Role and Mechanism of Epigenetic Regulation in the Aging of Germ Cells: Prospects for Targeted Interventions.

In modern times, a notable trend toward delayed childbearing has been observed in most developed countries. As a result, sperm aging and quality loss, as well as premature ovarian failure (POF), have emerged as major causes of infertility. The pathogenesis of sperm aging and POF is complex and has not been clearly elucidated. However, evidence from some studies has linked germ cell aging to epigenetic modifications. Epigenetics refers to the heritable changes in gene expression that occur in the absence of any alterations to the gene's nucleotide sequence. This paper systematically reviewed and analyzed the relevant literature to describe the relationship of DNA methylation, non-coding RNA regulation, histone modifications, chromatin remodeling, and RNA modifications with sperm aging and POF. In addition, we analyzed how sperm aging and POF can be mitigated via epigenetic interventions. This review could provide new therapeutic insights and guide strategies for improving sperm quality and ovarian function.

Post-Translational Modification of MRE11: Its Implication in DDR and Diseases.

Maintaining genomic stability is vital for cells as well as individual organisms. The meiotic recombination-related gene MRE11 (meiotic recombination 11) is essential for preserving genomic stability through its important roles in the resection of broken DNA ends, DNA damage response (DDR), DNA double-strand breaks (DSBs) repair, and telomere maintenance. The post-translational modifications (PTMs), such as phosphorylation, ubiquitination, and methylation, regulate directly the function of MRE11 and endow MRE11 with capabilities to respond to cellular processes in promptly, precisely, and with more diversified manners. Here in this paper, we focus primarily on the PTMs of MRE11 and their roles in DNA response and repair, maintenance of genomic stability, as well as their association with diseases such as cancer.

Impact of Physicians' Personalities and Behavioral Traits on Treatment-Related Decision-making for Elderly Acute Myeloid Leukemia.

BACKGROUND: Elderly patients with acute myeloid leukemia (AML) can be treated with intensive therapy, low-intensity therapy, or best supportive care. Medical decision-making might be affected by physicians' occupational and non-occupational factors. OBJECTIVE: To explore the impact of physicians' personalities and behavioral traits on treatment-related decision-making for elderly AML patients. DESIGN: A nationwide cross-sectional survey. PARTICIPANTS: Hematologists in mainland China (N = 529; response rate 64.5%). MAIN MEASURES: The medical decision-making for elderly AML patients was evaluated using 6 clinical vignettes. Hematologists' attitudes toward risk and uncertainty, Big Five personality traits, and decision-making styles were assessed using binary lottery choices and well-recognized self-report inventories. KEY RESULTS: The resulting binary regression model in predicting treatment intensity contained professional title group (OR = 0.012, 95% CI 0.001 to 0.136, P < 0.001), conscientiousness (OR = 0.336, 95% CI 0.121 to 0.932, P = 0.036), extraversion (OR = 0.403, 95% CI 0.166 to 0.974, P = 0.044), conscientiousness by title group (OR = 2.009, 95% CI 1.100 to 3.667, P = 0.023), and extraversion by title group (OR = 1.627, 95% CI 0.965 to 2.743, P = 0.068) as predictors of therapy intensity preference. Junior physicians with a higher level of extraversion (mean difference = 0.27; 95% CI 0.07 to 0.45; P = 0.009) or conscientiousness (mean difference = 0.19; 95% CI 0.01 to 0.36; P = 0.028) tended to prescribe more intensive therapy. Meanwhile, no significant correlation was found between physicians' personalities or behavioral traits and treatment-related decision-making in senior physicians. CONCLUSIONS: Physicians' personalities contribute to treatment-related decision-making for elderly AML patients, depending on the professional titles. More extravert or conscientious attending physicians tended to prescribe more intensive therapy. Meanwhile, the decisions made by chief and associate chief physicians were not impacted by their personal traits. Junior physicians should be aware of such potential influence when making medical decisions.

NBS1 interacts with Notch signaling in neuronal homeostasis.

