HDAC3 promotes Sertoli cell maturation and maintains the blood-testis barrier dynamics.

Germ cell development depends on the capacity of somatic Sertoli cells to undergo differentiation into a mature state and establish a germ cell-specific blood-testis barrier (BTB). The BTB structure confers an immunological barrier for meiotic and postmeiotic germ cells, and its dynamic permeability facilitates a transient movement of preleptotene spermatocytes through BTB to enter meiosis. However, the regulatory factors involved in Sertoli cell maturation and how BTB dynamics coordinate germ cell development remain unclear. Here, we found a histone deacetylase HDAC3 abundantly expresses in Sertoli cells and localizes in both cytoplasm and nucleus. Sertoli cell-specific Hdac3 knockout in mice causes infertility with compromised integrity of blood-testis barrier, leading to germ cells unable to traverse through BTB and an accumulation of preleptotene spermatocytes in juvenile testis. Mechanistically, nuclear HDAC3 regulates the expression program of Sertoli cell maturation genes, and cytoplasmic HDAC3 forms a complex with the gap junction protein Connexin 43 to modulate the BTB integrity and dynamics through regulating the distribution of tight junction proteins. Our findings identify HDAC3 as a critical regulator in promoting Sertoli cell maturation and maintaining the homeostasis of the blood-testis barrier.

Retracted: Expression of TP53, BCL-2, and VEGFA Genes in Esophagus Carcinoma and its Biological Significance.

The Editors of Medical Science Monitor wish to inform you that the above manuscript has been retracted from publication due to concerns with the credibility and originality of the study, the manuscript content, and the Figure images. Reference: Wei Wei, Yanqin Wang, Xiaoming Yu, Lan Ye, Yuhua Jiang, Yufeng Cheng. Expression of TP53, BCL-2, and VEGFA Genes in Esophagus Carcinoma and its Biological Significance. Med Sci Monit, 2015; 21: 3016-3022. DOI: 10.12659/MSM.894640.

A Workflow for Meaningful Interpretation of Classification Results from Handheld Ambient Mass Spectrometry Analysis Probes.

While untargeted analysis of biological tissues with ambient mass spectrometry analysis probes has been widely reported in the literature, there are currently no guidelines to standardize the workflows for the experimental design, creation, and validation of molecular models that are utilized in these methods to perform class predictions. By drawing parallels with hurdles that are faced in the field of food fraud detection with untargeted mass spectrometry, we provide a stepwise workflow for the creation, refinement, evaluation, and assessment of the robustness of molecular models, aimed at meaningful interpretation of mass spectrometry-based tissue classification results. We propose strategies to obtain a sufficient number of samples for the creation of molecular models and discuss the potential overfitting of data, emphasizing both the need for model validation using an independent cohort of test samples, as well as the use of a fully characterized feature-based approach that verifies the biological relevance of the features that are used to avoid false discoveries. We additionally highlight the need to treat molecular models as "dynamic" and "living" entities and to further refine them as new knowledge concerning disease pathways and classifier feature noise becomes apparent in large(r) population studies. Where appropriate, we have provided a discussion of the challenges that we faced in our development of a 10 s cancer classification method using picosecond infrared laser mass spectrometry (PIRL-MS) to facilitate clinical decision-making at the bedside.

[Relationship between serum 25-hydroxyvitamin D and handgrip strength in middle-aged and elderly people in five cities of Western China].

