Preparation and Evaluation of 6-Maleimidohexanoic Acid Grafted Chitosan Nanoparticles as a Novel Carrier for Intranasal Protein Delivery

2020 ◽  
Vol 859 ◽  
pp. 214-219
Author(s):  
Ekachai Dumkliang ◽  
Tanasait Ngawhirunpat ◽  
Theerasak Rojanarata ◽  
Prasopchai Patrojanasophon ◽  
Boonnada Pamornpathomkul ◽  
...  

In this study, 6-maleimidohexanoic acid grafted chitosan nanoparticles (MHA-CS NPs) were prepared and evaluated the efficiency of intranasal protein delivery as compared with well-known chitosan nanoparticles (CS NPs). Fluorescein isothiocyanate labelled with bovine serum albumin (FITC-BSA) was used as a model protein. The results indicated that both CS NPs and MHA-CS NPs were positively charged NPs before and after protein loading. The condition for optimal protein loading was 1:6 mass ratio of protein/NPs at 1 h incubation period. The optimal formulations of CS NPs and MHA-CS NPs were evaluated on porcine mucosa as ex vivo. The mucoadhesive and permeation properties of FITC-BSA loaded MHA-CS NPs showed a greater than FITC-BSA loaded CS NPs and FITC-BSA solution, respectively. These ex vivo studies present the potential of MHA-CS NPs as a novel carrier for intranasal protein delivery that will be a candidate for in vivo study.

2009 ◽  
Vol 20 (11) ◽  
pp. 1587-1596 ◽  
Author(s):  
Dongqing Luo ◽  
Jianhua Guo ◽  
Fengjie Wang ◽  
Jing Sun ◽  
Guangwu Li ◽  
...  

2020 ◽  
Author(s):  
Stefano Mandija ◽  
Petar I. Petrov ◽  
Jord J. T. Vink ◽  
Sebastian F. W. Neggers ◽  
Cornelis A. T. van den Berg

AbstractFirst in vivo brain conductivity reconstructions using Helmholtz MR-Electrical Properties Tomography (MR-EPT) have been published. However, a large variation in the reconstructed conductivity values is reported and these values differ from ex vivo conductivity measurements. Given this lack of agreement, we performed an in vivo study on eight healthy subjects to provide reference in vivo brain conductivity values. MR-EPT reconstructions were performed at 3 T for eight healthy subjects. Mean conductivity and standard deviation values in the white matter, gray matter and cerebrospinal fluid (σWM, σGM, and σCSF) were computed for each subject before and after erosion of regions at tissue boundaries, which are affected by typical MR-EPT reconstruction errors. The obtained values were compared to the reported ex vivo literature values. To benchmark the accuracy of in vivo conductivity reconstructions, the same pipeline was applied to simulated data, which allow knowledge of ground truth conductivity. Provided sufficient boundary erosion, the in vivo σWM and σGM values obtained in this study agree for the first time with literature values measured ex vivo. This could not be verified for the CSF due to its limited spatial extension. Conductivity reconstructions from simulated data verified conductivity reconstructions from in vivo data and demonstrated the importance of discarding voxels at tissue boundaries. The presented σWM and σGM values can therefore be used for comparison in future studies employing different MR-EPT techniques.


Nutrients ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3566
Author(s):  
Federica Gaiani ◽  
Sara Graziano ◽  
Fatma Boukid ◽  
Barbara Prandi ◽  
Lorena Bottarelli ◽  
...  

The reasons behind the increasing prevalence of celiac disease (CD) worldwide are still not fully understood. This study adopted a multilevel approach (in vitro, ex vivo, in vivo) to assess the potential of gluten from different wheat varieties in triggering CD. Peptides triggering CD were identified and quantified in mixtures generated from simulated gastrointestinal digestion of wheat varieties (n = 82). Multivariate statistics enabled the discrimination of varieties generating low impact on CD (e.g., Saragolla) and high impact (e.g., Cappelli). Enrolled subjects (n = 46) were: 19 healthy subjects included in the control group; 27 celiac patients enrolled for the in vivo phase. Celiacs were divided into a gluten-free diet group (CD-GFD), and a GFD with Saragolla-based pasta group (CD-Sar). The diet was followed for 3 months. Data were compared between CD-Sar and CD-GFD before and after the experimental diet, demonstrating a limited ability of Saragolla to trigger immunity, although not comparable to a GFD. Ex vivo studies showed that Saragolla and Cappelli activated immune responses, although with great variability among patients. The diverse potential of durum wheat varieties in triggering CD immune response was demonstrated. Saragolla is not indicated for celiacs, yet it has a limited potential to trigger adverse immune response.


