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1.
Saudi J Anaesth ; 18(2): 299-301, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38654877

RESUMEN

Atrial fibrillation (AF) is a common arrhythmia requiring effective heart rate (HR) management. Conventional therapies may not always achieve the desired HR control during intraoperative conditions. We present two cases of AF patients in whom dexmedetomidine, an alpha-2 receptor agonist, was utilized during surgery when conventional treatments proved ineffective. In Case 1, a 65-year-old male with multiple comorbidities underwent surgery. Despite receiving intraoperative medications for AF, his HR remained uncontrolled. Dexmedetomidine successfully stabilized his HR without complications. In Case 2, a 75-year-old male with heart disease experienced a sudden HR surge during surgery, which remained uncontrolled despite conventional treatment. Dexmedetomidine effectively managed his HR, ensuring a safer surgical course. While the primary indication of dexmedetomidine is not arrhythmia management, this case report suggests its potential in challenging cases. Further research is needed to explore its therapeutic role in tachyarrhythmia management and establish appropriate dosing strategies.

2.
Exp Mol Med ; 55(12): 2519-2530, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38036736

RESUMEN

Aortic aneurysm is a chronic disease characterized by localized expansion of the aorta, including the ascending aorta, arch, descending aorta, and abdominal aorta. Although aortic aneurysms are generally asymptomatic, they can threaten human health by sudden death due to aortic rupture. Aortic aneurysms are estimated to lead to 150,000 ~ 200,000 deaths per year worldwide. Currently, there are no effective drugs to prevent the growth or rupture of aortic aneurysms; surgical repair or endovascular repair is the only option for treating this condition. The pathogenic mechanisms and therapeutic targets for aortic aneurysms have been examined over the past decade; however, there are unknown pathogenic mechanisms involved in cellular heterogeneity and plasticity, the complexity of the transforming growth factor-ß signaling pathway, inflammation, cell death, intramural neovascularization, and intercellular communication. This review summarizes the latest research findings and current pathogenic mechanisms of aortic aneurysms, which may enhance our understanding of aortic aneurysms.


Asunto(s)
Aneurisma de la Aorta Torácica , Rotura de la Aorta , Humanos , Enfermedad Crónica , Rotura de la Aorta/etiología , Rotura de la Aorta/cirugía , Aorta
4.
Exp Mol Med ; 55(5): 1033-1045, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37121980

RESUMEN

Memory-phenotype (MP) CD4+ T cells are a substantial population of conventional T cells that exist in steady-state mice, yet their immunological roles in autoimmune disease remain unclear. In this work, we unveil a unique phenotype of MP CD4+ T cells determined by analyzing single-cell transcriptomic data and T cell receptor (TCR) repertoires. We found that steady-state MP CD4+ T cells in the spleen were composed of heterogeneous effector subpopulations and existed regardless of germ and food antigen exposure. Distinct subpopulations of MP CD4+ T cells were specifically activated by IL-1 family cytokines and STAT activators, revealing that the cells exerted TCR-independent bystander effector functions similar to innate lymphoid cells. In particular, CCR6high subpopulation of MP CD4+ T cells were major responders to IL-23 and IL-1ß without MOG35-55 antigen reactivity, which gave them pathogenic Th17 characteristics and allowed them to contribute to autoimmune encephalomyelitis. We identified that Bhlhe40 in CCR6high MP CD4+ T cells as a key regulator of GM-CSF expression through IL-23 and IL-1ß signaling, contributing to central nervous system (CNS) pathology in experimental autoimmune encephalomyelitis. Collectively, our findings reveal the clearly distinct effector-like heterogeneity of MP CD4+ T cells in the steady state and indicate that CCR6high MP CD4+ T cells exacerbate autoimmune neuroinflammation via the Bhlhe40/GM-CSF axis in a bystander manner.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Ratones , Animales , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Inmunidad Innata , Enfermedades Neuroinflamatorias , Encefalomielitis Autoinmune Experimental/metabolismo , Células Th17 , Interleucina-23 , Fenotipo , Receptores de Antígenos de Linfocitos T/metabolismo , Linfocitos T CD4-Positivos , Ratones Endogámicos C57BL , Proteínas de Homeodominio/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética
5.
Theranostics ; 13(3): 1076-1090, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36793871

