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1.
Haematologica ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38867584

RESUMO

Platelets, produced by megakaryocytes, play unique roles in physiological processes, such as hemostasis, coagulation, and immune regulation, while also contributing to various clinical diseases. During megakaryocyte differentiation, the morphology and function of cells undergo significant changes due to the programmed expression of a series of genes. Epigenetic changes modify gene expression without altering the DNA base sequence, effectively impacting the inner workings of the cell at different stages of growth, proliferation, differentiation, and apoptosis. These modifications also play an important role in megakaryocyte development and platelet biogenesis. However, the specific mechanisms underlying epigenetic processes or the vast epigenetic regulatory network formed by their interactions remain unclear. In this review, we systematically summarize the key roles played by epigenetics in megakaryocyte development and platelet formation, including DNA methylation, histone modification, and non-coding RNA regulation. We expect our review to provide a deeper understanding of the biological processes underlying megakaryocyte development and platelet formation and to inform the development of new clinical interventions aimed at addressing platelet-related diseases and improving patient prognoses.

2.
Exp Cell Res ; 409(2): 112934, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34801561

RESUMO

Hematopoietic stem cells (HSCs) are sensitive to ionizing radiation (IR) damage, and its injury is the primary cause of bone marrow (BM) hematopoietic failure and even death after exposure to a certain dose of IR. However, the underlying mechanisms remain incompletely understood. Here we show that mitochondrial oxidative damage, which is characterized by mitochondrial reactive oxygen species overproduction, mitochondrial membrane potential reduction and mitochondrial permeability transition pore opening, is rapidly induced in both human and mouse HSCs and directly accelerates HSC apoptosis after IR exposure. Mechanistically, 5-lipoxygenase (5-LOX) is induced by IR exposure and contributes to IR-induced mitochondrial oxidative damage through inducing lipid peroxidation. Intriguingly, a natural antioxidant, caffeic acid (CA), can attenuate IR-induced HSC apoptosis through suppressing 5-LOX-mediated mitochondrial oxidative damage, thus protecting against BM hematopoietic failure after IR exposure. These findings uncover a critical role for mitochondria in IR-induced HSC injury and highlight the therapeutic potential of CA in BM hematopoietic failure induced by IR.


Assuntos
Antioxidantes/farmacologia , Araquidonato 5-Lipoxigenase/química , Ácidos Cafeicos/farmacologia , Radioisótopos de Cobalto/toxicidade , Células-Tronco Hematopoéticas/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Dano ao DNA , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Células-Tronco Hematopoéticas/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitocôndrias/efeitos da radiação
3.
Haematologica ; 106(2): 412-423, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31974197

RESUMO

Long-term hematopoietic output is dependent on hematopoietic stem cell (HSC) homeostasis which is maintained by a complex molecular network. Among these, microRNAs play crucial roles, while the underlying molecular basis has not been fully elucidated. Here, we show that miR-21 is enriched in murine HSCs, and mice with conditional knockout of miR-21 exhibit an obvious perturbation in normal hematopoiesis. Moreover, significant loss of HSC quiescence and long-term reconstituting ability are observed in the absence of miR-21. Further studies reveal that miR-21 deficiency markedly decreases the NF-κB pathway, accompanied by increased expression of PDCD4, a direct target of miR-21, in HSCs. Interestingly, overexpression of PDCD4 in wild-type HSCs generates similar phenotypes as those of miR-21-deficient HSCs. More importantly, knockdown of PDCD4 can significantly rescue the attenuation of NF-κB activity, thereby improving the defects in miR-21-null HSCs. On the other hand, we find that miR-21 is capable of preventing HSCs from ionizing radiation-induced DNA damage via activation of the NF-κB pathway. Collectively, our data demonstrate that miR-21 is involved in maintaining HSC homeostasis and function, at least in part, by regulating the PDCD4-mediated NF-κB pathway and provide a new insight into the radioprotection of HSCs.


