Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 8.755
Filtrar
1.
Int Heart J ; 61(5): 1022-1033, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32999189

RESUMO

Cardiac hypertrophy is one of the significant risk factors that result in maladaptive cardiac remodeling and heart failure, and exercise is known to exert cardioprotection. In this research, the cardioprotective function and exercise mechanisms were explored.The rats underwent transverse aortic constriction (TAC) or a sham operation. The rats that received TAC were randomly assigned to five groups: (1) rats subjected to a sham operation as control group (SC), (2) rats that underwent TAC group (TC), (3) TAC and moderate-intensity exercise group (TE), (4) TE plus 3-MA group (TEM), and (5) TE plus Compound C group (TEC). The heart function was measured via echocardiography. Histological analysis and relative protein testing were conducted to analyze collagen deposition and apoptosis. Furthermore, western blot was employed to measure the protein expression of relevant signaling pathways. Impaired cardiac function, interstitial fibrosis, enhanced apoptosis, and ER stress were observed in the TAC-induced left ventricular hypertrophy. Exercise attenuated TAC-induced cardiac dysfunction, interstitial fibrosis, and ER stress-related apoptosis. In addition, exercise significantly improved autophagy and upregulated AMPK phosphorylation. Furthermore, AMPK inhibitor Compound C repressed the activation of AMPK, and autophagy inhibitor 3-methyladenine reversed exercise-induced autophagy. All of these abolished the protection of exercise against cardiac dysfunction and fibrosis induced by TAC.Our results indicated that 4 weeks of treadmill exercise could alleviate pressure overload-induced LV dysfunction and remodeling via an autophagy-dependent mechanism, which was induced by enhancing autophagy through the activation of AMPK.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Hipertrofia Ventricular Esquerda/reabilitação , Condicionamento Físico Animal/fisiologia , Disfunção Ventricular Esquerda/reabilitação , Animais , Apoptose , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Feminino , Distribuição Aleatória , Ratos Wistar , Remodelação Ventricular
2.
Medicine (Baltimore) ; 99(40): e22544, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019464

RESUMO

BACKGROUND: Clinical studies have shown that celecoxib can significantly inhibit the development of tumors, and basic experiments and in vitro experiments also provide a certain basis, but it is not clear how celecoxib inhibits tumor development in detail. METHODS: A literature search of all major academic databases was conducted (PubMed, China National Knowledge Internet (CNKI), Wan-fang, China Science and Technology Journal Database (VIP), including the main research on the mechanisms of celecoxib on tumors. RESULTS: Celecoxib can intervene in tumor development and reduce the formation of drug resistance through multiple molecular mechanisms. CONCLUSION: Celecoxib mainly regulates the proliferation, migration, and invasion of tumor cells by inhibiting the cyclooxygenases-2/prostaglandin E2 signal axis and thereby inhibiting the phosphorylation of nuclear factor-κ-gene binding, Akt, signal transducer and activator of transcription and the expression of matrix metalloproteinase 2 and matrix metalloproteinase 9. Meanwhile, it was found that celecoxib could promote the apoptosis of tumor cells by enhancing mitochondrial oxidation, activating mitochondrial apoptosis process, promoting endoplasmic reticulum stress process, and autophagy. Celecoxib can also reduce the occurrence of drug resistance by increasing the sensitivity of cancer cells to chemotherapy drugs.


Assuntos
Celecoxib/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Celecoxib/efeitos adversos , Celecoxib/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Dinoprostona/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Metaloproteinase 2 da Matriz/efeitos dos fármacos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
Nat Commun ; 11(1): 4677, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938929

RESUMO

The Integrated Stress Response (ISR) helps metazoan cells adapt to cellular stress by limiting the availability of initiator methionyl-tRNA for translation. Such limiting conditions paradoxically stimulate the translation of ATF4 mRNA through a regulatory 5' leader sequence with multiple upstream Open Reading Frames (uORFs), thereby activating stress-responsive gene expression. Here, we report the identification of two critical regulators of such ATF4 induction, the noncanonical initiation factors eIF2D and DENR. Loss of eIF2D and DENR in Drosophila results in increased vulnerability to amino acid deprivation, susceptibility to retinal degeneration caused by endoplasmic reticulum (ER) stress, and developmental defects similar to ATF4 mutants. eIF2D requires its RNA-binding motif for regulation of 5' leader-mediated ATF4 translation. Consistently, eIF2D and DENR deficient human cells show impaired ATF4 protein induction in response to ER stress. Altogether, our findings indicate that eIF2D and DENR are critical mediators of ATF4 translational induction and stress responses in vivo.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Estresse do Retículo Endoplasmático/genética , Fatores de Iniciação em Eucariotos/genética , Biossíntese de Proteínas , Fatores de Transcrição/genética , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Sítios de Ligação , Linhagem Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Humanos , Mutação , Fases de Leitura Aberta , Interferência de RNA , Degeneração Retiniana/genética , Fatores de Transcrição/metabolismo
4.
J Toxicol Sci ; 45(9): 589-598, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32879258

