Iranian Journal of Allergy, Asthma and Immunology
Volume:11 Issue: 3, Sep 2012

Reactive oxygen species (ROS) are produced in many normal and abnormal processes in humans, including atheroma, asthma, joint diseases, cancer, and aging. Basal levels of ROS production in cells could be related to several physiological functions including cell proliferation, apoptosis and homeostasis. However, excessive ROS production above basal levels would impair and oxidize DNA, lipids, sugars and proteins and consequently result in dysfunction of these molecules withincells and finally cell death. A leading theory of the cause of aging indicates that free radical damage and oxidative stress play a major role in the pathogenesis of Alzheimer disease (AD). Because the brain utilizes 20% more oxygen than other tissues that also undergo mitochondrial respiration, the potential for ROS exposure increases. In fact, AD has been demonstrated to be highly associated with cellular oxidative stress, including augmentation of protein oxidation, protein nitration, glycoloxidation and lipid peroxidation as well as accumulation of Amyloid + (A+). The treatment with anti-oxidant compounds can provide protection against oxidative stress and A+ toxicity. In this review, our aim was to clarify the role of ROS in pathogenesis of AD and will discuss therapeutic efficacy of some antioxidants studies in recent years in this disease.

Atherosclerosis is a chronic inflammatory condition that affects the arterial wall. Oxidized lowdensity lipoprotein (ox-LDL) seems to have an important role in atherosclerotic plaque formation. This study was performed to investigate the effects of ox-LDL as well as PHA on proliferation and gene expression of peripheral blood mononuclear cells (PBMCs) in patients with atherosclerosis compared to healthy controls. Proliferation of PBMCs was assessed by BrdU assay, while gene expression was assessed by real-time PCR. Both PHA and ox-LDL significantly induced proliferation of PBMCs of patients and controls. PBMCs from controls showed significantly higher proliferation when stimulated with ox-LDL compared to patients. Expression of TGF-. was significantly lower in PBMCs from patients compared to healthy controls (p<0.001). Following simulation with PHA, TGF-. and Foxp3 gene expression levels in patients and controls were significantly decreased (p<0.001). Expression of Foxp in PBMCs treated with ox-LDL was significantly decreased in patients and controls. Decreased expression of TGF-. and Foxp3 genes after ox-LDL stimulation may be due to more sensitivity of Treg cells than effector T cells to ox-LDL. Presence of ox-LDL within atheroma could be associated with the diminished population of Treg cells in the atherosclerotic patients.

Pre-eclampsia is a pregnancy-specific syndrome that may be dangerous especially to the fetus. Different cytokines have been found to be elevated in women with pre-eclampsia and may have possible roles in the development of this disorder. Alleles of the interleukin-l beta (IL-l) and tumor necrosis factor alpha (TNF-%) genes are associated with pr-eeclampsia in several studies in different populations. The aim of the present study was to investigate the relationship between IL-l (C+3954T) and TNF-% (G-308A) gene polymorphisms with preeclampsia in north east of Iran (Khorasan province). This study included 54 diagnosed patients with pre-eclampsia and 50 normal pregnant women as control group. DNA was extracted from peripheral blood and the polymorphisms were determined by PCR-RFLP method. Data was analyzed using chi-square and Fisher’s exact tests. There was significant association between TNF-% (G-308A) genotype and pre-eclampsia (p=0.001) but we did not find any significant association between IL-l (C+3954T) genotype and pre-eclampsia (p=0.39). The present study might suggest a role for TNF-% in the development of pre-eclampsia; however, IL-l (C+3954T) polymorphism could not be considered as a marker of susceptibility to preeclampsia in our population.

Due to increasing worldwide water pollution, fish might be a source of excessive zinc, mercury, arsenic or manganese intake. The aim of this study was to evaluate if fish atopy/sensitization and fish consumption behavior are associated with eczema severity and blood levels of the 4 heavy metals. One-hundred and nineteen patients with eczema and 43 patients with miscellaneous noneczema skin diseases were studied. There were no differences in average weekly fish consumption and blood levels of the 4 heavy metals between eczema and non-eczema groups. Blood levels of these metals were generally within the upper limits of local reference ranges in all these patients. In eczema patients, freshwater fish consumption behavior in days-per-week was correlated with blood arsenic and mercury levels (rho=0.17, p<0.01 for both metals), but not with zinc or manganese. Levels of arsenic and mercury were also correlated with days of seawater fish consumption per week (arsenic: 0.38, mercury:. , p <0.05). Fish sensitization was present in 25% of patients with eczema. Nevertheless, there was no difference in terms of fish consumption behavior, eczema severity, quality of life, and heavy metal levels between eczema patients with or without fish sensitization. We conclude that without exceeding local normal reference ranges, blood arsenic and mercury levels correlated with fish consumption behavior. There is no evidence to suggest that fish sensitization is associated with more severe eczema (bad for eczema), or that patients have milder eczema with more days of fish consumption (good for eczema).

Chronic Idiopathic Urticaria is defined as recurrent hives occurring for at least 6 weeks. In the majority of cases, there is no identifiable underlying etiology despite extensive evaluation. A subset of these patients is classified as having autoimmune urticaria defined by the presence of a functional IgG antibody to the " subunit of the high-affinity IgE receptor (FceRIa) or to IgE. The aim of this study was to evaluate the effects of the drug atorvastatin in patients with chronic urticaria compared to the placebo. In this single-blind study, 50 patients suffering from chronic urticaria (15-45 years old) were selected and divided into two groups by simple randomization method. The first group was treated with atorvastatin and antihistamines and the second group (control group) was treated with placebo and antihistamines for 3 months. Urticaria severity was measured by score index, before and after the treatment course: ASST (Autologous serum skin test) was performed for all patients and sera were collected to measure cytokines. In cases, IL-5 decreased and IL-10 increased after treatment compared to the time point before treatment (p<0.05). All patients with severe utricaria according our scoring, had positive ASST.The patients with severe urticaria identified by urticaria score and ASST positivity had chronic idiopathic urticaria. By prescribing the Atorvastatin plus antihistamines in severe and resistant forms of urticaria, the use of more toxic medications like cytotoxic drugs may be avoided.

