Construction of Near-Infrared Probes with Remarkable Large Stokes Shift Based on a Novel Purine Platform for the Visualization of mtG4 Upregulation during Mitochondrial Disorder in Somatic Cells and Human Sperms.

G-quadruplex structures within the nuclear genome (nG4) is an important regulatory factor, while the function of G4 in the mitochondrial genome (mtG4) still needs to be explored, especially in human sperms. To gain a better understanding of the relationship between mtG4 and mitochondrial function, it is crucial to develop excellent probes that can selectively visualize and track mtG4 in both somatic cells and sperms. Herein, based on our previous research on purine frameworks, we attempted for the first time to extend the conjugated structure from the C-8 site of purine skeleton and discovered that the purine derivative modified by the C-8 aldehyde group is an ideal platform for constructing near-infrared probes with extremely large Stokes shift (>220 nm). Compared with the compound substituted with methylpyridine (PAP), the molecule substituted with methylthiazole orange (PATO) showed better G4 recognition ability, including longer emission (∼720 nm), more significant fluorescent enhancement (∼67-fold), lower background, and excellent photostability. PATO exhibited a sensitive response to mtG4 variation in both somatic cells and human sperms. Most importantly, PATO helped us to discover that mtG4 was significantly increased in cells with mitochondrial respiratory chain damage caused by complex I inhibitors (6-OHDA and rotenone), as well as in human sperms that suffer from oxidative stress. Altogether, our study not only provides a novel ideal molecular platform for constructing high-performance probes but also develops an effective tool for studying the relationship between mtG4 and mitochondrial function in both somatic cells and human sperms.

Efficacy of high-fidelity simulation in advanced life support training: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Simulation is an increasingly used novel method for the education of medical professionals. This study aimed to systematically review the efficacy of high-fidelity (HF) simulation compared with low-fidelity (LF) simulation or no simulation in advanced life support (ALS) training. METHODS: A comprehensive search of the PubMed, Chinese Biomedicine Database, Embase, CENTRAL, ISI, and China Knowledge Resource Integrated Database was performed to identify randomized controlled trials (RCTs) that evaluated the use of HF simulation in ALS training. Quality assessment was based on the Cochrane Handbook for Systematic Reviews of Interventions version 5.0.1. The primary outcome was the improvement of knowledge and skill performance. The secondary outcomes included the participants' confidence and satisfaction at the course conclusion, skill performance at one year, skill performance in actual resuscitation, and patient outcomes. Data were synthesized using the RevMan 5.4 software. RESULTS: Altogether, 25 RCTs with a total of 1,987 trainees were included in the meta-analysis. In the intervention group, 998 participants used HF manikins, whereas 989 participants received LF simulation-based or traditional training (classical training without simulation). Pooled data from the RCTs demonstrated a benefit in improvement of knowledge [standardized mean difference (SMD) = 0.38; 95% confidence interval (CI): 0.18-0.59, P = 0.0003, I2 = 70%] and skill performance (SMD = 0.63; 95% CI: 0.21-1.04, P = 0.003, I2 = 92%) for HF simulation when compared with LF simulation and traditional training. The subgroup analysis revealed a greater benefit in knowledge with HF simulation compared with traditional training at the course conclusion (SMD = 0.51; 95% CI: 0.20-0.83, P = 0.003, I2 = 61%). Studies measuring knowledge at three months, skill performance at one year, teamwork behaviors, participants' satisfaction and confidence demonstrated no significant benefit for HF simulation. CONCLUSIONS: Learners using HF simulation more significantly benefited from the ALS training in terms of knowledge and skill performance at the course conclusion. However, further research is necessary to enhance long-term retention of knowledge and skill in actual resuscitation and patient's outcomes.

Loss-of-function CFTR p.G970D missense mutation might cause congenital bilateral absence of the vas deferens and be associated with impaired spermatogenesis.

Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.

[Latest Research Findings on Prediction of Preeclampsia in Pregnant Women Based on Analysis of Cell-Free RNA in Peripheral Blood].

