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1.
Clin Pathol ; 16: 2632010X231188937, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37534373

RESUMO

Background: Chronic gastritis (CG) is a very common disease. More than half of the worldwide population suffers from symptoms of CG. This disease has received great attention since the discovery of H. pylori as the most important cause of CG. Symptoms experienced by patients with CG are attributed to H. pylori-induced inflammatory reactions. Heparanase (HPSE) is a mammalian ß-endoglucoronidase. In inflammation; HPSE degrades and remodels the extracellular matrix's heparan sulfate polysaccharide chains liberating heparan sulfate-bound cytokines and chemokines, HPSE also facilitates movement of inflammatory cells. Aims: This study aimed to detect the function of HPSE in CG by correlating levels of HPSE expression with histopathological features of CG, including H. pylori infection, acute and chronic inflammatory cells, mucosal atrophic and/or metaplastic features. Methods: Ninety-five upper endoscopic-guided gastric punch biopsies were enrolled in this study. From each specimen, formalin-fixed and paraffin-embedded tissue blocks were prepared. Tissue sections were stained by Hematoxylin and eosin, Giemsa, and anti-heparanase antibody. Results: HPSE expression was statistically associated with H. pylori infection (P-value < .000), and intensity of chronic lymphocytic inflammatory infiltrate in the gastric mucosal tissues (P = .004). High levels of HPSE expression were also related to the presence of neutrophils in the gastric surface epithelium and lamina propria (P-value < .009). Conclusions: HPSE expression was upregulated in H. pylori-associated chronic gastritis. Thus, future therapeutic agents that could specifically inhibit HPSE enzyme activity, may aid in the reduction of sequelae of H. pylori infection.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123063, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37390719

RESUMO

The target of the current study is to create a novel hybrid nanocomposite (Cs@Pyc.SOF) by combining the anti-hepatitis C virus (HCV) drug sofosbuvir with the nano antioxidant pycnogenol (Pyc) and nano biomolecules like chitosan nanoparticles (Cs NPs). The characterization procedure works to verify the creation of nanocomposite (NCP) using several different techniques. UV-Vis spectroscopy is used to measure SOF loading efficiency. The various concentrations of the SOF drug were used to determine the binding constant rate Kb, which was found to be 7.35 ± 0.95 min-1 with an 83% loading efficiency. At pH 7.4, the release rate was 80.6% after two hours and 92% after 48 h, whereas at pH 6.8, it was 29% after two hours and 94% after 48 h. After 2 and 48 h, the release rate in water was 38% and 77%, respectively. . The SRB technique for fast screening is used for the cytotoxicity test, where the investigated composites show a safety status and high viability against the examined cell line. The cytotoxicity assay of the SOF hybrid materials has been identified with cell lines like mouse normal liver cells (BNL). So, Cs@Pyc.SOF was recommended as a substitute medication for the therapy of HCV, but the results need clinical studies.


Assuntos
Quitosana , Hepatite C , Animais , Camundongos , Sofosbuvir , Antivirais/uso terapêutico , Hepacivirus , Preparações Farmacêuticas , Quimioterapia Combinada , Hepatite C/tratamento farmacológico , Análise Espectral , Ribavirina
3.
PLoS One ; 16(11): e0252559, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34762669

RESUMO

Syringomyelia (SM) is a spinal cord disorder in which a cyst (syrinx) filled with fluid forms in the spinal cord post-injury/disease, in patients syrinx symptoms include loss of pain and temperature sensation or locomotion deficit. Currently, there are no small animal models and connected tools to help study the functional impacts of SM. The objective of this study was to determine the detectability of subtle locomotion deficits due to syrinx formation/expansion in post-traumatic syringomyelia (PTSM) rat model using the recently reported method of Gait Analysis Instrumentation, and Technology Optimized for Rodents (GAITOR) with Automated Gait Analysis Through Hues and Areas (AGATHA) technique. First videos of the rats were collected while walking in an arena (using GAITOR) followed by extracting meaningful locomotion information from collected videos using AGATHA protocol. PTSM injured rats demonstrated detectable locomotion deficits in terms of duty factor imbalance, paw placement accuracy, step contact width, stride length, and phase dispersion parameters compared to uninjured rats due to SM. We concluded that this technique could detect mild and subtle locomotion deficits associated with PTSM injury, which also in future work could be used further to monitor locomotion responses after different treatment strategies for SM.


