Serum Testosterone Concentrations Research Articles

Evaluation of male reproductive hormones of Kalahari Red and Kalawad goat bucks as affected by age and season under tropical conditions.

Comprehensive understanding of reproductive hormones and environmental cues with their relationship is essential for efficient production in livestock sectors involving either assisted or natural reproductive methods. This study evaluated the effects of age and seasonal-associated changes in the blood concentrations of testosterone and follicle stimulating hormone (FSH) of male Kalahari Red (KR) andKalawad(KW)-crossbred goats. Based on a 2 × 3 × 4 factorial arrangement, a total of 42 bucks (KR n = 21 and KW n = 21) were allotted into three age groups (> 1 ≤ 2years, > 2 ≤ 3years and > 3 ≤ 4years) with seven KR bucks and seven KW bucks each per age group; reared under different seasons (early rainy, late rainy, early dry and late dry). The animals were managed semi-intensively, kept in an open-ventilated pen and subjected to same nutritional regime throughout the one-year experimental period. Follicle stimulating hormone and testosterone concentrations were analyzed in serum samples. Data obtained reproductive hormones were subjected to three-way Analysis of Variance using SAS 1999. Results show that breed had a significant effect (p < 0.05) on both serum FSH and testosterone concentrations. The highest FSH (0.49 ± 0.02ng/mL, 0.45 ± 0.01ng/mL, 0.41 ± 0.1ng/mL and 0.47 ± 0.07ng/mL) mean values (P > 0.05) were observed in KR in September, October, November and May, respectively while the highest (2.6 ± 0.02ng/mL) testosterone concentration in KW (p < 0.05) was obtained in December. Testosterone had irregular patterns between breeds and months of sampling. FSH was at peak (p > 0.05) in KR during the late rainy season at all ages while the values of FSH concentration in KW were not significantly different at all ages and seasons. The highest (2.05 ± 0.11ng/mL) serum testosterone mean value in KW peaked (p < 0.05) age > 3 ≤ 4years during the late rainy season. Testosterone concentration was lower and steady at all ages during rainy seasons in KR but started fluctuating during the early dry season. The least mean (0.62 ± 0.07ng/mL and 0.68 ± 0.05ng/mL) were recorded (p > 0.05) in KW during the late dry season at age > 2 ≤ 3 and > 3 ≤ 4years respectively. In KR and KW goat breeds raised under tropical condition, the high seasonal variations were responsible for the fluctuations in the reproductive hormones which resultantly altered or lowered the sexual activity of the animals at certain season(s).

Administration of melatonin nanoparticles improves testicular blood flow, echotexture of testicular parenchyma, scrotal circumference, and levels of estradiol and nitric oxide in prepubertal ossimi rams under summer heat stress.

Environmental heat stress (HS) impairs reproductive efficiency in farm animals. This study investigated, for the first time, how the melatonin and melatonin nanoparticles treatment affected the testicular hemodynamics, testicular volume, echotexture [Pixel intensity (PIX) and integrated density (IND)], scrotal circumference, serum concentration of testosterone (T), estradiol (E2), nitric oxide (NO), and total antioxidant capacity (TAC) in prepubertal Ossimi ram lambs in hot climatic conditions. The lambs undergoing examination had a temperature humidity index (THI) of 87.05 ± 1.70, indicating severe HS condition. Fifteen prepubertal Ossimi ram lambs were exposed to a single s.c injection of either nano melatonin (nano melatonin group; 20mg/ram; n = 5) or melatonin suspended in two ml of corn oil (melatonin group; 40mg/ram; n = 5) or two ml of corn oil (control group; n = 5). Blood collection and ultrasonographic assessment of the testes and supratesticular arteries (STAs) were conducted immediately before treatment (W0) and once weekly for six successive weeks after nano melatonin and melatonin injection (W1-W6). Results revealed decreases (P < 0.05) in the Doppler indices (resistive index; RI and pulsatility index; PI) of the testicular arteries at most time points of the study in the nano melatonin and melatonin groups. PIX of testicular parenchyma was significantly increased (P ˂ 0.05) in the treated groups compared to the control one. IND of testicular parenchyma increased significantly in the nano melatonin group compared to the melatonin and control groups. Testicular volume and scrotal circumference significantly increased (P < 0.05) in nano melatonin and melatonin groups compared to the control one. T concentration did not significantly (P > 0.05) change in the treated groups compared to the control group. E2, NO, and TAC concentrations increased (P < 0.05) in the treated groups compared to the control one. In conclusion, this study extrapolated that administrations of melatonin or nano melatonin can ameliorate the effects of environmental HS in prepubertal Ossimi ram lambs with a more protective effect and lower dose of nano melatonin.

Oligoasthenozoospermia is alleviated in a mouse model by [Gly14]-humanin-mediated attenuation of oxidative stress and ferroptosis.

Oligoasthenozoospermia is a common cause of male infertility, for which effective treatments are urgently needed. Humanin (HN) is a peptide associated with this condition. To investigate the ameliorative effect of [Gly14]-Humanin (HNG) on oligoasthenozoospermia and the mechanisms. Mice were treated with cyclophosphamide (CP) to construct a mice model of oligoasthenozoospermia. The resulting model mice were treated with saline or HNG. Subsequently, the testis weights, organ indices, testicular structure, sperm counts and motilities, litter sizes, and serum testosterone concentrations of the mice were determined. Differential gene expression in testicular tissues was determined by RNA sequencing. TM3, TM4, GC1, and GC2 cells were exposed to erastin to induce ferroptosis, followed by treatment with HNG or HNG + ML385 (a nuclear factor erythroid 2-related factor 2 inhibitor). Levels of reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and ferrous ions (Fe2+) were determined and their expression of ferroptosis-related proteins was determined by immunofluorescence and western blot. The HNG treatment improved testis and sperm parameters and increased litter size and serum testosterone concentrations in model mice. Kyoto Encyclopaedia of Genes and Genomes pathway enrichment analysis revealed significant differential expression of ferroptosis-related genes. The expression of ferroptosis-related proteins increased in testicular tissues after the HNG treatment. The concentrations of ROS, MDA, and Fe2+ decreased and the concentrations of GSH increased in testicular tissues and in TM3 and TM4 cells after HNG treatment. In vitro experiments confirmed that HNG activated the nuclear factor erythroid 2-related factor 2/glutathione peroxidase 4 (Nrf2/GPX4) pathway. However, these effects of HNG were blocked by ML385 treatment. HNG demonstrated a therapeutic effect on oligoasthenozoospermia in a mouse model by reducing oxidative stress and ferroptosis. In TM3 and TM4 cells, HNG attenuated cellular oxidative stress and inhibited ferroptosis via the Nrf2/GPX4 pathway.

