Definition of Inflammation, Causes of Inflammation and Possible Anti-inflammatory Strategies

Abstract

Current definition of inflammation by its cardinal signs is obsolete and unsuitable for guiding adequate therapeutic strategies. Furthermore, present theory of the inflammatory process regarding vascular phenomena as essential for generation of cardinal signs is invalid and unable to explain well established empirical facts, particularly the extent of the osmotic pressure and temperature variations within the inflamed tissue. From five cardinal signs, there is actually just one specific macroscopic sign of inflammation, namely localized edema. Further, the driving force for tissue fluid accumulation is defined in biochemical terms and as such taken for the definition of the inflammatory process. Inflammation may be defined as a degenerative process which is intense enough to cause local accumulation of low molecular weight catabolic products, which in turn elevates tissue osmotic pressure that attracts extra fluid, with or without heat release sufficient for significant elevation of tissue temperature. This process is in a sharp contrast to the pathogenesis of burns, where externally applied heat causes a process that is in essence opposite to inflammation, bearing only some superficial similarities with the latter. The inflammatory process is itself a pathological process, whereas the natural anti-inflammatory response that ensues after acute inflammation tends to reverse tissue homeostasis towards normality and should therefore be regarded as a true defensive reaction of the affected tissue. Based on the therapeutic principle of reverse thermodynamics, heat application to the inflamed tissue is an obvious, yet non-exclusive therapeutic choice that follows from the given universal definition of inflammation.