Neural stem cell-derived exosomes regulate cell proliferation,migration,and cell death of brain microvascular endothelial cells via the miR-9/Hes1 axis under hypoxia

Background:Our previous study found that mouse embryonic neural stem cell(NSC)-derived exosomes(EXOs)regulated NSC differentiation via the miR-9/Hes1 axis.However,the effects of EXOs on brain microvascular endothelial cell(BMEC)dysfunction via the miR-9/Hes1 axis remain unknown.Therefore,the current study aimed to determine the effects of EXOs on BMEC proliferation,migration,and death via the miR-9/Hes1 axis.Methods:Immunofluorescence,quantitative real-time polymerase chain reaction,cell counting kit-8 assay,wound healing assay,calcein-acetoxymethyl/propidium iodide staining,and hematoxylin and eosin staining were used to determine the role and mechanism of EXOs on BMECs.Results:EXOs promoted BMEC proliferation and migration and reduced cell death under hypoxic conditions.The overexpression of miR-9 promoted BMEC prolifera-tion and migration and reduced cell death under hypoxic conditions.Moreover,miR-9 downregulation inhibited BMEC proliferation and migration and also promoted cell death.Hes1 silencing ameliorated the effect of amtagomiR-9 on BMEC proliferation and migration and cell death.Hyperemic structures were observed in the regions of the hippocampus and cortex in hypoxia-induced mice.Meanwhile,EXO treatment improved cerebrovascular alterations.Conclusion:NSC-derived EXOs can promote BMEC proliferation and migra-tion and reduce cell death via the miR-9/Hes1 axis under hypoxic conditions.Therefore,EXO therapeutic strategies could be considered for hypoxia-induced vascular injury.

Small extracellular vesicles from hypoxia-preconditioned bone marrow mesenchymal stem cells attenuate spinal cord injury via miR-146a-5p-mediated regulation of macrophage polarization

Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.

Prox1 Suppresses Proliferation and Drug Resistance of Retinoblastoma Cells via Targeting Notch1

Objective Retinoblastoma(RB)is a prevalent type of eye cancer in youngsters.Prospero homeobox 1(Prox1)is a homeobox transcriptional repressor and downstream target of the proneural gene that is relevant in lymphatic,hepatocyte,pancreatic,heart,lens,retinal,and cancer cells.The goal of this study was to investigate the role of Prox1 in RB cell proliferation and drug resistance,as well as to explore the underlying Notch1 mechanism.Methods Human RB cell lines(SO-RB50 and Y79)and a primary human retinal microvascular endothelial cell line(ACBRI-181)were used in this study.The expression of Prox1 and Notch1 mRNA and protein in RB cells was detected using quantitative real time-polymerase chain reaction(RT-qPCR)and Western blotting.Cell proliferation was assessed after Prox1 overexpression using the Cell Counting Kit-8 and the MTS assay.Drug-resistant cell lines(SO-RB50/vincristine)were generated and treated with Prox1 to investigate the role of Prox1 in drug resistance.We employed pcDNA-Notch1 to overexpress Notch1 to confirm the role of Notch1 in the protective function of Prox1.Finally,a xenograft model was constructed to assess the effect of Prox1 on RB in vivo.Results Prox1 was significantly downregulated in RB cells.Overexpression of Prox1 effectively decreased RB cell growth while increasing the sensitivity of drug-resistant cells to vincristine.Notch1 was involved in Prox1’s regulatory effects.Notch1 was identified as a target gene of Prox1,which was found to be upregulated in RB cells and repressed by increased Prox1 expression.When pcDNA-Notch1 was transfected,the effect of Prox1 overexpression on RB was removed.Furthermore,by downregulating Notch1,Prox1 overexpression slowed tumor development and increased vincristine sensitivity in vivo.Conclusion These data show that Prox1 decreased RB cell proliferation and drug resistance by targeting Notch1,implying that Prox1 could be a potential therapeutic target for RB.

