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BACKGROUND: Breast cancer is the most common cancer worldwide, with the fifth highest mortality rate among all cancers and high risk of metastasis. However, potential biomarkers and molecular mechanisms underlying the stratification of breast cancer in terms of clinical outcomes remain to be investigated. Therefore, we aimed to find a novel prognostic biomarker and therapeutic target for breast cancer patients. METHODS: Unsupervised hierarchical clustering was used to perform comprehensive transcriptomic study of total 185 glycogenes in public datasets of breast cancer with clinicopathological and survival information. A glycogene-based signature for subtype classification was discovered using Limma packages, and relevance to four known molecular features was identified by GSVA. Experimental verification was performed and biological functions of B3GNT7 were characterized by quantitative RT-PCR, western blot, transwell assays, and lectin immunofluorescence staining in breast cancer cells. RESULTS: A 23-glycogene signature was identified for the classification of breast cancer. Among the 23 glycogenes, B3GNTs showed significantly positive associations with ER-/Her2- subtype in breast cancer patients (n = 2655). Overexpressed B3GNT7 were correlated with poor prognosis in breast cancer patients based on public datasets. B3GNT7 depletion inhibited cell proliferation, migration, and invasion, and decreased global fucosylation in MDA-MB-231 and HCC1937 breast cancer cells. CONCLUSIONS: Herein, we discovered a unique 23-gene signature for breast cancer patient glycogene-type classification. Among these genes, B3GNT7 was shown to be a potential biomarker for unfavorable outcomes and therapeutic target of breast cancer.
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Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Perfilação da Expressão Gênica , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Prognóstico , Transcriptoma , Biomarcadores Tumorais/genéticaRESUMO
Cancer stem cells (CSCs) have been demonstrated to be involved in tumor initiation and relapse, and the presence of CSCs in the tumor tissue often leads to therapeutic failure. BBI608 has been identified to eliminate CSCs by inhibiting signal transducer and activator of transcription 3 (STAT3). In this study, we confirm that BBI608 can efficiently suppress the proliferation and migration of non-small cell lung cancer (NSCLC) cells, and specifically kill the stemness-high population in chemoresistant NSCLC cells. To improve its bioavailability and tumor accumulation, BBI608 is successfully encapsulated into redox-responsive PEGylated branched N-(2-hydroxypropyl) methacrylamide (HPMA)-deoxy cholic acid (DA) polymeric nanoparticles (BBI608-SS-NPs). The BBI608-SS-NPs can release the drug in response to high concentrations of intracellular glutathione, and exhibit cytotoxicity against lung cancer cells and CSCs comparable to the free drug BBI608. Furthermore, the BBI608-SS-NPs preferentially accumulate in tumor sites, resulting in a superior anti-tumor efficacy in both cisplatin-resistant cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) models of NSCLC. Mechanistic studies demonstrate that BBI608-SS-NPs not only directly inhibit the downstream genes of the STAT3 pathway, but also indirectly inhibit the Wnt pathway. Overall, this stimuli-responsive polymeric nanoformulation of BBI608 shows great potential in the treatment of chemoresistant NSCLC by targeting CSCs.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Fator de Transcrição STAT3/metabolismo , Oxirredução , Proliferação de Células , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/metabolismoRESUMO
The state of growth of invasive species has a significant impact on the microbial regulation of the soil carbon (C) cycle. This study focused on the growth of Spartina alterniflora treated with imazapyr in the Tiaozini wetland of Jiangsu Province, China. The changes in soil bacterial structure, bacterial C metabolic activity, soil C, and regulation mechanism of soil C metabolic activity by biotic and abiotic factors were investigated. The results showed that soil bacterial diversity eventually decreased significantly (p < 0.05) along with significant changes in microbial structure (p < 0.05). Significant changes in soil physicochemical properties due to S. alterniflora growth inhibition were the key factors affecting the changes in the soil bacterial taxa composition (p < 0.05). Abiotic factors showed a greater effect on metabolic activities related to C fixation and biosynthesis of bacterial taxa than biotic factors (self-regulation). Additionally, bacterial taxa regulated soil C emission and degradation to a greater extent than abiotic factors. This study provides important information for understanding the regulators of C cycling in coastal wetland soil during the control of S. alterniflora invasion by imazapyr; moreover, it provides a scientific basis for the government to establish a prevention and control policy for S. alterniflora invasion. Understanding the complex interplay between abiotic and biotic factors is essential for developing effective strategies to manage soil C and mitigate the impacts of climate change.
