Menopause and post-menopause

Cimicifuga racemosa isopropanolic extract for menopausal symptoms: an observational prospective case-control study

OBJECTIVE

We aimed to investigate the effectiveness of isopropanolic extract of Cimicifuga Racemosa (iCR) on reducing menopausal symptoms.

MATERIALS AND METHODS

A single-center observational prospective case-control study was performed to assess the improvement of menopausal symptoms in menopausal women undergone iCR administration (cases) or no treatment (controls). Menopausal symptoms were assessed through a modified version of the Menopause Rating Scale questionnaire (mMRS) at T₀ (baseline), T₁ (1-month follow-up), and T₂ (3 months follow-up). Univariate comparisons between cases and controls were performed by using the unpaired T test for two-tailed P value with α = 0.05 significance level.

RESULTS

A total of 163 women (83 cases and 80 controls) were enrolled in the study. The difference in menopausal symptoms between cases and controls from T₀ to T₂, and from T₀ to T₁, was found significant for all analyses. In particular, the difference in all menopausal symptoms was 20.56 ± 0.90 points (95%CI: 18.77-22.33, p < .001) from T₀ to T₂, and 10.69 ± 0.6 (95%CI: 9.49-11.88, p < .001) from T₀ to T₁.

CONCLUSION

iCR may be effective in reducing menopausal symptoms, both after 1 month and after 3 months of treatment. The improvement was higher in vasomotor symptoms, sleep problems, and irritability.

Identification of Steroidogenic Components Derived From Gardenia jasminoides Ellis Potentially Useful for Treating Postmenopausal Syndrome

Estrogen-stimulating principles have been demonstrated to relieve postmenopausal syndrome effectively. Gardenia jasminoides Ellis (GJE) is an herbal medicine possessing multiple pharmacological effects on human health with low toxicity. However, the therapeutic effects of GJE on the management of postmenopausal syndrome and its mechanism of action have not been fully elucidated. In this study, network pharmacology-based approaches were employed to examine steroidogenesis under the influence of GJE. In addition, the possibility of toxicity of GJE was ruled out and four probable active compounds were predicted. In parallel, a chromatographic fraction of GJE with estrogen-stimulating effect was identified and nine major compounds were isolated from this active fraction. Among the nine compounds, four of them were identified by network pharmacology, validating the use of network pharmacology to predict active compounds. Then the phenotypic approaches were utilized to verify that rutin, chlorogenic acid (CGA) and geniposidic acid (GA) exerted an estrogen-stimulating effect on ovarian granulosa cells. Furthermore, the results of target-based approaches indicated that rutin, CGA, and GA could up-regulate the FSHR-aromatase pathway in ovarian granulosa cells. The stimulation of estrogen production by rat ovarian granulosa cells under the influence of the three compounds underwent a decline when the follicle-stimulating hormone receptor (FSHR) was blocked by antibodies against the receptor, indicating the involvement of FSHR in the estradiol-stimulating activity of the three compounds. The effects of the three compounds on estrogen biosynthesis- related gene expression level were further confirmed by Western blot assay. Importantly, the MTT results showed that exposure of breast cancer cells to the three compounds resulted in reduction of cell viability, demonstrating the cytotoxicity of the three compounds. Collectively, rutin, chlorogenic acid and geniposidic acid may contribute to the therapeutic potential of GJE for the treatment of postmenopausal syndrome.

Stress responsiveness of the hypothalamic-pituitary-adrenal axis: age-related features of the vasopressinergic regulation

The hypothalamic-pituitary-adrenal (HPA) axis plays a key role in adaptation to environmental stresses. Parvicellular neurons of the hypothalamic paraventricular nucleus secrete corticotrophin releasing hormone (CRH) and arginine vasopressin (AVP) into pituitary portal system; CRH and AVP stimulate adrenocorticotropic hormone (ACTH) release through specific G-protein-coupled membrane receptors on pituitary corticotrophs, CRHR1 for CRH and V1b for AVP; the adrenal gland cortex secretes glucocorticoids in response to ACTH. The glucocorticoids activate specific receptors in brain and peripheral tissues thereby triggering the necessary metabolic, immune, neuromodulatory, and behavioral changes to resist stress. While importance of CRH, as a key hypothalamic factor of HPA axis regulation in basal and stress conditions in most species, is generally recognized, role of AVP remains to be clarified. This review focuses on the role of AVP in the regulation of stress responsiveness of the HPA axis with emphasis on the effects of aging on vasopressinergic regulation of HPA axis stress responsiveness. Under most of the known stressors, AVP is necessary for acute ACTH secretion but in a context-specific manner. The current data on the AVP role in regulation of HPA responsiveness to chronic stress in adulthood are rather contradictory. The importance of the vasopressinergic regulation of the HPA stress responsiveness is greatest during fetal development, in neonatal period, and in the lactating adult. Aging associated with increased variability in several parameters of HPA function including basal state, responsiveness to stressors, and special testing. Reports on the possible role of the AVP/V1b receptor system in the increase of HPA axis hyperactivity with aging are contradictory and requires further research. Many contradictory results may be due to age and species differences in the HPA function of rodents and primates.

