The Efficacy of Nigella Sativa in Children With House Dust Mite-Induced Respiratory Allergy Receiving Immunotherapy

Overview

An experimental study aims to investigate the efficacy of Nigella Sativa in children with house dust mite (HDM)-induced respiratory allergy receiving immunotherapy. This study observes symptom, medication, combine symptom-medication score, quality of life (QoL), skin prick test, IL-4, TGF-β, IL-10, IgG4 specific HDM, IgE Specific HDM, and IFN-γ as the outcome. This study will be done on 40 subjects (20 subjects in control group and 20 subjects in experimental group), in children diagnosed with house dust mite-induced respiratory allergy such as allergic rhinoconjunctivitis and/or asthma, with an age of 2 to 17 years old, receiving allergen specific immunotherapy, not having an autoimmune disease, malignancy, nor chronic respiratory infection at the beginning of study, and has an approval from their parents. In control group, subjects will receive allergen specific immunotherapy and standard pharmacotherapy for underlying diagnose. In experimental group, subjects will receive nigella sativa oil for 14 weeks, allergen specific immunotherapy, and standard pharmacotherapy for underlying diagnose. All subjects will observe for 14 weeks during build up phase of immunotherapy. They will be monitored regularly, since this study starts, at each week, and at the end of this study. The symptom, medication, and combine symptom-medication score will be calculated at every session of monitoring. Quality of life (QoL), skin prick test, IL-4, TGF-β, IL-10, IgG4 specific HDM, IgE Specific HDM, and IFN-γ will be collected at the beginning and the end of this study.

House dust mite (HDM) is one of allergen that often cause respiratory allergy. In chronic condition respiratory allergy can have an impact in growth and development as well as the quality of life of a child. Children that strongly sensitized to house dust mite have the high risk of asthma and allergic rhinitis. Study in urban areas in Indonesia found that the prevalence of sensitization to HDM is quite high in elementary school children, which is 28.6%. House dust mites have even become an allergen with the most sensitization in junior and senior high school children in urban areas in Indonesia with a prevalence of 62.5%. Avoidance of allergens is actually the key to successful treatment of allergic diseases, but so far there is no proven effective HDM avoidance method to completely eliminate the HDM exposure. House dust mites-specific allergen immunotherapy is a solution for causal therapy in HDM allergies, because HDM-specific allergen immunotherapy will stimulate the immune system to become tolerant to HDM. Although immunotherapy has been shown to be effective in inducing tolerance in children with house dust mite-induced respiratory allergy, this process takes time where its effects are generally seen when entering the maintenance phase. One strategy that has recently been developed to increase therapeutic efficacy in medical therapy, including in allergic diseases is Complementary and Alternative Medicine (CAM) which includes the use of natural ingredients (vitamins, herbs, supplements), acupuncture, physiotherapy and others. Nigella sativa also known as black cumin is one of the herbs that are widely studied as a complementary and alternative therapy to increase the efficacy of standard therapy for allergic diseases. Nigella sativa contain several active components that have antihistamine effect, antioxidant, anti-inflammatory, and immunomodulatory effects in both in vitro and in vivo models. The main active component of nigella sativa that provides an immunomodulatory effect is thymoquinone (TQ). Nigella sativa extract can affect the process of allergic disease in various mechanisms. The immunomodulating effects of nigella sativa will increase the number of regulatory T cells (Treg) in allergic children. Treg will produce interleukin (IL)-10 which will suppress the activation of T helper (Th)2 cells, in addition IL-10 and Transforming Growth Factor-β (TGF-β) will stimulate B cells to produce more Immunoglobulin (Ig)G4 Specific. Nigella sativa also has an antihistamine effect by increasing mast cell stabilization, than it will prevent mast cell degranulation. It also has the effect of non-selectively inhibiting histamine receptors. As an anti-inflammatory and immunomodulatory effect, nigella sativa inhibits the enzymes cyclooxygenase (COX) and lipoxygenase (LO) thereby inhibiting the formation of prostaglandins and leukotrienes which are important inflammatory mediators in the allergic process. Based on the data above, the addition of nigella sativa will be able to help accelerate and increase the efficacy of immunotherapy in children with house dust mite-induced respiratory allergy. However, scientifically consistent evidence is still needed, while until now clinical trial study on these is still limited.