Histopathology of the skin in rheumatic diseases.

Rheumatological systemic autoimmune diseases, such as connective tissue diseases, rheumatoid arthritis or spondyloarthritis, are characterized by the presence of joint involvement associated with extra-articular manifestations. Among them, cutaneous diseases are often the most relevant and representative clinical manifestation, as in psoriatic arthritis, scleroderma or systemic lupus erythematosus. In this context, it is useful for rheumatologists to understand better skin diseases and their histopathological features. Evaluation of skin biopsy specimens can be helpful not only to confirm the diagnosis in both classic and clinically atypical variants, but also to improve further our knowledge of the pathogenetic mechanisms and the close link between skin and articular diseases. In this review, we discuss the clinical features, diagnostic evaluation and the histopathological features of skin manifestation of the most relevant rheumatological autoimmune diseases.

ENOX2 (or tNOX): a new and old molecule with cancer activity involved in tumor prevention and therapy.

Cancer includes a number of related diseases due to abnormal cell proliferation that spreads to nearby tissues. Many compounds (physical, chemical and biological) have been used to try to halt this abnormal proliferation, but the therapeutic results are poor, due also to the side effects. It has been reported that ecto-nicotinamide adenine dinucleotide oxidase di-sulfide-thiol exchanger 2 (ENOX2), also known as tumor-associated nicotinamide adenine dinucleotide oxidase (tNOX), was found to be located on the cancer cell surface, essential for cancer cell growth. Capsaicin and other anti-oxidants are capable of inhibiting tNOX, causing apoptosis of cells, exerting anti-tumor activity. It is interesting that some authors reported that ENOX2 is present in the serum of cancer patients several years before the clinical symptoms of the tumor. However, this result has to be confirmed. In this article we discuss ENOX2 and its inhibition as a hope of improving cancer therapy.

Is vitamin E an anti-allergic compound?

Vitamin E is found in eight forms in nature which include four tocopherols (alpha, beta, gamma and delta) and four tocotrianols (alpha, beta, gamma and delta). The classic effect of vitamin E is to reduce and prevent oxygen damage to the tissue and is useful for the treatment of pain, inflammation and allergic reactions. In addition to antioxidant activity, vitamin E also has a number of different and related functions. It protects against cancer, improves immune response, lowers the incidence of infectious diseases, cardiovascular diseases and is protective in allergy and asthma risk, and other disorders. Vitamin E increases n-6 polyunsaturated fatty acid (PUFA) and decreases n-3 PUFA, an effect that diminishes asthma and allergic diseases. Moreover, vitamin E regulates vascular cell adhesion molecule-1 (VCAM-1)-dependent leukocyte migration through its oxidant and non-antioxidant effect. Furthermore, vitamin E modulates the endothelial function by altering VCAM-1-induced oxidative activation of endothelial cell PKCα. However, vitamin E is not consistently associated with asthma and/or allergy, and in some cases there are conflicting results on allergy and inflammatory diseases. The association of vitamin E and allergy appears to be very complex, and further study needs to clarify this dilemma.

IMMUNOMODULATORY EFFECTS OF VITAMIN D ON SKIN INFLAMMATION.

Vitamin D has a major role in calcium absorption and maintenance of healthy bones. Vitamin D is also involved in cancer, cardiovascular system, allergic diseases, immune regulation and immune disor¬ders. Irradiation of food as well as animals produces vitamin D and more than 90% of previtamin D3 synthesis in the skin occurs in the epidermis. Vitamin D receptor has been found in many cells including T and B lymphocytes, macrophages, mast cells, NK cells and Tregs, and it selectively binds with high affinity to its ligand. Vitamin D binds its receptor VDR, resulting in transcription of a number of genes playing a role in inhibition of MAPK. Its effect may be also mediated by the direct activation of PKC. Vitamin D has the ability to suppress inflammatory cytokines such as TNF, IL-1, IFN-gamma and IL-2; while it increases the generation of anti-inflammatory cytokines IL-4 and IL-10. In B cells, vitamin D3 have also been shown to suppress IgE antibody class switch partly through the inhibition of NF-kB. Here we discuss the relationship between vitamin D, immunity and skin disorders.