OBJECTIVE: To explore the association between serum 25-hydroxyvitamin D [25(OH)D] and handgrip strength in middle-aged and elderly people in 5 cities of Western China. METHODS: Based on the data of a cross-sectional survey conducted in the 5 cities of Western China from February to July 2023, the relevant demographic characteristics of people were collected by questionnaire, handgrip strength was collected by physical examination, and serum 25(OH)D was detected by HPLC-MS/MS. The association between the serum 25(OH)D and handgrip strength was analyzed using Logistic regression and Chi-square test for between-group comparisons models. RESULTS: The prevalence of 25(OH)D deficiency and insufficiency among the middle-aged and elderly people in the 5 cities of Western China was 52.9% and 34.5%, respectively. The people who were older, female, and sampled in winter had lower serum 25(OH)D levels (P < 0.05). The prevalence of loss of handgrip strength among the middle-aged and elderly people was 25.3%. The prevalence of handgrip strength loss was higher in the aged 65-80 participants with 25(OH)D deficiency (45. 0%) than in those with 25(OH)D insufficiency (32.6%) and 25(OH)D sufficiency (20.6%). The highest prevalence of loss of handgrip strength was found in the aged 75-80 participants with 25(OH)D deficiency (62. 1%), followed by the 25(OH)D insufficient group (11.1%, P < 0.05). The study found that middle-aged and elderly people with 25(OH)D deficiency had a 1.4-fold increased risk of handgrip strength loss compared with those with 25(OH)D sufficiency (OR=2.403, 95%CI: 1.202-4.804, P=0.013). No significant association was found between 25(OH)D insufficiency and handgrip strength status in the middle-aged and elderly people. For every 5 µg/L increase in total serum 25(OH)D, the risk of handgrip strength loss reduced by 13.1% (OR=0.869, 95%CI: 0.768-0.982, P=0.025). For every 5 µg/L increase in serum 25(OH)D2, the risk of handgrip strength loss reduced by 24.1% (OR=0.759, 95%CI: 0.582-0.990, P=0.042). No significant association was found between serum 25(OH)D3 levels and the risk of handgrip strength loss. The risk of handgrip strength loss in middle-aged and elderly people was reduced by 25.2% for each incremental increase in the total serum 25(OH)D levels (deficient, insufficient and sufficient) (OR=0.748, 95%CI: 0.598-0.936, P=0.011). The risk of handgrip loss was reduced by 40.0% for each incremental increase in serum 25(OH)D levels in the aged 65-80 and aged 65-69 participants, and by 80.0% for each incremental increase in 25(OH)D levels in the aged 75-80 parti-cipants. CONCLUSION: Serum total 25(OH)D and 25(OH)D2 levels are associated with handgrip strength status in middle-aged and elderly people in the 5 cities of Western China.

Metabolic Lipids in Melanoma Enable Rapid Determination of Actionable BRAF-V600E Mutation with Picosecond Infrared Laser Mass Spectrometry in 10 s.

Rapid molecular profiling of biological tissues with picosecond infrared laser mass spectrometry (PIRL-MS) has enabled the detection of clinically important histologic types and molecular subtypes of human cancers in as little as 10 s of data collection and analysis time. Utilizing an engineered cell line model of actionable BRAF-V600E mutation, we observed statistically significant differences in 10 s PIRL-MS molecular profiles between BRAF-V600E and BRAF-wt cells. Multivariate statistical analyses revealed a list of mass-to-charge (m/z) values most significantly responsible for the identification of BRAF-V600E mutation status in this engineered cell line that provided a highly controlled testbed for this observation. These metabolites predicted BRAF-V600E expression in human melanoma cell lines with greater than 98% accuracy. Through chromatography and tandem mass spectrometry analysis of cell line extracts, a 30-member "metabolite array" was characterized for determination of BRAF-V600E expression levels in subcutaneous melanoma xenografts with an average sensitivity and specificity of 95.6% with 10 s PIRL-MS analysis. This proof-of-principle work warrants a future large-scale study to identify a metabolite array for 10 s determination of actionable BRAF-V600E mutation in human tissue to guide patient care.

HDAC3 controls male fertility through enzyme-independent transcriptional regulation at the meiotic exit of spermatogenesis.

