Reactive oxygen species (ROS) play an important role in cellular metabolism and many oxidative stress related diseases. Oxidative stress results from toxic effects of ROS and plays a critical role in ...the pathogenesis of a variety of diseases like cancers and many important biological processes. It is known that the unique feature of high intracellular ROS level in cancer cells can be considered as target and utilized as a useful cancer‐related stimulus to mediate intracellular drug delivery. Therefore, biomaterials responsive to excess level of ROS are of great importance in biomedical applications. In this study, a novel ROS‐responsive polymer based on L‐methionine poly(ester amide) (Met‐PEA‐PEG) was designed, synthesized, characterized and self‐assembled into nano‐micellar‐type nanoparticles (NP). The Met‐PEA‐PEG NP exhibited responsiveness to an oxidative environment. The size and morphology of the nanoparticle changed rapidly in the presence of H2O2. The Nile Red dye was loaded into the Met‐PEA‐PEG NP to demonstrate a H2O2 concentration induced time‐dependent release behavior. The Met‐PEA‐PEG NP was sensitive to high intracellular ROS level of PC3 prostate cancer cells. Furthermore, the Met‐PEA‐PEG NP was investigated as a carrier of a Chinese medicine‐based anticancer component, gambogic acid (GA). Compared to free GA, the GA‐loaded nanocomplex (GA‐NP) showed enhanced cytotoxicity toward PC3 and HeLa cells. The GA‐NP also induced a higher level of apoptosis and mitochondrial depolarization in PC3 cells than free GA. The Met‐PEA‐PEG NP improved the therapeutic effect of GA and may serve as a potential carrier for anticancer drug delivery.
Developing a new family of hydrogel-based wound dressings that could have a dual biofunctionality of antibacterial and biological responses is highly desirable. In this study, an inherently effective ...antibacterial and biodegradable hydrogel dressing without the need for impregnated antibiotics was designed, synthesized, characterized, and examined for its effect on macrophages, which initiated inflammatory activity and activated both NO and TNF-α production for the purpose of achieving a better and faster wound healing. The purposes of this research was to develop a novel family of cationic biodegradable hydrogels based on arginine-based poly(ester urea urethane) (Arg-PEUU) and glycidyl methacrylate-modified chitosan (CS-GMA) that has both inherent antibacterial and bioactive functionality as a wound healing dressing for accelerated healing of contaminated or infected wounds. These hybrid hydrogels present a well-defined three-dimensional microporous network structure and have a high water absorption ability, and their biodegradation is effectively accelerated in the presence of lysozymes. The hemolytic activity test, MTT assay, and live/dead assay of these hybrid hydrogels indicated that they had no cytotoxicity toward red blood cells, NIH-3T3 fibroblast cells, and human vascular endothelial cells, thus corroborating their cytocompatibility. Furthermore, these hybrid hydrogels could elevate the release of both produced NO and TNF-α by stimulating and activating RAW 264.7 macrophages, augmenting their antibacterial biological response. The antibacterial assay of these hybrid hydrogels demonstrated their excellent antibacterial activity without the need for impregnated antibacterial agents. Taken together, this new family of biodegradable, antibacterial, and biologically responsive hybrid hydrogels exhibits great potential as biofunctional antibacterial wound dressing candidates for wound healing.
Abnormal tumour vasculature has a significant impact on tumour progression and response to therapy. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis and, thus, can be ...delivered to normalize tumour vasculature. However, a NO-delivery system with a prolonged half-life and a sustained release mechanism is currently lacking. Here we report the development of NanoNO, a nanoscale carrier that enables sustained NO release to efficiently deliver NO into hepatocellular carcinoma. Low-dose NanoNO normalizes tumour vessels and improves the delivery and effectiveness of chemotherapeutics and tumour necrosis factor-related, apoptosis-inducing, ligand-based therapy in both primary tumours and metastases. Furthermore, low-dose NanoNO reprogrammes the immunosuppressive tumour microenvironment toward an immunostimulatory phenotype, thereby improving the efficacy of cancer vaccine immunotherapy. Our findings demonstrate the ability of nanoscale NO delivery to efficiently reprogramme tumour vasculature and immune microenvironments to overcome resistance to cancer therapy, resulting in a therapeutic benefit.
