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1.
J Hepatol ; 78(4): 770-782, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36708811

RESUMO

BACKGROUND & AIMS: The tumour microenvironment (TME) is a crucial mediator of cancer progression and therapeutic outcome. The TME subtype correlates with patient response to immunotherapy in multiple cancers. Most previous studies have focused on the role of different cellular components in the TME associated with immunotherapy efficacy. However, the specific structure of the TME and its role in immunotherapy efficacy remain largely unknown. METHODS: We combined spatial transcriptomics with single-cell RNA-sequencing and multiplexed immunofluorescence to identify the specific spatial structures in the TME that determine the efficacy of immunotherapy in patients with hepatocellular carcinoma (HCC) receiving anti-PD-1 treatment. RESULTS: We identified a tumour immune barrier (TIB) structure, a spatial niche composed of SPP1+ macrophages and cancer-associated fibroblasts (CAFs) located near the tumour boundary, which is associated with the efficacy of immune checkpoint blockade. Furthermore, we dissected ligand‒receptor networks among malignant cells, SPP1+ macrophages, and CAFs; that is, the hypoxic microenvironment promotes SPP1 expression, and SPP1+ macrophages interact with CAFs to stimulate extracellular matrix remodelling and promote TIB structure formation, thereby limiting immune infiltration in the tumour core. Preclinically, the blockade of SPP1 or macrophage-specific deletion of Spp1 in mice led to enhanced efficacy of anti-PD-1 treatment in mouse liver cancer, accompanied by reduced CAF infiltration and increased cytotoxic T-cell infiltration. CONCLUSIONS: We identified that the TIB structure formed by the interaction of SPP1+ macrophages and CAFs is related to immunotherapy efficacy. Therefore, disruption of the TIB structure by blocking SPP1 may be considered a relevant therapeutic approach to enhance the therapeutic effect of immune checkpoint blockade in HCC. IMPACT AND IMPLICATIONS: Only a limited number of patients with hepatocellular carcinoma (HCC) benefit from tumour immunotherapy, which significantly hinders its application. Herein, we used multiomics to identify the spatial structure of the tumour immune barrier (TIB), which is formed by the interaction of SPP1+ macrophages and cancer-associated fibroblasts in the HCC microenvironment. This structure constrains immunotherapy efficacy by limiting immune cell infiltration into malignant regions. Preclinically, we revealed that blocking SPP1 or macrophage-specific deletion of Spp1 in mice could destroy the TIB structure and sensitize HCC cells to immunotherapy. These results provide the first key steps towards finding more effective therapies for HCC and have implications for physicians, scientists, and drug developers in the field of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Microambiente Tumoral , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia/métodos
2.
Rev Endocr Metab Disord ; 22(2): 205-216, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33761053

RESUMO

In diabetic patients, diabetic retinopathy (DR) is the leading cause of blindness and seriously affects the quality of life. However, current treatment methods of DR are not satisfactory. Advances have been made in understanding abnormal protein interactions and signaling pathways in DR pathology, but little is known about epigenetic regulation. Non-coding RNAs, such as circular RNAs (circRNAs), have been shown to be associated with DR. In this review, we summarized the function of circRNAs and indicated their roles in the pathogenesis of DR, which may provide new therapeutic targets for clinical treatment.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Retinopatia Diabética/genética , Epigênese Genética , Humanos , Qualidade de Vida , RNA Circular , Transdução de Sinais
3.
Exp Eye Res ; 202: 108300, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065089