RESUMO

Acute mercury chloride (HgCl2) poisoning may lead to kidney injury, but the underlying mechanism remains largely unknown. Endoplasmic reticulum (ER) stress plays a role in some heavy metal poisoning. Whether it mediates kidney injury in acute HgCl2 poisoning remains unknown. In this study, we examined the kidney injury and the corresponding ER stress in the mouse model of different doses of acute HgCl2 poisoning. To further confirm the role of ER stress, we tested the effects of its chemical chaperone [4-phenylbutyric acid (4-PBA)]. The results revealed that acute HgCl2 poisoning caused more severe kidney injury with dose on and activated ER stress, as indicated by increased expression of GRP78 and CHOP. Inhibition of ER stress restored the functional and morphological changes of kidneys, and partly attenuated renal tubular epithelial cell apoptosis. In summary, ER stress contributes to the acute kidney injury following HgCl2 poisoning, and inhibition of ER stress may alleviate the kidney injury via reducing apoptosis.


Assuntos
Lesão Renal Aguda/etiologia , Estresse do Retículo Endoplasmático/fisiologia , Cloreto de Mercúrio/envenenamento , Animais , Butilaminas , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/genética , Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
5.
Nat Commun ; 11(1): 4798, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968066

RESUMO

Myeloid cells are known mediators of hypertension, but their role in initiating renin-induced hypertension has not been studied. Vitamin D deficiency causes pro-inflammatory macrophage infiltration in metabolic tissues and is linked to renin-mediated hypertension. We tested the hypothesis that impaired vitamin D signaling in macrophages causes hypertension using conditional knockout of the myeloid vitamin D receptor in mice (KODMAC). These mice develop renin-dependent hypertension due to macrophage infiltration of the vasculature and direct activation of renal juxtaglomerular (JG) cell renin production. Induction of endoplasmic reticulum stress in knockout macrophages increases miR-106b-5p secretion, which stimulates JG cell renin production via repression of transcription factors E2f1 and Pde3b. Moreover, in wild-type recipient mice of KODMAC/miR106b-/- bone marrow, knockout of miR-106b-5p prevents the hypertension and JG cell renin production induced by KODMAC macrophages, suggesting myeloid-specific, miR-106b-5p-dependent effects. These findings confirm macrophage miR-106b-5p secretion from impaired vitamin D receptor signaling causes inflammation-induced hypertension.


Assuntos
Hipertensão Renal/metabolismo , Hipertensão/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Nefrite/metabolismo , Renina/metabolismo , Animais , Medula Óssea , Transplante de Medula Óssea , Modelos Animais de Doenças , Fator de Transcrição E2F1/metabolismo , Estresse do Retículo Endoplasmático , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides , Receptores de Calcitriol , Vitamina D
6.
Am J Chin Med ; 48(6): 1435-1454, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32907363

RESUMO

Endoplasmic reticulum stress (ER stress) plays a main role in pancreatic [Formula: see text]-cell dysfunction and death because of intracellular Ca[Formula: see text] turbulence and inflammation activation. Although several drugs are targeting pancreatic [Formula: see text]-cell to improve [Formula: see text]-cell function, there still lacks agents to alleviate [Formula: see text]-cell ER stress conditions. Therefore we used thapsigargin (THAP) or high glucose (HG) to induce ER stress in [Formula: see text]-cell and aimed to screen natural molecules against ER stress-induced [Formula: see text]-cell dysfunction. Through screening the Traditional Chinese drug library ([Formula: see text] molecules), luteolin was finally discovered to improve [Formula: see text]-cell function. Cellular viability results indicated luteolin reduced the THAP or HG-induced [Formula: see text]-cell death and apoptosis through MTT and flow cytometry assay. Moreover, luteolin improved [Formula: see text]-cell insulin secretion ability under ER stress conditions. Also ER stress-induced intracellular Ca[Formula: see text] turbulence and inflammation activation were inhibited by luteolin treatment. Mechanically, luteolin inhibited HNF4[Formula: see text] signaling, which was induced by ER stress. Moreover, luteolin reduced the transcriptional level of HNF4[Formula: see text] downstream gene, such as Asnk4b and HNF1[Formula: see text]. Conversely HNF4[Formula: see text] knockdown abolished the effect of luteolin on [Formula: see text]-cell using siRNA. These results suggested the protective effect of luteolin on [Formula: see text]-cell was through HNF4[Formula: see text]/Asnk4b pathway. In conclusion, our study discovered that luteolin improved [Formula: see text]-cell function and disclosed the underlying mechanism of luteolin on [Formula: see text]-cell, suggesting luteolin is a promising agent against pancreatic dysfunction.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/fisiologia , Luteolina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Tapsigargina/efeitos adversos , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Morte Celular/efeitos dos fármacos , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Estresse do Retículo Endoplasmático/fisiologia , Glucose/efeitos adversos , Células Secretoras de Insulina/metabolismo , Luteolina/isolamento & purificação
7.
Environ Health Prev Med ; 25(1): 53, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917140

