Rehmannioside A Inhibits TRAF6/MAPK Pathway and Improves Psoriasis by Interfering with the Interaction of HaCaT Cells with IL-17A

Objective

As a common chronic inflammatory skin disease, psoriasis seriously affects the physical health and psychological well-being of patients. Various clinical treatments for psoriasis have their own drawbacks, so it is important to find effective and safe drugs. Rehmannioside A (ReA) has anti-inflammatory properties and is the main active ingredient in Fuzhengzhiyanghefuzhiyang decoction (FZHFZY), an herbal compound for the treatment of psoriasis. But no studies have been conducted to determine whether ReA alone can treat psoriasis. Therefore, this study was designed to investigate the effect of ReA in the treatment of psoriasis and its potential mechanism of action.

Methods

HaCaT cells were treated with ReA and IL-17A alone for 24 h and 48 h, and the most effective concentrations of ReA and interleukin (IL)-17A were found at 25 μg/mL and 100 ng/mL, respectively. A psoriasis cell model was constructed by stimulating HaCaT cells with IL-17A, followed by intervention with ReA. Cell viability and cell cycle distribution were measured by MTT assay and flow cytometry. The expression levels of keratin family members and chemokines were detected by real-time quantitative PCR (RT-qPCR), the levels of pro-inflammatory cytokines by enzyme-linked immunosorbent assay (ELISA), and key proteins of TRAF6/MAPK signaling pathway by Western blot.

Results

ReA weaken cell viability, down-regulate the expression of keratin family members (KRT6 and KRT17), restore cell cycle distribution to normal distribution, inhibit the release of pro-inflammatory cytokines (IL-6, IL-8 and IL-1β) and lower the expression of chemokines (S100A7, S100A9 and CXCL2) by interfering with the interaction between HaCaT cells and IL-17A. Thus, it exerts an anti-psoriatic effect by reducing the inflammatory response and inhibiting abnormal proliferation of HaCaT cells. Mechanistically, ReA inhibited the TRAF6/MAPK signaling pathway activated by IL-17A stimulation in HaCaT cells.

Conclusion

ReA has in vitro anti-psoriatic effects and may be a new therapeutic agent for psoriasis.

Reactive Arthritis in Children: Case report and Narrative Review and Proposed therapy

Reactive arthritis is an acute inflammatory aseptic arthritis that is preceded by an infectious process in genetically predisposed individuals. It has been associated with gastrointestinal or genitourinary infection. Reactive arthritis is rare in children. In this review, we present two index cases that need biologic treatment followed by a thorough review of reactive arthritis in children and adolescents with proposed treatment algorithm.

Reactive arthritis and undifferentiated peripheral spondyloarthritis share human leucocyte antigen B27 subtypes and serum and synovial fluid cytokine profiles

OBJECTIVES

Peripheral SpA (pSpA) is comprised of ReA, PsA, enteritis-associated arthritis and undifferentiated pSpA (upSpA). ReA and upSpA share T cell oligotypes and metabolomics in serum and SF. We investigated HLA-B27 subtypes and cytokines in serum and SF that were compared between ReA and upSpA.

METHODS

ReA and upSpA were compared in two cohorts. In cohort I (44 ReA and 56 upSpA), HLA-B27 subtyping was carried out. In cohort II (17 ReA and 21 upSpA), serum and SF cytokines were compared using a multiplex cytokine bead assay (27 cytokines). A total of 28 healthy controls with similar age and sex to cohort II were included for comparison of serum cytokine levels.

RESULTS

In cohort I, HLA-B27 was positive in 81.8% (36/44) of ReA and 85.71% (48/56) of upSpA patients. HLA-B27 typing was successful in 70 patients (30 ReA and 40 uSpA). HLA-B*2705 was the most common, followed by HLA-B*2704 and HLA-B*2707. Frequencies were the same between ReA and upSpA. In cohort II, 14 cytokines were detectable in the serum of patients. The levels of eight cytokines were higher than in the controls. The cytokine levels of ReA and upSpA were similar. Sixteen cytokines were detectable in the SF of patients. There was no statistical difference in the levels between ReA and upSpA. The cytokine profiles in sera and SF were also similar among HLA-B27-positive and negative patients.

CONCLUSION

ReA and upSpA have similar HLA-B27 subtype associations and similar cytokine profiles. They should be considered as a single entity during studies as well as clinical management.