Effects of Nandrolone Stimulation on Testosterone Biosynthesis in Leydig Cells

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 3.9μM concentration of nandrolone and return to the basal level a 15.6μM dose of nandrolone. Nandrolone-induced testosterone increment was associated with upregulation of the steroidogenic acute regulatory protein (StAR) and downregulation of 17a-hydroxylase/17, 20 lyase (CYP17A1). Instead, a 15.6μM dose of nandrolone induced a down-regulation of CYP17A1. Further in vivo studies based on these data are needed to better understand the relationship between disturbed testosterone homeostasis and reproductive system impairment in male subjects

Nandrolone decanoate interferes with testosterone biosynthesis altering blood-testis barrier components

The aim of this study was to investigate whether nandrolone decanoate (ND) use affects testosterone production and testicular morphology in a model of trained and sedentary mice. A group of mice underwent endurance training while another set led a sedentary lifestyle and were freely mobile within cages. All experimental groups were treated with either ND or peanut oil at different doses for 6 weeks. Testosterone serum levels were measured via liquid chromatography-mass spectrometry. Western blot analysis and quantitative real-time PCR were utilized to determine gene and protein expression levels of the primary enzymes implicated in testosterone biosynthesis and gene expression levels of the blood-testis barrier (BTB) components. Immunohistochemistry and immunofluorescence were conducted for testicular morphological evaluation. The study demonstrated that moderate to high doses of ND induced a diminished serum testosterone level and altered the expression level of the key steroidogenic enzymes involved in testosterone biosynthesis. At the morphological level, ND induced degradation of the BTB by targeting the tight junction protein-1 (TJP1). ND stimulation deregulated metalloproteinase-9, metalloproteinase-2 (MMP-2) and the tissue inhibitor of MMP-2. Moreover, ND administration resulted in a mislocalization of mucin-1. In conclusion, ND abuse induces a decline in testosterone production that is unable to regulate the internalization and redistribution of TJP1 and may induce the deregulation of other BTB constituents via the inhibition of MMP-2. ND may well be considered as both a potential inducer of male infertility and a potential risk factor to a low endogenous bioavailable testosterone

Multimodality imaging: Bird’s eye view from The European Society of Cardiology Congress 2015 London, August 29-September 2, 2015

Cardiolog

Impedance spectroscopy characterization of lithium batteries with different ages in second life application

The aging behavior of lithium cell has a profound impact on its performance in terms of energy, power efficiency and capacity fade, especially when it is considered in End of Life (EOL) in automotive field. Lithium battery is considered in EOL if at 85-80% of nominal capacity. Today, the reusing of Electric and Hybrid Vehicles EOL batteries on less-demanding grid connected energy storage applications, giving them a second use/life, is an interesting solution to reduce high potential cost of lithium batteries. Currently, there is a lack of investigation of the performances of these second life batteries. In this paper, authors show the results of the impedance spectroscopy of 20 Ah lithium NMC batteries after EOL, exactly at 100, 85, 80, 60 and 50% of rated capacity, in a wide range of frequency: 450 mHz to 3.5 kHz. By results, there are many way to correlate battery state of health and battery impedance spectroscopy, especially when the battery is in second life

Electrical lithium battery performance model for second life applications

The aging behavior of lithium cell has a profound impact on its performance in terms of energy and power efficiency, especially when it is considered in End Of Life (EOL) in automotive field. Lithium battery is considered in EOL if at 85-80% of nominal capacity. Today, the reusing of Electric and Hybrid Vehicles EOL batteries on stationary applications, giving a second life to these batteries, is a solution to reduce high potential cost of lithium batteries. Currently, there is a lack of investigation of the performances of these second life batteries. This paper depicts the performance results of five NMC cells at different SOH, where four of these cells are considered in EOL, so ready to be investigated for possible second use. By results, there are many way to correlate battery SOH and battery performance, e.g. an increase of the internal resistance and the constant-voltage (CV) phase charging duration, the change of the open circuit voltage shape curve. Finally, a battery model based on electrical equivalent circuit is build and implemented in Matlab/Simulink, which is validated by comparison between voltage experimental and simulated data

Metabolic effects of hypoxia and sleep at hight altitude (5050)

Exposure to hypobaric hypoxia at high altitude (HA) is associated with worsening of hypoxemia during sleep. Since the endocrine system is involved in the adaptation to hypoxia, we assessed the effects of sleeping at HA (5050 m) on serum glucose, insulin, and cortisol levels and plasma leptin. Fasting venous blood samples were obtained in seven healthy subjects (M/F: 5/2, mean age±SD 41.9±13.7 yr) at sea level in the morning (SL), and at HA before (PRE) and after one night (POST) during which oxyhemoglobin saturation (SaO2) was recorded by pulse-oximetry. Mean nocturnal and mean lowest SaO2 decreased from 95±2% and 84±6% at SL, respectively, to 74± 5% and 64±7% at HA. Serum glucose was similar under all experimental conditions, while insulin at awakening decreased at HA (PRE: 16.2±8.2; POST: 6.3±1.8 mU/L, p<0.02; SL: 14.8±21.6 mU/L). Cortisol concentration was higher during both wakefulness and sleep at HA compared to SL (PRE: 125.8±53.8; POST: 315.4±68.7 ng/ml, p<0.0001; SL: 81.9±47.3 ng/ml). Plasma leptin did not show any significant difference. Insulin sensitivity, estimated by the homeostatic model (HOMA), increased from PRE to POST at HA (p<0.03). These results suggest that constant plasma glucose during sleep at HA is associated with increased insulin sensitivity. Increased cortisol level at HA suggests possible hypoxia-induced stress