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1.
Neuroreport ; 34(18): 853-859, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-37942736

ABSTRACT

The interaction between the µ opioid receptor (MOR) and ß-arrestin2 serves as a model for addressing morphine tolerance. A peptide was designed to alleviate morphine tolerance through interfering with the interaction of MOR and ß-arrestin2. We developed a peptide derived from MOR. The MOR-TAT-pep peptide was expressed in E. coli Bl21(DE3) and purified. The effects of MOR-TAT-pep in alleviating morphine tolerance was examined through behavior tests. The potential mechanism was detected by Western blotting, Mammalian Two-Hybrid and other techniques. The pretreatment with MOR-TAT-pep prior to morphine usage led to an enhanced analgesic effectiveness of morphine and a significant reduction in the development of morphine tolerance. The peptide directly interacted with ß-arrestin2 during morphine treatment and deceased the membrane recruitment of ß-arrestin2. MOR-TAT-pep effectively suppressed the increase of ß-arrestin2 induced by morphine. The MOR-TAT-pep could alleviate morphine tolerance through inhibition of ß-arrestin2.


Subject(s)
Analgesics, Opioid , Morphine , Animals , Morphine/pharmacology , Analgesics, Opioid/pharmacology , beta-Arrestin 1 , Receptors, Opioid, mu/metabolism , Escherichia coli/metabolism , Peptides , Mammals/metabolism
2.
Front Chem ; 11: 1273674, 2023.
Article in English | MEDLINE | ID: mdl-37841209

ABSTRACT

Introduction: Biomimetic lubricant-infused porous surfaces are developed and applied for omniphobicity and corrosion protection, which exhibit great advantages compared to superhydrophobic surfaces. Methods: Herein, superhydrophobic Fe@E-Zn@PFOA was prepared via the electrodeposition of laminated Zinc coating, further vapor etching, and post-modification with perfluoro caprylic acid. The facile, inexpensive, and environment-friendly water vapor etching process can form a porous honeycomb-like structure. Moreover, the perfluoropolyether lubricant was wicked into the porous and superhydrophobic surfaces, obtaining lubricant-infused surfaces of Fe@E-Zn@PFOA@PFPE. Results and discussion: The influences of the textured roughness and chemical composition on the surface wettability were systematically investigated. The Fe@E-Zn@PFOA@PFPE performs omniphobicity with small sliding angles and superior corrosion resistance compared with the superhydrophobic surface, owing to their multiple barriers, including infused lubricant, hydrophobic monolayers, and compact Zn electroplating coating. Thus, the proposed lubricant-infused surface may provide insights into constructing protective coatings for the potential applications of engineering metal materials.

3.
Front Microbiol ; 14: 1239537, 2023.
Article in English | MEDLINE | ID: mdl-37808302

ABSTRACT

Lipopolysaccharide (LPS) is essential for most gram-negative bacteria and plays an important role in serum resistance, pathogenesis, drug resistance, and protection from harsh environments. The outer core oligosaccharide of LPS is involved in bacterial recognition and invasion of host cells. The D-galactosyltransferase WaaB is responsible for the addition of D-galactose to the outer core oligosaccharide of LPS, which is essential for Salmonella typhimurium invasion. Here we report the first crystal structures of WaaB and WaaB in complex with UDP to resolutions of 1.8 and 1.9 Å, respectively. Mutagenesis and enzyme activity assays confirmed that residues V186, K195, I216, W243, E276, and E269 of WaaB are essential for the binding and hydrolysis of UDP-galactose. The elucidation of the catalytic mechanism of WaaB is of great importance and could potentially be used for the design of novel therapeutic reagents.

