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2.
World Neurosurg ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39128613

RESUMO

OBJECTIVE: In this study, we aimed to investigate whether multi-segment fusion or fusion-to-sacrum increases sacroiliac joint (SIJ) pathology compared with single-segment fusion or a non-fused sacrum. METHODS: This study included 116 patients who underwent lumbar or lumbosacral fusion and were followed up for 2 years. The patients were classified into single-segment fusion (n = 46) and multi-segment fusion (more than two levels, n = 70) groups and then reclassified into the non-fused sacrum (n = 68) and fusion-to-sacrum groups (n = 48). Preoperative and postoperative radiographs were used to evaluate radiographic parameters, and computed tomography (CT) was used to evaluate SIJ degeneration. Low back pain (LBP) was assessed using a visual analog scale (VAS, 0-10). Baseline and postoperative values were compared using a paired sample t-test. RESULTS: LBP VAS scores significantly differed at 6 months (single-segment fusion, 3.04±1.88; multi-segment fusion, 4.83±2.33; P < 0.001) and 2 years postoperatively (single-segment fusion, 3.3±2.2; multi-segment fusion, 4.78±2.59; P = 0.094). There was no significant difference in SIJ degeneration, as assessed by CT scan, between the 2 surgical groups: 14 (30%) and 19 (27%) patients in the single-segment and multi-segment (P = 0.701) fusion groups, respectively. The LBP VAS scale showed comparable differences at 1 (non-fused sacrum, 3±2.18; fusion-to-sacrum, 3.74±2.28; P = 0.090) and 2 years postoperatively (non-fused sacrum, 3.29±2.01; fusion-to-sacrum, 4.66±2.71; P = 0.095). CT scan revealed that 18 (26%) and 15 (31%) patients in the non-fused sacrum and fusion-to-sacrum groups, respectively, developed SIJ arthritis; however, there was no significant intergroup difference (P = 0.574). CONCLUSIONS: SIJ degeneration occurs independent of the number of fused segments or sacrum involvement.

3.
Ecotoxicol Environ Saf ; 280: 116544, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38838463

RESUMO

Benzyl butyl phthalate (BBP) is a widely used plasticizer that poses various potential health hazards. Although BBP has been extensively studied, the direct mechanism underlying its toxicity in male germ cells remains unclear. Therefore, we investigated BBP-mediated male germ cell toxicity in GC-1 spermatogonia (spg), a differentiated mouse male germ cell line. This study investigated the impact of BBP on reactive oxygen species (ROS) generation, apoptosis, and autophagy regulation, as well as potential protective measures against BBP-induced toxicity. A marked dose-dependent decrease in GC-1 spg cell proliferation was observed following treatment with BBP at 12.5 µM. Exposure to 50 µM BBP, approximating the IC50 of 53.9 µM, markedly increased cellular ROS generation and instigated apoptosis, as evidenced by augmented protein levels of both intrinsic and extrinsic apoptosis-related markers. An amount of 50 µM BBP induced marked upregulation of autophagy regulator proteins, p38 MAPK, and extracellular signal-regulated kinase and substantially downregulated the phosphorylation of key kinases involved in regulating cell proliferation, including phosphoinositide 3-kinase, protein kinase B, mammalian target of rapamycin (mTOR), c-Jun N-terminal kinase. The triple combination of N-acetylcysteine, parthenolide, and 3-methyladenine markedly restored cell proliferation, decreased BBP-induced apoptosis and autophagy, and restored mTOR phosphorylation. This study provides new insights into BBP-induced male germ cell toxicity and highlights the therapeutic potential of the triple inhibitors in mitigating BBP toxicity.


