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1.
FASEB J ; 38(8): e23603, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38648368

ABSTRACT

Recent evidence suggests that chronic exposure to opioid analgesics such as morphine disrupts the intestinal epithelial layer and causes intestinal dysbiosis. Depleting gut bacteria can preclude the development of tolerance to opioid-induced antinociception, suggesting an important role of the gut-brain axis in mediating opioid effects. The mechanism underlying opioid-induced dysbiosis, however, remains unclear. Host-produced antimicrobial peptides (AMPs) are critical for the integrity of the intestinal epithelial barrier as they prevent the pathogenesis of the enteric microbiota. Here, we report that chronic morphine or fentanyl exposure reduces the antimicrobial activity in the ileum, resulting in changes in the composition of bacteria. Fecal samples from morphine-treated mice had increased levels of Akkermansia muciniphila with a shift in the abundance ratio of Firmicutes and Bacteroidetes. Fecal microbial transplant (FMT) from morphine-naïve mice or oral supplementation with butyrate restored (a) the antimicrobial activity, (b) the expression of the antimicrobial peptide, Reg3γ, (c) prevented the increase in intestinal permeability and (d) prevented the development of antinociceptive tolerance in morphine-dependent mice. Improved epithelial barrier function with FMT or butyrate prevented the enrichment of the mucin-degrading A. muciniphila in morphine-dependent mice. These data implicate impairment of the antimicrobial activity of the intestinal epithelium as a mechanism by which opioids disrupt the microbiota-gut-brain axis.


Subject(s)
Analgesics, Opioid , Dysbiosis , Fentanyl , Gastrointestinal Microbiome , Intestinal Mucosa , Mice, Inbred C57BL , Morphine , Animals , Morphine/pharmacology , Mice , Dysbiosis/chemically induced , Dysbiosis/microbiology , Gastrointestinal Microbiome/drug effects , Intestinal Mucosa/metabolism , Intestinal Mucosa/drug effects , Intestinal Mucosa/microbiology , Male , Fentanyl/pharmacology , Analgesics, Opioid/pharmacology , Brain-Gut Axis/drug effects , Fecal Microbiota Transplantation , Pancreatitis-Associated Proteins/metabolism , Akkermansia/drug effects , Antimicrobial Peptides/pharmacology , Bacteroidetes/drug effects
2.
Small ; : e2310012, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368250

ABSTRACT

Developing efficient nonprecious bifunctional electrocatalysts for hydrogen and oxygen evolution reactions (HER and OER) in the same electrolyte with a low overpotential and large current density presents an appealing yet challenging goal for large-scale water electrolysis. Herein, a unique 3D self-branched hierarchical nanostructure composed of ultra-small cobalt phosphide (CoP) nanoparticles embedded into N, P-codoped carbon nanotubes knitted hollow nanowall arrays (CoPʘNPCNTs HNWAs) on carbon textiles (CTs) through a carbonization-phosphatization process is presented. Benefiting from the uniform protrusion distributions of CoP nanoparticles, the optimum CoPʘNPCNTs HNWAs composites with high abundant porosity exhibit superior electrocatalytic activity and excellent stability for OER in alkaline conditions, as well as for HER in both acidic and alkaline electrolytes, even under large current densities. Furthermore, the assembled CoPʘNPCNTs/CTs||CoPʘNPCNTs/CTs electrolyzer demonstrates exceptional performance, requiring an ultralow cell voltage of 1.50 V to deliver the current density of 10 mA cm-2 for overall water splitting (OWS) with favorable stability, even achieving a large current density of 200 mA cm-2 at a low cell voltage of 1.78 V. Density functional theory (DFT) calculation further reveals that all the C atoms between N and P atoms in CoPʘNPCNTs/CTs act as the most efficient active sites, significantly enhancing the electrocatalytic properties. This strategy, utilizing 2D MOF arrays as a structural and compositional material to create multifunctional composites/hybrids, opens new avenues for the exploration of highly efficient and robust non-noble-metal catalysts for energy-conversion reactions.

3.
J Exp Bot ; 75(1): 123-136, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37724960

ABSTRACT

Lignin and cellulose are two essential elements of plant secondary cell walls that shape the mechanical characteristics of the culm to prevent lodging. However, how the regulation of the lignin and cellulose composition is combined to achieve optimal mechanical characteristics is unclear. Here, we show that increasing OsTCP19 expression in rice coordinately repressed lignin biosynthesis and promoted cellulose biosynthesis, resulting in enhanced lodging resistance. In contrast, repression of OsTCP19 coordinately promoted lignin biosynthesis and inhibited cellulose biosynthesis, leading to greater susceptibility to lodging. We found that OsTCP19 binds to the promoters of both MYB108 and MYB103L to increase their expression, with the former being responsible for repressing lignin biosynthesis and the latter for promoting cellulose biosynthesis. Moreover, up-regulation of OsTCP19 in fibers improved grain yield and lodging resistance. Thus, our results identify the OsTCP19-OsMYB108/OsMYB103L module as a key regulator of lignin and cellulose production in rice, and open up the possibility for precisely manipulating lignin-cellulose composition to improve culm mechanical properties for lodging resistance.


