125 results on '"Niu, Mengmeng"'
Search Results
102. Effect of an external electric field on the electronic properties of SnS2/PbI2 van der Waals heterostructures.
- Author
-
Ma, Yaqiang, Zhao, Xu, Niu, Mengmeng, Dai, Xianqi, Li, Wei, Li, Yi, Zhao, Mingyu, Wang, Tianxing, and Tang, Yanan
- Published
- 2017
- Full Text
- View/download PDF
103. Monoclinic Ga2O3 (100) surface as a robust photocatalyst for water-splitting.
- Author
-
Ma, Yaqiang, Zhao, Xu, Niu, Mengmeng, Li, Wei, Wang, Xiaolong, Zhai, Caiyun, Wang, Tianxing, Tang, Yanan, and Dai, Xianqi
- Published
- 2017
- Full Text
- View/download PDF
104. Biodistribution and in Vivo Activities of Tumor-Associated Macrophage-Targeting Nanoparticles Incorporated with Doxorubicin
- Author
-
Niu, Mengmeng, primary, Naguib, Youssef W., additional, Aldayel, Abdulaziz M., additional, Shi, Yan-chun, additional, Hursting, Stephen D., additional, Hersh, Matthew A., additional, and Cui, Zhengrong, additional
- Published
- 2014
- Full Text
- View/download PDF
105. Preparation of vincristine sulfate-loaded poly (butylcyanoacrylate) nanoparticles modified with pluronic F127 and evaluation of their lymphatic tissue targeting
- Author
-
Tan, Rong, primary, Niu, Mengmeng, additional, Zhao, Jihui, additional, Liu, Ying, additional, and Feng, Nianping, additional
- Published
- 2014
- Full Text
- View/download PDF
106. Liposomes containing glycocholate as potential oral insulin delivery systems: preparation, in vitro characterization, and improved protection against enzymatic degradation
- Author
-
Niu,Mengmeng, Lu,Yi, Hovgaard,Lars, Wu,Wei, Niu,Mengmeng, Lu,Yi, Hovgaard,Lars, and Wu,Wei
- Abstract
Mengmeng Niu1, Yi Lu1, Lars Hovgaard2, Wei Wu11School of Pharmacy, Fudan University, Shanghai, People's Republic of China; 2Oral Formulation Development, Novo Nordisk A/S, Maalov, DenmarkBackground: Oral delivery of insulin is challenging and must overcome the barriers of gastric and enzymatic degradation as well as low permeation across the intestinal epithelium. The present study aimed to develop a liposomal delivery system containing glycocholate as an enzyme inhibitor and permeation enhancer for oral insulin delivery.Methods: Liposomes containing sodium glycocholate were prepared by a reversed-phase evaporation method followed by homogenization. The particle size and entrapment efficiency of recombinant human insulin (rhINS)-loaded sodium glycocholate liposomes can be easily adjusted by tuning the homogenization parameters, phospholipid:sodium glycocholate ratio, insulin:phospholipid ratio, water:ether volume ratio, interior water phase pH, and the hydration buffer pH.Results: The optimal formulation showed an insulin entrapment efficiency of 30% ± 2% and a particle size of 154 ± 18 nm. A conformational study by circular dichroism spectroscopy and a bioactivity study confirmed the preserved integrity of rhINS against preparative stress. Transmission electron micrographs revealed a nearly spherical and deformed structure with discernable lamella for sodium glycocholate liposomes. Sodium glycocholate liposomes showed better protection of insulin against enzymatic degradation by pepsin, trypsin, and a-chymotrypsin than liposomes containing the bile salt counterparts of sodium taurocholate and sodium deoxycholate.Conclusion: Sodium glycocholate liposomes showed promising in vitro characteristics and have the potential to be able to deliver insulin orally.Keywords: liposomes, glycocholate, insulin, enzymatic degradation, oral
- Published
- 2011
107. Enhanced oral bioavailability of cyclosporine A by liposomes containing a bile salt
- Author
-
Guan,Peipei, Lu,Yi, Qi,Jianping, Niu,Mengmeng, Lian,Ruyue, Hu,Fuqiang, Wu,Wei, Guan,Peipei, Lu,Yi, Qi,Jianping, Niu,Mengmeng, Lian,Ruyue, Hu,Fuqiang, and Wu,Wei
- Abstract