Meiotic nuclear divisions 1 suppresses the proliferation and invasion of pancreatic cancer cells via regulating H2A.X variant histone

Introduction:Among all malignant tumors of the digestive system,pancreatic carcinoma exhibits the highest mortality rate.Currently,prevention and effective treatment are urgent issues that need to be addressed.Methods:The study focused on meiotic nuclear divisions 1(MND1),integrating data from the Gene Expression Profiling Interactive Analysis(GEPIA)database with prognostic survival analysis.Simultaneously,experiments at cellular level were employed to demonstrate the effect of MND1 on the proliferation and migration of PC.The small-molecule inhibitor of MND1 was used to suppress the migration of PC cells by knocking down MND1 using small interfering RNA(siRNA)in Patu-8988 and Panc1 cell lines.Results:The results of Cell Counting Kit-8 indicated that the suppression of MND1 resulted in a decrease in cell proliferation.Wound healing and Transwell assays revealed that MND1 knockdown reduced cell migration and invasion.Flow cytometry revealed that inhibiting MND1 hindered the cell cycle.Furthermore,MND1 could stimulate the proliferation,migration,and invasion of Patu-8988 and Panc1 cells by increasing the expression of MND1.Notably,MND1 had a positive effect on H2AFX expression in PC cells.Elevated MND1 expression suggests the low overall survival rate of individuals diagnosed with PC.Conclusion:These findings suggest that MND1 has the potential to be a gene with the ability to accurately diagnose and treat PC.

Overexpression of TRPV1 activates autophagy in human lens epithelial cells under hyperosmotic stress through Ca^(2+)-dependent AMPK/mTOR pathway

●AIM:To explore whether autophagy functions as a cellular adaptation mechanism in lens epithelial cells(LECs)under hyperosmotic stress.●METHODS:LECs were treated with hyperosmotic stress at the concentration of 270,300,400,500,or 600 mOsm for 6,12,18,24h in vitro.Polymerase chain reaction(PCR)was employed for the mRNA expression of autophagyrelated genes,while Western blotting detected the targeted protein expression.The transfection of stub-RFP-sens-GFPLC3 autophagy-related double fluorescence lentivirus was conducted to detect the level of autophagy flux.Scanning electron microscopy was used to detect the existence of autolysosome.Short interfering RNA of autophagy-related gene(ATG)7,transient receptor potential vanilloid(TRPV)1 overexpression plasmid,related agonists and inhibitors were employed to their influence on autophagy related pathway.Flow cytometry was employed to test the apoptosis and intracellular Ca^(2+)level.Mitochondrial membrane potential was measured by JC-1 staining.The cell counting kit-8 assay was used to calculate the cellular viability.The wound healing assay was used to evaluate the wound closure rate.GraphPad 6.0 software was utilized to evaluate the data.●RESULTS:The hyperosmotic stress activated autophagy in a pressure-and time-dependent manner in LECs.Beclin 1 protein expression and conversion of LC3B II to LC3B I increased,whereas sequestosome-1(SQSTM1)protein expression decreased.Transient Ca^(2+)influx was stimulated caused by hyperosmotic stress,levels of mammalian target of rapamycin(mTOR)phosphorylation decreased,and the level of AMP-activated protein kinase(AMPK)phosphorylation increased in the early stage.Based on this evidence,autophagy activation through the Ca^(2+)-dependent AMPK/mTOR pathway might represent an adaptation process in LECs under hyperosmotic stress.Hyperosmotic stress decreased cellular viability and accelerated apoptosis in LECs and cellular migration decreased.Inhibition of autophagy by ATG7 knockdown had similar results.TRPV1 overexpression increased autophagy and might be crucial in the occurrence of autophagy promoted by hyperosmotic stress.●CONCLUSION:A combination of hyperosmotic stress and autophagy inhibition may be a promising approach to decrease the number of LECs in the capsular bag and pave the way for improving prevention of posterior capsular opacification and capsular fibrosis.

Silencing of Jumonji domain-containing 1C inhibits the osteogenic differentiation of bone marrow mesenchymal stem cells via nuclear factor-κB signaling

BACKGROUND Osteoporosis is a common metabolic bone disorder induced by an imbalance between osteoclastic activity and osteogenic activity.During osteoporosis,bone mesenchymal stem cells(BMSCs)exhibit an increased ability to differentiate into adipocytes and a decreased ability to differentiate into osteoblasts,resulting in bone loss.Jumonji domain-containing 1C(JMJD1C)has been demonstrated to suppress osteoclastogenesis.AIM To examine the effect of JMJD1C on the osteogenesis of BMSCs and the potential underlying mechanism.METHODS BMSCs were isolated from mouse bone marrow tissues.Oil Red O staining,Alizarin red staining,alkaline phosphatase staining and the expression of adipo-genic and osteogenic-associated genes were assessed to determine the differen-tiation of BMSCs.Bone marrow-derived macrophages(BMMs)were incubated with receptor activator of nuclear factor-kappaΒligand to induce osteoclast differentiation,and osteoclast differen-tiation was confirmed by tartrate-resistant acid phosphatase staining.Other related genes were measured via reverse transcription coupled to the quantitative polymerase chain reaction and western blotting.Enzyme-linked immunosorbent assays were used to measure the levels of inflammatory cytokines,including tumor necrosis factor alpha,interleukin-6 and interleukin-1 beta.RESULTS The osteogenic and adipogenic differentiation potential of BMSCs isolated from mouse bone marrow samples was evaluated.JMJD1C mRNA and protein expression was upregulated in BMSCs after osteoblast induction,while p-nuclear factor-κB(NF-κB)and inflammatory cytokines were not significantly altered.Knockdown of JMJD1C repressed osteogenic differentiation and enhanced NF-κB activation and inflammatory cytokine release in BMSCs.Moreover,JMJD1C expression decreased during BMM osteoclast differentiation.CONCLUSION The JMJD1C/NF-κB signaling pathway is potentially involved in BMSC osteogenic differentiation and may play vital roles in the pathogenesis of osteoporosis.

Effect of ginsenoside Rg1 on hematopoietic stem cells in treating aplastic anemia in mice via MAPK pathway

BACKGROUND Aplastic anemia(AA)presents a significant clinical challenge as a life-threatening condition due to failure to produce essential blood cells,with the current the-rapeutic options being notably limited.AIM To assess the therapeutic potential of ginsenoside Rg1 on AA,specifically its protective effects,while elucidating the mechanism at play.METHODS We employed a model of myelosuppression induced by cyclophosphamide(CTX)in C57 mice,followed by administration of ginsenoside Rg1 over 13 d.The invest-igation included examining the bone marrow,thymus and spleen for pathological changes via hematoxylin-eosin staining.Moreover,orbital blood of mice was collected for blood routine examinations.Flow cytometry was employed to identify the impact of ginsenoside Rg1 on cell apoptosis and cycle in the bone marrow of AA mice.Additionally,the study further evaluated cytokine levels with enzyme-linked immunosorbent assay and analyzed the expression of key proteins in the MAPK signaling pathway via western blot.RESULTS Administration of CTX led to significant damage to the bone marrow’s structural integrity and a reduction in hematopoietic cells,establishing a model of AA.Ginsenoside Rg1 successfully reversed hematopoietic dysfunction in AA mice.In comparison to the AA group,ginsenoside Rg1 provided relief by reducing the induction of cell apoptosis and inflammation factors caused by CTX.Furthermore,it helped alleviate the blockade in the cell cycle.Treatment with ginsenoside Rg1 significantly alleviated myelosuppression in mice by inhibiting the MAPK signaling pathway.CONCLUSION This study suggested that ginsenoside Rg1 addresses AA by alleviating myelosuppression,primarily through modulating the MAPK signaling pathway,which paves the way for a novel therapeutic strategy in treating AA,highlighting the potential of ginsenoside Rg1 as a beneficial intervention.

Influence of Angiotensin II on α1-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells

Angiotensin II (Ang II) is the main mediator of the Renin-Angiotensin-System acting on AT1 and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of Ang II on the expression and function of α1-adrenergic receptors (α1-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24 h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. Ang II was added (1 × 10−5 M), and in some experiments, 5-Methylurapidil (α1A-AR antagonist), AH11110A (α1B-AR antagonist), or BMY-7378 (α1D-AR antagonist), were used to identify the α1-AR involved in the response. Desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the Ang II action. α1D-AR was protected from desensitization by BMY-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to Ang II and α1-ARs proteins were evaluated. α1D-AR increased at 30 and 60 min post Ang II exposure, the α1A-AR diminished from 1 to 4 h, while α1B-AR remained unchanged over 24 h of Ang II exposure. Ang II induced an increase of α1D-AR at short times, and BMY-7378 protected α1D-AR from desensitization.

