References of "Piel, Géraldine"
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See detailLiposome production by innovative method using supercritical fluids
Penoy, Noémie ULiege; Bigazzi, William ULiege; Piel, Géraldine ULiege et al

Scientific conference (2018, December 19)

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See detailEnhancement of skin penetration of lipid-based nanocarriers
Bellefroid, Coralie ULiege; Lechanteur, Anna ULiege; Evrard, Brigitte ULiege et al

Scientific conference (2018, December 19)

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See detailCationic Liposomes Carrying siRNA: Impact of Lipid Composition on Physicochemical Properties, Cytotoxicity and Endosomal Escape
Lechanteur, Anna ULiege; Sanna, Vincent; Duchemin, Amandine ULiege et al

Poster (2018, August)

In recent year, cationic liposomes have gained a lot of attention for siRNA delivery using different local routes of administration as the vaginal [1] or the pulmonary routes. However, lipoplexes have to ... [more ▼]

In recent year, cationic liposomes have gained a lot of attention for siRNA delivery using different local routes of administration as the vaginal [1] or the pulmonary routes. However, lipoplexes have to face several biological and intracellular barriers before releasing the genetic cargo. In this study, we focus our effort on intracellular barriers and more specifically on endosomal escape and cytosolic delivery of siRNA as well as on the cytotoxicity due to cationic lipids. Indeed, we have previously demonstrated that the surface charge of liposomes composed of the cationic lipid DOTAP is correlated to the induction of cytotoxicity [2]. In the present study, we have investigated the impact of different cationic lipids and co-lipids on the cytotoxicity and also on the endosomal escape of siRNA by flow cytometry, qRT-PCR and Western Blot assays [3]. To address these issues, we developed four liposomal formulations composed of two different cationic lipids (DOTAP and DC-Cholesterol) and different ratio of co-lipids (cholesterol and DOPE). Formulations were DOTAP/Cholesterol/DOPE 1/0.75/0.5, DOTAP/Cholesterol/DOPE 1/0.5/0.5, DOTAP/DOPE 1/1 and DC-Cholesterol/DOPE 1/1. Each type of liposomes were complexed to siRNA at six different N/P molar ratios and physico-chemical properties were characterized in terms of Z-average size, Zeta potential and complexation efficiency by gel retardation assay. Consequently, three N/P ratios (2.5, 5 and 10) were selected for in vitro experiments on A549 cells. First, we studied the cell viability of A549 cells treated during 24 h with liposomes complexed to inactive siRNA at different N/P molar ratios at siRNA concentrations of 40 and 100 nM. We have shown that the cytotoxicity is influenced by the N/P ratio, the concentration of cationic lipid as well as the nature of the cationic lipid. Secondly, the cellular uptake were evaluated by flow cytometry using the dry Trypan Blue® to quench the external fluorescence. Despite the fact the transfection rate were not significantly different, the mRNA knock-down efficiency were not similar between formulations. Liposomes containing 50% of DOPE induced a mRNA silencing of around 80% as well as the protein knock-down. This study allowed to highlight crucial parameters in order to develop lipoplexes which are safe and induce an efficient intracytoplasmic release of siRNA. Acknowledgments: The authors thank the Belgium National Fund for Scientific Research (FNRS, http://www.frs-fnrs.be) –Télévie for financial support and the Giga Cell Imaging and Flow Cytometry Platform for their collaboration. Anna Lechanteur is a FNRS-Télévie post-doctoral researcher. Amandine Duchemin is a FRIA FNRS Fellow. Denis Mottet is a FNRS Research Associate. References: 1. Lechanteur, A., Furst, T. Delvenne, P. et al., Promoting vaginal distribution of E7 and MCL-1 siRNA-silencing nanoparticles for cervical cancer treatment Molecular Pharmaceutics, 2017. 14: p. 1706-1717. 2. Lechanteur, A., Furst, T. Evrard, B. et al., PEGylation of lipoplexes: The right balance between cytotoxicity and siRNA effectiveness. Eur J Pharm Sci, 2016. 93: p. 493-503. 3. Lechanteur, A., Sanna, V. Duchemin, A. et al., Cationic Liposomes Carrying siRNA: Impact of Lipid Composition on Physicochemical Properties, Cytotoxicity and Endosomal Escape. Nanomaterials (Basel), 2018. 8(270): p. 1-12. [less ▲]