Preeclampsia gravely threatens the health of mothers and infants. At present, treatment based on the relevant mechanisms of pathogenesis is still not available, and there is no independent reliable clinical index for early prediction of preeclampsia. According to recent studies, analysis of the cell-free RNA in the peripheral blood of pregnant women has shown that testing certain cell-free RNA levels can help predict in advance the occurrence of preeclampsia before clinical symptoms appear. In this paper, we described the status of research and progress in using maternal cell-free RNA analysis in predicting preeclampsia. In addition, we stated that cell-free RNA in peripheral blood may become a promising, real-time and non-invasive monitoring method that can be used to explore the mechanisms of pathogenesis and pathophysiology of preeclampsia and to identify different subtypes of preeclampsia.

Structures of the ADGRG2-Gs complex in apo and ligand-bound forms.

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.

LINC00461 Regulates the Recurrence of Large B Cell Lymphoma through the miR-411-5p/BNIP3 Pathway.

Objective: To analyze the mechanism of LINC00461 regulating the recurrence of diffuse large B cell lymphoma (DLBCL) through microRNA (miR)-411-5p/BCL2 interacting protein 3 (BNIP3) pathway. Methods: DLBCL samples in TCGA and GSE12453 were used for differential analysis to find long noncoding RNA (lncRNA) related to DLBCL recurrence. The 4 DLBCL data with the highest and lowest expression levels of LINC00461 in the TCGA database were selected for GSEA enrichment analysis. The targeting relationships of miR-411-5p with LINC00461 and BNIP3 were verified by the dual luciferase report. Blood samples from DLBCL patients were used to analyze the correlation between miR-411-5p and LINC00461 or BNIP3. LINC00461, miR-411-5p, or BNIP3 was overexpressed or silenced by transfection, and a tumor-bearing nude mice model was constructed to detect their effects on proliferation and apoptosis. Results: The level of LINC00461 in DLBCL was significantly higher than that in normal cases, and the level in recurrence DLBCL was significantly higher than that in nonrecurrence. The enrichment analysis results showed that the function of LINC00461 was closely related to apoptosis. The results shown that miR-411-5p bound to LINC00461 and BNIP3 and was negatively correlated with LINC00461 and BNIP3 mRNA in blood of DLBCL patients. Suppressing the level of LINC00461 inhibited cell proliferation and induced apoptosis. The inhibition of LINC00461 or overexpression of miR-411-5p reduced the expression of BNIP3 protein, thereby inducing apoptosis at the in vivo and in vitro levels. Conclusion: LINC00461 may induce miR-411-5p to "sponge," thereby increasing the expression of BNIP3 protein, and exerting the function of inhibiting apoptosis and promoting DLBCL recurrence.

Activation of PTH1R alleviates epididymitis and orchitis through Gq and ß-arrestin-1 pathways.

Inflammation in the epididymis and testis contributes significantly to male infertility. Alternative therapeutic avenues treating epididymitis and orchitis are expected since current therapies using antibiotics have limitations associated to side effects and are commonly ineffective for inflammation due to nonbacterial causes. Here, we demonstrated that type 1 parathyroid hormone receptor (PTH1R) and its endogenous agonists, parathyroid hormone (PTH) and PTH-related protein (PTHrP), were mainly expressed in the Leydig cells of testis as well as epididymal epithelial cells. Screening the secretin family G protein-coupled receptor identified that PTH1R in the epididymis and testis was down-regulated in mumps virus (MuV)- or lipopolysaccharide (LPS)-induced inflammation. Remarkably, activation of PTH1R by abaloparatide (ABL), a Food and Drug Administration-approved treatment for postmenopausal osteoporosis, alleviated MuV- or LPS-induced inflammatory responses in both testis and epididymis and significantly improved sperm functions in both mouse model and human samples. The anti-inflammatory effects of ABL were shown to be regulated mainly through the Gq and ß-arrestin-1 pathway downstream of PTH1R as supported by the application of ABL in Gnaq± and Arrb1-/- mouse models. Taken together, our results identified an important immunoregulatory role for PTH1R signaling in the epididymis and testis. Targeting to PTH1R might have a therapeutic effect for the treatment of epididymitis and orchitis or other inflammatory disease in the male reproductive system.

Associations between Huwe1 and autophagy in rat cerebral neuron oxygen­glucose deprivation and reperfusion injury.