Ultrafine ordered L1_(2)-Pt-Co-Mn ternary intermetallic nanoparticles as high-performance oxygen-reduction electrocatalysts for practical fuel cells

The long-range periodically ordered atomic structures in intermetallic nanoparticles(INPs)can significantly enhance both the electrocatalytic activity and electrochemical stability toward the oxygen reduction reaction(ORR)compared to the disordered atomic structures in ordinary solid-solution alloy NPs.Accordingly,through a facile and scalable synthetic method,a series of carbon-supported ultrafine Pt_3Co_(x)Mn_(1-x)ternary INPs are prepared in this work,which possess the"skin-like"ultrathin Pt shells,the ordered L1_(2) atomic structure,and the high-even dispersion on supports(L1_(2)-Pt_3Co_(x)Mn_(1-x)/~SPt INPs/C).Electrochemical results present that the composition-optimized L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C exhibits the highest electrocata lytic activity among the series,which are also much better than those of the pristine ultrafine Pt/C.Besides,it also has a greatly enhanced electrochemical stability.In addition,the effects of annealing temperature and time are further investigated.More importantly,such superior ORR electrocatalytic performance of L1_(2)-Pt_3Co_(0.7)Mn_(0.3)/~SPt INPs/C are also well demonstrated in practical fuel cells.Physicochemical characterization analyses further reveal the major origins of the greatly enhanced ORR electrocata lytic performance:the Pt-Co-Mn alloy-induced geometric and ligand effects as well as the extremely high L1_(2) atomic-ordering degree.This work not only successfully develops a highly active and stable ordered ternary intermetallic ORR electrocatalyst,but also elucidates the corresponding"structure-function"relationship,which can be further applied in designing other intermetallic(electro)catalysts.

TM9SF1 is implicated in promoting the proliferation and invasion of bladder cancer cells

Zhuo et al looked into the part of transmembrane 9 superfamily member 1(TM9SF1)in bladder cancer(BC),and evaluated if it can be used as a therapeutic target.They created a permanent BC cell line and tested the effects of TM9SF1 overexpression and suppression on BC cell growth,movement,invasion,and cell cycle advancement.Their results show that TM9SF1 can boost the growth,movement,and invasion of BC cells and their access into the G2/M stage of the cell cycle.This research gives a novel direction and concept for targeted therapy of BC.

Ghrelin regulates insulin resistance by targeting insulin-like growth factor-1 receptor via miR-455-5p in hepatic cells

Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial cells.However,the functional role of GGT5 in the development of Alzheimer’s disease remains unclear.This study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying mechanism.We observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse model.Additionally,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive deficits.Interestingly,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 mice.This effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa B.Our findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 mice.These findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction

BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

外周血CD4^(+)PD-1^(+)Tcells及CD4^(+)T淋巴细胞ATP含量与复发性卵巢癌疗效的相关性分析

目的 探讨外周血CD4^(+)程序性细胞死亡受体-1(PD-1)^(+)T cells及CD4^(+)T淋巴细胞三磷酸腺苷(ATP)含量与复发性卵巢癌疗效的相关性。方法 选取30例复发性卵巢癌患者为复发组,30例未复发卵巢癌患者为非复发组;另选取30名同期体检健康者作为对照组。评估外周血CD4^(+)PD-1^(+)T cells及CD4^(+)T淋巴细胞ATP含量与复发性卵巢癌疗效的相关性。结果 复发组和非复发组的CD4^(+)PD-1^(+)T cells较对照组明显升高(P<0.05)。复发组和非复发组的CD4^(+)T淋巴细胞ATP含量较对照组明显降低(P<0.05)。复发组治疗后CD4^(+)PD-1^(+)Tcells显著低于治疗前(P<0.05),治疗后CD4^(+)T淋巴细胞ATP含量显著高于治疗前(P<0.05)。CD4^(+)PD-1^(+)T cells与复发性卵巢癌疗效成负相关(r=-0.393,P=0.039),CD4^(+)T淋巴细胞ATP含量与复发性卵巢癌疗效成正相关(r=0.449,P=0.031)。结论 复发性卵巢癌患者外周血CD4^(+)PD-1^(+)T cells及CD4^(+)T淋巴细胞ATP含量与疗效密切相关。

TM9SF1 promotes bladder cancer cell growth and infiltration

BACKGROUND Bladder cancer(BC)is the most common urological tumor.It has a high recur-rence rate,displays tutor heterogeneity,and resists chemotherapy.Furthermore,the long-term survival rate of BC patients has remained unchanged for decades,which seriously affects the quality of patient survival.To improve the survival rate and prognosis of BC patients,it is necessary to explore the molecular mechanisms of BC development and progression and identify targets for treatment and intervention.Transmembrane 9 superfamily member 1(TM9SF1),also known as MP70 and HMP70,is a member of a family of nine transmembrane superfamily proteins,which was first identified in 1997.TM9SF1 can be expressed in BC,but its biological function and mechanism in BC are not clear.AIM To investigate the biological function and mechanism of TM9SF1 in BC.Overexpression of TM9SF1 increased the in vitro proliferation,migration,and invasion of BC cells by promoting the entry of BC cells into the G2/M phase.Silencing of TM9SF1 inhibited in vitro proliferation,migration,and invasion of BC cells and blocked BC cells in the G1 phase.CONCLUSION TM9SF1 may be an oncogene in BC.