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See detailBarriers and challenges to nanomedicine developments
Piel, Géraldine ULiege

Conference (2018, July 12)

Nanotechnology has made important contributions to oncology over the past decades. Although encapsulating drugs in liposomes has been broadly shown to improve PK and biodistribution, as yet no marketed ... [more ▼]

Nanotechnology has made important contributions to oncology over the past decades. Although encapsulating drugs in liposomes has been broadly shown to improve PK and biodistribution, as yet no marketed liposomal therapeutic agents have exhibited an overall survival benefit when directly compared with the conventional parent drug. The lack of or limited gain in overall survival challenges the field to improve patient survival further with more effective nanomedicine-based therapies. Up to now, nanomedicine research projects have been structured to adapt the physico-chemical parameters of a delivery system – loading, chemistry, size, charge, surface modification – to control its in vivo behaviour. Many experimental scientists, pharmacologists and nanotechnology engineers have held to the premise that solid tumors consist of uniform tissues. In fact, human tumors are highly diverse and heterogeneous; they vary in pathological characteristics, size less than 1 mm to above 10 cm, metastatic or primary tumor… Even experimental rodent tumors and implanted tumors, or those of orthotopic or autochthonous origin, exhibit these different characteristics. The complex physiological and pathophysiological interactions between NPs and biological systems, which are unique to individual patients, have hampered the clinical translation of cancer nanomedicine Therefore, the effects of heterogeneity of human tumors should be better understood. This conference will discuss some of these complexities to understand and consider for effective nanomedicine development. [less ▲]

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See detailAssessment of skin penetration of classical and deformable liposomes
Bellefroid, Coralie ULiege; Lechanteur, Anna ULiege; Evrard, Brigitte ULiege et al

Conference (2018, July 12)

The skin is the largest organ of the human body representing an alternative route of administration by providing an easy and pain-free drug delivery option. Cutaneous drug delivery is not associated with ... [more ▼]

The skin is the largest organ of the human body representing an alternative route of administration by providing an easy and pain-free drug delivery option. Cutaneous drug delivery is not associated with a significant drug loss compared to systemic administration due to low enzymatic degradation and a negligible clearance. Moreover, the systemic toxicity resulting from cutaneous application is limited and side effects are easy to observe and to handle [1]. Thanks to these advantages there is a great interest in using the skin as a route of administration. Besides physical and active methods involving the disruption of the stratum corneum (SC) to increase the penetration of drugs in the underlying layers, passive methods using of non-viral vectors, particularly lipid-based nanovectors, is one of the most attractive method [2]. They were developed to increase topical macromolecules penetration through the SC barrier and to promote the intracellular delivery of large molecules such as nucleic acids. However, it has become obvious that conventional liposomes do not promote the skin penetration without enhancement techniques [3]. The aim of this study is to assess the skin penetration of lipid-based nanocarriers according to their composition. The skin penetration of conventional liposomes was compared to the penetration of deformable liposomes with ethanol and/or edge activators (EA). 25% (w/w) of ethanol was added to conventional liposomes (DOTAP/DOPE) to form ethosomes. Sodium Cholate and Tween®80 were used as EA to develop deformable liposomes. Formulations were characterized in terms of size, polydispersity index and surface charge. Ex vivo skin penetration experiment were performed using pig ear skin on Franz cells. In order to visualize the penetration through the skin using confocal microscopy, nanocarriers were fluorescently labeled with a fluorescent lipid (NBD-PC). A kinetic of application was performed (from 3h to 24h) and each condition was done with or without tape stripping. In this study, we showed that all the formulations were not able to penetrate the skin, even for deformable formulations. However, when the SC was removed, formulations containing ethanol allowed penetration into the epidermis. Moreover, the addition of an EA seems to encourage deeper penetration. Acknowledgments: Authors thank the Walloon Region and FEDER for financial supports. References: 1. Zakrewsky, M., S. Kumar, and S. Mitragotri, Nucleic acid delivery into skin for the treatment of skin disease: Proofs-of-concept, potential impact, and remaining challenges. J Control Release, 2015. 219: p. 445-56. 2. Geusens, B., et al., Lipid-mediated gene delivery to the skin. Eur J Pharm Sci, 2011. 43(4): p. 199-211. 3. Sala, M., et al., Lipid nanocarriers as skin drug delivery systems: Properties, mechanisms of skin interactions and medical applications. Int J Pharm, 2018. 535(1-2): p. 1-17. [less ▲]