Spermatogenic and Libido Enhancing Effect of Ethanol Extract of Kigelia Africana in ∆9 Tetrahydrocannabinol Induced Erectile Dysfunction in Male Wistar Rats

Erectile dysfunction has remained one of the major global health issues for the past two decades. Since the discovery of phosphodiesterase type 5 inhibitors, a significant number of patients have solved the issue of erectile dysfunction. However, the wide distribution of phosphodiesterase type 5 enzymes at various sites of the body led phosphodiesterase type 5 inhibitors to cause various unnecessary outcomes. Hence, it is vital to look for optional agents that could solve these limitations. In this present work, erectile dysfunction was induced by administering 30 mg/kgbwt THC for 3 days. Treatment given was as follows: A - Normal Control, B - Std control (THC+Viagra), C - Negative control (THC only), D - THC + 200 mg/Kgbwt ethanol leaf extract of Kigelia africana (200 mg/Kgbwt), E - THC + 400 mg/Kgbwt ethanol leaf extract of Kigelia africana for a succession of 14 days. Sexual behaviour parameters were monitored in the male rats on Days 1, 7 and 14 respectively after administration by pairing with a receptive female (1:1); thereafter, rats were sacrificed and serum was collected for some biochemical parameters using standard method. Cage side observation on the animals revealed prospective behaviours by the receptive female rats and precopulatory behaviours by the ethanol extract K.africana treated male rats.The extract at 200 and 400 mg/kg body weight significantly (P&lt;0.05) increased the frequencies of mount and intromission.In addition, the ejaculation latency was significantly (P&lt; 0.05) prolonged.The latencies of mount and intromission were reduced significantly (P&lt;0.05) whereas ejaculation frequency increased. The extract also reduced the post-ejaculatory interval of the Wistar rats. Computed percentages of index of libido, mounted, intromitted, ejaculated and copulatory efficiency were significantly (p&lt;0.05) higher in the extract-treated animals in a dosage dependent manner than the control whereas the inter copulatory interval decreased significantly. The extract also significantly (p&lt;0.05) increased the serum testosterone, FSH and LH concentration but significantly (p&lt;0.05) reduced serum oestrogen, prolactin and progesterone of the treated groups when compared with the control. The extract also significantly (p&lt;0.05) increased the sperm motility, total sperm count, and sperm viability but produced a significant (p&lt;0.05) decrease in serum immobility when compared with the THC control. It can be inferred from this work that an extract of K. africana may elicit spermatogenic, androgenic and libido enhancing activities in THC induced erectile dysfunction in a dosage dependent manner.

Single-arm study of testosterone gel replacement therapy and ambulatory blood pressure outcomes in men with hypogonadism.

Studies examining ambulatory blood pressure (BP) response to testosterone replacement therapy are needed owing to inconsistent prior findings across formulations. This study assessed testosterone gel 1.62% and 24-h ambulatory BP. Single-arm non-inferiority trial (NCT04274894) conducted at 36 US sites enrolled 246 men with hypogonadism (mean age, 57.6 years; mean office systolic/diastolic BP [SBP/DBP], 129.8/79.5mm Hg) who were treated for 16weeks with once-daily testosterone gel treatment (starting dose, 40.5mg/day; min, max dose, 20.25, 81.0mg/day) to achieve testosterone concentration of 350-750ng/dL. Main outcome measures included mean change in 24-h average SBP (primary endpoint) and DBP from baseline to week 16. The non-inferiority threshold was a two-sided 95% confidence interval (CI) upper limit <3.0mm Hg for 24-h average SBP. Increase in mean±SD serum testosterone concentration to a physiologic level (baseline, 244.4±93.9ng/dL; week 16, 502.5±394.4ng/dL) was associated with a 1.9-mm Hg mean change in 24-h average SBP observed in the primary analysis (baseline, 123.5mm Hg; week 16, 125.4mm Hg; 95% CI, 0.63-3.13mm Hg; n=169). As the upper CI limit modestly exceeded the non-inferiority margin (3mm Hg), study drug effect on SBP could not be ruled out. Non-inferiority was observed in subgroups without hypertension or diabetes (95% CI, upper limit <3.0mm Hg) and was not observed in those with hypertension or diabetes. Daytime SBP and DBP changes were larger compared with nighttime. No clear cardiovascular adverse events or new safety signals were identified. While the effect of testosterone gel 1.62% on 24-h average SBP could not be ruled out based on the study's non-inferiority margin, the clinical relevance of the small-magnitude mean increase of 1.9mm Hg is anticipated to be minimal considering the results of the TRAVERSE study of testosterone gel 1.62% and major adverse cardiac events. ClinicalTrials.gov identifier: NCT04274894 (registered February 17, 2020).

Development of KISS1 knockout pigs is characterized by hypogonadotropic hypogonadism, normal growth, and reduced skatole.

