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Lipovac M, Pfitscher A, Hobiger S, Laschitz T, Imhof M, Chedraui P, Jungbauer A. Red clover isoflavone metabolite bioavailability is decreased after fructooligosaccharide supplementation. Fitoterapia 2015; 105:93-101. [PMID: 26073948 DOI: 10.1016/j.fitote.2015.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 06/09/2015] [Accepted: 06/10/2015] [Indexed: 12/01/2022]
Abstract
BACKGROUND Red clover is an important source of isoflavones; which has been made commercially available as dietary supplements for the treatment of menopausal symptoms. Bioavailability and metabolism of these red clover isoflavones (RCI) have not been studied in detail. Fructooligosaccharides (FOS) stimulate the growth of intestinal bacteria and play an important role in the formation of certain isoflavone metabolites, such as equol and O-desmethylangolensin. OBJECTIVE To determine the bioavailability of RCI metabolites and analyse whether FOS supplementation could influence their bioavailability. METHODS Seventeen healthy adults were enrolled in the study carried out in two periods. In the first, compound bioavailability was determined after consumption of 80 mg of RCI (MF11RCE). In the second, a 6-day supplementation of 2×3000 mg/day of FOS was administered before isoflavone consumption. RESULTS Biochanin A and formononetin were rapidly absorbed and both reached maximum concentrations at an average of 5-7h. Demethylation was a major reaction in the metabolic pathway. Daidzein serum level peaked after about 12.6h. Supplementation with FOS led to a significant decrease in the bioavailability of daidzein, dihydroformononetin, dihydrogenistein and dihydrodaidzein. An increase in equol production was also observed which did not reach statistical significance (p>0.05). CONCLUSION This study is the first to provide detailed data on RCI bioavailability in humans and determine no influence of FOS yet a trend toward increased equol production. More research is warranted involving a greater sample size.
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Affiliation(s)
- Markus Lipovac
- Karl Landsteiner Institute for cell-based therapy in Gynecology, Wiener Ring 3-5, 2100 Korneuburg, Austria
| | - Angelika Pfitscher
- Christian-Doppler-Laboratory of Receptor Biotechnology, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Applied Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Stefanie Hobiger
- Christian-Doppler-Laboratory of Receptor Biotechnology, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Applied Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
| | - Thomas Laschitz
- Department of Obstetrics and Gynecology General Public Teaching Hostpital of Korneuburg, Wiener Ring 3-5, 2100 Korneuburg, Austria
| | - Martin Imhof
- Karl Landsteiner Institute for cell-based therapy in Gynecology, Wiener Ring 3-5, 2100 Korneuburg, Austria
| | - Peter Chedraui
- Institute of Biomedicine, Research Area for Women's Health, Facultad de Ciencias Médicas, Universidad Católica de Santiago de Guayaquil, Av. Carlos J. Arosemena Km 1.5, Guayaquil, Ecuador
| | - Alois Jungbauer
- Christian-Doppler-Laboratory of Receptor Biotechnology, Muthgasse 18, 1190 Vienna, Austria; Department of Biotechnology, University of Natural Resources and Applied Life Sciences Vienna, Muthgasse 18, 1190 Vienna, Austria
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Kim JY, Lee MY, Park HM. The Effect of Eqoul, a Metabolite of Isoflavone, on Endothelial Cell-independent Vasodilatation of Human Uterine Artery In Vitro. J Bone Metab 2015; 22:57-69. [PMID: 26082915 PMCID: PMC4466446 DOI: 10.11005/jbm.2015.22.2.57] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 05/17/2015] [Accepted: 05/18/2015] [Indexed: 11/15/2022] Open
Abstract
Background The purpose of this study is to investigate 1) whether equol has the direct modulation on vascular tone of endothelium-denuded human uterine artery, and 2) if present, whether this equol-induced modulation of vascular tone is mediated by intracellular calcium modulation through Ca2+ & K+ channels on vascular smooth muscle cell membrane. Methods The uterine arteries were obtained at the time of hysterectomy from 15 women. The uterine smooth muscles were pretreated with phenylephrine, 10-5 M & high KCl solution 70 mM. The equol at 6 different concentrations from 10-11 to 10-6 M were used for the evaluation of modulatory action of equol on precontracted vascular smooth. The cumulative concentration-response for equol were determined on phenylephrine-induced contractions and compared with the results without pretreatment. Results Equol 10-11 to 10-6 M in concentration showed relaxation effect on vascular smooth muscle contraction which was induced by phenylephrine 10-5 M. This relaxation effect of equol was dose-dependent. Equol in same concentrations showed no significant effects on vascular smooth muscle contraction induced by high KCI solution. Phenylephrine-induced contraction was markedly reduced from 10-7 to 10-4 M in concentration by pretreatment of equol, but high KCI-induced contraction was not affected by pretreatment of equol. Conclusions This vasodilatation effect of equol may be induced by calcium antagonistic action, which was mediated through antagonistic action for receptor-dependent Ca2+ channel, but not for voltage-dependent Ca2+ channel. As far as we know, this is the first report of phytoestrogen equol on vascular reactivity of human vessels.
