5α-reductase Inhibitory Activity Research Articles

Synthesis of Pregnane Derivatives, Their Cytotoxicity on LNCap and PC-3 Cells, and Screening on 5α-Reductase Inhibitory Activity

A series of epoxy- and/or 20-oxime pregnanes were synthesized from commercially available pregnenolone. Compounds 1, 3, 7, 8 and 11-13 were evaluated for cytotoxicity activity towards LNCaP (androgen-dependent) and PC-3 (androgen-independent) prostate cancer cells. Compound 13 showed the highest activity on both LNCaP (IC50 15.17 μM) and PC-3 (IC50 11.83 μM) cell lines. Compound 11 showed weak activity on LNCaP cells (IC 50 71.85 μM) and 8 showed the weak activity on PC-3 cells (IC50 68.95 μM), respectively. The 5α-reductase II (5AR2) inhibitory effects of compounds 1-3, 5 and 7-13 were investigated in a convenient screening model, in which compounds 5, 8, 11 and 12 were observed to be potential inhibitors of 5α-reductase, in particular, the 4-azasteroid 11, that also inhibited cell proliferation of androgen-dependent cells and 8, that in addition inhibited PC-3 cells more potently than LNCaP cells.

Synthesis and biological activity of progesterone derivatives as 5α-reductase inhibitors, and their effect on hamster prostate weight

In this study, we report the synthesis and biological evaluation of four 6- and 17-substituted progesterone derivatives (7–10). These compounds were prepared from the commercially available 17α-acetoxyprogesterone. The biological effect of these steroids was demonstrated in in vivo as well as in vitro experiments. In the in vivo experiments, we measured the activity of 6–10 on the weight of the prostate glands of gonadectomized hamsters treated with testosterone (T). For the studies in vitro, we determined the IC50 value by measuring the concentration of steroidal derivative that inhibited 50% of the activity of 5α-reductase present in the human prostate. The results from this work indicated that compounds 6–9 significantly decreased the weight of the prostate as compared to testosterone-treated animals and this reduction of prostate weight was comparable to that produced by finasteride. Steroid 8 was the most effective of the tested compounds. However, compound 10 did not exhibit this capacity. On the other hand, 6–9 exhibited a high inhibitory activity for the human 5α-reductase enzyme with IC50 values of 10, 70, 22, and 19 nM, respectively. However, 10 was not effective for the inhibition of 5α-reductase activity. In conclusion, the compounds that contained the acetate ester moiety in the molecule (6, 7, 8, and 9) inhibited the activity of 5α-reductase and decreased the weight of the prostate. Nevertheless, the double bond in ring B seems to diminish the inhibitory potency (7 and 9), since 6, which does not possess a double bond at C-6, had the highest inhibitory activity (the lowest IC50 value).

3D-QSAR studies on unsaturated 4-azasteroids as human 5α-reductase inhibitors: A self organizing molecular field analysis approach

Azasteroids have been reported as inhibitors of human 5α-reductase enzyme. These were designed by substitution of one carbon atom of steroidal A ring by heteroatom nitrogen. Due to lack of information on the crystal structure of human 5α-reductase, 3D-QSAR study has been performed on a series of unsaturated 4-azasteroids using Self Organizing Molecular Field Analysis (SOMFA) for rationalizing the molecular properties and human 5α-reductase inhibitory activities. The statistical results having good cross-validated r2cv (0.783), non cross-validated r2 (0.806) and F-test value (87.282), showed satisfied predictive ability. Analysis of SOMFA models through electrostatic and shape grids provide useful information for the design and optimization of new steroidal human 5α-reductase inhibitors.

