Qi-Gui-Sheng-Jiang-San Decoction Regulating Hypoxia Response Through Non-Oxygen-Dependent Pathway Improves Diabetic Kidney Disease: Coupling Network Pharmacology With Experimental Verification.

Background: Diabetic kidney disease (DKD) is a major global cause of end-stage renal disease. Emerging evidence suggests that hypoxia is a critical factor in the advancement of DKD. Traditional Chinese medicine (TCM) is an effective alternative therapy for DKD. The Qi-Gui-Sheng-Jiang-San (QGSJS) decoction is an effective formula for treating DKD clinically, and its mechanism may be related to regulating hypoxia response, necessitating further investigation and a thorough analysis of the underlying biological mechanisms. Methods: Initially, we employed network pharmacology methods to collect and screen the active constituents of the QGSJS decoction from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and relevant chemical databases. Subsequently, the targets of these active components were predicted via the PubChem and TCMSP databases, while relevant targets associated with DKD were sourced from GeneCards, OMIM, and DrugBank. In the second phase, we built a protein-protein interaction (PPI) network via the STRING database to identify core targets. This was followed by GO and KEGG enrichment analyses to assess if the QGSJS decoction's mechanisms of action are linked to hypoxic response regulation. Finally, in vivo experiments were performed to confirm the findings from the network pharmacology analysis and to comprehensively elucidate the QGSJS decoction's mechanisms of action. Results: The network pharmacology analysis revealed 57 active components in the QGSJS decoction, capable of influencing 72 targets associated with DKD. Quercetin, kaempferol, and isorhamnetin are likely to be the key constituents of the QGSJS decoction. The PPI network suggests that HIF1A serves as a hub gene, closely associated with IL6, NFKBIA, and VEGFA. Enrichment analysis indicates that the QGSJS decoction modulates the HIF-1 signaling pathway and impacts biological processes and molecular functions linked to HIF-1α. In vivo studies demonstrate the QGSJS decoction's renal protective properties, suppressing the expression of HIF-1α, p-STAT3, p-Akt, VEGF, VEGFR, p-NF-κB, and NOTCH1 in the kidneys without affecting PHD2. Conclusion: The QGSJS decoction primarily inhibits HIF-1α through non-oxygen-dependent pathways, mitigating damage related to abnormal hypoxic responses, which may be the main mechanism through which it protects the kidneys.