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Akahane T, Kaya D, Noguchi R, Kaji K, Miyakawa H, Fujinaga Y, Tsuji Y, Takaya H, Sawada Y, Furukawa M, Kitagawa K, Ozutsumi T, Kawaratani H, Moriya K, Namisaki T, Yoshiji H. Association between Equol Production Status and Nonalcoholic Steatohepatitis. Int J Mol Sci 2021; 22:ijms222111904. [PMID: 34769332 PMCID: PMC8585044 DOI: 10.3390/ijms222111904] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/30/2021] [Accepted: 10/30/2021] [Indexed: 11/16/2022] Open
Abstract
Equol is a metabolite of daidzein, a major soybean isoflavone with estrogenic and antioxidant activities. As the production of equol depends on the presence of certain members of the intestinal microflora, not all individuals can produce equol. We examined the relationship between NASH histological features and equol production. In an animal model, obese OLETF rats were intraperitoneally injected with a porcine serum to augment liver fibrogenesis. Equol-rich soy product, SE5-OH was orally administered during the experimental period. Treatment with SE5-OH markedly attenuated the development of liver fibrosis and expression of alpha-smooth muscle actin. In clinical research, 38 NAFLD patients (13 men and 25 women) were included. The degree of fibrosis and ballooning in equol-nonproducers was significantly higher than in equol-producers in women. The percentage of nonproducers with NAFLD activity score (NAS) ≥ 5 was significantly higher than that of producers. None of the histological features were significantly different between nonproducers and producers in men. Decision tree analysis identified predictors for NAS ≥ 5 in women. The status of equol production was the strongest predictor, followed by fasting glucose. Since equol can be noninvasively detected in urine, it can be applied as a screening tool for the progression of NASH in women.
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Affiliation(s)
- Takemi Akahane
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
- Correspondence: ; Tel.: +81-744-22-3051
| | - Daisuke Kaya
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Ryuichi Noguchi
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Kosuke Kaji
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Haruna Miyakawa
- Saga Nutraceuticals Research Institute, Otsuka Pharmaceutical Co., Ltd., Saga 842-0195, Japan;
| | - Yukihisa Fujinaga
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Yuki Tsuji
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Hiroaki Takaya
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Yasuhiko Sawada
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Masanori Furukawa
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Koh Kitagawa
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Takahiro Ozutsumi
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Hideto Kawaratani
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Kei Moriya
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Tadashi Namisaki
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
| | - Hitoshi Yoshiji
- Department of Gastroenterology, Nara Medical University, Kashihara 634-8521, Japan; (D.K.); (R.N.); (K.K.); (Y.F.); (Y.T.); (H.T.); (Y.S.); (M.F.); (K.K.); (T.O.); (H.K.); (K.M.); (T.N.); (H.Y.)
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Gómez-Zorita S, González-Arceo M, Fernández-Quintela A, Eseberri I, Trepiana J, Portillo MP. Scientific Evidence Supporting the Beneficial Effects of Isoflavones on Human Health. Nutrients 2020; 12:nu12123853. [PMID: 33348600 PMCID: PMC7766685 DOI: 10.3390/nu12123853] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/14/2020] [Accepted: 12/15/2020] [Indexed: 12/11/2022] Open
Abstract
Isoflavones are phenolic compounds with a chemical structure similar to that of estradiol. They are present in several vegetables, mainly in legumes such as soy, white and red clover, alfalfa and beans. The most significant food source of isoflavones in humans is soy-derived products. Isoflavones could be used as an alternative therapy for pathologies dependent on hormonal disorders such as breast and prostate cancer, cardiovascular diseases, as well as to minimize menopausal symptoms. According to the results gathered in the present review, it can be stated that there is scientific evidence showing the beneficial effect of isoflavones on bone health and thus in the prevention and treatment of osteoporosis on postmenopausal women, although the results do not seem entirely conclusive as there are discrepancies among the studies, probably related to their experimental designs. For this reason, the results should be interpreted with caution, and more randomized clinical trials are required. By contrast, it seems that soy isoflavones do not lead to a meaningful protective effect on cardiovascular risk. Regarding cancer, scientific evidence suggests that isoflavones could be useful in reducing the risk of suffering some types of cancer, such as breast and endometrial cancer, but further studies are needed to confirm these results. Finally, isoflavones could be useful in reducing hot flushes associated with menopause. However, a limitation in this field is that there is still a great heterogeneity among studies. Lastly, with regard to isoflavone consumption safety, it seems that they are safe and that the most common adverse effect is mild and occurs at the gastrointestinal level.
