Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Physiology

Brigham Young University

Phytoestrogens

Articles 1 - 7 of 7

Full-Text Articles in Life Sciences

The Effects Of Prenatally Administered Phytoestrogens On The Reproductive And Behavioral Development Of Long-Evans Rats, Crystal Blake Mar 2008

The Effects Of Prenatally Administered Phytoestrogens On The Reproductive And Behavioral Development Of Long-Evans Rats, Crystal Blake

Theses and Dissertations

Equol is known to be a selective androgen modulator and has the ability to bind and inhibit 5-alpha dihydrotestosterone (5α-DHT). Equol is also a selective estrogen receptor modulator and is able to bind beta estrogen receptors with high affinity. As estrogen receptors are found in the hypothalamus, pituitary, and gonads, prenatally administered equol could affect the morphological and reproductive development of offspring. To test this hypothesis, during gestational days 14 to 20, forty-two pregnant Long-Evans rats were given one of six treatments: 1) no treatment, 2) injection with dimethyl sulfoxide (DMSO), 3) injection with 10 mg/kg equol, 4) injection with …


Avpv Neurons Containing Estrogen Receptor-Beta In Adult Male Rats Are Influenced By Soy Isoflavones, Edwin D. Lephart, Lihong H. Bu Feb 2007

Avpv Neurons Containing Estrogen Receptor-Beta In Adult Male Rats Are Influenced By Soy Isoflavones, Edwin D. Lephart, Lihong H. Bu

Faculty Publications

Background Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. It is known that 17beta-estradiol induces apoptosis in anteroventral periventricular nucleus (AVPV) in rat brain. Also, there is evidence that consumption of soy isoflavones reduces the volume of AVPV in male rats. Therefore, in this study, we examined the influence of dietary soy isoflavones on apoptosis in AVPV of 150 day-old male rats fed either a soy isoflavone-free diet (Phyto-free) or a soy isoflavone-rich diet (Phyto-600). Results: The occurrence of apoptosis in AVPV was examined by TUNEL staining. The incidence of apoptosis was about 10 times …


Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell Oct 2005

Influences Of Dietary Soy Isoflavones On Metabolism But Not Nociception And Stress Hormone Responses In Ovariectomized Female Rats, Edwin D. Lephart, Lihong H. Bu, Kenneth Setchell

Faculty Publications

Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. Methods: In this study, ovariectomized (OVX) female Long-Evans rats were fed either an isoflavone-rich diet (Phyto-600) or an isoflavone-free diet (Phyto-free). We examined the effects of soy isoflavones on metabolism by measuring body weights, food/water intake, adipose tissue weights as well as serum leptin levels. Also, circulating isoflavone levels were quantified. During chemically induced estrous, nociceptive thresholds were recorded. Then, the animals were subjected to a stressor and stress hormone levels were …


Dietary Isoflavones Alter Regulatory Behaviors, Metabolic Hormones And Neuroendocrine Function In Long-Evans Male Rats, Edwin D. Lephart, James P. Proter, Lihong H. Bu, Trent D. Lund, Kenneth Setchell, Gina Ramoz, William R. Crowley Dec 2004

Dietary Isoflavones Alter Regulatory Behaviors, Metabolic Hormones And Neuroendocrine Function In Long-Evans Male Rats, Edwin D. Lephart, James P. Proter, Lihong H. Bu, Trent D. Lund, Kenneth Setchell, Gina Ramoz, William R. Crowley

Faculty Publications

Phytoestrogens derived from soy foods (or isoflavones) have received prevalent usage due to their 'health benefits' of decreasing: a) age-related diseases, b) hormone-dependent cancers and c) postmenopausal symptoms. However, little is known about the influence of dietary phytoestrogens on regulatory behaviors, such as food and water intake, metabolic hormones and neuroendocrine parameters. This study examined important hormonal and metabolic health issues by testing the hypotheses that dietary soy-derived isoflavones influence: 1) body weight and adipose deposition, 2) food and water intake, 3) metabolic hormones (i.e., leptin, insulin, T3 and glucose levels), 4) brain neuropeptide Y (NPY) levels, 5) heat production …


Androgen Receptor Expression In The Rat Prostate Is Down-Regulated By Dietary Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Daniel J. Munson, Herman Aldercreutz, Robert J. Handa Jan 2004

Androgen Receptor Expression In The Rat Prostate Is Down-Regulated By Dietary Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Daniel J. Munson, Herman Aldercreutz, Robert J. Handa

Faculty Publications

Background- It is well established that the growth of the prostate gland is a hormone-dependent phenomenon involving both androgenic and estrogenic control. Proliferation of prostate cells is, at least in part, under control of estrogen receptor beta (ER-beta). Phytoestrogens bind ER-beta with high affinity and therefore may have antiproliferative effects in the prostate. Methods- The prostates of male Long-Evans rats fed a diet high in phytoestrogens (Phyto-600) or very low levels of phytoestrogens (Phyto-free) were analyzed to determine the impact of dietary phytoestrogens on prostate weight and androgen receptor (AR) expression in the prostate. Results- Dietary phytoestrogens significantly decreased post-pubertal …


Manipulation Of Prenatal Hormones And Dietary Phytoestrogens During Adulthood Alter The Sexually Dimorphic Expression Of Visual Spatial Memory, Edwin D. Lephart, Trent D. Lund Dec 2001

Manipulation Of Prenatal Hormones And Dietary Phytoestrogens During Adulthood Alter The Sexually Dimorphic Expression Of Visual Spatial Memory, Edwin D. Lephart, Trent D. Lund

Faculty Publications

In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit higher performance levels compared to females (a difference attributed to sex steroid hormonal influences). Based upon the results from our companion investigation, this study examined the influence of prenatal sex steroid hormone manipulations on VSM in adulthood, as assessed in the radial arm maze. Additionally, the influence of dietary soy phytoestrogens (i.e., the presence of high or low estrogen-like compounds present in the animal's diet) on VSM was examined in combination with the prenatal hormonal manipulations. Results: Radial arm maze performance on a phytoestrogen-rich diet: 1) females treated …


Visual Spatial Memory Is Enhanced In Female Rats (But Inhibited In Males) By Dietary Soy Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Timothy W. West, Lilyan Y. Tian, Lihong H. Bu, Daniel L. Simmons, Kenneth Setchell, Herman Adlercreutz Dec 2001

Visual Spatial Memory Is Enhanced In Female Rats (But Inhibited In Males) By Dietary Soy Phytoestrogens, Edwin D. Lephart, Trent D. Lund, Timothy W. West, Lilyan Y. Tian, Lihong H. Bu, Daniel L. Simmons, Kenneth Setchell, Herman Adlercreutz

Faculty Publications

In learning and memory tasks, requiring visual spatial memory (VSM), males exhibit superior performance to females (a difference attributed to the hormonal influence of estrogen). This study examined the influence of phytoestrogens (estrogen-like plant compounds) on VSM, utilizing radial arm-maze methods to examine varying aspects of memory. Additionally, brain phytoestrogen, calbindin (CALB), and cyclooxygenase-2 (COX-2) levels were determined. Results: Female rats receiving lifelong exposure to a high-phytoestrogen containing diet (Phyto-600) acquired the maze faster than females fed a phytoestrogen-free diet (Phyto-free); in males the opposite diet effect was identified. In a separate experiment, at 80 days-of-age, animals fed the Phyto-600 …