The loss-of-function mutations in the ALPL result in hypophosphatasia(HPP), an inborn metabolic disorder that causes skeletal mineralization defects. In adults, the main clinical features are early loss of primary or ...The loss-of-function mutations in the ALPL result in hypophosphatasia(HPP), an inborn metabolic disorder that causes skeletal mineralization defects. In adults, the main clinical features are early loss of primary or secondary teeth, osteoporosis, bone pain,chondrocalcinosis, and fractures. However, guidelines for the treatment of adults with HPP are not available. Here, we show that ALPL deficiency caused a reduction in intracellular Ca2+ influx, resulting in an osteoporotic phenotype due to downregulated osteogenic differentiation and upregulated adipogenic differentiation in both human and mouse bone marrow mesenchymal stem cells(BMSCs). Increasing the intracellular level of calcium in BMSCs by ionomycin treatment rescued the osteoporotic phenotype in alpl+/- mice and BMSC-specific(Prrx1-alpl-/-) conditional alpl knockout mice. Mechanistically, ALPL was found to be required for the maintenance of intracellular Ca2+ influx, which it achieves by regulating L-type Ca2+ channel trafficking via binding to the α2δsubunits to regulate the internalization of the L-type Ca2+ channel. Decreased Ca2+ flux inactivates the Akt/GSK3β/β-catenin signaling pathway, which regulates lineage differentiation of BMSCs. This study identifies a previously unknown role of the ectoenzyme ALPL in the maintenance of calcium channel trafficking to regulate stem cell lineage differentiation and bone homeostasis. Accelerating Ca2+ flux through L-type Ca2+ channels by ionomycin treatment may be a promising therapeutic approach for adult patients with HPP.展开更多
Choline phosphate （CP） as a novel zwitterion possesses specific and excellent properties compared with phosphorylcholine （PC）, as well as its polymer, such as poly（2-（methacryloyloxy）ethyl choline phosphate） ...Choline phosphate （CP） as a novel zwitterion possesses specific and excellent properties compared with phosphorylcholine （PC）, as well as its polymer, such as poly（2-（methacryloyloxy）ethyl choline phosphate） （PMCP）, has been studied extensively due to its unique characteristics of rapid cellular internalization via the special quadrupole interactions with the cell membrane. Recently, we reported a novel PMCP-based drug delivery system to enhance the cellular internalization where the drug was conjugated to the polymer via reversible acylhydrazone bond. Herein, to make full use of this feature of PMCP, we synthesized the diblock copolymer poly（2-（methacryloyloxy）ethyl choline phosphate）-b-poly（2- （diisopropylamino）ethyl methacrylate） （PMCP-b-PDPA）, which could self-assemble into polymersomes with hydrophilic PMCP corona and hydrophobic membrane wall in mild conditions when the pH value is 〉 6.4. It has been found that these polymersomes can be successfully used to load anticancer drug Dox with the loading content of about 11.30 wt%. After the polymersome is rapidly internalized by the cell with the aid of PMCP, the loaded drug can be burst-released in endosomes since PDPA segment is protonated at low pH environment, which renders PDPA to transfer from hydrophobic to hydrophilic, and the subsequent polymersomes collapse thoroughly. Ultimately, the ＂proton sponge＂ effect of PDPA chain can further accelerate the Dox to escape from endosome to cytoplasm to exert cytostatic effects. Meanwhile, the cell viability assays showed that the Dox-loaded polymersomes exhibited significant inhibitory effect on tumor cells, indicating its great potential as a targeted intracellular delivery system with high efficiency.展开更多
To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced...To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced by cecal ligation and puncture (CLP). ET1 receptor was assayed by using [125I]- ET1 binding. Marker enzyme activities, protein yield, and dry- to- wet weight ratio of cardiac membranes were measured. Results. Septic rat heart exhibited two distinct phases: an initial hyperdynamic phase( 9h after CLP; early stage of sepsis) followed by a hypodynamic (18h after CLP, late stage of sepsis) phase. [125I]- ET1 binding study showed that during early stage of sepsis, the Bmax of ET1 receptors was increased by 30％ in sarcolemma but decreased by 19％ in light vesicles, while during late stage of sepsis, the Bmax was decreased by 24％ in sarcolemma but increased by 38％ in light vesicles.The total binding of sarcolemma and light vesicles was increased by 25％ during early stage of sepsis but decreased by 17％ during late stage of sepsis. Conclusions. These data indicated that ET1 receptors in the rat heart were externalized from light vesicles to sarcolemmal membranes during early hyperdynamic phase while internalized from surface membranes to intracellular compartment during late hypodynamic phase of sepsis.展开更多
Guanidinylated bioresponsive poly(amido amine)s polymers, CAR-CBA and CHL-CBA, weresynthesized by Michael-type addition reaction between guanidine hydrochloride(CAR) orchlorhexidine(CHL) and N,N-cystaminebisacrylamide...Guanidinylated bioresponsive poly(amido amine)s polymers, CAR-CBA and CHL-CBA, weresynthesized by Michael-type addition reaction between guanidine hydrochloride(CAR) orchlorhexidine(CHL) and N,N-cystaminebisacrylamide(CBA). Previous studies have shownthat both polymers had high transfection efficiencies as gene delivery carriers. In this study,we investigated the nucleolus localization abilities and cellular internalization pathways ofthese two polymers in gene delivery. Each polymer condensed plasmid DNA(p DNA) andformed nanoparticle complexes, and then their transfection studies were performed inMCF-7 cells. Both complexes were found enriched in nucleolus after cellular transfection,and their transfection efficiencies were significantly improved when transfection was per-formed on MCF-7 cells arrested at M phase. The transfection efficiency of CAR-CBA-pDNAwas inhibited by chlorpromazine, and cell endosomes were disrupted after being exposedto CAR-CBA-pDNA. In regards to CHL-CBA-pDNA, its transfection efficiency was not affected by three types of endocytosis inhibitors used in the study, and CHL-CBA-pDNA showed no effect on endosomes. Cellular lactate dehydrogenase release and membrane morphology were changed after cells were transfected by the two complexes. The results indicated that both CAR-CBA and CHL-CBA polymers demonstrated good nucleolus localization abilities. It was beneficial for transfection when cells were arrested at M phase. CAR-CBA-pDNA cellular internalization was involved with clathrin-mediated endocytosis pathway, and escaping from endosomal entrapment, while the cellular uptake of CHL-CBA-pDNA occurs via clathrin-and caveolae-independent mechanism.展开更多
