Superoxide is an Intrinsic Signaling Molecule Triggering Muscle Hypertrophy.

Aims: Redox signaling plays a key role in skeletal muscle remodeling induced by exercise and prolonged inactivity, but it is unclear which oxidant triggers myofiber hypertrophy due to the lack of strategies to precisely regulate individual oxidants in vivo. In this study, we used tetrathiomolybdate (TM) to dissociate the link between superoxide (O2•-) and hydrogen peroxide and thereby to specifically explore the role of O2•- in muscle hypertrophy in C2C12 cells and mice. Results: TM can linearly regulate intracellular O2•- levels by inhibition of superoxide dismutase 1 (SOD1). A 70% increase in O2•- levels in C2C12 myoblast cells and mice is necessary and sufficient for triggering hypertrophy of differentiated myotubes and can enhance exercise performance by more than 50% in mice. SOD1 knockout blocks TM-induced O2•- increments and thereby prevents hypertrophy, whereas SOD1 restoration rescues all these effects. Scavenging O2•- with antioxidants abolishes TM-induced hypertrophy and the enhancement of exercise performance, whereas the restoration of O2•- levels with a O2•- generator promotes muscle hypertrophy independent of SOD1 activity. Innovation and Conclusion: These findings suggest that O2•- is an endogenous initiator of myofiber hypertrophy and that TM may be used to treat muscle wasting diseases. Our work not only suggests a novel druggable mechanism to increase muscle mass but also provides a tool for precisely regulating O2•- levels in vivo.

Intermittent fasting shifts the diurnal transcriptome atlas of transcription factors.

Intermittent fasting remains a safe and effective strategy to ameliorate various age-related diseases, but its specific mechanisms are not fully understood. Considering that transcription factors (TFs) determine the response to environmental signals, here, we profiled the diurnal expression of 600 samples across four metabolic tissues sampled every 4 over 24 h from mice placed on five different feeding regimens to provide an atlas of TFs in biological space, time, and feeding regimen. Results showed that 1218 TFs exhibited tissue-specific and temporal expression profiles in ad libitum mice, of which 974 displayed significant oscillations at least in one tissue. Intermittent fasting triggered more than 90% (1161 in 1234) of TFs to oscillate somewhere in the body and repartitioned their tissue-specific expression. A single round of fasting generally promoted TF expression, especially in skeletal muscle and adipose tissues, while intermittent fasting mainly suppressed TF expression. Intermittent fasting down-regulated aging pathway and upregulated the pathway responsible for the inhibition of mammalian target of rapamycin (mTOR). Intermittent fasting shifts the diurnal transcriptome atlas of TFs, and mTOR inhibition may orchestrate intermittent fasting-induced health improvements. This atlas offers a reference and resource to understand how TFs and intermittent fasting may contribute to diurnal rhythm oscillation and bring about specific health benefits.

Plasmonic scattering imaging of single Cu2-xSe nanoparticle for Hg2+ detection.

The development of new efficient contrast nanoprobe has been greatly concerned in the field of scattering imaging for sensitive and accurate detection of trace analytes. In this work, the non-stoichiometric Cu2-xSe nanoparticle with typical localized surface plasmon resonance (LSPR) properties originating from their copper deficiency as a plasmonic scattering imaging probe was developed for sensitive and selective detection of Hg2+ under dark-field microscopy. Hg2+ can compete with Cu(I)/Cu(II) which were sources of optically active holes coexisting in these Cu2-xSe nanoparticles for its higher affinity with Se2-. The plasmonic properties of Cu2-xSe were adjusted effectively. Thus, the color scattering images of Cu2-xSe nanoparticles was changed from blue to cyan, and the scattering intensity was obviously enhanced with the dark-field microscopy. There was a linear relationship between the scattering intensity enhancement and the Hg2+ concentration in the range of 10-300 nM with a low detection limit of 1.07 nM. The proposed method has good potential for Hg2+ detection in the actual water samples. This work provides a new perspective on applying new plasmonic imaging probe for the reliable determination of trace heavy metal substances in the environment at a single particle level.

A new species of Pseudopoda (Araneae, Sparassidae) from China, with the description of different and distinctive internal ducts of the female vulva.

One new species of the genus Pseudopoda Jäger, 2000, Pseudopodadeformis Gong & Zhong, sp. nov. (♂, ♀), is described and documented with digital images from Shennongjia Forestry District, Hubei Province, China, based on morphology and DNA barcodes. This new species is separated from other Pseudopoda species by the unique type of internal ducts of the female vulva that are curved longitudinally, forming a narrow triangle or trapezoidal shape. In addition, DNA barcodes for this species are provided.

Hepatic fibrosis: Targeting peroxisome proliferator-activated receptor alpha from mechanism to medicines.

Liver fibrosis is the result of sustained chronic liver injury and inflammation leading to hepatocyte cell death followed by the formation of fibrous scars, which is the hallmark of NASH and alcoholic steatohepatitis and can lead to cirrhosis, HCC, and liver failure. Although progress has been made in understanding the pathogenesis and clinical consequences of hepatic fibrosis, therapeutic strategies for this disease are limited. Preclinical studies suggest that peroxisome proliferator-activated receptor alpha plays an important role in preventing the development of liver fibrosis by activating genes involved in detoxifying lipotoxicity and toxins, transrepressing genes involved in inflammation, and inhibiting activation of hepatic stellate cells. Given the robust preclinical data, several peroxisome proliferator-activated receptor alpha agonists have been tested in clinical trials for liver fibrosis. Here, we provide an update on recent progress in understanding the mechanisms by which peroxisome proliferator-activated receptor alpha prevents fibrosis and discuss the potential of targeting PPARα for the development of antifibrotic treatments.

