Objective:Herbal medicine is an important therapeutic option for benign prostatic hyperplasia(BPH),a common disease in older men that can seriously affect their quality of life.Currently,it is crucial to develop agent...Objective:Herbal medicine is an important therapeutic option for benign prostatic hyperplasia(BPH),a common disease in older men that can seriously affect their quality of life.Currently,it is crucial to develop agents with strong efficacy and few side effects.Herein we investigated the effects of the extract of Rauwolfia vomitoria,a shrub grown in West Africa,on BPH.Methods:Rats with testosterone-induced BPH were treated with R.vomitoria.Prostates were histologically analyzed by Hematoxylin and eosin staining.Proliferation index and the expression levels of androgen receptor and its associated proteins were quantified through immunohistochemistry and immunoblotting.Androgen receptor target genes were examined by quantitative real-time polymerase chain reaction.The sperm count and body weight of rats were also measured.Results:The oral administration of R.vomitoria extract significantly reduced the prostate weight and prostate weight index in BPH rats,supported by the decreased thickness of the prostate epithelial layer and increased lumen size.Similar effects were observed in the BPH rats treated with the reference drug,finasteride.R.vomitoria extract significantly reduced the testosterone-induced proliferation markers,including proliferating cell nuclear antigen and cyclin D1,in the prostate glands of BPH rats;it also reduced levels of androgen receptor,its associated protein steroid 5 a-reductase 1 and its downstream target genes(FK506-binding protein 5 and matrix metalloproteinase 2).Notably,compared with the finasteride group,R.vomitoria extract did not significantly reduce sperm count.Conclusion:R.vomitoria suppresses testosterone-induced BPH development.Due to its milder side effects,R.vomitoria could be a promising therapeutic agent for BPH.展开更多
Hearing relies on the structural and functional integrity of cochlear hair cells,particularly their apical F-actin-filled stereocilia.Phospholipid scramblases are important for maintaining membrane asymmetry,but their...Hearing relies on the structural and functional integrity of cochlear hair cells,particularly their apical F-actin-filled stereocilia.Phospholipid scramblases are important for maintaining membrane asymmetry,but their roles in the stereocilia and auditory functions are not fully understood.Here,we identify Plscr5 as a downstream target of the transcription factor POU4F3 essential for hair cell function,whose mutation causes human DFNA15 deafness.Plscr5 knockout mice exhibit progressive hearing loss due to stereocilia degeneration and hair cell loss.Functional analyses reveal that PLSCR5 contributes to phosphatidylserine externalization in hair cell apical membranes,particularly in inner hair cells,and is important for outer hair cell and stereocilia maintenance.Our findings highlight PLSCR5 as an important downstream effector of POU4F3 and regulator of phosphatidylserine externalization and membrane dynamics required for auditory functions.展开更多
The persistence of covalently closed circular DNA(cccDNA)in hepatitis B virus(HBV)-infected hepatocytes remains a major obstacle to effective antiviral treatment.Understanding the molecular mechanisms regulating HBV c...The persistence of covalently closed circular DNA(cccDNA)in hepatitis B virus(HBV)-infected hepatocytes remains a major obstacle to effective antiviral treatment.Understanding the molecular mechanisms regulating HBV cccDNA transcription is essential for developing novel therapeutic strategies.In this study,we investigated the role of RNA binding motif protein 25(RBM25)in HBV replication,focusing on its interaction with cccDNA and its regulation of host transcription factors.The results demonstrated that RBM25 knockdown markedly inhibited HBV replication,reducing levels of HBV DNA,hepatitis B e antigen(HBeAg),hepatitis B surface antigen(HBsAg),HBV RNA,and L-HBs in HBV-replicating and infected cell models.Consistent results were observed in a mouse model hydrodynamically injected with 1.2HBV plasmid.Conversely,RBM25 overexpression significantly enhanced HBV replication.Mechanistically,RBM25 promoted HBV promoter activities by binding to cccDNA through its RE/RD and PWI domains.This effect was mediated by increased Yin Yang 1(YY1)expression,which enhanced acetylation of cccDNA-bound histones,promoting HBV transcription.Furthermore,RBM25 expression was upregulated and translocated to the nucleus following core protein expression and accumulation,while overexpression of RBM25 promoted core protein degradation.In conclusion,this study demonstrates that RBM25 is a novel host factor that enhances HBV replication by upregulating YY1-dependent transcriptional activation of cccDNA.It also reveales a reciprocal regulatory mechanism between the HBV core protein and RBM25,which helps sustain HBV replication.展开更多
Accurate timing of myelination is crucial for the proper functioning of the central nervous system. Here, we identified a de novo heterozygous mutation in TMEM63A (c.1894G>A;p. Ala632Thr) in a 7-year-old boy exhibi...Accurate timing of myelination is crucial for the proper functioning of the central nervous system. Here, we identified a de novo heterozygous mutation in TMEM63A (c.1894G>A;p. Ala632Thr) in a 7-year-old boy exhibiting hypomyelination. A Ca2+ influx assay suggested that this is a loss-of-function mutation. To explore how TMEM63A deficiency causes hypomyelination, we generated Tmem63a knockout mice. Genetic deletion of TMEM63A resulted in hypomyelination at postnatal day 14 (P14) arising from impaired differentiation of oligodendrocyte precursor cells (OPCs). Notably, the myelin dysplasia was transient, returning to normal levels by P28. Primary cultures of Tmem63a^(−/−) OPCs presented delayed differentiation. Lentivirus-based expression of TMEM63A but not TMEM63A_A632T rescued the differentiation of Tmem63a^(−/−) OPCs in vitro and myelination in Tmem63a^(−/−) mice. These data thus support the conclusion that the mutation in TMEM63A is the pathogenesis of the hypomyelination in the patient. Our study further demonstrated that TMEM63A-mediated Ca^(2+) influx plays critical roles in the early development of myelin and oligodendrocyte differentiation.展开更多
Looking back a decade ago when I decided to use ＂model animal＂ to name our newly established institute, my outrageous boldness can only be described by the old Chinese slang, ＂newborn calf could never sense the dan...Looking back a decade ago when I decided to use ＂model animal＂ to name our newly established institute, my outrageous boldness can only be described by the old Chinese slang, ＂newborn calf could never sense the danger of tiger＂. Happily, my courageous belief, along with the hard work of my colleagues at Model Animal Research Center of Nanjing University, paid off eventually. We have witnessed the great progress in this research field in China in the past 10 years. This issue of Science China Life Sciences samplings some of these accomplishments.展开更多
Several factors have been implicated in obesity-related hypertension, but the genesis of the hypertension is largely unknown. In this study, we found a significantly upregulated expression of CPI-17(C-kinasepotentiate...Several factors have been implicated in obesity-related hypertension, but the genesis of the hypertension is largely unknown. In this study, we found a significantly upregulated expression of CPI-17(C-kinasepotentiated protein phosphatase 1 inhibitor of 17 kDa) and protein kinase C(PKC) isoforms in the vascular smooth muscles of high-fat diet(HFD)-fed obese mice. The obese wild-type mice showed a significant elevation of blood pressure and enhanced calcium-sensitized contraction of vascular smooth muscles. However, the obese CPI-17-deficient mice showed a normotensive blood pressure, and the calcium-sensitized contraction was consistently reduced. In addition, the mutant muscle displayed an abolished responsive force to a PKC activator and a 30%-50% reduction in both the initial peak force and sustained force in response to various G protein-coupled receptor(GPCR) agonists. Our observations showed that CPI-17-mediated calcium sensitization is mediated through a GPCR/PKC/CPI-17/MLCP/RLC signaling pathway. We therefore propose that the upregulation of CPI-17-mediated calcium-sensitized vasocontraction by obesity contributes to the development of obesity-related hypertension.展开更多