Neuropathic pain is of serious clinical concern and only about half of patients achieve partial relief with currently-available treatments,so it is critical to find new drugs for this condition.Recently,the cellsurfac...Neuropathic pain is of serious clinical concern and only about half of patients achieve partial relief with currently-available treatments,so it is critical to find new drugs for this condition.Recently,the cellsurface trafficking of pain-related receptors has been suggested as an important mechanism underlying persistent neuropathic pain.Here,we used the short peptide GluA_（2-3y）,which specifically inhibits the GluA2-dependent endocytosis of a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors,and tested its anti-nociceptive effect in the periaqueductal grey（PAG） of intact rats and rats with neuropathic pain.Intra-PAG injection of 0.15,1.5,7.5,and 15 pmol of GluA_（2-3y） induced dose-dependent increases in hindpaw withdrawal latencies to noxious thermal and mechanical stimuli in intact rats,suggesting that GluA2 cell-surface trafficking in the PAG is involved in pain modulation.Furthermore,GluA_（2-3y） had much stronger anti-nociceptive effects in rats with neuropathic pain induced by sciatic nerve ligation.Interestingly,the intra-PAG injection of 15 pmol GluA_（2-3y） had an analgesic effect similar to 10 ug（35nmol） morphine in rats with neuropathic pain.Taken together,our results suggested that GluA2 trafficking in the PAG plays a critical role in pain modulation,and inhibiting GluA2 endocytosis with GluA_（2-3y） has potent analgesic effects in rats with neuropathic pain.These findings strongly support the recent hypothesis that targeting receptor trafficking could be a new strategy for the treatment of neuropathic pain.展开更多
In order to study the fate of human follicle-stimulating hormone (FSH) when hormone binds to its receptor, a quick biochemical method that can differentiate between the surface-bound and internalized hormone was used ...In order to study the fate of human follicle-stimulating hormone (FSH) when hormone binds to its receptor, a quick biochemical method that can differentiate between the surface-bound and internalized hormone was used to determine the internalization induced by FSH in cultured both porcine granulosa cells and Chinese hamster ovary (CHO) cells expressing recombinant porcine FSH receptor. The results showed that FSH was slowly internalized, and the internalized radioactivity (acid resistant) reached a peak 10-12 h after addition of 125 I-hFSH. It was suggested that FSHR do not get internalized rapidly under physiological circumstances precisely because the appropriate sequences are absent.展开更多
Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets an...Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets and activates mitochondria,presenting an important molecular mechanism.However,its regulating signaling pathways remain to be elucidated.We investigated the influence of specific inhibitors of G protein-coupled receptors(GPCR),endocytosis pathways,extracellular signal-regulated kinases1/2(ERK1/2)signaling,p38 signaling,mitochondrial respiration and Na+/K+-ATPase activity on the uptake,mitochondria-targeting and-activating properties of F-Hst1.We performed a si RNA knockdown(KD)to assess the effect of Sigma-2 receptor(S2R)/Transmembrane Protein 97(TMEM97)—a recently identified target protein of Hst1.We also adopted live cell imaging to monitor the whole intracellular trafficking process of F-Hst1.Our results showed that the inhibition of cellular respiration hindered the internalization of F-Hst1.The inhibitors of GPCR,ERK1/2,phagocytosis,and clathrin-mediated endocytosis(CME)as well as siRNA KD of S2R/TMEM97 significantly reduced the uptake,which was accompanied by the nullification of the promoting effect of F-Hst1 on cell metabolic activity.Only the inhibitor of CME and KD of S2R/TMEM97 significantly compromised the mitochondria-targeting of Hst1.We further showed the intracellular trafficking and targeting process of F-Hst1,in which early endosome plays an important role.Overall,phagocytosis,CME,GPCR,ERK signaling,and S2R/TMEM97 are involved in the internalization of Hst1,while only CME and S2R/TMEM97 are critical for its subcellular targeting.The inhibition of either internalization or mitochondria-targeting of Hst1 could significantly compromise its mitochondria-activating property.展开更多
Exposure to media that portrays thin women as ideal and attractive can lead to women internalizing the thin ideal, which results in incorporating societal standards of thinness into belief systems. Internalization of ...Exposure to media that portrays thin women as ideal and attractive can lead to women internalizing the thin ideal, which results in incorporating societal standards of thinness into belief systems. Internalization of the thin-ideal is associated with numerous detrimental effects on women, including decreased levels of self-esteem and increased levels of body-focused anxiety, negative emotions and disordered eating. The present study utilized a sample of women (N = 208) aged between 18 and 67 years (M = 29.44, SD = 13.08) to examine the relationship between internalization of the thin- ideal, body-focused anxiety, body mass index (BMI), and dieting frequency. Correlational, regression and mediation analyses conducted on the data showed that internalization of the thin-ideal, BMI and dieting frequency significantly contributed to body-focused anxiety in women. In addition, body-focused anxiety fully mediated the relationship between internalization of the thin-ideal and dieting frequency among women. BMI did not moderate the relationship between internalization of the thin-ideal and body-focused, indicating that women who internalize the thin-ideal are less vulnerable to dieting unless experiencing body-focused anxiety. The results of the current study enhance our understanding of the relationship between internalization of the thin-ideal, body-focused anxiety, BMI, and dieting frequency among women. Clinical implications will be discussed.展开更多
This research focused on ＂half-a-day＂ as a mode of internalizing vocational and technical education by the youths in Nigeria. It traced the origin of ＂half-a-day＂ linking it with the ingenuity of the youths to mak...This research focused on ＂half-a-day＂ as a mode of internalizing vocational and technical education by the youths in Nigeria. It traced the origin of ＂half-a-day＂ linking it with the ingenuity of the youths to make the formal education that they have acquired operational. It also discussed the traditional education with its apprenticeship system as being modified through the ＂half-a-day＂ syndrome. The study is historical and descriptive therefore, social survey method was employed using unscheduled interview and consulting relevant literature. It was discovered that, apart from the failure of the educational system due to lack of proper infrastructure, the youths, especially those from the lower class, have reasoned that the salaries from the white-collar jobs may not be enough to sustain them. It is, therefore, recommended, among others, that： Government can institutionalise the ＂half-a-day＂ as a form of summer school and certify both the centres of learning and learners.展开更多
