RESUMO
Resistance to chemotherapy is the deadlock in cancer treatment. In this study, we used wild-type LOVO (LOVOWT ), a human colon cancer cell line, and the oxaliplatin-resistant sub-clone LOVOOR cells to investigate the molecular mechanisms of the development of drug resistance in colon cancer. Compared with LOVOWT cells, LOVOOR cells had a high proliferation capacity and a high percentage on the G2/M phase. The expression and activation of Aurora-A, a critical kinase in G2/M phase, were higher in LOVOOR cells than in LOVOWT cells. The results from immunofluorescence indicated an irregular distribution of Aurora-A in LOVOOR cells. To evaluate the importance of Aurora-A in oxaliplatin-resistant property of LOVOOR cells, overexpression of Aurora-A in LOVOWT cells and otherwise knockdown of Aurora-A in LOVOOR cells were performed and followed by administration of oxaliplatin. The results indicated that Aurora-A might contribute to the resistance of LOVOOR cells to oxaliplatin treatment by depressing p53 signaling. The specific findings in this study provide a possibility that targeting Aurora-A might be a solution for patients who have failed oxaliplatin treatment.
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Antineoplásicos , Neoplasias do Colo , Humanos , Oxaliplatina/farmacologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Resistencia a Medicamentos AntineoplásicosRESUMO
Parkinson's disease (PD) is a common neurodegenerative disorder associated with striatal dopaminergic neuronal loss in the Substantia nigra. Oxidative stress plays a significant role in several neurodegenerative diseases. Paraquat (PQ) is considered a potential neurotoxin that affects the brain leading to the death of dopaminergic neurons mimicking the PD phenotype. Various scientific reports have proven that cryptotanshinone possesses antioxidant and anti-inflammatory properties. We hypothesized that cryptotanshinone could extend its neuroprotective activity by exerting antioxidant effects. This study was designed to evaluate the effects of cryptotanshinone in both cellular and animal models of PQ-induced PD. Annexin V-PI double staining and immunoblotting were used to detect apoptosis and oxidative stress proteins, respectively. Reactive oxygen species kits were used to evaluate oxidative stress in cells. For in vivo studies, 18 B6 mice were divided into three groups. The rotarod data revealed the motor function and immunostaining showed the survival of TH+ neurons in SNpc region. Our study showed that cryptotanshinone attenuated paraquat-induced oxidative stress by upregulating anti-oxidant markers in vitro, and restored behavioral deficits and survival of dopaminergic neurons in vivo, demonstrating its therapeutic potential.
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Fármacos Neuroprotetores , Doença de Parkinson , Animais , Camundongos , Paraquat/toxicidade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Neurônios Dopaminérgicos/metabolismo , Estresse Oxidativo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Modelos Animais de DoençasRESUMO
The heart is a very dynamic pumping organ working perpetually to maintain a constant blood supply to the whole body to transport oxygen and nutrients. Unfortunately, it is also subjected to various stresses based on physiological or pathological conditions, particularly more vulnerable to damages caused by oxidative stress. In this study, we investigate the molecular mechanism and contribution of IGF-IIRα in endoplasmic reticulum stress induction in the heart under doxorubicin-induced cardiotoxicity. Using in vitro H9c2 cells, in vivo transgenic rat cardiac tissues, siRNAs against CHOP, chemical ER chaperone PBA, and western blot experiments, we found that IGF-IIRα overexpression enhanced ER stress markers ATF4, ATF6, IRE1α, and PERK which were further aggravated by DOX treatment. This was accompanied by a significant perturbation in stress-associated MAPKs such as p38 and JNK. Interestingly, PARKIN, a stress responsive cellular protective mediator was significantly downregulated by IGF-IIRα concomitant with decreased expression of ER chaperone GRP78. Furthermore, ER stress-associated pro-apoptotic factor CHOP was increased considerably in a dose-dependent manner followed by elevated c-caspase-12 and c-caspase-3 activities. Conversely, treatment of H9c2 cells with chemical ER chaperone PBA or siRNA against CHOP abolished the IGF-IIRα-induced ER stress responses. Altogether, these findings suggested that IGF-IIRα contributes to ER stress induction and inhibits cellular stress coping proteins while increasing pro-apoptotic factors feeding into a cardio myocyte damage program that eventually paves the way to heart failure.