The transition from meiotic spermatocytes to postmeiotic haploid germ cells constitutes an essential step in spermatogenesis. The epigenomic regulatory mechanisms underlying this transition remain unclear. Here, we find a prominent transcriptomic switch from the late spermatocytes to the early round spermatids during the meiotic-to-postmeiotic transition, which is associated with robust histone acetylation changes across the genome. Among histone deacetylases (HDACs) and acetyltransferases, we find that HDAC3 is selectively expressed in the late meiotic and early haploid stages. Three independent mouse lines with the testis-specific knockout of HDAC3 show infertility and defects in meiotic exit with an arrest at the late stage of meiosis or early stage of round spermatids. Stage-specific RNA-seq and histone acetylation ChIP-seq analyses reveal that HDAC3 represses meiotic/spermatogonial genes and activates postmeiotic haploid gene programs during meiotic exit, with associated histone acetylation alterations. Unexpectedly, abolishing HDAC3 catalytic activity by missense mutations in the nuclear receptor corepressor (NCOR or SMRT) does not cause infertility, despite causing histone hyperacetylation as HDAC3 knockout, demonstrating that HDAC3 enzyme activity is not required for spermatogenesis. Motif analysis of the HDAC3 cistrome in the testes identified SOX30, which has a similar spatiotemporal expression pattern as HDAC3 during spermatogenesis. Depletion of SOX30 in the testes abolishes the genomic recruitment of the HDAC3 to the binding sites. Collectively, these results establish the SOX30/HDAC3 signaling as a key regulator of the transcriptional program in a deacetylase-independent manner during the meiotic-to-postmeiotic transition in spermatogenesis.

Anti-apoptosis effect of recombinant human interleukin-11 in neonatal hypoxic-ischemic rats through activating the IL-11Rα/STAT3 signaling pathway.

Hypoxia-ischemia (HI) is one of the most common causes of death and disability in neonates. Apoptosis contributes to HI development. Interleukin-11(IL-11) has been shown to protect mice from cerebral ischemia/reperfusion injury. However, whether IL-11 exerts the anti-apoptotic effect on HI injury is unclear. In this study, we demonstrated that recombinant human IL-11 (rhIL-11) prevented apoptosis of rat neonates with HI through activating IL-11Rα/STAT3 signaling. Sprague-Dawley rat pups on the 7th day after birth were used to establish an HI injury model. The expression levels of IL-11Rα and GP130 were increased first and then decreased after HI. In contrast, IL-11 expression was first decreased and then increased. Immunofluorescence staining showed that IL-11Rα was localized in neurons and oligodendrocytes. RhIL-11 treatment alleviated hippocampal and cortical damages, significantly reduced cerebral infarction volumes, cerebral edema, and loss of the Nissl body and nerve cells, and also ameliorated the outcomes of HI injury and long-term neurological deficits. In addition, rhIL-11 treatment upregulated the expressions levels of Bcl-2 and p-STAT3/STAT3, and downregulated the protein concentrations of the lytic protease, and cleaved-caspase-3. Furthermore, GP130 inhibitor and JAK1 inhibitor reversed the protective effects of rhIL-11. Overall, rhIL-11 showed an anti-apoptosis effect on the brain after HI injury. Our results indicated that rhIL-11 reduced neuronal apoptosis by activating the brain IL-11Rα/STAT3 pathway.

[Advances in the electrophysiological research on neurocognitive function in adolescents with non-suicidal self-injury]. / éžè‡ªæ€æ€§è‡ªä¼¤é’å°‘å¹´ç¥žç»è®¤çŸ¥åŠŸèƒ½ç›¸å ³ç”µç”Ÿç†ç ”ç©¶è¿›å±•.

Non-suicidal self-injury (NSSI) is becoming increasingly common in adolescents and seriously affects their physical and mental health, and it is also a major risk factor for suicide among adolescents. NSSI has now become a public health issue of general concern; however, the identification of cognitive dysfunction in NSSI is still based on neuropsychological cognitive assessment and subjective questionnaire assessment, with a lack of objective evaluation indicators. As a method for studying the cognitive neural mechanism of NSSI, electroencephalography is a reliable tool for finding objective biomarkers of NSSI. This article reviews the recent research on electrophysiology associated with cognitive dysfunction in adolescents with NSSI.