4.
Am J Transl Res ; 15(7): 4467-4486, 2023.
Article in English | MEDLINE | ID: mdl-37560210

ABSTRACT

Wound infection remains a major challenge for health professionals, because it delays wound healing and increases the overall cost and morbidity. Therefore, the development of new biomaterials with new antibacterial properties and healing effects remains a dire clinical need. To solve this problem, we developed silver nanoparticles embedded in γ-cyclodextrin metal-organic frameworks (Ag@MOF) and platelet-rich plasma (PRP)-loaded hydrogel systems based on methacrylated silk fibroin (SFMA) and methacrylate hyaluronic acid (HAMA) as Ag+ ion and growth factor delivery vehicles for inhibiting the growth of drug-resistant bacteria and promoting wound healing. The prepared SFMA/HAMA hydrogel demonstrated good rheological properties, swelling capability, appropriate mechanical properties and controllable biodegradability. The SFMA/HAMA/Ag@MOF/PRP hydrogel showed sustained release profiles of Ag+ ions and EGF. The SFMA/HAMA/Ag@MOF hydrogel have good inherent antibacterial properties against both gram-negative bacteria and gram-positive bacteria. The prepared hydrogel showed excellent cytocompatibility and could stimulate the growth and proliferation rate of NIH-3T3 cells. In vivo experiments showed that SFMA/HAMA/Ag@MOF/PRP hydrogel treatment enhanced the healing of full-thickness wounds, reduced inflammatory cell infiltration, and promoted re-epithelialization and collagen synthesis. All results indicated that the prepared hydrogel has tremendous potential to reduce wound infections and improve wound healing.

5.
Plast Reconstr Surg ; 2023 May 22.
Article in English | MEDLINE | ID: mdl-37220233

ABSTRACT

BACKGROUND: The fat repositioning technique has been widely used for the treatment of tear trough deformity, and there is a strong belief that excess fat herniation is a prerequisite for the procedure. OBJECTIVE: The purpose of this study was to evaluate its effect in patients with minimal or no excess fat herniation. METHODS: A total of 232 patients underwent the procedure and met the inclusion criteria. Of them, 198 were primary cases, and 34 had a history of fat removal for blepharoplasty. The amount of infraorbital fat was evaluated preoperatively by palpation. Release of the tear trough ligament and fat redistribution were sequentially performed as previously described. Surgical outcome was assessed based on Hirmand's grading system and the FACE-Q scales. RESULTS: Tear trough deformities were eliminated in more than 85% of cases. Aesthetic results were comparable between the primary and secondary surgery groups. The percentage of patients who complained of extremely or moderately severe tear trough deformities decreased from 86.3% preoperatively to 34.0% postoperatively. The scores of the lower eyelid FACE-Q decreased significantly (P<0.05). Patients were satisfied with their decision to undergo blepharoplasty (78.2±18.7). Undercorrection of the tear trough occurred in 30 patients. Other complications included 12 cases of transient conjunctiva bleeding, 2 cases of eyelid numbness, and 6 cases of dry eye. These resolved spontaneously. CONCLUSION: Fat repositioning is a feasible and effective technique for the treatment of tear trough deformities in patients with minimal or no excess orbital fat herniation provided that a fat pad is palpable. LEVEL OF EVIDENCE: 4.

6.
J Nanobiotechnology ; 21(1): 119, 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-37020301

ABSTRACT

BACKGROUND: Sustained release of bioactive BMP2 (bone morphogenetic protein-2) is important for bone regeneration, while the intrinsic short half-life of BMP2 at protein level cannot meet the clinical need. In this study, we aimed to design Bmp2 mRNA-enriched engineered exosomes, which were then loaded into specific hydrogel to achieve sustained release for more efficient and safe bone regeneration. RESULTS: Bmp2 mRNA was enriched into exosomes by selective inhibition of translation in donor cells, in which NoBody (non-annotated P-body dissociating polypeptide, a protein that inhibits mRNA translation) and modified engineered BMP2 plasmids were co-transfected. The derived exosomes were named ExoBMP2+NoBody. In vitro experiments confirmed that ExoBMP2+NoBody had higher abundance of Bmp2 mRNA and thus stronger osteogenic induction capacity. When loaded into GelMA hydrogel via ally-L-glycine modified CP05 linker, the exosomes could be slowly released and thus ensure prolonged effect of BMP2 when endocytosed by the recipient cells. In the in vivo calvarial defect model, ExoBMP2+NoBody-loaded GelMA displayed great capacity in promoting bone regeneration. CONCLUSIONS: Together, the proposed ExoBMP2+NoBody-loaded GelMA can provide an efficient and innovative strategy for bone regeneration.