Follicle stimulating hormone (FSH) is a kind of glycoprotein gonadotropin, and plays an important role in the diagnosis and treatment of infertility. Follicle stimulating hormone receptor (FSHR) is a kind of G protein...Follicle stimulating hormone (FSH) is a kind of glycoprotein gonadotropin, and plays an important role in the diagnosis and treatment of infertility. Follicle stimulating hormone receptor (FSHR) is a kind of G protein coupled receptor (GPCR), found in the ovary and testes, and its activation is required for the hormonal operation during the breeding period. In this study, an experimental model of FSHR mediated FSH into cell membrane, which exhibited a phenomenon of fluorescent localized on cell surfaces internalized into cell interior, was established to verify biological activity of FSH.展开更多
In the era of the globalization of the economy, the network of the information, and the socialization of the citizens, there is the tendency that a country＇s domestic problems will be internationalized, while the int...In the era of the globalization of the economy, the network of the information, and the socialization of the citizens, there is the tendency that a country＇s domestic problems will be internationalized, while the international issues will be domestic. Combined with the background of China to realize the ＂China Dreams＂, in the field of the public diplomacy, we should pay sufficient attention to the ＂internalization＂ construction in the aspects of the value ideas, the mode of the systems, the political propositions, and the cultural influence and so on, which is the benign interaction involving the governments, the citizens and the social organizations. In this paper, the author casts a brick to attract jade. Through the discussion of the necessity of the ＂internalization＂ construction of the public diplomacy, the author carries out the discussion from the social and the cultural dimensions, in order to arouse the attention to the ＂internalization＂ construction of the public diplomacy, so that our country will be more influential in the politics, and more approachable in the images, and more appealing in the morality.展开更多
Along with the quick development of social economy, market competition has already entered into a new stage, namely brand competition era. This paper is to put forward scientifically rational countermeasures and sugge...Along with the quick development of social economy, market competition has already entered into a new stage, namely brand competition era. This paper is to put forward scientifically rational countermeasures and suggestions through taking brand internalization theory as basis and starting from regional industry competitiveness. Thus it would increase regional industry competitiveness of brand.展开更多
Flipped classroom model led to the transformation of university teachers＇ teaching role. From the perspective of the sociology of knowledge, the teacher professional development is a process of transformation of the ...Flipped classroom model led to the transformation of university teachers＇ teaching role. From the perspective of the sociology of knowledge, the teacher professional development is a process of transformation of the role of teachers, and role transformation and the way of actors involved in the knowledge are associated. Participating in knowledge in different ways, role types are also different. Thus, changing the way ofparticipating in knowledge is the basic way to participate in the transformation of the role. Classification of roles is not the classification ofhumans.A social may might play many roles of many types in his life andmay have the function of a variety of roles at the same time. Meanwhile, it can be transferred between characters, especially in the case of depending on the same knowledge system.As long as the ways of involvement are different,the functions and types of roles are also different. University teachers are those who play a variety of roles of knowledge and society, some being the teaching teachers of organization and dissemination of knowledge, some being scientific and teaching teachers who focus on organizing and disseminating knowledge as well as knowledge creation, and knowledge creation and heavy teacher teaching and research, while others are knowledge creation based research teachers. In the field of the sociology of knowledge, university teachers should be scientific teaching roles depending on a deep knowledge and participating in knowledge in a variety of ways. From the perspective of the sociology of knowledge, according to Eph · Znaniecki＇ s role classification, university teachers participate in knowledge in three ways： teaching, learning and researching. Teaching, learning and researching are relative but different ways of participating in knowledge. State they are relative because itshows teaching can promote learning, learning can promote researching, researching can also promote learning and teaching. The homochromous interaction of teaching, leaming and researching, knowledge is in constant state of development and generation.展开更多
Background To study the molecular mechanisms of CREG(the cellular repressor of E1A-stimulated gene) on proliferation of VSMCs in vitro.Methods The pRc/CMV-CREG plasmid or the pSM2-siCREG plasmid was transferred into h...Background To study the molecular mechanisms of CREG(the cellular repressor of E1A-stimulated gene) on proliferation of VSMCs in vitro.Methods The pRc/CMV-CREG plasmid or the pSM2-siCREG plasmid was transferred into human vascular smooth muscle cells(hVSMCs) to produce the cell clone that over-expression or down-expression of CREG respectively.BrdU assay and FACS cell cycle analysis were used to detect the proliferation of cells.Western blotting and immunocytochemistry show the expression and localization of IGF2R in hVSMCs.RT-PCR and ELISA assay determined the expression and secretion of IGFII factor. Alex488-labeled rhIGFII was used to investigate the endocysis of cells.And the blockade of IGFII internalization by treatment both the neutralized antibody of anti-IGF2R and rsIGF2R detected the effect of IGFII on VSMCs growth. Furthermore,Western blotting and signal pathway inhibitor were used to analysis the activation of PI3K/AKT and ERK on VSMCs proliferation.Results Western blotting identified that the expression of CREG in hVSMCs-CREG cells increased compared to control cell,and the decreased obviously in hVSMCs-siCREG cells.Meanwhile,the overexpression of CREG in cells was detected to inhibit the proliferation of VSMCs and to enhance the distribution of IGF2R in cellular membrane.Furthermore,overexpression of CREG also accelerated the endocysis of IGFII in hVSMCs-CREG,and attenuate the secretion of IGFII into cell medium by ELISA analysis and Alex488 labeled IGFII analysis.Blockade experiments both neutralized antibody of IGF2R and rhIGF2R fragment determined that enhancement of IGFII secretion promoted the VSMCs proliferation,and PI3K/AKT and ERK signal pathway mediated the effect of IGFII on VSMCs.Conclusions Altogether, these data indicate that CREG inhibits the proliferation of hVSMCs through interfering into the internalization pathway of IGF2R-IGFII.展开更多
