Vitamin D constrains inflammation by modulating the expression of key genes on Chr17q12-21.1.

Vitamin D possesses immunomodulatory functions and vitamin D deficiency has been associated with the rise in chronic inflammatory diseases, including asthma (Litonjua and Weiss, 2007). Vitamin D supplementation studies do not provide insight into the molecular genetic mechanisms of vitamin D-mediated immunoregulation. Here, we provide evidence for vitamin D regulation of two human chromosomal loci, Chr17q12-21.1 and Chr17q21.2, reliably associated with autoimmune and chronic inflammatory diseases. We demonstrate increased vitamin D receptor (Vdr) expression in mouse lung CD4+ Th2 cells, differential expression of Chr17q12-21.1 and Chr17q21.2 genes in Th2 cells based on vitamin D status and identify the IL-2/Stat5 pathway as a target of vitamin D signaling. Vitamin D deficiency caused severe lung inflammation after allergen challenge in mice that was prevented by long-term prenatal vitamin D supplementation. Mechanistically, vitamin D induced the expression of the Ikzf3-encoded protein Aiolos to suppress IL-2 signaling and ameliorate cytokine production in Th2 cells. These translational findings demonstrate mechanisms for the immune protective effect of vitamin D in allergic lung inflammation with a strong molecular genetic link to the regulation of both Chr17q12-21.1 and Chr17q21.2 genes and suggest further functional studies and interventional strategies for long-term prevention of asthma and other autoimmune disorders.

A plant proteinase inhibitor from Enterolobium contortisiliquum attenuates airway hyperresponsiveness, inflammation and remodeling in a mouse model of asthma.

INTRODUCTION: Proteinase inhibitors have been associated with anti-inflammatory and antioxidant activities and may represent a potential therapeutic treatment for asthma. PURPOSE: The aim of the present study was to evaluate the effects of Enterolobium contortisiliquum trypsin inhibitor (EcTI) on pulmonary mechanical function, eosinophilic recruitment, inflammatory cytokines, remodeling and oxidative stress in an experimental model of chronic allergic pulmonary inflammation. METHODS: BALB/c mice were divided into 4 groups: C (saline i.p and inhalations with saline), OVA (ovalbumin i.p and inhalations with ovalbumin); C+EC (saline i.p, inhalations with s aline and treatment with EcTI); OVA+EC (ovalbumin i.p, inhalations with ovalbumin and treatment with EcTI). On day 29, we performed the following tests: resistance (Rrs) and elastance (Ers) of the respiratory system; (b) quantify eosinophils, 8-ISO-PGF2α, collagen and elastic fiber volume fractions; (c) IFN-γ, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-ß, iNOS and p65-NFκB-positive cells in the airway and alveolar walls. RESULTS: In OVA+EC group, there was an attenuation of the Rrs and Ers, reduction of eosinophils, IL-4, IL-5, IL-13, IFN-γ, iNOS and p65-NFκB-positive cells compared to OVA group. The 8-ISO-PGF2α, elastic and collagen fibers volume fractions as well as the positive cells for MMP-9, TIMP-1 and TGF-ß positive cells were decreased in OVA+EC compared to the OVA group. CONCLUSION: EcTI attenuates bronchial hyperresponsiveness, inflammation, remodeling and oxidative stress activation in this experimental mouse model of asthma.