Measurement Of Testosterone Research Articles

The effects of a land-based warm-up and accompanying passive heat retention on core body temperature, hormones, and subsequent performance in elite surfers.

Surfing is a high participation sport, yet little sport science research exists regarding competitive performance in surfing. Given surfing's inclusion as an Olympic sport from the 2020 Tokyo Olympics onwards, an examination of performance would seem useful. In numerous land-based sports, and in swimming, the importance of a warm-up and muscle heat is well documented. However, surfing is a unique sport in that it is undertaken both above and below water. Therefore, the aim of this study was to explore the effectiveness of a warm-up in terms of readiness to perform in surfing. We discuss this in the context of thermal regulation, hormone profile change, and the subsequent expression of "power" on waves-a key criteria that surfers are scored for. Nineteen advanced level surfers (i.e., competitive at just below national level in Australia; n = 15 males and n = 4 females) with mean (±SD) age, height, and weight of 24.5 ± 11.6 years, 174.7 ± 9.1 cm, and 67.7 ± 10.2 kg, respectively, were recruited. We adopted a repeated measures pre- and post-design whereby participants engaged in several simulated surfing competitions in an artificial wave pool; once after an active warm-up combined with a passive heat retention strategy (i.e., wrapping themselves in survival blankets-treatment), and once after no warm-up (control). Saliva samples were collected pre- and post-active warm-up, or at equivalent times under control conditions, for the measurement of testosterone and cortisol. Increases in these hormones have previously been associated with an enhanced readiness to compete. Our results demonstrate a clear thermoregulatory benefit from the treatment, with the participants' core body temperatures typically higher from the end of the warm-up to the end of the surf session following treatment (p ≤ 0.03), and a magnitude of increase in core body temperature once in the water that is greater following treatment (p = 0.01). A small magnitude upward change in testosterone (p = 0.01) and cortisol (p ≤ 0.001) following warm-up was also observed. Finally, warm-up was associated with an improved wave performance compared with the control, with a 20% increase in the performance score typically observed (p ≤ 0.01). We argue that the improved thermal profile may have influenced power and, as such, surfing performance was enhanced.

EMAS position statement: Testosterone replacement therapy in older men.

Late-onset hypogonadism is the clinical entity characterised by low testosterone concentrations associated with clinical symptoms in the absence of organic disease in ageing men. It has been associated with metabolic syndrome, reduced bone mineral density, and increased cardiovascular morbidity and mortality risk. Although testosterone replacement therapy (TRT) reverses most of these conditions in young hypogonadal men, the risk/benefit ratio of TRT in older men is debatable. To update the 2015 EMAS statement on TRT in older men with new research on late-onset hypogonadism and TRT. Literature review and consensus of expert opinion. TRT should be offered only to symptomatic older men with confirmed low testosterone concentrations after explaining the uncertainties regarding the long-term safety of this treatment. TRT may be offered to men with severe hypogonadism and erectile dysfunction to improve sexual desire, erectile, and orgasmic function. It should also be considered in hypogonadal men with severe insulin resistance or pre-diabetes mellitus. TRT may also be considered, in combination with proven treatment strategies, for osteoporosis, or for selected patients with persistent mild depressive symptoms and/or low self-perceived quality of life, combined with standard medical care for each condition. TRT is contraindicated in hypogonadal men actively seeking fertility treatment. Due to a lack of data, TRT should not be routinely used in older men to improve exercise capacity/physical function, improve cognitive function, or prevent cognitive decline. TRT must be avoided in older, frail men with known breast cancer or untreated prostate cancer and all men who have had myocardial infarction or stroke within the last four months, and those with severe or decompensated heart failure. The quality of evidence regarding patients with previous prostate cancer or cardiovascular disease is too low to draw definitive conclusions. Any limits on duration of use are arbitrary, and treatment should continue for as long as the man feels the benefits outweigh the risks for him, and decisions must be made on an individual basis. Withdrawal should be considered when hypogonadism is reversed after the resolution of underlying disorder. Short-acting transdermal preparations should be preferred for TRT initiation in older men, but injectable forms may be considered subsequently. Older men on TRT should be monitored at 3, 6, and 12months after initiation and at least yearly thereafter, or earlier and more frequently if indicated. Evaluation should include assessment of the clinical response, and measurement of total testosterone, haematocrit, and prostate-specific antigen (PSA) concentrations. Bone density and/or quality should also be assessed. Obese and overweight patients should be encouraged to undergo lifestyle modifications, including exercise and weight loss, to increase endogenous testosterone.

