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1.
Sci Rep ; 10(1): 2187, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32042022

RESUMO

Maintaining the pluripotency of either embryonic stem (ES) cells or induced pluripotent stem (iPS) cells is a fundamental part of stem cell research. In this study, we reported that cordycepin promoted the expression of pluripotency markers in ES and iPS cells. ES cells treated with cordycepin demonstrated their potential for generating embryoid bodies and differentiating into all three germ layers. The expression levels of phospho-Jak2, phospho-Stat3, integrin αV, and integrin ß5 were increased after cordycepin treatment. Furthermore, the protein expression levels of IL-6 family proteins (IL-6, IL-11, LIF, oncostatin M (OSM), ciliary neurotrophic factor (CNTF)), and epidermal growth factor (EGF) were also upregulated after cordycepin treatment, but were restored after co-treatment with a Jak2 inhibitor (AG490). The gene expression levels of Yamanaka factors were upregulated in mouse embryonic fibroblasts (MEFs) after cordycepin treatment. Moreover, the generation efficiencies of iPS cells were elevated after cordycepin treatment. We found that iPS cells generated after cordycepin treatment, not only expressed pluripotency markers, but also showed the ability of differentiating into neuron stem/progenitor cells. Taken together, we demonstrated that cordycepin maintained the pluripotency of stem cells via regulation of extracellular matrix (ECM) and Jak2/Stat3 signaling pathway and improved the generation efficiency of iPSCs.

2.
Clin Chim Acta ; 503: 19-34, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923423

RESUMO

Hypertriglyceridemia is a risk factor for a series of diseases, such as cardiovascular disease (CVD), diabetes and nonalcoholic fatty liver disease (NAFLD). Angiopoietin-like proteins (ANGPTLs) family, especially ANGPTL3, ANGPTL4 and ANGPTL8, which regulate lipoprotein lipase (LPL) activity, play pivotal roles in triglyceride (TG) metabolism and related diseases/complications. There are many transcriptional and post-transcriptional factors that participate in physiological and pathological regulation of ANGPTLs to affect triglyceride metabolism. This review is intended to focus on the similarity and difference in the expression, structural features, regulation profile of the three ANGPTLs and inhibitory models for LPL. Description of the regulatory factors of ANGPTLs and the properties in regulating the lipid metabolism involved in the underlying mechanisms in pathological effects on diseases will provide potential therapeutic approaches for the treatment of dyslipidemia related diseases.

3.
Food Chem Toxicol ; 136: 110942, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31705926

RESUMO

An imbalance in mitochondrial dynamics is strongly associated with Parkinson's disease. The fusion protein optic atrophy 1 (OPA1) is up-regulated through the activation of parkin-mediated IκB kinase γ (IKKγ)/p65 signaling. This study investigated whether the neuroprotection of carnosic acid (CA) from rosemary is involved in mitochondrial dynamics and OPA1 protein induction by parkin/IKKγ/p65 signaling. The neurotoxin 6-hydroxydopamine (6-OHDA) treated with SH-SY5Y cells decreased OPA1 and mitofusin 2 fusion proteins, but increased fission 1 and dynamin related protein 1 (DRP1) fission proteins. By immunofluorescence, 6-OHDA induced the fluorescence of green spots outside the mitochondria, indicating that cytochrome c was released to the cytoplasm. Except for the effects on DRP1 protein, CA pretreatment reversed these effects of 6-OHDA. Additionally, CA treatment increased the ubiquitination of IKKγ, nuclear p65 protein, OPA1-p65 DNA binding activity, and OPA1 protein. However, transfection of parkin small interfering RNA (siRNA) attenuated these effects of CA. Furthermore, transfection of OPA1 siRNA abolished the action of CA to reverse 6-OHDA-increased cytosolic cytochrome c protein, apoptotic-related protein cleavage, and cell death. In conclusion, the mechanism by which CA counteracts the toxicity of 6-OHDA is through modulation of mitochondrial dynamics and upregulation of OPA1 via activation of the parkin/IKKγ/p65 pathway.

