Clinical and genetic features of 5 alpha-reductase type2 deficiency caused by SRD5A2 gene variants / 中华内分泌代谢杂志

Objective:To explore the clinical and genetic characteristics of 5α-reductase 2 deficiency syndrome(5α-RD2).Methods:Retrospective analysis of three cases of 5α-RD2 to summarize clinical data. Genetic testing was conducted using chromosome karyotyping analysis, whole-exome sequencing(WES), Sanger sequencing, and bioinformatics analysis. The effect of the novel variant on the structure of the 5α-reductase was evaluated by studying the homology modeling structure using SWISSMODEL and PyMoL.Results:The patients of all three cases have social gender as female. In Case 1, a 6-year-old patient sought medical attention due to abnormal external genitalia development. In Cases 2 and 3, 15-year-old patients presented with primary amenorrhea, and they showed masculinization of secondary sexual characteristics during puberty. In all three cases, the external genitalia exhibited varying degrees of masculinization, with clitoromegaly resembling a small penis and accompanying cryptorchidism. In Case 2, an hCG stimulation test was performed, and the testosterone/dihydrotestosterone(DHT) ratio was found to be 17.4. The karyotype of all three patients was 46, XY. Whole-exome sequencing(WES) detected SRD5A2 gene variants in all cases, with genotypes being p. Gln6Ter/p.Arg227Gln, p. Gln6Ter/p.Pro250Ala, and p. Arg227Ter/p.His89Tyr, respectively. Parental validation confirmed compound heterozygous mutations in all cases. The novel variant p. Pro250Ala was identified and classified as a likely pathogenic variant according to ACMG guidelines. Protein modeling analysis indicated that this variant may affect the binding of 5α-reductase 2 to NADPH. In Case 1, male gender was chosen, and a laparoscopic bilateral orchiopexy was performed. In Case 2, female gender was chosen, and testectomy and vaginoplasty were performed. The gender selection for Case 3 has not been definitively determined yet.Conclusions:Abnormal external genitalia is a common phenotype of 5α-RD2. After hCG stimulation test, there is a significant increase in the testosterone/dihydrotestosterone(DHT) ratio, which indicates that Sanger sequencing of the SRD5A2 gene can be directly performed. 5α-RD2 exhibits significant clinical heterogeneity, and WES can facilitate the differential diagnosis of 46, XY disorders of sex development. The study also reported a novel variant, p. Pro250Ala, which enriches the SRD5A2 gene variant database.

The extract of Celtis choseniana Nakai alleviates testosterone-induced benign prostatic hyperplasia through inhibiting 5α reductase type 2 and the Akt/NF-κB/AR pathway / 中国天然药物

Benign prostatic hyperplasia (BPH) is a chronic male disease characterized by the enlarged prostate. Celtis chosenianaNakai (C. choseniana) is medicinally used to alleviate pain, gastric disease, and lung abscess. In this study, the effect of C. choseniana extract on BPH was investigated using testosterone-induced rats. Sprague Dawley rats were divided into five groups: control, BPH (testosterone 5 mg·kg-1), Fina (finasteride 2 mg·kg-1), and C. choseniana (50 and 100 mg·kg-1). After four weeks of TP treatment with finasteride or C. choseniana, prostate weights and DHT levels were measured. In addition, the prostates were histopathologically examined and measured for protein kinase B (Akt)/nuclear factor-κB (NF-κB)/AR signaling, proliferation, apoptosis, and autophagy. Prostate weight and epithelial thickness were reduced in the C. choseniana groups compared with that in the BPH group. The extract of C. choseniana acted as a 5α reductase inhibitor, reducing DHT levels in the prostate. Furthermore, the extract of C. choseniana blocked the activation of p-Akt, nuclear NF-κB activation and reduced the expression of AR and PSA compared with BPH. Moreover, the expression of Bax, PARP-1, and p53 increased, while the expression of bcl-2 decreased. The present study demonstrated that C. choseniana extract alleviated testosterone-induced BPH by suppressing 5α reductase and Akt/NF-κB activation, reducing AR signaling and inducing apoptosis and autophagy in the prostate. These results suggested that C. choseniana probably contain potential herbal agents to alleviate BPH.

