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1.
Sci Rep ; 14(1): 23829, 2024 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-39394459

RESUMEN

The platelet-derived growth factor (PDGF) family contributes to the progression of steatohepatitis; however, changes in and the characteristics of isoform-specific expression remain unclear. Since diabetes is a major driver of metabolic dysfunction-associated steatohepatitis (MASH), we characterized the mouse model of diabetic MASH (dMASH) by focusing on PDGF signaling. Pdgfa-d expression was markedly higher in hepatic stellate cells among flow-sorted cells in control mice and also increased in dMASH. In contrast, a reanalysis of human single-cell RNA-Seq data showed the distinct distribution of each PDGF isoform with disease progression. Furthermore, inflammation and fibrosis in the liver were less severe in diabetic MASH using tamoxifen-induced PDGF receptor ß (PDGFRß)-deficient mice (KO) than in control dMASH using floxed mice (FL) at 12 weeks old. Despite the absence of tumors, the expression of tumor-related genes was lower in KO than in FL. Tumorigenesis was significantly lower in 20-week-old KO. An Ingenuity Pathway Analysis of differentially expressed miRNA between FL and KO identified functional networks associated with hepatotoxicity and cancer. Therefore, PDGFRß signals play important roles in the progression of steatohepatitis and tumorigenesis in MASH, with the modulation of miRNA expression posited as a potential underlying mechanism.


Asunto(s)
Carcinogénesis , Ratones Noqueados , Receptor beta de Factor de Crecimiento Derivado de Plaquetas , Animales , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Ratones , Carcinogénesis/genética , Carcinogénesis/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Hígado Graso/metabolismo , Hígado Graso/genética , Hígado Graso/patología , Modelos Animales de Enfermedad , Masculino , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Factor de Crecimiento Derivado de Plaquetas/genética , Hígado/metabolismo , Hígado/patología , Células Estrelladas Hepáticas/metabolismo , Transducción de Señal , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/genética
2.
J Hematol Oncol ; 17(1): 95, 2024 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-39396039

RESUMEN

Due to spatial and genomic independence, mitochondria possess a translational mechanism distinct from that of cytoplasmic translation. Several regulators participate in the modulation of mitochondrial translation. Mitochondrial translation is coordinated with cytoplasmic translation through stress responses. Importantly, the inhibition of mitochondrial translation leads to the inhibition of cytoplasmic translation and metabolic disruption. Therefore, defects in mitochondrial translation are closely related to the functions of hematopoietic cells and various immune cells. Finally, the inhibition of mitochondrial translation is a potential therapeutic target for treating multiple hematologic malignancies. Collectively, more in-depth insights into mitochondrial translation not only facilitate our understanding of its functions in hematopoiesis, but also provide a basis for the discovery of new treatments for hematological malignancies and the modulation of immune cell function.


Asunto(s)
Neoplasias Hematológicas , Hematopoyesis , Mitocondrias , Biosíntesis de Proteínas , Humanos , Mitocondrias/metabolismo , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patología , Animales
3.
Mol Ther Methods Clin Dev ; 32(4): 101323, 2024 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-39309261

RESUMEN

X-linked lymphoproliferative disease (XLP1) results from SH2D1A gene mutations affecting the SLAM-associated protein (SAP). A regulated lentiviral vector (LV), XLP-SMART LV, designed to express SAP at therapeutic levels in T, NK, and NKT cells, is crucial for effective gene therapy. We experimentally identified 34 genomic regulatory elements of the SH2D1A gene and designed XLP-SMART LVs to emulate the lineage and stage-specific control of SAP. We screened them for their on-target enhancer activity in T, NK, and NKT cells and their off-target enhancer activity in B cell and myeloid populations. In combination, three enhancer elements increased SAP promoter expression up to 4-fold in on-target populations in vitro. NSG-Tg(Hu-IL15) xenograft studies with XLP-SMART LVs demonstrated up to 7-fold greater expression in on-target cells over a control EFS-LV, with no off-target expression. The XLP-SMART LVs exhibited stage-specific T and NK cell expression in peripheral blood, bone marrow, spleen, and thymic tissues (mimicking expression patterns of SAP). Transduction of XLP1 patient CD8+ T cells or BM CD34+ cells with XLP-SMART LVs restored restimulation-induced cell death and NK cytotoxicity to wild-type levels, respectively. These data demonstrate that it is feasible to create a lineage and stage-specific LV to restore the XLP1 phenotype by gene therapy.