Subject(s)
Exosomes , Hydrogels , Bone Regeneration , Delayed-Action Preparations/metabolism , Exosomes/metabolism , Hydrogels/pharmacology , Osteogenesis , RNA, Messenger/metabolism , Bone Morphogenetic Protein 2/metabolism
7.
Int J Nanomedicine ; 17: 3793-3807, 2022.
Article in English | MEDLINE | ID: mdl-36072958

ABSTRACT

Purpose: Forming a compact biological seal between the gingiva and the implant interface around the percutaneous parts of an implant is one of the key issues in preventing peri-implantitis. Methods: In this study, since microRNA-21 (miR-21) has been approved to promote fibroblast proliferation and collagen formation in skin fibrosis, we prepared miR-21-loaded chitosan (CS)/tripolyphosphate (TPP)/hyaluronic acid (HA) nanoparticles (CTH NPs) and cross-linked them to smooth Ti surfaces with 0.2% gel solution for reverse transfection, after which isolated human gingival fibroblasts were cultured on the miR-21-functionalized Ti substrates. Results: An optimal CS:TPP:HA ratio (1:0.15:0.1) and N/P ratio (20:1) were chosen to produce appropriate nanoparticles. Finally, the CTH/miR-21 nanoparticle-coated smooth Ti surfaces demonstrated increased fibroblast adhesion, proliferation and expression of extracellular matrix-related genes along with similar cytotoxicity and cell spreading on the miR-21-functionalized Ti surface and the unmodified smooth Ti surface. Conclusion: The chitosan-based nanoparticles might be an efficient nonviral miRNA vector to form a stable biological seal in percutaneous areas of Ti for clinical use.


Subject(s)
Chitosan , MicroRNAs , Nanoparticles , Fibroblasts , Gingiva/metabolism , Humans , Hyaluronic Acid/pharmacology , MicroRNAs/genetics , MicroRNAs/metabolism , Surface Properties , Titanium/pharmacology
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(2): 122-127, 2020 Apr 01.
Article in Chinese | MEDLINE | ID: mdl-32314882

ABSTRACT

OBJECTIVE: This study aimed to evaluate the effects of porcine acellular cartilaginous matrix (pACM) on the proliferation and differentiation of human adipose-derived stromal cells (hADSCs). METHODS: pACM was prepared from porcine articular cartilage through decellularization treatment. hADSCs were isolated from human adipose tissues and cultured with different pACM concentrations. No pACM was used as the control group. The effect of pACM on hADSCs proliferation was detected by CCK-8 method. Moreover, the effect of pACM on hADSCs chondrogenic differentiation was analyzed through fluorescence quantitative polymerase chain reaction and Western blot. RESULTS: hADSCs proliferation rate in 0.5, 1.0, and 2.0 mg·mL⁻¹ pACM groups was not significantly different from that in the control group, whereas that in 4.0 and 8.0 mg·mL⁻¹ pACM group was lower than that in the control group (P<0.05). The expression levels of pACM chondrogenic genes, including SOX-9, collagen type Ⅱ alpha 1 chain (COL2A1), and aggrecan (ACAN) and cell adhesion-related gene LAMININ in 0.5, 1.0, and 2.0 mg·mL⁻¹ pACM group were higher than those of the control group (P<0.05), but that of a stemness-related gene Notch-1 was lower than that of the control group (P<0.05). No statistical difference was found in the expression of a lipogenesis-related gene peroxisome proliferator-activated receptor-γ (PPAr-γ) (P>0.05). The expression levels of chondrogenic proteins (SOX-9, COL2A1, and ACAN) were higher than those of the control group (P<0.05). CONCLUSIONS: Appropriate pACM con-centrations do not affect hADSCs proliferation but can induce hADSCs chondrogenic differentiation.


Subject(s)
Adipocytes , Stem Cells , Adipose Tissue , Animals , Cell Differentiation , Cell Proliferation , Cells, Cultured , Chondrogenesis , Humans , Stromal Cells , Swine
9.
Biomed Res Int ; 2018: 3429569, 2018.
Article in English | MEDLINE | ID: mdl-30515393

ABSTRACT

OBJECTIVES: To purify and characterize the glutathione binding protein GsiB of glutathione importer (GSI) in Escherichia coli (E. coli). RESULTS: The coding sequence of GsiB was cloned from E. coli MG1655 and expressed in BL21(DE3). GsiB protein was expressed and purified to homogeneity using Ni-affinity and gel filtration chromatography. SDS-PAGE of purified GsiB showed a single protein band of molecular mass 56 kDa, while native gel showed two bands around 56 kDa and 110 kDa. Gene knockout showed that GsiB was essential for GSI mediated glutathione import. Interactions of GsiA, B, C, and D were determined using bacterial two-hybrid method. Without glutathione, GsiB showed no direct interaction with the other three proteins. However, GsiB could interact with GsiC and GsiD when using glutathione as sole sulfur source. CONCLUSIONS: GsiB functions in E. coli was characterized which could help elucidate the glutathione import mechanism in gram-negative bacteria.


