Effects of testosterone therapy for women: a systematic review and meta-analysis protocol

Low testosterone levels relate to poorer cognitive function in women in an APOE-ε4-dependant manner

BACKGROUND

Past research suggests that low testosterone levels relate to poorer cognitive function and higher Alzheimer's disease (AD) risk; however, these findings are inconsistent and are mostly derived from male samples, despite similar age-related testosterone decline in females. Both animal and human studies demonstrate that testosterone's effects on brain health may be moderated by apolipoprotein E ε4 allele (APOE-ε4) carrier status, which may explain some previous inconsistencies. We examined how testosterone relates to cognitive function in older women versus men across healthy aging and the AD continuum and the moderating role of APOE-ε4 genotype.

METHODS

Five hundred and sixty one participants aged 55-90 (155 cognitively normal (CN), 294 mild cognitive impairment (MCI), 112 AD dementia) from the Alzheimer's Disease Neuroimaging Initiative (ADNI), who had baseline cognitive and plasma testosterone data, as measured by the Rules Based Medicine Human DiscoveryMAP Panel were included. There were 213 females and 348 males (self-reported sex assigned at birth), and 52% of the overall sample were APOE-ε4 carriers. We tested the relationship of plasma testosterone levels and its interaction with APOE-ε4 status on clinical diagnostic group (CN vs. MCI vs. AD), global, and domain-specific cognitive performance using ANOVAs and linear regression models in sex-stratified samples. Cognitive domains included verbal memory, executive function, processing speed, and language.

RESULTS

We did not observe a significant difference in testosterone levels between clinical diagnostic groups in either sex, regrardless of APOE-ε4 status. Across clinical diagnostic group, we found a significant testosterone by APOE-ε4 interaction in females, such that lower testosterone levels related to worse global cognition, processing speed, and verbal memory in APOE-ε4 carriers only. We did not find that testosterone, nor its interaction with APOE-ε4, related to cognitive outcomes in males.

CONCLUSIONS

Findings suggest that low testosterone levels in older female APOE-ε4 carriers across the aging-MCI-AD continuum may have deleterious, domain-specific effects on cognitive performance. Although future studies including additional sex hormones and longitudinal cognitive trajectories are needed, our results highlight the importance of including both sexes and considering APOE-ε4 carrier status when examining testosterone's role in cognitive health.

The Impact of Testosterone Therapy on Cardiovascular Risk Among Postmenopausal Women

Purpose

To summarize the current state of knowledge surrounding the impact of testosterone therapy on cardiovascular risk factors in postmenopausal women.

Methodology

In this scoping review, a comprehensive search of peer-reviewed literature was conducted in adherence to a methodological framework comprising 4 distinct stages: conceptualizing a comprehensive search strategy, screening relevant publications, extracting pertinent data, and organizing and synthesizing the resultant findings. The search used electronic databases, including MEDLINE, Embase, and Google Scholar, to ensure an exhaustive survey of the available literature.

Results

The database search yielded 150 articles, including systematic reviews, registered trials, and peer-reviewed studies, of which 48 duplicates were removed. Following the title/abstract screening, 36 publications were included in the full-text review. On completion of the full-text review, using the inclusion/exclusion criteria, 29 articles were excluded and 7 remained for data extraction and qualitative synthesis.

Main Conclusion

Existing research provides promising insights into the benefits of low-dose testosterone therapy, typically combined with estrogen therapy. These benefits may include positive impacts on body composition, functional capacity, insulin sensitivity, inflammatory markers, and cholesterol. However, there remains a substantial lack of knowledge surrounding the effects and mechanisms behind testosterone therapy in postmenopausal women in relation to its impacts on cardiovascular risk. High-quality, evidence-based clinical intervention research is needed to investigate testosterone therapy's potential implication on cardiovascular risk factors in post-menopausal women.