4.
Yi Chuan ; 41(10): 919-927, 2019 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-31624054

RESUMO

Fibrillin-2 (FBN2) is an important component of microfibers which are involved in the formation of elastic fibers in connective tissue throughout the human body. Hereditary connective tissue diseases may result from genetic mutations of FBN2 causing heterogeneity of fibrin. Genetic mutations of FBN2 are associated with a variety of hereditary connective tissue diseases including Congenital Contractural Arachnodactyl (CCA), Macular Degeneration (MD), and myopathy. Studies have shown that the FBN2 gene is recognized as the only pathogenic gene related to CCA and that CCA patients have different clinical presentations depending on the identified genetic mutations at different FBN2 sites. In this review, we summarize the roles of FBN2, its mutations and impact on the physiological and pathological processes of many hereditary connective tissue diseases. We include brief descriptions of clinical manifestations of these diseases providing a basis for further exploration of the specific molecular mechanism of FBN2 gene mutation pathogenesis which provides a theoretical basis for the therapy and medications for refractory diseases caused by FBN2 gene mutation.


Assuntos
Doenças do Tecido Conjuntivo/genética , Fibrilina-2/genética , Humanos , Mutação
5.
Nutr Res Pract ; 13(4): 286-294, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31388404

RESUMO

BACKGROUND/OBJECTIVES: Docosahexaenoic acid (DHA), an n-3 long chain polyunsaturated fatty acid (LCPUFA), is acquired by dietary intake or the in vivo conversion of α-linolenic acid. Many enzymes participating in LCPUFA synthesis are regulated by peroxisome proliferator-activated receptor alpha (PPARα). Therefore, it was hypothesized that the tissue accretion of endogenously synthesized DHA could be modified by PPARα. MATERIALS/METHODS: The tissue DHA concentrations and mRNA levels of genes participating in DHA biosynthesis were compared among PPARα homozygous (KO), heterozygous (HZ), and wild type (WT) mice (Exp I), and between WT mice treated with clofibrate (PPARα agonist) or those not treated (Exp II). In ExpII, the expression levels of the proteins associated with DHA function in the brain cortex and retina were also measured. An n3-PUFA depleted/replenished regimen was applied to mitigate the confounding effects of maternal DHA. RESULTS: PPARα ablation reduced the hepatic Acox, Fads1, and Fads2 mRNA levels, as well as the DHA concentration in the liver, but not in the brain cortex. In contrast, PPARα activation increased hepatic Acox, Fads1, Fads2 and Elovl5 mRNA levels, but reduced the DHA concentrations in the liver, retina, and phospholipid of brain cortex, and decreased mRNA and protein levels of the brain-derived neurotrophic factor in brain cortex. CONCLUSIONS: LCPUFA enzyme expression was altered by PPARα. Either PPARα deficiency or activation-decreased tissue DHA concentration is a stimulus for further studies to determine the functional significance.

6.
Toxins (Basel) ; 11(5)2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072027

RESUMO

Aflatoxins are carcinogenic secondary metabolites of fungi that contaminate many staple crops and foods. Aflatoxin contamination is a worldwide problem, especially in developing countries, posing health hazards, e.g., causing aflatoxicosis and hepatocellular carcinoma, and even death. Biological solutions for aflatoxin detoxification are environmentally friendly and a cheaper alternative than chemical methods. The aims of the current study were to investigate: (1) the ability of MSMEG_5998, an aflatoxin-degrading F420H2-dependent reductase from Mycobacterium smegmatis, to degrade aflatoxin B1 (AFB1) and reduce AFB1-caused damage in HepG2 cell culture model; and (2) whether a thioredoxin (Trx) linkage of MSMEG_5998 enhanced the enzyme activity. We show that Trx-linked MSMEG_5998 degraded 63% AFB1 and native MSMEG_5998 degraded 31% after 4 h at 22 °C, indicating that the Trx-linked enzyme had a better AFB1-degrading ability. In a HepG2 cell culture model, Trx-linked MSMEG_5998 reduced DNA damage and p53-mediated apoptosis caused by AFB1 to a greater extent than the native enzyme. These findings suggest that Trx-linked MSMEG_5998 could potentially be developed to protect the liver from AFB1 damage, or as a candidate protein to reduce AFB1-related toxicity in animals.

