Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.576
Filtrar
1.
Cell Prolif ; 53(2): e12759, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922310

RESUMO

OBJECTIVE: Low levels of adiponectin (APN), a biomarker of diabetes mellitus, have been implicated in the poor outcome of intracerebral haemorrhage (ICH). Herein, we aimed to demonstrate the neuroprotective effects of a blood-brain barrier-permeable APN peptide (APNp) on ICH injury in diabetic mice and explore the underlying mechanisms. MATERIALS AND METHODS: Recombinant APNp was administrated intraperitoneally to mice with collagenase-induced ICH. Neurological deficits, brain water content and neural apoptosis were assessed. Western blotting, immunofluorescence staining, quantitative RT-PCR and transmission electron microscopy were used to determine the signalling pathways affected by APNp. RESULTS: Adiponectin peptide significantly alleviated neural apoptosis, neurological deficits and brain oedema following ICH in diabetic mice. Mechanistically, APNp promoted the restoration of peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α related mitochondrial function and suppressed activating transcription factor 4 (ATF4)-CCAAT-enhancer-binding protein homologous protein (CHOP)-induced neural apoptosis. Furthermore, Smad3 signalling was found to play a regulatory role in this process by transcriptionally regulating the expression of PGC-1α and ATF4. APNp significantly suppressed the elevated phosphorylation and nuclear translocation of Smad3 after ICH in diabetic mice, while the protective effects of APNp on mitochondrial and ATF4-CHOP apoptosis pathways were counteracted when Smad3 was activated by exogenous transforming growth factor (TGF)-ß1 treatment. CONCLUSIONS: Our study provided the first evidence that APNp promoted neural survival following ICH injury in the diabetic setting and revealed a novel mechanism by which APNp suppressed mitochondrial and ATF4-CHOP apoptosis pathways in a Smad3 dependent manner.


Assuntos
Adiponectina/metabolismo , Apoptose/fisiologia , Hemorragia Cerebral/metabolismo , Diabetes Mellitus Experimental/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Transdução de Sinais/fisiologia , Fator 4 Ativador da Transcrição/metabolismo , Animais , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transporte Proteico/fisiologia , Proteínas Recombinantes/metabolismo , Proteína Smad3/metabolismo , Fator de Transcrição CHOP/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
2.
DNA Cell Biol ; 39(2): 210-225, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31809190

RESUMO

Myocardial ischemic disease affects the prognosis in perioperative patients. Diabetes can aggravate myocardial injury. The purpose of this research is to investigate the effect of ferroptosis in the process of diabetes mellitus (DM) myocardial ischemia/reperfusion (I/R) injury (IRI). Endoplasmic reticulum stress (ERS) is investigated whether aggravates cardiomyocytes injury. Rat DM+I/R (DIR), cell high glucose (HG), hypoxia reoxygenation (H/R), and high-glucose H/R (HH/R) models were established. Ferroptosis inhibitor Ferrostatin-1, ferroptosis agonist Erastin, ERS inhibitor Salubrinal, and ERS agonist Tunicamycin were administered. Serum creatine kinase-MB (CK-MB), cell viability, lactate dehydrogenase (LDH), malondialdehyde (MDA), superoxide dismutase (SOD), reactive oxygen species (ROS), and cellular ferrous ion concentration were examined. The level of ACSL4, GPX4, ATF4, CHOP, BCL-2, and BAX was detected. Myocardial tissue pathological change was detected by hematoxylin-eosin staining. Cardiac function was monitored by invasive hemodynamic measurements. Evans Blue-triphenyltetrazolium chloride double staining was used to detect the myocardial infarct size. In DM+sham (DS) (or HG) and I/R (or H/R) models, cardiomyocytes were injured accompanied by increased level of ferroptosis and ERS. Moreover, the cell injury was more serious in rat DIR or cell HH/R models. Inhibition of ferroptosis in DIR model could reduce ERS and myocardial injury. Inhibition of ferroptosis in H9c2 cells HG, H/R, and HH/R models could reduce cell injury. Erastin could aggravate ERS and cell injury by stimulating ferroptosis in HH/R cell model. Meanwhile, inhibition of ERS could alleviate ferroptosis and cell injury. Ferroptosis is involved in DIR injury that is related to ERS. Moreover, inhibition of ferroptosis can alleviate DIR injury, which may provide a therapeutic regent for myocardial ischemic disease.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Coenzima A Ligases/metabolismo , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/fisiologia , Masculino , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição CHOP/metabolismo
3.
Cell Prolif ; 53(1): e12706, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642559