RESUMO

BACKGROUND: Pilea umbrosa (Urticaceae) is used by local communities (district Abbotabad) for liver disorders, as anticancer, in rheumatism and in skin disorders. METHODS: Methanol extract of P. umbrosa (PUM) was investigated for the presence of polyphenolic constituents by HPLC-DAD analysis. PUM (150 mg/kg and 300 mg/kg) was administered on alternate days for eight weeks in rats exposed with carbon tetrachloride (CCl4). Serum analysis was performed for liver function tests while in liver tissues level of antioxidant enzymes and biochemical markers were also studied. In addition, semi quantitative estimation of antioxidant genes, endoplasmic reticulum (ER) induced stress markers, pro-inflammatory cytokines and fibrosis related genes were carried out on liver tissues by RT-PCR analysis. Liver tissues were also studied for histopathological injuries. RESULTS: Level of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and glutathione (GSH) decreased (p < 0.05) whereas level of thiobarbituric acid reactive substance (TBARS), H2O2 and nitrite increased in liver tissues of CCl4 treated rat. Likewise increase in the level of serum markers; alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and total bilirubin was observed. Moreover, CCl4 caused many fold increase in expression of ER stress markers; glucose regulated protein (GRP-78), x-box binding protein1-total (XBP-1 t), x-box binding protein1-unspliced (XBP-1 u) and x-box binding protein1-spliced (XBP-1 s). The level of inflammatory mediators such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) was aggregated whereas suppressed the level of antioxidant enzymes; γ-glutamylcysteine ligase (GCLC), protein disulfide isomerase (PDI) and nuclear erythroid 2 p45-related factor 2 (Nrf-2). Additionally, level of fibrosis markers; transforming growth factor-ß (TGF-ß), Smad-3 and collagen type 1 (Col1-α) increased with CCl4 induced liver toxicity. Histopathological scrutiny depicted damaged liver cells, neutrophils infiltration and dilated sinusoids in CCl4 intoxicated rats. PUM was enriched with rutin, catechin, caffeic acid and apigenin as evidenced by HPLC analysis. Simultaneous administration of PUM and CCl4 in rats retrieved the normal expression of these markers and prevented hepatic injuries. CONCLUSION: Collectively these results suggest that PUM constituted of strong antioxidant chemicals and could be a potential therapeutic agent for stress related liver disorders.


Assuntos
Tetracloreto de Carbono/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fibrose/tratamento farmacológico , Inflamação/tratamento farmacológico , Substâncias Protetoras/farmacologia , Urticaceae/química , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fibrose/genética , Inflamação/genética , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
8.
Adv Exp Med Biol ; 1274: 71-99, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32894508

RESUMO

Bioactive lipid mediators resulting from the metabolism of polyunsaturated fatty acids (PUFA) are controlled by many pathways that regulate the levels of these mediators and maintain homeostasis to prevent disease. PUFA metabolism is driven primarily through three pathways. Two pathways, the cyclooxygenase (COX) and lipoxygenase (LO) enzymatic pathways, form metabolites that are mostly inflammatory, while the third route of metabolism results from the oxidation by the cytochrome P450 enzymes to form hydroxylated PUFA and epoxide metabolites. These epoxygenated fatty acids (EpFA) demonstrate largely anti-inflammatory and beneficial properties, in contrast to the other metabolites formed from the degradation of PUFA. Dysregulation of these systems often leads to chronic disease. Pharmaceutical targets of disease focus on preventing the formation of inflammatory metabolites from the COX and LO pathways, while maintaining the EpFA and increasing their concentration in the body is seen as beneficial to treating and preventing disease. The soluble epoxide hydrolase (sEH) is the major route of metabolism of EpFA. Inhibiting its activity increases concentrations of beneficial EpFA, and often disease states correlate to mutations in the sEH enzyme that increase its activity and decrease the concentrations of EpFA in the body. Recent approaches to increasing EpFA include synthetic mimics that replicate biological activity of EpFA while preventing their metabolism, while other approaches focus on developing small molecule inhibitors to the sEH. Increasing EpFA concentrations in the body has demonstrated multiple beneficial effects in treating many diseases, including inflammatory and painful conditions, cardiovascular disease, neurological and disease of the central nervous system. Demonstration of efficacy in so many disease states can be explained by the fundamental mechanism that EpFA have of maintaining healthy microvasculature and preventing mitochondrial and endoplasmic reticulum stress. While there are no FDA approved methods that target the sEH or other enzymes responsible for metabolizing EpFA, current clinical efforts to test for efficacy by increasing EpFA that include inhibiting the sEH or administration of EpFA mimics that block metabolism are in progress.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Estresse do Retículo Endoplasmático , Ácidos Graxos/metabolismo , Inflamação/tratamento farmacológico , Mitocôndrias/patologia , Terapia de Alvo Molecular , Manejo da Dor , Doenças Cardiovasculares/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Inflamação/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Dor
9.
Zhongguo Zhong Yao Za Zhi ; 45(16): 3915-3921, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32893589