Recovery from injury to the peripheral nervous system is different from that of the central nervous system in that it can lead to gene reprogramming that can induce the expression of a series of regeneration-associate...Recovery from injury to the peripheral nervous system is different from that of the central nervous system in that it can lead to gene reprogramming that can induce the expression of a series of regeneration-associated genes.This eventually leads to axonal regeneration of injured neurons.Although some regeneration-related genes have been identified,the regulatory network underlying axon regeneration remains largely unknown.To explore the regulator of axon regeneration,we performed RNA sequencing of lumbar L4 and L5 dorsal root ganglion(DRG)neurons at different time points(0,3,6,12 hours,1,3 and 7 days)after rat sciatic nerve crush.The isolation of neurons was carried out by laser capture microscopy combined with NeuN immunofluorescence staining.We found 1228 differentially expressed genes in the injured sciatic nerve tissue.The hub genes within these differentially expressed genes include Atf3,Jun,Myc,Ngf,Fgf2,Ezh2,Gfap and Il6.We verified that the expression of the enhancer of zeste homologue 2 gene(Ezh2)was up-regulated in DRG neurons after injury,and this up-regulation differed between large-and small-sized dorsal root ganglion neurons.To investigate whether the up-regulation of Ezh2 impacts axonal regeneration,we silenced Ezh2 with siRNA in cultured DRG neurons and found that the growth of the newborn axons was repressed.In our investigation into the regulatory network of Ezh2 by interpretive phenomenal analysis,we found some regulators of Ezh2(including Erk,Il6 and Hif1a)and targets(including Atf3,Cdkn1a and Smad1).Our findings suggest that Ezh2,as a nerve regeneration-related gene,participates in the repair of the injured DRG neurons,and knocking down the Ezh2 in vitro inhibits the axonal growth of DRG neurons.All the experimental procedures approved by the Administration Committee of Experimental Animals of Jiangsu Province of China(approval No.S20191201-201)on March 21,2019.展开更多
As a critical guanine nucleotide exchange factor(GEF) regulating neurite outgrowth, Trio coordinates multiple processes of cytoskeletal dynamics through activating Rac1, Cdc42 and RhoA small GTPases by two GEF domains...As a critical guanine nucleotide exchange factor(GEF) regulating neurite outgrowth, Trio coordinates multiple processes of cytoskeletal dynamics through activating Rac1, Cdc42 and RhoA small GTPases by two GEF domains, but the in vivo roles of these GEF domains and corresponding downstream effectors have not been determined yet. We established multiple lines of knockout mice and assessed the respective roles of Trio GEF domains and Rac1 in axon outgrowth. Knockout of total Trio in cerebellar granule neurons(CGNs) led to an impaired F-actin rearrangement of growth cone and hence a retarded neurite outgrowth. Such a retardation was reproduced by inhibition of GEF1 domain or knockdown of Cdc42 and restored apparently by introduction of active Cdc42. As Rac1 deficiency did not affect the neurite outgrowth of CGNs, we suggested that Trio GEF1-mediated Cdc42 activation was required for neurite outgrowth. We established a GEF2-knockout line with deletion of all Trio isoforms except a cerebella-specific Trio8, a short isoform of Trio without GEF2 domain, and used this line as a GEF2-deficient animal model. The GEF2-deficient CGNs had a normal neurite outgrowth but abolished Netrin-1-promoted growth, without affecting Netrin-1 induced Rac1 activation. We thus suggested that Trio GEF1-mediated Cdc42 activation rather than Rac1 activation drives the F-actin dynamics necessary for neurite outgrowth, while GEF2 functions in Netrin-1-promoted neurite elongation. Our results delineated the distinct roles of Trio GEF domains in neurite outgrowth, which is instructive to understand the pathogenesis of clinical Trio-related neurodevelopmental disorders.展开更多
T cells are derived from progenitor thymocytes, of which only a minority receive the appropriate TCR signal, undergo positive selection and mature. Owing to the very short lifespan of thymocytes, the prerequisite for ...T cells are derived from progenitor thymocytes, of which only a minority receive the appropriate TCR signal, undergo positive selection and mature. Owing to the very short lifespan of thymocytes, the prerequisite for posi- tive selection is survival. TCR signal-induced Bcl-2 expression is believed to play a dominant role in the survival of positively selecting thymocytes, but how Bcl-2 is directly regulated is unknown. Here we report that the immediate early gene （IEG） c-Fos can stimulate the expression of Bcl-2, depending on a specific AP-l-binding site in the Bcl-2 promoter. In c-Fos transgenic （Fos-Tg） mice, c-Fos binds to this site and promotes the expression of Bcl-2. As a result, Fos-Tg thymocytes exhibited enhanced survival, and more mature single-positive （SP） thymocytes were generated, even on a unique TCR background. The TCR repertoire remained normal in Fos-Tg mice. Our results identified c-Fos as the mediator of the stimulatory effect of TCR signaling on Bcl-2 expression. Therefore, c-Fos, as an IEG, because of its early response ability, can quickly rescue the survival of short-lived thymocytes during positive selection. Our results provide novel insight into the mechanism regulating the survival of positively selecting thymocytes.展开更多
The key regulators and regeneration-associated genes involved in axonal regeneration of neurons after injury have not been clarified.In high-throughput sequencing,various factors influence the final sequencing results...The key regulators and regeneration-associated genes involved in axonal regeneration of neurons after injury have not been clarified.In high-throughput sequencing,various factors influence the final sequencing results,including the number and size of cells,the depth of sequencing,and the method of cell separation.There is still a lack of research on the detailed molecular expression profile during the regeneration of dorsal root ganglion neuron axon.In this study,we performed lase r-capture microdissection coupled with RNA sequencing on dorsal root ganglion neurons at 0,3,6,and 12 hours and 1,3,and 7 days after sciatic nerve crush in rats.We identified three stages after dorsal root ganglion injury:early(3-12 hours),pre-regeneration(1 day),and regeneration(3-7 days).Gene expression patterns and related function enrichment res ults showed that one module of genes was highly related to axonal regeneration.We verified the up-regulation of activating transcription factor 3(Atf3),Kruppel like factor 6(Klf6),AT-rich inte raction domain 5A(Arid5α),CAMP responsive element modulator(Crem),and FOS like 1,AP-1 transcription factor Subunit(Fosl1) in dorsal root ganglion neurons after injury.Suppressing these transcription factors(Crem,Arid5o,Fosl1 and Klf6) reduced axonal regrowth in vitro.As the hub transcription factor,Atf3 showed higher expression and activity at the preregeneration and regeneration stages.G protein-coupled estrogen receptor 1(Gper1),inte rleukin 12a(Il12α),estrogen receptor 1(ESR1),and interleukin 6(IL6) may be upstream factors that trigger the activation of Atf3 during the repair of axon injury in the early stage.Our study presents the detailed molecular expression profile during axonal regeneration of dorsal root ganglion neurons after peripheral nerve injury.These findings may provide reference for the clinical screening of molecular targets for the treatment of peripheral nerve injury.展开更多