Assuntos
Hiperalgesia/fisiopatologia , Locomoção/fisiologia , Medula Espinal/fisiopatologia , Siringomielia/fisiopatologia , Caminhada/fisiologia , Animais , Modelos Animais de Doenças , Análise da Marcha , Masculino , Medição da Dor , Ratos , Ratos Wistar
4.
ACS Chem Neurosci ; 12(19): 3567-3578, 2021 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550670

RESUMO

Syringomyelia (SM) is primarily characterized by the formation of a fluid-filled cyst that forms in the parenchyma of the spinal cord following injury or other pathology. Recent omics studies in animal models have identified dysregulation of solute carriers, channels, transporters, and small molecules associated with osmolyte regulation during syrinx formation/expansion in the spinal cord. However, their connections to syringomyelia etiology are poorly understood. In this study, the biological functions of the potent osmolyte betaine and its associated solute carrier betaine/γ-aminobutyric acid (GABA) transporter 1 (BGT1) were studied in SM. First, a rat post-traumatic SM model was used to demonstrate that the BGT1 was primarily expressed in astrocytes in the vicinity of syrinxes. In an in vitro system, we found that astrocytes uptake betaine through BGT1 to regulate cell size under hypertonic conditions. Treatment with BGT1 inhibitors, especially NNC 05-2090, demonstrated midhigh micromolar range potency in vitro that reversed the osmoprotective effects of betaine. Finally, the specificity of these BGT1 inhibitors in the CNS was demonstrated in vivo, suggesting feasibility for targeting betaine transport in SM. In summary, these data provide an enhanced understanding of the role of betaine and its associated solute carrier BGT1 in cell osmoregulation and implicates the active role of betaine and BGT1 in syringomyelia progression.


Assuntos
Betaína , Siringomielia , Animais , Betaína/farmacologia , Proteínas da Membrana Plasmática de Transporte de GABA , Osmorregulação , Ratos , Ácido gama-Aminobutírico/metabolismo
5.
Neural Regen Res ; 16(11): 2293-2298, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33818515

RESUMO

Precise assessment of spinal cord cystic lesions is crucial to formulate effective therapeutic strategies, yet histological assessment of the lesion remains the primary method despite numerous studies showing inconsistent results regarding estimation of lesion size via histology. On the other hand, despite numerous advances in micro-computed tomography (micro-CT) imaging and analysis that have allowed precise measurements of lesion size, there is not enough published data on its application to estimate intraspinal lesion size in laboratory animal models. This work attempts to show that micro-CT can be valuable for spinal cord injury research by demonstrating accurate estimation of syrinx size and compares between micro-CT and traditional histological analysis. We used a post-traumatic syringomyelia rat model to compare micro-CT analysis to conventional histological analysis. The study showed that micro-CT can detect lesions within the spinal cord very similar to histology. Importantly, micro-CT appears to provide more accurate estimates of the lesions with more measures (e.g., surface area), can detect compounds within the cord, and can be done with the tissue of interest (spinal cord) intact. In summary, the experimental work presented here provides one of the first investigations of the use of micro-CT for estimating the size of intraparenchymal cysts and detecting materials within the spinal cord. All animal procedures were approved by the University of Akron Institutional Animal Care and Use Committee (IACUC) (protocol # LRE 16-05-09 approved on May 14, 2016).

6.
Int J Biol Macromol ; 146: 422-430, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904458

RESUMO

Chitosan has emerged as a useful biomaterial employed in tissue engineering and drug delivery applications due to its tunable and interesting properties. However, chitosan is protonated at biological pH and thus carries positive charges, which renders chitosan incompatible with conventional methods of RNA extraction. RNA extraction is an important step in investigating cell responses and behavior through studying their gene expression transcriptional profiles. While some researchers have tried different techniques to improve the yield and purity of RNA extracted from cells encapsulated in chitosan-based biomaterials, no single study has investigated the effects of manipulating pH of the homogenate during RNA extraction on the yield and quality of total RNA. This study confirms the release and binding of RNA from chitosan to be pH dependent while analyzing the impact of pH changes during the tissue disruption and homogenization step of extraction on the resulting yield and quality of isolated RNA. This concept was applied to three commonly used methods of RNA extraction, using adult neural stem/progenitor cells (aNSPCs) encapsulated within methacrylamide chitosan (MAC) as a model chitosan-based bioscaffold. High pH conditions resulted in high yields with good quality using both TRIzol and CTAB. pH of the homogenate did not affect RNeasy spin columns, which worked best in neutral conditions with good quality, however, the overall yield was low. Results in total show that pH affected RNA interaction with a chitosan-based bioscaffold, and thus altered the concentration, purity, and integrity of isolated RNA, dependent on the method used.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , RNA/isolamento & purificação , Acrilamidas/química , Células-Tronco Adultas/metabolismo , Animais , Feminino , Regulação da Expressão Gênica , Concentração de Íons de Hidrogênio , Células-Tronco Neurais/metabolismo , Ratos Endogâmicos F344 , Eletricidade Estática
7.
Environ Monit Assess ; 191(6): 367, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31093780