Assuntos
MicroRNAs , NF-kappa B , Animais , Células-Tronco Hematopoéticas/metabolismo , Homeostase , Camundongos , Camundongos Knockout , MicroRNAs/genética , NF-kappa B/genética , NF-kappa B/metabolismo , Transdução de Sinais
4.
Blood ; 132(2): 210-222, 2018 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-29802222

RESUMO

It is known that insulin-like growth factor-1 (IGF-1) also functions as a hematopoietic factor, although its direct effect on thrombopoiesis remains unclear. In this study, we show that IGF-1 is able to promote CD34+ cell differentiation toward megakaryocytes (MKs), as well as the facilitation of proplatelet formation (PPF) and platelet production from cultured MKs. The in vivo study demonstrates that IGF-1 administration accelerates platelet recovery in mice after 6.0 Gy of irradiation and in mice that received bone marrow transplantation following 10.0 Gy of lethal irradiation. Subsequent investigations reveal that extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt activation mediate the effect of IGF-1 on thrombopoiesis. Notably, Akt activation induced by IGF-1 is more apparent than that of ERK1/2, compared with that of thrombopoietin (TPO) treatment. Moreover, the effect of IGF-1 on thrombopoiesis is independent of TPO signaling because IGF-1 treatment can also lead to a significant increase of platelet counts in homozygous TPO receptor mutant mice. Further analysis indicates that the activation of Akt triggered by IGF-1 requires the assistance of steroid receptor coactivator-3 (SRC-3). Therefore, our data reveal a distinct role of IGF-1 in regulating thrombopoiesis, providing new insights into TPO-independent regulation of platelet generation.


Assuntos
Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombopoese , Animais , Biomarcadores , Plaquetas/metabolismo , Diferenciação Celular , Células Cultivadas , Citoesqueleto , Técnicas de Silenciamento de Genes , Humanos , Fator de Crescimento Insulin-Like I/genética , Megacariócitos/citologia , Megacariócitos/metabolismo , Camundongos , Camundongos Knockout , Modelos Biológicos , Ativação Plaquetária , Contagem de Plaquetas , Ploidias , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Trombopoese/genética , Trombopoetina/metabolismo
5.
Blood ; 132(9): 911-923, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-29959189

RESUMO

Quiescence maintenance is an important property of hematopoietic stem cells (HSCs), whereas the regulatory factors and underlying mechanisms involved in HSC quiescence maintenance are not fully uncovered. Here, we show that steroid receptor coactivator 3 (SRC-3) is highly expressed in HSCs, and SRC-3-deficient HSCs are less quiescent and more proliferative, resulting in increased sensitivity to chemotherapy and irradiation. Moreover, the long-term reconstituting ability of HSCs is markedly impaired in the absence of SRC-3, and SRC-3 knockout (SRC-3-/-) mice exhibit a significant disruption of hematopoietic stem and progenitor cell homeostasis. Further investigations show that SRC-3 deficiency leads to enhanced mitochondrial metabolism, accompanied by overproduction of reactive oxygen species (ROS) in HSCs. Notably, the downstream target genes of peroxisome proliferator-activated receptor-coactivators 1α (PGC-1α) involved in the regulation of mitochondrial metabolism are significantly upregulated in SRC-3-deficient HSCs. Meanwhile, a significant decrease in the expression of histone acetyltransferase GCN5 accompanied by downregulation of PGC-1α acetylation is observed in SRC-3-null HSCs. Conversely, overexpression of GCN5 can inhibit SRC-3 deficiency-induced mitochondrial metabolism enhancement and ROS overproduction, thereby evidently rescuing the impairment of HSCs in SRC-3-/- mice. Collectively, our findings demonstrate that SRC-3 plays an important role in HSC quiescence maintenance by regulating mitochondrial metabolism.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Homeostase/fisiologia , Mitocôndrias/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Células-Tronco Hematopoéticas/citologia , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Coativador 3 de Receptor Nuclear/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fatores de Transcrição de p300-CBP/genética , Fatores de Transcrição de p300-CBP/metabolismo
6.
FASEB J ; 33(7): 8138-8147, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30922079

RESUMO

Hematopoietic stem cells (HSCs) establish the entire hematopoietic system and maintain lifelong hematopoiesis. Previous studies have reported the significance of microRNAs (miRNAs) in the regulation of self-renewal and differentiation of HSCs. In this study, we show that the expression of miRNA 34a (miR-34a) is markedly up-regulated in HSCs from mice subjected to ionizing radiation (IR). Reduced numbers and DNA damage repair, as well as increased apoptosis, are observed in HSCs from miR-34a-deficient mice induced by irradiation, although miR-34a is dispensable for steady-state hematopoiesis. Further investigations show that HSCs deficient in miR-34a exhibit decreased expressions of DNA repair-associated genes involved in homologous recombination and nonhomologous end joining. Competitive transplantation confirms that loss of miR-34a leads to more severe impairment of the long-term hematopoietic function of HSCs after irradiation exposure. Consistently, treating mice with an miR-34a agomir can significantly alleviate irradiation-induced DNA damage in HSCs. Our findings demonstrate that miR-34a contributes to promoting HSCs' survival after irradiation, which provides a promising approach for protecting HSCs from IR.-Zeng, H., Hu, M., Lu, Y., Zhang, Z., Xu, Y., Wang, S., Chen, M., Shen, M., Wang, C., Chen, F., Du, C., Tang, Y., Su,Y., Chen, S., Wang, J. MicroRNA 34a promotes ionizing radiation-induced DNA damage repair in murine hematopoietic stem cells.


