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1.
J Adv Res ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38527587

RESUMO

INTRODUCTION: With age and ATP decrease in the body, the transcription factors hypophosphorylation weakens the transcription of Slc40a1 and hinders the expression of the iron discharger ferroportin. This may lead to iron accumulation in the brain and the catalysis of free radicals that damage cerebral neurons and eventually lead to Alzheimer's disease (AD). OBJECTIVES: To prevent AD caused by brain iron excretion disorders and reveal the mechanism of J bs-5YP peptide restoring ferroportin. METHODS: We prepared J bs-YP peptide and administered it to the senile mice with dementia. Then, the intelligence of the mice was tested using a Morris Water Maze. The ATP content in the body was detected using the ATP hydrophysis and Phosphate precipitation method. The activation of Slc40a1 transcription was assayed with ATAC seq and the ferroportin, as well as the phosphorylation levels of Ets1 in brain were detected by Western Blot. RESULTS: The phosphorylation level of Ets1in brain was enhanced, and subsequently, the transcription of Slc40a1 was activated and ferroportin was increased in the brain, the levels of iron and free radicals were reduced, with the neurons protection, and the dementia was ultimately alleviated in the senile mice. CONCLUSION: J bs-5YP can recover the expression of ferroportin to excrete excessive iron in the brain of senile mice with dementia by enhancing the transcription of Slc40a1 via phosphorylating Ets1, revealing the potential of J bs-5YP as a drug to alleviate senile dementia.

2.
Cell Death Discov ; 10(1): 46, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267416

RESUMO

Acute myeloid leukemia (AML), a prevalent form of leukemia in adults, is often characterized by low response rates to chemotherapy, high recurrence rates, and unfavorable prognosis. A critical barrier in managing refractory or recurrent AML is the resistance to chemotherapy. Increasing evidence indicates that tumor cell metabolism plays a crucial role in AML progression, survival, metastasis, and treatment resistance. Autophagy, an essential regulator of cellular energy metabolism, is increasingly recognized for its role in the metabolic reprogramming of AML. Autophagy sustains leukemia cells during chemotherapy by not only providing energy but also facilitating rapid proliferation through the supply of essential components such as amino acids and nucleotides. Conversely, the metabolic state of AML cells can influence the activity of autophagy. Their mutual coordination helps maintain intrinsic cellular homeostasis, which is a significant contributor to chemotherapy resistance in leukemia cells. This review explores the recent advancements in understanding the interaction between autophagy and metabolism in AML cells, emphasizing their roles in cell survival and drug resistance. A comprehensive understanding of the interplay between autophagy and leukemia cell metabolism can shed light on leukemia cell survival strategies, particularly under adverse conditions such as chemotherapy. This insight may also pave the way for innovative targeted treatment strategies.

3.
Cell Death Discov ; 9(1): 208, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37391442

RESUMO

The internal tandem duplication of the juxtamembrane domain of the FMS-like tyrosine kinase 3 (FLT3-ITD) is the most common genetic change in acute myeloid leukemia (AML), and about 30% of all AMLs harbor a FLT3-ITD mutation. Even though FLT3 inhibitors have displayed encouraging effects in FLT3-ITD-mutated AML, the extent of the clinical response to these compounds is cut short due to the rapid development of drug resistance. Evidence has shown that FLT3-ITD triggered activation of oxidative stress signaling may exert a pivotal role in drug resistance. The downstream pathways of FLT3-ITD, including STAT5, PI3K/AKT, and RAS/MAPK, are considered to be major oxidative stress signaling pathways. These downstream pathways can inhibit apoptosis and promote proliferation and survival by regulating apoptosis-related genes and promoting the generation of reactive oxygen species (ROS) through NADPH oxidase (NOX) or other mechanisms. Appropriate levels of ROS may promote proliferation, but high levels of ROS can lead to oxidative damage to the DNA and increase genomic instability. In addition, post-translational modifications of FLT3-ITD and changes in its subcellular localization can affect downstream signaling which may also be one of the mechanisms leading to drug resistance. In this review, we summarized the research progress on NOX mediated oxidative stress signaling and its relationship with drug resistance in FLT3-ITD AML, and discuss the possible new targets in FLT3-ITD signal blocking to reverse drug resistance in FLT3-ITD-mutated AML.