A family of biodegradable, biocompatible, water soluble cationic polymer precursor, arginine‐based unsaturated poly (ester amide) (Arg‐UPEA), is reported. Its incorporation into conventional Pluronic ...diacrylate (Pluronic‐DA) to form hybrid hydrogels for a significant improvement of the biological performance of current synthetic hydrogels is shown. The gel fraction (Gf), equilibrium swelling ratio (Qeq), compressive modulus, and interior morphology of the hybrid hydrogels as well as their interactions with human fibroblasts and bovine endothelial cells are fully investigated. It is found that the incorporation of Arg‐UPEA into Pluronic‐DA hydrogels significantly changes their Qeq, mechanical strength, and interior morphology. The structure–property relationship of the newly fabricated hybrid hydrogels is studied in terms of the chemical structure of the Arg‐UPEA precursor, i.e., the number of methylene groups in the Arg‐UPEA repeating unit. The results indicate that increasing methylene groups in the Arg‐UPEA repeating unit increases Qeq and decreases the compressive modulus of hydrogels. When compared with a pure Pluronic hydrogel, the cationic Arg‐UPEAs/Pluronic hybrid hydrogels greatly improve the attachment and proliferation of human fibroblasts on hydrogel surfaces. A bovine aortic endothelial cells (BAEC) viability test in the interior of the hydrogels shows that the positively charged hybrid hydrogels can significantly improve the viability of the encapsulated endothelial cell over a 2 week study period when compared with a pure Pluronic hydrogel.
Unsaturated arginine poly(ester amide)s are prepared to improve the biocompatibility of Pluronic hydrogels. This is confirmed using fibroblast cell attachment and endothelial cell encapsulation tests.
Amyloid-β (Aβ) oligomers largely initiate the cascade underlying the pathology of Alzheimer's disease (AD). Galectin-3 (Gal-3), which is a member of the galectin protein family, promotes inflammatory ...responses and enhances the homotypic aggregation of cancer cells. Here, we examined the role and action mechanism of Gal-3 in Aβ oligomerization and Aβ toxicities. Wild-type (WT) and Gal-3-knockout (KO) mice, APP/PS1;WT mice, APP/PS1;Gal-3
mice and brain tissues from normal subjects and AD patients were used. We found that Aβ oligomerization is reduced in Gal-3 KO mice injected with Aβ, whereas overexpression of Gal-3 enhances Aβ oligomerization in the hippocampi of Aβ-injected mice. Gal-3 expression shows an age-dependent increase that parallels endogenous Aβ oligomerization in APP/PS1 mice. Moreover, Aβ oligomerization, Iba1 expression, GFAP expression and amyloid plaque accumulation are reduced in APP/PS1;Gal-3
mice compared with APP/PS1;WT mice. APP/PS1;Gal-3
mice also show better acquisition and retention performance compared to APP/PS1;WT mice. In studying the mechanism underlying Gal-3-promoted Aβ oligomerization, we found that Gal-3 primarily co-localizes with Iba1, and that microglia-secreted Gal-3 directly interacts with Aβ. Gal-3 also interacts with triggering receptor expressed on myeloid cells-2, which then mediates the ability of Gal-3 to activate microglia for further Gal-3 expression. Immunohistochemical analyses show that the distribution of Gal-3 overlaps with that of endogenous Aβ in APP/PS1 mice and partially overlaps with that of amyloid plaque. Moreover, the expression of the Aβ-degrading enzyme, neprilysin, is increased in Gal-3 KO mice and this is associated with enhanced integrin-mediated signaling. Consistently, Gal-3 expression is also increased in the frontal lobe of AD patients, in parallel with Aβ oligomerization. Because Gal-3 expression is dramatically increased as early as 3 months of age in APP/PS1 mice and anti-Aβ oligomerization is believed to protect against Aβ toxicity, Gal-3 could be considered a novel therapeutic target in efforts to combat AD.
