Exploring the anti-fibrotic potential of gramine in a UUO-induced rat model of chronic kidney disease: A network pharmacology and molecular docking approach with experimental validation.

Abstract

ETHNOPHARMACOLOGICAL RELEVANCE: Gramine, an indole alkaloid derived from Arundo donax L., holds ethnopharmacological significance in traditional Ayurvedic medicine for treating urinary disorders. These ethnomedical insights encourage scientific exploration of gramine's potential role in renal pathologies, particularly fibrosis associated with chronic kidney disease (CKD), a steadily advancing condition impacting ∼850 million people globally, with understudied and inadequate therapies. AIM OF THE STUDY: To investigate gramine's anti-fibrotic potential in CKD using an integrative strategy, combining ADMET profiling, network pharmacology, molecular docking, transcriptomic correlation and experimental validation using a unilateral ureteral obstruction (UUO) model of CKD. MATERIALS AND METHODS: ADMET properties and target predictions for gramine were identified using predictive modelling tools, while CKD-related targets were retrieved from GeneCards. Protein-protein interaction and pathway enrichment analyses were performed using STRING and DAVID, followed by molecular docking in PyRx and transcriptomic correlation in Nephroseq. For in-vivo evaluation, rats underwent UUO surgery and received gramine (27.5 and 55 mg/kg, p.o.) for 21 days. Therapeutic outcomes were measured through kidney function tests, histopathology, ELISA, immunohistochemistry, and immunoblotting. RESULTS: Gramine exhibited favourable ADMET characteristics and was predicted to target 123 CKD-related proteins. Docking revealed strong binding affinity with key regulatory hubs HDAC2, NFKB1, and MAPK14, which are overexpressed in CKD tissues. In the UUO model, gramine preserved kidney function and histology by attenuating renal fibrosis associated with extracellular matrix (ECM) deposition and epithelial-mesenchymal transition (EMT). Protein-level analysis indicated downregulation of HDAC2, p-NF-κB, p-MAPK14, and TGF-β1, which are associated with fibrosis and inflammation, while restoring the antioxidant protein Nrf2, suggesting modulation of fibrogenic and inflammation-related pathways. CONCLUSION: Gramine mitigates UUO-induced renal fibrosis by modulating ECM/EMT-associated fibrogenic and inflammation-related pathways, primarily through MAPK14, NF-κB, and HDAC2, positioning it as a promising multi-target therapeutic candidate against CKD-associated fibrosis.