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2.
Molecules ; 29(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38792047

RESUMEN

Compound 7-16 was designed and synthesized in our previous study and was identified as a more potential selective 5-HT2A receptor antagonist and inverse agonist for treating Parkinson's disease psychosis (PDP). Then, the metabolism, disposition, and excretion properties of 7-16 and its potential inhibition on transporters were investigated in this study to highlight advancements in the understanding of its therapeutic mechanisms. The results indicate that a total of 10 metabolites of 7-16/[14C]7-16 were identified and determined in five species of liver microsomes and in rats using UPLC-Q Exactive high-resolution mass spectrometry combined with radioanalysis. Metabolites formed in human liver microsomes could be covered by animal species. 7-16 is mainly metabolized through mono-oxidation (M470-2) and N-demethylation (M440), and the CYP3A4 isozyme was responsible for both metabolic reactions. Based on the excretion data in bile and urine, the absorption rate of 7-16 was at least 74.7%. 7-16 had weak inhibition on P-glycoprotein and no effect on the transport activity of OATP1B1, OATP1B3, OAT1, OAT3, and OCT2 transporters. The comprehensive pharmacokinetic properties indicate that 7-16 deserves further development as a new treatment drug for PDP.


Asunto(s)
Microsomas Hepáticos , Enfermedad de Parkinson , Humanos , Animales , Ratas , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Microsomas Hepáticos/metabolismo , Antagonistas del Receptor de Serotonina 5-HT2/farmacología , Masculino , Agonistas del Receptor de Serotonina 5-HT2/farmacología
3.
Cell Commun Signal ; 22(1): 225, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38605348

RESUMEN

The endothelial glycocalyx, located at the luminal surface of the endothelium, plays an important role in the regulation of leukocyte adhesion, vascular permeability, and vascular homeostasis. Endomucin (EMCN), a component of the endothelial glycocalyx, is a mucin-like transmembrane glycoprotein selectively expressed by venous and capillary endothelium. We have previously shown that knockdown of EMCN impairs retinal vascular development in vivo and vascular endothelial growth factor 165 isoform (VEGF165)-induced cell migration, proliferation, and tube formation by human retinal endothelial cells in vitro and that EMCN is essential for VEGF165-stimulated clathrin-mediated endocytosis and signaling of VEGF receptor 2 (VEGFR2). Clathrin-mediated endocytosis is an essential step in receptor signaling and is of paramount importance for a number of receptors for growth factors involved in angiogenesis. In this study, we further investigated the molecular mechanism underlying EMCN's involvement in the regulation of VEGF-induced endocytosis. In addition, we examined the specificity of EMCN's role in angiogenesis-related cell surface receptor tyrosine kinase endocytosis and signaling. We identified that EMCN interacts with AP2 complex, which is essential for clathrin-mediated endocytosis. Lack of EMCN did not affect clathrin recruitment to the AP2 complex following VEGF stimulation, but it is necessary for the interaction between VEGFR2 and the AP2 complex during endocytosis. EMCN does not inhibit VEGFR1 and FGFR1 internalization or their downstream activities since EMCN interacts with VEGFR2 but not VEGFR1 or FGFR1. Additionally, EMCN also regulates VEGF121-induced VEGFR2 phosphorylation and internalization.


Asunto(s)
Células Endoteliales , Factor A de Crecimiento Endotelial Vascular , Humanos , Células Endoteliales/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Sialomucinas/metabolismo , Endocitosis , Clatrina/metabolismo
4.
Front Pharmacol ; 14: 1218380, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601058

