In vivo study of gene expression with an enhanced dual-color fluorescent transcriptional timer.

Fluorescent transcriptional reporters are widely used as signaling reporters and biomarkers to monitor pathway activities and determine cell type identities. However, a large amount of dynamic information is lost due to the long half-life of the fluorescent proteins. To better detect dynamics, fluorescent transcriptional reporters can be destabilized to shorten their half-lives. However, applications of this approach in vivo are limited due to significant reduction of signal intensities. To overcome this limitation, we enhanced translation of a destabilized fluorescent protein and demonstrate the advantages of this approach by characterizing spatio-temporal changes of transcriptional activities in Drosophila. In addition, by combining a fast-folding destabilized fluorescent protein and a slow-folding long-lived fluorescent protein, we generated a dual-color transcriptional timer that provides spatio-temporal information about signaling pathway activities. Finally, we demonstrate the use of this transcriptional timer to identify new genes with dynamic expression patterns

Hyperbaric oxygen preconditioning for prevention of acute high-altitude diseases: Fact or fiction?

Acute high-altitude diseases, including acute mountain sickness (AMS), high-altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE), have been recognized as potentially lethal diseases for altitude climbers. Various preconditioning stimuli, including hyperbaric oxygen (HBO), have been proposed to prevent acute high-altitude diseases. Herein, we reviewed whether and how HBO preconditioning could affect high-altitude diseases and summarized the results of current trials. Evidence suggests that HBO preconditioning may be a safe and effective preventive method for acute high-altitude diseases. The proposed mechanisms of HBO preconditioning in preventing high-altitude diseases may involve: 1) protection of the blood-brain barrier and prevention of brain edema, 2) inhibition of the inflammatory responses, 3) induction of the hypoxia-inducible factor and its target genes, and 4) increase in antioxidant activity. However, the optimal protocol of HBO preconditioning needs further exploration. Translating the beneficial effects of HBO preconditioning into current practice requires the “conditioning strategies” approach. More large-scale and high-quality randomized controlled studies are needed in the future

MicroRNA miR-326 regulates TH-17 differentiation and is associated with the pathogenesis of multiple sclerosis

MicroRNA miR-326 regulates TH-17 differentiation and is associated with the pathogenesis of multiple sclerosis Changsheng Du1,5, Chang Liu1,5, Jiuhong Kang1,2, Guixian Zhao3, Zhiqiang Ye4, Shichao Huang1, Zhenxin Li3, Zhiying Wu3 & Gang Pei1,2 Interleukin 17 (IL-17)-producing T helper cells (TH-17 cells) are increasingly recognized as key participants in various autoimmune diseases, including multiple sclerosis. Although sets of transcription factors and cytokines are known to regulate TH-17 differentiation, the role of noncoding RNA is poorly understood. Here we identify a TH-17 cell–associated microRNA, miR-326, whose expression was highly correlated with disease severity in patients with multiple sclerosis and mice with experimental autoimmune encephalomyelitis (EAE). In vivo silencing of miR-326 resulted in fewer TH-17 cells and mild EAE, and its overexpression led to more TH-17 cells and severe EAE. We also found that miR-326 promoted TH-17 differentiation by targeting Ets-1, a negative regulator of TH-17 differentiation. Our data show a critical role for microRNA in TH-17 differentiation and the pathogenesis of multiple sclerosis

Effect of transcranial direct current stimulation for patients with disorders of consciousness: A systematic review and meta-analysis

IntroductionTranscranial direct current stimulation (tDCS) could potentially facilitate consciousness improvement in patients with disorders of consciousness (DOC). The aim of this study was to investigate the therapeutic efficacy of tDCS on consciousness recovery for patients with DOC.MethodsEight databases were systematically searched from their inception to June 2022. Quality of included studies were assessed using PEDro score and Cochrane’s risk of bias assessment. All statistical analyses were performed using RevMan software. Seventeen studies with 618 patients were identified eligible for this study, and fifteen studies with sufficient data were pooled in the meta-analysis.ResultsThe results of meta-analysis showed a significant effect on increasing GCS scores (MD = 1.73; 95% CI, 1.28–2.18; P < 0.01) and CRS-R scores (MD = 1.28; 95% CI = 0.56–2.00; P < 0.01) in favor of the real stimulation group as compared to sham. The results of subgroup analysis demonstrated that only more than 20 sessions of stimulation could significantly enhance the improvement of GCS scores and the CRS-R scores. Moreover, the effect of tDCS on CRS-R score improvement was predominant in patients with minimal conscious state (MCS) (MD = 1.84; 95% CI = 0.74–2.93; P < 0.01).ConclusionAnodal tDCS with sufficient stimulation doses appears to be an effective approach for patients with MCS, in terms of CRS-R scores.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022336958