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Latexin (LXN) plays an important role in tumorigenesis and inflammatory response and as a tumor suppressor in many tumors. However, whether LXN regulates tumorigenesis through immune regulation remains uncertain. Here, we demonstrate that LXN deficiency increases hematopoietic stem cells, as well as affects the proportion of immune cells in the peripheral system. Animal studies show that mice loss of LXN promotes tumor growth in subcutaneous tumor model and AOM/DSS-induced colorectal cancer model. We found that loss of LXN promotes macrophage M2 polarization and PD-L2 expression in macrophage, thus, inhibits the function of T cells. Adoptive transfer of wild-type macrophage rescues the function of T cells in LXN-deficient mice. LXN deficiency in hematopoietic lineage exacerbates colorectal carcinogenesis, and targeted inhibition of PD-L2 ameliorates cancer growth in LXN-deficient mice. Mechanistically, we demonstrate that LXN inhibits STAT3 transcriptional activity by targeting inhibition of JAK1 in macrophages. LXN deficiency enhances PD-L2 expression rather than PD-L1 in macrophages, which lead to inhibition of T cells in tumor microenvironment. Collectively, we define a critical role of LXN/JAK1/STAT3 signal in macrophage and highlights the potential role of LXN in tumor immune-escape by regulating macrophage polarization, as well as the expression of immune checkpoint PD-L2.
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A hydroxamic acid based microtubule-destabilizing agent (MDA) SKLB-14b was discovered in this study, which was derived from shortening the linker length of the HDAC6 and microtubule dual-target inhibitor SKLB-23bb. SKLB-14b exhibited low nanomolar IC50 values on a wide spectrum of human cancer cell lines including both sensitive and multidrug-resistant cell lines. Surprisingly, its anti-proliferative activity relied on the presence of the hydroxamic acid group but lost inhibitory activity against HDACs. SKLB-14b bound to the colchicine site of tubulin and could inhibit tubulin polymerization. It exhibited good metabolic stability in liver microsomes, no inhibitory effect on CYP450 isoenzymes and high oral bioavailability. In vivo experiments revealed that SKLB-14b was potent in both sensitive (A2780S, HCT116) and resistant (A2780/T) xenograft mice models. Furthermore, in the patient-derived tumor xenograft (PDX) models of osimertinib resistant non-small cell lung cancer (NSCLC), 50 mg/kg of SKLB-14b administered every twodays inhibited tumor growth by 70.6% without obvious toxicity, better than the 59.7% inhibition rate of paclitaxel. Mechanistically, we found that SKLB-14b exerted anti-tumor and anti-multidrug resistance effects in vitro and in vivo through cell cycle arrest and pro-apoptotic activities, as well as vascular disrupting activities. Therefore, we discovered that SKLB-14b, as a novel MDA based on hydroxamic acid, could serve as a potential drug candidate for cancer therapy which deserves further investigation.
Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias Ovarianas , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Ácidos Hidroxâmicos/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Microtúbulos , Neoplasias Ovarianas/tratamento farmacológico , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Yes-associated protein (YAP) has been identified as a key driver for epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) resistance. Inhibition of YAP expression could be a potential therapeutic option for treating non-small-cell lung cancer (NSCLC). Herein, a nanococktail therapeutic strategy is proposed by employing amphiphilic and block-dendritic-polymer-based nanoparticles (NPs) for targeted co-delivery of EGFR-TKI gefitinib (Gef) and YAP-siRNA to achieve a targeted drug/gene/photodynamic therapy. The resulting NPs are effectively internalized into Gef-resistant NSCLC cells, successfully escape from late endosomes/lysosomes, and responsively release Gef and YAP-siRNA in an intracellular reductive environment. They preferentially accumulate at the tumor site after intravenous injection in both cell-line-derived xenograft (CDX) and patient-derived xenograft (PDX) models of Gef-resistant NSCLC, resulting in potent antitumor efficacy without distinct toxicity after laser irradiation. Mechanism studies reveal that the cocktail therapy could block the EGFR signaling pathway with Gef, inhibit activation of the EGFR bypass signaling pathway via YAP-siRNA, and induce tumor cell apoptosis through photodynamic therapy (PDT). Furthermore, this combination nanomedicine can sensitize PDT and impair glycolysis by downregulating HIF-1α. These results suggest that this stimuli-responsive dendritic-polymer-based nanococktail therapy may provide a promising approach for the treatment of EGFR-TKI resistant NSCLC.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Fotoquimioterapia , Polímeros Responsivos a Estímulos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Preparações Farmacêuticas , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , RNA Interferente Pequeno/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Obesity is a risk factor for many chronic diseases, and is associated with increased incidence rate of type 2 diabetes, hypertension, dyslipidemia and cardiovascular diseases. Adipocyte differentiation play critical role during development of obesity. Latexin (LXN), a mammalian carboxypeptidase inhibitor, plays important role in the proliferation and differentiation of stem cells, and highlights as a differentiation-associated gene that was significantly downregulated in prostate stem cells and whose expression increases through differentiation. However, it is unclear whether LXN is involved in adipocyte differentiation. The aim of this study was to evaluate the role of LXN on adipocyte differentiation, as well as its effects on high fat-induced obesity and metabolic disorders. In this study, we determine the expression of LXN in adipose tissue of lean and fat mice by Western blot, qPCR and immunohistochemistry. We found that LXN in fat tissues was continuous increased during the development of diet-induced obesity. We fed wild-type (WT) and LXN-/-mice with high-fat diet (HFD) to study the effects of LXN on obesity and related metabolic functions. We found that mice deficient in LXN showed resistance against high-fat diet (HFD)-induced obesity, glucose tolerance, insulin tolerance and hepatic steatosis. In vitro studies indicated that LXN was highly induced during adipocyte differentiation, and positively regulated adipocyte differentiation and adipogenesis in 3T3-L1 cells and primary preadipocytes. Functional analysis revealed that the expression of LXN was positively regulated by mTOR/RXR/PPARɤ signaling pathway during the differentiation of adipocytes, while LXN deletion decreased the protein level of PPARɤ in adipocyte through enhancing FABP4 mediated ubiquitination, which led to impaired adipocyte differentiation and lipogenesis. Collectively, our data provide evidence that LXN is a key positive regulator of adipocyte differentiation, and therapeutics targeting LXN could be effective in preventing obesity and its associated disorders in clinical settings.
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Diabetes Mellitus Tipo 2 , Doenças Metabólicas , Células 3T3-L1 , Adipócitos/metabolismo , Adipogenia/genética , Animais , Diferenciação Celular , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Masculino , Mamíferos , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Obesidade/metabolismo , PPAR gama/metabolismoRESUMO
Synaptotagmins (SYTs), constitute a family of 17 membrane-trafficking protein, palying crucial roles in the development and progression of human cancers. However, only very few studies have investigated the expression profile and prognostic values of SYTs family members in gastric cancer (GC). Therefore, we comprehensively evaluated the expression, methylation, prognosis and immune significance of SYTs family members through bioinformatics analysis from the online databases in GC. The expressions of SYT4, SYT9, and SYT14 were up-regulated, and negatively associated with their methylation levels in GC. Both the over-expression of SYT4, SYT9 and SYT14 and their hypomethylation levels contributed to an unsatisfactory overall survival (OS) and progression-free survival (PFS) in GC. Moreover, the low expressions of several methylation cg sites (cg02795029, cg07581146, cg15149095, cg19922137, cg25371503, cg26158959, cg02269161, cg03226737, cg08185661, cg16437728, cg22723056 and cg24678137) were significantly correlated with an unfavorable OS and PFS in GC. Furthermore, the expression of SYT4, SYT9 and SYT14 played a pivotal role in immune cells infiltration in GC. Collectively, our current finding suggested that SYT4, SYT9 and SYT14 might be potent prognostic indictors and promising immunotherapeutic targets for GC patients.
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Metilação de DNA/genética , Neoplasias Gástricas , Sinaptotagminas/genética , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidade , Sinaptotagminas/química , Sinaptotagminas/metabolismo , Transcriptoma/genéticaRESUMO
The aim of this study was to investigate how mesenchymal stromal cells (MSCs) modulate metabolic balance and attenuate hepatic lipotoxicity in the context of non-alcoholic fatty liver disease (NAFLD). In vivo, male SD rats were fed with high-fat diet (HFD) to develop NAFLD; then, they were treated twice by intravenous injections of rat bone marrow MSCs. In vitro, HepG2 cells were cocultured with MSCs by transwell and exposed to palmitic acid (PA) for 24 hours. The endoplasmic reticulum (ER) stressor thapsigargin and sarco/ER Ca2+ -ATPase (SERCA2)-specific siRNA were used to explore the regulation of ER stress by MSCs. We found that MSC administration improved hepatic steatosis, restored systemic hepatic lipid and glucose homeostasis, and inhibited hepatic ER stress in HFD-fed rats. In hepatocytes, MSCs effectively alleviated the cellular lipotoxicity. Particularly, MSCs remarkably ameliorated the ER stress and intracellular calcium homeostasis induced by either PA or thapsigargin in HepG2 cells. Additionally, long-term HFD or PA stimulation would activate pyroptosis in hepatocytes, which may contribute to the cell death and liver dysfunction during the process of NAFLD, and MSC treatment effectively ameliorates these deleterious effects. SERCA2 silencing obviously abolished the ability of MSCs against the PA-induced lipotoxicity. Conclusively, our study demonstrated that MSCs were able to ameliorate liver lipotoxicity and metabolic disturbance in the context of NAFLD, in which the regulation of ER stress and the calcium homeostasis via SERCA has played a key role.
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Comunicação Celular , Estresse do Retículo Endoplasmático , Hepatócitos/metabolismo , Células-Tronco Mesenquimais/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Animais , Biomarcadores , Cálcio/metabolismo , Linhagem Celular , Células Cultivadas , Citocinas/metabolismo , Dieta Hiperlipídica , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Hepatócitos/ultraestrutura , Homeostase , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos , Masculino , Transplante de Células-Tronco Mesenquimais , Ácido Palmítico/metabolismo , Ácido Palmítico/farmacologia , RatosRESUMO
Objective: Patient-derived xenograft (PDX) models have shown great promise in preclinical and translational applications, but their consistency with primary tumors in phenotypic, genetic, and pharmacodynamic heterogeneity has not been well-studied. This study aimed to establish a PDX repository for non-small cell lung cancer (NSCLC) and to further elucidate whether it could preserve the heterogeneity within and between tumors in patients. Methods: A total of 75 surgically resected NSCLC specimens were implanted into immunodeficient NOD/SCID mice. Based on the successful establishment of the NSCLC PDX model, we compared the expressions of vimentin, Ki67, EGFR, and PD-L1 proteins between cancer tissues and PDX models using hematoxylin and eosin staining and immunohistochemical staining. In addition, we detected whole gene expression profiling between primary tumors and PDX generations. We also performed whole exome sequencing (WES) analysis in 17 first generation xenografts to further assess whether PDXs retained the patient heterogeneities. Finally, paclitaxel, cisplatin, doxorubicin, atezolizumab, afatininb, and AZD4547 were used to evaluate the responses of PDX models to the standard-of-care agents. Results: A large collection of serially transplantable PDX models for NSCLC were successfully developed. The histology and pathological immunohistochemistry of PDX xenografts were consistent with the patients' tumor samples. WES and RNA-seq further confirmed that PDX accurately replicated the molecular heterogeneities of primary tumors. Similar to clinical patients, PDX models responded differentially to the standard-of-care treatment, including chemo-, targeted- and immuno-therapeutics. Conclusions: Our established PDX models of NSCLC faithfully reproduced the molecular, histopathological, and therapeutic characteristics, as well as the corresponding tumor heterogeneities, which provides a clinically relevant platform for drug screening, biomarker discovery, and translational research.
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Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Animais , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Gold nanoparticles (AuNPs) have shown great promise in various biomedical applications, but their effects on male reproductive function remain to be ascertained. The aim of this study was to investigate the uptake, cytotoxicity and testosterone production inhibition of AuNPs in mouse Leydig cells, as well as their accumulation in the testes of male mice and their effects on male reproductive function. RESULTS: AuNPs (5 nm) were able to be internalized into the endosomes/lysosomes of TM3 Leydig cells, induce the formation of autophagosomes, increase the production of reactive oxygen species (ROS), and disrupt the cell cycle in S phase, resulting in concentration-dependent cytotoxicity and DNA damage. Interestingly, AuNPs significantly reduced testosterone production in TM3 cells by inhibiting the expression of 17α-hydroxylase, an important enzyme in androgen synthesis. After repeated intravenous injection, AuNPs gradually accumulated and retained in the testes of male BALB/c mice in a dose-dependent manner. One week after withdrawal, the level of plasma testosterone in the 0.5 mg/kg AuNPs group was significantly reduced compared to that in the PBS control group, accompanied by the decreased expression of 17α-hydroxylase in the testes. In addition, AuNPs treatment significantly increased the rate of epididymal sperm malformation, but without affecting fertility. CONCLUSION: Our results suggest that AuNPs can accumulate in the testes and reduce testosterone production in Leydig cells by down-regulating the expression of 17α-hydroxylase, thus affecting the quality of epididymal sperm.
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Ouro/química , Ouro/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Nanopartículas Metálicas/química , Reprodução/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Espécies Reativas de Oxigênio/metabolismo , Espermatozoides/metabolismo , Testículo/citologia , Testículo/metabolismo , Testículo/fisiologia , Testosterona/biossínteseRESUMO
Chirality plays a very important role in medicine, biochemistry and other fields. Because the enantiomers of chiral drugs often show different pharmacology activity, metabolism, and toxicity, therefore, the recognition of chiral molecules is very important, and has become a hot spot and frontier of modern chemical research. In this paper, a new method for recognizing chiral molecular based on naphthalimide dye(NA)âcucurbit[5]uril(CB[7]) assembly is developed. NA as guest can be combined with the host CB[7] to form a 1:1 NAâCB[7] assembly. Furthermore, this assembly was used as a fluorescent probe to recognize D/L-phenylalanine and D/L-phenylalaninol by fluorescence titration. When D-phenylalanine or D-phenylalaninol was added to NAâCB[7] assembly, the fluorescent intensity of assembly was partially quenched, but when L-phenylalanine or L-phenylalaninol was added to NAâCB[7], the fluorescence intensity of the assembly almost unchanged. Herein, chiral recognition platform based on achiral NAâachiral CB[7] was constructed.
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Hidrocarbonetos Aromáticos com Pontes/química , Corantes Fluorescentes/química , Imidazóis/química , Naftalimidas/química , Fenilalanina/análogos & derivados , Fenilalanina/análise , Corantes Fluorescentes/síntese química , Conformação Molecular , EstereoisomerismoRESUMO
In recent years, studies have found that E2F1, a downstream effector of caveolin-1 (Cav-1), participates in tumor cell metabolic reprogramming. E2F1 modulates mitochondrial fusion and mitophagy. Bioinformatic analysis has identified the E2F1-MFN2 axis as a regulator of mitophagy. Our data establish a new novel paradigm for regulation of the tumor cell metabolic reprogramming pathway by Cav-1 that is operationally linked and mutually dependent on the transcriptional activation of E2F1 and induces mitophagy with BNIP3 in cancer-associated fibroblasts (CAFs).
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Fibroblastos Associados a Câncer , Neoplasias , Fibroblastos Associados a Câncer/metabolismo , Caveolina 1 , Fator de Transcrição E2F1/metabolismo , Humanos , Pulmão , Proteínas de Membrana/metabolismo , Mitofagia , Proteínas Proto-Oncogênicas/metabolismoRESUMO
Iron oxide nanoparticles (IONPs) have shown great potential in various biomedical applications. However, information on the interaction between IONPs and biological systems, especially the uptake and distribution of IONPs in cells and tissues, as well as the mechanism of biological action, is relatively limited. In the present study, multi-modal visualization methods, including confocal fluorescence microscopy, transmission electron microscopy, magnetic resonance imaging, and fluorescence optical imaging, were utilized to unveil the uptake and distribution of IONPs in macrophages, cancer cells, and xenograft models. Our results demonstrated that uptake of IONPs in RAW264.7 macrophages and SKOV-3 cancer cells were dose- and cell type-dependent. Cellular uptake of IONPs was an energy-dependent process, and caveolae-mediated endocytosis was the main uptake pathway. All the IONPs were primarily present in endocytic compartments (e.g., endosomes, lysosomes) inside the cells. At 48 hours after intravenous injection of IONPs in SKOV-3 tumor bearing mice, most of the IONPs was distributed in the liver and spleen, with obvious uptake in the tumor, less but significant amount in the kidney and brain. Taken together, multi-modal visualization approaches in our study provide detailed information on the cellular uptake and tissue distribution of IONPs from multiple levels and perspectives.
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Nanopartículas , Animais , Compostos Férricos , Xenoenxertos , Macrófagos , CamundongosRESUMO
PURPOSE: It is demonstrated that unsaturated fatty acids can counteract saturated fatty acids-induced lipotoxicity, but the molecular mechanisms are unclear. In this study, we investigated the protective effects of monounsaturated oleic acid (OA) against saturated palmitic acid (PA)-induced cytotoxicity in rat ß cells as well as islets, and mechanistically focused on its regulation on endoplasmic reticulum (ER) stress. METHODS: Rat insulinoma cell line INS-1E cells and primary islets were treated with PA with or without OA for 24 h to determine the cell viability, apoptosis, and ER stress. SD rats were fed with high-fat diet (HFD) for 16 w, then, HFD was half replaced by olive oil to observe the protective effects of monounsaturated fatty acids rich diet. RESULTS: We demonstrated that PA impaired cell viability and insulin secretion of INS-1E cells and rat islets, but OA robustly rescued cells from cell death. OA substantially alleviated either PA or chemical ER stressors (thapsigargin or tunicamycin)-induced ER stress. Importantly, OA attenuated the activity of PERK-eIF2α-ATF4-CHOP pathway and regulated the ER Ca2+ homeostasis. In vivo, only olive oil supplementation did not cause significant changes, while high-fat diet (HFD) for 32 w obviously induced islets ER stress and impaired insulin sensitivity in SD rats. Half replacement of HFD with olive oil (a mixed diet) has ameliorated this effect. CONCLUSION: OA alleviated PA-induced lipotoxicity in INS-1E cells and improved insulin sensitivity in HFD rats. The amelioration of PA triggered ER stress may be responsible for its beneficial effects in ß cells.
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Estresse do Retículo Endoplasmático/efeitos dos fármacos , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Ácido Oleico/farmacologia , Ácido Palmítico/farmacologia , Animais , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glucose/farmacologia , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Gold nanoparticles (AuNPs) have shown great promise in biomedical applications. However, the interaction of AuNPs with biological systems, its underlying mechanisms and influencing factors need to be further elucidated. PURPOSE: The aim of this study was to systematically investigate the effects of particle size on the uptake and cytotoxicity of AuNPs in normal cells and cancer cells as well as their biological distribution in vivo. RESULTS: Our data demonstrated that the uptake of AuNPs increased in HepG2 cancer cells but decreased in L02 normal cells, with the increase of particle size (5-50 nm). In both cancer cells and normal cells, small (5 nm) AuNPs exhibited greater cytotoxicity than large ones (20 and 50 nm). Interestingly, 5 nm AuNPs induced both apoptosis and necrosis in HepG2 cells through the production of reactive oxygen species (ROS) and the activation of pro-caspase3, whereas it mainly induced necrosis in L02 cells through the overexpression of TLR2 and the release of IL-6 and IL-1a cytokines. Among them, 50 nm AuNPs showed the longest blood circulation and highest distribution in liver and spleen, and the treatment of 5 nm AuNPs but not 20 nm and 50 nm AuNPs resulted in the increase of neutrophils and slight hepatotoxicity in mice. CONCLUSION: Our results indicate that the particle size of AuNPs and target cell type are critical determinants of cellular uptake, cytotoxicity and underlying mechanisms, and biological distribution in vivo, which deserves careful consideration in the future biomedical applications.
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Ouro/farmacologia , Nanopartículas Metálicas/efeitos adversos , Nanopartículas Metálicas/química , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Citocinas/metabolismo , Hemólise/efeitos dos fármacos , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Distribuição Tecidual , Testes de ToxicidadeRESUMO
Aim This study aims to demonstrate the protective effects of monounsaturated oleic acid (OA) against saturated palmitic acid (PA) induced cellular lipotoxicity in hepatocytes and rats with non-alcoholic steatohepatitis (NASH). MAIN METHODS: Human hepatoma cell line HepG2 cells and neonatal rat primary hepatocytes were treated with PA or/and OA for 24â¯h. SD rats were fed with high fat diet (HFD) to induce NASH. From the 16th w, the HFD was full or half replaced by olive oil to observe the protective effects. KEY FINDINGS: In vitro, OA substantially alleviated PA induced cellular apoptosis, oxidative stress, ER stress, mitochondrial dysfunction, as well as inflammation in hepatocytes. In vivo, only olive oil supplementation had no detrimental effects, while HFD developed NASH in normal rats. Full replacement of HFD with olive oil had profoundly reversed NASH. Noteworthily, half replacement of HFD with olive oil (a mixed diet) has ameliorated NASH injury as well. It strikingly changed the hepatic histology from macrovesicular-steatosis into entire microvesicular-steatosis, and significantly reduced inflammation, ballooning and fibrosis. SIGNIFICANCE: Our study has demonstrated in both hepatocytes and NASH rats that oleic acids had great potential to combat the saturated fatty acids induced hepatic lipotoxicity. Only half replacement of HFD by monounsaturated fatty acids rich diet still had significant therapeutic outcome in NASH rats. Redirecting the toxic saturated fatty acids into triglyceride storage and reduction of cholesterol accumulation might be the possible explanation of OA driven protection in this scenario.
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Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/toxicidade , Hepatócitos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ácido Oleico/farmacologia , Substâncias Protetoras/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Masculino , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
In this work, the interfacial properties of a series of metal-free organic naphthodithienothiophene (NDTT)-based photosensitizers adsorbed on TiO2 surfaces were investigated by a combination of ab initio calculations and experimental measurements. The calculations and experiments reveal that because of the efficient charge transfer from the adsorbed dyes to TiO2 nanocrystal surface there is an upward shift for the energy levels of dyes and a downward shift for the conduction band of surface TiO2 and that the band gaps for both of them are also reduced. Such electronic level alignments at the interface would lead to increased light absorption range by adsorbed dyes and increased driving force for charge injection but reduced open-circuit potential (V(oc)). More interestingly, we found that molecule engineering of the donor group and introducing additional electron-withdrawing unit have little effect on the electronic level alignments at the interface (because band gaps of the dyes adsorbed on TiO2 surfaces become approximately identical when compared with those of the dyes measured in solution) but that they can affect the steric effect and the charge separation at the interface to tune V(oc) and the short-circuit current density (J(sc)) effectively. All these findings suggest that optimizing the interfacial properties of dyes adsorbed on TiO2 surfaces by synchronously modifying steric effects of dye molecules anchored on TiO2 and charge-transfer and separation properties at the interfaces is important to construct efficient dye-sensitized solar cells.