Duhuo Jisheng decoction alleviates intervertebral disc degeneration by inhibiting nucleus pulposus cell pyroptosis via gallic acid-mediated downregulation of HIF-1α

Ethnopharmacological relevance: Duhuo Jisheng decoction (DHJS) is a traditional Chinese medicinal formula used to treat chronic low back pain related to intervertebral disc degeneration (IVDD). However, its bioactive constituents and mechanisms of action remain unclear.

Aim of the study: To explore the therapeutic mechanisms of DHJS in IVDD.

Material and methods: The bioactive constituents of DHJS were identified using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC‒QE‒MS) and network pharmacology analysis. We established an in-vitro TBHP-induced degenerative nucleus pulposus cells (NPCs) model to assess cell morphology, proliferation, Apoptosis, Reactive Oxygen Species (ROS) production, mitochondrial membrane potential, and expression of oxidative stress- and pyroptosis-related proteins (NLRP3, Caspase-1, and GSDMD). The relationship between Gallic Acid (GA) and HIF-1α was validated using HIF-1α overexpression lentivirus (OE-HIF-1α) and MitoTempo (MT). An in vivo IVDD rat model was constructed by systemic administration of GA via oral gavage and local intradiscal injection of an adeno-associated virus (AAV) vector to overexpress HIF-1α. Intervertebral disc tissues were analyzed via Hematoxylin and Eosin/Safranin O-Fast Green staining, immunohistochemistry, and histological scoring.

Results: UHPLC-QE-MS and network pharmacology analyses identified GA as an active component, with HIF-1α as the predicted primary target. In vitro, tert-butyl hydroperoxide (TBHP)-induced NPCs degeneration (swelling, Apoptosis, ROS accumulation, mitochondrial dysfunction, and pyroptosis-related protein upregulation). GA reversed these changes by reducing ROS levels, restoring mitochondrial potential, upregulating antioxidant proteins, and downregulating pyroptosis-related proteins. OE-HIF-1α abrogated GA's effects, whereas Mito Tempo partially reversed these effects. GA improved IVDD in rats, which was reversed by HIF-1α overexpression.

Conclusions: GA, an active component of DHJS, alleviates IVDD by targeting HIF-1α to inhibit oxidative stress-induced Pyroptosis in NPCs. Its therapeutic efficacy is synergistically enhanced by Other key components, such as paeoniflorin and naringin, validating the holistic principles of TCM formulations. This study provides a natural drug candidate and theoretical basis for alleviating clinical LBP.

Gallic acid; Intervertebral disc degeneration; Network pharmacology analysis; Traditional Chinese medicine.