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1.
ACS Appl Mater Interfaces ; 15(35): 41569-41579, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37608739

RESUMEN

In recent years, various porphyrin dyes have been designed to develop efficient dye-sensitized solar cells (DSSCs). Based on our previously reported porphyrin dye XW43, which contains a phenothiazine donor with two diethylene glycol (DEG)-derived substituents, we herein report a porphyrin dye XW89 by introducing a benzo 12-crown-4 (BCE) unit onto the N atom of the phenothiazine donor. On this basis, XW90 and XW91 have been synthesized by replacing a DEG chain in XW89 with two DEG chains and a 12-crown-4 unit, respectively. For iodine electrolyte-based DSSCs, dyes XW89-XW91 exhibit VOC values of 765-779 mV, higher than that of XW43 (755 mV), which may be related to the strong capability of the BCE group in binding Li+ and thus suppressing the downward shift of the TiO2 conduction band and interfacial charge recombination. Moreover, the smaller size of 12-crown-4 than the DEG unit enables higher adsorption amounts of the dyes than XW43, contributing to an enhanced JSC value. Due to the presence of two BCE units, dye XW91 exhibits the highest dye loading amount and JSC of 1.86 × 10-7 mol cm-2 and 19.79 mA cm-2, respectively, affording a high PCE of 11.1%. To further enhance the light-harvesting ability, a concerted companion (CC) dye XW92 has been constructed by linking the two subdye units corresponding to the porphyrin dye XW91 and an organic dye. As a result, XW92 affords an enhanced JSC and efficiency. Further coadsorption of XW92 with chenodeoxycholic acid achieved the highest efficiency of 12.1%. This work provides an effective approach for fabricating efficient DSSCs sensitized by porphyrin and CC dyes based on the introduction of crown ether units with smaller sizes and stronger Li+ affinities.

2.
Molecules ; 27(6)2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35335184

RESUMEN

Mulberry leaf is an excellent protein resource that can be used as feed additive for livestock and poultry. Nevertheless, the use of mulberry leaves in animal diets is limited by its protease inhibitors, tannic acid and other anti-nutritional factors. This study systematically analyzed the type and activity of serine protease inhibitors (SPIs) from the leaves of 34 mulberry varieties, aiming to reveal the physicochemical properties and inactivation mechanism of SPIs. The types and activities of trypsin inhibitors (TIs) and chymotrypsin inhibitors (CIs) exhibited polymorphisms among different mulberry varieties. The highest number of types of inhibitors was detected in Jinshi, with six TIs (TI-1~TI-6) and six CIs (CI-1~CI-6). TIs and CIs exhibited strong thermal and acid-base stability. High-temperature and high-pressure treatment could reduce the activities of TIs and CIs to a certain extent. ß-mercaptoethanol treatment could completely abolish TIs and CIs, suggesting that the disulfide bridges were critical for their inhibitory activities. The Maillard reaction could effectively eliminate the inhibitory activities of TI-1~TI-4 and CI-1~CI-4. This study reveals the physicochemical properties and inactivation mechanisms of the anti-nutritional SPIs from mulberry leaves, which is helpful to exploit mulberry-leaf food with low-activity SPIs, promote the development and utilization of mulberry-leaf resources in animal feed and provide reference for mulberry breeding with different functions.


Asunto(s)
Morus , Animales , Frutas/química , Morus/química , Fitomejoramiento , Hojas de la Planta/química , Inhibidores de Serina Proteinasa/metabolismo , Inhibidores de Serina Proteinasa/farmacología
3.
Molecules ; 26(8)2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33924385