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Affiliation(s)
- Jeong Yuen Kim
- Department of Obstetrics and Gynecology, Chung-Ang University College of Medicine, Seoul, Korea
| | - Moo Yeol Lee
- Department of Physiology, Chung-Ang University College of Medicine, Seoul, Korea
| | - Hyoung Moo Park
- Department of Obstetrics and Gynecology, Chung-Ang University College of Medicine, Seoul, Korea
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Loutchanwoot P, Srivilai P, Jarry H. The influence of equol on the hypothalamic-pituitary-thyroid axis and hepatic lipid metabolic parameters in adult male rats. Life Sci 2015; 128:1-7. [PMID: 25744395 DOI: 10.1016/j.lfs.2015.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 11/15/2014] [Accepted: 02/02/2015] [Indexed: 12/14/2022]
Abstract
AIMS Equol, the principal active metabolite of soy-derived phytoestrogen daidzein, has well-known estrogenic actions. Results of several studies indicate that equol may also have anti-androgenic activities. However, mechanisms of action of equol on hypothalamic-pituitary-thyroid axis (HPTA) and hepatic lipid metabolism in adult male rats have not been determined yet. MAIN METHODS Equol at two doses of 100 and 250mg/kgbodyweight(BW)/day was orally gavaged for 5days to groups of 4-month-old male rats. As a positive anti-androgenic control group, animals received 100mg of pure anti-androgenic drug flutamide/kgBW/day. Circulating concentrations of thyroid hormones and lipids, and expression levels of genes underlying HPTA function were determined by radioimmunoassay and TaqMan® real-time reverse transcription polymerase chain reaction, respectively. KEY FINDINGS Flutamide significantly decreased relative prostate weight, whereas equol did not. Both equol and flutamide caused a significant increase in relative liver weights, and decreases in plasma levels of total tetraiodothyronine (T4) and triiodothyronine (T3), whereas free T4 and T3 concentrations were not reduced. Equol caused the marked down-regulation of hypothalamic thyrotropin-releasing hormone mRNA expression, whereas flutamide did not. Equol as well as flutamide significantly down-regulated the expression levels of pituitary thyrotropin beta-subunit mRNA, without altering thyrotropin secretion. Equol caused reductions in plasma levels of total cholesterol, high- and low-density lipoproteins and triglycerides, whereas flutamide exerted opposite effects. SIGNIFICANCE This is the first study to reveal that in male rats equol did not affect HPTA function and liver lipid metabolism through the anti-androgenic pathway, however, the intrinsic estrogenic actions of equol were observed.
