[Mechanism of thermo-sensitive moxibustion intervention in regulating Th17/Treg immune imbalance in the rat model of allergic rhinitis].

Abstract

Objectives: To investigate the effects of thermo-sensitive moxibustion on helper T cells(Th)17/regulatory T cells(Treg) immune imbalance and related cytokines in the rat model of allergic rhinitis (AR).

Methods: Thirty 8-week-old SD rats were randomly divided into a blank group (n=6), a model group (n=6), a western medicine group (n=6), and a moxibustion group (n=12). AR model was established by intraperitoneal injection of ovalbumin and aluminium hydroxide suspension for 14 d followed by intranasal administration of 20 μL of 12% ovalbumin for 10 days. After successful modeling, rats in the western medicine group received 8 μL of fluticasone propionate intranasally for 21 days;the moxibustion group was divided into a thermo-sensitive moxibustion group(n=4) and a traditional moxibustion group(n=4) based on whether the increase in tail temperature detected by an infrared thermal imager was greater than 1 °C. Both moxibustion groups received moxibustion on "Feishu"(BL13) for 40 minutes, for 21 days. After the intervention, HE staining was used to observe the morphological changes of the nasal mucosa;ELISA was performed to measure serum interleukin(IL)-17A, IL-10, and transforming growth factor(TGF)-β1 contents;and immunohistochemical staining was used to observe the expression of IL-17A, retinoid-related orphan nuclear receptor γt(RORγt), IL-10, TGF-β1, and forkheadbox protein 3(FOXP3) in the nasal mucosa;flow cytometry was used to detect the percentage of Th17 and Treg in peripheral blood.

Results: Compared with the blank group, rats in the model group displayed swelling and deformation of the nasal mucosa, significant eosinophil infiltration, and increased serum IL-17A contents along with increased expression of IL-17A and RORγt in the nasal mucosa, as well as a significant rise in peripheral blood Th17 percentage (P<0.001, P<0.05);while serum IL-10 and TGF-β1 contents, along with FOXP3, IL-10, and TGF-β1 expression in the nasal mucosa and peripheral blood Treg percentage were significantly reduced (P<0.05, P<0.001). Compared with the model group, no significant thickening or eosinophil infiltration was found in the nasal mucosa of the western medicine, traditional moxibustion, or thermo-sensitive moxibustion groups, with improvements of the above indicators observed in all groups to varying extents (P<0.001, P<0.01, P<0.05). Compared with the thermo-sensitive moxibustion group, the western medicine group showed decreased expression of FOXP3 in the nasal mucosa (P<0.05), while serum IL-17A contents and nasal mucosal TGF-β1, RORγt, and IL-17A expressions were increased (P<0.001, P<0.01, P<0.05), with an increase in peripheral blood Th17 percentage(P<0.01) and a decrease in Treg cells (P<0.01);Traditional moxibustion group showed significantly reduced levels of serum IL-10 content and IL-10 expression in the nasal mucosa (P<0.001), along with higher expression of RORγt and IL-17A (P<0.001, P<0.01). Compared with the traditional moxibustion group and westernmedicine group, the thermo-sensitive moxibustion group had milder nasal mucosa swelling, less eosinophil infiltration.

Conclusions: Thermo-sensitive moxibustion may alleviate allergic rhinitis by regulating Th17/Treg immune balance and related cytokines.