Endogenous Steroids Research Articles

Liver function in transgender persons: Challenges in the COVID-19 era.

Transgender persons constitute a non-negligible percentage of the general population. Physical gender-transitioning in trans persons is mainly achieved with hormonal cross-sex therapy and sex reassignment surgeries that aim to align bodily appearance with gender identity. Hormonal treatment acts via suppressing the secretion of the endogenous sex hormones and replacing them with the hormones of the desired sex. The administration of testosterone is the typical masculinizing treatment in trans men, whilst trans women are routinely treated with estradiol agents in combination with anti-androgens or gonadotrophin-releasing hormone agonists if testes are present. Exogenous androgenic steroids, estradiol agents, and anti-androgens have been implicated in a series of hepatotoxic effects. Thus, liver integrity is a major concern with the long-term administration of cross-sex therapy. Hepatic tissue is susceptible to coronavirus disease 19 (COVID-19) through various pathophysiological mechanisms. Special consideration should be paid to minimize the risk of hepatic damage from the potential cumulative effect of COVID-19 and gender-affirming treatment in transgender patients. Appropriate care is significant, with continuous laboratory monitoring, clinical observation and, if needed, specific treatment, especially in severe cases of infection and in persons with additional liver pathologies. The pandemic can be an opportunity to provide equal access to care for all and increase the resilience of the transgender population.

Associations between endogenous sex hormone levels and adipokine levels in the Multi-Ethnic Study of Atherosclerosis.

Differences in sex hormone levels contribute to differences in cardiovascular disease (CVD) risk. Adipokines play a role in cardiometabolic pathways and have differing associations with CVD. Adipokine levels differ by sex; however, the association between sex hormone profiles and adipokines is not well established. We hypothesized that a more androgenic sex hormone profile would be associated with higher leptin and resistin and lower adiponectin levels among postmenopausal women, with the opposite associations in men. We performed an analysis of 1,811 adults in the Multi-Ethnic Study of Atherosclerosis who had both sex hormones and adipokines measured an average of 2.6 years apart. Sex hormones [Testosterone (T), estradiol (E2), sex hormone binding globulin (SHBG), and dehydroepiandrosterone (DHEA)] were measured at exam 1; free T was estimated. Serum adipokines (leptin, resistin, adiponectin) were measured at exams 2 or 3. We used multivariable linear regression to examine the cross-sectional associations between sex hormones and adipokines. The mean (SD) age was 63 (10) years, 48% were women; 59% non-White participants. For leptin, after adjusting for demographics only, higher free T and lower SHBG, were associated with higher leptin in women; this association was attenuated after further covariate adjustment. However in men, higher free T and lower SHBG were associated with greater leptin levels in fully adjusted models. For adiponectin, lower free T and higher SHBG were associated with greater adiponectin in both women and men after adjustment for CVD risk factors. For resistin, no significant association was found women, but an inverse association with total T and bioT was seen in men. Overall, these results further suggest a more androgenic sex profile (higher free T and lower SHBG) is associated with a less favorable adipokine pattern. These findings may provide mechanistic insight into the interplay between sex hormones, adipokines, and CVD risk.

Sex Hormones and Diabetes in 45- to 74-year-old Men and Postmenopausal Women: The Hispanic Community Health Study.

