Uromedic^(■) Pumpkin Seed Derived Δ7-Sterols, Extract and Oil Inhibit 5α-Reductases and Bind to Androgen Receptor in Vitro  

作　　者：Stefan Heim Stephanie Seibt Heike Stier Margret I More 

机构地区：[1]Omega Pharma Manufacturing GmbH&Co.KG,Benzstr.25,Herrenberg,Germany [2]analyze & realize GmbH,Department of Consulting and Strategic Innovation,Waldseeweg 6,Berlin,Germany

出　　处：《Pharmacology & Pharmacy》2018年第6期193-207,共15页药理与制药（英文）

基　　金：Omega Pharma Manufacturing GmbH & Co. KG

摘　　要：Dihydrotestosterone (DHT) is implicated in the development of benign prostate hyperplasia (BPH). We investigated if Uromedic? pumpkin (variety of Cucurbita pepo L. convar. citrullinina GREB. var. styriaca GREB) seed soft extract (active ingredients of GRANUFINK? Prosta forte 500 mg), seed oil and isolated Δ7-sterols could inhibit the conversion of [1,2,6,7-3H(N)]-testosterone to DHT by 5α-reductases. Also, we tested competition with [3H]-DHT for binding to the androgen receptor (AR). Pumpkin seed oil and pumpkin seed soft extract were identified as moderately active inhibitors of 5α-R1 and 5α-R2, with almost similar inhibitory capacities (IC50 5 mg/ml for 5α-R1 and about IC50 = 6 mg/ml for 5α-R2). The isolated Δ7-sterols were more active inhibitors (IC50 = 0.3 mg/ml for 5α-R1, IC50 = 1.0 mg/ml for 5α-R2). All three test compounds bound to the AR dose-dependently, with strong binding by Δ7-sterols (IC50 = 0.2 mg/ml) and weaker binding by pumpkin seed oil (IC50 = 0.4 mg/ml) and pumpkin seed soft extract (IC50 = 1.1 mg/ml). We propose that inhibition of 5α-reductases and competitive binding to the AR are mechanisms of action, by which the Uromedic? pumpkin seed derived test compounds, most specifically Δ7-sterols, counteract DHT and thereby exert clinically positive effects on the prostate, as well as bladder-strengthening effects.Dihydrotestosterone (DHT) is implicated in the development of benign prostate hyperplasia (BPH). We investigated if Uromedic? pumpkin (variety of Cucurbita pepo L. convar. citrullinina GREB. var. styriaca GREB) seed soft extract (active ingredients of GRANUFINK? Prosta forte 500 mg), seed oil and isolated Δ7-sterols could inhibit the conversion of [1,2,6,7-3H(N)]-testosterone to DHT by 5α-reductases. Also, we tested competition with [3H]-DHT for binding to the androgen receptor (AR). Pumpkin seed oil and pumpkin seed soft extract were identified as moderately active inhibitors of 5α-R1 and 5α-R2, with almost similar inhibitory capacities (IC50 5 mg/ml for 5α-R1 and about IC50 = 6 mg/ml for 5α-R2). The isolated Δ7-sterols were more active inhibitors (IC50 = 0.3 mg/ml for 5α-R1, IC50 = 1.0 mg/ml for 5α-R2). All three test compounds bound to the AR dose-dependently, with strong binding by Δ7-sterols (IC50 = 0.2 mg/ml) and weaker binding by pumpkin seed oil (IC50 = 0.4 mg/ml) and pumpkin seed soft extract (IC50 = 1.1 mg/ml). We propose that inhibition of 5α-reductases and competitive binding to the AR are mechanisms of action, by which the Uromedic? pumpkin seed derived test compounds, most specifically Δ7-sterols, counteract DHT and thereby exert clinically positive effects on the prostate, as well as bladder-strengthening effects.

关 键 词：5-Alpha-Reductases 5α-R1 and 5α-R2 Androgen Receptor DIHYDROTESTOSTERONE Uromedic? Pumpkin Seed Oil and Soft Extract (Delta-7) Δ7-Sterols 

分 类 号：R73[医药卫生—肿瘤]