RESUMEN

The role of Kupffer cells (KCs) in liver regeneration is complicated and controversial. To investigate the distinct role of F4/80+ KCs at the different stages of the regeneration process, two-thirds partial hepatectomy (PHx) was performed in mice to induce physiological liver regeneration. In pre- or post-PHx, the clearance of KCs by intraperitoneal injection of the anti-F4/80 antibody (α-F4/80) was performed to study the distinct role of F4/80+ KCs during the regenerative process. In RNA sequencing of isolated F4/80+ KCs, the initiation phase was compared with the progression phase. Immunohistochemistry and immunofluorescence staining of Ki67, HNF-4α, CD-31, and F4/80 and Western blot of the TGF-ß2 pathway were performed. Depletion of F4/80+ KCs in pre-PHx delayed the peak of hepatocyte proliferation from 48 h to 120 h, whereas depletion in post-PHx unexpectedly led to persistent inhibition of hepatocyte proliferation, indicating the distinct role of F4/80+ KCs in the initiation and progression phases of liver regeneration. F4/80+ KC depletion in post-PHx could significantly increase TGF-ß2 serum levels, while TGF-ßRI partially rescued the impaired proliferation of hepatocytes. Additionally, F4/80+ KC depletion in post-PHx significantly lowered the expression of oncostatin M (OSM), a key downstream mediator of interleukin-6, which is required for hepatocyte proliferation during liver regeneration. In vivo, recombinant OSM (r-OSM) treatment alleviated the inhibitory effect of α-F4/80 on the regenerative progression. Collectively, F4/80+ KCs release OSM to inhibit TGF-ß2 activation, sustaining hepatocyte proliferation by releasing a proliferative brake.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Macrófagos del Hígado/metabolismo , Regeneración Hepática/fisiología , Hígado/metabolismo , Hígado/cirugía , Oncostatina M/metabolismo , Factor de Crecimiento Transformador beta2/metabolismo , Animales , Antígenos de Diferenciación/inmunología , Western Blotting , Células Cultivadas , Hepatectomía , Hepatocitos/metabolismo , Inmunohistoquímica , Hígado/citología , Regeneración Hepática/genética , Masculino , Ratones , Microscopía Fluorescente , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ARN , Factor de Crecimiento Transformador beta2/genética
4.
J Cancer Res Ther ; 17(7): 1608-1617, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35381729

RESUMEN

Metformin is well known as a hypoglycemic drug, which maintains glucose blood balance by attenuating hepatic glycogen synthesis and enhancing muscle glucose decomposition. The accumulation of epidemiologic studies demonstrates that metformin plays a beneficial role in preventing or treating colorectal carcinoma (CRC). Metformin intake alone or along with traditional chemotherapeutic drugs has been proved to attenuate the growth of colon cancer cells. The preventive or therapeutic efficiencies of metformin on CRC mainly include the following aspects: activating adenosine monophosphate-activated protein kinase/mammalian target of rapamycin pathway, inhibiting tumor angiogenesis, regulating immune response, enhancing cancer cells' sensitivity to chemotherapeutic agents, or inhibiting tumor stem cells. Therefore, metformin is suggested to become potential anticarcinoma agents. Nevertheless, the role of metformin in preventing and treating CRC is still controversial. In this review, we focused on the clinical value of metformin as a potentially effective anticarcinoma drug or an adjuvant agent, especially its mechanisms in CRC therapy.


Asunto(s)
Antineoplásicos , Neoplasias del Colon , Neoplasias Colorrectales , Metformina , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Colorrectales/patología , Humanos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Metformina/farmacología , Metformina/uso terapéutico
5.
Onco Targets Ther ; 12: 2323-2333, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30992669

RESUMEN

AIM: The aim of this study was to detect the effects and potential mechanisms of microRNA-221 on a series of biological behaviors of papillary thyroid carcinoma (PTC) cells in vitro and in vivo. METHODS: First, we analyzed the relationship between the expression of miR-221 and several clinicopathological features of PTC patients and then detected the expression of the miR-221 in tumor tissues and cell lines. The effects of miR-221 on proliferation and invasion of PTC cells were verified by cell counting kit-8 (CCK-8) assay, wound healing assay and transwell assay. Western blot assay was applied to explore the correlation between miR-221 and RECK expression in PTC K1 cells. Finally, a xenograft model was established to further confirm the tumor-promoting effects of miR-221 in vivo. RESULTS: Our data indicated that miR-221 was relatively upregulated in metastatic PTC tissues. MiR-221 promoted the proliferation, migration and invasion activities of PTC K1 cells, following variations of epithelial-mesenchymal transition (EMT)-related protein expression. We identified RECK as a direct target of miR-221, revealed its expression to be inversely correlated with miR-221 in PTC samples and showed that its reintroduction reverses miR-221-induced PTC invasiveness. In addition, miR-221 was also verified to promote tumor growth and increase tumor volume and weight in vivo. Taken together, miR-221/RECK axis could be an effective way to regulate biological behaviors of PTC. CONCLUSION: MiR-221 may be involved in PTC cell invasion and metastasis by targeting RECK, indicating that the miR-221/RECK pathway could be studied further as a potential new diagnostic or prognostic biomarker for PTC.

