Association of circulating adiponectin with testosterone in women during the menopausal transition

Associations of LH and FSH with reproductive hormones depending on each stage of the menopausal transition

INTRODUCTION

Associations of luteinizing hormone (LH) with androgens during the menopausal transition and associations between follicle-stimulating hormone (FSH) levels and various diseases related to reproductive hormones in postmenopause have received much attention. LH and FSH are also known to be associated with activities of enzymes related to reproductive hormones. We examined the associations of LH and FSH with androgens and estrogens in each stage of the menopausal transition according to a classification from menopausal transition to postmenopause.

METHODS

This study was a cross-sectional design. We basically used the Stage of Reproductive Aging Workshop (STRAW) + 10. We divided the 173 subjects into 6 groups according to menstrual regularity and follicle-stimulating hormone level: mid reproductive stage (Group A), late reproductive stage (Group B), early menopausal transition (Group C), late menopausal transition (Group D), very early postmenopause (Group E) and early postmenopause (Group F). Levels of LH, FSH, dehydroepiandrosterone sulfate (DHEAS), estradiol, estrone, testosterone (T), free T, androstenedione and androstenediol were measured.

RESULTS

In Group A, LH showed significant positive correlations with androstenedione and estrone. In Group D, LH was positively associated with T and free T and was negatively associated with estradiol. In Groups B, C, D and F, LH showed significant positive correlations with FSH, and there was a tendency for an association between LH and FSH in Group E. FSH was associated with estradiol but not with estrone in Groups C and D.

CONCLUSION

The associations of LH and FSH with reproductive hormones are different depending on the stage of the menopausal transition.

TRIAL REGISTRATION

Trial registration number 2356-1; Date of registration: 18/02/2018, retrospectively registered.

Vascular endothelial adiponectin signaling across the life span

Cardiovascular disease risk increases with age regardless of sex. Some of this risk is attributable to alterations in natural hormones throughout the life span. The quintessential example of this being the dramatic increase in cardiovascular disease following the transition to menopause. Plasma levels of adiponectin, a "cardioprotective" adipokine released primarily by adipose tissue and regulated by hormones, also fluctuate throughout one's life. Plasma adiponectin levels increase with age in both men and women, with higher levels in both pre- and postmenopausal women compared with men. Younger cohorts seem to confer cardioprotective benefits from increased adiponectin levels yet elevated levels in the elderly and those with existing heart disease are associated with poor cardiovascular outcomes. Here, we review the most recent data regarding adiponectin signaling in the vasculature, highlight the differences observed between the sexes, and shed light on the apparent paradox regarding increased cardiovascular disease risk despite rising plasma adiponectin levels over time.

Correlations of androstenediol with reproductive hormones and cortisol according to stages during the menopausal transition in Japanese women

Associations of androstenediol, which has both androgenic and estrogenic activities, with circulating reproductive hormones and stress hormone in women during the menopausal transition may be different depending on the menopausal stage. The aim of this study was to determine the changes in circulating androstenediol during the menopausal transition in Japanese women and the associations of androstenediol with estrogen, androgen and cortisol for each stage of the menopausal transition. We divided the 104 subjects into 6 stages by menstrual regularity and follicle-stimulating hormone level: mid reproductive stage, late reproductive stage, early menopausal transition, late menopausal transition, very early postmenopause and early postmenopause. Levels of dehydroepiandrosterone sulfate (DHEAS), estradiol, estrone, testosterone (T), free T, androstenedione and cortisol were measured. Serum androstenediol concentration was measured by using liquid chromatography mass spectrometry. There were no significant differences in androstenediol levels among the 6 stages. Levels of DHEA-S and testosterone showed significant and positive correlations with androstenediol in all stages. Estradiol levels showed negative correlations with androstenediol levels in the late menopausal transition and very early postmenopause (r=-0.452, p = 0.052 and r=-0.617, p = 0.006, respectively). Cortisol levels showed significant and positive correlations with androstenediol levels in the mid and late reproductive stages (r = 0.719, p = 0.003 and r = 0.808, p < 0.001, respectively).The associations of androstenediol with estradiol and cortisol were different depending on the stage of the menopausal transition. Androstenediol may play a compensatory role for estrogen deficiency from late menopausal transition to very early postmenopause.

