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1.
Sci Signal ; 17(825): eadh1178, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38412254

ABSTRACT

Pyroptosis, an inflammatory form of programmed cell death, is linked to the pathology of rheumatoid arthritis (RA). Here, we investigated the molecular mechanism underlying pyroptosis in T cells isolated from patients with RA. Compared with healthy individuals, patients with RA had more pyroptotic CD4+ T cells in blood and synovia, which correlated with clinical measures of disease activity. Moreover, the mRNA expression and protein abundance of arachidonate 5-lipoxygenase (ALOX5), which converts arachidonic acid to leukotriene A4 (LTA4), were increased in CD4+ T cells from patients with RA and, among patients with RA, were lowest in those in clinical remission. Knockdown or pharmacological inhibition of ALOX5 suppressed CD4+ T cell pyroptosis and improved symptoms in two rodent models of RA. Mechanistically, the increase in ALOX5 activity in RA CD4+ T cells enhanced the production of the LTA4 derivative LTB4, which stimulated Ca2+ influx through ORAI3 channels, leading to the activation of NLRP3 inflammasomes and pyroptosis. Our findings reveal a role for ALOX5 in RA and provide a molecular basis for further exploring the clinical utility of ALOX5 inhibition in RA and for using ALOX5 as a biomarker to distinguish active disease and remission in RA.


Subject(s)
Arthritis, Rheumatoid , T-Lymphocytes , Humans , T-Lymphocytes/metabolism , Pyroptosis , Arachidonate 5-Lipoxygenase/genetics , Arachidonate 5-Lipoxygenase/metabolism , Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/metabolism , Inflammation/metabolism , CD4-Positive T-Lymphocytes/metabolism
2.
J Burn Care Res ; 45(1): 104-111, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-37436955

ABSTRACT

Keloids are benign skin tumors characterized by excessive fibroblast proliferation and collagen deposition. The current treatment of keloids with hormone drug injection, surgical excision, radiotherapy, physical compression, laser therapy, cryotherapy often have unsatisfactory outcomes. The phytochemical compounds have shown great potential in treating keloids. Tripterine, a natural triterpene derived from the traditional Chinese medicine Thunder God Vine (Tripterygium wilfordii), was previously reported to exhibit an anti-scarring bioactivity in mouse embryonic fibroblast NIH/3T3 cells. Accordingly, our study was dedicated to explore its role in regulating the pathological phenotypes of keloid fibroblasts. Human keloid fibroblasts were treated with tripterine (0-10 µM) for 24 hours. Cell viability, proliferation, migration, apoptosis, and extracellular matrix (ECM) deposition were determined by CCK-8, EdU, wound healing, Transwell, flow cytometry, western blotting, and RT-qPCR assays. The effects of tripterine treatment on reactive oxygen species (ROS) generation and JNK activation in keloid fibroblasts were assessed by DCFH-DA staining and western blotting analysis. Tripterine at the concentrations higher than 4 µM attenuated the viability of human keloid fibroblasts in a dose-dependent manner. Treatment with tripterine (4, 6, and 8 µM) dose-dependently inhibited cell proliferation and migration, promoted cell apoptosis, reduced α-SMA, Col1, and Fn expression, induced ROS production, and enhanced JNK phosphorylation in keloid fibroblasts. Collectively, tripterine ameliorates the pathological characteristics of keloid fibroblasts that are associated with keloidformation and growth by inducing ROS generation and activating JNK signalingpathway.


Subject(s)
Burns , Keloid , Humans , Animals , Mice , Keloid/metabolism , Reactive Oxygen Species/metabolism , Reactive Oxygen Species/pharmacology , Reactive Oxygen Species/therapeutic use , Fibroblasts/metabolism , Burns/pathology , Cell Proliferation , Apoptosis , Cells, Cultured
3.
Bioact Mater ; 33: 572-590, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38111651

