scholarly journals Retina-Targeted Delivery of 17β-Estradiol by the Topically Applied DHED Prodrug

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 456
Author(s):  
Katalin Prokai-Tatrai ◽  
Vien Nguyen ◽  
Daniel L. De La Cruz ◽  
Rebecca Guerra ◽  
Khadiza Zaman ◽  
...  
Keyword(s):  
Targeted Delivery ◽  
Ex Vivo ◽  
Estrogen Therapy ◽  
Topical Administration ◽  
The Body ◽  
Female Rats ◽  
Full Potential ◽  
Eye Drops ◽  
17Β Estradiol

The purpose of this study was to explore retina-targeted delivery of 17β-estradiol (E2), a powerful neuroprotectant, by its bioprecursor prodrug 10β,17β-dihydroxyestra-1,4-dien-3-one (DHED) administered as eye drops in animal models. Compared to the parent hormone, DHED displayed increased transcorneal flux ex vivo both with and without the presence of 2-hydroxypropyl-β-cyclodextrin used as a penetration-enhancing excipient in rat, rabbit, and pig. In vitro, the prodrug also showed facile bioactivation to E2 in the retina but not in the cornea. After topical administration to rats and rabbits, peak DHED-derived E2 concentrations reached 13 ± 5 ng/g and 18 ± 7 ng/g in the retina of female rats and rabbits, respectively. However, the prodrug remained inert in the rest of the body and, therefore, did not cause increase in circulating hormone concentration, as well as wet uterine and anterior pituitary weights as typical markers of E2′s endocrine impact. Altogether, our studies presented here have demonstrated the premise of topical retina-selective estrogen therapy by the DHED prodrug approach for the first time and provide compelling support for further investigation into the full potential of DHED for an efficacious and safe ocular neurotherapy.

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito
Keyword(s):  
Antioxidant Capacity ◽  
Dietary Intervention ◽  
Ex Vivo ◽  
The Body ◽  
Dietary Polyphenols ◽  
Enzymatic Antioxidant ◽  
Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

scholarly journals Hyaluronate/black phosphorus complexes as a copper chelating agent for Wilson disease treatment

2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Seong-Jong Kim ◽  
Hye Hyeon Han ◽  
Sei Kwang Hahn
Keyword(s):  
Targeted Delivery ◽  
Wilson Disease ◽  
Copper Ions ◽  
Binding Capacity ◽  
Genetic Disorder ◽  
Chelating Agent ◽  
Black Phosphorus ◽  
The Body ◽  
Copper Binding

Abstract Background Wilson disease (WD) is a genetic disorder of copper storage, resulting in pathological accumulation of copper in the body. Because symptoms are generally related to the liver, chelating agents capable of capturing excess copper ions after targeted delivery to the liver are highly required for the treatment of WD. Methods We developed hyaluronate-diaminohexane/black phosphorus (HA-DAH/BP) complexes for capturing copper ions accumulated in the liver for the treatment of WD. Results HA-DAH/BP complexes showed high hepatocyte-specific targeting efficiency, selective copper capturing capacity, excellent biocompatibility, and biodegradability. HA enhanced the stability of BP nanosheets and increased copper binding capacity. In vitro cellular uptake and competitive binding tests verified targeted delivery of HA-DAH/BP complexes to liver cells via HA receptor mediated endocytosis. The cell viability test confirmed the high biocompatibility of HA-DAH/BP complexes. Conclusion HA-DAH/BP complexes would be an efficient copper chelating agent to remove accumulated copper in the liver for the WD treatment.

scholarly journals Verification of P-Glycoprotein Function at the Dermal Barrier in Diffusion Cells and Dynamic “Skin-On-A-Chip” Microfluidic Device

Pharmaceutics ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 804
Author(s):  
Ágnes Bajza ◽  
Dorottya Kocsis ◽  
Orsolya Berezvai ◽  
András József Laki ◽  
Bence Lukács ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Ex Vivo ◽  
Topical Administration ◽  
Transdermal Absorption ◽  
P Glycoprotein ◽  
Diffusion Cells ◽  
Defensive Role ◽  
Dermal Drug Delivery

