Vascular endothelial growth factor (VEGF), mast cells and inflammation.

Vascular endothelial growth factor (VEGF) is one of the most important inducers of angiogenesis, therefore blocking angiogenesis has led to great promise in the treatment of various cancers and inflammatory diseases. VEGF, expressed in response to soluble mediators such as cytokines and growth factors, is important in the physiological development of blood vessels as well as development of vessels in tumors. In cancer patients VEGF levels are increased, and the expression of VEGF is associated with poor prognosis in diseases. VEGF is a mediator of angiogenesis and inflammation which are closely integrated processes in a number of physiological and pathological conditions including obesity, psoriasis, autoimmune diseases and tumor. Mast cells can be activated by anti-IgE to release potent mediators of inflammation and can also respond to bacterial or viral antigens, cytokines, growth factors and hormones, leading to differential release of distinct mediators without degranulation. Substance P strongly induces VEGF in mast cells, and IL-33 contributes to the stimulation and release of VEGF in human mast cells in a dose-dependent manner and acts synergistically in combination with Substance P. Here we report a strong link between VEGF and mast cells and we depict their role in inflammation and immunity.

Comparison of beneficial actions of non-steroidal anti-inflammatory drugs to flavonoids.

Inflammation is involved in increasing number of diseases necessitating the development of new, effective and safe treatments. Non steroidal anti-inflammatory drugs (NSAIDs) have been helpful in many instances, but they only inhibit cyclooxygenase (COX), but not the generation or actions of cytokines. Instead, some natural flavonoids have multiple anti-inflammatory effects, including COX inhibition, and a much safer profile. Increasing evidence indicates that inflammation plays a critical role in the pathogenesis of many diseases that also involve mast cells. Consequently, the need for new, effective and safe anti-inflammatory drugs is all the more urgent. Corticosteroids are quite potent, but have many adverse effects such as increased risk of infections, osteoporosis, glaucoma and depression. Biological agents such anti-TNF are useful in certain conditions, such as rheumatoid arthritis and psoriasis, but has been associated with increased risk of infection and leukemia.

IL-36 receptor antagonist with special emphasis on IL-38.

IL-36 is another family member of IL-1 and induces the production of proinflammatory cytokines and activates MAPK and NFkB pathways. IL-36 is a common mediator of innate and adaptive immune response and is inhibited by IL-36 receptor antagonist (RA). IL-36RA acts on IL-36 receptor ligand which exerts proinflammatory effect in vivo and in vitro. IL-38 binds to IL-36 receptor as does IL-36RA and has similar biological effects on immune cells. IL-38 is also a member of IL-1 cytokine and shares some characteristics of IL-1RA, binding the same IL-1 receptor type I. IL-38 plays a role in the pathogenesis of inflammatory diseases, exerting protective effect in some autoimmune diseases. Both IL-38 and IL-36RA have an anti-inflammatory biological effect, however in some cases have contrary effects.

Impact of IL -9 and IL-33 in mast cells.

Cytokines serve as chemical communicators from one cell to another and most of them have pro-inflammatory activity. Mast cells have been recognised as important mediators of the pathogenesis of allergy and inflammation, suggesting a role for IL-33-mediated mast cell activation. IL-33 was recently identified as a ligand for the orphan IL-1 family receptor T1/ST2 and is mainly expressed by mast cells, fibroblasts, epithelial cells, and endothelial cells, particularly in high endothelial venules. IL-33 is a potent inducer of pro-inflammatory cytokines such as IL-1, IL-6, IL-13 and TNF, and chemokines (MCP-1), by mast cells. Substance P is capable to induce VEGF from mast cells, and IL-33, the newest pro-inflammatory member of the IL-1 cytokine family, augments the effect of SP in VEGF transcription and translation protein. IL-9 is a pleiotropic and is expressed by multiple T helper (TH) cell subsets. IL-9 promotes the expression of mast cell pro-inflammatory cytokines in vitro and is involved in Th2 responses. This article focuses on recent developments of mast cells, IL-9 and IL-33, and recent literature and investigations were reviewed.

Interleukin-9 and mast cells.

Mast cells are granulated hematopoietic cells derived from stem cells that reside in nearly all tissues and are involved in protection of a host from bacterial infection with a protective and pathogenic activity. Mast cells are important for both innate and adaptive immunity in tissues which are in close contact with the environment. These cells express proinflammatory cytokines such as IL-1, IL-6, IL-8 and tumor necrosis factor which are necessary for innate immunity. Mast cells also produce interleukin-9 and enhance mast cell expression of several cytokines including IL-1beta, IL-5, IL-6, IL-9 and IL-13. In addition, IL-9 can induce mast cell production of TGF-beta which can have proinflammatory downstream effects. IL-9 can function as either a positive or a negative regulator of immune responses and can have a detrimental role in allergy and autoimmunity. Furthermore, IL-9 contributes to disease by promoting mast cell expansion and production of IL-13 which in turn contributes to airway hyperresponsiveness. Here, in this editorial we review the interrelationship between IL-9 and mast cells.

Nutrition and cancer prevention.

Cancer cells invade surrounding tissues and metastasize to distant sites. Diet high in fat is a strong link to, and perhaps causes, a high incidence of tumours. Trans-fatty acid might impair the function and it could be involved in the development of cancer. Cholesterol is also strongly suspected to be involved in the development of tumours, therefore it is important for everyone to eat well, especially for people with cancer to prevent the body tissues from breaking down and helping to rebuild the normal tissue that may have been affected by the treatments. Factors secreted by adipocytes and macrophages such as TNF-alpha and other inflammatory proteins are involved in inflammation in cancer. In addition, MCSF which up-regulates adipocyte tissue is also important for the stimulation of fat cell proliferation and is expressed by human adipocytes. Many cytokines, such as IL-1, IL-6, IL-8, IL-32, IL-33 and MCP-1, are biomarkers for cancer and chronic diseases along with transcription factors NFκB and AP-1; these last two factors are important bioactive substances on the molecular mechanism of the control of genes which in turn affect cellular metabolism. In this paper we revisit the interrelationship between cancer and metabolism.

Impact of neuropeptide substance P an inflammatory compound on arachidonic acid compound generation.

There is much evidence that neuropeptide substance P is involved in neurogenic inflammation and is an important neurotransmitter and neurmodulator compound. In addition, substance P plays an important role in inflammation and immunity. Macrophages can be activated by substance P which provokes the release of inflammatory compounds such as interleukins, chemokines and growth factors. Substance P is involved in the mechanism of pain through the trigeminal nerve which runs through the head, temporal and sinus cavity. Substance P also activates mast cells to release inflammatory mediators such as arachindonic acid compound, cytokines/chemokines and histamine. The release of these chemical mediators is crucial for inflammatory response. Among these mediators there are prostoglandins and leukotrines. Here we review the impact of substance P on inflammatory compounds.