Neuronal cell death is a common outcome of multiple pathophysiological processes and a key factor in neurological dysfunction after subarachnoid hemorrhage.Neuronal ferroptosis in particular plays an important role in...Neuronal cell death is a common outcome of multiple pathophysiological processes and a key factor in neurological dysfunction after subarachnoid hemorrhage.Neuronal ferroptosis in particular plays an important role in early brain injury.Bromodomain-containing protein 4,a member of the bromo and extraterminal domain family of proteins,participated in multiple cell death pathways,but the mechanisms by which it regulates ferroptosis remain unclear.The primary aim of this study was to investigate how bromodomain-containing protein 4 affects neuronal ferroptosis following subarachnoid hemorrhage in vivo and in vitro.Our findings revealed that endogenous bromodomain-containing protein 4 co-localized with neurons,and its expression was decreased 48 hours after subarachnoid hemorrhage of the cerebral cortex in vivo.In addition,ferroptosis-related pathways were activated in vivo and in vitro after subarachnoid hemorrhage.Targeted inhibition of bromodomain-containing protein 4 in neurons increased lipid peroxidation and intracellular ferrous iron accumulation via ferritinophagy and ultimately led to neuronal ferroptosis.Using cleavage under targets and tagmentation analysis,we found that bromodomain-containing protein 4 enrichment in the Raf-1 promoter region decreased following oxyhemoglobin stimulation in vitro.Furthermore,treating bromodomain-containing protein 4-knockdown HT-22 cell lines with GW5074,a Raf-1 inhibitor,exacerbated neuronal ferroptosis by suppressing the Raf-1/ERK1/2 signaling pathway.Moreover,targeted inhibition of neuronal bromodomain-containing protein 4 exacerbated early and long-term neurological function deficits after subarachnoid hemorrhage.Our findings suggest that bromodomain-containing protein 4 may have neuroprotective effects after subarachnoid hemorrhage,and that inhibiting ferroptosis could help treat subarachnoid hemorrhage.展开更多
Dysregulated inflammation and multi-organ failure are hallmarks of sepsis,a potentially fatal illness for which there are currently no effective treatments.Fatty acid-binding protein(A-FABP)has been identified in rece...Dysregulated inflammation and multi-organ failure are hallmarks of sepsis,a potentially fatal illness for which there are currently no effective treatments.Fatty acid-binding protein(A-FABP)has been identified in recent research as a crucial mediator of the inflammatory pathways underlying sepsis.In this study,we used a murine model of lipopolysaccharide(LPS)-induced endotoxemia to assess the therapeutic potential of 6H2,a monoclonal antibody that targets A-FABP.In comparison to untreated septic mice,6H2 treatment significantly increased survival rates,decreased histopathological damage in the liver,lungs,kidneys,and heart,and reduced systemic inflammation.According to biochemical analyses,6H2 treatment decreased circulating levels of A-FABP,and this was associated with a reduction in inflammatory markers.These results indicate that A-FABP inhibition is a potentially effective treatment approach for sepsis,with 6H2 demonstrating strong therapeutic efficacy.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
Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immun...Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immune tolerance of cancer cells.The classical theory holds that prostate apoptosis response-4(PAR-4)is a tumor suppressor protein.However,our recent research has found that PAR-4 has a biological function of promoting cancer in hepatocellular carcinoma(HCC),and our analysis shows that PAR-4 can be modified of lactic acid.These research evidences suggest that PAR-4 lactylation modification may drive immune tolerance in HCC.Therefore,inhibiting PAR-4 lactylation modification is very likely to increase the sensitivity of HCC to immunotherapy.展开更多
Objective: To explore the effect of L158, 809 (angiatensin Ⅱ receptorMockers, ARBs) and Cilazapril (Angiotensin converting enzyme inhibitor, ACEI) on the expression oftransforming growth factor-β_1 (TGF-β_1) and se...Objective: To explore the effect of L158, 809 (angiatensin Ⅱ receptorMockers, ARBs) and Cilazapril (Angiotensin converting enzyme inhibitor, ACEI) on the expression oftransforming growth factor-β_1 (TGF-β_1) and secretion of fibronectin, laminin and type Ⅳcollagen from the cultured human mesangial cells . Methods: Human mesangial cells were cultured indifferent glucose (5.6 mmol/L and 30 mmol/L) and agents (1, 10, 100 and 500 μmol/L) concentrations. The proliferation of mesangial cells were detected at 24, 48 and 72 h . Then the mesangial cellsare divided into four groups, low glucose (5.6 mmol/L) control group, high glucose (30 mmol/L)control group , L158, 809 (10 μmol/L) group and cilazapril (10 μmol/L) group. Forty- eight hourslater, the expression of TGF-β_1 were detected by RT-PCR. Concentrations of TGF-β_1 ,fibronection, laminin and type Ⅳ collagen in the su-pematants of the, mesangial cells weredetermined by EUSA and radioimmunoassay methods. Results: Compared with low glucose control group,the mesangial cells under high glucose medium show excessive proliferation and more TGF-β_1,fibronectin, laminin and type Ⅳ collagen in the supernatant. The expression of TGF-β_1 mRNA wasalso significantly increased under high glucose. The levels of TGF-β_1 and ECM (extracellularmatrix) proteins in the L158, 809 group and cilazapril group are obviously lower than that of thehigh glucose control group. The expression of TGF-β_1 mRNA was markedly decreased in the L158, 809group and cilazapril group compared with that of high glucose control group . Conclusion: Highglucose stimulated the cultured human mesangial cells to excessively proliferate, express TGF-β_1and secrete ECM proteins, and the high glucose-indeced changes were suppressed by either L158, 809and cilazapril.展开更多
The effect of pH values on the extracellular protein and polysaccharide secretions of Acidithiobacillus ferrooxidans was comparatively investigated in different phases of bacterial growth during chalcopyrite bioleachi...The effect of pH values on the extracellular protein and polysaccharide secretions of Acidithiobacillus ferrooxidans was comparatively investigated in different phases of bacterial growth during chalcopyrite bioleaching. The results indicate that the extracellular protein is always more than the extracellular polysaccharide secreted by attached cells on the chalcopyrite, on the contrary, and is always less than the extracellular polysaccharide secreted by free cells in the solution at bacterial adaptive phase, logarithmic phase and stationary phase whenever pH value is at 1.0, 1.5, 2.0 or 2.5; free cells are mainly through the secretion of extracellular polysaccharide rather than the extracellular protein to fight against disadvantageous solution environment, such as high concentration of metal ions and unsuitable pH solution; both amounts of polysaccharide and protein secreted by attached cells are mainly positively related to the solution acidity rather than the total concentration of soluble metal ions. The experimental results imply that bacteria are mainly through secreting more extracellular polysaccharide to fight against disadvantageous environment and the extracellular protein perhaps plays an important role in oxidation?reduction reactions in the bioleaching system.展开更多
