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Amato R, Gardin JF, Tooze JA, Cline JM. Organ Weights in Relation to Age and Sex in Cynomolgus Monkeys ( Macaca fascicularis). Toxicol Pathol 2022; 50:574-590. [PMID: 35383510 DOI: 10.1177/01926233221088283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Laboratory animal research is an important contributor to both human and animal medicine. Currently, there is extensive use of cynomolgus monkeys (Macaca fascicularis) in pathology and toxicology research. The purpose of this study was to define reference values for absolute and percentage organ weights in M fascicularis of different ages and sex. Organ weights were obtained from necropsies of 1022 cynomolgus monkeys at the Wake Forest School of Medicine from 1997 to 2018. Distributions of absolute and percentage weights for each organ were described; sex and age groups were compared using analysis of variance. Age effects on percentage of body weights for each organ were analyzed within each sex. Diet effects were also analyzed. This evaluation showed that male body weights and absolute organ weights were greater for all age groups; however, female organ to body weight percentages were greater for most organs. Percentage of organ weight to body weight declined for the adrenals, brain, lung, thyroid and thymus during maturation, whereas percentage weight of pancreas, prostate, testes, and uterus increased. Animals consuming a high-fat, Western-type diet had a lower body weight than animals consuming a carbohydrate-rich chow diet. This information will be useful for further toxicology and pathology studies concerning cynomolgus monkeys.
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Affiliation(s)
| | - Jean F Gardin
- Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Janet A Tooze
- Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - J Mark Cline
- Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
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2
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Walker RR, Patel JR, Gupta A, Davidson AM, Williams CC, Payton-Stewart F, Boué SM, Burow ME, Khupse R, Tilghman SL. Glyceollins Trigger Anti-Proliferative Effects in Hormone-Dependent Aromatase-Inhibitor-Resistant Breast Cancer Cells through the Induction of Apoptosis. Int J Mol Sci 2022; 23:2887. [PMID: 35270029 PMCID: PMC8911299 DOI: 10.3390/ijms23052887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/01/2022] [Accepted: 03/03/2022] [Indexed: 11/16/2022] Open
Abstract
Aromatase inhibitors (AIs) are standard treatment for estrogen-dependent postmenopausal breast tumors; however, resistance develops leading to tumor relapse and metastasis. We previously demonstrated that glyceollin inhibits proliferation, survival, and migration of hormone-independent letrozole-resistant breast cancer. Since many AI-resistant tumors remain hormone-dependent, identifying distinctions between estrogen-receptor-positive (ER+) and ER-negative (ER-) AI-resistant tumor response to therapy is critical. We hypothesize that treating ER+ letrozole-resistant T47D breast cancer cells (T47DaromLR) with a combination of 10 μM glyceollin and 0.5 μM lapatinib (a dual EGFR/HER2 inhibitor) will decrease cell proliferation through induction of apoptosis. The T47DaromLR cells were found to overexpress HER2 and MAPK while maintaining aromatase and ER levels compared to their letrozole-sensitive (T47Darom) counterparts. In the absence of estrogen stimulation, glyceollin ± lapatinib had no effect on the proliferation of the T47Darom cells, while glyceollin treatment caused 46% reduction in the proliferation of T47DaromLR cells, which was further diminished when combined with lapatinib. While neither agent influenced cell migration, glyceollin and lapatinib reduced S and G2/M phase cell entry and exclusively induced apoptosis by 1.29-fold in the T47DaromLR cells. Taken together, these results suggest that glyceollins and lapatinib may have potential as a novel combination therapeutic approach for hormone-dependent, letrozole-resistant tumors.
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Affiliation(s)
- Rashidra R. Walker
- Division of Basic Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, 1415 S. Martin L. King Jr. Blvd., Tallahassee, FL 32307, USA; (R.R.W.); (J.R.P.); (A.M.D.)
| | - Jankiben R. Patel
- Division of Basic Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, 1415 S. Martin L. King Jr. Blvd., Tallahassee, FL 32307, USA; (R.R.W.); (J.R.P.); (A.M.D.)
| | - Akash Gupta
- Department of Medicine, University of Arizona, 1500 N. Campbell Ave., Tucson, AZ 85724, USA;
| | - A. Michael Davidson
- Division of Basic Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, 1415 S. Martin L. King Jr. Blvd., Tallahassee, FL 32307, USA; (R.R.W.); (J.R.P.); (A.M.D.)
| | - Christopher C. Williams
- Division of Basic Sciences, College of Pharmacy, Xavier University of Louisiana, 1 Drexel Dr., New Orleans, LA 70125, USA;
| | - Florastina Payton-Stewart
- Division of Mathematics and Physical Sciences, College of Arts and Sciences, Xavier University of Louisiana, 1 Drexel Dr., New Orleans, LA 70125, USA;
| | - Stephen M. Boué
- Southern Regional Research Center, United States Department of Agriculture, Agricultural Research Service, 1100 Robert E. Lee Blvd., New Orleans, LA 70124, USA;
| | - Matthew E. Burow
- Section of Hematology and Medical Oncology, School of Medicine, Tulane University, New Orleans, LA 70112, USA;
| | - Rahul Khupse
- College of Pharmacy, The University of Findlay, 1000 N. Main St., Findlay, OH 45840, USA;
| | - Syreeta L. Tilghman
- Division of Basic Sciences, College of Pharmacy and Pharmaceutical Sciences, Florida A&M University, 1415 S. Martin L. King Jr. Blvd., Tallahassee, FL 32307, USA; (R.R.W.); (J.R.P.); (A.M.D.)