Subject(s)
Lignin , Oryza , Lignin/metabolism , Oryza/metabolism , Cellulose/metabolism , Carbohydrate Metabolism , Cell Wall/metabolism
4.
Exp Eye Res ; 243: 109902, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38641196

ABSTRACT

Nitrogen mustard (NM) is a potent vesicating chemical warfare agent that is primarily absorbed through skin, inhalation, or ocular surface. Ocular exposure of NM can cause acute to chronic keratopathy which can eventually lead to blindness. There is a current lack of effective countermeasures against ocular exposure of NM despite their imperative need. Herein, we aim to explore the sustained effect of Dexamethasone sodium phosphate (DSP)-loaded polymeric nanoparticles (PLGA-DSP-NP) following a single subconjunctival injection in the management and prevention of corneal injury progression upon exposure to NM. DSP is an FDA approved corticosteroid with proven anti-inflammatory properties. We formulated PLGA-DSP-NP with zinc chelation ion bridging method using PLGA polymer, with particles of approximately 250 nm and a drug loading of 6.5 wt%. Under in vitro sink conditions, PLGA-DSP-NP exhibited a sustained drug release for two weeks. Notably, in NM injured cornea, a single subconjunctival (SCT) injection of PLGA-DSP-NP outperformed DSP eyedrops (0.1%), DSP solution, placebo NP, and saline, significantly mitigating corneal neovascularization, ulceration, and opacity for the two weeks study period. Through PLGA-DSP-NP injection, sustained DSP release hindered inflammatory cytokine recruitment, angiogenic factors, and endothelial cell proliferation in the cornea. This strategy presents a promising localized corticosteroid delivery system to effectively combat NM-induced corneal injury, offering insights into managing vesicant exposure.


Subject(s)
Dexamethasone , Mechlorethamine , Nanoparticles , Dexamethasone/analogs & derivatives , Animals , Mechlorethamine/toxicity , Disease Models, Animal , Corneal Injuries/prevention & control , Corneal Injuries/chemically induced , Corneal Injuries/pathology , Corneal Injuries/drug therapy , Glucocorticoids , Chemical Warfare Agents/toxicity , Mice , Burns, Chemical/prevention & control , Burns, Chemical/drug therapy , Eye Burns/chemically induced , Eye Burns/prevention & control , Rabbits , Cornea/drug effects , Cornea/pathology , Cornea/metabolism
5.
Biochem Biophys Res Commun ; 656: 1-9, 2023 05 14.
Article in English | MEDLINE | ID: mdl-36940637

ABSTRACT

Sorafenib has been used to enhance the survival outcome of hepatocellular carcinoma (HCC) patients. But, occurrence resistance to sorafenib subtracts from its therapeutic benefits. Herein, we identified that FOXM1 was markedly upregulated in both tumor samples and sorafenib-resistant HCC tissues. We also demonstrated that patients with decreased FOXM1 expression had longer overall survival (OS) and progression-free survival (PFS) in the cohort of sorafenib-treated patients. For HCC cells resistant to sorafenib, the IC50 value of sorafenib and the expression of FOXM1 were increased. In addition, Downregulation of FOXM1 expression alleviated the occurrence of resistance to sorafenib and reduced the proliferative potential and viability of HCC cells. Mechanically, the suppression of the FOXM1 gene resulted in the downregulation of KIF23 levels. Moreover, downregulation of FOXM1 expression reduced the levels of RNA polymerase II (RNA pol II) and histone H3 lysine 27 acetylation (H3K27ac) on the KIF23 promoter, further epigenetically silencing the production of KIF23. More intriguingly, our results similarly revealed that FDI-6, a specific inhibitor of FOXM1, suppressed the proliferation of HCC cells resistant to sorafenib, as well as upregulation of FOXM1 or KIF23 abolished this effect. In addition, we found that FDI-6 combined with sorafenib significantly improved the therapeutic effect of sorafenib. Collectively, the present results revealed that FOXM augments sorafenib resistance and enhances HCC progression by upregulating KIF23 expression via an epigenetic mechanism, and targeting FOXM1 can be an effective treatment for HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Sorafenib/pharmacology , Sorafenib/therapeutic use , Liver Neoplasms/drug therapy , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Up-Regulation , Transcriptional Activation , Drug Resistance, Neoplasm/genetics , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Cell Proliferation , Forkhead Box Protein M1/genetics , Forkhead Box Protein M1/metabolism , Microtubule-Associated Proteins/metabolism
6.
Mol Pharm ; 20(4): 2207-2216, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36938947