Acute kidney injury (AKI) is a common complication of acute myocardial infarction (AMI), and is associated with adverse outcomes. The study aimed to identify a miRNA signature for the early diagnosis ...of post-AMI AKI.
A total of 108 patients admitted to a coronary care unit (CCU) were divided into four subgroups: AMI
AKI
, AMI
AKI
, AMI
AKI
, and AMI
AKI
. Thirty-six miRNA candidates were selected based on an extensive literature review. Real-time quantitative RT-PCR analysis was used to determine the expression levels of these miRNAs in the serum collected on the day of CCU admittance. TargetScan 7.1 and miRDB databases were used for target prediction and Metacore 6.13 was used for pathway analysis.
Through a stepwise selection based on abundance, hemolytic effect and differential expression between four groups, 9 miRNAs were found to have significantly differential expression levels as potential biomarkers for post-AMI AKI specifically. Noticeably, the expression levels of miR-24, miR-23a and miR-145 were significantly down-regulated in AMI
AKI
patients compared to those in AMI
AKI
patients. Combination of the three miRNAs as a panel showed the best performance in the early detection of AKI following AMI (AUC = 0.853, sensitivity 95.65%), compared to the analysis of serum neutrophil gelatinase-associated lipocalin (AUC = 0.735, sensitivity 63.16%). Furthermore, bioinformatic analysis indicated that these three miRNAs regulate the transforming growth factor beta signaling pathway and involve in apoptosis and fibrosis in AKI.
For the first time, this study identify a unique circulating miRNA signature (miR-24-3p, miR-23a-3p, miR-145-5p) that can potentially early detect AKI following AMI and may be involved in renal injury and fibrosis in post-AMI AKI pathogenesis.
Conductive fullerene electron‐transporting layers (ETLs) are developed to facilitate the solution processing of highly efficient inverted OSCs with power conversion efficiency (PCE) reaching 9.6%. ...Its high conductivity also allows devices to be fabricated independently of the ETL thickness (up to ca. 50 nm). Transient photovoltage (TPV) measurements are used to shed light on how these conductive ETLs help suppress charge recombination in solar cells.
Multiple phosphorylation sites of Drp1 have been characterized for their functional importance. However, the functional consequence of GSK3beta-mediated phosphorylation of Drp1 remains unclear. In ...this report, we pinpointed 11 Serine/Threonine sites spanning from residue 634~736 of the GED domain and robustly confirmed Drp1 Ser693 as a novel GSK3beta phosphorylation site. Our results suggest that GSK3beta-mediated phosphorylation at Ser693 does cause a dramatic decrease of GTPase activity; in contrast, GSK3beta-mediated phosphorylation at Ser693 appears not to affect Drp1 inter-/intra-molecular interactions. After identifying Ser693 as a GSK3beta phosphorylation site, we also determined that K679 is crucial for GSK3beta-binding, which strongly suggests that Drp1 is a novel substrate for GSK3beta. Thereafter, we found that overexpressed S693D, but not S693A mutant, caused an elongated mitochondrial morphology which is similar to that of K38A, S637D and K679A mutants. Interestedly, using H89 and LiCl to inhibit PKA and GSK3beta signaling, respectively, it appears that a portion of the elongated mitochondria switched to a fragmented phenotype. In investigating the biofunctionality of phosphorylation sites within the GED domain, cells overexpressing Drp1 S693D and S637D, but not S693A, showed an acquired resistance to H(2)O(2)-induced mitochondrial fragmentation and ensuing apoptosis, which affected cytochrome c, capase-3, -7, and PARP, but not LC3B, Atg-5, Beclin-1 and Bcl2 expressions. These results also showed that the S693D group is more effective in protecting both non-neuronal and neuronal cells from apoptotic death than the S637D group. Altogether, our data suggest that GSK3beta-mediated phosphorylation at Ser693 of Drp1 may be associated with mitochondrial elongation via down-regulating apoptosis, but not autophagy upon H(2)O(2) insult.