7.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(2): 172-175, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30782282

RESUMO

OBJECTIVE: To explore the value of galactose-deficient IgA1 (Gd-IgA1) in the early diagnosis of Henoch-Schönlein purpura nephritis (HSPN) in children. METHODS: A total of 67 hospitalized children who were definitely diagnosed with HSPN between January and April 2018 and 58 hospitalized children with Henoch-Schönlein purpura (HSP) were enrolled in the study. Twenty children undergoing routine physical examinations served as controls. The levels of serum and urine Gd-IgA1 were determined using ELISA. The receiver operating characteristic curve was used to analyze the value of serum Gd-IgA1 and urine Gd-IgA1/urine creatinine ratio in the diagnosis of HSPN. RESULTS: The level of serum Gd-IgA1 and urine Gd-IgA1/urine creatinine ratio in children with HSP or HSPN were significantly higher than those in healthy control group (P<0.01), with a significantly greater increase observed in children with HSPN (P<0.01). Serum Gd-IgA1 ≥1 485.57 U/mL and/or urine Gd-IgA1/urine creatinine ratio ≥105.74 were of favorable value in the diagnosis of HSPN. During the six-month follow-up of the 49 children with HSP, the incidence of HSPN was 47% (23/49), which included a 100% incidence in children with serum Gd-IgA1 ≥1 485.57 U/mL and a 73% incidence in children with urine Gd-IgA1/urine creatinine ratio ≥105.74. CONCLUSIONS: Serum and urine Gd-IgA1 is of favorable clinical value in the early diagnosis of HSPN.


Assuntos
Glomerulonefrite por IGA , Púrpura de Schoenlein-Henoch , Criança , Diagnóstico Precoce , Galactose , Humanos , Imunoglobulina A
8.
Org Biomol Chem ; 17(9): 2361-2369, 2019 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-30623950

RESUMO

The first [4 + 2] cyclization of para-quinone methide (p-QM) derivatives with allenes has been established via phosphine catalysis, which afforded a series of chroman derivatives in high yields (up to 97%) and excellent (E/Z)-selectivities (all >95 : 5 E/Z). This reaction will not only enrich the research contents of cyclization reactions involving p-QM derivatives, but also provide a good example of the application of allenes and phosphine catalysis in cyclization reactions. In addition, this approach also offers a useful method for the construction of chroman scaffolds.

9.
Cell Transplant ; 27(3): 456-470, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29756519

RESUMO

Parkinson's disease (PD) causes motor dysfunction and dopaminergic cell death. Drug treatments can effectively reduce symptoms but often cause unwanted side effects. Stem cell therapies using cell replacement or indirect beneficial secretomes have recently emerged as potential therapeutic strategies. Although various types of stem cells have been proposed as possible candidates, adipose-derived stem cells (ADSCs) are easily obtainable, more abundant, less ethically disputed, and able to differentiate into multiple cell lineages. However, treatment of PD using adult stem cells is known to be less efficacious than neuron or embryonic stem cell transplantation. Therefore, improved therapies are urgently needed. n-Butylidenephthalide (BP), which is extracted from Angelica sinensis, has been shown to have anti-inflammatory and neuroprotective effects. Indeed, we previously demonstrated that BP treatment of ADSCs enhances the expression of neurogenesis and homing factors such as nuclear receptor related 1 protein, stromal-derived factor 1, and brain-derived neurotrophic factor. In the present study, we examined the ability of BP-pretreated ADSC transplantation to improve PD motor symptoms and protect dopamine neurons in a mouse model of PD. We evaluated the results using neuronal behavior tests such as beam walking, rotarod, and locomotor activity tests. ADSCs with or without BP pretreatment were transplanted into the striatum. Our findings demonstrated that ADSC transplantation improved motor abilities with varied efficacies and that BP stimulation improved the therapeutic effects of transplantation. Dopaminergic cell numbers returned to normal in ADSC-transplanted mice after 22 d. In summary, stimulating ADSCs with BP improved PD recovery efficiency. Thus, our results provide important new strategies to improve stem cell therapies for neurodegenerative diseases in future studies.