[Recent research on the association between depressive disorder and gene polymorphisms in adolescents]. / é’å°‘å¹´æŠ‘éƒéšœç¢ä¸ŽåŸºå› å¤šæ€æ€§çš„ç ”ç©¶è¿›å±•.

Biogenetics plays an important role in the pathogenesis of depressive disorder in adolescents. Various genetic polymorphism studies have updated the understanding of adolescent depressive disorder. However, due to the influence of gene-environment interaction and age of puberty, the influence of gene polymorphisms on adolescent depressive disorder is complicated to clarify. Investigating and clarifying the relationship between gene polymorphisms and adolescent depressive disorder will promote the research on the pathogenesis of this disorder and provide a reference for the prevention and treatment of this disorder. This article reviews the genetic polymorphisms related to adolescent depressive disorder.

The ssDNA-binding protein MEIOB acts as a dosage-sensitive regulator of meiotic recombination.

Meiotic recombination enables reciprocal exchange of genetic information between parental chromosomes and is essential for fertility. MEIOB, a meiosis-specific ssDNA-binding protein, regulates early meiotic recombination. Here we report that the human infertility-associated missense mutation (N64I) in MEIOB causes protein degradation and reduced crossover formation in mouse testes. Although the MEIOB N64I substitution is associated with human infertility, the point mutant mice are fertile despite meiotic defects. Meiob mutagenesis identifies serine 67 as a critical residue for MEIOB. Biochemically, these two mutations (N64I and S67 deletion) cause self-aggregation of MEIOB and sharply reduced protein half-life. Molecular genetic analyses of both point mutants reveal an important role for MEIOB in crossover formation in late meiotic recombination. Furthermore, we find that the MEIOB protein levels directly correlate with the severity of meiotic defects. Our results demonstrate that MEIOB regulates meiotic recombination in a dosage-dependent manner.

Dual functions for the ssDNA-binding protein RPA in meiotic recombination.

Meiotic recombination permits exchange of genetic material between homologous chromosomes. The replication protein A (RPA) complex, the predominant ssDNA-binding complex, is required for nearly all aspects of DNA metabolism, but its role in mammalian meiotic recombination remains unknown due to the embryonic lethality of RPA mutant mice. RPA is a heterotrimer of RPA1, RPA2, and RPA3. We find that loss of RPA1, the largest subunit, leads to disappearance of RPA2 and RPA3, resulting in the absence of the RPA complex. Using an inducible germline-specific inactivation strategy, we find that loss of RPA completely abrogates loading of RAD51/DMC1 recombinases to programmed meiotic DNA double strand breaks, thus blocking strand invasion required for chromosome pairing and synapsis. Surprisingly, loading of MEIOB, SPATA22, and ATR to DNA double strand breaks is RPA-independent and does not promote RAD51/DMC1 recruitment in the absence of RPA. Finally, inactivation of RPA reduces crossover formation. Our results demonstrate that RPA plays two distinct roles in meiotic recombination: an essential role in recombinase recruitment at early stages and an important role in promoting crossover formation at later stages.

A TCF-Based Carbon Monoxide NIR-Probe without the Interference of BSA and Its Application in Living Cells.