ABSTRACT

A central question in neural tissue engineering is how the tissue-engineered nerve (TEN) translates detailed transcriptional signals associated with peripheral nerve regeneration into meaningful biological processes. Here, we report a skin-derived precursor-induced Schwann cell (SKP-SC)-mediated chitosan/silk fibroin-fabricated tissue-engineered nerve graft (SKP-SCs-TEN) that can promote sciatic nerve regeneration and functional restoration nearly to the levels achieved by autologous nerve grafts according to behavioral, histological, and electrophysiological evidence. For achieving better effect of neuroregeneration, this is the first time to jointly apply a dynamic perfusion bioreactor and the ascorbic acid to stimulate the SKP-SCs secretion of extracellular matrix (ECM). To overcome the limitation of traditional tissue-engineered nerve grafts, jointly utilizing SKP-SCs and their ECM components were motivated by the thought of prolongating the effect of support cells and their bioactive cues that promote peripheral nerve regeneration. To further explore the regulatory model of gene expression and the related molecular mechanisms involved in tissue engineering-aided peripheral nerve regeneration, we performed a cDNA microarray analysis of gene expression profiling, a comprehensive bioinformatics analysis and a validation study on the grafted segments and dorsal root ganglia tissues. A wealth of transcriptomic and bioinformatics data has revealed complex molecular networks and orchestrated functional regulation that may be responsible for the effects of SKP-SCs-TEN on promoting peripheral nerve regeneration. Our work provides new insights into transcriptomic features and patterns of molecular regulation in nerve functional recovery aided by SKP-SCs-TEN that sheds light on the broader possibilities for novel repair strategies of peripheral nerve injury.

4.
Mater Today Bio ; 21: 100718, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37455820

ABSTRACT

Neural tissue engineering techniques typically face a significant challenge, simulating complex natural vascular systems that hinder the clinical application of tissue-engineered nerve grafts (TENGs). Here, we report a subcutaneously pre-vascularized TENG consisting of a vascular endothelial growth factor-induced host vascular network, chitosan nerve conduit, and inserted silk fibroin fibers. Contrast agent perfusion, tissue clearing, microCT scan, and blood vessel 3D reconstruction were carried out continuously to prove whether the regenerated blood vessels were functional. Moreover, histological and electrophysiological evaluations were also applied to investigate the efficacy of repairing peripheral nerve defects with pre-vascularized TENG. Rapid vascular inosculation of TENG pre-vascularized blood vessels with the host vascular system was observed at 4 â€‹d bridging the 10 â€‹mm sciatic nerve defect in rats. Transplantation of pre-vascularized TENG in vivo suppressed proliferation of vascular endothelial cells (VECs) while promoting their migration within 14 â€‹d post bridging surgery. More importantly, the early vascularization of TENG drives axonal regrowth by facilitating bidirectional migration of Schwann cells (SCs) and the bands of Büngner formation. This pre-vascularized TENG increased remyelination, promoted recovery of electrophysiological function, and prevented atrophy of the target muscles when observed 12 weeks post neural transplantation. The neural tissue-engineered pre-vascularization technique provides a potential approach to discover an individualized TENG and explore the innovative neural regenerative process.

5.
PLoS One ; 18(6): e0287760, 2023.
Article in English | MEDLINE | ID: mdl-37390061

ABSTRACT

The strategic exploration of urban sports tourism resources and the pursuit of novel trajectories for urban growth are pivotal for resource integration and competitive enhancement within cities. This investigation concentrates on Chinese city marathons and compiles daily search index data from Baidu for 38 city marathons across the nation, spanning from January 1st, 2012 to May 3rd, 2022. Employing time series clustering to evaluate the data, and in conjunction with indices related to urban tourism resources and city development, we delve into the characteristics of how Chinese city marathons propel urban growth. The findings illustrate that the search index data for the 38 city marathons can be clustered into three categories, with Xi'an, Fuzhou, and Dalian emerging as the epicenters of clustering. The representative search index data for these three clusters reveal diverse characteristics of change. The search index shifts for three landmark races align generally with the changes observed in their respective cluster center races, however, variations exist among the search index changes for these iconic marathons. The degree of search index and its trending direction in city marathons emanate from the synergistic influence of the city's political, economic, and tourism attributes, in addition to the event's prominence. City marathons also catalyze urban development through economic stimulation, image enhancement, and infrastructure improvement. Future exploration of novel trajectories for urban development could be facilitated through harnessing the economic and tourism attributes of these events, and by orchestrating a unified series of marathons.