ABSTRACT

Pulmonary deposition of lung-targeted therapeutic aerosols can achieve direct drug delivery to the site of action, thereby enhancing the efficacy and reducing systemic exposure. In this study, we investigated the in vitro and in vivo aerosol performance of the novel small animal air-jet dry powder insufflator (Rat AJ DPI) using spray-dried albuterol excipient-enhanced-growth (EEG) powder as a model formulation. The in vitro aerosolization performance of the optimized albuterol EEG powder was first assessed using the Rat AJ DPI. The performance of Rat AJ DPI to deliver albuterol EEG aerosol to rat lungs was then compared to that of the Penn-Century Insufflator. Albuterol EEG powders dispersed using the Rat AJ DPI demonstrated narrow unimodal aerosol size distribution profiles, which were independent of the loaded powder dose (1, 2, and 5 mg). In addition, the span value for Rat AJ DPI (5 mg powder mass) was 1.32, which was 4.2-fold lower than that for Penn-Century insufflator (5 mg powder mass). At a higher loaded mass of 5 mg, the Rat AJ DPI delivered significantly larger doses to rat lungs compared with the Penn-Century DPI. The Rat AJ DPI with hand actuation delivered approximately 85% of the total emitted dose (2 and 5 mg loadings), which was comparatively higher than that for Penn-Century DPI (approximately 75%). In addition, percentage deposition in each of the lung lobes for the Rat AJ DPI was observed to be independent of the administration dose (2 and 5 mg loadings) with coefficients of variation below 12%, except in the right middle lobe. Automatic actuation of a 5 mg powder mass using the Rat AJ DPI demonstrated a similar delivered dose compared to manual actuation of the same dose, with 82% of the total emitted dose reaching the lung lobes. High-efficiency delivery of the aerosol to the lobar lung region and low sensitivity of the interlobar delivery efficiency to the loaded dose highlight the suitability of the new air-jet DPI for administering therapeutic pharmaceutical aerosols to small test animals.


Subject(s)
Albuterol , Dry Powder Inhalers , Animals , Rats , Powders , Aerosols , Administration, Inhalation , Excipients , Particle Size , Lung
7.
Hepatobiliary Pancreat Dis Int ; 22(1): 34-40, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36513566

ABSTRACT

BACKGROUND: Tumor recurrence after liver transplantation (LT) for selective patients diagnosed with hepatocellular carcinoma (HCC) in the setting of cirrhosis is the greatest challenge effecting the prognosis of these patients. The aim of this study was to evaluate the efficacy of sirolimus on the prognosis for these recipients. METHODS: The data from 193 consecutive HCC patients who had undergone LT from January 2015 to December 2019 were retrospectively analyzed. These patients were divided into the sirolimus group [patients took sirolimus combined with calcineurin inhibitors (CNIs) (n = 125)] and non-sirolimus group [patients took CNI-based therapy without sirolimus (n = 68)]. Recurrence-free survival (RFS) and overall survival (OS) were compared between the two groups. The prognostic factors and independent risk factors for RFS and OS were further evaluated. RESULTS: Non-sirolimus was an independent risk factor for RFS (HR = 2.990; 95% CI: 1.050-8.470; P = 0.040) and OS (HR = 3.100; 95% CI: 1.190-8.000; P = 0.020). A higher proportion of patients beyond Hangzhou criteria was divided into the sirolimus group (69.6% vs. 80.9%, P = 0.030). Compared with the non-sirolimus group, the sirolimus group had significantly better RFS (P < 0.001) and OS (P < 0.001). Further subgroup analysis showed similar results. CONCLUSIONS: This study demonstrated that sirolimus significantly decreased HCC recurrence and prolonged RFS and OS in LT patients with different stage of HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/surgery , Sirolimus/adverse effects , Liver Neoplasms/pathology , Retrospective Studies , Neoplasm Recurrence, Local , Prognosis
8.
Am J Respir Cell Mol Biol ; 64(1): 69-78, 2021 01.
Article in English | MEDLINE | ID: mdl-33095650

ABSTRACT

Mucus obstruction is a key feature of many inflammatory airway diseases. Neutrophil extracellular traps (NETs) are released upon neutrophil stimulation and consist of extracellular chromatin networks studded with cytotoxic proteins. When released in the airways, these NETs can become part of the airway mucus. We hypothesized that the extracellular DNA and/or oxidative stress (e.g., by the release of reactive oxygen species and myeloperoxidase during NETs formation in the airways) would increase mucus viscoelasticity. We collected human airway mucus from endotracheal tubes of healthy patients admitted for elective surgery and coincubated these samples with NETs from phorbol 12-myristate 13-acetate-stimulated neutrophils. Unstimulated neutrophils served as controls, and blocking experiments were performed with dornase alfa for extracellular DNA and the free radical scavenger dimethylthiourea for oxidation. Compared with controls, the coincubation of mucus with NETs resulted in 1) significantly increased mucus viscoelasticity (macrorheology) and 2) significantly decreased mesh pore size of the mucus and decreased movement of muco-inert nanoparticles through the mucus (microrheology), but 3) NETs did not cause visible changes in the microstructure of the mucus by scanning EM. Incubation with either dornase alfa or dimethylthiourea attenuated the observed changes in macrorheology and microrheology. This suggests that the release of NETs may contribute to airway mucus obstruction by increasing mucus viscoelasticity and that this effect is not solely due to the release of DNA but may in part be due to oxidative stress.