Self organizing molecular field analysis on a series of human 5α-reductase inhibitors: Unsaturated 3-carboxysteroid

Steroidal 5 α-reductase is a NADPH dependent enzyme that catalyzes the irreversible conversion of 4-en-3-oxo-steroid testosterone to the corresponding 5 α-H-3-oxo-steroid dihydrotestosterone thus involved in Benign Prostatic Hyperplasia (BPH). As the crystal structure of target enzyme is not available; we have carried out ligand based designing using Self Organizing Molecular Field Analysis (SOMFA). SOMFA, a novel 3D-QSAR methodology used in present case to study the correlation between molecular properties and human 5α-reductase inhibitory activities of a series of unsaturated 3-carboxysteroid. The statistical results, good cross-validated r 2 cv (0.693) and non cross-validated r 2 (0.732), showed satisfied predictive ability. All analysis of SOMFA model may provide some useful information in the design of human steroidal 5α-reductase inhibitors with better spectrum of activity.

Novel C-6 substituted and unsubstituted pregnane derivatives as 5α-reductase inhibitors and their effect on hamster flank organs diameter size

The present study is addressed to ascertain the inhibitory effect of several progesterone derivatives having a chlorine substituent at C-6 (12a–12d), 15 with a bromine substituent at C-6 and 14a–14d, without any halogen atom at C-6 all having an ester side chain at C-17 (benzoate ester bearing a Cl, F and a Br atom at C-4 position of the phenyl ring) on the 5α-reductase enzyme activity present in human prostate. In addition, it was also of interest to investigate the pharmacological effect on hamster flank organs diameter size.In order to study the structure–activity relationships of steroids 12a–12d, 14a–14d and 15 we determined the concentration of these steroids that inhibited 50% of the activity of human prostate 5α-reductase enzyme (IC50), as well as the in vivo effect of these compounds in the hamster flank organs diameter size. We also ascertained, the capacity of these steroids to bind to the androgen receptors present in the rat prostate cytosol using labeled mibolerone (MIB) for monitoring the binding to the androgen receptor.The results from this study indicated that compounds 12a–12d (having a chlorine substituent at C-6), 14a–14d (lacking a halogen atom at C-6), 13 and 15 (having a bromine atom at C-6) showed an increased antiandrogenic effect (lower value for the diameter of the flank organs) as compared to the flank organs from testosterone-treated hamsters. On the other hand, the series of compounds containing a chlorine substituent at C-6 compounds (12a–12d) showed a higher antiandrogenic activity as compared to the compounds lacking a halogen atom at C-6 (14a, 14b and 14d). Although compounds 13 and 15 decreased the flank organs diameter size, however, this increase was not statistically significant as compared to that of the commercially available product finasteride. The steroidal derivatives 13, 14a–14d (lacking the chlorine substituent at C-6) and 15 (having a bromine atom at C-6) exhibited a higher 5α-reductase inhibitory activity (lower IC50 values) as compared to the series of compounds 12a–12d having the halogen substituent at C-6.Finasteride reduced the diameter size of the flank organs. The effect of this steroid and compounds 12a–12d, 13, 14a–14d and 15 on hamster flank organs can be explained by the fact that these steroids did not bind to the androgens receptor, which indicates that its mechanism of action is an inhibiting for the 5α-reductase activity. This enzyme is present in the hamster flank organs and was inhibited by the novel steroids in the human prostate homogenates.

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 5α-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.

Steroid 5α-reductase inhibitory activity of condensed tannins from woody plants

In humans, steroid 5α-reductase is involved in the development of benign prostatic hyperplasia (BPH). We tested the steroid 5α-reductase inhibitory activity of the 70% acetone extract of woody plants. The tannin polymer prepared from the 70% acetone extract showed the highest steroid 5α-reductase inhibitory activity. Furthermore, the steroid 5α-reductase inhibitory activity of tannins was not affected by the addition of superoxide dismutase or catalase. It was concluded that the steroid 5α-reductase inhibitory activity of condensed tannin was caused by binding to the steroid 5α-reductase, rather than from the peroxide/superoxide produced by tannins. The tannins, prepared from tree barks, with potential for steroid 5α-reductase inhibitory activity might be advantageous in therapy for steroid 5α-reductase diseases such as BPH or prostate cancer.

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 5α-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.