On the basis of clarifying the teachers'Ethics internalization theory,this paper analyzes the typical dilemma in teachers'Ethics internalization.To resolve these problems,this paper construct an overall framew...On the basis of clarifying the teachers'Ethics internalization theory,this paper analyzes the typical dilemma in teachers'Ethics internalization.To resolve these problems,this paper construct an overall framework,including security mechanism,normative mechanism,education mechanism,evaluation mechanism and supervision mechanism,which the external conditions are used to constantly strengthen the moral needs of the subject,then enhance the consciousness of moral internalization,improve the effectiveness of teachers'moral construction.展开更多
In the Research Article “Tumor Microenvironment-Specific Chemical Internalization for Enhanced Gene Therapy of Metastatic Breast Cancer,” the authors made an error in Fig. 6A. In Fig. 6A, the image of “pre” in the...In the Research Article “Tumor Microenvironment-Specific Chemical Internalization for Enhanced Gene Therapy of Metastatic Breast Cancer,” the authors made an error in Fig. 6A. In Fig. 6A, the image of “pre” in the “Free Cy5-siRNA” group was misused. When incorporating the final images in Fig. 6A, another image of “24 h” in the “Free Cy5-siRNA” group was inadvertently chosen as the “Pre” image, so they appear to be remarkably similar. After the error was discovered, the authors repeated the experiments that concluded that this error did not affect the results, discussion, or conclusion of this paper. Figure 6A has now been corrected in the PDF and HTML (full text).展开更多
Photo-Cross-Linkable hydrogel has attracted immense interest in the regeneration of bone repair and regeneration strategies due to its superior biocompatibility and tunable mechanical properties.Recently,Nb was report...Photo-Cross-Linkable hydrogel has attracted immense interest in the regeneration of bone repair and regeneration strategies due to its superior biocompatibility and tunable mechanical properties.Recently,Nb was reported to strongly promote the bone regeneration process via an accelerated osteoblast-modulated alkaline phosphatase activity mechanism.In particular,Nb2C MXenes have drawn widespread attention due to their excellent biocompatibility and ability to induce bone formation.However,the easy agglomeration of Nb2C nanosheets and subsequent low cell endocytosis efficacy greatly suppressed the osteogenesis effect.In this study,a subtractive nanopore-engineered Nb2C MXene was prepared through a microwave combustion method,gelatin methacrylate was used as the carrier hydrogel,and the photo-triggered Porous-Nb2C@GelMA hydrogel was fabricated by a photo-triggered process.The pore-forming strategy not only successfully improved the distribution of Nb2C and formed more homogenous Porous-Nb2C@GelMA hydrogels but also guided bone marrow mesenchymal stem cells(BMSCs)toward osteoblast differentiation.Porous Nb2C provided convenient cellular grasping and endocytosis for BMSCs,which further created a favorable environment for differentiation and osteogenesis.This,in turn,leads to an increase in the expression of osteogenic markers,such as ALP and ARS,as well as osteogenic factors,such as BMP-2,COL-1,OCN,and OPN.Consequently,enhancing the regenerative microenvironment by incorporating porous Nb2C composite hydrogels shows promise for application in bone regeneration.展开更多
Salmonella enterica serovar Typhimurium,the causative agent of gastroenteritis,is one of the most successful intracellular pathogens.Although certain host factors for Salmonella infection have been unveiled,the factor...Salmonella enterica serovar Typhimurium,the causative agent of gastroenteritis,is one of the most successful intracellular pathogens.Although certain host factors for Salmonella infection have been unveiled,the factors mediating Salmonella entry,particularly the invasion process,remain obscure.Here,we have unearthed β2 integrin,a crucial member of the integrin family,as an important host factor facilitating Salmonella invasion.It is demonstrated that overexpression of β2 integrin promotes Salmonella invasion,while the knockdown of β2 integrin significantly diminishes the extent of invasion.Moreover,Salmonella exhibits specific binding affinity towards β2 integrin,and the block of β2 integrin on cell surface substantially reduces the infection of cells in vitro.The ectodomain soluble protein of β2 integrin neutralized Salmonella infection both in cells(in vitro)and in mice(in vivo).Additionally,Salmonella protein YrbD directly interacts with β2 integrin to facilitate its invasion.To our knowledge,this study showed for the first time that the protein YrbD mediates Salmonella adhesion and internalization into host cells by interacting with β2 integrin.These findings not only broaden our understanding of the mechanisms underlying Salmonella entry,but also identify a prospective target for therapeutic control.展开更多
α-Synuclein accumulation and transmission are vital to the pathogenesis of Parkinson's disease,although the mechanisms underlying misfoldedα-synuclein accumulation and propagation have not been conclusively dete...α-Synuclein accumulation and transmission are vital to the pathogenesis of Parkinson's disease,although the mechanisms underlying misfoldedα-synuclein accumulation and propagation have not been conclusively determined.The expression of low-density lipoprotein receptor–related protein 1,which is abundantly expressed in neurons and considered to be a multifunctional endocytic receptor,is elevated in the neurons of patients with Parkinson's disease.However,whether there is a direct link between low-density lipoprotein receptor–related protein 1 andα-synuclein aggregation and propagation in Parkinson's disease remains unclear.Here,we established animal models of Parkinson's disease by inoculating monkeys and mice withα-synuclein pre-formed fibrils and observed elevated low-density lipoprotein receptor–related protein 1 levels in the striatum and substantia nigra,accompanied by dopaminergic neuron loss and increasedα-synuclein levels.However,low-density lipoprotein receptor–related protein 1 knockdown efficiently rescued dopaminergic neurodegeneration and inhibited the increase inα-synuclein levels in the nigrostriatal system.In HEK293A cells overexpressingα-synuclein fragments,low-density lipoprotein receptor–related protein 1 levels were upregulated only when the N-terminus ofα-synuclein was present,whereas anα-synuclein fragment lacking the N-terminus did not lead to low-density lipoprotein receptor–related protein 1 upregulation.Furthermore,the N-terminus ofα-synuclein was found to be rich in lysine residues,and blocking lysine residues in PC12 cells treated withα-synuclein pre-formed fibrils effectively reduced the elevated low-density lipoprotein receptor–related protein 1 andα-synuclein levels.These findings indicate that low-density lipoprotein receptor–related protein 1 regulates pathological transmission ofα-synuclein from the striatum to the substantia nigra in the nigrostriatal system via lysine residues in theα-synuclein N-terminus.展开更多