Active constituents of Urtica fissa in inhibition of benign prostatic hyperplasia / 中国中药杂志

The present study investigated the material basis of Urtica fissa for the inhibition of benign prostatic hyperplasia(BPH). The active fractions were screened, and the extracts of dichloromethane and ethyl acetate exhibited significantly inhibitory activities against 5α-reductase in vitro and BPH in model rats. The chemical constituents in the active fractions were systematically investigated, and 28 compounds were obtained, which were identified as lobechine methyl ester(1), dibutyl-O-phthalate(2), 1-monolinolein(3), epipinoresinol(4), 5-hydroxy-3,4-dimethyl-5-pentanyl-2(5H)-furanone(5), E-7,9-diene-11-methenyl palmitic acid(6), evofolin B(7), ficusal(8), threo-2,3-bis-(4-hydroxy-3-methoxyphenyl)-3-ethoxypropan-1-ol(9), α-viniferin(10),(9R,7E)-9-hydroxy-5,7-mengatigmadien-4-one-9-O-β-D-glucopyranoside(11), indole-3-carboxaldehyde(12), p-hydroxy ethyl cinnamate(13), benzyl alcohol-O-β-D-glucoside(14), L-methionine(15), 4-methoxyaniline(16), 6-aminopurine(17), 8'-acetyl oilvil(18), 4-methoxyl-8'-acetyl oilvil(19), vanillic acid(20), β-hydroxypropiovanillone(21), 7-hydroxy-6-methoxycoumarin(22), p-hydroxybenzaldehyde(23), pinoresinol(24), erythro-1,2-bis-(4-hydroxy-3-methoxyphenyl)-1,3-propanediol(25), urticol(26), urticol-7-O-β-D-glucopyranoside(27), and lobechine(28). Compounds 1-17 were isolated from U. fissa for the first time. Meanwhile, compound 1 was a new natural product. Compounds 10, 11, 19, 21, and 27 exhibited significant inhibitory effects on 5α-reductase.

Lignans with inhibitory effect on 5α-reductase from Urtica cannabina / 中国中药杂志

The lignans in Urtica cannabina were isolated by preparative HPLC, silica, and ODS column chromatographies, and identified by NMR and HR-MS. The inhibitory activities on 5α-reductase were evaluated in vitro. As a result, ten secolignans,(2R,4S)-2,4-bis(3-methoxyl-4-hydroxyphenyl)-3-butoxypropanol(1), 3,4-trans-3-hydroxymethyl-4-[bis(3,4-dimethoxyphenyl)methyl] butyrolactone(2), 3,4-trans-3-hydroxymethyl-4-[(3,4-dimethoxyphenyl)(3-methoxyl-4-hydroxyphenyl)methyl] butyrolactone(3), 3,4-trans-3-hydroxymethyl-4-[bis(3-methoxyl-4-hydroxyphenyl)methyl] butyrolactone(trans urticol, 4), 3,4-trans-3-hydroxymethyl-4-[bis(3,4-dimethoxyphenyl)methyl] butyrolactone-3-O-β-D-glucopyranoside(5), 3,4-trans-3-hydroxymethyl-4-[(3,4-dimethoxyphenyl)(3-methoxyl-4-hydroxyphenyl)methyl]butyrolactone-3-O-β-D-glucopyranoside(6), 3,4-trans-3-hydroxymethyl-4-[bis(3-methoxyl-4-hydroxyphenyl)methyl]butyrolactone-3-O-β-D-glucopyranoside(trans-urticol-7-O-β-D-glucopyranoside, 7), cycloolivil-4-O-β-D-glucopyranoside(8), isolariciresinol-4'-O-β-D-glucopyranoside(9), and olivil-4'-O-β-D-glucopyranoside(10), together with a polyphenol [α-viniferin(11)], were isolated from U. cannabina for the first time. Compound 1 was a new lignan. Compound 7 was potent in inhibiting 5α-reductase.