Sexual attraction to visual sexual stimuli in association with steroid hormones across menstrual cycles and fertility treatment

BACKGROUND

Steroid hormones (i.e., estradiol, progesterone, and testosterone) are considered to play a crucial role in the regulation of women's sexual desire and sexual attraction to sexual stimuli throughout the menstrual cycle. However, the literature is inconsistent, and methodologically sound studies on the relationship between steroid hormones and women's sexual attraction are rare.

METHODS

This prospective longitudinal multisite study examined estradiol, progesterone, and testosterone serum levels in association with sexual attraction to visual sexual stimuli in naturally cycling women and in women undergoing fertility treatment (in vitro fertilization, IVF). Across ovarian stimulation of fertility treatment, estradiol reaches supraphysiological levels, while other ovarian hormones remain nearly stable. Ovarian stimulation hence offers a unique quasi-experimental model to study concentration-dependent effects of estradiol. Hormonal parameters and sexual attraction to visual sexual stimuli assessed with computerized visual analogue scales were collected at four time points per cycle, i.e., during the menstrual, preovulatory, mid-luteal, and premenstrual phases, across two consecutive menstrual cycles (n = 88 and n = 68 for the first and second cycle, respectively). Women undergoing fertility treatment (n = 44) were assessed twice, at the beginning and at the end of ovarian stimulation. Sexually explicit photographs served as visual sexual stimuli.

RESULTS

In naturally cycling women, sexual attraction to visual sexual stimuli did not vary consistently across two consecutive menstrual cycles. While in the first menstrual cycle sexual attraction to male bodies, couples kissing, and at intercourse varied significantly with a peak in the preovulatory phase, (all p ≤ 0.001), there was no significant variability across the second cycle. Univariable and multivariable models evaluating repeated cross-sectional relationships and intraindividual change scores revealed no consistent associations between estradiol, progesterone, and testosterone and sexual attraction to visual sexual stimuli throughout both menstrual cycles. Also, no significant association with any hormone was found when the data from both menstrual cycles were combined. In women undergoing ovarian stimulation of IVF, sexual attraction to visual sexual stimuli did not vary over time and was not associated with estradiol levels despite intraindividual changes in estradiol levels from 122.0 to 11,746.0 pmol/l with a mean (SD) of 3553.9 (2472.4) pmol/l.

CONCLUSIONS

These results imply that neither physiological levels of estradiol, progesterone, and testosterone in naturally cycling women nor supraphysiological levels of estradiol due to ovarian stimulation exert any relevant effect on women's sexual attraction to visual sexual stimuli.

Pharmacotherapy in Cachexia: A Review of Endocrine Abnormalities and Steroid Pharmacotherapy

Cachexia is a state of increased metabolism associated with high morbidity and mortality. Dysregulation of cytokines and hormone activity causes reduced protein synthesis and excessive protein breakdown. various treatments are available, depending on the primary disease and the patient's state. Besides pharmacological treatment, crucial is nutritional support as well as increasing physical activity. The main purpose of pharmacological treatment is to diminish inflammation, improve appetite and decrease muscle wasting. Therefore a lot of medications aim at proinflammatory cytokines such as Interferon-α or Tumor Necrosis Factor-β, but because of the complicated mechanism of cachexia, the range of targets is very wide. in cachexia treatment, use of corticosteroids is common, which improve appetite, diminish inflammation, inhibit prostaglandin metabolism, Interleukin-1 activity. They can also decrease protein synthesis and increase protein degradation, which can be prevented by resveratrol. Estrogen analogs, progesterone analogs, testosterone analogs, Selective Androgen Receptor Modulators (SARM), Angiotensin-Converting-Enzyme Inhibitors (ACEI), Nonsteroidal anti-inflammatory drugs (NSAIDs), thalidomide, melatonin, Growth Hormone Releasing Peptide-2 (GHRP-2) may play important role in wasting syndrome treatment as well. However, for the usage of some of them, evidence-based recommendations are not available. This review highlights current therapeutic options for cachexia with a specific focus on steroid therapy.

