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1.
Nature ; 616(7957): 563-573, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37046094

RESUMEN

B cells are frequently found in the margins of solid tumours as organized follicles in ectopic lymphoid organs called tertiary lymphoid structures (TLS)1,2. Although TLS have been found to correlate with improved patient survival and response to immune checkpoint blockade (ICB), the underlying mechanisms of this association remain elusive1,2. Here we investigate lung-resident B cell responses in patients from the TRACERx 421 (Tracking Non-Small-Cell Lung Cancer Evolution Through Therapy) and other lung cancer cohorts, and in a recently established immunogenic mouse model for lung adenocarcinoma3. We find that both human and mouse lung adenocarcinomas elicit local germinal centre responses and tumour-binding antibodies, and further identify endogenous retrovirus (ERV) envelope glycoproteins as a dominant anti-tumour antibody target. ERV-targeting B cell responses are amplified by ICB in both humans and mice, and by targeted inhibition of KRAS(G12C) in the mouse model. ERV-reactive antibodies exert anti-tumour activity that extends survival in the mouse model, and ERV expression predicts the outcome of ICB in human lung adenocarcinoma. Finally, we find that effective immunotherapy in the mouse model requires CXCL13-dependent TLS formation. Conversely, therapeutic CXCL13 treatment potentiates anti-tumour immunity and synergizes with ICB. Our findings provide a possible mechanistic basis for the association of TLS with immunotherapy response.


Asunto(s)
Retrovirus Endógenos , Inmunoterapia , Neoplasias Pulmonares , Animales , Humanos , Ratones , Adenocarcinoma del Pulmón/inmunología , Adenocarcinoma del Pulmón/terapia , Adenocarcinoma del Pulmón/virología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Carcinoma de Pulmón de Células no Pequeñas/virología , Modelos Animales de Enfermedad , Retrovirus Endógenos/inmunología , Inmunoterapia/métodos , Pulmón/inmunología , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/virología , Microambiente Tumoral , Linfocitos B/inmunología , Estudios de Cohortes , Anticuerpos/inmunología , Anticuerpos/uso terapéutico
2.
Mol Cancer ; 23(1): 87, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702773

RESUMEN

BACKGROUND: Intratumoral heterogeneity (ITH) and tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) play important roles in tumor evolution and patient outcomes. However, the precise characterization of diverse cell populations and their crosstalk associated with PDAC progression and metastasis is still challenging. METHODS: We performed single-cell RNA sequencing (scRNA-seq) of treatment-naïve primary PDAC samples with and without paired liver metastasis samples to understand the interplay between ITH and TME in the PDAC evolution and its clinical associations. RESULTS: scRNA-seq analysis revealed that even a small proportion (22%) of basal-like malignant ductal cells could lead to poor chemotherapy response and patient survival and that epithelial-mesenchymal transition programs were largely subtype-specific. The clonal homogeneity significantly increased with more prevalent and pronounced copy number gains of oncogenes, such as KRAS and ETV1, and losses of tumor suppressor genes, such as SMAD2 and MAP2K4, along PDAC progression and metastasis. Moreover, diverse immune cell populations, including naïve SELLhi regulatory T cells (Tregs) and activated TIGIThi Tregs, contributed to shaping immunosuppressive TMEs of PDAC through cellular interactions with malignant ductal cells in PDAC evolution. Importantly, the proportion of basal-like ductal cells negatively correlated with that of immunoreactive cell populations, such as cytotoxic T cells, but positively correlated with that of immunosuppressive cell populations, such as Tregs. CONCLUSION: We uncover that the proportion of basal-like subtype is a key determinant for chemotherapy response and patient outcome, and that PDAC clonally evolves with subtype-specific dosage changes of cancer-associated genes by forming immunosuppressive microenvironments in its progression and metastasis.