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Estresse do Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Miocárdio/metabolismo , Receptor IGF Tipo 2/metabolismo , Animais , Linhagem Celular , Citotoxinas/efeitos adversos , Citotoxinas/farmacologia , Doxorrubicina/efeitos adversos , Doxorrubicina/farmacologia , Retículo Endoplasmático/genética , Ratos , Ratos Transgênicos , Receptor IGF Tipo 2/genéticaRESUMO
Hepatocellular carcinoma is a common type of liver cancer. Resistance to chemotherapeutic agents is a major problem in cancer therapy. MicroRNAs have been reported in cancer development and tumor growth; however, the relationship between chemoresistance and hepatocellular carcinoma needs to be fully investigated. Here, we treated hepatocellular carcinoma cell line (HA22T) with a histone deacetylase inhibitor to establish hepatocellular carcinoma-resistant cells (HDACi-R) and investigated the molecular mechanisms of chemoresistance in HCC cells. Although histone deacetylase inhibitor could not enhance cell death in HDACi-R but upregulation of miR-107 decreased cell viability both in parental cells and resistance cells, decreased the expression of cofilin-1, enhanced ROS-induced cell apoptosis, and dose-dependently sensitized HDACi-R to HDACi. Further, miR-107 upregulation resulted in tumor cell disorganization in both HA22T and HDACi-R in a mice xenograft model. Our findings demonstrated that miR-107 downregulation leads to hepatocellular carcinoma cell resistance in HDACi via a cofilin-1-dependent molecular mechanism and ROS accumulation.
Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Inibidores de Histona Desacetilases/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Cofilina 1/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Inibidores de Histona Desacetilases/uso terapêutico , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , MicroRNAs/agonistas , MicroRNAs/genética , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Pathological cardiac hypertrophy is associated with many diseases including hypertension. Recent studies have identified important roles for microRNAs (miRNAs) in many cardiac pathophysiological processes, including the regulation of cardiomyocyte hypertrophy. However, the role of miR-145-5p in the cardiac setting is still unclear. In this study, H9C2 cells were overexpressed with microRNA-145-5p, and then treated with Ang-II for 24 h, to study the effect of miR-145-5p on Ang-II-induced myocardial hypertrophy in vitro. Results showed that Ang-II treatment down-regulated miR-145-5p expression were revered after miR-145-5p overexpression. Based on results of bioinformatics algorithms, paxillin was predicted as a candidate target gene of miR-145-5p, luciferase activity assay revealed that the luciferase activity of cells was substantial downregulated the following co-transfection with wild paxillin 3'UTR and miR-145-5p compared to that in scramble control, while the inhibitory effect of miR-145-5p was abolished after transfection of mutant paxillin 3'UTR. Additionally, overexpression of miR-145-5p markedly inhibited activation of Rac-1/ JNK /c-jun/ NFATc3 and ANP expression and induced SIRT1 expression in Ang-II treated H9c2 cells. Jointly, our study suggested that miR-145-5p inhibited cardiac hypertrophy by targeting paxillin and through modulating Rac-1/ JNK /c-jun/ NFATc3/ ANP / Sirt1 signaling, therefore proving novel downstream molecular pathway of miR-145-5p in cardiac hypertrophy.
