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1.
Toxicol Lett ; 334: 94-101, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33010382

RESUMO

Silica dust mainly attacks alveolar macrophages (AMs). The apoptosis of AMs is correlated with the progress of silicosis. Our previous study showed that autophagic degradation was blocked in AMs from silicosis patients. However, the effects of nicotine on AM autophagy and apoptosis in silicosis are unknown. In this study, we collected AMs from twenty male workers exposed to silica and divided them into observer and silicosis patient groups, according to the tuberous pathological changes observed by X-ray. The AMs from both groups were exposed to nicotine. We found increased levels of LC3, p62, and cleaved caspase-3, decreased levels of LAMP2, and damaged lysosomes after nicotine stimulation of the AMs from both groups. We also found that the autophagy inhibitor 3-methyladenine (3MA) inhibited nicotine-induced apoptosis in the AMs. Furthermore, 3MA reversed both the nicotine-induced decrease in Bcl-2 and the increase in Bax in both groups. These results suggest that nicotine may induce apoptosis by blocking AM autophagic degradation in human silicosis.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Macrófagos Alveolares/efeitos dos fármacos , Nicotina/toxicidade , Silicose/patologia , Adenina/análogos & derivados , Adenina/farmacologia , Caspase 3/metabolismo , Células Cultivadas , Humanos , Marcação In Situ das Extremidades Cortadas , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Dióxido de Silício/toxicidade , Silicose/metabolismo
2.
Life Sci ; 259: 118187, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32781061

RESUMO

AIMS: Voluntary exercise training has cardioprotective effects in humans, but the underlying mechanism is unknown. This research was done to estimate the effect of voluntary exercise training to attenuate middle-aged maturity-induced cardiac apoptosis. MATERIALS AND METHODS: The study was designed to divide 64 male mice randomly into four groups, consisting of a 9-month sedentary pre-middle-aged group (9M), 15-month sedentary middle-aged group (15M), and two exercise groups using a voluntary wheel running respectively (9M+EX, 15M+EX). After 3 months, the condition of cardiac apoptosis in different groups was measured by HE dying, TUNEL and DAPI staining, and Western Blot analysis. KEY FINDINGS: TUNEL-positive cells were increased in 15M group compared with 9M group, while decreased in 9M+EX and 15M+EX groups compared with their control groups respectively. Protein levels of AIF, Endo G, TNF-α, TNFR1, TRAF2, TRADD, Fas, FasL, FADD, activated caspase 8, 3, 9, Bax/Bcl2, Bak/BclxL, and tBid were decreased in 9M+EX and 15M+EX groups compared with their control groups respectively. The protein levels of pBad/Bad, 14-3-3, IGF1, IGFR1, pPI3K/PI3K, and pAKT/AKT were more activated in the 9M+EX and 15M+EX groups than those in their control groups respectively. Significant differences were found between 9M group and 15M group for the protein levels of TRAF2, FADD, Bax/Bcl2, tBid and pAKT/AKT. SIGNIFICANCE: Voluntary exercise training as an important lifestyle modification may prevent cardiac widely dispersed apoptosis and enhance cardiac survival at middle-aged maturity.


Assuntos
Envelhecimento/fisiologia , Apoptose/fisiologia , Coração/fisiologia , Condicionamento Físico Animal/fisiologia , Animais , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/fisiologia , Corrida/fisiologia , Comportamento Sedentário
3.
Life Sci ; 261: 118314, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32835699

RESUMO

AIMS: Placental tissues from patients with preeclampsia (PE) and in the lipopolysaccharide (LPS)-induced PE-like model were used to investigate the implication of placental inflammation and apoptosis in PE. Whether the beneficial effects of nicotine are related to inhibition of placental inflammation and apoptosis in the PE-like model were investigated. MAIN METHODS: Placental apoptosis was detected in PE patients and the PE-like rat model by TUNEL staining. Changes in the number of CD68+ macrophages in placental tissues from PE patients were detected by immunofluorescent staining. The mRNA expression of the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin (IL-1ß), MCP-1, and proteins involved in extrinsic or intrinsic apoptosis signaling in the PE-like model was determined by qRT-PCR; immunofluorescent staining was used to detect the expression of TNF-α receptor (TNFR1), MCP-1 and apoptosis-related proteins. KEY FINDINGS: Placental apoptosis was increased in both PE patients and the PE-like model, more macrophages infiltrated into placenta in PE patients. A significant upregulation in mRNA expression of TNF-α, IL-1ß, MCP-1, and caspase 3, caspase 8, caspase 9 was found in the PE-like rats compared to the control animals, the immunoreactivity of placental MCP-1, TNFR1, and apoptosis-related proteins (caspase 3, caspase 8, caspase 9, Bax) was also enhanced; nicotine treatment significantly reversed those changes. SIGNIFICANCE: Our data suggests that the protective effects of nicotine are associated with inhibiting placenta inflammation and apoptosis, and nicotine might be a potentially therapeutic candidate for preventing preeclampsia.