Inhibition of 5α-Reductase Activity in SZ95 Sebocytes and HaCaT Keratinocytes In Vitro

Inhibition of 5alpha-reductase type 1 has been considered to be a promising target for treatment of androgen-dependent skin disorders, however, currently published clinical results on acne treatment are rather disappointing. In this study, the influence of selective inhibitors of 5alpha-reductase on testosterone metabolism within SZ95 sebocytes and HaCaT keratinocytes IN VITRO was investigated. In both cell types, the isotype 1 inhibitor MK386 completely inhibited the conversion of testosterone to 5alpha-dihydrotestosterone in concentrations higher than 10 (-9) M. Inhibitors of the isotype 2 such as finasteride, dihydrofinasteride, and turosteride, were >100-fold less active, while, as expected, androgen receptor inhibitors did not affect the 5alpha-reductase activity. MK386, but not finasteride, reduced testosterone-stimulated proliferation and slightly reduced the testosterone-induced increase in the amount of SZ95 sebocyte proteins. The androgen receptor inhibitor cyproterone acetate exhibited no effect on testosterone-induced proliferation, but inhibited the 5alpha-dihydrotestosterone-induced sebocyte proliferation. Our experimental findings and the existing clinical results indicate that the inhibition of 5alpha-reductase activity alone may be insufficient to reduce overall sebocyte activity and improve acne lesions.

New progesterone derivatives as inhibitors of 5α-reductase enzyme and prostate cancer cell growth

In this study we report the synthesis and pharmacological evaluation, in vivo as well as in vitro, of four new progesterone derivatives 4–7. The evaluation in vivo was carried out on gonadectomized male hamsters that were injected subcutaneously daily with 1 mg/Kg of testosterone (T) and/or 1 mg/Kg of finasteride, or with 2 mg/Kg of the novel compounds. It was observed that when testosterone (T) and finasteride or compound 4 were injected together, the weight of the prostate decreased significantly as compared to that of testosterone-treated animals. Compounds 5–7 did not show any in vivo activity.The 5α-reductase inhibitory activity of the novel compounds was determined in vitro using human prostate homogenates; the steroids 4–7 inhibited the 5α-reductase activity with IC50 values lower than that for the reference compound finasteride. 3.The effect of compounds 4–7 on the growth of lymphocytes and prostate cancer culture cells line was that steroid 4 inhibited the growth of both cells lines at a concentration of 50 μM and showed a cytotoxic effect whereas compounds 5–7 showed a much lower inhibition. Nevertheless steroids 4–7 didn't exhibit any toxic effects in vivo since the animals remained alive during the six days of treatment.

Phase I study of a methanol extract of Ganoderma lucidum, edible and medicinal mushroom, in men with mild symptoms of bladder outlet obstruction

A methanol extract of G lucidum shows the strongest 5α-reductase inhibitory activity among the extracts of 19 edible and medicinal mushrooms (J Wood Sci. 51:189–192, 2005). A phase I clinical trial was conducted to evaluate the safety and efficacy of the extract of G lucidum in men with mild symptoms of bladder outlet obstruction (BOO).

Anti-androgenic activities of Ganoderma lucidum

The inhibitory effects of methanol extracts of 19 edible and medicinal mushrooms on 5α-reductase activity were examined. The extract of Ganoderma lucidum Fr. Krast (Ganodermataceae) showed the strongest 5α-reductase inhibitory activity. The treatment of the fruit body of Ganoderma lucidum or the extract prepared from it significantly inhibited the testosterone-induced growth of the ventral prostate in castrated rats. These results showed that Ganoderma lucidum might be a useful ingredient for the treatment of benign prostatic hyperplasia (BPH).

The effect of strain, growth stage, and cultivating condition of Ganoderma lucidum on 5α-reductase inhibition

The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5α-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5α-reductase inhibitory activity among the extracts tested.