Menopause, A Biocultural Perspective

Each menopausal body is the product of decades of physiological responses to an environment composed of cultural and biological factors. Anthropologists have documented population differences in reproductive endocrinology and developmental trajectories, and ethnic differences in hormones and symptoms at menopause demonstrate that this stage of life history is not exempt from this pattern. Antagonistic pleiotropy, in the form of constraints on the reproductive system, may explain the phenomenon of menopause in humans, optimizing the hormonal environment for reproduction earlier in the life course. Some menopausal symptoms may be side effects of modernizing lifestyle changes, representing discordance between our current lifestyles and genetic heritage. Further exploration of women's experience of menopause, as opposed to researcher-imposed definitions; macro- and microenvironmental factors, including diet and intestinal ecology; and folk etiologies involving the autonomic nervous system may lead to a deeper understanding of the complex biocultural mechanisms of menopause.

Quercetin-6-C-β-D-glucopyranoside isolated from Ulmus wallichiana planchon is more potent than quercetin in inhibiting osteoclastogenesis and mitigating ovariectomy-induced bone loss in rats

OBJECTIVE

The aim of this study was to determine the skeletal effect of quercetin-6-C-β-D-glucopyranoside (QCG) isolated from the extract of Ulmus wallichiana and compare this effect with quercetin (Q) in a rat model of postmenopausal bone loss.

METHODS

Murine bone marrow cells were used to study the effect of QCG or Q on osteoclast differentiation. QCG or Q (1.0 and 5.0 mg kg(-1) d(-1) doses) was administered orally to ovarietomized (OVx) rats for 12 weeks. Sham-operated + vehicle and OVx + vehicle groups served as positive and negative controls, respectively. Bone mineral density, bone microarchitecture, biomechanical strength, bone turnover markers, and uterotrophic effect were studied. One-way analysis of variance was used to test significance of effects.

RESULTS

QCG at 1.0 nM significantly inhibited differentiation of multinucleated osteoclasts and expression of osteoclastogenic genes from bone marrow cells, whereas Q at 10.0 μM had comparable results. OVx rats treated with QCG exhibited significantly higher bone mass and better microarchitecture in trabecular and cortical bones compared with OVx + vehicle. QCG treatment of OVx rats had better functional impact than did Q-treated OVx rats, evident from increased bone biomechanical strength. Serum osteocalcin and urinary fragments of type 1 collagen were significantly lower in QCG-treated OVx rats compared with OVx + vehicle group. The protective effect of QCG under ovariectomy-induced bone loss setting was found to be significantly better than Q. Uterine histomorphometry parameters of OVx rats did not change with QCG treatment.

CONCLUSIONS

QCG improves bone biomechanical quality more effectively than Q through positive modifications of bone mineral density and bone microarchitecture without a hyperplastic effect on the uterus.

Phytoestrogens in postmenopausal indications: A theoretical perspective

This review discusses plant-derived compounds with estrogenic activity. The authors rightly emphasize the need for the intake of foods containing phytoestrogens in view of their positive effects on postmenopausal indications. This is particularly significant in the light of the current wave of enthusiasm for vegetarian food, in general, and phytoestrogens, in particular. Phytoestrogens are plant-derived hormone-like diphenolic compounds of dietary origin. These compounds are weakly estrogenic and could play a role in the prevention of other estrogen-related conditions, namely, cardiovascular diseases, menopausal symptoms, postmenopausal osteoporosis, neuroprotective effects, and hormone-dependent cancers (breast and endometrium cancer).