Assuntos
Adipócitos/efeitos dos fármacos , Adipócitos/fisiologia , Doença de Parkinson/terapia , Anidridos Ftálicos/farmacologia , Adipócitos/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
Cell Transplant ; 27(2): 275-284, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29637814

RESUMO

It is extremely challenging to achieve strong adhesion in soft tissues while minimizing toxicity, tissue damage, and other side effects caused by wound sealing materials. In this study, flexible synthetic hydrogel sealants were prepared based on polyethylene glycol (PEG) materials. PEG is a synthetic material that is nontoxic and inert and, thus, suitable for use in medical products. We evaluated the in vitro biocompatibility tests of the dressings to assess cytotoxicity and irritation, sensitization, pyrogen toxicity, and systemic toxicity following the International Organization for Standardization 10993 standards and the in vivo effects of the hydrogel samples using Coloskin liquid bandages as control samples for potential in wound closure.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Polietilenoglicóis/química , Animais , Materiais Biocompatíveis/farmacologia , Masculino , Coelhos , Cicatrização/efeitos dos fármacos
11.
Front Neurol ; 9: 116, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29551991

RESUMO

Background and purpose: The blood-brain barrier (BBB) not only provides a physical obstruction but also recruits and activates neutrophils in cases of infection. Hemorrhagic or ischemic stroke reportedly induces the disruption of the BBB. However, few studies have reported a correlation between the incidence of meningitis in patients with a history of stroke. This study tested the hypothesis that patients with a history of stroke may be more vulnerable to meningitis. Methods: Stroke and age-matched comparison (n = 29,436 and 87,951, respectively) cohorts were recruited from the Taiwan National Health Insurance database (2000-2011). Correlations between the two cohorts were evaluated by Cox proportional hazard regression model, Kaplan-Meier curve, and log-rank tests. Results: The incidence of meningitis was higher in the stroke cohort compared to that in the comparison cohort [hazard ratio (HR), 2.89; 95% confidence interval (CI), 2.23-3.74, p < 0.001]. After adjusting for age, sex, and comorbidities, the estimated HR in the stroke cohort was 2.55-fold higher than that in the comparison cohort (CI, 1.94-3.37; p < 0.001). Notably, patients who had experienced hemorrhagic stroke had a higher incidence rate of meningitis than those with a history of ischemic stroke, except for patients older than 75 years (incidence rates in hemorrhagic/ischemic stroke patients, 3.14/1.48 in patients younger than 45 years, 1.52/0.41 in 45- to 64-year group, 1.15/0.90 in 65- to 74-year group, 0.74/0.93 in patients older than 75 years). Moreover, stroke patients who had undergone head surgery had the highest meningitis risk (adjusted HR, 8.66; 95% CI, 5.55-13.5; p < 0.001) followed by stroke patients who had not undergone head surgery (adjusted HR, 2.11; 95% CI, 1.57-2.82; p < 0.001). Conclusion: Our results indicated that stroke patients have higher risks of meningitis. Compromised BBB integrity in stroke patients may lead to increased vulnerability to infectious pathogens. In summary, our study provided new evidence of the clinical relationship between stroke and meningitis, and our findings suggest the need for precautions to prevent meningitis in stroke patients.