基金funded by grants from the National Natural Science Foundation of China (Nos. 81620108007 and 81870768)the National Key Research and Development Program of China (Nos. 2016YFC1101400 and 2017YFA0104800)the Scientific Young Alma of Shaanxi province (2018KJXX-015)。
文摘The loss-of-function mutations in the ALPL result in hypophosphatasia(HPP), an inborn metabolic disorder that causes skeletal mineralization defects. In adults, the main clinical features are early loss of primary or secondary teeth, osteoporosis, bone pain,chondrocalcinosis, and fractures. However, guidelines for the treatment of adults with HPP are not available. Here, we show that ALPL deficiency caused a reduction in intracellular Ca2+ influx, resulting in an osteoporotic phenotype due to downregulated osteogenic differentiation and upregulated adipogenic differentiation in both human and mouse bone marrow mesenchymal stem cells(BMSCs). Increasing the intracellular level of calcium in BMSCs by ionomycin treatment rescued the osteoporotic phenotype in alpl+/- mice and BMSC-specific(Prrx1-alpl-/-) conditional alpl knockout mice. Mechanistically, ALPL was found to be required for the maintenance of intracellular Ca2+ influx, which it achieves by regulating L-type Ca2+ channel trafficking via binding to the α2δsubunits to regulate the internalization of the L-type Ca2+ channel. Decreased Ca2+ flux inactivates the Akt/GSK3β/β-catenin signaling pathway, which regulates lineage differentiation of BMSCs. This study identifies a previously unknown role of the ectoenzyme ALPL in the maintenance of calcium channel trafficking to regulate stem cell lineage differentiation and bone homeostasis. Accelerating Ca2+ flux through L-type Ca2+ channels by ionomycin treatment may be a promising therapeutic approach for adult patients with HPP.
基金financially supported by the National Natural Science Foundation of China(Nos.21304096,21474103,21603214 and 21674109)
文摘Choline phosphate （CP） as a novel zwitterion possesses specific and excellent properties compared with phosphorylcholine （PC）, as well as its polymer, such as poly（2-（methacryloyloxy）ethyl choline phosphate） （PMCP）, has been studied extensively due to its unique characteristics of rapid cellular internalization via the special quadrupole interactions with the cell membrane. Recently, we reported a novel PMCP-based drug delivery system to enhance the cellular internalization where the drug was conjugated to the polymer via reversible acylhydrazone bond. Herein, to make full use of this feature of PMCP, we synthesized the diblock copolymer poly（2-（methacryloyloxy）ethyl choline phosphate）-b-poly（2- （diisopropylamino）ethyl methacrylate） （PMCP-b-PDPA）, which could self-assemble into polymersomes with hydrophilic PMCP corona and hydrophobic membrane wall in mild conditions when the pH value is 〉 6.4. It has been found that these polymersomes can be successfully used to load anticancer drug Dox with the loading content of about 11.30 wt%. After the polymersome is rapidly internalized by the cell with the aid of PMCP, the loaded drug can be burst-released in endosomes since PDPA segment is protonated at low pH environment, which renders PDPA to transfer from hydrophobic to hydrophilic, and the subsequent polymersomes collapse thoroughly. Ultimately, the ＂proton sponge＂ effect of PDPA chain can further accelerate the Dox to escape from endosome to cytoplasm to exert cytostatic effects. Meanwhile, the cell viability assays showed that the Dox-loaded polymersomes exhibited significant inhibitory effect on tumor cells, indicating its great potential as a targeted intracellular delivery system with high efficiency.
基金This study was supported by the National Nature Scientific Fund (No.39730220).
文摘To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced by cecal ligation and puncture (CLP). ET1 receptor was assayed by using [125I]- ET1 binding. Marker enzyme activities, protein yield, and dry- to- wet weight ratio of cardiac membranes were measured. Results. Septic rat heart exhibited two distinct phases: an initial hyperdynamic phase( 9h after CLP; early stage of sepsis) followed by a hypodynamic (18h after CLP, late stage of sepsis) phase. [125I]- ET1 binding study showed that during early stage of sepsis, the Bmax of ET1 receptors was increased by 30％ in sarcolemma but decreased by 19％ in light vesicles, while during late stage of sepsis, the Bmax was decreased by 24％ in sarcolemma but increased by 38％ in light vesicles.The total binding of sarcolemma and light vesicles was increased by 25％ during early stage of sepsis but decreased by 17％ during late stage of sepsis. Conclusions. These data indicated that ET1 receptors in the rat heart were externalized from light vesicles to sarcolemmal membranes during early hyperdynamic phase while internalized from surface membranes to intracellular compartment during late hypodynamic phase of sepsis.
基金supported by National Natural Science Foundation of China (Grant no. 81373335)
文摘Guanidinylated bioresponsive poly(amido amine)s polymers, CAR-CBA and CHL-CBA, weresynthesized by Michael-type addition reaction between guanidine hydrochloride(CAR) orchlorhexidine(CHL) and N,N-cystaminebisacrylamide(CBA). Previous studies have shownthat both polymers had high transfection efficiencies as gene delivery carriers. In this study,we investigated the nucleolus localization abilities and cellular internalization pathways ofthese two polymers in gene delivery. Each polymer condensed plasmid DNA(p DNA) andformed nanoparticle complexes, and then their transfection studies were performed inMCF-7 cells. Both complexes were found enriched in nucleolus after cellular transfection,and their transfection efficiencies were significantly improved when transfection was per-formed on MCF-7 cells arrested at M phase. The transfection efficiency of CAR-CBA-pDNAwas inhibited by chlorpromazine, and cell endosomes were disrupted after being exposedto CAR-CBA-pDNA. In regards to CHL-CBA-pDNA, its transfection efficiency was not affected by three types of endocytosis inhibitors used in the study, and CHL-CBA-pDNA showed no effect on endosomes. Cellular lactate dehydrogenase release and membrane morphology were changed after cells were transfected by the two complexes. The results indicated that both CAR-CBA and CHL-CBA polymers demonstrated good nucleolus localization abilities. It was beneficial for transfection when cells were arrested at M phase. CAR-CBA-pDNA cellular internalization was involved with clathrin-mediated endocytosis pathway, and escaping from endosomal entrapment, while the cellular uptake of CHL-CBA-pDNA occurs via clathrin-and caveolae-independent mechanism.