Assuntos
Angiotensina II/toxicidade , Cardiomegalia/tratamento farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , MicroRNAs/genética , Mioblastos Cardíacos/efeitos dos fármacos , Paxilina/antagonistas & inibidores , Animais , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Células Cultivadas , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Mioblastos Cardíacos/metabolismo , Mioblastos Cardíacos/patologia , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Ratos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Vasoconstritores/toxicidade , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismoRESUMO
Obesity in aged population have surges the occurrence of various metabolic disorders including Nonalcoholic fatty liver disease (NAFLD). Apoptosis in the liver is one of the causative factors for NAFLD-induced liver damage. Plants derived bioactive peptides have been shown as an alternative treatment approach for the treating NAFLD due to its less toxicity. Moderate exercise has been reported to improve cellular physiological function prevent age associated metabolic disorders. In the present study, we evaluate the effects of bioactive dipeptide (IF) derived from alcalase potato-protein hydrolysates and swimming exercise in preventing High Fat Diet (HFD)-induced liver damage in senescence accelerated mouse-prone 8 (SAMP8) mice model. Mouse were fed with HFD for 6 weeks followed by oral IF administration or swimming exercise and both for 8 weeks. HFD induces significant structural changes in liver of HFD fed SAMP8 mouse. Both IF administration and exercise prevent the structural abnormalities induced by HFD, however, combined IF treatment and exercise offer better protection. Combined IF treatment and exercise activate PI3K/Akt cell survival protein and effectively inhibit Fas-FADD-induced apoptosis in HFD fed aged mouse. Oral supplementation of bioactive peptide IF combined with moderate swimming exercise effectively alleviate HFD-induced hepatic injury in aged mice.
Assuntos
Apoptose , Dipeptídeos/farmacologia , Hepatócitos/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Condicionamento Físico Animal , Hidrolisados de Proteína/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Natação , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dieta Hiperlipídica , Hepatócitos/efeitos dos fármacos , Camundongos , Solanum tuberosum/químicaRESUMO
High-glucose (HG) suppresses mesenchymal stem cell (MSC) functions, resulting in a decrease in cardiac regenerative capability for MSC in diabetes mellitus (DM). Resveratrol enhances MSC functions under stress. This study explores if cardiac regenerative capability can be enhanced in MSCs pretreated with resveratrol in DM rats receiving MSCs. In vitro evidence confirms that HG decreases MSCs capability through suppression of survival markers, AMP-activated protein kinase (AMPK)/Sirtuin 1 (Sirt1) axis, and expression of apoptotic markers. All of these markers are improved when MSCs are cocultured with resveratrol. Wistar male rats were randomly divided into Sham, DM (DM rats), DM rats with autologous transplantation of adipose-derived stem cells (DM + ADSC), and DM rats with resveratrol pretreated ADSC (DM + RSVL-ADSC). Compared to the Sham, DM induces pathological pathways (including fibrosis, hypertrophy, and apoptosis) and suppresses survival as well as the AMPK/Sirt1 axis in the DM group. DM + ADSC slightly improves the above pathways whereas DM + RSVL-ADSC significantly improves the above pathways when compared to the DM group. These results illustrate that resveratrol pretreated with MSCs may show clinical potential in the treatment of heart failure in patients with DM.
Assuntos
Antioxidantes/farmacologia , Cardiomiopatias Diabéticas/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regeneração , Resveratrol/farmacologia , Sirtuína 1/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Tecido Adiposo/citologia , Animais , Comunicação Celular , Linhagem Celular , Proliferação de Células , Técnicas de Cocultura , Cardiomiopatias Diabéticas/enzimologia , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/fisiopatologia , Modelos Animais de Doenças , Masculino , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/patologia , Ratos Wistar , Transdução de Sinais , Função Ventricular EsquerdaRESUMO
It has been increasingly recognized that accelerated atherosclerosis is a major cause of morbidity and mortality in patients with systemic lupus erythematosus, a multisystem autoimmune disease. In this study, we investigated the anti-apoptotic effects of heat-killed Lactobacillus reuteri GMNL-263 on the cardiac tissue of NZB/W F1 mice. The myocardial architecture of the mice heart was observed and evaluated using different staining techniques such as hematoxylin and eosin, TUNEL assay, Masson's trichrome, and fluorescent immunohistochemistry. Additionally, the probiotics-related pathway proteins were analyzed via western blot analysis. Our results showed prevention of enlarged interstitial spaces and abnormal myocardial structures in the hearts of NZB/W F1 mice with L. reuteri GMNL-263 feeding. Significant reduction in TUNEL-positive cells, Fas death receptor-related components, and apoptosis was also detected in the cardiac tissues of the NZB/W F1 mice after L. reuteri GMNL-263 feeding compared with the control group. These findings are the first to reveal the protective effects of L. reuteri GMNL-263 against cardiac abnormalities in NZB/W F1 mice and suggest the potential clinical applications of L. reuteri GMNL-263 in the treatment of SLE-related cardiovascular diseases.