6.
Cancer Lett ; 442: 40-52, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30401637

RESUMEN

Aberrant activation of the RAS cascade ubiquitously occurs in human hepatocellular carcinomas (HCC), regardless of rare mutations of RAS. However, the association between the Ras cascade and hepatic steatosis during hepatocarcinogenesis remains under-investigated. Here, the variation in the constitutive activity of Ras signaling and HCC incidence was found in a nonalcoholic fatty liver disease (NAFLD)-HCC mouse model, and Ras activity was induced by hepatic steatosis. Even in hepatocyte-specific expression of KrasG12D (Alb-Cre/KrasG12D, Krashep) mice, mutagenic activation of Ras signaling was still significantly enhanced by NAFLD, with downregulation of negative regulators. Interestingly, hepatic steatosis could be alleviated by persistent activation of Ras, whereas Ras accelerated DNA damage and HCC progression through Carnitine palmitoyltransferase 1A (CPT1α). A close correlation between active Ras and CPT1α was also shown in clinical steatosis peri-tumor tissues of HCC samples and experimental models. CPT1α inhibitor etomoxir (ETO) largely ameliorated active Ras-drived HCC. These findings can provide a novel link between steatosis and Ras activity in liver cancer.


Asunto(s)
Carcinoma Hepatocelular/enzimología , Carnitina O-Palmitoiltransferasa/metabolismo , Transformación Celular Neoplásica/metabolismo , Dieta Alta en Grasa , Hígado Graso/metabolismo , Neoplasias Hepáticas Experimentales/enzimología , Hígado/enzimología , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/prevención & control , Carnitina O-Palmitoiltransferasa/antagonistas & inhibidores , Carnitina O-Palmitoiltransferasa/genética , Transformación Celular Neoplásica/inducido químicamente , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/patología , Daño del ADN , Dietilnitrosamina , Progresión de la Enfermedad , Inhibidores Enzimáticos/farmacología , Compuestos Epoxi/farmacología , Hígado Graso/etiología , Hígado Graso/genética , Hígado Graso/patología , Regulación Neoplásica de la Expresión Génica , Humanos , Metabolismo de los Lípidos , Hígado/efectos de los fármacos , Hígado/patología , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/prevención & control , Ratones Transgénicos , Estrés Oxidativo , Proteínas Proto-Oncogénicas p21(ras)/genética , Transducción de Señal , Factores de Tiempo
7.
BMC Ophthalmol ; 17(1): 208, 2017 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-29166888

RESUMEN

BACKGROUND: The pathogenesis of age-related macular degeneration (AMD) is complex. It has been shown that vitreomacular traction (VMT) plays a role in the pathogenesis of AMD. We speculate that the continuous stretch induced by VMT might impair the function of retinal pigment epithelium (RPE) cells and it might also be involved in the progression of AMD. METHODS: Cultured ARPE-19 cells were subjected to cyclic stretch on the Flexcell Strain system at a level of 25% increment on the surface area for 8 h, 14 h, 20 h, 24 h. In another group, the stretch was withdrawn at 14 h and the cell cultured for another 6 h. Then, we observed the changes in morphology, apoptosis and expression of interleukin 6 (IL6) and vascular endothelial growth factor (VEGF) in RPE cells under stretch. RESULTS: We found that stretch induced the RPE cells to change from a spreading shape into a rounded shape, and that the morphological changes were positively correlated with the duration of the stretch. The expression of pFAK397 and pRac1/cdc42 were elevated in a time-dependent fashion. The stretch resulted in an increase in the apoptosis ratio, with Bcl2, Bax and p53 also showing time-dependent changes. In addition, up-regulation of IL6 and VEGF expression levels was also observed. After withdrawal of the stretch, all of these changes were significantly diminished. CONCLUSION: Stretch may induce morphological, cell apoptosis, and up-regulation of cytokines changes in RPE cells, indicating that cyclic stretching may participate in the progression of AMD by impeding the functions of the RPE.


