Equol is a metabolite of soybean isoflavone, daidzein, and many health benefits are expected. Endogenous equol in urine is S-equol and mostly exists as glucuronate or sulfate conjugate. In this study we preliminary es...Equol is a metabolite of soybean isoflavone, daidzein, and many health benefits are expected. Endogenous equol in urine is S-equol and mostly exists as glucuronate or sulfate conjugate. In this study we preliminary established the simple enzyme-linked immunosorbent assay (ELISA) without deconjugation, then developed the S-equol specific ELISA involves deconjugation showing high stereospecificity to S-equol without using stereospecific antibody. For the simple ELISA, we used a polyclonal antibody that targets the regions not influenced by inhibition by conjugation of glucuronate and sulfate and achieved the correlation coefficient;r = 0.975, but the value was 30 % lower than high performance liquid chromatography (HPLC). Developing upon this we invented the specific ELISA established from S-equol homogeneous combination for the standard and enzyme-labeled antigen to enhance stereospecificity. The correlation with HPLC was favorable: r = 0.986, y = 0.996x – 6. Compared to the previous method using (R,S)-equol combination, cross-reactivity with R-equol was reduced from 65 to 13 %, and that with daidzein from 0.31% to 0.08%, markedly increased in the specificity. This study is expected to be applied for both simple clinical researches, and stereospecific immunoassays in which specific antibody preparation is difficult.展开更多
Natural products and their derivatives provide an attractive source for novel preventive and therapeutic agents.Epidemiological studies have indicated that the low incidence of breast cancer in Asian women may be rela...Natural products and their derivatives provide an attractive source for novel preventive and therapeutic agents.Epidemiological studies have indicated that the low incidence of breast cancer in Asian women may be related to a high consumption of soy foods.Equol,a metabolite of the soybean isoflavone daidzein,has been suggested to have preventive and therapeutic activity for breast cancer.However,conflicting data have been reported.There are two optical isomers of equol,S-equol and R-equol,with S-equol appearing to be the clinically-relevant compound.While equol is considered to be a selective estrogen receptor modulator,the molecular mechanisms underlying the biological activities of equol have not been fully elucidated.In addition,only part of the population can metabolize daidzein into equol due to differences in gut flora.This article will help provide a better understanding of the molecular mechanisms underlying the anti-(or potentially pro-)cancer and invasion activities of this unique secondary metabolite of a natural product,and will provide a basis for the development of equol and/or its analogs as novel cancer preventive or therapeutic agents.展开更多
Estrogen receptor beta(ERβ) is one of the two key receptors(ERα, ERβ) that facilitate biological actions of 17β-estradiol(E2). ERβ is widely expressed in many tissues, and its expression is reduced or lost during...Estrogen receptor beta(ERβ) is one of the two key receptors(ERα, ERβ) that facilitate biological actions of 17β-estradiol(E2). ERβ is widely expressed in many tissues, and its expression is reduced or lost during progression of many tumors. ERβ facilitates estrogen signaling by both genomic(classical and non-classical) and extra-nuclear signaling. Emerging evidence suggests that ERβ functions as a tissue-specific tumor suppressor with anti-proliferative actions. Recent studies have identified a number of naturally available selective ERβ agonists. Targeting ERβ using its naturally available ligands is an attractive approach for treating and preventing cancers. This review presents the beneficial actions of ERβ signaling and clinical utility of several natural ERβ ligands as potential cancer therapy.展开更多
文摘Equol is a metabolite of soybean isoflavone, daidzein, and many health benefits are expected. Endogenous equol in urine is S-equol and mostly exists as glucuronate or sulfate conjugate. In this study we preliminary established the simple enzyme-linked immunosorbent assay (ELISA) without deconjugation, then developed the S-equol specific ELISA involves deconjugation showing high stereospecificity to S-equol without using stereospecific antibody. For the simple ELISA, we used a polyclonal antibody that targets the regions not influenced by inhibition by conjugation of glucuronate and sulfate and achieved the correlation coefficient;r = 0.975, but the value was 30 % lower than high performance liquid chromatography (HPLC). Developing upon this we invented the specific ELISA established from S-equol homogeneous combination for the standard and enzyme-labeled antigen to enhance stereospecificity. The correlation with HPLC was favorable: r = 0.986, y = 0.996x – 6. Compared to the previous method using (R,S)-equol combination, cross-reactivity with R-equol was reduced from 65 to 13 %, and that with daidzein from 0.31% to 0.08%, markedly increased in the specificity. This study is expected to be applied for both simple clinical researches, and stereospecific immunoassays in which specific antibody preparation is difficult.
基金an NSFC grants from the National Natural Science Foundation of China(No.81171991)to Hong Xia XuNational Natural Science Foundation of China(No.81603347)to Zong Liang Lu.
文摘Natural products and their derivatives provide an attractive source for novel preventive and therapeutic agents.Epidemiological studies have indicated that the low incidence of breast cancer in Asian women may be related to a high consumption of soy foods.Equol,a metabolite of the soybean isoflavone daidzein,has been suggested to have preventive and therapeutic activity for breast cancer.However,conflicting data have been reported.There are two optical isomers of equol,S-equol and R-equol,with S-equol appearing to be the clinically-relevant compound.While equol is considered to be a selective estrogen receptor modulator,the molecular mechanisms underlying the biological activities of equol have not been fully elucidated.In addition,only part of the population can metabolize daidzein into equol due to differences in gut flora.This article will help provide a better understanding of the molecular mechanisms underlying the anti-(or potentially pro-)cancer and invasion activities of this unique secondary metabolite of a natural product,and will provide a basis for the development of equol and/or its analogs as novel cancer preventive or therapeutic agents.
基金supported by the NIH/NCI grant CA178499-01(RKV)CPRIT Training grant RP140105(GRS)2014-15 ABTA Discovery grant(GRS)
文摘Estrogen receptor beta(ERβ) is one of the two key receptors(ERα, ERβ) that facilitate biological actions of 17β-estradiol(E2). ERβ is widely expressed in many tissues, and its expression is reduced or lost during progression of many tumors. ERβ facilitates estrogen signaling by both genomic(classical and non-classical) and extra-nuclear signaling. Emerging evidence suggests that ERβ functions as a tissue-specific tumor suppressor with anti-proliferative actions. Recent studies have identified a number of naturally available selective ERβ agonists. Targeting ERβ using its naturally available ligands is an attractive approach for treating and preventing cancers. This review presents the beneficial actions of ERβ signaling and clinical utility of several natural ERβ ligands as potential cancer therapy.
