Lipoxins: nature's way to resolve inflammation

An effective host defense mechanism involves inflammation to eliminate pathogens from the site of infection, followed by the resolution of inflammation and the restoration of tissue homeostasis. Lipoxins are endogenous anti-inflammatory, pro-resolving molecules that play a vital role in reducing excessive tissue injury and chronic inflammation. In this review, the mechanisms of action of lipoxins at the site of inflammation and their interaction with other cellular signaling molecules and transcription factors are discussed. Emphasis has also been placed on immune modulatory role(s) of lipoxins. Lipoxins regulate components of both the innate and adaptive immune systems including neutrophils, macrophages, T-, and B-cells. Lipoxins also modulate levels of various transcription factors such as nuclear factor κB, activator protein-1, nerve growth factor-regulated factor 1A binding protein 1, and peroxisome proliferator activated receptor γ and control the expression of many inflammatory genes. Since lipoxins and aspirin-triggered lipoxins have clinical relevance, we discuss their important role in clinical research to treat a wide range of diseases like inflammatory disorders, renal fibrosis, cerebral ischemia, and cancer. A brief overview of lipoxins in viral malignancies and viral pathogenesis especially the unexplored role of lipoxins in Kaposi's sarcoma-associated herpes virus biology is also presented.