Asunto(s)
Apoptosis/fisiología , Células Epiteliales/fisiología , Interleucina-6/metabolismo , Epitelio Pigmentado de la Retina/citología , Estrés Mecánico , Factor A de Crecimiento Endotelial Vascular/metabolismo , Actinas/metabolismo , Fenómenos Biomecánicos , Western Blotting , Células Cultivadas , Células Epiteliales/metabolismo , Humanos
8.
J Vis Exp ; (128)2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-29155782

RESUMEN

Previous studies have shown that the secondary degeneration of retinal ganglion cells (RGCs) occurs commonly in glaucoma. Partial optic nerve transection is considered a useful and reproducible model. Compared with other optic nerve injury models used commonly for assessing secondary degeneration, e.g. complete optic nerve transection and optic nerve crush models, the partial optic nerve transection model is superior as it distinguishes primary from secondary degeneration in situ. Therefore, it serves as an excellent tool for evaluating secondary degeneration. This study describes a novel operative approach of partial optic nerve transection by directly accessing the area of the retrobulbar optic nerve through the orbital lateral wall of the eyeball. Moreover, we present a newly designed, low cost surgical instrument to assist with transection. As demonstrated by the representative results in distinguishing the boundary of primary and secondary injury areas, the new approach and instrument ensures high efficiency and stability of the model by providing adequate space for surgical operation. This in turn makes it easy to separate the meningeal sheath and ophthalmic vessels from the optic nerve before transection. An additional benefit is that this space-saving operative approach improves the investigators' ability to administer drugs, carriers, or selective RGC tracers to the stump of the partially transected optic nerve, allowing the exploration of mechanisms behind secondary injury in RGCs, in a new way.


Asunto(s)
Modelos Animales de Enfermedad , Traumatismos del Nervio Óptico/etiología , Nervio Óptico/cirugía , Células Ganglionares de la Retina/patología , Animales , Ratas
9.
Curr Eye Res ; 42(1): 21-27, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27259381

RESUMEN

PURPOSE: To investigate the mechanism of chitosan promoting corneal wound healing though evaluating its effect on extracellular signal-regulated kinases (ERK) and p38 pathway activity in a rabbit animal model. METHODS: Cell proliferation and migration assay were performed 24 hours after chitosan treatment. The activity of ERK and p38 pathways was detected by using immunofluorescence and Western blotting in the presence of chitosan and an ERK inhibitor. In vivo study of epithelial debridement wounds was performed on 8 mm rabbit corneas in the presence of chitosan and an ERK pathway inhibitor. RESULTS: Immunostaining with Ki67 and migrating assay showed that chitosan could upregulate the cell proliferation and promote the cell migration. Chitosan activated the ERK pathway in 5 min to 30 min after treatment but did not affect the p38 pathway. ERK inhibitor PD98059 can inhibit the chitosan-stimulated ERK phosphorylation. Chitosan increased the corneal epithelial wound closure in organ culture and ERK inhibition with PD98059 blocked the effect of chitosan on wound healing. CONCLUSIONS: Chitosan promoted corneal epithelial proliferation and migration during the wound healing in rabbits' eye. Chitosan-stimulated epithelial wound healing is partially mediated through the activation of the ERK pathway but not the p38 pathway.