基金supported by the National Natural Science Foundation of China (30670658)support from the Minzu University 985 Academic Team-building Fund (YLDX01013, 2015MDTD13C and 25C)the 111 Project of China (B08044)
文摘Neuropathic pain is of serious clinical concern and only about half of patients achieve partial relief with currently-available treatments,so it is critical to find new drugs for this condition.Recently,the cellsurface trafficking of pain-related receptors has been suggested as an important mechanism underlying persistent neuropathic pain.Here,we used the short peptide GluA_（2-3y）,which specifically inhibits the GluA2-dependent endocytosis of a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors,and tested its anti-nociceptive effect in the periaqueductal grey（PAG） of intact rats and rats with neuropathic pain.Intra-PAG injection of 0.15,1.5,7.5,and 15 pmol of GluA_（2-3y） induced dose-dependent increases in hindpaw withdrawal latencies to noxious thermal and mechanical stimuli in intact rats,suggesting that GluA2 cell-surface trafficking in the PAG is involved in pain modulation.Furthermore,GluA_（2-3y） had much stronger anti-nociceptive effects in rats with neuropathic pain induced by sciatic nerve ligation.Interestingly,the intra-PAG injection of 15 pmol GluA_（2-3y） had an analgesic effect similar to 10 ug（35nmol） morphine in rats with neuropathic pain.Taken together,our results suggested that GluA2 trafficking in the PAG plays a critical role in pain modulation,and inhibiting GluA2 endocytosis with GluA_（2-3y） has potent analgesic effects in rats with neuropathic pain.These findings strongly support the recent hypothesis that targeting receptor trafficking could be a new strategy for the treatment of neuropathic pain.
基金This project was supported by a grant from Hubei Provincial Natural Sciences Foundation (No. 99J15 8) and HubeiScience and Technology Departm ent Foundation
文摘In order to study the fate of human follicle-stimulating hormone (FSH) when hormone binds to its receptor, a quick biochemical method that can differentiate between the surface-bound and internalized hormone was used to determine the internalization induced by FSH in cultured both porcine granulosa cells and Chinese hamster ovary (CHO) cells expressing recombinant porcine FSH receptor. The results showed that FSH was slowly internalized, and the internalized radioactivity (acid resistant) reached a peak 10-12 h after addition of 125 I-hFSH. It was suggested that FSHR do not get internalized rapidly under physiological circumstances precisely because the appropriate sequences are absent.
基金funded by Eurostars project,grant number E!12764。
文摘Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets and activates mitochondria,presenting an important molecular mechanism.However,its regulating signaling pathways remain to be elucidated.We investigated the influence of specific inhibitors of G protein-coupled receptors(GPCR),endocytosis pathways,extracellular signal-regulated kinases1/2(ERK1/2)signaling,p38 signaling,mitochondrial respiration and Na+/K+-ATPase activity on the uptake,mitochondria-targeting and-activating properties of F-Hst1.We performed a si RNA knockdown(KD)to assess the effect of Sigma-2 receptor(S2R)/Transmembrane Protein 97(TMEM97)—a recently identified target protein of Hst1.We also adopted live cell imaging to monitor the whole intracellular trafficking process of F-Hst1.Our results showed that the inhibition of cellular respiration hindered the internalization of F-Hst1.The inhibitors of GPCR,ERK1/2,phagocytosis,and clathrin-mediated endocytosis(CME)as well as siRNA KD of S2R/TMEM97 significantly reduced the uptake,which was accompanied by the nullification of the promoting effect of F-Hst1 on cell metabolic activity.Only the inhibitor of CME and KD of S2R/TMEM97 significantly compromised the mitochondria-targeting of Hst1.We further showed the intracellular trafficking and targeting process of F-Hst1,in which early endosome plays an important role.Overall,phagocytosis,CME,GPCR,ERK signaling,and S2R/TMEM97 are involved in the internalization of Hst1,while only CME and S2R/TMEM97 are critical for its subcellular targeting.The inhibition of either internalization or mitochondria-targeting of Hst1 could significantly compromise its mitochondria-activating property.
文摘Exposure to media that portrays thin women as ideal and attractive can lead to women internalizing the thin ideal, which results in incorporating societal standards of thinness into belief systems. Internalization of the thin-ideal is associated with numerous detrimental effects on women, including decreased levels of self-esteem and increased levels of body-focused anxiety, negative emotions and disordered eating. The present study utilized a sample of women (N = 208) aged between 18 and 67 years (M = 29.44, SD = 13.08) to examine the relationship between internalization of the thin- ideal, body-focused anxiety, body mass index (BMI), and dieting frequency. Correlational, regression and mediation analyses conducted on the data showed that internalization of the thin-ideal, BMI and dieting frequency significantly contributed to body-focused anxiety in women. In addition, body-focused anxiety fully mediated the relationship between internalization of the thin-ideal and dieting frequency among women. BMI did not moderate the relationship between internalization of the thin-ideal and body-focused, indicating that women who internalize the thin-ideal are less vulnerable to dieting unless experiencing body-focused anxiety. The results of the current study enhance our understanding of the relationship between internalization of the thin-ideal, body-focused anxiety, BMI, and dieting frequency among women. Clinical implications will be discussed.