As toxic gaseous pollution, carbon monoxide (CO) plays an essential role in many pathological and physiological processes, well-known as the third gasotransmitter. Owning to the reducibility of CO, the Pd0-mediated Tsuji-Trost reaction has drawn much attention in CO detection in vitro and in vivo, using allyl ester and allyl ether caged fluorophores as probes and PdCl2 as co-probes. Because of its higher decaging reactivity than allyl ether in the Pd0-mediated Tsuji-Trost reaction, the allyl ester group is more popular in CO probe design. However, during the application of allyl ester caged probes, it was found that bovine serum albumin (BSA) in the fetal bovine serum (FBS), an irreplaceable nutrient in cell culture media, could hydrolyze the allyl ester bond, and thus give erroneous imaging results. In this work, dicyanomethylenedihydrofuran (TCF) and dicyanoisophorone (DCI) were selected as electron acceptors for constructing near-infrared-emission fluorophores with electron donor phenolic OH. An allyl ester and allyl ether group were installed onto TCF-OH and DCI-OH, constructing four potential CO fluorescent probes, TCF-ester, TCF-ether, DCI-ester, and DCI-ether. Our data revealed that ester bonds of TCF-ester and DCI-ester could completely hydrolyze in 20 min, but ether bonds in TCF-ether and DCI-ether tolerate the hydrolysis of BSA and no released fluorescence was observed even up to 2 h. Moreover, passing through the screen, it was concluded that TCF-ether is superior to DCI-ether due to its higher reactivity in a Pd0-mediated Tsuji-Trost reaction. Also, the large stokes shift of TCF-OH, absorption and emission at 408 nm and 618 nm respectively, make TCF-ether desirable for fluorescent imaging because of differentiating signals from the excitation light source. Lastly, TCF-ether has been successfully applied to the detection of CO in H9C2 cells.

[Short-term persistent symptoms in preschool children with mild/common coronavirus disease 2019 caused by Omicron variant infection after discharge: a follow-up study]. / Omicronå˜å¼‚æ ªæ„ŸæŸ“çš„è½»åž‹/æ™®é€šåž‹æ–°åž‹å† çŠ¶ç— æ¯’è‚ºç‚Žå­¦é¾„å‰å„¿ç«¥å‡ºé™¢åŽçŸ­æœŸç›¸å ³æŒç»­ç—‡çŠ¶çš„éšè®¿.

OBJECTIVES: To investigate the persistent symptoms in preschool children after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection, and to provide a basis for developing follow-up plans after infection and reducing and preventing related symptoms after infection. METHODS: The children, aged 0-5 years, who had Omicron BA.2 infection and were discharged from the pediatric ward of Shanghai Renji Hospital South Branch from April 13 to May 8, 2022, were enrolled as subjects, and related demographic and clinical data were collected. The children were followed up from the time to SARS-CoV-2 clearance for two consecutive tests with an interval of >24 hours till 4-5 weeks after clearance, and telephone follow-up was performed on the primary caregivers to investigate related persistent symptoms. RESULTS: Among the 103 children who met the inclusion criteria, there were 61 boys and 42 girls, with a median age of 18 months. The primary caregivers who had received two or more doses of COVID-19 vaccine accounted for 64.1% (66/103). Fever (98.1%, 101/103) was the most common symptom in these children, followed by cough/expectoration (63.1%, 65/103), gastrointestinal problems (37.9%, 39/103), loss of appetite (30.1%, 31/103), weakness (27.2%, 28/103), and nasal obstruction/runny nose (16.5%, 17/103). The follow-up at 1 month after discharge reported that 44 children (42.7%) had at least one persistent symptom, including respiratory symptoms in 14 children (13.6%) and gastrointestinal problems in 19 children (18.4%). The children whose primary caregivers received two or more doses of COVID-19 vaccine had a significantly shorter time to SARS-CoV-2 clearance than those whose primary caregivers did not receive or only received one dose of COVID-19 vaccine (P<0.05), while there was no significant difference between the two groups in the proportion of children with at least one persistent symptom (P>0.05). CONCLUSIONS: Nearly half of the preschool children may have related persistent symptoms after SARS-CoV-2 Omicron variant infection, mainly gastrointestinal and respiratory symptoms. Most of the symptoms may be mild, and continuous follow-up is needed to observe their outcomes. Vaccination of COVID-19 vaccine for primary caregivers has a certain protective effect on children.

Sox30 initiates transcription of haploid genes during late meiosis and spermiogenesis in mouse testes.