Falsely elevated serum testosterone measurements resulting from testosterone topical gel contamination of the venipuncture site: Case Series and retrospective review

Testosterone as replacement therapy for male hypogonadism or as gender-affirming hormone therapy for transgender and non-binary patients has increased worldwide. Commonly used formulations of testosterone include intramuscular, transdermal patch, and topical gel, each of which has differing pharmacokinetics and practical challenges. In monitoring testosterone serum concentrations, contamination of the phlebotomy site by testosterone topical gel can lead to supraphysiologic (>1000 ng/dL or 34.7 nmol/L) serum concentrations of testosterone, as demonstrated in a few published case reports. The frequency of this issue is currently not known. The present study involves a retrospective search over a 13-year period across all clinical sites at an academic medical center. Out of 578 unique patients using testosterone topical gel, a total of 48 patients had at least 1 testosterone serum concentration exceed 1000 ng/dL. Documentation in the electronic health record revealed 7 patients where contamination of the phlebotomy site by topical gel was strongly supported as the cause of supraphysiologic testosterone serum concentrations. These included 5 males with primary hypogonadism, 1 male with panhypopituitarism, and a non-binary patient with gender dysphoria. The high testosterone concentrations prompted further work-up, including retesting and endocrinology consultation. There were additional cases of high testosterone serum concentration that may have been falsely elevated due to gel contamination but without sufficient supporting evidence available in the health record. Overall, we present 7 cases of spuriously high testosterone concentrations strongly suspected to be due to venipuncture performed near or at the location of prior testosterone gel application. Gel contamination should be considered as a possible cause of otherwise unexplained high testosterone serum concentration in patients receiving topical testosterone gel formulations. Patient counseling and provider awareness of this potential cause of spuriously high testosterone serum concentrations is important.

Men treated with BEACOPP for Hodgkin lymphoma may be at increased risk of testosterone deficiency.

In the current study, we report the prevalence of male testosterone deficiency in a cohort of 60 male long-term survivors of malignant lymphoma with normal total testosterone but in the lower part of the reference level. Testosterone deficiency was defined as subnormal concentrations of total testosterone or subnormal concentrations of calculated free testosterone. The aim was to clarify whether total testosterone was sufficient for identification of testosterone deficiency in male survivors of malignant lymphoma. Hormonal analyses taken at follow-up were compared with samples taken at diagnosis for a subgroup of 20 survivors, for evaluation of changes in hormones over time. Another group of 83 similar survivors of malignant lymphoma with testosterone in the high end of reference levels were also used for comparison, to identify groups of increased risk of testosterone deficiency. A total group of 143 survivors were therefore included in the study. Our findings indicate that for screening purposes an initial total testosterone is sufficient in some survivors because sexual hormone binding globulin concentration was found stable over time. However, 15% were found with subnormal calculated free testosterone. Survivors intensely treated for Hodgkin lymphoma and older survivors were identified as high-risk groups for testosterone deficiency necessitating endocrinological attention during follow-up. Some evidence of pituitary downregulation was also found, because of uncompensated decreases in testosterone concentration over time. In conclusion, longitudinal measurements of total testosterone alone do not seem adequate for the screening of testosterone deficiency for all long-term lymphoma survivors.

Concentration levels of selected hormones in judokas and the extent of their changes during a special performance test at different ambient temperatures

BackgroundThere is little scientific literature available on the diversity of physiological responses of judokas to anaerobic interval exercises in warm environments. Understanding the dynamics of changes in the concentration of selected hormones during a special endurance test at different ambient temperatures may have significant practical value, as it provides an opportunity for optimal programming and monitoring of the training process. So, the main aim of the research was to survey interval anaerobic exercises in different ambient temperatures on Concentration levels of selected hormones in judokas.Methods15 judokas athletes (age: 20.65 ± 2.03 years; body height: 178.00 ± 6.31 cm; body mass: 76.26 ± 12.57 kg; training experience: 12.1 ± 1.57 years) volunteered for the study. The judokas performed five sequences (each lasting 7.20 min) of pulsatile exercises on a cycle ergometer and hand ergometer in a thermoclimatic chamber at temperatures of 21 ± 0.5 °C and 31 ± 0.5 °C. The exercises were different from typical interval exercises, with varying times, upper and lower limb loads, and were followed by a 15-minute break after each sequence. Total duration of the experiment, including the five sequences of pulsating exercise and four 15-minute rest breaks between each exercise sequence, amounted to 96 min and 20 s. The workload was increased by 20 W for the lower limb tests and 12 W for the upper limb tests every 2 min. Biochemical measurements of testosterone (T), cortisol (C), growth hormone (HGH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), adrenaline (E), noradrenaline (NE), and β-endorphin (β-end)were performed using the enzyme-linked immunosorbent assay (ELISA) method on blood samples taken before and after five series of pulsatile exercises, at 1, 24, and 48 h.ResultsPulsatile exercise at ambient temperatures of 21 and 31 °C resulted in a decrease in body weight of the studied athletes (p < 0.05) and significantly reduced body volume and plasma volume after training (p < 0.05). The concentration of HGH, testosterone, cortisol and NE showed a statistically significant difference after the end of the series of pulsating exercises at both temperatures (p < 0.05) and did not significantly affect the concentration of ACTH, FSH and adrenaline concentration.ConclusionsAn increase in the concentration of growth hormone, cortisol and NE was observed after doing the work at both 21 and 31 °C ambient temperature. Physical exertion in both ambient temperatures contributed to a statistically significant decrease in testosterone concentration. Based on the obtained research results, it can be concluded that physical activity in various thermal conditions of the external environment activates the hormonal response to varying degrees, with the direction of changes depending on the external thermal factor.