文摘This research focused on ＂half-a-day＂ as a mode of internalizing vocational and technical education by the youths in Nigeria. It traced the origin of ＂half-a-day＂ linking it with the ingenuity of the youths to make the formal education that they have acquired operational. It also discussed the traditional education with its apprenticeship system as being modified through the ＂half-a-day＂ syndrome. The study is historical and descriptive therefore, social survey method was employed using unscheduled interview and consulting relevant literature. It was discovered that, apart from the failure of the educational system due to lack of proper infrastructure, the youths, especially those from the lower class, have reasoned that the salaries from the white-collar jobs may not be enough to sustain them. It is, therefore, recommended, among others, that： Government can institutionalise the ＂half-a-day＂ as a form of summer school and certify both the centres of learning and learners.
文摘Follicle stimulating hormone (FSH) is a kind of glycoprotein gonadotropin, and plays an important role in the diagnosis and treatment of infertility. Follicle stimulating hormone receptor (FSHR) is a kind of G protein coupled receptor (GPCR), found in the ovary and testes, and its activation is required for the hormonal operation during the breeding period. In this study, an experimental model of FSHR mediated FSH into cell membrane, which exhibited a phenomenon of fluorescent localized on cell surfaces internalized into cell interior, was established to verify biological activity of FSH.
文摘In the era of the globalization of the economy, the network of the information, and the socialization of the citizens, there is the tendency that a country＇s domestic problems will be internationalized, while the international issues will be domestic. Combined with the background of China to realize the ＂China Dreams＂, in the field of the public diplomacy, we should pay sufficient attention to the ＂internalization＂ construction in the aspects of the value ideas, the mode of the systems, the political propositions, and the cultural influence and so on, which is the benign interaction involving the governments, the citizens and the social organizations. In this paper, the author casts a brick to attract jade. Through the discussion of the necessity of the ＂internalization＂ construction of the public diplomacy, the author carries out the discussion from the social and the cultural dimensions, in order to arouse the attention to the ＂internalization＂ construction of the public diplomacy, so that our country will be more influential in the politics, and more approachable in the images, and more appealing in the morality.
文摘Along with the quick development of social economy, market competition has already entered into a new stage, namely brand competition era. This paper is to put forward scientifically rational countermeasures and suggestions through taking brand internalization theory as basis and starting from regional industry competitiveness. Thus it would increase regional industry competitiveness of brand.
文摘Flipped classroom model led to the transformation of university teachers＇ teaching role. From the perspective of the sociology of knowledge, the teacher professional development is a process of transformation of the role of teachers, and role transformation and the way of actors involved in the knowledge are associated. Participating in knowledge in different ways, role types are also different. Thus, changing the way ofparticipating in knowledge is the basic way to participate in the transformation of the role. Classification of roles is not the classification ofhumans.A social may might play many roles of many types in his life andmay have the function of a variety of roles at the same time. Meanwhile, it can be transferred between characters, especially in the case of depending on the same knowledge system.As long as the ways of involvement are different,the functions and types of roles are also different. University teachers are those who play a variety of roles of knowledge and society, some being the teaching teachers of organization and dissemination of knowledge, some being scientific and teaching teachers who focus on organizing and disseminating knowledge as well as knowledge creation, and knowledge creation and heavy teacher teaching and research, while others are knowledge creation based research teachers. In the field of the sociology of knowledge, university teachers should be scientific teaching roles depending on a deep knowledge and participating in knowledge in a variety of ways. From the perspective of the sociology of knowledge, according to Eph · Znaniecki＇ s role classification, university teachers participate in knowledge in three ways： teaching, learning and researching. Teaching, learning and researching are relative but different ways of participating in knowledge. State they are relative because itshows teaching can promote learning, learning can promote researching, researching can also promote learning and teaching. The homochromous interaction of teaching, leaming and researching, knowledge is in constant state of development and generation.
文摘Background To study the molecular mechanisms of CREG(the cellular repressor of E1A-stimulated gene) on proliferation of VSMCs in vitro.Methods The pRc/CMV-CREG plasmid or the pSM2-siCREG plasmid was transferred into human vascular smooth muscle cells(hVSMCs) to produce the cell clone that over-expression or down-expression of CREG respectively.BrdU assay and FACS cell cycle analysis were used to detect the proliferation of cells.Western blotting and immunocytochemistry show the expression and localization of IGF2R in hVSMCs.RT-PCR and ELISA assay determined the expression and secretion of IGFII factor. Alex488-labeled rhIGFII was used to investigate the endocysis of cells.And the blockade of IGFII internalization by treatment both the neutralized antibody of anti-IGF2R and rsIGF2R detected the effect of IGFII on VSMCs growth. Furthermore,Western blotting and signal pathway inhibitor were used to analysis the activation of PI3K/AKT and ERK on VSMCs proliferation.Results Western blotting identified that the expression of CREG in hVSMCs-CREG cells increased compared to control cell,and the decreased obviously in hVSMCs-siCREG cells.Meanwhile,the overexpression of CREG in cells was detected to inhibit the proliferation of VSMCs and to enhance the distribution of IGF2R in cellular membrane.Furthermore,overexpression of CREG also accelerated the endocysis of IGFII in hVSMCs-CREG,and attenuate the secretion of IGFII into cell medium by ELISA analysis and Alex488 labeled IGFII analysis.Blockade experiments both neutralized antibody of IGF2R and rhIGF2R fragment determined that enhancement of IGFII secretion promoted the VSMCs proliferation,and PI3K/AKT and ERK signal pathway mediated the effect of IGFII on VSMCs.Conclusions Altogether, these data indicate that CREG inhibits the proliferation of hVSMCs through interfering into the internalization pathway of IGF2R-IGFII.
文摘On the basis of clarifying the teachers'Ethics internalization theory,this paper analyzes the typical dilemma in teachers'Ethics internalization.To resolve these problems,this paper construct an overall framework,including security mechanism,normative mechanism,education mechanism,evaluation mechanism and supervision mechanism,which the external conditions are used to constantly strengthen the moral needs of the subject,then enhance the consciousness of moral internalization,improve the effectiveness of teachers'moral construction.
