Expression of long non-coding RNAs in complete transection spinal cord injury: a transcriptomic analysis

Long non-coding RNAs(lncRNAs)are abundantly expressed in the central nervous system and exert a critical role in gene regulation via multiple biological processes.To uncover the functional significance and molecular mechanisms of lncRNAs in spinal cord injury(SCI),the expression signatures of lncRNAs were profiled using RNA sequencing(RNA-seq)technology in a Sprague-Dawley rat model of the 10th thoracic vertebra complete transection SCI.Results showed that 116 of 14,802 detected lncRNAs were differentially expressed,among which 16—including eight up-regulated(H19,Vof16,Hmox2-ps1,LOC100910973,Ybx1-ps3,Nnat,Gcgr,LOC680254)and eight down-regulated(Rmrp,Terc,Ngrn,Ppp2r2b,Cox6a2,Rpl37a-ps1,LOC360231,Rpph1)—demonstrated fold changes>2 in response to transection SCI.A subset of these RNA-seq results was validated by quantitative real-time PCR.The levels of 821 mRNAs were also significantly altered post-SCI;592 mRNAs were up-regulated and 229 mRNAs were down-regulated by more than 2-fold.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analyses showed that differentially expressed mRNAs were related to GO biological processes and molecular functions such as injury and inflammation response,wound repair,and apoptosis,and were significantly enriched in 15 KEGG pathways,including cell phagocytosis,tumor necrosis factor alpha pathway,and leukocyte migration.Our results reveal the expression profiles of lncRNAs and mRNAs in the rat spinal cord of a complete transection model,and these differentially expressed lncRNAs and mRNAs represent potential novel targets for SCI treatment.We suggest that lncRNAs may play an important role in the early immuno-inflammatory response after spinal cord injury.This study was approved by the Administration Committee of Experimental Animals,Guangdong Province,China.

Effect of lentiviral vector-mediated overexpression of hypoxia-inducible factor 1 alpha delivered by pluronic F-127 hydrogel on brachial plexus avulsion in rats

Brachial plexus avulsion often results in massive motor neuron death and severe functional deficits of target muscles. However, no satisfactory treatment is currently available. Hypoxia-inducible factor 1α is a critical molecule targeting several genes associated with ischemia-hypoxia damage and angiogenesis. In this study, a rat model of brachial plexus avulsion-reimplantation was established, in which C5–7 ventral nerve roots were avulsed and only the C6 root reimplanted. Different implants were immediately injected using a microsyringe into the avulsion-reimplantation site of the C6 root post-brachial plexus avulsion. Rats were randomly divided into five groups: phosphate-buffered saline, negative control of lentivirus, hypoxia-inducible factor 1α(hypoxia-inducible factor 1α overexpression lentivirus), gel(pluronic F-127 hydrogel), and gel + hypoxia-inducible factor 1α(pluronic F-127 hydrogel + hypoxia-inducible factor 1α overexpression lentivirus). The Terzis grooming test was performed to assess recovery of motor function. Scores were higher in the hypoxia-inducible factor 1α and gel +hypoxia-inducible factor 1α groups(in particular the gel + hypoxia-inducible factor 1α group) compared with the phosphate-buffered saline group. Electrophysiology, fluorogold retrograde tracing, and immunofluorescent staining were further performed to investigate neural pathway reconstruction and changes of neurons, motor endplates, and angiogenesis. Compared with the phosphate-buffered saline group, action potential latency of musculocutaneous nerves was markedly shortened in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor1α groups. Meanwhile, the number of fluorogold-positive cells and ChAT-positive neurons, neovascular area(labeled by CD31 around av ulsed sites in ipsilateral spinal cord segments), and the number of motor endplates in biceps brachii(identified by α-bungarotoxin) were all visibly increased, as well as the morphology of motor endplate in biceps brachil was clear in the hypoxia-inducible factor 1α and gel + hypoxia-inducible factor 1α groups. Taken together, delivery of hypoxia-inducible factor 1α overexpression lentiviral vectors mediated by pluronic F-127 effectively promotes spinal root regeneration and functional recovery post-brachial plexus avulsion. All animal procedures were approved by the Institutional Animal Care and Use Committee of Guangdong Medical University, China.

Retroperitoneal teratoma resection assisted by 3-dimensional visualization and virtual reality:A case report

BACKGROUND Primary retroperitoneal tumor is a rare type of tumor with insidious onset,large tumor size at the time of diagnosis,and often extensive involvement of surrounding tissues and blood vessels in the retroperitoneum.Surgery for primary retroperitoneal tumors is technically challenging.Preoperative imaging evaluation is critical for the selection of the optimal surgical approach and can influence complete resection and recurrence rates.Three-dimensional model reconstruction combined with virtual reality is useful for preoperative assessment.CASE SUMMARY A 17-year-old female patient was admitted for abdominal pain lasting for half a year that had been worsening for half a month.Abdominopelvic enhanced helical computed tomography revealed a retroperitoneal space-occupying lesion about 11.3 cm×9.1 cm in size,with well-defined borders in the upper left quadrant of the abdomen.The lesion compressed the left renal artery and vein resulting in vascular displacement and deformation.A multidisciplinary team decided on the optimal treatment approach.Preoperative three-dimensional visualization and virtual reality technology were used to assess and simulate the surgical procedure.Then,retroperitoneal tumor resection along with renal artery reconstruction was decided as the treatment.Complete resection of the retroperitoneal tumor was performed.Stable blood flow was established after renal artery reconstruction.The tumor was diagnosed as mature cystic teratoma(retroperitoneal tumor)by postoperative pathologic analysis.The patient,who recovered well,was discharged after 2 wk and maintains regular follow-ups.CONCLUSION A combination of three-dimensional reconstruction and virtual reality technology before surgery improves the rate of complete resection of retroperitoneal teratoma.

Single-cell Immune Landscape of Human Recurrent Miscarriage

t Successful pregnancy in placental mammals substantially depends on the establishment of maternal immune tolerance to the semi-allogenic fetus.Disorders in this process are tightly associated with adverse pregnancy outcomes including recurrent miscarriage(RM).However,an indepth understanding of the systematic and decidual immune environment in RM remains largely lacking.In this study,we utilized single-cell RNA-sequencing(scRNA-seq)to comparably analyze the cellular and molecular signatures of decidual and peripheral leukocytes in normal and unexplained RM pregnancies at the early stage of gestation.Integrative analysis identifies 22 distinct cell clusters in total,and a dramatic difference in leukocyte subsets and molecular properties in RM cases is revealed.Specifically,the cytotoxic properties of CD8^(+)effector T cells,nature killer(NK),and mucosal-associated invariant T(MAIT)cells in peripheral blood indicates apparently enhanced pro-inflammatory status,and the population proportions and ligand–receptor interactions of the decidual leukocyte subsets demonstrate preferential immune activation in RM patients.The molecular features,spatial distribution,and the developmental trajectories of five decidual NK(dNK)subsets have been elaborately illustrated.In RM patients,a dNK subset that supports embryonic growth is diminished in proportion,while the ratio of another dNK subset with cyto toxic and immune-active signature is significantly increased.Notably,a unique pro-inflammatory CD56^(+)CD16^(+)dNK subset substantially accumulates in RM decidua.These findings reveal a comprehensive cellular and molecular atlas of decidual and peripheral leukocytes in human early pregnancy and provide an in-depth insight into the immune pathogenesis for early pregnancy loss.

3D chromatin architecture and epigenetic regulation in cancer stem cells

Dedifferentiation of cell identity to a progenitor-like or stem cell-like state with increased cellular plasticity is frequently observed in cancer formation.During this process,a subpopulation of cells in tumours acquires a stem cell-like state partially resembling to naturally occurring pluripotent stem cells that are temporarily present during early embryogenesis.Such characteristics allow these cancer stem cells(CSCs)to give rise to the whole tumour with its entire cellular heterogeneity and thereby support metastases formation while being resistant to current cancer therapeutics.Cancer development and progression are demarcated by transcriptional dysregulation.In this article,we explore the epigenetic mechanisms shaping gene expression during tumorigenesis and cancer stem cell formation,with an emphasis on 3D chromatin architecture.Comparing the pluripotent stem cell state and epigenetic reprogramming to dedifferentiation in cellular transformation provides intriguing insight to chromatin dynamics.We suggest that the 3D chromatin architecture could be used as a target for re-sensitizing cancer stem cells to therapeutics.

Cell Stem Cell：利用干细胞制造出的心肌细胞有助精准心血管医疗取得进展

在一项新的研究中。来自美国斯坦福大学医学院的研究人员发现利用人诱导性多能干细胞（iPS细胞）制造的心肌细胞忠实地反映供者天然的心脏组织中关键基因的表达模式。因此，这些细胞能够被用来预测病人是否可能经历药物相关的心脏损伤。相关研究结果在线发表在Cell Stem Cell期刊上。论文标题为＂Transcriptome Profiling of Patient -Specific Human iPSC - ardiomyocytes Predicts Individual Drug Safety and Efficacy Responses In Vitro＂.

Return to the hematopoietic stem cell origin

Studying embryonic hematopoiesis is complicated by diversity of its locations in the constantly changing anatomy and by the mobility of blood cell precursors.Embryonic hematopoietic progenitors are identified in traditional in vivo and in vitro cell potential assays.Profound epigenetic plasticity of mammalian embryonic cells combined with significant inductive capacity of the potential assays suggest that our understanding of hematopoietic ontogenesis is substantially distorted.Non-invasive in vivo cell tracing methodology offers a better insight into complex processes of blood cell specification.In contrast to the widely accepted view based on the cell potential assays,the genetic tracing approach identified the yolk sac as the source of adult hematopoietic stem cell lineage.Realistic knowledge of the blood origin is critical for safe and efficient recapitulation of hematopoietic development in culture.

RNA binding protein 24 deletion disrupts global alternative splicing and causes dilated cardiomyopathy

RNA splicing contributes to a broad spectrum of posttranscriptional gene regulation during normal development, as well as pathological manifestation of heart diseases. However, the functional role and regulation of splicing in heart failure remain poorly understood. RNA binding protein (RBP), a major component of the splicing machinery, is a critical factor in this process. RNA binding motif protein 24 (RBM24) is a tissue-specific RBP which is highly expressed in human and mouse heart. Previous studies demonstrated the functional role of RBM24 in the embryonic heart development. However, the role of RBM24 in postnatal heart development and heart disease has not been investigated. In this paper, using conditional RBM24 knockout mice, we demonstrated that ablation of RBM24 in postnatal heart led to rapidly progressive dilated cardiomyopathy (DCM), heart failure, and postnatal lethality. Global splicing profiling revealed that RBM24 regulated a network of genes related to cardiac function and diseases. Knockout of RBM24 resulted in misregulation of these splicing transitions which contributed to the subsequent development of cardiomyopathy. Notably, our analysis identified RBM24 as a splice factor that determined the splicing switch of a subset of genes in the sacomeric Z-disc complex, including Titin, the major disease gene of DCM and heart failure. Together, this study identifies regulation of RNA splicing by RBM24 as a potent player in remodeling of heart during postnatal development, and provides novel mechanistic insights to the pathogenesis of DCM.

Ethacrynic acid targets GSTM1 to ameliorate obesity by promoting browning of white adipocytes

Dear Editor,Obesity is caused by an imbalance between energy intake and expenditure,and has become a global epidemic with over 650 million adults affected.Adipose tissues in mammals are composed of white adipose tissue(WAT)and classical brown adipose tissue(BAT),and their balance is highly related to the occurrence of obesity.The browning of white adipocytes results in“beige”or“brite”adipocytes,which appear functionally similar to classical brown adipocytes,and can be detected in WAT deposits of animals that have been exposed to cold or other inducers(Fu et al.,2015).

Effective gene targeting in rabbits using RNA-guided Cas9 nucleases

Dear Editor, Recently, zinc finger nuclease, transcrip- tion activator-like effector nuclease, and RNA-guided Cas9 endonuciease （Cas9） have emerged as powerful means for genome editing （Conklin, 2013; Gaj eta[., 2013）. These nucleases are efficient in gen- erating double-strand breaks in the genome that can be repaired by error-prone nonho- mologous end joining leading to a functional knockout （KO） of the targeted gene or used to integrate a DNA sequence at a specific locus through homologous recombination.