Prevalence of natural health product use in healthy postmenopausal women

OBJECTIVES

Population studies examining dietary supplement use reveal that users are more likely to be women of older age, yet there are few focused studies among postmenopausal women. The purpose of this study was to determine the prevalence of natural health product (NHP) use, as well as the attitudes and motivations associated with NHP use, among postmenopausal women.

DESIGN

Healthy postmenopausal women were recruited from shopping malls and community centers to complete a questionnaire that collected information regarding use of NHPs; attitudes and motivations about NHPs; and demographic, health, and lifestyle characteristics.

RESULTS

The prevalence of NHP use among the 204 subjects was 83.3%. There were no significant differences in characteristics between NHP users and non-users, with the exception of a lower body mass index among NHP users (P = 0.01). The most commonly consumed NHP was calcium, followed by multivitamins/minerals, vitamin C, and vitamin E. Almost all NHP users (98.8%) believed that NHPs improved their overall health, and most (70.6%) attributed specific positive effects to their NHPs. Three quarters of NHP users believed that their NHPs could not cause adverse effects, and 64.2% believed that their NHPs could not interact negatively with medications. The most common source of NHP information was magazines/books, and 71.8% of NHP users indicated they did not need further information about their NHPs.

CONCLUSIONS

In this study, we found that the prevalence of NHP use among a sample of 204 healthy postmenopausal women was 83.3% and that, apart from body mass index, there were no variables that predicted NHP use.

Diminished aromatase immunoreactivity in the hypothalamus, but not in the basal forebrain nuclei in Alzheimer's disease

In previous studies we have shown in Alzheimer's disease (AD) an enhanced nuclear estrogen receptor (ER) alpha expression in the cholinergic basal forebrain nuclei, i.e. the vertical limb of the diagonal band of Broca (VDB) and the nucleus basalis of Meynert (NBM), and in a number of hypothalamic nuclei, i.e. the supraoptic nucleus (SON), the infundibular nucleus (INF), the medial mamillary nucleus (MMN). We aimed at determining whether the increase in nuclear ERalpha seen in AD patients was related to a rise in local production of estrogens by aromatase (P-450arom), which is a key enzyme that catalyzes the biosynthesis of estrogens from precursor aromatizable androgens. We confirmed for the first time the presence of aromatase mRNA in neurons and glial cells in the human NBM and the tuberomamillary nucleus by RT-QPCR using laser microdissection. Enhanced aromatase immunoreactivity (ir) was indeed observed in the NBM in AD. However, in contrast a decreased aromatase-ir was found in the SON, INF and MMN of AD patients. In addition, P-450arom-ir was clearly diminished in ependymal and choroid plexus cells in AD. While an increase in aromatase-ir was found in the NBM and SON during normal aging, a decrease in staining was observed in the MMN. No sex differences in young control, elderly control or AD patients were present in any of the nuclei studied. In conclusion, brain P-450arom-ir and the relationship of its regulation with plasma sex steroid levels, estrogen and androgen receptors in the human hypothalamus and basal forebrain are region-specific.

Estrogen receptors and metabolic activity in the human tuberomamillary nucleus: changes in relation to sex, aging and Alzheimer’s disease

The human tuberomamillary nucleus (TMN), that is the sole source of histamine in the brain, is involved in arousal, learning and memory and is impaired in Alzheimer's disease (AD) as shown by the presence of cytoskeletal alterations, a reduction in the number of large neurons, a diminished neuronal metabolic activity and decreased histamine levels in the hypothalamus and cortex. Experimental data and the presence of sex hormone receptors suggest an important role of sex steroids in the regulation of the function of TMN neurons. Therefore, we investigated sex-, age- and Alzheimer-related changes in estrogen receptor alpha and beta (ERalpha and ERbeta) in the TMN. In addition, metabolic activity changes of TMN neurons were determined by measuring Golgi apparatus (GA) and cell size. In the present study, ERalpha immunocytochemical expression in AD patients did not differ from that in elderly controls. However, a larger amount of cytoplasmic ERbeta was found in the TMN cells of AD patients. Earlier studies, using the GA size as a parameter, have shown a clearly decreased metabolic activity in the TMN neurons in AD. In the present study, the size of the GA did not change during aging, indicating the absence of strong metabolic changes. Cell size of the TMN neurons appeared to increase during normal aging in men but not in women. Concluding, the enhanced cytoplasmic expression of ERbeta in the TMN may be involved in the diminished neuronal metabolism of these neurons in AD patients.