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Affiliation(s)
- Panida Loutchanwoot
- Department of Biology Faculty of Science, Mahasarakham University, Khamriang Sub-district, Kantharawichai District, Mahasarakham Province 44150 Thailand.
| | - Prayook Srivilai
- Department of Biology Faculty of Science, Mahasarakham University, Khamriang Sub-district, Kantharawichai District, Mahasarakham Province 44150 Thailand
| | - Hubertus Jarry
- Department of Endocrinology, University Medical Center Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany
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Acharjee S, Zhou JR, Elajami TK, Welty FK. Effect of soy nuts and equol status on blood pressure, lipids and inflammation in postmenopausal women stratified by metabolic syndrome status. Metabolism 2015; 64:236-43. [PMID: 25441251 PMCID: PMC6800063 DOI: 10.1016/j.metabol.2014.09.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Revised: 08/19/2014] [Accepted: 09/19/2014] [Indexed: 01/14/2023]
Abstract
OBJECTIVE Soy has been associated with lower risk of cardiovascular disease in Asian countries which consume daily soy. Our study examined whether production of equol, an estrogen metabolite, affected the ability of soy nuts to improve cardiovascular risk factors. MATERIALS/METHODS Sixty postmenopausal women participated in a randomized, controlled, crossover trial of a Therapeutic Lifestyle Changes (TLC) diet alone and a TLC diet in which 0.5 cup of soy nuts (25 g of soy protein and 101 mg of aglycone isoflavones) replaced 25 g of nonsoy protein daily. Each diet was followed for 8 weeks at the end of which blood pressure (BP), lipid levels, adhesion molecules and inflammatory markers were measured. RESULTS Women with MetS had significantly higher baseline body mass index (BMI), BP, triglycerides (TG), and soluble intercellular adhesion molecule (sICAM) than women without MetS. In women with MetS on the soy diet, significant reductions in diastolic BP (7.7%; P=0.02), TG (22.9%; P=0.02), C-reactive protein (CRP) (21.4%; P=0.01) and sICAM (7.3%; P=0.03) were noted among equol producers compared to levels on the TLC diet. No significant changes were noted in equol nonproducers. Similarly, in women without MetS, only equol producers had significant reductions in diastolic BP (3.3%, P=0.02) and CRP (30%, P=0.04). In contrast to women with MetS, TG and sICAM levels were not affected in women without MetS, a finding possibly related to lower baseline levels. CONCLUSIONS Cardiovascular risk reduction with soy nuts is not uniform and may be greater among producers of equol.
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Affiliation(s)
- Subroto Acharjee
- Division of Cardiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA
| | - Jin-Rong Zhou
- Nutrition/Metabolism Laboratory, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA
| | - Tarec K Elajami
- Division of Cardiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA
| | - Francine K Welty
- Division of Cardiology, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA.
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Franke AA, Lai JF, Halm BM. Absorption, distribution, metabolism, and excretion of isoflavonoids after soy intake. Arch Biochem Biophys 2014; 559:24-8. [PMID: 24946051 PMCID: PMC4439254 DOI: 10.1016/j.abb.2014.06.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 05/19/2014] [Accepted: 06/06/2014] [Indexed: 01/29/2023]
Abstract
Soy is the major source of dietary exposure to isoflavonoids (IFLs). Accumulating evidence supports a role for soy and IFLs in the protection against many chronic diseases including cancer. After soy intake we found a biphasic IFL appearance pattern in plasma as well as in urine that we suggest to be due to IFL absorption in the small intestine (ca. 10%) during the first 2h after intake and IFL absorption in the large intestine (ca. 90%) 4-6 h after intake. While each IFL disappears from the circulation at different times excellent correlations between urinary and circulating IFL values were discovered and algorithms to convert urinary excretion values into circulating levels were established. We suggest the term 'apparent bioavailability' when using urinary data to describe IFL exposure. The IFL bioavailability was found to be influenced by gut bacteria, oral antibiotic treatment (OABX), and an individual's age and health status. While daidzein (DE) and genistein start to be absorbed minutes after intake, equol (EQ) appears in plasma only after a minimum of 8h following soy intake owing to the required transit time of DE to the colon where the conversion of DE to EQ takes place by intestinal microbiota. We have also shown that the apparent IFL bioavailability is higher in children than adults, higher in healthy versus non-healthy individuals, and decreased in children but increased in adults during OABX. Finally, we propose to use a urinary EQ/DE ratio of 0.018 with a DE threshold to identify EQ producers. With this cutoff definition we observed that EQ production is inconsistent over time in 5-30% of both premenopausal and postmenopausal women.
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Affiliation(s)
- Adrian A Franke
- University of Hawai'i Cancer Center, Honolulu, HI, United States.
| | - Jennifer F Lai
- University of Hawai'i Cancer Center, Honolulu, HI, United States
| | - Brunhild M Halm
- University of Hawai'i Cancer Center, Honolulu, HI, United States
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Kim EY, Shin JY, Park YJ, Kim AK. Equol induces mitochondria-mediated apoptosis of human cervical cancer cells. Anticancer Res 2014; 34:4985-4992. [PMID: 25202081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND/AIM The present study aimed to investigate anticancer properties of equol and demonstrate its underlying mechanisms of action in human cervical cancer HeLa cells. MATERIALS AND METHODS Inhibition of cell viability was examined by 3-(4,5-dimethylthiazoly-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was evaluated by observation of apoptotic cell morphology, and an increase of annexin-V(+) cells. Western blotting was used to examine apoptosis-related proteins. Flow cytometry was used to measure mitochondrial membrane potential (MMP) and reactive oxygen species (ROS). RESULTS Equol treatment inhibited HeLa cell proliferation in dose- and time-dependent manner. Equol-induced apoptotic cell death was accompanied by the activation of caspases, and alteration of MMP and mitochondrial membrane proteins; equol also rapidly triggered ROS production. Pre-treatment with N-acetylcysteine blocked loss of MMP, caused increase of Bcl-2-associated X protein (Bax)/B-cell lymphoma 2 (Bcl-2) ratio, caspase-8 activation, and apoptosis induced by equol. CONCLUSION Equol is a potential anticancer agent against HeLa, with possible mechanisms involved in ROS generation and mitochondrial membrane alteration.
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Affiliation(s)
- Eun Young Kim
- College of Pharmacy, Sookmyung Women's University, Seoul, Republic of Korea
| | - Jin Young Shin
- College of Pharmacy, Sookmyung Women's University, Seoul, Republic of Korea
| | - Young-Ja Park
- College of Pharmacy, Sookmyung Women's University, Seoul, Republic of Korea
| | - An Keun Kim
- College of Pharmacy, Sookmyung Women's University, Seoul, Republic of Korea
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Brown NM, Galandi SL, Summer SS, Zhao X, Heubi JE, King EC, Setchell KDR. S-(-) equol production is developmentally regulated and related to early diet composition. Nutr Res 2014; 34:401-9. [PMID: 24916553 DOI: 10.1016/j.nutres.2014.03.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 03/26/2014] [Accepted: 03/31/2014] [Indexed: 10/25/2022]
Abstract
S-(-)7-hydroxy-3-(4'-hydroxyphenyl)-chroman, or S-(-)equol, a biologically active intestinally derived bacterial metabolite of the soy isoflavones daidzin/daidzein, is not produced in neonatal life. Because its synthesis is dependent on equol-producing bacteria, we hypothesized that early nutrition may influence equol production. This prospective 2.5-year study determined the frequency of S-(-)equol production in healthy infants (n = 90) fed breast milk, soy infant formula, or cow's milk formula in their first year. Urinary S-(-)equol and daidzein were quantified by mass spectrometry after a standardized 3.5-day soy isoflavone challenge. Infants were tested at 6, 9, 12, 18, 24, and 36 months of age, and 3-day diet records were obtained at each visit to explore the effect of early and postweaning (>12 months) macronutrient and micronutrient dietary composition and S-(-)equol production. Use of antibiotics was also recorded. At age 6 months, none of the breast-fed infants produced S-(-)equol, whereas 3.8% and 6.0%, respectively, of soy and cow's milk formula-fed infants were equol producers. By age 3 years, 50% of the formula-fed infants were equol producers, compared with 25% of breast-fed infants. Use of antibiotics was prevalent among infants and may have impacted the stability of S-(-)equol production. No significant differences among the groups were observed in postweaning dietary intakes of total energy, carbohydrate, fiber, protein, fat, saturated fatty acids, or polyunsaturated fatty acids and the propensity to make S-(-)equol. In conclusion, S-(-)equol production is developmentally regulated and initially related to diet composition with the proportion of equol producers increasing over the first 3 years of life, with a trend for formula feeding favoring S-(-)equol production.