RESUMEN

Opiates produce analgesia via G-protein signaling, and adverse effects, such as respiratory depression and decreased bowel motility, by ß-arrestin pathway. Oliceridine, a G protein-biased MOR agonist, only presents modest safety advantages as compared to other opiates in clinical trials, possibly due to its limited bias. Our previous study shown that LPM3480392, a full MOR biased agonist, is selective for the Gi pathway over the ß-arrestin-2. In the present article, we evaluated the subacute toxicity of LPM3480392 in rats. The rats were administered with control article or LPM3480392 0.6, 1.2 or 2.4 mg/kg/day for 4 consecutive weeks followed by a 4-week recovery phase. Intravenous infusion was conducted at tail vein at 0.2, 0.4 or 0.8 mg/kg/day with a dosing volume of 10 mL/kg and 5 min/rat/dose, three times a day with an interval of approximately 4 h. The concomitant toxicokinetics study was conducted. Two unscheduled rats at 2.4 mg/kg/day died with no clear cause. For the scheduled necropsy, the major effects were associated with the MOR agonist-related pharmacodynamic properties of LPM3480392 (e.g., increased activity, increased muscle tone; decreased food consumption and body weight gain; and clinical chemistry changes related with decreased food consumption) in three LPM3480392 groups. In addition, LPM3480392 at 2.4 mg/kg/day also induced deep respiration and histopathology changes in testis and epididymis in sporadic individual rats. However, different from other opiates, LPM3480392 presents weak/no immunosuppression and the decreased adrenal gland weight, which may be due to LPM3480392' full MOR bias. At the end of recovery phase, all findings were recovered to some extent or completely. In the toxicokinetics study, the dose-dependent elevation of drug exposure was observed, which partly explained the toxicity of high dose. In summary, LPM3480392 has exhibited good safety characteristics in this subacute toxicity study in rats.

5.
Eur J Med Chem ; 257: 115486, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37247507

RESUMEN

The neurokinin-3 receptor (NK3R) is one of three receptors that recognize neurokinins. The finding that pharmacological blockade of neurokinin B (NKB) signaling with an oral NK3R antagonist can significantly improve hot flash symptoms independent of any hormonal effect fits strongly suggest that NK3R is a viable drug target and that drugs targeting this receptor could be novel pharmacotherapies. Currently no NK3R ligands have been approved for the treatment of human disorders. Herein, we designed and synthesized a series of novel imidazolepiperazine derivatives (16a-16x, 20a-20f, 29a-29m) and performed molecular docking to confirm the design, among which the target compound 16x exhibited promising inhibitory activity against NK3R (IC50 = 430.60 nM) with excellent membrane permeability (Papp, A-B = 37.6 × 10-6 cm/s, ER < 1) and oral bioavailability (F% = 93.6%). Our in vivo studies demonstrated that 16x was orally active, efficacious, and well-tolerated in ovariectomy (OVX) model to suppress blood luteinizing hormone levels, which suggests that 16x is a viable lead compound for further optimization and development.


Asunto(s)
Neuroquinina B , Receptores de Neuroquinina-3 , Femenino , Humanos , Simulación del Acoplamiento Molecular , Transducción de Señal , Ovariectomía
6.
Front Neurorobot ; 17: 1050167, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37033413

RESUMEN

Modern action recognition techniques frequently employ two networks: the spatial stream, which accepts input from RGB frames, and the temporal stream, which accepts input from optical flow. Recent researches use 3D convolutional neural networks that employ spatiotemporal filters on both streams. Although mixing flow with RGB enhances performance, correct optical flow computation is expensive and adds delay to action recognition. In this study, we present a method for training a 3D CNN using RGB frames that replicates the motion stream and, as a result, does not require flow calculation during testing. To begin, in contrast to the SE block, we suggest a channel excitation module (CE module). Experiments have shown that the CE module can improve the feature extraction capabilities of a 3D network and that the effect is superior to the SE block. Second, for action recognition training, we adopt a linear mix of loss based on knowledge distillation and standard cross-entropy loss to effectively leverage appearance and motion information. The Intensified Motion RGB Stream is the stream trained with this combined loss (IMRS). IMRS surpasses RGB or Flow as a single stream; for example, HMDB51 achieves 73.5% accuracy, while RGB and Flow streams score 65.6% and 69.1% accuracy, respectively. Extensive experiments confirm the effectiveness of our proposed method. The comparison with other models proves that our model has good competitiveness in behavior recognition.