This study examined the effect of GHRP-6, a known GHSs receptor agonist, on the phosphorylation of cAMP-responsive element-binding protein (CREB) and the tmderly mechanism. GH3 cells were cultured and subjected to d...This study examined the effect of GHRP-6, a known GHSs receptor agonist, on the phosphorylation of cAMP-responsive element-binding protein (CREB) and the tmderly mechanism. GH3 cells were cultured and subjected to different treatments as follows: GHRP-6, GHRP-6 plus GHRH, phorbol ester (PMA), an activator of PKC, alone or in combination with GHRP-6, G66983, a general inhibitor of PKCs, in the presence or absence of GHRP-6, rottlerin, an inhibitor of PKCs, alone or plus GHRP-6. The cells were transiently transfected with PKCσ-specific siRNA and then treated with GHRP-6. GH level was measured by enzyme-linked immunosorbent assay (ELISA). The expression of phosphor-CREB, PKCσ, PKC0 and phosphor-PKCo was determined by Western blotting. The results showed that GHRP-6 stimulated GH secretion in both time- and dose-dependent manners and enhanced the effect of GHRH on GH secretion. GHRP-6 was also found to induce CREB phosphorylation. Moreover, GH secretion was enhanced by the PKC activator PMA and reduced by the PKC inhibitors (G66983, rottlerin) and knockdown of PKCσ. PKCσ could be activated by GHRP-6. It is concluded that PKC, especialiy PKCσ, mediates CREB phosphorylation and GHRP-6-induced GH secretion.展开更多
BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion.The aims of this study were to investigate t...BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion.The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion.METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls.Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry.SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence.RESULTS:Insulinoma patients presented the typical demons-trations of Whipple’s triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients.Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets.CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1.In contrast,MRP1,which is down-regulated in insulinomas,might reflect a negative feedback in insulin secretion.展开更多
DEAR EDITOR,Extracellular vesicles(EVs)are important for the transport of biologically active materials and for intercellular communication.As an exposed mucosa,amphibian skin participates in many essential physiologi...DEAR EDITOR,Extracellular vesicles(EVs)are important for the transport of biologically active materials and for intercellular communication.As an exposed mucosa,amphibian skin participates in many essential physiological processes.To date,however,little is known about EVs in amphibian skin.Here,we successfully isolated EVs from the skin secretions of Bombina maxima,and characterized the EVs using nanoparticle tracking,western blotting,and electron microscopy.展开更多
To investigate dietary protein level effects on digestive mechanisms, weaned piglets were fed for 45 d with diets containing 20%, 17%, or 14% crude protein (CP) supplemented to meet requirements for essential amino ...To investigate dietary protein level effects on digestive mechanisms, weaned piglets were fed for 45 d with diets containing 20%, 17%, or 14% crude protein (CP) supplemented to meet requirements for essential amino acids. This article describes the influence of dietary protein on gastrointestinal hormones and expression of an array of digestive enzymes in the gastrointestinal tract and pancreas. Results indicated that there were no significant differ- ences in expression of enzymes involved in carbohydrate digestion, except for maltase in the duodenum. In the je- junum, amylase expression in pigs fed 20% CP was much higher than that in pigs fed other diets (P〈0.05) and maltase expression in those fed 17% CP was higher than that in other treatments (P〈0.05). Although there were no remarkable differences in expression of aminopeptidase in the small intestine or carboxypeptidase in the pancreas (P〉0.05), there was a trend towards higher expression of various proteases in pigs fed 17% CP. The duodenal expression of en- teropeptidase in diets with 14% and 17% CP was significantly higher than that with 20% CP (P〈0.05), but treatment differences did not existed in jejunum (P〉0.05). The expression of GPR93 as a nutrient-responsive G protein-coupled receptor in 14% and 17% CP diets was significantly higher than that in 20% CP diet in the small intestine (P〈0.05). The expressions of genes for pancreatic enzymes, lipase and elastase, were significantly higher in pigs fed diets with low CP, while similar trends occurred for carboxypeptidase, chymotrypsin and amylase. Conversely, the gastric expres- sions of pepsinogen A and progastricsin were lower with the 17% CP diet. Differences between treatments were found in the gastric antral contents of cholecystokinin and somatostatin: both increased in pigs fed 17% CP, accompanied by decreased content of motilin, which was also seen in plasma concentrations. These patterns were not reflected in duodenal contents. In general, 17% dietary CP was beneficial to the digestion of nutrient substance in the gastroin- testinal tract.展开更多
The axonal compartment of developing neurons and mature peripheral nervous system (PNS) neurons has the capacity to locally synthesize proteins. Axonally-synthesized proteins have been shown to facilitate axonal pat...The axonal compartment of developing neurons and mature peripheral nervous system (PNS) neurons has the capacity to locally synthesize proteins. Axonally-synthesized proteins have been shown to facilitate axonal pathfinding and maintenance in developing central nervous system (CNS) and PNS neurons, and to facilitate the regeneration of mature PNS neurons. RNA-profiling studies of the axons of cultured neurons have shown a surprisingly complex population of mRNAs that encode proteins for a myriad of functions. Although classic-appearing rough endoplasmic reticulum (RER), smooth endoplasmic reticulum (ER) and Golgi apparatus have not been documented in axons by ultrastructural studies, axonal RNA profiling studies show several membrane and secreted protein-encoding mRNAs whose translation products would need access to a localized secretory mechanism. We previously showed that the axons of cultured neurons contain functional equivalents of RER and Golgi apparatus. Here, we show that markers for the signal-recognition particle, RER, ER, and Golgi apparatus are present in PNS axons in vivo. Co-localization of these proteins mirrors that seen for cultured axons where locally-translated proteins are localized to the axoplasmic membrane. Moreover, nerve injury increases the levels and/or aggregation of these proteins, suggesting that the regenerating axon has an increased capacity for membrane targeting of locally synthesized proteins.展开更多