The efficacy of transdermal absorption of drugs and the irritation or corrosion potential of topically applied formulations are important areas of investigation in pharmaceutical, military and cosmetic research. The aim of the present experiments is to test the role of P-glycoprotein in dermal drug delivery in various ex vivo and in vitro platforms, including a novel microchip technology developed by Pázmány Péter Catholic University. A further question is whether the freezing of excised skin and age have any influence on P-glycoprotein-mediated dermal drug absorption. Two P-glycoprotein substrate model drugs (quinidine and erythromycin) were investigated via topical administration in diffusion cells, a skin-on-a-chip device and transdermal microdialysis in rat skin. The transdermal absorption of both model drugs was reduced by P-glycoprotein inhibition, and both aging and freezing increased the permeability of the tissues. Based on our findings, it is concluded that the process of freezing leads to reduced function of efflux transporters, and increases the porosity of skin. P-glycoprotein has an absorptive orientation in the skin, and topical inhibitors can modify its action. The defensive role of the skin seems to be diminished in aged individuals, partly due to reduced thickness of the dermis. The novel microfluidic microchip seems to be an appropriate tool to investigate dermal drug delivery.

scholarly journals Extracellular vesicles engineered with valency-controlled DNA nanostructures deliver CRISPR/Cas9 system for gene therapy

2020 ◽  
Vol 48 (16) ◽  
pp. 8870-8882 ◽  
Author(s):  
Jialang Zhuang ◽  
Jizhou Tan ◽  
Chenglin Wu ◽  
Jie Zhang ◽  
Ting Liu ◽  
...  
Keyword(s):  
Extracellular Vesicles ◽  
Ex Vivo ◽  
Primary Liver Cancer ◽  
The Body ◽  
Dna Aptamer ◽  
Great Promise ◽  
Tumor Growth Inhibition ◽  
Specific Cell ◽  
Dna Nanostructures

Abstract Extracellular vesicles (EVs) hold great promise for transporting CRISPR–Cas9 RNA-guided endonucleases (RNP) throughout the body. However, the cell-selective delivery of EVs is still a challenge. Here, we designed valency-controlled tetrahedral DNA nanostructures (TDNs) conjugated with DNA aptamer, and loaded the valency-controlled TDNs on EV surface via cholesterol anchoring for specific cell targeting. The targeting efficacy of different ratios of aptamer/cholesterol from 1:3 to 3:1 in TDNs on decorating EVs was investigated. TDNs with one aptamer and three cholesterol anchors (TDN1) efficiently facilitated the tumor-specific accumulation of the EVs in cultured HepG2 cells and human primary liver cancer-derived organoids, as well as xenograft tumor models. The intracellular delivery of RNP by TDN1-EVs successfully realized its subsequent genome editing, leading to the downregulation of GFP or WNT10B in specific cells. This system was ultimately applied to reduce the protein expression of WNT10B, which presented remarkable tumor growth inhibition in vitro, ex vivo and in vivo, and could be extended to other therapeutic targets. The present study provides a platform for the directional display of aptamer on surface labeling and the EVs-based Cas9 delivery, which provides a meaningful idea for future cell-selective gene editing.

scholarly journals Recent Advances in the Design of Topical Ophthalmic Delivery Systems in the Treatment of Ocular Surface Inflammation and Their Biopharmaceutical Evaluation

Pharmaceutics ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 570 ◽  
Author(s):  
Roseline Mazet ◽  
Josias B. G. Yaméogo ◽  
Denis Wouessidjewe ◽  
Luc Choisnard ◽  
Annabelle Gèze
Keyword(s):  
Ocular Surface ◽  
Ex Vivo ◽  
Immunosuppressive Agents ◽  
Delivery Systems ◽  
Ocular Inflammation ◽  
Limiting Factors ◽  
Common Symptom ◽  
Eye Drops ◽  
Colloidal Systems

