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Chemo-Immunotherapy of Murine Cancer Using Alpha Tocopheryl Succinate and Non-Matured Dendritic CellsRamanathapuram, Lalitha January 2006 (has links)
The search for anticancer drugs that are tumor specific and cause minimal side effects and the development of effective cancer vaccines are focal points of cancer therapy today. Dendritic cells (DC) are considered potential candidates for cancer immunotherapy due to their ability to process and present antigens to T cells and stimulate immune responses. However, DC-based vaccines have exhibited minimal effectiveness in abrogating established tumors in mice and human cancer patients. The use of appropriate adjuvants can enhance the efficacy of DC-based cancer vaccines in treating established tumors.The studies in this dissertation describe a chemo-immunotherapeutic strategy, which combines a Vitamin E analog, a-tocopheryl succinate (a-TOS) that is selectively toxic to tumor cells with non-antigen pulsed, non-matured dendritic cells (nmDC) to treat established murine lung and breast tumors. The results demonstrate that a-TOS synergizes with nmDC to inhibit the growth of established tumors and significantly reduce residual lung metastasis when therapy is initiated after surgical removal of primary tumors. This outcome was correlated with increased IFN-g and IL-4 production by splenic and draining lymph node lymphocytes. In trying to understand the mechanism of action of the combination treatment we observed that a-TOS treated tumor cells factors cause DC maturation in vitro. This effect is mediated in part by heat shock proteins 60, 70 and 90 induced during a-TOS-mediated killing of tumor cells. This study demonstrates the potential usefulness of a-tocopheryl succinate, an agent non-toxic to normal cell types, as an adjuvant to augment the effectiveness of DC-based vaccines in treating cancer.
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Pharmaceutical Properties of Nanoparticulate Formulation Composed of TPGS and PLGA for Controlled Delivery of Anticancer DrugMu, L., Chan-Park, Mary Bee-Eng, Yue, Chee Yoon, Feng, S.S. 01 1900 (has links)
A suitable management of the pharmaceutical property is needed and helpful to design a desired nanoparticulate delivery system, which includes the carrier nature, particle size and size distribution, morphology, surfactant stabiliser according to the technique applied, drug-loading ratio and encapsulation efficiency, surface property, etc. All will influence the in vitro release, in vivo behaviour and tissue distribution of administered particulate drug loaded nanoparticles. The main purpose of the present work was to determine the effect of drug loading ratio when employing TPGS as surfactant stabiliser and/or matrix material to improve the nanoparticulate formulation. The model drug employed was paclitaxel. / Singapore-MIT Alliance (SMA)
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Transport of Deuterium-Labeled Tocopherols During PregnancyAcuff, Robert V., Dunworth, Robert G., Webb, Lisa W., Lane, Jonathan R. 01 January 1998 (has links)
With use of deuterium-labeled isotopes of RRR-and all-rac-α-tocopheryl acetate, the transport of vitamin E in pregnancy was evaluated to determine whether the placenta discriminates between these compounds. Fifteen pregnant subjects were recruited 5 d before delivery to receive 15, 30, 75, 150, or 300 mg vitamin E/d in capsules containing d3-RRR-α-tocopheryl acetate and d6-all-rac-α-tocopheryl acetate (1:1, by wt). Maternal blood was obtained before dosing, at hospital admission, and at parturition. Cord blood samples were obtained at parturition. Deuterium-labeled and unlabeled tocopherol contents were determined by gas chromatography-mass spectrometry in plasma and lipoproteins (chylomicrons, VLDL, LDL, and HDL). Maternal plasma and lipoproteins obtained at delivery had higher concentrations of d3-RRR-α- tocopherol than d6-all-rac-α-tocopherol regardless of the vitamin E dose administered (P < 0.05). Cord plasma at delivery also had higher concentrations of d3-RRR-α-tocopherol than d6-all-rac-α-tocopherol in plasma irrespective of the dose administered (P < 0.05). In lipoproteins isolated from cord blood, tocopherol concentrations were greatest in the HDL fraction (P < 0.05), whereas in maternal blood they were greatest in the LDL fraction (P < 0.05). We conclude that the placental-fetal unit, the fetal liver, or both further discriminate between RRR- and all-rac-α-tocopherol.