RESUMO

Diabetic retinopathy (DR) is the leading cause of visual impairment and acquired blindness among adults worldwide. Retinal microvascular pericyte deficiency is one of the earliest pathological changes associated with DR, and long noncoding RNA myocardial infarction-associated transcript (MIAT) has been implicated as a crucial regulator of microvascular dysfunction in DR. Pyroptosis is a caspase-1-dependent proinflammatory form of cell death, and in the present study, we investigated the potential pyroptosis of primary human retinal pericytes (HRPCs) and the mechanism by which MIAT is involved in this process. We applied advanced glycation end product modified bovine serum albumin (AGE-BSA) to simulate the DR environment. The results suggested that AGE-BSA induced the active cleavage of caspase-1 and gasdermin D, the release of IL-1ß, IL-18 and LDH, and reduced cell viability, which was prevented by the inhibition of caspase-1, indicating the occurrence of caspase-1-mediated pyroptosis in HRPCs. Immunofluorescence images revealed the phenotypic characteristics of pyroptosis, including pyknosis, swelling and hyperpermeability in plasmolemma. MIAT and CASP1 expression were substantially increased, while that of miR-342-3p was decreased in AGE-BSA-treated HRPCs. MIAT knockdown inhibited pyroptosis in HRPCs, which was reinforced by cotreatment with miR-342-3p mimic but relieved by cotreatment with miR-342-3p inhibitor. Furthermore, HRPC pyroptosis was inhibited by treatment with the miR-342-3p mimic alone but enhanced by the miR-342-3p inhibitor. Luciferase reporter assay results demonstrated binding between MIAT and miR-342-3p, as well as between miR-342-3p and CASP1. MIAT antagonized the effect of miR-342-3p on the depression of its target CASP1 and promoted AGE-BSA-induced pericyte pyroptosis. These findings may promote a better understanding of retinal pericyte depletion pathogenesis and the development of new therapeutic strategies for the treatment of diabetic retinopathy.


Assuntos
Caspase 1/metabolismo , Retinopatia Diabética/metabolismo , MicroRNAs/metabolismo , Pericitos/fisiologia , Piroptose/fisiologia , RNA Longo não Codificante/fisiologia , Vasos Retinianos/citologia , Western Blotting , Sobrevivência Celular/fisiologia , Células Cultivadas , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica/fisiologia , Genes Reporter/genética , Humanos , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
4.
Adv Sci (Weinh) ; : e2309885, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956900

RESUMO

Although hypoxia is known to be associated with immune resistance, the adaptability to hypoxia by different cell populations in the tumor microenvironment and the underlying mechanisms remain elusive. This knowledge gap has hindered the development of therapeutic strategies to overcome tumor immune resistance induced by hypoxia. Here, bulk, single-cell, and spatial transcriptomics are integrated to characterize hypoxia associated with immune escape during carcinogenesis and reveal a hypoxia-based intercellular communication hub consisting of malignant cells, ALCAMhigh macrophages, and exhausted CD8+ T cells around the tumor boundary. A hypoxic microenvironment promotes binding of HIF-1α complex is demonstrated to the ALCAM promoter therefore increasing its expression in macrophages, and the ALCAMhigh macrophages co-localize with exhausted CD8+ T cells in the tumor spatial microenvironment and promote T cell exhaustion. Preclinically, HIF-1ɑ inhibition reduces ALCAM expression in macrophages and exhausted CD8+ T cells and potentiates T cell antitumor function to enhance immunotherapy efficacy. This study reveals the systematic landscape of hypoxia at single-cell resolution and spatial architecture and highlights the effect of hypoxia on immunotherapy resistance through the ALCAMhigh macrophage-exhausted T cell axis, providing a novel immunotherapeutic strategy to overcome hypoxia-induced resistance in cancers.

5.
Nat Commun ; 15(1): 5209, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890388

RESUMO

Despite the importance of spliceosome core components in cellular processes, their roles in cancer development, including hepatocellular carcinoma (HCC), remain poorly understood. In this study, we uncover a critical role for SmD2, a core component of the spliceosome machinery, in modulating DNA damage in HCC through its impact on BRCA1/FANC cassette exons and expression. Our findings reveal that SmD2 depletion sensitizes HCC cells to PARP inhibitors, expanding the potential therapeutic targets. We also demonstrate that SmD2 acetylation by p300 leads to its degradation, while HDAC2-mediated deacetylation stabilizes SmD2. Importantly, we show that the combination of Romidepsin and Olaparib exhibits significant therapeutic potential in multiple HCC models, highlighting the promise of targeting SmD2 acetylation and HDAC2 inhibition alongside PARP inhibitors for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Éxons , Neoplasias Hepáticas , Ftalazinas , Piperazinas , Inibidores de Poli(ADP-Ribose) Polimerases , Spliceossomos , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Acetilação , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Spliceossomos/metabolismo , Spliceossomos/efeitos dos fármacos , Linhagem Celular Tumoral , Ftalazinas/farmacologia , Éxons/genética , Piperazinas/farmacologia , Animais , Proteína BRCA1/metabolismo , Proteína BRCA1/genética , Depsipeptídeos/farmacologia , Depsipeptídeos/uso terapêutico , Camundongos , Dano ao DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
6.
Bioengineered ; 13(4): 9916-9927, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35412937