Assuntos
Inflamação/tratamento farmacológico , Nicotina/farmacologia , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/prevenção & controle , Adulto , Animais , Apoptose/efeitos dos fármacos , Estudos de Casos e Controles , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Inflamação/patologia , Lipopolissacarídeos/toxicidade , Macrófagos/metabolismo , Placenta/patologia , Pré-Eclâmpsia/patologia , Gravidez , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Regulação para Cima , Adulto Jovem
4.
Life Sci ; 256: 118031, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615186

RESUMO

AIMS: We had previously reported that addition of putrescine to the culture medium was reported to reduce methylmercury toxicity in C17.2 neural stem cells. Here, we have examined the inhibition of methylmercury-induced cytotoxicity by putrescine using ODC1-overexpressing C17.2 cells. MATERIALS AND METHODS: We established stable ODC1-overexpressing C17.2 cells and evaluated methylmercury-induced apoptosis by examining the TUNEL assay and cleaved caspase-3 levels. Mitochondria-mediated apoptosis was also evaluated by reduction of mitochondrial membrane potential and recruitment of Bax and Bak to the mitochondria. KEY FINDINGS: ODC is encoded by ODC1 gene, and putrescine levels in ODC1-overexpressing cells were significantly higher than in control cells. Overexpression of ODC1 and addition of putrescine to the culture medium suppressed DNA fragmentation and caspase-3 activation, which are observed when apoptosis is induced by methylmercury. Moreover, mitochondrial dysfunction and reactive oxygen species (ROS) generation, caused by methylmercury, were also inhibited by the overexpression of ODC1 and putrescine; pretreatment with ODC inhibitor, however, promoted both ROS generation and apoptosis by methylmercury. Finally, we found that Bax and Bak, the apoptosis-promoting factors, to be increased in mitochondria, following methylmercury treatment, and the same was inhibited by overexpression of ODC1. These results suggest that overexpression of ODC1 may prevent mitochondria-mediated apoptosis by methylmercury via increase of putrescine levels. SIGNIFICANCE: Our findings provide important clues to clarify mechanisms involved in the defense against methylmercury toxicity and suggest novel biological functions of putrescine.


Assuntos
Compostos de Metilmercúrio/toxicidade , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Ornitina Descarboxilase/genética , Putrescina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Marcação In Situ das Extremidades Cortadas , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/patologia , Células-Tronco Neurais/patologia
5.
Bratisl Lek Listy ; 121(8): 580-583, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726121

RESUMO

OBJECTIVES: We investigated the effect of low, medium and high doses of oral vitamin A, on the number of fetal hippocampal neurons. BACKGROUND: High doses of vitamin A during pregnancy may cause embryonic malformations. There are reports about dosages that don't cause macroscopic malformations, but may cause mental and behavioral disorders. Still, quantitative morphological studies explaining this topic are lacking. METHODS: We administered oral vitamin A to pregnant rats on the 10th-12th days of pregnancy at doses of 10000, 20000, 30000, 40000, 50000, 100000 and 200000 IU/kg. We collected the fetuses on the 19th day and removed their brains. After staining with cresyl violet and immunolabeling with Tunel and Ki67 antibody, we examined the hippocampi with stereological methods. RESULTS: Vitamin A decreased hippocampal neuron numbers beginning from 20000 IU/kg. While the number of Ki67 positive cells increased with the dosage, the increase of apoptotic cells begun at the dose of 50000 IU/kg. CONCLUSION: Our study demonstrates that vitamin A, beginning from the dosage of 20000 IU/kg, is decreasing the total hippocampal neuron numbers during the critical period of embryonic brain development and that apoptosis may not be the only factor in this outcome (Tab. 1, Fig. 3, Ref. 27).


Assuntos
Hipocampo , Neurônios , Vitamina A , Vitaminas , Animais , Apoptose , Feminino , Hipocampo/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Neurônios/efeitos dos fármacos , Gravidez , Ratos , Vitamina A/farmacologia , Vitaminas/farmacologia
6.
Life Sci ; 260: 118098, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679145