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See detailCationic Liposomes Carrying siRNA: Impact of Lipid Composition on Physicochemical Properties, Cytotoxicity and Endosomal Escape
Lechanteur, Anna ULiege; Sanna, Vincent; Duchemin, Amandine ULiege et al

in Nanomaterials (2018), 8(5),

Abstract: In recent year, cationic liposomes have gained a lot of attention for siRNA delivery. Despite this, intracellular barriers as endosomal escape and cytosolic delivery of siRNA still represent a ... [more ▼]

Abstract: In recent year, cationic liposomes have gained a lot of attention for siRNA delivery. Despite this, intracellular barriers as endosomal escape and cytosolic delivery of siRNA still represent a challeng, as well as the cytotoxicity due to cationic lipids. To address these issues, we developed four liposomal formulations, composed of two different cationic lipids (DOTAP and DC-Cholesterol) and different ratio of co-lipids (cholesterol and DOPE). The objective is to dissect these impacts on siRNA efficacy and cytotoxicity. Liposomes were complexed to siRNA at six different N/P molar ratios, physico-chemical properties were characterized, and consequently, N/P 2.5, 5 and 10 were selected for in vitro experiments. We have shown that cytotoxicity is influenced by the N/P ratio, the concentration of cationic lipid, as well as the nature of the cationic lipid. For instance, cell viability decreased by 70% with liposomes composed of DOTAP/Cholesterol/DOPE 1/0.75/0.5 at a N/P ratio 10, whereas the same formulation at a N/P ratio of 2.5 was safe. Interestingly, we have observed differences in terms of mRNA knock-down efficiency, whereas the transfection rate was quite similar for each formulation. Liposomes containing 50% of DOPE induced a mRNA silencing of around 80%. This study allowed us to highlight crucial parameters in order to develop lipoplexes which are safe, and which induce an efficient intracytoplasmic release of siRNA. [less ▲]

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See detailCationic Liposomes Carrying siRNA: Impact of Lipid Composition on Physicochemical Properties, Cytotoxicity and Endosomal Escape
Lechanteur, Anna ULiege; Sanna, Vincent; Duchemin, Amandine ULiege et al

in Cationic liposomes carrying siRNA: impact of lipid composition on physicochemical properties, cytotoxicity and endosomal escape (2018, April)

In recent year, cationic liposomes have gained attention for siRNA delivery using different local routes of administration as the vaginal [Lechanteur et al, Mol Pharm.2017] or the pulmonary routes ... [more ▼]