Asunto(s)
Evolución Clonal , Neoplasias Hepáticas , Neoplasias Pancreáticas , Análisis de la Célula Individual , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Evolución Clonal/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Transcriptoma , Transición Epitelial-Mesenquimal/genética , Biomarcadores de Tumor/genética , Pronóstico , Adenocarcinoma/genética , Adenocarcinoma/patología , Masculino , Femenino , Análisis de Expresión Génica de una Sola Célula
3.
Gastrointest Endosc ; 100(1): 85-96.e9, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38447660

RESUMEN

BACKGROUND AND AIMS: Pancreatic ductal adenocarcinoma (PDAC) has the worst survival rate among tumors. At the time of diagnosis, more than 80% of PDACs are considered to be surgically unresectable, and there is an unmet need for treatment options in these inoperable PDACs. This study aimed to establish a patient-derived organoid (PDO) platform from EUS-guided fine-needle biopsy (EUS-FNB) collected at diagnosis and to determine its clinical applicability for the timely treatment of unresectable PDAC. METHODS: Patients with suspected PDAC were prospectively enrolled at the Samsung Medical Center from 2015 to 2019. PDAC tissues were acquired by means of EUS-FNB to establish PDAC PDOs, which were comprehensively analyzed for histology, genomic sequencing, and high-throughput screening (HTS) drug sensitivity test. RESULTS: PDAC PDOs were established with a success rate of 83.2% (94/113). It took approximately 3 weeks from acquiring minimal EUS-FNB specimens to generating sufficient PDAC PDOs for the simultaneous HTS drug sensitivity test and genomic sequencing. The high concordance between PDAC tissues and matched PDOs was confirmed, and whole-exome sequencing revealed the increased detection of genetic alterations in PDOs compared with EUS-FNB tissues. The HTS drug sensitivity test showed clinical correlation between the ex vivo PDO response and the actual chemotherapeutic response of the study patients in the real world (13 out of 15 cases). In addition, whole-transcriptome sequencing identified candidate genes associated with nab-paclitaxel resistance, such as ITGB7, ANPEP, and ST3GAL1. CONCLUSIONS: This PDAC PDO platform allows several therapeutic drugs to be tested within a short time window and opens the possibility for timely personalized medicine as a "patient avatar model" in clinical practice.


Asunto(s)
Carcinoma Ductal Pancreático , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Organoides , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/patología , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Organoides/patología , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Estudios Prospectivos , Anciano de 80 o más Años , Adulto , Medicina de Precisión/métodos , Avatar , Albúminas
4.
J Transl Med ; 21(1): 730, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37848935

RESUMEN

BACKGROUND: Lysosomes are closely linked to autophagic activity, which plays a vital role in pancreatic ductal adenocarcinoma (PDAC) biology. The survival of PDAC patients is still poor, and the identification of novel genetic factors for prognosis and treatment is highly required to prevent PDAC-related deaths. This study investigated the germline variants related to lysosomal dysfunction in patients with PDAC and to analyze whether they contribute to the development of PDAC. METHODS: The germline putative pathogenic variants (PPV) in genes involved in lysosomal storage disease (LSD) was compared between patients with PDAC (n = 418) and healthy controls (n = 845) using targeted panel and whole-exome sequencing. Furthermore, pancreatic organoids from wild-type and KrasG12D mice were used to evaluate the effect of lysosomal dysfunction on PDAC development. RNA sequencing (RNA-seq) analysis was performed with established PDAC patient-derived organoids (PDOs) according to the PPV status. RESULTS: The PPV in LSD-related genes was higher in patients with PDAC than in healthy controls (8.13 vs. 4.26%, Log2 OR = 1.65, P = 3.08 × 10-3). The PPV carriers of LSD-related genes with PDAC were significantly younger than the non-carriers (mean age 61.5 vs. 65.3 years, P = 0.031). We further studied a variant of the lysosomal enzyme, galactosylceramidase (GALC), which was the most frequently detected LSD variant in our cohort. Autophagolysosomal activity was hampered when GALC was downregulated, which was accompanied by paradoxically elevated autophagic flux. Furthermore, the number of proliferating Ki-67+ cells increased significantly in pancreatic organoids derived from Galc knockout KrasG12D mice. Moreover, GALC PPV carriers tended to show drug resistance in both PDAC cell line and PDAC PDO, and RNA-seq analysis revealed that various metabolism and gene repair pathways were upregulated in PDAC PDOs harboring a GALC variant. CONCLUSIONS: Genetically defined lysosomal dysfunction is frequently observed in patients with young-onset PDAC. This might contribute to PDAC development by altering metabolism and impairing autophagolysosomal activity, which could be potentially implicated in therapeutic applications for PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Ratones , Animales , Persona de Mediana Edad , Proteínas Proto-Oncogénicas p21(ras) , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Células Germinativas/metabolismo , Lisosomas/metabolismo , Lisosomas/patología , Neoplasias Pancreáticas
5.
Soft Matter ; 19(28): 5311-5317, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37403551