Peipei Guan1, Yi Lu1, Jianping Qi1, Mengmeng Niu1, Ruyue Lian1, Fuqiang Hu2, Wei Wu11School of Pharmacy, Fudan University, Shanghai, People's Republic of China; 2School of Pharmacy, Zhejiang University, Hangzhou, People's Republic of ChinaAbstract: The main purpose of this study was to evaluate liposomes containing a bile salt, sodium deoxycholate (SDC), as oral drug delivery systems to enhance the oral bioavailability of the poorly water-soluble and poorly permeable drug, cyclosporine A (CyA). Liposomes composed of soybean phosphatidylcholine (SPC) and SDC were prepared by a thin-film dispersion method followed by homogenization. Several properties of the liposomes including particle size, polydispersity index, and entrapment efficiency were characterized. The in vitro release of CyA from these liposomes was less than 5% at 12 hours as measured by a dynamic dialysis method. The pharmacokinetic results in rats showed improved absorption of CyA in SPC/SDC liposomes, compared with CyA-loaded conventional SPC/cholesterol (Chol) liposomes and microemulsion-based Sandimmune Neoral®. The relative oral bioavailability of CyA-loaded SPC/SDC and SPC/Chol liposomes was 120.3% and 98.6%, respectively, with Sandimmun Neoral as the reference. The enhanced bioavailability of CyA was probably due to facilitated absorption by the liposomes containing SDC rather than improved release rate.Keywords: liposomes, bile salt, sodium deoxycholate, cyclosporine A, oral bioavailability
- Published
- 2011
108. A monitoring method based on stacked AutoEncoder considering sensor fault.
- Author
-
Wang, Honghui, Liu, Kuo, Qin, Bo, Niu, Mengmeng, Qiao, Shi, and Wang, Yongqing
- Published
- 2022
- Full Text
- View/download PDF
109. Targeting of Tumor-Associated Macrophages Made Possible by PEG-Sheddable, Mannose-Modified Nanoparticles
- Author
-
Zhu, Saijie, primary, Niu, Mengmeng, additional, O’Mary, Hannah, additional, and Cui, Zhengrong, additional
- Published
- 2013
- Full Text
- View/download PDF
110. Liposomes containing glycocholate as potential oral insulin delivery systems: preparation, in vitro characterization, and improved protection against enzymatic degradation
- Author
-
Wu, Wei, primary, Niu, Mengmeng, additional, Lu, Yi, additional, and Hovgaard, Lars, additional
- Published
- 2011
- Full Text
- View/download PDF
111. The Effect of Chitosan Molecular Weight on the Characteristics of Spray-Dried Methotrexate-Loaded Chitosan Microspheres for Nasal Administration
- Author
-
Sun, Yu, primary, Cui, Fude, additional, Shi, Kai, additional, Wang, Jiamiao, additional, Niu, Mengmeng, additional, and Ma, Ruijing, additional
- Published
- 2009
- Full Text
- View/download PDF
112. Biodistribution and in VivoActivities of Tumor-Associated Macrophage-Targeting Nanoparticles Incorporated with Doxorubicin
- Author
-
Niu, Mengmeng, Naguib, Youssef W., Aldayel, Abdulaziz M., Shi, Yan-chun, Hursting, Stephen D., Hersh, Matthew A., and Cui, Zhengrong
- Abstract
Tumor-associated macrophages (TAMs) are increasingly considered a viable target for tumor imaging and therapy. Previously, we reported that innovative surface-functionalization of nanoparticles may help target them to TAMs. In this report, using poly(lactic-co-glycolic) acid (PLGA) nanoparticles incorporated with doxorubicin (DOX) (DOX-NPs), we studied the effect of surface-modification of the nanoparticles with mannose and/or acid-sensitive sheddable polyethylene glycol (PEG) on the biodistribution of DOX and the uptake of DOX by TAMs in tumor-bearing mice. We demonstrated that surface-modification of the DOX-NPs with both mannose and acid-sensitive sheddable PEG significantly increased the accumulation of DOX in tumors, enhanced the uptake of the DOX by TAMs, but decreased the distribution of DOX in mononuclear phagocyte system (MPS), such as liver. We also confirmed that the acid-sensitive sheddable PEGylated, mannose-modified DOX-nanoparticles (DOX-AS-M-NPs) targeted TAMs because depletion of TAMs in tumor-bearing mice significantly decreased the accumulation of DOX in tumor tissues. Furthermore, in a B16-F10 tumor-bearing mouse model, we showed that the DOX-AS-M-NPs were significantly more effective than free DOX in controlling tumor growth but had only minimum effect on the macrophage population in mouse liver and spleen. The AS-M-NPs are promising in targeting cytotoxic or macrophage-modulating agents into tumors to improve tumor therapy.