About 8% of the general population suffers from autoimmune diseases, from which 78% are women. One of the most important causes of thyroid diseases is autoimmunity in origin, and it seems that people with thyroid diseases present more signs of asthma. This study was therefore designed to investigate the frequency of autoimmune thyroid diseases in women suffering from bronchial asthma. In a cross-sectional study, 100 women with asthma and 100 women as control group were tested for thyroid function and anti-thyroid peroxidase antibody (anti-TPO Ab) measurements. The asthmatic patients were selected based on having chronic cough, dyspnea, wheezing and clinical examination of the chest. The diagnosis was confirmed by pulmonary function tests. Blood tests were done by electrochemiluminescence immunoassay method. No hyperthyroid patient was found in either group. Serum TSH and Total T4 levels were not statistically different between the two groups, but serum anti-TPO Ab levels in women with asthma (74±13.6 IU/ml) was significantly higher than control group (45.24±10.56 IU/ml). After adjusting the effect of age and BMI, the relationship between asthma and anti- TPO Ab (>50 IU/ml) was statistically significant (OR=3.3, P<0.01). Positive anti-TPO Ab in asthmatic patients may show presence of a hidden autoimmune thyroiditis in these patients. We suggested checking asthmatic patients for thyroid diseases.

Asthma is a clinical syndrome characterized by chronic airway inflammation, airway responsiveness, and expiratory airflow limitation. Nocturnal symptoms and decreases in lung function are common aspects of the asthma clinical syndrome. Nocturnal symptoms also appear to be associated with asthma-related mortality. In addition to its importance to the regulation of human circadian rhythms, an accumulating body of evidence also suggests that melatonin is also involved in the regulation of smooth muscle tone. For this reason, this study aimed to evaluate contraction and relaxation responses in tracheal smooth muscle rings obtained from rats treated with melatonin. Following administration of melatonin (50mg/kg/day) at the same time every day for 6 weeks, in vitro organ bath experiments were performed with rat tracheal preparations exposed to contractile (acetycholine and serotonin) and relaxant (theophylline and papaverine) agents. Melatonin treatment strengthened contraction responses, but did not affect relaxation responses in rat tracheal preparations. We think that melatonin might play a role in the pathogenesis of nocturnal asthma. Therefore, clinicians should be aware of the importance of melatonin to nocturnal exacerbation of asthma symptoms and alert asthmatic patients that use exogenous melatonin supplementation of its potential negative effects.

The frequency of allergic diseases such as allergic rhinitis is considerable in general population. Insect aeroallergens are important allergens which can induce airway inflammation. The aim of this study was to determine the prevalence of sensitization to insect aeroallergens in allergic rhinitis patients in Yazd as a desert city in Iran. A cross-sectional study was undertaken on 95 allergic rhinitis patients who were referred to allergy clinic of Yazd city. Skin prick tests (SPT) by standard extracts of three insect aeroallergens including Mosquito, Corn moth, Cockroach and two species of mites as common aeroallergens in allergic rhinitis (Dermatophagoid Farina, Dermatophagoid Peteronysinus) were done. SPT results showed that the most common insect aeroallergens were: mosquito (32.6%) followed by corn moth (26.3%) and cockroach (13.7%).The prevalence of SPT positive response to Dermatophagoid Peteronysinus, Dermatophagoid Farina were 8.4% and 7.4, respectively. These results demonstrated that sensitization to insect aeroallergens was significantly more common compared to mites in patients with allergic rhinitis in Yazd city, a city surrounded by deserts. High prevalence of skin reactivity to mosquito and corn moth as insect aeroallergens in Yazd city with hot and dry climate in contrast to humid regions such as north of Iran, where mites are more frequent, indicates differences in the prevalence of aeroallergen reactivity in various areas with different climates. Our study could highlight the importance of insect aeroallergens for clinicians for better diagnosis and management of patients with allergic rhinitis.

The Link between allergic rhinitis and asthma is well known. Bronchial hyperreactivity (BHR) may be present in rhinitis. The present study was aimed to compare airway responses in patients with rhinitis symptoms alone following exercise challenge, and to determine relationship of two different respiratory function tests. 98 subjects with rhinitis were investigated by spirometry and impulse oscillometry before and after exercise challenge. No significant difference was detected between spirometry and impulse oscillometry measurements before and after exercise challenge in subjects with rhinitis alone. No correlation between spirometry and impulse oscillometry indices was found in pre and postexercise stages. We therefore conclude that exercise challenge is not an appropriate test to determine airway hyperresponsive in subjects with rhinitis symptoms alone and findings of spirometry and impulse oscillometry are not interrelated.

Eczema is a common childhood atopic condition and treatment is with emollients, topical corticosteroids and avoidance of possible triggers. S. aurues colonization is a common complication. During exacerbation, intensification of treatment is needed to relieve the child from the miserable symptoms of pruritus and sleep disturbance. Systemic antibiotics against S. aureus may be required. We report an infant with eczema who presented with a generalised rash, cardiac arrest and septic shock. Kwashiorkor-like protein energy malnutrition was noted presumably due to deviated dietary practice. Childhood eczema is an eminently treatable atopic disease. Extreme alternative therapy seems not to be efficacious and may even be associated with grave sequelae.