In this study, Va 1686 gene was cloned from Vibrio alginolyticus . The total length of the gene is 1 164 bp, and it could encode 387 amino acids. The physicochemical properties, protein structure, genetic evolutionary...In this study, Va 1686 gene was cloned from Vibrio alginolyticus . The total length of the gene is 1 164 bp, and it could encode 387 amino acids. The physicochemical properties, protein structure, genetic evolutionary relationship and antigenic characteristics of the effect protein Va1686 of V. alginolyticus HY9901 type Ⅲ secretion system were studied and analyzed by bioinformatics methods and tools. The results showed that Va1686 is a stable hydrophilic and acidic protein without a transmembrane region and a signal peptide, and secondary structure to α-helix. The evolutionary analysis showed that V. alginolyticus HY9901 and V. harveyi were clustered together, which indicated that the genetic relationship between the two species was the closest. Va1686 contains a Fic superfamily conserved domain associated with cell division. Bioinformatics analysis showed that the B-cell preponderant epitopes of Va1686 might be localized in the regions of 48-49, 82-85, 125-126, 150-153, 185-186, 236-237 and so on. The 3D structure model of Va1686 subunit was simulated by SWISS-MODEL software and it was found that the vopS of V. parahaemolyticus was similar and the similarity was 89.46%. In this study, the feasibility of Va1686 as a common antigen of Vibrio was verified from the perspective of bioinformatics, which laid the foundation for the next step in vaccine development.展开更多
AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,...AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,which serve as a model for enteroendocrine L-cells,by quantitative reverse transcription-polymerase chain reaction and Western blotting before and after treatment with oleic acid.Localization of UCP2 and GLP-1 in NCI-H716 cells was assessed by immunofluorescence labeling.NCI-H716 cells were transiently transfected with a small interfering RNA(siRNA) that targets UCP2(siUCP2) or with a nonspecific siRNA using Lipofectamine 2000.The concentrations of bioactive GLP-1 in the medium were measured by enzyme linked immunosorbent assay.RESULTS:Both GLP-1 and UCP2 granules were expressed mainly in the cytoplasm of NCI-H716 cells.NCI-H716 cells that secreted GLP-1 also expressed UCP2.Time-course experiments revealed that release of GLP-1 from NCI-H716 cells into the medium reached a maximum at 120 min and remained stable until at least 180 min after treatment with oleic acid(the level of GLP-1 increased about 2.3-fold as compared with the level of GLP-1 in the control cells,P < 0.05).In an experiment to determine dose dependence,stimulation of NCI-H716 cells with ≤ 8 mmol oleic acid led to a concentration-dependent release of GLP-1 into the medium;10 mmol oleic acid diminished the release of GLP-1.Furthermore,GLP-1 secretion induced by oleic acid from NCI-H716 cells that were transfected with siUCP2 decreased to 41.8%,as compared with NCI-H716 cells that were transfected with a non-specific siRNA(P < 0.01).CONCLUSION:UCP2 affected GLP-1 secretion induced by oleic acid.UCP2 plays an important role in L-cell secretion that is induced by free fatty acids.展开更多
AIM: To examine the existence of Nitric oxide/ cGMP sensitive store-operated Ca^2+ entry in mouse fibroblast NIH/3T3 cells and its influence on matrix metalloproteinase (MMP) production and adhesion ability of fib...AIM: To examine the existence of Nitric oxide/ cGMP sensitive store-operated Ca^2+ entry in mouse fibroblast NIH/3T3 cells and its influence on matrix metalloproteinase (MMP) production and adhesion ability of fibroblasts. METHODS: NIH/3T3 cells were cultured. Confocal laser scanning microscopy was used to examine the existence of thapsigargin-induced store-operated Ca^2+ entry in fibroblasts. Gelatin zymography and semiquantitative reverse transcriptase-polymerase chain reaction (RTPCR) were employed to detect the involvement of [Ca^2+]i and NO/cGMP in MMP secretion. The involvement of NO/ cGMP-sensitive Ca^2+ entry in adhesion was determined using matrigel-coated culture plates. RESULTS: 8-bromo-cGMP inhibited the thapsigargin-induced Ca^2+ entry in 3T3 cells. The cGMP-induced inhibition was abolished by an inhibitor of protein kinase G, KT5823 (1μmol/L). A similar effect on the Ca^2+ entry was observed in 3T3 cells in response to a NO donor, (±)-S-nitroso-N-acetylpenicillamine (SNAP). The inhibitory effect of SNAP on the thapsigargin-induced Ca^2+ entry was also observed, indicating NO/cGMP-regulated Ca^2+ entry in 3T3 cells. Results of gelatin zymography assay showed that addition of extracellular Ca^2+ concentration induced MMP release and activation in a dose-dependent manner. RT-PCR also showed that cGMP and SNAP reduced the production of MMP mRNA in 3T3 cells. Experiments investigating adhesion potentials demonstrated that cGMP and SNAP could upgrade 3T3 cell attachment rate to the matrigel-coated culture plates.CONCLUSION: NO/cGMP sensitive store-operated Ca^2+ entry occurs in fibroblasts, and attenuates their adhesion potentials through its influence on MMP secretion.展开更多
Objective: To provide the experimental basis for further studying the molecular transformation mechanism of Hepatitis B virus (HBV) X protein (HBx) on hepatocellular carcinoma. Methods: Reconstructed plasmid pcD...Objective: To provide the experimental basis for further studying the molecular transformation mechanism of Hepatitis B virus (HBV) X protein (HBx) on hepatocellular carcinoma. Methods: Reconstructed plasmid pcDNA3.1(+)-HBx was transfected into THP-1 macrophages. Expression of HBx was assayed in macrophages lysate by Western-blotting, and TNF-α and IL-1β contents were detected respectively by ELISA. All the data were analyzed by SPSS13.0. Results: In THP-lmacrophages, the pcDNA3.1(+)-HBx plasmid expressed HBx with a molecular weight of about 17 KDa demonstrated by Western-blotting. The secreted TNF-α and IL-1β from macrophages were determined by ELISA, the results from analysis of all groups showed as following: control group was different from LPS group and pcDNA3.1(+) group (P〈0.01), and so was pcDNA3.1(+)-HBx group; but there was no obvious difference between pcDNA3.1(+) group and LPS group (P〉0.05), all of which indicated that transient overexpression of HBx enhanced LPS-induced production of TNF-α and IL-1β by macrophages. Conclusion: Transient overexpression of HBx up-regulates LPS-induced TNF-t~ and IL-113 secretion of macrophages.展开更多