Subject(s)
Marathon Running , Urban Renewal , Time Factors , China
6.
Glia ; 71(7): 1755-1769, 2023 07.
Article in English | MEDLINE | ID: mdl-36971489

ABSTRACT

Prevascularization strategies have become a hot spot in tissue engineering. As one of the potential candidates for seed cells, skin precursor-derived Schwann cells (SKP-SCs) were endowed with a new role to more efficiently construct prevascularized tissue-engineered peripheral nerves. The silk fibroin scaffolds seeded with SKP-SCs were prevascularized through subcutaneously implantation, which was further assembled with the SKP-SC-containing chitosan conduit. SKP-SCs expressed pro-angiogenic factors in vitro and in vivo. SKP-SCs significantly accelerated the satisfied prevascularization in vivo of silk fibroin scaffolds compared with VEGF. Moreover, the NGF expression revealed that pregenerated blood vessels adapted to the nerve regeneration microenvironment through reeducation. The short-term nerve regeneration of SKP-SCs-prevascularization was obviously superior to that of non-prevascularization. At 12 weeks postinjury, both SKP-SCs-prevascularization and VEGF-prevascularization significantly improved nerve regeneration with a comparable degree. Our figures provide a new enlightenment for the optimization of prevascularization strategies and how to further utilize tissue engineering for better repair.


Subject(s)
Fibroins , Tissue Engineering , Vascular Endothelial Growth Factor A , Peripheral Nerves , Schwann Cells/physiology , Nerve Regeneration/physiology
7.
Neuro Oncol ; 24(4): 584-597, 2022 04 01.
Article in English | MEDLINE | ID: mdl-34562087

ABSTRACT

BACKGROUND: Tumor-associated macrophages/microglia (TAMs) are prominent microenvironment components in human glioblastoma (GBM) that are potential targets for anti-tumor therapy. However, TAM depletion by CSF1R inhibition showed mixed results in clinical trials. We hypothesized that GBM subtype-specific tumor microenvironment (TME) conveys distinct sensitivities to TAM targeting. METHODS: We generated syngeneic PDGFB- and RAS-driven GBM models that resemble proneural-like and mesenchymal-like gliomas, and determined the effect of TAM targeting by CSF1R inhibitor PLX3397 on glioma growth. We also investigated the co-targeting of TAMs and angiogenesis on PLX3397-resistant RAS-driven GBM. Using single-cell transcriptomic profiling, we further explored differences in TME cellular compositions and functions in PDGFB- and RAS-driven gliomas. RESULTS: We found that growth of PDGFB-driven tumors was markedly inhibited by PLX3397. In contrast, depletion of TAMs at the early phase accelerated RAS-driven tumor growth and had no effects on other proneural and mesenchymal GBM models. In addition, PLX3397-resistant RAS-driven tumors did not respond to PI3K signaling inhibition. Single-cell transcriptomic profiling revealed that PDGFB-driven gliomas induced expansion and activation of pro-tumor microglia, whereas TAMs in mesenchymal RAS-driven GBM were enriched in pro-inflammatory and angiogenic signaling. Co-targeting of TAMs and angiogenesis decreased cell proliferation and changed the morphology of RAS-driven gliomas. CONCLUSIONS: Our work identifies functionally distinct TAM subpopulations in the growth of different glioma subtypes. Notably, we uncover a potential responsiveness of resistant mesenchymal-like gliomas to combined anti-angiogenic therapy and CSF1R inhibition. These data highlight the importance of characterization of the microenvironment landscape in order to optimally stratify patients for TAM-targeted therapy.


Subject(s)
Brain Neoplasms , Glioblastoma , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Glioblastoma/genetics , Glioblastoma/pathology , Humans , Microglia/pathology , Phosphatidylinositol 3-Kinases , Tumor Microenvironment , Tumor-Associated Macrophages
8.
Nanoscale ; 14(2): 350-360, 2022 Jan 06.
Article in English | MEDLINE | ID: mdl-34908077

ABSTRACT

Injectable shear-thinning biomaterials (STBs) have attracted significant attention because of their efficient and localized delivery of cells as well as various molecules ranging from growth factors to drugs. Recently, electrostatic interaction-based STBs, including gelatin/LAPONITE® nanocomposites, have been developed through a simple assembly process and show outstanding shear-thinning properties and injectability. However, the ability of different compositions of gelatin and LAPONITE® to modulate doxorubicin (DOX) delivery at different pH values to enhance the effectiveness of topical skin cancer treatment is still unclear. Here, we fabricated injectable STBs using gelatin and LAPONITE® to investigate the influence of LAPONITE®/gelatin ratio on mechanical characteristics, capacity for DOX release in response to different pH values, and cytotoxicity toward malignant melanoma. The release profile analysis of various compositions of DOX-loaded STBs under different pH conditions revealed that lower amounts of LAPONITE® (6NC25) led to higher pH-responsiveness capable of achieving a localized, controlled, and sustained release of DOX in an acidic tumor microenvironment. Moreover, we showed that 6NC25 had a lower storage modulus and required lower injection forces compared to those with higher LAPONITE® ratios. Furthermore, DOX delivery analysis in vitro and in vivo demonstrated that DOX-loaded 6NC25 could efficiently target subcutaneous malignant tumors via DOX-induced cell death and growth restriction.