In recent year, cationic liposomes have gained attention for siRNA delivery using different local routes of administration as the vaginal [Lechanteur et al, Mol Pharm.2017] or the pulmonary routes. However, lipoplexes have to face several biological and intracellular barriers before releasing the genetic cargo. In this study, we focus our effort on intracellular barriers and more specifically on endosomal escape and cytosolic delivery of siRNA as well as on the cytotoxicity due to cationic lipids. Indeed, we have previously demonstrated that the surface charge of liposomes composed of the cationic lipid DOTAP is correlated to the induction of cytotoxicity [Lechanteur et al. EJPS.2016]. In the present study, we have investigated the impact of different cationic lipids and co-lipids on the cytotoxicity and also on the endosomal escape of siRNA by flow cytometry, qRT-PCR and Western Blot assays [Lechanteur et al. Nanomat.2018]. To address these issues, we developed four liposomal formulations composed of two different cationic lipids (DOTAP and DC-Cholesterol) and different ratio of co-lipids (cholesterol and DOPE). Formulations were DOTAP/Cholesterol/DOPE 1/0.75/0.5, DOTAP/Cholesterol/DOPE 1/0.5/0.5, DOTAP/DOPE 1/1 and DC-Cholesterol/DOPE 1/1. Each type of liposomes were complexed to siRNA at six different N/P molar ratios and physico-chemical properties were characterized in terms of Z-average size, Zeta potential and complexation efficiency. Consequently, three N/P ratios (2.5, 5 and 10) were selected for in vitro experiments on A549 cells. We studied the cell viability of cells with liposomes complexed to inactive siRNA at different N/P molar ratios at two siRNA concentrations. We have shown that the cytotoxicity is influenced by the N/P ratio, the concentration of cationic lipid as well as the nature of the cationic lipid. The cellular uptake were evaluated using the dye Trypan Blue® to quench the external fluorescence. Despite the fact the transfection rate were not significantly different, the mRNA knock-down efficiency were not similar between formulations. Liposomes containing 50% of DOPE induced a mRNA silencing of around 80% as well as the protein knock-down. This study allowed to highlight crucial parameters in order to develop lipoplexes which are safe and induce an efficient intracytoplasmic release of siRNA. [less ▲]

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See detailDevelopment of injectable liposomes and drug-in-cyclodextrin-in-liposome formulations encapsulating estetrol to prevent cerebral ischemia of premature babies.
Palazzo, Claudio; Laloy, Julie; Delvigne, Anne Sophie et al

in European Journal of Pharmaceutical Sciences (2018), 9(127), 52-59

Neonatal Hypoxic-Ischemic Encephalopathy (HIE), a brain disease due to brain hypoxia along with ischemia and reduced cerebral blood flow, is one of the primary reasons of severe injury among babies ... [more ▼]

Neonatal Hypoxic-Ischemic Encephalopathy (HIE), a brain disease due to brain hypoxia along with ischemia and reduced cerebral blood flow, is one of the primary reasons of severe injury among babies prematurely born. No efficacy treatment is available to the present day. Estetrol (E4), a major estradiol metabolite, has an important role in the brain development and protection. The aim of this study is to develop new injectable liposome and drug-in-cyclodextrin-in-liposome (DCL) formulations, encapsulating E4 in order to enhance its crossing through the blood-brain barrier (BBB). Liposome and DCL formulations were prepared and were physiochemically characterized. Stability in foetal bovine serum (FBS) was evaluated. LDH and MTS tests on endothelial, neuronal and BBB model cells, as well as hemocompatibility of the nanovectors were performed in vitro. In vitro BBB passage was evaluated using human BBB cell line (hCMEC/D3). All the formulations had average particle size below 150 nm, polydispersity index below 0.10 and ζ potential around + 30 mV. The encapsulation efficacy for liposomes was between 3% and 10% while those of DCL are between 15% and 35%. The effect of liposome and DCL formulations on cell viability and integrity was evaluated. The results showed no toxic effects on all the tested cell lines. Hemocompatibility tests showed no hemolysis, platelet aggregation or effects on coagulation, confirming the possibility of the formulations to be intravenously administrated. BBB passage tests highlighted the capability of the formulations to pass the BBB and reach the brain. Therefore, the formulations are promising drug delivery system to target estrogens to the brain, due to their physiochemical characteristics. [less ▲]

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See detailInclusion of 17β-estradiol into liposome prevent the activation of membrane initiated signaling of ERalpha
Gallez, Anne ULiege; Palazzo, Claudio; Evrard, Brigitte ULiege et al

Poster (2018)