PbGIF1 promoting cell-proliferation in pear fruit is transcriptionally activated by Pb RR1

As a cell proliferation regulator involved in wide biological processes in plants,GRF-INTERACTING FACTOR(GIF)controls different tissues development.However,whether GIF participates in fruit development remains unclear.According to transcriptome data,we identified PbGIF1was highly expressed during fruit development in cytokinins induced parthenocarpy pear.In the present study,the biofunction of PbGIF1 was initially verified.Overexpression of PbGIF1 promoted fruit size of transgenic tomato.The size of flesh fruit was not affected by cell expansion but the cell proliferation was promoted by overexpressing Pb GIF1.The accelerated cell proliferation process was also observed in PbGIF1-overexpressed transgenic pear fruit calli.The transcriptional regulation of cytokinins on PbGIF1 was further confirmed by exogenous CPPU treatments in pear fruitlets.To investigate the underlying mechanism,the cytokinins-responded factor,PbRR1,was further focused on.The results of Yeast-one-hybrid assay suggested that PbRR1 can bind to the promoter sequence of PbGIF1.The transcriptional activation of PbRR1 on PbGIF1 was also confirmed by Dual-Luciferase assays.Taken together,the results showed that cytokinins control pear fruit development via the transcriptional activation of PbGIF1 by PbRR1.

TuBG1 promotes hepatocellular carcinoma via ATR/P53-apoptosis and cycling pathways

Background:As reported,γ-tubulin(TuBG1)is related to the occurrence and development of various types of malignant tumors.However,its role in hepatocellular cancer(HCC)is not clear.The present study was to investigate the relationship between TuBG1 and clinical parameters and survival in HCC patients.Methods:The correlation between TuBG1 and clinical parameters and survival in HCC patients was ex-plored by bioinformatics analysis.Immunohistochemistry was used for the verification.The molecular function of TuBG1 was measured using colony formation,scratch assay,trans-well assay and flow cytometry.Gene set enrichment analysis(GSEA)was used to pick up the enriched pathways,followed by investigating the target pathways using Western blotting.The tumor-immune system interactions and drug bank database(TISIDB)was used to evaluate TuBG1 and immunity.Based on the TuBG1-related immune genes,a prognostic model was constructed and was further validated internally and externally.Results:The bioinformatic analysis found high expressed TuBG1 in HCC tissue,which was confirmed us-ing immunohistochemistry and Western blotting.After silencing the TuBG1 in HCC cell lines,more G1 arrested cells were found,cell proliferation and invasion were inhibited,and apoptosis was promoted.Furthermore,the silence of TuBG1 increased the expressions of Ataxia-Telangiectasia and Rad-3(ATR),phospho-P38 mitogen-activated protein kinase(P-P38MAPK),phospho-P53(P-P53),B-cell lymphoma-2 associated X protein(Bax),cleaved caspase 3 and P21;decreased the expressions of B-cell lymphoma-2(Bcl-2),cyclin D1,cyclin E2,cyclin-dependent kinase 2(CDK2)and CDK4.The correlation analysis of immunohistochemistry and clinical parameters and survival data revealed that TuBG1 was negatively corre-lated with the overall survival.The constructed immune prognosis model could effectively evaluate the prognosis.Conclusions:The increased expression of TuBG1 in HCC is associated with poor prognosis,which might be involved in the occurrence and development of HCC.