Ocular inflammation is one of the most common symptom of eye disorders and diseases. The therapeutic management of this inflammation must be rapid and effective in order to avoid deleterious effects for the eye and the vision. Steroidal (SAID) and non-steroidal (NSAID) anti-inflammatory drugs and immunosuppressive agents have been shown to be effective in treating inflammation of the ocular surface of the eye by topical administration. However, it is well established that the anatomical and physiological ocular barriers are limiting factors for drug penetration. In addition, such drugs are generally characterized by a very low aqueous solubility, resulting in low bioavailability as only 1% to 5% of the applied drug permeates the cornea. The present review gives an updated insight on the conventional formulations used in the treatment of ocular inflammation, i.e., ointments, eye drops, solutions, suspensions, gels, and emulsions, based on the commercial products available on the US, European, and French markets. Additionally, sophisticated formulations and innovative ocular drug delivery systems will be discussed. Promising results are presented with micro- and nanoparticulated systems, or combined strategies with polymers and colloidal systems, which offer a synergy in bioavailability and sustained release. Finally, different tools allowing the physical characterization of all these delivery systems, as well as in vitro, ex vivo, and in vivo evaluations, will be considered with regards to the safety, the tolerance, and the efficiency of the drug products.

scholarly journals Development and Characterization of Potential Ocular Mucoadhesive Nano Lipid Carriers Using Full Factorial Design

Pharmaceutics ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 682
Author(s):  
Eszter L. Kiss ◽  
Szilvia Berkó ◽  
Attila Gácsi ◽  
Anita Kovács ◽  
Gábor Katona ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Harmful Effect ◽  
Cell Junctions ◽  
Toxicity Tests ◽  
Eye Drops ◽  
Corneal Toxicity ◽  
Penetration Tests ◽  
Full Factorial

Generally, topically applied eye drops have low bioavailability due to short residence time and low penetration of the drug. The aim of the present study was to incorporate dexamethasone (DXM) into nano lipid carriers (NLC), which contain mucoadhesive polymer, in order to increase the bioavailability of the drug. A 23 factorial experimental design was applied, in which the three factors were the polymer, the DXM, and the emulsifier concentrations. The samples were analyzed for particle size, zeta potential, polydispersity index, and Span value. The significant factors were identified. The biocompatibility of the formulations was evaluated with human corneal toxicity tests and immunoassay analysis. The possible increase in bioavailability was analyzed by means of mucoadhesivity, in vitro drug diffusion, and different penetration tests, such as in vitro cornea PAMPA model, human corneal cell penetration, and ex vivo porcine corneal penetration using Raman mapping. The results indicated that DXM can be incorporated in stable mucoadhesive NLC systems, which are non-toxic and do not have any harmful effect on cell junctions. Mucoadhesive NLCs can create a depot on the surface of the cornea, which can predict improved bioavailability.

scholarly journals Platelet generation from circulating megakaryocytes is triggered in the lung vasculature

2021 ◽  
Author(s):  
Xiaojuan Zhao ◽  
Dominic Alibhai ◽  
Tony G. Walsh ◽  
Nathalie Tarassova ◽  
Semra Z. Birol ◽  
...  
Keyword(s):  
Blood Cells ◽  
Ex Vivo ◽  
Critical Role ◽  
The Body ◽  
Mouse Lung ◽  
Generation Process ◽  
Large Size ◽  
Large Numbers ◽  
Microfluidic Chamber

Platelets, small hemostatic blood cells, are derived from megakaryocytes, although the generation process is not clear. Only small numbers of platelets have been produced in systems outside the body, where bone marrow and lung are proposed as sites of platelet generation. Here we show that perfusion of megakaryocytes ex vivo through the mouse lung vasculature generates very large numbers of platelets, up to 3,000 per megakaryocyte. Despite their large size, megakaryocytes were able repeatedly to passage through the lung vasculature, leading to enucleation and fragmentation to generate platelets intravascularly. Using the ex vivo lung and a novel in vitro microfluidic chamber we determined the contributions of oxygenation, ventilation and endothelial cell health to platelet generation, and showed a critical role for the actin regulator TPM4.

scholarly journals Development of a Topical Amphotericin B and Bursera graveolens Essential Oil-Loaded Gel for the Treatment of Dermal Candidiasis