The present study was to investigate the effect of monoclonal antibody against porcine 40-kDa adipocyte-specific membrane protein on endocrine secretion in pigs, in order to provide the evidence for application of thi...The present study was to investigate the effect of monoclonal antibody against porcine 40-kDa adipocyte-specific membrane protein on endocrine secretion in pigs, in order to provide the evidence for application of this antibody to reduce excessive fat deposition in pig production. 40 Landrace×Saba pigs were randomly divided into 8 groups: 2 control groups were given saline with 10 mL, respectively, and the 6 treatment groups were given monoclonal antibody against porcine 40-kDa adipocyte-specific membrane protein with 0.1, 0.5, and 1.0 mg ·kg^-1 body weight at 15 or 60 kg body weight, respectively, all treatments were performed by intraperitoneal injection. The results showed that this monoclonal antibody could significantly reduce serum insulin level and increase levels of serum growth hormone (GH), insulin-like growth factor-1(IGF-1), triiodothyronine (T3), and tetraiodothyronine (T4) either at 15 or 60 kg body weight injection. However, more marked effect was observed at 15 kg body weight treatment. Moreover, the dose-dependent effect of this monoclonal antibody on endocrine secretion was also observed. This result revealed that this monoclonal antibody increased secretion of hormones regulating fat lysis and reduced secretion of hormones regulating fat synthesis, suggests the reduction of porcine excessive fat deposition by this monoclonal antibody was carried out through affecting hormones regulating fat metabolism.展开更多
AIM: We have previously demonstrated that hepatitis C virus (HCV) core protein is efficiently released into the culture medium in insect cells. The objective of this study is to characterize the HCV core secretion in ...AIM: We have previously demonstrated that hepatitis C virus (HCV) core protein is efficiently released into the culture medium in insect cells. The objective of this study is to characterize the HCV core secretion in insect cells. METHODS: We constructed recombinant baculoviruses expressing various-length of mutant core proteins, expressed these proteins in insect cells, and examined core protein secretion in insect cells. RESULTS: Only wild type core was efficiently released into the culture medium, although the protein expression level of wild type core was lower than those of other mutant core proteins. We found that the shorter form of the core construct expressed the higher level of protein. However, if more than 18 amino acids of the core were truncated at the C-terminus, core proteins were no longer secreted into the culture medium. Membrane flotation data show that the secreted core proteins are associated with the cellular membrane protein, indicating that HCV core is secreted as a membrane complex. CONCLUSION: The C-terminal 18 amino acids of HCV core were crucial for core secretion into the culture media. Since HCV replication occurs on lipid raft membrane structure, these results suggest that HCV may utilize a unique core release mechanism to escape immune surveillance, thereby potentially representing the feature of HCV morphogenesis.展开更多
Ma et al recently reported in the World Journal of Diabetes that ferroptosis occurs in osteoblasts under high glucose conditions,reflecting diabetes pathology.This condition could be protected by the upregulation of t...Ma et al recently reported in the World Journal of Diabetes that ferroptosis occurs in osteoblasts under high glucose conditions,reflecting diabetes pathology.This condition could be protected by the upregulation of the gene encoding polycytosine RNA-binding protein 1(PCBP1).Additionally,Ma et al used a lentivirus infection system to express PCBP1.As the authors’method of administration can be improved in terms of stability and cost,we propose delivering PCBP1 to treat type 2 diabetic osteoporosis by encapsulating it in protein nanoparticles.First,PCBP1 is small and druggable.Second,intravenous injection can help deliver PCBP1 across the mucosa while avoiding acid and enzyme-catalyzed degradation.Furthermore,incorporating PCBP1 into nanoparticles prevents its interaction with water or oxygen and protects PCBP1’s structure and activity.Notably,the safety of the protein materials and the industrialization techniques for large-scale production of protein nanoparticles must be comprehensively investigated before clinical application.展开更多
In this study,Hy322 gene was cloned from Vibrio alginolyticus.The total length of its gene was 969 bp,and it could encode 322 amino acids.The physicochemical properties,protein structure,genetic evolutionary relations...In this study,Hy322 gene was cloned from Vibrio alginolyticus.The total length of its gene was 969 bp,and it could encode 322 amino acids.The physicochemical properties,protein structure,genetic evolutionary relationship and antigenic characteristics of the effector protein Hy322 of V.alginolyticus HY9901 type Ⅲ secretion system were studied and analyzed by bioinformatics methods and tools.The results showed that Hy322 is an unstable hydrophilic and acidic protein without a transmembrane region and a signal peptide,and secondary structure to α-helix.The evolutionary analysis showed that V.alginolyticus HY9901 and V.harveyi were clustered together,which indicated that the genetic relationship between the two species was closest.HY322 contains a FliN super family conserved domain associated with Flagellar motor switch.Bioinformatics analysis showed that the B-cell preponderant epitopes of Hy322 might be localized in the regions of 32-33,100-102,138-140,215-216,235-238 and 246-249.The 3D structure model of Hy322 subunit was simulated by SWISS-MODEL software and itwas found that the yscQ of Yersinia were similar and the similarity was 42.25%.In this study,the feasibility of Hy322 as a common antigen of Vibrio was verified from the perspective of bioinformatics,which laid the foundation for the next step in vaccine development.展开更多
In this study the effect of human recombinant interferon gamma hrIFN-γ)on hCG secretion of human first trimester trophoblast and protein synthesis of decidual tissue was investigated in vitro.The results indicated th...In this study the effect of human recombinant interferon gamma hrIFN-γ)on hCG secretion of human first trimester trophoblast and protein synthesis of decidual tissue was investigated in vitro.The results indicated that hrIFN-γat the doses of 250 U/ml medium and 2500 U/ml medium decreased hCG secretion of trophoblast obviously(P<0.05, P<0.01)in a dose dependent manner.The effect of hrIFN-γon protein synthesis at the doses of 10 U to 1,000 U/ml medium inhibited the 3H leucine incorporation obviously.The cpm values between control and experimental groups were significantly different(P<0. 05) in a dosedependent manner.Furthermore its inhibitory effect is in a dose-dependent manner and was neutralized by IFN-γantiserum.The IFN-a at the doses used did not find any effect on protein synthesis in decidual tissue.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82371310(to YJ),82271306(to JP)the Sichuan Science and Technology Support Program,Nos.2023YFH0069(to JP),2023NSFSC0028(to YJ),2023NSFSC1559(to YJ),2022YFS0615(to JP),2022NSFSC1421(to JP)+1 种基金Scientific Research Project of Sichuan Provincial Health Commission,No.23LCYJ040(to YJ)Youth Foundation of Southwestern Medical University and Southwest Medical University Project,Nos.2020ZRQNA038(to JP),2021ZKZD013(to JP),2021LZXNYD-P01(to YJ),2023QN014(to JP).