1994 ◽  
Vol 266 (6) ◽  
pp. H2369-H2373 ◽  
Author(s):  
W. G. Mayhan

The goal of this study was to determine the role of nitric oxide in histamine-induced increases in macromolecular extravasation in the hamster cheek pouch in vivo. We used intravital fluorescent microscopy and fluorescein isothiocyanate dextran (FITC-dextran; mol wt = 70,000 K) to examine extravasation from postcapillary venules in response to histamine before and after application of an enzymatic inhibitor of nitric oxide, NG-monomethyl-L-arginine (L-NMMA; 1.0 microM). Increases in extravasation of macromolecules were quantitated counting the number of venular leaky sites. Histamine (1.0 and 5.0 microM) increased the number of venular leaky sites from zero (basal conditions) to 11 +/- 1 and 21 +/- 2/0.11 cm2, respectively. Superfusion of L-NMMA (1.0 microM) and LY-83583 (1.0 microM) significantly decreased histamine-induced formation of venular leaky sites, whereas L-arginine (100 microM) potentiated histamine-induced formation of venular leaky sites. In contrast, superfusion of NG-monomethyl-D-arginine (1.0 microM) did not inhibit the formation of venular leaky sites in response to histamine. Thus the findings of the present study suggest that production of nitric oxide, and subsequent activation of guanylate cyclase, plays an important role in macromolecular efflux in vivo in response to histamine.


2019 ◽  
Vol 104 (9) ◽  
pp. 3726-3734 ◽  
Author(s):  
Livia Lenzini ◽  
Selene Prisco ◽  
Paul Emmanuel Vanderriele ◽  
Silvia Lerco ◽  
Francesca Torresan ◽  
...  

Abstract Context Accumulating evidence suggests a link between adrenocortical zona glomerulosa and parathyroid gland through mechanisms that remain unexplored. Objectives To test the hypothesis that in vivo angiotensin II blockade affects PTH secretion in patients with hypertension and that aldosterone and angiotensim II directly stimulate PTH secretion ex vivo. Design and Setting We investigated the changes of serum PTH levels induced by oral captopril (50 mg) administration in patients with primary essential hypertension (EH) and with primary aldosteronism (PA) caused by bilateral adrenal hyperplasia (BAH) or aldosterone-producing adenoma (APA), the latter before and after adrenalectomy. We also exposed primary cultures of human parathyroid cells from patients with primary hyperparathyroidism to angiotensin II (10−7 M) and/or aldosterone (10−7 M). Results Captopril lowered PTH levels (in nanograms per liter) both in patients with EH (n = 63; 25.9 ± 8.3 baseline vs 24.4 ± 8.0 postcaptopril, P < 0.0001) and in patients with APA after adrenalectomy (n = 27; 26.3 ± 11.6 vs 24.0 ± 9.7 P = 0.021). However, it was ineffective in patients with full-blown PA caused by APA and BAH. In primary culture of human parathyroid cells, both aldosterone (P < 0.001) and angiotensin II (P = 0.002) markedly increased PTH secretion from baseline, by acting through mineralocorticoid receptor and angiotensin type 1 receptor, as these effects were abolished by canrenone and irbesartan, respectively. Conclusion These results collectively suggest an implication of the renin-angiotensin-aldosterone system in PTH regulation in humans, at least in PTH-secreting cells obtained from parathyroid tumors. Moreover, they further support the concept that mild hyperparathyroidism is a feature of human PA that is correctable with adrenalectomy.