Previous studies demonstrated associations of endogenous sex hormones with diabetes. Less is known about their dynamic relationship with diabetes progression through different stages of the disease, independence of associations, and role of the hypothalamic-pituitary gonadal axis. The purpose of this analysis was to examine relationships of endogenous sex hormones with incident diabetes, prediabetes, and diabetes traits in 693 postmenopausal women and 1015 men aged 45 to 74 years without diabetes at baseline participating in the Hispanic Community Health Study/Study of Latinos and followed for 6 years. Baseline hormones included estradiol, luteinizing hormone (LH), follicle stimulating hormone (FSH), sex hormone-binding globulin (SHBG), dehydroepiandrosterone sulfate (DHEAS), and, in men, testosterone and bioavailable testosterone. Associations were analyzed using multivariable Poisson and linear regressions. In men, testosterone was inversely associated with conversion from prediabetes to diabetes (incidence rate ratio [IRR] for 1 SD increase in testosterone: 0.821; 95% CI, 0.676, 0.997; P = 0.046), but not conversion from normoglycemia to prediabetes. Estradiol was positively associated with increase in fasting insulin and homeostatic model assessment of insulin resistance. In women, SHBG was inversely associated with change in glycosylated hemoglobin, postload glucose, and conversion from prediabetes to diabetes (IRR = 0.62; 95% CI, 0.44, 0.86, P = 0.005) but not from normoglycemia to prediabetes. Relationships with other hormones varied across glycemic measures. Stronger associations of testosterone and SHBG with transition from prediabetes to diabetes than from normoglycemic to prediabetes suggest they are operative at later stages of diabetes development. Biologic pathways by which sex hormones affect glucose homeostasis await future studies.

PS-C28-6: HIGH TESTOSTERONE AND LOW ESTRADIOL SERA LEVELS ARE ASSOCIATED WITH UNSTABLE PLAQUE COMPOSITION IN MEN WITH SEVERE CAROTID ATHEROSCLEROSIS

Background and Objectives: Ischemic strokes caused by the rupture of unstable atherosclerotic plaques in the carotid arteries, are leading causes of mortality and disability worldwide. Sex differences exist in plaque composition, where men are more likely to develop unstable plaques than women. Sex hormones affect vascular reactivity and inflammation, but it remains unclear if they are involved in plaque instability and how their role differs in men and women. Herein, we investigated the association between circulating endogenous sex hormone levels and plaque composition/instability in men and women with severe carotid atherosclerosis. Design and method: Pre-operative fasting blood samples and plaque specimens were collected from post-menopausal women and men greater than 55 years old with severe carotid atherosclerosis who underwent a carotid endarterectomy at McGill-affiliated hospitals in Montreal, Canada. Plaque composition and stability were examined by experienced vascular pathologists according to gold-standard histological classifications. Liquid chromatography-tandem mass spectrometry-based methods were developed to quantify endogenous sex hormones, 17ß-estradiol (E2), testosterone, androstenedione, and dehydroepiandrosterone, in sera samples. Results: Subjects (n = 460) had a mean age of 71.0 ± 9.0, were 68.9% male, and had various comorbidities (hypercholesterolemia [82.6%], hypertension [84.6%], type 2 diabetes [34.5%]). Clinical characteristics were similar among post-menopausal women (n = 143) and men (n = 317) with stable versus unstable plaques. Men had a significantly greater proportion of unstable versus stable plaques compared to women (men unstable: 61.5%, women unstable: 41.3%; P < 0.001), characterized predominantly by a large lipid-rich core, hemorrhage, and high presence of inflammatory cell infiltration. Men with unstable plaques had significantly higher levels of testosterone than men with stable plaques (P = 0.004). In men, testosterone levels were inversely associated with fibrosis (P < 0.05), while directly associated with unstable plaque features, including greater lipid core size (P < 0.05), and a greater presence of foam cells (P < 0.05), neovascularization (P < 0.01), and plaque (P < 0.01) and cap inflammation (P < 0.05). No associations were observed between testosterone levels and plaque features in women. Endogenous E2 levels were inversely associated with neovascularization (P < 0.05) and plaque and cap inflammation (P < 0.001) in men, while inversely associated with fibrosis levels in women (P < 0.05). Conclusion: Our findings suggest that higher testosterone and lower E2 levels are associated with unstable plaque composition in men with carotid atherosclerotic disease and may partly explain the higher proportion of unstable plaques observed among men than women of similar age and comorbidity status. Instead, in women, estradiol appears to play a detrimental role in plaque instability by inversely affecting fibrous tissue levels (a key stabilizing feature of plaques).

Cortisol: Analytical and clinical determinants.