文摘Neuronal cell death is a common outcome of multiple pathophysiological processes and a key factor in neurological dysfunction after subarachnoid hemorrhage.Neuronal ferroptosis in particular plays an important role in early brain injury.Bromodomain-containing protein 4,a member of the bromo and extraterminal domain family of proteins,participated in multiple cell death pathways,but the mechanisms by which it regulates ferroptosis remain unclear.The primary aim of this study was to investigate how bromodomain-containing protein 4 affects neuronal ferroptosis following subarachnoid hemorrhage in vivo and in vitro.Our findings revealed that endogenous bromodomain-containing protein 4 co-localized with neurons,and its expression was decreased 48 hours after subarachnoid hemorrhage of the cerebral cortex in vivo.In addition,ferroptosis-related pathways were activated in vivo and in vitro after subarachnoid hemorrhage.Targeted inhibition of bromodomain-containing protein 4 in neurons increased lipid peroxidation and intracellular ferrous iron accumulation via ferritinophagy and ultimately led to neuronal ferroptosis.Using cleavage under targets and tagmentation analysis,we found that bromodomain-containing protein 4 enrichment in the Raf-1 promoter region decreased following oxyhemoglobin stimulation in vitro.Furthermore,treating bromodomain-containing protein 4-knockdown HT-22 cell lines with GW5074,a Raf-1 inhibitor,exacerbated neuronal ferroptosis by suppressing the Raf-1/ERK1/2 signaling pathway.Moreover,targeted inhibition of neuronal bromodomain-containing protein 4 exacerbated early and long-term neurological function deficits after subarachnoid hemorrhage.Our findings suggest that bromodomain-containing protein 4 may have neuroprotective effects after subarachnoid hemorrhage,and that inhibiting ferroptosis could help treat subarachnoid hemorrhage.
文摘Dysregulated inflammation and multi-organ failure are hallmarks of sepsis,a potentially fatal illness for which there are currently no effective treatments.Fatty acid-binding protein(A-FABP)has been identified in recent research as a crucial mediator of the inflammatory pathways underlying sepsis.In this study,we used a murine model of lipopolysaccharide(LPS)-induced endotoxemia to assess the therapeutic potential of 6H2,a monoclonal antibody that targets A-FABP.In comparison to untreated septic mice,6H2 treatment significantly increased survival rates,decreased histopathological damage in the liver,lungs,kidneys,and heart,and reduced systemic inflammation.According to biochemical analyses,6H2 treatment decreased circulating levels of A-FABP,and this was associated with a reduction in inflammatory markers.These results indicate that A-FABP inhibition is a potentially effective treatment approach for sepsis,with 6H2 demonstrating strong therapeutic efficacy.
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.
基金supported by the National Natural Science Foundation of China(Nos.82573045,82460602,82560459)the Hainan Provincial Graduate Student Innovative Research Project(No.Qhys2024-440).
文摘Post-translational modifications(PTMs)regulate the occurrence and development of cancer,and lactylation modification is a new form of PTMs.Recent studies have found that lactic acid modification can regulate the immune tolerance of cancer cells.The classical theory holds that prostate apoptosis response-4(PAR-4)is a tumor suppressor protein.However,our recent research has found that PAR-4 has a biological function of promoting cancer in hepatocellular carcinoma(HCC),and our analysis shows that PAR-4 can be modified of lactic acid.These research evidences suggest that PAR-4 lactylation modification may drive immune tolerance in HCC.Therefore,inhibiting PAR-4 lactylation modification is very likely to increase the sensitivity of HCC to immunotherapy.
基金National Science and Technology Ninth 5-year Project of Medicine(96-906-05-0)
文摘Objective: To explore the effect of L158, 809 (angiatensin Ⅱ receptorMockers, ARBs) and Cilazapril (Angiotensin converting enzyme inhibitor, ACEI) on the expression oftransforming growth factor-β_1 (TGF-β_1) and secretion of fibronectin, laminin and type Ⅳcollagen from the cultured human mesangial cells . Methods: Human mesangial cells were cultured indifferent glucose (5.6 mmol/L and 30 mmol/L) and agents (1, 10, 100 and 500 μmol/L) concentrations. The proliferation of mesangial cells were detected at 24, 48 and 72 h . Then the mesangial cellsare divided into four groups, low glucose (5.6 mmol/L) control group, high glucose (30 mmol/L)control group , L158, 809 (10 μmol/L) group and cilazapril (10 μmol/L) group. Forty- eight hourslater, the expression of TGF-β_1 were detected by RT-PCR. Concentrations of TGF-β_1 ,fibronection, laminin and type Ⅳ collagen in the su-pematants of the, mesangial cells weredetermined by EUSA and radioimmunoassay methods. Results: Compared with low glucose control group,the mesangial cells under high glucose medium show excessive proliferation and more TGF-β_1,fibronectin, laminin and type Ⅳ collagen in the supernatant. The expression of TGF-β_1 mRNA wasalso significantly increased under high glucose. The levels of TGF-β_1 and ECM (extracellularmatrix) proteins in the L158, 809 group and cilazapril group are obviously lower than that of thehigh glucose control group. The expression of TGF-β_1 mRNA was markedly decreased in the L158, 809group and cilazapril group compared with that of high glucose control group . Conclusion: Highglucose stimulated the cultured human mesangial cells to excessively proliferate, express TGF-β_1and secrete ECM proteins, and the high glucose-indeced changes were suppressed by either L158, 809and cilazapril.