RESUMO

AIMS: Spinal cord injury (SCI) is one of the most devastating diseases that challenges neurology and medicine, leading to paraplegia or quadriplegia worldwide. Neuroprotection conferred by histone deacetylase (HDAC) inhibitors against various insults and deficits in the central nervous system has been reported previously. Herein, we set out to ascertain whether HDAC3 inhibition exerts neuroprotective effects against SCI. MAIN METHODS: A modified Allen's weight-drop method was performed to induce experimental SCI in rats. Basso-Beattie-Bresnahan (BBB) scores were used to assess locomotor function. Flow cytometric analysis of AnnexinV-FITC/PI double staining, TUNEL staining, and immunoblotting analysis of apoptosis-related proteins were performed to determine apoptosis in H2O2-induced cell injury of primary rat neurons. KEY FINDINGS: Upregulated HDAC3 and downregulated miR-27a were observed in spinal cord tissues of SCI rats and H2O2-injured neurons. HDAC3 knockdown by its specific shRNA restored the locomotor function of SCI rats and prevented rat neurons from H2O2-induced apoptosis through promotion of miR-27a. miR-27a targeted PAK6 (encoding P21-activated kinase 6) and inhibited its expression. The effects of HDAC3 knockdown on the locomotor function of SCI rats and H2O2-induced apoptosis of rat neurons were lost upon further PAK6 overexpression. SIGNIFICANCE: The present study uncovers that silencing HDAC3 inhibited PAK6 expression by upregulating miR-27a, eventually inhibiting neuron apoptosis and promoting the recovery of SCI, which might provide a novel therapeutic target for SCI.


Assuntos
Inativação Gênica , Histona Desacetilases/genética , MicroRNAs/genética , Traumatismos da Medula Espinal/terapia , Quinases Ativadas por p21/genética , Animais , Apoptose/fisiologia , Modelos Animais de Doenças , Citometria de Fluxo , Expressão Gênica/fisiologia , Peróxido de Hidrogênio/farmacologia , Marcação In Situ das Extremidades Cortadas , Locomoção/fisiologia , Masculino , MicroRNAs/fisiologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Regulação para Cima , Quinases Ativadas por p21/antagonistas & inibidores
7.
Life Sci ; 254: 117772, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32437794

RESUMO

AIMS: This study aimed to explore that the human neural stem cell derived extracellular vesicles (hNSC-EVs) have therapeutic effect on neuronal hypoxia-reperfusion (H/R) injured neurons in vitro by mediating the nuclear translocation of NF-E2-related factor 2 (Nrf2) to regulate the expression of downstream oxidative kinases. MAIN METHODS: The neuroprotective effects of hNSC-EVs were evaluated in an in vitro neuronal H/R model. Three parameters of hNSC-EVs, structure, phenotype and particle size, were characterized. At the cellular level, a human neuron cerebral ischemic reperfusion (CIR) injury model was constructed. Cell viability, apoptosis, and the amount of reactive oxygen species (ROS) were detected using real-time cell analysis (RTCA), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and dichloro-dihydro-fluorescein diacetate (DCFH-DA), respectively. The neuronal axonal elongation was assessed by Opera Phenix™ screening system. The angiogenesis of human umbilical vein endothelial cells (HUVECs) was evaluated by co-culturing HUVECs with hNSC-EVs in Matrigel. The expression of apoptosis and oxidative stress-related proteins in cells and the nuclear transfer of Nrf2 following hypoxia-reperfusion (H/R) was verified by Western-blotting. KEY FINDINGS: We found that the hNSC-EVs can promote the survival of post-H/R injury neurons, inhibit neuronal apoptosis, and enhance nuclear transfer of Nrf2, in response to oxidative stress. We also found the hNSC-EVs can promote the elongation of neuronal axons and the angiogenesis of HUVECs. SIGNIFICANCE: At present, there is no effective therapy for CIR injury. We suggest that the hNSC-EVs could be considered a new strategy to achieve nerve repair for the treatment of neurological diseases, especially stroke.


Assuntos
Vesículas Extracelulares/metabolismo , Células-Tronco Neurais/metabolismo , Traumatismo por Reperfusão/terapia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Vesículas Extracelulares/fisiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hipóxia/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Marcação In Situ das Extremidades Cortadas/métodos , Células-Tronco Mesenquimais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Células-Tronco Neurais/fisiologia , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
8.
Invest Ophthalmol Vis Sci ; 61(5): 31, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32428232

RESUMO

Purpose: More recently, literature has emerged providing findings about the novelty of microRNAs (miR)-targeted therapeutics in the treatment of retinoblastoma (RB). The prime objective of this study was to identify the potential role of miR-378a-3p and its regulation in RB cells via forkhead box G1 (FOXG1). Methods: The expression of miR-378a-3p and FOXG1 in the clinical RB tissues was determined using RNA quantitation and Western blot assays. The interaction between miR-378a-3p and FOXG1 was identified using dual luciferase reporter gene assay. The potential effects of miR-378a-3p on the RB cell biological processes were evaluated by conducting gain- and loss-of-function studies of miR-378a-3p and FOXG1, followed by cell viability, cell cycle progression, and apoptosis measurements. Furthermore, experiments were performed in nude mice to assess its effects on tumor formation. Results: miR-378a-3p was poorly expressed, whereas FOXG1 was highly expressed in RB tissues and cells. miR-378a-3p bound to the FOXG1 3' untranslated region and negatively modulated its expression. The overexpression of miR-378a-3p was found to decrease RB cell viability and to promote cell apoptosis in vitro, whereas overexpressed FOXG1 reversed the regulatory effects of miR-378a-3p on RB cellular behaviors. In nude mice, the restoration of miR-378a-3p by miR-378a-3p agomir was shown to play a role in the reduction of tumor volume and size relative to nude mice injected with negative control-agomir. Conclusions: Our findings identified that increased miR-378a-3p exerted an inhibitory effect on RB cell proliferation by targeting FOXG1, suggesting the role of miR-378a-3p as a novel therapeutic target for RB.