4.
Br J Haematol ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39313909

RESUMEN

Patients with haematological malignancies often exhibit reduced antibody responses to severe acute respiratory syndrome-related coronavirus vaccines, especially those who have undergone allogeneic haematopoietic stem cell transplantation (HSCT). Limited data exist on vaccine efficacy in this group. In a retrospective analysis of 75 post-HSCT patients, we assessed serologic responses to one to four doses of Pfizer-BioNTech (PB), AstraZeneca (AZ) or Moderna (MU) vaccines within 2 years post-transplant. Seroconversion rates were 50.7%, 78%, 79% and 83% after the first to fourth doses respectively. The median time from allograft to first re-vaccination was 145 days (range 79-700). Failure to respond to the first vaccine dose was linked to acute GVHD (p = 0.042) and rituximab treatment within 12 months (p = 0.019). A trend was observed with chronic GVHD and seroconversion failure after the second (p = 0.07) and third (p = 0.09) doses. Patients vaccinated before HSCT showed better antibody responses post-transplant (p = 0.019). Coronavirus disease 2019 incidence was 16%, with 17% hospitalized and one death (8%). Despite low initial seroconversion rates post-HSCT, antibody responses improved after the second dose. Early full re-vaccination and boosters post-HSCT are recommended to reduce mortality. Rituximab use and active GVHD were identified as risk factors, warranting further investigation.

5.
Plant Foods Hum Nutr ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39298074

RESUMEN

Apple polyphenols (APs) have gained attention for their various bioactivities, while no studies on anti-liver fibrosis activity are reported. This study evaluated the protective effect of APs on liver fibrosis using LPS-treated activated HSC-T6 cells and alcohol-treated liver fibrosis (ALF) mice. The results indicated that APs inhibited HSC-T6 cells activation in vitro and reduced the level of serum hyaluronic acid (HA) (p < 0.05), decreased fibrogenesis marker expression (p < 0.05), thereby alleviating ALF. In addition, APs (800 mg/kg b.w.) decreased the Firmicutes/Bacteroidetes ratio (p < 0.05) in ALF mice, inhibited LPS accumulation in the liver tissue and serum (p < 0.05), and significantly inhibited the TLR4/NF-κB/TGF-ß signaling in mice liver. In conclusion, APs markedly ameliorated ALF, possibly by improving gut microbiota homeostasis, decreasing the translocation of bacterial endotoxins to the blood, and suppressing the TLR4/NF-κB/TGF-ß signaling pathway, indicating its potential as lead compounds for functional foods and/or drugs against ALF.

6.
Front Endocrinol (Lausanne) ; 15: 1450349, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39314524

RESUMEN

Introduction: Autosomal recessive osteopetrosis (ARO) is a rare genetic disease, characterized by increased bone density due to defective osteoclast function. Most of the cases are due to TCIRG1 gene mutation, leading to severe bone phenotype and death in the first years of life. The standard therapy is the hematopoietic stem cell transplantation (HSCT), but its success is limited by several constraints. Conversely, gene therapy (GT) could minimize the immune-mediated complications of allogeneic HSCT and offer a prompt treatment to these patients. Methods: The Tcirg1-defective oc/oc mouse model displays a short lifespan and high bone density, closely mirroring the human condition. In this work, we exploited the oc/oc neonate mice to optimize the critical steps for a successful therapy. Results: First, we showed that lentiviral vector GT can revert the osteopetrotic bone phenotype, allowing long-term survival and reducing extramedullary haematopoiesis. Then, we demonstrated that plerixafor-induced mobilization can further increase the high number of HSPCs circulating in peripheral blood, facilitating the collection of adequate numbers of cells for therapeutic purposes. Finally, pre-transplant non-genotoxic conditioning allowed the stable engraftment of HSPCs, albeit at lower level than conventional total body irradiation, and led to long-term survival and correction of bone phenotype, in the absence of acute toxicity. Conclusion: These results will pave the way to the implementation of an effective GT protocol, reducing the transplant-related complication risks in the very young and severely affected ARO patients.

