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1.
Anticancer Res ; 39(10): 5515-5524, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570445

RESUMO

BACKGROUND/AIM: Administration of cisplatin in cancer patients is limited by the kidney-related adverse effects; however, a protective strategy is absent. We hypothesized that fucoidan protects the proximal tubule epithelial (TH-1) cells against the effects of cisplatin. MATERIALS AND METHODS: To assess the effect of fucoidan, its effect on reactive oxygen species (ROS) formation, endoplasmic reticulum (ER) stress response, DNA damage response (DDR), apoptosis, and cell-cycle arrest in TH-1 cells was investigated. RESULTS: Cisplatin increased the accumulation of ROS, leading to excessive ER stress. In presence of cisplatin, treatment of TH-1 cells with fucoidan significantly reduced the ER stress by maintaining the complex of GRP78 with PERK and IRE1α. In particular, fucoidan enhanced the antioxidative capacity through up-regulation of PrPC Furthermore, fucoidan suppressed cisplatin-induced apoptosis and cell-cycle arrest, whereas silencing of PRNP blocked these effects of fucoidan. CONCLUSION: Fucoidan may be a potential adjuvant therapy for cancer patients treated with cisplatin as it preserves renal functionality.


Assuntos
Cisplatino/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Túbulos Renais Proximais/efeitos dos fármacos , Polissacarídeos/farmacologia , Substâncias Protetoras/farmacologia , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Túbulos Renais Proximais/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/metabolismo , Regulação para Cima/efeitos dos fármacos , eIF-2 Quinase/metabolismo
2.
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
3.
BMC Plant Biol ; 19(1): 368, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429706

RESUMO

BACKGROUND: We previously reported the involvement of nitric oxide (NO) and cyclic nucleotide-gated ion channel 6 (CNGC6) in the responses of plants to heat shock (HS) exposure. To elucidate their relationship with heat tolerance in Arabidopsis thaliana, we examined the effects of HS on several groups of seedlings: wild type, cngc6, and cngc6 complementation and overexpression lines. RESULTS: After HS exposure, the level of NO was lower in cngc6 seedlings than in wild-type seedlings but significantly elevated in the transgenic lines depending on CNGC6 expression level. The treatment of seeds with calcium ions (Ca2+) enhanced the NO level in Arabidopsis seedlings under HS conditions, whereas treatment with EGTA (a Ca2+ chelator) reduced it, implicating that CNGC6 stimulates the accumulation of NO depending on an increase in cytosolic Ca2+ ([Ca2+]cyt). This idea was proved by phenotypic observations and thermotolerance testing of transgenic plants overexpressing NIA2 and NOA1, respectively, in a cngc6 background. Western blotting indicated that CNGC6 stimulated the accumulation of HS proteins via NO. CONCLUSION: These data indicate that CNGC6 acts upstream of NO in the HS pathway, which improves our insufficient knowledge of the initiation of plant responses to high temerature.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cálcio/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Óxido Nítrico/metabolismo , Termotolerância , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Canais de Cálcio/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Citosol/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico , Mutação , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Plântula/genética , Plântula/metabolismo
4.
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
5.
Nat Commun ; 10(1): 2914, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266968

RESUMO

The deubiquitylase OTUD3 plays a suppressive role in breast tumorigenesis through stabilizing PTEN protein, but its role in lung cancer remains unclear. Here, we demonstrate that in vivo deletion of OTUD3 indeed promotes breast cancer development in mice, but by contrast, it slows down KrasG12D-driven lung adenocarcinoma (ADC) initiation and progression and markedly increases survival in mice. Moreover, OTUD3 is highly expressed in human lung cancer tissues and its higher expression correlates with poorer survival of patients. Further mechanistic studies reveal that OTUD3 interacts with, deubiquitylates and stabilizes the glucose-regulated protein GRP78. Knockdown of OTUD3 results in a decrease in the level of GRP78 protein, suppression of cell growth and migration, and tumorigenesis in lung cancer. Collectively, our results reveal a previously unappreciated pro-oncogenic role of OTUD3 in lung cancer and indicate that deubiquitylases could elicit tumor-suppressing or tumor-promoting activities in a cell- and tissue-dependent context.