Assuntos
Apoptose , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , MicroRNAs/fisiologia , Proteínas do Tecido Nervoso/genética , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Animais , Western Blotting , Ciclo Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Pré-Escolar , Feminino , Citometria de Fluxo , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Humanos , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas do Tecido Nervoso/metabolismo , Plasmídeos/genética , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias da Retina/metabolismo , Retinoblastoma/metabolismo , Organismos Livres de Patógenos Específicos , Transfecção , Transplante Heterólogo , Células Tumorais Cultivadas
9.
Nat Commun ; 11(1): 2303, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385276

RESUMO

White adipose tissue (WAT) expansion in obesity occurs through enlargement of preexisting adipocytes (hypertrophy) and through formation of new adipocytes (adipogenesis). Adipogenesis results in WAT hyperplasia, smaller adipocytes and a metabolically more favourable form of obesity. How obesogenic WAT hyperplasia is induced remains, however, poorly understood. Here, we show that the mechanosensitive cationic channel Piezo1 mediates diet-induced adipogenesis. Mice lacking Piezo1 in mature adipocytes demonstrated defective differentiation of preadipocyte into mature adipocytes when fed a high fat diet (HFD) resulting in larger adipocytes, increased WAT inflammation and reduced insulin sensitivity. Opening of Piezo1 in mature adipocytes causes the release of the adipogenic fibroblast growth factor 1 (FGF1), which induces adipocyte precursor differentiation through activation of the FGF-receptor-1. These data identify a central feed-back mechanism by which mature adipocytes control adipogenesis during the development of obesity and suggest Piezo1-mediated adipocyte mechano-signalling as a mechanism to modulate obesity and its metabolic consequences.


Assuntos
Adipócitos/metabolismo , Fator 1 de Crescimento de Fibroblastos/metabolismo , Canais Iônicos/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Adipogenia/fisiologia , Tecido Adiposo Branco/metabolismo , Animais , Calorimetria , Células Cultivadas , Feminino , Fator 1 de Crescimento de Fibroblastos/genética , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Insulina/sangue , Interleucina-6/sangue , Canais Iônicos/genética , Masculino , Camundongos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
10.
Life Sci ; 256: 117811, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32422306

RESUMO

Acute myocardial infarction (AMI) is a major cardiovascular disease with high mortality worldwide. Hypoxia is a key inducing factor for AMI. We aimed to examine the expression and functions of Kcnq1ot1 (KCNQ1 overlapping transcript 1) in hypoxia-induced cardiomyocytes in the process of AMI. The left anterior descending coronary artery ligation (LAD) was used for inducing in-vivo AMI model and the primary cardiomyocytes were extracted; in-vitro H9c2 cell model was simulated by hypoxia treatment. TUNEL, flow cytometry and JC-1 assay were carried out to evaluate cell apoptosis. Mechanism assays including luciferase reporter assay and RIP assay revealed interplays between RNAs. To begin with, Kcnq1ot1 was revealed to be conspicuously upregulated in myocardium infracted zone and border zone within 2 days since establishment of the model. Moreover, inhibition of Kcnq1ot1 protected cardiomyocytes against hypoxia-triggered cell apoptosis during the process of AMI. Then, miR-466k and miR-466i-5p were proved to bind with Kcnq1ot1 and participated in Kcnq1ot1-mediated cardiomyocyte injury under hypoxia. Subsequently, Kcnq1ot1 was found to elevate Tead1 (TEA domain transcription factor 1) expression via sponging miR-466k and miR-466i-5p. Finally, it was verified that Kcnq1ot1 regulated hypoxia-induced cardiomyocyte injury dependent on Tead1. In conclusion, Kcnq1ot1 sponged miR-466k and miR-466i-5p to up-regulate Tead1, thus triggering cardiomyocyte injury in the process of AMI.