Circulating dehydroepiandrosterone-sulphate decreases even with a slight change in oestradiol

The aim of this study was to determine the effect of hormone replacement therapy (HRT) on changes in circulating dehydroepiandrosterone-sulphate (DHEA-S) with focus on the relationship between oestrogen level and change in DHEA-S. Forty-two women were enrolled in this longitudinal study. Nineteen women received oral oestradiol and twenty-three women received transdermal oestradiol continuously. Twenty women received progesterone continuously except for women who had undergone hysterectomy. Circulating oestradiol, follicle-stimulating hormone, luteinising hormone and DHEA-S levels before and at 3 months after commencement of HRT were measured. Circulating DHEA-S level was significantly decreased at 3 months (p < .001). Oestradiol level at 3 months ranged from 6.5 pg/ml to 159 pg/ml. There was no significant correlation of ΔDHEA-S (DHEAS level at 3 months-DHEA-S level at baseline) with Δoestradiol (r = 0.114, p = .471). Circulating DHEA-S level was significantly decreased at 3 months in all the four quartiles and divided according to Δoestradiol, and ΔDHEA-S did not show significant differences. In conclusion, circulating DHEA-S decreases even with a slight increase in oestradiol level. Impact statement What is already known on this subject: A transient increase in DHEA-S in women during the menopausal transition may be involved in the occurrence of menopausal symptoms and/or unfavourable metabolic changes. Hormone replacement therapy decreases circulating DHEA-S level. However, dose dependency of the change in DHEA-S on oestrogen has not been reported. What the results of this study add: Circulating DHEA-S decreases even with a slight increase in oestradiol level. What the implications are of these findings for clinical practice and/or further research: Adrenal function may respond to a small change in oestrogen.

Novel bone metabolism-associated hormones: the importance of the pre-analytical phase for understanding their physiological roles

The endocrine function of bone is now a recognized feature of this tissue. Bone-derived hormones that modulate whole-body homeostasis, are being discovered as for the effects on bone of novel and classic hormones produced by other tissues become known. Often, however, the data regarding these last generation bone-derived or bone-targeting hormones do not give about a clear picture of their physiological roles or concentration ranges. A certain degree of uncertainty could stem from differences in the pre-analytical management of biological samples. The pre-analytical phase comprises a series of decisions and actions (i.e., choice of sample matrix, methods of collection, transportation, treatment and storage) preceding analysis. Errors arising in this phase will inevitably be carried over to the analytical phase where they can reduce the measurement accuracy, ultimately, leading discrepant results. While the pre-analytical phase is all important, in routine laboratory medicine, it is often not given due consideration in research and clinical trials. This is particularly true for novel molecules, such as the hormones regulating the endocrine function of bone. In this review we discuss the importance of the pre-analytical variables affecting the measurement of last generation bone-associated hormones and describe their, often debated and rarely clear physiological roles.

Changes of liver enzymes and triglyceride during the menopausal transition in Japanese women

We examined detailed changes in liver enzymes as surrogate markers for metabolic syndrome and non-alcoholic fatty liver disease (NAFLD) during the menopausal transition and the associations of liver enzymes with lipid profiles related to risk of metabolic syndrome and endocrinological hormones. We divided 393 women into seven stages by menstrual regularity, follicle-stimulating hormone level and years since menopause. Serum levels of alanine aminotranferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase, lipid parameters, glucose, and endocrinological hormones were measured. Both levels of AST and ALT increased towards early post-menopause. AST remained high in late post-menopause but ALT decreased. The AST/ALT ratio decreased towards late menopausal transition and very early post-menopause and increased thereafter. This ratio was negatively correlated with triglyceride. Significant changes in ALT and AST/ALT ratio during the menopausal transition, which were associated with triglyceride, might be involved in the occurrence of metabolic syndrome and NAFLD in Japanese women.

