Albizzia julibrissin Suppresses Testosterone-induced Benign Prostatic Hyperplasia by Regulating 5α-Reductase Type 2 – Androgen Receptor Pathway

Albizzia julibrissin (AJ) is an herbal medicine that shows low toxicity, promotes promoting blood circulation and mitigates the inflammation and has mild side effects. Benign prostate hyperplasia (BPH) is one of the most common diseases that occurs in older males and often results in lower urinary tract symptoms. This study was conducted to evaluate the protective effect of AJ against BPH using LNCaP cells and Sprague Dawley rats treated with testosterone. Treatment with AJ extract reduced the expression of androgen receptor (AR) and prostate-specific antigen (PSA) in vitro. In vivo, rats were divided into 6 groups: 1 (Normal Control); 2 (Testosterone propionate (TP) alone); 3 (TP + finasteride); 4 (TP + AJ 10 mg/kg); 5 (TP + AJ 50 mg/kg); 6 (TP + AJ 300 mg/kg). The groups treated with AJ showed reduced the relative prostate weights and BPH-related proteins were altered, with decreased AR, PSA and proliferating cell nuclear antigen (PCNA) observed by western blot. Histopathological analysis revealed the therapeutic effect of AJ, with a decreased thickness of epithelial cells and reduced level of PCNA and 5α-reductase type 2. These results suggest that AJ extract could ameliorate testosterone-induced benign prostatic hyperplasia.

Murrayafoline A Induces a G0/G1-Phase Arrest in Platelet-Derived Growth Factor-Stimulated Vascular Smooth Muscle Cells

The increased potential for vascular smooth muscle cell (VSMC) growth is a key abnormality in the development of atherosclerosis and post-angioplasty restenosis. Abnormally high activity of platelet-derived growth factor (PDGF) is believed to play a central role in the etiology of these pathophysiological situations. Here, we investigated the anti-proliferative effects and possible mechanism(s) of murrayafoline A, a carbazole alkaloid isolated from Glycosmis stenocarpa Guillamin (Rutaceae), on PDGF-BB-stimulated VSMCs. Murrayafoline A inhibited the PDGF-BB-stimulated proliferation of VSMCs in a concentration-dependent manner, as measured using a non-radioactive colorimetric WST-1 assay and direct cell counting. Furthermore, murrayafoline A suppressed the PDGF-BB-stimulated progression through G0/G1 to S phase of the cell cycle, as measured by [3H]-thymidine incorporation assay and cell cycle progression analysis. This anti-proliferative action of murrayafoline A, arresting cell cycle progression at G0/G1 phase in PDGF-BB-stimulated VSMCs, was mediated via down-regulation of the expression of cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, and proliferating cell nuclear antigen (PCNA), and the phosphorylation of retinoblastoma protein (pRb). These results indicate that murrayafoline A may be useful in preventing the progression of vascular complications such as restenosis after percutaneous transluminal coronary angioplasty and atherosclerosis.

5,8-Dimethoxy-2-Nonylamino-Naphthalene-1,4-Dione Inhibits Vascular Smooth Muscle Cell Proliferation by Blocking Autophosphorylation of PDGF-Receptor beta

As the abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a critical role in the development of atherosclerosis and vascular restenosis, a candidate drug with antiproliferative properties is needed. We investigated the antiproliferative action and underlying mechanism of a newly synthesized naphthoquinone derivative, 5,8-dimethoxy-2-nonylamino-naphthalene-1,4-dione (2-nonylamino-DMNQ), using VSMCs treated with platelet-derived growth factor (PDGF). 2-Nonylamino-DMNQ inhibited proliferation and cell number of VSMCs induced by PDGF, but not epidermal growth factor (EGF), in a concentration-dependent manner without any cytotoxicity. This derivative suppressed PDGF-induced [3H]-thymidine incorporation, cell cycle progression from G0/G1 to S phase, and the phosphorylation of phosphor-retinoblastoma protein (pRb) as well as the expression of cyclin E/D, cyclin-dependent kinase (CDK) 2/4, and proliferating cell nuclear antigen (PCNA). Importantly, 2-nonylamino-DMNQ inhibited the phosphorylation of PDGF receptorbeta(PDGF-Rbeta) enhanced by PDGF at Tyr579, Tyr716, Tyr751, and Tyr1021 residues. Subsequently, 2-nonylamino-DMNQ inhibited PDGF-induced phosphorylation of STAT3, ERK1/2, Akt, and PLCgamma1. Therefore, our results indicate that 2-nonylamino-DMNQ inhibits PDGF-induced VSMC proliferation by blocking PDGF-Rbeta autophosphorylation, and subsequently PDGF-Rbeta-mediated downstream signaling pathways.

Effect of Decursin on the Expression of beta-Catenin and Matrix Metalloproteinase-7 in Prostate Cancer Cell Lines / 대한비뇨기과학회지

PURPOSE: Alterations in the Wnt/beta-catenin pathway are associated with the development and progression of human prostate cancer. Decursin can attenuate the Wnt/beta-catenin pathway. We investigated the relationship between the Wnt/beta-catenin pathway and decursin in prostate cancer cells. MATERIALS AND METHODS: PC-3 and LNCaP cell lines were used. Cell viability was measured with methyl-thiazole tetrazolium bromide (MTT) assays, and cell apoptosis analysis was performed by FACScan. The amount of beta-catenin protein after treatment with decursin was measured by Western blot analysis. Expression of MMP-7 mRNA was detected by real-time polymerase chain reaction (RT-PCR). RESULTS: Death and apoptosis were increased after treatment with decursin 0.5-100 micrometer in PC-3 and LNCaP cells. This was revealed dose and time-dependent increase of cancer cell death on 24, 48 and 72 hours. FACScan showed an increment of apoptosis on 24, 48 hours. Expression of intracellular beta-catenin protein was decreased dose-dependently in both of prostate cancer cell lines. Decursin reduced MMP-7 mRNA expression on 6, 12, 24, 48 hours dose-dependently. CONCLUSIONS: Decursin affects the viability of prostate cancer cells. Increased cancer cell death was associated with increased apoptosis. This study suggests that decursin may play a role in the treatment of prostate cancer.