Assuntos
Apoptose/genética , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , RNA Longo não Codificante/genética , Animais , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas , Masculino , MicroRNAs/genética , Infarto do Miocárdio/genética , Proteínas Nucleares/genética , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/genética , Regulação para Cima
11.
Invest Ophthalmol Vis Sci ; 61(4): 5, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32271885

RESUMO

Purpose: Neurons carry electrical signals and communicate via electrical activities. The therapeutic potential of electrical stimulation (ES) for the nervous system, including the retina, through improvement of cell survival and function has been noted. Here we investigated the neuroprotective and regenerative potential of ES in a mouse model of inherited retinal degeneration. Methods: Rhodopsin-deficient (Rho-/-) mice received one or two sessions of transpalpebral ES or sham treatments for 7 consecutive days. Intraperitoneal injection of 5-ethynyl-2'-deoxyuridine was used to label proliferating cells. Weekly electroretinograms were performed to monitor retinal function. Retinal morphology, photoreceptor survival, and regeneration were evaluated in vivo using immunohistochemistry and genetic fate-mapping techniques. Müller cell (MC) cultures were employed to further define the optimal conditions of ES application. Results: Noninvasive transpalpebral ES in Rho-/- mice improved photoreceptor survival and electroretinography function in vivo. ES also triggered residential retinal progenitor-like cells such as MCs to reenter the cell cycle, possibly producing new photoreceptors, as shown by immunohistochemistry and genetic fate-mapping techniques. ES directly stimulated cell proliferation and the expression of progenitor cell markers in MC cultures, at least partially through bFGF signaling. Conclusions: Our study showed that transpalpebral ES improved photoreceptor survival and retinal function and induced the proliferation, probably photoreceptor regeneration, of MCs; this occurs via stimulation of the bFGF pathways. These results suggest the exciting possibility of applying noninvasive ES as a versatile tool for preventing photoreceptor loss and mobilizing endogenous progenitors for reversing vision loss in patients with photoreceptor degeneration.


Assuntos
Modelos Animais de Doenças , Terapia por Estimulação Elétrica , Células Fotorreceptoras de Vertebrados/citologia , Degeneração Retiniana/terapia , Células Ganglionares da Retina/fisiologia , Animais , Ciclo Celular/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Eletrorretinografia , Células Ependimogliais , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Knockout , Degeneração Retiniana/genética , Degeneração Retiniana/fisiopatologia , Rodopsina/genética
12.
Invest Ophthalmol Vis Sci ; 61(4): 15, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32298438

RESUMO

Purpose: Pathological neovascularization and fibrosis are common pathological changes of many retinal diseases, such as proliferative retinopathy (PR) and age-related macular degeneration (AMD). Treatment modalities for these pathological changes are limited. The purpose of the present study was to test the effects of palmitoylethanolamide (PEA), an endocannabinoid mimetic amide, on retinal neovascularization and fibrosis and to determine its molecular mechanism of action. Methods: A rat Müller cell line (rMC-1), a mouse model of oxygen-induced retinopathy (OIR), and the very-low-density lipoprotein receptor (VLDLR) knockout mouse model were used. PEA was intraperitoneally injected or orally administrated in animal models. Inflammation and profibrotic changes were evaluated by western blot analysis. Glial fibrillary acidic protein (GFAP) and peroxisome proliferator-activated receptor alpha (PPARα) were measured by RT-PCR and western blot analysis. Results: Profibrotic changes were present in OIR and Vldlr-/- retinas. PEA significantly alleviated inflammation and inhibited neovascularization in OIR and Vldlr-/- retinas and suppressed profibrotic changes in OIR and Vldlr-/- retinas. Moreover, PEA potently suppressed Müller gliosis in these retinas. In rMC-1 cells, PEA suppressed Müller gliosis, reduced inflammatory cytokines, and attenuated profibrotic changes. Further, both mRNA and protein levels of PPARα were elevated in the retina under PEA treatment, and the effects of PEA were abolished in Pparα-/- OIR mice. Conclusions: PEA reduced retinal neovascularization and fibrotic changes and suppressed Müller gliosis in experimental PR and neovascular AMD by activating PPARα. PEA may be a potential treatment for retinopathies with pathological neovascularization and fibrosis.


Assuntos
Agonistas de Receptores de Canabinoides/uso terapêutico , Etanolaminas/uso terapêutico , Gliose/tratamento farmacológico , PPAR alfa/metabolismo , Ácidos Palmíticos/uso terapêutico , Retina/patologia , Neovascularização Retiniana/tratamento farmacológico , Administração Oral , Animais , Western Blotting , Linhagem Celular , Modelos Animais de Doenças , Células Ependimogliais/efeitos dos fármacos , Fibrose/tratamento farmacológico , Fibrose/metabolismo , Fibrose/patologia , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/metabolismo , Gliose/patologia , Marcação In Situ das Extremidades Cortadas , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxigênio/toxicidade , PPAR alfa/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Receptores de LDL/genética , Retina/metabolismo , Neovascularização Retiniana/induzido quimicamente , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia
14.
Environ Toxicol ; 35(6): 714-721, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32149473

RESUMO

Spinal cord injury (SCI) is the most commonly seen trauma leading to disability in people worldwide. The purpose of current study was to determine the protective effect of methoxytetrahydro-2H-pyran-2-yl)methyl benzoate (HMPB) on SCI in rat model. TUNEL staining was used to examine apoptotic changes in spinal cord of SCI rats. The ELISA kits were employed to assess inflammatory processes and oxidative factors in the spinal cord tissues. Behavioral changes in SCI rats were assessed using Basso, Beattie, and Bresnahan (BBB) scoring system. Western blotting was used for assessment of proteins. The HMPB treatment of SCI rats reduced apoptotic cell number based on the concentration of dose administered. Treatment of SCI rats with HMPB enhanced BBB score and decreased accumulation of water content in SCI rats significantly. On treatment with HMPB the TNF-α and interleukin-6/1ß/18 levels were suppressed in SCI rats. Treatment with HMPB induced excessive release of SOD, CAT, and GSH molecules and decreased overproduction of MDA. The SCI induced upregulation of caspase-3/9 activity was completely alleviated by HMPB at 2 mg/kg dose. The HMPB treatment of SCI rats promoted peroxisome proliferator-activated receptor γ (PPAR-γ) expression, reduced cyclooxygenase (COX)-2 production and increased expression of p-Akt and phosphoinositide 3-kinase (p-PI3K). The study demonstrated that HMPB suppressed apoptosis, raised BBB score and inhibited inflammation in SCI rats. Moreover, activation of PI3K/Akt in the spinal cord tissues of SCI rats was promoted by HMPB. Therefore, HMPB has protective effect on SCI in the rat model.


Assuntos
PPAR gama/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piranos/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Crataegus , Citocinas/metabolismo , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas , Inflamação , Masculino , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Piranos/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
15.
Exp Eye Res ; 193: 107997, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32165157

RESUMO

We aimed to assess the neuroprotective effect of a pyruvate dehydrogenase kinase (PDK) inhibitor, Nov3r after ischemia/reperfusion (IR) injury in rats. IR injury was induced by applying 150 mmHg of intraocular pressure for 50 min. Nov3r was orally administered (100 mg/kg) 3 h before and 24 h after IR injury. TUNEL-positive cells increased and immunoreactive RBPMS-positive cells decreased in the rat retinas after IR injury. Administration of Nov3r significantly ameliorated the increase in TUNEL-positive cells and prevented the RBPMS-positive cell decrease. Similarly, the number of IR-induced Iba1-positive microglial cells was significantly reduced with Nov3r treatment. Among metabolic parameters, IR damage induced the elevation of lactate and pyruvate, and the reduction of ATP. Oral administration of Nov3r ameliorated these changes. Our data suggest that the Nov3r had a retinal neuroprotective effect in IR injury in rats. This finding suggests that the regulation of pyruvate dehydrogenase (PDH) activity has potential therapeutic value by enabling metabolic reprograming in diseases associated with ischemic retinal damage, such as diabetic retinopathy, retinopathy of prematurity, retinal vein occlusion, ischemic optic neuropathy and glaucoma.


Assuntos
Metabolismo Energético/fisiologia , Quinase Piruvato Desidrogenase (Transferência de Acetil)/antagonistas & inibidores , Traumatismo por Reperfusão/prevenção & controle , Doenças Retinianas/prevenção & controle , Células Ganglionares da Retina/patologia , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Células Ganglionares da Retina/efeitos dos fármacos
16.
Exp Eye Res ; 193: 107964, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32044305

RESUMO

Methamphetamine (METH), an addictive stimulant of neurotransmitters, is associated with cardiovascular and neurological diseases. METH-induced ophthalmic complications are also present but have been insufficiently investigated. The purpose of this study is to investigate the retinal effects of METH. C57BL/6 mice were administrated progressively increasing doses of METH (0-6 mg/kg) by repetitive intraperitoneal injections for 5 days (4 times per day). Retinal degeneration was examined by morphological changes and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling (TUNEL) assay. Norepinephrine levels were measured by ELISA, protein expression levels were determined by immunoblot and immunostaining, and gelatinase activity was examined by zymography. The thickness of the retina and the number of nuclei in the inner and outer nuclear layers were decreased by METH. Retinal cell death and astrocyte activation by METH treatment were confirmed by TUNEL assay and glial fibrillary acidic protein expression, respectively. Increased tumor necrosis factor-α protein in the retina and elevated norepinephrine levels in plasma were found in METH-treated mice. Platelet endothelial cell adhesion molecule-1 (PECAM-1) protein expression level was decreased in the retina and central retinal artery (CRA) by METH treatment, along with the endothelial proteoglycans glypican-1 and syndecan-1. Moreover, a regulator of the extracellular matrix, matrix metalloproteinase-14 (MMP-14) in the retina, and MMP-2 and MMP-9 in plasma, were increased by METH treatment. In conclusion, METH administration is involved in retinal degeneration with a vascular loss of PECAM-1 and the glycocalyx in the CRA and retina, and an increase of MMPs.