RESUMO

Retinal pigment epithelium (RPE) is an important component of the outer blood-retinal barrier and plays a critical role in maintaining retinal homeostasis. Alterations in RPE can be detected during the early stages of diabetic retinopathy (DR). However, the molecular mechanisms underlying these early changes remain unclear. We investigated the molecular changes induced in the RPE by high glucose concentrations by constructing a high glucose-induced ARPE-19 cell injury model simulating the DR environment in vitro. Proteomic analysis was conducted to measure differences in protein expression between cells treated with normal (5 mM) and high (25 mM) glucose concentrations, and bioinformatics techniques were used to analyze the mechanism of action. The results of the proteomic analyses were validated using western blotting. High glucose levels inhibited the proliferation of ARPE-19 cells. We identified 88 upregulated proteins and 114 downregulated proteins. Six of these proteins were selected for further validation. Changes in the proteome mainly affected the lysosome and cell cycle pathways. Proteomic differences between ARPE-19 cells treated with normal and high glucose concentrations indicate that damage to the RPE in DR may be caused by specific mechanisms. Our study verified protein changes in ARPE-19 cells in a high-glucose environment and may provide new strategies for understanding the molecular mechanisms underlying DR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Glucose/metabolismo , Glucose/farmacologia , Humanos , Proteoma , Proteômica , Epitélio Pigmentado da Retina
7.
ChemSusChem ; 15(13): e202200352, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35575041

RESUMO

5-hydroxymethylfurfural (HMF) is considered to be one of the most pivotal multifunctional biomass platform chemicals. This Review discusses recent advances in catalytic oxidation of HMF towards high-value products. The reaction mechanism of different noble metals and the path of HMF oxidation to high-value products have been deeply investigated in the noble metal catalytic system. The reaction mechanisms of different noble metals and HMF conversion paths were compared in detail. Moreover, the factors affecting the performance of different noble metal catalysts were summarized. Finally, effective strategies were put forward to improve the catalytic performance of noble metal catalysts. The purpose is to provide a valuable reference for the academic research on the preparation of oxidation products from biomass-based HMF and the industrial application of noble metal catalysts.


Assuntos
Furaldeído , Metais , Catálise , Furaldeído/análogos & derivados , Oxirredução
8.
Front Endocrinol (Lausanne) ; 13: 1052794, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36465621

RESUMO

Objective: This study aims to investigate the effect of single urine C peptide/creatinine (UCPCR) in assessing the islet ß Cell function of type 2 diabetes mellitus (T2DM) patients with different renal function. Methods: A total of 85 T2DM patients were recruited in this study, all the patients were assigned to one group with estimated glomerular filtration rate (eGFR)≤60 ml·min-1·1.73 m-2 and another group complicated with eGFR>60 ml·min-1·1.73 m-2. Serum creatinine, urine creatinine, serum fasting C-peptide (FCP), fasting blood glucose (FBG), glycosylated hemoglobin (HbA1C) and 24-hour urinary C-peptide (24hUCP) were measured. The modified homeostasis model assessment-islet ß cell function [HOMA-islet (CP-DM)], the modified homeostasis model assessment-insulin resistance [HOMA-IR(CP)] and UCPCR were calculated. Results: When compared with group eGFR ≤60 ml·min-1·1.73 m-2, the levels of UCPCR, FCP, the modified HOMA-IR(CP) and HOMA-islet (CP-DM) were promoted and the concentrations of HbA1C, FPG, creatinine were decreased in the patients of eGFR>60 ml·min-1·1.73 m-2 (P<0.05); FCP was uncorrelated with 24hUCP while associated with UCPCR in the patients of eGFR ≤ 60 ml·min-1·1.73 m-2; UCPCR was positively correlated with FCP and HOMA-IR(CP) in the T2DM patients with different levels of renal function; the cut-off (UCPCR ≤ 1.13 nmol/g) had 88.37% sensitivity and 95.24% specificity [95% confidence interval (CI):0.919-0.997] for identifying severe insulin deficiency in T2DM patients[area under the curve (AUC) 0.978]. Conclusion: UCPCR can be used to evaluate islets ß Cell function in T2DM patients with different renal function status.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Peptídeo C , Creatinina , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Rim/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-36569344

RESUMO

Retinal pericyte migration occurs in the early stage of diabetic retinopathy (DR), which is one of the important causes of pericyte loss. Autophagy has been found to play essential roles in the regulation of many types of cell migration. In this study, we explored the relationship between autophagy and retinal pericyte migration. In diabetic rats, the retinas became thinner, and the level of autophagy in each cell layer increased. In the primary culture of bovine retinal pericytes, we found that advanced glycation end products (AGEs) increased the migratory cell ability without influencing cell viability, which also increased the phosphorylation of focal adhesion kinase (FAK) and the expression of matrix metalloproteinase (MMP)-2 and decreased the expression of vinculin. AGEs-induced retinal pericyte autophagy and the inhibition of autophagy with chloroquine significantly inhibited cell migration, reversed AGEs-induced FAK phosphorylation, and changed vinculin and MMP-2 protein expression. These results provide a new insight into the migration mechanism of retinal pericytes. The early control of autophagy has a potential effect on regulating pericyte migration, which may contribute to keeping the integrity of retinal vessels in DR.

10.
Cell Death Dis ; 13(7): 623, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851063

RESUMO

The incidence of hepatocellular carcinoma (HCC) is increasing in the world. However, its role and underlying molecular mechanism in HCC progression remain unclear. We found that CYB5A plays a key role in HCC metastasis by inhibiting the JAK1/STAT3 pathway through binding to STOML2. CYB5A combined with STOML2 can predict the outcome of patients. To demonstrate the effect of CYB5A on JAK1 inhibitor function, we applied Ruxolitinib in metastatic tumors with high CYB5A expression and found that it slowed disease progression and prolonged survival in mice. To the best of our knowledge, this study is the first to report the Ruxolitinib effect on the metastatic ability of HCC cells in vivo and in vitro.


Assuntos
Proteínas Sanguíneas/metabolismo , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas de Membrana/metabolismo , Animais , Autofagia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Citocromos b5/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Metástase Neoplásica , Nitrilas , Pirazóis , Pirimidinas
11.
Cancer Res ; 81(23): 5889-5903, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34580062

RESUMO

As a member of the phospholipase family, phospholipase C beta 1 (PLCB1) is involved in phospholipid hydrolysis and is frequently upregulated in human cancer. However, little is known about the role of PLCB1 in cholangiocarcinoma (CCA). In this study, we uncover a role for PLCB1 in CCA progression and identify the underlying mechanisms. Both human CCA tissues and CCA cell lines expressed high levels of PLCB1. PLCB1 promoted tumor development and growth in various CCA mouse models, including transposon-based tumorigenesis models. PLCB1 activated PI3K/AKT signaling to induce CCA cells to undergo epithelial-to-mesenchymal transition (EMT). Mechanistically, PABPC1 interacted with PLCB1 and PI3K to amplify PLCB1-mediated EMT via PI3K/AKT/GSK3ß/Snail signaling. Ectopic PLCB1 induced resistance to treatment with gemcitabine combined with cisplatin, which could be reversed by the AKT inhibitor MK2206. PLCB1 expression was regulated by miR-26b-5p through direct interaction with PLCB1 3'UTR. Collectively, these data identify a PLCB1-PI3K-AKT signaling axis vital for CCA development and EMT, suggesting that AKT can be used as a therapeutic target to overcome chemotherapy resistance in CCA patients with high PLCB1 expression. SIGNIFICANCE: PLCB1 functions as an oncogenic driver in cholangiocarcinoma development that confers an actionable therapeutic vulnerability to AKT inhibition.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Fosfatidilinositol 3-Quinases/metabolismo , Fosfolipase C beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese , Movimento Celular , Proliferação de Células , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/genética , Fosfolipase C beta/genética , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
12.
Front Pharmacol ; 11: 589114, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33679385