Assuntos
Cardiomiopatias , Temperatura Alta , Limosilactobacillus reuteri , Lúpus Eritematoso Sistêmico , Probióticos/farmacologia , Animais , Cardiomiopatias/etiologia , Cardiomiopatias/prevenção & controle , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/terapia , CamundongosRESUMO
It has been reported that two sets of blot figures in Figure 3A,C looked identical in the original published paper [...].
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Pancreatic damage is the major causative agent in type 1 diabetes mellitus (DM). Several strategies have been suggested to regenerate pancreatic functions, such as stem cell transplantation and administration of active components isolating from natural herbals. This study aims to investigate if the synergistically protective effect on damaged pancreatic tissues can be observed in STZ-induced DM rats with autologous transplantation of adipose-derived stem cells (ADSC) coupling with oral administration of resveratrol. Pathological conditions can be recognized in DM rats with pancreatic damage, including reduction of islet size, suppression of survival markers, downregulation of AMPK/Sirt1 axis, and activation of apoptotic signaling. Autologous transplantation of ADSC slightly improves pancreatic functions, whereas autologous transplantation of ADSC coupling with oral administration of resveratrol significantly improves pancreatic functions in DM rats. We suggest that oral administration of resveratrol may enhance the therapeutic effect on DM patients receiving autologous transplantation of ADSC.
Assuntos
Diabetes Mellitus , Tecido Adiposo , Animais , Pâncreas , Ratos , Regeneração , Resveratrol , Transplante AutólogoRESUMO
Although various advancements in radical surgery and neoadjuvant chemotherapy have been developed in treating osteosarcoma (OS), their clinical prognosis remains poor. A synthetic chemical compound, 3-hydroxylflavone, that is reported to regulate ROS production is known to inhibit human bone osteosarcoma cells. However, its role and mechanism in human OS cells remains unclear. In this study, we have determined the potential of 3-Hydroxy-2-phenylchromone (3-HF) against OS using human osteosarcoma (HOS) cells. Our previous studies showed that Zipper sterile-alpha-motif kinase (ZAK), a kinase member of the MAP3K family, was involved in various cellular events such as cell proliferation and cell apoptosis, and encoded two transcriptional variants, ZAKα and ß. In this study, we show that 3-HF induces the expression of ZAK and thereby enhances cellular apoptosis. Using gain of function and loss of function studies, we have demonstrated that ZAK activation by 3-HF in OS cells is confined to a ZAKß form that presumably plays a leading role in triggering ZAKα expression, resulting in an aggravated cancer apoptosis. Our results also validate ZAKß as the predominant form of ZAK to drive the anticancer mechanism in HOS cells.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/patologia , Flavonoides/farmacologia , MAP Quinase Quinase 4/efeitos dos fármacos , MAP Quinase Quinase Quinases/efeitos dos fármacos , Osteossarcoma/patologia , Caspase 3/biossíntese , Caspase 3/genética , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Mutação com Ganho de Função , Humanos , Mutação com Perda de Função , MAP Quinase Quinase Quinases/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Isoformas de Proteínas/efeitos dos fármacos , Isoformas de Proteínas/genética , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Guanine nucleotide-binding protein-like-3-like (GNL3L) is a crucial regulator of NF-κB signaling that is aberrantly activated during diverse chemoresistance-associated cellular processes. However, the molecular mechanisms of GNL3L tumor initiation and resistant state are largely unknown. Moreover, the identification of predictive biomarkers is necessary to effectively generate therapeutic strategies for metastatic human colorectal cancer (CRC). This study aims to identify how cells acquire resistance to anticancer drugs and whether the downregulation of miR-4454 is associated with the progression of CRC. Here, we have shown that the overexpression of miR-4454 in resistant tumors is a crucial precursor for the posttranscriptional repression of GNL3L in human chemoresistant CRC progression, and we used doxycycline induced miR-4454 overexpression that significantly reduced tumor volume in a subcutaneous injection nude mice model. Together, these observations highlight that the downregulation of miR-4454 in resistant clones is prominently responsible for maintaining their resistance against anticancer drug therapy. Our study indicates that the development of miR-4454 as a microRNA-based therapeutic approach to silence GNL3L may remarkably reduce oncogenic cell survival that depends on GNL3L/NF-κB signaling, making miR-4454 a candidate for treating metastatic human CRC.