Assuntos
Dano ao DNA , Reparo do DNA , Raios gama/efeitos adversos , Células-Tronco Hematopoéticas/metabolismo , MicroRNAs/biossíntese , Animais , Células-Tronco Hematopoéticas/patologia , Camundongos , Camundongos Knockout , MicroRNAs/genética
7.
J Pineal Res ; 68(3): e12637, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32052470

RESUMO

Melatonin (MT), endogenously secreted by the pineal gland, is closely related to multiple biological processes; however, its effect on thrombopoiesis is still not well illustrated. Here, we demonstrate that MT administration can elevate peripheral platelet levels. Analysis of different stages in thrombopoiesis reveals that MT has the capacity to promote the expansion of CD34+ and CD41+ cells, and accelerate proplatelet formation (PPF) and platelet production. Furthermore, in vivo experiments show that MT has a potential therapeutic effect on radiation-induced thrombocytopenia. The underlying mechanism suggests that both extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt signaling are involved in the processes of thrombopoiesis facilitated by MT. Interestingly, in addition to the direct regulation of Akt signaling by its upstream phosphoinositide 3-kinase (PI3K), ERK1/2 signaling is also regulated by PI3K via its effector, dual adaptor for phosphotyrosine and 3-phosphoinositides (DAPP1), in megakaryocytes after MT treatment. Moreover, the expression level of DAPP1 during megakaryocyte differentiation is closely related to the activation of ERK1/2 and Akt at different stages of thrombopoiesis. In conclusion, our data suggest that MT treatment can promote thrombopoiesis, which is modulated by the DAPP1-orchestrated activation of ERK1/2 and Akt signaling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melatonina/farmacologia , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Trombopoese/efeitos dos fármacos , Trombopoese/fisiologia , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Lipoproteínas/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Megacariócitos/efeitos dos fármacos , Megacariócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/metabolismo
8.
J Nanobiotechnology ; 18(1): 101, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32690018

RESUMO

BACKGROUND: Cell membrane-based nanocarriers are promising candidates for delivering antitumor agents. The employment of a simple and feasible method to improve the tumor-targeting abilities of these systems is appealing for further application. Herein, we prepared a platelet membrane (PM)-camouflaged antitumor nanoparticle. The effects of irradiation pretreatment on tumor targeting of the nanomaterial and on its antitumor action were evaluated. RESULTS: The biomimetic nanomaterial constructed by indocyanine green, poly(d,l-lactide-co-glycolide), and PM is termed PINPs@PM. A 4-Gy X-ray irradiation increased the proportions of G2/M phase and Caveolin-1 content in 4T1 breast cancer cells, contributing to an endocytic enhancement of PINPs@PM. PINPs@PM produced hyperthermia and reactive oxygen species upon excitation by near-infrared irradiation, which were detrimental to the cytoplasmic lysosome and resulted in cell death. Irradiation pretreatment thus strengthened the antitumor activity of PINPs@PM in vitro. Mice experiments revealed that irradiation enhanced the tumor targeting capability of PINPs@PM in vivo. When the same dose of PINPs@PM was intravenously administered, irradiated mice had a better outcome than did mice without X-ray pretreatment. CONCLUSION: The study demonstrates an effective strategy combining irradiation pretreatment and PM camouflage to deliver antitumor nanoparticles, which may be instrumental for targeted tumor therapy.