Kisspeptin is a major regulator of gonadotropin secretion in pigs. Previously, CRISPR/Cas9 knockout of KISS1 was used to develop a mosaic parental line of pigs to generate offspring that would not need castration due to loss of kisspeptin. The current goal was to characterize growth and reproductive development of F1 pigs from this parental line. Body weights, gonadotropin concentrations and gonadal development were measured from birth through development (boars to 220 d of age, n = 42; gilts to 160 d of age, n = 36). Testosterone, skatole, and androstenone were also measured in boars. Blood samples were collected by jugular venipuncture for quantification of serum hormones, gonadal tissues collected for gross morphology and histology, and a fat biopsy collected (boars) for skatole and androstenone analysis. Body weight did not differ with genotype. There were no differences between KISS1+/+ and heterozygote KISS1+/- animals for most parameters measured. Gonadotropin concentrations were reduced in KISS1-/- boars and gilts compared with KISS1+/+ and KISS1+/- animals (P < 0.05). Concentrations of testosterone in serum and both androstenone and skatole in adipose were less in KISS1-/- boars than in KISS1+/+ and KISS1+/- boars (P < 0.05). Hypogonadism was in all KISS1-/- gilts and boars. These data indicate that knocking out KISS1 causes hypogonadotropic hypogonadism but does not negatively affect growth in pigs. Only one KISS1 allele is needed for normal gonadotropin secretion and gonadal development, and accumulation of compounds in adipose leading to boar taint.

9240 Role Of Genetics In The Age-Related Testosterone Decline In Men: A UK Biobank Study

Abstract Disclosure: L. Ogoniak: None. S. Sandmann: None. J. Varghese: None. A.S. Busch: None. Background: Age-related decline in circulating serum testosterone concentrations is a well-established phenomenon in men. While the decline is partially linked to comorbidities such as obesity, type 2 diabetes (T2D), and cardiovascular disease (CVD), healthy ageing men present with rather stable levels. Recent genetic mapping studies demonstrated a large influence of common genetic variation on testosterone levels in men. However, increasing incidence rates of comorbidities in the ageing population are posing a challenge for the disentanglement of effects. Objective: Our study aims to investigate the genetic component of age-dependent testosterone decline in men. We hypothesize that the decline in testosterone levels in ageing men is primarily influenced by comorbidities, without significant alterations in the genetic architecture of testosterone levels. Material and Methods: We included 6,406 men with baseline and follow-up measurements of circulating serum concentrations of total testosterone (T), bioavailable testosterone (BAT) and sex hormone-binding globulin (SHBG) representing an independent sub-cohort of the UK Biobank study. We 1) assessed the association of baseline levels with the decline in sex steroids and 2) developed and verified polygenic risk score (PRS) models for T, BAT and SHBG based on 183,909 men from the UK Biobank (sub cohorts: 70% base, 15% target and 15% validation, follow-up cohort excluded for PRS development). Results: In the follow-up sub cohort, mean age (SD) at baseline was 58.2 yrs ( 7.5) and mean (SD) follow-up period was 4.3 (1.0) yrs. Mean (SD) BAT at baseline were 5.2 (1.32) nmol/L with a mean (SD) decline of 1.6 (24.4) % at follow-up. Baseline BAT, T and SHBG levels were significantly associated with the relative change of the respective biomarker at follow-up (-7.8, -2.9 and -0.4% per nmol/L, respectively, all p &amp;lt;0.001). After correcting for age at baseline, follow-up period and principal components 1-10, PGSTestosterone and PGSBAT were not associated with relative decline of the respective biomarker (both p = n.s.). Conclusion: Our study did not find evidence supporting a genetic component in the age-related decline of circulating serum T or BAT concentrations. Instead, in accordance to previous observational studies, our results suggest that rather non-genetic factors, e.g. increasing incidence rates of comorbidities, drive the age-related decline in sex steroid levels in men. Our study contributes to understanding the intricate relationship between genetic and non-genetic factors with age-related testosterone decline in men and offers valuable insights for potential interventions targeting age-related hormonal changes and associated health outcomes. Presentation: 6/2/2024

8039 Role Of Genetics In The Age-Related Testosterone Decline In Men: A UK Biobank Study

Abstract Disclosure: L. Ogoniak: None. S. Sandmann: None. J. Varghese: None. A.S. Busch: None. Background: Age-related decline in circulating serum testosterone concentrations is a well-established phenomenon in men. While the decline is partially linked to comorbidities such as obesity, type 2 diabetes (T2D), and cardiovascular disease (CVD), healthy ageing men present with rather stable levels. Recent genetic mapping studies demonstrated a large influence of common genetic variation on testosterone levels in men. However, increasing incidence rates of comorbidities in the ageing population are posing a challenge for the disentanglement of effects. Objective: Our study aims to investigate the genetic component of age-dependent testosterone decline in men. We hypothesize that the decline in testosterone levels in ageing men is primarily influenced by comorbidities, without significant alterations in the genetic architecture of testosterone levels. Material and Methods: We included 6,406 men with baseline and follow-up measurements of circulating serum concentrations of total testosterone (T), bioavailable testosterone (BAT) and sex hormone-binding globulin (SHBG) representing an independent sub-cohort of the UK Biobank study. We 1) assessed the association of baseline levels with the decline in sex steroids and 2) developed and verified polygenic risk score (PRS) models for T, BAT and SHBG based on 183,909 men from the UK Biobank (sub cohorts: 70% base, 15% target and 15% validation, follow-up cohort excluded for PRS development). Results: In the follow-up sub cohort, mean age (SD) at baseline was 58.2 yrs ( 7.5) and mean (SD) follow-up period was 4.3 (1.0) yrs. Mean (SD) BAT at baseline were 5.2 (1.32) nmol/L with a mean (SD) decline of 1.6 (24.4) % at follow-up. Baseline BAT, T and SHBG levels were significantly associated with the relative change of the respective biomarker at follow-up (-7.8, -2.9 and -0.4% per nmol/L, respectively, all p &amp;lt;0.001). After correcting for age at baseline, follow-up period and principal components 1-10, PGSTestosterone and PGSBAT were not associated with relative decline of the respective biomarker (both p = n.s.). Conclusion: Our study did not find evidence supporting a genetic component in the age-related decline of circulating serum T or BAT concentrations. Instead, in accordance to previous observational studies, our results suggest that rather non-genetic factors, e.g. increasing incidence rates of comorbidities, drive the age-related decline in sex steroid levels in men. Our study contributes to understanding the intricate relationship between genetic and non-genetic factors with age-related testosterone decline in men and offers valuable insights for potential interventions targeting age-related hormonal changes and associated health outcomes. Presentation: 6/2/2024