Subject(s)
Escherichia coli Proteins/isolation & purification , Escherichia coli/genetics , Glutathione/chemistry , Membrane Transport Proteins/isolation & purification , Chromatography, Gel , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Gene Expression Regulation, Bacterial/genetics , Glutathione/genetics , Membrane Transport Proteins/chemistry , Membrane Transport Proteins/genetics , Protein Binding
10.
Carbohydr Polym ; 182: 215-224, 2018 Feb 15.
Article in English | MEDLINE | ID: mdl-29279118

ABSTRACT

Bone regeneration involves complex physiological processes, which is generally regulated and controlled by multiple bioactive molecules. In situ controlled release of combined bioactive factors in a spatiotemporal sequence for adapting the demand of bone regeneration is a desired strategy. In this study, nanoparticle/hydrogel composite system was constructed by incorporating stromal cell derived factor-1α (SDF-1α) and chitosan/tripolyphosphate/hyaluronic acid/antimiRNA-138 nanoparticles (CTH/antimiR-138 NPs) in chitosan/ß-sodium glycerol phosphate (CS/GP) hydrogel for rat critical-size calvarial bone regeneration. The fast release of SDF-1α promoted the migration of mesenchymal stem cells (MSCs) for 6 d, while the sustained release of antimiR-138 from the nanoparticle/hydrogel compound enhanced the osteogenic differentiation of MSCs over 21 d. 8 weeks after surgery, calvarial specimens were evaluated by microcomputed tomography (µ-CT), histological analysis and immunohistochemistry. Comparing with blank group and hydrogel group, hydrogels incorporated with SDF-1α and/or CTH/antimiR-138 NPs significantly enhanced bone regeneration (p<0.05). In addition, the expression of collagen type-1 (COL-1), osteopontin (OPN) and osteocalcin (OCN) proteins were enhanced in the combined drug group (incorporated both SDF-1α and CTH/antimiR-138 NPs) in comparison to the hydrogel group. Our research indicated the in situ formation of NPs/hydrogel composite could provide temporal sequence-release of SDF-1α and CTH/antimiR-138 NPs for on-demand MSCs homing and cranial bone regeneration.


Subject(s)
Bone Regeneration , Chemokine CXCL12/chemistry , Oligonucleotides/chemistry , Animals , Bone Regeneration/drug effects , Cell Differentiation/drug effects , Cell Movement/drug effects , Chemokine CXCL12/pharmacology , Chitosan/chemistry , Hyaluronic Acid/chemistry , Hydrogel, Polyethylene Glycol Dimethacrylate/chemistry , Male , Mesenchymal Stem Cells/drug effects , Nanoparticles/chemistry , Oligonucleotides/pharmacology , Polyphosphates/chemistry , Rats , Rats, Sprague-Dawley
11.
Biochem J ; 474(23): 3951-3961, 2017 11 21.
Article in English | MEDLINE | ID: mdl-28974626

ABSTRACT

Outer membrane (OM) ß-barrel proteins play important roles in importing nutrients, exporting wastes and conducting signals in Gram-negative bacteria, mitochondria and chloroplasts. The outer membrane proteins (OMPs) are inserted and assembled into the OM by OMP85 family proteins. In Escherichia coli, the ß-barrel assembly machinery (BAM) contains four lipoproteins such as BamB, BamC, BamD and BamE, and one OMP BamA, forming a 'top hat'-like structure. Structural and functional studies of the E. coli BAM machinery have revealed that the rotation of periplasmic ring may trigger the barrel ß1C-ß6C scissor-like movement that promote the unfolded OMP insertion without using ATP. Here, we report the BamA C-terminal barrel structure of Salmonella enterica Typhimurium str. LT2 and functional assays, which reveal that the BamA's C-terminal residue Trp, the ß16C strand of the barrel and the periplasmic turns are critical for the functionality of BamA. These findings indicate that the unique ß16C strand and the periplasmic turns of BamA are important for the outer membrane insertion and assembly. The periplasmic turns might mediate the rotation of the periplasmic ring to the scissor-like movement of BamA ß1C-ß6C, triggering the OMP insertion. These results are important for understanding the OMP insertion in Gram-negative bacteria, as well as in mitochondria and chloroplasts.