N-ethyl-N-nitrosourea （ENU） mutagenesis has led to the elucidation of several regulator genes for melanocyte and skin development. Here we characterized a mutant from ENU mutagenesis with similar phenotype as that o...N-ethyl-N-nitrosourea （ENU） mutagenesis has led to the elucidation of several regulator genes for melanocyte and skin development. Here we characterized a mutant from ENU mutagenesis with similar phenotype as that of Splotch mutant, including exencephaly, spina bifida and abnormal limbs in homozygotes as well as white belly spotting and occasionally loop-tail in heterozygotes. This novel mutant was named as SpxG. Through genome-wide linkage analysis in backcross progenies with microsatellite markers, the SpxG was confined to a region between DIMIT415 and DIMIT7 on chromosome 1, where notable Pax3 gene was located. Direct sequencing revealed that SpxG carried a nucleotide A894G missense transition in exon 6 of Pax3 gene that resulted in Asn to Asp substitution at amino acid 269 within the highly-conserved homeodomain （HD） DNA recognition module, which was the first point mutation found in this domain in mice. This N269D mutation impaired the transactivation capacity of Pax3 protein, but exerted no effect on Pax3 protein translation. The characterization of the new mutation expanded our understanding the transactivation and DNA-binding structure of Pax3 protein.展开更多
Neurotrophic factors,particularly nerve growth factor,enhance neuronal regeneration.However,the in vivo applications of nerve growth factor are largely limited by its intrinsic disadvantages,such as its short biologic...Neurotrophic factors,particularly nerve growth factor,enhance neuronal regeneration.However,the in vivo applications of nerve growth factor are largely limited by its intrinsic disadvantages,such as its short biological half-life,its contribution to pain response,and its inability to cross the blood-brain barrier.Considering that let-7(human miRNA)targets and regulates nerve growth factor,and that let-7 is a core regulator in peripheral nerve regeneration,we evaluated the possibilities of let-7 application in nerve repair.In this study,anti-let-7a was identified as the most suitable let-7 family molecule by analyses of endogenous expression and regulatory relationship,and functional screening.Let-7a antagomir demonstrated biosafety based on the results of in vivo safety assessments and it entered into the main cell types of the sciatic nerve,including Schwann cells,fibroblasts and macrophages.Use of hydrogel effectively achieved controlled,localized,and sustained delivery of let-7a antagomir.Finally,let-7a antagomir was integrated into chitosan conduit to construct a chitosan-hydrogel scaffold tissue-engineered nerve graft,which promoted nerve regeneration and functional recovery in a rat model of sciatic nerve transection.Our study provides an experimental basis for potential in vivo application of let-7a.展开更多
Myosin light chain kinases （MLCK） phosphorylate the regulatory light chain of myosin II in thick filaments and bind to F-actin-containing thin filaments with high affinity. The ability of short myosin light chain ki...Myosin light chain kinases （MLCK） phosphorylate the regulatory light chain of myosin II in thick filaments and bind to F-actin-containing thin filaments with high affinity. The ability of short myosin light chain kinase （S-MLCK） to bind F-actin is structurally attributed to the DFRXXL regions in its N-terminus. The long myosin light chain kinase （L-MLCK） has two additional DFRXXL motifs and six Ig-like modules in its N-terminal extension. The six Ig-like modules are capable of binding to stress fibers independently. Our results from the imaging analysis demonstrated that the first two intact Ig-like modules （2Ig） in N-terminal extension of L-MLCK is the minimal binding module required for microfilament binding. Binding assay confirmed that F-actin was able to bind 2Ig. Stoichiometries of 2Ig peptide were similar for myofilament or pure F-actin. The binding affinities were slightly lower than 5DFRXXL peptide as reported previously. Similar to DFRXXL peptides, the 2Ig peptide also caused efficient F-actin bundle formation in vitro. In the living cell, over-expression of 2Ig fragment increased ＂spike＂-like protrusion formation with over-bundled F-actin. Our results suggest that L-MLCK may act as a potent F-actin bundling protein via its DFRXXL region and the 2Ig region, implying that L-MLCK plays a role in cytoskeleton organization.展开更多
Dear Editor,The peripheral nervous system(PNS)regenerates more easily after injury than the central nervous system(CNS)[1].Sensory neurons in the L4–L6 dorsal root ganglia(DRGs)extend axons to form the sciatic nerve ...Dear Editor,The peripheral nervous system(PNS)regenerates more easily after injury than the central nervous system(CNS)[1].Sensory neurons in the L4–L6 dorsal root ganglia(DRGs)extend axons to form the sciatic nerve along with motor axons.The DRG neuron is one of the exceptional mature neurons whose axons can regenerate after injury.展开更多
Long noncoding RNAs(lncRNAs)are expressed in different species and different tissues,and perform different functions,but little is known about their involvement in the synthesis or secretion of follicle-stimulating ho...Long noncoding RNAs(lncRNAs)are expressed in different species and different tissues,and perform different functions,but little is known about their involvement in the synthesis or secretion of follicle-stimulating hormone(FSH).In general,we have revealed lnc RNA-micro RNA(mi RNA)-messenger RNA(m RNA)interactions that may play important roles in rat primary pituitary cells.In this study,a new lncRNA was identified for the first time.First,we analyzed the gene expression of lncRNA-m18as1 in different tissues and different stages by reverse transcription-quantitative polymerase chain reaction(RT-qPCR)and observed the localization of lncRNA-m18as1 with fluorescence in situ hybridization,which indicated that this lncRNA was distributed mainly in the cytoplasm.Next,we used RT-qPCR and enzyme-linked immunosorbent assay(ELISA)to analyze the regulation of FSH synthesis and secretion after overexpression or knockdown of lncRNA-m18as1 and found that lncRNA-m18as1 was positively correlated with FSH synthesis and secretion.In addition,mothers against decapentaplegic homolog 2(Smad2)was highly expressed in our sequencing results.We also screened miR-18a-5p from our sequencing results as a miRNA that may bind to lncRNA-m18as1 and Smad2.We used RNA immunoprecipitation-qPCR(RIP-qPCR)and/or dual luciferase assays to confirm that lncRNA-m18as1 interacted with miR-18a-5p and miR-18a-5p interacted with Smad2.Fluorescence in situ hybridization(FISH)showed that lncRNA-m18as1 and miR-18a-5p were localized mainly in the cytoplasm.Finally,we determined the relationship among lncRNA-m18as1,miR-18a-5p,and the Smad2/3 pathway.Overall,we found that lncRNA-m18as1 acts as a molecular sponge of miR-18a-5p to regulate the synthesis and secretion of FSH through the Smad2/3 pathway.展开更多
Sound transmission occurs in the cochlea,a complex and ingenious subdivision in the inner ear.The structure of the cochlea develops structurally and functionally by the time before two postnatal weeks(the time of hear...Sound transmission occurs in the cochlea,a complex and ingenious subdivision in the inner ear.The structure of the cochlea develops structurally and functionally by the time before two postnatal weeks(the time of hearing onset)in mice(Geal-Dor et al.,1993).Greater epithelial ridge(GER,also known as Kolliker's organ)is a transient cochlear structure containing a group of columnar epithelial supporting cells surrounding the inner hair cells(IHCs).展开更多