New 5α-reductase inhibitors: In vitro and in vivo effects

The enzyme 5α-reductase is responsible for the conversion of testosterone (T) to its more potent androgen dihydrotestosterone (DHT). This steroid had been implicated in androgen-dependent diseases such as: benign prostatic hyperplasia, prostate cancer, acne and androgenic alopecia. The inhibition of 5α-reductase enzyme offers a potentially useful treatment for these diseases. In this study, we report the synthesis and pharmacological evaluation of several new 3-substituted pregna-4, 16-diene-6, 20-dione derivatives. These compounds were prepared from the commercially available 16-dehydropregnenolone acetate. The biological activity of the new steroidal derivatives was determined in vivo as well as in vitro experiments. In vivo experiments, the anti-androgenic effect of the steroids was demonstrated by the decrease of the weight of the prostate gland of gonadectomized hamster treated with T plus finasteride or the new steroids. The IC 50 value of these steroids was determined by measuring the conversion of radio labeled T to DHT. The results of this study carried out with 5α-reductase enzyme from hamster and human prostate showed that four of the six steroidal derivatives ( 5, 7, 9, 10) exhibited much higher 5α-reductase inhibitory activity, as indicated by the IC 50 values than the presently used Proscar 3 (finasteride). The comparison of the weight of the hamster's prostate gland indicated that compound 5 had a comparable weight decrease as finasteride. The overall data of this study showed very clearly those compounds 5, 7, 9, 10 are good inhibitors for the 5α-reductase enzyme.

Synthesis and Pharmacological Evaluation of New Progesterone Esters as 5.ALPHA.-Reductase Inhibitors

In this study we report the synthesis and pharmacological evaluation of four new progesterone derivatives; 17alpha-hydroxy-16beta-methylpregna-4,6-diene-3,20-dione 12, 17alpha-cyclopropylcarbonyloxy-16beta-methylpregna-4,6-diene-3,20-dione 13, 17alpha-cyclobutylcarbonyloxy-16beta-methylpregna-4,6-diene-3,20-dione 14, 17alpha-acetoxy-16beta-methylpregna-4,6-diene-3,20-dione 15 and the pregnatriene compound 17alpha-cyclobutylcarbonyloxy-16beta-methylpregna-1,4,6-triene-3,20-dione 16. The pharmacological effect of these compounds was determined in vivo as well as in vitro. The evaluation in vivo was carried out on gonadectomized male hamsters that were injected subcutaneously daily with testosterone (T) and/or finasteride, or with the novel compounds. At the end of the treatments the animals were sacrificed and the prostates were weighed. It was observed that when testosterone (T) and finasteride or compounds 12-16 were injected together, the weight of the prostate decreased significantly as compared to that of the testosterone-treated animals. The 5alpha-reductase inhibitory activity was evaluated in vitro using human prostate homogenates. These experiments showed the following IC50 values: compound 12 (alcohol at C-17) 1.2 x 10(-6) M, 13 (cyclopropyl substituent at C-17) 7.9 x 10(-10) M, 14 (cyclobutyl substituent) 3.2 x 10(-8) M, 15 (acetoxy substituent) 6.3 x 10(-11) M and 16 (cyclobutyl substituent) 3.9 x 10(-6) M. It is evident from these data that when the size of the substituent at C-17 is decreased, the 5alpha-reductase inhibitory activity increases. Apparently, in this biological model, the 5alpha-reductase inhibitory activity depends upon the steric effect of the substituent at C-17. However, the free alcohol 12 showed much lower 5alpha-reductase inhibitory activity.

5α-Reductase inhibition activity of steroids isolated from marine soft corals

The aim of this study is to determine the 5α-reductase inhibitory activity of several new steroidal compounds PR-01– PR-07 by measuring the conversion of [ 3 H ]T to[ 3 H ]DHT in Penicillium crustosum broths. These compounds were obtained from marine soft corals collected on the coasts of Andaman and Nicobar at Hori, Natkal and Kalipur (Diglipur) Islands and identified as Sinularia grandilobata Verseveldt, Sinularia crassa Tixier- Durivault, Sinularia gravis Tixier- Durivault, Sinularia sp., Lobophytum sp., Lobophytum crassum and Cladiella sp. PR-01– PR-04 significantly inhibited the conversion of [ 3 H ]T to [ 3 H ]DHT ( P<0.05) whereas PR-05 and PR-06 did not show an appreciable difference ( P>0.05) in this model. On the other hand PR-07 stimulated ( P<0.05) the enzymatic reaction.

