The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis ...The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis microsomes. These enzymes （3β-HSD and 17β-HSD3）, along with two others （cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase）, catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. Genistein inhibited 3β-HSD activity （0.2 μmol L^-1 pregnenolone） with half-maximal inhibition or a half-maximal inhibitory concentration （IC50） of 87 ± 15 （human） and 636 ± 155 nmol L^-1 （rat）. Genistein＇s mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD＋. There was no difference in genistein＇s potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 （0.1 μmol L^-1 androstenedione）, with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. These observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.展开更多
Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activitie...Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activities.Methods Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS–MS,and human aromatase activity was determined by radioimmunoassay.Results PFSA inhibited human 3β-HSD1 structure-dependently in the order:perfluorooctanesulfonic acid(PFOS,half-maximum inhibitory concentration,IC50:9.03±4.83μmol/L)>perfluorodecanesulfonic acid(PFDS,42.52±8.99μmol/L)>perfluoroheptanesulfonic acid(PFHpS,112.6±29.39μmol/L)>perfluorobutanesulfonic acid(PFBS)=perfluoropentanesulfonic acid(PFPS)=perfluorohexanesulfonic acid(PFHxS)=perfluorododecanesulfonic acid(PFDoS)(ineffective at 100μmol/L).6:2FTS(1H,1H,2H,2H-perfluorooctanesulfonic acid)and 8:2FTS(1H,1H,2H,2H-perfluorodecanesulfonic acid)did not inhibit human 3β-HSD1.PFOS and PFHpS are mixed inhibitors,whereas PFDS is a competitive inhibitor.Moreover,1–10μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 cells.Docking analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent manner.All 100μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase activity.Conclusion Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS(C8),with inhibitory potency of PFOS>PFDS>PFHpS>PFBS=PFPS=PFHxS=PFDoS=6:2FTS=8:2FTS.展开更多
Objective:To evaluate the effect of methanolic extract and ethyl acetate fraction of methanol extract prepared from the seeds of Blepharis(B.)persica on testosterone biosynthesis and also to elucidate the underlying m...Objective:To evaluate the effect of methanolic extract and ethyl acetate fraction of methanol extract prepared from the seeds of Blepharis(B.)persica on testosterone biosynthesis and also to elucidate the underlying mechanism.Methods:Forty-eight male Wistar rats were divided into eight groups(n=6 per group).GroupⅠreceived 0.3%w/w gum acacia suspension p.o.and served as the normal control group.GroupⅡwas administered testosterone propionate in arachis oil i.m.as the positive control group.GroupⅢtoⅣreceived B.persica methanolic extract p.o.at doses of 50,100 and 200 mg/kg body weight.GroupⅥtoⅦreceived B.persica ethyl acetate fraction p.o.at doses of 50,100 and 200 mg/kg body weight.The testis was used for biochemical estimation and histological studies.The effects of methanolic extract and ethyl acetate fraction of B.persica on testicular testosterone,mRNA expression corresponding to steroidogenic acute regulatory protein(StAR)and 3β-hydroxysteroid dehydrogenase(3β-HSD)along with 3β-HSD enzyme assay were evaluated in testicular tissues and sperm concentration.Ethyl acetate fraction of B.persica was subjected to column chromatography.Invitro studies were performed using TM3 cell line at three dose levels(50,100,200μg/mL),each for methanolic extract,ethyl acetate fraction and 2-benzoxazolinone for evaluation of their comparative effect on testosterone production.Results:Ethyl acetate fraction and methanolic extract of B.persica could elevate the testicular testosterone content compared to the normal control group.The treatment with methanolic extract and ethyl acetate fraction of B.persica increased the expression of mRNA corresponding to StAR by 6.7 fold and 10.6 fold,respectively,whereas the mRNA expression of 3β-HSD increased by 5.7 fold and 7.3 fold,respectively.Moreover,fraction and extract treatment exhibited increased 3β-HSD activity in the testicular tissues and were found to elevate sperm concentration in seminal fluid.The spermatogenic potential was further ensured by histological observations.2-benzoxazolinone was isolated from ethyl acetate fraction and identified using spectral studies.It showed the ability to increase the testosterone content in the TM3 Leydig cells.Conclusions:Methanolic extract and ethyl acetate fraction of B.persica are able to increase the testicular testosterone in rats by elevating mRNA expression of StAR and 3β-HSD in testicular tissues,leading to increase the sperm concentration.展开更多