RESUMO

The biological marine system in the Mediterranean Sea off Alexandria, Egypt, was investigated to recognise its biodiversity and the relations among "ichthyofauna, invertebrates, and benthic" cover including biota and flora, as well as seabed bathymetry during 2017 using a multi-seasonal surveys by the commercial bottom trawler. Moreover, zooplanktonic community from the water column was also collected to support the picture of the biodiversity in the investigated area. The identified species were 94 fishes, 64 invertebrates, 6 benthic flora, and 304 zooplanktonic species. The ichthyofauna included 5 Chondrichthyes species (5.3% of the fish species), while Osteichthyes fishes were 89 species (94.7%) belonging to 48 families and 72 genera. The most abundant family was Sparidae (13 species). The highest abundance of fishes occurred in the summer (68 fish species 72.34%), while the lowest abundance occurred in the spring (49 species, 52.13%). Regarding the demersal and benthic biota, the most abundant phylum was Mollusca (31 species) and represented by three classes (Bivalvia, Cephalopoda, and Gastropoda). Gastropoda was the most abundant class (18 species), while the lowest Phyla was Chordata (1 species of Ascidians) and Annelida (1 species). The number of lessepsian fish species were 17 (18.1%) of the total number of species caught by the bottom trawl net. In addition, this work provided new records Aulopareia unicolor (F): Gobiidae) for the area for first time and considered the second time in Egypt. The benthic flora was represented by 6 species belonging to three phyla (Tracheophyta, Chlorophyta, and Rhodophyta). Sea grasses were represented by three species (Posidonia oceanica, Cymodocea nodosa, and Halophila stipulacea). The highest abundance of benthic species occurred in the summer (53 species with 75.7%), while the lowest one was in autumn (27 species, 38.6%). Geologically, the fishing ground constituted of hard rocks to very fine silt. The eastern part of the study area includes terrigenous Nile sediment origin, while the western side has biocalcareous sediment with shell fragments richness, coastal limestone ridges origin. The continental shelf, which runs along the study area, is portrayed by a 200-m contour line. In the water column, zooplanktonic community was represented by 304 taxa, belonging to 12 phyla, 6 phyla (Arthropoda, Tintinnida, Chordata "fish eggs and larvae", Cnidaria, Foraminifera, and Radiozoa) were dominant. Copepods were the dominant group (71.59%); its annual average abundance was 1271 ind./m3. Its most diversified season was the winter (175 No/m3.) and its average abundance was 1892.9 ind./m3. However, in spring, 118 species were recorded presenting the highest average abundance (2419.4 ind./m3). The lowest diversified season was summer (85 organisms) with density of 1150 ind./m3. The present work offers updated data regarding the marine biodiversity in Egypt, enriches the gaps in the bibliography in the Eastern Mediterranean, and gives preliminary list of species and biodiversity of bottom trawl combined with the interaction with other biosystems and features of fishing ground. These data could be used to monitor evaluate the impact of bottom trawl on the fisheries habitats and changing in ecosystems. Also, it could be used as constructive step to manage or protect such area in combination with other. It is recommended to fulfil the need for more and detailed studies in all areas by different gears to cover the gaps in marine biodiversity data.