Autophagy and the ubiquitin proteasome system (UPS) are two major protein degradation pathways involved in brain ischemia. Autophagy can compensate for UPS impairment­induced cellular dysfunction. HECT, UBA and WWE domain containing E3 ubiquitin protein ligase 1 (Huwe1), an E3 ubiquitin ligase, serves critical roles in nervous system plasticity, regeneration and disease. However, the role of Huwe1 in autophagy in brain ischemia/reperfusion (I/R) injury remains unknown. The aim of the present study was to investigate the crosstalk between autophagy and the UPS in brain ischemia. The present study established an oxygen­glucose deprivation and reperfusion (OGD/R) model in rat primary cortex neurons in vitro. Lentiviral interference was used to silence the expression of Huwe1. An autophagy promoter (rapamycin), an autophagy inhibitor (wortmannin) and a JNK pathway inhibitor (SP600125) were also used in the current study. Cellular autophagy­related proteins, including Beclin­1, autophagy related (ATG) 7, ATG5, ATG3 and microtubule associated protein 1 light chain 3 α, and apoptosis­related proteins, such as P53, cleaved caspase 3, Bax and Bcl2, were detected via western blotting and immunocytochemistry. Neuronal apoptosis was evaluated using a TUNEL assay. The results demonstrated that silencing Huwe1 increased the expression levels of autophagy­related proteins at 24 h after OGD/R. Treatment with a JNK inhibitor or cotreatment with Huwe1 shRNA significantly increased autophagy. Rapamycin increased apoptosis under OGD/R conditions. However, treatment with Huwe1 shRNA decreased the number of TUNEL­positive cells at 24 h after OGD/R. Cotreatment with Huwe1 shRNA and wortmannin alleviated neuronal apoptosis under OGD/R conditions compared with cotreatment with DMSO. Collectively, the present results suggested that silencing Huwe1 was accompanied by a compensatory induction of autophagy under OGD/R conditions. Furthermore, the JNK pathway may be a key mediator of the interaction between Huwe1 and autophagy in response to UPS impairment.

Silencing Huwe1 reduces apoptosis of cortical neurons exposed to oxygen-glucose deprivation and reperfusion.

HECT, UBA and WWE domain-containing 1 (Huwe1), an E3 ubiquitin ligase involved in the ubiquitin-proteasome system, is widely expressed in brain tissue. Huwe1 is involved in the turnover of numerous substrates, including p53, Mcl-1, Cdc6 and N-myc, thereby playing a critical role in apoptosis and neurogenesis. However, the role of Huwe1 in brain ischemia and reperfusion injury remains unclear. Therefore, in this study, we investigated the role of Huwe1 in an in vitro model of ischemia and reperfusion injury. At 3 days in vitro, primary cortical neurons were transduced with a control or shRNA-Huwe1 lentiviral vector to silence expression of Huwe1. At 7 days in vitro, the cells were exposed to oxygen-glucose deprivation for 3 hours and reperfusion for 24 hours. To examine the role of the c-Jun N-terminal kinase (JNK)/p38 pathway, cortical neurons were pretreated with a JNK inhibitor (SP600125) or a p38MAPK inhibitor (SB203508) for 30 minutes at 7 days in vitro, followed by ischemia and reperfusion. Neuronal apoptosis was assessed by TUNEL assay. Protein expression levels of JNK and p38MAPK and of apoptosis-related proteins (p53, Gadd45a, cleaved caspase-3, Bax and Bcl-2) were measured by western blot assay. Immunofluorescence labeling for cleaved caspase-3 was performed. We observed a significant increase in neuronal apoptosis and Huwe1 expression after ischemia and reperfusion. Treatment with the shRNA-Huwe1 lentiviral vector markedly decreased Huwe1 levels, and significantly decreased the number of TUNEL-positive cells after ischemia and reperfusion. The silencing vector also downregulated the pro-apoptotic proteins Bax and cleaved caspase-3, and upregulated the anti-apoptotic proteins Gadd45a and Bcl-2. Silencing Huwe1 also significantly reduced p-JNK levels and increased p-p38 levels. Our findings show that downregulating Huwe1 affects the JNK and p38MAPK signaling pathways as well as the expression of apoptosis-related genes to provide neuroprotection during ischemia and reperfusion. All animal experiments and procedures were approved by the Animal Ethics Committee of Sichuan University, China in January 2018 (approval No. 2018013).

