Effect of acupuncture on serum levels of hypothalamic-pituitary-adrenal axis related hormones and immune factors in rats with allergic rhinitis.

Objective: To explore the correlation between acupuncture treatment for allergic rhinitis (AR) and hypothalamic-pituitary-adrenal (HPA) axis regulation by investigating changes in serum immune factors, HPA axis-associated hormone levels, activation levels of paraventricular nucleus (PVN) neurons, and the severity of nasal mucosal lesions, in rats with AR before and after acupuncture treatment.

Methods: After establishing the AR rat model, ovalbumin was administered vianasal drip to all groups except the blank control. Each group received continuous treatment for 14 d: the acupuncture, acupuncture + RU-486 (mifepristone), and RU-486 groups received acupuncture only, RU486 intraperitoneal injection and acupuncture, and RU-486 intraperitoneal injection only, respectively. Following the intervention period, behavioral scoring was performed on all AR rats, and peripheral blood, nasal mucosa samples, and brains tissue (containing PVN region) were obtained following euthanization. Interleukin (IL-4, IL-5, IL-13), interferon gamma (IFN-γ), corticosterone (CORT), and corticotrophin-releasing hormone (CRH) levels were evaluated in peripheral blood samples. Adrenocorticotropic hormone (ACTH) levels were determined using an enzyme-linked immunoassay assay, and hematoxylin and eosin staining was performed on the nasal mucosa samples. The expression levels of c-Fos in PVN neurons following acupuncture treatment were evaluated by immunofluorescent staining.

Results: Following the intervention period, the behavioral scores for the blank control group were lower than those of other groups (P < 0.05), while the acupuncture group scores were lower than those in the model control, acupuncture + RU486, and RU486 groups (P < 0.05). The blank control group had lower serum IL-4, IL-5, and IL-13 levels than those in the other groups (P < 0.05). The acupuncture group had lower serum IL-4, IL-5, and IL-13 levels than those in the model control, acupuncture + RU486, and RU486 groups (P < 0.05). The blank control group had the highest serum IFN-γ levels among all groups, followed by the acupuncture group. The serum CORT, CRH, and ACTH levels in the blank control group were lower than those in the remaining groups (P < 0.05). These biomarker levels were also lower in the acupuncture group than those in the model control, acupuncture + RU486, and RU486 groups (P < 0.05). Compared with model, rats in the acupuncture group exhibited an increased c-Fos expression in PVN neurons.

Conclusion: Acupuncture can alleviate AR symptoms and regulate serum inflammatory factor levels and HPA axis-related hormones in AR rats. Moreover, these effects are inhibited by glucocorticoid antagonists, suggesting that acupuncture may regulate AR symptoms through HPA axis regulation.