RESUMEN

Precise regulation of kinases and phosphatases is crucial for human metabolic homeostasis. This study aimed to investigate the roles and molecular mechanisms of protein tyrosine phosphatase type IVA1 (PTP4A1) in regulating hepatosteatosis and glucose homeostasis. Method: Ptp4a1-/- mice, adeno-associated virus encoding Ptp4a1 under liver-specific promoter, adenovirus encoding Fgf21, and primary hepatocytes were used to evaluate PTP4A1-mediated regulation in the hepatosteatosis and glucose homeostasis. Glucose tolerance test, insulin tolerance test, 2-deoxyglucose uptake assay, and hyperinsulinemic-euglycemic clamp were performed to estimate glucose homeostasis in mice. The staining, including oil red O, hematoxylin & eosin, and BODIPY, and biochemical analysis for hepatic triglycerides were performed to assess hepatic lipids. Luciferase reporter assays, immunoprecipitation, immunoblots, quantitative real-time polymerase chain reaction, and immunohistochemistry staining were conducted to explore the underlying mechanism. Results: Here, we found that deficiency of PTP4A1 aggravated glucose homeostasis and hepatosteatosis in mice fed a high-fat (HF) diet. Increased lipid accumulation in hepatocytes of Ptp4a1-/- mice reduced the level of glucose transporter 2 on the plasma membrane of hepatocytes leading to a diminution of glucose uptake. PTP4A1 prevented hepatosteatosis by activating the transcription factor cyclic adenosine monophosphate-responsive element-binding protein H (CREBH)/fibroblast growth factor 21 (FGF21) axis. Liver-specific PTP4A1 or systemic FGF21 overexpression in Ptp4a1-/- mice fed an HF diet restored the disorder of hepatosteatosis and glucose homeostasis. Finally, liver-specific PTP4A1 expression ameliorated an HF diet-induced hepatosteatosis and hyperglycemia in wild-type mice. Conclusions: Hepatic PTP4A1 is critical for regulating hepatosteatosis and glucose homeostasis by activating the CREBH/FGF21 axis. Our current study provides a novel function of PTP4A1 in metabolic disorders; hence, modulating PTP4A1 may be a potential therapeutic strategy against hepatosteatosis-related diseases.


Asunto(s)
Dieta Alta en Grasa , Hiperglucemia , Humanos , Animales , Ratones , Dieta Alta en Grasa/efectos adversos , Hígado/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Hiperglucemia/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Glucosa/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Ciclo Celular/metabolismo
6.
Cardiovasc Res ; 119(5): 1265-1278, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-36534975

RESUMEN

AIMS: The nuclear factor-κB (NF-κB) signalling pathway plays a critical role in the pathogenesis of multiple vascular diseases. However, in endothelial cells (ECs), the molecular mechanisms responsible for the negative regulation of the NF-κB pathway are poorly understood. In this study, we investigated a novel role for protein tyrosine phosphatase type IVA1 (PTP4A1) in NF-κB signalling in ECs. METHODS AND RESULTS: In human tissues, human umbilical artery ECs, and mouse models for loss of function and gain of function of PTP4A1, we conducted histological analysis, immunostaining, laser-captured microdissection assay, lentiviral infection, small interfering RNA transfection, quantitative real-time PCR and reverse transcription-PCR, as well as luciferase reporter gene and chromatin immunoprecipitation assays. Short hairpin RNA-mediated knockdown of PTP4A1 and overexpression of PTP4A1 in ECs indicated that PTP4A1 is critical for inhibiting the expression of cell adhesion molecules (CAMs). PTP4A1 increased the transcriptional activity of upstream stimulatory factor 1 (USF1) by dephosphorylating its S309 residue and subsequently inducing the transcription of tumour necrosis factor-alpha-induced protein 3 (TNFAIP3/A20) and the inhibition of NF-κB activity. Studies on Ptp4a1 knockout or transgenic mice demonstrated that PTP4A1 potently regulates the interleukin 1ß-induced expression of CAMs in vivo. In addition, we verified that PTP4A1 deficiency in apolipoprotein E knockout mice exacerbated high-fat high-cholesterol diet-induced atherogenesis with upregulated expression of CAMs. CONCLUSION: Our data indicate that PTP4A1 is a novel negative regulator of vascular inflammation by inducing USF1/A20 axis-mediated NF-κB inactivation. Therefore, the expression and/or activation of PTP4A1 in ECs might be useful for the treatment of vascular inflammatory diseases.