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Risk assessment for peri- and post-menopausal women taking food supplements containing isolated isoflavones. EFSA J 2015. [DOI: 10.2903/j.efsa.2015.4246] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Song Y, Santen RJ, Wang JP, Yue W. Inhibitory effects of a bazedoxifene/conjugated equine estrogen combination on human breast cancer cells in vitro. Endocrinology 2013; 154:656-65. [PMID: 23254198 DOI: 10.1210/en.2012-2038] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Breast cancer incidence is increased in women receiving menopausal hormone therapy with estrogen plus progestin but not with estrogen alone. The use of a tissue-selective estrogen complex (TSEC) has been proposed as a novel menopausal hormone therapy strategy to eliminate the requirement for a progestogen. Combination of bazedoxifene (BZA) with conjugated estrogens (CEs), the first TSEC, has shown beneficial effects. Whether it would exert antiestrogenic effects on breast cancer is not clear. To address this issue, we compared estradiol (E(2)) and CE alone on proliferation and apoptosis in MCF-7 breast cancer cells. CE stimulated growth of MCF-7 cells at a peak concentration 10-fold higher than required for E(2). Both CE and E(2) alone increased DNA synthesis and reduced apoptosis with activation of MAPK, Akt, and p70S6K and up-regulation of antiapoptotic factors survivin, Bcl-2, and X-linked inhibitor of apoptosis protein, These effects could be completely blocked by BZA. Gene expression studies demonstrated that CE and E(2) were equally potent on expression of cMyc, pS2, and WNT1 inducible signaling pathway protein 2, whereas the stimulatory effects of CE on progesterone receptor and amphiregulin expression were weaker than E(2). BZA effectively blocked each of these effects and showed no estrogen agonistic effects when used alone. Our results indicate that the stimulatory effects of E(2) or CE on breast cancer cells could be completely abrogated by BZA. These studies imply that the CE/BZA, TSEC, exerts antiestrogenic effects on breast cancer cells and might block the growth of occult breast neoplasms in postmenopausal women, resulting in an overall reduction in tumor incidence.
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Affiliation(s)
- Yan Song
- Division of Endocrinology, Department of Medicine, University of Virginia Health System, Charlottesville, VA 22908, USA
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Hill GD, Moore AB, Kissling GE, Flagler ND, Ney E, Cline JM, Dixon D. Effects of hormonally active agents on steroid hormone receptor expression and cell proliferation in the myometrium of ovariectomized macaques. Toxicol Pathol 2011; 39:508-15. [PMID: 21411722 DOI: 10.1177/0192623311401045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hormone replacement therapy and selective estrogen receptor modulators have been controversial treatment options for postmenopausal women because of their potential health benefits and/or risks. In this study, we determine the effects of the hormonally active compounds, conjugated equine estrogens (CEE), medroxyprogesterone acetate (MPA), CEE + MPA, and tamoxifen (TAM) on the myometrium of ovariectomized macaques. Immunoexpression of estrogen receptor-α (ERα), progesterone receptor (PR), and Ki-67 in the myometrium is assessed. We found no significant difference in ERα myometrial expression in the CEE, MPA, and CEE + MPA treatment groups, but there was a significant decrease in expression in animals administered TAM versus controls. Conjugated equine estrogen-, TAM-, and CEE + MPA-treated animals had significantly increased expression of PR in myometrial cells and there was no difference in PR expression in cells from MPA-treated animals versus control animals. Myometrial cell proliferation did not significantly differ between the controls and any of the treatment groups, although normalized Ki-67 values were somewhat higher in the CEE and TAM groups. These data suggest that ERα and PR expression in the myometrium is influenced by treatment with hormonally active agents.
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Affiliation(s)
- Georgette D Hill
- Integrated Laboratory Systems (ILS), Research Triangle Park, North Carolina, USA
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Wood CE, Kaplan JR, Fontenot MB, Williams JK, Cline JM. Endometrial profile of tamoxifen and low-dose estradiol combination therapy. Clin Cancer Res 2010; 16:946-56. [PMID: 20103679 DOI: 10.1158/1078-0432.ccr-09-1541] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Combination estrogen + progestin therapy has been associated with increased breast cancer risk in postmenopausal women. Selective estrogen receptor modulators (SERM) are potential alternatives to progestins, although the endometrial safety of estrogen + SERM co-therapies is not known. The goal of this study was to evaluate the endometrial profile of low-dose estradiol and the SERM tamoxifen alone and in combination. EXPERIMENTAL DESIGN Twenty-four postmenopausal female cynomolgus macaques were randomized by social group to receive placebo, low-dose micronized estradiol (E(2); 0.25 mg/1,800 kcal), the SERM tamoxifen (Tam; 20 mg/1,800 kcal), or E(2) + Tam for 4 months in a parallel-arm design. RESULTS Tamoxifen alone resulted in overlapping but distinct effects compared with E(2). Both E(2) and Tam increased uterine weight and endometrial thickness, whereas only E(2) increased endometrial proliferation. Morphologic effects were similar for Tam and E(2) + Tam, which both induced stromal fibrosis and cystic change. Tamoxifen inhibited E(2)-induced proliferation and expression of genes related to cell cycle progression while exhibiting mixed agonist and antagonist effects on gene markers of estrogen receptor activity. The gene expression profile for E(2) + Tam was distinct from either E(2) or Tam alone but dominated by the Tam effect for estrogen-regulated genes. Tam also attenuated E(2) effects on both vaginal maturation and cervical epithelial height. CONCLUSIONS These findings characterize a novel phenotype resulting from estrogen + SERM co-therapy. The predominance of Tam effects on endometrial proliferation, morphology, and transcriptional profiles suggests that endometrial risks for E(2) + Tam may be similar to Tam alone.
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Affiliation(s)
- Charles E Wood
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, NC, USA
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Taylor CK, Levy RM, Elliott JC, Burnett BP. The effect of genistein aglycone on cancer and cancer risk: a review of in vitro, preclinical, and clinical studies. Nutr Rev 2009; 67:398-415. [PMID: 19566600 DOI: 10.1111/j.1753-4887.2009.00213.x] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In Asian epidemiological studies, health benefits, including reduced incidence of breast and prostate cancers, are attributed to soy food and isoflavone consumption. The recent increased intake of soy foods and supplements in the American diet has raised concerns about the possible estrogen-like effects of natural isoflavones and possible promotion or propagation of estrogen-sensitive cancers. These concerns are primarily based on in vitro and rodent data which suggest that genistein aglycone can stimulate tumor cell proliferation and growth in mice having deficient immune systems. In contrast, a recent nested case-control study and meta-analysis of numerous epidemiological studies show an inverse correlation between genistein intake and breast cancer risk. Furthermore, clinical studies in osteopenic and osteoporotic, postmenopausal women support the breast and uterine safety of purified naturally derived genistein administered for up to 3 years. In this review, we summarize the in vitro, preclinical and clinical evidence for the safety of natural genistein.
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Cline JM, Wood CE. Estrogen/isoflavone interactions in cynomolgus macaques (Macaca fascicularis). Am J Primatol 2009; 71:722-31. [PMID: 19322873 DOI: 10.1002/ajp.20680] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Soy isoflavones are phytoestrogenic components of dietary soy, which are widely consumed for their potential health benefits. Soy isoflavones appear to decrease breast and endometrial cancer risk in human observational studies, but paradoxically stimulate growth of breast cancer cells in culture and uterine enlargement in rodents. We have shown that these compounds are not estrogenic in cynomolgus monkeys even at relatively high doses, but that they reduce estrogen-induced proliferative responses of the breast and endometrium. This effect may be mediated through estrogen receptor interactions and/or modulation of endogenous estrogen metabolism. Interindividual variation in isoflavone absorption and metabolism contributes to the degree of estrogen antagonistic effect. Our recent studies have also shown that individual isoflavone metabolites such as glyceollins may have unique selective estrogen receptor modulator-like activity, acting as tissue-specific antagonists without agonist activity. Rodent studies and human epidemiologic data suggest that timing of exposure and dose relative to endogenous estrogen concentrations are important determinants of effect, and studies of dietary soy on breast development and pubertal maturation are under way. Because soy isoflavones are both abundant in standard monkey chow diets and widely available as dietary supplements for human beings, these findings have broad relevance to the health of human and nonhuman primates.
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Affiliation(s)
- J Mark Cline
- Wake Forest University Primate Center, Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1040, USA.
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Wood CE, Lees CJ, Cline JM. Mammary gland and endometrial effects of testosterone in combination with oral estradiol and progesterone. Menopause 2009; 16:466-76. [PMID: 19265727 PMCID: PMC2755604 DOI: 10.1097/gme.0b013e318191747a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The goal of this pilot study was to evaluate the effects of testosterone (T) cotherapy on mammary gland and endometrial measures in a postmenopausal primate model. METHODS Twenty-five surgically postmenopausal cynomolgus monkeys were randomized by social group to receive daily treatment with (1) placebo, (2) oral micronized 17beta-estradiol (1 mg/d equivalent in women) + progesterone (200 mg/d equivalent in women) (E + P), or (3) E + P with T administered via subcutaneous pellets for 8 weeks at a high dose (15 mg) followed by 8 weeks at a low dose (1.5 mg) (E + P + T). The main outcome measures were breast and endometrial epithelial proliferation, as measured by Ki67/MIB1 immunolabeling. RESULTS Intralobular breast proliferation did not differ significantly among groups after 8 weeks of treatment but was marginally higher (P = 0.03) in the E + P + T group after 16 weeks of treatment. No significant increase in proliferation was seen for E + P alone. Comparable changes in mammary gland markers of estrogen-receptor activity were seen for the E + P and E + P + T groups. In the endometrium, the addition of T did not increase endometrial glandular proliferation or estrogen-receptor activity or result in any distinct histologic changes. CONCLUSIONS The findings of this study do not support the idea that T antagonizes the effects of combined hormone therapy on breast proliferation or markers of estrogen-receptor activity. Overall, the short-term effects of T cotherapy on the mammary gland and endometrium were minimal.
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Affiliation(s)
- Charles E Wood
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, NC 27157-1040, USA.
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Scott LM, Xu X, Veenstra TD, Tooze JA, Wood CE, Register TC, Kock ND, Cline JM. Past oral contraceptive use and current dietary soy isoflavones influence estrogen metabolism in postmenopausal monkeys (Macaca fascicularis). Cancer Epidemiol Biomarkers Prev 2008; 17:2594-602. [PMID: 18843000 DOI: 10.1158/1055-9965.epi-08-0278] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Estrogen metabolism may play an important role in mammary carcinogenesis in postmenopausal women. We evaluated the effects of prior oral contraceptive (OC) treatment and current soy isoflavone consumption on endogenous estrogen metabolite concentration and biomarkers of tissue estrogen exposure in a monkey model. One hundred eighty-one female cynomolgus macaques were randomized to receive OC or placebo for 26 months premenopausally, then ovariectomized and randomized to one of three diets for 36 months: an isoflavone-depleted soy protein isolate (Soy-) diet, a diet containing soy protein isolate with a human equivalent of 129 mg isoflavone/d (Soy+), or a Soy- diet supplemented with conjugated equine estrogens (CEE+) at a human equivalent dose of 0.625 mg/d. Reverse-phase high-performance liquid chromatography directly coupled with tandem mass spectrometry was used to measure the concentrations of estrogen species in urine samples. Generally, prior OC treatment was associated with significantly reduced urinary estrogen metabolites (25-55% reduction; P<0.05 for each versus OC-). Animals that consumed isoflavones postmenopausally had increased urinary 2-hydroxyestrone and 16alpha-hydroxyestrone (50% and 56% increases, respectively), but reduced levels of 2-hydroxyestradiol, 2-methoxyestradiol, and 17-epiestriol (92%, 63%, and 66%, respectively), compared with animals fed a Soy- diet. Isoflavones did not have widespread effects on uterine or mammary proliferation biomarkers, whereas prior OC significantly reduced two of three proliferation end points in the endometrium. Premenopausal OCs may have long-term systemic effects on response to estrogen and its metabolism whereas postmenopausal dietary isoflavones may alter endogenous estrogen metabolism in a modest but selective manner.
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Affiliation(s)
- Latanya M Scott
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
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Scott LM, Durant P, Leone-Kabler S, Wood CE, Register TC, Townsend A, Cline JM. Effects of prior oral contraceptive use and soy isoflavonoids on estrogen-metabolizing cytochrome P450 enzymes. J Steroid Biochem Mol Biol 2008; 112:179-85. [PMID: 18955142 PMCID: PMC2646417 DOI: 10.1016/j.jsbmb.2008.10.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 09/26/2008] [Accepted: 10/02/2008] [Indexed: 11/19/2022]
Abstract
Estrogen exposure and metabolism may play an important role in the development of estrogen-sensitive cancers in postmenopausal women. In this study we investigated whether past oral contraceptive (OC) administration or current dietary isoflavonoids (IF) affected expression and/or activity of steroid hormone-metabolizing cytochrome P450 (CYP) enzymes using complementary primate and cell culture models. One-hundred-eighty-one female cynomolgus macaques were randomized to receive OC or nothing for 26 months premenopausally, then ovariectomized and randomized to one of three diets for 36 months: an IF-depleted soy protein isolate (Soy-) diet, a Soy diet with IF (Soy+), or a Soy- diet supplemented with conjugated equine estrogens (CEE). Prior OC-treatment significantly reduced CYP gene expression in the mammary gland (< or =60% of OC-). Dietary IFs had no effect on CYP expression, while CEE-treatment decreased CYP1A1 and increased CYP3A4 mRNA in a tissue-specific manner. For in vitro studies, we measured effects of the isoflavonoids genistein, daidzein and equol on CYP activity using intact V79 cells stably transfected to express CYP1A1, CYP1B1, or CYP3A4. All three IFs significantly altered CYP activity in a dose-dependent and isoform-specific manner (20-95% inhibition versus controls). These results suggest potential mechanisms for prior OC and dietary IF effects on cancer risk in estrogen-responsive tissues.
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Affiliation(s)
- L M Scott
- Department of Pathology, Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
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Abstract
This review describes the normal biology and physiology of the mammary gland in macaques, including the typical histologic appearance across the life span (development, reproductive maturity, lactation, and senescence). The molecular events regulating breast morphogenesis are described, as well as systemic and local hormonal regulators of mammary gland proliferation, differentiation, and function. Similarities and differences to the human breast are described. Regulatory events are illuminated by discussion of genetically modified mouse models. Tissue response markers, including immunohistochemical markers of proliferation and other hormonally induced changes and studies to date, regarding the effects of exogenous hormones, are briefly summarized. In general, estrogens stimulate progesterone receptor expression and proliferation in the mammary gland, and combinations of estrogens and progestogens cause greater proliferation than estrogens alone. Evaluation of novel chemical agents in macaques requires careful evaluation of age and hormonal context to avoid the confounding effects of mammary gland development, past reproductive history, and other influences on mammary gland morphology. The expression of proliferation markers and progesterone receptors may be used as biomarkers to measure chemically induced hormonal effects.
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Affiliation(s)
- J Mark Cline
- Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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Ethanol extract of Psoralea corylifolia L. and its main constituent, bakuchiol, reduce bone loss in ovariectomised Sprague–Dawley rats. Br J Nutr 2008; 101:1031-9. [DOI: 10.1017/s0007114508066750] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of the present study was to investigate whether ethanol extracts of Psoralea corylifolia L. (PCE) and its active component protect against bone loss in ovariectomised rats. We screened oestrogenic activities of the main extract fractions using in vitro assays and identified bakuchiol as the most active oestrogenic component by HPLC and LC/MS, and then demonstrated that bakuchiol had strong binding affinity for oestrogen receptor (ER) α. Seventy female Sprague–Dawley rats were assigned to either a sham-operated group (n 10) or an ovariectomised group (n 60). The ovariectomised group was subdivided into six groups, each containing ten rats: vehicle group, two bakuchiol-treated groups (dose of 15 mg/kg per d or 30 mg/kg per d; ten rats for each group), two PCE-supplemented groups (0·25 % or 0·5 % extracts of diets; ten rats for each group) and a 17β-oestradiol (E2)-treated group (20 μg/kg per d). We recorded weight and feed intake every week, and killed all animals after 6 weeks. Blood was collected, and the uterus, kidneys and livers were removed. Bakuchiol has a three-fold higher binding affinity for ERα than for ERβ. Bakuchiol and PCE treatments had no uterotrophic activity even though they demonstrated oestrogenic activity in the in vitro assays. Bakuchiol and PCE treatments reduced postmenopausal bone loss by increasing alkaline phosphatase, Ca concentrations, serum E2 concentration and bone mineral density, and by decreasing the inorganic P level. The present study indicated that bakuchiol and PCE treatments could protect against bone loss.