Assuntos
Antineoplásicos , Plaquetas/citologia , Membrana Celular/química , Portadores de Fármacos/química , Nanopartículas , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/efeitos da radiação , Linhagem Celular , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/efeitos da radiação , Neoplasias Experimentais/patologia , Fototerapia , Raios X
9.
Blood ; 129(19): 2667-2679, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28264799

RESUMO

Thrombosis is a common complication of chronic kidney disease (CKD), but the causes and mechanisms of CKD-associated thrombosis are not well clarified. Here, we show that platelet activity is remarkably enhanced in CKD mice, with increase of serum indoxyl sulfate (IS), a typical uremic toxin, which cannot be effectively cleared by routine dialysis. Ex vivo and in vitro experiments reveal that IS displays a distinct ability to enhance platelet activities, including elevated response to collagen and thrombin, increases in platelet-derived microparticles, and platelet-monocyte aggregates. The flow chamber assay and carotid artery thrombosis model demonstrate that IS-induced platelet hyperactivity contributes to thrombus formation. Further investigations disclose that reactive oxygen species (ROS)-mediated p38MAPK signaling plays a key role in IS-induced platelet hyperactivity. Moreover, we show that Klotho, which is expressed dominantly in the kidneys, has the capacity to counteract IS-induced platelet hyperactivity by inhibiting ROS/p38MAPK signaling, whereas Klotho reduction may aggravate the effect of IS on platelet activation in CKD and klotho+/- mice. Finally, we demonstrate that Klotho protein treatment can protect against IS-induced thrombosis and atherosclerosis in apoE-/- mice. Our findings uncover the mechanism of platelet hyperactivity induced by IS and provide new insights into the pathogenesis and treatment of CKD-associated thrombosis.


Assuntos
Plaquetas/efeitos dos fármacos , Indicã/efeitos adversos , Ativação Plaquetária/efeitos dos fármacos , Insuficiência Renal Crônica/induzido quimicamente , Trombose/induzido quimicamente , Animais , Plaquetas/patologia , Glucuronidase/administração & dosagem , Glucuronidase/metabolismo , Glucuronidase/uso terapêutico , Proteínas Klotho , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Renal Crônica/metabolismo , Trombose/tratamento farmacológico , Trombose/metabolismo
10.
Exp Cell Res ; 370(2): 409-416, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30146064

RESUMO

Ionizing radiation (IR) triggers the generation of reactive oxygen species (ROS), which shows potential roles in damaging the DNA and proteins at the nucleus, and eventually results in apoptosis and even cell death. Antioxidant agents can inhibit the generation of ROS after IR exposure. Tannic acid (TA), has an antioxidant activity involving in preventing cardiovascular and cerebrovascular diseases. However, little is known about the effects of TA on irradiation-induced apoptosis in megakaryocytes. Here, we evaluated the anti-radiation activity of TA in megakaryocytes. Our results showed that TA protected megakaryocytes from apoptosis induced by IR, attenuated IR-induced increases in the production of ROS, and inhibited the changes of mitochondrial membrane potential (MMP). Moreover, TA down-regulated NAPDH oxidase 1 (Nox1) expression, and decreased the phosphorylated levels of JNK and p38. Furthermore, JNK inhibitor could reduce apoptosis induced by X-irradiation in M07e cells. In vivo experiments confirmed that TA could promote the platelet recovery, reduce the percentage of apoptosis CD41+ megakaryocytes in bone marrow and raise survival during 30 days in mice by total body irradiation. In conclusion, TA can protecte the megakaryocytes from apoptosis caused by IR through inhibiting Nox1 expression to reduce ROS generation and repressing JNK/p38 MAPK pathway activation.


Assuntos
Apoptose/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Megacariócitos/efeitos dos fármacos , Taninos/farmacologia , Linhagem Celular Tumoral , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Megacariócitos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-29158275