7.
Front Plant Sci ; 13: 1022075, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36798802

RESUMEN

Dipsacus asperoides is a perennial herb, the roots of which are abundant in asperosaponin VI, which has important medicinal value. However, the molecular mechanism underlying the biosynthesis of asperosaponin VI in D. asperoides remains unclear. In present study, a comprehensive investigation of asperosaponin VI biosynthesis was conducted at the levels of metabolite and transcript during root development. The content of asperosaponin VI was significantly accumulated in two-leaf stage roots, and the spatial distribution of asperosaponin VI was localized in the xylem. The concentration of asperosaponin VI gradually increased in the root with the development process. Transcriptome analysis revealed 3916 unique differentially expressed genes (DEGs) including 146 transcription factors (TFs) during root development in D. asperoides. In addition, α-linolenic acid metabolism, jasmonic acid (JA) biosynthesis, JA signal transduction, sesquiterpenoid and triterpenoid biosynthesis, and terpenoid backbone biosynthesis were prominently enriched. Furthermore, the concentration of JA gradually increased, and genes involved in α-linolenic acid metabolism, JA biosynthesis, and triterpenoid biosynthesis were up-regulated during root development. Moreover, the concentration of asperosaponin VI was increased following methyl jasmonate (MeJA) treatment by activating the expression of genes in the triterpenoid biosynthesis pathway, including acetyl-CoA acetyltransferase (DaAACT), 3-hydroxy-3-methylglutaryl coenzyme A synthase (DaHMGCS), 3-hydroxy-3-methylglutaryl coenzyme-A reductase (DaHMGCR). We speculate that JA biosynthesis and signaling regulates the expression of triterpenoid biosynthetic genes and facilitate the biosynthesis of asperosaponin VI. The results suggest a regulatory network wherein triterpenoids, JA, and TFs co-modulate the biosynthesis of asperosaponin VI in D. asperoides.

8.
Front Cell Dev Biol ; 9: 734346, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34616740

RESUMEN

Galectin-3 (Gal3) is a carbohydrate-binding protein reported to promote angiogenesis by influencing vascular endothelial growth factor-A receptor 2 (VEGFR2) signal transduction. Here we evaluated whether the ability of Gal3 to function as an angiogenic factor involved vascular endothelial growth factor (VEGF). To address this possibility we used human retinal microvascular endothelial cells (HRECs) to determine whether exogenous Gal3 requires VEGF to activate VEGFR2 signaling and if Gal3 is required for VEGF to activate VEGFR2. VEGFR2 phosphorylation and HREC migration assays, following either VEGF neutralization with ranibizumab or Gal3 silencing, revealed that VEGF endogenously produced by the HRECs was essential for the effect of exogenous Gal3 on VEGFR2 activation and cell migration, and that VEGF-induced VEGFR2 activation was not dependent on Gal3 in HRECs. Gal3 depletion led to no reduction in VEGF-induced cell function. Since Gal3 has been suggested to be a potential therapeutic target for VEGFR2-mediated angiogenesis, it is crucial to define the possible Gal3-mediated VEGFR2 signal transduction mechanism to aid the development of efficacious therapeutic strategies.

9.
Front Cell Dev Biol ; 9: 734276, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34532323

RESUMEN

The endothelial glycocalyx is a negatively charged, carbohydrate-rich structure that arises from the luminal surface of the vascular endothelium and is comprised of proteoglycans, glycoproteins, and glycolipids. The glycocalyx, which sits at the interface between the endothelium and the blood, is involved in a wide array of physiological and pathophysiological processes, including as a mechanotransducer and as a regulator of inflammation. Most recently, components of the glycocalyx have been shown to play a key role in controlling angiogenesis. In this review, we briefly summarize the structure and function of the endothelial glycocalyx. We focus on its role and functions in vascular inflammation and angiogenesis and discuss the important unanswered questions in this field.

10.
BMC Ophthalmol ; 21(1): 56, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33482759

RESUMEN

BACKGROUND: Sturge-Weber syndrome is a disorder marked by a distinctive facial capillary malformation, neurological abnormalities, and ocular abnormalities such as glaucoma and choroidal hemangioma. CASE PRESENTATION: We report a case of progressively formed retinal vessel malformation in a premature male infant with Sturge-Weber syndrome and retinopathy of prematurity, after treatment with intravitreal anti-vascular endothelial growth factor (VEGF). The baby was born at 30 weeks gestation with a nevus flammeus involving his left eyelids and maxillary area. On postmenstrual age week 39, he received intravitreal anti-VEGF. Diffuse choroidal hemangioma became evident at 40 weeks, with the classic "tomato catsup fundus" appearance. These clinical findings characterized Sturge-weber syndrome. He presented with posterior retinal vessel tortuosity and vein-to-vein anastomoses at 44 weeks. CONCLUSION: This is a rare case of documented progression of retinal vessel malformations in a patient with Sturge-Weber syndrome and retinopathy of prematurity.