RESUMO

GLP-1 analogs have been widely used to treat patients with type 2 diabetes in recent years and studies have found that GLP-1 analogs have multiple organ benefits. However, the role of GLP-1 analogs in diabetic retinopathy (DR), a common complication of diabetes mellitus (DM), remains controversial. Retinal ganglion cells (RGCs) are the only afferent neurons responsible for transmitting visual information to the visual center and are vulnerable in the early stage of DR. Protection of RGC is vital for visual function. The incretin glucagon-like peptide-1 (GLP-1), which is secreted by L-cells after food ingestion, could lower blood glucose level through stimulating the release of insulin. In the present study, we evaluated the effects of GLP-1 analog on RGCs both in vitro and in vivo. We established diabetic rat models in vivo and applied an RGC-5 cell line in vitro. The results showed that in high glucose conditions, GLP-1 analog alleviated the damage of RGCs. In addition, GLP-1 analog prevented mitophagy through the PINK1/Parkin pathway. Here we demonstrated the neuroprotective effect of GLP-1 analog, which may be beneficial for retinal function, and we further elucidated a novel mechanism in GLP-1 analog-regulated protection of the retina. These findings may expand the multi-organ benefits of GLP-1 analogs and provide new insights for the prevention of DR.

13.
Eur J Pharmacol ; 864: 172715, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31593687

RESUMO

Non-alcoholic steatohepatitis (NASH) is a key step in the progression of non-alcoholic fatty liver disease (NAFLD), which causes serious health problems worldwide. The nucleotide-binding oligomerization domain, leucine-rich repeat-containing receptor-containing pyrin domain 3 (NLRP3) inflammasome and pyroptosis play crucial roles in the progression of NASH. Our team has provided clinical evidence of the effects of glucagon-like peptide-1 (GLP-1) on the improvement in liver function and histological resolution of NAFLD. Preliminary work has demonstrated that GLP-1 inhibited NLRP3 inflammasome activation in a mouse model of NAFLD. We further explored the potential molecular mechanisms underlying the anti-inflammatory effect of liraglutide, a long-acting GLP-1 analog, in the treatment of NASH. We established a HepG2 cell model of NASH using double stimulation with palmitic acid and lipopolysaccharide to assess NLRP3 inflammasome and pyroptotic cell activity and to evaluate mitochondrial function and mitophagy. Liraglutide reduced lipid accumulation, inhibited NLRP3 inflammasome and pyroptosis activation, attenuated mitochondrial dysfunction and reactive oxygen species generation, augmented mitophagy in hepatocytes. Mitophagy inhibition with 3-methyladenine/PINK1-directed siRNA weakened the liraglutide-mediated suppression of inflammatory injury. We propose that liraglutide suppresses NLRP3 inflammasome-induced hepatocyte pyroptosis via mitophagy to slow the progression of NASH.


Assuntos
Inflamassomos/metabolismo , Liraglutida/farmacologia , Mitofagia/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Piroptose/efeitos dos fármacos , Progressão da Doença , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Liraglutida/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Espécies Reativas de Oxigênio/metabolismo
14.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): o1611, 2008 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-21203304

RESUMO

The mol-ecule of the title compound, C(18)H(17)N(7)S, is non-planar, with a dihedral angle of 71.4 (4)° between the two triazole rings, and an angle of 15.5 (3)° between the two phenyl rings. An intra-molecular N-H⋯S hydrogen bond forms a five-membered ring.