- Published
- 2014
- Full Text
- View/download PDF
113. Evaluation of biochemical and antioxidant dynamics during the co‐fermentation of dehusked barley with Rhizopus oryzae and Lactobacillus plantarum.
- Author
-
Wang, Kun, Niu, Mengmeng, Song, Dawei, Liu, Yang, Wu, Yue, Zhao, Jing, Li, Shize, and Lu, Baoxin
- Subjects
- *
RHIZOPUS oryzae , *LACTOBACILLUS plantarum , *BARLEY , *LACTIC acid bacteria , *ANIMAL feeds , *NUTRITIONAL value , *PYRICULARIA oryzae - Abstract
Barley is an ancient and important functional crop. In this study, the biochemical and antioxidant dynamics of dehusked barley during co‐fermentation with Lactobacillus plantarum and Rhizopus oryzae were investigated. Results showed that amino acid nitrogen, soluble protein, <10 kDa peptide, and free phenolic contents increased with fermentation time; whereas the lactic acid bacteria count, reducing sugar, and free flavonoid contents showed a tendency to increase first and then decrease. SDS‐PAGE analysis indicated that bands at >25 and <18.4 kDa were shown with improved intensity with time, whereas bands at 18.4–25 kDa were disappeared. Additionally, fermentation time led to an increase in DPPH, hydroxyl, ABTS+ radical scavenging activity, and ferric reducing antioxidant power. Thus, this study demonstrated that co‐fermentation with L. plantarum and R. oryzae could improve nutrition and potential bioactivity of barley, and use barley as a good solid‐state food carrier for probiotics. Practical applications: Barley is rich in nutrition and has a huge production. However, due to its high‐fiber and special protein composition, there is a certain palatability problem whether it is used to produce flour or other products. Therefore, most of the barley is destined to animal feed and malt, and only a small part is used directly for human consumption. Aiming at this problem, on the basis of the optimization of the fermentation process at early stage, our results further demonstrated co‐fermentation with L. plantarum and R. oryzae could enhance the nutritional value and potential bioactivity of barley, thus providing a novel approach to develop functional barley food and improve the direct utilization rate of barley in food processing. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
114. Biodistribution and in Vivo Activities of Tumor-Associated Macrophage-Targeting Nanoparticles Incorporated with Doxorubicin
- Author
-
Niu, Mengmeng, Aldayel, Abdulaziz M., Naguib, Youssef W., Hersh, Matthew A., Cui, Zhengrong, Shi, Yan-chun, and Hursting, Stephen D.
- Subjects
carbohydrates (lipids) ,organic chemicals ,polycyclic compounds ,technology, industry, and agriculture ,macromolecular substances ,3. Good health - Abstract
Tumor-associated macrophages (TAMs) are increasingly considered a viable target for tumor imaging and therapy. Previously, we reported that innovative surface-functionalization of nanoparticles may help target them to TAMs. In this report, using poly(lactic-co-glycolic) acid (PLGA) nanoparticles incorporated with doxorubicin (DOX) (DOX-NPs), we studied the effect of surface-modification of the nanoparticles with mannose and/or acid-sensitive sheddable polyethylene glycol (PEG) on the biodistribution of DOX and the uptake of DOX by TAMs in tumor-bearing mice. We demonstrated that surface-modification of the DOX-NPs with both mannose and acid-sensitive sheddable PEG significantly increased the accumulation of DOX in tumors, enhanced the uptake of the DOX by TAMs, but decreased the distribution of DOX in mononuclear phagocyte system (MPS), such as liver. We also confirmed that the acid-sensitive sheddable PEGylated, mannose-modified DOX-nanoparticles (DOX-AS-M-NPs) targeted TAMs because depletion of TAMs in tumor-bearing mice significantly decreased the accumulation of DOX in tumor tissues. Furthermore, in a B16-F10 tumor-bearing mouse model, we showed that the DOX-AS-M-NPs were significantly more effective than free DOX in controlling tumor growth but had only minimum effect on the macrophage population in mouse liver and spleen. The AS-M-NPs are promising in targeting cytotoxic or macrophage-modulating agents into tumors to improve tumor therapy.