Cortisol, the main human glucocorticoid, is synthesized from cholesterol in the adrenal cortex and predominantly metabolized by the liver. Interpretation of quantitative results from the analysis of serum, urine and saliva is complicated by variation in circadian rhythm, response to stress as well as the presence of protein-bound and free forms. Interestingly, cortisol is the only hormone routinely measured in serum, urine, and saliva. Preanalytical and analytical challenges arise in each matrix and are further compounded by the use of various stimulation and suppression tests commonly employed in clinical practice. Although not yet included in clinical guidelines, measurement of cortisol in hair may be of interest in specific situations. Immunoassays are the most widely used methods in clinical laboratories to measure cortisol, but they are susceptible to interference from synthetic and endogenous steroids, generally producing a variable overestimation of true cortisol results, especially in urine. Analysis by mass spectrometry provides higher specificity and allows simultaneous measurement of multiple steroids including synthetic steroids, thus reducing diagnostic uncertainty. An integrated review of cortisol in various disease states is also addressed.

Current Evidence for the Involvement of Hypogonadism and Modulation of Steroid Receptors in Prostate Carcinoma

Prostate cancer (PCa) is the most prevalent cancer in the Nigerian male population, similar to other black populations. It is postulated that exposure to endogenous or environmental steroids prompts prostatic mediated changes via steroid receptors as well as a decrease in the androgen/estrogen ratio and aging. Thereby contributing to prostatic carcinogenesis and disease progression. This study is aimed to determine the plasma levels of testosterone, 17β-estradiol as well as the pattern of expression of steroid receptors in subjects with prostate cancer, benign prostatic hyperplasia, and controls. Study participants are made up of a total of 195 consented volunteers consisting of 65 Prostate cancer (PCa) and 65 benign prostatic hyperplasia (BPH) treatment naïve participants and 65 apparently healthy subjects as controls. Anthropometric data were measured using standard methods and biochemical parameters determined by enzyme-linked immunosorbent assay (ELISA). The gene expression is quantified by Real-Time PCR with PerfeCTa SYBR Green SuperMix on CFX96 Bio-Rad, USA. The results of this study showed increased levels of 17β-estradiol, total androgen receptor (AR) and estrogen receptor-beta (Erβ) in prostate cancer participants compared with controls (P<0.05). A Significant reduction in plasma levels of testosterone in prostate cancer subjects compared with BPH and controls was observed (P<0.001). The plasma levels of androgen receptors were significantly increased in PCa and BPH participants (p<0.05). We observed a positive correlation between ERβ levels and PSA levels in the PCa group (r=0.32, p=0.02). There was a differential expression of AR, ESR1 and ESR2 in the studied group. This study shows hypogonadism and an increased 17β-estradiol, ERβ, and AR levels in subjects with prostate cancer. This data suggests that modulation of these hormones and their receptors may be associated with initiation and progression of prostate cancer and could be valuable in the interpretation of PSA kinetics and stratification of cases after screening.

Assessment of the Androstenedione Assay on a Roche Analytical Platform and Comparison with Different Methods.

D4-androstenedione (D4ASD) is an intermediate hormone of androgen biosynthesis by the gonads and the adrenal glands. The interest in D4ASD concentration assessment resides in diagnostics of androgenic hyperproduction pathologies. Currently, many D4ASD quantification methods are available on the market including immunological methods that remain problematic due to the possible cross-reactivity with endogenous or exogenous steroids. Recently Roche® launched a new fully automated instrument for the measurement of D4ASD concentration. In this paper, the criteria of analytical performance (repeatability and intermediate precision) of the D4ASD Roche® assay were assessed and compared with 2 different methods including a radioimmunoassay (RIA) as well as a liquid chromatography tandem mass spectrometry (LC-MS/MS) method. Repeatability and intermediate precision of the D4ASD Roche® were acceptable according to the prede-fined RICOS standard (CV ≤ 7.9%) and the assay showed a good correlation with other assays considering the 95% CI obtained for the slope and the y-intercept. This method demonstrates acceptable criteria of analytical performance with an intermediate imprecision and a trueness within the fixed acceptance limits.

