Investigation of the pathogenesis of ADAR1 gene in dyschromatosis symmetrica hereditaria.

The pathogenesis of dyschromatosis symmetrica hereditaria (DSH) has not been well defined. In this study, we sought to investigate the influence of the ADAR1 gene on DSH both in vitro and in vivo. Morpholino knockdown of adar1 in zebrafish produced phenotypes characterized by polarity changes, and abnormal migration and distribution of melanocytes. Differential expression of C-KIT and distinct patterns of apoptosis between hyperpigmented and hypopigmented areas in DSH patient were detected by means of immunohistochemical methods and TUNEL assays, respectively. This study revealed that adar1 knockdown in a zebrafish model resulted in abnormal migration and changes in the cell polarity of melanocytes, and provided novel insight into the mechanism of DSH pathogenesis.

Passive exercise is an effective alternative to HRT for restoring OVX induced mitochondrial dysfunction in skeletal muscle.

Background: Postmenopausal women are more prone to develop muscle weakness, which is strongly associated with impairment of mitochondrial function in skeletal muscle. This study aimed to examine the impact of a passive exercise modality, whole-body vibration training (WBVT), on muscle mitochondrial function in ovariectomized (OVX) mice, in comparison with 17ß-estradiol (E2) replacement. Methods: Female C57BL/6J mice were assigned to four groups: sham operation control group (Sham), ovariectomized group (OVX), OVX with E2 supplement group (OVX+E), and OVX with WBVT group (OVX+W). The estrous cycle, body weight, body composition, and muscle strength of the mice were monitored after the operation. Serum E2 level was assessed by enzyme-linked immunosorbent assay (ELISA). The ATP levels were determined using a luciferase-catalyzed bioluminescence assay. The activity of mitochondrial respiration chain complexes was evaluated using high-resolution respirometry (O2K). Expression levels of oxidative phosphorylation (OXPHOS), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), and mitochondrial transcription factor A (TFAM) were detected using western blotting. Results: We observed decreased muscle strength and impaired mitochondrial function in the skeletal muscle of OVX mice. The vibration training alleviated these impairments as much as the E2 supplement. In addition, the vibration training was superior to the ovariectomy and the estradiol replacement regarding the protein expression of PGC-1α and TFAM. Conclusion: WBVT improves the OVX-induced decline in muscle strength and impairment of mitochondrial function in the skeletal muscle. This passive exercise strategy may be useful as an alternative to E2 replacement for preventing menopausal muscular weakness. Further studies are needed to understand the effects of WBVT on various physiological systems, and precautions should be taken when implementing it in patient treatment.

17beta-estradiol alleviates contusion-induced skeletal muscle injury by decreasing oxidative stress via SIRT1/PGC-1α/Nrf2 pathway.

PURPOSE: This study aimed to investigate the role of 17ß-estradiol (E2) in the repair of contusion-induced myoinjury in mice and to identify the underlying molecular mechanisms. METHODS: In vivo, contusion protocol was performed for preparing mice myoinjury model, and Injection (i.p.) of 17ß-estradiol (E2) or estrogen receptor antagonist ICI 182,780, or ovariectomy (OVX), was used to alter estrogen level of animal models. In vitro, C2C12 myoblasts were treated with H2O2 (oxidative stress inducer), SIRT1 inhibitor EX527, or aromatase inhibitor anastrozole. Serum E2 level was assessed by enzyme-linked immunosorbent assay (ELISA). Muscle damage repair was evaluated by H&E staining and the activities of serum creatine kinase (CK) and lactate dehydrogenase (LDH). The oxidative stress was estimated by the levels of catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA). Western blot was performed to measure the protein expressions of SIRT1, PGC-1α, Nrf2, and HO-1. RESULTS: We observed the elevated serum E2 levels and the upregulated oxidative stress in damaged muscle in female mice after contusion-induction. The E2 administration in vivo alleviated contusion-induced myoinjury in OVX mice by reducing CK and LDH activities, suppressing oxidative stress, and enhancing the expression levels of SIRT1, PGC-1α, Nrf2, and HO-1. These effects were inhibited by treatment with an ERα/ß antagonist. Moreover, EX527 or anastrozole treatment exacerbated H2O2-induced growth inhibition and oxidative stress, and expression downregulation of SIRT1, PGC-1α, Nrf2, and HO-1 in C2C12 cells in vitro. CONCLUSION: Our results suggest that E2 is a positive intervention factor for muscle repair followed contusion-induced myoinjury, through its effects on suppressing oxidative stress via activating the SIRT1/PGC-1α/Nrf2 pathway.

Correction to: Runners' metabolomic changes following marathon.

[This corrects the article DOI: 10.1186/s12986-020-00436-0.].

Runners' metabolomic changes following marathon.

INTRODUCTION: Marathon, as a long-distance aerobic exercise, has become a fashionable or popular sport. However, little is known about the holistic metabolic changes occurring within the serum metabolome of athletes after the completion of a marathon. OBJECTIVES: The goal of current study was to have an in-depth understanding of the impact of marathon on human metabolomics as well as the relationships among a variety of metabolites. METHODS: The 20 studied subjects were all adult males who participated in a marathon. The serum samples of these participants were collected before and after the marathon and the biochemical metabolites in the serum were identified by an untargeted two-dimensional gas chromatography time-of-flight mass spectrometry. RESULTS: All participants completed the marathon within 3 h. Compared to those before exercise, serum urea and creatine kinase, as well as cortisol, elevated significantly (p < 0.05), whereas testosterone decreased significantly (p < 0.01). Metabolomic analysis showed that, compared to those before the competition, metabolites pyruvic acid, glyceric acid, malic acid, cis-aconitic acid, galacturonic acid, methyl fumaric acid, maltotriose, and others increased significantly after the competition (p < 0.05), but glucosamine and O-succinyl-L-homoserine decreased significantly (p < 0.05). Amino acid indexes, such as alanine, L-tyrosine and phenylalanine, increased significantly after exercise compared with those before exercise (p < 0.05), whereas serine, valine and asparagine decreased significantly (p < 0.05). Lipid metabolism indexes, glycerol, glyceric acid, octanoic acid, and quinic acid increased significantly (p < 0.05). Theophylline, xanthine and other indicators of caffeine metabolism increased significantly (p < 0.05). Furthermore, marathon performance, fat percentage, VO2max, and hemoglobin were correlated with the serum metabonomic indicators, so were serum testosterone and cortisol. CONCLUSION: These results illustrate that the metabolism of glucose and lipid of the athletes was enhanced following the marathon match. In addition, the metabolism of glucosamine was decreased and the metabolism of caffeine was increased. Our data provide new insights for marathon performance and nutritional status.