Estrogens are implicated in many physiological and pathological processes thanks to their interaction with estrogen receptors (ERs). The estrogen receptor alpha (ERα) controls reproduction, normal mammary ... [more ▼]

Estrogens are implicated in many physiological and pathological processes thanks to their interaction with estrogen receptors (ERs). The estrogen receptor alpha (ERα) controls reproduction, normal mammary gland development and breast cancer progression. The activation of ERα by estrogens, especially by 17β-estradiol (E2), leads to two major pathways: (1) the genomic effects associated to the transcriptional activity of the ERα and (2) the MISS (Membrane Initiated Steroid Signaling) effects related to the induction of fast signaling pathways occurring when ERα is anchored to the plasma membrane. Liposome are small non-toxic and biodegradable vectors widely studied for treatment of pathologies, like multiple sclerosis, Parkinson and Alzheimer disease and cancer. The encapsulation of several types of molecules (proteins, DNA and steroids), the protection of the activity and the improvement of the pharmacokinetic properties of these compounds represent the main advantages of liposome’s use. However, the impact of the encapsulation on molecular mechanisms is not yet established. As a proof of concept, we evaluate the impact of E2 inclusion into liposome (named POPC E2) in vitro and in vivo on ERα signaling pathway activation. [less ▲]

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See detailEnhanced and preferential internalization of lipid nanocapsules into human glioblastoma cells: effect of a surface-functionalizing NFL peptide
Karim, Reatul; Lepeltier, Elise; Esnault, Lucille et al

in Nanoscale (2018)

Increasing intracellular drug concentration using nanocarriers can be a potential strategy to improve efficacy against glioblastoma (GBM). Here, the fluorescent-labelled NFL-TBS.40-63 peptide (fluoNFL ... [more ▼]

Increasing intracellular drug concentration using nanocarriers can be a potential strategy to improve efficacy against glioblastoma (GBM). Here, the fluorescent-labelled NFL-TBS.40-63 peptide (fluoNFL) concentration on lipid nanocapsule (LNC) was studied to enhance nanovector internalization into human GBM cells. The LNC surface-functionalization with various fluoNFL concentrations was performed by adsorption. LNC size and surface charge altered gradually with increasing peptide concentration, but their complement protein consumption remained low. Desorption of fluoNFL from LNC surface was found to be slow. Furthermore, it was observed that the rate and extent of LNC internalization in the U87MG human glioblastoma cells were dependent on the surface-functionalizing fluoNFL concentration. In addition, we showed that the uptake of fluoNFL-functionalized LNCs was preferential towards U87MG cells compared to healthy human astrocytes. The fluoNFL-functionalized LNC internalization into the U87MG cells was energy-dependent and occurred possibly by macropinocytosis, clathrin-mediated and caveolin-mediated endocytosis. A new ferrocifen-type molecule (FcTriOH), as potent anticancer candidate, was then encapsulated in the LNCs and the functionalization improved its in vitro efficacy compared to other tested formulations against U87MG cells. In the preliminary study, on subcutaneous human GBM tumor model in nude mice, a significant reduction of relative tumor volume was observed at one week after the second intravenous injection with FcTriOH-loaded LNCs. These results showed that enhancing NFL peptide concentration on LNC surface is a promising approach for increased and preferential nanocarrier internalization into human GBM cells, and the FcTriOH-loaded LNCs are promising therapy approach for GBM. [less ▲]

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See detailPromoting vaginal distribution of two active siRNA-complexed in liposomes for cervical cancer treatment
Lechanteur, Anna ULiege; Furst, Tania; Delvenne, Philippe ULiege et al

Conference (2017, December 07)

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See detailPromoting vaginal distribution of two active siRNA-complexed in liposomes for cervical cancer treatment
Lechanteur, Anna ULiege; Furst, Tania; Delvenne, Philippe ULiege et al

Conference (2017, December 05)

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See detailPulmonary delivery of a liposome formulation encapsulating a natural flavonoid in the treatment of lung cancer
Cao, Martine ULiege; Karim, Reatul ULiege; CATALDO, Didier ULiege et al