RESUMO

The increasing incidence of multidrug-resistant Acinetobacter baumannii (MDRAb) infections worldwide has necessitated the development of novel antibiotics. Human defensin 5 (HD5) is an endogenous peptide with a complex architecture and antibacterial activity against MDRAb In the present study, we attempted to simplify the structure of HD5 by removing disulfide bonds. We found that the Cys2-4 bond was most indispensable for HD5 to inactivate MDRAb, although the antibacterial activity of the derivative was significantly attenuated. We then replaced the noncationic and nonhydrophobic residues with electropositive Arg to increase the antibacterial activity of HD5 derivative that contains a Cys2-4 bond, obtaining another derivative termed HD5d5. The in vitro antibacterial assay and irradiation-wound-infection animal experiment both showed that HD5d5 was much more effective than HD5 at eliminating MDRAb Further investigations revealed that HD5d5 efficiently bound to outer membrane lipid A and penetrated membranes, leading to bacterial collapse and peptide translocation. Compared to HD5, more HD5d5 molecules were located in the cytoplasm of MDRAb, and HD5d5 was more efficient at reducing the activities of superoxide dismutase and catalase, causing the accumulation of reactive oxygen species that are detrimental to microbes. In addition, HD5 failed to suppress the pathogenic outer membrane protein A of Acinetobacter baumannii (AbOmpA) at concentrations up to 50 µg/ml, whereas HD5d5 strongly bound to AbOmpA and exhibited a dramatic toxin-neutralizing ability, thus expanding the repertoire of drugs that is available to treat MDRAb infections.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Regulação Bacteriana da Expressão Gênica , Infecção dos Ferimentos/tratamento farmacológico , alfa-Defensinas/farmacologia , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/mortalidade , Infecções por Acinetobacter/patologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/crescimento & desenvolvimento , Acinetobacter baumannii/metabolismo , Animais , Antibacterianos/síntese química , Proteínas da Membrana Bacteriana Externa/antagonistas & inibidores , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Catalase/antagonistas & inibidores , Catalase/genética , Catalase/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Humanos , Lipídeo A/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ligação Proteica , Engenharia de Proteínas/métodos , Isoformas de Proteínas/síntese química , Isoformas de Proteínas/farmacologia , Transporte Proteico , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/antagonistas & inibidores , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Análise de Sobrevida , Irradiação Corporal Total , Infecção dos Ferimentos/microbiologia , Infecção dos Ferimentos/mortalidade , Infecção dos Ferimentos/patologia , alfa-Defensinas/síntese química
12.
Blood ; 127(8): 1024-35, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26644453

RESUMO

The effect of sympathetic stimulation on thrombopoiesis is not well understood. Here, we demonstrate that both continual noise and exhaustive exercise elevate peripheral platelet levels in normal and splenectomized mice, but not in dopamine ß-hydroxylase-deficient (Dbh(-/-)) mice that lack norepinephrine (NE) and epinephrine (EPI). Further investigation demonstrates that sympathetic stimulation via NE or EPI injection markedly promotes platelet recovery in mice with thrombocytopenia induced by 6.0 Gy of total-body irradiation and in mice that received bone marrow transplants after 10.0 Gy of lethal irradiation. Unfavorably, sympathetic stress-stimulated thrombopoiesis may also contribute to the pathogenesis of atherosclerosis by increasing both the amount and activity of platelets in apolipoprotein E-deficient (ApoE(-/-)) mice. In vitro studies reveal that both NE and EPI promote megakaryocyte adhesion, migration, and proplatelet formation (PPF) in addition to the expansion of CD34(+) cells, thereby facilitating platelet production. It is found that α2-adrenoceptor-mediated extracellular signal-regulated kinase 1/2 (ERK1/2) activation is involved in NE- and EPI-induced megakaryocyte adhesion and migration, and PPF is regulated by ERK1/2 activation-mediated RhoA GTPase signaling. Our data deeply characterize the role of sympathetic stimulation in the regulation of thrombopoiesis and reevaluate its physiopathological implications.


Assuntos
Plaquetas/citologia , Movimento Celular , Megacariócitos/citologia , Trombopoese , Animais , Western Blotting , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Modelos Animais de Doenças , Epinefrina/metabolismo , Epinefrina/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , Megacariócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Norepinefrina/metabolismo , Norepinefrina/farmacologia , Receptores Adrenérgicos alfa 2/metabolismo , Estresse Fisiológico/fisiologia , Sistema Nervoso Simpático/fisiologia
13.
Platelets ; 29(7): 702-708, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29119850

RESUMO

Dopamine (DA), a catecholamine neurotransmitter, is known to for its diverse roles on hematopoiesis, yet its function in thrombopoiesis remains poorly understood. This study shows that DA stimulation can directly induce platelet production from megakaryocytes (MKs) in the final stages of thrombopoiesis via a reactive oxygen species (ROS)-dependent pathway. The mechanism was suggested by the results that DA treatment could significantly elevate the ROS levels in MKs, and time-dependently activate oxidative stress-mediated signaling, including p38 mitogen-activated protein kinase, c-Jun NH2-terminal kinase, and caspase-3 signaling pathways, while the antioxidants N-acetylcysteine and L-glutathione could effectively inhibit the activation of these signaling pathways, as well as the ROS increase and platelet production triggered by DA. Therefore, our data revealed that the direct role and mechanism of DA in thrombopoiesis, which provides new insights into the function recognition of DA in hematopoiesis.