15.
Peptides ; 100: 123-126, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28807775

RESUMO

For a long time, diabetic retinopathy (DR) has been one of the most severe complications of diabetes. The early treatment of DR is not clearly recognized. The additional benefit of hypoglycemic agents for DR has become a new research field. Glucagon-like peptide-1 receptor (GLP-1R) has been shown to be widely expressed in tissues including retina. Glucagon-like peptide-1 receptor agonists (GLP-1RA) have been generally used in the treatment of diabetic patients. Studies shows that GLP-1RA could inhibit nerve damage by decrease apoptosis of nerve cells and activation of glial cells. In addition, GLP-1RA plays a protective role for tight junction (TJ) and cells of blood retinal barrier (BRB). It also protects retina from BRB damage. In this review, we discuss the potential protective mechanisms of GLP-1RA for DR beyond the hypoglycemic effects.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/uso terapêutico , Degeneração Neural/tratamento farmacológico , Apoptose/efeitos dos fármacos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Retina/efeitos dos fármacos , Retina/patologia
16.
Peptides ; 105: 7-13, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29746877

RESUMO

Retinal pericyte migration represents a novel mechanism of pericyte loss in diabetic retinopathy (DR), which plays a crucial role in the early impairment of the blood-retinal barrier (BRB). Glucagon-like peptide-1 (GLP-1) has been shown to protect the diabetic retina in the early stage of DR; however, the relationship between GLP-1 and retinal pericytes has not been discussed. In this study, advanced glycation end products (AGEs) significantly increased the migration of primary bovine retinal pericytes without influencing cell viability. AGEs also significantly enhanced phosphatidylinositol 3-kinase (PI3K)/Akt activation, and changed the expressions of migration-related proteins, including phosphorylated focal adhesion kinase (p-FAK), matrix metalloproteinase (MMP)-2 and vinculin. PI3K inhibition significantly attenuated the AGEs-induced migration of retinal pericytes and reversed the overexpression of MMP-2. Glucagon-like peptide-1 receptor (Glp1r) was expressed in retinal pericytes, and liraglutide, a GLP-1 analog, significantly attenuated the migration of pericytes by Glp1r and reversed the changes in p-Akt/Akt, p-FAK/FAK, vinculin and MMP-2 levels induced by AGEs, indicating that the protective effect of liraglutide was associated with the PI3K/Akt pathway. These results provided new insights into the mechanism underlying retinal pericyte migration. The early use of liraglutide exerts a potential bebefical effect on regulating pericyte migration, which might contribute to mechanisms that maintain the integrity of vascular barrier and delay the development of DR.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Produtos Finais de Glicação Avançada/metabolismo , Pericitos/metabolismo , Retina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Barreira Hematorretiniana/metabolismo , Bovinos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Quinase 1 de Adesão Focal/metabolismo , Peptídeo 1 Semelhante ao Glucagon/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Liraglutida/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Pericitos/efeitos dos fármacos , Retina/patologia
17.
Biosens Bioelectron ; 26(5): 2737-41, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21035321

RESUMO

Physical light source is absolutely necessary for usual photoelectrochemical measurement. In this work, chemiluminescence reaction rather than physical light source was used for the development of a novel photoelectrochemical DNA biosensor. CIPO (bis(2,4,5-trichlro-6-n-pentoxycarbonylphenyl)oxalate)-H(2)O(2)-9,10-diphenylanthrancene was selected as a CL system, which can produce appropriate exciting light and excite photoelectro active materials Ru(bpy)(2)dppz(2+) intercalated into the double-stranded DNA. Using such simple intercalation method, a detection limit of 4.5×10(-9) M target DNA was achieved without any amplification process. In addition, the selected CL system could be used to excite AuNPs-Ru(bpy)(2)dppz(2+) complex as well as CdSe QD multilayer, which indicated a good applicability for the established method.


Assuntos
Técnicas Biossensoriais/instrumentação , Condutometria/instrumentação , DNA/análise , DNA/genética , Iluminação/instrumentação , Medições Luminescentes/instrumentação , Fotometria/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
18.
Chem Commun (Camb) ; (37): 5624-6, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19753378

RESUMO

A chemiluminescence (CL) probe of peroxidase-like dicopper complex (Cu2L2) for the determination of glutathione (GSH) and related cellular thiols was developed for the first time.


Assuntos
Cobre/química , Medições Luminescentes/métodos , Compostos Organometálicos/química , Compostos de Sulfidrila/análise , Animais , Leucemia P388 , Luminol/química , Camundongos , Proteínas/química , Células Tumorais Cultivadas
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