17β-hydroxysteroid dehydrogenase(17β-HSD)type 1 is known as a critical target to block the final step of estrogen production in estrogen-dependent breast cancer.Recent confirmation of the role of dyhydroxytestostero...17β-hydroxysteroid dehydrogenase(17β-HSD)type 1 is known as a critical target to block the final step of estrogen production in estrogen-dependent breast cancer.Recent confirmation of the role of dyhydroxytestosterone(DHT)in counteracting estrogeninduced cell growth prompted us to study the reductive 17β-HSD type 7(17β-HSD7),which activates estrone while markedly inactivatingDHT.The role ofDHTin breast cancer cell proliferation isdemonstratedby its independent suppression of cell growthin the presence of a physiological concentration of estradiol(E2).Moreover,an integral analysis of a large number of clinical samples in Oncomine datasets demonstrated the overexpression of 17β-HSD7 in breast carcinoma.Inhibition of 17β-HSD7 in breast cancer cells resulted in a lower level of E2 and a higher level of DHT,successively induced regulation of cyclinD1,p21,Bcl-2,and Bik,consequently arrested cell cycle in the G0/G1 phase,and triggered apoptosis and auto-downregulation feedback of the enzyme.Such inhibition led to significant shrinkage of xenograft tumors with decreased cancer cell density and reduced 17β-HSD7 expression.Decreased plasma E2 and elevated plasma DHT levels were also found.Thus,the dual functional 17β-HSD7 is proposed as a novel target for estrogen-dependent breast cancer by regulating the balance of E2 andDHT.Thisdemonstrates aconceptual advance on the general belief that the major role of this enzyme is in cholesterol metabolism.展开更多
文摘The objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis microsomes. These enzymes （3β-HSD and 17β-HSD3）, along with two others （cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase）, catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. Genistein inhibited 3β-HSD activity （0.2 μmol L^-1 pregnenolone） with half-maximal inhibition or a half-maximal inhibitory concentration （IC50） of 87 ± 15 （human） and 636 ± 155 nmol L^-1 （rat）. Genistein＇s mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD＋. There was no difference in genistein＇s potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 （0.1 μmol L^-1 androstenedione）, with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. These observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.
文摘Objective This study aimed to compare 9 perfluoroalkyl sulfonic acids(PFSA)with carbon chain lengths(C4–C12)to inhibit human placental 3β-hydroxysteroid dehydrogenase 1(3β-HSD1),aromatase,and rat 3β-HSD4 activities.Methods Human and rat placental 3β-HSDs activities were determined by converting pregnenolone to progesterone and progesterone secretion in JEG-3 cells was determined using HPLC/MS–MS,and human aromatase activity was determined by radioimmunoassay.Results PFSA inhibited human 3β-HSD1 structure-dependently in the order:perfluorooctanesulfonic acid(PFOS,half-maximum inhibitory concentration,IC50:9.03±4.83μmol/L)>perfluorodecanesulfonic acid(PFDS,42.52±8.99μmol/L)>perfluoroheptanesulfonic acid(PFHpS,112.6±29.39μmol/L)>perfluorobutanesulfonic acid(PFBS)=perfluoropentanesulfonic acid(PFPS)=perfluorohexanesulfonic acid(PFHxS)=perfluorododecanesulfonic acid(PFDoS)(ineffective at 100μmol/L).6:2FTS(1H,1H,2H,2H-perfluorooctanesulfonic acid)and 8:2FTS(1H,1H,2H,2H-perfluorodecanesulfonic acid)did not inhibit human 3β-HSD1.PFOS and PFHpS are mixed inhibitors,whereas PFDS is a competitive inhibitor.Moreover,1–10μmol/L PFOS and PFDS significantly reduced progesterone biosynthesis in JEG-3 cells.Docking analysis revealed that PFSA binds to the steroid-binding site of human 3β-HSD1 in a carbon chain length-dependent manner.All 100μmol/L PFSA solutions did not affect rat 3β-HSD4 and human placental aromatase activity.Conclusion Carbon chain length determines inhibitory potency of PFSA on human placental 3β-HSD1 in a V-shaped transition at PFOS(C8),with inhibitory potency of PFOS>PFDS>PFHpS>PFBS=PFPS=PFHxS=PFDoS=6:2FTS=8:2FTS.