文摘In the Research Article “Tumor Microenvironment-Specific Chemical Internalization for Enhanced Gene Therapy of Metastatic Breast Cancer,” the authors made an error in Fig. 6A. In Fig. 6A, the image of “pre” in the “Free Cy5-siRNA” group was misused. When incorporating the final images in Fig. 6A, another image of “24 h” in the “Free Cy5-siRNA” group was inadvertently chosen as the “Pre” image, so they appear to be remarkably similar. After the error was discovered, the authors repeated the experiments that concluded that this error did not affect the results, discussion, or conclusion of this paper. Figure 6A has now been corrected in the PDF and HTML (full text).
基金supported by the Natural Science Foundation of China(82202751,Derong Xu,82372478,Chuanli Zhou,62375249,U1803128,Meng Qiu)the Taishan Scholar Project(tsqn202211362,Chuanli Zhou,tsqn201909054,Meng Qiu)+1 种基金the Natural Science Foundation of Shandong Province(ZR2021MH020,Chuanli Zhou,ZR2022JQ22,Meng Qiu)the Fundamental Research Funds for the Central Universities(202341006,Meng Qiu)。
文摘Photo-Cross-Linkable hydrogel has attracted immense interest in the regeneration of bone repair and regeneration strategies due to its superior biocompatibility and tunable mechanical properties.Recently,Nb was reported to strongly promote the bone regeneration process via an accelerated osteoblast-modulated alkaline phosphatase activity mechanism.In particular,Nb2C MXenes have drawn widespread attention due to their excellent biocompatibility and ability to induce bone formation.However,the easy agglomeration of Nb2C nanosheets and subsequent low cell endocytosis efficacy greatly suppressed the osteogenesis effect.In this study,a subtractive nanopore-engineered Nb2C MXene was prepared through a microwave combustion method,gelatin methacrylate was used as the carrier hydrogel,and the photo-triggered Porous-Nb2C@GelMA hydrogel was fabricated by a photo-triggered process.The pore-forming strategy not only successfully improved the distribution of Nb2C and formed more homogenous Porous-Nb2C@GelMA hydrogels but also guided bone marrow mesenchymal stem cells(BMSCs)toward osteoblast differentiation.Porous Nb2C provided convenient cellular grasping and endocytosis for BMSCs,which further created a favorable environment for differentiation and osteogenesis.This,in turn,leads to an increase in the expression of osteogenic markers,such as ALP and ARS,as well as osteogenic factors,such as BMP-2,COL-1,OCN,and OPN.Consequently,enhancing the regenerative microenvironment by incorporating porous Nb2C composite hydrogels shows promise for application in bone regeneration.
基金supported by the National Key R&D Program of China(2022YFF0710500)the the National Natural Science Foundation,China(31802192,32172853 and 32373013)+2 种基金the Natural Science Foundation of Heilongjiang Province of China(C2018070)China Postdoctoral Science Foundation(2017M620076)the Central Public-interest Scientific Institution Basal Research Fund,China(1610302022001)。
文摘Salmonella enterica serovar Typhimurium,the causative agent of gastroenteritis,is one of the most successful intracellular pathogens.Although certain host factors for Salmonella infection have been unveiled,the factors mediating Salmonella entry,particularly the invasion process,remain obscure.Here,we have unearthed β2 integrin,a crucial member of the integrin family,as an important host factor facilitating Salmonella invasion.It is demonstrated that overexpression of β2 integrin promotes Salmonella invasion,while the knockdown of β2 integrin significantly diminishes the extent of invasion.Moreover,Salmonella exhibits specific binding affinity towards β2 integrin,and the block of β2 integrin on cell surface substantially reduces the infection of cells in vitro.The ectodomain soluble protein of β2 integrin neutralized Salmonella infection both in cells(in vitro)and in mice(in vivo).Additionally,Salmonella protein YrbD directly interacts with β2 integrin to facilitate its invasion.To our knowledge,this study showed for the first time that the protein YrbD mediates Salmonella adhesion and internalization into host cells by interacting with β2 integrin.These findings not only broaden our understanding of the mechanisms underlying Salmonella entry,but also identify a prospective target for therapeutic control.
基金supported by the Natural Science Foundation of Guangxi Zhuang Automomous Region,Nos.2019GXNSFDA245015(to MC),2022GXNSFBA035654(to HL)the National Natural Science Foundation of China,Nos.82360241(to MC),82304876(to HL)+1 种基金Scientific Research and Technology Development Project of Guilin City,Nos.20220139-3(to MC),20210218-5(to HL)Guangxi Medical and Health Key Discipline Construction Project(to QL)。
文摘α-Synuclein accumulation and transmission are vital to the pathogenesis of Parkinson's disease,although the mechanisms underlying misfoldedα-synuclein accumulation and propagation have not been conclusively determined.The expression of low-density lipoprotein receptor–related protein 1,which is abundantly expressed in neurons and considered to be a multifunctional endocytic receptor,is elevated in the neurons of patients with Parkinson's disease.However,whether there is a direct link between low-density lipoprotein receptor–related protein 1 andα-synuclein aggregation and propagation in Parkinson's disease remains unclear.Here,we established animal models of Parkinson's disease by inoculating monkeys and mice withα-synuclein pre-formed fibrils and observed elevated low-density lipoprotein receptor–related protein 1 levels in the striatum and substantia nigra,accompanied by dopaminergic neuron loss and increasedα-synuclein levels.However,low-density lipoprotein receptor–related protein 1 knockdown efficiently rescued dopaminergic neurodegeneration and inhibited the increase inα-synuclein levels in the nigrostriatal system.In HEK293A cells overexpressingα-synuclein fragments,low-density lipoprotein receptor–related protein 1 levels were upregulated only when the N-terminus ofα-synuclein was present,whereas anα-synuclein fragment lacking the N-terminus did not lead to low-density lipoprotein receptor–related protein 1 upregulation.Furthermore,the N-terminus ofα-synuclein was found to be rich in lysine residues,and blocking lysine residues in PC12 cells treated withα-synuclein pre-formed fibrils effectively reduced the elevated low-density lipoprotein receptor–related protein 1 andα-synuclein levels.These findings indicate that low-density lipoprotein receptor–related protein 1 regulates pathological transmission ofα-synuclein from the striatum to the substantia nigra in the nigrostriatal system via lysine residues in theα-synuclein N-terminus.
