ABSTRACT
Inammation is a normal but complex biological protective response induced by tissue injury or infection. It is a highly regulated rst-line defense against foreign invaders, such as microorganisms, toxins, allergens, or other foreign xenobiotics. Inammation is essential to generate both innate immunity, which is the rst line of body defense acquired from birth (nonspecic, less diverse, no memory), and adaptive immunity, which is an adaptation of the immune system to respond to particular infectious agents. It also functions to remove dead or damaged tissue as well as initiate the body’s healing and repair process. However, when inammation is chronic and uncontrolled, it becomes detrimental to the tissues and dangerous to human health. The four cardinal signs of inammation in its acute phase are redness, swelling, heat, and pain. The inammatory process involves a general accumulation of extravascular plasma proteins, including proinammatory cytokines and chemokines in addition to a variety of immune inammatory cell types. Inammation plays an important role in various diseases, such as rheumatoid arthritis, atherosclerosis, and asthma, all of which show a high prevalence globally. Chronic inammation occurs when the negative regulatory mechanism appears to be dysfunctional. Studies have shown that during an inammatory response, mediators, such as proinammatory cytokines, including interleukin IL-1, tumor necrosis factor (TNF), interferon (INF)-α, IL-6, IL-12, IL-18, and the granulocyte-macrophage colony-stimulating factor, are released. The body usually regulates the proinammatory response through a cascade of antagonism by antiinammatory cytokines, such as IL-4, IL-10, IL-13, IFN-α, and the transforming growth factor. The nuclear factor-κB (NF-κB), a transcription factor, also plays an important role in the inammatory response by regulating the expression of various genes encoding proinammatory cytokines, adhesion molecules, chemokines, growth factors, and inducible enzymes such as cyclooxygenase-2 (COX-2) and nitric oxide synthase (iNOS).1