基金supported by Charotar University of Science and Technology through CHARUSAT Research Grant sanctioned to Dr.Manan Raval[CHARUSAT SEED RESEARCH GRANT/RPCP/MAR/12].
文摘Objective:To evaluate the effect of methanolic extract and ethyl acetate fraction of methanol extract prepared from the seeds of Blepharis(B.)persica on testosterone biosynthesis and also to elucidate the underlying mechanism.Methods:Forty-eight male Wistar rats were divided into eight groups(n=6 per group).GroupⅠreceived 0.3%w/w gum acacia suspension p.o.and served as the normal control group.GroupⅡwas administered testosterone propionate in arachis oil i.m.as the positive control group.GroupⅢtoⅣreceived B.persica methanolic extract p.o.at doses of 50,100 and 200 mg/kg body weight.GroupⅥtoⅦreceived B.persica ethyl acetate fraction p.o.at doses of 50,100 and 200 mg/kg body weight.The testis was used for biochemical estimation and histological studies.The effects of methanolic extract and ethyl acetate fraction of B.persica on testicular testosterone,mRNA expression corresponding to steroidogenic acute regulatory protein(StAR)and 3β-hydroxysteroid dehydrogenase(3β-HSD)along with 3β-HSD enzyme assay were evaluated in testicular tissues and sperm concentration.Ethyl acetate fraction of B.persica was subjected to column chromatography.Invitro studies were performed using TM3 cell line at three dose levels(50,100,200μg/mL),each for methanolic extract,ethyl acetate fraction and 2-benzoxazolinone for evaluation of their comparative effect on testosterone production.Results:Ethyl acetate fraction and methanolic extract of B.persica could elevate the testicular testosterone content compared to the normal control group.The treatment with methanolic extract and ethyl acetate fraction of B.persica increased the expression of mRNA corresponding to StAR by 6.7 fold and 10.6 fold,respectively,whereas the mRNA expression of 3β-HSD increased by 5.7 fold and 7.3 fold,respectively.Moreover,fraction and extract treatment exhibited increased 3β-HSD activity in the testicular tissues and were found to elevate sperm concentration in seminal fluid.The spermatogenic potential was further ensured by histological observations.2-benzoxazolinone was isolated from ethyl acetate fraction and identified using spectral studies.It showed the ability to increase the testosterone content in the TM3 Leydig cells.Conclusions:Methanolic extract and ethyl acetate fraction of B.persica are able to increase the testicular testosterone in rats by elevating mRNA expression of StAR and 3β-HSD in testicular tissues,leading to increase the sperm concentration.
基金supported by operating grants from Canadian Institutes of Health Research(CIHR,MOP 97917 to S.-X.L.,D.P.,and C.J.D.MOP 89851 to S.-X.L.and D.P.)China Scholarship Council(PhD Fellowship,#2010621032 to X.Q.W.).
文摘17β-hydroxysteroid dehydrogenase(17β-HSD)type 1 is known as a critical target to block the final step of estrogen production in estrogen-dependent breast cancer.Recent confirmation of the role of dyhydroxytestosterone(DHT)in counteracting estrogeninduced cell growth prompted us to study the reductive 17β-HSD type 7(17β-HSD7),which activates estrone while markedly inactivatingDHT.The role ofDHTin breast cancer cell proliferation isdemonstratedby its independent suppression of cell growthin the presence of a physiological concentration of estradiol(E2).Moreover,an integral analysis of a large number of clinical samples in Oncomine datasets demonstrated the overexpression of 17β-HSD7 in breast carcinoma.Inhibition of 17β-HSD7 in breast cancer cells resulted in a lower level of E2 and a higher level of DHT,successively induced regulation of cyclinD1,p21,Bcl-2,and Bik,consequently arrested cell cycle in the G0/G1 phase,and triggered apoptosis and auto-downregulation feedback of the enzyme.Such inhibition led to significant shrinkage of xenograft tumors with decreased cancer cell density and reduced 17β-HSD7 expression.Decreased plasma E2 and elevated plasma DHT levels were also found.Thus,the dual functional 17β-HSD7 is proposed as a novel target for estrogen-dependent breast cancer by regulating the balance of E2 andDHT.Thisdemonstrates aconceptual advance on the general belief that the major role of this enzyme is in cholesterol metabolism.