RESUMEN

Poly(dimethylsiloxane) (PDMS) bottlebrush elastomers (BBEs) are attractive soft materials with well-controlled bulk mechanical properties. However, their surface and interfacial properties have not been studied in depth. We report a detailed study of the adhesion of PDMS BBEs to glass using a contact adhesion test to determine the critical energy release rates, Gc, as a function of interfacial separation velocity. For BBEs, Gc for initiating separation, G0, was found to be independent of the crosslink density. We hypothesize that the monomer chemistry of side chains plays a primary role in defining surface properties for this materials system. After crack initiation, BBEs showed a significantly lower Gc and less velocity dependence than linear chain networks. Scaling analysis attributes these properties to the faster dissipative relaxation mechanisms within the BBEs. These findings demonstrate that the adhesion properties of BBEs can be finely tuned through the monomer chemistry and side chain length for potential applications.

6.
Acta Derm Venereol ; 103: adv11593, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37955529

RESUMEN

Atopic dermatitis is a chronic inflammatory skin  disease. Skin is the largest organ and plays a pivotal role in protecting the body. Not only does the skin act as a physical barrier against the external environment, but it also has its own immune system. Atopic dermatitis is caused by prolonged excessive inflammatory responses that worsen under imbalanced cutaneous immune system skin conditions. Although the prevalence and burden of atopic dermatitis is increasing, the standard therapeutic agents remain unclear due to  the complicated pathophysiology of the condition. The objective of this study is to examine the use of Magnoliae flos, the dried flower bud of Magnolia biondii or  related plants. The effects and underlying mechanism of  action of aqueous extract of the buds of Magnoliae flos (MF) were evaluated. Immortalized human keratinocytes (HaCaT) stimulated with tumour necrosis factor-α and interferon-γ mixture and NC/Nga mice stimulated with 2,4-dinitrochlorobenzene were used as atopic dermatitis models, in vitro and in vivo, respectively. The effects of MF were determined by measuring the suppression of pro-inflammatory signalling pathways, such as extracellular signal-regulated kinase or signal transducers and activators of transcription 1/3 and restoring skin barrier molecules. In conclusion, MF is a potential therapeutic alternative for the treatment of atopic dermatitis through repressing inflammatory pathways.


Asunto(s)
Dermatitis Atópica , Humanos , Ratones , Animales , Quinasas MAP Reguladas por Señal Extracelular/farmacología , Inmunoglobulina E , Línea Celular , Piel/patología , Inflamación , Factor de Necrosis Tumoral alfa/metabolismo , Flores/metabolismo , Citocinas
7.
J Chem Phys ; 159(18)2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37955325

RESUMEN

Many modern anti-icing and anti-fouling coatings rely on soft, low surface energy elastomeric materials such as polydimethylsiloxane for their functionality. While the low surface energy is desirable for reducing adhesion, very little work considers the larger contribution to adhesive failure caused by the viscoelastic nature of elastomers. Here we examine several different siloxane elastomers using a JKR adhesion test, which was operated over a range of different speeds and temperatures. Additionally, we characterize the dynamic mechanical modulus over a large range of frequencies for each material. We note that surface energies of the materials are all similar, but variation in adhesion strength is clear in the data. The variation at low speeds is related to elastomer architecture but the speed dependence itself is independent of architecture. Qualitative correlations are noted between the JKR adhesion measurements and the dynamic moduli. Finally, an attempt is made to directly compare moduli and adhesion through the recent Persson-Brener model. Approximations of the model are shown to be inaccurate. The full model is found to be accurate at low speeds, although it fails to precisely capture higher speed behaviour.