9240 Role Of Genetics In The Age-Related Testosterone Decline In Men: A UK Biobank Study

Abstract Disclosure: L. Ogoniak: None. S. Sandmann: None. J. Varghese: None. A.S. Busch: None. Background: Age-related decline in circulating serum testosterone concentrations is a well-established phenomenon in men. While the decline is partially linked to comorbidities such as obesity, type 2 diabetes (T2D), and cardiovascular disease (CVD), healthy ageing men present with rather stable levels. Recent genetic mapping studies demonstrated a large influence of common genetic variation on testosterone levels in men. However, increasing incidence rates of comorbidities in the ageing population are posing a challenge for the disentanglement of effects. Objective: Our study aims to investigate the genetic component of age-dependent testosterone decline in men. We hypothesize that the decline in testosterone levels in ageing men is primarily influenced by comorbidities, without significant alterations in the genetic architecture of testosterone levels. Material and Methods: We included 6,406 men with baseline and follow-up measurements of circulating serum concentrations of total testosterone (T), bioavailable testosterone (BAT) and sex hormone-binding globulin (SHBG) representing an independent sub-cohort of the UK Biobank study. We 1) assessed the association of baseline levels with the decline in sex steroids and 2) developed and verified polygenic risk score (PRS) models for T, BAT and SHBG based on 183,909 men from the UK Biobank (sub cohorts: 70% base, 15% target and 15% validation, follow-up cohort excluded for PRS development). Results: In the follow-up sub cohort, mean age (SD) at baseline was 58.2 yrs ( 7.5) and mean (SD) follow-up period was 4.3 (1.0) yrs. Mean (SD) BAT at baseline were 5.2 (1.32) nmol/L with a mean (SD) decline of 1.6 (24.4) % at follow-up. Baseline BAT, T and SHBG levels were significantly associated with the relative change of the respective biomarker at follow-up (-7.8, -2.9 and -0.4% per nmol/L, respectively, all p &amp;lt;0.001). After correcting for age at baseline, follow-up period and principal components 1-10, PGSTestosterone and PGSBAT were not associated with relative decline of the respective biomarker (both p = n.s.). Conclusion: Our study did not find evidence supporting a genetic component in the age-related decline of circulating serum T or BAT concentrations. Instead, in accordance to previous observational studies, our results suggest that rather non-genetic factors, e.g. increasing incidence rates of comorbidities, drive the age-related decline in sex steroid levels in men. Our study contributes to understanding the intricate relationship between genetic and non-genetic factors with age-related testosterone decline in men and offers valuable insights for potential interventions targeting age-related hormonal changes and associated health outcomes. Presentation: 6/2/2024

8039 Role Of Genetics In The Age-Related Testosterone Decline In Men: A UK Biobank Study

Abstract Disclosure: L. Ogoniak: None. S. Sandmann: None. J. Varghese: None. A.S. Busch: None. Background: Age-related decline in circulating serum testosterone concentrations is a well-established phenomenon in men. While the decline is partially linked to comorbidities such as obesity, type 2 diabetes (T2D), and cardiovascular disease (CVD), healthy ageing men present with rather stable levels. Recent genetic mapping studies demonstrated a large influence of common genetic variation on testosterone levels in men. However, increasing incidence rates of comorbidities in the ageing population are posing a challenge for the disentanglement of effects. Objective: Our study aims to investigate the genetic component of age-dependent testosterone decline in men. We hypothesize that the decline in testosterone levels in ageing men is primarily influenced by comorbidities, without significant alterations in the genetic architecture of testosterone levels. Material and Methods: We included 6,406 men with baseline and follow-up measurements of circulating serum concentrations of total testosterone (T), bioavailable testosterone (BAT) and sex hormone-binding globulin (SHBG) representing an independent sub-cohort of the UK Biobank study. We 1) assessed the association of baseline levels with the decline in sex steroids and 2) developed and verified polygenic risk score (PRS) models for T, BAT and SHBG based on 183,909 men from the UK Biobank (sub cohorts: 70% base, 15% target and 15% validation, follow-up cohort excluded for PRS development). Results: In the follow-up sub cohort, mean age (SD) at baseline was 58.2 yrs ( 7.5) and mean (SD) follow-up period was 4.3 (1.0) yrs. Mean (SD) BAT at baseline were 5.2 (1.32) nmol/L with a mean (SD) decline of 1.6 (24.4) % at follow-up. Baseline BAT, T and SHBG levels were significantly associated with the relative change of the respective biomarker at follow-up (-7.8, -2.9 and -0.4% per nmol/L, respectively, all p &amp;lt;0.001). After correcting for age at baseline, follow-up period and principal components 1-10, PGSTestosterone and PGSBAT were not associated with relative decline of the respective biomarker (both p = n.s.). Conclusion: Our study did not find evidence supporting a genetic component in the age-related decline of circulating serum T or BAT concentrations. Instead, in accordance to previous observational studies, our results suggest that rather non-genetic factors, e.g. increasing incidence rates of comorbidities, drive the age-related decline in sex steroid levels in men. Our study contributes to understanding the intricate relationship between genetic and non-genetic factors with age-related testosterone decline in men and offers valuable insights for potential interventions targeting age-related hormonal changes and associated health outcomes. Presentation: 6/2/2024