Screening of type II 5α-reductase inhibitors from traditional Chinese medicine based on molecular docking and molecular dynamics simulation technology / 中草药

Objective: To screen the potential type II 5α-reductase inhibitors from active ingredients of traditional Chinese medicine (TCM) based on molecular docking and molecular dynamics (MD) simulation technology. Methods: The molecular docking was used to screen 26 monomer compositions from TCM. Based on the docking results, MD was performed to evaluate the binding strength of compounds with protein. The binding free energy of the system was calculated using the MM/PBSA method. The in vitro micro-reaction system was used to investigate biological activity. Results: The binding energies of 26 monomer compositions from TCM to type II 5-alpha Reductase were different. Among them, ligustroflavone, safflower yellow and hinokiflavone have low binding energies to type II 5-alpha reductase, and their binding abilities were strong. The molecular dynamics simulation results are consistent with the docking results (binding capacity: ligustroflavone-protein > safflower yellow-protein > hinokiflavone-protein). The three components ligustroflavone, safflower yellow and hinokiflavone have a certain inhibitory activity on type II 5α-reductase with the IC50 value of (42.12 ± 3.83), (69.06 ± 6.35), and (191.28 ± 5.90) μmol/L, respectively. Conclusion: Among the screened 26 monomer compositions, ligustroflavone, safflower yellow and hinokiflavone have the potential to be used in the study of treatment and prevention of androgen-dependent diseases, which provides a reference for further exploration and discovery of type II 5α-reductase inhibitors.

Melandrium firmum Extract Promotes Hair Growth by Modulating 5α-Reductase Activity and Gene Expression in C57BL/6J Mice

BACKGROUND: In our preliminary study, we screened for their potential to inhibit 5α-reductase, and Melandrium firmum (MF) extract showed the most potent activity as confirmed by high-performance liquid chromatography (HPLC). OBJECTIVE: This study aimed to investigate the effects of MF extract on 5α-reductase activity and its mechanisms of action in the prevention or treatment of androgenetic alopecia. METHODS: HPLC was used to measure 5α-reductase activity. The hair growth-promoting effect of MF extract in the shaved dorsal skin of C57BL/6J mice was studied for 30 days. Hair follicles were examined by histological examination. Protein and mRNA levels of growth factors involved in hair growth were determined by western blotting, and reverse transcription-polymerase chain reaction (RT-PCR) and qPCR, respectively. Cell proliferation was measured by (3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. RESULTS: MF extract at 0.5 mg/ml showed 43.5% inhibition of 5α-reductase. MF extract promoted hair growth by inducing anagen phase reflected by skin color, hair density, and the number and size of hair follicles. It not only reduces the expression of transforming growth factor-beta 1 (TGF-β1) and Dickkopf-1 (DKK-1), but also markedly upregulated insulin-like growth factor 1 and keratinocyte growth factor in the dorsal dermal tissue. Ursolic acid, ecdcysteron, and ergosterol peroxide were identified as active constituents by activity-guided fractionation to inhibit 5α-reductase. They decreased the gene expression of TGF-β1 and DKK-1 in human hair dermal papilla cells. CONCLUSION: In summary, these finding indicate that MF extract might be a good drug candidate for hair growth promotion.

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.

Identification of three novel SRD5A2 mutations in Chinese patients with 5α-reductase 2 deficiency / 亚洲男科学杂志(英文版)

In this study, we investigated the genetics, clinical features, and therapeutic approach of 14 patients with 5α-reductase deficiency in China. Genotyping analysis was performed by direct sequencing of PCR products of the steroid 5α-reductase type 2 gene (SRD5A2). The 5α-reductase activities of three novel mutations were investigated by mutagenesis and an in vitro transfection assay. Most patients presented with a microphallus, variable degrees of hypospadias, and cryptorchidism. Eight of 14 patients (57.1%) were initially reared as females and changed their social gender from female to male after puberty. Nine mutations were identified in the 14 patients. p.G203S, p.Q6X, and p.R227Q were the most prevalent mutations. Three mutations (p.K35N, p.H162P, and p.Y136X) have not been reported previously. The nonsense mutation p.Y136X abolished enzymatic activity, whereas p.K35N and p.H162P retained partial enzymatic activity. Topical administration of dihydrotestosterone during infancy or early childhood combined with hypospadia repair surgery had good therapeutic results. In conclusion, we expand the mutation profile of SRD5A2 in the Chinese population. A rational clinical approach to this disorder requires early and accurate diagnosis, especially genetic diagnosis.

