Differences in vascular reactivity between men and women

The purpose of this study was to compare the gender and age-related differences in vascular reactivity in healthy men and women across a wide age range. Fifty-seven men and 61 women between 20 and 89 years of age, free of cardiovascular disease and risk factors, were categorized into younger (20-39 years), middle-aged (40-59 years), and older (60-89 years) age groups. Subjects were characterized on body weight and height, body mass index (BMI), and calf blood flow under resting, postocclusive reactive hyperemic (PORH), and maximal hyperemic conditions in the lower extremity with use of venous occlusion mercury strain-gauge plethysmography. Similar baseline characteristics were observed among age groups, whereas men had greater body weight (p<0.05), higher BMI values (p<0.05), and a trend toward higher ankle-brachial index (ABI) values (p=0.054) than women. While calf blood flow measurements were similar for men and women at rest and at maximal hyperemic conditions, women had a greater percentage change in calf blood flow from rest to PORH than men (p=0.046). After adjusting for body weight, BMI, and ABI, the percentage change in calf blood flow from rest to PORH was no longer significantly higher in the women (p>0.05). Furthermore, the percentage change in calf blood flow from rest to PORH was negatively related to body weight (r = -0.30, p<0.01) and to BMI (r = -0.26, p<0.01) in the men and women. No differences (p>0.05) in the calf blood flow measures were observed among the age groups. In a healthy cohort free of cardiovascular disease, increased BMI accounted for poorer vascular reactivity in men compared to women regardless of age.     

Isoflavones from red clover improve systemic arterial compliance but not plasma lipids in menopausal women

The possibility that the heightened cardiovascular risk associated with the menopause can be reduced by increasing dietary isoflavone intake was tested in 17 women by measuring arterial compliance, an index of the elasticity of large arteries such as the thoracic aorta. Compliance diminishes with age and menopause. An initial 3- to 4-week run-in period and a 5-week placebo period were followed by two 5-week periods of active treatment with 40 mg and then 80 mg isoflavones derived from red clover containing genistein, daidzein, biochanin, and formononetin in 14 and 13 women, respectively, with 3 others serving as placebo controls throughout. Arterial compliance, measured by ultrasound as a pressure (carotid artery) and volume (outflow into aorta) relationship, was determined after each period; plasma lipids were measured twice during each period. Urinary output of isoflavones was also determined. Arterial compliance rose by 23% relative to that during the placebo period with the 80-mg isoflavone dose and slightly less with the 40-mg dose (mean +/- SEM: placebo, .197 +/- .015; 40 mg, .237 +/- 0.007; 80 mg, .244 +/- .014). In the three women receiving continuous placebo, compliance was .16 +/- .022, similar to that during the run-in period for the remaining subjects (.17 +/- .021) [corrected]. ANOVA showed a significant (P = < 0.001) difference between treatments; by Bonferroni multiple comparisons and by paired t test, differences were significant between placebo and 40- and 80-mg isoflavone doses (by paired t test: P = 0.039 for placebo vs. 40 mg; P = 0.018 for placebo vs. 80 mg). Plasma lipids were not significantly affected. An important cardiovascular risk factor, arterial compliance, which diminishes with menopause, was significantly improved with red clover isoflavones. As diminished compliance leads to systolic hypertension and may increase left ventricular work, the findings indicate a potential new therapeutic approach for improved cardiovascular function after menopause.     

铁调素治疗围绝经期和绝经后骨质疏松症

目前采用激素替代疗法治疗绝经后骨质疏松症仅部分有效.近年的研究发现,绝经后骨质疏松症的发生除与雌激素缺乏有关外,还可能与铁过载有关.铁调素是一种肽类激素,主要调节体内铁的平衡.铁调素可以有效抑制肠道对铁的吸收,降低铁水平,因而具有预防和治疗围绝经期和绝经后女性骨质疏松症的潜在价值.     

