The bioactive alkaloids identified from Cortex Phellodendri ameliorate benign prostatic hyperplasia via LOX-5/COX-2 pathways.

Abstract Background The bioactive alkaloids identified from Cortex Phellodendri (CP) were highly effective in treating rats with benign prostatic hyperplasia (BPH). Specifically, lipoxygenase-5 (LOX-5) and cyclooxygenase-2 (COX-2) were identified as two primary targets for alleviating inflammation in BPH rats. However, it remains unknown whether the alkaloid components in CP can interact with the two target proteins. Purpose To further identify bioactive alkaloids targeting LOX/COX pathways. Methods An affinity-ultrafiltration mass spectrometry approach was employed to screen dual-target LOX-5/COX-2 ligands from alkaloid extract. The structures of bioactive alkaloids were characterized by high-resolution Fourier transform ion cyclotron resonance mass spectrometry. To understand the molecular mechanisms underlying the effects of bioactive alkaloids, the expression levels of LOX-5 and COX-2 in BPH model rats were investigated at both protein and mRNA levels. The LOX-5/COX-2 enzymes activity experiments and molecular docking analysis were performed to fully evaluate the interactions between bioactive alkaloids and LOX-5/COX-2. Results After comprehensive analysis, the results showed that bioactive alkaloids could suppress the expression of LOX-5 and COX-2 simultaneously to exert an anti-inflammatory effect on the progression of BPH. In addition, the screened protoberberine, demethyleneberberine was found to exhibit prominent inhibitory activities against both LOX-5 and COX-2 enzymes, palmatine and berberine with moderate inhibitory activities. Molecular docking analysis confirmed that demethyleneberberine could interact well with LOX-5/COX-2. Conclusion This study is the first to explore the inhibitory effects of bioactive alkaloids from CP on LOX-5 and COX-2 activities in BPH rats. Our findings demonstrate that the bioactive alkaloids from CP can ameliorate BPH via dual LOX-5/COX-2 pathways, which serves as an efficient approach for the discovery of novel drug leads from natural products with reduced side effects.