Relationship between the 2D:4D and prenatal testosterone, adult level testosterone, and testosterone change: Meta-analysis of 54 studies.

The ratio between the hands' second to the fourth finger (2D:4D) is commonly hypothesized to result from prenatal testosterone. The 2D:4D has also been hypothesized to relate to adult-level testosterone and, more recently, to the testosterone response to a challenging situation. In the present work, we tested these core assumptions. Drawing from, in total, 54 studies and 8077 participants, we investigated whether the 2D:4D is related to adult level testosterone (44 studies), testosterone change (6 studies), and prenatal testosterone (10 studies). We found no evidence of the relationship between the above testosterone types and digit ratios. Furthermore, there was no relationship between testosterone and the right and left 2D:4D, male and female 2D:4D, and the 2D:4D and testosterone measurement (i.e., measured in blood or saliva). However, we found some evidence that prenatal testosterone measured in amniotic fluid (but not cord blood) might be related to the digit ratios-further studies are necessary to validate this observation. In summary, considering the current state of knowledge, any conclusions drawn from the assumption of the digit ratios as the proxy for testosterone (prenatal, adult level, or testosterone change under a challenging situation) warrant great caution.

A-048 Accurate Measurement of Free Testosterone in Serum using Equilibrium Dialysis Coupled with ID-UHPLC-MS/MS

Abstract Background Assessment of free testosterone (FT) has been recommended in recent clinical practice guidelines as a biomarker for diagnosis and management of testosterone related disorders such as male testosterone deficiency due to hypogonadism and female androgen excess due to polycystic ovary syndrome (PCOS). FT is currently measured using direct commercial immunoassays, assays using equilibrium dialysis (ED) or other separation techniques. Though the ED approach is recognized as the recommended approach, it is laborious and technically challenging for routine clinical use. The CDC Clinical Standardization Program is developing a high throughput automated method using the ED procedure coupled with isotope dilution ultra-high-performance liquid chromatography tandem mass spectrometry (ID-UHPLC-MS/MS) that is suitable for routine patient care and large-scale epidemiologic studies. Methods Serum samples are dialyzed in a custom-designed multi-well plate against a protein-free HEPES buffer (pH 7.4) at 37 °C until equilibrium. After isolating endogenous FT from protein-bound testosterone by ED, isotope-labeled internal standard (13C3-testosterone) was added to the dialysate for quantification. Certified pure primary reference material (National Measurement Institute-M914) was used to prepare calibrators, enabling traceability and ensuring measurement trueness. FT was further isolated from the dialysate matrix using supported liquid extraction and a chromatographic separation from interfering compounds and quantitation by tandem MS. Results The measurement ranges covered 0.2–1000 ng/dL for testosterone, with the bias within ±5% and precision less than 10% CV. A total of 45 samples with a wide range of total testosterone (TT, 21–912 ng/dL) and SHBG (11–129 nmol/L) were analyzed and showed the suitability of this assay to measure the serum free testosterone levels in normal, hypogonadal males as well as in the majority of normal females and females with androgen excess. The application of 48-well format plate and automated liquid handler system significantly improves the throughput of sample preparation. In addition, comparison of the TT results measured with the presented TT method with calculated TT concentrations, suggest that on average calculation overestimates TT concentration by 34%. Conclusion The described high throughput method for FT allows for sufficiently accurate and precise measurement for routine applications including large epidemiologic studies to help with establishing reference intervals.

A-038 An Improved Multiplexed HTLC-HESI-MSMS Method for the Measurement of Total Testosterone in Serum

Abstract Background Testosterone is an anabolic steroid produced primarily in the testicles of males and mainly in the ovaries of females. Imbalance of testosterone is the primary cause of hypogonadism in males, hirsutism and virilization in females, osteoporosis, and diabetes mellitus. Accurate and fast-turnaround measurement of testosterone is critical for diagnosis, prevention, and treatment of testosterone-related diseases in adults and children. In a previous study, testosterone was derivatized with methoxyamine and hydroxylamine in a multiplexed high turbulence liquid chromatography with heated-electrospray ionization-tandem mass spectrometry (HTLC-HESI-MS/MS) method. Using these reagents, differential mass-tagging of testosterone allowed different specimens to be combined in a single injection to increase assay throughput. However, interference was observed for hydroxylamine-derivatized testosterone in serum collected in serum separator tubes (SST). In the current study, our objectives were to (1) replace hydroxylamine with a new derivatizing agent not subject to interference and (2) develop an improved HTLC-HESI-MS/MS method for multiplexed total testosterone measurement. Methods Healthy male and female donor specimens were collected in SST and red-top tubes. Serum was mixed with stable isotope-labeled testosterone as internal standard (ISTD) prior to protein precipitation. Testosterone in the supernatants was derivatized, enriched by solid phase extraction, dried, and reconstituted. Specimens were injected on the HTLC system for on-line extraction, transferred to analytical columns, and eluted using binary gradient. Testosterone derivatives and ISTDs were detected and analyzed on a Triple Quadrupole Mass Spectrometer (Thermo) equipped with HESI. Ionization and multiple reaction monitoring (MRM) scan parameters were optimized for maximized ion transmission and sensitive, specific, and stable quantitation. MRM transitions were used as quantifiers and qualifiers for both testosterone derivatives. Also assessed were ion suppression using T-column infusion, specimen stability by storage in SST tubes at 4 °C, isobaric interference from dehydroepiandrosterone (DHEA), and carryover. Results Intra- and inter-assay coefficients of variation (CV%) for total testosterone levels were &amp;lt;5% at 12, 80, 250, and 1200 ng/dL for both testosterone derivatives. Limits of quantitation (LOQs) for both derivatives were &amp;lt;1 ng/dL. Calibration linearity was verified across the measurement range of 2.5–2000 ng/dL. Both agents were equivalent in derivatizing and recovering testosterone from serum based on a comparison of their quantitative results (R = 0.991, bias = −3.8 ng/dL). No interference was observed in serum collected in SST. Serum specimens collected in SST and red-top tubes from same donors gave equivalent results (R = 0.991, bias = 0.2 ng/dL). Ion suppression was calculated as less than 20% for both derivatives. CV% of the ion-ratios of both derivatives were less than 15% and were stable across the linear range. Testosterone levels were stable in SST for 72 h (at 4 °C) with the serum not separated from the gel. No isobaric interference and no carry over were observed. Conclusion We have developed and validated an improved multiplexed HTLC-HESI-MS/MS testosterone assay using new derivatizing agents. The current method allowed accurate, rapid, specific, and stable analysis of serum total testosterone. SST is an acceptable specimen type for the current method. Precision, accuracy, linearity, ion suppression, and sample stability in SST were validated.