Proteomics and single-cell RNA analysis of Akap4-knockout mice model confirm indispensable role of Akap4 in spermatogenesis.

Sperm fibrous sheath, a unique cytoskeletal structure, is implicated in various sperm physiological functions, such as sperm maturation, motility and capacitation. AKAP4 has been described to be required for structural and functional integrity of the fibrous sheath. We generated Akap4-knockout mice line using CRISPR-Cas9 system. Cytomorphology and motility of sperm and testes were studied, confirming loss of Akap4 led to abnormal sperm morphology, motility and infertility. The proteomic components of testes were studied and Akap4 was found to be significantly decreased in the Akap4-knockout mice. Testis single-cell RNA sequencing and analysis revealed three genes with significant change in the general cell population, i.e., Akap4, Haspin, and Ccdc38. The single-cell RNA expression profiles also showed that the major difference between Akap4-knockout and wild-type testes existed in the elongating cell cluster, where in the Akap4-knockout testes, a subgroup of elongating cells with marker genes involved in cell adhesion and migration were increased, while a subgroup of elongating cells marked by mitochondrial sheath genes were decreased. Our results revealed the complex and well-coordinated procedures of spermatogenesis, and substantiated Akap4's indispensable roles in the integrity of sperm flagellum and the step-wise maturation of spermatozoa.

p57KIP2­mediated inhibition of human trophoblast apoptosis and promotion of invasion in vitro.

Placental hypoxia serves a role in the early stages of normal pregnancy and is involved in the pathophysiology of preeclampsia. Previously, it was suggested that p57kinase inhibitory protein (KIP)2 regulates the cell cycle during embryogenesis and apoptosis. Recent evidence has indicated that p57KIP2 is increased in preeclamptic placentas and absence of p57KIP2 induces preeclampsia­type symptoms in rats. However, effects of p57KIP2 on apoptosis under hypoxic conditions remain to be elucidated. In the present study, HTR­8/SVneo trophoblasts were cultured under hypoxic conditions (2% O2). Knockdown using small interfering (si)RNA and overexpression of p57KIP2 were utilized to explore the biological function of p57KIP2 in apoptosis and cell function in vitro. Furthermore, expression of p57KIP2 and apoptosis were evaluated by western blotting, flow cytometry and TUNEL assays, and the response of trophoblasts to hypoxia and the role of p57KIP2 in trophoblast migration and invasion was assessed. The role of p57KIP2 in the JNK signaling pathway in HTR­8/SVneo trophoblasts was further studies. In vitro, protein expression of p57KIP2 was increased in HTR­8/SVneo cells exposed to 2% O2. Exogenous p57KIP2 overexpression significantly decreased the expression of pro­apoptosis proteins, including p53, Bax and cleaved caspase3, under hypoxic conditions for 24 h. In addition, knockdown of p57KIP2 increased the response to apoptosis following hypoxia for 24 h. The present study revealed that overexpression of p57KIP2 decreased the levels of phosphorylated­JNK. JNK inhibitor treatment combined with the overexpression of p57KIP2 significantly decreased the levels of apoptosis and increased cell invasion and migration. Taken together, p57KIP2 knockdown significantly increased apoptosis in HTR­8/SVneo cells exposed to 2% O2, whereas overexpression of p57KIP2 had opposite effects, mediated by the JNK/stress activated protein kinase (SAPK) signaling pathway. The results indicated that hypoxia­induced expression of p57KIP2 promoted trophoblast migration and invasion by mediating the JNK/SAPK signaling pathway, which is crucial during placentation. These results may provide a novel molecular mechanism to understand the involvement of p57KIP2 in the pathogenesis of preeclampsia.

[Interaction between glycogen synthase kinase-3ß and endoplasmic reticulum stress is involved in high glucose-induced injury in human umbilical vein endothelial cells].