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In this study, we used ICI 182 780 (ICI), an estrogen receptor (ER) antagonist, to investigate the estrogenic activity of Danshen, and to further explored whether Danshen extract can block Leu27IGF-II-induced hypertrophy in H9c2 cardiomyoblast cells. We first used an IGF-II analog Leu27IGF-II, which specifically activates IGF2R signaling cascades and induces H9c2 cardiomyoblast cell hypertrophy. However, Danshen extract completely inhibited Leu27IGF-II-induced cell size increase, ANP and BNP hypertrophic marker expression, and IGF2R induction. We also observed that Danshen extract inhibited calcineurin protein expression and NFAT3 nuclear translocation, leading to suppression of Leu27IGF-II-induced cardiac hypertrophy. Moreover, the anti-Leu27IGF-II-IGF2R signaling effect of Danshen was totally reversed by ICI, which suggest the cardio protective effect of Danshen is mediated through estrogen receptors. Our study suggests that, Danshen exerts estrogenic activity, and thus, it could be used as a selective ER modulator in IGFIIR induced hypertrophy model.
Assuntos
Crescimento Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Fator de Crescimento Insulin-Like II/análogos & derivados , Mioblastos Cardíacos/efeitos dos fármacos , Receptor IGF Tipo 2/metabolismo , Salvia miltiorrhiza/química , Animais , Calcineurina/metabolismo , Cardiomegalia/prevenção & controle , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/isolamento & purificação , Antagonistas do Receptor de Estrogênio/farmacologia , Fulvestranto/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Mioblastos Cardíacos/metabolismo , Mioblastos Cardíacos/patologia , Transporte Proteico , Ratos , Receptores de Estrogênio/metabolismo , Transdução de SinaisRESUMO
The use of herbs as alternative cardiovascular disease treatment has attracted a great deal of attention owing to their lower toxicity. Whether Carthamus tinctorius extract prevent cardiomyoblast cell hypertrophy remains unclear. The present study was performed to investigate the effect of C tinctorius extract (CTF) on rat cardiomyoblast cell H9c2 and the possible molecular mechanisms. H9c2 cells were treated with lipopolysaccharide (LPS; 2 µg/mL) for 12 hours, subsequently treated with CTF (1-25 µg/mL) The incubation continued for another 24 hours, and the cells were analyzed with actin staining assay, western blot analysis, and siRNA transfection assays. In the present study, the increased cell size induced by LPS was significantly decreased by pretreating at a concentration of 1-25 µg/mL CTF. It was found that CTF could inhibit cardiac hypertrophy induced by LPS and decrease hypertrophic proteins calcineurin, p-GATA-4, GATA-4, atrial natriuretic peptide, and B-type natriuretic peptide levels in H9c2 cells. Additionally, LPS-induced insulin-like growth factor-II receptor (IGF-IIR) hypertrophy pathway was downregulated by CTF. Moreover, IGF-IR siRNA or inhibitors both reversed the CTF effects, confirming that CTF activates IGF-1R to prevent LPS-induced H9c2 cardiomyoblast cell hypertrophy. The current findings indicate that CTF activates IGF-IR to inhibit IGF-IIR signaling pathway which resulted in reducing H9c2 cardiomyoblast cell hypertrophy induced by LPS.