Assuntos
Metanfetamina/farmacocinética , Retina/patologia , Artéria Retiniana/patologia , Degeneração Retiniana/patologia , Animais , Estimulantes do Sistema Nervoso Central/efeitos adversos , Estimulantes do Sistema Nervoso Central/farmacocinética , Modelos Animais de Doenças , Eletrorretinografia , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Marcação In Situ das Extremidades Cortadas , Masculino , Metanfetamina/efeitos adversos , Camundongos , Camundongos Endogâmicos C57BL , Retina/efeitos dos fármacos , Artéria Retiniana/efeitos dos fármacos , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/metabolismo
17.
Exp Eye Res ; 193: 107957, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32032627

RESUMO

Vision loss is a devastating consequence of systemic hypoxia, but the cellular mechanisms are unclear. We investigated the impact of acute hypoxia in the retina and optic nerve. We induced systemic hypoxia (10% O2) in 6-8w mice for 48 h and performed in vivo imaging using optical coherence tomography (OCT) at baseline and after 48 h to analyze structural changes in the retina and optic nerve. We analyzed glial cellular and molecular changes by histology and immunofluorescence and the impact of pretreatment with 4-phenylbutyric acid (4-PBA) in oligodendroglia survival. After 48 h hypoxia, we found no change in ganglion cell complex thickness and no loss of retinal ganglion cells. Despite this, there was significantly increased expression of CCAAT-enhancer-binding protein homologous protein (CHOP), a marker of endoplasmic reticulum stress, in the retina and optic nerve. In addition, hypoxia induced obvious increase of GFAP expression in the anterior optic nerve, where it co-localized with CHOP, and significant loss of Olig2+ oligodendrocytes. Pretreatment with 4-PBA, which has been shown to reduce endoplasmic reticulum stress, rescued total Olig2+ oligodendrocytes and increased the pool of mature (CC-1+) but not of immature (PDGFRa+) oligodendrocytes. Consistent with a selective vulnerability of the retina and optic nerve in hypoxia, the most striking changes in the 48 h murine model of hypoxia were in glial cells in the optic nerve, including increased CHOP expression in the astrocytes and loss of oligodendrocytes. Our data support a model where glial dysfunction is among the earliest events in systemic hypoxia - suggesting that glia may be a novel target in treatment of hypoxia.


Assuntos
Hipóxia/complicações , Neuroglia/patologia , Doenças do Nervo Óptico/diagnóstico , Nervo Óptico/patologia , Animais , Sobrevivência Celular , Modelos Animais de Doenças , Feminino , Hipóxia/diagnóstico , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos C57BL , Doenças do Nervo Óptico/etiologia , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos
18.
Invest Ophthalmol Vis Sci ; 61(1): 3, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31995154

RESUMO

Purpose: The purpose of this study was to investigate the expression of death ligands in the lacrimal glands (LGs), identify upstream factors that regulate their expression, and determine the functional roles of these factors in the pathogenesis of dry eye disease (DED). Methods: For DED experiment, ex vivo coculture system with LG and in vivo murine model using a controlled environment chamber were utilized. C57BL/6 mice and hypoxia-inducible factor (HIF)-1α conditional knockout (CKO) mice were used. Immunohistochemical staining, polymerase chain reaction, and immunoblotting were performed to determine levels of death ligands including tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in DED-induced LGs. Additionally, acinar cell and CD45+ cell apoptosis was determined with neutralizing TRAIL treatment. Results: Desiccating stress significantly increased HIF-1α expression in LG-acinar cells. Furthermore, HIF-1α deficiency significantly enhanced the infiltration of CD45+ inflammatory cells in LG and induced LG-acinar cell death. Meanwhile, only TRAIL expression was increased in DED-LG, but abrogated in HIF-1α CKO. Interestingly, the main source of TRAIL was the CD45- LG-acinar cells, but not CD45+ immune cells after DED induction. Using ex vivo coculture system, we confirmed LG-induced apoptosis of immune cells via HIF-1α-mediated TRAIL secretion following DED. Consistent with ex vivo, the insufficiency of HIF-1α and TRAIL enhanced recruitment of inflammatory cells to the LG and subsequently exacerbated ocular surface damage in DED mice. Conclusions: Our findings offer novel insight into the regulatory function of acinar cell-derived TRAIL in limiting inflammatory damage and could be implicated in the development of potential therapeutic strategies for DED.