4.
World J Clin Cases ; 11(2): 268-291, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36686358

RESUMO

As an important treatment for acute myeloid leukemia, allogeneic hematopoietic stem cell transplantation (allo-HSCT) plays an important role in reducing relapse and improving long-term survival. With rapid advancements in basic research in molecular biology and immunology and with deepening understanding of the biological characteristics of hematopoietic stem cells, allo-HSCT has been widely applied in clinical practice. During allo-HSCT, preconditioning, the donor, and the source of stem cells can be tailored to the patient's conditions, greatly broadening the indications for HSCT, with clear survival benefits. However, the risks associated with allo-HSCT remain high, i.e. hematopoietic reconstitution failure, delayed immune reconstitution, graft-versus-host disease, and post-transplant relapse, which are bottlenecks for further improvements in allo-HSCT efficacy and have become hot topics in the field of HSCT. Other bottlenecks recognized in the current treatment of individuals diagnosed with acute myeloid leukemia and subjected to allo-HSCT include the selection of the most appropriate conditioning regimen and post-transplantation management. In this paper, we reviewed the progress of relevant research regarding these aspects.

5.
Ann Transl Med ; 10(19): 1049, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36330413

RESUMO

Background: Alzheimer's disease (AD) is the most common cause of dementia. Effective therapy, early diagnosis, and intervention are still lacking. Non-drug therapy and lifestyle interventions have become important means to prevent the occurrence and progression of AD, with nutritional therapy being one such example. Nutritional therapy, as a non-pharmacological intervention for AD, has made significant progress and shown significant promise for the development of treatment regimens in recent years. Niacin is a critical vitamin available in the forms of nicotinamide (NAM) and nicotinic acid (NA). In tissues, niacin is transformed into nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which are involved in a variety of cellular processes. Recent researches indicate that niacin may be beneficial in the prevention and treatment of aging, cancer, and metabolic illnesses. Methods: To detect the mechanism of affection of niacin in AD, we found out GSE135999 from the Gene Expression Omnibus (GEO) database which is microarray data containing samples of 24 wild-type (WT) and 24 APP/PS1 AD mice, given either nicotinamide riboside (NR; 12 mM) or nothing (CTR) in their drinking water. We conducted a more reliable data analysis method Weighted Gene Co-expression Network Analysis (WGCNA) to confirm the central players (hub genes) and related pathways associated between niacin and AD. To validate the affection of niacin in AD mice, we selected 6 WT and 12 APP/PS1 transgenic mice, the 12 APP/PS1 mice were treated with a niacin acid supplement diet or normal food. Six months later, behavioral tests were performed. Results: Our research revealed the hub genes and pathways involved in the enhancement of cognition in AD animal models with niacin supplementation, through transcriptomics analysis, systems biology technique and in vivo. The hub genes were Ctnnb1, Mdm2, Crebbp, Gnb2l1/RACK1 and Pten. The related pathways were circadian rhythm, ubiquitin-mediated proteolysis, and long-term potentiation. Conclusions: A niacin supplementary diet may be a safe and simple choice for AD prevention and treatment. Niacin can enhance cognitive capacity in AD through a variety of mechanisms, among which Ctnnb1, Mdm2, Crebbp, Gnb2l1/RACK1 and Pten are significant.