Asunto(s)
Células Endoteliales , FN-kappa B , Vasculitis , Animales , Humanos , Ratones , Proteínas de Ciclo Celular/metabolismo , Células Endoteliales/metabolismo , Inflamación/genética , Inflamación/metabolismo , Proteínas de la Membrana/metabolismo , FN-kappa B/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Transducción de Señal , Factores Estimuladores hacia 5'/metabolismo , Vasculitis/genética , Vasculitis/metabolismo
7.
Exp Mol Med ; 54(8): 1250-1261, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-36028759

RESUMEN

Obesity is a growing global epidemic that can cause serious adverse health consequences, including insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD). Obesity development can be attributed to energy imbalance and metabolic inflexibility. Here, we demonstrated that lack of Kelch-like protein 3 (KLHL3) mitigated the development of obesity, IR, and NAFLD by increasing energy expenditure. KLHL3 mutations in humans cause Gordon's hypertension syndrome; however, the role of KLHL3 in obesity was previously unknown. We examined differences in obesity-related parameters between control and Klhl3-/- mice. A significant decrease in body weight concomitant with fat mass loss and improved IR and NAFLD were observed in Klhl3-/- mice fed a high-fat (HF) diet and aged. KLHL3 deficiency inhibited obesity, IR, and NAFLD by increasing energy expenditure with augmentation of O2 consumption and CO2 production. Delivering dominant-negative (DN) Klhl3 using adeno-associated virus into mice, thereby dominantly expressing DN-KLHL3 in the liver, ameliorated diet-induced obesity, IR, and NAFLD. Finally, adenoviral overexpression of DN-KLHL3, but not wild-type KLHL3, in hepatocytes revealed an energetic phenotype with an increase in the oxygen consumption rate. The present findings demonstrate a novel function of KLHL3 mutation in extrarenal tissues, such as the liver, and may provide a therapeutic target against obesity and obesity-related diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Metabolismo Energético , Resistencia a la Insulina , Proteínas de Microfilamentos , Enfermedad del Hígado Graso no Alcohólico , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Dieta Alta en Grasa/efectos adversos , Metabolismo Energético/genética , Humanos , Resistencia a la Insulina/genética , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Obesidad/genética , Obesidad/metabolismo
8.
Exp Mol Med ; 52(9): 1587-1601, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32929220

RESUMEN

Abdominal aortic aneurysm (AAA) is an inflammatory vascular disease characterized by structural deterioration of the aorta caused by inflammation and oxidative stress, leading to aortic dilatation and rupture. Peroxiredoxin 2 (PRDX2), an antioxidant enzyme, has been reported as a potential negative regulator of inflammatory vascular diseases, and it has been identified as a protein that is increased in patients with ruptured AAA compared to patients with nonruptured AAA. In this study, we demonstrated that PRDX2 was a pivotal factor involved in the inhibition of AAA progression. PRDX2 levels were increased in AAA compared with those in normal aortas in both humans and mice. Ultrasound imaging revealed that the loss of PRDX2 accelerated the development of AAA in the early stages and increased AAA incidence in mice infused with angiotensin II (Ang II). Prdx2-/- mice infused with Ang II exhibited increased aortic dilatation and maximal aortic diameter without a change in blood pressure. Structural deterioration of the aortas from Prdx2-/- mice infused with Ang II was associated with increases in the degradation of elastin, oxidative stress, and intramural thrombi caused by microhemorrhages, immature neovessels, and the activation of matrix metalloproteinases compared to that observed in controls. Moreover, an increase in inflammatory responses, including the production of cell adhesion molecules and the accumulation of inflammatory cells and proinflammatory cytokines due to PRDX2 deficiency, accelerated Ang II-induced AAA progression. Our data confirm that PRDX2 plays a role as a negative regulator of the pathological process of AAA and suggest that increasing PRDX2 activity may be a novel strategy for the prevention and treatment of AAA.


Asunto(s)
Angiotensina II/efectos adversos , Aneurisma de la Aorta Abdominal/etiología , Aneurisma de la Aorta Abdominal/patología , Susceptibilidad a Enfermedades , Peroxirredoxinas/deficiencia , Animales , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Biomarcadores , Biopsia , Moléculas de Adhesión Celular/metabolismo , Citocinas/metabolismo , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Ratones , Ratones Noqueados , Modelos Biológicos , Miocitos del Músculo Liso/metabolismo , Peroxirredoxinas/genética , Especies Reactivas de Oxígeno , Ultrasonografía
9.
Medicine (Baltimore) ; 99(36): e22078, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32899079

