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1.
J Hazard Mater ; 456: 131678, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37245364

RESUMEN

Particulate matter ≤ 2.5 µm (PM2.5) poses health risks related to various diseases and infections. However, the interactions between PM2.5 and cells such as uptake and cell responses have not been fully investigated despite advances in bioimaging techniques, because the heterogeneous morphology and composition of PM2.5 make it challenging to employ labeling techniques, such as fluorescence. In this work, we visualized the interaction between PM2.5 and cells using optical diffraction tomography (ODT), which provides quantitative phase images by refractive index distribution. Through ODT analysis, the interactions of PM2.5 with macrophages and epithelial cells, such as intracellular dynamics, uptake, and cellular behavior, were successfully visualized without labeling techniques. ODT analysis clearly shows the behavior of phagocytic macrophages and nonphagocytic epithelial cells for PM2.5. Moreover, ODT analysis could quantitatively compare the accumulation of PM2.5 inside the cells. PM2.5 uptake by macrophages increased substantially over time, but uptake by epithelial cells increased only marginally. Our findings indicate that ODT analysis is a promising alternative approach to visually and quantitatively understanding the interaction of PM2.5 with cells. Therefore, we expect ODT analysis to be employed to investigate the interactions of materials and cells that are difficult to label.


Asunto(s)
Material Particulado , Tomografía Óptica , Material Particulado/toxicidad , Imagenología Tridimensional/métodos , Tomografía Óptica/métodos , Células Epiteliales , Macrófagos
2.
Heliyon ; 9(3): e14179, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36915477

RESUMEN

Particulate matter (PM) contributes to human diseases, particularly lung disease; however, the molecular mechanism of its action is yet to be determined. Herein, we found that prolonged PM exposure induced the cellular senescence of normal lung fibroblasts via a DNA damage-mediated response. This PM-induced senescence (PM-IS) was only observed in lung fibroblasts but not in A549 lung adenocarcinoma cells. Mechanistic analysis revealed that reactive oxygen species (ROS) activate the DNA damage response signaling axis, increasing p53 phosphorylation, ultimately leading to cellular senescence via an increase in p21 expression without affecting the p16-pRB pathway. A549 cells, instead, were resistant to PM-IS due to the PM-induced ROS production suppression. Water-soluble antioxidants, such as vitamin C and N-Acetyl Cysteine, were found to alleviate PM-IS by suppressing ROS production, implying that antioxidants are a promising therapeutic intervention for PM-mediated lung pathogenesis.

3.
Cancer ; 129(3): 405-414, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36451343

RESUMEN

BACKGROUND: This study evaluated whether an addition of bevacizumab to erlotinib improves clinical outcomes in patients with advanced EGFR-mutated non-small cell lung cancer (NSCLC). METHODS: This is an open-label, multicenter, randomized Phase 2 study in South Korea. Chemonaïve patients with Stage IIIB/IV NSCLC with EGFR 19 deletion or L858R mutation were eligible. Asymptomatic brain metastasis (BM) was enrolled without local treatment. Patients received either erlotinib plus bevacizumab or erlotinib. RESULTS: Between December 2016 and March 2019, 127 patients were randomly assigned to receive erlotinib plus bevacizumab (n = 64) or erlotinib (n = 63). Fifty-nine (46.5%) patients had baseline BM. Fewer patients in the erlotinib plus bevacizumab arm received radiotherapy for BM than in the erlotinib arm (10.3% vs. 40.0%). A trend toward longer progression-free survival (PFS) was observed in the erlotinib plus bevacizumab arm compared with the erlotinib alone arm; however, it was not statistically significant (median PFS, 17.5 months vs. 12.4 months; hazard ratio [HR], 0.74; 95% CI, 0.51-1.08; p = .119). The unplanned subgroup analysis showed a longer PFS with erlotinib plus bevacizumab in patients with BM (median PFS, 18.6 months vs. 10.3 months; HR, 0.54; 95% CI, 0.31-0.95; p = .032). Grade 3 or worse adverse events occurred in 56.6% of the erlotinib plus bevacizumab arm and 20.6% of the erlotinib arm. CONCLUSIONS: Although it was not statistically significant, a trend to improvement in PFS was observed in patients with erlotinib plus bevacizumab compared to erlotinib alone. PLAIN LANGUAGE SUMMARY: A randomized Phase 2 study compared erlotinib with or without bevacizumab in previously untreated patients with advanced non-small cell lung cancer with EGFR mutation. The erlotinib plus bevacizumab failed to improve median progression-free survival compared with the erlotinib alone. However, the progression-free survival benefit from erlotinib plus bevacizumab was found in patients with brain metastasis with no severe hemorrhagic adverse effects.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Clorhidrato de Erlotinib , Bevacizumab/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Receptores ErbB/genética , Mutación , Inhibidores de Proteínas Quinasas/efectos adversos , Supervivencia sin Enfermedad
4.
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
5.
BMB Rep ; 56(2): 96-101, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36476270

