Inflammatory response, tissue

Human bodies are constantly exposed to a plethora of bacteria, viruses, and other inflammatory substances. To combat these infections and toxic agents, the body has developed a carefully regulated inflammatory response system. Part of that response is the orderly migration of leukocytes to sites of inflammation. Leukocytes literally roll along the vascular wall and into the tissue site of inflammation. This rolling movement is mediated by reversible adhesive interactions between the leukocytes and the vascular surface. 

Histamine. A diamine found in plant and animal tissues. It is involved in inflammatory responses. 

The wide range of inflammation-related factors that adipocytes secrete is linked to the inflammatory response that the tissue exhibits in obesity [1]. Obesity in general, like an increasing number of other diseases, is characterised by a state of mild chronic inflammation, and adipose tissue plays a central role in this. The production of most inflammation-related adipokines increases markedly in obesity and there is an elevated circulating level of a number of these factors as well as of other inflammatory markers such as C-reactive protein (CRP). The increased production of inflammatory adipokines (and decreased production of adiponectin with its anti-inflammatory action) in the obese is considered to play a critical role in the development of the obesity-associated pathologies, particularly type 2 diabetes and the metabolic syndrome [1]. 

In the very early phases of the acute inflammatory response most of the cells invading the damaged area are polymorphonuclear neutrophils, also denoted as PMNs, which serve as initial line of defense and source of proinflammatory cytokines. These cells, which usually live for 4-5 days, circulate in the blood until they are attracted by chemokines into injured tissues. Whereas physical injury does not recruit many neutrophils, infections with bacteria or fungi elicit a striking neutrophil response. The characteristic pus of a bacterial abscess is composed mainly of apoptotic (apoptosis) and necrotic PMNs. Emigration of neutrophils from the blood starts with a process denoted as margination where neutrophils come to lie at the periphery of flowing blood cells and adhere to endothelial cells (Fig. 1). L-Selectin is expressed... 

The objectives of the inflammatory response can be viewed as a hierarchical ordered panel of events. The most successful consequence of an inflammatory response is the complete restoration of function and structure of the affected tissue, also denoted as resolution. If this is not possible, inflammation aims for healing by repair and replacement of lost tissue by scar tissue. 

Melanocortin peptides are potent anti-inflammatory agents displaying beneficial effects in diseases ranging from cardiovascular to arthritis to obesity to name a few. Within an inflammatory context, they have the ability to switch off early production of cytokines and at later stages they increase levels of anti-inflammatory proteins that lead to the resolution of the host inflammatory response potentially restoring homeostasis to the tissue. They could eventually be viewed as an alternative to glucocorticoids, as their mode of action often resembles that seen... 

After 7 days, the acute inflammatory response at the implantation site was evaluated. Bisphenol A resulted in a moderate level of irritation at the implantation site and was clearly the least biocompatible test substance. Tyrosine derivatives containing the benzyloxycar-bonyl group caused a slight inflammatory response, while all other tyrosine derivatives produced no abnormal tissue response at all. These observations indicate that tyrosine dipeptide derivatives, even if fully protected, are more biocompatible than BPA, a synthetic diphenol. ... 

The model concerning wound healing occurs in two phases (1) pro-inflammatory responses (Glaser and Kiecolt-Glaser 2005 Moore 1999 Tidball 2005 Whelan et al. 2005) which are needed to ensure adequate clearance of pathogen at the site of tissue injury, as well as, (2) re-epithelialization and neovascularization events (Frantz et al. 2005 Moore 1999 Naldini and Carraro 2005 Olah and Caldwell 2003 Whelan et al. 2005) to ensure proper wound closure. It is important to note that the resolution of pathogen clearance is essential in order for the wound closure processes to take place (Robson 1997). 

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