Polarization toward Th1-type response in active, but not in inactive, lupus inhibits late allergic rhinitis in lupus-prone female NZB×NZWF(1) mice

MicroRNA-345-5p acts as an anti-inflammatory regulator in experimental allergic rhinitis via the TLR4/NF-κB pathway

Allergic rhinitis (AR) is a common chronic condition characterized by inflammation of the nasal mucosa. The correlation of microRNAs (miRNAs) in AR has been highlighted particularly due to their roles in regulating inflammatory responses. The aim of this study was to explore the anti-inflammatory mechanism by which miR-345-5p regulates the toll-like receptor 4/nuclear factor-κB (TLR4/NF-κB) pathway in mice with AR. Initially, the putative miR-345-5p binding sites on the 3'untranslated region of TLR4 was predicted and verified. AR models were established using ovalbumin, after which the functional role of miR-345-5p in AR was determined using gain- and loss-of-function approaches. We found that miR-345-5p was poorly expressed in nasal mucosal tissues of mice with AR. Meanwhile, TLR4 expression and the TLR4/NF-κB pathway were identified to be promoted, which were then suppressed in the presence of overexpressed miR-345-5p. In addition, nasal epithelial cell apoptosis and fibrosis were inhibited in response to miR-345-5p overexpression and TLR4 silencing. Furthermore, miR-345-5p overexpression and TLR4 silencing were observed to decrease Th2 cells, expression of pro-inflammatory factors, but to increase Th1 cells and expression of anti-inflammatory factors. This study demonstrates an important role of miR-345-5p in alleviating the inflammatory response in mice with AR by inhibiting the TLR4/NF-κB pathway. Therefore, a better understanding of this process may aid in the development of novel therapeutic agents of AR.

Mahuang Fuzi Xixin Decoction Attenuates Th1 and Th2 Responses in the Treatment of Ovalbumin-Induced Allergic Inflammation in a Rat Model of Allergic Rhinitis

Allergic rhinitis (AR) is one of the most common allergic diseases, which adversely affect patients' quality of life. Mahuang Fuzi Xixin decoction (MFXD) has been widely used to treat AR in clinics in Asian countries. This study investigated the effect and possible therapeutic mechanisms of MFXD in the treatment of AR. A Wistar rat model of ovalbumin- (OVA-) induced AR was established and then treated with three doses of MFXD; AR symptoms, serum total immunoglobulin E, histamine, histopathological features, and release and expression of factors related to type 1 helper T (Th1) and type 2 helper T (Th2) responses were analyzed. Our study demonstrated that MFXD has a good therapeutic effect on OVA-induced allergic inflammation in an AR rat model as manifested in reduced frequencies of sneezing and nasal scratching and in reduced serum levels of total IgE and HIS. In addition, MFXD regulates imbalance in Th1/Th2 cells caused by AR by simultaneously attenuating Th1 and Th2 responses, such as by reducing the serum levels of IFN-γ and IL-4 and mRNA expression levels of IFN-γ, IL-4, GATA-3, and STAT-6. This study provided valuable information on the immunoregulatory effect of MFXD for the treatment of AR in future clinical studies.

The pathologic and clinical intersection of atopic and autoimmune disease

Hypersensitivity reactions of the immune system have been broadly categorized into the atopic and autoimmune depending on whether the antigen triggering the reaction is endogenous (or self) or exogenous, the types of cellular and humoral components involved, and the clinical symptoms. Research into the pathophysiology of the resultant disease states has focused on a dichotomy between Th1 and Th2 T helper lymphocytes thought to govern autoimmune and atopic disease, respectively. Recent discoveries, however, have served to dispute this paradigm and have provided additional insight into the roles of Th17 cells, B-lymphocytes and T regulatory cells as well as the considerable communication and commonalities between the complex signaling pathways. Furthermore, clinical studies have served to challenge the idea that the presence of atopy and autoimmunity are mutually exclusive states. Finally, application of recent approaches to treatment-biologic targeted therapy in autoimmunity and induction of immune tolerance in atopic disease--to both disease states have shown mixed but promising results.