ABSTRACT
Inammation is part of the complex biological response to harmful stimuli, such as pathogens or damaged cells. Acute inammation is a short-term process, usually appearing within a few minutes or hours and ceasing upon the removal of the injurious stimulus. It is classically characterized by four cardinal signs: dolor (pain), calor (heat), rubor (redness), and tumor (swelling). Inammation is also a protective process of the organism to remove the injurious stimuli and to initiate the healing process. Inammation is not always accompanied with infection,
4.1 Inammation .......................................................................................................................... 51 4.2 Interaction between Hypoxic Environment and Inammation .............................................. 52
4.2.1 Hypoxia-Induced Inammation ................................................................................. 52 4.2.2 Inammation-Induced Hypoxia ................................................................................. 52
4.3 Canonical Signaling Pathway to Hypoxia-Inducible Factor Activation .................................54 4.3.1 Induction of HIF Activation by Continuous Hypoxia ................................................54 4.3.2 Induction of HIF by Intermittent Hypoxia ................................................................. 55
4.4 Oxygen Tension-Independent Activation of HIF .................................................................... 55 4.4.1 Pro-Inammatory Cytokines and Chemokines and HIF ........................................... 55
4.5 Cross Talk between NF-κB and HIF ...................................................................................... 56 4.6 Immunocompetent Cells and HIF .......................................................................................... 56
4.6.1 Macrophages and Dendritic Cells ..............................................................................56 4.6.2 Neutrophils ................................................................................................................. 57 4.6.3 T Lymphocytes ........................................................................................................... 58 4.6.4 B Lymphocytes ........................................................................................................... 59 4.6.5 Mast Cells ................................................................................................................... 59
4.7 Impact of Anti-Inammatory Drugs on HIF Activity ............................................................ 59 4.8 Inammatory Disorders and HIF ........................................................................................... 59
4.8.1 Infection ...................................................................................................................... 59 4.8.2 Sepsis ..........................................................................................................................60 4.8.3 Wound Healing ........................................................................................................... 61
4.9 Conclusions and Future Directions ......................................................................................... 61 Take-Home Messages ...................................................................................................................... 62 References ........................................................................................................................................ 63
even in cases where inammation is caused by infection. Although infection is caused by a microorganism, inammation is one of the responses of the organism to the pathogen. It is considered as a mechanism of innate immunity, as compared to adaptive immunity, which is speciœc for each pathogen.