Subject(s)
Bacterial Outer Membrane Proteins/chemistry , Escherichia coli Proteins/chemistry , Escherichia coli/metabolism , Periplasm/metabolism , Plasmids/chemistry , Salmonella typhimurium/metabolism , Amino Acid Motifs , Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Cloning, Molecular , Crystallography, X-Ray , Escherichia coli/genetics , Escherichia coli/ultrastructure , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Gene Expression , Models, Molecular , Mutation , Periplasm/genetics , Periplasm/ultrastructure , Plasmids/metabolism , Protein Binding , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Salmonella typhimurium/genetics , Salmonella typhimurium/ultrastructure
12.
Biomed Res Int ; 2017: 3076091, 2017.
Article in English | MEDLINE | ID: mdl-28691022

ABSTRACT

The coding sequence of Salmonella enterica gsiA was cloned and expressed in E. coli. The protein was purified and ATPase activity was characterized by NADH oxidation method. GsiA exhibited optimum activity at 30°C and at pH 8 in Tris/HCl buffer. GsiA protein was stable at 20°C. 66% and 44% activity remained after incubation at 30°C and 40°C for 30 min. pH 7 and pH 9 incubation would obviously reduce the ATPase activity. In vivo functionality of gsiA was determined by constructing gene deletion strains. gsiA was shown to be essential for GSI mediated glutathione uptake and gsiA deletion could decrease the virulence of Salmonella enterica. Interactions of glutathione import proteins GsiA, GsiB, GsiC, and GsiD were investigated by using bacterial two-hybrid system. GsiA could interact with itself and inner membrane proteins GsiC and GsiD. This report provides the first description of gsiA functions in Salmonella enterica. The results could help elucidating the glutathione uptake mechanism and glutathione functions in bacteria.


Subject(s)
Adenosine Triphosphatases/isolation & purification , Adenosine Triphosphatases/metabolism , Bacterial Proteins/isolation & purification , Bacterial Proteins/metabolism , Salmonella enterica/enzymology , Animals , Glutathione/metabolism , Male , Mice , NAD/metabolism , Oxidation-Reduction , Protein Binding , Salmonella enterica/growth & development , Salmonella enterica/pathogenicity
13.
Sci Rep ; 7(1): 3038, 2017 06 08.
Article in English | MEDLINE | ID: mdl-28596582

ABSTRACT

Irradiated bone has a greater risk of implant failure than nonirradiated bone. The purpose of this study was to investigate the influence of cell sheets composed of co-cultured bone marrow mesenchymal stromal cells (BMSCs) and endothelial progenitor cells (EPCs) on implant osseointegration in irradiated bone. Cell sheets (EPCs, BMSCs or co-cultured EPCs and BMSCs) were wrapped around titanium implants to make cell sheet-implant complexes. The co-cultured group showed the highest osteogenic differentiation potential in vitro, as indicated by the extracellular matrix mineralization and the expression of osteogenesis related genes at both mRNA and protein levels. The co-cultured cells promoted ectopic bone formation as indicated by micro-computed tomography (Micro-CT) and histological analysis. In the irradiated tibias of rats, implants of the co-cultured group showed enhanced osseointegration by Micro-CT evaluation and histological observation. Co-cultured EPCs and BMSCs also up-regulated the expression of osteogenesis related genes in bone fragments in close contact with implants. In conclusion, cell sheets of co-cultured EPCs and BMSCs could promote osseous healing around implants and are potentially useful to improve osseointegration process for patients after radiotherapy.


Subject(s)
Endothelial Progenitor Cells/cytology , Endothelial Progenitor Cells/metabolism , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Osseointegration , Animals , Biomarkers , Bone Development/radiation effects , Bone and Bones/radiation effects , Coculture Techniques , Gene Expression , Immunophenotyping , Osteogenesis/genetics , Rats
14.
PLoS One ; 11(8): e0160860, 2016.
Article in English | MEDLINE | ID: mdl-27508931

