Trenbolone Research Articles (Page 1)

A competitive cathodic photoelectrochemical sensor based on a signal amplification of CdIn2S4 photoanode for trenbolone detection

Photocurrent-polarity-switching photoelectrochemical and electrochemical dual-mode sensing platform for the highly selective detection of trenbolone

Ultrasensitive ECL immunosensor for trenbolone detection based on double-assisted signal amplification strategy of Nb2O5-decorated TiO2 nanorods and Co3O4-Co3(PO4)2 nanosheets

A controlled-release strategy can meet the needs of sensitive environmental monitoring for pollutants through a self-on/off mode. In this work, an electrochemiluminescence (ECL) biosensor with controlled-release triggering electrostatic attraction elimination and biomolecular stimulated response strategies was constructed to detect environmental steroid hormones sensitively. The blocked pores on the aminated mesoporous silica nanocontainers were opened by specific binding between the trenbolone (TB) antigen and the antibody. The released l-cysteine counteracted the negative charge on the MnO2 NF surface through the redox reaction between -SH and MnO2, making the electrostatic interaction between the MnO2 NFs and the Ru(dcbpy)32+ disappear. Ru(dcbpy)32+ released an ECL signal on the electrode, thus completing the controlled-release triggering electrostatic attraction elimination strategy. In addition, with the TB antibody as the target and the competition strategy between the TB antigen and the standard substance, the constructed controlled-release ECL biosensor was used to detect the TB standard substance. Moreover, MnO2 NFs as the substrate of the ECL biosensor increased the active specific surface area of the electrode, effectively catalyzing the production of OH• and O2•-, thus endowing the ECL biosensor with coreactant-catalytic enhancement characteristic and further improving its ECL performance. This sensitive signal response brought about a low limit of detection of 2.53 fg/mL for the constructed ECL biosensor, which contributed a feasible idea for efficient trace analysis of pollutants in the environment.

Porphyrin-based metal-organic frameworks enhanced electrochemiluminescence (ECL) by overcoming aggregation-caused quenching: A new ECL emitter for the detection of trenbolone

A competitive photoelectrochemical sensor based on the in situ formation of BiOBr/Bi2S3 by Cs3Bi2Br9 for the detection of trenbolone

Acute environmental stressors such as short-term exposure to pollutants can have lasting effects on organisms, potentially impacting future generations. Parental exposure to toxicants can result in changes to the epigenome (e.g., DNA methylation) that are passed down to subsequent, unexposed generations. However, it is difficult to gauge the cumulative population-scale impacts of epigenetic effects from laboratory experiments alone. Here, we developed a size- and age-structured delay-coordinate population model to evaluate the long-term consequences of epigenetic modifications on population sustainability. The model emulated changes in growth, mortality, and fecundity in the F0, F1, and F2 generations observed in experiments in which larval Menidia beryllina were exposed to environmentally relevant concentrations of bifenthrin (Bif), ethinylestradiol (EE2), levonorgestrel (LV), or trenbolone (TB) in the parent generation (F0) and reared in clean water up to the F2 generation. Our analysis suggests potentially dramatic population-level effects of repeated, chronic exposures of early-life stage fish that are not captured by models not accounting for those effects. Simulated exposures led to substantial declines in population abundance (LV and Bif) or near-extinction (EE2 and TB) with the exact trajectory and timeline of population decline dependent on the combination of F0, F1, and F2 effects produced by each compound. Even acute one-time exposures of each compound led to declines and recovery over multiple years due to lagged epigenetic effects. These results demonstrate the potential for environmentally relevant concentrations of commonly used compounds to impact the population dynamics and sustainability of an ecologically relevant species and model organism.

In this study, a portable electrochemiluminescence sensor chip was designed for trenbolone (TBE) trace detection in environmental water. First, a stable ECL signal was obtained with low-toxicity 3,4,9,10-perylenetetracarboxylic acid (PTCA) as a luminophore and persulfate (S2O82-) as a coreactant. Second, hollow-structured Cu2MoS4 was introduced as a coreaction accelerator to catalyze S2O82- reduction. The reversible conversion of the mixed-valence transition metal ions in Cu2MoS4 (Cu+/Cu2+ and Mo4+/Mo6+) greatly promoted the generation of the sulfate radical (SO4•-). Meanwhile, the special porous structure of Cu2MoS4 possessed a large specific surface area, thus enhancing its catalytic performance. Based on these enhancement mechanisms, a strong ECL signal was acquired, which improved the detection sensitivity of the constructed sensor. Importantly, a microfluidic chip was introduced for sensing detection, thereby improving the practicality of the sensor. The developed sensor chip was miniature and portable, exhibiting high sensitivity for TBE detection with a wide linear range (10 fg/mL-100 ng/mL) and lower detection limit (3.32 fg/mL). This was of great significance for timely and rapid analysis of steroid pollutants in natural water.