Asunto(s)
Quitosano/farmacología , Lesiones de la Cornea/fisiopatología , Epitelio Corneal/fisiología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Animales , Western Blotting , Ensayos de Migración Celular , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Lesiones de la Cornea/metabolismo , Modelos Animales de Enfermedad , Flavonoides/farmacología , Técnica del Anticuerpo Fluorescente Indirecta , Antígeno Ki-67/metabolismo , Técnicas de Cultivo de Órganos , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Conejos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
10.
Mol Med Rep ; 13(4): 3121-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26934949

RESUMEN

Senescence of retinal pigment epithelium (RPE) cells is a major contributor to age­related macular degeneration (AMD). However, the molecular mechanisms underlying RPE dysfunction are not well understood. Apoptosis related protein 3 (Apr3) was originally cloned from HL­60 cells induced by all­trans retinoic acid (ATRA). Preliminary data revealed elevated Apr3 expression in the tissues of aged mice, suggesting that it is involved in the aging process. The present study demonstrated that Apr3 mRNA and protein levels were markedly increased in aged mouse RPE cells. Elevated Apr3 expression was also observed during premature senescence induced by oxidative stress (H2O2 and tert­BHP) in ARPE­19 cells. Moreover, Apr3 overexpression promoted cellular senescence in ARPE­19 cells, as characterized by enhanced senescence­associated ß­galactosidase activity, reduced cell proliferation and increased expression of the senescence markers p53 and p21. In addition, it was demonstrated that overexpression of Apr3­N, a truncated counterpart of Apr3, abrogated Apr3­induced phenotypes. It was concluded that Apr3 expression was induced in replicative and premature senescence of RPE cells and its overexpression accelerated senescence of ARPE­19 cells, which provides important insights into the function of Apr3 in senescence­associated diseases.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Senescencia Celular , Animales , Proteínas Reguladoras de la Apoptosis/genética , Western Blotting , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Humanos , Peróxido de Hidrógeno/toxicidad , Proteínas de Transporte de Membrana , Ratones , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba/efectos de los fármacos
11.
Acta Ophthalmol ; 94(3): 266-75, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26178710

RESUMEN

PURPOSE: To examine the influence of experimentally reduced cerebrospinal fluid pressure (CSFP) as compared to elevated intraocular pressure (IOP) on axonal morphology and axonal motor proteins in retinal ganglion cells (RGCs). METHODS: The experimental study included 39 rats which underwent cerebrospinal fluid drainage for 6 hr, 30 rats which unilaterally underwent IOP elevation for 6 hr and 30 rats in a control group. Six hours after baseline, the animals were killed and the eyes were histologically and immunohistochemically examined. RESULTS: In experimental models in the high-IOP group and the low-CSFP group as compared to the control group, RGC axons became abnormally dilated and accumulated vesicles. Both groups as compared to the control group showed an accumulation of dynein IC (intermediate chain) at the optic nerve head and retina and a reduction in kinesin HC (heavy chain) immunoreactivity in the optic nerve fibre axons. As a corollary, Western blot analysis revealed an elevation of dynein IC protein levels in the optic nerve head and retina and a decrease in kinesin HC protein levels in the optic nerve. CONCLUSIONS: Experimental models with an acute IOP rise or with an acute CSFP reduction showed similar morphologic changes in the retinal ganglion cell axons and similar immunohistochemical changes in the axonal motor proteins kinesin HC and dynein IC. It supports the hypothesis that an experimental model with an acute reduction in CSFP as well as an experimental model with an acute rise in IOP may share similarities in the process of optic nerve damage.