RESUMO

This study aimed to investigate the effect and possible mechanism of Bidens pilosa decoction on non-alcoholic fatty liver disease(NAFLD) induced by high fat and high glucose in mice. Bald/c mice were randomly divided into normal group, model group, metformin(200 mg·kg~(-1)) treatment group, Bidens pilosa decoction(10 g·kg~(-1)) treatment group, metformin and B. pilosa decoction(100 mg·kg~(-1)+5 g·kg~(-1)) treatment group. Except for the normal group, mice in the other four groups were fed with high-fat and high-glucose diet for 8 weeks to establish the non-alcoholic fatty liver model. After 4 weeks of treatment, blood was collected from the eyeballs, the mice were sacrificed, and relevant indicators were detected. The results showed that compared with the model group, blood lipid and blood glucose levels of each treatment group were significantly lower(P<0.05); HE staining results showed that liver pathological damage in each treatment group was significantly improved; oil red O staining results showed fat distribution in each treatment group significantly reduced(P<0.01); immunohistochemical staining showed that glucose regulated the protein expression of protein 78(GRP78) in liver tissues of each treatment group was also significantly reduced(P<0.01); Western blot results showed that endoplasmic reticulum stress signal pathway-related factors GRP78, phosphorylated-protein kinase R-like ER kinase(p-PERK), eukaryotic translation-initiation factor 2α(eIF2α), activating transcription factor 4(ATF4), C/EBP homologous protein(Chop), inositol requiring 1α(IRE1α), and cleaved-cysteinyl aspartate specific proteinase 12(cleaved-caspase-12) were significantly reduced(P<0.01). The results of the combined drug treatment group were better than those of the single drug treatment group. These results showed that B. pilosa decoction had the effect in improving non-alcoholic fatty liver, and its mechanism may be related to the down-regulation of the expression of endoplasmic reticulum stress(ERS)-related factors, and the reduction of the apoptosis of hepatocytes caused by ERS and the down-regulation of blood lipid and blood glucose levels.


Assuntos
Bidens , Hepatopatia Gordurosa não Alcoólica , Animais , Apoptose , Estresse do Retículo Endoplasmático , Endorribonucleases , Glucose , Camundongos , Proteínas Serina-Treonina Quinases
10.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(5): 632-639, 2020 May 30.
Artigo em Chinês | MEDLINE | ID: mdl-32897203

RESUMO

OBJECTIVE: To investigate the role of endoplasmic reticulum (ER)-stress of Kupffer cells (KCs) and KCs-derived tumor necrosis factor-α (TNF-α) in medicating apoptosis of hepatic stellate cell (HSC). METHODS: Sixty male SD rats were randomized into control group, model group, ER- stress group, depletion group and KCs block group (n=15). The 4 groups of rats were given intraperitoneal injections (twice a week for 8 weeks) of normal saline (2 mg/kg); 40% CCl4 solution (in peanut oil, 2 mg/kg); 40% CCl4 solution (2 mg/kg) and tunicamycin (1 mg/kg); and 40% CCl4 solution (2 mg/kg) and tunicamycin (1 mg/kg) followed by clodronate liposomes (50 mg/kg), respectively. After the treatments, samples of the liver tissue and serum were collected from the rats from the 4 groups to isolate KC cells, which were co-cultured with LX2 cells. In the depletion group, the rats were injected with anti-rat TNFR mAb (0.35 mg/kg) via the portal vein before isolating the KCs. Liver function examination, Eirius red staining, ELISA, immuno- histochemical staining, and RT-PCR were performed to assess the liver function, liver fibrosis, KC phenotypes, expression of the in fl ammatory factors, and the number of active HSC was detected. The isolated KCs were treated with tunicamycin before co-culture with LX2 cells, and ELISA, RT-PCR and Western blot were performed to examine KC phenotypes, in fl ammatory factors, LX2 cell apoptosis and TNFR/caspase8 pathway activity. RESULTS: Compared with the rats in the control group, the rats in the model group had significantly increased ALT and AST levels, Sirius red staining-positive area, and Desmin-positive cells (activated HSCs) (P < 0.05) with significantly lowered number of CD16-positive KCs (M1), and TNF-α protein and mRNA expression (P < 0.05). Compared with those in the model group, the rats in ER-stress group showed significantly decreased ALT and AST levels, Sirius red staining positivity and Desmin-positive cells (P < 0.05) and increased number of CD16-positive KCs and TNF-α expressions (P < 0.05). In the depletion group, compared with the ER-stress group, the rats had significantly increased ALT and AST levels of, Sirius red staining positivity and Desmin-positive cells (P < 0.05) and reduced CD16- positive KCs and TNF-αexpressions (P < 0.05). In the cell co-culture experiment, the model group showed significantly reduced TUNEL-positive LX2 cells, CD16-positive cells, and expressions of TNFR1, cleaved caspase- 8 and cleaved caspase- 3 in the KCs (P < 0.05) with increased Desmin-positive LX2 cells (P < 0.05). Compared with the model group, the ER- stress group exhibited significantly increased TUNEL-positive LX2 cells, CD16-positive cells and expressions of TNFR, cleaved caspase-8 and cleaved caspase-3 in the KCs (P < 0.05) and decreased Desmin-positive LX2 cells (P < 0.05). In the depletion group, blocking TNFR resulted in significantly decreased expressions of cleaved caspase-8 and cleaved caspase-3 compared with those in ER- stress group (P < 0.05) although there was no significant changed in TNFR expression. CONCLUSIONS: ER stress of KCs promotes the transformation of KCs towards M1 phenotype and increases the expression of TNF-α, which triggers the apoptosis of HSCs through the TNFR/caspase-8 pathway.