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Affiliation(s)
- Nadine M Brown
- Division of Clinical Mass Spectrometry, Department of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Stephanie L Galandi
- Division of Clinical Mass Spectrometry, Department of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Suzanne S Summer
- Center for Clinical and Translational Science and Training, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Xueheng Zhao
- Division of Clinical Mass Spectrometry, Department of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - James E Heubi
- Center for Clinical and Translational Science and Training, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Gastroenterology, Hepatology and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Eileen C King
- Department of Biostatistics & Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Kenneth D R Setchell
- Division of Clinical Mass Spectrometry, Department of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH.
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Eyster K, Appt S, Chalpe A, Register T, Clarkson T. Effects of equol on gene expression in female cynomolgus monkey iliac arteries. Nutr Metab Cardiovasc Dis 2014; 24:423-427. [PMID: 24525253 PMCID: PMC3972297 DOI: 10.1016/j.numecd.2013.09.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 08/19/2013] [Accepted: 09/05/2013] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND AIMS To examine effects of equol, the soy phytoestrogen metabolite, on gene expression in the monkey iliac artery. METHODS AND RESULTS A high fat/high cholesterol diet was fed to eight ovariectomized cynomolgus monkeys for 6.5 years. After biopsy of the left iliac artery, the animals were randomized to two treatment groups for 8 months; the treatment groups were equol (23.7 mg/100 g diet, n = 4) and vehicle (n = 4). The right iliac artery was removed at necropsy. Gene expression in the iliac arteries in response to equol was determined by DNA microarray. Comparison of atherosclerotic lesions and plasma lipids at pre-versus post-equol treatment time points and in vehicle versus equol treatment groups did not identify any significant differences. Despite the lack of effect of equol on these parameters, 59 genes were down-regulated and 279 were up-regulated in response to equol. Comparison of these data to previous work identified 10 genes regulated in opposite directions by equol compared to presence of atherosclerosis plaque (Menopause 2011; 18:1087-1095) and 55 genes differentially expressed in the same direction in response to both equol and estradiol (Eyster et al., Menopause 2014;21:143-152.). CONCLUSIONS Similar responses of genes to both equol and estradiol may reflect the extent to which equol serves as a natural selective estrogen receptor modulator in the arteries. Opposite responses of 10 genes to equol versus the presence of atherosclerosis implicates those genes in the potential protective effects of equol in arteries.
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Affiliation(s)
- K Eyster
- Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, 414 E. Clark St., Vermillion, SD 57069, USA.
| | - S Appt
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - A Chalpe
- Division of Basic Biomedical Sciences, Sanford School of Medicine of the University of South Dakota, 414 E. Clark St., Vermillion, SD 57069, USA
| | - T Register
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - T Clarkson
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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Neese SL, Pisani SL, Doerge DR, Helferich WG, Sepehr E, Chittiboyina AG, Rotte SCK, Smillie TJ, Khan IA, Korol DL, Schantz SL. The effects of dietary treatment with S- equol on learning and memory processes in middle-aged ovariectomized rats. Neurotoxicol Teratol 2014; 41:80-8. [PMID: 24368316 PMCID: PMC3943933 DOI: 10.1016/j.ntt.2013.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Revised: 11/22/2013] [Accepted: 12/17/2013] [Indexed: 01/18/2023]
Abstract
The use of over-the-counter botanical estrogens containing isolated soy isoflavones, including genistein and daidzein, has become a popular alternative to traditional hormone therapies. Menopausal women use these products as an aide in healthy aging, including for the maintenance of cognitive function. The safety and efficacy of many of these commercial preparations remain unknown. Previous research in our lab found that treatment of ovariectomized (OVX) female Long-Evans rats with genistein impaired working memory in an operant delayed spatial alternation (DSA) task and response learning in a plus-maze, but enhanced place learning assessed in the plus-maze. The present study further examined the effects of isolated isoflavones on working memory and place learning by treating middle-aged (12-13 month old) OVX female Long-Evans rats with S-equol, the exclusive enantiomer produced by metabolism of daidzein in the mammalian gut. S-equol binds selectively to ERβ with an affinity similar to that of genistein but has low transcriptional potency. For DSA testing, S-equol at 1.94, 0.97 mg, or 0mg (sucrose control) was orally administered to animals daily, 30 min before behavioral testing, and again both 4 and 8 hours after the first treatment. Rats were tested on the DSA task following the first, morning dose. For place learning, rats received 0.97 mg S-equol every 4 hours during the light portion of the cycle beginning 48 hours prior to behavioral testing (total exposure 8.7 mg S-equol). S-equol treatment was largely without effect on the DSA and place learning tasks. This is the first study to test the behavioral effects of isolated S-equol in OVX rodents, and shows that, unlike genistein or estradiol, repeated daily treatment with this isoflavone metabolite does not alter learning and memory processes in middle-aged OVX rats.