Assuntos
Acetilcisteína , Adenina , Apoptose , Autofagia , Proliferação de Células , Ácidos Ftálicos , Espécies Reativas de Oxigênio , Sesquiterpenos , Masculino , Animais , Camundongos , Ácidos Ftálicos/toxicidade , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/farmacologia , Acetilcisteína/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Adenina/toxicidade , Proliferação de Células/efeitos dos fármacos , Linhagem Celular , Plastificantes/toxicidade , Espermatogônias/efeitos dos fármacos
4.
Environ Toxicol Pharmacol ; 108: 104466, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38759847

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in consumer products, raising concerns about their impact on human health. This study investigates the effects of TiO2 NPs on male germ cells while focusing on cell proliferation inhibition and underlying mechanisms. This was done by utilizing mouse GC-1 spermatogonia cells, an immortalized spermatogonia cell line. TiO2 NPs induced a concentration-dependent proliferation inhibition with increased reactive oxygen species (ROS) generation. Notably, TiO2 NPs induced autophagy and decreased ERK phosphorylation. Treatment with the ROS inhibitor N-Acetyl-l-cysteine (NAC) alleviated TiO2 NPs-induced autophagy, restored ERK phosphorylation, and promoted cell proliferation. These findings call attention to the reproductive risks posed by TiO2 NPs while also highlighting NAC as a possible protective agent against reproductive toxins.


Assuntos
Acetilcisteína , Autofagia , Proliferação de Células , Nanopartículas Metálicas , Espécies Reativas de Oxigênio , Titânio , Titânio/toxicidade , Masculino , Autofagia/efeitos dos fármacos , Animais , Acetilcisteína/farmacologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Espermatogônias/efeitos dos fármacos , Nanopartículas/toxicidade
5.
Global Spine J ; : 21925682241254800, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741363

RESUMO

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare the incidence of adjacent segmental pathology (ASP) following minimally invasive (MI) vs open transforaminal lumbar interbody fusion (TLIF) and to identify factors linked to ASP requiring reoperation. METHODS: This retrospective study reviewed the outcomes of patients who underwent MI-TLIF or open TLIF. Radiographic ASP (RASP) was evaluated using X-ray imaging to distinguish between degenerative changes, spondylolisthesis, and instability in the adjacent spinal segment. Clinical ASP (CASP) was assessed with the visual analog scale score for leg and back pain and the Oswestry disability index. Patient data were collected 1, 2, 5, and 10 years postoperatively. The timing and frequency of ASP reoperation were analyzed. RESULTS: Five years postoperatively, the RASP rate was 35.23% and 45.95% in the MI-TLIF and open TLIF groups. The frequency of CASP differed significantly between the MI-TLIF and open TLIF groups at 1 year postoperatively. The rates of RASP, CASP, and ASP necessitating reoperation were not significantly different 10 years postoperatively. Cranial facet violation significantly affected ASP in both groups. In the open TLIF group, preoperative adjacent segment disc degeneration significantly influenced ASP. CONCLUSION: The RASP rate at 5 years postoperatively and the CASP rate at 1 year postoperatively differed significantly between groups. There was no difference in the rate of ASP requiring reoperation. Cranial facet violation is a crucial driving factor for ASP after both surgical procedures.

6.
Food Chem Toxicol ; 188: 114652, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583502

RESUMO

The estrogen-like effect of bisphenol A (BPA) disrupting the maintenance of functional male germ cells is associated with male sub-fertility. This study investigated toxicity of male germ cells induced by four bisphenol analogs: BPA, BPAF, BPF, and BPS. The investigation of bisphenol analogs' impact on male germ cells included assessing proliferation, apoptosis induction, and the capacity to generate reactive oxygen species (ROS) in GC-1 spermatogonia (spg) cells, specifically type B spermatogonia. Additionally, the therapeutic potential and protective effects of N-Acetyl Cysteine (NAC) and NF-κB inhibitor parthenolide was evaluated. In comparison to BPA, BPF and BPS, BPAF exhibited the most pronounced adverse effect in GC-1 spg cell proliferation. This effect was characterized by pronounced inhibition of phosphorylation of PI3K, AKT, and mTOR, along with increased release of cytochrome c and subsequent cleavages of caspase 3, caspase 7, and poly (ADP-ribose) polymerase. Both NAC and parthenolide were effective reducing cellular ROS induced by BPAF. However, only NAC demonstrated a substantial recovery in proliferation, accompanied by a significant reduction in cytochrome c release and cleaved PARP. These results suggest that NAC supplementation may play an effective therapeutic role in countering germ cell toxicity induced by environmental pollutants with robust oxidative stress-generating capacity.