Transcription factors of the Sox protein family contain a DNA-binding HMG box and are key regulators of progenitor cell fate. Here, we report that expression of Sox30 is restricted to meiotic spermatocytes and postmeiotic haploids. Sox30 mutant males are sterile owing to spermiogenic arrest at the early round spermatid stage. Specifically, in the absence of Sox30, proacrosomic vesicles fail to form a single acrosomal organelle, and spermatids arrest at step 2-3. Although most Sox30 mutant spermatocytes progress through meiosis, accumulation of diplotene spermatocytes indicates a delayed or impaired transition from meiotic to postmeiotic stages. Transcriptome analysis of isolated stage-specific spermatogenic cells reveals that Sox30 controls a core postmeiotic gene expression program that initiates as early as the late meiotic cell stage. ChIP-seq analysis shows that Sox30 binds to specific DNA sequences in mouse testes, and its genomic occupancy correlates positively with expression of many postmeiotic genes including Tnp1, Hils1, Ccdc54 and Tsks These results define Sox30 as a crucial transcription factor that controls the transition from a late meiotic to a postmeiotic gene expression program and subsequent round spermatid development.

Antibiotics prescription for targeted therapy of pediatric invasive pneumococcal diseases in China: a multicenter retrospective study.

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae) is a major cause of bacterial meningitis, septicemia and pneumonia in children. Inappropriate choice of antibiotic can have important adverse consequences for both the individual and the community. Here, we focused on penicillin/cefotaxime non-susceptibility of S. pneumoniae and evaluated appropriateness of targeted antibiotic therapy for children with IPD (invasive pneumococcal diseases) in China. METHODS: A multicenter retrospective study was conducted in 14 hospitals from 13 provinces in China. Antibiotics prescription, clinical features and resistance patterns of IPD cases from January 2012 to December 2017 were collected. Appropriateness of targeted antibiotics therapy was assessed. RESULTS: 806 IPD cases were collected. The non-susceptibility rates of S. pneumoniae to penicillin and cefotaxime were 40.9% and 20.7% respectively in 492 non-meningitis cases, whereas those were 73.2% and 43.0% respectively in 314 meningitis cases. Carbapenems were used in 21.3% of non-meningitis cases and 42.0% of meningitis cases for targeted therapy. For 390 non-meningitis cases with isolates susceptible to cefotaxime, vancomycin and linezolid were used in 17.9% and 8.7% of cases respectively for targeted therapy. For 179 meningitis cases with isolates susceptible to cefotaxime, vancomycin and linezolid were prescribed in 55.3% and 15.6% of cases respectively. Overall, inappropriate targeted therapies were identified in 361 (44.8%) of 806 IPD cases, including 232 (28.8%) cases with inappropriate use of carbapenems, 169 (21.0%) cases with inappropriate use of vancomycin and 62 (7.7%) cases with inappropriate use of linezolid. CONCLUSIONS: Antibiotic regimens for IPD definite therapy were often excessive with extensive prescription of carbapenems, vancomycin or linezolid in China. Antimicrobial stewardship programs should be implemented to improve antimicrobial use.

Effect of COVID-19 outbreak on the treatment time of patients with acute ST-segment elevation myocardial infarction.

OBJECTIVE: To explore the effect of COVID-19 outbreak on the treatment time of patients with ST-segment elevation myocardial infarction (STEMI) in Hangzhou, China. METHODS: We retrospectively reviewed the data of STEMI patients admitted to the Hangzhou Chest Pain Center (CPC) during a COVID-19 epidemic period in 2020 (24 cases) and the same period in 2019 (29 cases). General characteristics of the patients were recorded, analyzed, and compared. Moreover, we compared the groups for the time from symptom onset to the first medical contact (SO-to-FMC), time from first medical contact to balloon expansion (FMC-to-B), time from hospital door entry to first balloon expansion (D-to-B), and catheter room activation time. The groups were also compared for postoperative cardiac color Doppler ultrasonographic left ventricular ejection fraction (LVEF),the incidence of major adverse cardiovascular and cerebrovascular events (MACCE),Kaplan-Meier survival curves during the 28 days after the operation. RESULTS: The times of SO-to-FMC, D-to-B, and catheter room activation in the 2020 group were significantly longer than those in the 2019 group (P < 0.05). The cumulative mortality after the surgery in the 2020 group was significantly higher than the 2019 group (P < 0.05). CONCLUSION: The pre-hospital and in-hospital treatment times of STEMI patients during the COVID-19 epidemic were longer than those before the epidemic. Cumulative mortality was showed in Kaplan-Meier survival curves after the surgery in the 2020 group was significantly different higher than the 2019 group during the 28 days.The diagnosis and treatment process of STEMI patients during an epidemic should be optimized to improve their prognosis.

