Point application therapy targeting Feishu, Pishu and Shenshu attenuates asthma by suppressing autophagy and the AMPK-mTOR signalling pathway.

Abstract

Objective: In traditional Chinese medicine, asthma is associated with deficiencies in Lung Qi, Spleen Qi, and Kidney Qi. This study investigated the therapeutic mechanism of point application therapy focusing on the acupoints Feishu (BL13), Pishu (BL20), and Shenshu (BL23) for asthma treatment.

Methods: An asthma model was established in Wistar rats via intraperitoneal ovalbumin injection combined with nebulization. Therapeutic ointments were prepared using white mustard seed, Yanhusuo, Gansui and Asarum sieboldii, which were applied topically to the Feishu (BL13), Pishu (BL20) and Shenshu (BL23) acupoints. To examine the mechanistic basis, the AMPK inhibitor dorsomorphin (compound C, CC) was employed. We subsequently measured inflammatory factor levels in rat serum and bronchoalveolar lavage fluid, quantified AMPK/mTOR pathway-related protein expression, and assessed pulmonary inflammation alongside collagen deposition in airway mucosa.

Results: The point application therapy significantly ameliorated asthma symptoms and reduced levels of inflammatory factors, including interleukin (IL)-6 and IL-1β, in both serum and bronchoalveolar lavage fluid. The treatment additionally decreased expression levels of mTOR, LC3, NF-κB and TGF-β1 while increasing AMPK content. Histological examination revealed reduced inflammatory cell infiltration and diminished collagen deposition in both lung and airway tissues. Crucially, administration of the AMPK inhibitor dorsomorphin substantially attenuated the therapeutic efficacy of point application therapy in asthmatic rats.

Conclusions: Point application therapy targeting Feishu, Pishu and Shenshu acupoints inhibits autophagy in airway and lung tissues in asthma. These therapeutic effects are mediated, at least partially, through the AMPK/mTOR pathway.