The phenotype and genotype characteristics of 41 patients with steroid 5α-reductase type 2 deficiency / 中华内分泌代谢杂志

Objective To investigate the cliuical phenotype and the genotype of forty-one patients with steroid 5α-reductase type 2 deficiency.Methods The clinical data were collected including physical examination,medical history,laboratory test,as well as ultrasonic examination.Genomic DNA was extracted from peripheral blood leukocytes.Sanger sequencing and targeted gene captured next-generation sequencing were applied to detect the SRDSA2 gene mutation.Results All the patients are Han nationality and their ages ranged from 4 months to 11 years old.The karyotypes of 41 patients were 46,XY and all SRY genes were detected as positive.There were 26 (63％) patients manifested isolated micropenis,and the rest of fifteen patients were hypospadias associated with microphallus accounting for 37％.There were 39 patients who carried biallelic mutation.Two cases just identified one allele mutation.Sixteen gene mutation types were confirmed.Among them c.725A ＞ G (p.Tyr242Cys),c.694C ＞ G (p.His232Asp),and c.548-9T＞G are the novel gene types.The allele frequency of c.680G＞A (p.Arg227Gln) is 60％ (48/80).Conclusion The primary manifestations of patients with steroid 5α-reductase type 2 deficiency were micropenis or hypospadias accompanied with micropenis.c.680G＞A (p.Arg227Gln) is the predominantly mutation type of Chinese patient with steroid 5α-reductase type 2 deficiency.

Research progress of 5α-reductase 2 deficiency / 国际儿科学杂志

Steroid 5α-reductase type 2 deficiency is caused by mutations in the SRD5A2 gene and is a congenital metabolic defect of autosomal recessive inheritance. The variety of gene mutations causes different levels of enzyme deficiency and results in different clinical phenotype,from the typical male sexual characteris-tics to the complete female sexual characteristics( small penis,perineal scrotal hypospadias and complete female phenotype). In puberty,the child with 5α-reductase 2 deficiency may undergo virilization. The correlation be-tween clinical phenotype and genotype is still under investigation. Steroid 5α-reductase type 2 deficiency and oth-er 46,XY disorders of sex development including androgen insensitivity syndrome have similar clinical charac-teristics,and 5α-reductase type 2 deficiency should be differentiated from other 46,XY disorders of sex develop-ment. The diagnosis of 5α-reductase type 2 deficiency is based on clinical manifestations,imaging examination, hormone detection,urinary steroid analysis and genetic testing,etc. The cutoff value of hormonal diagnosis still needs to be studied and the diagnosis should be further standardized. In most patients,the shift from female to male will occur around puberty,and may cause gender anxiety. The patient may have gender social identity crisis and other ethical controversies. In terms of treatment,gender assignment and gender role management are contro-versial,and surgical procedures need to be further studied. This paper reviews the clinical features,clinical pheno-type and genotype,the differential diagnosis,diagnosis basis and treatment strategy as well as the future challen-ges of 5α-reductase type 2 deficiency,in order to alleviate the sufferings caused by later gender transition in pu-berty and improve the quality of life.

New progress in diagnosis and treatment of 5α-reductase type 2 deficiency / 国际儿科学杂志

5α-reductase type 2 deficiency (5α-RD2)is a monogenic genetic disease with autosomal recessive inheritance.It is a common type of 46,XY disorders of sex development and is caused by deficiency of 5α-reductase type 2.Due to the complex and diverse clinical presentations and nigher overlaps with other types of 46,XY DSD,it is difficult to diagnose.Early diagnosis and treatment may improve the prognosis.In this paper,we review the literature and summarize the progress of the diagnosis and treatment of 5α-reductase type 2 deficiency,aiming to facilitate clinical diagnosis and treatment of the disease.