Assuntos
Acetilcisteína , Apoptose , Compostos Benzidrílicos , Proliferação de Células , Fenóis , Espécies Reativas de Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Masculino , Fenóis/toxicidade , Animais , Compostos Benzidrílicos/toxicidade , Acetilcisteína/farmacologia , Camundongos , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Sesquiterpenos/farmacologia , Linhagem Celular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espermatogônias/efeitos dos fármacos , Espermatogônias/metabolismo , Serina-Treonina Quinases TOR/metabolismo , NF-kappa B/metabolismo
7.
Hum Mol Genet ; 33(2): 110-121, 2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-37769355

RESUMO

The c.453delC (p.Thr152Profs*14) frameshift mutation in KCNH2 is associated with an elevated risk of Long QT syndrome (LQTS) and fatal arrhythmia. Nevertheless, the loss-of-function mechanism underlying this mutation remains unexplored and necessitates an understanding of electrophysiology. To gain insight into the mechanism of the LQT phenotype, we conducted whole-cell patch-clamp and immunoblot assays, utilizing both a heterologous expression system and patient-derived induced pluripotent stem cell-cardiomyocytes (iPSC-CMs) with 453delC-KCNH2. We also explored the site of translational reinitiation by employing LC/MS mass spectrometry. Contrary to the previous assumption of early termination of translation, the findings of this study indicate that the 453delC-KCNH2 leads to an N-terminally truncated hERG channel, a potential from a non-canonical start codon, with diminished expression and reduced current (IhERG). The co-expression with wildtype KCNH2 produced heteromeric hERG channel with mild dominant-negative effect. Additionally, the heterozygote patient-derived iPSC-CMs exhibited prolonged action potential duration and reduced IhERG, which was ameliorated with the use of a hERG activator, PD-118057. The results of our study offer novel insights into the mechanisms involved in congenital LQTS associated with the 453delC mutation of KCNH2. The mutant results in the formation of less functional N-terminal-truncated channels with reduced amount of membrane expression. A hERG activator is capable of correcting abnormalities in both the heterologous expression system and patient-derived iPSC-CMs.


Assuntos
Células-Tronco Pluripotentes Induzidas , Síndrome do QT Longo , Humanos , Miócitos Cardíacos/metabolismo , Mutação da Fase de Leitura , Células-Tronco Pluripotentes Induzidas/metabolismo , Canais de Potássio Éter-A-Go-Go/genética , Canal de Potássio ERG1/genética , Canal de Potássio ERG1/metabolismo , Heterozigoto , Mutação , Síndrome do QT Longo/genética , Síndrome do QT Longo/metabolismo
8.
Cell Prolif ; 56(2): e13366, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36478274

RESUMO

Hemogenic endothelium (HE) plays a pivotal and inevitable role in haematopoiesis and can generate all blood and endothelial lineage cells in the aorta-gonad-mesonephros of mouse embryos. Whether definitive HE can prospectively isolate pure HE from human pluripotent stem cells that can spontaneously differentiate into heterogeneous cells remains unknown. Here, we identified and validated a CD34dim subpopulation with hemogenic potential. We also purified CD34 cells with a CXCR4- CD73- phenotype as a definitive HE population that generated haematopoietic stem cells and lymphocytes. The frequency of CXCR4- CD73- CD34dim was evidently increased by bone morphogenetic protein 4, and purified HE cells differentiated into haematopoietic cells with myeloid and T lymphoid lineages including Vδ2+ subset of γ/δ T cells. We developed a simple method to purify HE cells that were enriched in CD34dim cells. We uncovered an initial step in differentiating haematopoietic lineage cells that could be applied to basic and translational investigations into regenerative medicine.