Modulation of Breast Cancer Risk Biomarkers by High-Dose Omega-3 Fatty Acids: Phase II Pilot Study in Postmenopausal Women

Associational studies suggest higher intakes/blood levels of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) relative to the omega-6 arachidonic acid (AA) are associated with reduced breast cancer risk. We performed a pilot study of high-dose EPA + DHA in postmenopausal women to assess feasibility before initiating a phase IIB prevention trial. Postmenopausal women with cytologic evidence of hyperplasia in their baseline random periareolar fine needle aspiration (RPFNA) took 1,860 mg EPA +1500 mg DHA ethyl esters daily for 6 months. Blood and breast tissue were sampled at baseline and study conclusion for exploratory biomarker assessment, with P values uncorrected for multiple comparisons. Feasibility was predefined as 50% uptake, 80% completion, and 70% compliance. Trial uptake by 35 study entrants from 54 eligible women was 65%, with 97% completion and 97% compliance. Favorable modulation was suggested for serum adiponectin (P = 0.0027), TNFα (P = 0.016), HOMA 2B measure of pancreatic β cell function (P = 0.0048), and bioavailable estradiol (P = 0.039). Benign breast tissue Ki-67 (P = 0.036), macrophage chemoattractant protein-1 (P = 0.033), cytomorphology index score (P = 0.014), and percent mammographic density (P = 0.036) were decreased with favorable effects in a proteomics array for several proteins associated with mitogen signaling and cell-cycle arrest; but no obvious overall effect on proteins downstream of mTOR. Although favorable risk biomarker modulation will need to be confirmed in a placebo-controlled trial, we have demonstrated feasibility for development of high-dose EPA and DHA ethyl esters for primary prevention of breast cancer.

Adiposity distribution influences circulating adiponectin levels

Thirty percent of obese individuals are metabolically healthy and were noted to have increased peripheral obesity. Adipose tissue is the primary source of adiponectin, an adipokine with insulin-sensitizing and anti-inflammatory properties. Lower adiponectin levels are observed in individuals with obesity and those at risk for cardiovascular disease. Conversely, higher levels are noted in some obese individuals who are metabolically healthy. Our objective was to determine whether abdominal adiposity distribution, rather than body mass index (BMI) status, influences plasma adiponectin level. A total of 424 subjects (female, 255) of Northern European ancestry were recruited from "Take Off Pounds Sensibly" weight loss club members. Demographics, anthropometrics, and dual-emission x-ray absorptiometry of the whole body, and computed tomography scan of the abdomen were performed to obtain total body fat content and to quantify subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT), respectively. Laboratory measurements included fasting plasma glucose, insulin, lipid panel, and adiponectin. Age- and gender-adjusted correlation analyses showed that adiponectin levels were negatively correlated with BMI, waist circumference, triglycerides, total fat mass, and VAT. A positive correlation was noted with high-density lipoprotein cholesterol and fat-free mass (P < 0.05). SAT-to-VAT ratios were also significantly associated with adiponectin (r = 0.13, P = 0.001). Further, the best positive predictors for plasma adiponectin were found to be SAT-to-VAT ratios and gender by regression analyses (P < 0.01). Abdominal adiposity distribution is an important predictor of plasma adiponectin and obese individuals with higher SAT-to-VAT ratios may have higher adiponectin levels.

Testosterone dose-response relationships with cardiovascular risk markers in androgen-deficient women: a randomized, placebo-controlled trial

OBJECTIVE

To determine dose-dependent effects of T administration on cardiovascular risk markers in women with low T levels.

METHODS

Seventy-one hysterectomized women with or without oophorectomy with total T < 31 ng/dL and/or free T < 3.5 pg/mL received a standardized transdermal estradiol regimen during the 12-week run-in period and were then randomized to receive weekly im injections of placebo or 3-, 6.25-, 12.5-, or 25-mg T enanthate for 24 weeks. Total and free T levels were measured by liquid chromatography-tandem mass spectrometry and equilibrium dialysis, respectively. Insulin resistance and inflammatory markers were measured at baseline and 24 weeks. In a subset of women, magnetic resonance imaging of the abdomen was performed to quantify abdominal fat volume.

RESULTS

Fifty-nine women who completed the 24-week intervention were included in the final analysis. The five groups were similar at baseline. Mean on-treatment nadir total T concentrations were 14, 79, 105, 130, and 232 ng/dL in the placebo group and the 3-, 6.25-, 12.5-, and 25-mg groups, respectively. No significant changes in fasting glucose, fasting insulin, homeostatic model assessment of insulin resistance, high sensitivity C-reactive protein, adiponectin, blood pressure, and heart rate were observed at any T dose when compared to placebo. Similarly, no dose- or concentration-dependent changes were observed in abdominal fat on magnetic resonance imaging.

CONCLUSION

Short-term T administration over a wide range of doses for 24 weeks in women with low T levels was not associated with worsening of cardiovascular risk markers.