Assuntos
Carthamus tinctorius/química , Lipopolissacarídeos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Receptor IGF Tipo 1/metabolismo , Receptor IGF Tipo 2/metabolismo , Animais , Cardiomegalia/prevenção & controle , Tamanho Celular , Relação Dose-Resposta a Droga , Técnicas de Silenciamento de Genes , Miócitos Cardíacos/metabolismo , Extratos Vegetais/isolamento & purificação , Ratos , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 2/genética , Transdução de SinaisRESUMO
Cardiac hypertrophy is a common phenomenon observed in progressive heart disease associated with heart failure. Insulin-like growth factor receptor II (IGF-IIR) has been much implicated in myocardial hypertrophy. Our previous studies have found that increased activities of signaling mediators, such as calcium/calmodulin-dependent protein kinase II (CaMKII) and calcineurin induces pathological hypertrophy. Given the critical roles played by CaMKII and calcineurin signaling in the progression of maladaptive hypertrophy, we anticipated that inhibition of CaMKII and calcineurin signaling may attenuate IGF-IIR-induced cardiac hypertrophy. The current study, therefore, investigated the effects of IGF-IIR activation on the CaMKII and calcineurin signaling and whether the combinatorial inhibition of the CaMKIIδ and calcineurin signaling could ameliorate IGF-IIR-induced pathological hypertrophy. In the present study, we induced IGF-IIR through the cardiomyocyte-specific transduction of IGFIIY27L via adeno-associated virus 2 (AAV2) to evaluate its effects on cardiac hypertrophy. Interestingly, it was observed that the activation of IGF-IIR signaling through IGFIIY27L induces significant hypertrophy of the myocardium and increased cardiac apoptosis and fibrosis. Moreover, we found that Leu27 IGF-II significantly induced calcineurin and CaMKII expression. Furthermore and importantly, the combinatorial treatment with CaMKII and calcineurin inhibitors significantly alleviates IGF-IIR-induced hypertrophic responses. Thus, it could be envisaged that the inhibition of IGF-IIR may serve as a promising candidate for attenuating maladaptive hypertrophy. Both calcineurin and CaMKII could be valuable targets for developing treatment strategies against hypertension-induced cardiomyopathies.
Assuntos
Calcineurina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Cardiomegalia/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Receptor IGF Tipo 2/genética , Animais , Apoptose/genética , Calcineurina/efeitos dos fármacos , Inibidores de Calcineurina/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/antagonistas & inibidores , Cardiomegalia/genética , Cardiomegalia/patologia , Modelos Animais de Doenças , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/genética , Hipertensão/patologia , Fator de Crescimento Insulin-Like II/genética , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Ratos , Transdução de Sinais/efeitos dos fármacosRESUMO
Hepatocellular carcinoma (HCC) is a common fatal type of malignant tumor that has highly metastatic and recurrent properties. Fisetin is a natural flavonoid found in various vegetables and fruits which exhibits anti-cancer and anti-inflammatory properties, as well as other effects. Thus, we hypothesized that fisetin can act as an adjuvant therapy in cancer or drug-resistant cancer cells, and further investigated the molecular mechanisms underlying the development of drug-resistance in HCC cells. We found that fisetin effectively inhibited the cell viability of not only parental cells but also histone deacetylase inhibitors-resistant (HDACis-R) cells and enhanced the chemosensitivity of HCC cells. Interestingly, fisetin did not induce cell apoptosis through the activation of the endoplasmic reticulum (ER) stress sensor of protein kinase R (PKR)-like endoplasmic reticulum kinase, but rather through the non-canonical pathway of the protein phosphatase 1 (PP1)-mediated suppression of eIF2α phosphorylation. Moreover, fisetin-induced cell apoptosis was reversed by treatment with PP1 activator or eIF2α siRNA in HCC cells. Based on these observations, we suggest that PP1-eIF2α pathways are significantly involved in the effect of fisetin on HCC apoptosis. Thus, fisetin may act as a novel anticancer drug and new chemotherapy adjuvant which can improve the efficacy of chemotherapeutic agents and diminish their side-effects.