Assuntos
Hemangioblastos , Células-Tronco Pluripotentes , Animais , Camundongos , Humanos , Hemangioblastos/metabolismo , Proteína Morfogenética Óssea 4/farmacologia , Proteína Morfogenética Óssea 4/metabolismo , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Antígenos CD34/metabolismo , Diferenciação Celular , Hematopoese , Linhagem da Célula
9.
Sci Rep ; 12(1): 20035, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414738

RESUMO

A non-neoplastic mass posterior to the dens is termed a retro-odontoid mass (R-OM). This retrospective study evaluated radiographic and clinical outcomes and R-OM changes after upper cervical spine surgery. This study included 69 patients who underwent upper cervical spine surgery, including atlantoaxial fusion, occipitocervical fusion, or decompression. All patients underwent preoperative magnetic resonance imaging (MRI). Six-month follow-up MRI examinations were performed in 30 patients who had preoperative R-OMs. Radiographic outcomes of the anterior and posterior atlantodental intervals were measured using X-rays and computed tomography. The R-OM and space available for the cord (SAC) were measured using MRI. Clinical outcomes were evaluated using neck and arm pain visual analog scales, the Japanese Orthopedic Association score, the neck disability index, and the patient-reported subjective improvement rate. The anterior atlantodental interval decreased, while the posterior atlantodental interval and SAC increased postoperatively. Among the clinical outcomes, the neck and arm pain and the neck disability index decreased postoperatively, while the Japanese Orthopedic Association score increased. All clinical and radiographic outcomes improved postoperatively. The R-OM either decreased in size or disappeared after fusion surgery in all cases, except in one patient who underwent decompression surgery. In conclusion, stabilization through fusion surgery is essential for treating R-OM.


Assuntos
Articulação Atlantoaxial , Processo Odontoide , Humanos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Vértebras Cervicais/patologia , Estudos Retrospectivos , Dor/patologia
10.
J Biol Chem ; 298(9): 102289, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35868563

RESUMO

The protein product of the CDKN1A gene, p21, has been extensively characterized as a negative regulator of the cell cycle. Nevertheless, it is clear that p21 has manifold complex and context-dependent roles that can be either tumor suppressive or oncogenic. Most well studied as a transcriptional target of the p53 tumor suppressor protein, there are other means by which p21 levels can be regulated. In this study, we show that pharmacological inhibition or siRNA-mediated reduction of O-GlcNAc transferase (OGT), the enzyme responsible for glycosylation of intracellular proteins, increases expression of p21 in both p53-dependent and p53-independent manners in nontransformed and cancer cells. In cells harboring WT p53, we demonstrate that inhibition of OGT leads to p53-mediated transactivation of CDKN1A, while in cells that do not express p53, inhibiting OGT leads to increased p21 protein stabilization. p21 is normally degraded by the ubiquitin-proteasome system following ubiquitination by, among others, the E3 ligase Skp-Cullin-F-box complex; however, in this case, we show that blocking OGT causes impairment of the Skp-Cullin-F-box ubiquitin complex as a result of disruption of the FoxM1 transcription factor-mediated induction of Skp2 expression. In either setting, we conclude that p21 levels induced by OGT inhibition correlate with cell cycle arrest and decreased cancer cell proliferation.


Assuntos
Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21 , Proteína Forkhead Box M1 , N-Acetilglucosaminiltransferases , Proteínas Quinases Associadas a Fase S , Proteína Supressora de Tumor p53 , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Proteínas Culina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteína Forkhead Box M1/metabolismo , Humanos , N-Acetilglucosaminiltransferases/antagonistas & inibidores , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Estabilidade Proteica , RNA Interferente Pequeno , Proteínas Quinases Associadas a Fase S/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina/metabolismo
11.
Sci Adv ; 8(8): eabj6621, 2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35213232

RESUMO

Direct lineage conversion holds great promise in the regenerative medicine field for restoring damaged tissues using functionally engineered counterparts. However, current methods of direct lineage conversion, even those using virus-mediated transgenic expression of tumorigenic factors, are extremely inefficient (~25%). Thus, advanced methodologies capable of revolutionizing efficiency and addressing safety concerns are key to clinical translation of these technologies. Here, we propose an extracellular vesicle (EV)-guided, nonviral, direct lineage conversion strategy to enhance transdifferentiation of fibroblasts to induced cardiomyocyte-like cells (iCMs). The resulting iCMs have typical cardiac Ca2+ transients and electrophysiological features and exhibit global gene expression profiles similar to those of cardiomyocytes. This is the first demonstration of the use of EVs derived from embryonic stem cells undergoing cardiac differentiation as biomimetic tools to induce cardiac reprogramming with extremely high efficiency (>60%), establishing a general, more readily accessible platform for generating a variety of specialized somatic cells through direct lineage conversion.