6979 Effect of Orchiectomy on Muscle Growth and Differentiation Factors in Male Mice With Kidney Disease

Abstract Disclosure: O. Marks: None. J. Bruno: None. D. Wu: None. A. Patwardhan: None. Y. Komaru: None. G. Ling: None. E. Kefalogianni: None. R. Aurora: None. S.S. Dhindsa: None. A. Herrlich: None. Background: Sarcopenia and frailty are major clinical concerns in participants with chronic kidney disease (CKD). In males, an additional factor contributes to the development of sarcopenia. Around half of the men with CKD have subnormal serum testosterone (T) concentrations. The mechanisms that underlie the effect of low T concentrations on muscle growth in CKD are not known. In this study, we performed orchiectomy in male mice with kidney disease and evaluated the expression and protein content of the following muscle growth and differentiation factors. Methods: Forty mice were divided into 4 groups: 1) renal injury, induced by ischemia-induced reperfusion (IRI, N=11) at 2 months of age; 2) orchidectomy (ORX), performed 4 weeks after IRI (IRI + ORX, N=9); 3) sham-IRI and ORX (sham-ORX, N=8); and 4) sham-sham surgery (N=12). The mice were sacrificed when they were ∼7 months old (mean age 206±13 days). Gastrocnemius and levator ani muscles were harvested to measure expression by RT-qPCR of muscle catabolism markers (Atrogin-1 and ubiquitin ligase MuRF1), muscle growth inhibitors, myostatin and myogenic regulatory factor (Mrf4), fibroblast growth factor-2 (FGF2, a stimulator of satellite stem cells) and its receptor FGFR2, androgen receptor (AR) and IGF-1. Results: The mean BUN (blood urea nitrogen) at the time of sacrifice was higher in the IRI/ORX (32±4 mg/dl) and IRI/Sham (26±5 mg/dl) groups as compared to sham-sham (21±5 mg/dl, p&amp;lt;0.05 for both). There was a significant reduction (p&amp;lt;0.05) in the expression of myostatin (by 41%), Mrf4 (29%), atrogin-1 (51%) and MuRF1 (32%) in gastrocnemius muscle from the ORX-IRI and ORX-sham groups, while there was no difference in FGF2 and FGFR2, as compared to sham-sham group. Data from levator ani muscle (the most androgen sensitive muscle in mammals) showed increases in AR (64%) and Atrogin-1 (66%); and decreases in IGF-1 (88%) and myostatin (86%) in ORX-IRI and ORX-sham groups. Consistent with the mRNA expression, we found a drastic decline in protein content of myostatin in gastrocnemius (85%) in ORX-IRI and ORX-sham groups as compared to sham-sham (p=0.04). Conclusions: These data show that ORX in mice with renal injury is associated with changes in muscle growth and differentiation factors. Myostatin was the most affected gene, with 41-86% decline in mRNA and protein. These data are informative for attempts to develop treatments for sarcopenia in patients with kidney disease. Limitations: Our experimental model differs in some respects from hypogonadal men with CKD. ORX results in complete elimination of T, and thus much lower T concentrations than in men with kidney disease. There is a recovery of kidney function after IRI. We sacrificed the mice 5 months after renal injury was inflicted. Hence, the effect of IRI on muscle growth genes may have been different immediately following IRI. Thus, the impact of ORX was more apparent than of IRI in our study. Presentation: 6/1/2024

6979 Effect of Orchiectomy on Muscle Growth and Differentiation Factors in Male Mice With Kidney Disease

Abstract Disclosure: O. Marks: None. J. Bruno: None. D. Wu: None. A. Patwardhan: None. Y. Komaru: None. G. Ling: None. E. Kefalogianni: None. R. Aurora: None. S.S. Dhindsa: None. A. Herrlich: None. Background: Sarcopenia and frailty are major clinical concerns in participants with chronic kidney disease (CKD). In males, an additional factor contributes to the development of sarcopenia. Around half of the men with CKD have subnormal serum testosterone (T) concentrations. The mechanisms that underlie the effect of low T concentrations on muscle growth in CKD are not known. In this study, we performed orchiectomy in male mice with kidney disease and evaluated the expression and protein content of the following muscle growth and differentiation factors. Methods: Forty mice were divided into 4 groups: 1) renal injury, induced by ischemia-induced reperfusion (IRI, N=11) at 2 months of age; 2) orchidectomy (ORX), performed 4 weeks after IRI (IRI + ORX, N=9); 3) sham-IRI and ORX (sham-ORX, N=8); and 4) sham-sham surgery (N=12). The mice were sacrificed when they were ∼7 months old (mean age 206±13 days). Gastrocnemius and levator ani muscles were harvested to measure expression by RT-qPCR of muscle catabolism markers (Atrogin-1 and ubiquitin ligase MuRF1), muscle growth inhibitors, myostatin and myogenic regulatory factor (Mrf4), fibroblast growth factor-2 (FGF2, a stimulator of satellite stem cells) and its receptor FGFR2, androgen receptor (AR) and IGF-1. Results: The mean BUN (blood urea nitrogen) at the time of sacrifice was higher in the IRI/ORX (32±4 mg/dl) and IRI/Sham (26±5 mg/dl) groups as compared to sham-sham (21±5 mg/dl, p&amp;lt;0.05 for both). There was a significant reduction (p&amp;lt;0.05) in the expression of myostatin (by 41%), Mrf4 (29%), atrogin-1 (51%) and MuRF1 (32%) in gastrocnemius muscle from the ORX-IRI and ORX-sham groups, while there was no difference in FGF2 and FGFR2, as compared to sham-sham group. Data from levator ani muscle (the most androgen sensitive muscle in mammals) showed increases in AR (64%) and Atrogin-1 (66%); and decreases in IGF-1 (88%) and myostatin (86%) in ORX-IRI and ORX-sham groups. Consistent with the mRNA expression, we found a drastic decline in protein content of myostatin in gastrocnemius (85%) in ORX-IRI and ORX-sham groups as compared to sham-sham (p=0.04). Conclusions: These data show that ORX in mice with renal injury is associated with changes in muscle growth and differentiation factors. Myostatin was the most affected gene, with 41-86% decline in mRNA and protein. These data are informative for attempts to develop treatments for sarcopenia in patients with kidney disease. Limitations: Our experimental model differs in some respects from hypogonadal men with CKD. ORX results in complete elimination of T, and thus much lower T concentrations than in men with kidney disease. There is a recovery of kidney function after IRI. We sacrificed the mice 5 months after renal injury was inflicted. Hence, the effect of IRI on muscle growth genes may have been different immediately following IRI. Thus, the impact of ORX was more apparent than of IRI in our study. Presentation: 6/1/2024