7.
Int J Mol Sci ; 25(18)2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39337516

RESUMEN

Adult stem cell therapy via intramyocardial injection of autologous CD34+ stem cells has been shown to improve exercise capacity and reduce angina frequency and mortality in patients with refractory angina (RA). However, the cost of such therapy is a limitation to its adoption in clinical practice. Our goal was to determine whether the less costly, less invasive, and widely accessible, FDA-approved alternative treatment for RA patients, known as enhanced external counterpulsation (EECP), mobilizes endogenous CD34+ stem cells and whether such mobilization is associated with the clinical benefits seen with intramyocardial injection. We monitored changes in circulating levels of CD34+/CD133+ and CD34+/KDR+ cells in RA patients undergoing EECP therapy and in a comparator cohort of RA patients undergoing an exercise regimen known as cardiac rehabilitation. Changes in exercise capacity in both cohorts were monitored by measuring treadmill times (TT), double product (DP) scores, and Canadian Cardiovascular Society (CCS) angina scores between pre- and post-treatment treadmill stress tests. Circulating levels of CD34+/CD133+ cells increased in patients undergoing EECP and were significant (ß = -2.38, p = 0.012) predictors of improved exercise capacity in these patients. CD34+/CD133+ cells isolated from RA patients could differentiate into endothelial cells, and their numbers increased during EECP therapy. Our results support the hypothesis that mobilized CD34+/CD133+ cells repair vascular damage and increase collateral circulation in RA patients. They further support clinical interventions that can mobilize adult CD34+ stem cells as therapy for patients with RA and other vascular diseases.


Asunto(s)
Antígeno AC133 , Angina de Pecho , Antígenos CD34 , Contrapulsación , Células Progenitoras Endoteliales , Humanos , Antígeno AC133/metabolismo , Antígenos CD34/metabolismo , Femenino , Masculino , Angina de Pecho/terapia , Angina de Pecho/sangre , Angina de Pecho/metabolismo , Persona de Mediana Edad , Células Progenitoras Endoteliales/metabolismo , Células Progenitoras Endoteliales/citología , Anciano , Contrapulsación/métodos , Movilización de Célula Madre Hematopoyética/métodos
8.
Biochem Biophys Res Commun ; 734: 150661, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39243675

RESUMEN

Hematopoietic stem progenitor cells (HSPCs) give rise to the hematopoietic system, maintain hematopoiesis throughout the lifespan, and undergo molecular and functional changes during their development and aging. The importance of hematopoietic stem cell (HSC) biology has led to their extensive characterization at genomic and transcriptomic levels. However, the proteomics of HSPCs throughout the murine lifetime still needs to be fully completed. Here, using mass spectrometry (MS)-based quantitative proteomics, we report on the dynamic changes in the proteome of HSPCs from four developmental stages in the fetal liver (FL) and the bone marrow (BM), including E14.5, young (2 months), middle-aged (8 months), and aging (18 months) stages. Proteomics unveils highly dynamic protein kinetics during the development and aging of HSPCs. Our data identify stage-specific developmental features of HSPCs, which can be linked to their functional maturation and senescence. Our proteomic data demonstrated that FL HSPCs depend on aerobic respiration to meet their proliferation and oxygen supply demand, while adult HSPCs prefer glycolysis to preserve the HSC pool. By functional assays, we validated the decreased mitochondrial metabolism, glucose uptake, reactive oxygen species (ROS) production, protein synthesis rate, and increased glutathione S-transferase (GST) activity during HSPC development from fetal to adult. Distinct metabolism pathways and immune-related pathways enriched in different HSPC developmental stages were revealed at the protein level. Our study will have broader implications for understanding the mechanism of stem cell maintenance and fate determination and reversing the HSC aging process.