Stereoisomers of estradiol (E2) or trenbolone (TB) can occur together in the environment receiving human or livestock wastes. However, the effect of their co-occurrence on persistence has not been well elucidated. A sandy and a silt loam sediment were used to establish microcosms with α- and β-isomers of E2 or TB spiked individually and together. Sediments were sampled periodically and analyzed for E2 and TB isomers and their transformation products using derivatization gas chromatography-mass spectrometry. Results showed that stereoselective degradation was significant for E2 in both sediments and TB in the sandy sediment with β-isomers decaying more rapidly than α-isomers. In the sandy sediment containing limited natural organic carbon and nutrients, co-occurrence of both isomers of either E2 or TB decreased the dissipation rates. In the silt loam sediment with abundant organic matter and nutrients, the decay rates of both isomers were not changed in the presence of the other isomer. Estrone (E1) and trendione (TD) were detected as primary metabolites of E2 and TB isomers, respectively. The formation and decay profiles of E1 were similar in both sediments with 92-100% of E2 transformed to E1. The TD profiles were different across sediments with ∼100% of TB transformed to TD except in the sandy sediment where 51-60% of 17α-TB was converted to TD. These results indicate that the transformation processes of steroid hormone are stereoselective in sediment and co-occurrence of stereoisomers can prolong steroid persistence and thus pose greater environmental risk.

The increasing prevalence of obesity adds another dimension to the pathophysiology of testosterone (TEST) deficiency (TD) and potentially impairs the therapeutic efficacy of classical TEST replacement therapy. We investigated the therapeutic effects of selective androgen receptor modulation with trenbolone (TREN) in a model of TD with the metabolic syndrome (MetS). Male Wistar rats (n=50) were fed either a control standard rat chow (CTRL) or a high-fat/high-sucrose (HF/HS) diet. After 8 weeks of feeding, rats underwent sham surgery or an orchiectomy (ORX). Alzet miniosmotic pumps containing either vehicle, 2-mg/kg·d TEST or 2-mg/kg·d TREN were implanted in HF/HS+ORX rats. Body composition, fat distribution, lipid profile, and insulin sensitivity were assessed. Infarct size was quantified to assess myocardial damage after in vivo ischaemia reperfusion, before cardiac and prostate histology was performed. The HF/HS+ORX animals had increased sc and visceral adiposity; circulating triglycerides, cholesterol, and insulin; and myocardial damage, with low circulating TEST compared with CTRLs. Both TEST and TREN protected HF/HS+ORX animals against sc fat accumulation, hypercholesterolaemia, and myocardial damage. However, only TREN protected against visceral fat accumulation, hypertriglyceridaemia, and hyperinsulinaemia and reduced myocardial damage relative to CTRLs. TEST caused widespread cardiac fibrosis and prostate hyperplasia, which were less pronounced with TREN. We propose that TEST replacement therapy may have contraindications for males with TD and obesity-related MetS. TREN treatment may be more effective in restoring androgen status and reducing cardiovascular risk in males with TD and MetS.

Improvements in body composition, cardiometabolic risk factors and insulin sensitivity with trenbolone in normogonadic rats

Abstract The aim of the study was to test and compare the cytotoxic potential of two synthetic oestrogens: diethylstilboestrol (DES) and ethinyloestradiol (EE2) and two androgens: testosterone propionate (TP) and trenbolone (TREN) on two cell lines. The fibroblast cell line Balb/c 3T3 and the hepatoma cell line HepG2 were selected. To get more insight into the mode of toxic action, four methods were used, which evaluated different biochemical endpoints: mitochondrial activity (3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide reduction assay), lysosomal activity (neutral red uptake assay), total protein content, and lactate dehydrogenase release. Cytotoxicity was assessed after 24, 48, and 72 h exposure to eight concentrations ranging from 0.78 to 100 μg/mL. Concentration- and time- dependent effects were observed. Depending on the line and assay used, half maximal effective concentration after 72 h (EC50-72h) values ranged as follows: DES 1-13.7 μg/mL (Balb/c 3T3) and 3.7-5.2 μg/mL (HepG2); EE2 2.1-14.3 μg/mL (Balb/c 3T3) and 1.8-7.8 μg/mL (HepG2); TP-14.9-17.5 μg/mL (Balb/c 3T3), and 63.9- 100 μg/mL (HepG2); and TREN 11.3-31.4 μg/mL (Balb/c 3T3) and 12.5-59.4 μg/mL (HepG2). The results revealed that oestrogens were more toxic than androgens and the most affected endpoint was mitochondrial activity. In contrast to oestrogens, for which EC50-72h values were similar in both lines and by all assays used, Balb/c 3T3 cells were more sensitive than HepG2 cells to TP.