NBS1 is a critical component of the MRN (MRE11/RAD50/NBS1) complex, which regulates ATM- and ATR-mediated DNA damage response (DDR) pathways. Mutations in NBS1 cause the human genomic instability syndrome Nijmegen Breakage Syndrome (NBS), of which neuronal deficits, including microcephaly and intellectual disability, are classical hallmarks. Given its function in the DDR to ensure proper proliferation and prevent death of replicating cells, NBS1 is essential for life. Here we show that, unexpectedly, Nbs1 deletion is dispensable for postmitotic neurons, but compromises their arborization and migration due to dysregulated Notch signaling. We find that Nbs1 interacts with NICD-RBPJ, the effector of Notch signaling, and inhibits Notch activity. Genetic ablation or pharmaceutical inhibition of Notch signaling rescues the maturation and migration defects of Nbs1-deficient neurons in vitro and in vivo. Upregulation of Notch by Nbs1 deletion is independent of the key DDR downstream effector p53 and inactivation of each MRN component produces a different pattern of Notch activity and distinct neuronal defects. These data indicate that neuronal defects and aberrant Notch activity in Nbs1-deficient cells are unlikely to be a direct consequence of loss of MRN-mediated DDR function. This study discloses a novel function of NBS1 in crosstalk with the Notch pathway in neuron development.

Anxiolytic Effect of Alcohol-Water Extracted Suanzaoren-Wuweizi Herb-Pair by Regulating ECS-BDNF-ERK Signaling Pathway Expression in Acute Restraint Stress Male Rats.

Herb-pairs are the basic units of composition in Chinese herbal formulae, where the bridge linking Chinese medicine and prescription consists of two Chinese medicine herbs. The Suanzaoren-Wuweizi herb-pair (SWHP) is commonly used as a sedative or tranquilizer. SWHP has been demonstrated to exert an antianxiety effect in animal models of anxiety. However, little information about its mechanism is available and the effects of SWHP have not been investigated. This study examined the effects of SWHP on ameliorating anxiety-like behaviors by regulating endocannabinoids system (ECS)-brain-derived neurotrophic factor (BDNF)-extracellular regulated protein kinases (ERK) signaling pathway expression, induced by restraint stress (RS) procedures. The antianxiety effects of SWHP on RS rats were then examined through the open-field test (OF) and the elevated plus maze test (EPM). The concentration of BNDF, ERK1/2, p-ERK1/2, cAMP-response element binding protein (CREB), and p-CREB expression in the prefrontal cortex and hippocampus of the rats was then measured by western blot. The number of positive cells of CB1 and CB2 in the rats' hippocampus CA1 region was measured by immunohistochemistry. These results gave compelling evidence that SWHP could modify anxiety-like behaviors of RS rats through regulation of the ECS-BDNF-ERK signaling pathway. Our study demonstrated that SWHP improved anxiety-like behaviors in RS rat models by regulating the ECS-BDNF-ERK signaling pathway. The findings indicate that SWHP may have a therapeutic application in the RS model of anxiety disorder, which proposes a potential new direction for research into anxiety disorders regarding mechanisms and the development of novel antianxiety drugs.

Combined prognostic value of the cancer stem cell markers CD47 and CD133 in esophageal squamous cell carcinoma.

BACKGROUND: Treatments based on the inhibition of pivotal signals of cancer stem cells (CSCs) are on a promising track. Recent studies have shown that targeting CSCs with broader immune-based therapeutic methods, for example, the anti-CD47 treatment, may serve as a more potent strategy for eliminating these intractable cells. We aimed to explore the prognostic effects of CD47/CD133 and the potential therapeutic significance of CD47 in esophageal squamous cell carcinoma (ESCC). METHODS: Immunohistochemistry was employed to identify the characteristics of CD47 and CD133 in 26 pairs of tumor tissues and adjacent non-tumor tissues and 136 ESCC tissues. Kaplan-Meier analysis and Cox proportional hazards models were built for estimating the prognostic values of CD47 and CD133 expression and their combined stemness index. Sphere formation assays were undertaken to explore the effects of CD47 inhibition on primary human ESCC CSCs. RESULTS: Results conclude that CD47 and CD133 expression is increased in tumor tissues as compared to adjacent non-tumor tissues. A positive correlation between CD47/CD133 expression and differentiation was found in 136 ESCC patients. Survival analysis indicated that patients with high CD47 or CD133 expression exhibited poor overall survival and progression-free survival (PFS). The combination of high CD47 and CD133 expression was a reliable independent prognostic factor for both OS (HR = 1.940, 95% CI = 1.399-2.690, P < 0.0001) and progression-free survival (HR = 1.883, 95% CI = 1.384-2.562, P < 0.0001). Notably, CD47+ CD133+ ESCC cells were observed to possess the characteristics of CSCs, and anti-CD47 treatment veritably eliminated the CSCs pool. CONCLUSIONS: The stemness index determined by the expression of CD47 and CD133 is a promising prognostic predictor, and CD47 is a potential therapeutic target for CSCs in ESCC patients.

Identification of Bioactive Chemical Markers in Zhi zhu xiang Improving Anxiety in Rat by Fingerprint-Efficacy Study.