RESUMO

OBJECTIVE: Withaferin A (WA) is a bioactive compound with a remarkable anti-cancer effect derived from Withania somnifera, commonly known as ashwagandha. However, the anti-cancer mechanisms of WA in glioblastoma multiforme (GBM) are still unclear. MATERIALS AND METHODS: Cell viability assays and xenografted nude mice were used to evaluate the effects of WA, along with flow cytometry to detect apoptosis and cell cycle of GBM. RNA-seq analysis, Western blotting, immunofluorescence staining, qRT-PCR and siRNA gene silencing were carried out to determine the signalling pathways affected by WA. RESULTS: Withaferin A significantly inhibited the growth of GBM in vitro and in vivo and triggered the intrinsic apoptosis of GBM cells by up-regulating expression of Bim and Bad. WA arrested GBM cells at the G2/M phase of the cell cycle through dephosphorylating Thr161 of CDK1 by activating p53-independent p21 up-regulation. Knockdown of p21 restored cell cycle progression and cell viability by down-regulating the expression of Bad rather than Bim. We demonstrated that endoplasmic reticulum (ER) stress induced by WA through the ATF4-ATF3-CHOP axis, initiated apoptosis and G2/M arrest in GBM cells. CONCLUSION: We revealed a novel pathway that elucidated WA activation of apoptosis and G2/M arrest in GBM cells through the ATF4-ATF3-CHOP axis. This discovery is important for optimization of WA-based regimens for prevention and/or treatment of GBM.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo , Vitanolídeos/farmacologia , Animais , Linhagem Celular Tumoral , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Photochem Photobiol B ; 202: 111720, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31841988

RESUMO

It has been widely reported that ultraviolet-B (UV-B) radiation is the main extrinsic etiological agent that causes skin photodamage. UV-B exposure mediated photodamage (photo-aging/photo-carcinogenesis) to human skin is caused due to several physiological events at tissue, cellular and molecular levels that lead to impairment of skin function and integrity. In the present study, we investigated the protective role of Trigonelline (TG) against UV-B induced photo-damage in Human Dermal Fibroblasts (Hs68 cells) and Balb/C mice. We exposed human skin fibroblasts and Balb/C mice to UV-B radiation and evaluated various parameters of cellular damage, including, oxidative stress, cytosolic calcium (Ca2+) levels, apoptotic and ER-stress marker proteins. We found that UV-B irradiation induced ROS generation lead to the depletion of endoplasmic reticulum (ER) calcium and increased the expression of ER stress protein markers (phosphorylated elf2α, CHOP, ATF4) as well as apoptotic protein markers (Bcl2, Bax and caspase-9) in a dose and time dependent manner in Hs68 cells. We then determined the effect of TG treatment on UV-B -induced cell death in Hs68 cells and observed that cells exposed to UV-B radiation and treated with TG had a significantly higher survival rate compared to cells exposed to UV-B radiation alone. TG treatment successfully reduced oxidative stress; restored Ca2+ homeostasis and re-established the ER function and prevented apoptotic cell death process. Our results suggest that TG can be used as a potential therapeutic/cosmeceutic agent in preventing skin photo-damage.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Raios Ultravioleta , Animais , Apoptose/efeitos da radiação , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos da radiação , Fator de Iniciação 1 em Eucariotos/genética , Fator de Iniciação 1 em Eucariotos/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/efeitos da radiação , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
5.
World J Gastroenterol ; 25(38): 5800-5813, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31636473

RESUMO

BACKGROUND: Sirtuin 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase that is involved in various diseases, including cancers, metabolic diseases, and inflammation-associated diseases. However, the role of SIRT1 in ulcerative colitis (UC) is still confusing. AIM: To investigate the role of SIRT1 in intestinal epithelial cells (IECs) in UC and further explore the underlying mechanisms. METHODS: We developed a coculture model using macrophages and Caco-2 cells. After treatment with the SIRT1 activator SRT1720 or inhibitor nicotinamide (NAM), the expression of occludin and zona occludens 1 (ZO-1) was assessed by Western blot analysis. Annexin V-APC/7-AAD assays were performed to evaluate Caco-2 apoptosis. Dextran sodium sulfate (DSS)-induced colitis mice were exposed to SRT1720 or NAM for 7 d. Transferase-mediated dUTP nick-end labeling (TUNEL) assays were conducted to assess apoptosis in colon tissues. The expression levels of glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, caspase-9, and caspase-3 in Caco-2 cells and the colon tissues of treated mice were examined by quantitative real-time PCR and Western blot. RESULTS: SRT1720 treatment increased the protein levels of occludin and ZO-1 and inhibited Caco-2 apoptosis, whereas NAM administration caused the opposite effects. DSS-induced colitis mice treated with SRT1720 had a lower disease activity index (P < 0.01), histological score (P < 0.001), inflammatory cytokine levels (P < 0.01), and apoptotic cell rate (P < 0.01), while exposure to NAM caused the opposite effects. Moreover, SIRT1 activation reduced the expression levels of GRP78, CHOP, cleaved caspase-12, cleaved caspase-9, and cleaved caspase-3 in Caco-2 cells and the colon tissues of treated mice. CONCLUSION: SIRT1 activation reduces apoptosis of IECs via the suppression of endoplasmic reticulum stress-mediated apoptosis-associated molecules CHOP and caspase-12. SIRT1 activation may be a potential therapeutic strategy for UC.


