Intervention mechanism of moxa-cone moxibustion at Shu- and Mu-acupoints on the expression of RORγt/Foxp3 in asthma mice: an analysis based on PI3K signaling pathway

Abstract

To explore the effect of moxa-cone moxibustion at "Feishu" (BL13) and "Zhongfu" (LU1) on the contents of related inflammatory factors in serum and bronchoalveolar lavage fluid (BALF), and the expression of phosphatidy-linositol-3-kinase (PI3K), retinoic acid related orphan receptor γt (RORγt) and fork/wing helix transcription factor 3 (Foxp3) in lung tissue in asthma mice. Sixty male Balb/c mice were divided into normal, model, LY294002 (an inhibitor of PI3K, LY), electroacupuncture (EA) and moxa-cone moxibustion (moxibustion) groups (n=12 in each group). The asthma model was established by intraperitoneal injection of ovalbumin sensitization. The mice in the LY group were injected with LY 294002 (7.5 mg/kg) via the tail vein. EA or moxa-cone moxibustion was applied at BL13 and LU1 in the EA or moxibustion group once daily for 2 weeks. The levels of immunoglobulin E (IgE), interleukin-4 (IL-4) and interferon-γ (IFN-γ) in serum and BALF were detected by enzyme-linked immunosorbent assay. The expressions of PI3K, RORγt and Foxp3 in lung tissue were detected by real-time fluorescent quantitative polymerase chain reaction (QRT PCR) and immunohistochemistry. Compared with the normal group, the levels of IgE and IL-4 in serum and BALF, the expressions of PI3K and RORγt mRNA and protein in lung tissue were significantly increased (P<0.01), while the levels of IFN-γ, and the expressions of Foxp3 mRNA and protein were significantly reduced (P<0.01) in the model group. Compared with the model group, the levels of IgE and IL-4 in serum and BALF, the expressions of PI3K and RORγt mRNA and protein in lung tissue were significantly decreased (P<0.01, P<0.05), and the levels of IFN-γ in serum and BALF, the expressions of Foxp3 mRNA and protein in lung tissue were significantly increased (P<0.01) in the LY, EA and moxibustion groups. Moxa cone moxibustion at Shu- and Mu-acupoints of the lung meridian can reduce airway inflammatory reaction and control asthma attacks in asthma mice, which is closely related to its effects in regulating the expressions of RORγt and Foxp3 through PI3K signaling pathway.