RESUMEN

INTRODUCTION: Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disorder characterized by specific pathologic findings and often, but not in all cases, elevated serum IgG4 concentration. Although it can virtually involve every organ system, cases involving the gastrointestinal tract and especially gastric mass lesions have rarely been reported. PATIENT CONCERNS: A 45-year-old man, who was incidentally discovered asymptomatic subepithelial tumor (SET), by endoscopy, on the greater curvature of the upper gastric body, was referred to our hospital for further evaluation. DIAGNOSIS: The patient was postoperatively diagnosed with IgG4-RD by histopathologic results. INTERVENTIONS: The patient underwent laparoscopic wedge resection. OUTCOMES: The patient is presently followed up annually in our clinic and had no problems and showed no signs of recurrence in examination. CONCLUSION: We reported a rare case of IgG4-RD presenting as a gastric SET. The first line treatment of IgG4-RD is glucocorticoid administration. However, because pathologic examination is challenging owing to the lesion location, preoperative diagnosis is difficult and may lead to unnecessary gastric resection. Thus, using alternative preoperative diagnostic methods such as endoscopic ultrasound-guided fine-needle biopsy or the biopsy unroofing technique could spare the patient from unnecessary surgical treatment.


Asunto(s)
Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico , Enfermedad Relacionada con Inmunoglobulina G4/patología , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología
10.
Exp Mol Med ; 52(8): 1255-1263, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32859954

RESUMEN

T cells are the central mediators of both humoral and cellular adaptive immune responses. Highly specific receptor-mediated clonal selection and expansion of T cells assure antigen-specific immunity. In addition, encounters with cognate antigens generate immunological memory, the capacity for long-term, antigen-specific immunity against previously encountered pathogens. However, T-cell receptor (TCR)-independent activation, termed "bystander activation", has also been found. Bystander-activated T cells can respond rapidly and secrete effector cytokines even in the absence of antigen stimulation. Recent studies have rehighlighted the importance of antigen-independent bystander activation of CD4+ T cells in infection clearance and autoimmune pathogenesis, suggesting the existence of a distinct innate-like immunological function performed by conventional T cells. In this review, we discuss the inflammatory mediators that activate bystander CD4+ T cells and the potential physiological roles of these cells during infection, autoimmunity, and cancer.


Asunto(s)
Inmunidad Adaptativa , Efecto Espectador/inmunología , Linfocitos T CD4-Positivos/inmunología , Inmunidad Innata , Animales , Citocinas/metabolismo , Humanos , Activación de Linfocitos/inmunología
11.
Psychiatry Investig ; 16(10): 728-736, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31550876

RESUMEN

OBJECTIVE: Many depressed adolescents do not seek professional help despite there being evidence-based treatments for depression, such as cognitive behavioral therapy or computer-based therapy. To increase professional help-seeking behavior in depressed adolescents, it is necessary to positively change help-seeking attitudes. This study aimed to explore the effect of sub-groups of help-seeking attitudes, gender, and depression level on adolescents' help-seeking intentions and their perceptions of computer-based psychotherapy. METHODS: Participants were 246 adolescents aged 13-18 years recruited from six middle and high schools in South Korea. Measures were self-administered questionnaires, and included the Patient Health Questionnaire-9, the Attitudes Toward Seeking Professional Psychological Help Scale, the Intention to Seek Counseling Inventory, Preferences for Depression Treatment, and the Perceptions of Computerized Therapy Questionnaire. RESULTS: Help-seeking intentions were positively related with female gender and the recognition of the need for help. A higher level of confidence in therapists was related to high preference for computer-based therapy and face-to-face therapy. Adolescents with more severe depression were more likely to prefer pharmacotherapy. The perceptions of computer-based therapy were more positive in male adolescents, and in adolescents with a higher level of confidence in therapists yet a lower level of interpersonal openness. CONCLUSION: To promote adolescents' help-seeking behavior, improvement of the recognition of the need for help is required, especially among male adolescents. Computer-based therapy provides an alternative for male adolescents with high confidence in therapists yet low interpersonal openness. Consideration of the help-seeking attitudes and gender is needed when providing therapeutic intervention to depressed adolescents.