12.
Yonsei Med J ; 63(3): 265-271, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35184429

RESUMO

PURPOSE: To investigate the radiologic and clinical outcomes of direct internal fixation for unstable atlas fractures. MATERIALS AND METHODS: This retrospective study included 12 patients with unstable atlas fractures surgically treated using C1 lateral mass screws, rods, and transverse connector constructs. Nine lateral mass fractures with transverse atlantal ligament (TAL) avulsion injury and three 4-part fractures with TAL injury (two avulsion injuries, one TAL substance tear) were treated. Radiologic outcomes included the anterior atlantodental interval (AADI) in flexion and extension cervical spine lateral radiographs at 6 months and 1 year after treatment. CT was also performed to visualize bony healing of the atlas at 6 months and 1 year. Visual Analog Scale (VAS) scores for neck pain, Neck Disability Index (NDI) values, and cervical range of motion (flexion, extension, and rotation) were recorded at 6 months after surgery. RESULTS: The mean postoperative extension and flexion AADIs were 3.79±1.56 (mean±SD) and 3.13±1.01 mm, respectively. Then mean AADI was 3.42±1.34 and 3.33±1.24 mm at 6 months and 1 year after surgery, respectively. At 1 year after surgery, 11 patients showed bony healing of the atlas on CT images. Only one patient underwent revision surgery 8 months after primary surgery due to nonunion and instability findings. The mean VAS score for neck pain was 0.92±0.99, and the mean NDI value was 8.08±5.70. CONCLUSION: C1 motion-preserving direct internal fixation technique results in good reduction and stabilization of unstable atlas fractures. This technique allows for the preservation of craniocervical and atlantoaxial motion.


Assuntos
Atlas Cervical , Fraturas da Coluna Vertebral , Parafusos Ósseos , Atlas Cervical/diagnóstico por imagem , Atlas Cervical/lesões , Atlas Cervical/cirurgia , Fixação Interna de Fraturas/métodos , Humanos , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia
13.
Clin Transl Sci ; 15(2): 501-513, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34719115

RESUMO

On October 2020, the US Food and Drug Administration (FDA) approved remdesivir as the first drug for the treatment of coronavirus disease 2019 (COVID-19), increasing remdesivir prescriptions worldwide. However, potential cardiovascular (CV) toxicities associated with remdesivir remain unknown. We aimed to characterize the CV adverse drug reactions (ADRs) associated with remdesivir using VigiBase, an individual case safety report database of the World Health Organization (WHO). Disproportionality analyses of CV-ADRs associated with remdesivir were performed using reported odds ratios and information components. We conducted in vitro experiments using cardiomyocytes derived from human pluripotent stem cell cardiomyocytes (hPSC-CMs) to confirm cardiotoxicity of remdesivir. To distinguish drug-induced CV-ADRs from COVID-19 effects, we restricted analyses to patients with COVID-19 and found that, after adjusting for multiple confounders, cardiac arrest (adjusted odds ratio [aOR]: 1.88, 95% confidence interval [CI]: 1.08-3.29), bradycardia (aOR: 2.09, 95% CI: 1.24-3.53), and hypotension (aOR: 1.67, 95% CI: 1.03-2.73) were associated with remdesivir. In vitro data demonstrated that remdesivir reduced the cell viability of hPSC-CMs in time- and dose-dependent manners. Physicians should be aware of potential CV consequences following remdesivir use and implement adequate CV monitoring to maintain a tolerable safety margin.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/efeitos adversos , Tratamento Farmacológico da COVID-19 , Doenças Cardiovasculares/induzido quimicamente , Farmacovigilância , SARS-CoV-2 , Monofosfato de Adenosina/efeitos adversos , Alanina/efeitos adversos , Bases de Dados Factuais , Humanos , Miócitos Cardíacos/efeitos dos fármacos , Estudos Retrospectivos , Organização Mundial da Saúde
14.
Biomaterials ; 266: 120472, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33120201