基金Project(31200382)supported by the National Natural Science Foundation of China
文摘The effect of pH values on the extracellular protein and polysaccharide secretions of Acidithiobacillus ferrooxidans was comparatively investigated in different phases of bacterial growth during chalcopyrite bioleaching. The results indicate that the extracellular protein is always more than the extracellular polysaccharide secreted by attached cells on the chalcopyrite, on the contrary, and is always less than the extracellular polysaccharide secreted by free cells in the solution at bacterial adaptive phase, logarithmic phase and stationary phase whenever pH value is at 1.0, 1.5, 2.0 or 2.5; free cells are mainly through the secretion of extracellular polysaccharide rather than the extracellular protein to fight against disadvantageous solution environment, such as high concentration of metal ions and unsuitable pH solution; both amounts of polysaccharide and protein secreted by attached cells are mainly positively related to the solution acidity rather than the total concentration of soluble metal ions. The experimental results imply that bacteria are mainly through secreting more extracellular polysaccharide to fight against disadvantageous environment and the extracellular protein perhaps plays an important role in oxidation?reduction reactions in the bioleaching system.
基金supported by a grant from the National Natural Sciences Foundation of China (No. 30672161)
文摘This study examined the effect of GHRP-6, a known GHSs receptor agonist, on the phosphorylation of cAMP-responsive element-binding protein (CREB) and the tmderly mechanism. GH3 cells were cultured and subjected to different treatments as follows: GHRP-6, GHRP-6 plus GHRH, phorbol ester (PMA), an activator of PKC, alone or in combination with GHRP-6, G66983, a general inhibitor of PKCs, in the presence or absence of GHRP-6, rottlerin, an inhibitor of PKCs, alone or plus GHRP-6. The cells were transiently transfected with PKCσ-specific siRNA and then treated with GHRP-6. GH level was measured by enzyme-linked immunosorbent assay (ELISA). The expression of phosphor-CREB, PKCσ, PKC0 and phosphor-PKCo was determined by Western blotting. The results showed that GHRP-6 stimulated GH secretion in both time- and dose-dependent manners and enhanced the effect of GHRH on GH secretion. GHRP-6 was also found to induce CREB phosphorylation. Moreover, GH secretion was enhanced by the PKC activator PMA and reduced by the PKC inhibitors (G66983, rottlerin) and knockdown of PKCσ. PKCσ could be activated by GHRP-6. It is concluded that PKC, especialiy PKCσ, mediates CREB phosphorylation and GHRP-6-induced GH secretion.
文摘BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion.The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion.METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls.Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry.SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence.RESULTS:Insulinoma patients presented the typical demons-trations of Whipple’s triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients.Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets.CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1.In contrast,MRP1,which is down-regulated in insulinomas,might reflect a negative feedback in insulin secretion.
基金supported by the National Natural Science Foundation of China(31572268,U1602225,31872226)Yunling Scholar Program to Y.Z.,and the Basic Research of Yunnan Province(202101AT070292)to X.L.G.
文摘DEAR EDITOR,Extracellular vesicles(EVs)are important for the transport of biologically active materials and for intercellular communication.As an exposed mucosa,amphibian skin participates in many essential physiological processes.To date,however,little is known about EVs in amphibian skin.Here,we successfully isolated EVs from the skin secretions of Bombina maxima,and characterized the EVs using nanoparticle tracking,western blotting,and electron microscopy.
基金supported by the National Basic Research Program(973)of China(Nos.2013CB127301 and 2013CB127304)the Guangdong International Science and Technology Cooperation Program(No.2014A050503049)+1 种基金the China Agriculture Research System(No.CARS-36)the Science and Technology Program of Guangdong Province(Nos.2013A061401020 and 2016A020210041),China
文摘To investigate dietary protein level effects on digestive mechanisms, weaned piglets were fed for 45 d with diets containing 20%, 17%, or 14% crude protein (CP) supplemented to meet requirements for essential amino acids. This article describes the influence of dietary protein on gastrointestinal hormones and expression of an array of digestive enzymes in the gastrointestinal tract and pancreas. Results indicated that there were no significant differ- ences in expression of enzymes involved in carbohydrate digestion, except for maltase in the duodenum. In the je- junum, amylase expression in pigs fed 20% CP was much higher than that in pigs fed other diets (P〈0.05) and maltase expression in those fed 17% CP was higher than that in other treatments (P〈0.05). Although there were no remarkable differences in expression of aminopeptidase in the small intestine or carboxypeptidase in the pancreas (P〉0.05), there was a trend towards higher expression of various proteases in pigs fed 17% CP. The duodenal expression of en- teropeptidase in diets with 14% and 17% CP was significantly higher than that with 20% CP (P〈0.05), but treatment differences did not existed in jejunum (P〉0.05). The expression of GPR93 as a nutrient-responsive G protein-coupled receptor in 14% and 17% CP diets was significantly higher than that in 20% CP diet in the small intestine (P〈0.05). The expressions of genes for pancreatic enzymes, lipase and elastase, were significantly higher in pigs fed diets with low CP, while similar trends occurred for carboxypeptidase, chymotrypsin and amylase. Conversely, the gastric expres- sions of pepsinogen A and progastricsin were lower with the 17% CP diet. Differences between treatments were found in the gastric antral contents of cholecystokinin and somatostatin: both increased in pigs fed 17% CP, accompanied by decreased content of motilin, which was also seen in plasma concentrations. These patterns were not reflected in duodenal contents. In general, 17% dietary CP was beneficial to the digestion of nutrient substance in the gastroin- testinal tract.
基金supported by a grant from the Paralyzed Veterans Association (PVA # 2442)
文摘The axonal compartment of developing neurons and mature peripheral nervous system (PNS) neurons has the capacity to locally synthesize proteins. Axonally-synthesized proteins have been shown to facilitate axonal pathfinding and maintenance in developing central nervous system (CNS) and PNS neurons, and to facilitate the regeneration of mature PNS neurons. RNA-profiling studies of the axons of cultured neurons have shown a surprisingly complex population of mRNAs that encode proteins for a myriad of functions. Although classic-appearing rough endoplasmic reticulum (RER), smooth endoplasmic reticulum (ER) and Golgi apparatus have not been documented in axons by ultrastructural studies, axonal RNA profiling studies show several membrane and secreted protein-encoding mRNAs whose translation products would need access to a localized secretory mechanism. We previously showed that the axons of cultured neurons contain functional equivalents of RER and Golgi apparatus. Here, we show that markers for the signal-recognition particle, RER, ER, and Golgi apparatus are present in PNS axons in vivo. Co-localization of these proteins mirrors that seen for cultured axons where locally-translated proteins are localized to the axoplasmic membrane. Moreover, nerve injury increases the levels and/or aggregation of these proteins, suggesting that the regenerating axon has an increased capacity for membrane targeting of locally synthesized proteins.