Subject(s)
Extracellular Traps/immunology , Mucus/immunology , Neutrophils/immunology , Respiratory System/immunology , Adult , Airway Obstruction/immunology , Airway Obstruction/metabolism , Extracellular Traps/metabolism , Humans , Mucus/metabolism , Neutrophils/metabolism , Oxidative Stress/immunology , Peroxidase/immunology , Peroxidase/metabolism , Reactive Oxygen Species/immunology , Reactive Oxygen Species/metabolism , Respiratory System/metabolism
9.
Biochem Biophys Res Commun ; 585: 185-190, 2021 12 31.
Article in English | MEDLINE | ID: mdl-34808502

ABSTRACT

Hepatocellular carcinoma (HCC) is a prevalent solid cancer worldwide and sorafenib is a common treatment. Nevertheless, sorafenib resistance is a severe clinical problem. In the present study, we identified that epigenetic regulator, KAT6A, was overexpressed in clinical HCC tissues and sorafenib-resistant HCC samples. The depletion of KAT6A repressed the cell viability and Edu-positive cell numbers of HCC cells. The IC50 value of sorafenib was increased in sorafenib-resistant HCC cells. In addition, the expression of KAT6A was induced in sorafenib-resistant HCC cells. The depletion of KAT6A suppressed the IC50 of sorafenib. Mechanically, YAP was decreased by the depletion of KAT6A. KAT6A was able to enrich in the promoter of YAP. The silencing of KAT6A reduced the enrichment of histone H3 lysine 23 acetylation (H3K23ac) and RNA polymerase II (RNA pol II) on the promoter of YAP in sorafenib-resistant HCC cells. KAT6A inhibitor WM-1119 repressed the cell proliferation of sorafenib-resistant HCC cells, while overexpression of KAT6A or YAP could reverse the effect in the cells. Meanwhile, the treatment of sorafenib inhibited the viability of sorafenib-resistant HCC cells, while the co-treatment of WM-1119 could improve the effect of sorafenib. Collectively, KAT6A was associated with sorafenib resistance and contributes to progression of HCC by targeting YAP. Targeting KAT6A may be served as a promising therapeutic approach for HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Cell Cycle Proteins/genetics , Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Histone Acetyltransferases/genetics , Liver Neoplasms/genetics , Sorafenib/pharmacology , Transcription Factors/genetics , Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Cell Survival/genetics , Disease Progression , Epigenesis, Genetic , Hep G2 Cells , Histone Acetyltransferases/metabolism , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/metabolism
10.
AAPS PharmSciTech ; 22(1): 42, 2021 Jan 10.
Article in English | MEDLINE | ID: mdl-33426616

ABSTRACT

In vitro release studies are commonly used to assess the product performance of topical dosage forms. In such studies, the mass transport of drugs through synthetic membranes into a receiving chamber filled with a release medium is measured. The release medium is also passed through filtration membranes prior to chromatographic analysis. There are no official guidelines directing membrane selection for in vitro release studies or for filtration. Considering the diversity in membrane materials and their physical properties, the aim of this study was to investigate membrane-drug binding and the effect of various membranes on the release performance of a model drug dexamethasone (DEX) using USP dissolution apparatus IV. Seven membranes of different pore sizes (0.45 and 1.2 µm) and materials (cellulose acetate, polyethersulfone, and nylon) were assessed. Two different methods, syringe filter and 24-h incubation, were used for the determination of membrane-drug binding effects at low drug concentrations and saturated concentration conditions. Cellulose acetate and nylon membranes showed significant drug binding after 24-h incubations at both drug concentrations. DEX diffusion through membranes was significantly slowed down in all the tested membranes when compared with DEX solution without membranes. The extent of the retardation varied due to the differences in membrane structures. In conclusion, materials and sources of membranes affected drug dissolution profiles and the results showed membrane-drug binding effects. Proper selection of membranes with low drug binding ability and low diffusion resistance is essential to ensure appropriate and reproducible in vitro release assessments and filtration studies. Graphical Abstract.