Retinoic acid loaded with chitosan nanoparticles improves spermatogenesis in scrotal hyperthermia in mice.

High temperatures can trigger cellular oxidative stress and disrupt spermatogenesis, potentially leading to male infertility. We investigated the effects of retinoic acid (RA), chitosan nanoparticles (CHNPs), and retinoic acid loaded with chitosan nanoparticles (RACHNPs) on spermatogenesis in mice induced by scrotal hyperthermia (Hyp). Thirty mice (weighing 25 to 30 g) were divided into five experimental groups of six mice each. The groups were as follows: control, Hyp induced by a water bath (43 °C for 30 minutes/day for 5 weeks), Hyp+RA (2 mg/kg/day), Hyp+CHNPs (2 mg/kg/72 hours), and Hyp+RACHNPs (4 mg/kg/72 hours). The mice were treated for 35 days. After the experimental treatments, the animals were euthanized. Sperm samples were collected for analysis of sperm parameters, and blood serum was isolated for testosterone measurement. Testis samples were also collected for histopathology assessment, reactive oxygen species (ROS) evaluation, and RNA extraction, which was done to compare the expression levels of the bax, bcl2, p53, Fas, and FasL genes among groups. Additionally, immunohistochemical staining was performed. Treatment with RACHNPs significantly increased stereological parameters such as testicular volume, seminiferous tubule length, and testicular cell count. Additionally, it increased testosterone concentration and improved sperm parameters. We observed significant decreases in ROS production and caspase-3 immunostaining in the RACHNP group. Moreover, the expression levels of bax, p53, Fas, and FasL significantly decreased in the groups treated with RACHNPs and RA. RACHNPs can be considered a potent antioxidative and antiapoptotic agent for therapeutic strategies in reproductive and regenerative medicine.

Assessment of exercise-induced stress via automated measurement of salivary cortisol concentrations and the testosterone-to-cortisol ratio: a preliminary study

In this study, our aim was to validate whether the automated measurement of salivary testosterone and cortisol concentrations and the testosterone-to-cortisol (T/C) ratio, considering their individual circadian rhythms can be used to assess the stress response of male athletes to different exercise intensities accurately and effectively. We measured the salivary testosterone and cortisol concentrations and their respective serum concentrations that were collected from 20 male long-distance runners via passive drooling in the morning and evening for two consecutive days involving different exercise intensities. An electrochemiluminescence immunoassay was performed to evaluate the salivary testosterone and cortisol concentrations. The results showed a positive correlation between the salivary testosterone and cortisol concentrations and their respective serum concentrations. The participants were divided into two groups: with and without interval training. The interval training group showed a significantly higher rate of change in the salivary cortisol concentration and a significantly lower rate of change in the T/C ratio in the evening interval training on day 1 than lower-intensity running on day 2. Our results indicated that the salivary cortisol concentrations and the T/C ratio could distinguish between exercises at different intensities, which may be beneficial for detecting differences in stress responses among athletes.

Factors Associated With Circulating Sex Hormones in Men : Individual Participant Data Meta-analyses.