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Affiliation(s)
- Steven L Neese
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001S. Lincoln Avenue, Urbana, IL 61802, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, 505 South Goodwin Avenue, Urbana, IL 61801, USA; Department of Psychology and Neuroscience, Baldwin Wallace University, 275 Eastland Road, Berea, OH 44017, USA.
| | - Samantha L Pisani
- Neuroscience Program, University of Illinois at Urbana-Champaign, 505 South Goodwin Avenue, Urbana, IL 61801, USA.
| | - Daniel R Doerge
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079-9502, USA.
| | - William G Helferich
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 905S Goodwin Avenue, Urbana, IL 61801, USA.
| | - Estatira Sepehr
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079-9502, USA.
| | - Amar G Chittiboyina
- National Center for Natural Product Research, University of Mississippi, 3011 Thad Cochran Research Center, University, MS 38677, USA.
| | - Sateesh Chandra Kumar Rotte
- National Center for Natural Product Research, University of Mississippi, 3011 Thad Cochran Research Center, University, MS 38677, USA.
| | - Troy J Smillie
- National Center for Natural Product Research, University of Mississippi, 3011 Thad Cochran Research Center, University, MS 38677, USA.
| | - Ikhlas A Khan
- National Center for Natural Product Research, University of Mississippi, 3011 Thad Cochran Research Center, University, MS 38677, USA.
| | - Donna L Korol
- Neuroscience Program, University of Illinois at Urbana-Champaign, 505 South Goodwin Avenue, Urbana, IL 61801, USA; Department of Biology, Syracuse University, 107 College Place, Syracuse, NY 13244, USA.
| | - Susan L Schantz
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, 2001S. Lincoln Avenue, Urbana, IL 61802, USA; Neuroscience Program, University of Illinois at Urbana-Champaign, 505 South Goodwin Avenue, Urbana, IL 61801, USA.
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Loutchanwoot P, Srivilai P, Jarry H. Lack of anti-androgenic effects of equol on reproductive neuroendocrine function in the adult male rat. Horm Behav 2014; 65:22-31. [PMID: 24211351 DOI: 10.1016/j.yhbeh.2013.10.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 10/29/2013] [Accepted: 10/31/2013] [Indexed: 10/26/2022]
Abstract
Equol (EQ), a metabolite of the soy isoflavone daidzein, has well known estrogenic properties. Data from animal studies suggested that EQ may act also as an anti-androgen. However, data regarding how EQ may affect brain functions like the regulation of neuroendocrine activity and reproductive outcomes in adult male rats are still lacking. We therefore investigated the effects of EQ on sex-steroid regulated gene expression in the brain [medial preoptic area/anterior hypothalamus (MPOA/AH) and medial basal hypothalamus/median eminence (MBH/ME)], pituitary, and prostate as a reference androgen-dependent organ. Furthermore reproductive outcomes were evaluated. The anti-androgen flutamide (FLUT) served as reference compound. Male rats (n=12 per group) were treated by gavage for 5 days with either EQ (100 or 250 mg/kgBW/day), or FLUT 100 mg/kgBW/day. All vehicle- and EQ-treated males showed successful reproductive outcomes, whereas FLUT-exposed males had severe reproductive impairments resulted in infertility. FLUT decreased relative weights of prostate, seminal vesicles and epididymides, and increased serum levels of luteinizing hormone, follicle-stimulating hormone, testosterone and 5α-dihydrotestosterone without altering prolactin levels, whereas EQ exerted opposite effects. Both EQ and FLUT decreased gonadotropin releasing hormone (GnRH) expression in the MPOA/AH. Only FLUT upregulated levels of GnRH receptor expression both in the MBH/ME and pituitary. While EQ downregulated the hypothalamic ERα and ERβ expressions, but FLUT did not. In the prostate, only FLUT upregulated both ERα and AR mRNA expression levels. Taken together, our findings are the first data that EQ did not induce anti-androgenic effects on brain, prostate and male reproductive parameters, however, estrogenic neuroendocrine and reproductive effects of EQ were observed.
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Affiliation(s)
- Panida Loutchanwoot
- Department of Biology, Faculty of Science, Mahasarakham University, Khamriang Sub-district, Kantarawichai District, Mahasarakham Province 44150, Thailand.
| | - Prayook Srivilai
- Department of Biology, Faculty of Science, Mahasarakham University, Khamriang Sub-district, Kantarawichai District, Mahasarakham Province 44150, Thailand.
| | - Hubertus Jarry
- Department of Endocrinology, University Medical Center Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.
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Zheng W, Hou Y, Su Y, Yao W. Lactulose promotes equol production and changes the microbial community during in vitro fermentation of daidzein by fecal inocula of sows. Anaerobe 2013; 25:47-52. [PMID: 24315807 DOI: 10.1016/j.anaerobe.2013.11.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Revised: 11/21/2013] [Accepted: 11/25/2013] [Indexed: 11/18/2022]
Abstract
Equol has higher biological effects than other isoflavones. However, only about 30-50% of humans possess a microbiota capable of producing equol from dietary daidzein. In recent years, interest has grown in dietary applications to improve equol production in human and other animals. In this study, lactulose was used as a potential equol-promoting prebiotic in vitro. The effect of lactulose on transformation of daidzein into equol by sows' fecal microbiota was investigated. Results showed that lactulose treatment improved bacteria growth parameters, changing the kinetics of fermentation in vitro. Lactulose significantly increased total gas production, T1/2, Tmax, and Rmax. Furthermore, lactulose altered the microflora composition, increased equol production associated with a reduction in the population of methanogen and increased the sulfate-reducing bacteria population during 24 h of incubation. Here, we report for the first time that in a certain condition (sealing or high pressure), via a dihydrodaidzein (DHD) pathway equol might be able to reform to daidzein by further metabolism using lactulose as a substrate. This study proposes that "hydrogen-producing prebiotic" might be a novel way to promote equol production in vivo or in vitro.
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MESH Headings
- Animals
- Bacteria, Anaerobic/classification
- Bacteria, Anaerobic/drug effects
- Bacteria, Anaerobic/growth & development
- Bacteria, Anaerobic/metabolism
- Biota
- Cluster Analysis
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Equol/metabolism
- Feces/microbiology
- Fermentation
- Gases/metabolism
- Isoflavones/metabolism
- Lactulose/metabolism
- Molecular Sequence Data
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Swine
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Affiliation(s)
- Weijiang Zheng
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
| | - Yanjun Hou
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
| | - Yong Su
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China.
| | - Wen Yao
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China; Key Lab of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing, Jiangsu 210095, China.
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Tousen Y, Uehara M, Kruger MC, Ishimi Y. Effects of dietary fibre and tea catechin, ingredients of the Japanese diet, on equol production and bone mineral density in isoflavone-treated ovariectomised mice. J Nutr Sci 2012; 1:e13. [PMID: 25191542 DOI: 10.1017/jns.2012.14] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 08/04/2012] [Accepted: 08/08/2012] [Indexed: 12/31/2022] Open
Abstract
Equol is a metabolite of the isoflavone daidzein (Dz) and is produced by the bacterial
microflora in the distal intestine and colon. Some epidemiological studies have reported
an association between increased equol production and intakes of green tea or dietary
fibre, which are ingredients of the standard Japanese diet. We examined the effects of a
diet supplemented with Dz and tea catechin or dietary fibre on equol production and bone
mineral density in ovariectomised (OVX) mice. Female mice of the ddY strain were either
sham operated or OVX. OVX mice were fed a control diet, a 0·1 % Dz-supplemented diet or a
0·1 % Dz diet supplemented with one of the food components commonly consumed in the
Japanese diet. The mice were given 1 % tea catechin (w/w) as part of the diet in Expt 1 or
5 % polydextrose (PD) and 5 % raffinose (Raf) (w/w) as part of the diet in Expt 2.