Subject(s)
Dexamethasone/chemistry , Drug Liberation , Diffusion , Filtration , Membranes, Artificial
11.
Int J Cancer ; 146(6): 1754-1763, 2020 03 15.
Article in English | MEDLINE | ID: mdl-31456215

ABSTRACT

To explore whether plasma circular RNAs (circRNAs) can diagnose hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), microarray and qPCR were used to identify plasma circRNAs that were increased in HBV-related HCC patients compared to controls (including healthy controls, chronic hepatitis B and HBV-related liver cirrhosis). A logistic regression model was constructed using a training set (n = 313) and then validated using another two independent sets (n = 306 and 526, respectively). Area under the receiver operating characteristic curve (AUC) was used to evaluate diagnostic accuracy. We identified a plasma circRNA panel (CircPanel) containing three circRNAs (hsa_circ_0000976, hsa_circ_0007750 and hsa_circ_0139897) that could detect HCC. CircPanel showed a higher accuracy than AFP (alpha-fetoprotein) to distinguish individuals with HCC from controls in all three sets (AUC, 0.863 [95% confidence interval, CI: 0.819-0.907] vs. 0.790 [0.738-0.842], p = 0.036 in training set; 0.843 [0.796-0.890] vs. 0.747 [0.691-0.804], p = 0.011 in validation set 1 and 0.864 [0.830-0.898] vs. 0.769 [0.728-0.810], p < 0.001 in validation set 2). CircPanel also performed well in detecting Small-HCC (solitary, ≤3 cm), AFP-negative HCC and AFP-negative Small-HCC.


Subject(s)
Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/etiology , Hepatitis B virus , Hepatitis B/complications , Liver Neoplasms/diagnosis , Liver Neoplasms/etiology , RNA, Circular/blood , Biomarkers, Tumor , Female , Gene Expression Profiling , Hepatitis B/virology , Humans , Male , Polymerase Chain Reaction , ROC Curve , Reproducibility of Results
12.
Nanomedicine ; 29: 102262, 2020 10.
Article in English | MEDLINE | ID: mdl-32623017

ABSTRACT

Tenacious sputum poses a critical diffusion barrier for aerosol antibiotics used to treat cystic fibrosis (CF) lung infection. We conducted a proof-of-concept study using dense poly(ethylene glycol) coated polystyrene nanoparticles (PS-PEG NPs) as model muco-inert particles (MIPs) formulated as a powder using an excipient enhanced growth (EEG) strategy, aiming to minimize extrathoracic airway loss, maximize deposition in the airway and further overcome the sputum barrier in the CF lungs. The EEG aerosol formulation containing PS-PEG MIPs was prepared by spray drying and produced discrete spherical particles with geometric diameter of approximately 2 µm; and >80% of the powder dose was delivered from a new small-animal dry powder inhaler (DPI). The MIPs released from the EEG aerosol had human airway mucus and CF sputum diffusion properties comparable to the suspension formulation. These properties make this formulation a promising pulmonary drug delivery system for CF lung infections.


Subject(s)
Cystic Fibrosis/drug therapy , Drug Delivery Systems , Lung Diseases/drug therapy , Lung/drug effects , Nanoparticles/chemistry , Administration, Inhalation , Cystic Fibrosis/pathology , Dry Powder Inhalers/methods , Excipients/chemistry , Humans , Lung/growth & development , Lung Diseases/pathology , Mucus/drug effects , Polyethylene Glycols/chemistry , Polyethylene Glycols/pharmacology , Polystyrenes/chemistry , Polystyrenes/pharmacology
13.
Proc Natl Acad Sci U S A ; 114(18): E3719-E3728, 2017 05 02.
Article in English | MEDLINE | ID: mdl-28416692

ABSTRACT

Müller glia (MG) function as inducible retinal stem cells in zebrafish, completely repairing the eye after damage. The innate immune system has recently been shown to promote tissue regeneration in which classic wound-healing responses predominate. However, regulatory roles for leukocytes during cellular regeneration-i.e., selective cell-loss paradigms akin to degenerative disease-are less well defined. To investigate possible roles innate immune cells play during retinal cell regeneration, we used intravital microscopy to visualize neutrophil, macrophage, and retinal microglia responses to induced rod photoreceptor apoptosis. Neutrophils displayed no reactivity to rod cell loss. Peripheral macrophage cells responded to rod cell loss, as evidenced by morphological transitions and increased migration, but did not enter the retina. Retinal microglia displayed multiple hallmarks of immune cell activation: increased migration, translocation to the photoreceptor cell layer, proliferation, and phagocytosis of dying cells. To test function during rod cell regeneration, we coablated microglia and rod cells or applied immune suppression and quantified the kinetics of (i) rod cell clearance, (ii) MG/progenitor cell proliferation, and (iii) rod cell replacement. Coablation and immune suppressants applied before cell loss caused delays in MG/progenitor proliferation rates and slowed the rate of rod cell replacement. Conversely, immune suppressants applied after cell loss had been initiated led to accelerated photoreceptor regeneration kinetics, possibly by promoting rapid resolution of an acute immune response. Our findings suggest that microglia control MG responsiveness to photoreceptor loss and support the development of immune-targeted therapeutic strategies for reversing cell loss associated with degenerative retinal conditions.