RESUMEN

Particulate matter is an air pollutant composed of various components, and has adverse effects on the human body. Particulate matter is known to induce cell death by generating an imbalance in the antioxidant system; however, the underlying mechanism has not been elucidated. In the present study, we demonstrated the cytotoxic effects of the size and composition of particulate matter on small intestine cells. We found that particulate matter 2.5 (PM2.5) with extraction ion (EI) components (PM2.5 EI), is more cytotoxic than PM containing only polycyclic aromatic hydrocarbons (PAHs). Additionally, PM-induced cell death is characteristic of ferroptosis, and includes iron accumulation, lipid peroxidation, and reactive oxygen species (ROS) generation. Furthermore, ferroptosis inhibitor as liproxstatin-1 and iron-chelator as deferiprone attenuated cell mortality, lipid peroxidation, iron accumulation, and ROS production after PM2.5 EI treatment in human small intestinal cells. These results suggest that PM2.5 EI may increase ferroptotic-cell death by iron accumulation and ROS generation, and offer a potential therapeutic clue for inflammatory bowel diseases in human small intestinal cells. [BMB Reports 2023; 56(2): 96-101].


Asunto(s)
Antineoplásicos , Ferroptosis , Humanos , Material Particulado , Hierro , Antioxidantes , Especies Reactivas de Oxígeno/metabolismo
6.
Exp Mol Med ; 54(11): 1901-1912, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36352257

RESUMEN

Although many cohort studies have reported that long-term exposure to particulate matter (PM) can cause lung cancer, the molecular mechanisms underlying the PM-induced increase in cancer metastasis remain unclear. To determine whether PM contributes to cancer metastasis, cancer cells were cultured with conditioned medium from PM-treated THP1 cells, and the migration ability of the treated cancer cells was assessed. The key molecules involved were identified using RNA-seq analysis. In addition, metastatic ability was analyzed in vivo by injection of cancer cells into the tail vein and intratracheal injection of PM into the lungs of C57BL/6 mice. We found that PM enhances the expression of heparin-binding EGF-like growth factor (HBEGF) in macrophages, which induces epithelial-to-mesenchymal transition (EMT) in cancer cells, thereby increasing metastasis. Macrophage stimulation by PM results in activation and subsequent nuclear translocation of the aryl hydrocarbon receptor and upregulation of HBEGF. Secreted HBEGF activates EGFR on the cancer cell surface to induce EMT, resulting in increased migration and invasion in vitro and increased metastasis in vivo. Therefore, our study reveals a critical PM-macrophage-cancer cell signaling axis mediating EMT and metastasis and provides an effective therapeutic approach for PM-induced malignancy.


Asunto(s)
Transición Epitelial-Mesenquimal , Factor de Crecimiento Similar a EGF de Unión a Heparina , Macrófagos , Metástasis de la Neoplasia , Material Particulado , Animales , Ratones , Línea Celular Tumoral , Factor de Crecimiento Similar a EGF de Unión a Heparina/metabolismo , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Material Particulado/efectos adversos
7.
BMB Rep ; 55(11): 519-527, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36195564

RESUMEN

Macrophage activation has long been implicated in a myriad of human pathophysiology, particularly in the context of the dysregulated capacities of an unleashing intracellular or/and extracellular inflammatory response. A growing number of studies have functionally coupled the macrophages' inflammatory capacities with dynamic metabolic reprogramming which occurs during activation, albeit the results have been mostly interpreted through classic metabolism point of view; macrophages take advantage of the rewired metabolism as a source of energy and for biosynthetic precursors. However, a specific subset of metabolic products, namely immune-modulatory metabolites, has recently emerged as significant regulatory signals which control inflammatory responses in macrophages and the relevant extracellular milieu. In this review, we introduce recently highlighted immuno-modulatory metabolites, with the aim of understanding their physiological and pathological relevance in the macrophage inflammatory response. [BMB Reports 2022; 55(11): 519-527].