9.
FEBS Lett ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39108012

RESUMEN

Hematopoietic stem cells (HSC) maintain blood production throughout life. Nevertheless, HSC functionality deteriorates upon physiological aging leading to the increased prevalence of haematological diseases and hematopoietic malignancies in the elderly. Deubiquitinating enzymes (DUBs) by reverting protein ubiquitination ensure proper proteostasis, a key process in HSC maintenance and fitness.

10.
J Ethnopharmacol ; 335: 118712, 2024 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-39173724

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Yajieshaba (YJSB), approved by the Yunnan Provincial Food and Drug Administration in 2008, are known for their anti-inflammatory, antiviral, and pro-apoptotic properties, effectively treating Hepatic fibrosis (HF). However, its mechanism of action remains unclear. AIM OF THE STUDY: The objective of this investigation is to explore how YJSB influences the TGF-ß1/Smad signaling pathway as a strategy for reducing HF. METHODS: The establishment of a HF model in mice involved ligation of the common bile duct, followed by administration of YJSB. Body and liver weights were measured, and the liver index calculated. Serum levels of ALT, AST, ALP, TBA, and TBIL were assessed using colorimetric methods. Additionally, liver homogenates were analyzed for PIIINP, Col-IV, LN, HA, and Hyp, as well as TGF-ß1 activity, using ELISA. Histological analyses of liver sections, stained with H&E, Ag, and Masson's trichrome, were performed to examine inflammation and the accumulation of collagen and reticular fibers. These studies aimed to elucidate the pharmacodynamic effects of YJSB on HF in mice with bile duct obstruction. The target pathways of YJSB were preliminarily identified through immunofluorescence detection of TGF-ß1, P-Smad2L, P-Smad2C, P-Smad3L, P-Smad3C, and Smad4 proteins. In vitro experiments included the induction of hepatic stellate cell (HSC-T6) activation by H2O2. A cell injury model was established for HSC-T6, and the CCK-8 assay was used to determine the optimal YJSB concentration and treatment duration. After pirfenidone (PFD) administration, which inhibits the TGF-ß1/Smad pathway, the effects of YJSB on HSC-T6 cell proliferation were observed. ELISA assays quantified Col-III, α-SMA, and Col-I in cell lysates to assess YJSB's impact on collagen synthesis in HSC-T6 cells. Western blot analysis was performed to assess the protein levels within the TGF-ß1/Smad signaling cascade. RESULTS: In the HF mouse model, administration of YJSB notably augmented the body weight and reduced the liver index. Concurrently, there was an elevation in serum concentrations of ALP, AST, ALT, TBA, and TBIL. Similarly, in the liver homogenates of HF mice, increases were observed in the levels of HA, PIIINP, Col-IV, LN, Hyp, and TGF-ß1. Histological assessments using H&E, Ag, and Masson stains indicated a substantial diminution in liver tissue damage. Through immunofluorescence analysis, it was discerned that YJSB modulated the expression of TGF-ß1, P-Smad2L, P-Smad2C, and P-Smad3L downwards, while elevating P-Smad3C and Smad4 protein expressions. Additional investigations revealed a significant reduction in α-SMA, Col-I, and Col-III levels in cell culture fluids, suggesting a decrease in collagen synthesis and a protective role against cellular damage. Western blot analyses demonstrated that the TGF-ß1/Smad pathway inhibitor, PFD, acted in synergy with YJSB, enhancing its regulatory effects on this pathway, decreasing levels of TGF-ß1, P-Smad2L, P-Smad2C, P-Smad3L, and promoting the expression of P-Smad3C. CONCLUSIONS: YJSB demonstrates a pharmacodynamic effect against HF, enhancing liver functionality and effectively mitigating the damage associated with bile duct obstruction. The proposed action mechanism of YJSB involves modulation of the TGF-ß1/Smad signaling pathway. Research indicates that YJSB might play a role in suppressing the movement, programmed cell death, and activation of HSC-T6, potentially decelerating the advancement of hepatic fibrosis.