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Previous studies stated that stem cell functions are reduced under high glucose environment, leading to reduce stem cell capability of tissue regeneration. This study aimed to investigate if stem cells preconditioned with resveratrol show better therapeutic effect on the treatment of liver dysfunction in diabetic rats than stem cells without resveratrol precondition. Male Wistar rats were divided into four groups including sham, DM (diabetic rats), DM + ADSC (DM rats receiving autologous transplantation of adipose-derived stem cells), and DM + pre-R-ADSC (DM rats receiving ADSC preconditioned with resveratrol). Compared with sham group, experimental results showed that DM group induced suppression of survival, suppression of Sirt1, activation of apoptotic, and activation of fibrotic pathways, leading to liver dysfunction. Autologous transplantation of ADSC (DM + ADSC) improved above pathways except for fibrotic signaling. By contrast, transplantation of resveratrol preconditioned ADSC (DM + pre-R-ADSC) significantly improved above pathways including fibrosis. Supplemental evidences suggest that resveratrol precondition increases ADSC viability under high glucose stress via Sirt1 and IGF1R expressions. Furthermore, increased secretion of IGF1 via paracrine route also confirmed in ADSC preconditioned with resveratrol. The experimental results imply that ADSC preconditioned with resveratrol shows potential in the treatment of liver dysfunction in DM patients with liver dysfunction.
Assuntos
Tecido Adiposo/citologia , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Experimental/terapia , Hepatopatias/terapia , Substâncias Protetoras/uso terapêutico , Resveratrol/uso terapêutico , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Apoptose , Sobrevivência Celular/efeitos dos fármacos , Células Clonais , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Glucose/toxicidade , Fígado/efeitos dos fármacos , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Ratos Wistar , Resveratrol/farmacologia , Transdução de Sinais , Sirtuína 1/metabolismo , Sobrevivência de Tecidos/efeitos dos fármacos , Transplante AutólogoRESUMO
Doxorubicin (DOX) is an anthracycline antibiotic commonly employed for the treatment of various cancers. However, its therapeutic uses are hampered by side effects associated with cumulative doses during the course of treatment. Whereas deregulation of autophagy in the myocardium has been involved in a variety of cardiovascular diseases, the role of autophagy in DOX-induced cardiomyopathy remains debated. Our earlier studies have shown that DOX treatment in a rat animal model leads to increased expression of the novel stress-inducible protein insulin-like growth factor II receptor-α (IGF-IIRα) in cardiac tissues, which exacerbated the cardiac injury by enhancing oxidative stress and p53-mediated mitochondria-dependent cardiac apoptosis. Through this study, we investigated the contribution of IGF-IIRα to dysregulation of autophagy in heart using both in vitro H9c2 cells (DOX treated, 1 µM) and in vivo transgenic rat models (DOX treated, 5 mg/kg ip for 6 wk) overexpressing IGF-IIRα specifically in the heart. We found that IGF-IIRα primarily localized to mitochondria, causing increased mitochondrial oxidative stress that was severely aggravated by DOX treatment. This was accompanied by a significant perturbation in mitochondrial membrane potential and increased leakage of cytochrome c, causing increased cleaved caspase-3 activity. There were significant alterations in phosphorylated AMP-activated protein kinase (p-AMPK), phosphorylated Unc-51 like kinase-1 (p-ULK1), PARKIN, PTEN-induced kinase 1 (PINK1), microtubule-associated protein 1 light chain 3 (LC3), and p62 proteins, which were more severely disrupted under the combined effect of IGF-IIRα overexpression plus DOX. Finally, LysoTracker Red staining showed that IGF-IIRα overexpression causes lysosomal impairment, which was rescued by rapamycin treatment. Taken together, we found that IGF-IIRα leads to mitochondrial oxidative stress, decreased antioxidant levels, disrupted mitochondrial membrane potential, and perturbed mitochondrial autophagy contributing to DOX-induced cardiomyopathy.
