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Mesoporous silica nanoparticles (MSNs) represent a promising avenue for targeted brain tumor therapy. However, the blood-brain barrier (BBB) often presents a formidable obstacle to efficient drug delivery. This study introduces a ligand-free PEGylated MSN variant (RMSN25-PEG-TA) with a 25 nm size and a slight positive charge, which exhibits superior BBB penetration. Utilizing two-photon imaging, RMSN25-PEG-TA particles remained in circulation for over 24 h, indicating significant traversal beyond the cerebrovascular realm. Importantly, DOX@RMSN25-PEG-TA, our MSN loaded with doxorubicin (DOX), harnessed the enhanced permeability and retention (EPR) effect to achieve a 6-fold increase in brain accumulation compared to free DOX. In vivo evaluations confirmed the potent inhibition of orthotopic glioma growth by DOX@RMSN25-PEG-TA, extending survival rates in spontaneous brain tumor models by over 28% and offering an improved biosafety profile. Advanced LC-MS/MS investigations unveiled a distinctive protein corona surrounding RMSN25-PEG-TA, suggesting proteins such as apolipoprotein E and albumin could play pivotal roles in enabling its BBB penetration. Our results underscore the potential of ligand-free MSNs in treating brain tumors, which supports the development of future drug-nanoparticle design paradigms.
Assuntos
Barreira Hematoencefálica , Doxorrubicina , Portadores de Fármacos , Nanopartículas , Dióxido de Silício , Animais , Humanos , Camundongos , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/administração & dosagem , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/química , Portadores de Fármacos/química , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Ligantes , Nanopartículas/química , Tamanho da Partícula , Polietilenoglicóis/química , Porosidade , Dióxido de Silício/químicaRESUMO
While temozolomide (TMZ) has been a cornerstone in the treatment of newly diagnosed glioblastoma (GBM), a significant challenge has been the emergence of resistance to TMZ, which compromises its clinical benefits. Additionally, the nonspecificity of TMZ can lead to detrimental side effects. Although TMZ is capable of penetrating the blood-brain barrier (BBB), our research addresses the need for targeted therapy to circumvent resistance mechanisms and reduce off-target effects. This study introduces the use of PEGylated mesoporous silica nanoparticles (MSN) with octyl group modifications (C8-MSN) as a nanocarrier system for the delivery of docetaxel (DTX), providing a novel approach for treating TMZ-resistant GBM. Our findings reveal that C8-MSN is biocompatible in vitro, and DTX@C8-MSN shows no hemolytic activity at therapeutic concentrations, maintaining efficacy against GBM cells. Crucially, in vivo imaging demonstrates preferential accumulation of C8-MSN within the tumor region, suggesting enhanced permeability across the blood-brain tumor barrier (BBTB). When administered to orthotopic glioma mouse models, DTX@C8-MSN notably prolongs survival by over 50%, significantly reduces tumor volume, and decreases side effects compared to free DTX, indicating a targeted and effective approach to treatment. The apoptotic pathways activated by DTX@C8-MSN, evidenced by the increased levels of cleaved caspase-3 and PARP, point to a potent therapeutic mechanism. Collectively, the results advocate DTX@C8-MSN as a promising candidate for targeted therapy in TMZ-resistant GBM, optimizing drug delivery and bioavailability to overcome current therapeutic limitations.
Assuntos
Barreira Hematoencefálica , Docetaxel , Resistencia a Medicamentos Antineoplásicos , Glioblastoma , Nanopartículas , Dióxido de Silício , Temozolomida , Temozolomida/química , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Temozolomida/farmacocinética , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Docetaxel/química , Docetaxel/farmacologia , Docetaxel/farmacocinética , Docetaxel/uso terapêutico , Dióxido de Silício/química , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Animais , Nanopartículas/química , Humanos , Camundongos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Porosidade , Portadores de Fármacos/química , Camundongos Nus , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacosRESUMO
Conventional histopathology involves expensive and labor-intensive processes that often consume tissue samples, rendering them unavailable for other analyses. We present a novel end-to-end workflow for pathology powered by hyperspectral microscopy and deep learning. First, we developed a custom hyperspectral microscope to nondestructively image the autofluorescence of unstained tissue sections. We then trained a deep learning model to use autofluorescence to generate virtual histologic stains, which avoids the cost and variability of chemical staining procedures and conserves tissue samples. We showed that the virtual images reproduce the histologic features present in the real-stained images using a randomized nonalcoholic steatohepatitis (NASH) scoring comparison study, where both real and virtual stains are scored by pathologists (D.T., A.D.B., R.K.P.). The test showed moderate-to-good concordance between pathologists' scoring on corresponding real and virtual stains. Finally, we developed deep learning-based models for automated NASH Clinical Research Network score prediction. We showed that the end-to-end automated pathology platform is comparable with an independent panel of pathologists for NASH Clinical Research Network scoring when evaluated against the expert pathologist consensus scores. This study provides proof of concept for this virtual staining strategy, which could improve cost, efficiency, and reliability in pathology and enable novel approaches to spatial biology research.
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Aprendizado Profundo , Hepatopatia Gordurosa não Alcoólica , Humanos , Microscopia , Reprodutibilidade dos Testes , PatologistasRESUMO
The combination of photoacoustic (PA) imaging and ultrasound localization microscopy (ULM) with microbubbles has great potential in various fields such as oncology, neuroscience, nephrology, and immunology. Here we developed an interleaved PA/fast ULM imaging technique that enables super-resolution vascular and physiological imaging in less than 2 seconds per frame in vivo. By using sparsity-constrained (SC) optimization, we accelerated the frame rate of ULM up to 37 times with synthetic data and 28 times with in vivo data. This allows for the development of a 3D dual imaging sequence with a commonly used linear array imaging system, without the need for complicated motion correction. Using the dual imaging scheme, we demonstrated two in vivo scenarios challenging to image with either technique alone: the visualization of a dye-labeled mouse lymph node showing nearby microvasculature, and a mouse kidney microangiography with tissue oxygenation. This technique offers a powerful tool for mapping tissue physiological conditions and tracking the contrast agent biodistribution non-invasively.
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Meios de Contraste , Imageamento Tridimensional , Camundongos , Animais , Distribuição Tecidual , Ultrassonografia/métodos , Imageamento Tridimensional/métodos , Microscopia/métodos , MicrobolhasRESUMO
Afatinib is used to treat non-small cell lung cancer cells (NSCLC), and its mechanism involves irreversible inhibition of epidermal growth factor receptor (EGFR) tyrosine kinase. In this study, we examined if afatinib had cytotoxic action against NSCLC other than inhibition of tyrosine kinase. Afatinib (1-30 µM) caused apoptotic death in A549 NSCLC in a concentration-dependent manner. Afatinib triggered Ca2+ influx without causing Ca2+ release, and the Ca2+ influx was unaffected by sodium orthovanadate (SOV, an inhibitor of tyrosine phosphatase), suggesting that afatinib-triggered Ca2+ response was unrelated to its inhibition of tyrosine kinase. Addition of afatinib also promoted Mn2+ influx. Ca2+ influx triggered by afatinib was resistant to SKF96365 and ruthenium red (two general blockers of TRP channels) and, unexpectedly, Ni2+ (a non-specific Ca2+ channel blocker). Afatinib caused an increase in mitochondrial Ca2+ level, an initial mitochondrial hyperpolarization (4 h) and followed by mitochondrial potential collapse (24-48 h). Afatinib-induced cell death was slightly but significantly alleviated in low extracellular Ca2+ condition or under pharmacological block of mitochondrial permeability transition pore (MPTP) opening by cyclosporin A. Therefore, in addition to tyrosine kinase inhibition as a major anti-cancer mechanism of afatinib, stimulation of an atypical Ca2+ influx pathway, mitochondrial Ca2+ overload, and potential collapse in part contribute to afatinib-induced cell death.
Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Afatinib/farmacologia , Afatinib/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Receptores ErbB , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , MutaçãoRESUMO
The current clinical management model of HER2-positive breast cancers is commonly based on guidelines, which in turn are based on the design and outcome of clinical trials. While this model is useful to most practicing clinicians, the treatment outcome of individual patient is not certain at the start of treatment. As the understanding of the translational research of carcinogenesis and the related changes in cancer genetics and tumor microenvironment during treatment is critical in the selection of right choice of treatment to maximize the successful clinical outcome for the patient, this review article intends to discuss the latest developments in the genetic and molecular mechanisms of cancer progression and treatment resistance, and how they influence the planning of the treatment strategies of HER2-positive breast cancers.
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ABSTRACT: Propofol, a general anesthetic administered intravenously, may cause pain at the injection site. The pain is in part due to irritation of vascular endothelial cells. We here investigated the effects of propofol on Ca2+ transport and pain mediator release in human umbilical vein endothelial cells (EA.hy926). Propofol mobilized Ca2+ from cyclopiazonic acid (CPA)-dischargeable pool but did not cause Ca2+ release from the lysosomal Ca2+ stores. Propofol-elicited Ca2+ release was suppressed by 100 µM ryanodine, suggesting the participation of ryanodine receptor channels. Propofol did not affect ATP-triggered Ca2+ release but abolished the Ca2+ influx triggered by ATP; in addition, propofol also suppressed store-operated Ca2+ entry elicited by CPA. Ca2+ clearance during CPA-induced Ca2+ discharge was unaffected by a low Na+ (50 mM) extracellular solution, but strongly suppressed by 5 mM La3+ (an inhibitor of plasmalemmal Ca2+ pump), suggesting Ca2+ extrusion was predominantly through the plasmalemmal Ca2+ pump. Propofol mimicked the effect of La3+ in suppressing Ca2+ clearance. Propofol also stimulated release of pain mediators, namely, reactive oxygen species and bradykinin. Our data suggest propofol elicited Ca2+ release and repressed Ca2+ clearance, causing a sustained cytosolic [Ca2+]i elevation. The latter may cause reactive oxygen species and bradykinin release, resulting in pain.
Assuntos
Propofol , Canal de Liberação de Cálcio do Receptor de Rianodina , Trifosfato de Adenosina , Bradicinina/farmacologia , Cálcio/metabolismo , Células Endoteliais/metabolismo , Humanos , Dor , Propofol/farmacologia , Espécies Reativas de Oxigênio , Rianodina/farmacologiaRESUMO
The edible leaves of the mulberry (Morus alba L.) plant are used worldwide. They contain abundant polyphenolic compounds with strong anticancer properties. We previously revealed that apoptosis was mediated in p53-negative Hep3B cells, and mulberry leaf polyphenol extract (MLPE) induced autophagy in p53-transfected Hep3B cells. However, how this autophagy is induced by p53 in human hepatoma HepG2 (p53 wild type) cells remains unclear. In the current study, MLPE induced autophagy, as demonstrated by enhanced acidic vesicular organelle staining, by upregulating beclin-1, increasing LC3-II conversion, and phosphorylating AMPK. In HepG2 cells, these processes were associated with p53. Western blot also revealed phosphatidylinositol-3 kinase (PI3K), p-AKT, and fatty acid synthase (FASN) suppression in MLPE-treated cells. Moreover, treatment with the p53 inhibitor pifithrin-α (PFT-α) inhibited autophagy and increased apoptotic response in MLPE-treated HepG2 cells. PFT-α treatment also reversed MLPE-induced PI3K, p-AKT, and FASN suppression. Thus, co-treatment with MLPE and PFT-α significantly increased caspase-3, caspase-8, and cytochrome c release, indicating that p53 deficiency caused the apoptosis. In addition, rutin, a bioactive polyphenol in MLPE, may affect autophagy in HepG2 cells. This study demonstrates that MLPE is a potential anticancer agent targeting autophagy and apoptosis in cells with p53 status. Moreover, this work provides insight into the mechanism of p53 action in MLPE-induced cytotoxicity in hepatocellular carcinoma.
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Gamma-linolenic acid (GLA), a natural fatty acid obtained from oils of various vegetables and seeds, has been demonstrated as an anticancer agent. In this work, we investigated the anticancer effects of GLA on breast cancer BT-474 cells. GLA at 30 µM, a concentration reportedly within the range of circulating concentrations in clinical studies, caused apoptotic cell death. GLA caused an elevation in mitochondrial Ca2+ level and a decrease in mitochondrial membrane potential. GLA treatment depleted cyclopiazonic acid (CPA)-sensitive Ca2+ store and triggered substantial Ca2+ influx. Intracellular Ca2+ release triggered by GLA was suppressed by 3 µM xestospongin C (XeC, IP3 receptor-channel blocker) and 100 µM ryanodine (ryanodine receptor-channel blocker), suggesting that the Ca2+ release was via IP3 receptor-channel and ryanodine receptor-channel. Increased expressions of p-eIF2α and CHOP were observed in GLA-treated cells, suggesting GLA-treated cells had increased expressions of p-eIF2α and CHOP, which suggest endoplasmic reticulum (ER) stress. In addition, GLA elicited increased production of reactive oxygen species. Taken together, our results suggest a basal level of GLA induced apoptotic cell death by causing Ca2+ overload, mitochondrial dysfunction, Ca2+ store depletion, ER stress, and oxidative stress. This is the first report to show that GLA caused Ca2+ store depletion and ER stress. GLA-induced Ca2+ store depletion resulted from opening of IP3 receptor-channel and ryanodine receptor-channel.
Assuntos
Neoplasias da Mama , Ácido gama-Linolênico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Feminino , Humanos , Estresse Oxidativo , Ácido gama-Linolênico/metabolismoRESUMO
Reversing the immunosuppressive tumor microenvironment (TME) is a strategic initiative to sensitize cancer immunotherapy. Emerging evidence shows that cyclic diguanylate monophosphate (c-di-GMP or cdG) can induce the stimulator of interferon genes (STING) pathway activation of antigen-presenting cells (APCs) and upregulate expression of type I interferons (IFNs) to enhance tumor immunogenicity. In vitro anionic cdG revealed fast plasma clearance, poor membrane permeability, and inadequate cytosolic bioavailability. Therefore, we explored a comprehensive "in situ vaccination" strategy on the basis of nanomedicine to trigger robust antitumor immunity. Rhodamine B isothiocyanate (RITC) fluorescent mesoporous silica nanoparticles (MSN) synthesized and modified with poly(ethylene glycol) (PEG) and an ammonium-based cationic molecule (TA) were loaded with negatively charged cdG via electrostatic interactions to form cdG@RMSN-PEG-TA. Treatment of RAW 264.7 cells with cdG@RMSN-PEG-TA markedly stimulated the secretion of IL-6, IL-1ß, and IFN-ß along with phospho-STING (Ser365) protein expression. In vivo cdG@RMSN-PEG-TA enhanced infiltration of leukocytes, including CD11c+ dendritic cells, F4/80+ macrophages, CD4+ T cells, and CD8+ T cells within the tumor microenvironment (TME), resulting in dramatic tumor growth inhibition in 4T1 breast tumor-bearing Balb/c mice. Our findings suggest that a nanobased platform can overcome the obstacles bare cdG can face in the TME. Our approach of an in situ vaccination using a STING agonist provides an attractive immunotherapy-based strategy for treating breast cancer.
Assuntos
Neoplasias da Mama/terapia , GMP Cíclico/análogos & derivados , Ativação Linfocitária/efeitos dos fármacos , Proteínas de Membrana/agonistas , Nanopartículas/química , Dióxido de Silício/química , Animais , Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , GMP Cíclico/farmacologia , Feminino , Corantes Fluorescentes/química , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos BALB C , Porosidade , Células RAW 264.7 , Rodaminas/química , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/imunologiaRESUMO
Two-photon microscopy is a mainstay technique for imaging in scattering media and normally provides frame-acquisition rates of ~10-30 Hz. To track high-speed phenomena, we created a two-photon microscope with 400 illumination beams that collectively sample 95,000-211,000 µm2 areas at rates up to 1 kHz. Using this microscope, we visualized microcirculatory flow, fast venous constrictions and neuronal Ca2+ spiking with millisecond-scale timing resolution in the brains of awake mice.
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Encéfalo/irrigação sanguínea , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Animais , Cálcio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , VigíliaRESUMO
Mulberry (Morus alba L.) leaves are used in Chinese medicine to treat metabolic disorders. Mulberry leaf polyphenol extracts (MLPE) have recently been shown to exhibit anticancer properties. Endoplasmic reticulum (ER) stress represents a pivotal obstacle in solid tumors, resulting in the antiapoptosis of tumor cells and drug resistance. In this study, pretreatment with the ER stress inducer tunicamycin (TM) attenuated the percentage of apoptosis induced by doxorubicin (DOX). Cotreatment with tunicamycin and MLPE reversed apoptosis induced by DOX. Simultaneously, induction of ER stress with tunicamycin resulted in an increased expression of Cyclooxygenase 2 (COX-2) and Glucose-regulated protein (GRP78) concomitant with the activation of p38 MAPK/PI3K/Akt in HepG2 cells. Furthermore, the suppression of ER stress with celecoxib or p38 MAPK inhibitor successfully recovered DOX-induced apoptosis. Consistent with the inhibition of COX-2 or p38 MAPK, copretreatment with TM and MLPE drastically recovered cytotoxicity and caspase-3 activation in the presence of DOX. These results reveal that MLPE reduces ER stress-induced resistance to DOX in hepatocellular carcinoma (HCC) cells through downregulation of COX-2- or p38 MAPK-mediated PI3K/Akt pathway.
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Optical imaging through the intact mouse skull is challenging because of skull-induced aberrations and scattering. We found that three-photon excitation provided improved optical sectioning compared with that obtained with two-photon excitation, even when we used the same excitation wavelength and imaging system. Here we demonstrate three-photon imaging of vasculature through the adult mouse skull at >500-µm depth, as well as GCaMP6s calcium imaging over weeks in cortical layers 2/3 and 4 in awake mice, with 8.5 frames per second and a field of view spanning hundreds of micrometers.
Assuntos
Encéfalo/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Neuroimagem/métodos , Crânio/fisiologia , Animais , Encéfalo/anatomia & histologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Crânio/anatomia & histologiaRESUMO
Staphylococcus aureus (S. aureus) can lead to many life-threatening diseases. It has the ability to invade normal endovascular tissue. The molecular mechanisms and pathological changes of endothelial cells after S. aureus infection are of interest, but the basic understanding of how S. aureus destroys this barrier is not clear. Here, we showed that S. aureus enhanced COX-2 expression and prostaglandin E2 (PGE2) secretion in human aortic endothelial cells (HAECs). In addition, S. aureus induced PGE2/interleukin-6 (IL-6)/matrix metallopeptidase-9 (MMP-9)-dependent cell migration. S. aureus-induced COX-2, IL-6, and MMP-9 levels were inhibited by transfection with siRNA of Toll-like receptor 2 (TLR2), p38, p42, p44, p50, or p65. S. aureus also induced p38 MAPK, ATF2, ERK1/2, and NF-κB p65 activation. Interestingly, we proved that S. aureus decreased intracellular generation of reactive oxygen species (ROS), which suggests that the inhibition of ROS production promoted inflammatory responses. Finally, we showed that S. aureus enhanced a variety of biomarkers of inflammation in cardiovascular diseases. However, the free radical scavenger (MCI-186) or antioxidant (N-acetyl-L-cysteine, NAC) markedly enhanced S. aureus-induced COX-2 mRNA levels in the aorta tissues. Taken together, these findings established that S. aureus promoted aorta inflammation via activation of p38 MAPK, ERK1/2, and NF-κB and inhibition of ROS generation.
Assuntos
Aorta/patologia , Inflamação/patologia , Infecções Estafilocócicas/fisiopatologia , Staphylococcus aureus/isolamento & purificação , Animais , Antioxidantes/farmacologia , Aorta/microbiologia , Doenças Cardiovasculares/microbiologia , Doenças Cardiovasculares/fisiopatologia , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Sequestradores de Radicais Livres/farmacologia , Humanos , Inflamação/microbiologia , Interleucina-6/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Staphylococcus aureus (S. aureus) can often lead to many life-threatening diseases. It has the ability to invade normal endovascular tissue. Acute inflammation and its resolution are important to ensure bacterial clearance and limit tissue injury. Carbon monoxide (CO) has been shown to exert anti-inflammatory effects in various tissues and organ systems. In our study, we investigated the effects and the mechanisms of carbon monoxide releasing molecule-2 (CORM-2) on S. aureus-induced inflammatory responses in human aortic endothelial cells (HAECs). We proved that S. aureus induced cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2)/interleukin-6 (IL-6)/matrix metallopeptidase-9 (MMP-9) expression and cell migration, which were decreased by CORM-2. Moreover, CORM-2 had no effects on TLR2 mRNA levels in response to S. aureus. Interestingly, we proved that S. aureus decreased intracellular ROS generation, suggesting that the inhibition of ROS further promoted inflammatory responses. However, CORM-2 significantly inhibited S. aureus-induced inflammation by increasing intracellular ROS generation. S. aureus-induced NF-κB activation was also inhibited by CORM-2. Finally, we proved that S. aureus induced levels of the biomarkers of inflammation in cardiovascular diseases, which were inhibited by CORM-2. Taken together, these results suggest that CORM-2 inhibits S. aureus-induced COX-2/PGE2/IL-6/MMP-9 expression and aorta inflammatory responses by increasing the ROS generation and reducing the inflammatory molecules levels.
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Aorta/imunologia , Monóxido de Carbono/farmacologia , Movimento Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/imunologia , Células Endoteliais/imunologia , Interleucina-6/imunologia , Metaloproteinase 9 da Matriz/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Aorta/patologia , Movimento Celular/imunologia , Células Cultivadas , Células Endoteliais/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Compostos Organometálicos/farmacologia , Infecções Estafilocócicas/patologiaRESUMO
Pseudomonas aeruginosa (P. aeruginosa) infection in the lung is common in patients with cystic fibrosis (CF). Intercellular adhesion molecule-1 (ICAM-1) is known to play a key role in lung inflammation. Acute inflammation and its timely resolution are important to ensure bacterial clearance and limit tissue damage. Carbon monoxide (CO) has been shown to exert anti-inflammatory effects in various tissues and organ systems. Here, we explored the protective effects and mechanisms of carbon monoxide releasing molecule-2 (CORM-2) on P. aeruginosa-induced inflammatory responses in human pulmonary alveolar epithelial cells (HPAEpiCs). We showed that P. aeruginosa induced prostaglandin E2 (PGE2)/interleukin-6 (IL-6)/ICAM-1 expression and monocyte adherence to HPAEpiCs. Moreover, P. aeruginosa-induced inflammatory responses were inhibited by transfection with siRNA of Toll-like receptor 4 (TLR4), PKCα, p47phox, JNK2, p42, p50, or p65. P. aeruginosa also induced PKCα, JNK, ERK1/2, and NF-κB activation. We further demonstrated that P. aeruginosa increased intracellular ROS generation via NADPH oxidase activation. On the other hand, P. aeruginosa-induced inflammation was inhibited by pretreatment with CORM-2. Preincubation with CORM-2 had no effects on TLR4 mRNA levels in response to P. aeruginosa. However, CORM-2 inhibits P. aeruginosa-induced inflammation by decreasing intracellular ROS generation. P. aeruginosa-induced PKCα, JNK, ERK1/2, and NF-κB activation was inhibited by CORM-2. Finally, we showed that P. aeruginosa induced levels of the biomarkers of inflammation in respiratory diseases, which were inhibited by pretreatment with CORM-2. Taken together, these data suggest that CORM-2 inhibits P. aeruginosa-induced PGE2/IL-6/ICAM-1 expression and lung inflammatory responses by reducing the ROS generation and the inflammatory pathways.
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Células Epiteliais Alveolares/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Molécula 1 de Adesão Intercelular/imunologia , Compostos Organometálicos/farmacologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Espécies Reativas de Oxigênio/imunologia , Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/microbiologia , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Inflamação/complicações , Inflamação/tratamento farmacológico , Inflamação/imunologia , Interleucina-6/imunologia , Masculino , Camundongos Endogâmicos ICR , Infecções por Pseudomonas/complicações , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacosRESUMO
Acarbose, an α-glucosidase inhibitor, is reported to reduce the incidence of silent myocardial infarction and slow the progression of intima-media thickening in patients with glucose intolerance. Here we investigate other impacts of acarbose on atherosclerosis development and the underlying mechanisms of atherosclerosis initiation and progression in vivo and in vitro. Rabbits fed a high cholesterol diet (HCD) were treated with acarbose (2.5-5.0 mg kg-1). Immunohistochemistry was used to assess the expression of inducible nitric oxide synthase (iNOS), Ras, proliferating cell nuclear antigen (PCNA), IL-6, ß-galactosidase, and p-AMPK in atherosclerotic lesions. Treatment with acarbose in HCD-fed rabbits was found to significantly reduce the severity of aortic atheroma and neointimal expression of α-actin, PCNA, IL-6, TNF-α, Ras, and ß-galactosidase; to significantly increase expression of iNOS and p-AMPK, but not to affect serum levels of glucose, total cholesterol, and LDL. Western blot analysis showed acarbose dose-dependently decreased ß-galactosidase and Ras expression and increased p-AMPK expression in TNF-α-treated A7r5 cells. In addition, acarbose restored p-AMPK and iNOS levels in AMPK inhibitor- and iNOS inhibitor-treated A7r5 cells, respectively. In conclusion, acarbose can pleiotropically inhibit rabbit atherosclerosis by reducing inflammation, senescence, and VSMCs proliferation/migration via upregulating AMPK signals.
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Acarbose/efeitos adversos , Aterosclerose/etiologia , Aterosclerose/metabolismo , Inibidores de Glicosídeo Hidrolases/efeitos adversos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Animais , Aterosclerose/patologia , Biomarcadores , Peso Corporal/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Imuno-Histoquímica , Lipídeos/sangue , Masculino , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , CoelhosRESUMO
RNA is a drug target involved in diverse cellular functions and viral processes. Molecules that inhibit the HIV TAR RNA-Tat protein interaction may attenuate Tat/TAR-dependent protein expression and potentially serve as anti-HIV therapeutics. By incorporating positively charged residues with mixed side chain lengths, we designed peptides that bind TAR RNA with enhanced intracellular activity. Tat-derived peptides that were individually substituted with positively charged residues with varying side chain lengths were evaluated for TAR RNA binding. Positively charged residues with different side chain lengths were incorporated at each Arg and Lys position in the Tat-derived peptide to enhance TAR RNA binding. The resulting peptides showed enhanced TAR RNA binding affinity, cellular uptake, nuclear localization, proteolytic resistance, and inhibition of intracellular Tat/TAR-dependent protein expression compared to the parent Tat-derived peptide with no cytotoxicity. Apparently, the enhanced inhibition of protein expression by these peptides was not determined by RNA binding affinity, but by proteolytic resistance. Despite the high TAR binding affinity, a higher binding specificity would be necessary for practical purposes. Importantly, altering the positively charged residue side chain length should be a viable strategy to generate potentially useful RNA-targeting bioactive molecules.
Assuntos
Fármacos Anti-HIV/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Produtos do Gene tat/farmacologia , Repetição Terminal Longa de HIV , HIV/genética , Peptídeos/farmacologia , RNA Viral/genética , Sequência de Aminoácidos , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacocinética , Linhagem Celular , Produtos do Gene tat/química , Produtos do Gene tat/farmacocinética , HIV/efeitos dos fármacos , HIV/metabolismo , Infecções por HIV/tratamento farmacológico , Repetição Terminal Longa de HIV/efeitos dos fármacos , Humanos , Peptídeos/química , Peptídeos/farmacocinética , RNA Viral/metabolismoRESUMO
Excess fat accumulation in the liver increases the risk of developing progressive liver injuries ranging from a fatty liver to hepatocarcinoma. In a previous study, we demonstrated that the polyphenol components of Sechium edule shoots attenuated hepatic lipid accumulation in vitro. Therefore, we investigated the effects and mechanisms of the extract of S. edule shoots (SWE) to modulate fat accumulation in a high-fat-diet (HFD)-induced animal model. In this study, we found that the SWE can reduce the body weight, adipose tissue fat, and regulate hepatic lipid contents (e.g., triglyceride and cholesterol). Additionally, treatment of caffeic acid (CA) and hesperetin (HPT), the main ingredients of SWE, also inhibited oleic acid (OA)-induced lipid accumulation in HepG2 cells. SWE enhanced the activation of AMP-activating protein kinase (AMPK) and decreased numerous lipogenic-related enzymes, such as sterol regulator element-binding proteins (SREBPs), e.g., SREBP-1 and SREBP-2, and HMG-CoA reductase (HMGCoR) proteins, which are critical regulators of hepatic lipid metabolism. Taken together, the results demonstrated that SWE can prevent a fatty liver and attenuate adipose tissue fat by inhibiting lipogenic enzymes and stimulating lipolysis via upregulating AMPK. It was also demonstrated that the main activation components of SWE are both CA and HPT.
Assuntos
Adipogenia/efeitos dos fármacos , Cucurbitaceae/química , Fígado Gorduroso/tratamento farmacológico , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Obesidade/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/fisiopatologia , Humanos , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Fígado/metabolismo , Masculino , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Ácido Oleico/metabolismo , Extratos Vegetais/química , Brotos de Planta/química , Ratos , Ratos Wistar , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismoRESUMO
Adolescent mental health is crucial for social competence and accomplishment in later life. The World Health Organization (WHO) estimates that approximately 20% of adolescents suffer from psychological symptoms. However, improving family risk and school environments can largely promote adolescent mental health. A longitudinal survey was conducted to investigate adolescent psychological well-being (PWB) status and associated factors in adolescents 15-20 years of age. Family and school context variables were interviewed and recorded. A total of 2896 participants were included from high, middle, and less urbanized resident areas in Northern Taiwan with completed interview data. Using multivariate regression analysis, factors associated with adolescent PWB at various stages included quarrelsome parents, quarrels with parents, severed friendships, and cigarette and alcohol use. In all three adolescent stages, females yielded higher psychological symptom scores than did males, and diverse weights of risk factors on PWB were observed between genders. Family arguments and cigarette and alcohol use were found to have more pronounced effects on outcomes among females than males. Whereas males are more sensitive to severed friendships than females, cigarette and alcohol use showed more harmful effects on mental health in earlier adolescence than in later life. Moreover, family arguments and severed friendships in earlier adolescence were found to have lasting effects on PWB in later adolescence. In this study, gender differences were observed in the temporal relationship on adolescent mental health. Variables of family arguments and severed friendships exhibited short-term and long-term effects on adolescent mental health across the early to late developmental stages. The family argument environment and regulating cigarette and alcohol use are worthy of focus to promote adolescent mental health.