Characterization of inhibin immunoreactivity in post-menopausal women with ovarian tumours

BACKGROUND AND OBJECTIVE We have previously reported elevated serum immunoreactive inhibin (INH) levels in patients with ovarian malignancies, particularly granulosa cell and mucinous tumours. The present study was designed to compare INH measurements using a heterologous radioimmunoassay with cross-reactivity for inhibin α-subunit derived peptides with measurements obtained using a new ELISA specific for dimeric inhibin-A. It was hypothesized that granulosa cell tumours may secrete significant quantities of inhibin-A whereas mucinous tumours were unlikely to do so because of the lack of a relation between INH and FSH measurements in the latter group. DESIGN Serum samples obtained from women found to have ovarian cancer were assayed using the heterologous radioimmunoassay (the Monash assay) and using an ELISA specific for dimeric inhibin (the Groome assay) and the results were compared. PATIENTS Samples for assay were available from 69 normal post-menopausal control women, 12 patients with mucinous tumours of the ovary, 26 with serous tumours, 7 with granulosa cell tumours and 8 with various other ovarian tumours. Patients were post-menopausal or had been subjected to bilateral oophorectomy at the time these samples were collected. MEASUREMENTS The Monash and Groome assays were carried out as described previously. The upper limit of normal for post-menopausal women in the Monash assay was 122 U/l and for the Groome assay was calculated to be 32 ng/l. RESULTS Among the 69 normal subjects, 4 were found to have elevated inhibin levels using the Monash RIA (133–190 U/l) and 4 were found to have elevated levels in the Groome ELISA (45.5–55.3 ng/l). Among 12 patients with mucinous tumours, 10 (83%) had elevated inhibin levels using the Monash assay but only 3 (25%) had elevated levels with the Groome assay (P < 0.005). Among 26 with serous tumours, 15 (58%) had elevated levels in the Monash assay but only 1 (4%) in the Groome assay (P < 0.001). Among 7 samples from patients with granulosa cell tumours, 100% were elevated in the Monash assay and 71% in the Groome assay (NS, non-significant). In a miscellaneous group of tumours all 8 had elevated levels in the Monash assay and 2 in the Groome assay (P < 0.001). CONCLUSIONS It was concluded that in normal post-menopausal subjects, INH is generally undetectable or present at low levels, consistent with the loss of ovarian function. The majority of granulosa cell tumours appear to secrete significant amounts of dimeric inhibin-A, whereas mucinous tumours secrete predominantly other forms of INH, presumably related to the α-subunit. Serous tumours may also secrete inhibin-related peptides but not dimeric inhibin-A. The nature of the inhibin related peptides produced by epithelial ovarian cancers remains to be characterized.     

Increased asymmetric dimethylarginine and enhanced inflammation are associated with impaired vascular reactivity in women with endometriosis

Objective

Enhanced inflammatory responses which may inhibit vascular reactivity, are associated with endometriosis development. Asymmetric dimethylarginine (ADMA), an inhibitor of endogenous nitric oxide synthase, is also implicated in endothelial dysfunction. We aimed to determine whether plasma ADMA and systemic inflammation are associated with endothelial function in women with endometriosis.

Methods

We evaluated 41 women with and 28 women without endometriosis. Plasma levels of lipids and inflammatory markers such as high sensitive-C reactive protein (hs-CRP), serum amyloid protein A (SAA), and interleukin-6 (IL-6) were measured in the two groups. We also measured levels of ADMA and symmetric dimethylarginine (SDMA). High-resolution ultrasonography measured flow-mediated vasodilation (FMD) to assess vasodilatory responses.

Results

FMD was significantly lower in women with endometriosis compared to those without endometriosis (8.39 ± 0.43% vs 10.79 ± 0.54%, P = 0.001). While plasma lipid levels did not differ significantly between groups, levels of AMDA, but not SDMA, were significantly higher in women with endometriosis (409.7 ± 10.1 pmol/L vs 383.0 ± 48.3 pmol/L, P = 0.04). Inflammatory markers were also significantly higher in these women (hs-CRP: 1053.3 ± 252.0 ng/mL vs 272.0 ± 83.3 ng/mL, P = 0.02; SAA: 8.00 ± 1.53 μg/mL vs 3.82 ± 0.42 μg/mL, P = 0.04; IL-6: 2.73 ± 0.75 pg/mL vs 1.05 ± 0.60 pg/mL, P = 0.04). FMD was negatively correlated with plasma levels of ADMA (r = −0.37, P = 0.01) and log hs-CRP (r = −0.34, P = 0.01).