2021 ◽  
Vol 14 (10) ◽  
pp. 1033
Author(s):  
Lupe Carolina Espinoza ◽  
Lilian Sosa ◽  
Paulo C. Granda ◽  
Nuria Bozal ◽  
Natalia Díaz-Garrido ◽  
...  
Keyword(s):  
Essential Oil ◽  
Amphotericin B ◽  
Ex Vivo ◽  
In Vitro Release ◽  
Topical Administration ◽  
In Vivo Models ◽  
Topical Gel ◽  
Cutaneous Candidiasis ◽  
Vitro Release

The higher molecular weight and low solubility of amphotericin B (AmB) hinders its topical administration. The aim of this study was to incorporate Bursera graveolens essential oil into an AmB topical gel (AmB + BGEO gel) in order to promote the diffusion of the drug through the skin in the treatment of cutaneous candidiasis. AmB + BGEO gel formulation was determined using a factorial experiment. Physical and chemical parameters, stability, in vitro release profile and ex vivo permeation in human skin were evaluated. In vitro antimicrobial activity was studied using strains of C. albicans, C. glabrata and C. parapsilosis. The tolerability was evaluated using in vitro and in vivo models. AmB + BGEO gel presented appropriate characteristics for topical administration, including pH of 5.85, pseudoplastic behavior, optimal extensibility, as well as high stability and acceptable tolerability. In vitro release studies showed that the formulation releases the drug following a Boltzmann sigmoidal model. Finally, AmB + BGEO gel exhibited higher amount of drug retained inside the skin and lower Minimum Inhibitory Concentration than a formulation sans essential oil. Therefore, these results suggest that the incorporation of B. graveolens essential oil in the formulation could be used as strategy to promote a local effect in the treatment of cutaneous candidiasis.

scholarly journals 11-oxygenated estrogens are a novel class of human estrogens but do not contribute to the circulating estrogen pool

Endocrinology ◽  
2020 ◽  
Author(s):  
Lise Barnard ◽  
Lina Schiffer ◽  
Renate Louw du-Toit ◽  
Jennifer A Tamblyn ◽  
Shiuan Chen ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Cancer Cell Line ◽  
Substantial Contribution ◽  
Cytochrome P450 Aromatase ◽  
Explant Cultures ◽  
Steroid Analysis ◽  
17Β Estradiol ◽  
Estrogen Biosynthesis

Abstract Androgens are the obligatory precursors of estrogens. In humans, classic androgen biosynthesis yields testosterone, thought to represent the predominant circulating active androgen in both men and women. However, recent work has shown that 11-ketotestosterone, derived from the newly described 11-oxygenated androgen biosynthesis pathway, makes a substantial contribution to the active androgen pool in women. Considering that classic androgens are the obligatory substrates for estrogen biosynthesis catalyzed by cytochrome P450 aromatase, we hypothesized that 11-oxygenated androgens are aromatizable. Here we utilize steroid analysis by tandem mass spectrometry to demonstrate that human aromatase generates 11-oxygenated estrogens from 11-oxygenated androgens in three different cell-based aromatase expression systems and in human ex vivo placenta explant cultures. We also show that 11-oxygenated estrogens are generated as a byproduct of the aromatization of classic androgens. We show that 11β-hydroxy-17β-estradiol binds and activates estrogen receptors α and β and that 11β-hydroxy-17β-estradiol and the classic androgen pathway-derived active estrogen, 17β-estradiol, are equipotent in stimulating breast cancer cell line proliferation and expression of estrogen-responsive genes. 11-oxygenated estrogens were, however, not detectable in serum from individuals with high aromatase levels (pregnant women) and elevated 11-oxygenated androgen levels (patients with congenital adrenal hyperplasia or adrenocortical carcinoma). Our data shows that while 11-oxygenated androgens are aromatizable in vitro and ex vivo, the resulting 11-oxygenated estrogens are not detectable in circulation, suggesting that 11-oxygenated androgens function primarily as androgens in vivo.

Sign in / Sign up

Export Citation Format

Share Document