RESUMO

Human embryonic stem cells-derived endothelial progenitor cells (hEPCs) were utilized as cell therapeutics for the treatment of ischemic diseases. However, in vivo tracking of hEPCs for predicting their therapeutic efficacy is very difficult. Herein, we developed bioorthogonal labeling strategy of hEPCs that could non-invasively track them after transplantation in hind limb ischemia models. First, hEPCs were treated with tetraacylated N-azidomannosamine (Ac4ManNAz) for generating unnatural azide groups on the hEPCs surface. Second, near-infrared fluorescence (NIRF) dye, Cy5, conjugated dibenzocylooctyne (DBCO-Cy5) was chemically conjugated to the azide groups on the hEPC surface via copper-free click chemistry, resulting Cy5-hEPCs. The bioorthogonally labeled Cy5-hEPCs showed strong NIRF signal without cytotoxicity and functional perturbation in tubular formation, oxygen consumption and paracrine effect of hEPCs in vitro. In hind limb ischemia models, the distribution and migration of transplanted Cy5-hEPCs were successfully monitored via fluorescence molecular tomography (FMT) for 28 days. Notably, blood reperfusion and therapeutic neovascularization effects were significantly correlated with the initial transplantation forms of Cy5-hEPCs such as 'condensed round shape' and 'spread shape' in the ischemic lesion. The condensed transplanted Cy5-hEPCs substantially increased the therapeutic efficacy of hind limb ischemia, compared to that of spread Cy5-hEPCs. Therefore, our new stem cell labeling strategy can be used to predict therapeutic efficacy in hind limb ischemia and it can be applied a potential application in developing cell therapeutics for regenerative medicine.


Assuntos
Células Progenitoras Endoteliais , Animais , Química Click , Modelos Animais de Doenças , Membro Posterior , Humanos , Isquemia/diagnóstico por imagem , Isquemia/terapia , Neovascularização Fisiológica , Células-Tronco , Tomografia
15.
Antiviral Res ; 184: 104955, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33091434

RESUMO

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is considered as the most significant global public health crisis of the century. Several drug candidates have been suggested as potential therapeutic options for COVID-19, including remdesivir, currently the only authorized drug for use under an Emergency Use Authorization. However, there is only limited information regarding the safety profiles of the proposed drugs, in particular drug-induced cardiotoxicity. Here, we evaluated the antiviral activity and cardiotoxicity of remdesivir using cardiomyocytes-derived from human pluripotent stem cells (hPSC-CMs) as an alternative source of human primary cardiomyocytes (CMs). In this study, remdesivir exhibited up to 60-fold higher antiviral activity in hPSC-CMs compared to Vero E6 cells; however, it also induced moderate cardiotoxicity in these cells. To gain further insight into the drug-induced arrhythmogenic risk, we assessed QT interval prolongation and automaticity of remdesivir-treated hPSC-CMs using a multielectrode array (MEA). As a result, the data indicated a potential risk of QT prolongation when remdesivir is used at concentrations higher than the estimated peak plasma concentration. Therefore, we conclude that close monitoring of the electrocardiographic/QT interval should be advised in SARS-CoV-2-infected patients under remdesivir medication, in particular individuals with pre-existing heart conditions.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/farmacologia , COVID-19/virologia , Miócitos Cardíacos/virologia , Células-Tronco Pluripotentes/citologia , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/farmacologia , Alanina/farmacologia , Amidas/farmacologia , Animais , Antimaláricos/farmacologia , COVID-19/complicações , Chlorocebus aethiops , Cloroquina/farmacologia , Eletrocardiografia , Citometria de Fluxo , Cardiopatias/complicações , Humanos , Hidroxicloroquina/farmacologia , Microscopia de Fluorescência , Miócitos Cardíacos/efeitos dos fármacos , Células-Tronco Pluripotentes/virologia , Pirazinas/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Vero , Ensaio de Placa Viral , Tratamento Farmacológico da COVID-19
16.
Biomedicines ; 8(11)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33121085