Asunto(s)
Axones/patología , Presión del Líquido Cefalorraquídeo/fisiología , Dineínas/metabolismo , Presión Intraocular/fisiología , Cinesinas/metabolismo , Nervio Óptico/patología , Células Ganglionares de la Retina/patología , Animales , Transporte Axonal/fisiología , Axones/metabolismo , Western Blotting , Modelos Animales de Enfermedad , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Imagen por Resonancia Magnética , Masculino , Nervio Óptico/metabolismo , Ratas , Ratas Sprague-Dawley , Células Ganglionares de la Retina/metabolismo
13.
Oncol Lett ; 10(1): 277-282, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26171014

RESUMEN

The activation of mammalian target of rapamycin (mTOR) has been reported in tumor development, but the role of mTOR in colorectal carcinomas remains unclear. The aim of the present study was to investigate the significance of mTOR and its downstream effector 70 kDa ribosomal protein S6 kinase (P70S6K) in human colorectal carcinomas. The phosphorylated (p-)mTOR and p-P70S6K proteins were examined by immunohistochemistry performed on tissue microarray containing tissue samples obtained from colorectal carcinoma (n=111), adenomatous polyps (n=40) and normal colonic mucosa (n=40), with a comparison between the expression of these proteins and the clinicopathological parameters of patients with carcinomas. The positive expression rates of p-mTOR and p-P70S6k were 60.4 and 65.8%, respectively, in colorectal carcinoma tissue, which was significantly increased compared with the tissue from adenomatous polyps (27.5 and 20%, respectively) and normal colonic mucosa (10.0 and 5.0%, respectively) (P<0.05). Overexpression of the p-mTOR and p-P70S6K proteins was significantly associated with the tumor-node-metastasis stage, the occurrence of distal and lymph node metastasis and the degree of differentiation. Aberrant expression of p-mTOR and p-P70S6K may contribute to the pathogenesis, growth, invasion and metastasis of colorectal carcinoma. The phosphorylation of these proteins was considered to be a promising marker to indicate the aggressive behaviors and prognosis of colorectal carcinomas. The overexpression of the mTOR/P70S6K signaling pathway may play an important role in colorectal carcinoma carcinogenesis. The expression of p-mTOR and p-P70S6K was considered as a promising marker to indicate the aggressive behaviors and prognosis of human colorectal carcinomas.

14.
Invest Ophthalmol Vis Sci ; 56(8): 4257-66, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26161987

RESUMEN

PURPOSE: To examine the influence of short-term reduction in cerebrospinal fluid pressure (CSFP) as compared with short-term elevation in IOP on axonal transport. METHODS: The study included 111 adult Sprague-Dawley rats. For 6 hours, IOP was unilaterally elevated to 40 mm Hg (IOP40-group; n = 27), IOP was unilaterally increased to a value of 25 mm Hg below the mean blood pressure (PP25-group; n = 27), or CSFP was reduced by continuous aspiration of cerebrospinal fluid (Low-CSFP-group; n = 27). A sham control group (with a trocar in cisterna magna without cerebrospinal fluid release) included 24 rats. The left eyes of the IOP40 study group and PP25 study group served as additional contralateral control group. Orthograde axonal transport was examined by intravitreally injected rhodamine-ß-isothiocyanate; retrograde axoplasmic flow was assessed by fluorogold injected into the superior colliculi. RESULTS: At 24 hours after baseline, rhodamine-ß-isothiocyanate (RITC) staining intensity of the optic nerve was lower (P < 0.05) in the IOP40-group, PP25-group, and Low-CSFP-group than in the control groups. At 6 hours after the fluorogold injection, fluorogold fluorescence was significantly lower in the IOP40-group, the PP25-group, and the Low-CSFP-group than in the control groups. At 5 days after baseline, the fluorogold fluorescence no longer differed significantly between the IOP40-group or the Low-CSFP-group and the control groups. At 1 week after baseline, retinal ganglion cell density was markedly reduced only in the PP25-group. CONCLUSIONS: Both short-term lowering of CSFP and short-term rise in IOP were associated with a disturbance of both the orthograde and retrograde axonal transport. The findings support the notion of an association between abnormally low CSFP and optic nerve damage.