Assuntos
Dacriocistite/metabolismo , Síndromes do Olho Seco/metabolismo , Regulação da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Aparelho Lacrimal/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética , Animais , Apoptose , Técnicas de Cocultura , Dacriocistite/patologia , Modelos Animais de Doenças , Síndromes do Olho Seco/patologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Immunoblotting , Marcação In Situ das Extremidades Cortadas , Aparelho Lacrimal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Reação em Cadeia da Polimerase em Tempo Real
19.
Life Sci ; 245: 117347, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31981628

RESUMO

AIM: Oxidative stress plays an important role in myocardial ischemia-reperfusion injury. Pleckstrin homology-like domain, family A, member 1 (PHLDA1) was first identified in apoptosis induced by T cell receptor activation, and was shown to play a different role in different cell types and under different stimuli. The role and mechanism of PHLDA1 in oxidative stress-induced cardiomyocyte injury and cardiac ischemia-reperfusion were therefore determined. MAIN METHODS: Cell viability and apoptotic rate were measured by Cell Counting Kit-8 and flow cytometry, respectively. Mitochondrial membrane potential was measured using JC-1 test kit. Reactive oxygen species (ROS) production was detected using ROS kit. HE staining was used to detect histological morphology, 2,3,5-triphenyltetrazolium chloride staining to detect infarct size, terminal deoxynucleotidyl transferase dUTP nick end labeling staining to detect the apoptotic rate, and immunohistochemistry and western blot analysis to detect protein expression. The binding of PHLDA1 to Bcl-2 associated X (Bax) was detected by immunoprecipitation. KEY FINDINGS: The results indicated that PHLDA1 is highly expressed in oxidative stress-induced cardiomyocyte and myocardial ischemia-reperfusion injuries. PHLDA1 overexpression in cardiomyocytes promoted oxidative stress-induced cardiomyocyte injury. At the same time, PHLDA1 knockdown improved oxidative stress-induced cardiomyocyte and myocardial ischemia-reperfusion injuries. In addition, PHLDA1 binds to Bax and the interaction is enhanced under H2O2 stimulation. SIGNIFICANCE: The present results indicated that PHLDA1 interacts with Bax to participate in oxidative stress-induced cardiomyocyte injury and myocardial ischemia reperfusion injury.


Assuntos
Proteínas Reguladoras de Apoptose/fisiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Estresse Oxidativo , Animais , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Western Blotting , Linhagem Celular , Citometria de Fluxo , Imunoprecipitação , Marcação In Situ das Extremidades Cortadas , Masculino , Potencial da Membrana Mitocondrial , Miócitos Cardíacos/fisiologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
20.
Life Sci ; 245: 117351, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31981629

RESUMO

AIMS: To study the specific therapeutic effect of zinc on spinal cord injury (SCI) and its specific protective mechanism. MAIN METHODS: The effects of zinc ions on neuronal cells were examined in a mouse SCI model and in vitro. In vivo, neurological function was assessed by Basso Mouse Scaleat (BMS) at 1, 3, 5, 7, 10, 14, 21, and 28 days after spinal cord injury. The number of neurons and histomorphology were observed by nissl staining and hematoxylin-eosin staining (HE). The chromatin and mitochondrial structure of neurons were detected by transmission electron microscopy (TEM). The expression of nuclear factor erythroid 2 related factor 2 (Nrf2)-related antioxidant protein and NLRP3 inflammation-related protein were detected in vivo and in vitro by western blot (WB) and immunofluorescence (IF), respectively. KEY FINDINGS: Zinc treatment promoted motor function recovery on days 3, 5, 7, 14, 21 and 28 after SCI. In addition, zinc reduces the mitochondrial void rate in spinal neuronal cells and promotes neuronal recovery. At the same time, zinc reduced the levels of reactive oxygen species (ROS) and malondialdehyde in spinal cord tissue after SCI, while increasing superoxide dismutase activity and glutathione peroxidase production. Zinc treatment resulted in up-regulation of Nrf2/Ho-1 levels and down-regulation of nlrp3 inflammation-associated protein expression in vitro and in vivo. SIGNIFICANCE: Zinc has a protective effect on spinal cord injury by inhibiting oxidative damage and nlrp3 inflammation. Potential mechanisms may include activation of the Nrf 2/Ho-1 pathway to inhibit nlrp3 inflammation following spinal cord injury. Zinc has the potential to treat SCI.


Assuntos
Heme Oxigenase-1/metabolismo , Proteínas de Membrana/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Zinco/uso terapêutico , Animais , Western Blotting , Modelos Animais de Doenças , Feminino , Imunofluorescência , Marcação In Situ das Extremidades Cortadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Transmissão , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Medula Espinal/citologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Zinco/farmacologia
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