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Affiliation(s)
- Saioa Gómez-Zorita
- Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; (S.G.-Z.); (M.G.-A.); (A.F.-Q.); (M.P.P.)
- CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, 01006 Vitoria, Spain
- Bioaraba Health Research Institute, 01002 Vitoria, Spain
| | - Maitane González-Arceo
- Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; (S.G.-Z.); (M.G.-A.); (A.F.-Q.); (M.P.P.)
| | - Alfredo Fernández-Quintela
- Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; (S.G.-Z.); (M.G.-A.); (A.F.-Q.); (M.P.P.)
- CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, 01006 Vitoria, Spain
- Bioaraba Health Research Institute, 01002 Vitoria, Spain
| | - Itziar Eseberri
- Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; (S.G.-Z.); (M.G.-A.); (A.F.-Q.); (M.P.P.)
- CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, 01006 Vitoria, Spain
- Bioaraba Health Research Institute, 01002 Vitoria, Spain
- Correspondence: (I.E.); (J.T.)
| | - Jenifer Trepiana
- Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; (S.G.-Z.); (M.G.-A.); (A.F.-Q.); (M.P.P.)
- CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, 01006 Vitoria, Spain
- Bioaraba Health Research Institute, 01002 Vitoria, Spain
- Correspondence: (I.E.); (J.T.)
| | - María Puy Portillo
- Nutrition and Obesity Group, Department of Pharmacy and Food Science, University of the Basque Country (UPV/EHU) and Lucio Lascaray Research Institute, 01006 Vitoria, Spain; (S.G.-Z.); (M.G.-A.); (A.F.-Q.); (M.P.P.)
- CIBEROBN Physiopathology of Obesity and Nutrition, Institute of Health Carlos III, 01006 Vitoria, Spain
- Bioaraba Health Research Institute, 01002 Vitoria, Spain
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Liu ZM, Ho SC, Chen YM, Xie YJ, Huang ZG, Ling WH. Research protocol: effect of natural S-equol on blood pressure and vascular function--a six-month randomized controlled trial among equol non-producers of postmenopausal women with prehypertension or untreated stage 1 hypertension. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 16:89. [PMID: 26928904 PMCID: PMC4772692 DOI: 10.1186/s12906-016-1065-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 02/23/2016] [Indexed: 11/10/2022]
Abstract
BACKGROUND Although higher habitual soy intake is associated with lower blood pressure (BP) and stroke incidence, clinical trials using soy protein or isoflavones on cardiovascular risks yielded inconsistent results. The discrepancies are hypothesized to be due to the individuals' intestinal bacterial capacity to metabolite isoflavones daidzein into equol. Animal and in vitro studies have revealed that equol has stronger estrogen-like and anti-oxidative activity than isoflavones and possesses natriuretic and vasorelaxant properties which may play an important role in the prevention of hypertension. However, no clinical trial has examined the effect of equol on BP. We thus propose a 24-week randomized controlled trial to test the effectiveness of natural S-equol on BP and vascular function among equol non-producers. METHODS/DESIGN This will be a 6-month double-blind, randomized, placebo-controlled trial among 207 non-equol producing postmenopausal women with prehypertension or early untreated hypertension. Eligible participants who have completed a 2-week run-in will be randomized to either one of the 3 groups: placebo group, low-equol group (10 mg/d) and high equol group (20 mg/d). The outcome measures will be conducted at baseline and at the end of the trial including 24 h ambulatory BP, endothelial function (by ultrasound determined brachial flow mediated dilation), arterial stiffness (by pulse wave analysis) and other cardiovascular risk factors (lipid profile, glycemic control and inflammatory biomarkers). Urinary isoflavones will be tested for compliance assessment. One way analysis of variance will be applied to compare the 6-month changes in ambulatory BP or parameters of vascular function among the 3 treatment groups. DISCUSSION This study will be performed in community subjects. If the antihypertensive effect of equol is proven, the provision of natural equol to those high risk adults who are unable to produce equol will have enormous public health implications for the primary and secondary prevention of hypertension and cardiovascular diseases on a population basis. The research efforts will also have significant implications for industry in the provision of suitable soy products for the prevention of hypertension and its related complications. TRIAL REGISTRATION The trial was registered in ClinicalTrials.gov with identifier of NCT02515682 .