Hemoglobin level is negatively associated with sarcopenia and its components in Chinese aged 60 and above

Introduction: Sarcopenia and low hemoglobin level are common in older adults. Few studies have evaluated the association between hemoglobin level and sarcopenia and with inconsistent findings. The multifaceted effects of sarcopenia on the human body and the high prevalence of anemia in the Chinese population make it necessary to explore the association between the two. Methods: Using the China Health and Retirement Longitudinal Study (CHARLS), we explored the association between hemoglobin with sarcopenia and its components in the Chinese population aged 60 and above. Multivariate logistic and Cox proportional hazards models were constructed to examine the association of hemoglobin level with sarcopenia and sarcopenia components in individuals aged 60 years or above. The subgroup analysis covered residence, body mass index level, drinking status, and smoking status were conducted. The possible difference of associations between sexes was also explored. Results: With a total of 3,055 people, the hemoglobin concentration in people without sarcopenia, possible sarcopenia, and sarcopenia are 14.34 ± 2.22, 14.64 ± 2.27, and 13.58 ± 2.02 g/dl, respectively. Cross-sectional analysis showed strong evidence that hemoglobin was negatively associated with sarcopenia [Odds Ratio (OR) = 0.95, 95% Confidence Interval (CI): 0.90–0.99] and low height-adjusted appendicular skeletal muscle mass (OR = 0.91, 95% CI: 0.86–0.97). On average, a per 1 g/dl higher hemoglobin level was associated with 5% lower odds of sarcopenia (OR = 0.95, 95% CI: 0.90–0.98). The cohort study of 1,022 people demonstrated a statistically significant negative association of hemoglobin level with low physical performance [Hazard Ratio (HR) = 0.92, 95% CI: 0.85–0.99], merely with sarcopenia (HR = 0.92, 95% CI: 0.84–1.00) and skeletal muscle mass (HR = 0.95, 95% CI: 0.80–1.00). Sex-specific analysis suggested hemoglobin's association with sarcopenia, muscle mass, and physical performance in all sexes, with weaker magnitudes in females. Hemoglobin in urban residents and people with high body mass index (BMI) has a larger magnitude of the negative association with sarcopenia. Discussion: Hemoglobin level associates with sarcopenia, muscle mass, and physical performance in the Chinese population aged 60 and above, with sex-specific, residence-specific, and BMI-specific effects

Hyperbaric oxygen preconditioning for prevention of acute high-altitude diseases: fact or fiction?

Acute high-altitude diseases, including acute mountain sickness (AMS), high-altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE), have been recognized as potentially lethal diseases for altitude climbers. Various preconditioning stimuli, including hyperbaric oxygen (HBO), have been proposed to prevent acute high-altitude diseases. Herein, we reviewed whether and how HBO preconditioning could affect high-altitude diseases and summarized the results of current trials. Evidence suggests that HBO preconditioning may be a safe and effective preventive method for acute high-altitude diseases. The proposed mechanisms of HBO preconditioning in preventing high-altitude diseases may involve: 1) protection of the blood-brain barrier and prevention of brain edema, 2) inhibition of the inflammatory responses, 3) induction of the hypoxia-inducible factor and its target genes, and 4) increase in antioxidant activity. However, the optimal protocol of HBO preconditioning needs further exploration. Translating the beneficial effects of HBO preconditioning into current practice requires the “conditioning strategies” approach. More large-scale and high-quality randomized controlled studies are needed in the future

An overview of hyperbaric oxygen preconditioning against ischemic stroke

Ischemic stroke (IS) has become the second leading cause of morbidity and mortality worldwide, and the prevention of IS should be given high priority. Recent studies have indicated that hyperbaric oxygen preconditioning (HBO-PC) may be a protective nonpharmacological method, but its underlying mechanisms remain poorly defined. This study comprehensively reviewed the pathophysiology of IS and revealed the underlying mechanism of HBO-PC in protection against IS. The preventive effects of HBO-PC against IS may include inducing antioxidant, anti-inflammation, and anti-apoptosis capacity; activating autophagy and immune responses; upregulating heat shock proteins, hypoxia-inducible factor-1, and erythropoietin; and exerting protective effects upon the blood-brain barrier. In addition, HBO-PC may be considered a safe and effective method to prevent IS in combination with stem cell therapy. Although the benefits of HBO-PC on IS have been widely observed in recent research, the implementation of this technique is still controversial due to regimen differences. Transferring the results to clinical application needs to be taken carefully, and screening for the optimal regimen would be a daunting task. In addition, whether we should prescribe an individualized preconditioning regimen to each stroke patient needs further exploration

Knee osteoarthritis pendulum therapy : in vivo evaluation and a randomised, single-blind feasibility clinical trial