ABSTRACT

IκBßis an inhibitor of nuclear factor kappa B(NF-κB) and participates in the cardiac response to sepsis. However, the role of the hypo-phosphorylated form of IκBß at Ser313, which can be detected during sepsis, is unknown. Here, we examined the effects of IκBß with a mutation at Ser313→Ala313 on cardiac damage induced by sepsis. Transgenic (Tg) mice were generated to overexpress IκBß, in which Ser-313 is replaced with alanine ubiquitously, in order to mimic the hypo-phosphorylated form of IκBß. Survival analysis showed that Tg mice exhibited decreased inflammatory cytokine levels and decreased rates of mortality in comparison to wild type (WT) mice, after sepsis in a cecal-ligation and puncture model (CLP). Compared to WT septic mice, sepsis in Tg mice resulted in improved cardiac functions, lower levels of troponin I and decreased rates of cardiomyocyte apoptosis, compared to WT mice. The increased formation of autophagicvacuoles detected with electron microscopy demonstrated the enhancement of cardiac autophagy. This phenomenon was further confirmed by the differential expression of genes related to autophagy, such as LC3, Atg5, Beclin-1, and p62. The increased expression of Cathepsin L(Ctsl), a specific marker for mitochondrial stress response, may be associated with the beneficial effects of the hypo-phosphorylated form of IκBß. Our observations suggest that the hypo-phosphorylated form of IκBß at Ser313 is beneficial to the heart in sepsis through inhibition of apoptosisand enhancement of autophagy in mutated IκBß transgenic mice.


Subject(s)
Heart/physiopathology , I-kappa B Proteins/metabolism , Sepsis/metabolism , Sepsis/physiopathology , Animals , Apoptosis/physiology , Autophagy/genetics , Cathepsin L/genetics , Cathepsin L/metabolism , Cytokines/genetics , Cytokines/metabolism , Gene Expression , I-kappa B Proteins/genetics , Male , Mice, Transgenic , Myocardium/cytology , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Phosphorylation , Sepsis/mortality , Serine/metabolism
15.
Sci Rep ; 6: 28126, 2016 06 21.
Article in English | MEDLINE | ID: mdl-27324079

ABSTRACT

Periodontal regeneration involves the restoration of at least three unique tissues: cementum, periodontal ligament tissue (PDL) and alveolar bone tissue. Here, we first isolated human PDL stem cells (PDLSCs) and jaw bone mesenchymal stem cells (JBMSCs). These cells were then induced to form cell sheets using an ascorbic acid-rich approach, and the cell sheet properties, including morphology, thickness and gene expression profile, were compared. Platelet-rich fibrin (PRF) derived from human venous blood was then fabricated into bioabsorbable fibrin scaffolds containing various growth factors. Finally, the in vivo potential of a cell-material construct based on PDLSC sheets, PRF scaffolds and JBMSC sheets to form periodontal tissue was assessed in a nude mouse model. In this model, PDLSC sheet/PRF/JBMSC sheet composites were placed in a simulated periodontal space comprising human treated dentin matrix (TDM) and hydroxyapatite (HA)/tricalcium phosphate (TCP) frameworks. Eight weeks after implantation, the PDLSC sheets tended to develop into PDL-like tissues, while the JBMSC sheets tended to produce predominantly bone-like tissues. In addition, the PDLSC sheet/PRF/JBMSC sheet composites generated periodontal tissue-like structures containing PDL- and bone-like tissues. Further improvements in this cell transplantation design may have the potential to provide an effective approach for future periodontal tissue regeneration.


Subject(s)
Guided Tissue Regeneration, Periodontal , Mandible/surgery , Maxilla/surgery , Mesenchymal Stem Cell Transplantation , Periodontal Ligament/surgery , Periodontitis/therapy , Platelet-Rich Fibrin/metabolism , Adolescent , Adult , Animals , Calcium Phosphates , Cell Differentiation , Cells, Cultured , Dentin , Humans , Male , Mandible/physiology , Maxilla/physiology , Mesenchymal Stem Cells/cytology , Mice , Mice, Nude , Osteogenesis , Periodontal Ligament/physiology , Periodontitis/surgery , Tissue Engineering , Tissue Scaffolds/chemistry , Young Adult
16.
Int J Nanomedicine ; 11: 2091-105, 2016.
Article in English | MEDLINE | ID: mdl-27274237

