Carbohydrate metabolism in erythrocytes of copper deficient rats.

Dietary copper deficiency is known to adversely affect the circulatory system of fructose-fed rats. Part of the problem may lie in the effect of copper deficiency on intermediary metabolism. To test this, weanling male Long-Evans rats were fed for 4 or 8 weeks on sucrose-based diets containing low or adequate copper content. Copper deficient rats had significantly lower plasma and tissue copper as well as lower plasma copper, zinc-superoxide dismutase activity. Copper deficient rats also had a significantly higher heart:body weight ratio when compared to pair-fed controls. Direct measurement of glycolysis and pentose phosphate pathway flux in erythrocytes using (13)C NMR showed no differences in carbon flux from glucose or fructose to pyruvate but a significantly higher flux through the lactate dehydrogenase locus in copper deficient rats (approximately 1.3 times, average of glucose and glucose + fructose measurements). Copper-deficient animals had significantly higher erythrocyte concentrations of glucose, fructose, glyceraldehyde 3-phosphate and NAD(+). Liver metabolite levels were also affected by copper deficiency being elevated in glycogen and fructose 1-phosphate content. The results show small changes in carbohydrate metabolism of copper deficient rats.

Effect of raloxifene on sexual function in postmenopausal women.

OBJECTIVE: To determine the effects of raloxifene on sexual function in postmenopausal women with pre-existing vaginal atrophy treated with vaginal estrogen cream. METHODS: A total of 187 naturally postmenopausal women, 42-80 years of age, with signs of genitourinary atrophy were enrolled in this 6-month, multicenter, parallel-group study. Subjects were randomized to oral raloxifene HCl 60 mg daily or matching placebo; the same subjects were also randomized to receive one application of either vaginal conjugated estrogen cream 0.5 g twice weekly for 6 months or non-hormonal vaginal moisturizer twice weekly for 3 months, followed by conjugated estrogen cream for 3 months. Both investigators and subjects were masked to the identity of the oral medication. The vaginal preparations were administered in an open-label fashion. The Sexual Activity Questionnaire (SAQ) was administered at baseline and at 3 and 6 months. Safety was assessed throughout the study. RESULTS: A total of 102 women were sexually active at baseline and, of these, 82 were also sexually active at the 6-month end-point. At 6 months, raloxifene and placebo, in the presence of vaginal conjugated estrogen cream, were both associated with improvement from baseline in vaginal dryness and reduced discomfort during sexual activity. There were no significant differences between raloxifene and placebo groups in any SAQ item. Enjoyment of sexual activity significantly increased from baseline with raloxifene but not with placebo. No difference in adverse events was observed between groups. CONCLUSION: Raloxifene had no negative effects on sexual function in postmenopausal women with vaginal atrophy who were treated concomitantly with vaginal estrogen cream.

Comparative health effects of margarines fortified with plant sterols and stanols on a rat model for hemorrhagic stroke.

There is increased acceptance of fortifying habitual foods with plant sterols and their saturated derivatives, stanols, at levels that are considered safe. These sterols and stanols are recognized as potentially effective dietary components for lowering plasma total and LDL cholesterol. Our previous studies have shown that daily consumption of plant sterols promotes strokes and shortens the life span of stroke-prone spontaneously hypertensive (SHRSP) rats. These studies question the safety of plant sterol additives. The present study was performed to determine whether a large intake of plant stanols would cause nutritional effects similar to those seen with plant sterols in SHRSP rats. Young SHRSP rats (aged 26-29 d) were fed semipurified diets containing commercial margarines fortified with either plant stanols (1.1 g/100 g diet) or plant sterols (1.4 g/100 g diet). A reference group of SHRSP rats was fed a soybean oil diet (0.02 g plant sterols/100 g diet and no plant stanols). Compared to soybean oil, both plant stanol and plant sterol margarines significantly (P < 0.05) reduced the life span of SHRSP rats. At the initial stages of feeding, there was no difference in the survival rates between the two margarine groups, but after approximately 50 d of feeding, the plant stanol group had a slightly, but significantly (P < 0.05), lower survival rate. Blood and tissue (plasma, red blood cells, liver, and kidney) concentrations of plant sterols in the plant sterol margarine group were three to four times higher than the corresponding tissue concentrations of plant stanols in the plant stanol group. The deformability of red blood cells and the platelet count of SHRSP rats fed the plant sterol margarine were significantly (P < 0.05) lower than those of the plant stanol margarine and soybean oil groups at the end of the study. These parameters did not differ between the soybean oil and plant stanol margarine groups. These results suggest that, at the levels tested in the present study, plant stanols provoke hemorrhagic stroke in SHRSP rats to a slightly greater extent than plant sterols. The results also suggest that the mechanism by which plant stanols shorten the life span of SHRSP rats might differ from that of plant sterols.