The key problems in benign prostatic hyperplasia and lower urinary tract symptoms medical treatment / 中华泌尿外科杂志

The relationship between benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS) in elderly men is very close.Although medical therapy plays an important role in the treatment of BPH/LUTS,there are still some unclear and urgent problems in the pharmaceutical treatment,including how to improve patients' symptoms and delay the clinical progression.There are a plenty of medicines for BPH/LUTS treatment,but how to make a reasonable choice,what is the evidence for the combination of those medicines and whether they may cause side effects? This review will focus on these key and controversial problems by literature review.

Prostate-Specific Antigen Kinetics Following 5α-Reductase Inhibitor Treatment May Be a Useful Indicator for Repeat Prostate Biopsy

PURPOSE: To evaluate parameters for determining repeat prostate biopsy in patients with 5α-reductase inhibitor (5ARI) treatment after initial negative biopsy. MATERIALS AND METHODS: From January 2007 to December 2015, patients who underwent a repeat prostate biopsy after an initial negative biopsy were enrolled from multiple institutions. Serial prostate-specific antigen (PSA) levels after the initial biopsy were analyzed for PSA kinetics. Clinicopathologic variables were evaluated according to the use of 5ARIs after the initial negative biopsy. RESULTS: Of 419 patients with initial negative biopsies (median age=67.0 years, median PSA=6.31 ng/mL), 101 patients (24.1%) were diagnosed with prostate cancer at the repeat biopsy. An increase in PSA level at 18 months, compared to that at 6 months, was a predictor of a positive repeat biopsy. However, the use of 5ARIs was not identified as a predictor. Of 126 patients receiving 5ARI treatment after the initial biopsy, 30 (23.8%) were diagnosed with prostate cancer at the repeat biopsy. Increase in PSA level at more than two time points after 6 months of 5ARI treatment (odds ratio=4.84, p=0.005) was associated with cancer detection at the repeat biopsy. There were no significant 5ARI group-related differences in the detection rates of prostate and high-grade cancers (Gleason score ≥7). CONCLUSION: The effects of 5ARIs on prostate cancer detection and chemoprevention remain uncertain. However, more than two increases in PSA level after 6 months of 5ARI treatment may indicate the presence of prostate cancer.

The analysis of gene mutation and diagnosis and treatment of 5α-reductase 2 deficiency in a child / 临床儿科杂志

Objective To explore the clinical feature and gene mutation in steroid 5α-reductase 2 deficiency (SRD5A2). Method The clinical data of SRD5A2 in a child with vulva abnormality as the first manifestation was retrospectively analyzed. Results This was a 29-month-old child, whose social gender was female. The level of her basic luteinizing hormone (LH) was 0.07 mIU/mL, and follicle-stimulating hormone was (FSH) 0.39 mIU/mL. The baseline levels of testosterone (T), dihydrotestosterone (DHT), 17-hydroxyprogesterone (17-OHP) and androstendione (A2) were 0.06 ng/mL, 19.67 pg/mL, 1.20 ng/mL, and 0.07 ng/mL respectively. Those levels were 3.65 ng/mL, 68.25 pg/mL, 51.72 ng/mL, and 14.70 ng/mL respectively after Human chorionic gonadotropin (HCG) stimulation. The levels of her anti-mullerian hormone (AMH) was 22.97 ng/mL, and inhibin B (INH-B) was 274.4 pg/mL. The uterus and ovaries were not detected by Pelvic ultrasound and MRI. The chromosome showed 46, XY. Sex determination (SRY) gene detection showed normal. Androgen receptor (AR) gene detection showed negative. There was pathogenic mutation of 5α-reductase 2 (SRD5A2) gene in peripheral blood of the child and her parents. The penis grows 2 cm after 4 months of treatment with 2.5% DHT gel. Conclusion SRD5A2 is diagnosed mainly based on the increase of T/DHT after HCG stimulation experiment and it can be confirmed by detection of pathogenic SRD5A2 mutation.