Conclusion

Increased plasma ADMA levels and enhanced inflammation are associated with inhibited endothelial function in women with endometriosis.     

Decreased retinol transport proteins in Thai post-menopausal women with osteoporosis

High vitamin A ingestion or high serum retinol have been postulated to increase the risk of fractures and osteoporosis by reduced bone mineral density (BMD). Retinol is carried and transported to the tissues bound to retinol binding protein 4 (RBP4) and transthyretin (TTR). The relationships between retinol, retinol transport protein, retinol binding protein 4 (RBP4) and transthyretin (TTR) and BMD and osteoporosis are unclear. To examine the association between retinol and RBP4 and TTR and osteoporosis, 73 osteoporotic and 71 normal Thai postmenopausal women were studied. RBP4 and retinol levels did not differ between the groups. Serum TTR was significantly higher in control than osteoporotic subjects (89.47 and 144.53 microg/ml, respectively, p = 0.003, Mann-Whitney U test). TTR was positively correlated with BMD at several sites, such as the total radius bone (r = 0.172, p = 0.008, Spearman rank test). Osteoporosis risk was analyzed with binary logistic regression. Lean elderly Thais with lower TTR levels had a higher risk of osteoporosis. RBP4 and retinol levels had no relationship with disease status among Thai post-menopausal women. These results suggest calcium, minerals, vitamins and the retinol transport protein, transthyretin may be involved in the pathogenesis of osteoporosis.     

Accelerated bone loss in post-menopausal women with mild primary hyperparathyroidism

OBJECTIVES Osteopenia is regarded as an indication for parathyroidectomy in primary hyperparathyroidism. However, uncertainty exists as to the extent and degree of the skeletal effects in those with mild disease. We sought to determine whether mild primary hyperparathyroidism affects the rate of bone loss in post-menopausal women.
DESIGN Prospective 2-year comparison of rates of bone loss throughout the skeleton in 17 post-menopausal women with untreated mild asymptomatic primary hyperparathyroidism, and 48 age-matched, eucalcaemic controls.
RESULTS The women with primary hyperparathyroidism had a greater annual rate of loss of bone mineral density (BMD) of the total body (mean ± SE, primary hyperparathyroidism −1.15 ± 0.31%, controls −0.39 ± 0.10%; P  = 0.04) and its spine subregion (primary hyperparathyroidism −2.08 ± 0.88%, controls 0.04 ± 0.35%; P  = 0.02). Lumbar spine BMD tended to decline in the primary hyperparathyroidism group (−0.35 ± 0.33%) in contrast to the control group (+ 0.28 ± 0.22%) ( P  = 0.10). There were no significant differences between the groups in rates of change of BMD in the legs or the proximal femur. In the primary hyperparathyroidism group, the rate of total body bone loss in the eight women known at study entry to have had long-standing (>5 years) primary hyperparathyroidism was −1.52 ± 0.61%/year, similar to that of the whole group.
CONCLUSION Primary hyperparathyroidism is associated with an increased rate of loss of total body bone mineral density in post-menopausal women. Prolonged disease duration is therefore likely to be associated with an increasing risk of osteopenia, such that skeletal surveillance and interventions designed to reduce bone loss should be considered.     