Assuntos
Proteínas de Choque Térmico/metabolismo , Neoplasias Pulmonares/enzimologia , Proteases Específicas de Ubiquitina/metabolismo , Animais , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Proteínas de Choque Térmico/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Nus , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteases Específicas de Ubiquitina/genética
6.
Life Sci ; 232: 116602, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251997

RESUMO

AIMS: Blood glucose dysregulation is an adverse factor in the prognosis of hepatocellular carcinoma (HCC). Endoplasmic reticulum (ER) is thought to be crucial component in the development of cancer and diabetes. This study aimed to investigate the mechanisms of poor outcomes in HCC patients with diabetes. MAIN METHODS: ER protein 29 (ERp29) was predicted by proteomics, immunohistochemistry, Western blot, Cell Counting Kit-8 (CCK-8) and cell scratch test were used to identify the expression and biological effects of ERp29 under high glucose (HG) in HCC cells. Bioinformatics found a competing endogenous RNAs (ceRNAs) regulatory network between microRNA-483-3p (miR-483-3p) and Long noncoding RNA (LncRNA MEG3), the above methods also were used to identify their expression, biological effects and their roles of HG on regulation of REp29 in HCC cells, Dual-luciferase reporter assay was carried out to study the interaction of ERp29 with miR-483-3p and miR-483-3p with MEG3. KEY FINDINGS: HG upregulated miR-483-3p expression in HCC cells and miR-483-3p overexpression suppressed ERp29 expression and also increased HCC cell proliferation and migration. Furthermore, we found that MEG3 was decreased in HCC cells incubated in medium with high glucose and knockdown of MEG3 downregulated ERp29 expression. Bioinformatics analysis found that MEG3 mediated its protective effects via binding to miR-483-3p. SIGNIFICANCE: Overall, our study established a novel regulatory network of LncRNA MEG3/miR483-3p/ERp29 in HCC which may be helpful in better understanding the effect of high glucose on poor prognosis of HCC and in exploring new diagnostic and therapeutic tools for managing HCC in patients with diabetes.


Assuntos
Glicemia/metabolismo , Carcinoma Hepatocelular/metabolismo , Diabetes Mellitus/metabolismo , Proteínas de Choque Térmico/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Diabetes Mellitus/sangue , Diabetes Mellitus/patologia , Retículo Endoplasmático/fisiologia , Feminino , Glucose/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Transdução de Sinais
7.
Life Sci ; 231: 116569, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202841

RESUMO

AIM: The IRE1 signaling pathway is implicated in I/R injury. However, little is known about the involvement of this pathway in low-dose LPS treatment of myocardial I/R injury. Thus, an attempt was made to determine the relationship between the IRE1 pathway and I/R injury using rats or in vitro H9C2 cell myocardial I/R injury models. MAIN METHODS: Sprague-Dawley rats and cultured H9C2 cells were pretreated with low-dose LPS and subjected to myocardial I/R injury models. KEY FINDINGS: Low-dose LPS did not affect normal rat or cellular function. Compared with the I/R group, treatment with LPS attenuated myocardial apoptosis, decreased plasma LDH and CK-MB activities, reduced myocardium infarct size, and downregulated caspase-3 expression. Moreover, the protein or mRNA expression levels of the IRE1 signaling pathway-related proteins Grp78, IRE1, p-ASK1, ASK1, p-JNK, and JNK were notably increased during I/R injury but significantly decreased by low-dose LPS treatment both in rats and in H9C2 cells. SIGNIFICANCE: Low-dose LPS exhibited therapeutic effects in myocardial I/R injury. Most importantly, the cardioprotective mechanism of low-dose LPS may be associated with the IRE1 signaling pathway.


Assuntos
Proteínas de Membrana/metabolismo , Isquemia Miocárdica/tratamento farmacológico , Proteínas Serina-Treonina Quinases/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Proteínas de Choque Térmico/metabolismo , Lipopolissacarídeos/farmacologia , MAP Quinase Quinase Quinase 5/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Infarto do Miocárdio/metabolismo , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
8.
Life Sci ; 231: 116551, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31185236