Various factors modulate circulating testosterone in men, affecting interpretation of testosterone measurements. To clarify factors associated with variations in sex hormone concentrations. Systematic literature searches (to July 2019). Prospective cohort studies of community-dwelling men with total testosterone measured using mass spectrometry. Individual participant data (IPD) (9 studies; n= 21 074) and aggregate data (2 studies; n= 4075). Sociodemographic, lifestyle, and health factors and concentrations of total testosterone, sex hormone-binding globulin (SHBG), luteinizing hormone (LH), dihydrotestosterone, and estradiol were extracted. Two-stage random-effects IPD meta-analyses found a nonlinear association of testosterone with age, with negligible change among men aged 17 to 70 years (change per SD increase about the midpoint, -0.27 nmol/L [-7.8 ng/dL] [CI, -0.71 to 0.18 nmol/L {-20.5 to 5.2 ng/dL}]) and decreasing testosterone levels with age for men older than 70 years (-1.55 nmol/L [-44.7 ng/dL] [CI, -2.05 to -1.06 nmol/L {-59.1 to -30.6 ng/dL}]). Testosterone was inversely associated with body mass index (BMI) (change per SD increase, -2.42 nmol/L [-69.7 ng/dL] [CI, -2.70 to -2.13 nmol/L {-77.8 to -61.4 ng/dL}]). Testosterone concentrations were lower for men who were married (mean difference, -0.57 nmol/L [-16.4 ng/dL] [CI, -0.89 to -0.26 nmol/L {-25.6 to -7.5 ng/dL}]); undertook at most 75 minutes of vigorous physical activity per week (-0.51 nmol/L [-14.7 ng/dL] [CI, -0.90 to -0.13 nmol/L {-25.9 to -3.7 ng/dL}]); were former smokers (-0.34 nmol/L [-9.8 ng/dL] [CI, -0.55 to -0.12 nmol/L {-15.9 to -3.5 ng/dL}]); or had hypertension (-0.53 nmol/L [-15.3 ng/dL] [CI, -0.82 to -0.24 nmol/L {-23.6 to -6.9 ng/dL}]), cardiovascular disease (-0.35 nmol/L [-10.1 ng/dL] [CI, -0.55 to -0.15 nmol/L {-15.9 to -4.3 ng/dL}]), cancer (-1.39 nmol/L [-40.1 ng/dL] [CI, -1.79 to -0.99 nmol/L {-51.6 to -28.5 ng/dL}]), or diabetes (-1.43 nmol/L [-41.2 ng/dL] [CI, -1.65 to -1.22 nmol/L {-47.6 to -35.2 ng/dL}]). Sex hormone-binding globulin was directly associated with age and inversely associated with BMI. Luteinizing hormone was directly associated with age in men older than 70 years. Cross-sectional analysis, heterogeneity between studies and in timing of blood sampling, and imputation for missing data. Multiple factors are associated with variation in male testosterone, SHBG, and LH concentrations. Reduced testosterone and increased LH concentrations may indicate impaired testicular function after age 70 years. Interpretation of individual testosterone measurements should account particularly for age older than 70 years, obesity, diabetes, and cancer. Medical Research Future Fund, Government of Western Australia, and Lawley Pharmaceuticals. (PROSPERO: CRD42019139668).

Methods for Evaluating the Efficacy of Medical Castration: A Systematic Review.

Measuring serum testosterone determination during medical castration is recommended by prostate cancer (PCa) guidelines to assess its efficacy and define castration resistance. It has been suggested that other biochemical compounds, such as free testosterone or luteinising hormone (LH), could also assess castration efficacy. We aimed to analyse the current evidence for serum biochemical compounds that could be appropriate candidates for evaluating medical castration efficacy. A systematic review was conducted after two investigators independently searched the literature in the PubMed, Cochrane Library, and EMBASE databases published between January 1980 and February 2023. Their searches used the medical subject headings 'prostatic neoplasms', 'testosterone and androgen antagonists', 'gonadotropin-releasing hormone/analogues and derivatives', 'free testosterone', and 'luteinising hormone'. Studies were selected according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria, and their eligibility was based on the Participants, Intervention, Comparator, and Outcome strategy. The search was limited to original articles published in English. Among the 6599 initially identified titles, 15 original studies analysing the clinical impact of serum testosterone levels in PCa patients undergoing androgen deprivation therapy (ADT) were selected for evidence acquisition. The risk of bias in individual studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. All selected studies used immunoassays to measure serum testosterone, although only methods based on liquid or gas chromatography and mass spectrometry are recommended to measure low testosterone concentrations. The reported series were not uniform in clinical stage, ADT types, and the time or number of serum testosterone measurements. Only some studies found low serum testosterone levels (<20 or <32 ng/dL) associated with greater survival free of biochemical progression and castration resistance. We conclude that little current evidence justifies the measurement of serum testosterone during ADT using no appropriate methods. No reported longitudinal studies have examined the clinical impact of serum testosterone measured using liquid chromatography with tandem mass spectrometry (LC-MSMS), free testosterone, or LH in PCa patients undergoing medical castration. We conclude that well-designed longitudinal studies examining the clinical impact of serum testosterone measured with LC-MSMS, serum-free testosterone, and LH on biochemical progression and castration resistance in PCa patients undergoing neo-adjuvant castration in radiation therapy or continuous castration are needed.

Congenital hypogonadotrophic hypogonadism, induction of minipuberty, and future fertility.

