Inhibition of steroid 5α-reductase by “inverted”, competitive inhibitors

Advances in the design and discovery of drugs for the treatment of prostatic hyperplasia

INTRODUCTION

Benign prostatic hyperplasia (BPH) is a common medical problem in nearly 80% of geriatric male population severely affecting the quality of life. Several strategies has been suggested in the past for the management of BPH, but only α-blockers and 5α-reductase inhibitors are in clinical use. This review aims to give deep insight into advances in the design and discovery of newer chemical entities as 'druggable' molecule for the management of BPH.

AREAS COVERED

In this review, the authors cover various classes of drugs that have shown their potential for management of BPH. These drugs include α-adrenergic antagonists, 5α-reductase inhibitors, phytochemical agents, phosphodiesterase inhibitor, luteinizing hormone releasing hormone antagonists and muscarinic receptor antagonists. Literature searches were carried out using Google Scholar, SciFinder and PubMed.

EXPERT OPINION

The exact etiology of BPH is unknown; however, several mechanisms may be involved in the progression of the disease. Beside surgery and watchful waiting, medical therapies to treat BPH include α-adrenergic antagonist and 5α-reductase inhibitors. Phytotherapeutic agents are also used in some countries. Various other chemical classes of drugs are proposed for the treatment of the disease, but none of them have reached the clinic. Many classes of drugs are currently undergoing clinical trials such as phosphodiesterase inhibitors, luteinizing hormone releasing hormone antagonists and muscarinic receptor antagonists. The current need is to develop a potent, efficacious and highly selective drug for the treatment of BPH.

Ganoderic acid DM: anti-androgenic osteoclastogenesis inhibitor

Prostate cancer is the most common cancer in men in Western countries, with a high incidence of bone metastasis. Ganoderic acid DM, with 5alpha-reductase inhibitory and androgen receptor (AR) binding activity, isolated from the ethanol extracts of Ganoderma lucidum, can inhibit prostate cancer cell growth and block osteoclastogenesis.

The anti-androgen effect of ganoderol B isolated from the fruiting body of Ganoderma lucidum

The anti-androgenic activity of the ethanol extract of the fruiting body of Ganoderma lucidum has been previously reported. Ganoderol B with 5alpha-reductase inhibitory activity and the ability to bind to androgen receptor (AR) can inhibit androgen-induced LNCaP cell growth and suppress regrowth of the ventral prostate induced by testosterone in rats. The down-regulation of AR signaling by ganoderol B provides an important mechanism for its anti-androgenic activity. In view of the fact that PSA (prostatic specific antigen, a well-accepted prognostic indicator of prostate cancer) is down-regulated, an important implication of this study is that ganoderol B intervention strategy aimed at toning down the amplitude of androgen signaling could be helpful in controlling morbidity of prostate cancer. In conclusion, our result suggests that ganoderol B might be useful in prostate cancer and benign prostatic hyperplasia (BPH) therapy through suppressing the function of androgen and its receptor.

Azasteroids as antifungals

Azasteroids and derivatives thereof with antifungal potential are reviewed. Special emphasis is put on steroids with nitrogen as part of the steroidal framework, natural substances, and lines of development emerging from them.

Structure activity relationship study of known inhibitors of the enzyme 5 alpha-reductase (5AR)

Preliminary results of a modelling study of both steroidal and non-steroidal inhibitors of 5 alpha-reductase (5AR) are described in order to elucidate the essential structural requirements needed for the design of novel non-steroidal inhibitors. The study suggests that: (i) there is a requirement for groups to mimic the C(3) = O of the steroid substrate A-ring; (ii) the area of the active site about the C(17)-OH position of the substrate does not appear to possess hydrogen bonding groups and is unrestricted.

Synthesis of 4,17-diazasteroid inhibitors of human 5 alpha-reductase

The synthesis of the 17-aza isomer of finasteride is described. With the side chain amide group of the compound existing in the Z configuration the structure is similar to one of the two favored conformations of finasteride. A series of 4,17-diazasteroids was assayed against the isoenzymes of human 5 alpha-reductase.

Structure of 3 beta-hydroxy-16-oxo-24-nor-17-azachol-5-eno-23-nitrile and its 20S epimer

The structures of the title compounds have been investigated in solid state by X-ray and in solution by NMR methods. The configurations at C20 and the preferred conformations of both epimers were established. A full assignment of signals in 1H and 13C NMR spectra was done.