RESUMO

Octreotide (OCT) shows clinical efficacies in the treatment of liver cirrhosis complicated with gastrointestinal hemorrhage. Experiments were designed to investigate its function mechanism associated with endoplasmic reticulum stress (ERS)-induced autophagy and microRNA (miR). Protein associated with ERS and autophagy was detected by western blot. miR-101 was examined by qRT-PCR. Besides, miR-101 or G protein-coupled receptor 78 (GPR78)-silenced Caco-2 cells were established by transfection. Furthermore, western blot was used to determine TGF-beta activated kinase 1 (TAK1), AMPK, mTOR, p70S6K as well as their phosphorylated forms. Lipopolysaccharide (LPS) enforced the expression of GPR78. Besides, LPS triggered the production of Beclin-1 and LC3-II while mitigated the accumulation of p62. Then all these above results were reversed by OCT pretreatment. Moreover, miR-101 expression was downregulated by LPS while upregulated by OCT. Further, miR-101 knockdown strengthened ERS and promoted autophagy. GPR78 silence retarded autophagy process. In the end, OCT mitigated phosphorylation of TAK1, AMPK while enhanced the phosphorylated expression of mTOR and p70S6K in LPS-treated Caco-2 cells. The anti-autophagy property of OCT was mediated by miR-101-induced suppression of GPR78 in LPS-treated Caco-2 cells.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , MicroRNAs/metabolismo , Octreotida/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Proteína Beclina-1/genética , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Estresse do Retículo Endoplasmático/fisiologia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/farmacologia , MicroRNAs/genética , Octreotida/metabolismo , Fosforilação , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
9.
Nat Commun ; 10(1): 2829, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249296

RESUMO

Extracellular vesicles (EVs) are involved in the regulation of cell physiological activity and the reconstruction of extracellular environment. Matrix vesicles (MVs) are a type of EVs released by bone-related functional cells, and they participate in the regulation of cell mineralization. Here, we report bioinspired MVs embedded with black phosphorus (BP) and functionalized with cell-specific aptamer (denoted as Apt-bioinspired MVs) for stimulating biomineralization. The aptamer can direct bioinspired MVs to targeted cells, and the increasing concentration of inorganic phosphate originating from BP can facilitate cell biomineralization. The photothermal effect of the Apt-bioinspired MVs can also promote the biomineralization process by stimulating the upregulated expression of heat shock proteins and alkaline phosphatase. In addition, the Apt-bioinspired MVs display outstanding bone regeneration performance. Our strategy provides a method for designing bionic tools to study the mechanisms of biological processes and advance the development of medical engineering.


Assuntos
Vesículas Extracelulares/metabolismo , Fósforo/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Biomineralização , Osso e Ossos/química , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Vesículas Extracelulares/química , Feminino , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/química , Osteoblastos/metabolismo , Fosfatos/metabolismo , Fósforo/química , Ratos
10.
Food Chem ; 297: 124991, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253316

RESUMO

Plant species differ greatly in their ability to acclimatise to and survive, cold stress. Normally, potato tubers are stored at low temperatures (below 10 °C) to delay sprouting. In this research, combined transcriptomic and proteomic analysis was conducted on potato tubers stored at 15 °C, 4 °C and 0 °C to investigate the mechanism of cold responses during postharvest storage. Results showed that soluble sugars were accumulated under low temperatures, regulating by granule-bound starch synthase 1, beta-amylase, invertase inhibitor and fructokinase. In addition, fifteen heat shock proteins (Hsps), including three Hsp70s, two Hsp80s, one Hsp90, one Hsp100 and eight small Hsps, were induced by low temperatures, which may act individually or synergistically to prevent physiological or cellular damage from cold stress in postharvest potato tubers. This research provided general information of sugar accumulation and defense response in potato tuber under cold storage.


Assuntos
Proteínas de Choque Térmico/metabolismo , Proteínas de Plantas/metabolismo , Solanum tuberosum/metabolismo , Açúcares/metabolismo , Transcriptoma , Temperatura Baixa , Armazenamento de Alimentos , Tubérculos/genética , Tubérculos/metabolismo , Proteômica , Solanum tuberosum/genética , Sintase do Amido/metabolismo , beta-Amilase/metabolismo
11.
Food Chem ; 293: 396-407, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151627

RESUMO

To explore the involvement of protein lysine acetylation in the conversion of muscle to meat, a quantitative analysis of the acetylome in postmortem porcine muscle with or without antemortem stress was conducted. In total, 771 acetylpeptides containing 681 lysine acetylation sites mapping to 176 acetylproteins were identified. Acetylproteins were enriched in muscle contraction, carbohydrate metabolism, cell apoptosis and calcium signaling. Bioinformatic analysis suggests that preslaughter handling may be associated with glycolysis in postmortem muscle and the overall meat quality, via acetylation of multiple enzymes of glycogenolysis/glycolysis, regulate rigor mortis via acetylation of contractile, ATP production and calcium signaling-related proteins, and regulate stress response, cell apoptosis and meat tenderization via regulating the functions of heat shock proteins and permeability transition pore complex. This study provides the first overview of the acetylome in postmortem muscle as affected by preslaughter handling and broadens knowledge of the biochemistry regulating meat quality development.