Prohibitin 1 inhibits cell proliferation and induces apoptosis via the p53-mediated mitochondrial pathway in vitro

BACKGROUND Prohibitin 1(PHB1)has been identified as an antiproliferative protein that is highly conserved and ubiquitously expressed,and it participates in a variety of essential cellular functions,including apoptosis,cell cycle regulation,prolifera-tion,and survival.Emerging evidence indicates that PHB1 may play an important role in the progression of hepatocellular carcinoma(HCC).However,the role of PHB1 in HCC is controversial.AIM To investigate the effects of PHB1 on the proliferation and apoptosis of human HCC cells and the relevant mechanisms in vitro.METHODS HCC patients and healthy individuals were enrolled in this study according to the inclusion and exclusion criteria;then,PHB1 levels in the sera and liver tissues of these participates were determined using ELISA,RT-PCR,and immunohistoche-mistry.Human HepG2 and SMMC-7721 cells were transfected with the pEGFP-PHB1 plasmid and PHB1-specific shRNA(shRNA-PHB1)for 24-72 h.Cell prolif-eration was analysed with an MTT assay.Cell cycle progression and apoptosis were analysed using flow cytometry(FACS).The mRNA and protein expression levels of the cell cycle-related molecules p21,Cyclin A2,Cyclin E1,and CDK2 and the cell apoptosis-related molecules cytochrome C(Cyt C),p53,Bcl-2,Bax,caspase 3,and caspase 9 were measured by real-time PCR and Western blot,respectively.RESULTS Decreased levels of PHB1 were found in the sera and liver tissues of HCC patients compared to those of healthy individuals,and decreased PHB1 was positively correlated with low differentiation,TNM stage III-IV,and alpha-fetoprotein≥400μg/L.Overexpression of PHB1 significantly inhibited human HCC cell proliferation in a time-dependent manner.FACS revealed that the overexpression of PHB1 arrested HCC cells in the G0/G1 phase of the cell cycle and induced apoptosis.The proportion of cells in the G0/G1 phase was significantly increased and the proportion of cells in the S phase was decreased in HepG2 cells that were transfected with pEGFP-PHB1 compared with untreated control and empty vector-transfected cells.The percentage of apoptotic HepG2 cells that were transfected with pEGFP-PHB1 was 15.41%±1.06%,which was significantly greater than that of apoptotic control cells(3.65%±0.85%,P<0.01)and empty vector-transfected cells(4.21%±0.52%,P<0.01).Similar results were obtained with SMMC-7721 cells.Furthermore,the mRNA and protein expression levels of p53,p21,Bax,caspase 3,and caspase 9 were increased while the mRNA and protein expression levels of Cyclin A2,Cy-clin E1,CDK2,and Bcl-2 were decreased when PHB1 was overexpressed in human HCC cells.However,when PHB1 was upregulated in human HCC cells,Cyt C expression levels were increased in the cytosol and decreased in the mitochondria,which indicated that Cyt C had been released into the cytosol.Conversely,these effects were reversed when PHB1 was knocked down.CONCLUSION PHB1 inhibits human HCC cell viability by arresting the cell cycle and inducing cell apoptosis via activation of the p53-mediated mitochondrial pathway.

Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro

BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital resource.Nicotinamide(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet known.As a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and differentiation.However,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or cells.We propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of HSCs.AIM To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and differentiation.METHODS CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental requirements.Flow cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured cells.Real-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant enzymes.Dichloro-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead array.RESULTS Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all P<0.05).The ST-HSCs ratio and fold expansion of the 5 mmol/L NAM group were significantly higher than those of the control and 10 mmol/L NAM groups(all P<0.001),whereas the LT-HSCs ratio and fold expansion of the 10 mmol/L NAM group were significantly higher than those of the other two groups(all P<0.05).When the NAM concentration was>10 mmol/L,cell viability significantly decreased.In addition,compared with the 5 mmol/L NAM group,the proportion of apoptotic cells in the 10 mmol/L NAM group increased and the proportion of cells in S and G2 phase decreased.Compared with the 5 mmol/L NAM group,the HSCs incubated with 10 mmol/L NAM exhibited significantly inhibited SIRT1 expression,increased intracellular ROS content,and downregulated expression of genes encoding antioxidant enzymes(superoxide dismutase 1,peroxiredoxin 1).CONCLUSION Low concentrations(5 mmol/L)of NAM can better regulate the balance between proliferation and differentiation,thereby promoting expansion of HSCs.These findings allow adjustment of NAM concentrations according to expansion needs.

Reveal more mechanisms of precondition mesenchymal stem cells inhibiting inflammation

Hypoxia can get more ability to inhibit inflammation.But how it impact on survival time of mesenchymal stem cells(MSCs)is confusing and how preconditioned MSCs inhibiting inflammation are partially known.Those issues decided the value of preconditioned MSCs by hypoxia.