Changes in metabolic activity and estrogen receptors in the human medial mamillary nucleus: relation to sex, aging and Alzheimer's disease

The medial mamillary nucleus (MMN) is situated caudally in the human hypothalamus and is involved in memory processes. In search for putative sites of action in estrogen replacement therapy on memory both in aging and Alzheimer's disease (AD), we aimed at determining whether changes would occur in estrogen receptors (ER) or metabolic activity in the MMN neurons under these conditions in a sex-dependent way. The Golgi apparatus (GA) and cell size, that were previously shown to be good measures of changes in neuronal metabolic activity, were measured in the MMN of 10 young (20-50 years old), 11 elderly (56-76 years old) control men and women and 11 AD patients (54-78 years old). In addition, we investigated whether estrogen receptor alpha or beta (ERalpha or ERbeta) immunoreactivity was altered in the MMN in aging or AD. There were no sex- or AD-related differences in the GA or cell size in the MMN. Both the GA and cell size of the MMN neurons were found to be increased in postmenopausal compared to young control women accompanied by a decrease in the amount of nuclear ERbeta. The percentage of nuclear ERalpha-positive MMN neurons was markedly enhanced in AD patients compared to controls and most prominently in AD men. In AD patients the proportion of nuclear ERalpha-positive neurons was positively correlated to the Braak stages that indicate the progression of the disease. No differences in the proportion of ERbeta-positive neurons were observed between AD and control patients. We propose that estrogens play an inhibitory role with respect to the metabolic activity of human MMN, which is mediated via ERbeta. This inhibitory effect is diminished in postmenopausal women. The role of the enhanced nuclear ERalpha staining in AD, that was also found in other brain areas, remains to be elucidated.

Increased neuronal metabolic activity and estrogen receptors in the vertical limb of the diagonal band of Broca in Alzheimer's disease: relation to sex and aging

Changes in the interaction between sex hormones and the cholinergic system are presumed to play a role in cognitive decline in aging and Alzheimer's disease (AD). The hippocampus is one of the most strongly affected brain structures in AD and the vertical limb of the diagonal band of Broca (VDB) is its major source of innervation. In the present study we found, surprisingly, for the first time that the neuronal metabolic activity as measured by the size of the Golgi apparatus in the VDB gradually increases after the age of 50 years in controls and that this process starts earlier and is more pronounced in Alzheimer's disease patients. Neuronal metabolic activity in the VDB was significantly higher in AD than in control patients younger than 70 years of age and was higher in control patients over 70 years than in control patients younger than 70 years of age. The activation of VDB neurons during aging was accompanied by an increased nuclear estrogen receptor (ER) beta staining, which was stronger in patients over 70 years of age than in younger subjects (in both controls and AD patients). Interestingly, as in the nucleus basalis of Meynert, nuclear ERalpha expression was markedly enhanced in AD patients compared to controls independent of age. In addition, evidence was found for the influence of APOE genotype on ERalpha and ERbeta staining in the human VDB in aging and in AD. APOE genotype was positively correlated (epsilon 2 < epsilon 3 < epsilon 4) with the percentage of cytoplasm ERalpha-positive VDB neurons in elderly control male and female subjects and with both nuclear and cytoplasm ERbeta-positive neurons in control women. In conclusion, the VDB is compensatory activated and shows more nuclear ER expression in aging and AD in a sex- and APOE genotype-dependent way. So neither global degeneration or a strongly decreased neuronal metabolism nor a lack of sex hormone receptors in the VDB seems to contribute to the decline in cognition in aging or AD in which the hippocampus plays such a crucial role.