Subject(s)
Ependymoglial Cells/immunology , Immunity, Innate , Immunomodulation , Regeneration/immunology , Retinal Rod Photoreceptor Cells/physiology , Zebrafish/immunology , Animals , Ependymoglial Cells/pathology , Humans , Retinal Rod Photoreceptor Cells/pathology
14.
AAPS PharmSciTech ; 22(1): 8, 2020 Nov 25.
Article in English | MEDLINE | ID: mdl-33241486

ABSTRACT

While drug-loaded microparticles (MPs) can serve as drug reservoirs for sustained drug release and therapeutic effects, needle clogging by MPs poses a challenge for ocular drug delivery via injection. Two polymers commonly used in ophthalmic procedures-hyaluronic acid (HA) and methylcellulose (MC)-have been tested for their applicability for ocular injections. HA and MC were physically blended with sunitinib malate (SUN)-loaded PLGA MPs for subconjunctival (SCT) injection into rat eyes. The HA and MC viscous solutions facilitated injection through fine-gauged needles due to their shear-thinning properties as shown by rheological characterizations. The diffusion barrier presented by HA and MC reduced burst drug release and extended overall release from MPs. The significant level of MP retention in the conjunctiva tissue post-operation confirmed the minimal leakage of MPs following injection. The safety of HA and MC for ocular applications was demonstrated histologically.


Subject(s)
Conjunctiva , Microspheres , Viscosity , Administration, Ophthalmic , Animals , Delayed-Action Preparations , Drug Delivery Systems , Polylactic Acid-Polyglycolic Acid Copolymer/administration & dosage , Rats
15.
Proteomics ; 19(21-22): e1800451, 2019 11.
Article in English | MEDLINE | ID: mdl-31231915

ABSTRACT

The targeting of glutamine metabolism specifically via pharmacological inhibition of glutaminase 1 (GLS1) has been translated into clinical trials as a novel therapy for several cancers. The results, though encouraging, show room for improvement in terms of tumor reduction. In this study, the glutaminase II pathway is found to be upregulated for glutamate production upon GLS1 inhibition in pancreatic tumors. Moreover, genetic suppression of glutamine transaminase K (GTK), a key enzyme of the glutaminase II pathway, leads to the complete inhibition of pancreatic tumorigenesis in vivo unveiling GTK as a new metabolic target for cancer therapy. These results suggest that current trials using GLS1 inhibition as a therapeutic approach targeting glutamine metabolism in cancer should take into account the upregulation of other metabolic pathways that can lead to glutamate production; one such pathway is the glutaminase II pathway via GTK.


Subject(s)
Enzyme Inhibitors/pharmacology , Glutaminase/genetics , Lyases/genetics , Pancreatic Neoplasms/drug therapy , Transaminases/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Glutamic Acid/metabolism , Glutaminase/antagonists & inhibitors , Glutamine/genetics , Glutamine/metabolism , Humans , Lyases/antagonists & inhibitors , Metabolic Networks and Pathways/drug effects , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Transaminases/antagonists & inhibitors
16.
J Hepatol ; 70(5): 904-917, 2019 05.
Article in English | MEDLINE | ID: mdl-30654066

ABSTRACT

BACKGROUND & AIMS: Genetic variability in the hepatitis B virus X gene (HBx) is frequently observed and is associated with hepatocellular carcinoma (HCC) progression. However, a genotype classification based on the full-length HBx sequence and the impact of genotypes on hepatitis B virus (HBV)-related HCC prognosis remain unclear. We therefore aimed to perform this genotype classification and assess its clinical impact. METHODS: We classified the genotypes of the full-length HBx gene through sequencing and a cluster analysis of HBx DNA from a cohort of patients with HBV-related HCC, which served as the primary cohort (n = 284). Two independent HBV-related HCC cohorts, a validation cohort (n = 171) and a serum cohort (n = 168), were used to verify the results. Protein microarray assay analysis was performed to explore the underlying mechanism. RESULTS: In the primary cohort, the HBx DNA was classified into 3 genotypes: HBx-EHBH1, HBx-EHBH2, and HBx-EHBH3. HBx-EHBH2 (HBx-E2) indicated better recurrence-free survival and overall survival for patients with HCC. HBx-E2 was significantly correlated with the absence of liver cirrhosis, a small tumor size, a solitary tumor, complete encapsulation and Barcelona Clinic Liver Cancer (BCLC) stage A-0 tumors. Additionally, HBx-E2 served as a significant prognostic factor for patients with BCLC stage B HCC after hepatectomy. Mechanistically, HBx-E2 is unable to promote proliferation in HCC cells and normal hepatocytes. It also fails to activate the Janus kinase 1 (JAK1)/signal transducer and activator of transcription 3 (STAT3)/STAT5 pathway. CONCLUSION: Our study identifies a novel HBx genotype that is unable to promote the proliferation of HCC cells and suggests a potential marker to preoperatively predict the prognosis of patients with BCLC stage B, HBV-associated, HCC. LAY SUMMARY: We classified a novel genotype of the full-length hepatitis B virus X gene (HBx), HBx-E2. This genotype was identified in tumor and nontumor tissues from patients with hepatitis B virus-related hepatocellular carcinoma. HBx-E2 could preoperatively predict the prognosis of patients with intermediate stage hepatocellular carcinoma, after resection.