Asunto(s)
Transporte Axonal/fisiología , Presión del Líquido Cefalorraquídeo/fisiología , Presión Intraocular/fisiología , Nervio Óptico/metabolismo , Animales , Modelos Animales de Enfermedad , Colorantes Fluorescentes/farmacocinética , Glaucoma/metabolismo , Glaucoma/fisiopatología , Masculino , Nervio Óptico/citología , Ratas , Ratas Sprague-Dawley , Rodaminas/farmacocinética
15.
Int J Ophthalmol ; 8(3): 622-30, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26086019

RESUMEN

Retinal degenerative diseases pose a serious threat to eye health, but there is currently no effective treatment available. Recent years have witnessed rapid development of several cutting-edge technologies, such as gene therapy, stem cell therapy, and tissue engineering. Due to the special features of ocular structure, some of these technologies have been translated into ophthalmological clinic practice with fruitful achievements, setting a good example for other fields. This paper reviews the development of the gene and stem cell therapies in ophthalmology.

16.
PLoS One ; 10(3): e0121185, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25803615

RESUMEN

The inhibition of NF-κB by genetic deletion or pharmacological inhibition of IKK2 significantly reduces laser-induced choroid neovascularization (CNV). To achieve a sustained and controlled intraocular release of a selective and potent IKK2 inhibitor, 2-[(aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA-1) (MW: 279.29), we developed a biodegradable poly-lactide-co-glycolide (PLGA) polymer-delivery system to further investigate the anti-neovascularization effects of IKK2 inhibition and in vivo biosafety using laser-induced CNV mouse model. The solvent-evaporation method produced spherical TPCA-1-loaded PLGA microparticles characterized with a mean diameter of 2.4 »m and loading efficiency of 80%. Retrobulbar administration of the TPCA-1-loaded PLGA microparticles maintained a sustained drug level in the retina during the study period. No detectable TPCA-1 level was observed in the untreated contralateral eye. The anti-CNV effect of retrobulbarly administrated TPCA-1-loaded PLGA microparticles was assessed by retinal fluorescein leakage and isolectin staining methods, showing significantly reduced CNV development on day 7 after laser injury. Macrophage infiltration into the laser lesion was attenuated as assayed by choroid/RPE flat-mount staining with anti-F4/80 antibody. Consistently, laser induced expressions of Vegfa and Ccl2 were inhibited by the TPCA-1-loaded PLGA treatment. This TPCA-1 delivery system did not cause any noticeable cellular or functional toxicity to the treated eyes as evaluated by histology and optokinetic reflex (OKR) tests; and no systemic toxicity was observed. We conclude that retrobulbar injection of the small-molecule IKK2 inhibitor TPCA-1, delivered by biodegradable PLGA microparticles, can achieve a sustained and controllable drug release into choroid/retina and attenuate laser-induced CNV development without causing apparent systemic toxicity. Our results suggest a potential clinical application of TPCA-1 delivered by microparticles in treatment of CNV in the patients with age-related macular degeneration and other retinal neovascularization diseases.


Asunto(s)
Amidas/administración & dosificación , Neovascularización Coroidal/tratamiento farmacológico , Quinasa I-kappa B/antagonistas & inhibidores , Ácido Láctico/administración & dosificación , Macrófagos/citología , Macrófagos/efectos de los fármacos , Ácido Poliglicólico/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificación , Tiofenos/administración & dosificación , Amidas/química , Animales , Neovascularización Coroidal/patología , Modelos Animales de Enfermedad , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Femenino , Ácido Láctico/química , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Inhibidores de Proteínas Quinasas/química , Tiofenos/química
17.
Metab Brain Dis ; 30(4): 943-50, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25604732