Evidence of small modulation of ethinylestradiol induced effects by concurrent exposure to trenbolone in male eelpout Zoarces viviparus

Trenbolone (TREN), a potent testosterone analog, does not undergo 5[alpha]‐reduction to the more potent metabolite dihydrotestosterone (DHT) and may produce androgenic effects without DHT‐mediated adverse effects. The purpose of this study was to investigate the mechanism underlying the trenbolone – induced augmentation of LABC muscle mass in orchiectomized (ORX) rats. Forty, 10 month old male F344/Brown Norway rats were randomized into SHAM, ORX, ORX+TE, and ORX+TREN groups. Following surgery, animals recovered for 1 week and then were treated with vehicle, TE, or TREN by weekly i.m. injection. 5 weeks of TE administration nearly doubled prostate mass, while TREN resulted in a nonsigificant reduction in prostate mass, compared with SHAMs. ORX induced a significant 2‐fold elevation atrogin‐1 and a 3‐fold elevation in Muscle RING Finger‐1 mRNA expression, effects which were completely abolished by TE and TREN. Interestingly, TREN induced a greater decrease in atrogin‐1 gene expression compared to TE. These data suggest that TREN may prevent muscle loss after ORX through inhibiting master genes that regulate skeletal muscle atrophy. This work was supported by VA Merit Award to SEB and a VA Career Development Award‐2 to JFY.

Estrogens and synthetic androgens in manure slurry from trenbolone acetate/estradiol implanted cattle and in waste-receiving lagoons used for irrigation

Preparation of an immunoaffinity column and its application in sample cleanup for methandrostenolone residues detection

Land application of animal manure has been identified as a source of natural and synthetic hormone contaminants that are frequently detected down-gradient of agricultural operations. Much research on the environmental fate of hormones has focused on the structural isomers most biologically active in mammals, e.g., the 17β-isomers of the estrogen estradiol (E2) and the synthetic androgen trenbolone (TB). However, recent work has shown that the α- and β-isomers of E2 and TB can cause comparable effects on certain aquatic species. To improve our understanding and ability to predict isomer-specific interactions with environmental sorbents, we measured the association (K(DOC)) of the α- and β-isomers of E2 and TB as well as their primary metabolites (estrone and trendione) with two commercial dissolved organic carbon (DOC) sources by measuring both free and DOC-bound hormone concentrations. We also measured solvent-water partition coefficients partitioning (K(SW)) for the same hormones using hexane, toluene, and octanol. Log K(DOC)(*), log K(OC) (OC-normalized sorption by soils), and K(OW) values are all greater for the β-isomer except between the E2 isomers. Theoretical descriptors reflecting electronic character and solute-solvent interactions were calculated to elucidate isomer-specific behavior. Trends for log K(OW) and log K(DOC) among hormones as well as between isomers are explained reasonably well by computed electrostatic potential and H-bonding parameters.

Application of protein expression profiling to screen chemicals for androgenic activity

Generation of anti-trenbolone monoclonal antibody and establishment of an indirect competitive enzyme-linked immunosorbent assay for detection of trenbolone in animal tissues, feed and urine

Testosterone enanthate (TE) increases serum testosterone (T), prostate mass, and hemoglobin (Hb) in orchidectomized (ORX) rodents. Trenbolone enanthate (TREN) is a synthetic analogue of T which does not undergo 5‐alpha reduction or aromatization; suggesting that it may increase Hb without inducing prostate enlargement. Our purpose was to determine whether TREN administration results in elevated circulating trenbolone (TR) and elevated Hb without prostate enlargement. Thirty‐five 10 month old male Brown Norway rats were randomized into Sham+vehicle (V), ORX+V, ORX+T, and ORX+TREN groups and received weekly drug injections for 42 days. Injections of TE, resulted in elevated serum concentrations of T compared to other treatments (p<0.05). Whereas, injections of TREN increased serum TR levels without increasing serum T (p<0.05). Prostate mass was 78% lower in ORX and 30% lower in TR groups vs. SHAM (p<0.05); while prostate mass in ORX+T was nearly double SHAM (p<0.05). Both T and TREN elevated Hb by 11% compared to ORX (p<0.05). Ultimately, ORX+TREN elevated Hb concentrations and reduced prostate mass; suggesting that TR may selectively activate androgen receptors. Supported by a VA Merit Award (SEB).