Androgen therapy for women after menopause

Androgens are essential hormones in women. Yet, androgen therapy is understudied and underutilized despite showing improvement in postmenopausal hypoactive sexual desire disorder (HSDD) and the genitourinary syndrome of menopause (GSM). Additionally, regulatory concerns have left a significant gap in commercially available testosterone preparations, formulated specifically for women, in most countries. This has led to off-label use of male formulations and compounded therapies which are under-regulated. Beyond HSDD and GSM, testosterone likely influences the brain, breast, cardiovascular and musculoskeletal systems. These effects are not well studied, and therefore it is difficult to counsel patients on testosterone therapy when used for these endpoints. Ultimately, further study is needed to elucidate these effects, create a fuller picture of the risks and benefits, and encourage product development specifically designed for women.

Energy Metabolism Focused Analysis of Sexual Dimorphism in Biological Aging and Hypothesized Sex-specificity in Sirtuin Dependency

The process of biological aging or senescence refers to the gradual loss of homeostasis and subsequent loss of function - leading to higher chances of mortality. Many mechanisms and driving forces have been suggested to facilitate the evolution of a molecular circuit acting as a trade-off between survival and proliferation, resulting in senescence. A major observation on biological aging and longevity in humans and model organisms is the prevalence of significant sexual divergence in the onset, mechanisms and effects of aging associated processes. In the current account, we describe possible mechanisms by which aging, sex and reproduction are evolutionarily intertwined in order to maintain systemic energy homeostasis. We also interrogate existing literature on the sexual dimorphism of genetic, cellular, metabolic, endocrine and epigenetic processes driving cellular and systemic aging. Subsequently, based on available evidence, we propose a hypothetic model of sex-limited decoupling of female longevity from sirtuins, a major family of regulator proteins of the survival-proliferation trade-off. We also provide necessary considerations to be made in order to test the hypothesis and explore the physiological and therapeutic implications of this decoupling event in male and female longevity after reaching reproductive maturity. HYPOTHESIS STATEMENT: Sirtuins provide survival benefits in a sex-nonspecific manner but the dependency on sirtuins in driving metabolic networks after reaching reproductive maturity is evolutionarily decoupled from female longevity.

The role of androgens in women's health and wellbeing

Androgens in women, as well as in men, are intrinsic to maintenance of (i) reproductive competency, (ii) cardiac health, (iii) appropriate bone remodeling and mass retention, (iii) muscle tone and mass, and (iv) brain function, in part, through their mitigation of neurodegenerative disease effects. In recognition of the pluripotency of endogenous androgens, exogenous androgens, and selected congeners, have been prescribed off-label for several decades to treat low libido and sexual dysfunction in menopausal women, as well as, to improve physical performance. However, long-term safety and efficacy of androgen administration has yet to be fully elucidated. Side effects often observed include (i) hirsutism, (ii) acne, (iii) deepening of the voice, and (iv) weight gain but are associated most frequently with supra-physiological doses. By contrast, short-term clinical trials suggest that the use of low-dose testosterone therapy in women appears to be effective, safe and economical. There are, however, few clinical studies, which have focused on effects of androgen therapy on pre- and post-menopausal women; moreover, androgen mechanisms of action have not yet been thoroughly explained in these subjects. This review considers clinical effects of androgens on women's health in order to prevent chronic diseases and reduce cancer risk in gynecological tissues.

Safety and efficacy of testosterone for women: a systematic review and meta-analysis of randomised controlled trial data

BACKGROUND

The benefits and risks of testosterone treatment for women with diminished sexual wellbeing remain controversial. We did a systematic review and meta-analysis to assess potential benefits and risks of testosterone for women.