6597 An Unusual Case of Klinefelter Syndrome with Both Primary and Superimposed Secondary Hypogonadism

Abstract Disclosure: A. Krueger: None. E. Pelley: None. Introduction: Klinefelter syndrome (KS) (47, XXY) is a sex-chromosome disorder that is a common cause of infertility and hypogonadism in men. Clinical phenotype includes tall stature, delayed or incomplete puberty, small testes (&amp;lt;4ml), gynecomastia, and oligo or azoospermia. The extra X chromosome leads to fibrosis and hyalinization of seminiferous tubules resulting in impaired sperm production. Leydig cells also function abnormally and fail to stimulate with LH. Common biochemical evaluation results in low serum testosterone, elevated FSH and LH concentrations, and azoospermia. Case Report: 37-year-old male presented with long standing history of low libido and a perception that he had never fully progressed through puberty. Physical exam was notable for a height of 6’ 4”, obesity, fine pubic and axillary hair, and testes &amp;lt;4mL bilaterally. Initial biochemical work up revealed low serum total testosterone 43 (ref 300-1080 ng/dL), low free testosterone 8.1 (ref 47-244 pg/mL), inappropriately normal LH 10.8 (ref 0.6-12.1 mlU/mL), and elevated FSH 28.3 (ref 1.0-12.0 mlU/mL). Patient was referred to Endocrinology. Labs were repeated with consistent results in addition to chromosome analysis which confirmed diagnosis of Klinefelter syndrome with (47, XXY) karyotype. Due to inappropriately normal LH and mixed picture of primary and superimposed secondary hypogonadism, an MRI of the pituitary was obtained and revealed an 8mm x7mm x 14mm pituitary macroadenoma. Evaluation for pituitary hypersecretion and other deficiencies was unremarkable. Conclusion: Data from the Danish National registry shows that only 25% of Klinefelter patients are correctly diagnosed. Klinefelter syndrome should be considered in the differential for the evaluation of hypogonadism and infertility. Diagnosis can be made by karyotyping. The degree of impaired spermatogenesis and testosterone production in Klinefelter syndrome can be variable. Biochemical evaluation should be interpreted in conjunction with clinical context. Patients with known causes of primary hypogonadism who demonstrate an inappropriate gonadotropin response require evaluation for causes of secondary hypogonadism. In this case, the inappropriately normal LH was the sole clue leading to the identification of his pituitary macroadenoma. Presentation: 6/1/2024

7500 Effect Of Orchiectomy On Bone Microarchitecture In Male Mice With Kidney Disease

Abstract Disclosure: D. Wu: None. A. Patwardhan: None. O. Marks: None. Y. Komaru: None. E. Kefalogianni: None. R. Aurora: None. S. Dhindsa: None. A. Herrlich: None. Background: Chronic kidney disease (CKD) leads to decreased bone density and increased fracture risk. In males, an additional factor contributes to the low bone density. Around half of the men with CKD have low serum testosterone concentrations. We hypothesized that CKD and low testosterone would have an additive and detrimental effect on bone. Methods: Forty male C57BL/6 mice were divided into 4 groups: 1) renal injury, induced by ischemia-induced reperfusion (IRI) and sham orchidectomy (IRI-sham, N=8) at 2 months of age; 2) orchidectomy (ORX), performed 4 weeks after IRI (IRI + ORX, N=11); 3) sham-ORX, N=9; and 4) sham-sham surgery, N=12. 12 weeks after IRI, the mice developed renal fibrosis and decreased glomerular filtration rate, indicative of CKD. The mice were sacrificed when they were 7 months old. Femur and tibia were harvested for both histology and μCT analysis. Results: Bone volume to total volume fraction (BV/TV) was lower in the IRI-ORX (0.06±0.02) and sham-ORX (0.08±0.02), as compared to IRI-sham (0.10±0.03, p&amp;lt;0.05) and sham-sham group (0.14±0.03, p&amp;lt;0.05) respectively. Similarly, the volumetric bone mineral density (vBMD) in IRI-ORX (93±27 mgHA/cm3) and sham-ORX (112±39 mgHA/cm3) groups were lower than IRI-sham (150±43 mgHA/cm3, p&amp;lt;0.05) and sham-sham (187±30 mgHA/cm3, p&amp;lt;0.05) mice. Trabecular number (Tb.N) was decreased in the IRI-ORX group (2.7±0.7 #/mm) compared to IRI-sham group (4.1±1.1 #/mm, p&amp;lt;0.05). Tb.N was also lower in sham-ORX (3.2±1.1 #/mm) mice than sham-sham (4.5±0.2 #/mm), but not IRI-sham mice. In contrast, trabecular thickness (Tb.Th) was lower in IRI-ORX (0.035±0.002 mm) and IRI-sham (0.038±0.002 mm) compared to sham-ORX (0.045±0.005 mm) and sham-sham (0.047±0.005 mm, p&amp;lt;0.05). Trabecular spacing (Tb.Sp) was increased by 47% in IRI-ORX group compared to IRI-sham group (0.26±0.09 mm). Decreased trabecular numbers and increased spacing results in reduced connectivity density (Conn.Den), which was decreased by 60% in the IRI-ORX sham-ORX groups as compared to sham-sham group (423±58 #/mm3, p&amp;lt;0.05). 2 way ANOVA analysis showed that ORX significantly contributed to the variance in BV/TV (p&amp;lt;0.001), vBMD (p&amp;lt;0.001), Tb.N (p&amp;lt;0.01), Tb.Sp (p&amp;lt;0.01) and Conn.Den (p&amp;lt;0.001), while IRI contributed to Tb.Th (p&amp;lt;0.0001). There was no significant interaction between IRI and ORX in all endpoints. Conclusions: Taken together, these data indicate that even in the presence of established CKD, ORX has a greater effect on bone mass. ORX decreased trabecular number (Tb.N) and increased trabecular spacing (Tb.Sp) to a greater extent than IRI. IRI decreased trabecular thickness (Tb.Th) while ORX had no effect on that parameter. Trabecular bone loss starts by trabecular thinning. Eventually, the trabeculae will be completely resorbed, resulting in decreased trabecular numbers and increased spacing. Our data indicate that IRI and ORX affect bone at different time points. Presentation: 6/1/2024

Berberine alters the gut microbiota metabolism and impairs spermatogenesis.

Berberine (BBR) is used to treat diarrhea clinically. However, its reproductive toxicity is unclear. This study aims to investigate the impact of BBR on the male reproductive system. Intragastric BBR administration for 14 consecutive days results in a significant decrease in the serum testosterone concentration, epididymal sperm concentration, mating rate and fecundity of male mice. Testicular treatment with testosterone propionate (TP) partially reverses the damage caused by BBR to the male reproductive system. Mechanistically, the decrease in Muribaculaceae abundance in the gut microbiota of mice is the principal cause of the BBR-induced decrease in the sperm concentration. Both fecal microbiota transplantation (FMT) and polyethylene glycol (PEG) treatment demonstrate that Muribaculaceae is necessary for spermatogenesis. The intragastric administration of Muribaculaceae intestinale to BBR-treated mice restores the sperm concentration and testosterone levels. Metabolomic analysis reveals that BBR affects arginine and proline metabolism, of which ornithine level is downregulated. Combined analysis via 16S rRNA metagenomics sequencing and metabolomics shows that Muribaculaceae regulates ornithine level. The transcriptomic results of the testes indicate that the expressions of genes related to the low-density lipoprotein receptor (LDLR)-mediated testosterone synthesis pathway decrease after BBR administration. The transcriptional activity of the Ldlr gene in TM3 cells is increased with increased ornithine supplementation in the culture media, leading to increased testosterone synthesis. Overall, this study reveals an association between a BBR-induced decrease in Muribaculaceae abundance and defective spermatogenesis, providing a prospective therapeutic approach for addressing infertility-related decreases in serum testosterone triggered by changes in the gut microbiota composition.

Preparation and in vitro/in vivo evaluation of uniform-sized Goserelin-loaded sustained release microspheres

Sustained release microspheres loaded with goserelin are regarded as a promising candidate for treating prostate cancer and other sex hormone diseases. However, their widespread adoption has been hindered by issues such as wide particle size distribution and unstable release characteristics. To address these challenges, we employed a combination of the solid-in-oil-in-water microspheres preparation approach (S/O/W) and innovative premix membrane emulsification technology and deeply investigated the effects of four key parameters on the loaded performance of microspheres and the microscopic mechanisms behind them. With this approach, we successfully produced goserelin-loaded sustained release microspheres of narrow particle size distribution (Span 0.642), remarkable encapsulation efficiency (DL = 4.23 %, EE = 93.98 %), low initial burst release (about 0.50 % within 2 h), and compatibility with small injection needles (23-G, inner diameter 0.33 mm, outer diameter 0.64 mm, maximal force 59 N). In the animal model(administered dose, 2.4 mg·Kg−1), goserelin long-acting sustained release microspheres sustained release for over 32 days, maintaining effective concentrations above 2 ng·mL−1, and effectively reduced serum testosterone concentrations to castration levels (<1.0 ng·mL−1) by day 4, maintaining this inhibition for up to 21 days, exhibiting comparable efficacy to the positive control group. In vivo release kinetics analysis revealed that goserelin-loaded sustained release microspheres exhibited a release pattern dominated by diffusion with corrosion assistance in vivo. In summary, the systematic and comprehensive evaluation of uniform-sized goserelin-loaded sustained release microspheres has highlighted their excellent translational potential, and the study herein may provide new strategies and ideas for the development of microsphere dosage forms.

Androgen Exhibits a Protective Role Against Focal Erosions in Murine TNF-induced Inflammatory Arthritis.

Rheumatoid arthritis (RA) is characterized by erosive pathology associated with joint inflammation and a sexual dimorphism with increased prevalence in females. Here, we aim to determine whether androgen is protective against inflammatory-erosive disease in TNF-transgenic (TNF-Tg) mice. Wild-type (WT) and TNF-Tg male mice underwent sham (WT, n = 3; TNF-Tg, n = 7) or orchiectomy (WT, n = 3; TNF-Tg, n = 7) surgery at 1 month old to remove androgen production confirmed by serum testosterone concentration. Cohorts of orchiectomized TNF-Tg males were treated with either 5ɑ-dihydrotestosterone (.025 mg/day) (n = 3) or placebo (n = 3) via subcutaneous pellet insertion. Weekly clinical measures, along with mid-hindpaw bone volumes and ankle histology at 3 months old were evaluated for all groups. Orchiectomies in TNF-Tg males significantly decreased serum testosterone (P < .05), weight gain (P < .001), and mid-hindpaw bone volumes (P < .05) in comparison to sham TNF-Tg mice. The cuboid bone also had increased synovitis by histology with the loss of androgen (P < .05). Treatment of orchiectomized TNF-Tg males with 5ɑ-dihydrotestosterone protected against the changes in weight gain (P < .01) and bone erosion (P < .05) associated with decreased osteoclast number in the cuboid (P < .01). In the TNF-Tg model of chronic inflammatory arthritis, androgen is protective in erosive disease. The loss of endogenous androgen significantly accelerated the progression of inflammatory-erosive arthritis in male TNF-Tg mice to a similar severity as age-matched female mice. In addition, treatment with exogenous androgen prevented this observed bone loss in orchiectomized TNF-Tg males. Overall, androgen delays and limits bone erosion even in the presence of active inflammation and future studies are warranted to elucidate the associated mechanisms.

