Selective lysine-specific demethylase 1 inhibitor, NCL1, could cause testicular toxicity via the regulation of apoptosis.

BACKGROUND: Recent studies have shown that epigenetic alterations, such as those involving lysine-specific demethylase 1 (LSD1), lead to oncogenic activation and highlight such alterations as therapeutic targets. However, studies evaluating the effect of LSD1 inhibitors on male fertility are lacking. OBJECTIVES: We analyzed the potential toxicity of a new selective LSD1 inhibitor, N-[(1S)-3-[3-(trans-2-aminocyclopropyl)phenoxy]-1-(benzylcarbamoyl)propyl] benzamide (NCL1), in testes. MATERIALS AND METHODS: Human testicular samples were immunohistochemically analyzed. Six-week-old male C57BL/6J mice were injected intraperitoneally with dimethyl sulfoxide vehicle (n = 15), or 1.0 (n = 15) or 3.0 (n = 15) mg/kg NCL1 biweekly. After five weeks, toxicity and gene expression were analyzed in testicular samples by ingenuity pathway analysis (IPA) using RNA sequence data and quantitative reverse transcriptase (qRT)-PCR; hormonal damage was analyzed in blood samples. NCL1 treated GC-1, TM3, and TM4 cell lines were analyzed by cell viability, chromatin immunoprecipitation, flow cytometry, and Western blot assays. RESULTS: LSD1 was mainly expressed in human Sertoli and germ cells, with LSD1 levels significantly decreased in a progressive meiosis-dependent manner; germ cells showed similar expression patterns in normal spermatogenesis and early/late maturation arrest. Histological examination revealed significantly increased levels of abnormal seminiferous tubules in 3.0 mg/kg NCL1-treated mice compared to control, with increased cellular detachment, sloughing, vacuolization, eosinophilic changes, and TUNEL-positive cells. IPA and qRT-PCR revealed NCL1 treatment down-regulated LSD1 activity. NCL1 also reduced total serum testosterone levels. Western blots of mouse testicular samples revealed NCL1 induced a marked elevation in cleaved caspases 3, 7, and 8, and connexin 43 proteins. NCL1 treatment significantly reduced GC-1, but not TM3 and TM4, cell viability in a dose-dependent manner. In flow cytometry analysis, NCL1 induced apoptosis in GC-1 cells. CONCLUSIONS: High-dose NCL1 treatment targeting LSD1 caused dysfunctional spermatogenesis and induced caspase-dependent apoptosis. This suggests the LSD1 inhibitor may cause testicular toxicity via the regulation of apoptosis.

PET imaging of 11C-labeled coenzyme Q10: Comparison of biodistribution between [11C]ubiquinol-10 and [11C]ubiquinone-10.

Coenzyme Q10 (CoQ10) plays a key role not only as an essential electron carrier in the mitochondrial electron transport chain, but also as an antioxidant to protect cells from oxidative stress. CoQ10 supplementation is expected to be effective for a variety of diseases. The predominant forms of CoQ10 are the ubiquinol-10 (reduced form) and ubiquinone-10 (oxidized form). Both forms of CoQ10 supplements are commercially available, however, their kinetic difference is still unclear. In order to conduct in vivo analysis of the kinetics of ubiquinol-10 and ubiquinone-10, we succeeded in synthesizing 11C-labeled ubiquinol-10 ([11C]UQL) and ubiquinone-10 ([11C]UQN), respectively. In the present study, we aimed to investigate the kinetics of [11C]UQL and [11C]UQN, both of which were administered via the tail vein of 8-week-old male Sprague-Dawley rats. Whole-body positron emission tomography (PET) imaging was performed to follow the time course of accumulation in the liver, spleen, brain, and other organs. Then, at the two typical time points at 20 or 90 min after injection, we conducted the biodistribution study. Various organs/tissues and blood were collected, weighed and counted with a gamma counter. Percent injected dose per gram of tissue (%ID/g) was calculated as the indicator of the accumulation of each compound. As the results, at both time points, %ID/g of [11C]UQL in the cerebrum, cerebellum, white adipose tissue, muscle, kidney, and testis were higher (P < 0.05) than that of [11C]UQN: at 90-min time point, %ID/g of [11C]UQL in the brown adipose tissue was higher (P < 0.05) than that of [11C]UQN: on the contrary, %ID/g of [11C]UQL in the spleen was lower (P < 0.05) than that of [11C]UQN at 90 min. In a separate study of the metabolite analysis in the plasma, UQL injected into the tail vein of rats was almost unchanged during the PET scanning time, but UQN was gradually converted to the reduced form UQL. Therefore, the uptake values of UQL into the tissues and organs were rather accurate but those of UQN might be the sum of UQN uptake and partly converted UQL uptake. These studies suggested that the accumulation level of administered CoQ10 differs depending on its redox state, and that CoQ10 redox state could be crucial for optimization of the effective supplementation.

Mental and physical fatigue-related biochemical alterations.

OBJECTIVE: To confirm fatigue-related biochemical alterations, we measured various parameters just before and after relaxation and fatigue-inducing mental or physical sessions. METHODS: Fifty-four healthy volunteers were randomized to perform relaxation and fatigue-inducing mental and physical sessions for 4 h in a double-blind, three-crossover design. Before and after each session, subjects were asked to rate their subjective sensations of fatigue, and blood, saliva, and urine samples were taken. RESULTS: After the fatigue-inducing mental and physical sessions, subjective scores of fatigue were increased. After the fatigue-inducing mental session, the vanillylmandelic acid level in urine was higher and plasma valine level was lower than after the relaxation session. In contrast, after the fatigue-inducing physical session, serum citric acid, triacylglycerol, free fatty acid, ketone bodies, total carnitine, acylcarnitine, uric acid, creatine kinase, aspartate aminotransferase, lactate dehydrogenase, cortisol, dehydroepiandrosterone, dehydroepiandrosterone sulfate, plasma branched-chain amino acids, transforming growth factor-beta1 and -beta2, white blood cell and neutrophil counts, saliva cortisol and amylase, and urine vanillylmandelic acid levels were higher and serum free carnitine and plasma total amino acids and alanine levels were lower than those after the relaxation session. CONCLUSION: Some mental or physical fatigue-related biochemical changes were determined. Various biochemical alterations reflecting homeostatic perturbation and its responses might be shown. We believe that our results contribute to clarifying the mechanism of fatigue, developing evaluation methods, and establishing a basis for treatment.