Neurohypophyseal peptides in aging and Alzheimer's disease

The neurohypophyseal hormones arginine-vasopressin (AVP) and oxytocin (OT) are produced in the neurons of the hypothalamic supraoptic (SON) and paraventricular (PVN) nucleus and in the much smaller cells of the suprachiasmatic (SCN) nucleus. The SON is the main source of plasma AVP. Part of the AVP and OT neurons of the PVN join the hypothalamo-neurohypophyseal tract, whereas others send projections to the median eminence or various brain areas, where AVP and OT are involved in a number of central functions as neurotransmitters/neuromodulators. AVP and OT from the PVN can also regulate via the autonomous innervation endocrine glands and fat tissue. OT is produced for a major part in the PVN but some OT neurons are present in the SON. Moreover, both AVP and OT containing neurons are observed in the "accessory nuclei", i.e. islands situated between the SON and PVN. The SCN is the biological clock, and the number of AVP expressing neurons in the SCN shows both diurnal and seasonal rhythms. In addition to these hypothalamic areas, AVP and OT may be found to a lesser extent in some other brain areas, such as the bed nucleus of the stria terminalis, diagonal band of Broca, nucleus basalis of Meynert, lateral septal nucleus, globus pallidus and the anterior amygdaloid nucleus, as well as in the peripheral tissues. The AVP and OT containing neurons should not be considered as one system. Prominent functional differences exist between the different nuclei. The heterogeneity also becomes clear from the marked differences in the neurohypophyseal peptides containing neurons of the SON, PVN and SCN during aging, and in the most prevalent age-related neurodegenerative diseases, i.e. Alzheimer's disease (AD). For those reasons, we will discuss the SON, PVN and SCN separately.

Increased expression of estrogen receptor α and β in the nucleus basalis of Meynert in Alzheimer’s disease

The human nucleus basalis of Meynert (NBM) is severely affected in Alzheimer's disease (AD). Since estrogens may reduce both the risk and severity of AD, possibly by an action on the cholinergic system, we determined whether estrogen receptors are present in the human NBM and what their changes are in normal aging and in AD. ERalpha was expressed to a higher degree than ERbeta and was localized mainly in the cell nucleus, while ERbeta was mainly confined to the cytoplasm. A significant positive correlation between the percentage of ERalpha nuclear positive neurons and age was found in men but not in women, whereas the proportion of ERbeta cytoplasm positive cells increased during aging in both sexes. In AD the proportion of neurons showing nuclear staining for both ERalpha and beta and cytoplasmic staining for ERbeta was markedly increased. The percentage of ERbeta nuclear positive neurons increased in AD only in women but not in men. The ApoE genotype had no effect on ER expression in the NBM in AD. In conclusion, whereas only minor sex- and age-related changes in both ERs were found in the human NBM, a clear upregulation of ERalpha and beta was observed in AD.

Metabolic activity of the human ventromedial nucleus neurons in relation to sex and ageing

The ventromedial nucleus (VMN) in animals is involved in a number of sexually dimorphic behaviors, including reproduction, and is a well-documented target for sex steroids. In rats and in lizards, it is also characterized by the presence of structural sexual dimorphisms. In the present study, we determined whether the metabolic activity of human ventromedial nucleus neurons was sex- or age-related. The size of the immunocytochemically defined Golgi apparatus (GA) and cell profiles were determined as measures for neuronal metabolic activity in 12 male and 16 female control brains sub-divided into four groups with the dividing line being the age of 50. It appeared that the size of the GA relative to cell size was 34% larger in young women (<50 years old) than in young men and was 25% larger in elderly men (> or = 50 years old) than in young men. In addition, the GA/cell size ratio correlated significantly with age in men and not in women. Our data suggest that androgens play an inhibitory role with respect to the metabolic activity of the human VMN neurons.

Different associations of blood pressure with 24-hour urinary sodium excretion among pre- and post-menopausal women. WHO Cardiovascular Diseases and Alimentary Comparison (WHO-CARDIAC) Study

OBJECTIVE

Having found no definite relationship between blood pressure (BP) and 24h sodium excretion in women aged 48-56 years (in contrast to the results in men of the same age) in the WHO Cardiovascular Diseases and Alimentary Comparison (WHO-CARDIAC) Study, we analyzed the data to investigate whether the sodium-BP association differed between pre- and post-menopausal women.

DESIGN AND METHODS

The WHO-CARDIAC is a multicenter cross-sectional study, involving, as of July 2000, 60 collaborating centers in 25 countries. In each center, 100 men and 100 women aged 48-56 years were selected randomly from the general population of the area. In this report, 2,212 women in 21 centers located in 17 countries worldwide, who had data on menopausal status, were studied.

RESULTS

After adjustment for age, body mass index (BMI) and 24h urinary potassium excretion, 24h sodium excretion was positively and significantly associated with systolic blood pressure (SBP) [pooled regression coefficient: 0.037 (SE 0.01), P < 0.01] and with diastolic blood pressure (DBP) [0.023 (0.006), P< 0.01] in post-menopausal women. Pooled regression coefficients of sodium-BP association were not significant in pre-menopausal women (P< 0.05). Cross-center correlation analyses of the 21 centers showed that 24h sodium excretion was positively associated with SBP and DBP in both pre- and post-menopausal women, and this positive association between sodium excretion and SBP was significant in post-menopausal women (R2 = 0.23, P = 0.029).

CONCLUSION

Different associations between sodium and BP were observed in women with pre- and post-menopausal status. There may be a tendency for salt sensitivity to increase at the menopause.

Effects of estradiol with and without testosterone on body composition and relationships with lipids in postmenopausal women

OBJECTIVE

The cardioprotective effects of postmenopausal estrogen replacement therapy are mediated by several mechanisms, including favorable effects on lipids and lipoproteins. The extent to which the latter reflects modification of body fat distribution by sex steroids is not known. Hence, we investigated the relationships between changes in lipids and measures of body composition in postmenopausal women who were administered estrogen therapy with and without testosterone.

DESIGN

We randomized 33 postmenopausal women to treatment with either estradiol 50 mg (E) alone or estradiol 50 mg plus testosterone 50 mg implants (E&T) administered every 3 months for 2 years in conjunction with cyclic oral progestins for women with an intact uterus.

RESULTS

Both therapies were associated with sustained reductions in total cholesterol and low-density lipoprotein (LDL) cholesterol. In women who received E but not E&T, hip (p < 0.001) and abdominal circumferences (p < 0.05) and fat mass:fat-free mass (FM:FFM) ratio over the abdomen (p < 0.05) declined. E&T but not E resulted in increased FFM (p < 0.001) and a reduced FM:FFM ratio (p < 0.05). For E but not E&T, the decrease in LDL cholesterol was significantly related to changes in total and compartmental body fat and to change in the FM:FFM ratio (p < 0.05).

CONCLUSION

Estrogen replacement has effects on body fat distribution in postmenopausal women that are associated with improved lipid parameters. Addition ofparenteral testosterone does not negate the favorable effects of estrogen on LDL cholesterol levels but may attenuate the reduction in centralized body fat achieved with E implants.

Differential expression of estrogen receptor alpha and beta immunoreactivity in the human supraoptic nucleus in relation to sex and aging

The dorsolateral supraoptic nucleus (dl-SON) is the main production site of plasma arginine vasopressin (AVP). Plasma AVP levels and the activity of AVP neurons in humans are higher in males than in premenopausal females. On the other hand, an increased activity of AVP neurons becomes prominent in postmenopausal women who have strongly decreased estrogen levels. As estrogens are presumed to inhibit AVP production in a receptor-mediated way, we studied estrogen receptor (ER) alpha and beta immunoreactivity in the dl-SON. Hypothalami of 34 controls were subdivided into 4 groups within a 50-yr boundary (young men, young women, elderly men, and elderly women). The AVP part of the dl-SON of young women contained 50 times more neurons with ERbeta nuclear staining than that in young men and 250 times more than that in elderly women. In addition, young women also showed more ERbeta cytoplasmic staining than young men and elderly women. In contrast to the ERbeta immunoreactivity, no differences were found in the number of ERalpha-positive neurons in the 4 groups, but the age and sex pattern of ERalpha staining was basically opposite that of ERbeta. Significant correlations between the percentage of ERbeta- and ERalpha-positive and -negative AVP neurons and age were found in women, but not in men. Our data demonstrate for the first time a strong decrease of ERbeta and an increase of ERalpha immunoreactivity in AVP neurons of the dl-SON of postmenopausal women. Both receptor changes are proposed to participate in the activation of the AVP neurons in postmenopausal women.

Hormone replacement therapy and 24-hour blood pressure profile of postmenopausal women

Menopause is associated with an increase in blood pressure (BP) and a decrease in physiologic nocturnal BP fall. These factors may play a role in the increased risk of cardiovascular events after menopause. Some studies indicate that transdermal estrogen replacement therapy may help restore the 24-h BP profile, but data on the effect of oral conjugated estrogens are lacking. We compared 24-h ambulatory BP profiles of 42 postmenopausal women not receiving hormone replacement therapy (HRT) and 20 women receiving HRT. HRT was associated with a significant increase in the proportion of dippers (50% in women not receiving HRT and 80% in women receiving HRT, P = .048). Increase in nocturnal dipping may account, in part, for the beneficial cardiovascular effects of HRT.

Serum vascular endothelial growth factor concentrations in postmenopausal women: the effect of hormone replacement therapy

OBJECTIVE

To assess serum vascular endothelial growth factor (VEGF) concentrations in healthy postmenopausal women in relation to hormone replacement therapy (HRT) and the presence or absence of a uterus.

DESIGN

Cross-sectional study.

SETTING

The Middlesex Hospital.

PATIENT(S)

A total of 199 postmenopausal women were enrolled: 132 had uterus in situ and 67 had had hysterectomies. Of the 67 women who had had hysterectomies, 6 received no HRT, 20 received tibolone, 25 received transdermal E2, and 16 received conjugated equine estrogens. Of the 132 women with uteri in situ, 34 received no HRT, 56 received tibolone, 24 received transdermal E2 with sequential norethisterone acetate, and 18 received conjugated equine estrogens with sequential levonorgestrel.

INTERVENTION(S)

Serum VEGF level measurement.

MAIN OUTCOME MEASURE(S)

Serum VEGF concentrations.

RESULT(S)

Women who received HRT had higher VEGF concentrations than those not receiving HRT. Among women who received no HRT, those with uterus in situ had higher VEGF levels than did those who had had hysterectomies. Among women who had had hysterectomies, VEGF concentrations were higher in those who received conjugated equine estrogens than in those who did not receive HRT and those who received tibolone or transdermal E2. Among women with uterus in situ, no difference was found between subgroups.

CONCLUSION(S)

Postmenopausal women with uterus in situ and those who received HRT had higher VEGF concentrations than did those who had had hysterectomies and who did not receive HRT. Among women receiving HRT, those who received conjugated equine estrogens alone had higher VEGF concentrations. This estrogen-mediated increase in serum VEGF concentrations may be a mechanism by which HRT benefits the cardiovascular system.

P75 neurotrophin receptor in the nucleus basalis of meynert in relation to age, sex, and Alzheimer's disease

In a previous study we showed that the staining of tyrosine kinase receptors (trks), which are high-affinity neurotrophin receptors (NTRs), is strongly diminished in the nucleus basalis of Meynert (NBM) of Alzheimer's disease (AD) patients, which may explain the lack of effect of NGF therapy in AD patients so far. Since the literature regarding the expression of low-affinity NTRs was rather controversial, the aim of the present study was to examine (i) possible changes in the staining of low-affinity NTRs, i.e., p75 in the human NBM, an area that is severely affected in AD; and (ii) alterations of these receptors in relation to risk factors for AD, e. g., age, sex, and menopause. Brain material of 31 controls and 30 AD patients was obtained at autopsy, embedded in paraffin, and stained immunocytochemically. Using an image analysis system, we quantified p75 immunoreactivity in both cell bodies and fibers at the level of the NBM. Our results showed a significant diminishment of p75 immunoreactivity in both cell bodies and fibers of NBM neurons in AD. We did not find any relationship between age or sex and the expression of p75 receptor in cell bodies. However, there was a clearly positive relationship between age and fiber staining in AD patients which suggests the occurrence of a p75 transport disorder as an early event in the process of AD. These observations and the earlier reported decreased staining of trk receptors show that degeneration of NBM neurons in AD is associated with a decreased neurotrophin responsiveness of NBM neurons in AD and that therapeutic strategies should be directed toward upregulation of receptors or facilitation of transport before an effect of neurotrophins in AD may be expected.

Aortic plaque size and endometrial response in cholesterol-fed rabbits treated with estrogen plus continuous or sequential progestin

ERT is associated with a reduced incidence of coronary risk and cardiac events in postmenopausal women, but increases the risk of endometrial hyperplasia and carcinoma. Combined estrogen and progestin therapy protects the endometrium; however, its effects on heart disease risk factors are not completely known. In our study, 56 ovariectomized New Zealand White rabbits in 7 groups received a 0.5% cholesterol diet for 12 weeks. Controls were not treated with hormones. All other animals received (per kilogram body weight per week) intramuscular injections of either 0.3 mg estrogen (estradiol valerate) alone, 8.3 mg progestin (hydroxyprogesterone caproate) alone, estrogen and progestin continuously in 3 different dosages (0.3 and 8.3 mg; 1 and 8.3 mg; or 1 and 2.8 mg; estrogen and progestin, respectively), or 1 mg estrogen with 25 mg progestin sequentially in 2-week cycles. Eight non-ovariectomized animals served as further controls for endometrial analysis. Morphometric analysis of plaque size in the aortic arch showed that estrogen monotherapy, and the 3 combined therapies with 1 mg estrogen, significantly reduced intimal thickening (P<0.05). The application of progestin alone had no effect on plaque size. The endometrium was enlarged by 3-fold after estrogen treatment, and was decreased by half after progestin treatment, compared with control uteri (P<0.05). In all groups with combined hormone regimens, endometrial size was not significantly different from control uteri. However, these uteri showed more inflammatory reactions, especially when higher doses of hormones were given. In this animal model, doses of progestin that are able to successfully reduce the proliferative effect of estrogen on endometrium do not diminish the desirable antiatherosclerotic properties of estrogen.

