Histamine release by inorganic cations from mast cell granules isolated by different procedures

Tanshinone IIA prevents left ventricular remodelling via the TLR4/MyD88/NF-κB signalling pathway in rats with myocardial infarction

In this study, we aim to investigate the role of tanshinone IIA in myocardial infarction (MI), especially in left ventricular remodelling (VR) and the underlying mechanism involving the TLR4/MyD88/NF‐κB signalling pathway. Sprague‐Dawley (SD) rats (n = 96) were selected, and 12 of them underwent sham surgery. The remaining 84 rats were subjected to MI modelling. HE and MT staining were carried out to estimate infract size, histopathological changes and fibrosis degree. Macrophage infiltration and cardiomyocyte apoptosis were evaluated by immunohistochemistry and TUNEL staining. Reverse transcription quantitative polymerase chain reaction (RT‐qPCR) and Western blotting were used to determine the expression levels of TLR4, MyD88 and NF‐κB. Serum levels of IL‐2, IL‐6, IL‐8, TNF‐a, procollagen I Cpropeptide (PICP), and procollagen III N‐propeptide (PIIINP) were measured using enzyme‐linked immunosorbent assay (ELISA). The heart weight/body weight, mean arterial pressure (MAP), left ventricular end‐systolic pressure (LVESP), +dP/dt and −dP/dt increased while the ventricular function and the left ventricular end‐diastole pressure (LVEDP) decreased in MI rats. Compared with the rats undergoing sham surgery, MI rats showed larger infarct size, severer fibrosis, higher expression levels of TLR4, NF‐κB‐P65, MyD88, IL‐2, IL‐6, IL‐8, TNF‐a, PICP and PIIINP as well as enhanced macrophage infiltration, cardiomyocyte apoptosis. After treatment with tanshinone IIA combined with LPS for 4 weeks, the rats showed better condition than those treated with only LPS. These results indicate that tanshinone IIA attenuates MI and prevents left VR. Importantly, inhibition of TLR4/MyD88/NF‐κB signalling pathway is a key step in this process.

Pathophysiological mechanisms of exercise-induced anaphylaxis: an EAACI position statement

This document is the result of a consensus on the mechanisms of exercise-induced anaphylaxis (EIAn), an unpredictable and potentially fatal syndrome. A multidisciplinary panel of experts including exercise physiologists, allergists, lung physicians, paediatricians and a biostatistician reached the given consensus. Exercise-induced anaphylaxis (EIAn) describes a rare and potentially fatal syndrome in which anaphylaxis occurs in conjunction with exercise. The pathophysiological mechanisms underlying EIAn have not yet been elucidated although a number of hypotheses have been proposed. This review evaluates the validity of each of the popular theories in relation to exercise physiology and immunology. On the basis of this evidence, it is concluded that proposed mechanisms lack validity, and it is recommended that a global research network is developed with a common approach to the diagnosis and treatment of EIAn in order to gain sufficient power for scientific evaluation.

Exercise-induced anaphylaxis: A clinical view

Exercise-induced anaphylaxis (EIA) is a distinct form of physical allergy. The development of anaphylaxis during exertion often requires the concomitant exposure to triggering factors such as intake of foods (food dependent exercise-induced anaphylaxis) or drugs prior to exercise, extreme environmental conditions. EIA is a rare, but serious disorder, which is often undetected or inadequately treated. This article summarizes current evidences on pathophysiology, diagnosis and management. We reviewed recent advances in factors triggering the release of mediators from mast cells which seems to play a pathogenetic role. A correct diagnosis is essential to avoid unnecessary restricted diet, to allow physical activity in subjects with EIA dependent from triggering factors such as food, and to manage attacks. An algorithm for diagnosing EIA based on medical history, IgE tests and exercise challenge test has been provided. In the long-term management of EIA, there is a need for educating patients and care-givers to avoid exposure to precipitating factors and to recognize and treat episodes. Future researches on existing questions are discussed.

Allergy and sports in children

Physical activity is beneficial for children with positive outcomes for mental and physical well-being. Allergic conditions unique to the sporting arena may serve as an impediment to participation in physical activity for allergic children. A common example is exercise-induced asthma; less common activity-related allergic conditions include food-dependent exercise-induced anaphylaxis, exercise-induced anaphylaxis, and exercise-induced urticaria. Allergic children may also be at risk of allergic reactions when exposed to allergens that are more commonly found in the sports environment, e.g., latex, sports drinks, and medications such as NSAIDs. Recent advances in our understanding of the patho-physiological and immunologic mechanisms that may account for these conditions have facilitated more effective and safer management strategies. There are also important immunologic lessons to be learnt with respect to specific physical factors that may result in diminished allergen tolerance; indeed, these lessons may facilitate safer allergen desensitisation regimens. The role of the immune system in exercise-induced immunoallergic syndromes, clinical aspects, and diagnostic and therapeutic approaches are discussed in this review.