Antiallergic Effects of Callerya atropurpurea Extract In Vitro and in an In Vivo Atopic Dermatitis Model

(1) Background: Callerya atropurpurea is found in Laos, Thailand, and Vietnam. Although the anti-inflammatory action of C. atropurpurea has been investigated, the functions of this plant in allergic responses are not understood. Here, we explored the antiallergic mechanism of C. atropurpurea ethanol extract (Ca-EE) using in vitro assays and an in vivo atopic model. (2) Methods: The constituents of Ca-EE were analyzed using GC/MS. Inhibition of lipoxygenase and β-hexosaminidase activity was examined, and the expression of inflammatory genes was measured by quantitative real-time PCR. The regulatory roles of Ca-EE in IgE/FcεRI signaling were examined by Western blotting. The DNCB-induced atopic dermatitis mouse model was performed with histological analysis. (3) Results: Ca-EE comprised cis-raphasatin, lupeol, some sugars, and fatty acids. In RBL-2H3 cells, treatment with Ca-EE significantly reduced the activities of lipoxygenase and β-hexosaminidase, as well as cytokine gene expression. IgE-mediated signaling was downregulated by blocking Lyn kinases. Moreover, Ca-EE effectively inhibited allergic symptoms in the DNCB-induced atopic dermatitis model without toxicity. (4) Conclusions: Ca-EE displayed antiallergic activities through regulating IgE/Lyn signaling in RBL-2H3 cells and a contact dermatitis model. These results indicate that Ca-EE could be effective for allergic disease treatment.

Callerya atropurpurea suppresses inflammation in vitro and ameliorates gastric injury as well as septic shock in vivo via TLR4/MyD88-dependent cascade

BACKGROUND

Callerya atropurpurea is a traditional plant in a tropical zone discovered to have anti-inflammatory functions.

PURPOSE

we want to investigate the mechanism related to anti-inflammation of C. atropurpurea ethanol extract (Ca-EE) both in vitro and in vivo.

STUDY DESIGN

Murine macrophage cells and mouse models for gastritis and septic shock were conducted to evaluate the abilities of Ca-EE in anti-inflammation.

METHODS

Ca-EE was tested by HPLC and LC-MS/MS. NO outcome was checked by Griess reagent test. Cell viabilities were evaluated using MTT assay. Inflammatory cytokines were determined via RT-PCR and ELISA. The mechanism of Ca-EE in anti-inflammation was investigated by luciferase reporter gene assay and immunoblot in transcription level and protein level respectively. Gastric injury and septic shock administrated with Ca-EE were studied by H&E, PCR, and immunoblot.

RESULTS

Ca-EE significantly decreased LPS-induced NO production, but hardly stimulated the expression of NO itself. It not only showed no cytotoxicity, but also protected cells from LPS damage. Moreover, Ca-EE decreased TLR4 expression, altered MyD88 recruitment and TRAF6, and suppressed the phospho-Src/PI3K/AKT. Ca-EE inhibited downstream signaling P38, JNK and NF-κB. Finally, Ca-EE alleviated HCl/EtOH-induced gastritis and LPS/poly (I:C)-induced septic shock through the previously mentioned signaling cascades.

CONCLUSION

Ca-EE exhibited an integrated and promising mechanism against TLR4-related inflammation, which shows potential for treating gastritis, septic shock, and other inflammatory diseases.