Subject(s)
Melanoma , Nanoparticles , Biocompatible Materials , Doxorubicin/pharmacology , Drug Delivery Systems , Gelatin , Humans , Hydrogen-Ion Concentration , Melanoma/drug therapy , Tumor Microenvironment
9.
Biomaterials ; 280: 121251, 2022 01.
Article in English | MEDLINE | ID: mdl-34810037

ABSTRACT

A favorable microenvironment plays an important role in nerve regeneration. Extracellular matrix (ECM) derived from cultured cells or natural tissues can facilitate nerve regeneration in the presence of various microenvironmental cues, including biochemical, spatial, and biomechanical factors. This study, through proteomics and three-dimensional image analysis, determines that the components and spatial organization of the ECM secreted by bone marrow mesenchymal cells (BMSCs) are more similar to acellular nerves than those of the ECMs derived from Schwann cells (SCs), skin-derived precursor Schwann cells (SKP-SCs), or fibroblasts (FBs). ECM-modified nerve grafts (ECM-NGs) are engineered by co-cultivating BMSCs, SCs, FBs, SKP-SCs with well-designed nerve grafts used to bridge nerve defects. BMSC-ECM-NGs exhibit the most promising nerve repair properties based on the histology, neurophysiology, and behavioral analyses. The regeneration microenvironment formed by the ECM-NGs is also characterized by proteomics, and the advantages of BMSC-ECM-NGs are evidenced by the enhanced expression of factors related to neural regeneration and reduced immune response. Together, these findings indicate that BMSC-derived ECMs create a more superior microenvironment for nerve regeneration than that by the other ECMs and may, therefore, represent a potential alternative for the clinical repair of peripheral nerve defects.


Subject(s)
Nerve Regeneration , Schwann Cells , Bone Marrow Cells , Extracellular Matrix/metabolism , Nerve Regeneration/physiology , Peripheral Nerves , Schwann Cells/transplantation , Sciatic Nerve
10.
Mater Today Bio ; 12: 100158, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34841240

ABSTRACT

Tissue-engineered nerve grafts (TENGs) are the most promising way for repairing long-distance peripheral nerve defects. Chitosan and poly (lactic-co-glycolic acid) (PLGA) scaffolds are considered as the promising materials in the pharmaceutical and biomedical fields especially in the field of tissue engineering. To further clarify the effects of a chitosan conduit inserted with various quantity of poly (lactic-co-glycolic acid) (PLGA) scaffolds, and their degrades on the peripheral nerve regeneration, the chitosan nerve conduit inserted with different amounts of PLGA scaffolds were used to repair rat sciatic nerve defects. The peripheral nerve regeneration at the different time points was dynamically and comprehensively evaluated. Moreover, the influence of different amounts of PLGA scaffolds on the regeneration microenvironment including inflammatory response and cell state were also revealed. The modest abundance of PLGA is more instrumental to the success of nerve regeneration, which is demonstrated in terms of the structure of the regenerated nerve, reinnervation of the target muscle, nerve impulse conduction, and overall function. The PLGA scaffolds aid the migration and maturation of Schwann cells. Furthermore, the PLGA and chitosan degradation products in a correct ratio neutralize, reducing the inflammatory response and enhancing the regeneration microenvironment. The balanced microenvironment regulated by the degradants of appropriate PLGA scaffolds and chitosan conduit promotes peripheral nerve regeneration. The findings represent a further step towards programming TENGs construction, applying polyester materials in regenerative medicine, and understanding the neural regeneration microenvironment.