Assuntos
Qualidade dos Alimentos , Lisina/metabolismo , Músculo Esquelético/metabolismo , Proteômica/métodos , Carne Vermelha/análise , Acetilação , Animais , Biologia Computacional/métodos , Glicólise , Proteínas de Choque Térmico/metabolismo , Proteínas de Carne/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Mudanças Depois da Morte , Estresse Psicológico , Suínos
12.
Int. j. morphol ; 37(2): 522-532, June 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1002254

RESUMO

Amelogenin is one of the enamel matrices secreted by ameloblasts. A mutation of the amelogenin gene can cause hereditary dental enamel defects known as amelogenesis imperfecta (AI). Since lysosome-associated membrane protein-1 (LAMP-1), -3 (LAMP-3), and 78kDa glucose-related protein (Grp78) were identified as binding proteins of amelogenin, several studies have suggested the involvement of these binding proteins with the cell kinetics of ameloblasts in normal or abnormal conditions. The purpose of this study is to investigate the distribution of these amelogenin binding proteins in the ameloblast cell differentiation of mice with a point mutation of the amelogenin gene (Amelx*). The incisors of Amelx* mice had a white opaque color and the tooth surface was observed to be rough under a scanning electron microscope. Among the sequential ameloblast cell differentiation in the Amelx* mice, the shape of ameloblasts at the transition stage was irregular in comparison to those in wild-type (WT) mice. Immunostaining of Grp78 revealed that the whole cytoplasm of the transition stage ameloblasts was immunopositive for Grp78 antibody, while only the distal part of cell was positive in the WT mice. Furthermore, in the Amelx* mice, the cytoplasm of the transition stage ameloblasts was immunopositive for LAMP-1 and LAMP-3. These results suggest that Amelx* may cause the abnormal distribution of amelogenin binding proteins in the cytoplasm of ameloblasts.


La amelogenina es una de las matrices de esmalte secretadas por los ameloblastos. Una mutación del gen de amelogenina puede causar defectos hereditarios del esmalte dental conocidos como amelogénesis imperfecta (AI). Dado que la proteína de membrana asociada a lisosoma-1 (LAMP-1), -3 (LAMP-3) y la proteína relacionada con la glucosa de 78 kDa (Grp78) se identificaron como proteína de unión a amelogenina, varios estudios han sugerido la participación de estas proteínas con la cinética celular de los ameloblastos en condiciones normales o anormales. El objetivo del estudio fue investigar la distribución de LAMP-1, LAM-3 y Grp78 durante la diferenciación celular de ameloblastos de ratones con una mutación puntual del gen de amelogenina (Amelx*). Los incisivos de los ratones Amelx* presentaron un color blanco opaco y se observó en microscopio electrónico de barrido que la superficie del diente era áspera. La diferenciación celular secuencial y la forma de los ameloblastos en la etapa de transición en los ratones Amelx* fue irregular en comparación con los ratones silvestres (RS). La inmunotinción de Grp78 reveló que todo el citoplasma de los ameloblastos en etapa de transición fue inmunopositivo para el anticuerpo Grp78, mientras que solo la parte distal de la célula fue positiva en los ratones RS. Además, en ratones Amelx*, el citoplasma de los ameloblastos en etapa de transición fue inmunopositivo para LAMP-1 y LAMP-3. Estos resultados sugieren que Amelx* puede causar distribución anormal de proteínas de unión a amelogenina en el citoplasma de los ameloblastos.


