Paljung-San, a traditional herbal medicine, attenuates benign prostatic hyperplasia in vitro and in vivo

Ethnopharmacological relevance: Paljung-san is a traditional herbal medicine used widely for the treatment of urogenital diseases in East Asia. However, scientific evidence of the efficacy of Paljung-san and its mechanisms of action against benign prostatic hyperplasia (BPH) is not clearly established. Aim of the study: We investigated the inhibitory effect of Paljung-san water extract (PSWE) and its mechanisms against BPH in vitro and in vivo. Materials and methods: Active compounds of PSWE were analyzed quantitatively by High-performance liquid chromatography (HPLC). For in vitro study, PSWE treated BPH-1 cells were used to perform western blot analysis, cell cycle analysis and enzyme-linked immunosorbent assay. For in vivo BPH model, male rats were subcutaneously injected with 10 mg/kg of testosterone propionate (TP) every day for four weeks. 200 and 500 mg/kg of PSWE was administrated daily by oral gavage with s.c. injection of TP, respectively. Results: HPLC revealed that PSWE contains 1.21, 1.18, 2.27, 3.56, 4.23, 3.00, 6.78, and 0.004 mg/g of gallic acid, 5-caffeoylquinic acid, chlorogenic acid, geniposide, liquiritin apioside, liquiritin, glycyrrhizin, and chrysophanol components, respectively. In human BPH-1 cells, PSWE treatment reduced cell proliferation through arresting the cell cycle in the DNA synthesis phase. Moreover, PSWE suppressed prostaglandin E-2 production with reduced cyclooxygenase-2 expression. In TP-induced BPH rat model, PSWE administration showed reduced prostate weights and dihydrotestosterone levels and led to a restoration of normal prostate morphology. PSWE also decreased TP-induced Ki-67 and cyclin D1 protein levels in the prostatic tissues. Decreased glutathione reductase activity and increased malondialdehyde levels in the BPH groups were reversed by PSWE administration. Conclusion: PSWE attenuates the progression of BPH through anti-proliferative, anti-inflammatory and antioxidant activities in vitro and in vivo. Therefore, these data provide the scientific evidence of pharmacological efficacy of PSWE against BPH.