Asunto(s)
Neoplasias de la Coroides , Hemangioma , Síndrome de Sturge-Weber , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Masculino , Vasos Retinianos , Síndrome de Sturge-Weber/complicaciones , Síndrome de Sturge-Weber/diagnóstico
11.
Int J Mol Sci ; 21(21)2020 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-33147690

RESUMEN

Connexins are the structural components of gap junctions and hemichannels that mediate the communication and exchange of small molecules between cells, and between the intracellular and extracellular environment, respectively. Connexin (Cx) 46 is predominately expressed in lens fiber cells, where they function in maintaining the homeostasis and transparency of the lens. Cx46 mutations are associated with impairment of channel function, which results in the development of congenital cataracts. Cx46 gap junctions and hemichannels are closely regulated by multiple mechanisms. Key regulators of Cx46 channel function include Ca2+ and calmodulin (CaM). Ca2+ plays an essential role in lens homeostasis, and its dysregulation causes cataracts. Ca2+ associated CaM is a well-established inhibitor of gap junction coupling. Recent studies suggest that elevated intracellular Ca2+ activates Cx hemichannels in lens fiber cells and Cx46 directly interacts with CaM. A Cx46 site mutation (Cx46-G143R), which is associated with congenital Coppock cataracts, shows an increased Cx46-CaM interaction and this interaction is insensitive to Ca2+, given that depletion of Ca2+ reduces the interaction between CaM and wild-type Cx46. Moreover, inhibition of CaM function greatly reduces the hemichannel activity in the Cx46 G143R mutant. These research findings suggest a new regulatory mechanism by which enhanced association of Cx46 with CaM leads to the increase in hemichannel activity and dysregulation may lead to cataract development. In this review, we will first discuss the involvement of Ca2+/CaM in lens homeostasis and pathology, and follow by providing a general overview of Ca2+/CaM in the regulation of Cx46 gap junctions. We discuss the most recent studies concerning the molecular mechanism of Ca2+/CaM in regulating Cx46 hemichannels. Finally, we will offer perspectives of the impacts of Ca2+/CaM and dysregulation on Cx46 channels and vice versa.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Calcio/metabolismo , Calmodulina/metabolismo , Conexinas/metabolismo , Uniones Comunicantes/metabolismo , Cristalino/metabolismo , Animales , Regulación de la Expresión Génica , Homeostasis , Humanos , Mutación , Estructura Secundaria de Proteína
12.
Cells ; 9(6)2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32517158

RESUMEN

Endomucin (EMCN) is the type I transmembrane glycoprotein, mucin-like component of the endothelial cell glycocalyx. We have previously shown that EMCN is necessary for vascular endothelial growth factor (VEGF)-induced VEGF receptor 2 (VEGFR2) internalization and downstream signaling. To explore the structural components of EMCN that are necessary for its function and the molecular mechanism of EMCN in VEGF-induced endothelial functions, we generated a series of mouse EMCN truncation mutants and examined their ability to rescue VEGF-induced endothelial functions in human primary endothelial cells (EC) in which endogenous EMCN had been knocked down using siRNA. Expression of the mouse full-length EMCN (FL EMCN) and the extracellular domain truncation mutants ∆21-81 EMCN and ∆21-121 EMCN, but not the shortest mutant ∆21-161 EMCN, successfully rescued the VEGF-induced EC migration, tube formation, and proliferation. ∆21-161 EMCN failed to interact with VEGFR2 and did not facilitate VEGFR2 internalization. Deletion of COSMC (C1GalT1C1) revealed that the abundant mucin-type O-glycans were not required for its VEGFR2-related functions. Mutation of the two N-glycosylation sites on ∆21-121 EMCN abolished its interaction with VEGFR2 and its function in VEGFR2 internalization. These results reveal ∆21-121 EMCN as the minimal extracellular domain sufficient for VEGFR2-mediated endothelial function and demonstrate an important role for N-glycosylation in VEGFR2 interaction, internalization, and angiogenic activity.