Subject(s)
Carcinoma, Hepatocellular/genetics , Janus Kinase 1/physiology , Liver Neoplasms/genetics , STAT Transcription Factors/physiology , Trans-Activators/genetics , Viral Regulatory and Accessory Proteins/genetics , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Cell Line, Tumor , Genotype , Humans , Liver Neoplasms/mortality , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Neoplasm Staging , Prognosis , Signal Transduction/physiology , Trans-Activators/blood , Trans-Activators/classification , Viral Regulatory and Accessory Proteins/blood , Viral Regulatory and Accessory Proteins/classification
17.
Mol Pharm ; 16(5): 1958-1970, 2019 05 06.
Article in English | MEDLINE | ID: mdl-30912953

ABSTRACT

Fenofibrate is a peroxisome proliferator-activated receptor α (PPARα) agonist and has been shown to have therapeutic effects on diabetic retinopathy (DR). However, the effects of fenofibrate through systemic administration are not as potent as desired due to inefficient drug delivery to the retina. The present study aimed to explore the sustained therapeutic effects of fenofibrate-loaded biodegradable nanoparticles (NP) on both DR and neovascular age-related macular degeneration (AMD). Fenofibrate was successfully encapsulated into poly(lactic- co-glycolic acid) (PLGA) NP (Feno-NP), and Feno-NP were optimized by varying polymer composition to achieve high drug loading and prolonged drug release. The Feno-NP made of PLGA 34 kDa demonstrated a drug content of 6% w/w and a sustained drug release up to 60 days in vitro. Feno-NP (PLGA 34 kDa) was selected for following in vivo studies, and one single intravitreal (IVT) injection of Feno-NP into rat eyes with a 30G fine needle maintained sustained fenofibric acid drug level in the eye for more than 60 days. The efficacy of Feno-NP in DR and neovascular AMD was investigated using streptozotocin (STZ)-induced diabetic rats, laser-induced choroidal neovascularization (CNV) rats, and very low-density lipoprotein receptor knockout ( Vldlr -/-) mice. Therapeutic effects of Feno-NP were evaluated by measuring electroretinogram (ERG), retinal vascular leakage, leukostasis, CNV size, and retinal levels of vascular endothelial growth factor (VEGF) and intracellular adhesion molecule-1 (ICAM-1). In diabetic rats, Feno-NP ameliorated retinal dysfunctions, reduced retinal vascular leakage, inhibited retinal leukostasis, and downregulated the overexpression of VEGF and ICAM-1 at 8 weeks after one IVT injection. In addition, Feno-NP reduced retinal vascular leakage and CNV formation in both CNV rats and Vldlr -/- mice. Moreover, no toxicity of Feno-NP or Blank-NP to retinal structure and function was detected. Feno-NP exhibited good physiochemical characteristics and controlled drug release profile, conferring prolonged beneficial effects on DR and neovascular AMD.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/drug therapy , Drug Delivery Systems/methods , Fenofibrate/analogs & derivatives , Hypolipidemic Agents/therapeutic use , Nanoparticles/chemistry , Wet Macular Degeneration/drug therapy , Animals , Capillary Permeability , Choroidal Neovascularization/drug therapy , Diabetes Mellitus, Experimental/chemically induced , Drug Liberation , Fenofibrate/chemistry , Fenofibrate/pharmacokinetics , Fenofibrate/therapeutic use , Hypolipidemic Agents/chemistry , Intercellular Adhesion Molecule-1/metabolism , Leukostasis/drug therapy , Mice , Mice, Knockout , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Rats , Rats, Inbred BN , Retina/drug effects , Retina/metabolism , Streptozocin/adverse effects , Streptozocin/pharmacology , Tissue Distribution , Vascular Endothelial Growth Factor A/metabolism
18.
Nanomedicine ; 17: 119-123, 2019 04.
Article in English | MEDLINE | ID: mdl-30677499

ABSTRACT

Corneal neovascularization (CNV) leads to the loss of corneal transparency and vision impairment, and can ultimately cause blindness. Topical corticosteroids are the first line treatment for suppressing CNV, but poor ocular bioavailability and rapid clearance of eye drops makes frequent administration necessary. Patient compliance with frequent eye drop application regimens is poor. We developed biodegradable nanoparticles (NP) loaded with dexamethasone sodium phosphate (DSP) using zinc ion bridging, DSP-Zn-NP, with dense coatings of poly(ethylene glycol) (PEG). DSP-Zn-NP were safe and capable of providing sustained delivery of DSP to the front of the eye following subconjunctival (SCT) administration in rats. We reported that a single SCT administration of DSP-Zn-NP prevented suture-induced CNV in rats for two weeks. In contrast, the eyes receiving SCT administration of either saline or DSP solution developed extensive CNV in less than 1 week. SCT administration of DSP-Zn-NP could be an effective strategy in preventing and treating CNV.