基金Supported by Shenzhen Science and Technology Project(JCYJ20170818111629778,JCYJ20170306161613251)National Natural Science Foundation of Guangdong Province(2017A030313174)+2 种基金Natural Science Foundation of Guangdong Ocean University(C17379)Undergraduate Innovative and Entrepreneurial Team Project(CCTD201802)Science and Technology Program of Guangdong Province(2015A020209163)
文摘In this study, Va 1686 gene was cloned from Vibrio alginolyticus . The total length of the gene is 1 164 bp, and it could encode 387 amino acids. The physicochemical properties, protein structure, genetic evolutionary relationship and antigenic characteristics of the effect protein Va1686 of V. alginolyticus HY9901 type Ⅲ secretion system were studied and analyzed by bioinformatics methods and tools. The results showed that Va1686 is a stable hydrophilic and acidic protein without a transmembrane region and a signal peptide, and secondary structure to α-helix. The evolutionary analysis showed that V. alginolyticus HY9901 and V. harveyi were clustered together, which indicated that the genetic relationship between the two species was the closest. Va1686 contains a Fic superfamily conserved domain associated with cell division. Bioinformatics analysis showed that the B-cell preponderant epitopes of Va1686 might be localized in the regions of 48-49, 82-85, 125-126, 150-153, 185-186, 236-237 and so on. The 3D structure model of Va1686 subunit was simulated by SWISS-MODEL software and it was found that the vopS of V. parahaemolyticus was similar and the similarity was 89.46%. In this study, the feasibility of Va1686 as a common antigen of Vibrio was verified from the perspective of bioinformatics, which laid the foundation for the next step in vaccine development.
基金Supported by Grant from the National Natural Science Foundation of China,No. 30771039
文摘AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,which serve as a model for enteroendocrine L-cells,by quantitative reverse transcription-polymerase chain reaction and Western blotting before and after treatment with oleic acid.Localization of UCP2 and GLP-1 in NCI-H716 cells was assessed by immunofluorescence labeling.NCI-H716 cells were transiently transfected with a small interfering RNA(siRNA) that targets UCP2(siUCP2) or with a nonspecific siRNA using Lipofectamine 2000.The concentrations of bioactive GLP-1 in the medium were measured by enzyme linked immunosorbent assay.RESULTS:Both GLP-1 and UCP2 granules were expressed mainly in the cytoplasm of NCI-H716 cells.NCI-H716 cells that secreted GLP-1 also expressed UCP2.Time-course experiments revealed that release of GLP-1 from NCI-H716 cells into the medium reached a maximum at 120 min and remained stable until at least 180 min after treatment with oleic acid(the level of GLP-1 increased about 2.3-fold as compared with the level of GLP-1 in the control cells,P < 0.05).In an experiment to determine dose dependence,stimulation of NCI-H716 cells with ≤ 8 mmol oleic acid led to a concentration-dependent release of GLP-1 into the medium;10 mmol oleic acid diminished the release of GLP-1.Furthermore,GLP-1 secretion induced by oleic acid from NCI-H716 cells that were transfected with siUCP2 decreased to 41.8%,as compared with NCI-H716 cells that were transfected with a non-specific siRNA(P < 0.01).CONCLUSION:UCP2 affected GLP-1 secretion induced by oleic acid.UCP2 plays an important role in L-cell secretion that is induced by free fatty acids.
基金Supported by the Major State Basic Research Development Program (973 Program) of China, No.2003CB515507
文摘AIM: To examine the existence of Nitric oxide/ cGMP sensitive store-operated Ca^2+ entry in mouse fibroblast NIH/3T3 cells and its influence on matrix metalloproteinase (MMP) production and adhesion ability of fibroblasts. METHODS: NIH/3T3 cells were cultured. Confocal laser scanning microscopy was used to examine the existence of thapsigargin-induced store-operated Ca^2+ entry in fibroblasts. Gelatin zymography and semiquantitative reverse transcriptase-polymerase chain reaction (RTPCR) were employed to detect the involvement of [Ca^2+]i and NO/cGMP in MMP secretion. The involvement of NO/ cGMP-sensitive Ca^2+ entry in adhesion was determined using matrigel-coated culture plates. RESULTS: 8-bromo-cGMP inhibited the thapsigargin-induced Ca^2+ entry in 3T3 cells. The cGMP-induced inhibition was abolished by an inhibitor of protein kinase G, KT5823 (1μmol/L). A similar effect on the Ca^2+ entry was observed in 3T3 cells in response to a NO donor, (±)-S-nitroso-N-acetylpenicillamine (SNAP). The inhibitory effect of SNAP on the thapsigargin-induced Ca^2+ entry was also observed, indicating NO/cGMP-regulated Ca^2+ entry in 3T3 cells. Results of gelatin zymography assay showed that addition of extracellular Ca^2+ concentration induced MMP release and activation in a dose-dependent manner. RT-PCR also showed that cGMP and SNAP reduced the production of MMP mRNA in 3T3 cells. Experiments investigating adhesion potentials demonstrated that cGMP and SNAP could upgrade 3T3 cell attachment rate to the matrigel-coated culture plates.CONCLUSION: NO/cGMP sensitive store-operated Ca^2+ entry occurs in fibroblasts, and attenuates their adhesion potentials through its influence on MMP secretion.
基金This work was supported by Natural Science Foundationof Hunan Province (No. 06JJ4108)the Hygienic Committee of Hunan Province (No. B2005-084).
文摘Objective: To provide the experimental basis for further studying the molecular transformation mechanism of Hepatitis B virus (HBV) X protein (HBx) on hepatocellular carcinoma. Methods: Reconstructed plasmid pcDNA3.1(+)-HBx was transfected into THP-1 macrophages. Expression of HBx was assayed in macrophages lysate by Western-blotting, and TNF-α and IL-1β contents were detected respectively by ELISA. All the data were analyzed by SPSS13.0. Results: In THP-lmacrophages, the pcDNA3.1(+)-HBx plasmid expressed HBx with a molecular weight of about 17 KDa demonstrated by Western-blotting. The secreted TNF-α and IL-1β from macrophages were determined by ELISA, the results from analysis of all groups showed as following: control group was different from LPS group and pcDNA3.1(+) group (P〈0.01), and so was pcDNA3.1(+)-HBx group; but there was no obvious difference between pcDNA3.1(+) group and LPS group (P〉0.05), all of which indicated that transient overexpression of HBx enhanced LPS-induced production of TNF-α and IL-1β by macrophages. Conclusion: Transient overexpression of HBx up-regulates LPS-induced TNF-t~ and IL-113 secretion of macrophages.