Assuntos
Estresse do Retículo Endoplasmático , Células Estreladas do Fígado , Macrófagos do Fígado , Animais , Apoptose , Caspase 8 , Masculino , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa
11.
Nat Commun ; 11(1): 4254, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848143

RESUMO

Pulmonary fibrosis (PF) is a major public health problem with limited therapeutic options. There is a clear need to identify novel mediators of PF to develop effective therapeutics. Here we show that an ER protein disulfide isomerase, thioredoxin domain containing 5 (TXNDC5), is highly upregulated in the lung tissues from both patients with idiopathic pulmonary fibrosis and a mouse model of bleomycin (BLM)-induced PF. Global deletion of Txndc5 markedly reduces the extent of PF and preserves lung function in mice following BLM treatment. Mechanistic investigations demonstrate that TXNDC5 promotes fibrogenesis by enhancing TGFß1 signaling through direct binding with and stabilization of TGFBR1 in lung fibroblasts. Moreover, TGFß1 stimulation is shown to upregulate TXNDC5 via ER stress/ATF6-dependent transcriptional control in lung fibroblasts. Inducing fibroblast-specific deletion of Txndc5 mitigates the progression of BLM-induced PF and lung function deterioration. Targeting TXNDC5, therefore, could be a novel therapeutic approach against PF.


Assuntos
Fibrose Pulmonar Idiopática/etiologia , Fibrose Pulmonar Idiopática/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Tiorredoxinas/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Bleomicina/toxicidade , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático , Deleção de Genes , Humanos , Fibrose Pulmonar Idiopática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Isomerases de Dissulfetos de Proteínas/genética , Dobramento de Proteína , Estabilidade Proteica , Fibrose Pulmonar/patologia , Receptor do Fator de Crescimento Transformador beta Tipo I/química , Transdução de Sinais , Tiorredoxinas/antagonistas & inibidores , Tiorredoxinas/genética , Regulação para Cima
13.
Orv Hetil ; 161(35): 1449-1455, 2020 08.
Artigo em Húngaro | MEDLINE | ID: mdl-32822323

RESUMO

Autophagy plays an important role in the homeostasis of the cells and it may be upregulated in response to several types of stresses. Deregulation of autophagy is a key mechanism in the pathogenesis and progression of several liver diseases. Deficient autophagy can contribute to liver steatosis, to endoplasmic reticulum stress and to the progression of non-alcoholic fatty liver disease. Chronic alcohol consumption inhibits autophagy. The accumulated mutant protein in the endoplasmic reticulum can be degraded by autophagy in alpha-1-antitrypsin deficiency. Hepatitis C and B viruses may exploit the autophagy pathway to promote the own replication. Hepatitis C virus non-structural protein 5A and 5B have roles in the induction of autophagosomes. MicroRNAs regulate multiple physiological, pathological functions and autophagy through the modulation of gene expression. MicroRNA-122 is involved in HCV replication. In HBV-infected livers, the microRNA pathways related to cell death, DNA damage, recombination and signal transduction were activated. MicroRNA-122 effects multiple important factors which regulate the lipid and carbohydrate metabolisms in human non-alcoholic fatty liver disease. Oxidative stress and free oxygen radicals generation involved in alcoholic liver diseases development are regulated by microRNAs through different pathways. MicroRNAs control autophagy process and autophagy regulates the expression of microRNA-s. The exploration of their interactions contributes to understanding the development of liver diseases. Orv Hetil. 2020; 161(35): 1499-1455.