Asunto(s)
Sialomucinas/química , Sialomucinas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Secuencia de Aminoácidos , Endocitosis , Glicosilación , Humanos , Mutación/genética , Dominios Proteicos , Sialomucinas/genética , Transducción de Señal
13.
Toxicol Appl Pharmacol ; 398: 115019, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32335126

RESUMEN

The non-receptor tyrosine phosphatase SHP2, encoded by PTPN11, plays an indispensable role in tumors driven by oncogenic KRAS mutations, which frequently occur in colorectal cancer. Here, PCC0208023, a potent SHP2 allosteric inhibitor, was synthesized to evaluate its inhibitory effects against the SHP2 enzyme, and the KRAS mutant colorectal cancer in vitro and in vivo, and its impart on the RAS/MAPK pathway. Consistent with an allosteric mode of inhibition, PCC0208023 can non-competitively inhibit the activity of full-length SHP2 enzyme, but lacks activity against the free catalytic domain of SHP2. Furthermore, PCC0208023 inhibited the proliferation of KRAS mutation-driven human colorectal cancer cells by inhibiting the RAS/MAPK signaling pathway in vitro. Importantly, PCC0208023 displayed good anti-tumor efficacy against KRAS-driven LS180 and HCT116 xenograft models in nude mice with the decreased Ki67 and p-ERK level, and increased cleaved caspase-3 expression in tumors. Interestingly, PCC0208023 maintained high levels in LS180 tumors within 24 h after administration and was mainly distributed in both intestines and lungs. Molecular docking studies revealed a higher affinity of PCC0208023 with key residues in the SHP2 allosteric pocket than RMC-4550. PCC0208023 deserves further optimization to identify additional low-toxic and potent SHP2 allosteric inhibitors with novel scaffolds for the treatment of patients with KRAS mutation-positive colorectal cancer.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Mutación/efectos de los fármacos , Proteína Tirosina Fosfatasa no Receptora Tipo 11/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/genética , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/metabolismo , Femenino , Células HCT116 , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Mutación/genética , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
14.
PLoS One ; 15(3): e0228339, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32214351

RESUMEN

The increased PD-L1 expression induces poorer prognosis in melanoma. The small molecule inhibitors of PD-1/PD-L1 pathways have been an encouraging drug development strategy because of good affinity and oral bioavailability without immunogenicity and immunotoxicities of PD-1/PD-L1 antibodies. In this study, we studied the effects of PCC0208025 (BMS202), a small molecule inhibitor of PD-L1, on PD-1/PD-L1 binding and the cytokines secretion in human CD3+ cells in vitro. We also investigated the antitumor and immunomodulatory activity of PCC0208025 and the pharmacokinetics properties in B16-F10 melanoma-bearing mice. The results showed that PCC0208025 inhibited the PD-1/PD-L1 proteins binding, and rescued PD-L1-mediated inhibition of IFN-γ production in human CD3+ T cells in vitro. Furthermore, in B16-F10 melanoma-bearing mice, PCC0208025 presented the antitumor effects, enhanced IFN-γ levels in plasma, increased the frequency of CD3+CD8+ T and CD8+IFN-γ+ T and the ratios of CD8+/Treg, and deceased the CD4+CD25+CD127low/- (Treg) number in tumor. Pharmacokinetics study found that PCC0208025 was absorbed and distributed into the tumors with much higher concentrations than those of the blockade against PD-1/PD-L1 binding. Our work suggests that PCC0208025 exhibited anti-tumor effects through inhibiting Treg expansion and increasing cytotoxic activity of tumor-infiltrating CD8+ T cells by the blockade of PD-1/PD-L1 binding, which may provide the pharmacological basis to develop small molecule inhibitors of PD-1/PD-L1 binding for PCC0208025 as a lead compound.


Asunto(s)
Acetamidas/farmacología , Antineoplásicos/farmacología , Antígeno B7-H1/antagonistas & inhibidores , Melanoma Experimental/tratamiento farmacológico , Piridinas/farmacología , Bibliotecas de Moléculas Pequeñas/farmacología , Acetamidas/farmacocinética , Acetamidas/uso terapéutico , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Humanos , Factores Inmunológicos/farmacocinética , Factores Inmunológicos/farmacología , Factores Inmunológicos/uso terapéutico , Interferón gamma/metabolismo , Masculino , Melanoma Experimental/patología , Ratones , Piridinas/farmacocinética , Piridinas/uso terapéutico , Bibliotecas de Moléculas Pequeñas/farmacocinética , Bibliotecas de Moléculas Pequeñas/uso terapéutico
15.
Lab Invest ; 99(12): 1874-1886, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31439892

