Alterations in Plasma Essential Trace Elements Selenium, Manganese, Zinc, Copper, and Iron Concentrations and the Possible Role of these Elements on Oxidative Status in Patients with Childhood Asthma

Saux

The Journal of Immunology

et al. 2007

Asthma is driven by allergic airway inflammation and involves increased levels of oxidative stress. This has led to speculation that antioxidants like selenium (Se) may play important roles in preventing or treating asthma. We fed diets containing low (0.08 parts per million), medium (0.25 parts per million), or high (2.7 parts per million) Se to female C57BL/6 mice and used an established OVA challenge protocol to determine the relationship between Se intake and the development of allergic airway inflammation. Results demonstrated that mice fed medium levels of Se had robust responses to OVA challenge in the lung as measured by lung cytokine levels, airway cellular infiltrate, eosinophilia, serum anti-OVA IgE, airway hyperreactivity, goblet cell hyperplasia, and phosphorylated STAT-6 levels in the lung. In contrast, responses to OVA challenge were less robust in mice fed low or high levels of Se. In particular, mice fed low Se chow showed significantly lower responses compared with mice fed medium Se chow for nearly all readouts. We also found that within the medium Se group the expression of lung glutathione peroxidase-1 and liver selenoprotein P were increased in OVA-challenged mice compared with PBS controls. These data suggest that Se intake and allergic airway inflammation are not related in a simple dose-response manner, which may explain the inconsistent results obtained from previous descriptive studies in humans. Also, our results suggest that certain selenoproteins may be induced in response to Ag challenges within the lung.

Section: Discussionmentioning

confidence: 57%

mentioning

confidence: 99%

A Role for Dietary Selenium and Selenoproteins in Allergic Airway Inflammation

Saux

The Journal of Immunology

et al. 2007

“…However, correlations between Se status and asthma have not been consistently demonstrated. For example, a number of epidemiological studies have reported that asthma incidence, prevalence, or severity is associated with reduced Se status (52,69,92,120,130,170,190,202,228,244). This is in contrast to findings in a large, multi-regional study conducted under the Global Allergy and Asthma European Network, in which asthma prevalence/severity data from 14 centers in Europe showed no significant association between Se status and asthma levels (33).…”

Section: Intestinal Inflammation and Food-borne Illnessesmentioning

confidence: 87%

The Role of Selenium in Inflammation and Immunity: From Molecular Mechanisms to Therapeutic Opportunities

Huang

Rose

Antioxidants & Redox Signaling

2012

682

496

Dietary selenium (]Se), mainly through its incorporation into selenoproteins, plays an important role in inflammation and immunity. Adequate levels of Se are important for initiating immunity, but they are also involved in regulating excessive immune responses and chronic inflammation. Evidence has emerged regarding roles for individual selenoproteins in regulating inflammation and immunity, and this has provided important insight into mechanisms by which Se influences these processes. Se deficiency has long been recognized to negatively impact immune cells during activation, differentiation, and proliferation. This is related to increased oxidative stress, but additional functions such as protein folding and calcium flux may also be impaired in immune cells under Se deficient conditions. Supplementing diets with above-adequate levels of Se can also impinge on immune cell function, with some types of inflammation and immunity particularly affected and sexually dimorphic effects of Se levels in some cases. In this comprehensivearticle, the roles of Se and individual selenoproteins in regulating immune cell signaling and function are discussed. Particular emphasis is given to how Se and selenoproteins are linked to redox signaling, oxidative burst, calcium flux, and the subsequent effector functions of immune cells. Data obtained from cell culture and animal models are reviewed and compared with those involving human physiology and pathophysiology, including the effects of Se levels on inflammatory or immune-related diseases including anti-viral immunity, autoimmunity, sepsis, allergic asthma, and chronic inflammatory disorders. Finally, the benefits and potential adverse effects of intervention with Se supplementation for various inflammatory or immune disorders are discussed. Antioxid. Redox Signal. 16, 705-743.

“…Because asthma involves increased levels of oxidative stress, Se intake has been hypothesized to play a role in the development and/or severity of this complex disease. However, descriptive studies in humans have produced conflicting results with some finding an association between low Se status and asthma (2)(3)(4)(5), and others failing to confirm this association (6)(7)(8). Dietary Se has even been found to be positively associated with severity of bronchial responsiveness (9).…”

mentioning

confidence: 99%

Selenium and asthma: a complex relationship

2008

Allergy

Descriptive studies in humans investigating the relationship between selenium (Se) status and asthma have presented inconsistent results. The concept of low Se status as a potential risk factor for increased prevalence or severity of asthma is based on the role that Se, through its incorporation into selenoproteins, plays as a potent antioxidant capable of augmenting the oxidative stress that accompanies asthma. However, Se intake also exerts a significant influence over immune responses. Thus, the dual effects of Se status on controlling oxidative stress in the lungs and regulating T helper 2 responses that drive allergic asthma, as well as which selenoproteins are key to regulating these processes, must be considered when attempting to decipher the relationship between this essential nutrient and complex allergic diseases such as asthma.