RESUMO

Despite recent advances in clinical stem cell therapy applications based on human pluripotent stem cells (hPSCs), potential teratoma formation due to the presence of residual undifferentiated hPSCs remains a serious risk factor that challenges widespread clinical application. To overcome this risk, a variety of approaches have been developed to eliminate the remaining undifferentiated hPSCs via selective cell death induction. Our study seeks to identify natural flavonoids that are more potent than quercetin (QC), to selectively induce hPSC death. Upon screening in-house flavonoids, luteolin (LUT) is found to be more potent than QC to eliminate hPSCs in a p53-dependent manner, but not hPSC-derived smooth muscle cells or perivascular progenitor cells. Particularly, treating human embryonic stem cell (hESC)-derived cardiomyocytes with LUT efficiently eliminates the residual hESCs and only results in marginal effects on cardiomyocyte (CM) functions, as determined by calcium influx. Considering the technical limitations of isolating CMs due to a lack of exclusive surface markers at the end of differentiation, LUT treatment is a promising approach to minimize teratoma formation risk.

17.
PLoS One ; 15(5): e0232899, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392240

RESUMO

Various nanopatterning techniques have been developed to improve cell proliferation and differentiation efficiency. As we previously reported, nanopillars and pores are able to sustain human pluripotent stem cells and differentiate pancreatic cells. From this, the nanoscale patterns would be effective environment for the co-culturing of epithelial and mesenchymal cell types. Interestingly, the nanopatterning selectively reduced the proliferative rate of mesenchymal cells while increasing the expression of adhesion protein in epithelial type cells. Additionally, co-cultured cells on the nanopatterning were not negatively affected in terms of cell function metabolic ability or cell survival. This is in contrast to conventional co-culturing methods such as ultraviolet or chemical treatments. The nanopatterning appears to be an effective environment for mesenchymal co-cultures with typically low proliferative rates cells such as astrocytes, neurons, melanocytes, and fibroblasts without using potentially damaging treatments.


Assuntos
Técnicas de Cocultura/instrumentação , Células Epiteliais , Células-Tronco Mesenquimais , Nanoestruturas , Animais , Adesão Celular , Proliferação de Células , Sobrevivência Celular , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Propriedades de Superfície
18.
Genes Dev ; 34(7-8): 526-543, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32079652

RESUMO

MDM2 and MDMX, negative regulators of the tumor suppressor p53, can work separately and as a heteromeric complex to restrain p53's functions. MDM2 also has pro-oncogenic roles in cells, tissues, and animals that are independent of p53. There is less information available about p53-independent roles of MDMX or the MDM2-MDMX complex. We found that MDM2 and MDMX facilitate ferroptosis in cells with or without p53. Using small molecules, RNA interference reagents, and mutant forms of MDMX, we found that MDM2 and MDMX, likely working in part as a complex, normally facilitate ferroptotic death. We observed that MDM2 and MDMX alter the lipid profile of cells to favor ferroptosis. Inhibition of MDM2 or MDMX leads to increased levels of FSP1 protein and a consequent increase in the levels of coenzyme Q10, an endogenous lipophilic antioxidant. This suggests that MDM2 and MDMX normally prevent cells from mounting an adequate defense against lipid peroxidation and thereby promote ferroptosis. Moreover, we found that PPARα activity is essential for MDM2 and MDMX to promote ferroptosis, suggesting that the MDM2-MDMX complex regulates lipids through altering PPARα activity. These findings reveal the complexity of cellular responses to MDM2 and MDMX and suggest that MDM2-MDMX inhibition might be useful for preventing degenerative diseases involving ferroptosis. Furthermore, they suggest that MDM2/MDMX amplification may predict sensitivity of some cancers to ferroptosis inducers.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Ferroptose/genética , Metabolismo dos Lipídeos/genética , PPAR alfa/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Proteínas de Ciclo Celular/genética , Glioblastoma/fisiopatologia , Células HCT116 , Humanos , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/genética , Interferência de RNA , Ratos , Proteína Supressora de Tumor p53/metabolismo , Ubiquinona/análogos & derivados , Ubiquinona/metabolismo
19.
Curr Eye Res ; 45(9): 1136-1143, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31951764