Gender differences in adiponectin levels and body composition in older adults: Hallym aging study

Background

Body composition changes with ageing can influence the adiponectin concentration. However, the component of body composition that is associated with adiponectin concentrations in older adults remains unclear.

Methods

There were 152 males and 168 females aged 65 years or older that participated in the 2010 Hallym Aging Study (HAS). Body composition (assessed by dual energy X-ray absorptiometry; DXA), anthropometric parameters and adiponectin were obtained from all participants. Multivariate linear regression models assessed the association of body fat percentage, regional muscle and bone mineral contents of body composition and waist/height ratio with adiponectin concentration. Age, albumin, testosterone concentration and metabolic parameters were considered as confounding factors.

Results

In correlation analysis, age was positively associated with adiponectin in males (P < 0.01), but not in females. Fasting glucose, albumin, arm skeletal muscle mass and bone mineral content were negatively associated with adiponectin in males (P < 0.05). Testosterone and leg bone mineral content were negatively associated with adiponectin in females (P < 0.05). In multivariate linear regression models, body fat percentage and albumin (P < 0.05) were negatively associated with adiponectin, and high-density lipoprotein cholesterol (HDL-C) (P < 0.001) and age (P < 0.01) were positively associated with adiponectin in older males. In older females, the only factors that correlated significantly with adiponectin concentration were the homeostasis model assessment of insulin resistance (P < 0.001) and HDL-C (P < 0.05). The waist/height ratio and bone mineral content were not associated with adiponectin in either gender.

Conclusion

Plasma adiponectin levels correlated negatively with body fat percentage in older males but not in older females. The differential results between older males and females suggest that certain gender-specific mechanisms may affect the association between adiponectin and age-related body composition changes.

Adiponectin as a biomarker of osteoporosis in postmenopausal women: controversies

The literature reports indicating a link between plasma levels of adiponectin and body fat, bone mineral density, sex hormones, and peri- and postmenopausal changes, draw attention to the possible use of adiponectin as an indicator of osteoporotic changes, suggesting that adiponectin may also modulate bone metabolism. In this study, we attempted to analyze the available in vitro and in vivo results which could verify this hypothesis. Although several studies have shown that adiponectin has an adverse effect on bone mass, mainly by intensifying resorption, this peptide has also been demonstrated to increase the proliferation and differentiation of osteoblasts, inhibit the activity of osteoclasts, and reduce bone resorption. There are still many ambiguities; for example, it can be assumed that concentrations of adiponectin in plasma do not satisfactorily reflect its production by adipose tissue, as well as conflicting in vitro and in vivo results. It seems that the potential benefit in the treatment of patients with osteoporosis associated with the pharmacological regulation of adiponectin is controversial.

Adiponectin and waist circumference as predictors of insulin-resistance in women

BACKGROUND AND AIMS

The initial disturbance of insulin resistance seems to focus on adipose tissue is a dynamic organ involved in many physiological and metabolic processes. Expresses and secretes a variety of active peptides, adipocytokines. To evaluate the prevalence of insulin-resistance in an healthy urban middle age population and to explore the role of adiponectin, inflammatory biomarkers (hs-CRP) and traditional cardiovascular risk factors as predictors of the insulin-resistance state.

MATERIALS AND METHODS

We studied of 176 participants (117 women and 59 men, 25-74 years), individuals with diabetes, hypothyroidism or hyperthyroidism, infectious disease, renal, or hepatic neoplasms and pregnant women were excluded. We evaluated glucose, insulin, adiponectin and hs-CRP.

RESULTS

We found that 17.2% of individuals presented insulin-resistance. Correlation was found between waist circumference, body mass index, blood pressure and HOMA index (p<0.01). Adiponectin was associated with the insulin-resistance (p<0.001) but not hs-CRP. Adiponectin (β=0.385, p=0.004) and waist circumference (β=0.116, p=0.02) were predictors of IR only in women, meanwhile none of the analyzed biomarkers predicted insulin-resistance in men. Besides, postmenopausal women presented higher adiponectin levels than premenopausal 7.63 (4.46-9.58) vs 5.50 (3.83-7.40) μg/ml, p=0.01.

CONCLUSIONS

Adiponectin and waist circumference are important predictors of insulin-resistance even in healthy non-diabetic women, they may open a new opportunity to improve current risk estimation.