METHODS

We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science for blinded, randomised controlled trials of testosterone treatment of at least 12 weeks' duration completed between Jan 1, 1990, and Dec 10, 2018. We also searched drug registration applications to the European Medicine Agency and the US Food and Drug Administration to identify any unpublished data. Primary outcomes were the effects of testosterone on sexual function, cardiometabolic variables, cognitive measures, and musculoskeletal health. This study is registered with the International Prospective Register of Systematic Reviews (PROSPERO), number CRD42018104073.

FINDINGS

Our search strategy retrieved 46 reports of 36 randomised controlled trials comprising 8480 participants. Our meta-analysis showed that, compared with placebo or a comparator (eg, oestrogen, with or without progestogen), testosterone significantly increased sexual function, including satisfactory sexual event frequency (mean difference 0·85, 95% CI 0·52 to 1·18), sexual desire (standardised mean difference 0·36, 95% CI 0·22 to 0·50), pleasure (mean difference 6·86, 95% CI 5·19 to 8·52), arousal (standardised mean difference 0·28, 95% CI 0·21 to 0·35), orgasm (standardised mean difference 0·25, 95% CI 0·18 to 0·32), responsiveness (standardised mean difference 0·28, 95% CI 0·21 to 0·35), and self-image (mean difference 5·64, 95% CI 4·03 to 7·26), and reduced sexual concerns (mean difference 8·99, 95% CI 6·90 to 11·08) and distress (standardised mean difference -0·27, 95% CI -0·36 to -0·17) in postmenopausal women. A significant rise in the amount of LDL-cholesterol, and reductions in the amounts of total cholesterol, HDL-cholesterol, and triglycerides, were seen with testosterone administered orally, but not when administered non-orally (eg, by transdermal patch or cream). An overall increase in weight was recorded with testosterone treatment. No effects of testosterone were reported for body composition, musculoskeletal variables, or cognitive measures, although the number of women who contributed data for these outcomes was small. Testosterone was associated with a significantly greater likelihood of reporting acne and hair growth, but no serious adverse events were recorded.

INTERPRETATION

Testosterone is effective for postmenopausal women with low sexual desire causing distress, with administration via non-oral routes (eg, transdermal application) preferred because of a neutral lipid profile. The effects of testosterone on individual wellbeing and musculoskeletal and cognitive health, as well as long-term safety, warrant further investigation.

FUNDING

Australian National Health and Medical Research Council.

Imbalance in the Blood Concentrations of Selected Steroids in Pre-pubertal Gilts Depending on the Time of Exposure to Low Doses of Zearalenone

Zearalenone (ZEN) is a mycotoxin that not only binds to estrogen receptors, but also interacts with steroidogenic enzymes and acts as an endocrine disruptor. The aim of this study was to verify the hypothesis that low doses, minimal anticipated biological effect level (MABEL), no-observed-adverse-effect level (NOAEL) and lowest-adverse-effect level (LOAEL), of ZEN administered orally for 42 days can induce changes in the peripheral blood concentrations of selected steroid hormones (estradiol, progesterone and testosterone) in pre-pubertal gilts. The experiment was performed on 60 clinically healthy gilts with average BW of 14.5 ± 2 kg, divided into three experimental groups and a control group. Group ZEN5 animals were orally administered ZEN at 5 μg ZEN/kg BW, group ZEN10 - at 10 μg ZEN/kg BW, group ZEN15 - at 15 μg ZEN/kg BW, whereas group C received a placebo. Five gilts from every group were euthanized on analytical dates 1, 2 and 3 (days 7, 14 and 42 of the experiment). Qualitative and quantitative changes in the biotransformation of low ZEN doses were observed. These processes were least pronounced in group ZEN5 (MABEL dose) where ZEN metabolites were not detected on the first analytical date, and where β-ZEL was the predominant metabolite on successive dates. The above was accompanied by an increase in the concentration of estradiol (E2) which, together with "free ZEN", probably suppressed progesterone (P4) and testosterone (T) levels.