Subject(s)
Corneal Neovascularization/prevention & control , Delayed-Action Preparations/chemistry , Dexamethasone/analogs & derivatives , Glucocorticoids/administration & dosage , Zinc/chemistry , Animals , Dexamethasone/administration & dosage , Dexamethasone/therapeutic use , Glucocorticoids/therapeutic use , Nanoparticles/chemistry , Polyethylene Glycols/chemistry , Rats
19.
Acta Biochim Biophys Sin (Shanghai) ; 51(3): 285-292, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30883648

ABSTRACT

Hepatocellular carcinoma (HCC) is one of the most aggressive cancers worldwide. Identification of the molecular mechanisms underlying the development and progression of HCC is particularly important. Here, we demonstrated the expression pattern, clinical significance, and function of Karyopherin α2 (KPNA2) in HCC. The expression of KPNA2 was upregulated in tumor tissue and negatively associated with the survival time, and a significant correlation between KPNA2 expression and aggressive clinical characteristics was established. Both in vitro and in vivo experiments demonstrated that knockdown of KPNA2 reduced migration and proliferation capacities of HCC cells, while over-expression of KPNA2 increased these malignant characteristics. The analysis of the Cancer Genome Atlas cohorts also reveals that high-KPNA2 expression is associated with poor outcome in multiple cancer types. In addition, gene sets enrichment analysis exhibited cell cycle and DNA replication as the top altered pathways in the high-KPNA2 expression group in HCC and other two cancer types. Overall, this study identified KPNA2 as a potential diagnostic and prognostic biomarker in HCC and other neoplasms, probably by regulating cell cycle and DNA replication.


Subject(s)
Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , alpha Karyopherins/physiology , Adult , Aged , Animals , Carcinoma, Hepatocellular/mortality , Cell Line, Tumor , Cell Movement , Cell Proliferation , Disease Progression , Humans , Liver Neoplasms/mortality , Mice , Middle Aged , Prognosis , Up-Regulation , alpha Karyopherins/genetics
20.
Proc Natl Acad Sci U S A ; 113(36): E5328-36, 2016 09 06.
Article in English | MEDLINE | ID: mdl-27559084

ABSTRACT

Targeting glutamine metabolism via pharmacological inhibition of glutaminase has been translated into clinical trials as a novel cancer therapy, but available drugs lack optimal safety and efficacy. In this study, we used a proprietary emulsification process to encapsulate bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES), a selective but relatively insoluble glutaminase inhibitor, in nanoparticles. BPTES nanoparticles demonstrated improved pharmacokinetics and efficacy compared with unencapsulated BPTES. In addition, BPTES nanoparticles had no effect on the plasma levels of liver enzymes in contrast to CB-839, a glutaminase inhibitor that is currently in clinical trials. In a mouse model using orthotopic transplantation of patient-derived pancreatic tumor tissue, BPTES nanoparticle monotherapy led to modest antitumor effects. Using the HypoxCR reporter in vivo, we found that glutaminase inhibition reduced tumor growth by specifically targeting proliferating cancer cells but did not affect hypoxic, noncycling cells. Metabolomics analyses revealed that surviving tumor cells following glutaminase inhibition were reliant on glycolysis and glycogen synthesis. Based on these findings, metformin was selected for combination therapy with BPTES nanoparticles, which resulted in significantly greater pancreatic tumor reduction than either treatment alone. Thus, targeting of multiple metabolic pathways, including effective inhibition of glutaminase by nanoparticle drug delivery, holds promise as a novel therapy for pancreatic cancer.


Subject(s)
Metformin/administration & dosage , Nanoparticles/administration & dosage , Pancreatic Neoplasms/drug therapy , Sulfides/administration & dosage , Thiadiazoles/administration & dosage , Animals , Antineoplastic Combined Chemotherapy Protocols , Benzeneacetamides/therapeutic use , Cell Line, Tumor , Glutaminase/antagonists & inhibitors , Glutamine/metabolism , Humans , Mice , Nanoparticles/chemistry , Pancreatic Neoplasms/enzymology , Pancreatic Neoplasms/pathology , Proto-Oncogene Proteins p21(ras)/genetics , Sulfides/chemistry , Thiadiazoles/chemistry , Thiadiazoles/therapeutic use , Xenograft Model Antitumor Assays
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