A 33-year-old man with Kallmann syndrome had received pulsatile GnRH as an infant for the treatment of cryptorchidism. As an adult, his treatment for fertility with gonadotrophins was unusually rapid compared with expectations, with a total sperm count of 25 million after only 12 months of gonadotrophin therapy. We propose that pulsatile GnRH treatment as an infant induced minipuberty and facilitated his successful, rapid response to therapy. We also propose that identification of the absence of minipuberty in infants with clinical signs suggesting congenital hypogonadotrophic hypogonadism (CHH) is an opportunity for intervention with pulsatile GnRH yielding benefits for fertility decades later. Absence of minipuberty in males with CHH results in low Sertoli cell numbers and delayed response to induction of spermatogenesis in adulthood. Presentation with 'red flags' for androgen deficiency including cryptorchidism at birth, with or without micropenis, should prompt screening for CHH and minipuberty by measurement of gonadotrophins and testosterone in the first 2 months after birth. Pulsatile GnRH therapy in patients with CHH, given prior to age of attainment of Sertoli cell maturation, can replicate the normal physiology of minipuberty, thereby priming the testis for future fertility.

Effects of Exogenous Human Chorionic Gonadotropin Administration on Plasma Testosterone and Semen Production in the Veiled Chameleon (Chamaeleo calyptratus)

Gamete collection, gamete preservation, hormone analysis, and artificial insemination have become integral parts of in situ and ex situ conservation programs for threatened and endangered species, and while these methods have been used to assist conservation in many different vertebrate groups, limited work has been done in reptiles. For example, semen collection in lizards has only recently been described and determined to be safe. The purpose of this study was to determine effective doses of human chorionic gonadotropin (hCG) for increasing plasma testosterone concentrations in the veiled chameleon (Chamaeleo calyptratus), as well as to determine whether the rise in testosterone impacts semen collection. A cross-over design was used. Chameleons were given injections of 100 IU, 200 IU, and 300 IU of hCG/animal and serial plasma testosterone measurements were collected over 24 hours. 100 IU/animal was determined to increase plasma testosterone concentrations similar to 200 IU, and 300 IU/animal. Following this, we determined weekly injections of hCG (100 IU/animal) would maintain elevated testosterone concentrations over 30 days. Additionally, we determined that elevated testosterone secondary to repeated injections of hCG decreased testicular size as determined by ultrasound. Repeated hCG injections and long-term elevation of plasma testosterone concentrations did not increase the likelihood to collect a semen sample with electroejaculation or improve ejaculate quality. Further research is needed to exogenously stimulate spermatogenesis and increase ejaculate quality to perform timed semen collections in male reptile species.

Baseline endogenous serum testosterone levels and all-cause mortality in men with prostate cancer treated by radical radiotherapy: 11-year follow-up data.

e17003 Background: Low levels of serum testosterone are associated with higher all-cause mortality and cardiovascular mortality in some studies.(PMID: 18040028). But men with low levels of serum testosterone at reduced risk of developing prostate cancer. (PMID: 30077399). In middle-aged and elderly men, single point testosterone measurements have been shown to reliably reflect long term androgen exposure. [PMID: 1548361]. We assessed the interaction of pre-treatment serum testosterone levels and long term all-cause mortality in men with newly diagnosed prostate cancer. Methods: Prostate cancer pts enrolled in an ethics approved, prospective study evaluating a rating scale. Baseline serum testosterone levels were measured before the pts were commenced on androgen deprivation therapy and radical radiotherapy. Patient characteristics: Mean age 68.2yrs (median 69yrs); Age range category &lt; 60yrs:14.9% , 61-70yrs:47.3% and &gt; 71 yrs: 37.8%. Charlson Comorbidity Index (CCI) prevalence at baseline as follows CCI- Low risk : 39.9%; CCI-medium risk : 51.4%; CCI-high risk: 8.8%. PSA median level was 10.85 ug/L. Tumour was localised in a majority of pts- stage T1/T2 in 72% . Pts with M1 disease were not enrolled. Histology grade: Gleeson grade 6 in 7.4% and Gleeson grade 7 in 53.4% . Serum testosterone: Median 11.9 nmol/l; Mean 12.4 (Min-Max 2.6 to 26.7). Cox proportional hazards regression used to analyze the effect of baseline Serum Testosterone on long term overall survival, while controlling for covariates (age, cancer T stage, PSA category, Gleeson Category and Charlson Comorbidity index). Results: Lower levels of serum testosterone at baseline were associated with decreased all-cause mortality. There was no significant correlation between testosterone levels and age in our study sample of relatively elderly population (Pearson Correlation p = 0.362); There was no correlation testosterone levels and PSA levels(P = 0.821); no association between serum Testosterone levels and Gleeson Grade as well as T stage. (F = 0.78 ; P = 0.46 and F = 1.34 ; P = 0.26 respectively). There was also no significant variation in testosterone levels according to Comorbidity categorised by Charlson Comorbidity Index. (F = 1.31 P = 0 .26). Conclusions: Lower Serum testosterone levels were associated with decreased all-cause mortality in this prospectively collected survival data of non-metastatic Prostate cancer patients. [Table: see text]

(303) Patient Satisfaction with Oral Testosterone Undecanoate (Jatenzo) in Men with Previous Testosterone Therapy: An Open-Label Single-Center Phase IV Clinical Trial