Assuntos
Organismos Aquáticos/classificação , Monitoramento Ambiental/métodos , Animais , Organismos Aquáticos/crescimento & desenvolvimento , Biodiversidade , Egito , Mar Mediterrâneo , Estações do Ano
8.
Ann Biomed Eng ; 47(3): 744-753, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30627839

RESUMO

A promising treatment strategy for spinal cord injury (SCI) is to reduce inhibition from chondroitin sulfate proteoglycans (CSPGs). For example, administering intracellular σ peptide (ISP) can improve the ability of axons to cross inhibitory CSPGs and improve function in rodent models of SCI. To translate such treatments into the clinic, we need robust and sensitive methods for studying rodent models. In this study, we applied a newly developed suite of quantitative gait analysis tools: gait analysis instrumentation and technology optimized for rodents (GAITOR), which consists of an arena and open-source software (AGATHA: automated gait analysis through hues and areas). We showed that GAITOR can be used to detect subtle functional improvements (measured by hindlimb duty factor imbalance) in rats following ISP administration in a T10 hemisection injury model. We demonstrated that SCI-specific parameters (right paw placement accuracy and phase dispersion) can be easily added to GAITOR to track recovery. We confirmed the gait observations via retrograde tracer uptake. We concluded that GAITOR is a powerful tool for measuring recovery after moderate/mild SCI, and could be used to replace expensive/inflexible commercially-available gait analysis techniques.


Assuntos
Análise da Marcha/métodos , Marcha/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Animais , Modelos Animais de Doenças , Feminino , Peptídeos/administração & dosagem , Ratos Endogâmicos F344 , Software , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/patologia
9.
Gene ; 689: 235-245, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30572096

RESUMO

Groupers are coral fish species of prime ecological and economic significance. The interactions among them and other coral reefs organisms aid the healthiness and species balance in this fundamental marine niches. Also, groupers are among the top priced fisheries species. The Egyptian habitats of the Red Sea are lacking genetic studies that assess species diversity for the final goal of conservation and fisheries management. Moreover, morphological similarities among these organisms sometimes hinder a proper species identification. Hence, more accurate groupers authentication methods are crucially required. Sixteen grouper species belonging to the genera Epinephelus, Anyperodon, Cephaolopholes, Aethaloperca, Variola, and Plectropomus, present in the Red Sea in Egypt, were investigated for species authentication through mitochondrial DNA variations, applying cytochrome oxidase subunit I (COI) and 12srRNA genes sequencing. GenBank comparisons, phylogenetic analyses and comparisons of pairwise distances were carried out. All these analyses aimed to species authentication and identifying their relations at the international scale. The results exhibited >98% identity with E. fasciatus, A. rogaa, C. oligosticta, E. areolatus, V. louti, P. areolatus, E. malabaricus, C. sexmaculata, E. summana, E. chlorostigma, E. polyphekadion, C. miniataus, A. leucogrammicus, E. tauvina, C. argus, C. hemistiktos. Pairwise distances showed a clear increase upon raising comparison level from among species to among-genera. Combined 12srRNA and COI genes sequencing resulted in an accurate tool for Egyptian Red Sea grouper species unambiguous discrimination. This can provide vital aid to the active efforts for these species conservation and fisheries management in Egypt and the world.


Assuntos
Bass/classificação , Bass/genética , Conservação dos Recursos Naturais , DNA Mitocondrial/genética , Pesqueiros , Marcadores Genéticos , Animais , Conservação dos Recursos Naturais/métodos , Código de Barras de DNA Taxonômico/métodos , Egito , Pesqueiros/organização & administração , Pesqueiros/normas , Especiação Genética , Oceano Índico , Tipagem Molecular , Filogenia
10.
Cells ; 7(10)2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30336590

RESUMO

A combinatorial approach integrating stem cells and capable of exploiting available cues is likely needed to regenerate lost neural tissues and ultimately restore neurologic functions. This study investigates the effects of the subcutaneous maturation of adult-derived neural stem cell (aNSCs) seeded into biomaterial constructs on aNSC differentiation and ultimate regional neuronal identity as a first step toward a future spinal cord injury treatment. To achieve this, we encapsulated rat aNSCs in chitosan-based hydrogels functionalized with immobilized azide-tagged interferon-γ inside a chitosan conduit. Then, we implanted these constructs in the subcutaneous tissues in the backs of rats in the cervical, thoracic, and lumbar regions for 4, 6, and 8 weeks. After harvesting the scaffolds, we analyzed cell differentiation qualitatively using immunohistochemical analysis and quantitatively using RT-qPCR. Results revealed that the hydrogels supported aNSC survival and differentiation up to 4 weeks in the subcutaneous environment as marked by the expression of several neurogenesis markers. Most interesting, the aNSCs expressed region-specific Hox genes corresponding to their region of implantation. This study lays the groundwork for further translational work to recapitulate the potentially undiscovered patterning cues in the subcutaneous tissue and provide support for the conceptual premise that our bioengineering approach can form caudalized region-specific neuroepithelium.