Asunto(s)
Colestasis , Células Estrelladas Hepáticas , Peróxido de Hidrógeno , Cirrosis Hepática , Transducción de Señal , Factor de Crecimiento Transformador beta1 , Animales , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Factor de Crecimiento Transformador beta1/metabolismo , Ratones , Masculino , Peróxido de Hidrógeno/metabolismo , Colestasis/metabolismo , Colestasis/patología , Colestasis/tratamiento farmacológico , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Transducción de Señal/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Línea Celular , Modelos Animales de Enfermedad , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Proteínas Smad/metabolismo , Ratones Endogámicos C57BL , Proteína Smad2/metabolismo
11.
Int J Pharm ; 664: 124607, 2024 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-39159856

RESUMEN

The vicious crosstalk among capillarization of hepatic sinusoidal endothelial cells (LSECs), activation of hepatic stellate cells (aHSCs), and hepatocyte damage poses a significant impediment to the successful treatment of liver fibrosis. In this study, we propose a sequential combination therapy aimed at disrupting the malignant crosstalk and reshaping the benign microenvironment while repairing damaged hepatocytes to achieve effective treatment of liver fibrosis. Firstly, H-subunit apoferrin (Ferritin) was adopted to load platycodonin D (PLD) and MnO2, forming ferritin@MnO2/PLD (FMP) nanoparticles, which exploited the high affinity of ferritin for the highly expressed transferrin receptor 1 (TfR1) to achieve the precise targeted delivery of FMP in the liver. Upon PLD intervention, restoration of the fenestration pores in capillarized LSECs was facilitated by modulating the phosphatidyl inositol 3-kinase/protein kinase B (PI3K/AKT) and Kruppel Like Factor 2 (KLF2) signaling pathways both in vitro and in vivo, enabling efficient entry of FMP into the Disse space. Subsequently, FMP NPs effectively inhibited HSC activation by modulating the TLR2/TLR4/NF-κB-p65 signaling pathway. Moreover, FMP NPs efficiently scavenged reactive oxygen species (ROS) and mitigated the expression of inflammatory mediators, thereby reshaping the microenvironment to support hepatocyte repair. Finally, administration of bone marrow mesenchymal stem cells (BMMSCs) was employed to promote the regeneration and functional recovery of damaged hepatocytes. In conclusion, the combined sequential therapy involving FMP and BMMSCs effectively attenuated liver fibrosis induced by CCl4 administration, resulting in significant amelioration of the fibrotic condition. The therapeutic strategy outlined in this study underscores the significance of disrupting the deleterious cellular interactions and remodeling the microenvironment, thereby presenting a promising avenue for clinical intervention in liver fibrosis.


Asunto(s)
Ferritinas , Células Estrelladas Hepáticas , Animales , Ferritinas/metabolismo , Masculino , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Nanopartículas/administración & dosificación , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/terapia , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ratones , Sistemas de Liberación de Medicamentos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Hígado/metabolismo , Hígado/efectos de los fármacos , Hígado/patología
12.
Bioengineering (Basel) ; 11(8)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39199704

RESUMEN

Platelet-rich fibrin (PRF), originally used to support soft tissue healing, is also considered a therapeutic option for treating oral lichen planus and leukoplakia. The progression from the two premalignant lesions to the aggressive malignant oral squamous cell carcinoma involves an inflammatory process linked to chemokine expression. Thus, there is a rationale for studying how PRF modulates the expression of chemokines in oral squamous carcinoma cells. To this aim, we expose the oral squamous carcinoma cell line HSC2 to IL1ß and TNFα either alone or in the presence of lysates obtained from solid PRF membranes. We report here that in HSC2 cells, PRF lysates significantly reduce the forced transcription of chemokines, e.g., CXCL1, CXCL2, CXCL8, CXCL10, and CCL5. Moreover, PRF lysates attenuate the nuclear translocation of p65 in HSC2 oral epithelial cells when exposed to IL1ß and TNFα. PRF lysates further reduce chemokine expression provoked by poly:IC HMW. Even though less pronounced, PRF lysates reduce IL1ß- and TNFα-induced chemokine expression in TR146 cells. In primary oral epithelial cells, however, PRF lysates increase the basal expression of CXCL1, CXCL2 and CXCL8. Thus, PRF can exert a biphasic effect on chemokine expression in oral squamous cell carcinoma cell lines and primary oral epithelial cells. These findings suggest that PRF may reduce inflammation in a malignant environment while provoking an immunological response in healthy oral epithelium.