RESUMEN

Epithelial to mesenchymal transition (EMT) plays an important role in the pathogenesis of proliferative vitreoretinopathy (PVR). We aimed to demonstrate the role of mouse double minute 2 (MDM2) in transforming growth factor-beta 2 (TGF-ß2)-induced EMT in human retinal pigment epithelial cells (RPEs). Immunofluorescence was used to assess MDM2 expression in epiretinal membranes (ERMs) from patients with PVR. A single guide (sg)RNA targeting the second promoter of MDM2 was cloned into a mutant lentiviral Clustered Regularly Interspaced Short Palindromic Repeats (lentiCRISPR) v2 (D10A and H840A) vector for expressing nuclease dead Cas9 (dCas9)/MDM2-sgRNA in RPEs. In addition, MDM2-sgRNA was also cloned into a pLV-sgRNA-dCas9-Kruppel associated box (KRAB) vector for expressing dCas9 fused with a transcriptional repressor KRAB/MDM2-sgRNA. TGF-ß2-induced expression of MDM2 and EMT biomarkers were assessed by quantitative polymerase chain reaction (q-PCR), western blot, or immunofluorescence. Wound-healing and proliferation assays were used to evaluate the role of MDM2 in TGF-ß2-induced responses in RPEs. As a result, we found that MDM2 was expressed obviously in ERMs, and that TGF-ß2-induced expression of MDM2 and EMT biomarkers Fibronectin, N-cadherin and Vimentin in RPEs. Importantly, we discovered that the dCas9/MDM2-sgRNA blocked TGF-ß2-induced expression of MDM2 and the EMT biomarkers without affecting their basal expression, whereas the dCas9-KRAB/MDM2-sgRNA suppressed basal MDM2 expression in RPEs. These cells could not be maintained continuously because their viability was greatly reduced. Next, we found that Nutlin-3, a small molecule blocking the interaction of MDM2 with p53, inhibited TGF-ß2-induced expression of Fibronectin and N-cadherin but not Vimentin in RPEs, indicating that MDM2 functions in both p53-dependent and -independent pathways. Finally, our experimental data demonstrated that dCas9/MDM2-sgRNA suppressed TGF-ß2-dependent cell proliferation and migration without disturbing the unstimulated basal activity. In conclusion, the CRISPR/dCas9 capability for blocking TGF-ß2-induced expression of MDM2 and EMT biomarkers can be exploited for a therapeutic approach to PVR.


Asunto(s)
Transición Epitelial-Mesenquimal , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Vitreorretinopatía Proliferativa/etiología , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Membrana Epirretinal/metabolismo , Células HEK293 , Humanos , Proteínas Proto-Oncogénicas c-mdm2/antagonistas & inhibidores , Epitelio Pigmentado de la Retina/citología , Factor de Crecimiento Transformador beta2 , Vitreorretinopatía Proliferativa/metabolismo , Vitreorretinopatía Proliferativa/terapia
16.
Exp Eye Res ; 186: 107716, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31278903

RESUMEN

Mouse double minute (MDM)2 single nucleotide polymorphism (SNP) 309G allele in the second promoter of MDM2 enhances vitreous-induced expression of Mdm2 and degradation of the tumor suppressor protein p53. This MDM2SNP309G contributes to certain cancer development and experimental proliferative vitreoretinopathy. The goal of this study is to discover a novel strategy to only block vitreous-induced expression of Mdm2 for preventing vitreous-induced cell proliferation and survival and thus find a potential novel strategy to treat proliferation-related diseases. We created two mutations (D10A and H840A) in Streptococcus pyogenes (Sp)Cas9 within the nuclease domains (RuvC1 and HNH, respectively) to render this SpCas9 nuclease dead named as dCas9 in a lentiCRISPR v2 vector. Then an MDM2-sgRNA targeting the second promoter of human MDM2 gene was cloned into this vector for producing lentivirus to infect human retinal pigment epithelial (RPE) cells with, which carry a heterozygous genotype of MDM2SNP309 T/G. lacZ-sgRNA was used as a control. As a result, we discovered that vitreous from experimental rabbits induced a 1.9 ±â€¯0.2 fold increase in Mdm2 and a 2.0 ±â€¯0.2 fold decrease in p53 in the RPE cells with dCas9/lacZ-sgRNA compared to those with dCas9/MDM2-sgRNA, suggesting that dCas9 under the guidance of the MDM2-sgRNA prevented RV-stimulated increase in Mdm2. In addition, we found that the rabbit vitreous significantly enhanced cell proliferation (1.5 ±â€¯0.2 fold), survival against apoptosis (2.2 ±â€¯0.2 fold), migration (10 ±â€¯1.5%) and contraction (112.7 ±â€¯14.1 mm2) of the cells with dCas9/lacZ-sgRNA compared with those with dCas9/MDM2-sgRNA. These results indicated that application of the dCas9 targeted to the P2 of MDM2 is a potential therapeutic approach to diseases due to the P2-driven aberrant expression of Mdm2 - such as proliferative vitreoretinopathy.