Assuntos
Animais , Camundongos , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Amelogenina/metabolismo , Amelogênese Imperfeita , Proteínas de Choque Térmico/metabolismo , Microscopia Eletrônica de Varredura , Imunofluorescência , Esmalte Dentário/patologia , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Amelogenina/genética , Proteína 3 de Membrana Associada ao Lisossomo/metabolismo , Incisivo/patologia
13.
Nat Commun ; 10(1): 2393, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160557

RESUMO

Bacterial ClpB and yeast Hsp104 are homologous Hsp100 protein disaggregases that serve critical functions in proteostasis by solubilizing protein aggregates. Two AAA+ nucleotide binding domains (NBDs) power polypeptide translocation through a central channel comprised of a hexameric spiral of protomers that contact substrate via conserved pore-loop interactions. Here we report cryo-EM structures of a hyperactive ClpB variant bound to the model substrate, casein in the presence of slowly hydrolysable ATPγS, which reveal the translocation mechanism. Distinct substrate-gripping interactions are identified for NBD1 and NBD2 pore loops. A trimer of N-terminal domains define a channel entrance that binds the polypeptide substrate adjacent to the topmost NBD1 contact. NBD conformations at the seam interface reveal how ATP hydrolysis-driven substrate disengagement and re-binding are precisely tuned to drive a directional, stepwise translocation cycle.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Caseínas/metabolismo , Endopeptidase Clp/ultraestrutura , Proteínas de Escherichia coli/ultraestrutura , Escherichia coli/metabolismo , Proteínas de Choque Térmico/ultraestrutura , Transporte Proteico , Domínio AAA , Trifosfato de Adenosina/metabolismo , Microscopia Crioeletrônica , Endopeptidase Clp/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Choque Térmico/metabolismo , Hidrólise , Modelos Moleculares , Peptídeos/metabolismo , Agregados Proteicos , Subunidades Proteicas/metabolismo
14.
Croat Med J ; 60(2): 127-140, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31044584

RESUMO

AIM: To propose potential mechanisms of action of electromagnetic fields (EMF) on astrocytes and microglia and to elucidate the role of heat shock proteins (HSP), adenosine triphosphate (ATP), calcium ions (Ca2+), and hypoxia-inducible factor 1α (HIF1α) in neurorestoration following the application of EMF. METHODS: We reviewed the existing studies within the public domain and cross-evaluated their results in order to conclude on the molecular mechanisms of microglia-astrocyte crosstalk at work during EMF treatment. RESULTS: The existing studies suggest that EMF induces the increase of HSP70 expression and inhibition of HIF1α, thus decreasing inflammation and allowing the microglia-astrocyte crosstalk to initiate the formation of a glial scar within the central nervous system. Furthermore, by potentially up-regulating A2A and A3 adenosine receptors, EMF increases cAMP accumulation from astrocytes and reduces the expression of inflammatory cytokines TNF α and IL-8, thus initiating neurorestoration. CONCLUSION: The microglia-astrocyte crosstalk during EMF treatment is crucial for the initiation of neurorestoration. Elucidating the exact mechanisms of EMF actions upon microglia and astrocytes, and its role in neurorestoration could be a key step in further research of the therapeutic potential of EMFs in various neurological disorders.


Assuntos
Astrócitos/fisiologia , Terapia de Campo Magnético , Microglia/fisiologia , Doenças Neurodegenerativas/terapia , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Células Cultivadas , Citocinas , Campos Eletromagnéticos , Proteínas de Choque Térmico/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/metabolismo , Inflamação/terapia , Doenças Neurodegenerativas/imunologia , Receptor Cross-Talk , Fator de Necrose Tumoral alfa
15.
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
16.
Diabetes Res Clin Pract ; 152: 156-165, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31102684

RESUMO

AIM: To investigate the effect of a single and 15 units of high-intensity circuit training (HICT) programme on glucose metabolism, myokines' response and selected genes' expression in women. METHODS: Thirty-three, non-active women (mean age: 38 ±â€¯12) were split into a HICT (n = 20) or a control group (CON, n = 13). The training protocol included three circuits of nine exercises with own body weight as a workload performed 3 times a week for five weeks. The CON group performed HICT twice. Blood samples were taken before, 1 h and 24 h after the first and last unit to determine IGF-1, myostatin, irisin, decorin, HSP27, interleukin-15 concentrations using the ELISA immunoenzymatic method. To evaluate HSPB1, TNF-α and DCN mRNA, real-time PCR was used. Pre- and post-intervention, the oral glucose test and body composition assessment were completed. RESULTS: The following parameters tended to decrease after the 5-week HICT program: insulin and HOMA-IR Training diminished insulin/IGF-1 ratio (51% CI: -63% to -34%) and induced the drop of myostatin concentration but significantly only among middle-aged women and at baseline insulin resistance. CONCLUSION: Obtained data revealed that HICT improved an insulin sensitivity and diminished myostatin concentration among older, insulin-resistant women with lower baseline physical capacity.


