Qiling Hushen Formula Ameliorates Type 2 Diabetic Kidney Disease via Gut‐Kidney Axis Restoration and TLR4/NF‐ κ B/NLRP3 Suppression

CONTEXT: Qiling Hushen Formula (QLHSF) has been widely used in clinical treatment for Type 2 diabetic kidney disease (T2DKD), yet its mechanism remains unclear. OBJECTIVE: This study is aimed at elucidating the protective effects and mechanisms of QLHSF on T2DKD mice. METHODS: Chemical components of QLHSF were analyzed via ultraperformance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS). After 6 weeks of QLHSF intervention in C57BL/KSJ db/db mice, urine and serum samples were collected to measure biochemical parameters, inflammatory cytokines, and lipopolysaccharide (LPS) levels. Renal and colonic tissues were sectioned and subjected to histopathological staining. To evaluate the diversity and abundance of the gut microbiota, its composition was determined through 16S rRNA gene sequencing. Expression levels of colonic tight junction proteins, along with key proteins involved in the renal TLR4/NF-κB signaling pathway and NLRP3 inflammasome activation, were measured. RESULTS: QLHSF decreased proteinuria and improved renal function in T2DKD mice. Renal pathological injuries and intestinal barrier destruction were also alleviated. Analysis of 16S rRNA sequencing data demonstrated that QLHSF significantly modulated the gut microbiota composition, enriching beneficial bacteria such as gBacteroides, gLachnospiraceaeNK4A136group, gAlistipes, gMuribaculum, gOdoribacter, and gLachnoclostridium. QLHSF treatment led to a reduction in serum LPS levels and inhibition of the renal TLR4/NF-κB/NLRP3 signaling pathway, leading to reduced inflammatory cytokine production. CONCLUSIONS: In T2DKD mice, QLHSF ameliorated proteinuria and renal injury through modulation of the gut microbiota, preservation of intestinal barrier integrity, and inhibition of the renal TLR4/NF-κB/NLRP3 pathway. These findings elucidate the pharmacological mechanism of QLHSF and provide strong experimental support for its clinical application in the treatment of T2DKD.