12.
Mol Neurobiol ; 55(2): 1786-1794, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28224479

RESUMO

The mediation of apoptosis-related protein in the TGF-ß signaling pathway (ARTS) and X-liked inhibitor of apoptosis protein (XIAP) by parkin plays a critical role in preventing Parkinson's disease. We studied whether carnosic acid (CA) could prevent 6-hydroxydopamine (6-OHDA)-induced apoptosis by modulating ARTS and XIAP through parkin in SH-SY5Y cells. In cells treated with 6-OHDA, the protein expression of ARTS is increased and XIAP is decreased. Pretreatment of cells with CA reversed these effects. Moreover, CA attenuated the activation of caspase 9 and caspase 7 by 6-OHDA. By immunoprecipitation with ARTS antibody, we found that 6-OHDA increased the protein expression of XIAP. However, pretreatment of cells with CA reduced XIAP protein and increased the ubiquitination of ARTS. Silencing of parkin attenuated the ability of CA to reverse the induction of ARTS and apoptotic-related proteins and the reduction of XIAP and parkin protein by 6-OHDA. Similarly, reversal of 6-OHDA-induced nuclear condensation and apoptotic-related proteins by CA was inhibited in cells with XIAP silencing. In conclusion, CA induces parkin by enhancing the ubiquitination of ARTS, leading to induction of XIAP. This may be a novel strategy for preventing Parkinson's disease.


Assuntos
/farmacologia , Apoptose/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oxidopamina/farmacologia , Septinas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Apoptose/fisiologia , Linhagem Celular Tumoral , Humanos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ubiquitinação
13.
Food Chem Toxicol ; 103: 194-202, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28288932

RESUMO

Pi class of glutathione S-transferase (GST) is known to suppress c-Jun N-terminal kinase (JNK)-related apoptosis through protein-protein interactions. Moreover, signaling by PKA/cAMP response element binding protein (CREB) is necessary for GSTP up-regulation. This study explored whether carnosic acid (CA) from rosemary prevents 6-hydroxydopamine (6-OHDA)-induced neurotoxicity by inhibition of JNK through GSTP via PKA/CREB signaling. Results indicated that the GSTP protein was increased in SH-SY5Y cells treated with CA for 18 and 24 h. However, CA had no significant effect on alpha or mu class of GST. Treatment of CA increased the induction of p-PKAα, nuclear p-CREB, and CRE-DNA binding activity. These effects of CA were attenuated in cells pretreated with the PKA inhibitor H89. CA pretreatment suppressed 6-OHDA-induced apoptosis by inhibition of JNK phosphorylation, poly(ADP)-ribose polymerase cleavage, and nuclear condensation. Pretreatment with H89 and GSTP siRNA attenuated the ability of CA to reverse 6-OHDA-induced apoptosis. By use of immunoprecipitation with JNK antibody to examine the interaction of GSTP-JNK with CA, we showed that CA pretreatment increased the immunoprecipitation of GSTP after 6-OHDA treatment, which suggests that CA promoted the interaction between GSTP and JNK. CONCLUSION: CA prevents 6-OHDA-induced apoptosis via inhibition of JNK by GSTP through the PKA/CREB pathway.


Assuntos
/farmacologia , Apoptose/efeitos dos fármacos , Glutationa S-Transferase pi/metabolismo , MAP Quinase Quinase 4/antagonistas & inibidores , Oxidopamina/toxicidade , Apoptose/fisiologia , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Glutationa S-Transferase pi/genética , Humanos , Isoquinolinas/farmacologia , MAP Quinase Quinase 4/metabolismo , Fármacos Neuroprotetores/farmacologia , Fosforilação/efeitos dos fármacos , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia
14.
Cell Transplant ; 26(12): 1903-1918, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29390878

RESUMO

Parkinson's disease (PD) is the second most common degenerative disorder of the central nervous system in the elderly. It is characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, as well as by motor dysfunction. Although the causes of PD are not well understood, aggregation of α-synuclein (α-syn) in neurons contributes to this disease. Current therapeutics for PD provides satisfactory symptom relief but not a cure. Treatment strategies include attempts to identify new drugs that will prevent or arrest the progressive course of PD by correcting disease-specific pathogenic process. Betulin is derived from the bark of birch trees and possesses anticancer, antimicrobial, and anti-inflammatory properties. The aim of the present study was to evaluate the potential for betulin to ameliorate PD features in Caenorhabditis elegans ( C. elegans) models. We demonstrated that betulin diminished α-syn accumulation in the transgenic C. elegans model. Betulin also reduced 6-hydroxydopamine-induced dopaminergic neuron degeneration, reduced food-sensing behavioral abnormalities, and reversed life-span decreases in a pharmacological C. elegans model. Moreover, we found that the enhancement of proteasomes activity by promoting rpn1 expression and downregulation of the apoptosis pathway gene, egl-1, may be the molecular mechanism for betulin-mediated protection against PD pathology. Together, these findings support betulin as a possible treatment for PD and encourage further investigations of betulin as an antineurodegenerative agent.