115. Impact of polystyrene nanoplastics on apoptosis and inflammation in zebrafish larvae: Insights from reactive oxygen species perspective.
- Author
-
Pei J, Chen S, Li L, Wang K, Pang A, Niu M, Peng X, Li N, Wu H, and Nie P
- Subjects
- Animals, Oxidative Stress drug effects, Nanoparticles toxicity, Zebrafish, Reactive Oxygen Species metabolism, Apoptosis drug effects, Polystyrenes toxicity, Inflammation chemically induced, Larva drug effects, Water Pollutants, Chemical toxicity
- Abstract
In recent years, there has been a growing focus on the toxicity and mortality induced by nanoplastics (NPs) in aquatic organisms. However, studies investigating mechanisms underlying oxidative stress (OS), apoptosis, and inflammation induced by NPs in fish remain limited. This study observed that polystyrene NPs (PS-NPs) were accumulated into zebrafish larvae and zebrafish embryonic fibroblast (ZF4 cells), accompanied by the occurrence of pathological damage both at the cellular and tissue-organ level. Additionally, the transcriptional up-regulation of NADPH oxidases (NOXs) and subsequent excessive generation of reactive oxygen species (ROS) resulted in notable changes in the relative mRNA and protein expression levels associated with antioxidant oxidase systems in larvae. Furthermore, the study identified the impact of NPs on mitochondrial ultrastructural, resulting in mitochondrial depolarization and downregulation of mRNA expression related to the electron transport chain due to excessive ROS generation. Short-term exposure to NPs also triggered apoptosis and inflammation in zebrafish larvae, evident from significant up-regulation in mRNA expressions of proapoptotic factors and NF-κB proinflammatory signaling pathway, as well as increased transcription and protein levels of pro-inflammatory factors in larvae. Inhibition of intracellular excessive ROS effectively reduced the induction of apoptosis, NF-κB P65 nuclear migration levels, and cytokine secretion, underscoring OS as a pivotal factor throughout the process of apoptosis and inflammatory responses induced by NPs. This research significantly advances our comprehension of biological effects and underlying mechanisms of NPs in freshwater fish., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
116. Exploring the characteristic "plug-in" configuration of an adsorbed starburst molecule.
- Author
-
Hao X, Li Y, Zhang T, Niu M, Yang H, Qiao J, Grazioli C, Guarnaccio A, Liu L, Zhang Q, Puglia C, and Wang Y
- Abstract
In this study, the adsorption of starburst molecules (C
57 H48 N4 , SBM) deposited on Au(111) was investigated by scanning tunneling microscopy (STM). SBM molecules selectively adsorb on the face-centered-cubic regions of Au(111) in quasi one-dimensional chains. Compared with the SBM structure on hBN/Rh(111), the assembly structure of SBM on Au(111) can be clearly confirmed to be molecular chains in the "plug-in" configuration. Scanning tunneling spectroscopy (STS) revealed that the interaction between SBM molecules and Au(111) induces the modification of the molecular electronic states. The STS mapping further revealed a continuous 1D electronic state concentrated at the center of the SBM molecular chains.- Published