Effect of dutasteride to benign prostatic hyperplasia with large volume in the medium-short term / 中华泌尿外科杂志

Objective To verify the short and medium term effect of dutasteride in the treatment of lower urinary tract symptoms ( LUTS) secondary to benign prostatic hyperplasia( BPH) with prostate volume≥40 ml.Methods One hundred and seven patients diagnosed as BPH accompanying moderate-to-severe LUTS who met the inclusion/exclusion criteria were enrolled from July 2013 to September 2014.After 12 weeks of treatment with dutasteride 0.5 mg/d, the primary outcome was international prostate symptom score (IPSS) change from baseline at Week 12, and the secondary outcome was Quality of Life (QOL) score before and after the treatment, maximun flow rate ( Qmax ) , and the change in residual urine volume. Comparing with baseline, patients with the rate of IPSS decline ≥30% ( effective group) continued taking dutasteride for another 4 weeks then undergoing the prostate volume and PSA measurement.In addition, patients with the rate of IPSS decline <30% were administered combination therapy with dutasteride and tamsulosin (0.2mg/d), their IPSS at Week 16 were compared with that at Week 12, and their prostate volume and PSA level were followed up until Week 20.The prostate volume and PSA changing were followed up.Results Compared with baseline, after 12 weeks of treatment with dutasteride, patients'IPSS decreased 5.54 points ( P <0.01 ) , including 59 patients ( 55.14%) with IPSS decline rate ≥30%, QOL score decreased 1.56 points (P<0.01), Qmax increased 1.07 ml /s (P=0.049), and residual urine decreased 6.46 ml (P=0.107).IPSS declined ≥30% in 42 patients at Week 12, whose prostate volume reduced 14.15%at Week 16 follow-up, with PSA declining of 0.68 ng /ml in 32 tested cases ( P=0.008).IPSS declining <30%in 36 patients at Week 12 was followed up to Week 20, and their prostate volume reduced 11.89%, with PSA declining of 0.18 ng/ml ( P=0.589) in 33 tested patients.Conclusions Dutasteride can improve the lower urinary tract symptom in patients who are diagnosed as BPH accompanying moderate-to-severe LUTS with prostate volume ≥ 40 ml significantly.Tamsulosin add-on treatment benefited most patients.

The correlation between phenotype and genotype of 5α-reductase 2 deficiency in 5 children / 临床儿科杂志

Objective To explore the correlation between phenotype and genotype of 5α-reductase 2 deficiency. Methods The clinical data of five children with 5α-reductase 2 deficiency were retrospectively analyzed and the relation between their clinical phenotype and genotype were analyzed. Results All of these five children presented small penis and testicular hypoplasia, three of whom had ones similar to the clitoris appearance. The testosterone/dihydrotestosterone (T/DHT) ratio was 10.26-64.99 after human chorionic gonadotropin (hCG) stimulation. Gene detection showed one case had c.680G>A homozygous mutation and the others were compound heterozygous mutations. The mutations were mainly missense mutations, followed by deletion, duplication and nonsense mutations. Conclusion The 5α-reductase 2 deficiency has different degrees of abnormal genital development. Genetic testing contributed to the diagnosis of this disease.

Inhibitory Effect of Neferine and Isoliensinine on 5α-Reductase / 中国药师

Objective:To compare the inhibitory effect of neferine and isoliensinine on 5α-reductase to provide reference for the development of 5α-reductase inhibitors. Methods: Different reaction tubes and control tubes were prepared, liver was homogenated, and reducing coenzyme II ( NADPH) , testosterone, pending test sample, the positive drug and buffer was respectively added into 96-well plates. The change in the absorbance of NADPH at 340nm in 1h was determined by a microplate reader. Compared the experimen-tal group with the blank control group, the inhibition rate ( I%) of the test drugs against 5α-reductase was calculated. Results:As for the six concentration gradients (2-40 mg·ml-1 ) in the experiments, the best inhibitory concentration of neferine and isoliensinine was 10 mg·ml-1(I% =25.00 ±1.030% and 29.90 ±2.410%, respectively). Compared with the control group, neferine and isoliensi-nine showed significant inhibition against 5α-reductase (P<0. 05). Compared with the positive group at the same concentration (10 mg ·ml-1), the inhibition of neferine and isoliensinine was significantly lower (P<0. 05). The inhibition effect of isoliensinine was rel-atively better than that of neferine (P<0. 05). Conclusion:Neferine and isoliensininein have notable inhibitory effect on 5α-reduc-tase, which show certain application prospect in the treatment of prostatic hyperplasia in clinics.