6.
Cell Death Discov ; 8(1): 397, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36163119

RESUMO

Acute myeloid leukemia (AML) is a hematological malignancy characterized by cytogenetic and genomic alterations. Up to now, combination chemotherapy remains the standard treatment for leukemia. However, many individuals diagnosed with AML develop chemotherapeutic resistance and relapse. Recently, it has been pointed out that leukemic stem cells (LSCs) are the fundamental cause of drug resistance and AML relapse. LSCs only account for a small subpopulation of all leukemic cells, but possess stem cell properties, including a self-renewal capacity and a multi-directional differentiation potential. LSCs reside in a mostly quiescent state and are insensitive to chemotherapeutic agents. When LSCs reside in a bone marrow microenvironment (BMM) favorable to their survival, they engage into a steady, continuous clonal evolution to better adapt to the action of chemotherapy. Most chemotherapeutic drugs can only eliminate LSC-derived clones, reducing the number of leukemic cells in the BM to a normal range in order to achieve complete remission (CR). LSCs hidden in the BM niche can hardly be targeted or eradicated, leading to drug resistance and AML relapse. Understanding the relationship between LSCs, the BMM, and the generation and evolution laws of LSCs can facilitate the development of effective therapeutic targets and increase the efficiency of LSCs elimination in AML.

7.
Free Radic Biol Med ; 190: 216-225, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35970250

RESUMO

Iron accumulates in the brain with age and catalyzes free radical damage to neurons, thus playing a pathogenic role in Alzheimer's disease (AD). To decrease the incidence of AD, we synthesized the iron-affinitive peptide 5YHEDA to scavenge the excess iron in the senile brain. However, the blood-brain barrier (BBB) blocks the entrance of macromolecules into the brain, thus decreasing the therapeutic effects. To facilitate the entrance of the 5YHEDA peptide, we linked the low-density lipoprotein receptor (LDLR)-binding segment of ApoB-100 to 5YHEDA (named "bs-YHEDA"). The results of intravenous injections of bs-5YHEDA into senescent mice demonstrated that bs-YHEDA entered the brain, increased ferriportin levels, reduced iron and free radical levels, decreased the consequences of neuronal necrosis and ameliorated cognitive disfunction without kidney or liver damage. bs-5YHEDA is a safe iron and free radical remover that potentially alleviates aging and Alzheimer's disease.


Assuntos
Doença de Alzheimer , Envelhecimento , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Radicais Livres , Inteligência , Ferro/uso terapêutico , Camundongos , Peptídeos
8.
Pak J Pharm Sci ; 34(3): 909-914, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34602413

RESUMO

N-Methyl-D-aspartate receptor (NMDAR)-induced antioxidation is a significant cause of neuronal injury after ischemic stroke. In a previous work, we verified the neuroprotective roles of geniposide during tMCAO in vivo. However, it remains unknown whether geniposide ameliorates injury to hippocampal neurons during Ischemic Long Term Potentiation (iLTP) induction in vitro. After induction of cells oxygen-glucose deprivation or hydrogen peroxide, the protection of geniposide evaluated by MTT assay and electrophysiological tests. In this study, we suggested neuronal cell apoptosis was attenuated by geniposide. Furthermore, field excitatory postsynaptic potentials (fEPSCs) following postischemic LTP were assessed by electrophysiological tests. Finally, we determined that medium and high doses of geniposide attenuated oxidative stress insult and improved iLTP. Importantly, these effects were abolished by cotreatment with geniposide and the GluN2A antagonist NVP. In contrast, the GluN2B inhibitor ifenprodil failed to have an effect. In conclusion, we suggest for the first time that treatment with geniposide can attenuate postischemic LTP induction in a concentration-dependent manner. We infer that GluN2A-containing NMDARs are involved in the neuroprotection induced by geniposide treatment in ischemia.


Assuntos
Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Hipóxia-Isquemia Encefálica/metabolismo , Iridoides/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Peróxido de Hidrogênio/farmacologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Técnicas In Vitro , Infarto da Artéria Cerebral Média/fisiopatologia , Neurônios/metabolismo , Oxidantes/farmacologia , Células PC12 , Piperidinas/farmacologia , Quinoxalinas/farmacologia , Ratos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo
9.
Curr Drug Targets ; 21(5): 477-498, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31736443

RESUMO

Reactive oxygen species (ROS), an important molecule inducing oxidative stress in organisms, play a key role in tumorigenesis, tumor progression and recurrence. Recent findings on ROS have shown that ROS can be used to treat cancer as they accelerate the death of tumor cells. At present, pro-oxidant drugs that are intended to increase ROS levels of the tumor cells have been widely used in the clinic. However, ROS are a double-edged sword in the treatment of tumors. High levels of ROS induce not only the death of tumor cells but also oxidative damage to normal cells, especially bone marrow hemopoietic cells, which leads to bone marrow suppression and (or) other side effects, weak efficacy of tumor treatment and even threatening patients' life. How to enhance the killing effect of ROS on tumor cells while avoiding oxidative damage to the normal cells has become an urgent issue. This study is a review of the latest progress in the role of ROS-mediated programmed death in tumor treatment and prevention and treatment of oxidative damage in bone marrow induced by ROS.


Assuntos
Antineoplásicos/farmacologia , Medula Óssea/efeitos dos fármacos , Hematopoese/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Espécies Reativas de Oxigênio/farmacologia , Antineoplásicos/uso terapêutico , Células da Medula Óssea , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/uso terapêutico
10.
Free Radic Biol Med ; 130: 458-470, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30448512

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease of the brain. It cannot be cured currently, and those suffering from AD place a great burden on their caregivers and society. AD is characterized by high levels of iron ions in the brain, which catalyze radicals that damage the neurons. Knowing that the Aß42 peptide precipitates iron by binding iron ions at amino acid residues D1, E3, H11, H13, and H14, we synthesized a 5-repeat (HAYED) sequence peptide. By treating iron-stressed SH-SY5Y cells with it and injecting it into the cerebrospinal fluid (CSF) of naturally senescence Kunming mouse, which displaying AD-similar symptoms such as learning and memory dysfunction, neuron degeneration and high level of iron in brain, we found that HAYED (5) decreased the iron and radical levels in the cell culture medium and in the CSF. Specially, the synthesized peptide prevented cell and brain damage. Furthermore, functional magnetic resonance imaging (fMRI), Morris water maze and passive avoidance tests demonstrated that the peptide ameliorated brain blood-oxygen metabolism and slowed cognitive loss in the experimental senescence mice, and clinical and blood tests showed that HAYED (5) was innoxious to the kidney, the liver and blood and offset the AD-associated inflammation and anemia.


Assuntos
Envelhecimento/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/farmacologia , Envelhecimento/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Ferro/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Doenças Neurodegenerativas/patologia , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/química , Fragmentos de Peptídeos/síntese química
11.
Drug Deliv Transl Res ; 9(1): 394-403, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30136122

RESUMO

Alzheimer's disease (AD) is currently incurable and places a large burden on the caregivers of AD patients. In the AD brain, iron is abundant, catalyzing free radicals and impairing neurons. The blood-brain barrier hampers antidementia drug delivery via circulation to the brain, which limits the therapeutic effects of drugs. Here, according to the method described by Gobinda, we synthesized a 16 lysine (K) residue-linked low-density lipoprotein receptor-related protein (LRP)-binding amino acid segment of apolipoprotein E (K16APoE). By mixing this protein with our designed therapeutic peptide HAYED, we successfully transported HAYED into an AD model mouse brain, and the peptide scavenged excess iron and radicals and decreased the necrosis of neurons, thus easing AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Apolipoproteínas E/química , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/química , Peptídeos/administração & dosagem , Animais , Apolipoproteínas E/metabolismo , Transporte Biológico , Barreira Hematoencefálica/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Ferro/química , Camundongos , Peptídeos/química
12.
Alzheimers Dement (N Y) ; 5: 717-731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921964

RESUMO

INTRODUCTION: Iron accumulates in the brain during aging, which catalyzes radical formation, causing neuronal impairment, and is thus considered a pathogenic factor in Alzheimer's disease (AD). To scavenge excess iron-catalyzed radicals and thereby protect the brain and decrease the incidence of AD, we synthesized a soluble pro-iron 5-YHEDA peptide. However, the blood-brain barrier (BBB) blocks large drug molecules from entering the brain and thus strongly reduces their therapeutic effects. However, alternative receptor- or transporter-mediated approaches are possible. METHODS: A low-density lipoprotein receptor (LDLR)-binding segment of Apolipoprotein B-100 was linked to the 5-YHEDA peptide (bs-5-YHEDA) and intracardially injected into senescent (SN) mice that displayed symptoms of cognitive impairment similar to those of people with AD. RESULTS: We successfully delivered 5-YHEDA across the BBB into the brains of the SN mice via vascular epithelium LDLR-mediated endocytosis. The data showed that excess brain iron and radical-induced neuronal necrosis were reduced after the bs-5-YHEDA treatment, together with cognitive amelioration in the SN mouse, and that the senescence-associated ferritin and transferrin increase, anemia and inflammation reversed without kidney or liver injury. DISCUSSION: bs-5-YHEDA may be a mild and safe iron remover that can cross the BBB and enter the brain to relieve excessive iron- and radical-induced cognitive disorders.

13.
J Cell Mol Med ; 21(9): 1929-1943, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28411377

RESUMO

MDR1 is highly expressed in MDR A2780DX5 ovarian cancer cells, MDR SGC7901R gastric cancer cells and recurrent tumours. It pumps cytoplasmic agents out of cells, leading to decreased drug accumulation in cells and making cancer cells susceptible to multidrug resistance. Here, we identified that miR-495 was predicted to target ABCB1, which encodes protein MDR1. To reduce the drug efflux and reverse MDR in cancer cells, we overexpressed a miR-495 mimic in SGC7901R and A2780DX cells and in transplanted MDR ovarian tumours in vivo. The results indicated that the expression of MDR1 in the above cells or tumours was suppressed and that subsequently the drug accumulation in the MDR cells was decreased, cell death was increased, and tumour growth was inhibited after treatment with taxol-doxorubicin, demonstrating increased drug sensitivity. This study suggests that pre-treatment with miR-495 before chemotherapy could improve the curative effect on MDR1-based MDR cancer.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Doxorrubicina/farmacologia , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/metabolismo , Paclitaxel/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Interferência de RNA , Rifampina/farmacologia
14.
Crit Rev Oncol Hematol ; 112: 21-30, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28325262

RESUMO

As a clonal disease of hematopoietic stem cells (HSCs), the etiology and pathogenesis of leukemia is not fully understood. Recent studies suggest that cellular homeostasis plays an essential role in maintaining the function of HSCs because dysregulation of cellular homeostasis is one of the major factors underlying the malignant transformation of HSCs. Reactive oxygen species (ROS) and autophagy, key factors regulating cellular homeostasis, are commonly observed in the human body. Autophagy can be induced by ROS through a variety of signaling pathways, and conversely inhibits ROS-induced damage to cells and tissues. ROS and autophagy coordinate to maintain cellular homeostasis. Previous studies have demonstrated that both of ROS and autophagy play important roles in the development of leukemia and are closely involved in drug resistance in leukemia. Interference with cellular homeostasis by promoting programmed leukemia cell death via ROS and autophagy has been verified to be an efficient technique in the treatment of leukemia. However, the critical roles of ROS and autophagy in the development of leukemia are largely unknown. In this review, we summarize the roles of ROS and autophagy in the pathogenesis of leukemia, which may allow the identification of novel targets and drugs for the treatment of leukemia based on the regulation of HSCs homeostasis through ROS and autophagy.


Assuntos
Autofagia/fisiologia , Leucemia/patologia , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia/metabolismo , Transdução de Sinais/fisiologia
15.
Biochem J ; 473(14): 2131-9, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27208176

RESUMO

Cell proliferation was inhibited following forced over-expression of miR-30a in the ovary cancer cell line A2780DX5 and the gastric cancer cell line SGC7901R. Interestingly, miR-30a targets the DNA replication protein RPA1, hinders the replication of DNA and induces DNA fragmentation. Furthermore, ataxia telangiectasia mutated (ATM) and checkpoint kinase 2 (CHK2) were phosphorylated after DNA damage, which induced p53 expression, thus triggering the S-phase checkpoint, arresting cell cycle progression and ultimately initiating cancer cell apoptosis. Therefore, forced miR-30a over-expression in cancer cells can be a potential way to inhibit tumour development.


Assuntos
Proliferação de Células/fisiologia , Replicação do DNA/fisiologia , MicroRNAs/fisiologia , Proteína de Replicação A/metabolismo , Apoptose/genética , Apoptose/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Senescência Celular/genética , Senescência Celular/fisiologia , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Ensaio Cometa , Replicação do DNA/genética , Histonas/metabolismo , Humanos , Imuno-Histoquímica , MicroRNAs/genética , MicroRNAs/metabolismo , Interferência de RNA/fisiologia , Proteína de Replicação A/genética
16.
Expert Rev Hematol ; 8(4): 515-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26149913

RESUMO

The mechanism of acquired aplastic anemia (AA), a bone marrow hematopoiesis failure disease, has not been fully understood. TNF-α is a pleiotropic cytokine involved in cell proliferation, differentiation and death, and inflammation through binding to specific receptors on cell membranes. Aberrant secretion of TNF-α contributes to a number of human diseases, including tumor development and inflammation. TNF-α is also an important negative regulator of hematopoiesis. Over-expression of TNF-α not only directly inhibits the proliferation and differentiation of hematopoietic cells, but also initiates the intracellular death pathway to induce hematopoietic cell death, leading to bone marrow hematopoiesis failure. In this review, we summarize the mechanisms underlying extrinsic apoptosis and necroptosis of hematopoietic cells induced by TNF-α, and discuss the role of TNF-α-induced programmed cell death in the pathogenesis of acquired AA.


Assuntos
Anemia Aplástica/etiologia , Anemia Aplástica/metabolismo , Apoptose , Fator de Necrose Tumoral alfa/metabolismo , Animais , Hematopoese , Humanos , Receptores do Fator de Necrose Tumoral
17.
J Drug Target ; 22(9): 839-48, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25019701

RESUMO

Multi-drug resistance (MDR) cancer is an intractable problem. Over-expression of drug efflux transporters such as ABCB1, ABCC1 and ABCG2 contributes to it, by which they pump drugs out of cells, and result in the decrease in the efficacy of chemotherapy. To reverse the cancer MDR, we used 3-methyladenine (3-MA) treatment on taxol or doxorubicin stressed MDR cell lines A2780DX5 and SGC7091R and xeno-tumor implanted mice. The results indicate that ABCB1, ABCC1 and ABCG2 were depressed, and the PI3K-AKT-mTOR pathway was blocked. Moreover, using FITC-labeled taxol as the indicator, we observed that the drug accumulation was enhanced in MDR cells and more cells were killed after 3-MA administration. Thus suggesting that 3-MA can reverse cancer MDR via depressing agent-efflux transporters.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/efeitos dos fármacos , Transportadores de Cassetes de Ligação de ATP/efeitos dos fármacos , Adenina/análogos & derivados , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Adenina/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Paclitaxel/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/antagonistas & inibidores
18.
Int J Clin Exp Pathol ; 7(12): 8411-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25674205

RESUMO

This study aimed to investigate the role of RIP1 and RIP3 in the pathogenesis of aplastic anemia (AA) induced by cyclophosphamide and busulphan in mice. Animals were randomly divided into three groups: the control group, the AA group, and the Nec-1 group. Mouse AA model was established by intraperitoneal injection of cyclophosphamide (40 mg/kg/d) and busulfan (20 mg/kg/d) for 12 days. The Nec-1 group mice received intraperitoneal injection of Nec-1 (2 mg/kg/d) for 12 days prior to intraperitoneal injection of cyclophosphamide (40 mg/kg/d) and busulfan (20 mg/kg/d) for 12 days. The control mice received intraperitoneal injection of equal volume of saline. At 12 h after the last intraperitoneal injection, blood and bone marrow tissues were collected from mice. Peripheral blood cells were analyzed using hematology analyzer and the histological changes of bone marrow tissues were examined using scanning electron microscopy (SEM). The levels of RIP3 and RIP3 in bone marrow were measured using Western blot analysis and the interaction of RIP1 and RIP3 proteins was investigated on the basis of immunoprecipitation analysis. ELISA was used to measure the levels of IL-6, TNF-α, and FLT-3L in bone marrow tissue supernatant. Apoptosis and necrosis of bone marrow cells were analyzed using flow cytometry. Western blot showed that the expression of RIP1 and RIP3 was significantly increases in AA mice compared to the normal controls. Immunoprecipitation detected the pro-necrotic RIP1-RIP3 complex, suggesting that RIP1 and RIP3 mediated necroptosis may involved in the damage of bone marrow cells. Compared to the AA mice, Nec-1 group mice exhibited significantly increase of peripheral blood cells and mononuclear cells in bone marrow tissues and decrease of the apoptosis/necrosis of bone marrow cells. In addition, we observed significant decrease of IL-6, TNF-α, and FLT-3L in bone marrow tissue supernatant in the Nec-1 group mice compared to AA mice. Our results suggest that Nec-1 can prevent the development of AA by inhibiting bone marrow cells necrosis and the production of inflammatory mediators. RIP1 and RIP3-mediated necroptosis may involve in the pathogenesis of AA induced by cyclophosphamide and busulfan in mice.


Assuntos
Anemia Aplástica/metabolismo , Antineoplásicos Alquilantes/toxicidade , Proteínas Ativadoras de GTPase/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Anemia Aplástica/induzido quimicamente , Animais , Western Blotting , Bussulfano/toxicidade , Ciclofosfamida/toxicidade , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imidazóis/farmacologia , Imunoprecipitação , Indóis/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Necrose/metabolismo
19.
J Biol Chem ; 287(6): 4148-56, 2012 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-22157765

RESUMO

Autophagy is activated in cancer cells during chemotherapy and often contributes to tumor chemotherapy resistance. In this study, we characterized the role of microRNA-30a (miR-30a) in the coordination of cancer cell apoptosis and autophagy, which determines the sensitivity of cancer cells to chemotherapy. First, the autophagy activity in cancer cells increased after cis-dichloro-diamine platinum (cis-DDP) or Taxol treatment, as indicated by the enhanced expression of beclin 1, a key regulator of autophagy, and increased number of LC3-positive autophagosomes. Second, miRNA screening using a TaqMan probe-based quantitative RT-PCR assay identified that miR-30a, a miRNA that targets beclin 1, was significantly reduced in tumor cells by cis-DDP treatment. Forced expression of miR-30a significantly reduced beclin 1 and the autophagy activity of tumor cells induced by cis-DDP. Third, the blockade of tumor cell autophagy activity by miR-30a expression or 3-methyladenine significantly increased tumor cell apoptosis induced by cis-DDP treatment. Finally, an in vivo tumor implantation mouse model clearly showed that elevation of miR-30a in implanted tumor cells by administration of the recombinant lentivirus expressing miR-30a strongly enhanced cis-DDP-induced apoptosis of tumor cells. In conclusion, our results demonstrate for the first time that miR-30a can sensitize tumor cells to cis-DDP via reducing beclin 1-mediated autophagy and that increasing miR-30a level in tumor cells represents a novel approach to enhance the efficacy of chemotherapy during cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas de Membrana/metabolismo , MicroRNAs/biossíntese , Proteínas de Neoplasias/metabolismo , Neoplasias/terapia , RNA Neoplásico/biossíntese , Animais , Proteínas Reguladoras de Apoptose/genética , Autofagia , Proteína Beclina-1 , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Lentivirus , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Neoplasias/genética , Neoplasias/metabolismo , RNA Neoplásico/genética , Transdução Genética , Transplante Heterólogo
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