Raloxifene effect on frequency of surgery for pelvic floor relaxation.

OBJECTIVE: To assess the effects of raloxifene therapy on the frequency of surgery for pelvic floor relaxation in postmenopausal women. METHODS: This analysis used safety data through 3 years of treatment from three double-masked, placebo-controlled, randomized trials of raloxifene, which included 6926 postmenopausal women with uteri at entry. Studies 1 and 2 enrolled 969 nonosteoporotic, postmenopausal women who were assigned to 30, 60, or 150 mg per day raloxifene or placebo. Study 3 enrolled 5957 osteoporotic, postmenopausal women randomized to raloxifene 60 or 120 mg per day or placebo. Indications for any reported pelvic operations were identified, including procedures performed for pelvic organ prolapse or urinary incontinence. RESULTS: A total of 34 (1.51%) women in the placebo group and 35 (0.75%) raloxifene-treated women underwent surgical procedures for pelvic floor relaxation. The odds ratio (and 95% confidence interval) for pelvic floor repair in women assigned to raloxifene was 0.50 (0.31, 0.81). Thus, raloxifene therapy was associated with a significantly reduced risk for pelvic floor surgery (P <.005). CONCLUSION: Raloxifene does not increase pelvic floor relaxation. An apparent protective effect on pelvic floor function warrants further investigation.

The effect of selective estrogen receptor modulators on parameters of the hypothalamic-pituitary-gonadal axis.

The SERMs currently in clinical practice or in late stages of clinical development have been studied primarily for their effects on the breast, cardiovascular, bone, and reproductive systems. The effect of SERMs on the hypothalamic-pituitary-gonadal (HPG) axis has not been the primary focus of the studies conducted thus far. However the effect of SERMs on the HPG axis and the associated regulation of endocrine parameters may play an important role in their overall clinical profile. In this review the effects of selected SERMs on the HPG axis in premenopausal women, postmenopausal women, and men are summarized.

Influence of sources of dietary oils on the life span of stroke-prone spontaneously hypertensive rats.

In recent studies, the life span of stroke-prone spontaneously hypertensive (SHRSP) rats was altered by a variety of dietary fats. It was relatively shorter in rats fed canola oil as the sole source of fat. The present study was performed to find out whether the fatty acid profile and the high content of sulfur compounds in canola oil could modulate the life span of SHRSP rats. SHRSP rats (47 d old, n = 23/group) were matched by body weight and systolic blood pressure and fed semipurified diets containing 10% canola oil, high-palmitic canola oil, low-sulfur canola oil, soybean oil, high-oleic safflower oil, a fat blend that mimicked the fatty acid composition of canola oil, or a fat blend high in saturated fatty acids. A 1% sodium chloride solution was used as drinking water to induce hypertension. After consuming the diets for 37 d, five rats from each dietary group were killed for collection of blood and tissue samples for biochemical analysis. The 18 remaining animals from each group were used for determining their life span. The mean survival time of SHRSP rats fed canola oil (87.4+/-4.0 d) was not significantly different (P > 0.05) from those fed low-sulfur canola oil (89.7+/-8.5 d), suggesting that content of sulfur in canola oil has no effect on the life span of SHRSP rats. The SHRSP rats fed the noncanola oil-based diets lived longer (mean survival time difference was 6-13 d, P < 0.05) than those fed canola and low-sulfur canola oils. No marked differences in the survival times were observed among the noncanola oil-based groups. The fatty acid composition of the dietary oils and of red blood cells and liver of SHRSP rats killed after 37 d of treatment showed no relationship with the survival times. These results suggest that the fatty acid profile of vegetable oils plays no important role on the life span of SHRSP rat. However, phytosterols in the dietary oils and in liver and brain were inversely correlated with the mean survival times,indicating that the differential effects of vegetable oils might be ascribed, at least partly, to their different phytosterol contents.

A pharmacological review of selective oestrogen receptor modulators.

Selective oestrogen receptor modulators (SERMs) are structurally diverse non-steroidal compounds that bind to oestrogen receptors and produce oestrogen agonist effects in some tissues and oestrogen antagonist effects in others. SERMs are being evaluated for a number of oestrogen-related diseases, including post-menopausal osteoporosis, hormone-dependent cancers, and cardiovascular disease. Several compounds that exhibit a SERM profile are currently available for clinical use, including clomiphene, tamoxifen, and toremifene (which are triphenylethylenes) and raloxifene (a benzothiophene). Clomiphene is used for the induction of ovulation in sub-fertile women attempting pregnancy. Tamoxifen and toremifene are both used to treat breast cancer. Tamoxifen may have beneficial effects on bone mineral density and serum lipids. The effects of toremifene on serum lipids are similar to that of tamoxifen. Both compounds have stimulatory effects on the endometrium. Raloxifene, indicated for the treatment and prevention of post-menopausal osteoporosis, has beneficial effects on bone mineral density and serum lipids, but does not increase the risk of endometrial hyperplasia or endometrial cancer. Recently, raloxifene was shown to reduce the incidence of vertebral fractures in otherwise healthy women with osteoporosis; in the same study, a reduced incidence of breast cancer was also observed. Similar to oestrogens, SERMs increase the incidence of venous thromboembolism. Several newer compounds that exhibit a SERM profile are also in clinical development, including other triphenylethylenes (droloxifene, idoxifene) and benzothiophenes (LY353381.HCl), benzopyrans (EM-800), and naphthalenes (CP-336,156).

Vegetable oils high in phytosterols make erythrocytes less deformable and shorten the life span of stroke-prone spontaneously hypertensive rats.

Previous studies have shown that canola oil (CA), compared with soybean oil (SO), shortens the life span of stroke-prone spontaneously hypertensive (SHRSP) rats, a widely used model for hemorrhagic stroke. SHRSP rats are highly sensitive to dietary cholesterol manipulations because a deficiency of membrane cholesterol makes their cell membranes weak and fragile. Phytosterols, abundant in CA but not in SO, can inhibit the absorption of cholesterol and also replace a part of cholesterol in cell membranes. This study was performed to determine whether the high concentration of phytosterols in CA might account for its life-shortening effect on SHRSP rats. Male, 35-d-old SHRSP rats (n = 28/group) were fed semipurified diets containing CA, SO, CA fortified with phytosterols (canola oil + phytosterols, CA + P), SO fortified with phytosterols (soybean oil + phytosterols, SO + P), corn oil (CO), olive oil (OO) or a fat blend that mimicked the fat composition of a representative Canadian diet (Canadian fat mimic, CFM; 10 g/100 g diet). These fats provided 97, 36, 207, 201, 114, 27 and 27 mg phytosterols/100 g diet, respectively. Ten rats from each group were killed after 30-32 d for blood and tissue analyses. The remaining rats (18/group) were used for determination of life span. The life span of SHRSP rats fed the high phytosterol oils (CA, CA + P, SO + P and CO) was significantly (P<0.05) shorter than that of CFM- and SO-fed rats. At 30-32 d, the groups fed the high phytosterol oils had greater levels of phytosterols and significantly (P<0.05) higher ratios of phytosterols/cholesterol in plasma, RBC, liver and kidney, and a significantly (P<0.05) lower RBC membrane deformabilty index than the groups fed oils low in phytosterols (SO, OO and CFM). The mean survival times were correlated with RBC deformability index (r(2) = 0.91, P = 0.0033) and cholesterol concentration (r(2) = 0.94, P = 0.0016), and inversely correlated with RBC phytosterol concentration (r(2) = 0.58, P = 0.0798) and phytosterols/cholesterol (r(2) = 0.65, P = 0.0579), except in the OO group. This study suggests that the high concentration of phytosterols in CA and the addition of phytosterols to other fats make the cell membrane more rigid, which might be a factor contributing to the shortened life span of SHRSP rats.

Selective estrogen receptor modulators (SERMs) in clinical practice.

The objective of this literature review is to familiarize the reader with the clinical data on selective estrogen receptor modulators (SERMs) and antiestrogens currently in use in the US, excluding data on breast effects. Four compounds in the SERM and antiestrogen families are presently in clinical use in the US: clomiphene (CC), tamoxifen (TAM), toremifene (TOR), and raloxifene (RLX). The clinical database on these compounds is among the largest available. Each compound demonstrates a specific profile for its target tissue effects, and this may differ between premenopausal and postmenopausal women. CC is the most widely used agent for ovulation induction. TAM is indicated in the management of breast cancer and for prevention in women at high risk. TAM may have additional effects on the cardiovascular and skeletal systems. TOR also is used for its effects on breast tissue and may have positive cardiovascular effects. RLX is approved in the management of osteoporosis with data supporting favorable effects on the cardiovascular system and breast tissue. TAM and TOR appear to have stimulatory effects on the uterus and endometrium, whereas RLX is neutral. Few adverse events have been attributed to these agents, with hot flashes being the most common one. There appears to be an increased risk of thromboembolic events with continuous use of TAM, TOR, and RLX. SERMs and antiestrogens continue to be studied extensively. Their evolving profiles support key roles for these agents in modern day medicine, particularly in the management of postmenopausal women's health.

Disorders of excessive hair growth in the adolescent.

Virilization is most often the reflection of a serious underlying condition. Diagnosis and management should be prompt, thorough, and comprehensive. Hirsutism is the manifestation of a variety of disorders. It may be associated with serious acute medical conditions, chronic disorders, or idiopathic. The diagnosis should be methodical and adjusted to the nature of the clinical presentation. Several therapeutic modalities are effective and produce satisfactory results for most patients.

Uterine effects of 3-year raloxifene therapy in postmenopausal women younger than age 60.

OBJECTIVE: To assess the uterine effects of 3 years of therapy with raloxifene in healthy, postmenopausal women under age 60. METHODS: Integrated data from two identically designed, randomized, double-masked, placebo-controlled clinical trials were analyzed. Nine hundred sixty-nine healthy women with uteri (ages 45 through 60, 2 to 8 years postmenopausal) were assigned randomly to raloxifene 30, 60, or 150 mg per day, or an identical placebo for 3 years. Endometrial thickness was evaluated with transvaginal ultrasonography every 6 months for 2 years and again after 3 years. Further uterine evaluation, including endometrial sampling if necessary, was initiated for vaginal bleeding or findings of endometrial thickness greater than 5 mm. RESULTS: Endometrial thickness was unchanged by raloxifene and not significantly different from placebo at any time. One hundred seventy-two women had at least one episode of endometrial thickness greater than 5 mm or vaginal bleeding distributed equally among all groups. A total of 102 (10.5%) women underwent endometrial sampling at least once: 15 (1.5%) for vaginal bleeding, 78 (8.0%) for endometrial thickness greater than 5 mm, and nine (0.9%) for other reasons. There were no significant treatment differences in the proportion of women sampled, in the clinical findings, or in the histologic diagnoses. CONCLUSION: Raloxifene given to healthy postmenopausal women at doses from 30 to 150 mg per day does not stimulate uterine growth and does not cause vaginal bleeding, spotting, or discharge through 3 years of therapy. Thus, any bleeding during therapy should be deemed unexpected and prompt a clinical evaluation.

Healthcare use among U.S. women aged 45 and older: total costs and costs for selected postmenopausal health risks.

The purpose of this study is to estimate the level of healthcare use and costs incurred by postmenopausal women overall and for these selected conditions: cardiovascular disease, osteoporosis, breast cancer, and gynecological cancers. National healthcare survey and discharge data were used to estimate healthcare use by women aged 45 and older. Clinical Classification for Health Policy Research (CCHPR) codes were used to identify patients whose primary diagnosis or procedure corresponded with the selected conditions. National weights were used to estimate resource use. Treatment costs were estimated using cost/charge ratios or the Medicare fee schedule to calculate costs for each individual procedure. Estimated total annual medical care treatment costs for women 45 and older were about $186 billion in 1997 dollars, including about $60.4 billion for cardiovascular disease, $12.9 billion for osteoporosis, and $5.0 billion for breast and gynecological cancers. For each condition, estimated resource use and costs are reported for hospitalization, outpatient, nursing home, and home healthcare services. Resource use and costs are also reported by age and expected source of payment. The economic burden of disease for conditions commonly affecting postmenopausal women is substantial. Prior research establishes that hormone replacement therapy (HRT) may be effective in reducing the burden of disease among women who continue preventive therapy for many years, but few at-risk women do so. New alternatives for prevention, such as selective estrogen receptor modulators (SERMs), may be effective in reducing the burden of disease among postmenopausal women.

Endometrial response to raloxifene compared with placebo, cyclical hormone replacement therapy, and unopposed estrogen in postmenopausal women.

OBJECTIVE: To determine the endometrial effects of raloxifene 60 mg/day in postmenopausal women as assessed by vaginal bleeding and endometrial thickness. DESIGN: Data from 1157 postmenopausal women were analyzed from a database consisting of four independent, double-blind, randomized, placebo-controlled trials (range = 6-30 months duration), a 24-month open-label randomized, cyclical hormone replacement therapy (HRT)-controlled trial, and a 6-month double-blind, randomized, unopposed estrogen-controlled trial. Vaginal bleeding rate was derived from self-reported adverse events collected at least every 6 months. Endometrial thickness was measured by ultrasonography at regular intervals. RESULTS: Raloxifene 60 mg/day was not significantly different from placebo with regard to the incidence of vaginal bleeding, the baseline-to-endpoint change in endometrial thickness, or the proportion of women experiencing an increase in endometrial thickness above baseline after either 12 or 24 months of therapy. Unexpected bleeding was reported significantly more frequently in the unopposed estrogen groups compared with the raloxifene group (raloxifene 60 mg/day, 0% versus estrogen, 50%; p = 0.002). A significantly greater baseline-to-endpoint increase in endometrial thickness was observed in both the HRT and estrogen groups compared with their respective raloxifene comparison group (raloxifene 60 mg/day, 0.01 +/- 2.0 mm versus HRT, 1.8 +/- 3.2; p < 0.001; raloxifene 60 mg/day, 1.1 +/- 1.7 mm versus estrogen, 7.8 +/- 3.8; p < 0.001). No cases of endometrial hyperplasia or cancer were diagnosed in the placebo or raloxifene 60 mg/day groups. Endometrial hyperplasia was diagnosed in one case in the HRT group and in two cases in the estrogen group. CONCLUSION: Raloxifene 60 mg/day for up to 30 months is not associated with vaginal bleeding or increased endometrial thickness in postmenopausal women.

Prostaglandin F(2alpha) induces a rapid decline in progesterone production and steroidogenic acute regulatory protein expression in isolated rat corpus luteum without altering messenger ribonucleic acid expression.

With interest in steroidogenic acute regulatory protein (StAR) involvement in the luteolytic process, we studied changes in serum progesterone levels and the concomitant expression of StAR mRNA and protein (37-, 32-, and 30-kDa forms) in postovulatory Day 7 corpora lutea (CL) isolated from rats 1 h after injection with prostaglandin F(2alpha) (PGF(2alpha), n = 6) or saline (n = 6). Serum progesterone levels were determined by RIA, StAR and beta-actin mRNA expression by Northern analysis, and StAR and beta-actin protein expression by Western analysis. Adrenal, brain, and spleen from control animals were used as positive and negative controls for StAR expression. Scanning optical densitometry measurements were standardized by dividing the signal strength from each StAR autoradiogram lane by that from the corresponding beta-actin autoradiogram lane. ANOVA was used for significance testing, with alpha set at 0.05. The 37-, 32-, and 30-kDa forms of StAR protein were expressed in all adrenal samples, whereas only the 37- and 30-kDa forms were found in CL. Serum progesterone levels and expression of the 30-kDa and 37-kDa forms of the StAR protein in CL were all found to be significantly lower in the PGF(2alpha)-treated than the saline-treated group. StAR mRNA expression was not significantly different in the saline- and PGF(2alpha)-treated rats. The rapid decline in StAR protein expression that accompanies PGF(2alpha) induced luteolysis, therefore, does not result from significant decline in mRNA expression.

Adverse events reported by postmenopausal women in controlled trials with raloxifene.

OBJECTIVE: To assess the incidence of adverse events in postmenopausal women treated with raloxifene compared with placebo, hormone replacement therapy (HRT), or unopposed estrogen. METHODS: Common treatment groups were pooled across eight randomized, parallel clinical trials (6-30 months' duration) of raloxifene to create the following three databases: placebo-controlled, HRT-controlled, and estrogen-controlled databases. Incidence and severity of all treatment-emergent adverse events, defined as events that first occurred or worsened during treatment, were compared among groups in each of the databases. RESULTS: Discontinuation rates overall, and those related to adverse events, were not significantly different between treatment groups in any database. There was no significant difference in incidence of vaginal bleeding or breast discomfort between women treated with raloxifene (60 mg/d) or placebo. Both of these events were reported more frequently in women receiving HRT or estrogen. Vaginal bleeding was responsible for significantly more discontinuations from the HRT groups compared with the raloxifene group. Hot flashes was the only event common to all three databases that was significantly increased in the raloxifene group, but this event did not increase the discontinuation rates. The incidence of leg cramps was greater in raloxifene-treated women compared with placebo-treated women in the placebo-controlled database, but did not cause any discontinuations of therapy. Raloxifene had no effect on the incidence of vaginal symptoms or central nervous system events. CONCLUSION: Raloxifene had an adverse event profile distinct from HRT and unopposed estrogen and was well tolerated by postmenopausal women.

Ovaries, androgens and the menopause: practical applications.

The ovaries are a major site of production of circulating androgens during the postmenopausal years. This includes the production of testosterone. Bilateral oophorectomy can lead to a reduction in circulating testosterone levels of nearly fifty percent. Several experimental conditions have confirmed that the postmenopausal ovarian androgen production is regulated through gonadotropins and that exogenous hormones can modulate this androgen production. The function of the postmenopausal ovaries must be considered in light of these data. This body of information introduces an important consideration in the debate over elective oophorectomy at the time of unrelated gynecologic surgery.

Androgen effects on the central nervous system in the postmenopausal woman.

Interest in the effects of androgens on the central nervous system (CNS) in postmenopausal women dates back to at least fifty years. The mechanisms of action of androgens on the CNS are extremely complex and multi-faceted. Much data has been accumulated in recent years that suggest a beneficial role of androgens in several aspects of CNS function. These include positive effects on mood, cognition, memory, and libido. The information continues to be preliminary in nature and requires further investigations. There is evidence of altered androgen metabolism triggered by exogenous postmenopausal estrogen therapy. While promising, the current body of evidence does not yet support the routine addition of androgens to postmenopausal hormone therapy.