Zhi zhu xiang (ZZX for short) is the root and rhizome of Valeriana jatamansi Jones, which is a Traditional Chinese Medicine (TCM) used to treat various mood disorders for more than 2000 years, especially anxiety. The aim of the present work was to identify the bioactive chemical markers in Zhi zhu xiang improving anxiety in rats by a fingerprint-efficacy study. More specifically, the chemical fingerprint of ZZX samples collected from 10 different regions was determined by High Performance Liquid Chromatography (HPLC) and the similarity analyses were calculated based on 10 common characteristic peaks. The anti-anxiety effect of ZZX on empty bottle stimulated rats was examined through the Open Field Test (OFT) and the Elevated Plus Maze Test (EPM). Then we measured the concentration of CRF, ACTH, and CORT in rat's plasma by the enzyme-linked immune sorbent assay (ELISA) kit, while the concentration of monoamine and metabolites (NE, DA, DOPAC, HVA, 5-HT, 5-HIAA) in the rat's cerebral cortex and hippocampus was analysed by HPLC coupled with an Electrochemical Detector. At last, the fingerprint-efficacy study between chemical fingerprint and anti-anxiety effect of ZZX was accomplished by partial least squares regression (PLSR). As a result, we screened out four compounds (hesperidin, isochlorogenic acid A, isochlorogenic acid B and isochlorogenic acid C) as the bioactive chemical markers for the anti-anxiety effect of ZZX. The fingerprint-efficacy study we established might provide a feasible way and some elicitation for the identification of the bioactive chemical markers for TCM.

Diagnostic and prognostic roles of soluble CD22 in patients with Gram-negative bacterial sepsis.

BACKGROUND: Soluble CD22 (sCD22) is a fragment of CD22, a B cell-specific membrane protein that negatively regulates B-cell receptor signaling. To date, sCD22 has only been regarded as a tumor marker of B-cell malignancies. Its expression in infectious diseases has not yet been assessed. METHODS: Serum concentrations of sCD22, procalcitonin (PCT) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assays in patients with intra-abdominal Gram-negative bacterial infection. Receiver operating characteristic curve analysis was performed to evaluate the diagnostic accuracy of these biomarkers in this type of infection. The correlations between biomarkers and the Acute Physiology and Chronic Health Evaluation (APACHE) II scores were also analyzed. RESULTS: Concentrations of sCD22 were significantly elevated in patients with sepsis and the elevation is correlated with the severity of sepsis. sCD22 was also slightly elevated in patients with non-infected systemic inflammatory response syndrome or local infection. The diagnostic accuracy of sCD22 for sepsis was equivalent to that of PCT or IL-6. In addition, the correlation of sCD22 with APACHE II scores was stronger than that of PCT or IL-6. CONCLUSIONS: Serum sCD22 is a novel inflammatory mediator released during infection. This soluble biomarker plays a potential role in the diagnosis of Gram-negative bacterial sepsis, with a diagnostic accuracy as efficient as that of PCT or IL-6. Furthermore, sCD22 is more valuable to predict the outcomes in patients with sepsis than PCT or IL-6. The present study suggested that sCD22 might be potentially useful in supplementing current criteria for sepsis.

[Simultaneous separation of primary cardiomyocytes and cardiac fibroblasts from neonatal rats with density gradient centrifugation].

To improve a fast and high-quality isolation method for culturing the primary cardiomyocyte and fibroblast in vitro, the neonatal Wistar rats were decapitated accordingly and left ventricles were isolated under the sterile condition. The ventricles were chopped and digested in the enzyme solution containing 0.5 mg/mL type II collagenase. During this process, the digesting time, frequency and stirring speed, centrifuging frequency and speed were strictly controlled. The cardiomyocytes were separated from the cardiac fibroblast by using the Percoll density gradient centrifugation. The cell viability was tested by staining with 0.2% trypan blue. The purity of cardiomyocytes and fibroblasts were determined by immunoflourescent staining with anti-cTnI, anti-Vimentin and anti-α-SMA antibodies. The results indicated that with this protocol, the viability and purity of cardiomyocytes were 92% and 95%. The automobile pulse of the adhered cardiomyocyte was visible. For fibroblasts, the cell viability and purity were 96% and 94%. Our results demonstrate that this advanced isolation method is reproducible, and can simultaneously produce high-quality primary cardiomyocytes and fibroblasts for the future study.

GATA-2 inhibits transforming growth factor-ß signaling pathway through interaction with Smad4.