Abstract Introduction Testosterone therapy is available in multiple delivery systems such as gels and injections; however, oral formulations have been unavailable in the United States due to hepatotoxicity and variable bioavailability. Oral formulations of testosterone are convenient, easy to use, and avoid the problems of other forms of testosterone therapy. Jatenzo (testosterone undecanoate) is a novel US FDA-approved oral testosterone capsule that provides a uniform response in patients with testosterone deficiency. Objective This study evaluates patient satisfaction with Jatenzo in men with a recent history of alternative testosterone therapy. Methods Patients between 18 and 65 years of age with a diagnosis of testosterone deficiency were recruited. Testosterone deficiency was defined as two measurements of serum total testosterone below 300 ng/dL combined with clinical symptoms in accordance with American Urological Association guidelines. Patients were required to have received previous testosterone therapy and completed an adequate washout period prior to starting Jatenzo. The primary outcomes were patient satisfaction, measured by the Treatment Satisfaction Questionnaire for Medication (TSQM-9); and changes in testosterone deficiency symptoms, measured by the quantitative Androgen Deficiency in Aging Males (qADAM) questionnaire at the 3- and 6-month intervals relative to baseline. Serum testosterone, PSA, hematocrit, and estradiol were also evaluated at each time point. Results Of the 41 patients recruited into the study, 46% had previously received subdermal pellets, 41% intramuscular injections, 6% transdermal gels, and 7% intranasal gels. Total testosterone levels increased from a baseline after appropriate washout from a mean of 187 ng/dL to 773 ng/dL at 1 month, 434 ng/dL at 3 months, and 397 at 6 months of treatment with Jatenzo. Patient satisfaction with Jatenzo as measured by TSQM-9 improved to 52 and 59.3 at the 3-month and 6-month time points, respectively, relative to 38.5 with previous testosterone therapy. Testosterone deficiency symptoms as measured by qADAM were 34 with Jatenzo and 33.5 with previous testosterone therapy. No significant difference was noted in side effects such as polycythemia or changes in estradiol or PSA. Conclusions Jatenzo appears to provide similar patient satisfaction and similar improvement in testosterone deficiency symptoms relative to other forms of testosterone therapy. In addition, Jatenzo increases serum total serum testosterone to reference range (300 – 1000 ng/dL) in &amp;gt;90% of men without a difference in side effect profile. Disclosure Yes, this is sponsored by industry/sponsor: Clarus Therapeutics Clarification Industry funding only - investigator initiated and executed study

Higher testosterone is associated with open-angle glaucoma in women: a genetic predisposition?

BackgroundTestosterone may be a possible modifiable risk factor for open-angle glaucoma (OAG) and intraocular pressure (IOP), but evidence has been scarce and conflicting. In this study we evaluated the association of testosterone and its genetic predisposition with incident (i) OAG, IOP, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GCL +).MethodsParticipants aged 45–100 years were derived from the prospective, population-based Rotterdam Study. Ophthalmic examinations and serum testosterone measurements (including bioavailable and free testosterone) were performed from 1991 onwards. Follow-up took place every 4–5 years. A total of 187 out of 7898 participants were diagnosed with incident (i) OAG during follow-up. Genotyping was performed in 165 glaucoma cases and 6708 controls. We calculated sex-specific weighted genetic risk scores (GRS) for total and bioavailable testosterone. Associations with iOAG were analyzed using multivariable logistic regression. Associations with IOP, RNFL, and GCL + were analyzed with multivariable linear regression. Analyses were stratified on sex and adjusted for at least age, body mass index, and follow-up duration.ResultsIn men, testosterone was not associated with iOAG. However, the GRS for higher total testosterone was associated with an increased iOAG risk (odds ratio [OR] with 95% confidence interval [95% CI]: 2.48 [1.18; 5.22], per unit). In women, higher values of bioavailable testosterone (2.05 [1.00; 4.18] per nmol/L) and free testosterone (1.79 [1.00; 3.20] per ng/dL) were significantly associated with increased risk of iOAG. Moreover, the GRS for higher bioavailable testosterone was associated with an increased iOAG risk (2.48 [1.09; 5.65], per unit). Higher bioavailable and free testosterone were adversely associated with IOP (0.58 [0.05; 1.10] per nmol/L and 0.47 [0.04; 0.90] per ng/dL). Higher total testosterone was inversely associated with peripapillary RNFL and GCL + (Beta [95% CI]: − 3.54 [− 7.02; − 0.06] per nmol/L and − 2.18 [− 4.11; − 0.25] per nmol/L, respectively).ConclusionsIn women, higher testosterone levels increased the risk of iOAG. Both IOP-dependent and IOP-independent mechanisms may underlie this association. Managing testosterone levels may be particularly relevant for the prevention of neurodegeneration in the eye. Future research should confirm these findings.

