scholarly journals Cell-Penetrating Peptide and Transferrin Co-Modified Liposomes for Targeted Therapy of Glioma

Molecules ◽  
2019 ◽  
Vol 24 (19) ◽  
pp. 3540 ◽  
Author(s):  
Xi Wang ◽  
Yarong Zhao ◽  
Shiyan Dong ◽  
Robert J. Lee ◽  
Dongsheng Yang ◽  
...  

Glioma is one of the most aggressive and common malignant brain tumors. Due to the presence of the blood-brain barrier (BBB), the effectiveness of therapeutics is greatly affected. In this work, to develop an efficient anti-glioma drug with targeting and which was able to cross the BBB, cell-penetrating peptides (R8) and transferrin co-modified doxorubicin (DOX)-loaded liposomes (Tf-LPs) were prepared. Tf-LPs possessed a spherical shape and uniform size with 128.64 nm and their ξ-potential was 6.81 mV. Tf-LPs were found to be stable in serum within 48 h. Uptake of Tf-LPs in both U87 and GL261 cells was analyzed by confocal laser scanning microscopy and by flow cytometry. Tf-LPs were efficiently taken up by both U87 and GL261 cells. Moreover, Tf-LPs exhibited sustained-release. The cumulative release of DOX from Tf-LPs reached ~50.0% and showed excellent anti-glioma efficacy. Histology of major organs, including brain, heart, liver, spleen, lungs and kidney, and the bodyweight of mice, all indicated low toxicity of Tf-LPs. In conclusion, Tf-LPs showed great promise as an anti-glioma therapeutic agent.

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3429 ◽  
Author(s):  
Jia Yao ◽  
Yinyun Ma ◽  
Wei Zhang ◽  
Li Li ◽  
Yun Zhang ◽  
...  

TH(AGYLLGHINLHHLAHL(Aib)HHIL-NH2), a histidine-rich, cell-penetrating peptide with acid-activated pH response, designed and synthesized by our group, can effectively target tumor tissues with an acidic extracellular environment. Since the protonating effect of histidine plays a critical role in the acid-activated, cell-penetrating ability of TH, we designed a series of new histidine substituents by introducing electron donating groups (Ethyl, Isopropyl, Butyl) to the C-2 position of histidine. This resulted in an enhanced pH-response and improved the application of TH in tumor-targeted delivery systems. The substituents were further utilized to form the corresponding TH analogs (Ethyl-TH, Isopropyl-TH and Butyl-TH), making them easier to protonate for positive charge in acidic tumor microenvironments. The pH-dependent cellular uptake efficiencies of new TH analogs were further evaluated using flow cytometry and confocal laser scanning microscopy, demonstrating that ethyl-TH and butyl-TH had an optimal pH-response in an acidic environment. Importantly, the new TH analogs exhibited relatively lower toxicity than TH. In addition, these new TH analogs were linked to the antitumor drug camptothecin (CPT), while butyl-TH modified conjugate presented a remarkably stronger pH-dependent cytotoxicity to cancer cells than TH and the other conjugates. In short, our work opens a new avenue for the development of improved acid-activated, cell-penetrating peptides as efficient anticancer drug delivery vectors.


2007 ◽  
Vol 35 (4) ◽  
pp. 794-796 ◽  
Author(s):  
S. Pujals ◽  
E. Sabidó ◽  
T. Tarragó ◽  
E. Giralt

Proline-rich cell-penetrating peptides, particularly the SAP (sweet arrow peptide), (VRLPPP)3, have been proposed to be useful intracellular delivery vectors, as a result of their lack of cytotoxicity combined with their capacity to be internalized by cells. A common limitation of the therapeutic use of peptides is metabolic instability. In general, peptides are quickly degraded by proteases upon entry into the bloodstream. The use of all-D-peptide derivatives is emerging as a fruitful strategy to circumvent this degradation problem. In this context, we report on the internalization behaviour, protease-resistance enhancement and self-assembly properties of an all-D version of SAP [(vrlppp)3]. The cellular uptake of (vrlppp)3 was evaluated in an in vivo assay in mice. Both flow cytometry and confocal laser-scanning microscopy experiments showed that a carboxyfluoresceinated version of the molecule, carboxyfluorescein–(vrlppp)3, is internalized rapidly in white blood cells and kidney cells. Significant fluorescence was also detected in other organs such as the spleen and the liver. Finally, the toxicity of (vrlppp)3 was examined, and no significant differences in the main biochemical parameters nor in weight were detected compared with controls.


Author(s):  
Kooshan Nayebzadeh ◽  
Jianshe Chen ◽  
SM Mohammad Mousavi

The effect of addition of xanthan gum (0.05, 0.1, 0.15, 0.25% weight/volume) on the formation and rheology of whey protein isolate (WPI)-xanthan gum gels has been investigated at neutral pH. The elastic modulus (G') values of the gelling test were compared. Low concentration of xanthan added (<0.05%,w/v) has a synergistic effect on the gel strength depend on phase separation, so that whey proteins concentrated in their phase and finally mixed gels with xanthan would be stronger than WPI gels. At higher xanthan concentration (> 0.05%, w/v), antagonist effect was observed by reducing the connection between clusters of whey protein by xanthan, so aggregation disruption and a related decrease in (G'). The phase separation microstructure of WPI-stabilized emulsion containing xanthan gum added has been investigated by rheology and confocal laser scanning microscopy. Xanthan was stained with Fluorescein 5(6)-isothiocyanate (FITC). Low xanthan concentration addition lead to depletion flocculation and increasing the xanthan concentration cause to increase the viscoelasticity of aqueous phase, so retarded macroscopic phase separation over period investigated. Structural changes in emulsion were observed in viscoelastic properties of separated phase in the rheometer. The CLSM image shows different phase which have different viscoelastic properties; xanthan-rich region transforms into the spherical shape which has the lowest interfacial energy and gradually two separated ultimately.


Nanomedicine ◽  
2019 ◽  
Vol 14 (16) ◽  
pp. 2227-2241
Author(s):  
Sanyog Jain ◽  
Pragati Khare ◽  
Tushar Date ◽  
Sameer S Katiyar ◽  
Varun Kushwah ◽  
...  

Aim: To design a nanocarrier platform for enhanced transdermal drug permeation. Materials & methods: Gel-based high permeation vesicles (HPVs) were developed and their performance in terms of transdermal flux improvement, in vitro release and skin irritancy was assessed. The mechanistic insights of permeation enhancement were explored using confocal laser scanning microscopy, ATR-FTIR, DSC and P31 NMR. Results: HPVs exhibited as vesicles with uniform size (∼150 nm), extended drug-release profile (∼48 h) and improved transdermal flux. HPVs were also nontoxic and nonirritant to skin. Enhanced vesicle deformability, improved vesicle membrane fluidity and synergistic permeation enhancement action of synergistic combination of permeation enhancer components was found to be responsible for HPV-mediated permeation enhancement. Conclusion: Overall, the study established that HPVs demonstrate a promising therapeutic advantage over conventional transdermal drug carriers.


Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5442
Author(s):  
Sergey S. Ovcherenko ◽  
Olga A. Chinak ◽  
Anton V. Chechushkov ◽  
Sergey A. Dobrynin ◽  
Igor A. Kirilyuk ◽  
...  

RL2 is a recombinant analogue of a human κ-casein fragment, capable of penetrating cells and inducing apoptosis of cancer cells with no toxicity to normal cells. The exact mechanism of RL2 penetration into cells remains unknown. In this study, we investigated the mechanism of RL2 penetration into human lung cancer A549 cells by a combination of electron paramagnetic resonance (EPR) spectroscopy and confocal laser scanning microscopy. EPR spectra of A549 cells incubated with RL2 (sRL2) spin-labeled by a highly stable 3-carboxy-2,2,5,5-tetraethylpyrrolidine-1-oxyl radical were found to contain three components, with their contributions changing with time. The combined EPR and confocal-microscopy data allowed us to assign these three forms of sRL2 to the spin-labeled protein sticking to the membrane of the cell and endosomes, to the spin-labeled protein in the cell interior, and to spin labeled short peptides formed in the cell because of protein digestion. EPR spectroscopy enabled us to follow the kinetics of transformations between different forms of the spin-labeled protein at a minimal spin concentration (3–16 μM) in the cell. The prospects of applications of spin-labeled cell-penetrating peptides to EPR imaging, DNP, and magnetic resonance imaging are discussed, as is possible research on an intrinsically disordered protein in the cell by pulsed dipolar EPR spectroscopy.


Author(s):  
Thomas M. Jovin ◽  
Michel Robert-Nicoud ◽  
Donna J. Arndt-Jovin ◽  
Thorsten Schormann

Light microscopic techniques for visualizing biomolecules and biochemical processes in situ have become indispensable in studies concerning the structural organization of supramolecular assemblies in cells and of processes during the cell cycle, transformation, differentiation, and development. Confocal laser scanning microscopy offers a number of advantages for the in situ localization and quantitation of fluorescence labeled targets and probes: (i) rejection of interfering signals emanating from out-of-focus and adjacent structures, allowing the “optical sectioning” of the specimen and 3-D reconstruction without time consuming deconvolution; (ii) increased spatial resolution; (iii) electronic control of contrast and magnification; (iv) simultanous imaging of the specimen by optical phenomena based on incident, scattered, emitted, and transmitted light; and (v) simultanous use of different fluorescent probes and types of detectors.We currently use a confocal laser scanning microscope CLSM (Zeiss, Oberkochen) equipped with 3-laser excitation (u.v - visible) and confocal optics in the fluorescence mode, as well as a computer-controlled X-Y-Z scanning stage with 0.1 μ resolution.


Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.


TAPPI Journal ◽  
2010 ◽  
Vol 9 (10) ◽  
pp. 7-15
Author(s):  
HANNA KOIVULA ◽  
DOUGLAS BOUSFIELD ◽  
MARTTI TOIVAKKA

In the offset printing process, ink film splitting has an important impact on formation of ink filaments. The filament size and its distribution influence the leveling of ink and hence affect ink setting and the print quality. However, ink filaments are difficult to image due to their short lifetime and fine length scale. Due to this difficulty, limited work has been reported on the parameters that influence filament size and methods to characterize it. We imaged ink filament remains and quantified some of their characteristics by changing printing speed, ink amount, and fountain solution type. Printed samples were prepared using a laboratory printability tester with varying ink levels and operating settings. Rhodamine B dye was incorporated into fountain solutions to aid in the detection of the filaments. The prints were then imaged with a confocal laser scanning microscope (CLSM) and images were further analyzed for their surface topography. Modeling of the pressure pulses in the printing nip was included to better understand the mechanism of filament formation and the origin of filament length scale. Printing speed and ink amount changed the size distribution of the observed filament remains. There was no significant difference between fountain solutions with or without isopropyl alcohol on the observed patterns of the filament remains.


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