In first-line treatment of Helicobacter pylori, we have previously shown that the eradication frequency was 83·7% (95% CI 80·4–86·6) for triple therapy for 14 days (T14; lansoprazole 30 mg, ...amoxicillin 1 g, and clarithromycin 500 mg, all given twice daily), 85·9% (82·7–88·6) for concomitant therapy for 10 days (C10; lansoprazole 30 mg, amoxicillin 1 g, clarithromycin 500 mg, and metronidazole 500 mg, all given twice daily), and 90·4% (87·6–92·6) for bismuth quadruple therapy for 10 days (BQ10; bismuth tripotassium dicitrate 300 mg four times a day, lansoprazole 30 mg twice daily, tetracycline 500 mg four times a day, and metronidazole 500 mg three times a day). In this follow-up study, we assess short-term and long-term effects of these therapies on the gut microbiota, antibiotic resistance, and metabolic parameters.
This was a multicentre, open-label, randomised trial done at nine medical centres in Taiwan. Adult patients (>20 years) with documented H pylori infection were randomly assigned (1:1:1, with block sizes of six) to receive T14, C10, or BQ10. We assessed long-term outcomes (reinfection frequency, changes in the gut microbiota, antibiotic resistance, and metabolic parameters) in patients with available data, excluding all protocol violators and those with unknown post-treatment H pylori status. Faecal samples were collected before treatment and 2 weeks, 2 months, and at least 1 year after eradication therapy. Amplification of the V3 and V4 hypervariable regions of the 16S rRNA was done followed by high-throughput sequencing. Susceptibility testing for faecal Escherichia coli and Klebsiella pneumoniae was done. This trial is complete and registered with ClinicalTrials.gov, NCT01906879.
Between July 17, 2013, and April 20, 2016, 1620 participants were randomly assigned to the three treatment groups (540 33% per group). 1214 (75%) attended 1-year follow-up and are included in this analysis. Compared with baseline, alpha diversity was significantly reduced 2 weeks after T14 (p=0·0002), C10 (p<0·0001), and BQ10 (p<0·0001) treatment. Beta diversity was also significantly altered 2 weeks after T14 (p=0·0010), C10 (p=0·0001), and BQ10 (p=0·0001). Alpha diversity and beta diversity were restored at week 8 (p=0·14 and p=0·918, respectively) and 1 year (p=0·14 and p=0·918) after T14, but were not fully recovered at week 8 and after 1 year in patients treated with C10 (p=0·0001 and p=0·013 at week 8; p=0·019 and p=0·064 at 1 year) and BQ10 (p<0·0001 and p=0·0002; p=0·001 and p=0·029). A transient increase at week 2 after T14 and C10 of the resistance rates of E coli to ampicillin-sulbactam (12% 15/127 to 66% 38/58 for T14, 7% 10/135 to 64% 28/44 for C10), cefazolin (13% 16/127 to 43% 25/58 for T14, 10% 13/135 to 41% 18/44 for C10), cefmetazole (8% 10/127 to 26% 15/58 for T14, 4% 5/135 to 18% 8/44 for C10), levofloxacin (8% 10/127 to 35% 20/58 for T14, 7% 10/135 to 32% 14/44 for C10), gentamicin (13% 19/146 to 47% 27/58 for T14, 15% 22/149 to 45% 20/44 for C10), and trimethoprim–sulfamethoxazole (33% 48/146 to 86% 50/58 for T14, 28% 42/148 to 86% 38/44 for C10; p<0·05 in paired samples in the above analyses) returned to basal state at week 8 and after 1 year. Although bodyweight and body-mass index slightly increased, there were significant improvements in metabolic parameters, with a decrease in insulin resistance, triglycerides, and LDL and an increase in HDL. Overall, there was no significant change in the prevalence of metabolic syndrome at week 8 and 1 year after T14, C10, and BQ10.
Eradication of H pylori infection has minimal disruption of the microbiota, no effect on antibiotic resistance of E coli, and some positive effects on metabolic parameters. Collectively, these results lend support to the long-term safety of H pylori eradication therapy.
National Taiwan University Hospital and Ministry of Science and Technology of Taiwan.
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