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Comparative effects of oral conjugated equine estrogens and micronized 17β-estradiol on breast proliferation. Menopause 2008; 15:890-8. [DOI: 10.1097/gme.0b013e318168f0ad] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Effects of hormone therapy and dietary soy on myocardial ischemia/reperfusion injury in ovariectomized atherosclerotic monkeys. Menopause 2008; 15:256-63. [PMID: 17917613 DOI: 10.1097/gme.0b013e31812e6b4a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Hormone therapy (HT) and dietary soy (Soy) inhibit myocardial ischemia/reperfusion (I/R) injury in nonatherosclerotic animals. The aim of this study was to determine their independent and interactive effects on I/R in monkeys previously fed an atherogenic diet for 15 months. DESIGN Ovariectomized atherosclerotic monkeys (n = 40) were divided into one of four dietary treatment groups: (1) casein as the protein source, (2) casein and added HT (the equivalent of 5 mug ethinyl estradiol + 1 mg norethindrone acetate daily), (3) Soy protein providing 141 mg total isoflavones daily, or (4) Soy + HT. After 12 months monkeys were anesthetized, and their left anterior descending coronary artery was occluded for 1 hour and reperfused for 4 hours. Infarct size was the percentage of the area at risk not staining with triphenyltetrazolium chloride. Additional measures were myocardial blood flow, stroke volume, coronary output, myeloperoxidase, and malondialdehyde. RESULTS There was an interactive negative effect of HT + Soy to increase infarct size from approximately 30% (in other groups) to 55% (P = 0.0004). Additionally, there were negative main effects of Soy on blood flow, coronary output, and stroke volume during I/R (all P values <0.05). There were no effects of treatment on either myeloperoxidase or malondialdehyde. CONCLUSIONS Neither HT nor Soy had beneficial effects, whereas their combination had harmful effects, on myocardial I/R injury in monkeys with preexisting atherosclerosis. The mechanism of this negative interaction remains unclear but may relate to Soy's negative effects on hemodynamics.
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Seidlová-Wuttke D, Jarry H, Jäger Y, Wuttke W. Bone development in female rats maintained with soy-free or soy-containing food as determined by computer-assisted tomography and serum bone markers. J Bone Miner Metab 2008; 26:321-7. [PMID: 18600397 DOI: 10.1007/s00774-007-0838-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Accepted: 12/22/2007] [Indexed: 10/21/2022]
Abstract
The development of bone in immature rats and in aged rats has not been thoroughly studied. Therefore, we investigated the development of bones in young, middle-aged, and aged female rats. Because most rat chows contain soy proteins, including estrogenic isoflavones, as a source of protein, comparison of effects on mineral density and on areas of the cancellous and cortical parts of the metaphysis of the tibia as measured by quantitative computer tomography in animals fed with soy-free and soy-containing food was made. As surrogate parameters of bone metabolism serum, osteocalcin (OC) and the breakdown products of bone collagen--the Crosslaps--were also determined. The cancellous density increased between day 25 after birth to reach peak bone mass at 90 days of age; in 18-and 20-month-old animals, significant reduction was observed that was more profound in the animals fed with soy-free food. Serum OC and the Crosslaps were highest in 15-day-old and lowest in 9-, 18-, and 20-month-old animals. Animals fed with soy-containing food had significantly higher osteocalcin levels at day 15 and at 9 and 18 months of age. In the aged animals, intake of soy isoflavones that have an estrogenic effect appears to exert beneficial effects as these aged animals lost less cancellous bone, as indicated by their surrogate parameters of metabolism in the serum. It is concluded that exorbitantly high bone turnover is present in immature and peripubertal rats. Raising and keeping female rats under soy-free or soy-containing conditions has marked effects on several bone parameters that are of particular relevance in aged animals.
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Affiliation(s)
- Dana Seidlová-Wuttke
- Department of Obstetrics and Gynecology, Division of Clinical and Experimental Endocrinology, University of Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany.
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Song WO, Chun OK, Hwang I, Shin HS, Kim BG, Kim KS, Lee SY, Shin D, Lee SG. Soy isoflavones as safe functional ingredients. J Med Food 2007; 10:571-80. [PMID: 18158825 DOI: 10.1089/jmf.2006.0620] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In recent years, isoflavones have increased in popularity as an alternative to estrogen therapy, particularly after the Women's Health Initiative demonstrated an increased risk of breast cancer, stroke, and heart attacks in response to estrogen and progesterone intervention. Isoflavones are heterocyclic phenols with structural similarity to estradiol-17beta and selective estrogen receptor modulators. Actions at the cellular level depend on the target tissue, receptor status of the tissue, and the level of endogenous estrogen. Clinical studies of soy-based diets evaluating the relation between soy consumption and serum lipid concentrations revealed that soy consumption significantly decreased total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels. Epidemiological studies suggest a protective effect of soy protein on breast tissue as evidenced by the lower rates of breast cancer in East Asian countries where soy is a predominant part of the diet. Soy products also alleviate menopausal symptoms by reducing hot flashes. However, whether these biological effects of soy products originated from isoflavones is not clear. Furthermore, data available from human studies on the effect of isoflavones on osteoporosis are limited, and additional studies are needed to support a role in osteoporosis prevention. To date, no adverse effects of short- or long-term use of soy proteins are known in humans, and the only adverse effects known are those reported in animals. In conclusion, isoflavones are biologically active compounds, and current data are insufficient to draw definitive conclusions regarding the use of isoflavones as an alternative to estrogen for hormone replacement in postmenopausal women. Large, long-term intervention studies examining adverse effects and disease outcomes are needed before definitive conclusion can be drawn.
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Affiliation(s)
- Won O Song
- Department of Food Science and Human Nutrition, Michigan State University, MI 48824, USA.
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Wuttke W, Jarry H, Seidlová-Wuttke D. Isoflavones--safe food additives or dangerous drugs? Ageing Res Rev 2007; 6:150-88. [PMID: 17604235 DOI: 10.1016/j.arr.2007.05.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 04/26/2007] [Accepted: 05/02/2007] [Indexed: 01/12/2023]
Abstract
The sales volume of products containing isoflavone has increased since the publication of the Women's Health Initiative. The many apparently contradictory results published on the effects of isoflavones on a variety of estrogen-regulated organs point to both beneficial as well as adverse effects on human health. It is of particular importance that psychovegetative climacteric complaints such as hot flushes are, if at all, only slightly influenced by isoflavones. The substances appear to have weak anti-osteoporotic effect. Their anti-atherosclerotic action is debatable, as not all authors find any beneficial effect on lipids. Most importantly, there is dispute as to whether isoflavones derived from soy or red clover have negative, positive or any effect at all on the mammary gland or endometrium. It is beyond any doubt that soy products may have cancer preventing properties in a variety of organs including the mammary gland. However, these properties may only be exerted if the developing organ was under the influence of isoflavones during childhood and puberty. This may also explain the often quoted "Japanese Phenomenon", the fact that breast cancer occurs to a lesser extent in Japanese women. When administered to isoflavone "inexperienced" women at the time of menopause, the phytoestrogens appear to share the same effects as estrogen used in classical preparations for hormone replacement therapy, i.e. they may stimulate the proliferation of endometrial and mammary gland tissue with at present unknown and unpredictable risk to these organs. Therefore, the following question arises for the clinician: Why should soy or red clover products containing isoflavone be recommended, if the positive effects are only negligible but the adverse effects serious?
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Affiliation(s)
- Wolfgang Wuttke
- Department of Clinical and Experimental Endocrinology, University of Goettingen, Robert-Koch-Str. 40, 37075 Goettingen, Germany.
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Cline JM. Assessing the mammary gland of nonhuman primates: effects of endogenous hormones and exogenous hormonal agents and growth factors. ACTA ACUST UNITED AC 2007; 80:126-46. [PMID: 17443713 DOI: 10.1002/bdrb.20112] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This review provides a summary of the normal biology, development, and morphology of the breast in nonhuman primates (macaques), and of the major published work addressing hormonally-induced changes in the breast of these animals. The mammary glands of macaques are anatomically, developmentally, and physiologically similar to the human breast, with similar expression of sex steroid receptors (estrogen receptors alpha and beta, progesterone receptor A and B, androgen receptors), estrogen dependent markers, and steroid metabolizing enzymes. Genetic similarity between human beings and macaques is high, varying from 95-99% depending on the sequence evaluated. Macaques develop hyperplastic and cancerous lesions of the breast spontaneously, which are similar in type and prevalence to those of human beings. They have a reproductive physiology typical of anthropoid primates, including a distinct menarche and menopause, and a 28-day menstrual cycle. These similarities give unique value to the macaque model for evaluation of the effectiveness and safety of hormonal agents. Such agents considered in this review include estrogens and progestogens, combined therapies such as oral contraceptives and post-menopausal hormone therapies, androgens, selective estrogen receptor modulators, phytoestrogens, prolactin, somatotropin, epidermal growth factor, and other novel agents with hormonal or growth factor-like activity. This review also includes a consideration of selected background changes and typical strategies and markers used for evaluation of experimentally-induced changes, including biopsy-based strategies designed to control for inter-individual variability and minimize numbers of animals used.
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Affiliation(s)
- J Mark Cline
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1040, USA.
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Rozman KK, Bhatia J, Calafat AM, Chambers C, Culty M, Etzel RA, Flaws JA, Hansen DK, Hoyer PB, Jeffery EH, Kesner JS, Marty S, Thomas JA, Umbach D. NTP-CERHR expert panel report on the reproductive and developmental toxicity of soy formula. ACTA ACUST UNITED AC 2006; 77:280-397. [PMID: 16998908 PMCID: PMC2266894 DOI: 10.1002/bdrb.20086] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Karl K Rozman
- Department of Pharmacology and Toxicology, University of Kansas Medical Center, Kansas City, KS, USA
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Appt SE, Kaplan JR, Clarkson TB, Cline JM, Christian PJ, Hoyer PB. Destruction of primordial ovarian follicles in adult cynomolgus macaques after exposure to 4-vinylcyclohexene diepoxide: a nonhuman primate model of the menopausal transition. Fertil Steril 2006; 86:1210-6. [PMID: 16952357 DOI: 10.1016/j.fertnstert.2006.05.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Revised: 05/17/2006] [Accepted: 05/17/2006] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To determine whether the 4-vinylcyclohexene diepoxide (VCD)-treated mouse menopause model, which involves accelerated atresia of primordial follicles and induces gradual ovarian failure (while sparing the ovarian stroma), can be adapted to nonhuman primates. DESIGN Controlled periclinical trial (nonhuman primates). SETTING Comparative Medicine Clinical Research Center. ANIMAL(S) Four adult female cynomolgus monkeys. INTERVENTION(S) Once-daily i.m. injections for 15 days as follows: vehicle or VCD doses of 80 mg/kg, 160 mg/kg, 250 mg/kg. Ovaries were removed 27 days after treatment, and pathological determinations were made at necropsy. MAIN OUTCOME MEASURE(S) Baseline and interim hematologic and biochemical measures, physical exams, and body weights. Follicle counts and organ evaluation at necropsy. RESULT(S) A nearly complete elimination of primordial, intermediate, primary and secondary follicles was achieved with 250 mg/kg VCD. A 50% reduction in primordial and primary follicles was observed with 160 mg/kg VCD. No effect of 80 mg/kg VCD per day was observed. Clinical health measures remained within normal range except for transient, mild increases in liver enzymes and an inflammatory response at the injection site with 250 mg/kg. Postmortem evaluations (9 months) revealed no gross or histological lesions in the organs studied. CONCLUSION(S) These results demonstrate that the monkey ovary is susceptible to VCD and that as in rodents, primordial and primary follicles are targeted selectively.
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Affiliation(s)
- Susan E Appt
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1040, USA.
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22
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Wood CE, Appt SE, Clarkson TB, Franke AA, Lees CJ, Doerge DR, Cline JM. Effects of high-dose soy isoflavones and equol on reproductive tissues in female cynomolgus monkeys. Biol Reprod 2006; 75:477-86. [PMID: 16723506 DOI: 10.1095/biolreprod.106.052142] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Soy isoflavonoids have well-established estrogenic properties in cell culture and rodent models, raising concerns that high isoflavonoid intake may promote development of uterine and breast cancers. To address this concern we evaluated the effects of high-dose isoflavonoid supplements on reproductive tissues in a postmenopausal primate model. Thirty adult female ovariectomized monkeys (Macaca fascicularis) were randomized to receive a control diet 1) alone, 2) with 509 mg/day of the soy isoflavones genistein and daidzein (IF), or 3) with 1020 mg/day of racemic equol (EQ), an isoflavan, for approximately 1 mo. Doses are expressed in aglycone units as calorically scaled human equivalents. Total serum isoflavonoid levels 4 h postfeeding were <20 nmol/L, 2570.7 nmol/L, and 6944.8 nmol/L for control, IF, and EQ groups, respectively. Equol was the predominant serum isoflavonoid in both IF (72.5%) and EQ (99.7%) groups. Aglycones represented 0.9% (IF) and 0.5% (EQ) of total serum isoflavonoids. Histologically, uteri and mammary glands were diffusely atrophic in all groups. Uterine weight, endometrial thickness, glandular area, and epithelial proliferation in the uterus were not significantly different among treatment groups (ANOVA P > 0.1 for all). Endometrial progesterone receptor gene expression was significantly increased in the IF group (P = 0.02), while protein expression was not altered (ANOVA P > 0.1). Within the mammary gland, proliferation and indicators of estrogen exposure did not differ among treatment groups (ANOVA P > 0.1 for all). These findings indicate that high doses of dietary soy isoflavonoids have minimal uterotrophic or mammotrophic effects in an established primate model.
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Affiliation(s)
- Charles E Wood
- Department of Pathology/Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1040, USA.
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Wood CE, Register TC, Franke AA, Anthony MS, Cline JM. Dietary soy isoflavones inhibit estrogen effects in the postmenopausal breast. Cancer Res 2006; 66:1241-9. [PMID: 16424064 DOI: 10.1158/0008-5472.can-05-2067] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Soy isoflavones are promising dietary agents for prevention of breast cancer. Isoflavones bind estrogen receptors (ER) and may variably act as either estrogen agonists or antagonists depending on the estrogen environment. In this study, we used a postmenopausal primate model to evaluate interactive effects of dietary soy isoflavones and estrogen on risk markers for breast cancer. The experiment followed a randomized factorial design in which 31 ovariectomized adult female cynomolgus monkeys were divided into social groups of three to four animals each and rotated through eight different diets containing the human equivalent of 0, 60, 120, or 240 mg/d soy isoflavones with a dose of oral micronized 17beta-estradiol (E(2)) corresponding to either a low (0.09 mg/d) or a high (0.5 mg/d) postmenopausal estrogen environment. Treatment periods lasted 4 months with a 1-month washout period between diets. The highest isoflavone dose resulted in significantly lower breast proliferation and uterine size in the high-estrogen environment. These effects were accompanied by divergent changes in breast markers of ER activation in which pS2 expression was significantly lower and progesterone receptor expression was significantly higher following the 240 mg isoflavone dose. All isoflavone doses resulted in lower serum estrone and E(2) concentrations in the high-estrogen environment. In contrast, isoflavone treatment had no significant estrogen agonist effects and minimal antagonistic effects in the lower-estrogen environment. These findings show that in the presence of estrogen higher doses of dietary soy isoflavones may alter ER signaling and induce selective antagonistic effects in the breast.
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Affiliation(s)
- Charles E Wood
- Department of Pathology/Section on Comparative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
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Wood CE, Clarkson TB, Appt SE, Franke AA, Boue SM, Burow ME, McCoy T, Cline JM. Effects of soybean glyceollins and estradiol in postmenopausal female monkeys. Nutr Cancer 2006; 56:74-81. [PMID: 17176220 DOI: 10.1207/s15327914nc5601_10] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Glyceollins are a novel class of soybean phytoalexins with potential cancer-protective antiestrogenic effects. The purpose of this study was to evaluate the estrogen-antagonist effects of glyceollin-enriched soy protein on biomarkers for breast cancer risk. Thirty female postmenopausal cynomolgus macaques were randomized to one of three dietary treatments for 3 wk: 1) estradiol (E2, 1 mg/day) + casein/lactalbumin (control); 2) E2 + soy protein isolate (SPI) containing 194 mg/day isoflavonoids; and 3) E2 + glyceollin-enriched soy protein (GLY) containing 189 mg/day isoflavonoids + 134 mg/day glyceollins. Doses are expressed in calorically scaled human equivalents. Mean serum glyceollin concentrations at 4 h postfeeding were 134.2 +/- 34.6 nmol/L in the GLY group and negligible in the SPI group (P = 0.0007). Breast proliferation was significantly increased in the control group (+237%, P = 0.01) but not in the SPI group (+198%, P = 0.08) or GLY group (+36%, P = 0.18). Gene expression of trefoil factor 1 and progesterone receptor, two markers of estrogen receptor activity in breast epithelium, were also significantly higher in the control (P < 0.05 for both) but not in the GLY group. These preliminary findings suggest that soybean glyceollins are natural compounds with potential estrogen-modulating properties in the breast.
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Affiliation(s)
- Charles E Wood
- Department of Pathology/Section on Comparative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
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Clarkson TB, Appt SE. Controversies about HRT--lessons from monkey models. Maturitas 2005; 51:64-74. [PMID: 15883111 DOI: 10.1016/j.maturitas.2005.02.016] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 01/18/2005] [Accepted: 01/21/2005] [Indexed: 10/25/2022]
Abstract
Lessons from monkey models contribute significantly to a better understanding of the controversies in reconciling the differences in postmenopausal hormone treatment outcomes between observational and randomized trial data. Monkey studies brought attention to premenopausal estrogen deficiency with resulting premature coronary artery atherosclerosis. Recently, those monkey studies were confirmed for premenopausal women in the NHLBI-sponsored Women's Ischemia Syndrome Evaluation (WISE) Study. Monkey studies have provided convincing evidence for the primary prevention of coronary artery atherosclerosis when estrogens are administered soon after the development of estrogen deficiency. Equally convincing are the data from monkey studies indicating the total loss of these estrogens beneficial effects if treatment is delayed for a period equal to six postmenopausal years for women. An attempt has been made using the monkey model to identify the hormone treatment regimen most effective in preventing the progression of coronary artery atherosclerosis. By a substantial margin, the most effective approach is that of using estrogen containing oral contraceptive during the perimenopausal transition, followed directly by hormone replacement therapy postmenopausally. Because of similarities between human and nonhuman breast, monkeys have had a major role in clarifying controversies surrounding the breast cancer risk of estrogen only versus estrogen plus progestin therapies. The results of monkey studies suggest little or no effects of estrogen only treatment; whereas, estrogen+progestin clearly increases breast cancer risk.
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Affiliation(s)
- Thomas B Clarkson
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157-1040, USA.
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Eason RR, Till SR, Velarde MC, Geng Y, Chatman L, Gu L, Badger TM, Simmen FA, Simmen RCM. Uterine phenotype of young adult rats exposed to dietary soy or genistein during development. J Nutr Biochem 2005; 16:625-32. [PMID: 16081271 DOI: 10.1016/j.jnutbio.2005.03.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Revised: 03/10/2005] [Accepted: 03/17/2005] [Indexed: 11/21/2022]
Abstract
Dietary soy intake is associated with protection from breast cancer, but questions persist on the potential risks of the major soy isoflavone genistein (GEN) on female reproductive health. Here, we evaluated intermediate markers of cancer risk in uteri of cycling, young adult Sprague-Dawley rats lifetime exposed to one of three AIN-93G semipurified diets: casein (CAS), soy protein isolate (SPI+ with 276 mg GEN aglycone equivalents/kg) and CAS+GEN (GEN at 250 mg/kg). Postnatal day 50 (PND50) rats lifetime exposed to GEN or SPI+ had similar uterine luminal epithelium height, myometrial thickness, endometrial gland numbers, endometrial immunoreactive proliferating cell nuclear antigen (PCNA), and serum estrogen and progesterone, as CAS-fed rats. GEN-fed rats showed modestly increased apoptosis in uterine glandular epithelium, compared to those of CAS- or SPI+-fed groups. Diet had no effect on the uterine expression of genes for the tumor suppressors PTEN, p53 and p21, and the apoptotic-associated proteins Bcl2, Bax and progesterone receptor. Uterine tissue and serum concentrations of total GEN were higher in rats fed GEN than in those fed SPI+. Human Ishikawa endocarcinoma cells treated with GEN-fed rat serum tended to exhibit increased apoptotic status than those treated with CAS-fed rat serum. Exogenously added GEN (0.2 and 2 microM) increased, while estradiol-17beta (0.1 microM) decreased Ishikawa cell apoptosis, relative to untreated cells. Results suggest that lifetime dietary exposure to soy foods does not alter uterine cell phenotype in young adult rats, while GEN, by enhancing uterine endometrial glandular apoptosis in vivo and in vitro, may confer protection against uterine carcinoma. Given its limited influence on uterine phenotype of young adult females, GEN, when taken as part of soy foods or as supplement, should be favorably considered for other potential health benefits.
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Affiliation(s)
- Renea R Eason
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR 72202, USA
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Guo TL, Auttachoat W, Chi RP. Genistein enhancement of respiratory allergen trimellitic anhydride-induced IgE production by adult B6C3F1 mice following in utero and postnatal exposure. Toxicol Sci 2005; 87:399-408. [PMID: 16049267 PMCID: PMC1351224 DOI: 10.1093/toxsci/kfi268] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The objective of the present study was to determine if exposure to the phytoestrogen genistein (GEN) during immune development had any effects on the production of IgE by adult mice following dermal treatment with trimellitic anhydride (TMA), a respiratory allergen. B6C3F1 mice were exposed to GEN either by feeding at 500 ppm or by gavage (20 mg/kg) for varied periods from gestation day (GD) 14 to postnatal day (PND) 84. In utero exposure to GEN by feeding increased the production of IgE at PND 84 in male mice but not in female mice. In male mice, continuous exposure to GEN postnatally diminished the in utero exposure-induced enhancement in serum total IgE production. However, continuous exposure to GEN from GD 14 to PND 84 was required to increase serum total IgE production in female mice. In utero exposure to GEN by gavage increased the production of IgE at PND 84 in female mice but not in male mice when the mice were maintained on the NIH-07 rodent diet in which a medium level of phytoestrogens was present. The enhancement in IgE production after GEN exposure in females but not in males was associated with decreases in the percentages of CD4(+)CD25(+) T suppressor cells, and increases in the natural killer (NK) cell activity, the basal splenocyte proliferation, the expression of CD86 by B cells, and the production of IL-2 and IL-4. Overall, the results demonstrated that GEN differentially modulated the developing immune system in male and female mice, and that more IgE was produced upon exposure to TMA in the adult.
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Affiliation(s)
- Tai L Guo
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, 23298-0613, USA.
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Isoflavonas y menopausia. CLINICA E INVESTIGACION EN GINECOLOGIA Y OBSTETRICIA 2005. [DOI: 10.1016/s0210-573x(05)73483-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Foth D, Nawroth F. Effect of phytoestrogens on the endometrium? Fertil Steril 2005; 83:256-7; author reply 257. [PMID: 15652928 DOI: 10.1016/j.fertnstert.2004.10.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2004] [Indexed: 11/19/2022]
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