11.
Ann Transl Med ; 9(8): 634, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33987332

ABSTRACT

BACKGROUND: Prostaglandin E1 (PGE1) exerts various pharmacological effects such as membrane stabilization, anti-inflammatory functions, vasodilation, and platelet aggregation inhibition. We have previously demonstrated that PGE1 has a beneficial impact on patients suffering from intracerebral hemorrhage (ICH). The related mechanism underlying PGE1's beneficial effect on ICH treatment needs further exploration. METHODS: The present study elucidates the mechanism of PGE1 on ICH treatment using a neuronal apoptosis model in vitro. The mouse primary cortical neurons were pretreated with different concentrations of PGE1, followed by the treatment with hemin, the main catabolite in whole blood, to mimic the clinical ICH. RESULTS: Comparing with the vehicle-treated group, PGE1 prevented cultured cortical neurons from the accumulation of inhibited intracellular levels of reactive oxygen species (ROS), amelioration of mitochondrial membrane potential, and hemin-induced apoptosis. The reduction of ROS and apoptosis were associated with the up-regulation of Heme oxygenase-1 (HO-1) expression. Knockdown of nuclear transcription factor erythroid 2-related factor (Nrf2) by siRNA attenuated the upregulation of HO-1 as well as the protective effect of PGE1. CONCLUSIONS: Our work suggests that the Nrf2/HO-1 molecular pathway may play a crucial role in treating ICH patients with PGE1 and may represent novel molecular targets, resulting in discovering new drugs for ICH treatment.

12.
J Food Biochem ; 45(4): e13687, 2021 04.
Article in English | MEDLINE | ID: mdl-33665859

ABSTRACT

D. candidum Wall. ex Lindl. (D. candidum) is a traditional Chinese herbal medicine with multiple therapeutic properties. D. candidum was administered to mice with high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) and its mechanism of action was elucidated. D. candidum was intragastrically administered to HFD mice for 6 weeks at a dosage of 200 or 400 mg/kg. D. candidum reduced body weight gain and blood glucose levels in HFD mice in a dose-dependent manner, while significantly reducing lipid accumulation in the liver. D. candidum significantly regulated the expression of lipid metabolism- and gluconeogenesis-related genes and inhibited activation of the NLRP3 inflammasome. In summary, D. candidum significantly inhibits fat accumulation, maintains lipid metabolism and glucose homeostasis, and inhibits the inflammatory response in the liver of HFD mice. Our findings suggest that D. candidum may be an effective therapeutic strategy against NAFLD injury. PRACTICAL APPLICATIONS: The occurrence and development of fatty liver is closely related to abnormalities in lipid and glucose metabolism. An HFD-induced NAFLD mouse model was used to study the effects of D. candidum. After treatment with D. candidum, lipid and glucose metabolism in the mice was effectively regulated, which reduced liver damage and fat storage with obvious protective effects on the liver. Our results suggest that D. candidum has potential for further clinical application in the treatment of NAFLD.


Subject(s)
Dendrobium , Non-alcoholic Fatty Liver Disease , Animals , Diet, High-Fat/adverse effects , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/etiology
13.
Ann Transl Med ; 8(16): 988, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32953788

ABSTRACT

BACKGROUND: Peripheral nerves are able to regenerate spontaneously after injury. An increasing number of studies have investigated the mechanism of peripheral nerve regeneration and attempted to find potential therapeutic targets. The various bioinformatics analysis tools available, gene set enrichment analysis (GSEA) and protein-protein interaction (PPI) networks can effectively screen the crucial targets of neuroregeneration. METHODS: GSEA and PPI networks were constructed through ingenuity pathway analysis and sequential gene expression validation ex vitro to investigate the molecular processes at 1, 4, 7, and 14 days following sciatic nerve transection in rats. RESULTS: Immune response and the activation of related canonical pathways were classified as crucial biological events. Additionally, neural precursor cell expressed developmentally downregulated 4-like (NEDD4L), neuregulin 1 (NRG1), nuclear factor of activated T cells 2 (NFATC2), midline 1 (MID1), GLI family zinc finger 2 (GLI2), and ventral anterior homeobox 1 (VAX1), which were jointly involved in both immune response and axonal regeneration, were screened and their mRNA and protein expressions following nerve injury were validated. Among them, the expression of VAX1 continuously increased following nerve injury, and it was considered to be a potential therapeutic target. CONCLUSIONS: The combined use of GSEA and PPI networks serves as a valuable way to identify potential therapeutic targets for neuroregeneration.