Assuntos
Apoptose , Colite Ulcerativa/patologia , Estresse do Retículo Endoplasmático , Mucosa Intestinal/patologia , Sirtuína 1/metabolismo , Animais , Células CACO-2 , Caspase 12/metabolismo , Técnicas de Cocultura , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Humanos , Mucosa Intestinal/citologia , Macrófagos , Camundongos , Niacinamida/administração & dosagem , Sirtuína 1/antagonistas & inibidores , Fator de Transcrição CHOP/metabolismo
6.
Braz J Med Biol Res ; 52(11): e8772, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31664306

RESUMO

This study aimed to investigate the mechanism of fluorofenidone (AKF-PD) in treating renal interstitial fibrosis in rats with unilateral urinary obstruction (UUO). Thirty-two male Sprague-Dawley rats were randomly divided into sham, UUO, UUO + enalapril, and UUO + AKF-PD groups. All rats, except sham, underwent left urethral obstruction surgery to establish the animal model. Rats were sacrificed 14 days after surgery, and serum was collected for renal function examination. Kidneys were collected to observe pathological changes. Immunohistochemistry was performed to assess collagen I (Col I) protein expression, and terminal deoxynucleotidyl transferase-mediated nick end-labeling staining to observe the apoptosis of renal tubular epithelial cells. The expression of Fas-associated death domain (FADD), apoptotic protease activating factor-1 (Apaf-1), and C/EBP homologous protein (CHOP) proteins was evaluated by immunohistochemistry and western blot analysis. AKF-PD showed no significant effect on renal function in UUO rats. The pathological changes were alleviated significantly after enalapril or AKF-PD treatment, but with no significant differences between the two groups. Col I protein was overexpressed in the UUO group, which was inhibited by both enalapril and AKF-PD. The number of apoptotic renal tubular epithelial cells was much higher in the UUO group, and AKF-PD significantly inhibited epithelial cells apoptosis. The expression of FADD, Apaf-1, and CHOP proteins was significantly upregulated in the UUO group and downregulated by enalapril and AKF-PD. In conclusion, AKF-PD improved renal interstitial fibrosis by inhibiting apoptosis of renal tubular epithelial cells in rats with UUO.


Assuntos
Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Nefropatias/patologia , Piridonas/farmacologia , Obstrução Ureteral/patologia , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Fator Apoptótico 1 Ativador de Proteases/efeitos dos fármacos , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Nitrogênio da Ureia Sanguínea , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Creatinina/sangue , Modelos Animais de Doenças , Enalapril/metabolismo , Enalapril/farmacologia , Proteína de Domínio de Morte Associada a Fas/efeitos dos fármacos , Proteína de Domínio de Morte Associada a Fas/metabolismo , Fibrose , Masculino , Piridonas/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Fator de Transcrição CHOP/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo
7.
Mol Med Rep ; 20(3): 2832-2842, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31524237

RESUMO

Bupivacaine has previously been reported to induce neurotoxicity, which is further enhanced by high glucose levels. In the present study, the underlying molecular mechanisms via which bupivacaine induces cytotoxicity under high glucose conditions were investigated in cultured human SH­SY5Y cells. In order to identify the optimal concentrations of glucose and bupivacaine that induced cytotoxicity, SH­SY5Y cells were treated with 30­100 mM glucose and 0.5­1.0 mM bupivacaine. Based on the dose response experiments, 50 mM glucose and 0.5 mM bupivacaine was used in the present study. The effects that 3­MA (autophagy inhibitor) and rapamycin (RAPA; autophagy inducer) exerted on cell apoptosis, autophagy and the expression of protein kinase R­like endoplasmic reticulum kinase (PERK)­activating transcription factor 4 (ATF4)­C/EBP­homologous protein (CHOP) and inositol­requiring enzyme 1 (IRE1)­tumor necrosis factor receptor associated factor 2 (TRAF2) signaling proteins were measured in high glucose and bupivacaine­treated cells. Cell viability was measured using a Cell Counting Kit­8 assay, cell apoptosis was assessed using flow cytometry, and protein expression was determined using western blot analyses. Compared with the control group, high glucose and bupivacaine significantly increased ATF4, CHOP and caspase­12 expression, increased apoptosis, and decreased p­IRE1, TRAF2, LC3­II/LC3­I and Beclin1 expression. Promoting autophagy with RAPA partly reversed the high glucose and bupivacaine­induced changes in p­PERK, CHOP, TRAF2, Beclin1, caspase­12 and apoptosis, while inhibiting autophagy with 3­MA further enhanced the changes in ATF4, CHOP, p­IRE1, TRAF2 and apoptosis. High glucose and bupivacaine induced cytotoxicity in SH­SY5Y cells, at least in part, through enhancing cell apoptosis and inhibiting autophagy via the PERK­ATF4­CHOP and IRE1­TRAF2 signaling pathways.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Bupivacaína/farmacologia , Glucose/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator 4 Ativador da Transcrição/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Endorribonucleases/metabolismo , Humanos , Modelos Biológicos , Proteínas Serina-Treonina Quinases/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo
8.
Int J Mol Sci ; 20(18)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491992

RESUMO

Hepatocyte death is critical for the pathogenesis of liver disease progression, which is closely associated with endoplasmic reticulum (ER) stress responses. However, the molecular basis for ER stress-mediated hepatocyte injury remains largely unknown. This study investigated the effect of ER stress on dual-specificity phosphatase 5 (DUSP5) expression and its role in hepatocyte death. Analysis of Gene Expression Omnibus (GEO) database showed that hepatic DUSP5 levels increased in the patients with liver fibrosis, which was verified in mouse models of liver diseases with ER stress. DUSP5 expression was elevated in both fibrotic and acutely injured liver of mice treated with liver toxicants. Treatment of ER stress inducers enhanced DUSP5 expression in hepatocytes, which was validated in vivo condition. The induction of DUSP5 by ER stress was blocked by either treatment with a chemical inhibitor of the protein kinase RNA-like endoplasmic reticulum kinase (PERK) pathway, or knockdown of C/EBP homologous protein (CHOP), whereas it was not affected by the silencing of IRE1 or ATF6. In addition, DUSP5 overexpression decreased extracellular-signal-regulated kinase (ERK) phosphorylation, but increased cleaved caspase-3 levels. Moreover, the reduction of cell viability under ER stress condition was attenuated by DUSP5 knockdown. In conclusion, DUSP5 expression is elevated in hepatocytes by ER stress through the PERK-CHOP pathway, contributing to hepatocyte death possibly through ERK inhibition.