- 2024
- Full Text
- View/download PDF
117. Evaluation of in vitro Skin Permeation of Clascoterone From Clascoterone Topical Cream, 1% (w/w).
- Author
-
Yang Y, Wang J, Wanasathop A, Niu M, Ghosh P, Zidan A, Gu J, Hunt R, Faustino P, Ashraf M, and Xu X
- Subjects
- Skin metabolism, Administration, Cutaneous, Chromatography, Liquid methods, Animals, Permeability, Swine, Humans, Propionates, Skin Absorption drug effects, Skin Absorption physiology, Skin Cream pharmacokinetics, Skin Cream administration & dosage, Cortodoxone administration & dosage, Cortodoxone pharmacokinetics, Cortodoxone metabolism, Cortodoxone analogs & derivatives, Tandem Mass Spectrometry methods
- Abstract
Winlevi
® (clascoterone) topical cream (1%, w/w) was approved by the U.S. FDA for the treatment of acne vulgaris in patients 12 years of age and older. The active ingredient, clascoterone, is not stable in physiological solutions and can hydrolyze to cortexolone at body temperature. Instability of clascoterone poses a significant challenge in accurately assessing the rate and extent of clascoterone permeation in vitro. Therefore, the purpose of this study was to develop an in vitro skin permeation test (IVPT) method, and a robust analytical method, that can minimize hydrolyzation of clascoterone during the study for quantification of clascoterone. Two IVPT methods, using either vertical diffusion cells or flow-through cells, were developed and compared to evaluate in vitro permeation of clascoterone from Winlevi. A liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was developed to monitor the level of clascoterone and cortexolone in the IVPT samples. The analytical method features a 2-min high-throughput analysis with good linearity, selectivity, and showed a lower limit of quantitation (LLOQ) of 0.5 ng/mL for both clascoterone and cortexolone. The in vitro skin permeation of clascoterone and cortexolone was observed as early as 2 h in both IVPT methods. A substantive amount of clascoterone was found to hydrolyze to cortexolone when using the vertical static diffusion cells with aliquot sampling. Conversely, degradation of clascoterone was significantly minimized when using the flow-through diffusion cells with fractional sampling. The data enhanced our understanding of in vitro permeation of clascoterone following topical application of the Winlevi topical cream, 1% and underscores the importance of IVPT method development and optimization during product development., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)- Published
- 2024
- Full Text
- View/download PDF
118. Hypoxia-activated XBP1s recruits HDAC2-EZH2 to engage epigenetic suppression of ΔNp63α expression and promote breast cancer metastasis independent of HIF1α.
- Author
-
Chen H, Yu S, Ma R, Deng L, Yi Y, Niu M, Xu C, and Xiao ZJ
- Subjects
- Humans, Female, Animals, Cell Line, Tumor, Neoplasm Metastasis, Mice, Gene Expression Regulation, Neoplastic, Transcription Factors metabolism, Transcription Factors genetics, Cell Hypoxia genetics, Breast Neoplasms pathology, Breast Neoplasms genetics, Breast Neoplasms metabolism, Enhancer of Zeste Homolog 2 Protein metabolism, Enhancer of Zeste Homolog 2 Protein genetics, X-Box Binding Protein 1 metabolism, X-Box Binding Protein 1 genetics, Histone Deacetylase 2 metabolism, Histone Deacetylase 2 genetics, Hypoxia-Inducible Factor 1, alpha Subunit metabolism, Hypoxia-Inducible Factor 1, alpha Subunit genetics, Epigenesis, Genetic, Tumor Suppressor Proteins metabolism, Tumor Suppressor Proteins genetics
- Abstract
Hypoxia is a hallmark of cancer development. However, the molecular mechanisms by which hypoxia promotes tumor metastasis are not fully understood. In this study, we demonstrate that hypoxia promotes breast cancer metastasis through suppression of ΔNp63α in a HIF1α-independent manner. We show that hypoxia-activated XBP1s forms a stable repressor protein complex with HDAC2 and EZH2 to suppress ΔNp63α transcription. Notably, H3K27ac is predominantly occupied on the ΔNp63 promoter under normoxia, while H3K27me3 on the promoter under hypoxia. We show that XBP1s binds to the ΔNp63 promoter to recruit HDAC2 and EZH2 in facilitating the switch of H3K27ac to H3K27me3. Pharmacological inhibition or the knockdown of either HDAC2 or EZH2 leads to increased H3K27ac, accompanied by the reduced H3K27me3 and restoration of ΔNp63α expression suppressed by hypoxia, resulting in inhibition of cell migration. Furthermore, the pharmacological inhibition of IRE1α, but not HIF1α, upregulates ΔNp63α expression in vitro and inhibits tumor metastasis in vivo. Clinical analyses reveal that reduced p63 expression is correlated with the elevated expression of XBP1, HDAC2, or EZH2, and is associated with poor overall survival in human breast cancer patients. Together, these results indicate that hypoxia-activated XBP1s modulates the epigenetic program in suppression of ΔNp63α to promote breast cancer metastasis independent of HIF1α and provides a molecular basis for targeting the XBP1s/HDAC2/EZH2-ΔNp63α axis as a putative strategy in the treatment of breast cancer metastasis., (© 2024. The Author(s), under exclusive licence to ADMC Associazione Differenziamento e Morte Cellulare.)
- Published
- 2024
- Full Text
- View/download PDF
119. Understanding the impact of formulation design on microstructure and drug release from porous microparticle-based tretinoin topical gels.
- Author
-
Elfakhri KH, Niu M, Ghosh P, Ramezanli T, Raney SG, Kamal N, Ashraf M, and Zidan AS
- Subjects
- Drug Liberation, Porosity, Gels chemistry, Viscosity, Tretinoin
- Abstract
For proportionally formulated intermediate strengths of a topical product, the relationship of drug release across multiple strengths of a given product is not always well understood. The current study aims to assess the proportionality of tretinoin release rates across multiple strengths of tretinoin topical gels when manufactured using two different methods to understand the impact of formulation design on drug product microstructure and tretinoin release rate. Two groups of tretinoin gels of 0.04 %, 0.06 %, 0.08 % and 0.1 % strengths were manufactured. Gels in Group I were prepared by incorporating 4-10 % g/g of 1 % w/w tretinoin-loaded microparticles into a gel base. Gels in Group II were manufactured using 10 % g/g of the microparticles that were loaded with increasing amounts (0.4-1 % w/w) of tretinoin. The two groups of gels were characterized by evaluating microstructure using a polarized microscope, rheology using an oscillatory rheometer, and drug release using Vison® Microette™ Hanson vertical diffusion cells. The microscopic images were used to discriminate between the two groups of gels based on the abundance of microparticles in the gel matrix observed in the images. This abundance increased across gels of Group I and was similar across gels of Group II. The rheology parameters, namely viscosity at a shear rate of 10 s
-1 , shear thinning rate, storage, and loss modulus, increased across gels of Group I, and were not significantly different across gels of Group II. The release rate of tretinoin from the drug products was proportional to the nominal strength of the drug product in both Group I and Group II, with a correlation coefficient of 0.95 in each case, although the absolute release rates differed. Overall, changing the formulation design of tretinoin topical gels containing porous microparticles may change the physicochemical and structural properties, as well as the drug release rate of the product. Further, keeping the formulation design consistent across all strengths of microparticle-based topical gels is important to achieve proportional release rates across multiple strengths of a given drug product., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)- Published
- 2024
- Full Text
- View/download PDF
120. USP36 stabilizes nucleolar Snail1 to promote ribosome biogenesis and cancer cell survival upon ribotoxic stress.
- Author
-
Qin K, Yu S, Liu Y, Guo R, Guo S, Fei J, Wang Y, Jia K, Xu Z, Chen H, Li F, Niu M, Dai MS, Dai L, Cao Y, Zhang Y, Xiao ZJ, and Yi Y
- Subjects
- Humans, Cell Survival, Ribosomes, Cell Nucleolus, Ubiquitin Thiolesterase, Neoplasms, Leukemia
- Abstract
Tumor growth requires elevated ribosome biogenesis. Targeting ribosomes is an important strategy for cancer therapy. The ribosome inhibitor, homoharringtonine (HHT), is used for the clinical treatment of leukemia, yet it is ineffective for the treatment of solid tumors, the reasons for which remain unclear. Here we show that Snail1, a key factor in the regulation of epithelial-to-mesenchymal transition, plays a pivotal role in cellular surveillance response upon ribotoxic stress. Mechanistically, ribotoxic stress activates the JNK-USP36 signaling to stabilize Snail1 in the nucleolus, which facilitates ribosome biogenesis and tumor cell survival. Furthermore, we show that HHT activates the JNK-USP36-Snail1 axis in solid tumor cells, but not in leukemia cells, resulting in solid tumor cell resistance to HHT. Importantly, a combination of HHT with the inhibition of the JNK-USP36-Snail1 axis synergistically inhibits solid tumor growth. Together, this study provides a rationale for targeting the JNK-USP36-Snail1 axis in ribosome inhibition-based solid tumor therapy., (© 2023. Springer Nature Limited.)
- Published
- 2023
- Full Text
- View/download PDF
121. Alkyne Insertion Enabled Vinyl to Acyl 1,5-Palladium Migration: Rapid Access to Substituted 5-Membered-Dihydrobenzofurans and Indolines.