[Overexpression of human EP4 receptor in vascular smooth muscle cells attenuates angiotensin II-induced hypertension in mice].

Prostaglandin E2 (PGE2) plays an important role in cardiovascular system. PGE2 regulates blood pressure through its 4 G protein coupled receptors, i.e., EP1, EP2, EP3, and EP4. The aim of this study was to investigate the role of EP4 receptors in vascular smooth muscle cells (VSMC) in blood pressure regulation. VSMC-specific human EP4 transgenic (VSMC-hEP4 Tg) mice were generated and genotyped. The systolic blood pressure (SBP) of the VSMC-hEP4 Tg mice and the wild-type (WT) littermates was measured under normal, low-salt (LSD) and high-salt diet (HSD) conditions using a tail-cuff method. Both WT and VSMC-hEP4 Tg mice were administered with a chronic infusion of angiotensin II (Ang II) with an osmotic pump and SBP levels were monitored every week. The mean arterial blood pressure (MAP) of WT and VSMC-hEP4 Tg mice upon Ang II intravenous infusion was measured via carotid arterial catheterization. Ang II-induced vasoconstriction of the mesenteric arterial rings from WT and VSMC-hEP4 Tg mice was measured using the multi myograph system. The effect of PGE1-OH (a selective EP4 agonist) on Ang II-induced phosphorylation of myosin phosphatase target subunit 1 (MYPT1) was detected by Western blot. The effect of two additional EP4 specific agonists (CAY10580 and CAY10598, 0.5 mg/kg) on blood pressure of WT mice was measured by carotid arterial catheterization. The results showed that the VSMC-hEP4 Tg mice were successfully generated and their basal SBP levels were lower than those of WT mice. Although blood pressure levels were significantly altered in WT mice under LSD and HSD, little change was observed in the VSMC-hEP4 Tg mice. After a chronic infusion and an acute intravenous injection of Ang II, SBP levels of VSMC-hEP4 Tg mice were significantly lower than those of WT mice. In addition, both CAY10580 and CAY10598 significantly reduced MAP levels of WT mice. Ex vivo study showed that treatment of isolated mesenteric arteries with PGE1-OH inhibited Ang II-induced phosphorylation of MYPT1. Collectively, these results demonstrate that specific overexpression of human EP4 gene in VSMCs significantly reduces basal blood pressure levels and attenuates Ang II-induced hypertension, possibly via inhibiting Ang II/AT1 signaling pathway. Our findings suggest that EP4 may represent an attractive target for the treatment of hypertension.

Glial Cell Line-Derived Neurotrophic Factor Enhances Autophagic Flux in Mouse and Rat Hepatocytes and Protects Against Palmitate Lipotoxicity.

Glial cell line-derived neurotrophic factor (GDNF) is a protein that is required for the development and survival of enteric, sympathetic, and catecholaminergic neurons. We previously reported that GDNF is protective against high fat diet (HFD)-induced hepatic steatosis in mice through suppression of hepatic expression of peroxisome proliferator activated receptor-γ and genes encoding enzymes involved in de novo lipogenesis. We also reported that transgenic overexpression of GDNF in mice prevented the HFD-induced liver accumulation of the autophagy cargo-associated protein p62/sequestosome 1 characteristic of impaired autophagy. Here we investigated the effects of GDNF on hepatic autophagy in response to increased fat load, and on hepatocyte mitochondrial fatty acid ß-oxidation and cell survival. GDNF not only prevented the reductions in the liver levels of some key autophagy-related proteins, including Atg5, Atg7, Beclin-1 and LC3A/B-II, seen in HFD-fed control mice, but enhanced their levels after 12 weeks of HFD feeding. In vitro, GDNF accelerated autophagic cargo clearance in primary mouse hepatocytes and a rat hepatocyte cell line, and reduced the phosphorylation of the mechanistic target of rapamycin complex downstream-target p70S6 kinase similar to the autophagy activator rapamycin. GDNF also enhanced mitochondrial fatty acid ß-oxidation in primary mouse and rat hepatocytes, and protected against palmitate-induced lipotoxicity. Conclusion: We demonstrate a role for GDNF in enhancing hepatic autophagy and in potentiating mitochondrial function and fatty acid oxidation. Our studies show that GDNF and its receptor agonists could be useful for enhancing hepatocyte survival and protecting against fatty acid-induced hepatic lipotoxicity.

Effects of ticagrelor pretreatment on electrophysiological properties of stellate ganglion neurons following myocardial infarction.

Higher sympathetic activity predisposes to malignant ventricular arrhythmias in the context of myocardial infarction (MI). This is, in part, mediated by the electrical activity of the stellate ganglion (SG). The aim of this study is to examine the effects of ticagrelor pretreatment on the electrophysiological properties of SG neurons following MI in rabbits. MI was induced by isoproterenol (ISO) of 150 mg kg-1 d-1 (twice at an interval of 24 hours). Ticagrelor pretreatment was administered at low- (10 mg kg-1 d-1) or high-dose (20 mg kg-1 d-1). Protein and RNA expression were determined by immunohistochemical analysis and real-time PCR, respectively. The activity of sodium channel current (INa), delayed rectifier potassium current (IKDR), M-type potassium current (IKM) as well as action potentials (APs) from SG neurons were measured by whole-cell patch-clamp. Intracellular calcium concentrations were measured by confocal microscopy. Compared with the control group, the MI group exhibited a greater amplitude of INa, IKDR and IKM, significantly altered activation and inactivation characteristics of INa, no significant alterations in protein or mRNA expression of sodium and M-type potassium channels, along with higher AP amplitude and frequency and intracellular calcium concentrations. Most of these abnormalities were prevented by pretreatment with low- or high-dose ticagrelor. Our data suggest that ticagrelor exerts cardioprotective effects, potentially through modulating the activity of different ion channels in SG neurons.

Biological and RNA regulatory function of MOV10 in mammalian germ cells.

BACKGROUND: RNA regulation by RNA-binding proteins (RBPs) involve extremely complicated mechanisms. MOV10 and MOV10L1 are two homologous RNA helicases implicated in distinct intracellular pathways. MOV10L1 participates specifically in Piwi-interacting RNA (piRNA) biogenesis and protects mouse male fertility. In contrast, the functional complexity of MOV10 remains incompletely understood, and its role in the mammalian germline is unknown. Here, we report a study of the biological and molecular functions of the RNA helicase MOV10 in mammalian male germ cells. RESULTS: MOV10 is a nucleocytoplasmic protein mainly expressed in spermatogonia. Knockdown and transplantation experiments show that MOV10 deficiency has a negative effect on spermatogonial progenitor cells (SPCs), limiting proliferation and in vivo repopulation capacity. This effect is concurrent with a global disturbance of RNA homeostasis and downregulation of factors critical for SPC proliferation and/or self-renewal. Unexpectedly, microRNA (miRNA) biogenesis is impaired due partially to decrease of miRNA primary transcript levels and/or retention of miRNA via splicing control. Genome-wide analysis of RNA targetome reveals that MOV10 binds preferentially to mRNAs with long 3'-UTR and also interacts with various non-coding RNA species including those in the nucleus. Intriguingly, nuclear MOV10 associates with an array of splicing factors, particularly with SRSF1, and its intronic binding sites tend to reside in proximity to splice sites. CONCLUSIONS: These data expand the landscape of MOV10 function and highlight a previously unidentified role initiated from the nucleus, suggesting that MOV10 is a versatile RBP involved in a broader RNA regulatory network.