ABSTRACT

Cell sheet engineering has emerged as a novel approach to effectively deliver seeding cells for tissue regeneration, and developing human bone marrow mesenchymal stem cell (hBMMSC) sheets with high osteogenic ability is a constant requirement from clinics for faster and higher-quality bone formation. In this work, we fabricated biocompatible and safe chitosan (CS)/hyaluronic acid (HA) nanoparticles (NPs) to deliver microRNA-21 (miR-21), which has been proved to accelerate osteogenesis in hBMMSCs; then, the CS/HA/miR-21 NPs were cross-linked onto the surfaces of culture plates with 0.2% gel solution to fabricate miR-21-functionalized culture plates for reverse transfection. hBMMSC sheets were induced continuously for 14 days using a vitamin C-rich method on the miR-21-functionalized culture plates. For the characterization of CS/HA/miR-21 NPs, the particle size, zeta potential, surface morphology, and gel retardation were sequentially investigated. Then, the biological effects of hBMMSC sheets on the miR-21-functionalized culture plates were evaluated. The assay results demonstrated that the hBMMSC sheets could be successfully induced via the novel reverse transfection approach, and miR-21 delivery significantly enhanced the in vitro osteogenic differentiation of hBMMSC sheets in terms of upregulating calcification-related gene expression and enhancing alkaline phosphatase production, collagen secretion, and mineralized nodule formation. The enhanced osteogenic activity of hBMMSC sheets might promisingly lead to more rapid and more robust bone regeneration for clinical use.


Subject(s)
Mesenchymal Stem Cells/physiology , MicroRNAs/genetics , Nanoparticles/chemistry , Osteogenesis , Transfection/methods , Adult , Alkaline Phosphatase/metabolism , Cell Differentiation/genetics , Cells, Cultured , Chitosan/chemistry , Collagen/metabolism , Humans , Hyaluronic Acid/chemistry , Mesenchymal Stem Cells/cytology , MicroRNAs/metabolism , Osteogenesis/genetics , Static Electricity , Transgenes
17.
Colloids Surf B Biointerfaces ; 141: 102-111, 2016 May 01.
Article in English | MEDLINE | ID: mdl-26844646

ABSTRACT

Numerous preclinical and clinical studies have focused on the periodontal regenerative functions of enamel matrix derivative (EMD), a heat-treated preparation derived from enamel matrix proteins (EMPs) of developing porcine teeth. In this study, periodontal ligament (PDL) stem cells (PDLSCs) were isolated, and the effects of EMD on the extracorporeal induction process and the characteristics of PDLSC sheets were investigated for their potential as a more effective stem-cell therapy. EMD-enhanced cell sheets could be induced by complete medium supplemented with 50 µg/mL vitamin C and 100 µg/mL EMD. The EMD-enhanced cell sheets appeared thicker and more compact than the normal PDLSC sheets, demonstrated more layers of cells (3-7 layers), secreted richer extracellular matrix (ECM), showed varying degrees of increases in mRNA expression of periodontal tissue-specific genes (COL I, POSTN), calcification-related genes (RUNX2, OPN, OCN) and a cementum tissue-specific gene (CAP), and possessed a better mineralization ability in terms of osteogenic differentiation in vitro. These EMD-enhanced cell sheets may represent a potential option for stem-cell therapy for PDL regeneration.


Subject(s)
Cell Proliferation/drug effects , Dental Enamel Proteins/pharmacology , Periodontal Ligament/cytology , Stem Cells/drug effects , Adipogenesis/drug effects , Adult , Animals , Ascorbic Acid/pharmacology , Cell Adhesion Molecules/genetics , Cell Differentiation/drug effects , Cell Survival/drug effects , Cells, Cultured , Collagen Type I/genetics , Collagen Type I/metabolism , Gene Expression/drug effects , Humans , Immunohistochemistry , Microscopy, Electron, Scanning , Osteogenesis/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Stem Cells/metabolism , Stem Cells/ultrastructure , Swine , Vitamins/pharmacology , Young Adult
18.
Nature ; 531(7592): 64-9, 2016 Mar 03.
Article in English | MEDLINE | ID: mdl-26901871

ABSTRACT

All Gram-negative bacteria, mitochondria and chloroplasts have outer membrane proteins (OMPs) that perform many fundamental biological processes. The OMPs in Gram-negative bacteria are inserted and folded into the outer membrane by the ß-barrel assembly machinery (BAM). The mechanism involved is poorly understood, owing to the absence of a structure of the entire BAM complex. Here we report two crystal structures of the Escherichia coli BAM complex in two distinct states: an inward-open state and a lateral-open state. Our structures reveal that the five polypeptide transport-associated domains of BamA form a ring architecture with four associated lipoproteins, BamB-BamE, in the periplasm. Our structural, functional studies and molecular dynamics simulations indicate that these subunits rotate with respect to the integral membrane ß-barrel of BamA to induce movement of the ß-strands of the barrel and promote insertion of the nascent OMP.