UV-spectrophotometric screening of 5α-reductase inhibitors for benign prostatic hyperplasia treatment / 中国病理生理杂志

AIM: Tranditional methods of screening drugs for benign prostatic hyperplasia(BPH)requires senile male animals such as dogs or rats.It consumes a long time to get the results. Over-expression of type Ⅱ5α-reductase in prastate induces BPH.A fast and efficient screening model of type Ⅱ5α-reductase inhibitors for BPH was set up in this paper.METHODS:Microsomes were extracted from male Sprague-Dawley rat livers by gradient centrifugation.Type Ⅱ5α-reductase enzyme-catalyzed reaction was assayed by UV-spectrophotometry using testosterone as a substrate and NADPH as hydrogen donor.The change of enzymatic activity was recorded with a NADPH wavelength of 340 nm by subtracted descending velocity of the control(without 5α-reductase).Effects at different conditions(temperatures,pH,enzyme and testosterone concentrations)on 5α-reductase were assayed.RESULTS:The suitable condition of type Ⅱ5α-reductase reaction Was defined as concentration of 109.05 mg protein/L enzyme(pH 6.00)with 2 μmol/L testosterone at 37℃.Michaelis'constant of type Ⅱ5α-reductase was 0.6μmol/L.Finasteride,a new drug for BPH,significantly inhibited activity of type Ⅱ 5α-reductase.IC50 of finasteride Was 64.1 nmol/L.As solvent of drugs,concentration of ethanol below 1.1% did not inhibite enzymatic activity(P＞0.05).Concentration of ethanol above 1.6%could obviouslv suppress enzymatic activity(P＜0.01).Daytime difference within five days had no significant difference(P＞0.05).CONCLUSION:A handy and fast screening method for type Ⅱ 5α-reductase inhibitors has been set up using UV-spectrophotometry.It may be used to screening drugs for BPH treatment.

Effects of male sex hormones on gender identity,sexual behavior, and cognitive function / 中南大学学报(医学版)

Androgens, the male sex hormones, play an essential role in male sexual differentiation and development. However, the influence of these sex hormones extends beyond their roles in sexual differentiation and development. In many animal species, sex hormones have been shown to be essential for sexual differentiation of the brain during development and for maintaining sexually dimorphic behavior throughout life. The principals of sex determination in humans have been demonstrated to be similar to other mammals. However, the hormonal influence on sexual dimorphic differences in the nervous system in humans, sex differences in behaviors, and its correlations with those of other mammals is still an emerging field. In this review, the roles of androgens in gender and cognitive function are discussed with the emphasis on subjects with androgen action defects including complete androgen insensitivity due to androgen receptor mutations and 5α-reductase-2 deficiency syndromes due to 5α-reductase-2 gene mutations. The issue of the complex interaction of nature versus nurture is addressed.

Molecular Cloning of hSC2 Encoding 5α-reductase-like Protein

BACKGROUND: The human homologue of the SC2 gene from a human dermal papilla cell cDNA library has been isolated and designated hSC2. HSC2 protein also shares similarity with 5 -reductase, a protein important in testosterone metabolism. OBJECTIVE: Prior to knowing the functions of hSC2 in dermal papilla, we cloned it and analyzed its relative expression levels in adult tissues and cancer cell lines. METHODS: hSC2 was isolated from low abundant clones in dermal papilla cDNA library using cDNA array hibridization method. Full-length clone was sequenced and we studied its expression in different tissues by Northern blot hybridization. RESULTS: Sequence data reveals a single open reading frame, encoding a putative hydrophobic protein with a calculated molecular weight of 36 kDa. Its deduced amino acid sequences are almost 97.4% identical to t4ose of rat protein. Northern blot hybridization shows that hSC2 cDNA recognizes a 1.35 kb transcript that was expressed in various epithelial and mesenchymal tissues including testis and liver. CONCLUSION: We have cloned and analysed tissue distributions of hSC2. It was interesting that it had homology with 5α-reductase isozymes. Further studies will be needed to understand the involvement of hSC2 in androgen hormone signaling.