Vitamin D and Its Receptor Gene Polymorphisms in Lithuanian, Latvian and Taiwanese Patients With Atopic Dermatitis and Asthma
Study Purpose
The role of vitamin D is well known in calcium and phosphate homeostasis; however, in addition to traditional functions, vitamin D has an important role in pathogenesis of different allergic diseases, such as asthma, atopic dermatitis (AD), and food allergy. There are evidences that lower cord blood vitamin D status is observed in infants with eczema. More-over, vitamin D level is decreased in subjects with asthma. One of the most important functions of vitamin D is to modulate the immune system response, both innate and adaptive, by suppressing Th2-type response and increasing natural killer cells. Vitamin D induces a higher level of IL-10, which is known as anti-inflammatory cytokine. Other studies have shown that vitamin D contributes to the conversion of CD4+ T cells to T regulatory cells. Recent studies showed that higher serum 25-hydroxyvitamin D level was associated with a reduced risk of asthma exacerbation and hospitalization. Vitamin D can enhance dexamethasone-induced MAP kinase phosphatase-1 (MKP-1) expression in peripheral blood mononuclear cells. Experimental data suggest that vitamin D can potentially increase the therapeutic response to glucocorticoid and can be used as an add-on treatment in steroid-resistant asthmatics. Vitamin D stimulates the production and regulation of skin antimicrobial peptides, such as cathelicidins, which have both direct antimicrobial activity and induced host cellular response by triggering cytokine release. Recent evidence suggests that low blood vitamin D level is a risk factor for food allergy. Vitamin D acts by binding to the vitamin D receptors (VDRs), which are located in a variety of tissues. VDRs have been identified on nearly all cells of the immune system including T cells, B cells, neutrophils, macrophages, and dendritic cells (DCs). Vitamin D deficiency predisposes to gastrointestinal infections by changing gut micro-biota, which may promote the development of food allergy. However the detail mechanism how vitamin D affects or protects the development of allergic diseases is still unknown. Vitamin D level is determined by sun exposure. Due to the fact that Lithuania, Latvia and Taiwan are located in different latitudes of north hemisphere with markedly different sun exposure, in this Joint collaboration study between Taiwan, Lithuanian and Latvia, we are going to study, (1). Serum vitamin D level in children and adults with AD and/or asthma in Lithuania, Latvia and Taiwan. (2). VDRs genetic polymorphisms of AD and/or asthma in children and adults in Lithuania, Latvia and Taiwan. (3). Finally, we would like to explore the gut microbiome of patients with AD and/or asthma in Lithuanian, Latvian and Taiwanese children and adults; and to estimate possible relationship between gut microbiome and vitamin D level and VDRs genetic polymorphisms. We believe that this study will be the first which compares the populations with different geographical and ecological factors having the same allergic diseases. We hope that these results will provide the answer about the role of vitamin D in the prevention, or in the future, in treatment of allergic diseases.
Recruitment Criteria
Accepts Healthy Volunteers
Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms |
Unknown |
Study Type
An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes. An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes. Searching Both is inclusive of interventional and observational studies. |
Observational |
Eligible Ages | N/A - 60 Years |
Gender | All |
Trial Details
Trial ID:
This trial id was obtained from ClinicalTrials.gov, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries. |
NCT04354207 |
Phase
Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans. Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data. Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs. Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use. |
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Lead Sponsor
The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data. |
Lithuanian University of Health Sciences |
Principal Investigator
The person who is responsible for the scientific and technical direction of the entire clinical study. |
Brigita Sitkauskiene, Prof. |
Principal Investigator Affiliation | Lithuanian University of Health Sciences |
Agency Class
Category of organization(s) involved as sponsor (and collaborator) supporting the trial. |
Other |
Overall Status | Enrolling by invitation |
Countries | Lithuania |
Conditions
The disease, disorder, syndrome, illness, or injury that is being studied. |
Atopic Dermatitis, Asthma |
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