Catechin reduced serum equol levels and attenuated the beneficial effect of Dz on femoral
bone loss. The soluble dietary fibres PD and Raf stimulated equol production, and enhanced
the bone-protective effects of Dz on femoral bone. These results suggest that dietary
fibre, in particular, PD, may alter the bioavailability of isoflavones and prevent
osteopenia in OVX mice.
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Abstract
In this study, we demonstrate that equol has fungicidal activities against Candida albicans. The minimum inhibitory and minimum fungicidal concentrations of equol against C. albicans were 516 and 1,032 µM, respectively. Two separate viability assays found that equol changed the integrity of the C. albicans cell membrane, possibly by formation of membrane lesions. Scanning electron microscopy demonstrated ultrastructural changes.
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Affiliation(s)
- Jeong Ah Lee
- Department of Cell Biology, College of Medicine, Konyang University, Daejeon 302-718, Korea
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Cai L, Wang PY, Zhang YM. Advances in research on equol-producing bacteria. Shijie Huaren Xiaohua Zazhi 2010; 18:1360-1365. [DOI: 10.11569/wcjd.v18.i13.1360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The main components of isoflavones are genistein and daidzein, both of which have beneficial effects on many diseases. Numerous studies have demonstrated that the biological properties of isoflavones are partially attributed to equol. Daidzein can be transformed to equol exclusively by intestinal bacteria, and only 30%-50% of humans possess such type of bacteria. In this article, we will give an overview of recent advances in research on equol-producing bacteria harbored in the intestine of humans and animals. The bacteria capable of converting daidzein to equol directly will be highlighted. It is revealed that equol-producing bacteria can produce equol during in vitro anaerobic culture.
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Kwak HS, Park SY, Kim MG, Yim CH, Yoon HK, Han KO. Marked individual variation in isoflavone metabolism after a soy challenge can modulate the skeletal effect of isoflavones in premenopausal women. J Korean Med Sci 2009; 24:867-73. [PMID: 19794985 PMCID: PMC2752770 DOI: 10.3346/jkms.2009.24.5.867] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Accepted: 12/03/2008] [Indexed: 12/05/2022] Open
Abstract
Soy-isoflavones may act as estrogenic agonists or antagonists depending on the endogenous hormone status. These clinical effects can be exerted variably in individuals by the metabolic ability to produce a more potent metabolite than precursors. The objective of this randomized, double-blind, placebo-controlled study was to investigate the skeletal effect of isoflavones according to their metabolic variability in premenopausal women. Volunteers were randomly assigned to receive either soy-extract isoflavones (n=32) or lactose (n=21) once a day for three menstrual cycles. After intervention, the urinary excretions of isoflavones and their metabolites were significantly higher in the soy group than in the placebo group and showed a large inter-individual variation. Women in the soy group were divided into subgroups according to their ability to excrete more potent metabolites. Serum osteocalcin and urine deoxypyridinoline showed a tendency to increase after a challenge in equol high-excretors. Serum osteocalcin concentration in the genistein high-excretors increased significantly after a challenge (P=0.04) but did not increase in either the placebo or genistein low-excretors. An estrogenic antagonistic effect of isoflavones on bone turnover was observed in premenopausal women who are able to produce more potent metabolites.
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Affiliation(s)
- Ho Seok Kwak
- Division of Endocrinology, Department of Internal Medicine, Cheil General Hospital and Women's Healthcare Center, Kwandong University School of Medicine, Seoul, Korea
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