Insufficient remyelination due to impaired oligodendrocyte precursor cell(OPC)differentiation and maturation is strongly associated with irreversible white matter injury(WMI)and neurological deficits.We analyzed whole...Insufficient remyelination due to impaired oligodendrocyte precursor cell(OPC)differentiation and maturation is strongly associated with irreversible white matter injury(WMI)and neurological deficits.We analyzed whole transcriptome expression to elucidate the potential role and underlying mechanism of action of lipocalin-2(LCN2)in OPC differentiation and WMI and identified the receptor SCL22A17 and downstream transcription factor early growth response protein 1(EGR1)as the key signals contributing to LCN2-mediated insufficient OPC remyelination.In LCN-knockdown and OPC EGR1 conditional-knockout mice,we discovered enhanced OPC differentiation in developing and injured white matter(WM);consistent with this,the specific inactivation of LCN2/SCl22A17/EGR1 signaling promoted remyelination and neurological recovery in both atypical,acute WMI due to subarachnoid hemorrhage and typical,chronic WMI due to multiple sclerosis.This potentially represents a novel strategy to enhance differentiation and remyelination in patients with white matter injury.展开更多
Sophorae Flavescentis Radix(SFR)is a medicinal herb with many functions that are involved in anti-inflammation,antinociception,and anticancer.SFR is also used to treat a variety of itching diseases.Matrine(MT)is one o...Sophorae Flavescentis Radix(SFR)is a medicinal herb with many functions that are involved in anti-inflammation,antinociception,and anticancer.SFR is also used to treat a variety of itching diseases.Matrine(MT)is one of the main constituents in SFR and also has the effect of relieving itching,but the antipruritic mechanism is still unclear.Here,we investigated the effect of MT on antipruritus.In acute and chronic itch models,MT significantly inhibited the scratching behavior not only in acute itching induced by histamine(His),chloroquine(CQ)and compound 48/80 with a dose-depended manner,but also in the chronic pruritus models of Atopic dermatitis(AD)and Acetone-ether-water(AEW)in mice.Furthermore,MT can be detected in the blood after intraperitoneal injection(i.p.)and subcutaneous injection(s.c.).Finally,electrophysiological and calcium image results show that MT inhibits the excitatory synaptic transmission from dorsal root ganglion(DRG)to the dorsal horn of the spinal cord by suppressing presynaptic N-type calcium channels.Taken together,we believe that MT is a novel drug candidate in treating pruritus diseases,especially for histamine-independent and chronic pruritus,which might be attributed to inhibition of presynaptic N-type calcium channels.展开更多
Airway smooth muscle(ASM)has developed a mechanical adaption mechanism by which it transduces force and responds to environmental forces,which is essential for periodic breathing.Cytoskeletal reorganization has been i...Airway smooth muscle(ASM)has developed a mechanical adaption mechanism by which it transduces force and responds to environmental forces,which is essential for periodic breathing.Cytoskeletal reorganization has been implicated in this process,but the regulatory mechanism remains to be determined.We here observe that ASM abundantly expresses cytoskeleton regulators Limk1 and Limk2,and their expression levels are further upregulated in chronic obstructive pulmonary disease(COPD)animals.By establishing mouse lines with deletions of Limk1 or Limk2,we analyse the length-sensitive contraction,F/Gactin dynamics,and F-actin pool of mutant ASM cells.As LIMK1 phosphorylation does not respond to the contractile stimulation,LIMK1-deficient ASM develops normal maximal force,while LIMK2 or LIMK1/LIMK2 deficient ASMs show approximately 30%inhibition.LIMK2 deletion causes a significant decrease in cofilin phosphorylation along with a reduced F/G-actin ratio.As LIMK2 functions independently of cross-bridge movement,this observation indicates that LIMK2 is necessary for F-actin dynamics and hence force transduction.Moreover,LIMK2-deficient ASMs display abolishes stretching-induced suppression of 5-hydroxytryptamine(5-HT)but not acetylcholine-evoks force,which is due to the differential contraction mechanisms adopted by the agonists.We propose that LIMK2-mediated cofilin phosphorylation is required for membrane cytoskeleton reorganization that is necessary for ASM mechanical adaption including the 5-HT-evoked length-sensitive effect.展开更多
Vascular development is essential for the establishment of the circulatory system during embryonic development and requires the proliferation of endothelial cells.However,the underpinning regulatory mechanisms are not...Vascular development is essential for the establishment of the circulatory system during embryonic development and requires the proliferation of endothelial cells.However,the underpinning regulatory mechanisms are not well understood.Here,we report that geranylgeranyl pyrophosphate(GGPP),a metabolite involved in protein geranylgeranylation,plays an indispensable role in embryonic vascular development.GGPP is synthesized by geranylgeranyl pyrophosphate synthase(GGPPS)in the mevalonate pathway.The selective knockout of Ggpps in endothelial cells led to aberrant vascular development and embryonic lethality,resulting from the decreased proliferation and enhanced apoptosis of endothelial cells during vasculogenesis.The defect in protein geranylgeranylation induced by GGPP depletion inhibited the membrane localization of Rho A and enhanced yes-associated protein(YAP)phosphorylation,thereby prohibiting the entry of YAP into the nucleus and the expression of YAP target genes related to cell proliferation and the antiapoptosis process.Moreover,inhibition of the mevalonate pathway by simvastatin induced endothelial cell proliferation defects and apoptosis,which were ameliorated by GGPP.Geranylgeraniol(GGOH),a precursor of GGPP,ameliorated the harmful effects of simvastatin on vascular development of developing fetuses in pregnant mice.These results indicate that GGPP-mediated protein geranylgeranylation is essential for endothelial cell proliferation and the antiapoptosis process during embryonic vascular development.展开更多
基金supported by The Beljanski Foundation(to JY)and Military Laboratory Animal Fund(Grant No.SYDW[2017]15to TF)。
文摘Objective:Herbal medicine is an important therapeutic option for benign prostatic hyperplasia(BPH),a common disease in older men that can seriously affect their quality of life.Currently,it is crucial to develop agents with strong efficacy and few side effects.Herein we investigated the effects of the extract of Rauwolfia vomitoria,a shrub grown in West Africa,on BPH.Methods:Rats with testosterone-induced BPH were treated with R.vomitoria.Prostates were histologically analyzed by Hematoxylin and eosin staining.Proliferation index and the expression levels of androgen receptor and its associated proteins were quantified through immunohistochemistry and immunoblotting.Androgen receptor target genes were examined by quantitative real-time polymerase chain reaction.The sperm count and body weight of rats were also measured.Results:The oral administration of R.vomitoria extract significantly reduced the prostate weight and prostate weight index in BPH rats,supported by the decreased thickness of the prostate epithelial layer and increased lumen size.Similar effects were observed in the BPH rats treated with the reference drug,finasteride.R.vomitoria extract significantly reduced the testosterone-induced proliferation markers,including proliferating cell nuclear antigen and cyclin D1,in the prostate glands of BPH rats;it also reduced levels of androgen receptor,its associated protein steroid 5 a-reductase 1 and its downstream target genes(FK506-binding protein 5 and matrix metalloproteinase 2).Notably,compared with the finasteride group,R.vomitoria extract did not significantly reduce sperm count.Conclusion:R.vomitoria suppresses testosterone-induced BPH development.Due to its milder side effects,R.vomitoria could be a promising therapeutic agent for BPH.