5α‐Reductase Inhibitory and Antiandrogenic Activities of Novel Steroids in Hamster Seminal Vesicles.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Effects of single non- ortho, mono- ortho, and di- ortho chlorinated biphenyls on cell functions and proliferation of the human prostatic carcinoma cell line, LNCaP

This study investigated the effects of the non- ortho 3,3′,4,4′,5-pentachlorobiphenyl (PCB 126) and 3,3′,4,4′-tetrachlorobiphenyl (PCB 77), the mono- ortho 2,3′,4,4′,5-pentachlorobiphenyl (PCB 118), and the di- ortho substituted 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB 153) on the human prostatic carcinoma cell line LNCaP. Activities of 5α-reductase and ethoxyresorufin- O-deethylase (EROD) secretion of testosterone-regulated prostatic specific antigen (PSA) and cell proliferation served as specific and general cell markers. The two non- ortho (dioxin-like) PCBs, PCB 126 and PCB 77, showed anti-androgenic properties. Both PCBs reduced androgen-depending PSA secretion and cell proliferation, and inhibited the DHT-producing enzyme 5α-reductase in a concentration-dependent manner. In contrast, the ortho-substituted PCBs, PCB 118 and PCB 153, had no effect on 5α-reductase. However, they had a biphasic effect on LNCaP cell proliferation. PCB 153 and, to some extent, PCB 118 induced cell proliferation and PSA secretion at low concentrations, whereas, these parameters were reduced at high concentrations. Since EROD induction and inhibition of 5α-reductase activity was not observed, these findings suggest an AhR and AR independent mechanism and post-transcriptional target sites should be considered. The effects of PCB 126 on cell proliferation, PSA secretion, and 5α-reductase activity may be partly a result of AhR-dependent inhibition. In conclusion, the endocrine activity of PCBs via direct steroid hormone receptor-mediated and Ah receptor-mediated pathways are well known. However, the modulation of post-transcriptional targets may account for some of the endocrine disrupting properties of single PCB congeners.

De Sign and Synthesis of 1,2,4‐Oxadiazole Derivatives as Non‐Steroidal 5α‐Reductase Inhibitors

AbstractThe purpose of this study was to synthesize compounds in which the 1,2,4‐oxadiazole moiety replaced the amide bond of ONO3805 and to evaluate its 5α‐reductase inhibitory activity as a potential benign prostatic hyperplasia therapeutic target. Four 1,2,4‐oxadiazole derivatives, 1,2,8, and 20, were evaluated in vitro against 5α‐reductase of rat liver microsome. The prepared 1 and 2 possessed similar binding affinity (Ki) to that of ONO3805. Therefore, the use of 1,2,4‐oxadiazole ring as surrogate of the amide bond in ONO3805 has a successful result in this study. It leads not only to enhance chemical stability but also to maintain meaningful inhibitory activity. The butyric acid moiety of these inhibitors is considered to play an important role in mimicing the phosphoric acid portion of coenzyme‐NADPH in interacting with the active site of 5α‐reductase.

5α-Reductase inhibitory compounds produced by polymerization of resveratrol with horseradish peroxidase

To produce 5α-reductase inhibitory compounds, resveratrol was enzymatically oxidized in a horseradish peroxidase (HRP)/H2O2 system. Ethyl acetate extract of the oxidation products showed strong 5α-reductase inhibitory activity with 10%–15% organic solvents in the system, whereas without organic solvent little inhibitory activity was exhibited. The optimum pH of enzymatic oxidation for acquisition of the inhibitory activity was 4.5. The inhibitory compounds were isolated and identified as resveratroltrans-dehydrodimer and resveratrolcis-dehydrodimer by comparing with published nuclear magnetic resonance data. The two resveratrol dehydrodimers have stronger inhibitory activity than natural resveratrol dimers and trimers found inShorea species.