Asunto(s)
Activación de Macrófagos , Macrófagos , Humanos , Activación de Macrófagos/fisiología , Macrófagos/metabolismo , Inmunomodulación , Inflamación/metabolismo
8.
J Gastric Cancer ; 20(3): 337-343, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33024589

RESUMEN

Distal gastrectomy with Billroth I or II reconstruction may cause duodenogastroesophageal reflux (DGER), thereby resulting in digestive or respiratory symptoms. The mainstay of treatment is medication with proton pump inhibitors. However, these drugs may have limited effects in DGER. Laparoscopic fundoplication has been proven to be highly effective in treating gastroesophageal reflux disease (GERD), but it cannot be performed optimally for GERD that develops after gastrectomy. We report the case of a 72-year-old man with a history of distal gastrectomy and Billroth I anastomosis due to early gastric cancer. GERD due to bile reflux occurred after surgery and was refractory to medical therapy. The patient underwent Roux-en-Y conversion from Billroth I gastroduodenostomy and hiatal hernia repair with only cruroplasty. Fundoplication was not performed. His symptoms improved significantly after the surgery. Therefore, laparoscopic hiatal hernia repair and Roux-en-Y conversion can be an effective surgical procedure to treat medically refractory DGER after Billroth I gastrectomy.

9.
Cell Death Dis ; 11(4): 231, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-32286254

RESUMEN

Malignant melanoma is a fatal disease that rapidly spreads to the whole body. Treatments have limited efficiency owing to drug resistance and various side effects. Pseudomonas syringae pv. tomato (Pto) is a model bacterial pathogen capable of systemic infection in plants. Pto injects the effector protein HopQ into the plant cytosol via a type III secretion machinery and suppresses the host immunity. Intriguingly, host plant proteins regulated by HopQ are conserved even in humans and conferred in tumor metastasis. Nevertheless, the potential for HopQ to regulate human cancer metastasis was unknown. In this study, we addressed the suitability of HopQ as a possible drug against melanoma metastasis. In melanoma cells, overexpressed HopQ is phosphorylated and bound to 14-3-3 through its N-terminal domain, resulting in stronger interaction between HopQ and vimentin. The binding of HopQ to vimentin allowed for degradation of vimentin via p62-dependent selective autophagy. Attenuation of vimentin expression by HopQ inhibited melanoma motility and in vivo metastasis. These findings demonstrated that HopQ directly degraded vimentin in melanoma cells and could be applied to an inhibitor of melanoma metastasis.


Asunto(s)
Melanoma/tratamiento farmacológico , Vimentina/uso terapéutico , Animales , Autofagia , Movimiento Celular , Modelos Animales de Enfermedad , Humanos , Masculino , Ratones , Metástasis de la Neoplasia , Fosforilación , Transfección , Vimentina/farmacología
10.
Front Immunol ; 10: 2636, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31781121

RESUMEN

In host defense, it is crucial to maintain the acidity of the macrophage phagosome for effective bacterial clearance. However, the mechanisms governing phagosomal acidification upon exposure to gram-negative bacteria have not been fully elucidated. In this study, we demonstrate that in macrophages exposed to Escherichia coli, the thioredoxin-interacting protein (TXNIP)-associated inflammasome plays a role in pH modulation through the activated caspase-1-mediated inhibition of NADPH oxidase. While there was no difference in early-phase bacterial engulfment between Txnip knockout (KO) macrophages and wild-type (WT) macrophages, Txnip KO macrophages were less efficient at destroying intracellular bacteria in the late phase, and their phagosomes failed to undergo appropriate acidification. These phenomena were associated with reactive oxygen species production and were reversed by treatment with an NADPH oxidase inhibitor or a caspase inhibitor. In line with these results, Txnip KO mice were more susceptible to both intraperitoneally administered E. coli and sepsis induced by cecum ligation and puncture than WT mice. Taken together, this study suggests that the TXNIP-associated inflammasome-caspase-1 axis regulates NADPH oxidase to modulate the pH of the phagosome, controlling bacterial clearance by macrophages.


Asunto(s)
Proteínas Portadoras/inmunología , Caspasa 1/inmunología , Infecciones por Escherichia coli/inmunología , Inflamasomas/inmunología , Macrófagos/inmunología , Fagosomas/química , Tiorredoxinas/inmunología , Animales , Activación Enzimática/inmunología , Escherichia coli/inmunología , Concentración de Iones de Hidrógeno , Macrófagos/química , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasas/inmunología , Fagosomas/inmunología
11.
Exp Mol Med ; 51(10): 1-13, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31615975

RESUMEN

The disruption of the retinal pigment epithelium (RPE), for example, through oxidative damage, is a common factor underlying age-related macular degeneration (AMD). Aberrant autophagy also contributes to AMD pathology, as autophagy maintains RPE homeostasis to ensure blood-retinal barrier (BRB) integrity and protect photoreceptors. Thioredoxin-interacting protein (TXNIP) promotes cellular oxidative stress by inhibiting thioredoxin reducing capacity and is in turn inversely regulated by reactive oxygen species levels; however, its role in oxidative stress-induced RPE cell dysfunction and the mechanistic link between TXNIP and autophagy are largely unknown. Here, we observed that TXNIP expression was rapidly downregulated in RPE cells under oxidative stress and that RPE cell proliferation was decreased. TXNIP knockdown demonstrated that the suppression of proliferation resulted from TXNIP depletion-induced autophagic flux, causing increased p53 activation via nuclear localization, which in turn enhanced AMPK phosphorylation and activation. Moreover, TXNIP downregulation further negatively impacted BRB integrity by disrupting RPE cell tight junctions and enhancing cell motility by phosphorylating, and thereby activating, Src kinase. Finally, we also revealed that TXNIP knockdown upregulated HIF-1α, leading to the enhanced secretion of VEGF from RPE cells and the stimulation of angiogenesis in cocultured human retinal microvascular endothelial cells. This suggests that the exposure of RPE cells to sustained oxidative stress may promote choroidal neovascularization, another AMD pathology. Together, these findings reveal three distinct mechanisms by which TXNIP downregulation disrupts RPE cell function and thereby exacerbates AMD pathogenesis. Accordingly, reinforcing or restoring BRB integrity by targeting TXNIP may serve as an effective therapeutic strategy for preventing or attenuating photoreceptor damage in AMD.


Asunto(s)
Barrera Hematorretinal/metabolismo , Proteínas Portadoras/genética , Degeneración Macular/genética , Estrés Oxidativo/genética , Animales , Autofagia/genética , Barrera Hematorretinal/patología , Movimiento Celular/genética , Regulación de la Expresión Génica/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Degeneración Macular/patología , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Retina/metabolismo , Retina/patología , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Tiorredoxinas/genética , Uniones Estrechas/genética , Uniones Estrechas/patología , Proteína p53 Supresora de Tumor/genética , Factor A de Crecimiento Endotelial Vascular/genética
12.
Cancer Res ; 79(16): 4135-4148, 2019 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-31209060

RESUMEN

Snail is a key regulator of epithelial-mesenchymal transition (EMT), which is a major step in tumor metastasis. Although the induction of Snail transcription precedes EMT, posttranslational regulation, especially phosphorylation of Snail, is critical for determining Snail protein levels or stability, subcellular localization, and the ability to induce EMT. To date, several kinases are known that enhance the stability of Snail by preventing its ubiquitination; however, the molecular mechanism(s) underlying this are still unclear. Here, we identified p38 MAPK as a crucial posttranslational regulator that enhances the stability of Snail. p38 directly phosphorylated Snail at Ser107, and this effectively suppressed DYRK2-mediated Ser104 phosphorylation, which is critical for GSK3ß-dependent Snail phosphorylation and ßTrCP-mediated Snail ubiquitination and degradation. Importantly, functional studies and analysis of clinical samples established a crucial role for the p38-Snail axis in regulating ovarian cancer EMT and metastasis. These results indicate the potential therapeutic value of targeting the p38-Snail axis in ovarian cancer. SIGNIFICANCE: These findings identify p38 MAPK as a novel regulator of Snail protein stability and potential therapeutic target in ovarian cancer.


Asunto(s)
Glucógeno Sintasa Quinasa 3 beta/metabolismo , Neoplasias Ováricas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Factores de Transcripción de la Familia Snail/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Línea Celular Tumoral , Transición Epitelial-Mesenquimal , Femenino , Humanos , Ratones Endogámicos BALB C , Simulación del Acoplamiento Molecular , Neoplasias Ováricas/patología , Fosforilación , Proteínas Serina-Treonina Quinasas/química , Proteínas Tirosina Quinasas/química , Serina/metabolismo , Factores de Transcripción de la Familia Snail/química , Factores de Transcripción de la Familia Snail/genética , Ubiquitinación , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas con Repetición de beta-Transducina/metabolismo , Quinasas DyrK
13.
Toxins (Basel) ; 9(10)2017 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-29027919

RESUMEN

Shiga toxins (Stxs) produced by Shiga toxin-producing bacteria Shigella dysenteriae serotype 1 and select serotypes of Escherichia coli are the most potent known virulence factors in the pathogenesis of hemorrhagic colitis progressing to potentially fatal systemic complications such as acute renal failure, blindness and neurological abnormalities. Although numerous studies have defined apoptotic responses to Shiga toxin type 1 (Stx1) or Shiga toxin type 2 (Stx2) in a variety of cell types, the potential significance of Stx-induced apoptosis of photoreceptor and pigmented cells of the eye following intoxication is unknown. We explored the use of immortalized human retinal pigment epithelial (RPE) cells as an in vitro model of Stx-induced retinal damage. To the best of our knowledge, this study is the first report that intoxication of RPE cells with Stxs activates both apoptotic cell death signaling and the endoplasmic reticulum (ER) stress response. Using live-cell imaging analysis, fluorescently labeled Stx1 or Stx2 were internalized and routed to the RPE cell endoplasmic reticulum. RPE cells were significantly sensitive to wild type Stxs by 72 h, while the cells survived challenge with enzymatically deficient mutant toxins (Stx1A- or Stx2A-). Upon exposure to purified Stxs, RPE cells showed activation of a caspase-dependent apoptotic program involving a reduction of mitochondrial transmembrane potential (Δψm), increased activation of ER stress sensors IRE1, PERK and ATF6, and overexpression CHOP and DR5. Finally, we demonstrated that treatment of RPE cells with Stxs resulted in the activation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK), suggesting that the ribotoxic stress response may be triggered. Collectively, these data support the involvement of Stx-induced apoptosis in ocular complications of intoxication. The evaluation of apoptotic responses to Stxs by cells isolated from multiple organs may reveal unique functional patterns of the cytotoxic actions of these toxins in the systemic complications that follow ingestion of toxin-producing bacteria.


Asunto(s)
Células Epiteliales/efectos de los fármacos , Toxina Shiga I/toxicidad , Toxina Shiga II/toxicidad , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Línea Celular , Estrés del Retículo Endoplásmico/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/fisiología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Epitelio Pigmentado de la Retina/citología
14.
J Endocrinol ; 235(3): 223-235, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29042402

RESUMEN

Healthy expansion of adipose tissue maintains metabolic homeostasis by storing excess chemical energy in increased fat mass. The STAT5-PPAR gamma pathway reportedly regulates adipocyte differentiation, lipid metabolism and adipogenesis. Ginsenoside Rg3 is one of the diverse groups of steroidal saponins, the major active components of ginseng, which have demonstrated pharmacological properties. In this study, we evaluated the therapeutic effects of ginsenoside Rg3 under pathological conditions in vitro and in vivo We examined the effects of ginsenoside Rg3 on glucose level, insulin sensitivity and lipogenesis in high-fat diet-fed C57BL/6 mice. Ginsenoside Rg3 was also applied to the pre-adipocyte cell line 3T3-L1 to assess the impact on lipogenesis. Ginsenoside Rg3 reduced epididymal white adipose tissue (eWAT) size and hepatic steatosis, and the amount of triglycerides (TGs) in both eWAT and liver. Similar to the murine model, Rg3-treated 3T3-L1 cells showed a reduction in lipid accumulation and amount of total TGs. Ginsenoside Rg3 regulates the expression of PPAR gamma though STAT5 in vitro and in vivo According to our results, lipid metabolism-related genes were downregulated in the high-fat mice and 3T3-L1 cell line. Rg3 shows potential for the amelioration of obesity-induced pathology, acting though STAT5-PPAR gamma to facilitate the healthy functioning of adipose tissue. This is the first report of evidence that obesity-induced insulin resistance and lipotoxicity can be treated with ginsenoside Rg3, which acts though the STAT5-PPAR gamma pathway in vivo and in vitro.


Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Hígado Graso/prevención & control , Ginsenósidos/farmacología , PPAR gamma/metabolismo , Factor de Transcripción STAT5/metabolismo , Células 3T3-L1 , Adipocitos/citología , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipogénesis/efectos de los fármacos , Adipogénesis/genética , Tejido Adiposo Blanco/metabolismo , Animales , Antineoplásicos Fitogénicos/farmacología , Glucemia/metabolismo , Western Blotting , Dieta Alta en Grasa/efectos adversos , Epidídimo/efectos de los fármacos , Epidídimo/metabolismo , Hígado Graso/etiología , Hígado Graso/genética , Regulación de la Expresión Génica/efectos de los fármacos , Resistencia a la Insulina , Lipogénesis/efectos de los fármacos , Lipogénesis/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/etiología , Obesidad/genética , Obesidad/prevención & control , PPAR gamma/genética , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción STAT5/genética , Triglicéridos/metabolismo
15.
Acta Biomater ; 46: 191-203, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27640918

RESUMEN

Despite the rapid expansion of the biomedical applications of graphene oxide (GO), safety issues related to GO, particularly with regard to its effects on vascular endothelial cells (ECs), have been poorly evaluated. To explore possible GO-mediated vasculature cytotoxicity and determine lateral GO size relevance, we constructed four types of GO: micrometer-sized GO (MGO; 1089.9±135.3nm), submicrometer-sized GO (SGO; 390.2±51.4nm), nanometer-sized GO (NGO; 65.5±16.3nm), and graphene quantum dots (GQDs). All types but GQD showed a significant decrease in cellular viability in a dose-dependent manner. Notably, SGO or NGO, but not MGO, potently induced apoptosis while causing no detectable necrosis. Subsequently, SGO or NGO markedly induced autophagy through a process dependent on the c-Jun N-terminal kinase (JNK)-mediated phosphorylation of B-cell lymphoma 2 (Bcl-2), leading to the dissociation of Beclin-1 from the Beclin-1-Bcl-2 complex. Autophagy suppression attenuated the SGO- or NGO-induced apoptotic cell death of ECs, suggesting that SGO- or NGO-induced cytotoxicity is associated with autophagy. Moreover, SGO or NGO significantly induced increased intracellular calcium ion (Ca2+) levels. Intracellular Ca2+ chelation with BAPTA-AM significantly attenuated microtubule-associated protein 1A/1B-light chain 3-II accumulation and JNK phosphorylation, resulting in reduced autophagy. Furthermore, we found that SGO or NGO induced Ca2+ release from the endoplasmic reticulum through the PLC ß3/IP3/IP3R signaling axis. These results elucidate the mechanism underlying the size-dependent cytotoxicity of GOs in the vasculature and may facilitate the development of a safer biomedical application of GOs. STATEMENT OF SIGNIFICANCE: Graphene oxide (GO) have received considerable attention with respect to their utilization in biomedical applications. However, GO-related safety issues concerning human vasculature are very limited. In this manuscript, we report for the first time the differential size-related biological effects of GOs on endothelial cells (ECs). Notably, Subnanometer- and nanometersized GOs induce apoptotic death in ECs via autophagy activation. We propose a molecular mechanism for the GO-induced autophagic cell death through the PLCß3/IP3/Ca2+/JNK signaling axis. Our findings could be provide a better understanding of the GO sizedependent cytotoxicity in vasculature and facilitate the future development of safer biomedical applications of GOs.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Grafito/farmacología , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/enzimología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Adenilato Quinasa/metabolismo , Beclina-1/metabolismo , Calcio/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Espacio Intracelular/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Microscopía de Fuerza Atómica , Modelos Biológicos , Nanopartículas , Tamaño de la Partícula , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo
16.
BMB Rep ; 49(6): 349-54, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27222124

RESUMEN

The archaeon Sulfolobus solfataricus P1 carboxylesterase is a thermostable enzyme with a molecular mass of 33.5 kDa belonging to the mammalian hormone-sensitive lipase (HSL) family. In our previous study, we purified the enzyme and suggested the expected amino acids related to its catalysis by chemical modification and a sequence homology search. For further validating these amino acids in this study, we modified them using site-directed mutagenesis and examined the activity of the mutant enzymes using spectrophotometric analysis and then estimated by homology modeling and fluorescence analysis. As a result, it was identified that Ser151, Asp244, and His274 consist of a catalytic triad, and Gly80, Gly81, and Ala152 compose an oxyanion hole of the enzyme. In addition, it was also determined that the cysteine residues are located near the active site or at the positions inducing any conformational changes of the enzyme by their replacement with serine residues. [BMB Reports 2016; 49(6): 349-354].


Asunto(s)
Aminoácidos/metabolismo , Biocatálisis , Carboxilesterasa/química , Carboxilesterasa/metabolismo , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Sulfolobus solfataricus/enzimología , Secuencia de Aminoácidos , Carboxilesterasa/genética , Cisteína/metabolismo , Fluorescencia , Proteínas Mutantes/química , Proteínas Mutantes/aislamiento & purificación , Mutación/genética , Plásmidos/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología Estructural de Proteína , Relación Estructura-Actividad
17.
Cancer Res Treat ; 48(2): 465-72, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26044164

RESUMEN

PURPOSE: Paclitaxel (P) and gemcitabine (G) are clinically synergistic in small cell lung cancer (SCLC). We evaluated the efficacy of PG as a salvage treatment for SCLC patients whose disease progressed after a platinum-containing regimen. MATERIALS AND METHODS: Eligibility included histologically confirmed SCLC, one dimensionally measurable disease, Eastern Cooperative Oncology Group performance status 0-2, and progressive disease after platinum-based chemotherapy. Treatment consisted of P (80 mg/m(2)) and G (1,000 mg/m(2)) on days 1 and 8 of each cycle of 21 days until disease progression. RESULTS: Thirty-three patients seen between December 2005 and February 2009 were selected into this study. Thirty patients (91%) had received irinotecan-platinum, and three had received etoposide-platinum. Sixteen patients (49%) had a treatment-free interval of less than 3 months. The overall response rate was 30.3% (29.4% in sensitive relapse and 31.3% in refractory relapse). The median time to progression was 12.0 weeks and median overall survival (OS) 31.0 weeks, with a 1-year OS rate of 30.3%. Toxicities were moderate and manageable with 18.2% grade (G) 4 neutropenia, 24.2% G3 thrombocytopenia, 6.1% G3 sensory neuropathy, and 3% G3 asthenia. One patient developed febrile neutropenia. CONCLUSION: Second-line paclitaxel and gemcitabine were well-tolerated and moderately active in SCLC patients previously treated with platinum-based chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Paclitaxel , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/patología
18.
Biochim Biophys Acta ; 1850(7): 1389-96, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25857772

RESUMEN

BACKGROUND: Melanogenesis, a process producing the pigment melanin in human skin, eyes and hair, is a major physiological response against various environmental stresses, in particular exposure to ultraviolet radiation, and its pathway is regulated by a key enzyme, tyrosinase. In this study, we evaluated the effects of ephedrannins A and B, which are polyphenols from the roots of Ephedra sinica, commonly used in herbalism in oriental countries, on mushroom tyrosinase and melanogenesis in B16F10 melanoma cells. METHODS: Their effects on mushroom tyrosinase were determined via kinetic studies using a spectrophotometric analysis and those on melanin and tyrosinase production in melanoma cells treated with α-MSH (melanin stimulating hormone) were examined using PCR and ELISA. RESULTS: Both ephedrannins A and B exhibited concentration-dependent inhibitory effects on L-tyrosine oxidation by mushroom tyrosinase, and the inhibition mechanism was competitive and reversible with L-tyrosine as the substrate. In addition, melanin production in melanoma cells was also suppressed in a concentration-dependent manner by ephedrannins A and B without significant effects on cell proliferation at the concentrations tested. Both compounds showed inhibitory effects on melanin production by suppressing the transcription of tyrosinase in the cells. CONCLUSION: Both compounds exhibited significant inhibitory effects, but the inhibition by ephedrannin B was much more effective than that by ephedrannin A. Both ephedrannins A and B may be good candidates for a whitening agent for skin. GENERAL SIGNIFICANCE: This is the first report that describes effective inhibition of melanin production by ephedrannins A and B isolated from Ephedra roots.


Asunto(s)
Ephedra sinica/química , Melaninas/biosíntesis , Monofenol Monooxigenasa/metabolismo , Raíces de Plantas/química , Proantocianidinas/farmacología , Animales , Biocatálisis/efectos de los fármacos , Western Blotting , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Cinética , Ratones , Estructura Molecular , Monofenol Monooxigenasa/genética , Extractos Vegetales/farmacología , Proantocianidinas/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad por Sustrato , Tirosina/metabolismo
19.
Aging Clin Exp Res ; 27(2): 179-86, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24997614

RESUMEN

BACKGROUND AND AIMS: Decline in muscle endurance and strength as well as attenuated cardiac function with aging not only leads to overall physical function decline but also has a close relationship with cardiovascular disease occurrence. This study examined the effects of an 8-week combined training program (i.e., consisting of both aerobic and resistance training) on body composition, isokinetic strength, and cardiovascular disease (CVD) risk factors in older women. METHODS: Nineteen women, aged 65-75 years, were randomly assigned to either a combined training (CT, n = 9) or an aerobic training (AT, n = 10) group. Body composition and isokinetic strength were assessed before and after the exercise program. Blood samples were collected to identify CVD risk factors. RESULTS: At the end of the training program, body mass, body fat mass, percent body fat, and body mass index decreased significantly and lean mass increased significantly in the CT group compared with those in the AT group (p < 0.05). Isokinetic strength was also significantly greater in the CT group than in the AT group (p < 0.05). In addition, the C-reactive protein level was significantly lower in the CT group than in the AT group, whereas interleukin-6, tumor necrosis factor-α, and total cholesterol levels were significantly lower in both groups (p < 0.05). CONCLUSIONS: An 8-week combined exercise program benefits body composition, especially lean mass, and positively affects isokinetic strength and CVD risk factors. Therefore, increasing lean mass and strength by continuously participating in a combined exercise program may be an effective treatment for preventing and improving CVD in older women.


Asunto(s)
Composición Corporal , Enfermedades Cardiovasculares/etiología , Fuerza Muscular , Entrenamiento de Fuerza , Anciano , Proteína C-Reactiva/análisis , Citocinas/sangre , Femenino , Humanos , Factores de Riesgo
20.
Lung Cancer ; 85(2): 161-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24857785

RESUMEN

PURPOSE: To investigate the clinical utility of targeted next-generation sequencing (NGS) for predicting the responsiveness to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) therapy, we compared the efficacy with conventional sequencing in never-smokers with lung adenocarcinoma (NSLAs). PATIENTS AND METHODS: We obtained DNA from 48 NSLAs who received gefitinib or erlotinib for their recurrent disease after surgery. Sanger sequencing and peptide nucleic acid clamp polymerase chain reaction (PCR) were used to analyze EGFR, KRAS, BRAF, and PIK3CA mutations. We analyzed ALK, RET, and ROS1 rearrangements by fluorescent in situ hybridization or reverse transcriptase-PCR and quantitative real-time PCR. After molecular screening, Ion Torrent NGS was performed in 31 cases harboring only EGFR exon 19 deletions (19DEL), an L858R mutation, or none of the above mutations. RESULTS: The 31 samples were divided into four groups: (1) responders to EGFR-TKIs with only 19DEL or L858R (n=15); (2) primary resistance to EGFR-TKI with only 19DEL or L858R (n=4); (3) primary resistance to EGFR-TKI without any mutations (n=8); (4) responders to EGFR-TKI without any mutations (n=4). With NGS, all conventionally detected mutations were confirmed except for one L858R in group 2. Additional uncovered predictive mutations with NGS included one PIK3CA E542K in group 2, two KRAS (G12V and G12D), one PIK3CA E542K, one concomitant PIK3CA and EGFR L858R in group 3, and one EGFR 19DEL in group 4. CONCLUSIONS: Targeted NGS provided a more accurate and clinically useful molecular classification of NSLAs. It may improve the efficacy of EGFR-TKI therapy in lung cancer.


Asunto(s)
Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Receptores ErbB/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma del Pulmón , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Biología Computacional , Análisis Mutacional de ADN , Receptores ErbB/antagonistas & inhibidores , Femenino , Genes ras , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Mutación , Proteínas Nucleares/genética , Pronóstico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/genética , Reproducibilidad de los Resultados , Factores de Transcripción/genética , Resultado del Tratamiento
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