Antenatalni kortikosteroidi - između leka i rizika za razvoj fetusa i programiranja odrastanja

Antenatal corticosteroid therapy (ACST) is very important in reducing the sequelae of prematurity, respiratory distress syndrome (RDS), intraventricular hemorrhage (IVH), and necrotizing enterocolitis (NEC). This therapy has short-term and long-term neonatal consequences that range from reduced neonatal body weight, brain growth, hypertension, hypoglycemia and obesity to delayed neurological development. In addition to undeniable importance this type of therapy has on fetal maturation, it may also impact programming of fetuses future development and health during childhood and adulthood. ACST must be personalized, as a single course, and determined by indications and assessment of the expected time of delivery, so that the exposure time of the fetus to the effects of endogenous and exogenous steroids is shortened.

Investigating the biosynthesis and metabolism of 11β-hydroxyandrostenedione.

The "rediscovery" 11β-hydroxyandrostenedione (11OHA4) placed the spotlight on this unique adrenal-derived hormone with researchers and clinicians once again focusing on the steroid's presence in endocrine pathology. Little was known about the steroid other than its chemical characterisation and that a mitochondrial cytochrome P450 enzyme catalysed the 11β-hydroxylation of 11OHA4. The fact that neither the biosynthesis nor metabolism of 11OHA4 had been fully characterised presented an ideal opportunity to investigate the metabolic pathways. In addition, methodologies and analytical tools have improved vastly since 11OHA4 was first identified in the 1950s. Cell models, recombinant DNA technology and steroid quantification using liquid chromatography mass spectrometry have greatly facilitated investigations in the field of steroidogenesis. Evident from the structure is that 11OHA4 can be metabolised by hydroxysteroid dehydrogenases and reductases acting on the C4/C5 double bond and on functional moieties at specific carbons on the cyclopentane-perhydro-phenanthrene backbone of the steroid. In this chapter, the biosynthesis and metabolism of 11OHA4 is followed using two strategies that complement each another; (i) human cell models either transiently transfected with recombinant DNA or expressing endogenous steroidogenic enzymes and (ii) steroid identification and quantification using high resolution mass spectrometry. These methodologies have proven invaluable in the determination of 11OHA4's metabolic route. Both strategies are presented with the focus on the accurate identification and quantification of steroids using UHPLC-MS/MS and UPC2-MS/MS. The protocols described in this chapter lay a sound foundation which can aid the researcher and be adapted and implement in future studies.

Genomic and non-genomic effects of glucocorticoids in respiratory diseases.

Cortisol is an endogenous steroid hormone essential for the natural resolution of inflammation. Synthetic glucocorticoids (GCs) were developed and are currently amongst the most widely prescribed anti-inflammatory drugs in our modern clinical landscape owing to their potent anti-inflammatory activity. However, the extent of GC's effects has yet to be fully elucidated. Indeed, GCs modulate a broad spectrum of cellular activity, from their classical regulation of gene expression to acute non-genomic mechanisms of action. Furthermore, tissue specific effects, disease specific conditions, and dose-dependent responses complicate their use, with side-effects potentially plaguing their use. It is thus vital to outline and consolidate the effects of GCs, to demystify and maximize their therapeutic potential while avoiding pitfalls that would otherwise render them obsolete.

Single-run UHPLC-MS/MS method for simultaneous quantification of endogenous steroids and their phase II metabolites in serum for anti-doping purposes