Poster (2017, December)

Development of new chemotherapeutic agents remains a continuing challenge in oncology, as the disease represents the major cause of morbidity and mortality worldwide. Lung cancer is the most frequently ... [more ▼]

Development of new chemotherapeutic agents remains a continuing challenge in oncology, as the disease represents the major cause of morbidity and mortality worldwide. Lung cancer is the most frequently diagnosed cancer and was the leading cause of deaths due to cancer in the last recent years [1]. In Belgium, one cancer out of four was associated to lung cancer in 2013 [2]. There is therefore an urgent need to discover new chemotherapeutic options. To date, the treatment of patients with lung cancer is a combination of surgery, radiotherapy and/or oral or IV chemotherapy. But there is currently no direct pulmonary treatment to administer chemotherapeutic drugs. Our project seeks to develop an original formulation for inhalation based on liposomes and a natural compound from the flavonoid class to treat lung cancer. Previous work carried out in our laboratory showed that liposomes with a positive zeta potential and composed of DPPC, DOPE, DC-Cholesterol and DSPE-PEG2000 displayed superior entrapping rate of the active flavonoid. Starting from that formulation, we worked on the optimization with different types and proportions of lipids, and characterized the liposomes in terms of size, PDI, charge, encapsulation efficiency and drug loading capacity. The in vitro therapeutic efficacy and cytotoxicity of the formulations were validated by MTT assays on a lung cancer cell line (LLC - mouse Lewis lung carcinoma cells) and on a lung control cell line (MLE12). The formulation giving the optimal characteristics and response on cells will be then evaluated in vivo for its tumor potential and toxicity in a relevant experimental lung cancer mouse model. [less ▲]

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See detailDevelopment and evaluation of injectable nanosized drug delivery systems for apigenin
Karim, Reatul ULiege; Palazzo, Claudio ULiege; Laloy, Julie et al

in International Journal of Pharmaceutics (2017), 532(2), 757-768

The purpose of this study was to develop different injectable nanosized drug delivery systems (NDDSs) i.e. liposome, lipid nanocapsule (LNC) and polymeric nanocapsule (PNC) encapsulating apigenin (AG) and ... [more ▼]

The purpose of this study was to develop different injectable nanosized drug delivery systems (NDDSs) i.e. liposome, lipid nanocapsule (LNC) and polymeric nanocapsule (PNC) encapsulating apigenin (AG) and compare their characteristics to identify the nanovector(s) that can deliver the largest quantity of AG while being biocompatible. Two liposomes with different surface characteristics (cationic and anionic), a LNC and a PNC were prepared. A novel tocopherol modified poly(ethylene glycol)-b-polyphosphate block-copolymer was used for the first time for the PNC preparation. The NDDSs were compared by their physicochemical characteristics, AG release, storage stability, stability in serum, complement consumption and toxicity against a human macrovascular endothelial cell line (EAhy926). The diameter and surface charge of the NDDSs were comparable with previously reported injectable nanocarriers. The NDDSs showed good encapsulation efficiency and drug loading. Moreover, the NDDSs were stable during storage and in fetal bovine serum for extended periods, showed low complement consumption and were non-toxic to EAhy926 cells up to high concentrations. Therefore, they can be considered as potential injectable nanocarriers of AG. Due to less pronounced burst effect and extended release characteristics, the nanocapsules could be favorable approaches for achieving prolonged pharmacological activity of AG using injectable NDDS. [less ▲]

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See detailIdentification and quantitation of intact virus-like particles of human papillomavirus (HPV-VLP) using capillary electrophoresis
Bettonville, Virginie ULiege; Nicol, Jérôme; Furst, Tania et al

Conference (2017, September 19)

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See detailWhole blood microsampling for the quantitation of estetrol without derivatization by liquid chromatography-tandem mass spectrometry
Nys, Gwenaël ULiege; Gallez, Anne ULiege; Kok, Miranda ULiege et al

in Journal of Pharmaceutical and Biomedical Analysis (2017), 140

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