基金supported by the National Natural Science Foundation of China(82171136 and 92368110 to G.W.,82201291 to G.-J.Z.,82192861 to Z.X.,81970884 and 82192862 to X.G.)the Natural Science Foundation of Jiangsu Province(BK20220188 to Q.L.,BK20220189 to G.-J.Z.)the Fundamental Research Funds for the Central Universities(021414380533 to G.W.).
文摘Hearing relies on the structural and functional integrity of cochlear hair cells,particularly their apical F-actin-filled stereocilia.Phospholipid scramblases are important for maintaining membrane asymmetry,but their roles in the stereocilia and auditory functions are not fully understood.Here,we identify Plscr5 as a downstream target of the transcription factor POU4F3 essential for hair cell function,whose mutation causes human DFNA15 deafness.Plscr5 knockout mice exhibit progressive hearing loss due to stereocilia degeneration and hair cell loss.Functional analyses reveal that PLSCR5 contributes to phosphatidylserine externalization in hair cell apical membranes,particularly in inner hair cells,and is important for outer hair cell and stereocilia maintenance.Our findings highlight PLSCR5 as an important downstream effector of POU4F3 and regulator of phosphatidylserine externalization and membrane dynamics required for auditory functions.
基金supported by the National Key R&D Program of China(No.2022YFA1303600 and No.2023YFC2306800)the National Natural Science Foundation of China(No.82372235 and No.82272315)the Sanming Project of Medicine in Shenzhen(No.SZSM202311032).
文摘The persistence of covalently closed circular DNA(cccDNA)in hepatitis B virus(HBV)-infected hepatocytes remains a major obstacle to effective antiviral treatment.Understanding the molecular mechanisms regulating HBV cccDNA transcription is essential for developing novel therapeutic strategies.In this study,we investigated the role of RNA binding motif protein 25(RBM25)in HBV replication,focusing on its interaction with cccDNA and its regulation of host transcription factors.The results demonstrated that RBM25 knockdown markedly inhibited HBV replication,reducing levels of HBV DNA,hepatitis B e antigen(HBeAg),hepatitis B surface antigen(HBsAg),HBV RNA,and L-HBs in HBV-replicating and infected cell models.Consistent results were observed in a mouse model hydrodynamically injected with 1.2HBV plasmid.Conversely,RBM25 overexpression significantly enhanced HBV replication.Mechanistically,RBM25 promoted HBV promoter activities by binding to cccDNA through its RE/RD and PWI domains.This effect was mediated by increased Yin Yang 1(YY1)expression,which enhanced acetylation of cccDNA-bound histones,promoting HBV transcription.Furthermore,RBM25 expression was upregulated and translocated to the nucleus following core protein expression and accumulation,while overexpression of RBM25 promoted core protein degradation.In conclusion,this study demonstrates that RBM25 is a novel host factor that enhances HBV replication by upregulating YY1-dependent transcriptional activation of cccDNA.It also reveales a reciprocal regulatory mechanism between the HBV core protein and RBM25,which helps sustain HBV replication.
基金supported by grants from the National Key R&D Program of China(2019YFA0801603)the Guangdong High Level Innovation Research Institute(2021B0909050004)+2 种基金the National Natural Science Foundation of China(32330044,32170951,82201615,and 82101393)the Natural Science Foundation of Jiangsu Province(BK20201255 and BK20210008)the Fundamental Research Funds for the Central Universities(021414380533).
文摘Accurate timing of myelination is crucial for the proper functioning of the central nervous system. Here, we identified a de novo heterozygous mutation in TMEM63A (c.1894G>A;p. Ala632Thr) in a 7-year-old boy exhibiting hypomyelination. A Ca2+ influx assay suggested that this is a loss-of-function mutation. To explore how TMEM63A deficiency causes hypomyelination, we generated Tmem63a knockout mice. Genetic deletion of TMEM63A resulted in hypomyelination at postnatal day 14 (P14) arising from impaired differentiation of oligodendrocyte precursor cells (OPCs). Notably, the myelin dysplasia was transient, returning to normal levels by P28. Primary cultures of Tmem63a^(−/−) OPCs presented delayed differentiation. Lentivirus-based expression of TMEM63A but not TMEM63A_A632T rescued the differentiation of Tmem63a^(−/−) OPCs in vitro and myelination in Tmem63a^(−/−) mice. These data thus support the conclusion that the mutation in TMEM63A is the pathogenesis of the hypomyelination in the patient. Our study further demonstrated that TMEM63A-mediated Ca^(2+) influx plays critical roles in the early development of myelin and oligodendrocyte differentiation.
文摘Looking back a decade ago when I decided to use ＂model animal＂ to name our newly established institute, my outrageous boldness can only be described by the old Chinese slang, ＂newborn calf could never sense the danger of tiger＂. Happily, my courageous belief, along with the hard work of my colleagues at Model Animal Research Center of Nanjing University, paid off eventually. We have witnessed the great progress in this research field in China in the past 10 years. This issue of Science China Life Sciences samplings some of these accomplishments.
基金supported by the National Natural Science Funding of China (31272311 and 31330034 to M.S.Z.)
文摘Several factors have been implicated in obesity-related hypertension, but the genesis of the hypertension is largely unknown. In this study, we found a significantly upregulated expression of CPI-17(C-kinasepotentiated protein phosphatase 1 inhibitor of 17 kDa) and protein kinase C(PKC) isoforms in the vascular smooth muscles of high-fat diet(HFD)-fed obese mice. The obese wild-type mice showed a significant elevation of blood pressure and enhanced calcium-sensitized contraction of vascular smooth muscles. However, the obese CPI-17-deficient mice showed a normotensive blood pressure, and the calcium-sensitized contraction was consistently reduced. In addition, the mutant muscle displayed an abolished responsive force to a PKC activator and a 30%-50% reduction in both the initial peak force and sustained force in response to various G protein-coupled receptor(GPCR) agonists. Our observations showed that CPI-17-mediated calcium sensitization is mediated through a GPCR/PKC/CPI-17/MLCP/RLC signaling pathway. We therefore propose that the upregulation of CPI-17-mediated calcium-sensitized vasocontraction by obesity contributes to the development of obesity-related hypertension.
基金This study was supported by the National Key Basic Research Program of China,No.2017YFA0104701(to XSG)the National Natural Science Foundation of China,No.31730031(to XSG),81870975(to SLZ)+1 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)(to XSG)the Natural Science Foundation of Jiangsu Province,No.BK20202013(to XSG).
文摘Recovery from injury to the peripheral nervous system is different from that of the central nervous system in that it can lead to gene reprogramming that can induce the expression of a series of regeneration-associated genes.This eventually leads to axonal regeneration of injured neurons.Although some regeneration-related genes have been identified,the regulatory network underlying axon regeneration remains largely unknown.To explore the regulator of axon regeneration,we performed RNA sequencing of lumbar L4 and L5 dorsal root ganglion(DRG)neurons at different time points(0,3,6,12 hours,1,3 and 7 days)after rat sciatic nerve crush.The isolation of neurons was carried out by laser capture microscopy combined with NeuN immunofluorescence staining.We found 1228 differentially expressed genes in the injured sciatic nerve tissue.The hub genes within these differentially expressed genes include Atf3,Jun,Myc,Ngf,Fgf2,Ezh2,Gfap and Il6.We verified that the expression of the enhancer of zeste homologue 2 gene(Ezh2)was up-regulated in DRG neurons after injury,and this up-regulation differed between large-and small-sized dorsal root ganglion neurons.To investigate whether the up-regulation of Ezh2 impacts axonal regeneration,we silenced Ezh2 with siRNA in cultured DRG neurons and found that the growth of the newborn axons was repressed.In our investigation into the regulatory network of Ezh2 by interpretive phenomenal analysis,we found some regulators of Ezh2(including Erk,Il6 and Hif1a)and targets(including Atf3,Cdkn1a and Smad1).Our findings suggest that Ezh2,as a nerve regeneration-related gene,participates in the repair of the injured DRG neurons,and knocking down the Ezh2 in vitro inhibits the axonal growth of DRG neurons.All the experimental procedures approved by the Administration Committee of Experimental Animals of Jiangsu Province of China(approval No.S20191201-201)on March 21,2019.
基金supported by grants from the National Natural Science Foundation of China (31272311 and 31330034) to M.S.Z.
文摘As a critical guanine nucleotide exchange factor(GEF) regulating neurite outgrowth, Trio coordinates multiple processes of cytoskeletal dynamics through activating Rac1, Cdc42 and RhoA small GTPases by two GEF domains, but the in vivo roles of these GEF domains and corresponding downstream effectors have not been determined yet. We established multiple lines of knockout mice and assessed the respective roles of Trio GEF domains and Rac1 in axon outgrowth. Knockout of total Trio in cerebellar granule neurons(CGNs) led to an impaired F-actin rearrangement of growth cone and hence a retarded neurite outgrowth. Such a retardation was reproduced by inhibition of GEF1 domain or knockdown of Cdc42 and restored apparently by introduction of active Cdc42. As Rac1 deficiency did not affect the neurite outgrowth of CGNs, we suggested that Trio GEF1-mediated Cdc42 activation was required for neurite outgrowth. We established a GEF2-knockout line with deletion of all Trio isoforms except a cerebella-specific Trio8, a short isoform of Trio without GEF2 domain, and used this line as a GEF2-deficient animal model. The GEF2-deficient CGNs had a normal neurite outgrowth but abolished Netrin-1-promoted growth, without affecting Netrin-1 induced Rac1 activation. We thus suggested that Trio GEF1-mediated Cdc42 activation rather than Rac1 activation drives the F-actin dynamics necessary for neurite outgrowth, while GEF2 functions in Netrin-1-promoted neurite elongation. Our results delineated the distinct roles of Trio GEF domains in neurite outgrowth, which is instructive to understand the pathogenesis of clinical Trio-related neurodevelopmental disorders.
文摘T cells are derived from progenitor thymocytes, of which only a minority receive the appropriate TCR signal, undergo positive selection and mature. Owing to the very short lifespan of thymocytes, the prerequisite for posi- tive selection is survival. TCR signal-induced Bcl-2 expression is believed to play a dominant role in the survival of positively selecting thymocytes, but how Bcl-2 is directly regulated is unknown. Here we report that the immediate early gene （IEG） c-Fos can stimulate the expression of Bcl-2, depending on a specific AP-l-binding site in the Bcl-2 promoter. In c-Fos transgenic （Fos-Tg） mice, c-Fos binds to this site and promotes the expression of Bcl-2. As a result, Fos-Tg thymocytes exhibited enhanced survival, and more mature single-positive （SP） thymocytes were generated, even on a unique TCR background. The TCR repertoire remained normal in Fos-Tg mice. Our results identified c-Fos as the mediator of the stimulatory effect of TCR signaling on Bcl-2 expression. Therefore, c-Fos, as an IEG, because of its early response ability, can quickly rescue the survival of short-lived thymocytes during positive selection. Our results provide novel insight into the mechanism regulating the survival of positively selecting thymocytes.