12.
J Cell Biochem ; 120(11): 19186-19201, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31297862

RESUMEN

Rapamycin is well-recognized in the clinical therapeutic intervention for patients with cancer by specifically targeting mammalian target of rapamycin (mTOR) kinase. Rapamycin regulates general autophagy to clear damaged cells. Previously, we identified increased expression of messenger RNA levels of NBR1 (the neighbor of BRCA1 gene; autophagy cargo receptor) in human urothelial cancer (URCa) cells, which were not exhibited in response to rapamycin treatment for cell growth inhibition. Autophagy plays an important role in cellular physiology and offers protection against chemotherapeutic agents as an adaptive response required for maintaining cellular energy. Here, we hypothesized that loss of NBR1 sensitizes human URCa cells to growth inhibition induced by rapamycin treatment, leading to interruption of protective autophagic activation. Also, the potential role of mitochondria in regulating autophagy was tested to clarify the mechanism by which rapamycin induces apoptosis in NBR1-knockdown URCa cells. NBR1-knockdown URCa cells exhibited enhanced sensitivity to rapamycin associated with the suppression of autophagosomal elongation and mitochondrial defects. Loss of NBR1 expression altered the cellular responses to rapamycin treatment, resulting in impaired ATP homeostasis and an increase in reactive oxygen species (ROS). Although rapamycin treatment-induced autophagy by adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in NBR1-knockdown cells, it did not process the conjugated form of LC3B-II after activation by unc-51 like autophagy-activating kinase 1 (ULK1). NBR1-knockdown URCa cells exhibited rather profound mitochondrial dysfunctions in response to rapamycin treatment as evidenced by Δψm collapse, ATP depletion, ROS accumulation, and apoptosis activation. Therefore, our findings provide a rationale for rapamycin treatment of NBR1-knockdown human urothelial cancer through the regulation of autophagy and mitochondrial dysfunction by regulating the AMPK/mTOR signaling pathway, indicating that NBR1 can be a potential therapeutic target of human urothelial cancer.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Mitocondrias/metabolismo , Proteínas de Neoplasias/deficiencia , Sirolimus/farmacología , Neoplasias de la Vejiga Urinaria/metabolismo , Apoptosis/genética , Autofagia/genética , Línea Celular Tumoral , Eliminación de Gen , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Mitocondrias/genética , Mitocondrias/patología , Proteínas de Neoplasias/metabolismo , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología
13.
Sci Rep ; 9(1): 3994, 2019 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-30850686

RESUMEN

Exposure to fine particulate matter (PM) with diameter <2.5 µm (PM2.5) causes epithelium injury and endothelial dysfunction. Primary cilia are sensory organelles that transmit extracellular signals into intracellular biochemical responses and have roles in physiology. To date, there have been no studies investigating whether PM2.5 affects primary cilia in skin. We addressed this in the present study using normal human epidermal keratinocytes (NHEKs) and retinal pigment epithelium (RPE) cells. We found that formation of primary cilium is increased in differentiated NHEKs. However, treatment with PM2.5 blocked increased ciliogenesis in NHEKs and RPE cells. Furthermore, PM2.5 transcriptionally upregulated small proline rich protein 3 (SPRR3) expression by activating c-Jun, and ectopic expression of SPRR3 inhibits suppressed the ciliogenesis. Accordingly, treatment with c-Jun activator (anisomycin) induced SPRR3 expression, whereas the inhibitor (SP600125) recovered the ciliated cells and cilium length in PM2.5-treated cells. Moreover, c-Jun inhibitor suppressed upregulation of SPRR3 in PM2.5-treated cells. Taken together, our finding suggested that PM2.5 inhibits ciliogenesis by increasing SPRR3 expression via c-Jun activation in RPE cells and keratinocytes.


Asunto(s)
Cilios/efectos de los fármacos , Proteínas Ricas en Prolina del Estrato Córneo/metabolismo , Queratinocitos/efectos de los fármacos , Material Particulado/farmacología , Proteínas Proto-Oncogénicas c-jun/metabolismo , Epitelio Pigmentado de la Retina/efectos de los fármacos , Piel/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Cilios/metabolismo , Humanos , Queratinocitos/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Piel/metabolismo , Regulación hacia Arriba/efectos de los fármacos
14.
J Nanobiotechnology ; 17(1): 24, 2019 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-30722792

RESUMEN

BACKGROUND: Silica nanoparticles (SiNPs) are widely used for biosensing and diagnostics, and for the targeted delivery of therapeutic agents. Safety concerns about the biomedical and clinical applications of SiNPs have been raised, necessitating analysis of the effects of their intrinsic properties, such as sizes, shapes, and surface physicochemical characteristics, on human health to minimize risk in biomedical applications. In particular, SiNP size-associated toxicological effects, and the underlying molecular mechanisms in the vascular endothelium remain unclear. This study aimed to elucidate the detailed mechanisms underlying the cellular response to exposure to trace amounts of SiNPs and to determine applicable size criteria for biomedical application. METHODS: To clarify whether these SiNP-mediated cytotoxicity due to induction of apoptosis or necrosis, human ECs were treated with SiNPs of four different non-overlapping sizes under low serum-containing condition, stained with annexin V and propidium iodide (PI), and subjected to flow cytometric analysis (FACS). Two types of cell death mechanisms were assessed in terms of production of reactive oxygen species (ROS), endoplasmic reticulum (ER) stress induction, and autophagy activity. RESULTS: Spherical SiNPs had a diameter of 21.8 nm; this was further increased to 31.4, 42.9, and 56.7 nm. Hence, we investigated these effects in human endothelial cells (ECs) treated with these nanoparticles under overlap- or agglomerate-free conditions. The 20-nm SiNPs, but not SiNPs of other sizes, significantly induced apoptosis and necrosis. Surprisingly, the two types of cell death occurred independently and through different mechanisms. Apoptotic cell death resulted from ROS-mediated ER stress. Furthermore, autophagy-mediated necrotic cell death was induced through the PI3K/AKT/eNOS signaling axis. Together, the present results indicate that SiNPs within a diameter of < 20-nm pose greater risks to cells in terms of cytotoxic effects. CONCLUSION: These data provide novel insights into the size-dependence of the cytotoxic effects of silica nanoparticles and the underlying molecular mechanisms. The findings are expected to inform the applicable size range of SiNPs to ensure their safety in biomedical and clinical applications.


Asunto(s)
Apoptosis/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Nanopartículas/toxicidad , Necrosis/patología , Transducción de Señal/efectos de los fármacos , Dióxido de Silicio , Autofagia/efectos de los fármacos , Células Cultivadas , Medios de Cultivo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Nanopartículas/química , Necrosis/metabolismo , Tamaño de la Partícula , Fosfatidilinositol 3-Quinasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Dióxido de Silicio/química , Dióxido de Silicio/toxicidad
15.
Pharmacol Res ; 139: 325-336, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30472463

RESUMEN

Adipogenesis involved in hypertrophy and hyperplasia of adipocytes is responsible for expanding the mass of adipose tissues in obese individuals. Peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα) are two principal transcription factors induced by delicate signaling pathways, including signal transducer and activator of transcription 5 (STAT5), in adipogenesis. Here, we demonstrated a novel role of ginkgetin, a biflavone from Ginkgo biloba leaves, as a STAT5 inhibitor that blocks the differentiation of preadipocytes into adipocytes. During the differentiation of 3T3-L1 cells, ginkgetin treatment during the first 2 days markedly inhibited the formation of lipid-bearing adipocytes. PPARγ and C/EBPα expression was decreased in 3T3-L1 cells during adipogenesis following ginkgetin treatment, whereas no change was observed in C/EBPß or C/EBPδ expression. Inhibition of PPARγ and C/EBPα expression by ginkgetin occurred through the prevention of STAT5 activation during the initiation phase of adipogenesis. In addition, ginkgetin-mediated the inhibition of adipogenesis was recapitulated in the differentiation of primary preadipocytes. Lastly, we confirmed the inhibitory effects of ginkgetin on the hypertrophy of white adipose tissues from high-fat diet-fed mice. These results indicate that ginkgetin is a potential anti-adipogenesis and anti-obesity drug.


Asunto(s)
Adipogénesis/efectos de los fármacos , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/uso terapéutico , Biflavonoides/farmacología , Biflavonoides/uso terapéutico , Células 3T3-L1 , Animales , Proteína alfa Potenciadora de Unión a CCAAT/genética , Proteína alfa Potenciadora de Unión a CCAAT/metabolismo , Dieta Alta en Grasa , Ginkgo biloba , Masculino , Ratones , Ratones Endogámicos C57BL , PPAR gamma/genética , PPAR gamma/metabolismo , Hojas de la Planta , Transducción de Señal/efectos de los fármacos
16.
Biochem Biophys Res Commun ; 509(1): 167-174, 2019 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-30579607

RESUMEN

PURPOSE: Although Mycobacterium bovis Bacillus Calmette-Guérin (BCG) is the most widely used bladder cancer immunotherapy, innate immune responses involving antimicrobial peptides (AMPs) cause BCG failure and unwanted side effects. Here, we generated genetically modified BCG strains with improved immunotherapeutic effects by adding genes that confer evasion of AMPs. MATERIALS AND METHODS: We constructed recombinant BCG (rBCG) strains expressing Streptococcal inhibitor of complement (Sic), which confers resistance to human α-defensin-1 and cathelicidin, and d-alanyl carrier protein ligase (dltA), which confers resistance to cationic AMPs. Sic and dltA were separately cloned into the pMV306 plasmid and introduced into BCG via electroporation. Then, the efficacy of the rBCGs was tested in a growth inhibition assay using two bladder cancer cell lines (5637, T24). RESULTS: We confirmed the presence of cDNA segments corresponding to the Sic and dltA genes in total mRNA of the rBCG strains containing Sic (rBCG-Sic) and dltA (rBCG-dltA), and these rBCGs showed higher survival against AMPs. The growth inhibitory effects of rBCGs on bladder cancer cells were significantly enhanced compared to those of the parent BCG, and THP-1 migration also increased. After 8 h of infection, the levels of internalization were higher in rBCG-infected bladder cancer cells than in BCG-infected cells, and cells infected with rBCGs showed increased release of antitumor cytokines, such as IL-6/12, TNF-α, and INF-γ, resulting in inhibition of bacterial killing and immune modulation via antimicrobial peptides. CONCLUSIONS: rBCG-Sic and rBCG-dltA can effectively evade BCG-stimulated AMPs, and may be significantly improved immunotherapeutic tools to treat bladder cancer.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/inmunología , Vacuna BCG/genética , Vacunas contra el Cáncer/genética , Mycobacterium bovis/genética , Neoplasias de la Vejiga Urinaria/terapia , Vacuna BCG/inmunología , Vacuna BCG/farmacología , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/farmacología , Línea Celular Tumoral , Humanos , Inmunidad Innata , Inmunoterapia/métodos , Mycobacterium bovis/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/farmacología , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/patología , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/farmacología
17.
J Cell Physiol ; 234(8): 13083-13096, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30549029

RESUMEN

Rapamycin, a mammalian target of rapamycin (mTOR) inhibitor, has significant potential for application in the treatment of urothelial carcinoma (URCa) of the bladder. Previous studies have shown that regulation of the AMP-activated serine/threonine protein kinase (AMPK)-mTOR signaling pathway enhances apoptosis by inducing autophagy or mitophagy in bladder cancer. Alteration of liver kinase B1 (LKB1)-AMPK signaling leads to mitochondrial dysfunction and the accumulation of autophagy-related proteins as a result of mitophagy, resulting in enhanced cell sensitivity to drug treatments. Therefore, we hypothesized that LKB1 deficiency in URCa cells could lead to increased sensitivity to rapamycin by inducing mitochondrial defect-mediated mitophagy. To test this, we established stable LKBI-knockdown URCa cells and analyzed the effects of rapamycin on their growth. Rapamycin enhanced growth inhibition and apoptosis in stable LKB1-knockdown URCa cells and in a xenograft mouse model. In spite of the stable downregulation of LKB1 expression, rapamycin induced AMPK activation in URCa cells, causing loss of the mitochondrial membrane potential, ATP depletion, and ROS accumulation, indicating an alteration of mitochondrial biogenesis. Our findings suggest that the absence of LKB1 can be targeted to induce dysregulated mitochondrial biogenesis by rapamycin treatment in the design of novel therapeutic strategies for bladder cancer.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Células Transicionales/patología , Mitofagia/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Sirolimus/farmacología , Neoplasias de la Vejiga Urinaria/patología , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Carcinoma de Células Transicionales/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Ratones , Ratones Desnudos , Mitofagia/fisiología , Transducción de Señal/efectos de los fármacos , Neoplasias de la Vejiga Urinaria/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Medicine (Baltimore) ; 97(51): e13765, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30572526

RESUMEN

BACKGROUND: Few studies have been conducted on the utility of cervical spine phantoms for practicing cervical procedures. Here, we describe a simple method for creating a cervical spine phantom and investigate whether the use of a gelatin-based phantom is associated with improved proficiency in performing ultrasound-guided cervical medial branch block. METHODS: A cervical spine phantom was prepared using a cervical spine model immersed in a mixture of gelatin and psyllium husk. In total, 27 participants, inexperienced in spinal ultrasonography, were enrolled and allocated to 1 of 2 groups (training group, n = 18; control group, n = 9). All participants were tested (test-1) following an introductory course of basic ultrasonography. Participants in the control group were tested again after 1 week (test-2). Those in the training group received a further individual 3-hour training session, and were tested again after 1 week (test-2). RESULTS: The mean performance score in test-1 was 62.5 ±â€Š10.1 points in the training group and 62.3 ±â€Š4.1 points in the control group [95% confidence interval (95% CI) -5.5 to 5.8; P = .954]. In test-2, the mean score was 86.8 ±â€Š6.5 points and 59.9 ±â€Š4.4 points in the training and control groups, respectively (95% CI 21.9-31.8; P < .001). The mean time required to complete test-1 was 84.6 ±â€Š26.6 seconds in training group and 90.7 ±â€Š43.9 seconds in the control group (95% CI -34.0 to 21.7; P = .653); in test-2, the time required was 56.6 ±â€Š27.9 and 91.2 ±â€Š43.8 seconds (95% CI -63.0 to -6.2; P = .019), respectively. Interobserver reliability showed excellent agreement based on the intraclass correlation coefficient, and moderate to almost perfect agreement by kappa statistics. CONCLUSION: Training using a gelatin-based cervical spine phantom helps novices acquire the skills necessary to perform ultrasound-guided cervical medial branch blocks.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Fantasmas de Imagen , Ultrasonografía Intervencional/métodos , Vértebras Cervicales/cirugía , Competencia Clínica , Humanos , Internado y Residencia , Bloqueo Nervioso/métodos , Estudios Prospectivos
19.
Nutr Res Pract ; 12(3): 191-198, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29854324

RESUMEN

BACKGROUND/OBJECTIVES: Neuroinflammation plays critical role in neurodegenerative disorders, such as Alzheimer's disease (AD). We investigated the effect of three licorice varieties, Glycyrhiza uralensis, G. glabra, and Shinwongam (SW) on a mouse model of inflammation-induced memory and cognitive deficit. MATERIALS/METHODS: C57BL/6 mice were injected with lipopolysaccharide (LPS; 2.5 mg/kg, intraperitoneally) and orally administrated G. uralensis, G. glabra, and SW extract (150 mg/kg/day). SW, a new species of licorice in Korea, was combined with G. uralensis and G. glabra. Behavioral tests, including the T-maze, novel object recognition and Morris water maze, were carried out to assess learning and memory. In addition, the expressions of inflammation-related proteins in brain tissue were measured by western blotting. RESULTS: There was a significant decrease in spatial and objective recognition memory in LPS-induced cognitive impairment group, as measured by the T-maze and novel object recognition test; however, the administration of licorice ameliorated these deficits. In addition, licorice-treated groups exhibited improved learning and memory ability in the Morris water maze. Furthermore, LPS-injected mice had up-regulated pro-inflammatory proteins, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2, interleukin-6, via activation of toll like receptor 4 (TLR4) and nuclear factor-kappa B (NFκB) pathways in the brain. However, these were attenuated by following administration of the three licorice varieties. Interestingly, the SW-administered group showed greater inhibition of iNOS and TLR4 when compared with the other licorice varieties. Furthermore, there was a significant increase in the expression of brain-derived neurotrophic factor (BDNF) in the brain of LPS-induced cognitively impaired mice that were administered licorice, with the greatest effect following SW treatment. CONCLUSIONS: The three licorice varieties ameliorated the inflammation-induced cognitive dysfunction by down-regulating inflammatory proteins and up-regulating BDNF. These results suggest that licorice, in particular SW, could be potential therapeutic agents against cognitive impairment.

20.
Stem Cell Reports ; 11(1): 115-127, 2018 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-29910125

RESUMEN

Pluripotent stem cells (PSCs) represent the most promising clinical source for regenerative medicine. However, given the cellular heterogeneity within cultivation and safety concerns, the development of specific and efficient tools to isolate a pure population and eliminate all residual undifferentiated PSCs from differentiated derivatives is a prerequisite for clinical applications. In this study, we raised a monoclonal antibody and identified its target antigen as desmoglein-2 (DSG2). DSG2 co-localized with human PSC (hPSC)-specific cell surface markers, and its expression was rapidly downregulated upon differentiation. The depletion of DSG2 markedly decreased hPSC proliferation and pluripotency marker expression. In addition, DSG2-negative population in hPSCs exhibited a notable suppression in embryonic body and teratoma formation. The actions of DSG2 in regulating the self-renewal and pluripotency of hPSCs were predominantly exerted through the regulation of ß-catenin/Slug-mediated epithelial-to-mesenchymal transition. Our results demonstrate that DSG2 is a valuable PSC surface marker that is essential for the maintenance of PSC self-renewal.


Asunto(s)
Antígenos de Superficie/metabolismo , Desmogleína 2/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Antígenos de Superficie/genética , Biomarcadores , Diferenciación Celular/genética , Línea Celular , Autorrenovación de las Células/genética , Separación Celular/métodos , Reprogramación Celular/genética , Desmogleína 2/genética , Transición Epitelial-Mesenquimal/genética , Regulación de la Expresión Génica , Humanos , Inmunofenotipificación , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo , beta Catenina/metabolismo
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