基金supported by the National Natural Science Foundation of China(30260079)the Key Project of the Natural Science Foundation of Yunnan Province,China(2000C0005Z)
文摘The present study was to investigate the effect of monoclonal antibody against porcine 40-kDa adipocyte-specific membrane protein on endocrine secretion in pigs, in order to provide the evidence for application of this antibody to reduce excessive fat deposition in pig production. 40 Landrace×Saba pigs were randomly divided into 8 groups: 2 control groups were given saline with 10 mL, respectively, and the 6 treatment groups were given monoclonal antibody against porcine 40-kDa adipocyte-specific membrane protein with 0.1, 0.5, and 1.0 mg ·kg^-1 body weight at 15 or 60 kg body weight, respectively, all treatments were performed by intraperitoneal injection. The results showed that this monoclonal antibody could significantly reduce serum insulin level and increase levels of serum growth hormone (GH), insulin-like growth factor-1(IGF-1), triiodothyronine (T3), and tetraiodothyronine (T4) either at 15 or 60 kg body weight injection. However, more marked effect was observed at 15 kg body weight treatment. Moreover, the dose-dependent effect of this monoclonal antibody on endocrine secretion was also observed. This result revealed that this monoclonal antibody increased secretion of hormones regulating fat lysis and reduced secretion of hormones regulating fat synthesis, suggests the reduction of porcine excessive fat deposition by this monoclonal antibody was carried out through affecting hormones regulating fat metabolism.
基金Supported by a grant from the Korean Ministry of Science and Technology (Korean Systems Biology Research Grant, M1-0309-06-0002) partly by the research grant from Hallym University, Korea Co-first-authors: Kyu-Jin Park
文摘AIM: We have previously demonstrated that hepatitis C virus (HCV) core protein is efficiently released into the culture medium in insect cells. The objective of this study is to characterize the HCV core secretion in insect cells. METHODS: We constructed recombinant baculoviruses expressing various-length of mutant core proteins, expressed these proteins in insect cells, and examined core protein secretion in insect cells. RESULTS: Only wild type core was efficiently released into the culture medium, although the protein expression level of wild type core was lower than those of other mutant core proteins. We found that the shorter form of the core construct expressed the higher level of protein. However, if more than 18 amino acids of the core were truncated at the C-terminus, core proteins were no longer secreted into the culture medium. Membrane flotation data show that the secreted core proteins are associated with the cellular membrane protein, indicating that HCV core is secreted as a membrane complex. CONCLUSION: The C-terminal 18 amino acids of HCV core were crucial for core secretion into the culture media. Since HCV replication occurs on lipid raft membrane structure, these results suggest that HCV may utilize a unique core release mechanism to escape immune surveillance, thereby potentially representing the feature of HCV morphogenesis.
文摘Ma et al recently reported in the World Journal of Diabetes that ferroptosis occurs in osteoblasts under high glucose conditions,reflecting diabetes pathology.This condition could be protected by the upregulation of the gene encoding polycytosine RNA-binding protein 1(PCBP1).Additionally,Ma et al used a lentivirus infection system to express PCBP1.As the authors’method of administration can be improved in terms of stability and cost,we propose delivering PCBP1 to treat type 2 diabetic osteoporosis by encapsulating it in protein nanoparticles.First,PCBP1 is small and druggable.Second,intravenous injection can help deliver PCBP1 across the mucosa while avoiding acid and enzyme-catalyzed degradation.Furthermore,incorporating PCBP1 into nanoparticles prevents its interaction with water or oxygen and protects PCBP1’s structure and activity.Notably,the safety of the protein materials and the industrialization techniques for large-scale production of protein nanoparticles must be comprehensively investigated before clinical application.
基金Supported by Shenzhen Science and Technology Project(JCYJ20170818111629778,JCYJ20170306161613251)National Natural Science Foundation of Guangdong Province(2017A030313174)+1 种基金Natural Science Foundation of Guangdong Ocean University(C17379)Undergraduate Innovative and Entrepreneurial Team Project(CCTD201802)
文摘In this study,Hy322 gene was cloned from Vibrio alginolyticus.The total length of its gene was 969 bp,and it could encode 322 amino acids.The physicochemical properties,protein structure,genetic evolutionary relationship and antigenic characteristics of the effector protein Hy322 of V.alginolyticus HY9901 type Ⅲ secretion system were studied and analyzed by bioinformatics methods and tools.The results showed that Hy322 is an unstable hydrophilic and acidic protein without a transmembrane region and a signal peptide,and secondary structure to α-helix.The evolutionary analysis showed that V.alginolyticus HY9901 and V.harveyi were clustered together,which indicated that the genetic relationship between the two species was closest.HY322 contains a FliN super family conserved domain associated with Flagellar motor switch.Bioinformatics analysis showed that the B-cell preponderant epitopes of Hy322 might be localized in the regions of 32-33,100-102,138-140,215-216,235-238 and 246-249.The 3D structure model of Hy322 subunit was simulated by SWISS-MODEL software and itwas found that the yscQ of Yersinia were similar and the similarity was 42.25%.In this study,the feasibility of Hy322 as a common antigen of Vibrio was verified from the perspective of bioinformatics,which laid the foundation for the next step in vaccine development.
文摘In this study the effect of human recombinant interferon gamma hrIFN-γ)on hCG secretion of human first trimester trophoblast and protein synthesis of decidual tissue was investigated in vitro.The results indicated that hrIFN-γat the doses of 250 U/ml medium and 2500 U/ml medium decreased hCG secretion of trophoblast obviously(P<0.05, P<0.01)in a dose dependent manner.The effect of hrIFN-γon protein synthesis at the doses of 10 U to 1,000 U/ml medium inhibited the 3H leucine incorporation obviously.The cpm values between control and experimental groups were significantly different(P<0. 05) in a dosedependent manner.Furthermore its inhibitory effect is in a dose-dependent manner and was neutralized by IFN-γantiserum.The IFN-a at the doses used did not find any effect on protein synthesis in decidual tissue.