Subject(s)
Bacterial Outer Membrane Proteins/chemistry , Bacterial Outer Membrane Proteins/metabolism , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/metabolism , Escherichia coli/chemistry , Multiprotein Complexes/chemistry , Multiprotein Complexes/metabolism , Crystallography, X-Ray , Lipoproteins/chemistry , Lipoproteins/metabolism , Models, Molecular , Molecular Dynamics Simulation , Movement , Periplasm/metabolism , Protein Binding , Protein Structure, Tertiary , Protein Subunits/chemistry , Protein Subunits/metabolism , Rotation
19.
Carbohydr Polym ; 138: 49-58, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26794737

ABSTRACT

MicroRNAs (miRNAs) play important roles in the osteogenic differentiation of stem cells. However, the application of miRNA in bone regeneration has been limited by its poor stability, low cellular uptake, and undesired immune response. In this study, chitosan (CS)/tripolyphosphate (TPP)/Hyaluronic Acid (HA) nanoparticles (CTH NPs) were prepared to deliver antimiR-138 to bone marrow mesenchymal stem cells (MSCs). The particle size, polydispersity index, and zeta potential of CTH NPs were related to the weight ratio of CS:TPP:HA. At optimum N/P ratio (20:1), the highest encapsulation efficiency was obtained. Both blank CTH NPs and CTH/antmiR-138 NPs exhibited no cytotoxicity to MSCs. A high transfection efficiency (nearly 70%) and significant enhancement of the osteogenesis of MSCs were observed. Above results demonstrated that CTH NPs was a potential candidate as an efficient non-viral miRNA vector to regulate the osteogenic differentiation of MSCs.


Subject(s)
Chitosan/chemistry , Drug Carriers/chemistry , Mesenchymal Stem Cells/cytology , MicroRNAs/metabolism , Nanoparticles/chemistry , Animals , Antigens, CD/metabolism , Cell Differentiation/drug effects , Cell Survival/drug effects , Drug Carriers/toxicity , Hyaluronic Acid/chemistry , Mesenchymal Stem Cells/metabolism , Microscopy, Fluorescence , Osteogenesis/drug effects , Particle Size , Polyphosphates/chemistry , Rats , Transfection
20.
J Biomater Appl ; 30(7): 889-99, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26359295

ABSTRACT

Total auricular reconstruction is still a challenge, and autologous cartilage transplant is the main therapy so far. Tissue engineering provides a promising method for auricular cartilage reconstruction. However, although degradable framework demonstrated excellent initial cosmetic details, it is difficult to maintain the auricular contour over time and the metabolites tended to be harmful to human body. In this study, biocompatible and safe nondegradable elastic polyurethane was used to make porous scaffold in specific details by rapid prototyping technology. Platelet-rich plasma contains fibrin and abundant autologous growth factors, which was used as cell carriers for in vitro expanded cells. When crosslinking polyurethane framework, platelet-rich plasma and cells together, we successfully made polyurethane/platelet-rich plasma/cell composites, and implanted them into dorsal subcutaneous space of nude mice. The results showed that this method resulted in more even cell distribution and higher cell density, promoted chondrocyte proliferation, induced higher level expressions of aggrecan and type II collagen gene, increased content of newly developed glycosaminoglycans, and produced high-quality cartilaginous tissue. This kind of cartilage tissue engineering approach may be a potential promising alternative for external ear reconstruction.


Subject(s)
Ear Cartilage/physiology , Platelet-Rich Plasma/chemistry , Polyurethanes/chemistry , Tissue Engineering/methods , Animals , Biocompatible Materials/chemistry , Cartilage, Articular/physiology , Cell Proliferation , Chondrocytes/cytology , Collagen Type II/chemistry , Ear/physiology , Extracellular Matrix/chemistry , Fibrin/chemistry , Gene Expression Regulation , Glycosaminoglycans/chemistry , Intercellular Signaling Peptides and Proteins/chemistry , Mice , Mice, Nude , Platelet Count , Porosity , Rabbits , Surface Properties , Tissue Scaffolds
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