Sympathetic blockage attenuates fasting-induced hepatic steatosis.

Although the central nervous system coordinates whole-body metabolism, the neural mechanism for hepatic steatosis remains unclear. This study is aimed to explore the neural mechanism of fasting-induced hepatic steatosis. Mice were pretreated with 6-hydroxydopamine to block sympathetic nerve activity before fasting, and to explore the potential effects of chemical sympathectomy on fasting-induced hepatic steatosis and transcriptional changes. Twenty-four hours fasting led to obvious hepatic steatosis, low-core temperature, and similar effects to cold-induced white adipose lipolysis. The alterations in hepatic mRNA expression revealed that the hepatic lipid accumulation did not result from an increase in hepatic lipogenesis or a decrease in fatty acid oxidation but from enhanced fatty acid uptake as indicated by upregulation of CD36. Blockage of the sympathetic nervous system via chemical sympathectomy attenuated fasting-induced hepatic steatosis and suppressed CD36 upregulation in the liver, but did not obviously alter the expression of genes associated with lipogenesis or fatty acid oxidation. These findings indicate that the sympathetic nervous system orchestrates the mechanism for fasting-induced hepatic steatosis via modulating CD36 expression and adipose fat trafficking into the liver, which provides clues to reveal new targets for fatty liver diseases.

Circadian transcriptional pathway atlas highlights a proteasome switch in intermittent fasting.

While intermittent fasting is a safe strategy to benefit health, it remains unclear whether a "timer" exists in vivo to record fasting duration and trigger a transcriptional switch. Here, we map a circadian transcriptional pathway atlas from 600 samples across four metabolic tissues of mice under five feeding regimens. Results show that 95.6% of detected canonical pathways are rhythmic in a tissue-specific and feeding-regimen-specific manner, while only less than 25% of them induce changes in transcriptional function. Fasting for 16 h initiates a circadian resonance of 43 pathways in the liver, and the resonance punctually switches following refeeding. The hepatic proteasome coordinates the resonance, and most genes encoding proteasome subunits display a 16-h fasting-dependent transcriptional switch. These findings indicate that the hepatic proteasome may serve as a fasting timer and a coordinator of pathway transcriptional resonance, which provide a target for revealing the underlying mechanism of intermittent fasting.

First description of the female of Sinopodayichangensis Zhu, Zhong & Yang, 2020 (Araneae, Sparassidae).

Sinopodayichangensis Zhu, Zhong & Yang, 2020 was described from a single male from Qiaoliao Village, Hubei Province, China. To date, no additional specimens have been recorded. The female is reported for the first time from the type locality. Detailed morphological descriptions of the female, with photographs of living specimens and copulatory organs, are provided.

Ultrasonic diagnosis of asymptomatic rupture of uterine in second trimester of pregnancy after laparoscopic surgery for interstitial pregnancy: a case report.

BACKGROUND: Uterine rupture is a rare, life-threatening event in obstetrics that may be fatal for the mother and fetus. Therefore, obstetricians need to pay attention to and should consider the antenatal diagnosis of uterine rupture in women having its risk factors. Successful conservative management for asymptomatic uterine rupture due to previous laparoscopic surgery for interstitial pregnancy has already been reported but remains understudied. CASE PRESENTATION: A 39-year-old woman was diagnosed asymptomatic uterine rupture at 22 weeks gestation by a routine second-trimester ultrasound scan. She had a history of laparoscopic salpingectomy with cornual wedge resection for interstitial pregnancy 10 months before this pregnancy. Refusing doctor's twice advice of terminating the pregnancy, the patient insisted carrying on the pregnancy, and followed up by ultrasound and magnetic resonance imaging. Fetal growth was appropriate, fetal movements were good and the patient had no symptoms, without uterine contraction or amniotic fluid loss throughout follow-up period. Caesarean section was carried out at 34 + 1 weeks with a good maternal and neonatal outcome. CONCLUSIONS: A previous history of laparoscopic salpingectomy with cornual wedge resection could be a risk factor for uterine rupture in pregnant women. Sonographers should be alert to this potential risk in pregnant women with a history of laparoscopic salpingectomy with cornual wedge resection even in asymptomatic patients.

Serum interleukin-6, interleukin-17A, and tumor necrosis factor-alpha in patients with recurrent aphthous stomatitis.

BACKGROUND: Recurrent aphthous stomatitis remains the most common disease of the oral mucosa. The aim of this study was to investigate the clinical significance of serum interleukin-6, interleukin-17A, and tumor necrosis factor-alpha in recurrent aphthous stomatitis. METHODS: Using flow cytometry analysis, we detect the level of serum interleukin-2, interleukin-6, interleukin-17A, tumor necrosis factor-alpha, and interferon-gamma in 127 patients with recurrent aphthous stomatitis and 20 healthy control cases; compare; and analyze the correlation of each index. RESULTS: The levels of serum interleukin-2, interleukin-6, tumor necrosis factor-alpha, and interferon-gamma in the recurrent aphthous stomatitis group were higher than in the control group, and the differences were statistically significant (P < .05). There was no significant difference in interleukin-17A between the two groups. CONCLUSION: The levels of serum interleukin-6 and tumor necrosis factor-alpha in recurrent aphthous stomatitis patients were significantly increased. Considering that serum TNF-α was mostly within the normal range, its role in the pathology of RAS needed to be further explored.