Role of TNF in mast cell neuroinflammation and pain.

Inflammatory mediators, such as cytokines, chemokines and arachidonic acid compounds, lead to vascular permeability and dilation and increase sensitization and pain receptors. Proinflammatory cytokines, including tumor necrosis factor, are involved in the etiology of clinical neurological disorders. These cytokines activate nuclear factor-κB (NF-κB) which leads to the activation of different inflammatory genes. TNF implicated in neurological disorders has an important role in the activation of microglia and astrocytes. The inhibition of TNF may lead to the decrease of microglia activation and can be useful for therapeutic intervention. TNF, at the site of nerve injury may activate mast cells (MCs) which mediate pathologic events such as headache and pain. TNF is the only cytokine stored in mast cells and can be rapidly released along with biogenic amines after MC stimulation. Activation of MCs leads to NF-κB and AP1 generation with release of many cytokines including TNF, IL-33 and IL-1. In this paper we discuss the role of TNF in MC activation, mediating pain and neurological disorders.

Relationship between serotonin and mast cells: inhibitory effect of anti-serotonin.

Serotonin (5-HT) is an important neurotransmitter that acts in both central and peripheral nervous system, and has an impact on cell proliferation, migration and apoptosis. 5HT exerts its effects via several receptors. Treatment with anti-5-HT receptors diminish the severity of contact allergy in experimental animals, an effect mediated by mast cells; while an agonist reduces the stress level and relieves pruritus in patients with atopic dermatitis. Mast cells are important for both innate and adaptive immunity and they are activated by cross-linking of FceRI molecules, which are involved in the binding of multivalent antigens to the attached IgE molecules, resulting in a variety of responses including the immediate release of potent inflammatory mediators. Serotonin is present in murine mucosal mast cells and some authors reported that human mast cells may also contain serotonin, especially in subjects with mastocytosis. Here we report the interrelationship between mast cells, serotonin and its receptor inhibitor.

Interrelationship between IL-3 and mast cells.

It is well established that mast cells, which are found in the tissues in the proximity of small blood vessels and post-capillary venules, play a key role in the early phase of IgE-mediated allergic reactions. A greatly expanded understanding of the biology of IL-3 has emerged since the early 1980s. IL-3 is a specific factor that stimulates the growth of hematopoietic stem and progenitor cells of a variety of lineages and can promote the proliferation of certain classes of lymphocytes distinct from those that are dependent on IL-2. IL-3 has been identified among the most important cytokines for regulation of mast cell growth and differentiation, migration and effector function activities of many hematopoietic cells. IL-3 termed multi colony-stimulating-factor (multi-CSF) or mast cell growth factor (MCGF) is a haematopoietic growth factor which stimulates the formation of colonies for erythroid, megakaryocytic, granulocytic and monocytic lineages. It is predominantly produced by activated T cells, natural killer (NK) cells and mast cells and supports the growth-promoting effects of SCF on mast cell precursors. IL-3 causes severe hypersensivity reactions and plays a pivotal role in exacerbating the inflammatory response in vivo. Here we report the interrelationship between IL-3 and mast cells.

Role of mast cells in atherosclerosis: a classical inflammatory disease.