Assuntos
Fármacos Neuroprotetores/uso terapêutico , Oxidopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Degeneração Neural/tratamento farmacológico , Doença de Parkinson/patologia , Triterpenos
15.
ACS Appl Mater Interfaces ; 8(42): 28982-29000, 2016 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-27714998

RESUMO

The ideal characteristics of surface modification on the vascular graft for clinical application would be with excellent hemocompatibility, endothelialization capacity, and antirestenosis ability. Here, Fourier transform infrared spectroscopy (FTIR), surface enhanced Raman spectroscopy (SERS), atomic force microscopy (AFM), contact angle (θ) measurement, and thermogravimetric analysis (TGA) were used to evaluate the chemical and mechanical properties of collagen-gold nanocomposites (collagen+Au) with 17.4, 43.5, and 174 ppm of Au and suggested that the collagen+Au with 43.5 ppm of Au had better biomechanical properties and thermal stability than pure collagen. Besides, stromal-derived factor-1α (SDF-1α) at 50 ng/mL promoted the migration of mesenchymal stem cells (MSCs) on collagen+Au material through the α5ß3 integrin/endothelial oxide synthase (eNOS)/metalloproteinase (MMP) signaling pathway which can be abolished by the knockdown of vascular endothelial growth factor (VEGF). The potentiality of collagen+Au with MSCs for vascular regeneration was evaluated by our in vivo rat model system. Artery tissues isolated from an implanted collagen+Au-coated catheter with MSCs expressed substantial CD-31 and α-SMA, displayed higher antifibrotic ability, antithrombotic activity, as well as anti-inflammatory response than all other materials. Our results indicated that the implantation of collagen+Au-coated catheters with MSCs could be a promising strategy for vascular regeneration.


Assuntos
Células-Tronco Mesenquimais , Animais , Células Cultivadas , Colágeno , Ouro , Nanocompostos , Ratos , Fator A de Crescimento do Endotélio Vascular
16.
J Biomed Nanotechnol ; 12(4): 732-42, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27301199

RESUMO

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) are capable of self-renewal and differentiation into any cell type, thus making them the focus of many clinical application studies. Culturing ESCs on mouse embryonic fibroblast-derived and cell-based feeder layers to maintain pluripotency is a standard laboratory procedure. However, xenogeneic contamination and the large amount of time required for feeder cell preparation are two challenges that encourage the use of a murine-based feeder layer. A novel biomaterial is required to replace the current cell-based feeder system. Toward this goal, we applied a combination of biocompatible polyacrylonitrile (PAN) and electrospinning technology to establish a non-cell-based feeder layer. According to results from stem cell marker staining, scanning electron microscopy, and embryoid body formation tests, optimal ESC stemness and pluripotency were noted in three electrospun groups (2, 4, and 8 minutes), with the longer electrospinning times producing higher feeder-layer densities. KEGG pathway microarray results identified TGF-beta signaling as one of the major deregulatory pathways on electrospun-based feeder layers. Western blot data indicate significant increases in TGF-beta receptor II, phosphorylated Smad3, and Nanog protein levels in the 4- and 8-minute electrospun-based feeder layer groups compared to the non-feeder layer group. Combined, the data suggest that electrospun-based feeder layers are good candidates for maintaining ESC and iPSC pluripotency in clinical applications.