Anti-doping rule violations related to the abuse of endogenous anabolic androgenic steroids can be currently discovered by the urinary steroidal module of Athlete Biological Passport. Since this powerful tool is still subjected to some limitations due to various confounding factors altering the steroid profile, alternative strategies have been constantly proposed. Among these, the measurement of blood concentrations of endogenous steroid hormones by LC-MS is currently of increasing interest in anti-doping, bringing significant advantages for the detection of testosterone abuse in females and in individuals with deletion of UGT2B17 enzyme. Although various research groups have made significant efforts in method development, there is currently no accepted or harmonized anti-doping method for quantitative analysis of the various testosterone doping markers in blood. In this study we present a UHPLC-MS/MS method for the quantification of major circulating steroid hormones together with an extended panel of glucuro- and sulpho-conjugated phase II metabolites of androgens. Chromatographic setup was optimized by comparing the performance of three different C18 stationary phases and by the careful selection of mobile phases with the aim of separating all the target steroids, including numerous isomeric/isobaric compounds. MS parameters were fine-tuned to obtain the sensitivity needed for measuring the target analytes, that show specific serum concentrations ranging from low pg/mL for less abundant compounds to μg/mL for sulpho-conjugated steroids. Finally, sample preparation protocol was developed for the extraction of steroid hormones from 200 μL of serum and the performance was evaluated in terms of extraction recovery and matrix effect. The final method was then applied to authentic serum samples collected from healthy volunteers (40 males and 40 females) at the Blood Bank of the City of Health and Science University Hospital of Turin. The analysis of these samples allowed to obtain results on serum concentrations of the targeted steroids, with particular emphasis on previously undiscovered phase II metabolites, such as the isomers of 5-androstane-3,17-diol glucuronide. This preliminary application also enabled measuring dihydrotestosterone sulphate in male samples, efficiently separating this analyte from its isomer, epiandrosterone sulphate, which circulates in blood at high concentrations.The promising results of this study are encouraging for the measurement of blood steroid profile markers in serum and plasma samples for Athlete Biological Passport purposes.

Short-term depletion of plasma estrogen affects hypothalamic kisspeptin-neurokinin B-dynorphin A neurons, gonadotrophs, and pulsatile luteinizing hormone secretion in female rats

Kisspeptin-neurokinin B-dynorphin A (KNDy) neurons in the arcuate nucleus (ARC) regulate pulsatile luteinizing hormone (LH) secretion. These neurons express estrogen receptors and are negatively regulated by estrogen. This study aimed to determine whether estrogen supplementation after short-term ovariectomy-induced estrogen depletion has different effects on KNDy neurons depending on the timing of the supplementation. To decrease endogenous estradiol (E2) for a short time, adult female rats received a tube filled with E2 one week after ovariectomy and utilized it one week later (O1w + E). From the results of immunohistochemistry, the response to E2 was attenuated in KNDy neurons of O1w + E rats. Enlarged LH-secreting cells in the anterior pituitary were found in O1w + E rats; however, such enlarged LH cells were not found in ones without previous short-term E2 depletion. From the analysis of LH pulses, plasma LH levels were increased in O1w + E rats relative to ones without previous short-term E2 depletion. These results suggested that once endogenous sex steroids were depleted, the response to E2 in hypothalamic KNDy neurons did not fully recover in one week. Thus, short-term sex steroid depletion due to gonadectomy could alter the response to the sex steroids in KNDy neurons even though the period without sex steroids is only one week, and the alteration is likely to affect plasma hormone levels.

Endogenous Steroid Hormone Concentrations and Risk of Endometriosis in Nurses' Health Study II.

Few studies have assessed the association between endogenous steroid hormone levels and a subsequent diagnosis of endometriosis. We prospectively evaluated premenopausal plasma sex hormone levels and the risk of laparoscopically confirmed endometriosis in a nested case-control study within Nurses' Health Study II. Between blood collection (1996-1999) and 2009, we ascertained 446 women with incident endometriosis and matched them to 878 controls through risk-set sampling. We conducted multivariable conditional logistic regression accounting for matching and confounders to estimate relative risks (RRs) and 95% confidence intervals (CIs). Women with greater early follicular-phase total or free estradiol levels had a nonlinear increased risk of endometriosis (early follicular total estradiol: second quartile vs. first, RR=2.23 (95% CI: 1.44, 3.47); third quartile, RR=1.83 (95% CI: 1.16, 2.88); fourth quartile, RR=1.68 (95% CI: 1.05, 2.68); early follicular free estradiol: second quartile vs. first, RR=1.63 (95% CI: 1.05, 2.54); third quartile, RR=2.02 (95% CI: 1.31, 3.12); fourth quartile, RR=1.04 (95% CI: 0.66, 1.65)). Free testosterone assessed in quartile categories was not associated with endometriosis, although a threshold effect was observed, with a positive association among women in the top 2% of free testosterone levels. Levels of mid-luteal-phase total and free estradiol, follicular and luteal estrone, total testosterone, progesterone, and sex hormone binding globulin were not associated with endometriosis risk. These results support the role of sex steroids in endometriosis etiology, although the relationships suggest complex threshold effects.