14.
Small ; 16(40): e2001647, 2020 10.
Article in English | MEDLINE | ID: mdl-32790000

ABSTRACT

Thrombosis is a life-threatening pathological condition in which blood clots form in blood vessels, obstructing or interfering with blood flow. Thrombolytic agents (TAs) are enzymes that can catalyze the conversion of plasminogen to plasmin to dissolve blood clots. The plasmin formed by TAs breaks down fibrin clots into soluble fibrin that finally dissolves thrombi. Several TAs have been developed to treat various thromboembolic diseases, such as pulmonary embolisms, acute myocardial infarction, deep vein thrombosis, and extensive coronary emboli. However, systemic TA administration can trigger non-specific activation that can increase the incidence of bleeding. Moreover, protein-based TAs are rapidly inactivated upon injection resulting in the need for large doses. To overcome these limitations, various types of nanocarriers have been introduced that enhance the pharmacokinetic effects by protecting the TA from the biological environment and targeting the release into coagulation. The nanocarriers show increasing half-life, reducing side effects, and improving overall TA efficacy. In this work, the recent advances in various types of TAs and nanocarriers are thoroughly reviewed. Various types of nanocarriers, including lipid-based, polymer-based, and metal-based nanoparticles are described, for the targeted delivery of TAs. This work also provides insights into issues related to the future of TA development and successful clinical translation.


Subject(s)
Myocardial Infarction , Thrombosis , Blood Coagulation , Delayed-Action Preparations/therapeutic use , Fibrinolytic Agents/therapeutic use , Humans , Thrombosis/drug therapy
15.
Adv Healthc Mater ; 9(11): e2000527, 2020 06.
Article in English | MEDLINE | ID: mdl-32364331

ABSTRACT

Transdermal delivery of water-insoluble drugs via hydrogel-based microneedle (MN) arrays is crucial for improving their therapeutic efficacies. However, direct loading of water-insoluble drug into hydrophilic matrices remains challenging. Here, a biodegradable MN array patch that is fabricated from naturally derived polymer conjugates of gelatin methacryloyl and ß-cyclodextrin (GelMA-ß-CD) is reported. When curcumin, an unstable and water-insoluble anticancer drug, is loaded as a model drug, its stability and solubility are improved due to the formation of an inclusion complex. The polymer-drug complex GelMA-ß-CD/CUR can be formulated into MN arrays with sufficient mechanical strength for skin penetration and tunable drug release profile. Anticancer efficacy of released curcumin is observed in three-dimensional B16F10 melanoma models. The GelMA-ß-CD/CUR MN exhibits relatively higher therapeutic efficacy through more localized and deeper penetrated manner compared with a control nontransdermal patch. In vivo studies also verify biocompatibility and degradability of the GelMA-ß-CD MN arrays patch.


Subject(s)
Gelatin , beta-Cyclodextrins , Administration, Cutaneous , Drug Delivery Systems , Needles , Water
16.
Biotechnol J ; 15(8): e1900456, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32107862

ABSTRACT

Injectable shear-thinning biomaterials (iSTBs) have great potential for in situ tissue regeneration through minimally invasive therapeutics. Previously, an iSTB was developed by combining gelatin with synthetic silicate nanoplatelets (SNPs) for potential application to hemostasis and endovascular embolization. Hence, iSTBs are synthesized by varying compositions of gelatin and SNPs to navigate their material, mechanical, rheological, and bioactive properties. All compositions (each component percentage; 1.5-4.5%/total solid ranges; 3-9%) tested are injectable through both 5 Fr general catheter and 2.4 Fr microcatheter by manual pressure. In the results, an increase in gelatin contents causes decrease in swellability, increase in freeze-dried hydrogel scaffold porosity, increase in degradability and injection force during iSTB fabrication. Meanwhile, the amount of SNPs in composite hydrogels is mainly required to decrease degradability and increase shear thinning properties of iSTB. Finally, in vitro and in vivo biocompatibility tests show that the 1.5-4.5% range gelatin-SNP iSTBs are not toxic to the cells and animals. All results demonstrate that the iSTB can be modulated with specific properties for unmet clinical needs. Understanding of mechanical and biological consequences of the changing gelatin-SNP ratios through this study will shed light on the biomedical applications of iSTB on specific diseases.