RESUMO

PURPOSE: Epstein-Barr virus is a γ-herpes virus that infects primary B cells and can transform infected cells into immortalized lymphoblastoid cell lines (LCL). The role of EBV in malignancies such as Burkitt's lymphoma and nasopharyngeal carcinoma is well understood, however, its role in EBV-infected retinal cells remains poorly understood. Therefore, we investigated the effect of EBV on the growth of retinal cells. METHODS: Previously, we established and reported a cell line model to address the relationship between EBV infection and retinal cell proliferation that used adult retinal pigment epithelium (ARPE-19) and EBV infection. To determine the effect of EBV on ARPE-19 cells, cell death was measured by propidium iodine/annexin V staining and reactive oxygen species (ROS) were measured by FACS, and protein expression was evaluated using western blot analysis. Also, downregulation of LMP1 and NADPH oxidase 4 (NOX4) expression was accomplished using siRNA technology. RESULTS: We found that ROS were dramatically increased in EBV-infected ARPE19 cells (APRE19/EBV) relative to the parental cell line. Additionally, the expression level of NOX4, a main source of ROS, was upregulated by EBV infection. Interestingly, downregulation of LMP1, one of the EBV viral onco-proteins, completely decreased EBV-induced ROS accumulation and the upregulation of NOX4. Treatment with APX-115A, a pan-NOX inhibitor, induced apoptotic cell death of only the EBV-infected ARPE19 cells but not the parental cell line. Pretreatment with z-VAD, a pan-caspase inhibitor, inhibited NOX inhibitor-induced cell death in ARPE19/EBV cells. Furthermore, APX-115A-induced cell death mediated the activation of JNK and ERK. Finally, we confirmed the expression level of NOX4, and APX-115A induced cell death of EBV-infected human primary retina epithelial cells and the activation of JNK and ERK. CONCLUSION: Taken together, these our results suggest that APX-115A could be a therapeutic agent for treating EBV-infected retinal cells or diseases by inhibiting LMP1-NOX4-ROS signaling.


Assuntos
Apoptose/efeitos dos fármacos , Caspases/metabolismo , Herpesvirus Humano 4/fisiologia , NADPH Oxidase 4/metabolismo , Pirazóis/farmacologia , Piridinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/patologia , Western Blotting , Linhagem Celular , Proliferação de Células , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Humanos , NADPH Oxidases/antagonistas & inibidores , Epitélio Pigmentado da Retina/enzimologia , Epitélio Pigmentado da Retina/virologia , Transdução de Sinais/efeitos dos fármacos
20.
Biomaterials ; 225: 119534, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31590118

RESUMO

3D culture of stem cells can improve therapeutic effects. However, there is limited research on how to deliver cultured stem cell spheroids to the desired target. Here, we developed lotus seedpod-inspired hydrogel (LoSH) containing microwells for culture and delivery of stem cell spheroids. Human adipose-derived stem cells (hADSCs) inside the square microwells (200 or 400 µm in width with various depths) spontaneously formed spheroids with high viability (94.08 ±â€¯1.56%), and fibronectins conjugated to the hydrogel successfully gripped the spheroids, similar to the funiculus gripping seeds in the lotus seedpod. The spheroids slightly bound to the LoSH surface at 37 °C were detached by the expansion of LoSH at lower temperature of 4 °C. After spheroid formation, LoSH was placed on the target substrate upside-down, expanded at 4 °C for 10 min, and removed from the target. As a result, the spheroids within the microwell were successfully transferred to the target substrate with high transfer efficiency (93.78 ±â€¯2.30%). A delivery of spheroids from LoSH to full-thickness murine skin wound with chimney model showed significant enhancement of the number of SMA-positive vessels at day 21 compared to the group received the same number of spheroids by injection. Together, our findings demonstrate LoSH as a one-step platform that can culture and deliver spheroids to a large target area, which will be useful for various biomedical applications.


Assuntos
Materiais Biomiméticos/farmacologia , Técnicas de Cultura de Células/métodos , Hidrogéis/farmacologia , Lotus/química , Sementes/química , Esferoides Celulares/transplante , Células-Tronco/citologia , Animais , Adesão Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Camundongos , Regeneração/efeitos dos fármacos , Pele/patologia , Esferoides Celulares/citologia , Esferoides Celulares/efeitos dos fármacos , Transplante de Células-Tronco , Células-Tronco/efeitos dos fármacos
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