Assuntos
Plaquetas/metabolismo , Dopamina/metabolismo , Megacariócitos/metabolismo , Estresse Oxidativo , Transdução de Sinais , Trombopoese , Animais , Apoptose , Caspase 3/metabolismo , Dopamina/farmacologia , Citometria de Fluxo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Megacariócitos/citologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Trombopoese/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Blood ; 123(14): 2250-60, 2014 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-24553176

RESUMO

Human growth hormone (hGH) is known to play a functional role in regulating hematopoiesis, although its direct effect on thrombopoiesis is unclear. In this study, we show for the first time that hGH has a distinct capacity to promote the differentiation of human primary megakaryocytes derived from umbilical cord blood CD34(+) cells. In particular, hGH is potent in facilitating proplatelet formation and platelet production from cultured megakaryocytes. The stage- and time-specific activations of extracellular signal-regulated kinase 1/2 and protein kinase B signaling pathways are involved in the action of hGH. Fusion with hGH enhances the effect of a tandem dimer of thrombopoietin mimetic peptide (dTMP) on thrombopoiesis, manifested by a significant acceleration and increase of platelet production, indicating that hGH may exert a complementary and synergistic effect with c-Mpl ligands on thrombopoiesis. Accordingly, the administration of dTMP-growth hormone fusion protein led to a rapid platelet recovery in mice with severe thrombocytopenia induced by 6.5 Gy total body irradiation, thereby markedly abridging the duration of thrombocytopenia crisis (platelets <150 × 10(9)/L), in comparison with high doses of dTMP. These findings demonstrate the functional role of growth hormone in promoting thrombopoiesis and provide a promising avenue for the treatment of severe thrombocytopenia.


Assuntos
Hormônio do Crescimento Humano/farmacologia , Megacariócitos/efeitos dos fármacos , Peptídeos/farmacologia , Receptores de Trombopoetina/agonistas , Trombopoese/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Sinergismo Farmacológico , Humanos , Ligantes , Masculino , Megacariócitos/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/química
15.
Sci Total Environ ; 920: 171124, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38382609

RESUMO

While microalgal-bacterial membrane bioreactors (microalgal-bacterial MBRs) have risen as an important technique in the realm of sustainable wastewater treatment, the membrane fouling caused by free microalgae is still a significant challenge to cost-effective operation of the microalgal-bacterial MBRs. Addressing this imperative, the current study investigated the influence of magnesium ion (Mg2+) addition on the biological dynamics and membrane fouling characteristics of the laboratory-scale submerged microalgal-bacterial MBRs. The results showed that Mg2+, important in augmenting photosynthetic process, yielded a biomass concentration of 2.92 ± 0.06 g/L and chlorophyll-a/MLSS (mixed liquor suspended solids) of 33.95 ± 1.44 mg/g in the RMg (Mg2+ addition test group). Such augmentation culminated in elevated total nitrogen and phosphorus removal efficiencies, clocking 81.73 % and 80.98 % respectively in RMg. Remarkably, despite the enhanced microalgae activity and concentration in RMg, the TMP growth rate declined by a significant 46.8 % compared to R0. Detailed characterizations attributed reduced membrane fouling of RMg to a synergy of enlarged floc size and reduced EPS contents. This transformation is intrinsically linked to the bridging action of Mg2+ and its role in creating a non-stressed ecological environment for the microalgal-bacterial MBR. In conclusion, the addition of Mg2+ in the microalgal-bacterial MBR appears an efficient approach, improving the efficiency of pollutant treatment and mitigating fouling, which potentially revolutionizes cost-effective applications and propels the broader acceptance of microalgal-bacterial MBRs. It also of great importance to promote the development and application of microalgal-bacterial wastewater treatment technology.


Assuntos
Incrustação Biológica , Microalgas , Águas Residuárias , Incrustação Biológica/prevenção & controle , Membranas Artificiais , Reatores Biológicos/microbiologia , Bactérias , Esgotos
16.
World J Gastrointest Surg ; 16(7): 2167-2174, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39087123

RESUMO

BACKGROUND: In recent years, pure laparoscopic radical surgery for Bismuth-Corlette type III and IV hilar cholangiocarcinoma (HCCA) has been preliminarily explored and applied, but the surgical strategy and safety are still worthy of further improvement and attention. AIM: To summarize and share the application experience of the emerging strategy of "hepatic hilum area dissection priority, liver posterior separation first" in pure laparoscopic radical resection for patients with HCCA of Bismuth-Corlette types III and IV. METHODS: The clinical data and surgical videos of 6 patients with HCCA of Bismuth-Corlette types III and IV who underwent pure laparoscopic radical resection in our department from December 2021 to December 2023 were retrospectively analyzed. RESULTS: Among the 6 patients, 4 were males and 2 were females. The average age was 62.2 ± 11.0 years, and the median body mass index was 20.7 (19.2-24.1) kg/m2. The preoperative median total bilirubin was 57.7 (16.0-155.7) µmol/L. One patient had Bismuth-Corlette type IIIa, 4 patients had Bismuth-Corlette type IIIb, and 1 patient had Bismuth-Corlette type IV. All patients successfully underwent pure laparoscopic radical resection following the strategy of "hepatic hilum area dissection priority, liver posterior separation first". The operation time was 358.3 ± 85.0 minutes, and the intraoperative blood loss volume was 195.0 ± 108.4 mL. None of the patients received blood transfusions during the perioperative period. The median length of stay was 8.3 (7.0-10.0) days. Mild bile leakage occurred in 2 patients, and all patients were discharged without serious surgery-related complications. CONCLUSION: The emerging strategy of "hepatic hilum area dissection priority, liver posterior separation first" is safe and feasible in pure laparoscopic radical surgery for patients with HCCA of Bismuth-Corlette types III and IV. This strategy is helpful for promoting the modularization and process of pure laparoscopic radical surgery for complicated HCCA, shortens the learning curve, and is worthy of further clinical application.

17.
World J Gastrointest Surg ; 16(2): 503-510, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38463365

RESUMO

BACKGROUND: Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment, the feasibility and safety of this approach for laparoscopic pancreaticoduodenectomy (LPD) require further clinical evaluation and investigation. AIM: To explore the application value of the "five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients. METHODS: A total of 52 patients who underwent LPD via the "five steps four quadrants" modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively. The patients' body mass index (BMI), preoperative laboratory indices, intraoperative variables and postoperative complications were recorded. The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed. RESULTS: Among the 52 patients, 36 were males and 16 were females, and the average age was 62.2 ± 11.0 years. There were 26 patients with pancreatic head cancer, 16 patients with periampullary cancer, and 10 patients with distal bile duct cancer. The BMI was 22.3 ± 3.3 kg/m², and the median total bilirubin (TBIL) concentration was 57.7 (16.0-155.7) µmol/L. All patients successfully underwent the "five steps four quadrants" modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage. Correlation analysis revealed significant associations between preoperative BMI (r = 0.3581, P = 0.0091), TBIL level (r = 0.2988, P = 0.0341), prothrombin time (r = 0.3018, P = 0.0297) and lymph node dissection time. Moreover, dissection time was significantly correlated with intraoperative blood loss (r = 0.7744, P < 0.0001). Further stratified analysis demonstrated that patients with a preoperative BMI ≥ 21.9 kg/m² and a TIBL concentration ≥ 57.7 µmol/L had significantly longer lymph node dissection times (both P < 0.05). CONCLUSION: The "five steps four quadrants" modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD. This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve; thus, it is worthy of further clinical promotion and application.

18.
Pathol Res Pract ; 254: 154987, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237400

RESUMO

The cell proliferation protein 123 (CDC123) is involved in the synthesis of the eukaryotic initiation factor 2 (eIF2), which regulates eukaryotic translation. Although CDC123 is considered a candidate oncogene in breast cancer, its expression and role in Hepatocellular Carcinoma (HCC) remain unknown. Herein, we obtained the CDC123 RNA-seq and clinical prognostic data from the TCGA database. The mRNA level revealed that CDC123 was highly expressed in HCC patients, and Kaplan-Meier analysis implied better prognoses in HCC patients with low CDC123 expression (P < 0.001). The multivariate Cox analysis revealed that the CDC123 level was an independent prognostic factor (P < 0.001). We further confirmed a high CDC123 expression in HCC cell lines. Additionally, we found that CDC123 knockdown in HCC cell lines significantly inhibited cellular proliferation, invasion, and migration. Moreover, CDC123 was co-expressed with the CDK5 Regulatory Subunit-Associated Protein 1 Like 1 (CDKAL1), whose mRNA level was decreased after silencing CDC123. Therefore, we hypothesized that CDC123 promotes HCC progression by regulating CDKAL1.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proliferação de Células/genética , Prognóstico , RNA Mensageiro , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Movimento Celular/genética , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
19.
Appl Microbiol Biotechnol ; 97(7): 2885-94, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23149755