A mouse model to study the effects of hormone replacement therapy on normal mammary gland during menopause: enhanced proliferative response to estrogen in late postmenopausal mice

Hormone replacement therapy (HRT) with estrogen alleviates menopausal symptoms and is effective in reducing osteoporosis and cardiovascular disease when taken in early postmenopause. Older, late postmenopausal women who never previously received HRT are also believed to benefit from estrogen treatment. On the other hand, increased lifetime exposure of the mammary gland to estrogen may increase the risk of breast cancer. The development of suitable experimental animal model systems can advance our understanding of the effects of estrogen and the timing of HRT on the postmenopausal breast. Toward this end, early and late postmenopausal states were induced in mice by short vs. long term ovariectomy (1 vs. 5 weeks), and the effects of 17beta-estradiol (E) on mammary gland morphology, cell proliferation, and progesterone receptor (PR) levels were investigated. We report that in late postmenopausal mice, E caused a pronounced enlargement of duct ends and 6.5- and 4-fold greater mitogenic responses in the duct end epithelium and adjacent stromal cells, respectively, compared with the response in early postmenopausal mice. Furthermore, after long term, daily treatment with E, steady state levels of proliferation remained 2-fold higher than those of similarly treated, early postmenopausal mice. E failed to increase mammary PR levels in late postmenopausal, but not in early postmenopausal mice. Stimulation of duct ends by E and lack of PR inducibility are characteristics of the immature pubertal mammary gland and indicate that the late postmenopausal mammary gland resembled the immature state. In contrast, minimal E-induced proliferation and increased PR inducibility, characteristics of the adult, sexually mature mammary gland, were retained in early postmenopausal mice. The lack of difference in the numbers of estrogen receptor-positive epithelial or stromal cells or in estrogen receptor cellular concentration after short vs. long term ovariectomy indicates that the observed greater efficacy of E is mediated at a step beyond receptor-ligand binding. This mouse model of experimentally induced early vs. late postmenopausal states should prove useful in better understanding alterations in hormone responsiveness and their implications for timing of HRT on the human breast.

Activity of vasopressinergic neurones of the human supraoptic nucleus is age- and sex-dependent

In the human hypothalamus, arginine-vasopressin (AVP) is produced for a major part by the neurones of the supraoptic nucleus (SON). Since plasma AVP levels in men were reported to be higher than those of women and we did not find a sex difference in the neurone number, a higher vasopressinergic neurone activity was supposed to be present in the SON of men. Therefore we studied the size of the Golgi-apparatus (GA), which has been demonstrated previously to be a sensitive parameter for protein synthetic ability of neurones, in 15 men and 17 women ranging in age from 29 to 94 years. A polyclonal antibody against immunoaffinity purified MG-160, a sialoglycoprotein of the medial cisternae of the GA was applied on paraffin-embedded sections containing the dorsolateral SON (dl-SON) from which 90-95% of neurones are vasopressinergic. SON areas that contain oxytocin (OT) cells were excluded on the basis of adjacent sections stained with a monoclonal antibody against OT. By means of an image analysis system the size of the GA and the cellular profile area were determined in dl-SON neurones with a nucleolus. Our results showed indeed an age-dependent sex difference in the size of the GA that appeared to be twice as large in young men (< or = 50 years old) than in young women of the same age. The size of the GA increased with age in women but not in men. In addition, the mean cell profile area, another measure for neuronal activity, was significantly larger in young men than in young women and was in old women larger than in young women. In conclusion, these data show the presence of a sex-dependent age-difference in the activity of vasopressinergic neurones in dl-SON which may relate to differences in AVP and sex hormone levels and kidney AVP receptors.