Assuntos
Fosfatases de Especificidade Dupla/genética , Estresse do Retículo Endoplasmático , Hepatócitos/metabolismo , Transdução de Sinais , Fator de Transcrição CHOP/metabolismo , eIF-2 Quinase/metabolismo , Animais , Apoptose/genética , Morte Celular/genética , Expressão Gênica , Hepatócitos/patologia , Humanos , Hepatopatias/etiologia , Hepatopatias/metabolismo , Camundongos
9.
Life Sci ; 235: 116858, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31505195

RESUMO

AIMS: The current study was conducted to investigate the potential protective effects of hesperidin and its possible mechanisms of action on pancreatic ß-cells in diabetes. MAIN METHODS: Male Sprague Dawley rats were made diabetic using 65 mg/kg intraperitoneal injection of streptozotocin, and then administered daily with 100 mg/kg of hesperidin over 4 weeks. On conclusion of the experiment, blood and pancreatic tissue were collected to determine the function of ß-cells, apoptosis, oxidative stress, ER stress, and inflammation. KEY FINDINGS: Treatment of diabetic rats with hesperidin, significantly decreased fasting blood glucose and food intake, along with increased body weight, serum and pancreatic insulin levels, and pancreatic-duodenal homeobox-1 (PDX-1) protein expression. The beneficial roles of hesperidin on diabetic pancreatic ß-cells exhibited an increment in antioxidant SOD and GPx activities, and a decrement in nitrotyrosine as well as malondialdehyde (MDA) levels. Additionally, the elevated concentration of TNF-α and expressions of ER stress maker GRP78 and CHOP proteins in the pancreas of diabetic rats were significantly diminished by hesperidin treatment. Furthermore, hesperidin effectively modulated expressions of apoptosis-regulatory proteins in diabetic rat pancreas, as revealed by upregulating anti-apoptotic Bcl-xL; with a concomitant downregulating pro-apoptotic Bax, cleaved caspase-3, and inhibiting the activation of DNA repair protein poly (ADP-ribose) polymerase (PARP). SIGNIFICANCE: Collectively, these findings suggest that hesperidin may have the potential to protect pancreatic ß-cells and improve their function by suppressing oxidative and ER stress, along with activating its antioxidant, anti-inflammatory, and anti-apoptotic effects.


Assuntos
Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/prevenção & controle , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Hesperidina/farmacologia , Células Secretoras de Insulina/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Glicemia/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Homeodomínio/biossíntese , Inflamação , Insulina/sangue , Insulina/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/metabolismo , Substâncias Protetoras/farmacologia , Ratos , Superóxido Dismutase/metabolismo , Transativadores/biossíntese , Fator de Transcrição CHOP/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
10.
Sheng Li Xue Bao ; 71(4): 527-536, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31440749

RESUMO

The aim of this study was to investigate whether G protein-coupled estrogen receptor (GPER) could alleviate hippocampal neuron injury under cerebral ischemia-reperfusion injury (CIRI) by acting on endoplasmic reticulum stress (ERS). The CIRI animal model was established by middle cerebral artery occlusion (MCAO). Female ovariectomized (OVX) Sprague-Dawley (SD) female rats were randomly divided into 4 groups: control, ischemia-reperfusion injury (MCAO), vehicle (MCAO+DMSO), and GPER-specific agonist G1 (MCAO+G1) groups. The neurobehavioral score was assessed by the Longa score method, the morphological changes of the neurons were observed by the Nissl staining, the cerebral infarction was detected by the TTC staining, and the neural apoptosis in the hippocampal CA1 region was detected by TUNEL staining. The distribution and expression of GRP78 (78 kDa glucose-regulated protein 78) in the hippocampal CA1 region were observed by immunofluorescent staining. The protein expression levels of GRP78, Caspase-12, CHOP and Caspase-3 were detected by Western blot, and the mRNA expression levels of GRP78, Caspase-12, and CHOP were detected by the real-time PCR. The results showed that the neurobehavioral score, cerebral infarct volume, cellular apoptosis index, as well as GRP78, Caspase-12 and CHOP protein and mRNA expression levels in the MCAO group were significantly higher than those of control group. And G1 reversed the above-mentioned changes in the MCAO+G1 group. These results suggest that the activation of GPER can decrease the apoptosis of hippocampal neurons and relieve CIRI, and its mechanism may involve the inhibition of ERS.