OBJECTIVE: To explore the role of the interaction between glycogen synthase kinase-3ß (GSK-3ß) and endoplasmic reticulum stress (ERS) in the high glucose (HG)-induced injury in human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs treated with 40 mmol/L glucose for 24 h were examined for expression levels of GSK-3ß, GRP78, CHOP and cleaved caspase-3 protein using Western blotting. The cell viability was examined using CCK-8 assay and cell apoptosis was detected with Hoechst 33258 nuclear staining and photofluorography. The intracellular level of reactive oxygen species (ROS) was measured with dichlorfluoresein staining and photofluorography. Mitochondrial membrane potential (MMP) was tested by rhodamine 123 (Rh123) staining and photofluorography. RESULTS: Treatment of HUVECs with 40 µmol/L glucose for 3-24 h activated GSK-3ß in a time-dependent manner, leading to significantly down-regulated expression of phosphorylated (p)-GSK-3ß (P<0.05). HG exposure of the cells for 1-24 h induced ERS, evidenced by time-dependently up-regulated expression of GRP78 and CHOP (P<0.05). LiCl, an inhibitor of GSK-3ß, attenuated HG-induced ERS and significantly lowered the expression levels of GRP78 and CHOP (P<0.01). 4-PBA, an inhibitor of ERS, obviously ameliorated the activation of GSK-3ß by HG as shown by the increase in p-GSK-3ß expression level (P<0.01). HG exposure for 24 h induced obvious injuries in HUVECs, which exhibited decreased cell viability, increased cell apoptosis, increased expression of cleaved caspase-3 and ROS generation, and loss of MMP. Pretreatment of the cells with LiCl or 4-PBA for 60 min before HG exposure significantly lessened the cell injuries (P<0.01). CONCLUSION: Interactions between GSK-3ß and ERS occur in HUVECs exposed to HG and participate in HG-induced cell injuries.

Bisphenol A Initiates Excessive Premature Activation of Primordial Follicles in Mouse Ovaries via the PTEN Signaling Pathway.

The essence of primary ovarian insufficiency (POI) is the premature exhaustion of primordial follicles in the follicle pool, which is caused by the excessive premature activation of primordial follicles after birth. Bisphenol A (BPA) exposure promotes the transition of primordial follicles to primary follicles, thus the number of primordial follicles in the primordial follicle pool decreases significantly. However, the molecular mechanisms underlying abnormal follicle activation are poorly understood. Phosphatase and tensin homologue (PTEN) signal system is a negative regulator of follicle activation, which is called the brake of follicle activation. Besides, BPA induces Michigan Cancer Foundation-7 breast cancer cells proliferation by dysregulating PTEN/serine/threonine kinase/p53 axis. Whether BPA initiates the excessive premature activation of primordial follicles in the mouse ovaries via PTEN signaling pathway is unclear. In this study, we treated 6-week-old female CD-1 mice with different concentrations of BPA to study the effect of BPA on follicular activation and development in vivo, as well as the role of PTEN signaling in this process. We observed that BPA in concentrations from 1 µg/kg to 10 mg/kg groups downregulated PTEN expression and initiated excessive premature activation of primordial follicles in the mouse ovaries, and this effect was partly reversible by PTEN overexpression. Our results improve the understanding of both the effect of BPA in occurrence of POI and molecular mechanisms underlying initiation of primordial follicle pool activation, thus providing insight for POI treatment and theoretical basis for reducing the risk of POI.

[The Association Between the Polymorphisms of miRNA Biogenesis Related Genes(DICER,DROSHA and RAN)and Unexplained Recurrent Spontaneous Abortion in Chinese Women].

OBJECTIVE: To explore the association between polymorphisms of miRNA biogenesis related gene DICER,DROSHA,RAN and unexplained recurrent spontaneous abortion (URSA) in Chinese women. METHODS: We recruited 217 patients with URSA (URSA group) and 390 healthy controls who were fertile women with history of more than one successful pregnancy outcome (control group) from June 2013 to December 2015 in the West China Second University Hospital of Sichuan University. The control group was recruited from regular physical examination and prepregnancy check for women of childbearing age during the same period. A case-control study was performed to analyze polymorphism of miRNA machinery genes,including DICER rs3742330,DROSHA rs10719, RAN rs14035,by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. RESULTS: The frequencies of genotypes and alleles of DICER rs3742330,DROSHA rs10719,and RAN rs14035 showed no difference between URSA patients and control group (all P>0.05). DICER rs3742330/DROSHA rs10719 GG/TC+TT combinations were synergistically associated with increased URSA risk [odds ratio (OR)=1.657,95% confidence interval (CI)=1.006-2.731, P=0.047]. Although DICER rs3742330/RAN rs14035 GG / TT+TC combinations was significantly higher in the URSA group than in the control group,there was no statistical significance (OR=1.977,95%CI=0.956-4.087, P=0.066). However,DROSHA10719/RAN14035 TT+TC/TT+TC had no significant correlation with URSA (OR=0.958,95%CI=0.679-1.353, P=0.808). CONCLUSION: Our study demonstrated the relationship between URSA development and combined genotype of DICER rs3742330/DROSHA rs10719 GG/TC+TT.

Research advances of Dicer in regulating reproductive function.

Dicer, an RNAse III endonuclease, is critical for the biogenesis of small noncoding RNAs (microRNAs), including the biogenesis of microRNAs and small interfering RNAs, which transcriptionally and post-transcription ally regulate mRNA expression through binding to target mRNA and leading to subsequent mRNA degradation. Recent studies show that Dicer plays important roles in cell proliferation, differentiation and apoptosis. It has been attracted more and more attention in the reproductive field. In the male reproduction field, mouse model shows that Dicer is critical for the development of spermatogenic cell, sperm maturation, sperm motility and morphology. On the other hand, Dicer is broadly involved in not only follicular development, ovulation, luteinization, sex hormone synthesis, but also regulating the functions of the fallopian tube, endometrial receptivity in female reproduction. Since sperm and egg are the only two types of gametes for producing offspring, Dicer dysregulation may be the underlying cause of compromised embryo development through affecting the quantity or quality of sperm and eggs. Therefore, understanding the function of Dicer in reproduction of female and male is of great significance to study the pathogenetic mechanism related to dysfunctional reproduction, such as azoospermia and recurrent spontaneous abortion. We review the pivotal roles of Dicer in the male and female reproduction field in order to understand the relationship between Dicer and related disease.

Huwe1 interacts with Gadd45b under oxygen-glucose deprivation and reperfusion injury in primary Rat cortical neuronal cells.

BACKGROUND: Growth arrest and DNA-damage inducible protein 45 beta (Gadd45b) is serving as a neuronal activity sensor. Brain ischemia induces the expression of Gadd45b, which stimulates recovery after stroke and may play a protective role in cerebral ischemia. However, little is known of the molecular mechanisms of how Gadd45b expression regulated and the down-stream targets in brain ischemia. Here, using an oxygen-glucose deprivation and reperfusion (OGD/R) model, we identified Huwe1/Mule/ARF-BP1, a HECT domain containing ubiquitin ligase, involved in the control of Gadd45b protein level. In this study, we also investigated the role of Huwe1-Gadd45b mediated pathway in BDNF methylation. RESULTS: We found that the depletion of Huwe1 by lentivirus shRNA mediated interference significantly increased the expression of Gadd45b and BDNF at 24 h after OGD. Moreover, treatment with Cycloheximide (CHX) inhibited endogenous expression of Gadd45b, and promoted expression of Gadd45b after co-treated with lentivirus shRNA-Huwe1. Inhibition of Gadd45b by lentivirus shRNA decreased the expression levels of brain derived neurotrophic factor (BDNF) and phosphorylated cAMP response element-binding protein (p-CREB) pathway, while inhibition of Huwe1 increased the expression levels of BDNF and p-CREB. Moreover, shRNA-Huwe1 treatment decreased the methylation level of the fifth CpG islands (123 bp apart from BDNF IXa), while shRNA-Gadd45b treatment increased the methylation level of the forth CpG islands (105 bp apart from BDNF IXa). CONCLUSIONS: These findings suggested that Huwe1 involved in the regulation of Gadd45b expression under OGD/R, providing a novel route for neurons following cerebral ischemia-reperfusion injury. It also indicated that the methylation of BDNF IXa was affected by Gadd45b as well as Huwe1 in the OGD/R model.

Polyethylene glycol modification decreases the cardiac toxicity of carbonaceous dots in mouse and zebrafish models.

AIM: Carbonaceous dots (CDs), which have been used for diagnosis, drug delivery and gene delivery, are accumulated in heart at high concentrations. To improve their biocompatibility, polyethylene glycol-modified CDs (PEG-CDs) were prepared. In this study we compared the cardiac toxicity of CDs and PEG-CDs in mouse and zebrafish models. METHODS: Mice were intravenously treated with CDs (size: 4.9 nm, 5 mg·kg(-1)·d(-1)) or PEG-CDs (size: 8.3 nm, 5 mg·kg(-1)·d(-1)) for 21 d. Their blood biochemistry indices, ECG, and histological examination were examined for evaluation of cardiac toxicity. CDs or PEG-CDs was added in incubator of cmlc2 transgenic Zebrafish embryos at 6 hpf, and the shape and size of embryos' hearts were observed at 48 hpf using a fluorescent microscope. Furthermore, whole-mount in situ hybridization was used to examine the expression of early cardiac marker gene (clml2) at 48 hpf. RESULTS: Administration of CDs or PEG-CDs in mice caused mild, but statistically insignificant reduction in serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels detected at 7 d, which were returned to the respective control levels at 21 d. Neither CDs nor PEG-CDs caused significant changes in the morphology of heart cells. Administration of CDs, but not PEG-CDs, in mice caused marked increase of heart rate. Both CDs and PEG-CDs did not affect other ECG parameters. In the zebrafish embryos, addition of CDs (20 µg/mL) caused heart development delay, whereas addition of CDs (80 µg/mL) led to heart malformation. In contrast, PEG-CDs caused considerably small changes in heart development, which was consistent with the results from the in situ hybridization experiments. CONCLUSION: CDs causes greater cardiac toxicity, especially regarding heart development. Polyethylene glycol modification can attenuate the cardiac toxicity of CDs.

[Roles of miR-15b in endothelial cell function and their relevance to vascular diseases].

MicroRNAs (miRNAs) are noncoding RNAs with a short length of about 22 nucleotides. As major modulators participating in RNA interference, they affect cellular behaviors by regulating the expression of diverse genes at post-transcriptional levels. miR-15b is a member of the miR-15/16 family, which is broadly expressed in major tissues and specially enriched in the endovascular system of human beings. miR-15/16 affects cellular proliferation, apoptosis, invasion and angiogenesis. In this review, we summarize the role and the underlying mechanism of miR-15b as well as other miR-15/16 family members in different cells, especially in endothelial cells. We focus on the diverse roles of miR-15b in the occurrence, progression and prognosis of vascular diseases, with particular emphasis on preeclampsia, a hypertensive disorder related to endovascular dysfunction in the placenta.

The serum glucan level and pathological changes of antifungal treatment for lower respiratory tract infection of Candida albicans.

Due to the fact that Candida albicans colonizes in the upper respiratory tracts of healthy people, whether or not its isolation from airway secretions is sufficient to warrant treatment remains controversial. The animal models of immunosuppressive rats with pulmonary candidiasis were established by the intratracheal inoculating suspensions of C. albicans, and the animals were divided into the following three groups: (1) antifungal treatment group, (2) saline control group, and (3) blank control group. We noted the following in our studies: (1) The fungal load of the saline control group gradually increased such that it was higher than those of the antifungal treated group and was significant from the fourth day of treatment (P < 0.01). (2) The serum (1,3)-ß-D-glucan (BG) in the saline control group also gradually increased so that it was significantly higher than found with the treated group by the sixth day of treatment (P < 0.05), and in fact, the rank of pulmonary colony count and BG in the two groups at different time points showed an almost perfect linear correlation. (3) The median survival period of the rats in the antifungal treated group and saline control group was 15 and 8 days respectively, no rats died in the blank control group. (4) The lung lesions from the saline control group gradually became more aggravated than those in the antifungal treated group; no significant pathological changes were found in the blank control group. Antifungal treatment (micafungin) is capable of efficaciously decreasing the lung fungal burden, and continuous monitoring of BG is useful for the evaluation of therapeutic effect of antifungals. Infection of C. albicans with associated pathological damage implies the need for antifungal therapy.