Assuntos
Envelhecimento/fisiologia , Exercícios em Circuitos , Terapia por Exercício/métodos , Tolerância ao Exercício/fisiologia , Resistência à Insulina/fisiologia , Aptidão Física/fisiologia , Adulto , Fatores Etários , Glicemia/metabolismo , Composição Corporal/fisiologia , Exercícios em Circuitos/métodos , Decorina/genética , Decorina/metabolismo , Metabolismo Energético/genética , Exercício/fisiologia , Feminino , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Pessoa de Meia-Idade , Miostatina/genética , Miostatina/metabolismo , Treinamento de Resistência/métodos , Adulto Jovem
17.
Chemosphere ; 228: 685-693, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31063915

RESUMO

Di-(2-ethylhexyl) phthalate (DEHP) is a widespread environmental toxicant that severely impacts agricultural production and animal and human health. Nevertheless, DEHP-induced hepatotoxicity at the molecular level in quail remains unexplored. The heat shock response (HSR), involving heat shock proteins (HSPs) and heat shock transcription factors (HSFs), is a highly conserved molecular response that is triggered by stressors, especially exposure to toxicants. To explore the DEHP-induced hepatotoxicity that occurs via regulation of HSR in birds, female quail were dosed with DEHP by oral gavage (0, 250, 500 and 1000 mg/kg) for 45 days. Based on histopathological analysis, the livers of the DEHP-treated groups exhibited structural alterations of hepatocytes, including mitochondrial swelling, derangement of hepatic plates, inflammatory cell infiltration and adipose degeneration. Ultrastructural evaluation of the livers of DEHP-treated quail revealed swollen mitochondria, partial disappearance of mitochondrial membranes and cristae, nuclear chromatin margination and nuclear condensation. The expression of HSF1 and HSF3 significantly decreased after DEHP exposure. The levels of HSPs (HSP10, HSP25, HSP27, HSP40, HSP47, HSP60, HSP70 and HSP90) were significantly downregulated in the livers of DEHP-treated quail. In this study, we concluded that DEHP exposure resulted in liver function damage and hepatotoxicity by reducing the expression of HSFs and HSPs in quail liver, which inhibited the protective effect of the HSR signaling pathway.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Coturnix/fisiologia , Dietilexilftalato/toxicidade , Resposta ao Choque Térmico/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Ecotoxicologia/métodos , Poluentes Ambientais/toxicidade , Feminino , Proteínas de Choque Térmico/metabolismo , Humanos , Fígado/patologia , Fígado/ultraestrutura , Transdução de Sinais/efeitos dos fármacos
18.
J Plant Physiol ; 238: 12-19, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31121523

RESUMO

In this study, the effect of 24-Epibrassinolide (EBL) on antioxidant system in Arabidopsis thaliana were investigated under arsenate [As(V)] stress. The enzyme activity of superoxide dismutase (SOD) and catalase (CAT), total antioxidant status, malondialdehyde (MDA) level and free proline content, as well as the expression levels of SOD isoforms (Cu-ZnSODs, FeSODs and MnSOD), CAT isoforms (CAT1, CAT2 and CAT3), some heat shock proteins (Hsp70-4 and Hsp90-1) and proline biosynthesis (P5CS1 and P5CS2) genes were determined in rosette leaves of eight-week old plants under exposure of 100 and 200 µM As(V) and/or 1 µM EBL treatments for 24 h. Total SOD and CAT enzyme activities increased as a result of 100 µM As(V) + EBL treatments compared to 100 µM As(V) treatment. Total antioxidant and proline levels increased in plants subjected to As(V), and the treatment of EBL together with stress caused further increase. As the MDA level increased in As-treated plants, 100 µM As(V) + EBL treatment decreased MDA level. Transcript levels of CSD1, CSD2, FSD1, FSD2, MSD1 and CAT2 genes increased as a result of combined treatment of EBL and As(V) compared to control and alone stress treatments (except CSD1 gene). Expression level of CSD3, CAT1 and CAT3 genes were downregulated in response to As(V) and/or EBL treatments. EBL application alone and in combination with As(V) elevated the expression level of P5CS1 gene dramatically. Treatment with 100 µM As(V) and EBL increased the transcript level of Hsp70-4 and Hsp90-1 genes in leaves compared to 100 µM As(V) treatment. To our best knowledge, this is the first detailed study to evaluate the improving effect of EBL on antioxidant defense system at biochemical and transcriptional level in A. thaliana plants under As(V) stress.