Assuntos
Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Cardiopatias/induzido quimicamente , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Receptor IGF Tipo 2/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Relacionadas à Autofagia/metabolismo , Cardiotoxicidade , Linhagem Celular , Cardiopatias/genética , Cardiopatias/metabolismo , Cardiopatias/patologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Ratos Transgênicos , Receptor IGF Tipo 2/genética , Transdução de Sinais/efeitos dos fármacosRESUMO
Cardiotoxicity by doxorubicin hampers its therapeutic potential as an anticancer drug, but mechanisms leading to cardiotoxicity remain contentious. Through this study, the functional contribution of insulin-like growth factor receptor type II α (IGF-IIRα) which is a novel stress-inducible protein was explored in doxorubicin-induced cardiac stress. Employing both in vitro H9c2 cells and in vivo transgenic rat models (SD-TG [IGF-IIRα]) overexpressing IGF-IIRα specifically in heart, we found that IGF-IIRα leads to cardiac structural abnormalities and functional perturbations that were severely aggravated by doxorubicin-induced cardiac stress. Overexpression of IGF-IIRα leads to cumulative elevation of stress associated cardiac hypertrophy and apoptosis factors. There was a significant reduction of survival associated proteins p-Akt and estrogen receptor ß/α, and abnormal elevation of cardiac hypertrophy markers such as atrial natriuretic peptide, cardiac troponin-I, and apoptosis-inducing agents such as p53, Bax, and cytochrome C, respectively. IGF-IIRα also altered the expressions of AT1R, ERK1/2, and p38 proteins. Besides, IGF-IIRα also increased the reactive oxygen species production in H9c2 cells which were markedly aggravated by doxorubicin treatment. Together, we showed that IGF-IIRα is a novel stress-induced protein that perturbed cardiac homeostasis and cumulatively exacerbated the doxorubicin-induced cardiac injury that perturbed heart functions and ensuing cardiomyopathy.
Assuntos
Antibióticos Antineoplásicos/toxicidade , Cardiomegalia/induzido quimicamente , Cardiomiopatias/induzido quimicamente , Doxorrubicina/toxicidade , Cardiopatias Congênitas/induzido quimicamente , Receptor IGF Tipo 2/biossíntese , Animais , Apoptose/efeitos dos fármacos , Cardiotoxicidade/patologia , Linhagem Celular , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Coração/anatomia & histologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Transgênicos , Espécies Reativas de Oxigênio/metabolismo , Receptor IGF Tipo 2/genética , Transdução de Sinais/efeitos dos fármacosRESUMO
Consumption of high fat diet (HFD) is associated with increased cardiovascular risk factors among elderly people. Aging and obesity induced-cardiac remodeling includes hypertrophy and fibrosis. Gelsolin (GSN) induces cardiac hypertrophy and TGF-ß, a key cytokine, which induces fibrosis. The relationship between TGF-ß and GSN in aging induced cardiac remodeling is still unknown. We evaluated the expressions of TGF-ß and GSN in HFD fed 22 months old aging SD rats, followed by the administration of either probucol or alcalase potato protein hydrolysate (APPH). Western blotting and Masson trichrome staining showed that APPH (45 and 75 mg/kg/day) and probucol (500 mg/kg/day) treatments significantly reduced the aging and HFD-induced hypertrophy and fibrosis. Echocardiograph showed that the performance of the hearts was improved in APPH, and probucol treated HFD aging rats. Serum from all rats was collected and H9c2 cells were cultured with collected serums separately. The GSN dependent hypertrophy was inhibited with an exogenous TGF-ß in H9c2 cells cultured in HFD+ APPH treated serum. Thus, we propose that along with its role in cardiac fibrosis, TGF-ß also acts as an upstream activator of GSN dependent hypertrophy. Hence, TGF-ß in serum could be a promising therapeutic target for cardiac remodeling in aging and/or obese subjects.