基金supported by the National Natural Science Foundation of China,Nos. 31730031 and 32130060the National Major Project of Research and Development,No. 2017YFA0104700the Natural Science Foundation of Jiangsu Province,No. BK20202013 (all to XSG)。
文摘The key regulators and regeneration-associated genes involved in axonal regeneration of neurons after injury have not been clarified.In high-throughput sequencing,various factors influence the final sequencing results,including the number and size of cells,the depth of sequencing,and the method of cell separation.There is still a lack of research on the detailed molecular expression profile during the regeneration of dorsal root ganglion neuron axon.In this study,we performed lase r-capture microdissection coupled with RNA sequencing on dorsal root ganglion neurons at 0,3,6,and 12 hours and 1,3,and 7 days after sciatic nerve crush in rats.We identified three stages after dorsal root ganglion injury:early(3-12 hours),pre-regeneration(1 day),and regeneration(3-7 days).Gene expression patterns and related function enrichment res ults showed that one module of genes was highly related to axonal regeneration.We verified the up-regulation of activating transcription factor 3(Atf3),Kruppel like factor 6(Klf6),AT-rich inte raction domain 5A(Arid5α),CAMP responsive element modulator(Crem),and FOS like 1,AP-1 transcription factor Subunit(Fosl1) in dorsal root ganglion neurons after injury.Suppressing these transcription factors(Crem,Arid5o,Fosl1 and Klf6) reduced axonal regrowth in vitro.As the hub transcription factor,Atf3 showed higher expression and activity at the preregeneration and regeneration stages.G protein-coupled estrogen receptor 1(Gper1),inte rleukin 12a(Il12α),estrogen receptor 1(ESR1),and interleukin 6(IL6) may be upstream factors that trigger the activation of Atf3 during the repair of axon injury in the early stage.Our study presents the detailed molecular expression profile during axonal regeneration of dorsal root ganglion neurons after peripheral nerve injury.These findings may provide reference for the clinical screening of molecular targets for the treatment of peripheral nerve injury.
基金supported by the National Basic Research Program of China(No.2007CB947301)the National Natural Science Foundation of China(No.30800613)Pujiang Talent(No.08PJ1407200)
文摘N-ethyl-N-nitrosourea （ENU） mutagenesis has led to the elucidation of several regulator genes for melanocyte and skin development. Here we characterized a mutant from ENU mutagenesis with similar phenotype as that of Splotch mutant, including exencephaly, spina bifida and abnormal limbs in homozygotes as well as white belly spotting and occasionally loop-tail in heterozygotes. This novel mutant was named as SpxG. Through genome-wide linkage analysis in backcross progenies with microsatellite markers, the SpxG was confined to a region between DIMIT415 and DIMIT7 on chromosome 1, where notable Pax3 gene was located. Direct sequencing revealed that SpxG carried a nucleotide A894G missense transition in exon 6 of Pax3 gene that resulted in Asn to Asp substitution at amino acid 269 within the highly-conserved homeodomain （HD） DNA recognition module, which was the first point mutation found in this domain in mice. This N269D mutation impaired the transactivation capacity of Pax3 protein, but exerted no effect on Pax3 protein translation. The characterization of the new mutation expanded our understanding the transactivation and DNA-binding structure of Pax3 protein.
基金supported by the National Natural Science Foundation of China,No.31970968(to SYL)the Collegiate Natural Science Foundation of Jiangsu Province,No.16KJA310005(to SYL)+1 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions[PAPD]the Natural Science Foundation of Jiangsu Province,No.BK20200976(to XHW).
文摘Neurotrophic factors,particularly nerve growth factor,enhance neuronal regeneration.However,the in vivo applications of nerve growth factor are largely limited by its intrinsic disadvantages,such as its short biological half-life,its contribution to pain response,and its inability to cross the blood-brain barrier.Considering that let-7(human miRNA)targets and regulates nerve growth factor,and that let-7 is a core regulator in peripheral nerve regeneration,we evaluated the possibilities of let-7 application in nerve repair.In this study,anti-let-7a was identified as the most suitable let-7 family molecule by analyses of endogenous expression and regulatory relationship,and functional screening.Let-7a antagomir demonstrated biosafety based on the results of in vivo safety assessments and it entered into the main cell types of the sciatic nerve,including Schwann cells,fibroblasts and macrophages.Use of hydrogel effectively achieved controlled,localized,and sustained delivery of let-7a antagomir.Finally,let-7a antagomir was integrated into chitosan conduit to construct a chitosan-hydrogel scaffold tissue-engineered nerve graft,which promoted nerve regeneration and functional recovery in a rat model of sciatic nerve transection.Our study provides an experimental basis for potential in vivo application of let-7a.
基金This work was supported by National Naturcal Science Foundation of China （No. 30470852）The National Gongguan Project of China （21001BA710B）.
文摘Myosin light chain kinases （MLCK） phosphorylate the regulatory light chain of myosin II in thick filaments and bind to F-actin-containing thin filaments with high affinity. The ability of short myosin light chain kinase （S-MLCK） to bind F-actin is structurally attributed to the DFRXXL regions in its N-terminus. The long myosin light chain kinase （L-MLCK） has two additional DFRXXL motifs and six Ig-like modules in its N-terminal extension. The six Ig-like modules are capable of binding to stress fibers independently. Our results from the imaging analysis demonstrated that the first two intact Ig-like modules （2Ig） in N-terminal extension of L-MLCK is the minimal binding module required for microfilament binding. Binding assay confirmed that F-actin was able to bind 2Ig. Stoichiometries of 2Ig peptide were similar for myofilament or pure F-actin. The binding affinities were slightly lower than 5DFRXXL peptide as reported previously. Similar to DFRXXL peptides, the 2Ig peptide also caused efficient F-actin bundle formation in vitro. In the living cell, over-expression of 2Ig fragment increased ＂spike＂-like protrusion formation with over-bundled F-actin. Our results suggest that L-MLCK may act as a potent F-actin bundling protein via its DFRXXL region and the 2Ig region, implying that L-MLCK plays a role in cytoskeleton organization.
基金the National Key Basic Research Program of China(2017YFA0104701)the National Natural Science Foundation of China(31730031,81571198,81870975,81971170,and 81671230)+1 种基金the Natural Science Foundation of Jiangsu Province(BK20202013)the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Dear Editor,The peripheral nervous system(PNS)regenerates more easily after injury than the central nervous system(CNS)[1].Sensory neurons in the L4–L6 dorsal root ganglia(DRGs)extend axons to form the sciatic nerve along with motor axons.The DRG neuron is one of the exceptional mature neurons whose axons can regenerate after injury.
基金the National Natural Science Foundation of China(No.31872349)。
文摘Long noncoding RNAs(lncRNAs)are expressed in different species and different tissues,and perform different functions,but little is known about their involvement in the synthesis or secretion of follicle-stimulating hormone(FSH).In general,we have revealed lnc RNA-micro RNA(mi RNA)-messenger RNA(m RNA)interactions that may play important roles in rat primary pituitary cells.In this study,a new lncRNA was identified for the first time.First,we analyzed the gene expression of lncRNA-m18as1 in different tissues and different stages by reverse transcription-quantitative polymerase chain reaction(RT-qPCR)and observed the localization of lncRNA-m18as1 with fluorescence in situ hybridization,which indicated that this lncRNA was distributed mainly in the cytoplasm.Next,we used RT-qPCR and enzyme-linked immunosorbent assay(ELISA)to analyze the regulation of FSH synthesis and secretion after overexpression or knockdown of lncRNA-m18as1 and found that lncRNA-m18as1 was positively correlated with FSH synthesis and secretion.In addition,mothers against decapentaplegic homolog 2(Smad2)was highly expressed in our sequencing results.We also screened miR-18a-5p from our sequencing results as a miRNA that may bind to lncRNA-m18as1 and Smad2.We used RNA immunoprecipitation-qPCR(RIP-qPCR)and/or dual luciferase assays to confirm that lncRNA-m18as1 interacted with miR-18a-5p and miR-18a-5p interacted with Smad2.Fluorescence in situ hybridization(FISH)showed that lncRNA-m18as1 and miR-18a-5p were localized mainly in the cytoplasm.Finally,we determined the relationship among lncRNA-m18as1,miR-18a-5p,and the Smad2/3 pathway.Overall,we found that lncRNA-m18as1 acts as a molecular sponge of miR-18a-5p to regulate the synthesis and secretion of FSH through the Smad2/3 pathway.
基金supported by the National Natural Science Foundation of China(82171136 and 81970888 to G.W.,32330044 to Y.S.S.)Fundamental Research Funds for the Central Universities(021414380533toG.W.).
文摘Sound transmission occurs in the cochlea,a complex and ingenious subdivision in the inner ear.The structure of the cochlea develops structurally and functionally by the time before two postnatal weeks(the time of hearing onset)in mice(Geal-Dor et al.,1993).Greater epithelial ridge(GER,also known as Kolliker's organ)is a transient cochlear structure containing a group of columnar epithelial supporting cells surrounding the inner hair cells(IHCs).
基金supported by the National Natural Science Foundation of China(81901216 and 82030036)Southwest Hospital(SWH2018BJKJ-05 and SWH2015QN13)the Chongqing Talent Program(4139Z2391).
文摘Insufficient remyelination due to impaired oligodendrocyte precursor cell(OPC)differentiation and maturation is strongly associated with irreversible white matter injury(WMI)and neurological deficits.We analyzed whole transcriptome expression to elucidate the potential role and underlying mechanism of action of lipocalin-2(LCN2)in OPC differentiation and WMI and identified the receptor SCL22A17 and downstream transcription factor early growth response protein 1(EGR1)as the key signals contributing to LCN2-mediated insufficient OPC remyelination.In LCN-knockdown and OPC EGR1 conditional-knockout mice,we discovered enhanced OPC differentiation in developing and injured white matter(WM);consistent with this,the specific inactivation of LCN2/SCl22A17/EGR1 signaling promoted remyelination and neurological recovery in both atypical,acute WMI due to subarachnoid hemorrhage and typical,chronic WMI due to multiple sclerosis.This potentially represents a novel strategy to enhance differentiation and remyelination in patients with white matter injury.
文摘Sophorae Flavescentis Radix(SFR)is a medicinal herb with many functions that are involved in anti-inflammation,antinociception,and anticancer.SFR is also used to treat a variety of itching diseases.Matrine(MT)is one of the main constituents in SFR and also has the effect of relieving itching,but the antipruritic mechanism is still unclear.Here,we investigated the effect of MT on antipruritus.In acute and chronic itch models,MT significantly inhibited the scratching behavior not only in acute itching induced by histamine(His),chloroquine(CQ)and compound 48/80 with a dose-depended manner,but also in the chronic pruritus models of Atopic dermatitis(AD)and Acetone-ether-water(AEW)in mice.Furthermore,MT can be detected in the blood after intraperitoneal injection(i.p.)and subcutaneous injection(s.c.).Finally,electrophysiological and calcium image results show that MT inhibits the excitatory synaptic transmission from dorsal root ganglion(DRG)to the dorsal horn of the spinal cord by suppressing presynaptic N-type calcium channels.Taken together,we believe that MT is a novel drug candidate in treating pruritus diseases,especially for histamine-independent and chronic pruritus,which might be attributed to inhibition of presynaptic N-type calcium channels.
基金supported by the National Natural Science Funding of China(31272711,31330034,9184910039and 3207090129 to M.S.Z)。
文摘Airway smooth muscle(ASM)has developed a mechanical adaption mechanism by which it transduces force and responds to environmental forces,which is essential for periodic breathing.Cytoskeletal reorganization has been implicated in this process,but the regulatory mechanism remains to be determined.We here observe that ASM abundantly expresses cytoskeleton regulators Limk1 and Limk2,and their expression levels are further upregulated in chronic obstructive pulmonary disease(COPD)animals.By establishing mouse lines with deletions of Limk1 or Limk2,we analyse the length-sensitive contraction,F/Gactin dynamics,and F-actin pool of mutant ASM cells.As LIMK1 phosphorylation does not respond to the contractile stimulation,LIMK1-deficient ASM develops normal maximal force,while LIMK2 or LIMK1/LIMK2 deficient ASMs show approximately 30%inhibition.LIMK2 deletion causes a significant decrease in cofilin phosphorylation along with a reduced F/G-actin ratio.As LIMK2 functions independently of cross-bridge movement,this observation indicates that LIMK2 is necessary for F-actin dynamics and hence force transduction.Moreover,LIMK2-deficient ASMs display abolishes stretching-induced suppression of 5-hydroxytryptamine(5-HT)but not acetylcholine-evoks force,which is due to the differential contraction mechanisms adopted by the agonists.We propose that LIMK2-mediated cofilin phosphorylation is required for membrane cytoskeleton reorganization that is necessary for ASM mechanical adaption including the 5-HT-evoked length-sensitive effect.
基金supported by the National Natural Science Foundation of China(31530046 and 31771492)National Science and Technology Major Project(SQ2018YFC100242)+2 种基金Key R&D Program of Jiangsu Province(BE2017708)Fundamental Research Funds for the Central Universities(021414380469)Nature Science Foundation of Jiangsu Province(BK20200061)。
文摘Vascular development is essential for the establishment of the circulatory system during embryonic development and requires the proliferation of endothelial cells.However,the underpinning regulatory mechanisms are not well understood.Here,we report that geranylgeranyl pyrophosphate(GGPP),a metabolite involved in protein geranylgeranylation,plays an indispensable role in embryonic vascular development.GGPP is synthesized by geranylgeranyl pyrophosphate synthase(GGPPS)in the mevalonate pathway.The selective knockout of Ggpps in endothelial cells led to aberrant vascular development and embryonic lethality,resulting from the decreased proliferation and enhanced apoptosis of endothelial cells during vasculogenesis.The defect in protein geranylgeranylation induced by GGPP depletion inhibited the membrane localization of Rho A and enhanced yes-associated protein(YAP)phosphorylation,thereby prohibiting the entry of YAP into the nucleus and the expression of YAP target genes related to cell proliferation and the antiapoptosis process.Moreover,inhibition of the mevalonate pathway by simvastatin induced endothelial cell proliferation defects and apoptosis,which were ameliorated by GGPP.Geranylgeraniol(GGOH),a precursor of GGPP,ameliorated the harmful effects of simvastatin on vascular development of developing fetuses in pregnant mice.These results indicate that GGPP-mediated protein geranylgeranylation is essential for endothelial cell proliferation and the antiapoptosis process during embryonic vascular development.