Assuntos
Arabidopsis/metabolismo , Arsênico/toxicidade , Brassinosteroides/farmacologia , Esteroides Heterocíclicos/farmacologia , Arabidopsis/efeitos dos fármacos , Catalase/metabolismo , Relação Dose-Resposta a Droga , Proteínas de Choque Térmico/metabolismo , Malondialdeído/metabolismo , Prolina/metabolismo , Isoformas de Proteínas , Estresse Fisiológico/efeitos dos fármacos , Superóxido Dismutase/metabolismo
19.
Plant Sci ; 284: 117-126, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084864

RESUMO

Previously, we showed that transplastomic tobacco plants expressing the LiHsp83-SAG1 fusion protein displayed a chlorotic phenotype and growth retardation, while plants expressing the SAG1 and GRA4 antigens alone did not. We conducted a comprehensive examination of the metabolic and photosynthetic parameters that could be affecting the normal growth of LiHsp83-SAG1 plants in order to understand the origin of these pleiotropic effects. These plants presented all photosynthetic pigments and parameters related to PSII efficiency significantly diminished. However, the expression of CHLI, RSSU and LHCa/b genes did not show significant differences between LiHsp83-SAG1 and control plants. Total protein, starch, and soluble sugar contents were also greatly reduced in LiHsp83-SAG1 plants. Since Hsp90 s are constitutively expressed at much higher concentrations at high temperatures, we tested if the fitness of LiHsp83-SAG1 over-expressing LiHsp83 would improve after heat treatment. LiHsp83-SAG1 plants showed an important alleviation of their phenotype and an evident recovery of the PSII function. As far as we know, this is the first report where it is demonstrated that a transplastomic line performs much better at higher temperatures. Finally, we detected that LiHsp83-SAG1 protein could be binding to key photosynthesis-related proteins at 37 °C. Our results suggest that the excess of this molecular chaperone could benefit the plant in a possible heat shock and prevent the expected denaturation of proteins. However, the LiHsp83-SAG1 protein content was weakly decreased in heat-treated plants. Therefore, we cannot rule out that the alleviation observed at 37 °C may be partially due to a reduction of the levels of the recombinant protein.


Assuntos
Antígenos de Protozoários/metabolismo , Proteínas de Choque Térmico/metabolismo , Leishmania infantum/metabolismo , Fotossíntese , Plantas Geneticamente Modificadas/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Toxoplasma/metabolismo , Clorofila/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Perfilação da Expressão Gênica , Temperatura Alta , Imunoprecipitação , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/parasitologia , Tabaco
20.
BMC Genomics ; 20(1): 325, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31035922

RESUMO

BACKGROUND: Water deficit and soil salinity substantially influence plant growth and productivity. When occurring individually, plants often exhibit reduced growth resulting in yield losses. The simultaneous occurrence of these stresses enhances their negative effects. Unraveling the molecular mechanisms of combined abiotic stress responses is essential to secure crop productivity under unfavorable environmental conditions. RESULTS: This study examines the effects of water deficit, salinity and a combination of both on growth and transcriptome plasticity of barley seminal roots by RNA-Seq. Exposure to water deficit and combined stress for more than 4 days significantly reduced total seminal root length. Transcriptome sequencing demonstrated that 60 to 80% of stress type-specific gene expression responses observed 6 h after treatment were also present after 24 h of stress application. However, after 24 h of stress application, hundreds of additional genes were stress-regulated compared to the short 6 h treatment. Combined salt and water deficit stress application results in a unique transcriptomic response that cannot be predicted from individual stress responses. Enrichment analyses of gene ontology terms revealed stress type-specific adjustments of gene expression. Further, global reprogramming mediated by transcription factors and consistent over-representation of basic helix-loop-helix (bHLH) transcription factors, heat shock factors (HSF) and ethylene response factors (ERF) was observed. CONCLUSION: This study reveals the complex transcriptomic responses regulating the perception and signaling of multiple abiotic stresses in barley.


Assuntos
Hordeum/genética , Estresse Salino , Reprogramação Celular , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Hordeum/crescimento & desenvolvimento , Fenótipo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , RNA de Plantas/química , RNA de Plantas/metabolismo , Análise de Sequência de RNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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