13.
Front Cell Dev Biol ; 12: 1418296, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184917

RESUMEN

Introduction: Aromatic (Ar)-turmerone is a bioactive component of turmeric oil obtained from Curcuma longa. We recently identified a novel analog (A2) of ar-turmerone that protects dopaminergic neurons from toxic stimuli by activating nuclear factor erythroid 2-related factor 2 (Nrf2). D-cysteine increases Nrf2, leading to the activation of chaperone-mediated autophagy (CMA), a pathway in the autophagy-lysosome protein degradation system, in primary cultured cerebellar Purkinje cells. In this study, we attempted to identify novel analogs of ar-turmerone that activate Nrf2 more potently and investigated whether these analogs activate CMA. Methods: Four novel analogs (A4-A7) from A2 were synthesized. We investigated the effects of A2 and novel 4 analogs on Nrf2 expression via immunoblotting and CMA activity via fluorescence observation. Results: Although all analogs, including A2, increased Nrf2 expression, only A4 activated CMA in SH-SY5Y cells. Additionally, A4-mediated CMA activation was not reversed by Nrf2 inhibition, indicating that A4 activated CMA via mechanisms other than Nrf2 activation. We focused on p38, which participates in CMA activation. Inhibition of p38 significantly prevented A4-mediated activation of CMA. Although all novel analogs significantly increased the phosphorylation of p38 6 h after drug treatment, only A4 significantly increased phosphorylation 24 h after treatment. Finally, we revealed that A4 protected SH-SY5Y cells from the cytotoxicity of rotenone, and that this protection was reversed by inhibiting p38. Conclusion: These findings suggest that the novel ar-turmerone analog, A4, activates CMA and protects SH-SY5Y cells through the persistent activation of p38.

14.
Ann Transl Med ; 12(4): 63, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39118939

RESUMEN

Hematopoiesis requires a complex interplay between the hematopoietic stem and progenitor cells and the cells of the bone marrow microenvironment (BMM). The BMM is heterogeneous, with different regions having distinct cellular, molecular, and metabolic composition and function. Studies have shown that this niche is disrupted in patients with acute myeloid leukemia (AML), which plays a crucial role in disease progression. This review provides a comprehensive overview of the components of vascular and endosteal niches and the molecular mechanisms by which they regulate normal hematopoiesis. We also discuss how these niches are modified in the context of AML, into a disease-promoting niche and how the modified niches in turn regulate AML blast survival and proliferation. We focus on mechanisms of modifications in structural and cellular components of the bone marrow (BM) niche by the AML cells and its impact on leukemic progression and patient outcome. Finally, we also discuss mechanisms by which the altered BM niche protects AML blasts from treatment agents, thereby causing therapy resistance in AML patients. We also summarize ongoing clinical trials that target various BM niche components in the treatment of AML patients. Hence, the BM niche represents a promising target to treat AML and promote normal hematopoiesis.

15.
Acta Pharmacol Sin ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103531

RESUMEN

Liver fibrosis, one of the leading causes of morbidity and mortality worldwide, lacks effective therapy. The activation of hepatic stellate cells (HSCs) is the dominant event in hepatic fibrogenesis. Luteolin-7-diglucuronide (L7DG) is the major flavonoid extracted from Perilla frutescens and Verbena officinalis. Their beneficial effects in the treatment of liver diseases were well documented. In this study we investigated the anti-fibrotic activities of L7DG and the potential mechanisms. We established TGF-ß1-activated mouse primary hepatic stellate cells (pHSCs) and human HSC line LX-2 as in vitro liver fibrosis models. Co-treatment with L7DG (5, 20, 50 µM) dose-dependently decreased TGF-ß1-induced expression of fibrotic markers collagen 1, α-SMA and fibronectin. In liver fibrosis mouse models induced by CCl4 challenge alone or in combination with HFHC diet, administration of L7DG (40, 150 mg·kg-1·d-1, i.g., for 4 or 8 weeks) dose-dependently attenuated hepatic histopathological injury and collagen accumulation, decreased expression of fibrogenic genes. By conducting target prediction, molecular docking and enzyme activity detection, we identified L7DG as a potent inhibitor of protein tyrosine phosphatase 1B (PTP1B) with an IC50 value of 2.10 µM. Further studies revealed that L7DG inhibited PTP1B activity, up-regulated AMPK phosphorylation and subsequently inhibited HSC activation. This study demonstrates that the phytochemical L7DG may be a potential therapeutic candidate for the treatment of liver fibrosis.

16.
Biochem Biophys Res Commun ; 736: 150515, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39128268

RESUMEN

Heat shock cognate protein 70 (Hsc70/HSPA8) belongs to the Hsp70 family of molecular chaperones. The fundamental functions of Hsp70 family molecular chaperones depend on ATP-dependent allosteric regulation of binding and release of hydrophobic polypeptide substrates. Hsc70 is also involved in various other cellular functions including selective pathways of protein degradation: chaperone-mediated autophagy (CMA) and endosomal microautophagy (eMI), in which Hsc70 recruits substrate proteins containing a KFERQ-like pentapeptide motif from the cytosol to lysosomes and late endosomes, respectively. However, whether the interaction between Hsc70 and the pentapeptide motif is direct or mediated by other molecules has remained unknown. In the present study, we introduced a photo-crosslinker near the KFERQ motif in a CMA/eMI model substrate and successfully detected its crosslinking with Hsc70, revealing the direct interaction between Hsc70 and the KFERQ motif for the first time. In addition, we demonstrated that the loss of the Hsc70 ATPase activity by the D10 N mutation appreciably reduced the crosslinking efficiency. Our present results suggested that the ATP allostery of Hsc70 is involved in the direct interaction of Hsc70 with the KFERQ-like pentapeptide.

17.
Polymers (Basel) ; 16(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39204506

RESUMEN

High-strength concrete (HSC) boasts excellent compressive strength and durability, making it a popular choice in various engineering applications. However, under the impact of high temperatures, HSC tends to crack easily, so it is combined with polyvinyl alcohol fiber (PVA fiber) to explore its engineering application prospect. This paper investigated the physical and mechanical characteristics of HSC reinforced with PVA fibers subjected to different heating temperatures and cooling techniques. The experimental results reveal a correlation between rising temperatures and observable changes in the specimens: a progressively lighter surface hue, an augmented frequency of cracking, and a considerable escalation in the mass loss rate, particularly after the temperature exceeds 400 °C. Regarding mechanical properties, the dynamic elastic modulus and compressive and flexural strength all decrease as the heating temperature increases. As the amount of PVA fiber rises while maintaining a steady temperature, these measurements initially show an increase followed by a decrease. The fiber contents yielding the best compressive and flexural strength are 0.2% and 0.3%, in that order. Considering the influence of cooling methods, water spray cooling has a greater impact on physical and mechanical properties than natural cooling. Furthermore, SEM was employed to scrutinize the microstructure of HSC, enhancing comprehension of the alterations in its physical and mechanical characteristics. The findings of this research offer significant information regarding the high-temperature behavior of HSC, serving as a valuable resource for guiding the design, building, and upkeep of structures that incorporate HSC. Additionally, this study will aid in advancing the progress and utilization of HSC technology.

18.
Hormones (Athens) ; 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39004683

RESUMEN

PURPOSE: To evaluate the prevalence of thyroid dysfunction and its association with possible contributing factors related to diagnosis and treatment in children who received hematopoietic stem cell transplantation (HSCT) in the only national transplant unit in Greece. METHODS: This is an observational, retrospective, single center cohort study that included 194 patients (58.6% boys) who survived for at least 1 year following allogeneic HSCT. Conditioning regimens depended upon diagnosis and protocols active at the time of transplantation. Some patients received irradiation, either central nervous system prophylaxis (n = 20), or total body irradiation (TBI) (n = 8). Thyroid gland evaluation included thyroid-stimulating hormone, free thyroxine, thyroid autoantibodies, and sonogram. Univariate and multivariate logistic models were used to examine the association of the above-mentioned factors with hypothyroidism. RESULTS: The mean age at diagnosis and at bone marrow transplant (BMT) in years was 7.51 ± 0.46 and 7.58 ± 0.36, respectively. The median follow-up time was 4.83 years. Hypothyroidism was detected in 33 cases (17.7%), four of those patients having received TBI. Factors contributing to hypothyroidism as per the multivariate analysis were male sex, [OR: 3.005, 95% CI (1.145-7.890)], irradiation, [OR: 2.876, 95% CI (1.120-7.386)], and years after HSCT [OR: 1.148, 95% CI (1.042-1.266)], while malignancy was identified only in the univariate analysis. The multivariate model presents a good class separation capacity [AUC = 72%, 95% CI (61.4%-82.4%)], Two patients had papillary thyroid cancer, both among children who had received TBI. CONCLUSION: These data highlight the fact that male sex and radiotherapy are two independent factors that lead to increased risk for hypothyroidism. Furthermore, the prevalence of hypothyroidism increases with time post HSCT.

19.
Front Neurol ; 15: 1432608, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38962475

RESUMEN

Purpose: To evaluate the utility of supine roll test (SRT) and alternative positional tests, such as head-shaking test (HST), seated supine positioning test (SSPT), bow and lean test (BLT), and rapid axial roll test (RART) in determining the affected semicircular canal of horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV). Methods: In an observational cohort study, 553 patients diagnosed with HSC-BPPV were divided into five groups in terms of different positional tests received: SRT group (n = 110), HST+ SRT (n = 112), BLT + SRT (n = 114), SSPT+SRT (n = 108) and RART+SRT (n = 109). The same method was used for the last four groups: The patients were first subjected to different alternative positional tests and then to SRT, and the nystagmus was observed separately to determine the affected side. The primary outcomes compared included the accuracy and sensitivity of these tests in the determination of the affected semicircular canal in HSC-BPPV. Results: Patients with nystagmus elicited by positional tests accounted for 84.99% (470/553). The elicitation rate of nystagmus of SRT was lowest, being 77.27% (85/110). The elicitation rate of nystagmus were higher in the test groups than in the control group, and RART+SRT group yielded the highest elicitation rate of nystagmus (95.41%, 104/109). Among the alternative positional tests, RART attained the highest elicitation rate of nystagmus (101/109, 92.66%). Comparison between alternative positional tests and SRT, RART and SRT showed obviously better agreement in determining the affected semicircular canal (85.45%, 96/109) and eliciting nystagmus (95.41%, Kappa = 0.642), but no difference was found in curative effect when the affected side was accurately determined (χ2 = 1.618, p = 0.655). Conclusion: All alternative positional tests are helpful for eliciting nystagmus in patients with HSC-BPPV, and the significant advantages of RART include high-sensitivity in eliciting nystagmus and high accuracy in determining the affected semicircular canal, which provided objective support for the correct diagnosis of HSC-BPPV and the successful reduction of otolith.

20.
Methods Mol Biol ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38967910

RESUMEN

The hematopoietic system constantly produces new blood cells through hematopoiesis, and maintaining this balance is vital for human health. This balance is maintained by self-renewing hematopoietic stem cells (HSCs) and various progenitor cells. Under typical circumstances, HSCs are not abundantly found in peripheral blood; hence, their mobilization from the bone marrow is vital. Hematopoietic growth factors achieve this effectively, enabling mobilization and thus allowing blood sample and thus HSC collection via apheresis. Securing a sufficient supply of HSCs is vital for successful hematopoietic reconstitution and the rapid integration of committed cells. Thus, isolation and expansion of HSCs are crucial for convenient extraction, production of transplantable quantities, genetic modifications for enhanced therapeutic efficacy, and as a source of increased/expanded/synthesized blood cells in vitro. In conclusion, the isolation and expansion of HSCs play pivotal roles in both regenerative medicine and hematology. This protocol describes the isolation of human HSCs by providing an overview of the primary method for isolating human hematopoietic stem cells from apheresis blood samples and sheds light on human HSC studies and developments in research and medicine.

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