Pharmaceutics ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 814
Author(s):  
Momoko Kitaoka ◽  
Atsushi Oka ◽  
Masahiro Goto

An increasing number of protein vaccines have been researched for cancer, inflammation, and allergy therapies. Most of the protein therapeutics are administered through injection because orally-administered proteins are metabolized by the digestive system. Although transdermal administration has received increasing attention, the natural barrier formed by the skin is an obstacle. Monoolein is a common skin penetration enhancer that facilitates topical and transdermal drug delivery. Conventionally, it has been used in an aqueous vehicle, often with polyhydric alcohols. In the current study, monoolein was dissolved in an oil vehicle, isopropyl myristate, to facilitate the skin permeation of powder proteins. The skin permeabilities of the proteins were examined in-vivo and ex-vivo. Monoolein concentration-dependently enhanced the skin permeation of proteins. The protein permeability correlated with the zeta potential of the macromolecules. Dehydration of the stratum corneum (SC), lipid extraction from the SC, and disordering of ceramides caused by monoolein were demonstrated through Fourier transform infrared spectroscopic analysis and small-angle X-ray scattering analysis. An antigen model protein, ovalbumin from egg white, was delivered to immune cells in living mice, and induced antigen-specific IgG antibodies. The patch system showed the potential for transdermal vaccine delivery.


2012 ◽  
Vol 157 (3) ◽  
pp. 383-390 ◽  
Author(s):  
S. Al-Qadi ◽  
A. Grenha ◽  
D. Carrión-Recio ◽  
B. Seijo ◽  
C. Remuñán-López

Blood ◽  
2006 ◽  
Vol 108 (6) ◽  
pp. 1911-1918 ◽  
Author(s):  
Matt W. Goschnick ◽  
Lai-Man Lau ◽  
Janet L. Wee ◽  
Yong S. Liu ◽  
P. Mark Hogarth ◽  
...  

AbstractWe investigated the role of the hematopoietic-specific tetraspanin superfamily member, TSSC6, in platelet function using wild-type mice and TSSC6-deficient mice. TSSC6 is expressed on the surface of murine platelets and is up-regulated by thrombin stimulation, indicating an intracellular pool of TSSC6. Immunoprecipitation/Western blot studies reveal a constitutive physical association of TSSC6 with the integrin αIIbβ3 complex under strong detergent conditions. In vivo evaluation of hemostasis by tail bleeding revealed increased bleeding time, volume of blood lost, and evidence of tail rebleeds in TSSC6 null mice, indicating unstable hemostasis. Using ex vivo techniques, we showed that TSSC6-deficient platelets exhibited impaired kinetics of clot retraction, platelet aggregation at lower doses of PAR-4, and collagen and platelet spreading on fibrinogen in the presence of normal integrin αIIbβ3 expression. TSSC6-deficient platelets showed normal alpha granule secretion, normal “insideout” integrin αIIbβ3 signaling (fluorescein isothiocyanate [FITC]–fibrinogen and JON/A binding), and normal platelet adhesion on fibrinogen. Furthermore, we show that absence of platelet TSSC6 affects the secondary stability of arterial thrombi in vivo upon vascular injury. These data demonstrate that TSSC6 appears to regulate integrin αIIbβ3 “outside-in” signaling events in platelets and is necessary for stability of arterial thrombi in vivo.


1990 ◽  
Vol 63 (02) ◽  
pp. 271-274 ◽  
Author(s):  
J Van Ryn-McKenna ◽  
L Cai ◽  
F A Ofosu ◽  
J Hirsh ◽  
M R Buchanan

SummaryIt has been suggested that protamine sulfate is a poor antidote for the bleeding side-effeets of low molecular weight heparins (LMWHs) in vivo, since protamine sulfate does not completely neutralize the anti-factor Xa activity of LMWHs in vitro or ex vivo. Therefore, we performed experiments to compare directly the abilities of protamine sulfate to neutralize the anticoagulant activities of the LMWH, enoxaparine, and unfractionated heparin ex vivo, with its ability to neutralize the bleeding side-effeets of both compounds in vivo. Bleeding was measured as the amount of blood lost from 5 cuts made in rabbits ears before and after treatment with enoxaparine or unfractionated heparin ± protamine sulfate. Plasma anti-factor Xa and anti-thrombin activities ex vivo, were measured chromogenically. Doses of 400 and 1,500 anti-factor Xa U/kg of heparin and enoxaparine, respectively, were required to enhance blood loss to the same extent. Protamine sulfate completely neutralized blood loss induced by both compounds, but did not neutralize the anti-factor Xa nor antithrombin activities ex vivo. We conclude that protamine sulfate is an effective antidote for the bleeding side-effeets of enoxaparine and unfractionated heparin, despite its inability to completely neutralize their anticoagulant activities.


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