Asunto(s)
Sistemas CRISPR-Cas/fisiología , Células Epiteliales/fisiología , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Epitelio Pigmentado de la Retina/fisiología , Cuerpo Vítreo/metabolismo , Animales , Proliferación Celular/fisiología , Supervivencia Celular/fisiología , Células Cultivadas , Humanos , Ratones , Terapia Molecular Dirigida/métodos , Polimorfismo de Nucleótido Simple , Proteína p53 Supresora de Tumor/metabolismo , Vitreorretinopatía Proliferativa/fisiopatología
17.
BMC Ophthalmol ; 19(1): 164, 2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31357978

RESUMEN

BACKGROUND: To investigate the long-term outcomes and complications of scleral-fixated intraocular lens (SFIOL) implantation without conjunctival peritomies and sclerotomy in patients with a history of ocular trauma with inadequate capsular support during primary pars plana vitrectomy or silicone oil removal. METHODS: Records of ocular trauma patients who underwent implantation of SFIOL without conjunctival peritomies and sclerotomy during primary pars plana vitrectomy or silicone oil removal. RESULTS: Sixty-nine eyes of 69 patients were included in this study. The median follow-up period was 34 months (range, 6-99 months). The average patient age at the time of surgery was 44 years old (range, 4-80 years). At the end of follow-up, the preoperative mean of best corrected visual acuity (BCVA) was 0.79 ± 0.86 log of the minimum angle of resolution (logMAR), which improved 0.20 ± 0.26 logMAR postoperatively (P = 0.01). BCVA improved or remained unchanged in 64 eyes (92.8%), VA decreased two lines in five eyes (7.2%). Early postoperative complications included transient corneal edema in seven eyes (10.1%), minor vitreous hemorrhage in four eyes (5.8%), transient elevated intraocular pressure (IOP) in one eye (1.4%), and hypotony in three eyes (4.3%). Late postoperative complications included persistent elevated IOP in five eyes (7.2%), epiretinal membrane formation in three eyes (4.3%), and cystoid macular edema noted in one eye (1.4%). CONCLUSIONS: Use of a scleral-fixated intraocular lens implantation without conjunctival peritomies and sclerotomy in ocular trauma patients during either primary pars plana vitrectomy or second silicone oil removal is a valuable approach for the management of traumatic aphakia in the absence of capsular support.


Asunto(s)
Afaquia/cirugía , Lesiones Oculares/complicaciones , Implantación de Lentes Intraoculares/métodos , Esclerótica/cirugía , Técnicas de Sutura , Agudeza Visual , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Afaquia/diagnóstico , Afaquia/etiología , Niño , Preescolar , Conjuntiva , Lesiones Oculares/diagnóstico , Lesiones Oculares/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Vitrectomía , Adulto Joven
18.
FASEB J ; 33(8): 9362-9373, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31141406

RESUMEN

We have previously shown that knockdown of endomucin (EMCN), an integral membrane glycocalyx glycoprotein, prevents VEGF-induced proliferation, migration, and tube formation in vitro and angiogenesis in vivo. In the endothelium, VEGF mediates most of its angiogenic effects through VEGF receptor 2 (VEGFR2). To understand the role of EMCN, we examined the effect of EMCN depletion on VEGFR2 endocytosis and activation. Results showed that although VEGF stimulation promoted VEGFR2 internalization in control endothelial cells (ECs), loss of EMCN prevented VEGFR2 endocytosis. Cell surface analysis revealed a decrease in VEGFR2 following VEGF stimulation in control but not siRNA directed against EMCN-transfected ECs. EMCN depletion resulted in heightened phosphorylation following VEGF stimulation with an increase in total VEGFR2 protein. These results indicate that EMCN modulates VEGFR2 endocytosis and activity and point to EMCN as a potential therapeutic target.-LeBlanc, M. E., Saez-Torres, K. L., Cano, I., Hu, Z., Saint-Geniez, M., Ng, Y.-S., D'Amore, P. A. Glycocalyx regulation of vascular endothelial growth factor receptor 2 activity.