Atherosclerosis is an inflammatory disease and hyperlipidaemia is one of the main risk factors for aging, hypertension and diabetes. Variance in plasma LDL cholesterol concentration may be associated with differences in cardiovascular disease risk and high levels of lipids are associated with increased risk of developing atherosclerosis. Macrophages, which generate pro-inflammatory cytokines, mainly interleukin-1 (IL-1) and tumor necrosis factor-α (TNF-alpha), are deeply involved in atherosclerosis, as well as mast cells which generate several cytokines, including IL-6 and IFN-gamma, and chemokines such as eotaxin, MCP-1 and RANTES involved in monocyte recruitment and differentiation in the arterial wall. In addition, mast cells participate in lipid retention and vascular cell remodeling, and are mediators of innate and adaptive immunity during atherosclerosis. Mast cells which accumulate in the human arterial intima and adventitia during atherosclerotic plaque progression, release vasoactive and angiogenic compounds, and pro-inflammatory mediators, such as arachidonic acid metabolites, histamine, cytokines/chemokines, platelet activating factor (PAF) and proteolytic enzymes. Mast cells can be activated by pro-inflammatory stimuli, including cytokines, hypercholesterolemia, and hyperglycemia, and trigger the endothelial expression of adhesion molecules such as P-selection, vascular cell adhesion molecule-1 (VCAM-1) and chemokines which mediate the recruitment and adhesion of leukocytes. The participation of mast cells in atherosclerosis is still an enigma and it may be of therapeutic interest to clarify this process.

Impact of mast cells on the skin.

When through the skin a foreign antigen enters it provokes an immune response and inflammatory reaction. Mast cells are located around small vessels that are involved in vasaldilation. They mature under the influence of local tissue to various cytokines. Human skin mast cells play an essential role in diverse physiological and pathological processes and mediate immediate hypersensitive reaction and allergic diseases. Injection of anti-IgE in the skin or other agents that directly activate mast cells may cause the decrease in vascular tone, leakage of plasma and may lead to a fall in blood pressure with fatal anaphylactic shock. Skin mast cells are also implicated as effector cells in response to multiple parasites such as Leishmania which is primarily characterized by its tissue cutaneous tropism. Activated macrophages by IFNgamma, cytotoxic T cells, activated mast cells and several cytokines are involved in the elimination of the parasites and immunoprotection. IL-33 is one of the latest cytokines involved in IgE-induced anaphylaxis and in the pathogenesis of allergic skin disorders. IL-33 has been shown in epidermis of patients with psoriasis and its skin expression causes atopic dermatitis and it is crucial for the development of this disease. Here we review the impact of mast cells on the skin.

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.

Luteolin inhibits mast cell-mediated allergic inflammation.

Mast cells are ubiquitous in the body and multifunctional immune cells; they are known to be primary responders in allergic reactions, orchestrating strong responses to minute amounts of allergens. Mature mast cells perform important beneficial roles in host defense, both in IgE-dependent immune responses to certain parasites and in natural immunity to bacterial infection. In IgE-associated biological responses, the crosslinking of FcεRI-bound IgE with multivalent antigens initiate the activation of mast cells by promoting aggregation of FceRI. This cross-linking receptor-bound IgE by multivalent Ag initiates a cascade of intracellular reactions leading to mediator release such as proinflammatory mediators, chemokines and cytokines. Luteolin belongs to a flavone group of compounds called flavonoids, it has anti-oxidant properties, inhibits some cancer cell proliferation and exerts a regulatory effect on mast cell-mediated inflammatory diseases and allergy. Here we report the impact of luteolin on mast cell activation.

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.

Endothelial cells, cholesterol, cytokines, and aging.

It has been reported that high levels of cholesterol and triglycerides are associated with increased risk of developing atherosclerosis and shorter life. In fact, vascular endothelial dysfunction occurs during the human aging process. Accumulation of lipids in vascular endothelium activates leukocytes to produce cytokines and chemokines which recruit macrophages. On the other hand, macrophages augment inflammatory response and secrete vascular endothelial growth factor, a key cytokine that mediates angiogenesis and inflammatory response. In addition, hyperlipidaemia is one of the main risk factors for aging, hypertension and diabetes. Here, we review the interrelationship between endothelial cells, high level of cholesterol, and aging.

Biomechanical modification and sense motor control of body posture after plastic surgery.