Subject(s)
Biocompatible Materials , Gelatin , Silicates , Animals , Biocompatible Materials/chemical synthesis , Biocompatible Materials/toxicity , Cell Line , Cell Survival/drug effects , Embolization, Therapeutic , Gelatin/chemistry , Hemostasis , Hydrogels , Rheology , Silicates/chemistry
17.
Stem Cell Res Ther ; 10(1): 397, 2019 12 18.
Article in English | MEDLINE | ID: mdl-31852510

ABSTRACT

BACKGROUND: Emerging evidence suggests that neural crest-derived cells (NCCs) present important functions in peripheral nerve regeneration to correct the insufficiency of autogenous Schwann cells. Postmigratory NCCs have been successfully isolated from adult rat bone marrow in our previous work. In this study, we aim to provide neural crest-derived Schwann cell precursors (SCPs) for repair of nerve defects in adult rats, and partially reveal the mechanisms involved in neuroregeneration of cell therapy. METHODS: A clonal cell line of neural crest precursors of rat bone marrow origin (rBM-NCPs) with SCP identity was expanded in adherent monolayer culture to ensure the stable cell viability of NCPs and potentiate the repair of nerve defects after rBM-NCPs implantation based on tissue engineering nerve grafts (TENG). Here the behavioral, morphological, and electrophysiological detection was performed to evaluate the therapy efficacy. We further investigated the treatment with NCP-conditioned medium (NCP-CM) to sensory neurons after exposure to oxygen-glucose-deprivation (OGD) and partially compared the expression of trophic factor genes in rBM-NCPs with that in mesenchymal stem cells of bone marrow origin (rBM-MSCs). RESULTS: It was showed that the constructed TENG with rBM-NCPs loaded into silk fibroin fiber scaffolds/chitosan conduits repaired 10-mm long sciatic nerve defects more efficiently than conduits alone. The axonal regrowth, remyelination promoted the reinnervation of the denervated hind limb muscle and skin and thereby alleviated muscle atrophy and facilitated the rehabilitation of motor and sensory function. Moreover, it was demonstrated that treatment with NCP-CM could restore the cultured primary sensory neurons after OGD through trophic factors including epidermal growth factor (EGF), platelet-derived growth factor alpha (PDGFα), ciliary neurotrophic factor (CNTF), and vascular endothelial growth factor alpha (VEGFα). CONCLUSIONS: In summary, our findings indicated that monolayer-cultured rBM-NCPs cell-based therapy might effectively repair peripheral nerve defects partially through secreted trophic factors, which represented the secretome of rBM-NCPs differing from that of rBM-MSCs.


Subject(s)
Nerve Growth Factor/metabolism , Neural Crest/transplantation , Peripheral Nerve Injuries/therapy , Vascular Endothelial Growth Factor A/metabolism , Animals , Bone Marrow Cells/cytology , Cell Differentiation , Chitosan/chemistry , Fibroins/chemistry , Male , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/metabolism , Muscle, Skeletal/metabolism , Muscle, Skeletal/pathology , Nerve Regeneration , Neural Crest/cytology , Neural Crest/metabolism , Neurons/metabolism , Neurons/pathology , Peripheral Nerve Injuries/pathology , Rats , Rats, Wistar , Schwann Cells/cytology , Schwann Cells/metabolism , Tissue Engineering , Tissue Scaffolds/chemistry , Transplantation, Autologous
18.
Front Mol Neurosci ; 12: 287, 2019.
Article in English | MEDLINE | ID: mdl-31824262

ABSTRACT

Spinal cord injury (SCI) is a challenging clinical problem worldwide. The cellular state and molecular expression in spinal cord tissue after injury are extremely complex and closely related to functional recovery. However, the spatial and temporal changes of gene expression and regulation in various cell types after SCI are still unclear. Here, we collected the rostral and caudal regions to the lesion at 11 time points over a period of 28 days after rat hemisection SCI. Combining whole-transcriptome sequencing and bioinformatic analysis, we identified differentially expressed genes (DEGs) between spinal cord tissue from injured and sham-operated animals. Significantly altered biological processes were enriched from DEGs in astrocytes, microglia, oligodendrocytes, immune cells, and vascular systems after SCI. We then identified dynamic trends in these processes using the average expression profiles of DEGs. Gene expression and regulatory networks for selected biological processes were also constructed to illustrate the complicate difference between rostral and caudal tissues. Finally, we validated the expressions of some key genes from these networks, including α-synuclein, heme oxygenase 1, bone morphogenetic protein 2, activating transcription factor 3, and leukemia inhibitory factor. Collectively, we provided a comprehensive network of gene expression and regulation to shed light on the molecular characteristics of critical biological processes that occur after SCI, which will broaden the understanding of SCI and facilitate clinical therapeutics for SCI.

19.
Tissue Eng Part B Rev ; 25(6): 471-491, 2019 12.
Article in English | MEDLINE | ID: mdl-31452463

ABSTRACT

Spinal cord injury (SCI) is a serious problem that primarily affects younger and middle-aged adults at its onset. To date, no effective regenerative treatment has been developed. Over the last decade, researchers have made significant advances in stem cell technology, biomaterials, nanotechnology, and immune engineering, which may be applied as regenerative therapies for the spinal cord. Although the results of clinical trials using specific cell-based therapies have proven safe, their efficacy has not yet been demonstrated. The pathophysiology of SCI is multifaceted, complex and yet to be fully understood. Thus, combinatorial therapies that simultaneously leverage multiple approaches will likely be required to achieve satisfactory outcomes. Although combinations of biomaterials with pharmacologic agents or cells have been explored, few studies have combined these modalities in a systematic way. For most strategies, clinical translation will be facilitated by the use of minimally invasive therapies, which are the focus of this review. In addition, this review discusses previously explored therapies designed to promote neuroregeneration and neuroprotection after SCI, while highlighting present challenges and future directions. Impact Statement To date there are no effective treatments that can regenerate the spinal cord after injury. Although there have been significant preclinical advances in bioengineering and regenerative medicine over the last decade, these have not translated into effective clinical therapies for spinal cord injury. This review focuses on minimally invasive therapies, providing extensive background as well as updates on recent technological developments and current clinical trials. This review is a comprehensive resource for researchers working towards regenerative therapies for spinal cord injury that will help guide future innovation.


Subject(s)
Biocompatible Materials/chemistry , Cell- and Tissue-Based Therapy/methods , Regeneration , Spinal Cord Injuries/therapy , Stem Cells/cytology , Animals , Bioengineering , Humans
20.
Rev Assoc Med Bras (1992) ; 64(5): 454-461, 2018 May.
Article in English | MEDLINE | ID: mdl-30304146

ABSTRACT

OBJECTIVES: To evaluate the epidemiological characteristics of acute pancreatitis (AP) and explore potential relationships between these factors and severity. METHODOLOGY: Data-sets of 5,659 patients with AP from health statistics and the Information Center of Jiangsu province, between 2014 and 2016, were analyzed. A self-organizing map (SOM) neural network was used for data clustering. RESULTS: Biliary acute pancreatitis (BAP) (86.7%) was the most frequent etiological factor. A total of 804 (14.2%) patients had severe acute pancreatitis (SAP). The mean age of patients was 53.7 + 17.3 (range 12~94y). Most of the AP patients were married (75.4%); 6% of mild /moderately severe AP (MAP/MASP) patients were unmarried, which was less than SAP patients (P=0.016). AP patients with blood type AB in the general population (8.8%) was significantly lower than that of AP cases (13.9%) (P=0.019) and SAP cases(18.7%) (P=0.007). The number of AP patients in southern Jiangsu was much higher than that in northern Jiangsu province, especially in Nanjing (1229, 21.7%). The proportion of acute alcoholic pancreatitis (AAP) in the north of Jiangsu (Xuzhou 18.4%) was much higher than that in southern Jiangsu (Suzhou 2.6%). The whole sample was divided into five classes by SOM neural network. If BAP patients were male, old, divorced, and blood type AB or B, they were more likely to develop SAP. Middle-age, unmarried or divorced male patients with blood type B/AB who suffered from HAP or AAP were also more likely to develop SAP. CONCLUSIONS: The number of unmarried patients with MAP/MASP was smaller than that of SAP. Blood types AB and B were more frequent in AP, especially in SAP. The differences between southern Jiangsu and northern Jiangsu, in number of AP patients and the proportion of AAP, were significant. In class I and class IV, the ratio of SAP was much higher than in other classes and the whole sample.


Subject(s)
ABO Blood-Group System , Data Mining/methods , Pancreatitis/epidemiology , Acute Disease , Adult , Aged , China/epidemiology , Datasets as Topic , Female , Health Information Systems , Humans , Incidence , Male , Middle Aged , Neural Networks, Computer , Pancreatitis/blood , Pancreatitis/diagnosis , Severity of Illness Index
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