered to be antithrombotic and anti-inflammatory. It appears that these types of fatty acids are shunted to form prostaglandins and leukotrienes that are less inflammatory in nature. Foods that are rich in Omega-3 include fish, flax seed, chia seeds and leafy greens. On the other hand, Omega-6 polyunsaturated fatty acids are shunted to become eicosanoids that are more prothrombotic and pro-inflammatory. Foods high in omega-6 fatty acids are soybeans, corn, safflower and sunflower oils, nuts, seeds, meat, poultry, fish, and eggs.