Plastic surgery offers a quite unique window on abrupt and permanent modifications of a human's body schema. Its impact is comparable to amputations or other severe injuries, with the evident advantage from the experimenter's (and patient's) point of view that it is planned, allowing longitudinal studies and quantification of the weight and distribution of modified bodily masses (e.g., weight of the prosthesis). One potential drawback is that modifications due to (aesthetic) plastic surgery are often too little to be revealed by motor control tasks, making it difficult to measure the time course of body schema readaptation. The aim of our study is measuring the capability of the body scheme to re-adapt to significant and abrupt changes, such as the distribution of mass centers, and in particular to assess what is the time course of such re-adaptation. For this reason, we have carried out a longitudinal study on postural modifications on a population of female patients (N = 30) who were subjected to additive or reductive plastic surgery. Posture and stabilometry evaluations were performed before surgery (T0), and after 1 months (T1), 4 months (T2), and 1 year (T3). Posture was reconstructed from spatial tracking system (FastrackTM Polhemus) recordings. Stabilometry analysis was performed by force platform (Globus Italia). The results document a modification in posture and a significant increase in the sway area after body mass alterations. Posture and stabilometry data return to equilibrium after 1 year. Our data suggest that posture control relies on, at least in part, feedforward than only on feedback strategies.

Exaggerated imiquimod application site reactions in the context of systemic tumor necrosis factor-alpha inhibition: more than a coincidental occurrence?

Topical imiquimod and tumor necrosis factor (TNF)-alpha inhibitors have gained wide acceptance as safe and effective treatments for non-melanoma skin cancer (NMSC) and moderate to severe psoriasis, respectively. While mild to moderate application site reactions (ASRs) are a well-known and common phenomenon associated with imiquimod, the potential of TNF-alpha blockers to elicit cutaneous inflammatory reactions has only recently been recognized. We present two cases of severe, atypical ASRs which occurred during NMSC treatment with imiquimod in the context of infliximab administration for psoriasis, and consider the grounds supporting a non-fortuitous association. To date, no relation has ever been suggested between TNF-alpha inhibitors and increased susceptibility to developing exaggerated ASRs with imiquimod. We believe that this subject deserves further analysis; meanwhile, increased attention should be drawn to the possibility of this adverse interaction, as simultaneous treatment with TNF-alpha blockers and imiquimod is becoming increasingly frequent in daily practice.

Atherosclerosis: a classic inflammatory disease.

Atherosclerosis is an inflammatory disease due to a diet high in saturated fat, hypercholesterolemia, obesity, hypoglycemia, etc. mainly mediated by the infiltration of macrophage and T cells into the vascular wall. Once the endothelial is damaged monocytes penetrate the tissue and are transformed in scavenger cells. Upon stimulation of Th1 cells, a group of cytokines is released and contributes to the inflammatory response of atherosclerotic tissue. When macrophages proliferate they amplify inflammatory response through the secretion of growth factors and cytokines such as TNF and IL-1. In addition, chemokines such as RANTES and other C-C chemokines are generated, and matrix metalloprotinease 9 (MMP-9) are produced by activated monocytes. However, the immune system in atherosclerosis still remains unclear. Here, in this study we revisited the inter-relationship between atherosclerosis and inflammation.

The use of mechanical acoustic vibrations to improve abdominal contour.

Adaptive effects caused by mechanical acoustic vibrations on the neuromuscular system are widely described. These vibrations applied to the muscle belly cause the "vibration tonic reflex" characterized by an improvement in power contraction of the stimulated muscle. Mechanical acoustic vibrations of moderate strength placed on limited body areas produce a positive muscle activity without damage. A prospective study from January to September 2006 investigated 60 sedentary patients presenting with muscular hypotrophy associated or not associated with lipodystrophy of the abdominal region who desired a substantial contour improvement of such area without invasive procedures. Of these patients, 40 were subjected to a treatment protocol with mechanical acoustic vibrations applied to the abdomen, associated or not associated with physical aerobic exercise of moderate intensity. The remaining 20 patients engaged only in the physical training. The study aimed to evaluate whether the application of mechanical acoustic vibrations could improve body contour.