RESUMO

The 14-mer thrombopoietin mimetic peptide (TMP), especially in the form of dimer, displayed potent megakaryocytopoiesis activity in vitro. However, it is difficult to prepare such short peptide with high bioactivity through gene-engineering approaches. In this study, a chimeric protein containing a tandem dimer of TMP (dTMP) fused to human growth hormone (hGH), a kind of hematopoietic growth factor that activates the same signal pathways as thrombopoietin, was produced in Escherichia coli by soluble expression. By rational utilization of the XmnI and EcoRV restriction sites, a PCR fragment encoding dTMP-GH was inserted into the plasmid vector pMAL-p2X at the position right after Xa factor cleavage site, in frame with maltose-binding protein (MBP) gene. Under optimized conditions, a high-level expression of soluble MBP-dTMP-GH fusion protein was obtained. By application of amylose resin chromatography, Xa factor digestion, hydrophobic chromatography followed by gel filtration, the dTMP-GH fusion protein was separated. Finally, a relatively high yield of dTMP-GH fusion protein with high purity (>98%) and without redundant amino acid was achieved, as identified by high-performance liquid chromatography, mass spectrometry, and amino acid sequencing. The functional assays showed that dTMP-GH could promote the proliferation of megakaryoblast cells and maturation of murine megakaryocytes derived from bone marrow, in a dose-dependent manner. Moreover, an enhanced effect of dTMP-GH on megakaryocytopoiesis was found as compared with equimolar concentration of dTMP and rhGH. This work provides a new avenue to generate thrombopoietic agents based on TMP.


Assuntos
Escherichia coli/genética , Hormônio do Crescimento Humano/isolamento & purificação , Peptídeos/isolamento & purificação , Animais , Diferenciação Celular , Proliferação de Células , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Hormônio do Crescimento Humano/genética , Hormônio do Crescimento Humano/metabolismo , Humanos , Espectrometria de Massas , Células Progenitoras de Megacariócitos/efeitos dos fármacos , Camundongos , Peptídeos/genética , Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de Proteína
20.
Immun Inflamm Dis ; 11(10): e1044, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37904705

RESUMO

OBJECTIVE: To assess the effectiveness and safety of the total glucosides of paeony (TGP) combined with hydroxychloroquine (HCQ) on the treatment of primary Sjögren's syndrome (pSS) by conducting a meta-analysis. METHODS: Eight databases were searched for randomized controlled trials (RCTs) reporting the use of TGP combined with HCQ for pSS, which are before May 10, 2022. Meta-analyses were performed on disappeared clinical symptoms (dry mouth and dry eyes), Schirmer's test, saliva flow test, erythrocyte sedimentation rate (ESR), index of immunoglobulin G (IgG), immunoglobulin M (IgM), immunoglobulin A (IgA), and adverse events (AEs). The Revman 5.4 software was used for this meta-analysis. RESULTS: Seven RCTs which included 632 participants were identified. The pooled results showed significant differences in clinical symptoms disappear (dry mouth and dry eyes) (p = .0004), IgM (p < .00001), IgA (p < .00001), salivary flow rate (p < .00001) and Schirmer's test (p = .02) in the comparison of TGP combined with HCQ and HCQ alone. For the IgG and ESR, both pooled and subgroup analyses showed that TGP + HCQ was superior to HCQ alone. For the safety analysis, no significant differences in AEs (p = .39) was revealed. The more frequently seen adverse reactions were diarrhea, vomit and there was no severe adverse events were reported in TGP + HCQ group. CONCLUSION: Therefore, TGP + HCQ can be considered to be a potentially valid and safe combination for the treatment of pSS in the clinic.


Assuntos
Síndromes do Olho Seco , Paeonia , Síndrome de Sjogren , Humanos , Hidroxicloroquina/efeitos adversos , Síndrome de Sjogren/tratamento farmacológico , Síndrome de Sjogren/diagnóstico , Glucosídeos/efeitos adversos , Síndromes do Olho Seco/tratamento farmacológico , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M/uso terapêutico
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