Study of Acute Coronary Syndrome in Premenopausal Women in Correlation with Sex Hormones

Objectives: Higher testosterone and lower Estrogen levels are associated with cardiovascular disease in women. However, studies on endogenous sex hormones and acute coronary syndrome (ACS) in pre-menopausal women are sparse. Material and Methods: We studied 50 pre-menopausal women presenting with ACS and age-matched controls who consented to the study with Testosterone, Estradiol, and Sex hormone-binding globulin (SHBG) levels at baseline. They were clinically followed up for 6 months duration. Results: The mean age was 37.42 ± 5.7 years. 48% patients were obese. The mean body mass index was 27.53 ± 5.41 kg/m2. Hypertension followed by Diabetes was the most common risk factor. 14% had family history of coronary artery disease (CAD). 24% had atypical chest pain at presentation. Anterior wall ST elevation myocardial infarction was the most common presentation. Single-vessel disease was seen in 38%; 24% had Non-Obstructive CAD. Ratios of Bioavailable Testosterone: Estradiol, Estradiol: Low-density Lipoprotein (LDL), Estradiol: High-density Lipoprotein, SHBG: LDL, and SHBG: HbA1c were analyzed in cases and controls and were not found to be significantly associated. Conclusion: Endogenous sex hormones were not found to be significantly associated with ACS in premenopausal women.

Semi-automated serum steroid profiling with tandem mass spectrometry

ObjectivesHighly selective and sensitive multi-analyte methods for the analysis of steroids are attractive for the diagnosis of endocrine diseases. Commercially available kits are increasingly used for this purpose. These methods involve laborious solid phase extraction, and the respective panels of target analytes are incomplete. We wanted to investigate whether an improvement of kit solutions is possible by introducing automated on-line solid phase extraction (SPE) and combining originally separate analyte panels. MethodsSample preparation was performed using automated on-line SPE on a high-pressure stable extraction column. Chromatographic separation, including isobaric compounds, was achieved using a 0.25 mM ammonium fluoride-methanol gradient on a small particle size biphenyl column. Standard compounds and internal standard mixtures of two panels of a commercially available kit were combined to achieve an optimized and straightforward detection of 15 endogenous steroids. Validation was performed according to the European Medicines Agency (EMA) guidelines with slight modifications. ResultsValidation was successfully performed for all steroids over a clinically relevant calibration range. Deviations of intra- and inter-assay accuracy and precision results passed the criteria and no relevant matrix effects were detected due to highly effective sample preparation. External quality assessment samples showed the applicability as a routine diagnostic method, which was affirmed by the analyses of anonymized clinical samples. ConclusionsIt was found possible to complement a commercially available kit for quantitative serum steroid profiling based on isotope dilution LC-MS/MS by implementing automated on-line SPE, thereby improving the practicality and robustness of the measurement procedure.

Detection of 20 endogenous anabolic steroid esters with Girard’s Reagent P derivatization in dried blood spots using UPLC-Q-Orbitrap-MS