- Author
-
Ding M, Ou P, Li X, Yu Y, Niu M, Yang Y, Huang Y, Wang ZX, and Huang X
- Abstract
"Through space" palladium/hydrogen shift is an efficient strategy to achieve selective functionalization of a specific remote C-H bond. Compared with relatively extensive exploited 1,4-palladium migration process, the relevant 1,5-Pd/H shift was far less investigated. We herein report a novel 1,5-Pd/H shift pattern between a vinyl and an acyl group. Through the pattern, rapid access to 5-membered-dihydrobenzofuran and indoline derivatives has been achieved. Further studies have unveiled an unprecedented trifunctionalization (vinylation, alkynylation and amination) of a phenyl ring through 1,5-palladium migration relayed decarbonylative Catellani type reaction. A series of mechanistic investigations and DFT calculations have provided insights into the reaction pathway. Notably, it was unveiled that the 1,5-palladium migration in our case prefers a stepwise mechanism involving a Pd
IV intermediate., (© 2023 Wiley-VCH GmbH.)- Published
- 2023
- Full Text
- View/download PDF
122. Acid-Sensitive Sheddable PEGylated PLGA Nanoparticles Increase the Delivery of TNF-α siRNA in Chronic Inflammation Sites.
- Author
-
Aldayel AM, Naguib YW, O'Mary HL, Li X, Niu M, Ruwona TB, and Cui Z
- Abstract
There has been growing interest in utilizing small interfering RNA (siRNA) specific to pro-inflammatory cytokines, such as tumor necrosis factor-α ( TNF-α), in chronic inflammation therapy. However, delivery systems that can increase the distribution of the siRNA in chronic inflammation sites after intravenous administration are needed. Herein we report that innovative functionalization of the surface of siRNA-incorporated poly (lactic-co-glycolic) acid (PLGA) nanoparticles significantly increases the delivery of the siRNA in the chronic inflammation sites in a mouse model. The TNF-α siRNA incorporated PLGA nanoparticles were prepared by the standard double emulsion method, but using stearoyl-hydrazone-polyethylene glycol 2000, a unique acid-sensitive surface active agent, as the emulsifying agent, which renders (i) the nanoparticles PEGylated and (ii) the PEGylation sheddable in low pH environment such as that in chronic inflammation sites. In a mouse model of lipopolysaccharide-induced chronic inflammation, the acid-sensitive sheddable PEGylated PLGA nanoparticles showed significantly higher accumulation or distribution in chronic inflammation sites than PLGA nanoparticles prepared with an acid-insensitive emulsifying agent (i.e., stearoyl-amide-polyethylene glycol 2000) and significantly increased the distribution of the TNF-α siRNA incorporated into the nanoparticles in inflamed mouse foot.
- Published
- 2016
- Full Text
- View/download PDF
123. Delivery of vincristine sulfate-conjugated gold nanoparticles using liposomes: a light-responsive nanocarrier with enhanced antitumor efficiency.
- Author
-
Liu Y, He M, Niu M, Zhao Y, Zhu Y, Li Z, and Feng N
- Subjects
- Animals, Cell Survival drug effects, HeLa Cells, Humans, Mice, Mice, Nude, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacokinetics, Antineoplastic Agents pharmacology, Drug Carriers chemistry, Drug Carriers pharmacokinetics, Gold chemistry, Liposomes chemistry, Liposomes pharmacokinetics, Metal Nanoparticles chemistry, Vincristine chemistry, Vincristine pharmacokinetics, Vincristine pharmacology
- Abstract
Rapid drug release at the specific site of action is still a challenge for antitumor therapy. Development of stimuli-responsive hybrid nanocarriers provides a promising strategy to enhance therapeutic effects by combining the unique features of each component. The present study explored the use of drug-gold nanoparticle conjugates incorporated into liposomes to enhance antitumor efficiency. A model drug, vincristine sulfate, was physically conjugated with gold nanoparticles and verified by UV-visible and fourier transform infrared spectroscopy, and differential scanning calorimetry. The conjugates were incorporated into liposomes by film dispersion to yield nanoparticles (113.4 nm) with light-responsive release properties, as shown by in vitro release studies. Intracellular uptake and distribution was studied in HeLa cells using transmission electron microscopy and confocal laser scanning microscopy. This demonstrated liposome internalization and localization in endosomal-lysosomal vesicles. Fluorescence intensity increased in cells exposed to UV light, indicating that this stimulated intracellular drug release; this finding was confirmed by quantitative analyses using flow cytometry. Antitumor efficacy was evaluated in HeLa cells, both in culture and in implants in vivo in nude mice. HeLa cell viability assays showed that light exposure enhanced liposome cytotoxicity and induction of apoptosis. Furthermore, treatment with the prepared liposomes coupled with UV light exposure produced greater antitumor effects in nude mice and reduced side effects, as compared with free vincristine sulfate.