Polycystic ovaries in pre and post-menopausal women

OBJECTIVE  Polycystic ovaries have been diagnosed in more than 20% of premenopausal women using ultrasound. The aim of this study was to determine whether polycystic ovaries exist in post-menopausal women.
DESIGN  Two groups of women were studied; group 1 consisted of 18 post-menopausal volunteers and group 2 comprised 142 women, 94 of whom were post-menopausal who had recently undergone coronary angiography.
MEASUREMENTS  Transabdominal and transvaginal ultrasound scans were performed and measurements made of uterine area, endometrial thickness and ovarian volume. The morphological appearance of the ovaries was also noted. Fasting blood samples were taken. Medical and menstrual questionnaires were completed.
RESULTS  Polycystic ovaries were found in 8/18 (44%) of group 1 and 60/142 (42%) in group 2. Polycystic ovaries were detected in 35/94 (37%) of the post-menopausal women in group 2. Post-menopausal women with polycystic ovaries had larger ovaries containing more follicles compared with post-menopausal women with normal ovaries. Post-menopausal women with polycystic ovaries had higher serum concentrations of testosterone and triglycerides than had post-menopausal women with normal ovaries.
CONCLUSIONS  Polycystic ovaries can be detected in post-menopausal women and have some of the same endocrine abnormalities which are evident in premenopausal women with polycystic ovaries, that is, raised serum concentrations of testosterone and triglycerides.     

Body composition and bone mass in post-menopausal women

OBJECTIVE: We aimed to assess total body composition and to study the interrelationships between fat and lean tissue mass with total and regional bone mass in healthy British post-menopausal women. DESIGN AND PATIENTS: Total body composition and regional bone mass were measured in 97 healthy post-menopausal women recruited from the general community. The mean age was 57.9 years, range 49-65. MEASUREMENTS: Total body composition (fat, lean tissue and bone mineral) and regional bone density in the lumbar spine and femur were measured by dual energy X-ray absorptiometry on a Lunar DPX. RESULTS: Significant negative correlations with age were found for total body bone mineral density (r = -0.200, P = 0.049), and lumbar spine bone mineral density (r = -0.28, P = 0.006); the calculated rate of bone loss from these two sites was 0.33 and 0.7% per annum respectively. Fat tissue mass showed a positive correlation with age (r = 0.22, P = 0.03). High correlations were observed between total body and regional bone mineral density (r = 0.755-0.829, P < 0.001). After adjustment for age and lean mass, statistically significant correlations were seen between fat tissue mass and all bone mass measurements (P < 0.01-0.001), the strongest correlations being found for total body bone mineral content and density (r = 0.477 and 0.488 respectively). Lean tissue mass showed a strong correlation with total body bone mineral content (r = 0.580, P < 0.001), after adjustment for age and fat mass; it was less strongly correlated with other bone mass measurements than fat mass, showing only weak correlations with total body, trochanteric and lumbar spine bone mineral density (r = 0.228-0.246, P < 0.05). Age-adjusted body weight showed stronger correlations with total and regional bone mass than did either body mass index or height. CONCLUSIONS: Both fat and lean tissue mass are related to total and regional bone mass in post-menopausal women, the relationship being strongest for fat mass. Body weight shows stronger correlations with bone mass than either height or body mass index. In view of the direction and magnitude of changes in fat, lean tissue and bone mineral after the menopause, adiposity and muscularity are more likely to be determinants of peak bone mass than of the rate of post-menopausal bone loss.     

Prevention of osteoporotic fractures in post-menopausal women.

A number of pharmacological interventions are now available for the prevention of osteoporotic fractures in post-menopausal women. These include hormone replacement therapy, bisphosphonates, raloxifene, calcitonin, calcitriol and combined calcium and vitamin D. Factors influencing the positioning of these agents in clinical practice include their efficacy in preventing fractures at both the spine and the hip, tolerability, side-effects, cost and, in the case of raloxifene and hormone replacement therapy, the extra-skeletal risks and benefits of long-term treatment. The rates of onset and offset of the treatment effect are also important considerations; the observations that relatively short-term intervention produces a significant reduction in fracture risk in women with established osteoporosis, that treatment benefits are greatest in those with low bone mineral density and that the beneficial skeletal effects are not maintained after the withdrawal of treatment have resulted in a shift from long-term preventive strategies towards the targeting of high-risk individuals for intervention.     

绝经后冠心病患者及正常妇女尼尔雌醇替代治疗的观察

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