Assuntos
Resinas Acrílicas/química , Técnicas de Cultura Celular por Lotes/métodos , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Nanofibras/química , Fator de Crescimento Transformador beta/metabolismo , Animais , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Galvanoplastia/métodos , Camundongos , Camundongos Endogâmicos C57BL , Nanofibras/ultraestrutura , Tamanho da Partícula , Transdução de Sinais/fisiologia
17.
J Vet Sci ; 17(1): 71-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27051342

RESUMO

Swine influenza viruses (SwIVs) cause considerable morbidity and mortality in domestic pigs, resulting in a significant economic burden. Moreover, pigs have been considered to be a possible mixing vessel in which novel strains loom. Here, we developed and evaluated a novel M2e-multiple antigenic peptide (M2e-MAP) as a supplemental antigen for inactivated H3N2 vaccine to provide cross-protection against two main subtypes of SwIVs, H1N1 and H3N2. The novel tetra-branched MAP was constructed by fusing four copies of M2e to one copy of foreign T helper cell epitopes. A high-yield reassortant H3N2 virus was generated by plasmid based reverse genetics. The efficacy of the novel H3N2 inactivated vaccines with or without M2e-MAP supplementation was evaluated in a mouse model. M2e-MAP conjugated vaccine induced strong antibody responses in mice. Complete protection against the heterologous swine H1N1 virus was observed in mice vaccinated with M2e-MAP combined vaccine. Moreover, this novel peptide confers protection against lethal challenge of A/Puerto Rico/8/34 (H1N1). Taken together, our results suggest the combined immunization of reassortant inactivated H3N2 vaccine and the novel M2e-MAP provided cross-protection against swine and human viruses and may serve as a promising approach for influenza vaccine development.


Assuntos
Antígenos Virais/imunologia , Proteção Cruzada/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/imunologia , Peptídeos/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Peso Corporal , Modelos Animais de Doenças , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Vírus da Influenza A Subtipo H3N2/genética , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/prevenção & controle , Peptídeos/genética , Distribuição Aleatória , Análise de Sobrevida , Vacinas Sintéticas/imunologia , Replicação Viral
18.
Cell Transplant ; 25(5): 899-912, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26787228

RESUMO

Stroke is a result of cerebral ischemia that triggers a cascade of both physiological and biochemical events. No effective treatment is available for stroke; however, stem cells have the potential to rescue tissue from the effects of stroke. Adipose-derived stem cells (ADSCs) are an abundant source of adult stem cells; therefore, ADSC therapy can be considered as a future strategy for regenerative medicine. However, more research is required to improve the effectiveness of transplanted ADSCs as a treatment for stroke in the mouse stroke model. Ligustilide, isolated from the herb Angelica sinensis, exhibits a protective effect on neurons and inhibits inflammation. We also demonstrated that ligustilide treatment increases the expression levels of homing factors such as SDF-1 and CXCR4. In the present study, we evaluated the therapeutic effects of ADSC transplantation and ligustilide treatment in a mouse thromboembolic stroke model by behavioral tests, including beam walking, locomotor activity, and rotarod analysis. ADSCs pretreated with ligustilide were transplanted into the brains of stroke mice. The results showed that the therapeutic effect of ADSCs pretreated with ligustilide was better than that of ADSCs without ligustilide pretreatment. There was no difference between the recovery of mice treated by ADSC transplantation combined with subcutaneous ligustilide injection and that of mice treated only with ADSCs. The TUNEL assay showed fewer apoptotic cells in the brains of mice transplanted with ADSCs pretreated with ligustilide as well as in those without pretreatment. In summary, pretreatment of ADSCs with ligustilide improves the therapeutic efficacy of ADSC transplantation. The results of this study will help improve stem cell therapies being developed for future clinical applications.


Assuntos
4-Butirolactona/análogos & derivados , Tecido Adiposo/citologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Transplante de Células-Tronco/métodos , Células-Tronco/efeitos dos fármacos , Acidente Vascular Cerebral/terapia , Tromboembolia/terapia , 4-Butirolactona/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL12/biossíntese , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Receptores CXCR4/biossíntese , Células-Tronco/metabolismo
19.
Blood ; 127(10): 1336-45, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26679863