Assuntos
Isquemia Encefálica , Estresse do Retículo Endoplasmático , Neurônios/citologia , Receptores Estrogênicos/fisiologia , Receptores Acoplados a Proteínas-G/agonistas , Traumatismo por Reperfusão , Animais , Apoptose , Região CA1 Hipocampal/citologia , Caspase 12/metabolismo , Caspase 3/metabolismo , Feminino , Proteínas de Choque Térmico/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Transcrição CHOP/metabolismo
11.
Cancer Sci ; 110(10): 3275-3287, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31368616

RESUMO

p97/VCP is an endoplasmic reticulum (ER)-associated protein that belongs to the AAA (ATPases associated with diverse cellular activities) ATPase family. It has a variety of cellular functions including ER-associated protein degradation, autophagy, and aggresome formation. Recent studies have shown emerging roles of p97/VCP and its potential as a therapeutic target in several cancer subtypes including multiple myeloma (MM). We conducted a cell-based compound screen to exploit novel small compounds that have cytotoxic activity in myeloma cells. Among approximately 2000 compounds, OSSL_325096 showed relatively strong antiproliferative activity in MM cell lines (IC50 , 100-500 nmol/L). OSSL_325096 induced apoptosis in myeloma cell lines, including a bortezomib-resistant cell line and primary myeloma cells purified from patients. Accumulation of poly-ubiquitinated proteins, PERK, CHOP, and IREα, was observed in MM cell lines treated with OSSL_325096, suggesting that it induces ER stress in MM cells. OSSL_325096 has a similar chemical structure to DBeQ, a known p97/VCP inhibitor. Knockdown of the gene encoding p97/VCP induced apoptosis in myeloma cells, accompanied by accumulation of poly-ubiquitinated protein. IC50 of OSSL_325096 to myeloma cell lines were found to be lower (0.1-0.8 µmol/L) than those of DBeQ (2-5 µmol/L). In silico protein-drug-binding simulation suggested possible binding of OSSL_325096 to the ATP binding site in the D2 domain of p97/VCP. In cell-free ATPase assays, OSSL_325096 showed dose-dependent inhibition of p97/VCP ATPase activity. Finally, OSSL_325096 inhibited the growth of subcutaneous myeloma cell tumors in vivo. The present data suggest that OSSL_325096 exerts anti-myeloma activity, at least in part through p97/VCP inhibition.


Assuntos
Adenosina Trifosfatases/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Proteínas Nucleares/metabolismo , Bibliotecas de Moléculas Pequenas/administração & dosagem , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/química , Animais , Sítios de Ligação , Bortezomib/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Camundongos , Modelos Moleculares , Mieloma Múltiplo/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/química , Proteínas Serina-Treonina Quinases/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Fator de Transcrição CHOP/metabolismo , Ubiquitinação , Ensaios Antitumorais Modelo de Xenoenxerto , eIF-2 Quinase/metabolismo
12.
Environ Toxicol ; 34(12): 1340-1353, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31433112

RESUMO

This study investigated whether the apoptotic effect induced by cadmium chloride (CdCl2 ) in rat's hippocampi and neuroprotection afforded by resveratrol (RES) are mediated by modulation of ER stress and involve sirtuin 1 (SIRT1)/AMPK/Akt axis. Adult male Wistar rats were divided into four groups (n = 24/group) as control, control + RES (300 mg/kg), CdCl2 (5 mg/kg), and CdCl2 + RES. All treatments were conducted orally for 45 days. Also, cultured hippocampal cells were treated with CdCl2 in the presence or absence of RES and with or without preincubation with SIRT1, AMPK, or PI3K inhibitors. CdCl2 impaired retention and spatial memories of rats and reduced levels and activities of SIRT1 and inhibited AMPK/Akt axis in their hippocamapi where SIRT1 was the upstream regulator. It also enahnced hippocampal levels of reactive oxygen species (ROS) and expression of caspase-12 and caspase-3, depleted glutathione (GSH) levels, and activated GRP78, activating transcription factor-6, GAAD 153, X-box binding protein-1 arms of ER stress. On the contrary, RES coadminsitration completley abolished all these events. Interstingly and in control rats, RES not only increased levels of GSH, but also enhenced protein levels of B-cell lymphoma 2 (Bcl-2) and dwonregulated GAAD 153. In both control and CdCl2 -treated rats, pharmacological inhibtion of SIRT1, AMPK, and Akt compleltely abolished all effects afforded by RES. In conclusion, CdCl2 -induced hippocampal apopotis is associated with reduction of SIRT1/AMPK/Akt activity levels, ROS generation, downregulation of Bcl-2, and activities, activation of ER stress, and GAAD 153, whereas RES is able to reverse these effects through activation of SIRT1/AMPK/Akt.


Assuntos
Cloreto de Cádmio/toxicidade , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Resveratrol/farmacologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fator de Transcrição CHOP/metabolismo , Regulação para Cima/efeitos dos fármacos
13.
Life Sci ; 232: 116612, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260687