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Affiliation(s)
- Zhao-min Liu
- Division of Family Medicine and Primary Care, The Jockey Club School of Public Health and Primary Care, the Chinese University of Hong Kong, Hong Kong, SAR.
| | - Suzanne C Ho
- Division of Epidemiology, The Jockey Club School of Public Health and Primary Care, the Chinese University of Hong Kong, Hong Kong, SAR
| | - Yu-ming Chen
- Department of Medical Statistics and Epidemiology, School of Public Health, Sun Yat-sen University, Guangzhou, PR China
| | - Yao Jie Xie
- School of Nursing, Faculty of Health and Social Science, the Hong Kong Polytechnic University, Hong Kong, SAR
| | - Zhi-guan Huang
- Department of Sport and Health, Guangzhou Sport University, Guangzhou, PR China.
| | - Wen-hua Ling
- Department of Nutrition, School of Public Health, Sun Yat-sen University, Guangzhou, PR China
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Mahalingam S, Gao L, Gonnering M, Helferich W, Flaws JA. Equol inhibits growth, induces atresia, and inhibits steroidogenesis of mouse antral follicles in vitro. Toxicol Appl Pharmacol 2016; 295:47-55. [PMID: 26876617 DOI: 10.1016/j.taap.2016.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 02/08/2016] [Accepted: 02/09/2016] [Indexed: 01/15/2023]
Abstract
Equol is a non-steroidal estrogen metabolite produced by microbial conversion of daidzein, a major soy isoflavone, in the gut of some humans and many animal species. Isoflavones and their metabolites can affect endogenous estradiol production, action, and metabolism, potentially influencing ovarian follicle function. However, no studies have examined the effects of equol on intact ovarian antral follicles, which are responsible for sex steroid synthesis and further development into ovulatory follicles. Thus, the present study tested the hypothesis that equol inhibits antral follicle growth, increases follicle atresia, and inhibits steroidogenesis in the adult mouse ovary. To test this hypothesis, antral follicles isolated from adult CD-1 mice were cultured with vehicle control (dimethyl sulfoxide; DMSO) or equol (600 nM, 6 μM, 36 μM, and 100 μM) for 48 and 96 h. Every 24h, follicle diameters were measured to monitor growth. At 48 and 96 h, the culture medium was subjected to measurement of hormone levels, and the cultured follicles were subjected to gene expression analysis. Additionally, follicles were histologically evaluated for signs of atresia after 96 h of culture. The results indicate that equol (100 μM) inhibited follicle growth, altered the mRNA levels of bcl2-associated X protein and B cell leukemia/lymphoma 2, and induced follicle atresia. Further, equol decreased the levels of estradiol, testosterone, androstenedione, and progesterone, and it decreased mRNA levels of cholesterol side-chain cleavage, steroid 17-α-hydroxalase, and aromatase. Collectively, these data indicate that equol inhibits growth, increases atresia, and inhibits steroidogenesis of cultured mouse antral follicles.
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Affiliation(s)
- Sharada Mahalingam
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802, United States.
| | - Liying Gao
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802, United States.
| | - Marni Gonnering
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802, United States.
| | - William Helferich
- Department of Food Science and Human Nutrition, University of Illinois, 905 S. Goodwin, Urbana, IL 61801, United States.
| | - Jodi A Flaws
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois, 2001 S. Lincoln Ave, Urbana, IL 61802, United States.
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The role of colonic bacteria in the metabolism of the natural isoflavone daidzin to equol. Metabolites 2015; 5:56-73. [PMID: 25594250 PMCID: PMC4381290 DOI: 10.3390/metabo5010056] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 01/07/2015] [Indexed: 12/18/2022] Open
Abstract
Isoflavones are found in leguminous plants, especially soybeans. They have a structural similarity to natural estrogens, which enables them to bind to estrogen receptors and elicit biological activities similar to natural estrogens. They have been suggested to be beneficial for the prevention and therapy of hormone-dependent diseases. After soy products are consumed, the bacteria of the intestinal microflora metabolize isoflavones to metabolites with altered absorption, bioavailability, and estrogenic characteristics. Variations in the effect of soy products have been correlated with the isoflavone metabolites found in plasma and urine samples of the individuals consuming soy products. The beneficial effects of the soy isoflavone daidzin, the glycoside of daidzein, have been reported in individuals producing equol, a reduction product of daidzein produced by specific colonic bacteria in individuals called equol producers. These individuals comprise 30% and 60% of populations consuming Western and soy-rich Asian diets, respectively. Since the higher percentage of equol producers in populations consuming soy-rich diets is correlated with a lower incidence of hormone-dependent diseases, considerable efforts have been made to detect the specific colonic bacteria involved in the metabolism of daidzein to the more estrogenic compound, equol, which should facilitate the investigation of the metabolic activities related to this compound.
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Affiliation(s)
- Shigeto Uchiyama
- Otsuka Pharmaceutical Co., Ltd., Saga Nutraceuticals Research Institute
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Ueno T, Abiru Y, Uchiyama S, Ishimi Y. Distribution of 24-h urinary equol excretion as an indicator of the physiological range in healthy Japanese equol excretors. J Funct Foods 2014. [DOI: 10.1016/j.jff.2013.12.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Usui T, Tochiya M, Sasaki Y, Muranaka K, Yamakage H, Himeno A, Shimatsu A, Inaguma A, Ueno T, Uchiyama S, Satoh-Asahara N. Effects of natural S-equol supplements on overweight or obesity and metabolic syndrome in the Japanese, based on sex and equol status. Clin Endocrinol (Oxf) 2013; 78:365-72. [PMID: 22469418 DOI: 10.1111/j.1365-2265.2012.04400.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 01/18/2012] [Accepted: 03/29/2012] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Epidemiologic studies indicate that soy intake has an important role in the prevention of age-related health problems. Daidzein, the principal isoflavone contained in soy, is converted to S-equol by the intestinal bacteria. Not all individuals, however, can produce S-equol, which is considered the most biologically active metabolite. We studied the effects of a natural S-equol supplement on metabolic parameters associated with overweight or obesity and metabolic syndrome. METHODS The study was a randomized, double-blinded, placebo-controlled, crossover design with no washout period. All subjects were considered overweight or obese if they had a body mass index ≥ 25 kg/m(2) . Placebo or natural S-equol tablets containing 10 mg S-equol were orally ingested each day for 12 weeks. A total of 54 Japanese overweight or obese outpatients were enrolled. The equol phenotype was determined, and various metabolic parameters, including cardio-ankle vascular index (CAVI), were measured. RESULTS Equol non-producers comprised 67.9% of the overweight or obese subjects. The ratio of equol non-producers in this overweight or obese subject group was higher than the previously reported ratio of equol non-producers (approximately 50%) in the general population. Compared with the placebo group, intervention with natural S-equol led to a significant decrease in HbA1c, serum low-density lipoprotein cholesterol (LDL-C) levels and CAVI score. Furthermore, the effect was more prominent in the subgroup of female equol non-producers. CONCLUSION The ratio of equol non-producers in overweight or obese populations might be higher than generally reported. Natural S-equol might have a role in glycaemic control and in the prevention of cardiovascular disease by its effects to lower LDL-C levels and CAVI scores in overweight or obese individuals.
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Affiliation(s)
- Takeshi Usui
- Clinical Research Institute, National Hospital Organization, Kyoto Medical Center, Kyoto, Japan.
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Dewi FN, Wood CE, Lampe JW, Hullar MAJ, Franke AA, Golden DL, Adams MR, Cline JM. Endogenous and exogenous equol are antiestrogenic in reproductive tissues of apolipoprotein e-null mice. J Nutr 2012; 142:1829-35. [PMID: 22933749 PMCID: PMC3442795 DOI: 10.3945/jn.112.161711] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 05/01/2012] [Accepted: 07/25/2012] [Indexed: 02/05/2023] Open
Abstract
Equol is an isoflavone (IF) metabolite produced by intestinal microbiota in a subset of people consuming dietary soy. Equol producers may show different responses to soy foods and phenotypes related to cancer risk. Here, we assessed the effects of soy IF, endogenous microbial equol production, and dietary racemic equol in a 3 × 2 × 2 factorial experiment using gnotobiotic apoE-null mice (n = 9-11/group/sex). At age 3-6 wk, equol-producing microbiota were introduced to one-half of the colony (n = 122). At age 6 wk, mice were randomized to receive a diet that contained 1 of 3 protein sources: casein and lactalbumin, alcohol-washed soy protein (low IF), and intact soy protein (high IF), with total IF amounts of 0, 42, and 566 mg/kg diet, respectively. One-half of each diet group also received racemic equol (291 mg/kg diet). After 16 wk of dietary treatment, serum isoflavonoid profiles varied with sex, soy IF amount, and intestinal microbiota status. There were no treatment effects on tissues of male mice. In females, reproductive tissue phenotypes differed by equol-producing ability (i.e., microbiota status) but not dietary equol or IF content. Equol producers had lower uterine weight, vaginal epithelial thickness, total uterine area, endometrial area, and endometrial luminal epithelial height compared with nonproducers (P < 0.05 for all), with an association between microbiota status and estrous cycle (P > chi-square = 0.03). Exogenous equol reduced expression of progesterone receptor (PGR) and the proliferation marker Ki67 (P < 0.0001) in vaginal epithelium and endometrium; for endogenous equol, only PGR was reduced (P < 0.0005). Our findings indicate that equol diminishes estrogen-dependent tissue responses in apoE-null mice.
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Affiliation(s)
- Fitriya N. Dewi
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston Salem, NC
| | - Charles E. Wood
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston Salem, NC
| | | | | | - Adrian A. Franke
- Cancer Biology Program, University of Hawaii Cancer Center, Honolulu, HI
| | - Deborah L. Golden
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston Salem, NC
| | - Michael R. Adams
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston Salem, NC
| | - J. Mark Cline
- Department of Pathology, Section on Comparative Medicine, Wake Forest School of Medicine, Winston Salem, NC
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The effects of natural S-equol supplementation on skin aging in postmenopausal women: a pilot randomized placebo-controlled trial. Menopause 2012; 19:202-10. [PMID: 21934634 DOI: 10.1097/gme.0b013e318227427b] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the effects of the natural S-equol supplement on skin aging in equol-nonproducing Japanese postmenopausal women. METHODS A randomized, double-blind, placebo-controlled trial examined the use of the natural S-equol supplement for 12 weeks in 101 postmenopausal Japanese women who were equol nonproducers. They were randomly assigned to one of three groups: placebo (n = 34), 10 mg S-equol/day (EQL10; n = 34), or 30 mg S-equol/day (EQL30; n = 33). Skin parameters of crow's-feet wrinkles (area and depth), hydration, transepidermal water loss, and elasticity were measured at baseline and at monthly intervals during treatment. Vaginal cytology, endometrial thickness, and mammography were performed before and after treatment. Serum hormone concentrations were measured at the same time as skin parameters. RESULTS The EQL10 and EQL30 groups showed significant reductions in wrinkle area compared with the placebo group (P < 0.05). There was a significant difference in wrinkle depth between the placebo group and the EQL30 group (P < 0.05). Other skin parameters did not show significant differences after the treatment in any group. There were no abnormal results in hormone status or gynecological examinations. CONCLUSIONS Our data suggest that natural S-equol supplementation (EQL10 and EQL30) may have a beneficial effect on crow's-feet wrinkles in postmenopausal women without serious adverse events.
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Onoda A, Ueno T, Uchiyama S, Hayashi SI, Kato K, Wake N. Effects of S-equol and natural S-equol supplement (SE5-OH) on the growth of MCF-7 in vitro and as tumors implanted into ovariectomized athymic mice. Food Chem Toxicol 2011; 49:2279-84. [PMID: 21703324 DOI: 10.1016/j.fct.2011.06.027] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Revised: 06/09/2011] [Accepted: 06/10/2011] [Indexed: 12/23/2022]
Abstract
Hormone replacement therapy (HRT) for treatment of menopausal symptoms is controversial because of reported breast cancer resulting from estrogen treatment and consequent estrogenic stimulation. S-equol, a natural metabolite of the soy isoflavone daidzein produced by intestinal bacteria, has been shown to ameliorate menopausal symptoms, with relatively low concomitant estrogenic receptor stimulation. Although synthesis of equol produces the racemate, the S-isomer may be produced in commercial amounts by bacterial fermentation of soy germ, during the production of the supplement SE5-OH. This study aims to investigate the effects of S-equol and SE5-OH on the growth of MCF-7 in vitro and in vivo. In vitro, purified S-equol, and the isoflavonoid mixture present in SE5-OH stimulated estrogenic transcriptional activity and proliferation of MCF-7-E10 cells, similar to that observed for genistein (another soy isoflavone), but at concentrations from 10(4)-fold to 10(6)-fold higher than seen with 17β-estradiol (E2). Ovariectomized (OVX) mice implanted with MCF-7-E10 cells were fed diets containing 250 or 500 ppm of purified S-equol, isoflavonoid mixture, or genistein. There were no significant differences in tumor growth between the treatment groups and control group. These results suggest that S-equol and natural S-equol in the supplement (SE5-OH), do not promote the progression of breast cancer.
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Affiliation(s)
- Atsuko Onoda
- Saga Nutraceuticals Research Institute, Otsuka Pharmaceutical Co., Ltd., 5006-5 Yoshinogari-cho, Kanzaki-gun, Saga 842-0195, Japan.
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Impact of perinatal exposure to equol enantiomers on reproductive development in rodents. Reprod Toxicol 2011; 32:33-42. [PMID: 21620954 DOI: 10.1016/j.reprotox.2011.05.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 04/15/2011] [Accepted: 05/12/2011] [Indexed: 11/22/2022]
Abstract
There is now considerable interest in the intestinally derived soy isoflavone metabolite, equol, which occurs in the enantiomeric forms, S-(-)equol and R-(+)equol, both differing in biological actions. Little is known about effects of either enantiomer on reproductive development, yet such knowledge is fundamental because of the recent commercialization of S-(-)equol as a dietary supplement. S-(-)equol and R-(+)equol were therefore investigated to determine their effects on reproductive development and fertility in the Sprague-Dawley rat. Neither enantiomer affected fertility, number of litters produced, number of pups per litter, number of male and female pups born, birth weight, anogenital distance, testicular descent or vaginal opening. Histological analysis showed no major abnormalities in ovary, testis, prostate or seminal vesicle tissue with dietary exposure to S-(-)equol or R-(+)equol, but both enantiomers triggered hyperplasia of uterine tissue. With R-(+)equol this stimulatory effect subsided after exposure was discontinued, but the effect of S-(-)equol was prolonged.
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Natural S-equol decreases bone resorption in postmenopausal, non-equol-producing Japanese women. Menopause 2011; 18:563-74. [DOI: 10.1097/gme.0b013e3181f85aa7] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bonacasa B, Siow RCM, Mann GE. Impact of dietary soy isoflavones in pregnancy on fetal programming of endothelial function in offspring. Microcirculation 2011; 18:270-85. [PMID: 21418378 DOI: 10.1111/j.1549-8719.2011.00088.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Epidemiological evidence suggests that soy-based diets containing phytoestrogens (isoflavones) afford protection against cardiovascular diseases (CVDs); however, supplementation trials have largely reported only marginal health benefits. The molecular mechanisms by which the isoflavones genistein, daidzein, and equol afford protection against oxidative stress remain to be investigated in large scale clinical trials. Isoflavones are transferred across the placenta in both rodents and humans, yet there is limited information on their actions in pregnancy and the developmental origins of disease. Our studies established that feeding a soy isoflavone-rich diet during pregnancy, weaning, and postweaning affords cardiovascular protection in aged male rats. Notably, rats exposed to a soy isoflavone-deficient diet throughout pregnancy and adult life exhibited increased oxidative stress, diminished antioxidant enzyme and eNOS levels, endothelial dysfunction, and elevated blood pressure in vivo. The beneficial effects of refeeding isoflavones to isoflavone-deficient rats include an increased production of nitric oxide and EDHF, an upregulation of antioxidant defense enzymes and lowering of blood pressure in vivo. This review focuses on the role that isoflavones in the fetal circulation may play during fetal development in affording protection against CVD in the offspring via their ability to activate eNOS, EDHF, and redox-sensitive gene expression.
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Affiliation(s)
- Barbara Bonacasa
- Cardiovascular Division, British Heart Foundation Centre of Research Excellence, School of Medicine, King's College London, London, UK
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Abstract
It has been well documented that the frequency of vasomotor menopausal symptoms, such as hot flashes and night sweats, of Japanese menopausal women is less than that of Western women. High intake of soy isoflavones in the traditional Japanese diet has been postulated as the possible explanation of the difference. Epidemiological studies have reported that the content of equol, which is a biologically active metabolite of the isoflavone, daidzein, is lower in the women who complain of severe vasomotor symptoms. To investigate the involvement of equol in the manifestation of menopausal symptoms, especially vasomotor symptoms, and the possible therapeutic role of a supplement containing equol (natural S-equol developed by Otsuka Pharmaceutical) on the menopausal symptoms of Japanese women, 3 randomized clinical trials were conducted. The studies indicated that a daily dose of 10 mg of natural S-equol improved menopausal symptoms. In the confirmation study, menopausal women who were equol nonproducers who consumed 10 mg/d of natural S-equol for 12 wk had significantly reduced severity and frequency of hot flashes as well as a significant reduction in the severity of neck or shoulder stiffness. The equol-ingesting group also showed trends of improvement in sweating and irritability and a significant improvement in the somatic category symptoms. Thus, it is concluded that the supplement containing natural S-equol, a novel soybean-derived functional component, has a promising role as an alternative remedy in the management of menopausal symptoms.
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Affiliation(s)
- Takeshi Aso
- Comprehensive Reproductive Medicine, Tokyo Medical and Dental University, Tokyo 113-8519, Japan.
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