- Published
- 2015
- Full Text
- View/download PDF
124. Liposomes containing glycocholate as potential oral insulin delivery systems: preparation, in vitro characterization, and improved protection against enzymatic degradation.
- Author
-
Niu M, Lu Y, Hovgaard L, and Wu W
- Subjects
- Administration, Oral, Analysis of Variance, Animals, Circular Dichroism, Drug Stability, Glycocholic Acid administration & dosage, Humans, Hydrogen-Ion Concentration, Insulin, Regular, Human administration & dosage, Insulin, Regular, Human pharmacokinetics, Liposomes administration & dosage, Male, Mice, Microscopy, Electron, Transmission, Particle Size, Pressure, Endopeptidases metabolism, Glycocholic Acid chemistry, Insulin, Regular, Human chemistry, Liposomes chemistry
- Abstract
Background: Oral delivery of insulin is challenging and must overcome the barriers of gastric and enzymatic degradation as well as low permeation across the intestinal epithelium. The present study aimed to develop a liposomal delivery system containing glycocholate as an enzyme inhibitor and permeation enhancer for oral insulin delivery., Methods: Liposomes containing sodium glycocholate were prepared by a reversed-phase evaporation method followed by homogenization. The particle size and entrapment efficiency of recombinant human insulin (rhINS)-loaded sodium glycocholate liposomes can be easily adjusted by tuning the homogenization parameters, phospholipid:sodium glycocholate ratio, insulin:phospholipid ratio, water:ether volume ratio, interior water phase pH, and the hydration buffer pH., Results: The optimal formulation showed an insulin entrapment efficiency of 30% ± 2% and a particle size of 154 ± 18 nm. A conformational study by circular dichroism spectroscopy and a bioactivity study confirmed the preserved integrity of rhINS against preparative stress. Transmission electron micrographs revealed a nearly spherical and deformed structure with discernable lamella for sodium glycocholate liposomes. Sodium glycocholate liposomes showed better protection of insulin against enzymatic degradation by pepsin, trypsin, and α-chymotrypsin than liposomes containing the bile salt counterparts of sodium taurocholate and sodium deoxycholate., Conclusion: Sodium glycocholate liposomes showed promising in vitro characteristics and have the potential to be able to deliver insulin orally.
- Published
- 2011
- Full Text
- View/download PDF
125. Enhanced oral bioavailability of cyclosporine A by liposomes containing a bile salt.
- Author
-
Guan P, Lu Y, Qi J, Niu M, Lian R, Hu F, and Wu W
- Subjects
- Administration, Oral, Analysis of Variance, Animals, Area Under Curve, Biological Availability, Cyclosporine blood, Deoxycholic Acid chemistry, Liposomes administration & dosage, Liposomes chemistry, Male, Microscopy, Electron, Transmission, Particle Size, Phosphatidylcholines chemistry, Rats, Rats, Wistar, Cyclosporine administration & dosage, Cyclosporine pharmacokinetics, Deoxycholic Acid administration & dosage
- Abstract
The main purpose of this study was to evaluate liposomes containing a bile salt, sodium deoxycholate (SDC), as oral drug delivery systems to enhance the oral bioavailability of the poorly water-soluble and poorly permeable drug, cyclosporine A (CyA). Liposomes composed of soybean phosphatidylcholine (SPC) and SDC were prepared by a thin-film dispersion method followed by homogenization. Several properties of the liposomes including particle size, polydispersity index, and entrapment efficiency were characterized. The in vitro release of CyA from these liposomes was less than 5% at 12 hours as measured by a dynamic dialysis method. The pharmacokinetic results in rats showed improved absorption of CyA in SPC/SDC liposomes, compared with CyA-loaded conventional SPC/cholesterol (Chol) liposomes and microemulsion-based Sandimmune Neoral(®). The relative oral bioavailability of CyA-loaded SPC/SDC and SPC/Chol liposomes was 120.3% and 98.6%, respectively, with Sandimmun Neoral as the reference. The enhanced bioavailability of CyA was probably due to facilitated absorption by the liposomes containing SDC rather than improved release rate.
- Published
- 2011
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.