11.
J Biomater Appl ; 33(3): 435-446, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30111249

RESUMO

The goal of the present work was to characterize a hydrogel material for localized spinal cord delivery. To address spinal cord injuries, an injectable in situ gelling system was tested utilizing a simple, effective, and rapid cross-linking method via Michael addition. Thiolated chitosan material and maleimide-terminated polyethylene glycol material were mixed to form a hydrogel and evaluated in vitro and in vivo. Three distinct thiolated chitosan precursors were made by varying reaction conditions; a modification of chitosan with Traut's reagent (2-iminothiolane) displayed the most attractive hydrogel properties once mixed with polyethylene glycol. The final hydrogel chosen for animal testing had a swelling ratio (Q) of 57.5 ± 3.4 and elastic modulus of 378 ± 72 Pa. After confirming low cellular toxicity in vitro, the hydrogel was injected into the spinal cord of rats for 1 and 2 weeks to assess host reaction. The rats displayed no overt functional deficits due to injection following initial surgical recovery and throughout the 2-week period after for both the saline-injected sham group and hydrogel-injected group. The saline and hydrogel-injected animals both showed a similar response from ED1+ microglia and GFAP overexpression. No significant differences were found between saline-injected and hydrogel-injected groups for any of the measures studied, but there was a trend toward decreased affected area size from 1 to 2 weeks in both groups. Access to the central nervous system is limited by the blood-brain barrier for noninvasive therapies; further development of the current system for localized drug or cellular delivery has the potential to shape treatments of spinal cord injury.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Quitosana/análogos & derivados , Hidrogéis/uso terapêutico , Polietilenoglicóis/uso terapêutico , Traumatismos da Medula Espinal/terapia , Animais , Materiais Biocompatíveis/química , Células Cultivadas , Quitosana/administração & dosagem , Quitosana/química , Quitosana/uso terapêutico , Quitosana/toxicidade , Módulo de Elasticidade , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/química , Hidrogéis/toxicidade , Injeções , Masculino , Teste de Materiais , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/patologia
12.
Acta Biomater ; 53: 140-151, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28161574

RESUMO

Tethered growth factors offer exciting new possibilities for guiding stem cell behavior. However, many of the current methods present substantial drawbacks which can limit their application and confound results. In this work, we developed a new method for the site-specific covalent immobilization of azide-tagged growth factors and investigated its utility in a model system for guiding neural stem cell (NSC) behavior. An engineered interferon-γ (IFN-γ) fusion protein was tagged with an N-terminal azide group, and immobilized to two different dibenzocyclooctyne-functionalized biomimetic polysaccharides (chitosan and hyaluronan). We successfully immobilized azide-tagged IFN-γ under a wide variety of reaction conditions, both in solution and to bulk hydrogels. To understand the interplay between surface chemistry and protein immobilization, we cultured primary rat NSCs on both materials and showed pronounced biological effects. Expectedly, immobilized IFN-γ increased neuronal differentiation on both materials. Expression of other lineage markers varied depending on the material, suggesting that the interplay of surface chemistry and protein immobilization plays a large role in nuanced cell behavior. We also investigated the bioactivity of immobilized IFN-γ in a 3D environment in vivo and found that it sparked the robust formation of neural tube-like structures from encapsulated NSCs. These findings support a wide range of potential uses for this approach and provide further evidence that adult NSCs are capable of self-organization when exposed to the proper microenvironment. STATEMENT OF SIGNIFICANCE: For stem cells to be used effectively in regenerative medicine applications, they must be provided with the appropriate cues and microenvironment so that they integrate with existing tissue. This study explores a new method for guiding stem cell behavior: covalent growth factor tethering. We found that adding an N-terminal azide-tag to interferon-γ enabled stable and robust Cu-free 'click' immobilization under a variety of physiologic conditions. We showed that the tagged growth factors retained their bioactivity when immobilized and were able to guide neural stem cell lineage commitment in vitro. We also showed self-organization and neurulation from neural stem cells in vivo. This approach will provide another tool for the orchestration of the complex signaling events required to guide stem cell integration.