Asunto(s)
Glicocálix/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adenoviridae/genética , Línea Celular , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Endocitosis/efectos de los fármacos , Endocitosis/genética , Endocitosis/fisiología , Humanos , Fosforilación/efectos de los fármacos , Sialomucinas/genética , Sialomucinas/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
19.
Int J Immunopathol Pharmacol ; 33: 2058738419843366, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30968715

RESUMEN

Poor prognosis is associated with melanoma due to immunosuppression profiles, suggesting that immune alterations have an important role in the occurrence, growth, and metastasis of melanoma. Here, we found that PCC0208018, a small-molecule compound, enhanced T cell proliferation and activation to release interferon gamma (IFN-γ) and interleukin-2 (IL-2) without blocking the programmed cell death 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) binding and did not directly affect tumor cell viability in vitro. Furthermore, PCC0208018 increased the phosphorylation of protein kinase B (PKB/AKT) as well as extracellular regulated protein kinases (ERK) in human peripheral blood mononuclear cells (PBMCs) in vitro. The secretion of cytokines induced by PCC0208018 was significantly suppressed by the PI3K inhibitor GDC-0941. In B16-F10 melanoma-harboring mice, PCC0208018 significantly inhibited tumor growth as well as increasing CD3+, CD3+CD4+, and CD3+CD8+ T cell abundance in tumors without affecting PD-L1 expression. This study showed that PCC0208018 potentially increased PBMCs proliferation and function by activating the phosphatidylinositol 3 kinase (PI3K)/AKT and mitogen-activated protein kinase (MEK)/ERK pathways to exert antitumor effects.


Asunto(s)
Antineoplásicos/farmacología , Melanoma Experimental/metabolismo , Neoplasias Cutáneas/metabolismo , Linfocitos T/metabolismo , Animales , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Células CHO , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Células Cultivadas , Cricetinae , Cricetulus , Humanos , Masculino , Melanoma Experimental/tratamiento farmacológico , Ratones , Ratones Endogámicos C57BL , Neoplasias Cutáneas/tratamiento farmacológico , Ensayos Antitumor por Modelo de Xenoinjerto
20.
J Biol Chem ; 293(7): 2573-2585, 2018 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-29298900

RESUMEN

Connexin channels help maintain eye lens homeostasis and transparency. The G143R missense substitution in connexin (Cx) 46 is associated with congenital Coppock cataracts; however, the underlying molecular mechanism is largely unknown. Here, we report that compared with WT Cx46, the G143R substitution abolishes hemichannel conductance in Xenopus oocytes and in HeLa cells. Moreover, this substitution is dominant-negative and inhibits conductance of WT Cx46. CD analysis indicated that the substitution greatly reduces the α-helical structure of the intracellular Cx46 loop domain. Protein pulldown assays and isothermal titration calorimetry revealed that this Cx46 domain directly interacts with calmodulin (CaM) in a Ca2+-dependent fashion, an observation confirmed by immunofluorescent co-localization of Cx46 with CaM. Interestingly, the G143R substitution enhanced the Cx46-CaM interaction and attenuated its abolishment by Ca2+ depletion. Moreover, Cx46 increased dye influx, and the G143R substitution augmented this effect. Inhibition of Ca2+-mediated CaM activation blocked hemichannel permeability. The membrane potential plays a crucial role in Cx46 membrane permeability. We found that the activity of hemichannels is detectable under rest and hyperpolarization conditions but is eliminated with depolarization. These results suggested that the G143R substitution impairs voltage-dependent electrical conductance and alters membrane permeability mediated by Cx46 hemichannels. The latter likely is caused by the substitution-induced structural changes of the intracellular loop domain associated with the increased interaction with CaM and reduced Ca2+ sensitivity. The data suggest that the G143R-induced enhancement of the CaM-Cx46 interaction results in altered hemichannel activities and might be related to cataract formation.


Asunto(s)
Calmodulina/metabolismo , Catarata/genética , Conexinas/genética , Mutación Missense , Animales , Calcio/metabolismo , Calmodulina/química , Calmodulina/genética , Catarata/congénito , Catarata/metabolismo , Conexinas/química , Conexinas/metabolismo , Femenino , Uniones Comunicantes/metabolismo , Células HeLa , Humanos , Cristalino/metabolismo , Potenciales de la Membrana , Oocitos/química , Oocitos/metabolismo , Unión Proteica , Dominios Proteicos , Xenopus
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