RESUMO

AIMS: Accumulating evidence suggest that endoplasmic reticulum (ER) stress is an important mechanism underlying the development of diabetes. We have reported that sustained treatment with N-methyl-d-aspartate (NMDA) results in apoptotic ß-cell death and impairs insulin secretion. However, the molecular mechanism responsible for NMDA-induced ß-cell dysfunction remains largely obscure. Thus, this study aimed to determine whether sustained activation of NMDA receptors (NMDARs) causes ß-cell dysfunction through ER stress. MAIN METHODS: Primary mouse islets and MIN6 mouse pancreatic ß-cells were treated with NMDA for 24 h or high-glucose for 72 h. After the treatment, glucose-stimulated insulin secretion (GSIS) and the expression of ER stress markers were measured, respectively. In vivo, the expression of ER stress markers was measured in the pancreas of diabetic mice treated with or without NMDARs inhibitor Memantine. KEY FINDINGS: NMDA treatment caused an increase in the expression of ER stress markers (ATF4, CHOP, GRP78, and Xbp1s) in primary islets. While, tauroursodeoxycholic acid (TUDCA), an inhibitor of ER stress, significantly attenuated NMDA-induced ß-cell dysfunction, including the loss of glucose-stimulated insulin secretion and reduction of pancreas duodenum homeobox factor-1 (Pdx-1) mRNA expression, a transcription factor regulating insulin synthesis. Besides, NMDA-induced ER stress strongly promoted pro-inflammatory cytokines synthesis (IL-1ß and TNF-α) in ß cells. Interestingly, knockdown of CHOP attenuated ß-cell dysfunction evoked by NMDA. Furthermore, we demonstrated that blockade of NMDARs ameliorated high-glucose-induced ER stress in vitro and in vivo. SIGNIFICANCE: This study confirms that ER stress is actively involved in the activation of NMDARs-related ß-cell dysfunction.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Células Secretoras de Insulina/metabolismo , Fator de Transcrição CHOP/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glucose/metabolismo , Proteínas de Choque Térmico/metabolismo , Insulina/metabolismo , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , N-Metilaspartato/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais , Proteína 1 de Ligação a X-Box/metabolismo
14.
J Ethnopharmacol ; 243: 112093, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31325602

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ginseng (Panax ginseng C. A. Mey) has been widely used in Asian countries for thousands of years. It has auxiliary anticancer efficacy and its derived preparations (e.g. Shenmai injection) are prescribed for cancer patients as Traditional Chinese Medicines clinically in China. AIM OF THE STUDY: The involved adjuvant anticancer mechanisms of ginseng are still unknown. The present study evaluated the anti-cancer effect of total ginsenosides extract (TGS) and determined the anticancer mechanisms of TGS-induced cell death in human non-small cell lung cancer (NSCLC) cells. MATERIALS AND METHODS: The anti-cancer effect of TGS was evaluated in NSCLC by cell proliferation assay. The autophagy flux induction of TGS were tested and validated by Western blot, immunofluorescence and transmission electron microscope. The mechanisms of TGS in inducing autophagic cell death were validated by Western blot, gene knockdown and quantitative real time PCR assay. RESULTS: We found TGS could induce cell death in concentration and time dependent manners, and the cell morphology of NSCLC changed from cobblestone shape to elongated spindle shape after treated with TGS. In the study of cell autophagy, we confirm that TGS could upregulate autophagy flux and induce autophagic cell death through activation endoplasmic reticulum stress. Further investigations demonstrated this process was mediated by the ATF4-CHOP-AKT1-mTOR axis in NSCLC cells. CONCLUSION: Our findings suggested that TGS could induce autophagic cell death in NSCLC cells through activation of endoplasmic reticulum stress, disclosing another characteristic of TGS-induced cell death and a novel mechanism of TGS and its derived preparations in clinical treatment of cancer patients.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ginsenosídeos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Fator 4 Ativador da Transcrição/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Transcrição CHOP/metabolismo
15.
J Biosci ; 44(2)2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31180066

RESUMO

Ischemia-reperfusion (IR) is one of the significant medical problems in China. Triphenyltetrazolium chloride (TTC) staining is used to detect the status of the infarct size, and real-time PCR and western blotting are used to detect expressions of genes. TUNEL assay has been used to detect apoptosis. Using a tree shrew myocardial IR model, we found that in the reperfusion period, resina draconis (RD) treatment reduced the infarct size by TTC staining, and significantly enhanced the superoxide dismutase expression and down-regulated the malondialdehyde concentration in a dose-dependent manner. In hearts showing IR, Bax was increased and Bcl-2 was reduced, and RD treatment inhibited the IR-induced Bax expression and up-regulated the IR suppressed level of Bcl-2. TUNEL assay showed that IR induced the apoptosis of myocardial cells, and RD treatment suppressed the IR-induced apoptosis. CHOP and GRP78 were also upregulated in IR hearts, and RD treatment could significantly attenuate the CHOP and GRP78 levels compared with IR group. We further found that IR decreased the miR-423-3p expression and upregulated its target gene ERK both in mRNA and protein levels, and RD treatment upregulated miR-423-3p expression and downregulated ERK expression compared with the IR group. Importantly, miR-423-3p mimics inhibited IR increased ERK, CHOP and GRP78 expressions, and enhanced IR decreased Bcl-2 expression, and inhibited the IR-induced apoptosis of myocardial cells. The findings of this study suggest that RD treatment inhibited the endoplasmic reticulum induced apoptosis of myocardial cells via regulating miR-423-3p/ERK signaling pathway in a tree shrew myocardial IR model.


Assuntos
Cardiotônicos/farmacologia , Dracaena/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Resinas Vegetais/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Cardiotônicos/isolamento & purificação , Modelos Animais de Doenças , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Masculino , Malondialdeído/antagonistas & inibidores , Malondialdeído/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Resinas Vegetais/isolamento & purificação , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Tupaiidae , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Proteína de Morte Celular Associada a bcl/genética , Proteína de Morte Celular Associada a bcl/metabolismo
16.
Zhonghua Gan Zang Bing Za Zhi ; 27(4): 244-249, 2019 Apr 20.
Artigo em Chinês | MEDLINE | ID: mdl-31082333

RESUMO

Objective: To investigate the endoplasmic reticulum stress (ERS) role in the course of liver failure induced by severe hepatitis B virus (HBV) infection and its related mechanism. Methods: Liver tissue samples and clinical data [chronic hepatitis B patients (12 cases, chronic hepatitis B group), hepatic failure induced by severe hepatitis B virus (12 cases, severe hepatitis B virus liver failure group), and normal subjects (8 cases, control group)] were collected from the Beijing You'an Hospital affiliated to Capital Medical University between 2009 to 2011. Statistical analysis was performed on the clinical indicators of each group. The structure of endoplasmic reticulum in liver tissue was observed by transmission electron microscopy. Western blot and qRT-PCR were used to detect the expression of endoplasmic reticulum stress and apoptosis-related factors, including glucose-regulated protein (Grp), and C/EBP homologous protein (CHOP). Frozen sections of liver tissues were prepared for immunofluorescence test. All data were expressed as mean ± standard deviation. LSD-t test was used to compare the results between groups. A p value < 0.05 was considered as statistically significant. Results: Transmission electron microscopy showed that the morphological structure of the endoplasmic reticulum was damaged in both groups (chronic hepatitis B and liver failure induced by severe hepatitis B virus), and liver failure induced by severe hepatitis B virus group was more critical. Western blot and qRT-PCR showed that Grp78, Grp94 and Caspase-4 were highly expressed in normal group and chronic hepatitis B group, and the relative protein expressions were 1.20 ± 0.13 and 0.78 ± 0.11, 0.90 ± 0.06 and 0.11 ± 0.01, 0.15 ± 0.02 and 0.22 ± 0.04, respectively. The expression of protein was weakened in liver failure induced by severe hepatitis B virus group (relative protein expression was 0.01 ± 0, 0.01 ± 0, and 0.11 ± 0.02, respectively).There was a statistically significant difference between the two groups (P < 0.05). The expression of CHOP was consistent with the results of immunofluorescence, and increased with the stressing of injury. Conclusion: During the course of severe hepatitis B infection, dysregulated endoplasmic reticulum stress activated mild stress in chronic hepatitis B group, while severe stress in hepatic failure induced by severe hepatitis B virus group. Therefore, endoplasmic reticulum stress plays an important and complex role in the pathogenesis of hepatic failure induced by severe hepatitis B virus.


Assuntos
Estresse do Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Vírus da Hepatite B , Hepatite B , Falência Hepática/complicações , Fígado/patologia , Apoptose , Retículo Endoplasmático/virologia , Humanos , Fígado/virologia , Fator de Transcrição CHOP/metabolismo
17.
Phytomedicine ; 62: 152950, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31102888

RESUMO

BACKGROUND: The ability of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to preferentially induce apoptosis in transformed cells while sparing most normal cells is well established. However, the intrinsic and acquired resistance of tumors to TRAIL-induced apoptosis limits its therapeutic applicability. PURPOSE: We investigated the effect of caudatin, a species of C-21 steroidal glycosides isolated from the roots of Cynanchum auriculatum, on TRAIL-induced apoptosis in human breast cancer cells. METHODS: Cell growth inhibition was evaluated by the CCK-8 assay. The cell cycle distribution was assessed by propidium iodide flow cytometry. Apoptosis was determined by TUNEL staining. Protein expression was detected by western blotting analysis. RESULTS: Caudatin enhanced TRAIL-induced apoptosis in human breast cancer cells. This sensitization was achieved by upregulating death receptor 5 (DR5). Knockdown of DR5 abolished the enhancing effect of caudatin on TRAIL responses. The caudatin-induced upregulation of DR5 was accompanied by increased expression of CHOP and phosphorylation of p38 MAPK and JNK. CHOP knockdown blocked caudatin-upregulated DR5 expression. Moreover, cotreatment of breast cancer cells with p38 MAPK and JNK inhibitors significantly counteracted the caudatin-induced expression of DR5. CONCLUSION: Our results showed that caudatin sensitized breast cancer cells to TRAIL-induced apoptosis through activation of CHOP, p38 MAPK and JNK-mediated upregulation of DR5 expression. The combination of TRAIL and caudatin may be a promising therapeutic approach for the treatment of breast cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Glicosídeos/farmacologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Esteroides/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Mar Drugs ; 17(5)2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086026

RESUMO

Flaccidoxide-13-acetate, an active compound isolated from cultured-type soft coral Sinularia gibberosa, has been shown to have inhibitory effects against invasion and cell migration of RT4 and T24 human bladder cancer cells. In our study, we used an 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), colony formation assay, and flow cytometry to determine the mechanisms of the anti-tumor effect of flaccidoxide-13-acetate. The MTT and colony formation assays showed that the cytotoxic effect of flaccidoxide-13-acetate on T24 and RT4 cells was dose-dependent, and the number of colonies formed in the culture was reduced with increasing flaccidoxide-13-acetate concentration. Flow cytometry analysis revealed that flaccidoxide-13-acetate induced late apoptotic events in both cell lines. Additionally, we found that flaccidoxide-13-acetate treatment upregulated the expressions of cleaved caspase 3, cleaved caspase 9, Bax, and Bad, and down-regulated the expressions of Bcl-2, p-Bad, Bcl-x1, and Mcl-1. The results indicated that apoptotic events were mediated by mitochondrial dysfunction via the caspase-dependent pathway. Flaccidoxide-13-acetate also provoked endoplasmic reticulum (ER) stress and led to activation of the PERK-eIF2α-ATF6-CHOP pathway. Moreover, we examined the PI3K/AKT signal pathway, and found that the expressions of phosphorylated PI3K (p-PI3K) and AKT (p-AKT) were decreased with flaccidoxide-13-acetate concentrations. On the other hand, our results showed that the phosphorylated JNK and p38 were obviously activated. The results support the idea that flaccidoxide-13-acetate-induced apoptosis is mediated by mitochondrial dysfunction, ER stress, and activation of both the p38 and JNK pathways, and also relies on inhibition of PI3K/AKT signaling. These findings imply that flaccidoxide-13-acetate has potential in the development of chemotherapeutic agents for human bladder cancer.


Assuntos
Apoptose/efeitos dos fármacos , Diterpenos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico , Coelhos , Fator de Transcrição CHOP/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
19.
Mol Med Rep ; 19(6): 5169-5176, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059107

RESUMO

The aim of the present study was to probe the mechanism of apoptosis induced by endoplasmic reticulum stress (ERS) in manganese­induced rats. A total of 60 Sprague­Dawley rats were randomly divided into a Vehicle group, LoMag group, HiMag group, and HiMag + 4­phenylbutyrate (PBA) group. Manganese content was measured by Inductively Coupled Plasma­Atomic Emission Spectrometry. Pathogenic morphology, the cellular structure of the striatum and ER were observed by hematoxylin and eosin staining and electron microscopy. The TUNEL method was used to examine neuronal apoptosis in the rat striatum. The expression levels of glucose­regulated protein 78KD (GRP78), C/EBP homologous protein (CHOP), c­Jun N­terminal kinase (JNK) and caspase­12 were analyzed by western blot analysis. The results revealed that striatal manganese concentrations in the LoMag and HiMag groups were higher than that in the Vehicle group (P<0.01). Rat striatal neuronal structure and apoptotic rates in the LoMag and HiMag groups were higher than those in the Vehicle group (P<0.05). 4­PBA treatment effectively reduced the apoptotic cell number (P<0.05). In addition, ER swelling and vacuolization in the HiMag + PBA group was reduced compared with that in the HiMag group. In addition, the protein expression levels of GRP78, CHOP, JNK and caspase­12 in the LoMag and HiMag groups were higher than those in the Vehicle group (P<0.05). However, the expression of these four proteins was reduced by 4­PBA treatment (P<0.05). In conclusion, 4­PBA significantly reduced the damage and apoptosis induced by manganese exposure in rats.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Manganês/toxicidade , Animais , Apoptose/efeitos dos fármacos , Caspase 12/metabolismo , Corpo Estriado/química , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Retículo Endoplasmático/química , Retículo Endoplasmático/metabolismo , Proteínas de Choque Térmico/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/ultraestrutura , Fenilbutiratos/farmacologia , Ratos , Ratos Sprague-Dawley , Espectrofotometria Atômica , Fator de Transcrição CHOP/metabolismo
20.
Br J Anaesth ; 123(1): 51-59, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084986

RESUMO

BACKGROUND: Macrophage phagocytosis constitutes an essential part of the host defence against microbes and the resolution of inflammation. Hyperglycaemia during sepsis is reported to reduce macrophage function, and thus, potentiate inflammatory deterioration. We investigated whether high-glucose concentrations augment lipopolysaccharide-induced reduction in macrophage phagocytosis via the endoplasmic stress-C/EBP homologous protein (CHOP) pathway using animal and laboratory investigations. METHODS: Peritoneal macrophages of artificially ventilated male Wistar rats, divided into four groups based on target blood glucose concentrations achieved by glucose administration with or without lipopolysaccharide, were obtained after 24 h. Human macrophages were also cultured in normal or high glucose with or without lipopolysaccharide exposure for 72 h. Changes in the phagocytic activity, intranuclear CHOP expression, and intracellular Akt phosphorylation status of macrophages were evaluated. These changes were also evaluated in human macrophages after genetic knock-down of CHOP by specific siRNA transfection or resolvin D2 treatment. RESULTS: Lipopolysaccharide impaired phagocytosis, increased intranuclear expression of CHOP, and inhibited Akt phosphorylation in both rat peritoneal and human macrophages. Hyperglycaemic glucose concentrations augmented these changes. Genetic knock-down of CHOP restored phagocytic ability and Akt phosphorylation in human macrophages. Furthermore, resolvin D2 co-incubation restored the inhibited phagocytosis and Akt phosphorylation along with the inhibition of intranuclear CHOP expression in human macrophages. CONCLUSIONS: These findings imply that controlling endoplasmic reticulum stress might provide new strategies for restoring reduced macrophage phagocytosis in sepsis-induced hyperglycaemia.


Assuntos
Hiperglicemia/metabolismo , Lipopolissacarídeos/metabolismo , Macrófagos/metabolismo , Fagocitose/fisiologia , Fator de Transcrição CHOP/metabolismo , Adulto , Animais , Células Cultivadas , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/genética , Humanos , Masculino , Ratos , Ratos Wistar , Transdução de Sinais , Fator de Transcrição CHOP/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA