Search results for "Leydig Cell"
showing 5 items of 5 documents
Effects of Nandrolone Stimulation on Testosterone Biosynthesis in Leydig Cells
2016
Anabolic androgenic steroids (AAS) are among the drugs most used by athletes for improving physical performance, as well as for aesthetic purposes. A number of papers have showed the side effects of AAS in different organs and tissues. For example, AAS are known to suppress gonadotropin‐releasing hormone, luteinizing hormone, and follicle‐stimulating hormone. This study investigates the effects of nandrolone on testosterone biosynthesis in Leydig cells using various methods, including mass spectrometry, western blotting, confocal microscopy and quantitative real‐time PCR. The results obtained show that testosterone levels increase at a 3.9 μM concentration of nandrolone and return to the ba…
Effect of Conjugated Linoleic Acid on Testosterone Levels In Vitro and In Vivo After an Acute Bout of Resistance Exercise
2012
The purposes of the present study were to investigate the effect of conjugated linoleic acid (CLA) supplementation on testosterone levels in vitro on a cell line derived from Leydig cells (R2C) and in vivo in the blood of physically active subjects before and after a resistance exercise bout. In vitro R2C cells were treated with different CLA concentrations (0-30 μM) for 24 and 48 hours. After treatment, supernatant media were tested to determine testosterone secretion. The CLA increased the testosterone secretion only after 48 hours. In vivo, 10 resistance-trained male subjects, in a double-blind placebo-controlled and crossover study design were randomized for 3 weeks of either 6 g·d⁻¹ CL…
Differential expression of estrogen receptors (ER?/ER?) in testis of mature and immature pigs
2004
High affinity estrogen receptors (ERs) mediate estrogen action in male reproductive tissues. The objective of the present study was the immunolocalization of estrogen receptor alpha and estrogen receptor beta in immature and mature testes of pig, a species in which the role of estrogens on gonadal function is scarcely known. Testes from 3 and 18 month-old pigs were investigated. Immunohistochemistry was performed on paraffin embedded-tissues using both mouse anti-human monoclonal IgG ERalpha and IgG ERbeta 1 isoform. Western blot analysis demonstrated antibody specificity. ERalpha staining was not observed in immature testes, but it was detected in spermatogonia, spermatocytes and in the mo…
Inhibin-α, CD99, HEA125, PLAP, and chromogranin immunoreactivity in testicular neoplasms and the androgen insensitivity syndrome
2000
We investigated 115 testicular and 3 epididymal tumors and 6 cases of the complete androgen insensitivity syndrome (AIS) for the expression of inhibin-alpha, CD99, HEA125, PLAP, and chromogranin, using monoclonal antibodies and standard immunhistochemical techniques. Ihibin-alpha was detected in the neoplastic cells in 27 of 27 primary Leydig cell tumors (LCTs), 1 of 1 metastatic LCT, 6 of 20 Sertoli cell tumors (SCTs), 4 of 5 juvenile granulosa cell tumors (GCTs), and 2 of 5 unclassified sex cord-stromal tumors (USCSTs). Except for 2 choriocarcinomas, the choriocarcinomatous component of 1 mixed germ cell tumor, and a small focus of inhibin-positive syncytiotrophoblast in 1 embryonal carci…
Clinical and metabolic findings in a 6-year-old boy with a Leydig cell tumour
2011
Aim: To analyse the urinary steroid metabolome in a boy who had true precocious puberty after a Leydig cell tumour. Method: Case report and detailed description of clinical and metabolic findings in a 7-year-old-boy with a Leydig cell tumour. Results: Before surgery, the urinary steroid metabolome showed an activation of an alternative route to gonadal androgens independent of dehydroepiandrosterone (DHEA). After surgery, the boy entered true precocious puberty. Under leuprolide acetate treatment, clinical and laboratory findings normalized. Conclusion: Central precocious puberty after precocious pseudopuberty may be more common than expected and should be considered in children with pe…