GATA-2, a member of zinc finger GATA transcription factor family, plays key role in the hematopoietic stem cells self-renewal and differentiation. The transforming growth factor-ß (TGFß) signaling pathway is a major signaling network that controls cell proliferation, differentiation and tumor suppression. Here we found that GATA-2 negatively regulated TGF-ß signaling pathway in Smad4-dependent manner. GATA-2 specifically interacts with Smad4 with its N-terminal while the zinc finger domain of GATA-2 is essential for negative regulation of TGFß. Although GATA-2 did not affect the phosphorylation of Smad2/3 and the complex Smad2/3/4 formation in response to TGFß, the DNA binding activity of Smad4 was decreased significantly by GATA-2 overexpression. Overexpression of GATA-2 in K562 cells led to reduced TGFß-induced erythroid differentiation while knockdown of GATA-2 enhanced TGFß-induced erythroid differentiation. All these results suggest that GATA-2 is a novel negative regulator of TGFß signal pathway.

[Post-traumatic stress disorder in convalescent patients of severe acute respiratory syndrome: (1)H-MRS study].

OBJECTIVE: To ascertain the metabolic changes in patients of severe acute respiratory syndrome (SARS) and SARS-related post-traumatic stress disorder (PTSD) and elucidate the relationship between PTSD, SARS and brain metabolism. METHODS: A total of 58 convalescent SARS patients were evaluated by the scores of impact of event scale (IES), self-rating anxiety scale (SAS) and self-rating depression scale (SDS), etc. And 44 of them participated in (1)H-MRS study. There were 18 patients (M:F = 6:12) with SARS-related PTSD and 26 convalescent SARS patients without PTSD. And the procedures were repeated in 18 age, gender and education-matched normal control subjects. In all patients and controls, the regions of interest on magnetic resonance spectroscopy (MRS) were anterior cingulate gyrus (ACG), posterior cingulate gyrus (PCG), left anterior periventricular white matter (LAPWM) and left posterior periventricular white matter (LPPWM). And the correlations between MRS findings and the scores of SAS, SDS and IES were evaluated. RESULTS: In comparisons with the control subjects (n = 18) and convalescent SARS patients without PTSD (n = 26), the SARS-related PTSD group (n = 18) had significantly lower N-acetylaspartate/creatine (NAA/Cr) in 4 regions of interest while the NAA/Cr of the convalescent SARS patients was significantly lower than controls in 3 regions of interest (ACG, PCG and LAPWM). The ratios of NAA/Cr showed no close correlation with the scores of IES, SAS and SDS in convalescent SARS patients. CONCLUSION: The changes of brain metabolism in PTSD are caused by SARS. But their exact relationship awaits further explorations. SARS may also lead to the changes of brain metabolism.

Molecular analysis of spring viraemia of carp virus in China: a fatal aquatic viral disease that might spread in East Asian.

Spring viraemia of carp (SVC) is a fatal viral disease for cyprinid fish, which is caused by spring viraemia of carp virus (SVCV). To date, no SVC outbreak has been reported in China. Between 1998 and 2002, outbreaks of SVC were reported in ornamental and wild fish in Europe and America, imported from multiple sources including China. Based on phylogenetic analysis, the viral strain isolated from America was shown to be originated from Asia. These outbreaks not only resulted in huge economic losses, but also raise an interesting question as to whether SVCV really exists in China and if so, is it responsible for SVC outbreaks? From 2002 to 2006, we screened 6700 samples from ornamental fish farms using the cell culture method of the Office International des Epizooties (OIE), and further verified the presence of SVCV by ELISA and real-time quantitative RT-PCR. Two infected samples were found and the complete genome of SVCV was sequenced from one of the isolates, termed SVCV-C1. Several unique hallmarks of SVCV-C1 were identified, including six amino acid (KSLANA) insertion in the viral RNA-dependent RNA polymerase (L) protein and ten nucleotide insertion in the region between glycoprotein (G) and L genes in European SVCV strains. Phylogenetic tree analysis of the full-length G protein of selected SVCV isolates from the United Kingdom and United States revealed that G proteins could be classified into Ia and Id sub genogroups. The Ia sub genogroup can be further divided into newly defined sub genogroups Ia-A and Ia-B. The isolates derived from the United States and China including the SVCV-C1 belongs to in the Ia-A sub genogroup. The SVCV-C1 G protein shares more than 99% homology with the G proteins of the SVCV strains from England and the United States, making it difficult to compare their pathogenicity. Comparison of the predicted three-dimensional structure based on the published G protein sequences from five SVCV strains revealed that the main differences were in the loops of the pleckstrin homology domains. Since SVCV is highly pathogenic, we speculate that SVC may therefore pose a serious threat to farmed cyprinid fish in China.