RESUMO

L5, the most electronegative and atherogenic subfraction of low-density lipoprotein (LDL), induces platelet activation. We hypothesized that plasma L5 levels are increased in acute ischemic stroke patients and examined whether lectin-like oxidized LDL receptor-1 (LOX-1), the receptor for L5 on endothelial cells and platelets, plays a critical role in stroke. Because amyloid ß (Aß) stimulates platelet aggregation, we studied whether L5 and Aß function synergistically to induce prothrombotic pathways leading to stroke. Levels of plasma L5, serum Aß, and platelet LOX-1 expression were significantly higher in acute ischemic stroke patients than in controls without metabolic syndrome (P < .01). In mice subjected to focal cerebral ischemia, L5 treatment resulted in larger infarction volumes than did phosphate-buffered saline treatment. Deficiency or neutralizing of LOX-1 reduced infarct volume up to threefold after focal cerebral ischemia in mice, illustrating the importance of LOX-1 in stroke injury. In human platelets, L5 but not L1 (the least electronegative LDL subfraction) induced Aß release via IκB kinase 2 (IKK2). Furthermore, L5+Aß synergistically induced glycoprotein IIb/IIIa receptor activation; phosphorylation of IKK2, IκBα, p65, and c-Jun N-terminal kinase 1; and platelet aggregation. These effects were blocked by inhibiting IKK2, LOX-1, or nuclear factor-κB (NF-κB). Injecting L5+Aß shortened tail-bleeding time by 50% (n = 12; P < .05 vs L1-injected mice), which was prevented by the IKK2 inhibitor. Our findings suggest that, through LOX-1, atherogenic L5 potentiates Aß-mediated platelet activation, platelet aggregation, and hemostasis via IKK2/NF-κB signaling. L5 elevation may be a risk factor for cerebral atherothrombosis, and downregulating LOX-1 and inhibiting IKK2 may be novel antithrombotic strategies.


Assuntos
Isquemia Encefálica/sangue , Lipoproteínas LDL/sangue , Agregação Plaquetária , Acidente Vascular Cerebral/sangue , Peptídeos beta-Amiloides/sangue , Animais , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Feminino , Humanos , Quinase I-kappa B/metabolismo , Arteriosclerose Intracraniana/sangue , Arteriosclerose Intracraniana/patologia , Trombose Intracraniana/sangue , Trombose Intracraniana/patologia , Masculino , Camundongos , Camundongos Knockout , Receptores Depuradores Classe E/metabolismo , Transdução de Sinais , Acidente Vascular Cerebral/patologia
20.
Exp Ther Med ; 10(6): 2396-2402, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26668647

RESUMO

The aim of the present study was to investigate the correlation between the efficacy of immunosuppressive therapy (IST) in children with severe aplastic anemia (SAA) and human leukocyte antigen (HLA) alleles. The polymerase chain reaction-sequence based typing high-resolution genotyping method was used to profile the HLA alleles of 115 SAA cases that were treated with rabbit-antithymocyte globulin (r-ATG) + cyclosporine (CsA) immunosuppressive therapy and 222 normal control subjects. The aim was to compare the frequency distribution of HLA alleles among the IST-effective group, the IST-ineffective group and the healthy control group. The results showed that the gene frequencies (GFs) of HLA-B*15:02, B*40:02, B*48:01, DRB1*09:01, C*01:02, C*03:04, DQB1*03:03 and DQB1*06:02 in the IST-effective group were significantly higher compared with those in the healthy control group, with a statistically significant difference. The GFs of HLA-B*15:11, B*38:01, B*39:05, DRB1*15:01, C*01:02 and C*08:22 in the IST-ineffective group were significantly increased compared with those in the healthy control group, with a statistically significant difference. The gene frequency of HLA-A*29:01 in the IST-effective group was significantly reduced compared with that in the IST-ineffective group, and the difference was statistically significant. In summary, IST efficacy in children with SAA that express the HLA-B*15:02, B*40:02, B*48:01, DRB1*09:01, C*01:02, C*03:04, DQB1*03:03 and DQB1*06:02 alleles may be superior, while the efficacy may be mitigated in children with SAA who express HLA-A*29:01, B*15:11, B*38:01, B*39:05, DRB1*15:01, C*01:02, C*08:22 alleles.

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