Effect of iron-enriched bean-based diet on body weight, exercise performance and iron biomarkers in young adult BALB/c mice

Iron deficiency contributes to the global burden of disease, affecting children, premenopausal women, and population from low-income and middle-income countries. To manage the deficit of iron on diet, biofortified crops can be obtained from conventionally plant-based foods. BIO102 bean is a biofortified crop with higher iron and protein content when compared to conventional beans. Therefore, this study aimed to determine the effect of BIO102 food on body weight, exercise performance, and iron biomarkers in young adult BALB/c mice. To achieve this, 24 BALC/c mice were randomly assigned to each of the following groups (n=6 per group): Control diet (conventional diet 5010 Diet; CTRL), bean-based biofortified diet (BIO102), bean-based non-biofortified diet (NB), and corn-based diet (CD). The following parameters were assessed weekly from baseline to 8 weeks: body weight, food intake, endurance capacity, and limbs strength. Baseline blood glucose and hemoglobin measurements were made at the first, three, and eighth weeks of tail blood, and serum ferritin, hepcidin, C-reactive protein, and testosterone measurements were made at the end of 8 weeks of whole blood.During the initial week of housing (acclimatization), there were no differences among groups on neither food intake nor body weight ( p&gt;0.05) (Figure 1). A significant difference in body weight from the second week of feeding with the natural diets was found (Figure 1). Due to signs of stress after three weeks of feeding, all the groups that took the natural diets, received 1 g of 5010Diet food as supplementation up to the end of the experiment. Both CTRL and BIO102 groups showed higher body weight gain when compared to NB and CD groups. Regarding exercise performance, no significant differences were found among groups (Figure 2). As for the iron biomarkers, no differences were determined for hemoglobin concentration and blood glucose in acclimatization (Figure 3). Interestingly, at three weeks, bean-based diet groups were significant different from CTRL group for Blood glucose concentration ( p&lt;0.05) (Figure 3). Moreover, at 8 weeks, only CD group showed a statically significant increase in ferritin (Table 1). In summary, our results suggest that bean-based biofortified diet (BIO102) has a higher nutritional value than common crops such as conventional beans and corn, when compared with a control diet. This suggestion is because the mice feed with BIO102 diet kept body weight gain like those in CTRL group. In addition, BIO102 reduced fasting blood glucose, maintaining both endurance capacity and strength, as well as biomarkers of iron regulation. This work was funded by the following: Pontificia Universidad Javeriana Cali-Colombia, El Centro Internacional de Agricultura Tropical (CIAT) y la Fundación Banco de la República. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effect of Ramadan Fasting on Sex Hormones in Infertile Male

Ramadan fasting is one of the 5 pillars of Islam and one of the most significant Ibadat (worships) of Islam. Throughout the world, millions of Muslims fast during Ramadan to fulfill this religious obligation. Aims: The aim of the study is to determine changes in the serum concentrations of gonadotropins, testosterone and prolactin hormones in infertile males after fasting of Ramadan and whether fasting improves fertility in the male. Participants and Methods: This is a case series study was conducted on 54 infertile male subjects aged (25-50 years) who fasted during Ramadan. Two blood samples were taken from each patient, one before and the other after fasting of Ramadan. Serum FSH, LH, prolactin and testosterone measurement was done by using Enzyme Linked Immune Sorbent Assay (ELISA). Results: There was no significant difference in serum FSH, LH, prolactin hormones when we compared them before and after Ramadan fasting. Concerning serum testosterone hormone, there was a decrease in its level after fasting but not reach significance when compared with its level before fasting. Conclusion: Serum levels of FSH, LH, prolactin and testosterone were unchanged after fasting of Ramadan.

Sex Differences in the Association Between Serum Testosterone and Kidney Function in the General Population

Testosterone might prevent kidney function decline, although evidence is limited in men and lacking in women from the general population. We investigated the association between serum testosterone and kidney function in men and women from a large population-based cohort study. Participants aged≥45 years with available measurements of serum testosterone, sex hormone-binding globulin (SHBG), creatinine, and cystatine C were included. Assessments of kidney function included baseline assessments of the estimated glomerular filtration rate (eGFR) based on serum creatinine (eGFRcreat) or serum cystatin C (eGFRcys), and the urine albumin-to-creatinine ratio (ACR), and repeated assessments of eGFRcreat. Linear regression and linear mixed models were used to assess the associations of serum free and total testosterone with kidney function, stratified for sex. A total of 4095 men and 5389 women (mean age 65.2 years) were included. In men, higher free testosterone was associated with lower eGFRcreat (beta-0.63, 95% confidence interval [CI]:-1.05;-0.21), higher eGFRcys (beta 0.56, 95% CI: 0.07; 1.05), and lower ACR (beta-0.25, 95% CI:-0.35;-0.16) at baseline. Higher total testosterone was associated with higher baseline and follow-up eGFRcreat, and with lower eGFRcreat when additionally adjusted for SHBG. In women, higher free testosterone was associated with lower baseline eGFRcreat and eGFRcys (beta-1.03, 95% CI:-1.36;-0.71; beta-1.07, 95% CI:-1.44;-0.70; respectively) and lower eGFRcreat over time (beta-0.78, 95% CI:-1.10;-0.46), but not with ACR. eGFRcys might be a better parameter than eGFRcreat for the association of testosterone with kidney function, although further studies investigating this are needed. Furthermore, we identified sex differences in the association between testosterone and kidney function, with a positive association in men and a negative association in women.