Assuntos
Autofagia , Carcinoma Hepatocelular/patologia , Hepacivirus/patogenicidade , Hepatite C Crônica/patologia , Hepatite C , Fígado/virologia , MicroRNAs/genética , Carcinoma Hepatocelular/virologia , Estresse do Retículo Endoplasmático , Hepacivirus/fisiologia , Hepatite C Crônica/virologia , Hepatite Viral Humana/fisiopatologia , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Estresse Oxidativo
14.
Med Hypotheses ; 143: 110148, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32759016

RESUMO

Estrogen hormone acts as a potential key player in providing immunity against certain viral infection. It is found to be associated in providing immunity against acute lungs inflammation and influenza virus by modulating cytokines storm and mediating adaptive immune alterations respectively. Women are less affected by SARS-CoV-2 infection because of the possible influence of estrogen hormone as compared to men. We hypothesized that SARS-CoV-2 causes stress in endoplasmic reticulum (ER) which in turn aggravates the infection, estrogen hormone might play key role in decreasing ER stress by activating estrogen mediated signaling pathways, results in unfolded protein response (UPR). Estrogen governs degradation of phosphotidylinositol 4,5-bisphosphate (PIP2) into diacylglycerol (DAG) and inositol triphosphate (IP3) with the help of phospholipase C. IP3 start in-fluxing Ca+2 ions that helps in UPR activation. To support our hypothesis, we analyzed the data of 162,392 COVID-19 patients to determine the relation of this disease with gender. We observed that 26% of women and 74% of men were affected by SARS-CoV-2. It indicated that women are less affected because of the possible influence of estrogen hormone in women.


Assuntos
Betacoronavirus , Infecções por Coronavirus/fisiopatologia , Estresse do Retículo Endoplasmático/fisiologia , Estrogênios/fisiologia , Modelos Biológicos , Pandemias , Pneumonia Viral/fisiopatologia , Adulto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/metabolismo , Conjuntos de Dados como Assunto/estatística & dados numéricos , Diglicerídeos/metabolismo , Resistência à Doença , Feminino , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Fosfatidilinositol 4,5-Difosfato/metabolismo , Pneumonia Viral/epidemiologia , Pneumonia Viral/metabolismo , Caracteres Sexuais , Distribuição por Sexo , Transdução de Sinais , Fosfolipases Tipo C/metabolismo , Resposta a Proteínas não Dobradas , Proteínas Virais/biossíntese , Proteínas Virais/genética
15.
PLoS One ; 15(8): e0237669, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810137

RESUMO

Pancreatic beta cell death is a hallmark of type 1 and 2 diabetes (T1D/T2D), but the underlying molecular mechanisms are incompletely understood. Key proteins of the DNA damage response (DDR), including tumor protein P53 (P53, also known as TP53 or TRP53 in rodents) and Ataxia Telangiectasia Mutated (ATM), a kinase known to act upstream of P53, have been associated with T2D. Here we test and compare the effect of ATM and P53 ablation on beta cell survival in the rat beta cell line Ins1E. We demonstrate that ATM and P53 differentially regulate beta cell apoptosis induced upon fundamentally different types of diabetogenic beta cell stress, including DNA damage, inflammation, lipotoxicity and endoplasmic reticulum (ER) stress. DNA damage induced apoptosis by treatment with the commonly used diabetogenic agent streptozotocin (STZ) is regulated by both ATM and P53. We show that ATM is a key STZ induced activator of P53 and that amelioration of STZ induced cell death by inhibition of ATM mainly depends on P53. While both P53 and ATM control lipotoxic beta cell apoptosis, ATM but not P53 fails to alter inflammatory beta cell death. In contrast, tunicamycin induced (ER stress associated) apoptosis is further increased by ATM knockdown or inhibition, but not by P53 knockdown. Our results reveal differential roles for P53 and ATM in beta cell survival in vitro in the context of four key pathophysiological types of diabetogenic beta cell stress, and indicate that ATM can use P53 independent signaling pathways to modify beta cell survival, dependent on the cellular insult.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sobrevivência Celular/genética , Células Secretoras de Insulina/patologia , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas Mutadas de Ataxia Telangiectasia/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Diabetes Mellitus/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Técnicas de Silenciamento de Genes , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Ratos , Estreptozocina/toxicidade , Tunicamicina/toxicidade
16.
Ecotoxicol Environ Saf ; 205: 111089, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810645

