Optimized Aqueous Sedimentation for Methoxyflavone Enrichment from Kaempferia parviflora and Its Mechanistic Suppression of Benign Prostatic Hyperplasia via TGF-β/SMAD/ERK Signaling.

In benign prostatic hyperplasia (BPH), the activation of transforming growth factor-beta (TGF-β) signaling pathways triggers the proliferation of prostate stromal cells. In traditional Thai medicine, the rhizome of Kaempferia parviflora (KP) Wall. ex Baker (Zingiberaceae) has been applied to manage urinary symptoms related to BPH. Among the bioactive compounds found in KP extracts, the high abundance of methoxyflavones (MFs) has attracted attention. The binding affinities of MFs to the TGF-β1 receptor have been explored using molecular docking and molecular dynamics simulations. The sedimentation technique has successfully enriched MFs from KP extract, and 5,7-dimethoxyflavone (5,7-DMF) was used for standardizing both the KP extract and the enriched MFs. Investigating the standardization of KP extract and enriched MFs for their anti-BPH activity could provide scientific support for the therapeutic use of KP in treating BPH. The expression of proliferating cell nuclear antigen (PCNA) protein was reduced in both the enriched MFs and the standardized KP extract, which also arrested the cell cycle at the S phase through the TGF-β-mediated SMAD2/3 and ERK1/2 pathways. The enriched MFs exhibited greater potency in inhibiting cell proliferation compared to the KP extract. In conclusion, the sedimentation method is effective for scaling up the production of enriched MFs from the KP extract. This process yields a higher quantity of MFs with enhanced potency, requiring a smaller amount for treating BPH compared to conventional extraction methods for KP extract.