The esters of endogenous anabolic steroids are the most frequently used doping agents for prolonging the half-life of exogenously ingested endogenous anabolic steroids. As a cost- and time-saving matrix, dried blood spots (DBSs) are valuable for directly detecting endogenous anabolic steroid esters in blood and for providing conclusive evidence of their abuse. In this study, a method for simultaneous detection of 20 endogenous anabolic steroid esters in DBSs based on ultra-high performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap-MS) with parallel reaction monitoring (PRM) was developed and validated, and 10 of these esters were analyzed in DBSs for the first time. This method analyzes the greatest number and types of endogenous anabolic steroid esters of any current method using DBSs. Girard’s Reagent P (GRP) was used for the derivatization of endogenous anabolic steroid esters in a DBS matrix for the first time, and the conditions of the derivatization reaction were optimized to achieve a higher sensitivity compared to previous methods. Selectivity, limit of detection (LOD), extraction recovery, precision (intra- and inter-), matrix effects, and carry-over were analyzed to validate the method. The LODs were lower and the recoveries were higher than those of previous studies. The relative standard deviation of the intraday precision was below 20% and the interday precision was below 35%. A product ion analysis of GRP nandrolone ester, GRP boldenone ester, GRP dehydroepiandrosterone acetate, and GRP androstanolone ester derivatives was performed, and the structures of the fragment ions were proposed for the first time.

Dietary energy intake across the menstrual cycle: a narrative review.

Females are often underrepresented in the scientific literature, but awareness of the need for female-specific research is increasing. Review articles have been published on the effects of the menstrual cycle on aspects of exercise performance and physiology, yet to date no research has reviewed the effect of menstrual cycle phase on dietary energy intake. Fluctuations in endogenous sex hormones across the menstrual cycle influence a range of physiological processes, including those involved in nutritional status. Observational research typically quantifies female athletes' nutritional intakes at a single time point; however, this may provide inaccurate information if dietary intake fluctuates across the menstrual cycle. Similarly, this may have implications for interventional research, where dietary intake is often poorly controlled or monitored. This review aimed to synthesize the published literature on dietary energy intakes of naturally menstruating females in various phases of the menstrual cycle. The review critiques the relevant literature in light of recent publications on good practice for female research, explores the impact of the menstrual cycle on energy intake, identifies gaps within the evidence base, and informs future research. Overall, energy intake appears to be lower in the follicular phase compared with the luteal phase, with a particular decrease in the days leading up to and including ovulation. The magnitude of these fluctuations is not yet clearly quantifiable and most likely varies, both between individuals, and from cycle to cycle. This review notes the lack of high-quality research investigating the energy intakes of females across the menstrual cycle, and the very limited data available for female athletes and others who undertake large amounts of physical activity. It also highlights the need for researchers to take into consideration anovulatory cycles and the potential effects of premenstrual disorders on dietary intake.

Abstract 9737: Association of Endogenous Sex Hormone Levels and Myocardial Fibrosis in Men and Post-menopausal Women: The Multi-Ethnic Study of Atherosclerosis

Introduction: Endogenous sex hormone(ESH) imbalances have been linked to a higher risk of heart failure in men and post-menopausal women(PMW). However, experimental studies have found conflicting results regarding ESH' response to myocardial fibrosis(MF). Hypothesis: We hypothesize that at baseline, men and PMW with abnormal ESH profiles will have higher rates of MF measured by CMR T1 mapping and higher rates of myocardial scar detected by CMR during a ten-year follow up. Methods: A total of 1,276 men and 1,048 PMW were included in the MESA with ESH measured at baseline and had undergone CMR 10 years later. All analyses were stratified by sex and age groups (Table1A-B). Multivariable linear regression models were constructed to assess the associations of baseline ESH, ECV, and nativeT1 time. Multivariable logistic regression models were built to determine the associations of baseline ESH and myocardial scar among men. Results: Each 1-SD increment higher free and bioavailable testosterone in older men (≥65) was associated with 2.5% (p=0.008) and 1.0%(p=0.08) lower ECV, respectively, and 21.5%(p=0.03) and13.4%lower native T1(p=0.02). A 1-SD increment greater SHBG level was associated with 2%(p=0.01) higher ECV and 12% higher native T1 (p=0.08)(Table1A). Among post-menopausal women of 44-54 years, a 1-SD increment higher free testosterone was associated with 14% greater native T1 only; however, those between 55-64 years, a 1-SD increment higher total testosterone was associated with 9% lower native T1 (Table1B). Higher levels of estradiol in older men (≥65 years) were independently associated with a significantly higher odds of having a myocardial scar (OR:4.10,95%CI:1.35-12.40;p=0.01). Conclusions: Among older men, lower free testosterone and higher levels of estradiol were independently associated with CMR-defined interstitial MF and replacement fibrosis, respectively. There was no consistent association between ESH and interstitial MF among PMW.