Improving the Determination of Carbon Isotope Ratios of Endogenous Steroids Found in Human Serum.

The determination of serum concentrations of testosterone (T) and 4-androstenedione (A4) was implemented into the steroidal module of the Athlete Biological Passport in 2023. Monitoring T, A4, and the ratio of T/A4 in a longitudinal manner enables the detection of the misuse of low-dose T administrations especially in female athletes, whereas urinary markers of the steroid profile may not be influenced significantly. In contrast to the urinary steroid profile, knowledge on confounding factors regarding serum concentrations of T and A4 is yet comparably scarce, and corroborating exogenous sources of the target analytes by isotope ratio mass spectrometry (IRMS) is desirable. In a recent study, it was demonstrated that carbon isotope ratios (CIRs) of serum steroids can be determined if analyte concentrations permit. The therein-employed method utilized 2D-GC/IRMS, and only a limited number of potential endogenous reference compounds were available. The here-presented approach uses complementary analyte purification strategies, addressing previous limitations. A high-performance liquid chromatography cleanup was developed and fully validated for serum steroids in order to enable all doping control laboratories to potentially implement this method alongside existing protocols for urinary steroids. Besides the already-investigated endogenous steroids cholesterol, dehydroepiandrosterone sulfate, androsterone sulfate, and epiandrosterone sulfate, two additional steroids were included in the test menu, namely, pregnenolone sulfate and 5-androstene-3β,17β-diol sulfate. Serum steroid concentrations down to 25 ng/mL were found to allow robust CIR determinations, and a reference population encompassing 124 male and female athlete samples was investigated to enable the calculation of population-based thresholds for all relevant steroid combinations.

Safety, efficacy, and pharmacokinetics of oral testosterone undecanoate in males with hypogonadism.

Testosterone deficiency results from insufficient testosterone production. Testosterone therapy may require dose titration to reach eugonadal serum testosterone concentrations. The primary objective was the efficacy of oral testosterone undecanoate (TLANDO; Antares Pharma Inc.) in male patients with documented hypogonadism. Secondary objectives included a comparison of oral testosterone undecanoate safety and quality-of-life assessments to 1.62% topical testosterone gel (AndroGel 1.62%; AbbVie). In this phase 3 study, 315 patients were randomized 2:1 to oral testosterone undecanoate or 1.62% topical testosterone gel (NCT02081300). Patients received 225mg oral testosterone undecanoate twice daily, and doses were adjusted by 75mg/dose at weeks 4 and 8 based on average serum total testosterone concentration and maximum observed serum concentration. The primary endpoint was the proportion of patients receiving oral testosterone undecanoate with serum total testosterone concentration within the eugonadal reference range (300-1140ng/dL). Secondary endpoints included the proportion of patients with maximum serum total testosterone concentrations within predetermined limits, safety parameters, and quality-of-life endpoints including the Short Form-36v2 Health Survey, Psychosexual Daily Questionnaire, and International Prostate Symptom Score. Overall mean±SD baseline testosterone was 205.7±71.6ng/dL. For patients receiving oral testosterone undecanoate, 87.4% demonstrated a 24-h average serum total testosterone concentration within the reference range following titration. Oral testosterone undecanoate demonstrated a nominal statistically significantly greater mean change from baseline than 1.62% topical testosterone gel for Short Form-36v2 Health Survey measures of mental health (2.91vs. -0.10; p=0.035), and mental component summary (3.82vs. 0.55; p=0.009); and Psychosexual Daily Questionnaire measure of weekly negative mood (-0.57vs. -0.20; p=0.021). Safety endpoints were comparable between therapies. No deaths or treatment-related serious adverse events were reported. Male patients with hypogonadism receiving oral testosterone undecanoate 225mg twice daily demonstrated improvements in libido and sexual frequency. Serum testosterone concentrations were within the reference range in 87% of patients without dose titration.

Testosterone and the prevention of type 2 diabetes mellitus: therapeutic implications from recent trials.

Type 2 diabetes (T2D) is increasing to epidemic proportions and frequently associated with obesity and a low serum testosterone concentration in men. This review valuates recent randomized controlled trials (RCTs) investigating the effect of testosterone treatment on glycemic control and T2D prevention. The 2-year Testosterone for the Prevention of Type 2 diabetes Trial (T4DM) study showed that in men aged 50 years and over with visceral obesity and impaired glucose tolerance, testosterone treatment on the background of a lifestyle intervention reduced T2D risk by 40%. The Testosterone Effects on Atherosclerosis Progression in Aging Men and Testosterone Trials demonstrated modest improvements in insulin sensitivity and body composition. However, the Testosterone Replacement Therapy for Assessment of Long-Term Vascular Events and Efficacy Response in Hypogonadal Men trial found no significant glycemic benefits over 2 years. Recent data from the Diabetes Prevention Program Outcome Study support the cost efficacy and durability of metformin. In men at high risk of T2D, treatment with testosterone prevents the disease; however, there are caveats to its use and other approaches may be more applicable. Differences in trial designs, age groups, and outcome measures contribute to varying results. HbA1C is a suboptimal outcome measure. Future research should explore potential synergies between testosterone and GLP-1 receptor agonists in T2D management, while considering cost-effectiveness.