RESUMO

Early molecular events after the exposure of heavy metals, such as aberrant DNA methylation, suggest that DNA methylation was important in regulating physiological processes for animals and accordingly could be used as environmental biomarkers. In the present study, we found that copper (Cu) exposure increased lipid content and induced the DNA hypermethylation at the whole genome level. Especially, Cu induced hypermethylation of glucose-regulated protein 78 (grp78) and peroxisome proliferator-activated receptor gamma coactivator-1α (pgc1α). CCAAT/enhancer binding protein α (C/EBPα) could bind to the methylated sequence of grp78, whereas C/EBPß could not bind to the methylated sequence of grp78. These synergistically influenced grp78 expression and increased lipogenesis. In contrast, DNA methylation of PGC1α blocked the specific protein 1 (SP1) binding and interfered mitochondrial function. Moreover, Cu increased reactive oxygen species (ROS) production, activated endoplasmic reticulum (ER) stress and damaged mitochondrial function, and accordingly increased lipid deposition. Notably, we found a new toxicological mechanism for Cu-induced lipid deposition at DNA methylation level. The measurement of DNA methylation facilitated the use of these epigenetic biomarkers for the evaluation of environmental risk.


Assuntos
Carpas/fisiologia , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Carpas/metabolismo , Cobre/metabolismo , Estresse do Retículo Endoplasmático , Glucose/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Lipídeos , Metilação , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ativação Transcricional , Regulação para Cima
17.
Nat Commun ; 11(1): 4286, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855403

RESUMO

Intracellular galectins are carbohydrate-binding proteins capable of sensing and repairing damaged lysosomes. As in the physiological conditions glycosylated moieties are mostly in the lysosomal lumen but not cytosol, it is unclear whether galectins reside in lysosomes, bind to glycosylated proteins, and regulate lysosome functions. Here, we show in gut epithelial cells, galectin-9 is enriched in lysosomes and predominantly binds to lysosome-associated membrane protein 2 (Lamp2) in a Asn(N)-glycan dependent manner. At the steady state, galectin-9 binding to glycosylated Asn175 of Lamp2 is essential for functionality of lysosomes and autophagy. Loss of N-glycan-binding capability of galectin-9 causes its complete depletion from lysosomes and defective autophagy, leading to increased endoplasmic reticulum (ER) stress preferentially in autophagy-active Paneth cells and acinar cells. Unresolved ER stress consequently causes cell degeneration or apoptosis that associates with colitis and pancreatic disorders in mice. Therefore, lysosomal galectins maintain homeostatic function of lysosomes to prevent organ pathogenesis.


Assuntos
Galectinas/metabolismo , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Lisossomos/metabolismo , Pâncreas/patologia , Celulas de Paneth/patologia , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Autofagia/fisiologia , Colite/metabolismo , Colite/patologia , Estresse do Retículo Endoplasmático , Galectinas/genética , Células HT29 , Humanos , Proteína 2 de Membrana Associada ao Lisossomo/genética , Lisossomos/genética , Lisossomos/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pâncreas/metabolismo , Pancreatite/metabolismo , Pancreatite/patologia , Celulas de Paneth/metabolismo
18.
PLoS One ; 15(8): e0237015, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760098

RESUMO

Graves' orbitopathy (GO) is characterised in early stages by orbital fibroblast inflammation, which can be aggravated by oxidative stress and often leads to fibrosis. Protein tyrosine protein 1B (PTP1B) is a regulator of inflammation and a therapeutic target in diabetes. We investigated the role of PTP1B in the GO mechanism using orbital fibroblasts from GO and healthy non-GO subjects. After 24 hours of transfection with PTPN1 siRNA, the fibroblasts were exposed to interleukin (IL)-1ß, cigarette smoke extract (CSE), H2O2, and transforming growth factor (TGF)-ß stimulations. Inflammatory cytokines and fibrosis-related proteins were analysed using western blotting and/or enzyme-linked immunosorbent assay (ELISA). Reactive oxygen species (ROS) release was detected using an oxidant-sensitive fluorescent probe. IL-1ß, tumor necrosis factor (TNF)-α, bovine thyroid stimulating hormone (bTSH), high-affinity human stimulatory monoclonal antibody of TSH receptor (M22), and insulin-like growth factor-1 (IGF-1) significantly increased PTP1B protein production in GO and non-GO fibroblasts. PTPN1 silencing significantly blocked IL-1ß-induced inflammatory cytokine production, CSE- and H2O2-induced ROS synthesis, and TGF-ß-induced expression of collagen Iα, α-smooth muscle actin (SMA), and fibronectin in GO fibroblasts. Silencing PTPN1 also decreased phosphorylation levels of Akt, p38, and c-Jun N-terminal kinase (JNK) and endoplasmic reticulum (ER)-stress response proteins in GO cells. PTP1B may be a potential therapeutic target of anti-inflammatory, anti-oxidant and anti-fibrotic treatment of GO.