Assuntos
Interferon gama/administração & dosagem , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Microambiente Celular , Regeneração Tecidual Guiada/métodos , Proteínas Imobilizadas/administração & dosagem , Teste de Materiais , Regeneração Nervosa , Neurogênese , Ratos , Proteínas Recombinantes de Fusão/administração & dosagem
13.
J Neurotrauma ; 34(3): 720-733, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27736311

RESUMO

Syringomyelia is a condition of the spinal cord in which a syrinx, or fluid-filled cavity, forms from trauma, malformation, or general disorder. Previous work has shown that in noncanalicular syringomyelia irregular flow and pressure conditions enhance the volumetric growth of syrinxes. A better understanding of the underlying molecular pathways associated with syrinx formation will unveil targets for treatments and possibly prevention of syringomyelia in the future. In this study, we performed an established surgical induction of a syrinx using quisqualic acid and kaolin injections in rats to characterize the injury at the molecular level by RNA sequencing and metabolomics techniques at three and six weeks post-injury. Syrinxes averaging nearly 10 mm in length formed in the rats' spinal cords; however, smaller syrinxes were also detected in saline injected surgical shams, complicating interpretation of results. Our current results indicate a robust immune response coupled with overall decreases in neuronal signal transmission of syrinx containing animals compared with controls. Although transcriptional changes indicated gliosis and loss of neurons, no neuropathic pain was detected by von Frey allodynia testing. Unique transporters were revealed to be highly dysregulated, including significant increases in betaine/glycine transporter (BGT-1), K+/Cl- co-transporter (KCC4), and aquaporin 1 (AQP1), along with the upregulation of small molecule osmolytes taurine and betaine. The identified metabolites are of particular interest because of their involvement in osmotic homeostasis and need to be investigated further for their specific involvement in trauma-induced syrinxes.


Assuntos
Agonistas de Aminoácidos Excitatórios/toxicidade , Mediadores da Inflamação/metabolismo , Metabolômica/métodos , Traumatismos da Medula Espinal/metabolismo , Siringomielia/metabolismo , Transcriptoma/fisiologia , Animais , Imunidade Celular/efeitos dos fármacos , Imunidade Celular/fisiologia , Masculino , Ratos , Ratos Wistar , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/induzido quimicamente , Traumatismos da Medula Espinal/genética , Siringomielia/induzido quimicamente , Siringomielia/genética , Transcriptoma/efeitos dos fármacos
14.
Adv Healthc Mater ; 5(7): 802-12, 2016 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-26913590

RESUMO

Spinal cord injury (SCI) causes permanent, often complete disruption of central nervous system (CNS) function below the damaged region, leaving patients without the ability to regenerate lost tissue. To engineer new CNS tissue, a unique spinal cord bridge is created to deliver stem cells and guide their organization and development with site-specifically immobilized growth factors. In this study, this bridge is tested, consisting of adult neural stem/progenitor cells contained within a methacrylamide chitosan (MAC) hydrogel and protected by a chitosan conduit. Interferon-γ (IFN-γ) and platelet-derived growth factor-AA (PDGF-AA) are recombinantly produced and tagged with an N-terminal biotin. They are immobilized to streptavidin-functionalized MAC to induce either neuronal or oligodendrocytic lineages, respectively. These bridges are tested in a rat hemisection model of SCI between T8 and T9. After eight weeks treatments including chitosan conduits result in a significant reduction in lesion area and macrophage infiltration around the lesion site (p < 0.0001). Importantly, neither immobilized IFN-γ nor PDGF-AA increased macrophage infiltration. Retrograde tracing demonstrates improved neuronal regeneration through the use of immobilized growth factors. Immunohistochemistry staining demonstrates that immobilized growth factors are effective in differentiating encapsulated cells into their anticipated lineages within the hydrogel, while qualitatively reducing glial fibrillary acid protein expression.


Assuntos
Hidrogel de Polietilenoglicol-Dimetacrilato/química , Proteínas Imobilizadas/uso terapêutico , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/terapia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Cicatriz/patologia , Feminino , Proteínas Imobilizadas/farmacologia , Imunidade/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Atividade Motora/efeitos dos fármacos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Neuroglia/patologia , Ratos Endogâmicos F344 , Proteínas Recombinantes/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , Estilbamidinas/química
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