8.
Immun Ageing ; 20(1): 67, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38001481

RESUMEN

TLR4, a transmembrane receptor, plays a central role in the innate immune response. TLR4 not only engages with exogenous ligands at the cellular membrane's surface but also interacts with intracellular ligands, initiating intricate intracellular signaling cascades. Through MyD88, an adaptor protein, TLR4 activates transcription factors NF-κB and AP-1, thereby facilitating the upregulation of pro-inflammatory cytokines. Another adapter protein linked to TLR4, known as TRIF, autonomously propagates signaling pathways, resulting in heightened interferon expression. Recently, TLR4 has garnered attention as a significant factor in the regulation of symptoms in aging-related disorders. The persistent inflammatory response triggered by TLR4 contributes to the onset and exacerbation of these disorders. In addition, alterations in TLR4 expression levels play a pivotal role in modifying the manifestations of age-related diseases. In this review, we aim to consolidate the impact of TLR4 on cellular senescence and aging-related ailments, highlighting the potential of TLR4 as a novel therapeutic target that extends beyond immune responses.

9.
Proc Natl Acad Sci U S A ; 117(27): 15955-15966, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32554499

RESUMEN

Axon regeneration is regulated by a neuron-intrinsic transcriptional program that is suppressed during development but that can be reactivated following peripheral nerve injury. Here we identify Prom1, which encodes the stem cell marker prominin-1, as a regulator of the axon regeneration program. Prom1 expression is developmentally down-regulated, and the genetic deletion of Prom1 in mice inhibits axon regeneration in dorsal root ganglion (DRG) cultures and in the sciatic nerve, revealing the neuronal role of Prom1 in injury-induced regeneration. Elevating prominin-1 levels in cultured DRG neurons or in mice via adeno-associated virus-mediated gene delivery enhances axon regeneration in vitro and in vivo, allowing outgrowth on an inhibitory substrate. Prom1 overexpression induces the consistent down-regulation of cholesterol metabolism-associated genes and a reduction in cellular cholesterol levels in a Smad pathway-dependent manner, which promotes axonal regrowth. We find that prominin-1 interacts with the type I TGF-ß receptor ALK4, and that they synergistically induce phosphorylation of Smad2. These results suggest that Prom1 and cholesterol metabolism pathways are possible therapeutic targets for the promotion of neural recovery after injury.


Asunto(s)
Antígeno AC133/metabolismo , Axones/metabolismo , Colesterol/metabolismo , Regeneración Nerviosa/fisiología , Transducción de Señal , Células Madre/metabolismo , Antígeno AC133/genética , Receptores de Activinas Tipo I , Animales , Axones/patología , Colesterol/genética , Regulación hacia Abajo , Ganglios Espinales/metabolismo , Eliminación de Gen , Regulación de la Expresión Génica , Ratones , Ratones Noqueados , Neuronas/metabolismo , Traumatismos de los Nervios Periféricos/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Nervio Ciático
10.
Int J Mol Sci ; 24(19)2023 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-37834419

RESUMEN

Osteoarthritis (OA) affects >500 million people globally, and this number is expected to increase. OA management primarily focuses on symptom alleviation, using non-steroidal anti-inflammatory drugs, including Celecoxib. However, such medication has serious side effects, emphasizing the need for disease-specific treatment. The meniscectomy and cranial cruciate ligament transection (CCLx)-treated beagle dog was used to investigate the efficacy of a modified-release formulation of SKI306X (SKCPT) from Clematis mandshurica, Prunella vulgaris, and Trichosanthes kirilowii in managing arthritis. SKCPT's anti-inflammatory and analgesic properties have been assessed via stifle circumference, gait, incapacitance, histopathology, and ELISA tests. The different SKCPT concentrations and formulations also affected the outcome. SKCPT improved the gait, histopathological, and ELISA OA assessment parameters compared to the control group. Pro-inflammatory cytokines and matrix metalloproteinases were significantly lower in the SKCPT-treated groups than in the control group. This study found that SKCPT reduces arthritic lesions and improves abnormal gait. The 300 mg modified-release formulation was more efficacious than others, suggesting a promising approach for managing OA symptoms and addressing disease pathogenesis. A high active ingredient level and a release pattern make this formulation effective for twice-daily arthritis treatment.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Osteoartritis , Perros , Humanos , Animales , Ligamento Cruzado Anterior/cirugía , Ligamento Cruzado Anterior/patología , Meniscectomía , Osteoartritis/tratamiento farmacológico , Osteoartritis/etiología , Osteoartritis/patología , Antiinflamatorios no Esteroideos/uso terapéutico , Antiinflamatorios/uso terapéutico , Lesiones del Ligamento Cruzado Anterior/tratamiento farmacológico , Lesiones del Ligamento Cruzado Anterior/cirugía
11.
Small ; 18(27): e2201993, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35670200

RESUMEN

Polymersomes are vesicular structures self-assembled from amphiphilic block copolymers and are considered an alternative to liposomes for applications in drug delivery, immunotherapy, biosensing, and as nanoreactors and artificial organelles. However, the limited availability of systematic stability, protein fouling (protein corona formation), and blood circulation studies hampers their clinical translation. Poly(2-oxazoline)s (POx) are valuable antifouling hydrophilic polymers that can replace the current gold-standard, poly(ethylene glycol) (PEG), yet investigations of POx functionality on nanoparticles are relatively sparse. Herein, a systematic study is reported of the structural, dynamic and antifouling properties of polymersomes made of poly(2-methyl-2-oxazoline)-block-poly(dimethylsiloxane)-block-poly(2-methyl-2-oxazoline) (PMOXA-b-PDMS-b-PMOXA). The study relates in vitro antifouling performance of the polymersomes to atomistic molecular dynamics simulations of polymersome membrane hydration behavior. These observations support the experimentally demonstrated benefit of maximizing the length of PMOXA (degree of polymerization (DP) > 6) while keeping PDMS at a minimal length that still provides sufficient membrane stability (DP > 19). In vitro macrophage association and in vivo blood circulation evaluation of polymersomes in zebrafish embryos corroborate these findings. They further suggest that single copolymer presentation on polymersomes is outperformed by blends of varied copolymer lengths. This study helps to rationalize design rules for stable and low-fouling polymersomes for future medical applications.


Asunto(s)
Sistemas de Liberación de Medicamentos , Pez Cebra , Animales , Interacciones Hidrofóbicas e Hidrofílicas , Macrófagos , Oxazoles
12.
New Phytol ; 230(4): 1503-1516, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33570747

RESUMEN

The tight regulation of local auxin homeostasis and signalling maxima in xylem precursor cells specifies the organising activity of the vascular cambium and consequently promotes xylem differentiation and wood formation. However, the molecular mechanisms underlying the local auxin signalling maxima in the vascular cambium are largely unknown. Here, we reveal that brassinosteroid (BR)-activated WALLS ARE THIN1 (WAT1) facilitates wood formation by enhancing local auxin signalling in the vascular cambium in Solanum lycopersicum. Growth defects and low auxin signalling readouts in the BR-deficient tomato cultivar, Micro-Tom, were associated with a novel recessive allele, Slwat1-copi, created by the insertion of a retrotransposon in the last exon of the SlWAT1 locus. Molecular and genetic studies by generating the gain-of-function and loss-of-function tomato mutants revealed that SlWAT1 is a critical regulator for fine tuning local auxin homeostasis and signalling outputs in vascular cambium to facilitate secondary growth. Finally, we discovered that BR-regulated SlBZR1/2 directly activated downstream auxin responses by SlWAT1 upregulation in xylem precursor cells to facilitate xylem differentiation and subsequent wood formation. Our data suggest that the BR-SlBZR1/2-WAT1 signalling network contributes to the high level of auxin signalling in the vascular cambium for secondary growth.


Asunto(s)
Brasinoesteroides , Cámbium , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Madera/metabolismo , Xilema/metabolismo
13.
FASEB J ; 34(7): 9141-9155, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32421247

RESUMEN

Human-induced pluripotent stem cells (hiPSCs) are invaluable sources for drug screening and toxicity tests because of their differentiation potential and proliferative capacity. Recently, the CRISPR-Cas9-mediated homologous recombination system has enabled reporter knock-ins at desired loci in hiPSCs, and here, we generated a hiPSC reporter line expressing mCherry-tagged cytochrome P450 1A1 (CYP1A1), which can be utilized to screen for the modulators of aryl hydrocarbon receptor (AHR) in live cells. CYP1A1-mCherry hiPSCs exhibited typical characteristics of pluripotent stem cells such as marker expression, differentiation potential, and normal karyotype. After differentiation into hepatocyte-like cells (HLCs), CYP1A1-mCherry fusion protein was expressed and localized at the endoplasmic reticulum, and induced by AHR agonists. We obtained 23 hits modulating CYP1A1 expression from high-content screening with 241 hepatotoxicity chemicals and nuclear receptor ligands, and identified three upregulating chemicals and two downregulating compounds. Responses of hiPSC-HLCs against an AHR agonist were more similar to human primary hepatocytes than of HepG2 hepatocellular carcinoma cells. This platform has the advantages of live-cell screening without sacrificing cells (unlike previously available CYP1A1 reporter cell lines), as well as an indefinite supply of cells, and can be utilized in a wide range of screening related to AHR- and CYP1A1-associated diseases in desired cell types.


Asunto(s)
Citocromo P-450 CYP1A1/química , Fluorescencia , Hepatocitos/citología , Células Madre Pluripotentes Inducidas/citología , Preparaciones Farmacéuticas/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Diferenciación Celular , Citocromo P-450 CYP1A1/metabolismo , Células Hep G2 , Hepatocitos/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/enzimología , Transducción de Señal
14.
Int J Mol Sci ; 22(21)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34769428

RESUMEN

Oleanolic acid (OA) is a pentacyclic triterpenoid, abundantly found in plants of the Oleaceae family, and is well known for its beneficial pharmacological activities. Previously, we reported the inhibitory effect of OA on mast cell-mediated allergic inflammation. In this study, we investigated the effects of OA on atopic dermatitis (AD)-like skin lesions and its underlying mechanism of action. We evaluated the inhibitory effect of OA on AD-like responses and the possible mechanisms using a 1-chloro-2,4-dinitrochlorobenzene (DNCB)-induced AD animal model and tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated HaCaT keratinocytes. We found that OA has anti-atopic effects, including histological alterations, on DNCB-induced AD-like lesions in mice. Moreover, it suppressed the expression of Th2 type cytokines and chemokines in the AD mouse model and TNF-α/IFN-γ-induced HaCaT keratinocytes by blocking the activation of serine-threonine kinase Akt, nuclear factor-κB, and the signal transducer and activator of transcription 1. The results demonstrate that OA inhibits AD-like symptoms and regulates the inflammatory mediators; therefore, it may be used as an effective and attractive therapeutic agent for allergic disorders, such as AD. Moreover, the findings of this study provide novel insights into the potential pharmacological targets of OA for treating AD.


Asunto(s)
Citocinas/metabolismo , Dermatitis Atópica/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Queratinocitos/efectos de los fármacos , FN-kappa B/metabolismo , Ácido Oleanólico/farmacología , Animales , Línea Celular , Dermatitis Atópica/inducido químicamente , Dermatitis Atópica/metabolismo , Dermatitis Atópica/patología , Dinitroclorobenceno/toxicidad , Modelos Animales de Enfermedad , Humanos , Técnicas In Vitro , Inflamación/metabolismo , Inflamación/patología , Irritantes/toxicidad , Queratinocitos/metabolismo , Ratones , Ratones Endogámicos ICR , Transducción de Señal
15.
Molecules ; 26(20)2021 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-34684681

RESUMEN

Bisphenol A (BPA) is a typical environmental endocrine disruptor that exhibits estrogen-mimicking, hormone-like properties and can cause the collapse of bone homeostasis by an imbalance between osteoblasts and osteoclasts. Various BPA substitutes, structurally similar to BPA, have been used to manufacture 'BPA-free' products; however, the regulatory role of BPA alternatives in osteoclast differentiation still remains unelucidated. This study aimed to investigate the effects of these chemicals on osteoclast differentiation using the mouse osteoclast precursor cell line RAW 264.7. Results confirmed that both BPA and its alternatives, bisphenol F and tetramethyl bisphenol F (TMBPF), were nontoxic to RAW 264.7 cells. In particular, tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cell staining and activity calculation assays revealed that TMBPF enhanced osteoclast differentiation upon stimulation of the receptor activator of nuclear factor-kappa B ligand (RANKL). Additionally, TMBPF activated the mRNA expression of osteoclast-related target genes, such as the nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CtsK). Western blotting analysis indicated activation of the mitogen-activated protein kinase signaling pathway, including phosphorylation of c-Jun N-terminal kinase and p38. Together, the results suggest that TMBPF enhances osteoclast differentiation, and it is critical for bone homeostasis and skeletal health.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Estrógenos no Esteroides/farmacología , Osteoblastos/efectos de los fármacos , Fenoles/farmacología , Animales , Resorción Ósea , Diferenciación Celular/efectos de los fármacos , Estrógenos/análogos & derivados , Estrógenos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Proteínas Quinasas Activadas por Mitógenos/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Células RAW 264.7 , Transducción de Señal/efectos de los fármacos
16.
Int J Biometeorol ; 64(10): 1755-1765, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32588145

RESUMEN

In this study, the spatio-temporal characteristics of the minimum rest time for the safety of South Korean outdoor workers during hot summer months (June to August) are examined based on the hourly wet-bulb globe temperature (WBGT) across 27 weather stations in South Korea. The WBGT thresholds in the work-rest recommendation of the Korea Occupational Safety and Health Agency (KOSHA 2017) for the quantification of the minimum rest time are evaluated through a comparison of the given thresholds with the occurrences of occupational heat-related illness patients due to outdoor work during hot summer months in South Korea. The long-term (2009-2018) average of the hourly WBGT values during summer months shows that outdoor workers with a moderate workload are exposed to heat stress during approximately 30% of the entire daytime working hours (06:00-18:00). According to the WBGT thresholds modified from the KOSHA (2017) guidelines, the daily minimum rest time for a moderate workload noticeably increases up to 18% (11 min/h) in mid-summer (late July and early August). During mid-summer, the minimum rest time for a continuous moderate outdoor workload even increases up to 31% (18 min/h) between 12:00 and 13:00 and is regionally higher in the southwestern than in the southeastern regions of the Korean Peninsula. These results suggest that in summertime high-heat environments, a mandatory rest time must be provided according to appropriate heat management programs for the safety of workers.


Asunto(s)
Trastornos de Estrés por Calor , Exposición Profesional , Respuesta al Choque Térmico , Calor , Humanos , República de Corea
17.
Planta ; 250(4): 1371-1377, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31280329

RESUMEN

MAIN CONCLUSION: The brassinosteroid-related BES1 and BZR1 transcription factors dynamically modulate downstream gene networks via the TPL-HDA19 co-repressor complex in BR-signaling pathways in Arabidopsis thaliana. Brassinosteroids (BRs) are plant steroid hormones that are essential for diverse growth and developmental processes across the whole life cycle of plants. In Arabidopsis thaliana, the BR-related transcription factors BRI1-EMS-SUPPRESSOR 1 (BES1) and BRASSINAZOLE-RESISTANT 1 (BZR1) regulate a range of global gene expression in response to BR and several external signaling cues; however, the molecular mechanisms by which they mediate the reprogramming of downstream transcription remain unclear. We here report that formation of a protein complex between BES1 and BZR1 and Histone Deacetylase 19 (HDA19) via the conserved ERF-associated amphiphilic repression (EAR) motif proved essential for regulation of BR-signaling-related gene expression. Defects in BR-related functions of BES1 and BZR1 proteins containing a mutated EAR motif were completely rescued by artificial fusion with EAR-repression domain (SRDX), TOPLESS (TPL), or HDA19 proteins. RNA-sequencing analysis of Arabidopsis plants over-expressing bes1-DmEAR or bes1-DmEAR-HDA19 revealed an essential role for HDA19 activity in regulation of BES1/BZR1-mediated BR signaling. In addition to BR-related gene expression, the BES1-HDA19 transcription factor complex was important for abiotic stress-related drought stress tolerance and organ boundary formation. These results suggested that integrating activation of BR-signaling pathways with the formation of the protein complex containing BES1/BZR1 and TPL-HDA19 via the EAR motif was important in fine-tuning BR-related gene networks in plants.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Brasinoesteroides/metabolismo , Proteínas de Unión al ADN/metabolismo , Histona Desacetilasas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Secuencias de Aminoácidos , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Unión al ADN/genética , Redes Reguladoras de Genes , Histona Desacetilasas/genética , Complejos Multiproteicos , Transducción de Señal , Estrés Fisiológico
18.
Biomacromolecules ; 20(8): 2889-2903, 2019 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-31251565

RESUMEN

The recent progress in various biomaterials with unique physiological and pharmacological properties has expedited the development of translational medicines for the diagnosis, prognosis, and therapy of intractable diseases. Hyaluronic acid (HA) is one of such biomaterials that has attracted great attention due to its unique characteristics for biomedical applications. In this Perspective, we provide an overview of HA-based medicines in a variety of forms such as chemical and biological conjugates, nanoparticles, nanoparticle hybrid systems, hydrogels, and nanogels. We highlight the current-state-of-the-art strategies to design and optimize innovative HA-based medicines for their clinical translations. Finally, we discuss the challenges for technical hurdles and the future directions to expand the feasibility of HA-based translational medicines.


Asunto(s)
Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Ácido Hialurónico/química , Hidrogeles/química , Nanopartículas/química , Investigación Biomédica Traslacional , Animales , Humanos
19.
Molecules ; 24(18)2019 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-31491945

RESUMEN

SB365, a saponin D extracted from the roots of Pulsatilla koreana, has been reported to show cytotoxicity in several cancer cell lines. We investigated the effects of SB365 on U87-MG and T98G glioblastoma multiforme (GBM) cells, and its efficacy in combination with temozolomide for treating GBM. SB365 exerted a cytotoxic effect on GBM cells not by inducing apoptosis, as in other cancer cell lines, but by triggering caspase-independent cell death. Inhibition of autophagic flux and neutralization of the lysosomal pH occurred rapidly after application of SB365, followed by deterioration of mitochondrial membrane potential. A cathepsin B inhibitor and N-acetyl cysteine, an antioxidant, partially recovered cell death induced by SB365. SB365 in combination with temozolomide exerted an additive cytotoxic effect in vitro and in vivo. In conclusion, SB365 inhibits autophagic flux and induces caspase-independent cell death in GBM cells in a manner involving cathepsin B and mainly reactive oxygen species, and its use in combination with temozolomide shows promise for the treatment of GBM.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Caspasas/metabolismo , Pulsatilla/química , Saponinas/farmacología , Animales , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Biomarcadores , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Glioblastoma/metabolismo , Humanos , Metaloproteinasas de la Matriz , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Especies Reactivas de Oxígeno/metabolismo , Saponinas/química , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Biotechnol Lett ; 40(5): 755-763, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29464570

RESUMEN

OBJECTIVES: The aim of the study is to generate a spherical three-dimensional (3D) aggregate of hepatocyte-like cells (HLCs) differentiated from human embryonic stem cells and to investigate the effect of the 3D environment on hepatic maturation and drug metabolism. RESULTS: Quantitative real-time PCR analysis indicated that gene expression of mature hepatocyte markers, drug-metabolizing enzymes, and hepatic transporters was significantly higher in HLCs cultured in the 3D system than in those cultured in a two-dimensional system (p < 0.001). Moreover, hepatocyte-specific functions, including albumin secretion and bile canaliculi formation, were increased in HLCs cultured in the 3D system. In particular, 3D spheroidal culture increased expression of CES1 and BCHE, which encode hepatic esterases (p < 0.001). The enhanced activities of these hepatic esterases were confirmed by the cholinesterase activity assay and the increased susceptibility of HLCs to oseltamivir, which is metabolized by CES1. CONCLUSIONS: 3D spheroidal culture enhances the maturation and drug metabolism of stem cell-derived HLCs, and this may help to optimize hepatic differentiation protocols for hepatotoxicity testing.


Asunto(s)
Butirilcolinesterasa/genética , Hidrolasas de Éster Carboxílico/genética , Técnicas de Cultivo de Célula/métodos , Hepatocitos/citología , Células Madre Embrionarias Humanas/citología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Perfilación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hepatocitos/metabolismo , Células Madre Embrionarias Humanas/metabolismo , Humanos , Oseltamivir/farmacología , Esferoides Celulares/citología , Esferoides Celulares/metabolismo , Regulación hacia Arriba/efectos de los fármacos
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