Assuntos
Oftalmopatia de Graves/enzimologia , Oftalmopatia de Graves/terapia , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Adulto , Animais , Apoptose , Bovinos , Sobrevivência Celular , Citocinas/biossíntese , Estresse do Retículo Endoplasmático , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Inativação Gênica , Oftalmopatia de Graves/patologia , Humanos , Técnicas In Vitro , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/genética , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
19.
Life Sci ; 259: 118180, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758622

RESUMO

AIMS: Bufothionine had been used for gastric cancer (GC) treatment, and this study managed to uncover the underlying mechanisms. MATERIALS AND METHODS: Cell proliferation was determined by CCK-8 assay and colony formation assay. Flow cytometry (FCM) and TUNEL assay were used to measure cell apoptosis ratio. Intracellular ROS was measured by DCFH-DA probes. qRT-PCR was used to determine miRNAs levels. Western Blot was performed to probe proteins. Dual-luciferase reporter gene system was employed to validate the binding sites of miR-133a-3p and 3'UTR regions of IGF1R mRNA. Immunohistochemistry (IHC) was used to determine the expressions of Ki-67 in mice tumor tissues. KEY FINDINGS: Bufothionine inhibited cell viability, triggered ER stress and promoted ROS production in GC cells, and both ER stress inhibitor Salburinal (Sal) and ROS scavenger (NAC) abrogated Bufothionine induced GC cell death. Besides, miR-133a-3p was upregulated by Bufothionine, and Bufothionine-induced cell death was enhanced by miR-133a-3p overexpression while alleviated by miR-133a-3p knockdown. Furthermore, miR-133a-3p inactivated PI3K/Akt signal pathway by sponging IGF1R, and Bufothionine inhibited insulin-like growth factor 1 receptor (IGF1R) and inactivated PI3K/Akt cascade by upregulating miR-133a-3p. Notably, the promoting effects of overexpressed miR-133a-3p on Bufothionine-induced GC cell death were abrogated by overexpressing IGF1R, and aggravated by the PI3K/Akt cascade inhibitor (LY294002). SIGNIFICANCE: Bufothionine promoted GC cell death by triggering miR-133a-3p/IGF1R/PI3K/Akt axis mediated ER stress and ROS production.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Alcaloides Indólicos/farmacologia , MicroRNAs/genética , Compostos de Quinolínio/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Neoplasias Gástricas/patologia , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Proliferação de Células , Cromonas/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/biossíntese , Morfolinas/farmacologia , Proteína Oncogênica v-akt/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptor IGF Tipo 1/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Mutat Res ; 785: 108321, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32800272

RESUMO

BRAF is a member of the RAF family of serine/threonine-specific protein kinases. Oncogenic BRAF, in particular, BRAF V600E, can disturb the normal protein folding machinery in the endoplasmic reticulum (ER) leading to accumulation of unfolded/misfolded proteins in the ER lumen, a condition known as endoplasmic reticulum (ER) stress. To alleviate such conditions, ER-stressed cells have developed a highly robust and adaptable signaling network known as unfolded protein response (UPR). UPR is ordinarily a cytoprotective response and usually operates through the induction of autophagy, an intracellular lysosomal degradation pathway that directs damaged proteins, protein aggregates, and damaged organelles for bulk degradation and recycling. Both ER stress and autophagy are involved in the progression and chemoresistance of melanoma. Melanoma, which arises as a result of malignant transformation of melanocytes, exhibits exceptionally high therapeutic resistance. Many mechanisms of therapeutic resistance have been identified in individual melanoma patients and in preclinical BRAF-driven melanoma models. Recently, it has been recognized that oncogenic BRAF interacts with GRP78 and removes its inhibitory influence on the three fundamental ER stress sensors of UPR, PERK, IRE1α, and ATF6. Dissociation of GRP78 from these ER stress sensors prompts UPR that subsequently activates cytoprotective autophagy. Thus, pharmacological inhibition of BRAF-induced ER stress-mediated autophagy can potentially resensitize BRAF mutant melanoma tumors to apoptosis. However, the underlying molecular mechanism of how oncogenic BRAF elevates the basal level of ER stress-mediated autophagy in melanoma tumors is not well characterized. A better understanding of the crosstalk between oncogenic BRAF, ER stress and autophagy may provide a rationale for improving existing cancer therapies and identify novel targets for therapeutic intervention of melanoma.


Assuntos
Autofagia , Resistencia a Medicamentos Antineoplásicos , Estresse do Retículo Endoplasmático , Melanoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Resposta a Proteínas não Dobradas , Apoptose , Humanos , Melanoma/tratamento farmacológico , Transdução de Sinais , Neoplasias Cutâneas/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA