RESUMO
ALK-positive NSCLC patients demonstrate initial responses to ALK tyrosine kinase inhibitor (TKI) treatments, but eventually develop resistance, causing rapid tumor relapse and poor survival rates. Growing evidence suggests that the combination of drug and immune therapies greatly improves patient survival; however, due to the low immunogenicity of the tumors, ALK-positive patients do not respond to currently available immunotherapies. Tumor-associated macrophages (TAMs) play a crucial role in facilitating lung cancer growth by suppressing tumoricidal immune activation and absorbing chemotherapeutics. However, they can also be programmed toward a pro-inflammatory tumor suppressive phenotype, which represents a highly active area of therapy development. Iron loading of TAMs can achieve such reprogramming correlating with an improved prognosis in lung cancer patients. We previously showed that superparamagnetic iron oxide nanoparticles containing core-cross-linked polymer micelles (SPION-CCPMs) target macrophages and stimulate pro-inflammatory activation. Here, we show that SPION-CCPMs stimulate TAMs to secrete reactive nitrogen species and cytokines that exert tumoricidal activity. We further show that SPION-CCPMs reshape the immunosuppressive Eml4-Alk lung tumor microenvironment (TME) toward a cytotoxic profile hallmarked by the recruitment of CD8+ T cells, suggesting a multifactorial benefit of SPION-CCPM application. When intratracheally instilled into lung cancer-bearing mice, SPION-CCPMs delay tumor growth and, after first line therapy with a TKI, halt the regrowth of relapsing tumors. These findings identify SPIONs-CCPMs as an adjuvant therapy, which remodels the TME, resulting in a delay in the appearance of resistant tumors.
Assuntos
Crizotinibe , Neoplasias Pulmonares , Nanopartículas Magnéticas de Óxido de Ferro , Microambiente Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Microambiente Tumoral/efeitos dos fármacos , Animais , Nanopartículas Magnéticas de Óxido de Ferro/química , Humanos , Camundongos , Crizotinibe/farmacologia , Crizotinibe/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Linhagem Celular Tumoral , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo , Proliferação de Células/efeitos dos fármacos , FemininoRESUMO
Improving target versus off-target ratio in nanomedicine remains a major challenge for increasing drug bioavailability and reducing toxicity. Active targeting using ligands on nanoparticle surfaces is a key approach but has limited clinical success. A potential issue is the integration of targeting ligands also changes the physicochemical properties of nanoparticles (passive targeting). Direct studies to understand the mechanisms of active targeting and off-targeting in vivo are limited by the lack of suitable tools. Here, the biodistribution of a representative active targeting liposome is analyzed, modified with an apolipoprotein E (ApoE) peptide that binds to the low-density lipoprotein receptor (LDLR), using zebrafish embryos. The ApoE liposomes demonstrated the expected liver targeting effect but also accumulated in the kidney glomerulus. The ldlra-/- zebrafish is developed to explore the LDLR-specificity of ApoE liposomes. Interestingly, liver targeting depends on the LDLR-specific interaction, while glomerular accumulation is independent of LDLR and peptide sequence. It is found that cationic charges of peptides and the size of liposomes govern glomerular targeting. Increasing the size of ApoE liposomes can avoid this off-targeting. Taken together, the study shows the potential of the zebrafish embryo model for understanding active and passive targeting mechanisms, that can be used to optimize the design of nanoparticles.
Assuntos
Apolipoproteínas E , Lipossomos , Peptídeos , Receptores de LDL , Peixe-Zebra , Animais , Lipossomos/química , Receptores de LDL/metabolismo , Peptídeos/química , Apolipoproteínas E/metabolismo , Embrião não Mamífero/metabolismo , Nanopartículas/químicaRESUMO
Epalrestat, an aldose reductase inhibitor (ARI), has been clinically adopted in treating diabetic neuropathy in China and Japan. Apart from the involvement in diabetic complications, AR has been implicated in inflammation. Here, we seek to investigate the feasibility of clinically approved ARI, epalrestat, for the treatment of rheumatoid arthritis (RA). The mRNA level of AR was markedly upregulated in the peripheral blood mononuclear cells (PBMCs) of RA patients when compared to those of healthy donors. Besides, the disease activity of RA patients is positively correlated with AR expression. Epalrestat significantly suppressed lipopolysaccharide (LPS) induced TNF-α, IL-1ß, and IL-6 in the human RA fibroblast-like synoviocytes (RAFLSs). Unexpectedly, epalrestat treatment alone markedly exaggerated the disease severity in adjuvant induced arthritic (AIA) rats with elevated Th17 cell proportion and increased inflammatory markers, probably resulting from the increased levels of 4-hydroxy-2-nonenal (4-HNE) and malondialdehyde (MDA). Interestingly, the combined treatment of epalrestat with N-Acetylcysteine (NAC), an anti-oxidant, to AIA rats dramatically suppressed the production of 4-HNE, MDA and inflammatory cytokines, and significantly improved the arthritic condition. Taken together, the anti-arthritic effect of epalrestat was diminished or even overridden by the excessive accumulation of toxic 4-HNE or other reactive aldehydes in AIA rats due to AR inhibition. Co-treatment with NAC significantly reversed epalrestat-induced upregulation of 4-HNE level and potentiated the anti-arthritic effect of epalrestat, suggesting that the combined therapy of epalrestat with NAC may sever as a potential approach in treating RA. Importantly, it could be regarded as a safe intervention for RA patients who need epalrestat for the treatment of diabetic complications.
Assuntos
Acetilcisteína , Artrite Reumatoide , Humanos , Animais , Ratos , Acetilcisteína/uso terapêutico , Leucócitos Mononucleares , Aldeídos , Artrite Reumatoide/tratamento farmacológicoRESUMO
Objective: This study aimed to investigate the diagnostic performance of volume mismatch sign on discriminating paramedial bithalamic tumors from non-tumors. Methods: In this study, we recruited patients with tumors or non-tumors of the paramedial bithalamus. We confirmed the diagnosis by pathology, laboratory tests documented in medical records, medical imaging at the baseline, or through at least 1 year of follow-up. Cases with paramedial thalamic lesions on only one side or purely midbrain illnesses were excluded. Additionally, any case without involvement of the medial thalami (i.e., those with one or both-sided anterior, lateral, or posterior thalamic lesions) was excluded. Two neuroradiologists were trained independently to evaluate volume mismatch sign on magnetic resonance T2-weighted images or T2 fluid-attenuated inversion recovery images. A positive volume mismatch sign means that the ratio of the larger-sided lesion volume to the smaller-sided lesion volume is >150%. The volume of each lesion was calculated by multiplying the anteroposterior diameter by the left-right diameter and by the height of the lesion and then dividing by 2. The kappa value was calculated to show the consistency between the two observers. The chi-square test was used to evaluate differences in volume mismatch sign between the bilthalamic midline tumor and non-tumor groups. The positive (PPV) and negative (NPV) predictive values, sensitivity, and specificity were calculated to evaluate the ability of volume mismatch sign to differentiate paramedial bilateral thalamus tumors from non-tumors. A two-tailed P ≤ 0.05 was considered to be statistically significant. The analyses were performed using the statistical software SPSS version 26. Results: A total of 96 patients were enrolled in this study between March 2012 and October 2022. A high agreement between the two observers on the volume mismatch sign of bilateral paramedian thalamic diseases was found, and the Kappa value was 0.828. A statistically significant difference was observed for the volume mismatch sign between the paramedial bithalamic tumor and the non-tumorous groups (χ2 = 35.465, P < 0.001). The presence of volume mismatch sign in paramedial bithalamic illnesses predicted the presence of tumors with a sensitivity and specificity of 69.2% and 90.9%, respectively, and PPV and NPV were 90.0% and 71.4%. Conclusion: Volume mismatch sign may indicate tumors in paramedian bithalamic diseases.
RESUMO
To expand the single-dose duration over which noninvasive clinical and preclinical cancer imaging can be conducted with high sensitivity, and well-defined spatial and temporal resolutions, a facile strategy to prepare ultrasmall nanoparticulate X-ray contrast media (nano-XRCM) as dual-modality imaging agents for positron emission tomography (PET) and computed tomography (CT) has been established. Synthesized from controlled copolymerization of triiodobenzoyl ethyl acrylate and oligo(ethylene oxide) acrylate monomers, the amphiphilic statistical iodocopolymers (ICPs) could directly dissolve in water to afford thermodynamically stable solutions with high aqueous iodine concentrations (>140 mg iodine/mL water) and comparable viscosities to conventional small molecule XRCM. The formation of ultrasmall iodinated nanoparticles with hydrodynamic diameters of ca. 10 nm in water was confirmed by dynamic and static light scattering techniques. In a breast cancer mouse model, in vivo biodistribution studies revealed that the 64Cu-chelator-functionalized iodinated nano-XRCM exhibited extended blood residency and higher tumor accumulation compared to typical small molecule imaging agents. PET/CT imaging of tumor over 3 days showed good correlation between PET and CT signals, while CT imaging allowed continuous observation of tumor retention even after 10 days post-injection, enabling longitudinal monitoring of tumor retention for imaging or potentially therapeutic effect after a single administration of nano-XRCM.
RESUMO
Objective:To analyze the consistency of pepsin assay kit, pepsin IHC, reflux symptom indexï¼RSIï¼ and reflux finding scoreï¼RFSï¼ in the diagnosis of laryngopharyngeal reflux diseaseï¼LPRDï¼. Methods:The clinical data of 61 inpatients with laryngeal diseases who were admitted to the Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University from May 2020 to December 2021 were retrospectively analyzed. The RSI and RFS scores, the Formwitz score of pepsin immunohistochemistry, and the results of pepsin detection kit were recorded. ICC group correlation coefficient and Kappa consistency analysis was used for three detection methods. Results:Among 61 patients, 30 cases were positive and 31 cases were negative for the pepsin test kit, with a positive rate of 49.18%. The positive rate of pepsin immunohistochemistry was 45.90%ï¼28/61ï¼, and the diagnostic agreement rate between the two was 70.49%. The consistency between them was highï¼κ=0.409ï¼. The positive rate of RSI and RFS in diagnosing LPRD was 62.30%ï¼38/61ï¼, and the consistency rate was 73.77% with pepsin detection kit. The consistency between them was highï¼κ=0.486ï¼. Taking pepsin IHC as the reference standard, the sensitivity, specificity, positive predictive value and negative predictive value of pepsin detection kit were 71.43%ï¼20/28ï¼, 69.70%ï¼23/33ï¼, 66.67%ï¼20/30ï¼ and 74.19%ï¼23/31ï¼, respectively. Using RSI and RFS scales as reference criteria, the sensitivity, specificity, positive predictive value and negative predictive value of pepsin detection kit were 89.29%ï¼25/28ï¼, 60.61%ï¼20/33ï¼, 65.79%ï¼25/38ï¼ and 86.96%ï¼20/23ï¼, respectively. Analysis of correlation coefficient within ICC group: ICC value was 0.628, 95% confidence intervalï¼0.497-0.741ï¼, the three methods have good consistency. Conclusion:The RSI and RFS scale scores were in good agreement with the pepsin test kit, and the pepsin test kit was also in good agreement with pepsin immunohistochemistry. As a non-invasive diagnostic technique, the pepsin test kit can be widely used in the diagnosis of pharyngeal reflux in combination with pepsin immunohistochemistry and RSI and RFS scale.
Assuntos
Refluxo Laringofaríngeo , Humanos , Refluxo Laringofaríngeo/diagnóstico , Pepsina A/análise , Estudos Retrospectivos , Imuno-Histoquímica , FaringeRESUMO
BACKGROUND: As a first-line chemotherapeutic agent, 5-fluorouracil (5-FU) exhibits many side effects, weakening its efficacy in cancer treatment. In this study, we hypothesize that Poria cocos polysaccharides (PCP), a traditional Chinese herbal medicine with various bioactivities and prebiotic effects, might improve the therapeutic effect of 5-FU by restoring the homeostasis of the gut microenvironment and the commensal gut microflora. METHODS: ApcMin/+ mice were employed to evaluate the anti-cancer effect of 5-FU in conjunction with PCP treatment. Body weight and food consumption were monitored weekly. Polyp count was used to assess the anti-cancer effect of PCP and 5-FU. Expressions of mucosal cytokines and gut epithelial junction molecules were measured using qRT-PCR. 16S rRNA gene sequencing of fecal DNAs was used to evaluate the compositional changes of gut microbiota (GM). Transplantation of Lactobacillus johnsonii and Bifidobacterium animalis were performed to verify the prebiotic effects of PCP in improving the efficacy of 5-FU. RESULTS: The results showed that PCP treatment alleviated the weight loss caused by 5-FU treatment and reduced the polyp burden in ApcMin/+ mice. Additionally, PCP treatment eased the cytotoxic effects of 5-FU by reducing the expressions of pro-inflammatory cytokines, increasing the anti-inflammatory cytokines; and significantly improving the gut barriers by enhancing the tight junction proteins and associated adhesion molecules. Furthermore, 16S rRNA gene sequencing data showed that PCP alone or with 5-FU could stimulate the growth of probiotic bacteria (Bacteroides acidifaciens, Bacteroides intestinihominis, Butyricicoccus pullicaecorum, and the genera Lactobacillus, Bifidobacterium, Eubacterium). At the same time, it inhibited the growth of potential pathogens (e.g., Alistipes finegoldii, Alistipes massiliensis, Alistipes putredinis., Citrobacter spp., Desulfovibrio spp., and Desulfovibrio desulfuricans). Moreover, the results showed that transplantation of L.johnsonii and B.animalis effectively reduced the polyp burden in ApcMin/+ mice being treated with 5-FU. CONCLUSION: Our study showed that PCP could effectively improve the anti-cancer effect of 5-FU by attenuating its side effects, modulating intestinal inflammation, improving the gut epithelial barrier, and modulating the gut microbiota of ApcMin/+ mice.
RESUMO
Hyaluronan (HA) is a mucopolysaccharide that naturally exists in all living organisms as the main component of the extracellular matrix. Over the last 30 years, HA has been used as the main ingredient in cosmetic products, eye drops, and medicinal products. It is also taken orally as a health supplement. However, the physiological effect of the ingested HA is not clear. In the current study, the interaction between HA and gut microbiota, and the potential prebiotic effects were investigated. HA was used to treat the C57BL/6 mice for 15 consecutive days, then fecal genomic DNA was extracted from fecal samples for 16S rRNA amplicon sequencing. The results showed that HA could significantly change the composition of gut microbiota (GM), e.g., increased the relative abundance of beneficial bacteria, including short-chain fatty acids (SCFAs)-producing bacteria and xylan/cellulose-degrading bacteria, whereas decreased the relative abundance of potential pathogens including sulfate-reducing bacteria (SRB), inflammation and cancer-related bacteria. The rotarod test was used to evaluate the anti-fatigue effects of HA in C57BL/6 mice. The results showed that HA could lengthen the mice's retention time on the accelerating rotarod. HA increased the concentration of glycogen and superoxide dismutase (SOD) in mice's muscle and liver, whereas decreased the serum concentration of malondialdehyde (MDA). Moreover, the metabolic products of Desulfovibrio vulgaris (MPDV), the model SRB bacteria, showed cytotoxic effects on H9c2 cardiomyocytes in a dosage-dependent manner. MPDV also caused mitochondrial damage by inducing mitochondrial fragmentation, depolarization, and powerless ATP production. Taken together, we show that HA possesses significant prebiotic and anti-fatigue effects in C57BL/6 mice.
RESUMO
Synthetic water-compatible supramolecular polymers based on benzene-1,3,5-tricarboxamides (BTAs) have attracted a lot of interest in recent years, as they are uniquely suited to generate functional multicomponent biomaterials. Their morphologies and intrinsic dynamic behaviour mimic fibrous structures found in nature. Moreover, their modularity allows control of the density of functionalities presented on the surface of the fibres when using functionalized BTA monomers. However, such moieties generally comprise a functionality on only one of three side chains, resulting in lengthy synthetic protocols and limited yields. In this work, we avert the need for desymmetrization of the core by starting from commercially available 5-aminoisophthalic acid. This approach eliminates the statistical reactions and reduces the number of synthetic steps. It also leads to the inversion of the connectivity of one of the amides to the benzene core. By combining spectroscopy, light scattering and cryogenic transmission electron microscopy, we confirm that the inversed amide BTAs (iBTAs) form intermolecular hydrogen bonds and assemble into supramolecular polymers, like previously used symmetrical BTAs, albeit with a slight decrease in water solubility. Solubility problems were overcome by incorporating iBTAs into conventional BTA-based supramolecular polymers. These two-component mixtures formed supramolecular fibres with a morphology and dynamic behaviour similar to BTA-homopolymers. Finally, iBTAs were decorated with a fluorescent dye to demonstrate the synthesis of functional monomers, and to visualize their co-assembly with BTAs. Our results show that functionality can be introduced into supramolecular polymers with monomers that slightly differ in their core structure while maintaining the structure and dynamics of the fibres.
RESUMO
In only a few decades, lithium-ion batteries have revolutionized technologies, enabling the proliferation of portable devices and electric vehicles1, with substantial benefits for society. However, the rapid growth in technology has highlighted the ethical and environmental challenges of mining lithium, cobalt and other mineral ore resources, and the issues associated with the safe usage and non-hazardous disposal of batteries2. Only a small fraction of lithium-ion batteries are recycled, further exacerbating global material supply of strategic elements3-5. A potential alternative is to use organic-based redox-active materials6-8 to develop rechargeable batteries that originate from ethically sourced, sustainable materials and enable on-demand deconstruction and reconstruction. Making such batteries is challenging because the active materials must be stable during operation but degradable at end of life. Further, the degradation products should be either environmentally benign or recyclable for reconstruction into a new battery. Here we demonstrate a metal-free, polypeptide-based battery, in which viologens and nitroxide radicals are incorporated as redox-active groups along polypeptide backbones to function as anode and cathode materials, respectively. These redox-active polypeptides perform as active materials that are stable during battery operation and subsequently degrade on demand in acidic conditions to generate amino acids, other building blocks and degradation products. Such a polypeptide-based battery is a first step to addressing the need for alternative chemistries for green and sustainable batteries in a future circular economy.
Assuntos
Fontes de Energia Elétrica , Eletroquímica , Peptídeos/química , Animais , Bovinos , Linhagem Celular , Sobrevivência Celular , Óxidos N-Cíclicos/química , Camundongos , Osteoblastos/citologia , Oxirredução , Peptídeos/síntese química , Desenvolvimento Sustentável , Viologênios/químicaRESUMO
Ganoderma lucidum (Leyss.Fr.) Karst is one of the well-known medicinal macrofungi all over the world, and mounting researches have focused on the polysaccharides derived from the spores of G. lucidum. In the present study, BALB/c mice (n = 8-10) were administered with crude polysaccharides of G. lucidum spores (CPGS) and the refined polysaccharides of G. lucidum spores (RPGS) for 30 days to investigate their effect on the adaptive immune system. Results showed that CPGS and RPGS displayed diverse effects on the lymphocyte activity in the spleen. The splenocyte proliferation activity upon mitogen was suppressed by CPGS and RPGS, while the NK cell's tumor-killing ability was promoted by CPGS. Both CPGS and RPGS could increase the proportion of naïve T cells in thymus, but only RPGS significantly uplifted the percentage of T cells, as well as the T cell subsets, in peripheral blood, and promoted the activation by upregulating the expression of costimulatory factor CD28. Moreover, 16S sequencing results showed that the effects of CPGS and RPGS were closely related to the regulation of gut microbiota. ß-diversity of the microbiome was evidently changed by CPGS and RPGS. The phytoestrogen/polysaccharide-metabolizing bacteria (Adlercreutzia, Parabacteroides, and Prevotella), and an unclassified Desulfovibrionaceae, were remarkably enriched by CPGS or RPGS, and functions involving carbohydrate metabolism, membrane transport, and lipid metabolism were regulated. Moreover, the enrichments of Adlercreutzia, Prevotella, and Desulfovibrionaceae were positively related to the immune regulation by CPGS and RPGS, while that of Parabacteroides displayed a negative correlation. These findings suggested a promising effect of the polysaccharide from sporoderm-broken spore of G. lucidum in immune regulation to promote health control.
RESUMO
The fast dynamics occurring in natural processes increases the difficulty of creating biomaterials capable of mimicking Nature. Within synthetic biomaterials, water-soluble supramolecular polymers show great potential in mimicking the dynamic behavior of these natural processes. In particular, benzene-1,3,5-tricaboxamide (BTA)-based supramolecular polymers have shown to be highly dynamic through the exchange of monomers within and between fibers, but their suitability as biomaterials has not been yet explored. Herein we systematically study the interactions of BTA supramolecular polymers bearing either tetraethylene glycol or mannose units at the periphery with different biological entities. When BTA fibers were incubated with bovine serum albumin (BSA), the protein conformation was only affected by the fibers containing tetraethylene glycol at the periphery (BTA-OEG4). Coarse-grained molecular simulations showed that BSA interacted with BTA-OEG4 fibers rather than with BTA-OEG4 monomers that are present in solution or that may exchange out of the fibers. Microscopy studies revealed that, in the presence of BSA, BTA-OEG4 retained their fiber conformation although their length was slightly shortened. When further incubated with fetal bovine serum (FBS), both long and short fibers were visualized in solution. Nevertheless, in the hydrogel state, the rheological properties were remarkably preserved. Further studies on the cellular compatibility of all the BTA assemblies and mixtures thereof were performed in four different cell lines. A low cytotoxic effect at most concentrations was observed, confirming the suitability of utilizing functional BTA supramolecular polymers as dynamic biomaterials.
Assuntos
Benzeno , Materiais Biocompatíveis , Benzamidas , PolímerosRESUMO
Side effects of chemotherapy are burning questions for physicians and patients involved in cancers. Ganoderma lucidum is a widely consumed traditional Chinese medicine and edible mushroom with multiple functional properties. The present study aims to investigate the potential of polysaccharides from spore of G. lucidum (SGP) on small intestinal barrier function recovery against paclitaxel (PTX) challenge in a breast cancer mice model and IEC-6 cell line. The 4T1 tumor-bearing mice were treated with PTX together with four-week daily oral administration of SGP. Results indicated that combination of PTX and SGP reversed body weight lost and remolded the histology of small intestine, accompanied with promoted proliferation but suppressed apoptosis in intestinal cells. Intestinal barrier function was enhanced by the combination as indicated by reduced endotoxemia and the up-regulation of tight junction proteins, including Zonula occludens-1 (ZO-1), E-cadherin, ß-catenin and Occludin. The protection of SGP was further confirmed in IEC-6 cells affected by PTX in vitro. The combination treatment prevented PTX-induced apoptosis in IEC-6 by inhibiting microtubule polymerization, and the aforementioned tight junction proteins were also upregulated. These findings suggest a promising protective effect of SGP against small intestinal barrier injury caused by PTX, highlighting its clinical implication against the chemotherapy side effects.
Assuntos
Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Microtúbulos/efeitos dos fármacos , Paclitaxel/toxicidade , Polissacarídeos/farmacologia , Reishi/química , Esporos Fúngicos/química , Animais , Antineoplásicos Fitogênicos/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Mucosa Intestinal/citologia , Camundongos , Camundongos Endogâmicos BALB C , Paclitaxel/antagonistas & inibidores , Polissacarídeos/química , Proteínas de Junções Íntimas/biossíntese , Redução de Peso/efeitos dos fármacosRESUMO
As a rapid, controllable, and easily transferrable approach to the preparation of antimicrobial nanoparticle systems, a one-step, light-driven procedure was developed to produce asymmetric hybrid inorganic-organic nanoparticles (NPs) directly from a homogeneous Ag/polymer mixture. An amphiphilic triblock polymer was designed and synthesized to build biocompatible NPs, consisting of poly(ethylene oxide) (PEO), carboxylic acid-functionalized polyphosphoester (PPE), and poly(l-lactide) (PLLA). Unexpectedly, snowman-like asymmetric nanostructures were subsequently obtained by simply loading silver cations into the polymeric micelles together with purification via centrifugation. With an understanding of the chemistry of the asymmetric NP formation, a controllable preparation strategy was developed by applying UV irradiation. A morphology transition was observed by transmission electron microscopy over the UV irradiation time, from small silver NPs distributed inside the micelles into snowman-like asymmetric NPs, which hold promise for potential antimicrobial applications with their unique two-stage silver release profiles.
Assuntos
Luz , Nanopartículas/química , Polímeros/química , Prata/química , Processos FotoquímicosRESUMO
[This corrects the article DOI: 10.3389/fmicb.2018.03099.].
RESUMO
SREBPs are master regulators of lipid homeostasis and undergo sterol-regulated export from ER to Golgi apparatus for processing and activation via COPII-coated vesicles. While COPII recognizes SREBP through its escort protein SCAP, factor(s) specifically promoting SREBP/SCAP loading to the COPII machinery remains unknown. Here, we show that the ER/lipid droplet-associated protein Cideb selectively promotes the loading of SREBP/SCAP into COPII vesicles. Sterol deprivation releases SCAP from Insig and enhances ER export of SREBP/SCAP by inducing SCAP-Cideb interaction, thereby modulating sterol sensitivity. Moreover, Cideb binds to the guanine nucleotide exchange factor Sec12 to enrich SCAP/SREBP at ER exit sites, where assembling of COPII complex initiates. Loss of Cideb inhibits the cargo loading of SREBP/SCAP, reduces SREBP activation, and alleviates diet-induced hepatic steatosis. Our data point to a linchpin role of Cideb in regulated ER export of SREBP and lipid homeostasis.
Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/fisiologia , Retículo Endoplasmático/fisiologia , Complexo de Golgi/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Esteróis/farmacologia , Animais , Proteínas Reguladoras de Apoptose/genética , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/efeitos dos fármacos , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/fisiologia , Retículo Endoplasmático/efeitos dos fármacos , Complexo de Golgi/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Homeostase , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Transporte Proteico , Proteína de Ligação a Elemento Regulador de Esterol 1/genéticaRESUMO
A zwitterionic polyphosphoester (zPPE), specifically l-cysteine-functionalized poly(but-3-yn-1-yloxy)-2-oxo-1,3,2-dioxaphospholane (zPBYP), has been developed as a poly(ethylene glycol) (PEG) alternative coating material for gold nanoparticles (AuNPs), the most extensively investigated metal nanoparticulate platform toward molecular imaging, photothermal therapy, and drug delivery applications. Thiol-yne conjugation of cysteine transformed an initial azido-terminated and alkynyl-functionalized PBYP homopolymer into zPBYP, offering hydrolytic degradability, biocompatibility, and versatile reactive moieties for installation of a range of functional groups. Despite minor degradation during purification, zPPEs were able to stabilize AuNPs presumably through multivalent interactions between combinations of the side chain zwitterions (thioether and phosphoester groups of the zPPEs with the AuNPs). 31P NMR studies in D2O revealed ca. 20% hydrolysis of the phosphoester moieties of the repeat units had occurred during the workup and purification by aqueous dialysis at pH 3 over ca. 1 d, as observed by the 31P signal of the phosphotriesters resonating at ca. -0.5 to -1.7 shifting downfield to ca. 1.1 to -0.4 ppm, attributed to transformation to phosphates. Further hydrolysis of side chain and backbone units proceeded to an extent of ca. 75% over the next 2 d in nanopure water (pH 5-6). The NMR degradation results were consistent with the broadening and red-shift of the surface plasmon resonance (SPR) observed by UV-vis spectroscopy of the zPPE-coated AuNPs in water over time. All AuNP formulations in this study, including those with citrate, PEG, and zPPE coatings, exhibited negligible immunotoxicity, as determined by cytokine overexpression in the presence of the nanostructures relative to those in cell culture medium. Notably, the zPPE-coated AuNPs displayed superior antifouling properties, as assessed by the extent of cytokine adsorption relative to both the PEGylated and citrate-coated AuNPs. Taken together, the physicochemical and biological evaluations of zPPE-coated AuNPs in conjunction with PEGylated and citrate-coated analogues indicate the promise of zPPEs as favorable alternatives to PEG coatings, with negligible immunotoxicity, good antifouling performance, and versatile reactive groups that enable the preparation of highly tailored nanomaterials for diverse applications.
Assuntos
Plásticos Biodegradáveis/química , Materiais Revestidos Biocompatíveis/química , Nanopartículas Metálicas/química , Adsorção , Animais , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/metabolismo , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/metabolismo , Citocinas/química , Citocinas/metabolismo , Ouro/química , Camundongos , Ligação Proteica , Células RAW 264.7RESUMO
As breast cancer is the leading cause of cancer-related deaths in women population worldwide, ongoing endeavor has been made for alternative regimens with improved efficacy but fewer adverse effects. Recently, active components from the spores of Ganoderma lucidum have attracted much attention for their versatile biological activities owing to the advance in sporoderm-breaking technology. Here, anticancer potential of an extract derived from the sporoderm-breaking spores of G. lucidum (ESG) was explored in a 4T1-breast cancer xenograft mice model. Results showed that ESG was able to suppress 4T1 tumor growth in vivo rather than in vitro. Flowcytometry analysis revealed that ESG could significantly increase both cytotoxic T cell (Tc) population and the ratio of Tc to helper T cell (Th) in peripheral blood of the tumor-bearing mouse; similar promotion on Tc was also found in tumor-infiltrating lymphocyte. Moreover, ESG evidently downregulated the two immune checkpoints, programmed cell death protein-1 (PD-1, in the spleen) and cytotoxic T lymphocyte antigen-4 (CTLA-4, in the tumor), suggesting that ESG could effectively restore the T cell paradigm by recovering the exhaustion status via suppressing the co-inhibitory checkpoints. By 16S rRNA gene sequence analysis on the fecal microbiota, it was found that ESG would remodeling the overall structure of the samples from tumor-bearing mice toward that of the normal counterparts, including 18 genera in 5 phyla, together with regulations on several genes that are responsible for signaling pathways involved in metabolism, cellular processes, and environmental information processing. Collectively, this study demonstrated that ESG would serve as a natural anticancer adjuvant via a restoration on the exhausted Tc, highlighting important clinical implications for the treatment of breast cancer.
Assuntos
Produtos Biológicos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Reishi/química , Esporos Fúngicos/química , Linfócitos T Citotóxicos/efeitos dos fármacos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Produtos Biológicos/química , Antígeno CTLA-4/genética , Antígeno CTLA-4/metabolismo , Linhagem Celular Tumoral , Feminino , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Camundongos Endogâmicos BALB C , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , RNA Ribossômico 16S/genética , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genéticaRESUMO
OBJECTIVE: To demonstrate that certain qualitative amide proton transfer-weighted (APTw) characteristics can provide practical imaging clues for predicting O6-methylguanine-DNA methyltransferase (MGMT) protein expression in primary low- and high-grade gliomas, preoperatively and noninvasively. METHODS: Pathologically confirmed low- and high-grade gliomas with APT data and immunohistochemical (IHC) reports were recruited in this study. The MGMT protein expression status was classified by postsurgery specimen immunostaining. Subjects were divided into two groups, MGMT-positive and MGMT-negative group, according to the immunoreactivity of MGMT protein expression documented in IHC reports. APTw images scanned at 3T magnetic resonance preoperatively were retrospectively analyzed. Two neuroradiologists were trained to evaluate presence of certain APTw features. Kappa value was calculated to show the consistency between the 2 observers. The Mann-Whitney U test was used to evaluate relationships between the 2 groups on APTw features. Negative predictive value and positive predictive value was used to evaluate the ability of APTw characteristics in predicting MGMT protein expression. Receiver operating characteristic curve was used to evaluate the diagnostic performance of APTw characters. Two-tailed P < 0.05 was considered as statistically significant. RESULTS: Forty-two subjects were recruited in this study. Among them 38 specimens presented positive MGMT immunostaining (MGMT-positive group), 4 specimens were negative MGMT immunostaing (MGMT-negative group). There were, respectively, 37 and 5 APTw images appeared positive and negative APTw features. Differences between tumors of positive and negative MGMT expression on qualitative APTw features were significant (P = 0.020). The consistency coefficient of the 2 observers was 0.876 (kappa = 0.876). Three of five llgliomas with negative APTw features showed MGMT-negative immunostaining, leading to a negative predictive value of 60%, and 36 of 37 cases presenting positive APTw characteristics were tumors of MGMT-positive expression, generating a positive predictive value of 97.3%. The area under curve was 0.849. CONCLUSIONS: APTw characteristics could be promising imaging markers by which to predict IHC MGMT expression in primary low- and high-grade gliomas preoperatively and noninvasively.
Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/enzimologia , Metilases de Modificação do DNA/biossíntese , Enzimas Reparadoras do DNA/biossíntese , Glioma/diagnóstico por imagem , Glioma/enzimologia , Imageamento por Ressonância Magnética/métodos , Proteínas Supressoras de Tumor/biossíntese , Adulto , Idoso , Amidas , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/métodos , Valor Preditivo dos Testes , Prótons , Estudos Retrospectivos , Proteínas Supressoras de Tumor/genéticaRESUMO
BACKGROUND: Anomalous diffusion model has been introduced and shown to be beneficial in clinical applications. However, only the directionally averaged values of anomalous diffusion parameters were investigated, and the anisotropy of anomalous diffusion remains unexplored. The aim of this study was to demonstrate the feasibility of using anisotropy of anomalous diffusion for differentiating low- and high-grade cerebral gliomas. METHODS: Diffusion MRI images were acquired from brain tumor patients and analyzed using the fractional motion (FM) model. Twenty-two patients with histopathologically confirmed gliomas were selected. An anisotropy metric for the FM-related parameters, including the Noah exponent (α) and the Hurst exponent (H), was introduced and their values were statistically compared between the low- and high-grade gliomas. Additionally, multivariate logistic regression analysis was performed to assess the combination of the anisotropy metric and the directionally averaged value for each parameter. The diagnostic performances for grading gliomas were evaluated using a receiver operating characteristic (ROC) analysis. RESULTS: The Hurst exponent H was more anisotropic in high-grade than in low-grade gliomas (Pâ¯=â¯0.015), while no significant difference was observed for the anisotropy of α. The ROC analysis revealed that larger areas under the ROC curves were produced for the combination of α (1) and the combination of H (0.813) compared with the directionally averaged α (0.979) and H (0.594), indicating an improved performance for tumor differentiation. CONCLUSION: The anisotropy of anomalous diffusion can provide distinctive information and benefit the differentiation of low- and high-grade gliomas. The utility of anisotropic anomalous diffusion may have an improved effect for investigating pathological changes in tissues.