Background. Exercise is recommended as the first-line management for knee osteoarthritis (KOA); however, it is difficult to determine which specific exercises are more effective. This study aimed to explore the potential mechanism and effectiveness of a leg-swinging exercise practiced in China, called ‘KOA pendulum therapy’ (KOAPT). Intraarticular hydrostatic and dynamic pressure (IHDP) are suggested to partially explain the signs and symptoms of KOA. As such this paper set out to explore this mechanism in vivo in minipigs and in human volunteers alongside a feasibility clinical trial. The objective of this study is 1) to analyze the effect of KOAPT on local mechanical and circulation environment of the knee in experimental animals and healthy volunteers; and 2) to test if it is feasible to run a large sample, randomized/single blind clinical trial. Methods. IHDP of the knee was measured in ten minipigs and ten volunteers (five healthy and five KOA patients). The effect of leg swinging on synovial blood flow and synovial fluid content depletion in minipigs were also measured. Fifty KOA patients were randomly divided into two groups for a feasibility clinical trial. One group performed KOAPT (targeting 1000 swings/leg/day), and the other performed walking exercise (targeting 4000 steps/day) for 12 weeks with 12 weeks of follow-up. Results. The results showed dynamic intra-articular pressure changes in the knee joint, increases in local blood flow, and depletion of synovial fluid contents during pendulum leg swinging in minipigs. The intra-articular pressure in healthy human knee joints was −11.32 ± 0.21 (cmH2O), whereas in KOA patients, it was −3.52 ± 0.34 (cmH2O). Measures were completed by 100% of participants in all groups with 95–98% adherence to training in both groups in the feasibility clinical trial. There were significant decreases in the Oxford knee score in both KOAPT and walking groups after intervention (p < 0.01), but no significant differences between the two groups. Conclusion. We conclude that KOAPT exhibited potential as an intervention to improve symptoms of KOA possibly through a mechanism of normalising mechanical pressure in the knee; however, optimisation of the method, longer-term intervention and a large sample randomized-single blind clinical trial with a minimal 524 cases are needed to demonstrate whether there is any superior benefit over other exercises

A single amino acid substitution confers enhanced methylation activity of mammalian Dnmt3b on chromatin DNA

Dnmt3a and Dnmt3b are paralogous enzymes responsible for de novo DNA methylation but with distinguished biological functions. In mice, disruption of Dnmt3b but not Dnmt3a causes global DNA hypomethylation, especially in repetitive sequences, which comprise the large majority of methylated DNA in the genome. By measuring DNA methylation activity of Dnmt3a and Dnmt3b homologues from five species, we found that mammalian Dnmt3b possessed significantly higher methylation activity on chromatin DNA than Dnmt3a and non-mammalian Dnmt3b. Sequence comparison and mutagenesis experiments identified a single amino acid substitution (I662N) in mammalian Dnmt3b as being crucial for its high chromatin DNA methylation activity. Further mechanistic studies demonstrated this substitution markedly enhanced the binding of Dnmt3b to nucleosomes and hence increased the chromatin DNA methylation activity. Moreover, this substitution was crucial for Dnmt3b to efficiently methylate repetitive sequences, which increased dramatically in mammalian genomes. Consistent with our observation that Dnmt3b evolved more rapidly than Dnmt3a during the emergence of mammals, these results demonstrated that the I662N substitution in mammalian Dnmt3b conferred enhanced chromatin DNA methylation activity and contributed to functional adaptation in the epigenetic system

Antiproliferative Evaluation of Novel 4-Imidazolidinone Derivatives as Anticancer Agent Which Triggers ROS-Dependent Apoptosis in Colorectal Cancer Cell

Colorectal cancer (CRC) is one of the most common causes of cancer-related death worldwide, and more therapies are needed to treat CRC. To discover novel CRC chemotherapeutic molecules, we used a series of previously synthesized novel imidazolidin-4-one derivatives to study their anticancer role in several cancer cell lines. Among these compounds, compound 9r exhibited the best anticancer activity in CRC cell lines HCT116 and SW620. We further investigated the anticancer molecular mechanism of compound 9r. We found that compound 9r induced mitochondrial pathway apoptosis in HCT116 and SW620 cells by inducing reactive oxygen species (ROS) production. Moreover, the elevated ROS generation activated the c-Jun N-terminal kinase (JNK) pathway, which further accelerated apoptosis. N-acetylcysteine (NAC), an antioxidant reagent, suppressed compound 9r-induced ROS production, JNK pathway activation, and apoptosis. Collectively, this research synthesized a series of imidazolidin-4-one derivatives, evaluated their anticancer activity, and explored the molecular mechanism of compound 9r-induced apoptosis in CRC cells. The present results suggest that compound 9r has a potential therapeutic role in CRC. Hence, it deserves further exploration as a lead compound for CRC treatment