Potential Role of AGEs in Paediatric Allergies
Condition: Allergy
MeSH terms: Hypersensitivity
Study type: Observational

Summary: 
      Food allergy (FA) is "an adverse health effect arising from a specific immune response that
      occurs reproducibly" according to the 2010 National Institute of Allergy and Infectious
      Diseases, National Institutes of Health (NIAID/NIH)-supported Guidelines for the Diagnosis
      and Management of Food Allergy in the United States (Boyce et al. 2010). Studies have
      suggested that the natural history of FA has changed during the last two decades, with a
      dramatic rise in the prevalence, severity of clinical manifestations, and risk of persistence
      into later ages, leading to an increase in hospital admissions, medical visits, treatments,
      and burden of care on families and to an important economic impact, with significant direct
      costs for the families and healthcare system (Skripak et al. 2007; McBride et al. 2012; Gupta
      et al. 2013). The development of FA might be influenced by genetics, environment, and
      genome-environment interactions, leading to immune system dysfunction, mediated at least in
      part by epigenetic mechanisms (Berni Canani et al. 2015; Paparo et al. 2018). Many factors
      have been postulated to contribute to the onset of FA. Among dietary factors, it has been
      hypothesized that advanced glycation endproducts (AGEs), present at high level in junk food,
      could be involved in FA pathogenesis. AGEs are a heterogeneous group of compounds deriving
      from a non-enzymatic reaction between reducing sugars and free amino groups of proteins,
      lipids, or nucleic acids. This reaction is also known as the Maillard or browning reaction.
      The formation of AGEs is a part of normal metabolism, but if excessively high levels of AGEs
      are reached in tissues and the circulation they can become pathogenic. AGEs are naturally
      present in uncooked animal-derived foods, and cooking results in the formation of new AGEs
      within these foods. Consumption of AGE-rich diets is associated with elevated circulating and
      tissue AGEs and an increase of their pro-inflammatory and pro-oxidant effects. On the other
      hand, restriction of AGEs prevents inflammation. AGEs not only exert their deleterious
      actions due to their biological properties, but also through their interaction with specific
      receptors (RAGE). AGEs are able to activate mast cells and induces a chronic inflammatory
      state that promotes a Th2 type response. The aim of this study is to evaluate the AGEs levels
      in FA children compared with healthy controls and subjects with other allergic diseases.
    

Detailed description: 
      The study is designed to evaluate the AGEs concentration in allergic children compared with
      healthy controls and to investigate the potential role of AGEs in FA pathogenesis. First, the
      investigators will define subcutaneous AGEs levels in children affected by allergy, comparing
      to non-allergy children AGEs levels. Subsequently, the investigators will investigate the
      possible correlation with dietary habits and the potential effects of AGEs on gut barrier
      components and on non-immune and immune mechanisms in experimental models.
    

Intervention name(s): advanced glycation endproducts reader
Intervention type(s): Diagnostic Test
Intervention description(s): advanced glycation endproducts reader
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Children with confirmed diagnosis of allergy and healthy controls consecutively observed at
        our tertiary center for pediatric allergy will be evaluated for inclusion in the study.
        Only subjects who will meet the inclusion criteria will be invited to participate in the
        study. Anamnestic, demographic, anthropometric, and clinical data, as well as information
        on use of drugs, pre-, pro- or symbiotic products will be collected. Also dietary habits
        will be evaluated, particularly number, place and time of meals, special diets or
        elimination diets, frequency of consumption of cereals and derivatives, meat products,
        fish, eggs, dairy products, fruit and vegetables, legumes, sweets, sweetened beverages and
        possibly alcoholic drinks and the corresponding cooking methods.