RESUMEN

Phagocytic clearance of the spent photoreceptor outer segments (OS) by RPE cells is regulated by circadian rhythm cycle and is essential for photoreceptor integrity and function. Mertk regulates RPE phagocytosis and a deficiency in Mertk causes photoreceptor degeneration and visual loss. This study aimed to investigate Mertk regulation of the microRNAs (miRNA), potentially regulating expression of their target genes, which affect phagocytosis. The differentially expressed miRNAs were identified using miRCURY(TM) microRNA Arrays from total RNA isolated at 0900 h and 1900 h from the mechanically dissociated RPE sheets of the WT and Mertk (-/-) mice, which were housed in a 12-h light-dark cycle with the lighting onset at 0700 h (7:00am). Validation of the differentially expressed miRNAs and assessment of the putative miRNA target gene expression were performed by real-time PCR. Among the differentially expressed miRNAs in the Mertk (-/-) RPE, seven miRNAs were up-regulated and 13 were down-regulated in the morning groups. Similarly, 24 miRNAs were found to be up-regulated and 13 were down-regulated in the evening groups. To search for those that may participate in regulating expression of cytoskeletal proteins, we examined the predicted target genes that might participate in phagocytosis were examined by real-time PCR. Of nine potential altered targets, four deregulated genes were myosin subunits. Notably, multiple members of the 21 up-regulated miRNAs can theoretically recognize these down-regulated mRNAs, particularly MyH14 and Myl3. This study shows that loss of Mertk alters miRNA expression, which in turn affects expression of the downstream target genes, potentially affecting phagocytosis.


Asunto(s)
MicroARNs/biosíntesis , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Tirosina Quinasas Receptoras/deficiencia , Epitelio Pigmentado de la Retina/metabolismo , Animales , Células Cultivadas , Regulación de la Expresión Génica , Ratones , Ratones Noqueados , MicroARNs/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Tirosina Quinasa c-Mer
18.
PLoS One ; 10(1): e0117787, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25617898

RESUMEN

Mertk belongs to the Tyro3, Axl and Mertk (TAM) family of receptor tyrosine kinases, and plays a pivotal role in regulation of cytoskeletal rearrangement during phagocytosis. Phagocytosis by either professional or non-professional phagocytes is impaired in the Mertk deficient individual. In the present study, we further investigated the effects of Mertk mutation on peritoneal macrophage morphology, attachment, spreading and movement. Mertk-mutated macrophages exhibited decreased attachment, weak spreading, loss of spindle-like body shape and lack of clear leading and trailing edges within the first few hours of culture, as observed by environmental scanning electron microscopy. Time-lapse video photography recording showed that macrophage without Mertk conducted mainly random movement with oscillating swing around the cell body, and lost the directional migration action seen on the WT cells. Western blotting showed a decreased phosphorylation of focal adhesion kinase (FAK). Immunocytochemistry revealed that actin filaments and dynamic protein myosin II failed to concentrate in the leading edge of migrating cells. Microtubules were localized mainly in one side of mutant cell body, with no clear MTOC and associated radially-distributed microtubule bundles, which were clearly evident in the WT cells. Our results suggest that Mertk deficiency affects not only phagocytosis but also cell shape and migration, likely through a common regulatory mechanism on cytoskeletons.


Asunto(s)
Movimiento Celular , Citoesqueleto/metabolismo , Macrófagos Peritoneales/citología , Proteínas Proto-Oncogénicas/deficiencia , Proteínas Tirosina Quinasas Receptoras/deficiencia , Animales , Adhesión Celular , Forma de la Célula , Técnicas de Inactivación de Genes , Macrófagos Peritoneales/metabolismo , Ratones , Microtúbulos/metabolismo , Fagocitosis , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Transducción de Señal , Tirosina Quinasa c-Mer
19.
Neural Regen Res ; 10(12): 1976-81, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26889185

RESUMEN

Lycium barbarum is a widely used Chinese herbal medicine prescription for protection of optic nerve. However, it remains unclear regarding the effects of Lycium barbarum polysaccharides, the main component of Lycium barbarum, on in vivo proliferation of adult ciliary body cells. In this study, adult rats were intragastrically administered low- and high-dose Lycium barbarum polysaccharides (1 and 10 mg/kg) for 35 days and those intragastrically administered phosphate buffered saline served as controls. The number of Ki-67-positive cells in rat ciliary body in the Lycium barbarum polysaccharides groups, in particular low-dose Lycium barbarum polysaccharides group, was significantly greater than that in the phosphate buffered saline group. Ki-67-positive rat ciliary body cells expressed nestin but they did not express glial fibrillary acidic protein. These findings suggest that Lycium barbarum polysaccharides can promote the proliferation of adult rat retinal progenitor cells and the proliferated cells present with neuronal phenotype.

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