Simultaneous determination of sex hormones and bile acids in rat plasma using a liquid chromatography-tandem mass spectrometry method

Endogenous steroids, including sex hormones and bile acids, are a group of essential compounds with various biological functions. In this study, we developed an LC-MS method that simultaneously measures 14 sex hormones and metabolites (SH) and 32 bile acids (BA) in rat plasma. Multiple innovative approaches were applied to increase the sensitivity and specificity, including optimization of the mobile phases, gradients, and dynamic multiple reaction monitoring (DMRM) transitions. The method was validated and applied on plasma samples from pregnant rats before and 0.5 h after oral glucose tolerance test (OGTT) at gestational days 0.5 and 18.5. Results showed that the method was applicable, and 9 SH and 30 BA were measurable in the samples. In summary, this method is applicable in studies on SH and BA in rat plasma, and may also be used on other matrix and species.

OR05-5 Body Mass Index (BMI) as a Predictor of Bone Mineral Density (BMD) in Gender Diverse Youth

Abstract Objective GnRH agonists (GnRHa), used to prevent development of undesired secondary sex characteristics for gender diverse youth (GDY), may impede pubertal bone mineral accrual increasing the risk for osteopenia/osteoporosis during adulthood. Based on findings of low bone mineral density (BMD) scores (relative to natal sex) prior to GnRHa [1], we hypothesized BMD might be associated with body mass index (BMI) in GDY.Method: To test our hypothesis, we reviewed medical records for 27 GDY; 16 were designated female at birth (DFAB) and 11 were designated male at birth (DMAB). Age at presentation, gender identity, ages at initiation of GnRHa and gender affirming hormone treatment (GAHT), duration of GnRHa treatment prior to GAHT initiation, auxologic parameters including BMI, and lumbar spine BMD obtained from GE lunar IDXa dual-energy X-ray absorptiometry (DEXA) were extracted. Lumbar spine BMD was used for statistical analysis. Statistical analysis was performed with Microsoft Excel Analysis ToolPak. A linear regression model was used to determine significance of BMI and GnRHa as predictors of BMD Z-score using a significance level of 0.05. Legal gender marker was used to determine BMD Z-scores. Results BMI ranged from 16.93 kg/m2 to 35.79 kg/m2 (5th to the 99th percentile). DEXA scan results were available for 27 GDY with age range 10-25 years; mean age (±SD) was 17±3 years. BMD of the lumbar spine was obtained from 0-61 months (mean 30 ± 21 months) following initiation of GnRHa. Length of GnRHa treatment prior to GAHT initiation ranged from 0-53 months (mean 14 ± 12 months).Individuals were at different stages of the gender affirmation process including 1) No medical treatments, 2) GnRH agonist only, 3) GAHT only, and 4) combined GnRH agonist and GAHT. Using a linear regression model, length of GnRHa therapy and length of GnRHa without GAHT were not significantly associated with lumbar spine BMD in our sample (p = 0.44 and 0.29, respectively). Using a linear regression model, BMI was a significant positive predictor of higher lumbar bone mineral density (p = 0.03). Conclusion Sex hormone exposure during adolescence and young adulthood is essential for bone health. While GnRH agonists lower endogenous sex hormone exposure, in our sample, lower BMD was not associated with total duration of GnRHa therapy or duration of GnRHa treatment prior to GAHT. Rather BMD was positively associated with BMI regardless of gender affirming medical therapies. Limitations include small sample size, retrospective design, and the use of legal gender marker for normative values. The next step will be larger, prospective studies to identify predictors of low BMD in GD youth. This information will guide future management regarding BMD monitoring.