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Mechanistic Validation of Potential Anti-Breast Cancer TherapeuticsChuang, Hsiao-Ching 27 June 2012 (has links)
No description available.
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Influência da adição in vivo de vitamina E e de métodos de abate nos atributos de qualidade de filés de tilápiaOtani, Fabrizia Sayuri [UNESP] 12 February 2009 (has links) (PDF)
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otani_fs_me_jabo.pdf: 297413 bytes, checksum: 56eab3cec2d3b86c444c71f545ccac0e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Este trabalho objetivou avaliar a influência da vitamina E pela suplementação por meio da dieta, em peixes submetidos a dois métodos de abate (imersão em água gelada e sangria), nos atributos de qualidade de filés congelados de tilápia (Oreochromis spp.). Peixes, com peso médio inicial de 340 g, foram alimentados por um período de nove semanas com três dietas isocalóricas (3264,09 kcal ED/kg) e isoprotéicas (24,8% PD), diferindo na adição de 100 mg/kg de ração de α-tocoferol (grupo TO), 100 mg de princípio ativo/kg de ração de acetato de α- tocoferil (grupo AC), e sem adição de vitamina E (grupo controle – CO). Ao final do período de alimentação, os peixes foram abatidos pelos métodos citados anteriormente. Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 3x2x5, caracterizado por três dietas, dois métodos de abate e cinco tempos de análises dos filés. Foram realizadas análises de desempenho e corporais, e de composição centesimal, oxidação lipídica pela formação de substâncias reativas ao ácido tiobarbitúrico (SRATB), e sensorial pelo método do Índice de Qualidade (MIQ) nos filés, nos tempos zero (antes do congelamento), 45, 90, 120 e 150 dias de estocagem. A suplementação da vitamina E não afetou os parâmetros de desempenho, entretanto influenciou na composição centesimal e na oxidação lipídica, protegendo os filés ao longo do período de estocagem. Foi elaborada tabela de avaliação dos filés congelados, pelo MIQ, instrumento útil para a análise de atributos de qualidade. / The aim of this investigation was to evaluate the influence of vitamin E dietary supplementation, and fish slaughtering methods (immersion in ice-water and exsanguination), on the fillets quality of tilapia, during frozen storage. Fish of 340 g mean initial body weight were fed for nine weeks with three isoenergetic (containing 3264,09 kcal DE/kg) and isonitrogenous (24,8% DP) diets. Two diets were supplemented with 100 mg/kg diet of α-tocopherol (TO group) and 100 mg of active source/kg diet of α-tocopheryl acetate (AC group), plus a nonsupplemented diet (control group – CO). At the termination of the 9-week feeding trial, fish were slaughtered by the summoned methods.A completely randomized design was used, in a 3x2x5 factorial scheme, characterized by the 3 vitamin E supplementation diets, 2 slaughter methods and 5 fillets analysis. The growth performance parameters, hepatosomatic and fat viscerosomatic index, centesimal composition, lipid oxidation determined by the thiobarbituric acid reactive substances (TBARS) and sensorial by Quality Index Method (QIM) analysis were analyzed in five times: before frozen storage, 45, 90, 120 and 150 days storage. The vitamin E supplementation did not influence the growth performance parameters, but centesimal composition were influenced, and vitamin E protected fillets from lipid oxidation in frozen storage. Fillets quality availability table were organized, by QIM, for to help in sensorial analysis.
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Influência da adição in vivo de vitamina E e de métodos de abate nos atributos de qualidade de filés de tilápia /Otani, Fabrizia Sayuri. January 2009 (has links)
Resumo: Este trabalho objetivou avaliar a influência da vitamina E pela suplementação por meio da dieta, em peixes submetidos a dois métodos de abate (imersão em água gelada e sangria), nos atributos de qualidade de filés congelados de tilápia (Oreochromis spp.). Peixes, com peso médio inicial de 340 g, foram alimentados por um período de nove semanas com três dietas isocalóricas (3264,09 kcal ED/kg) e isoprotéicas (24,8% PD), diferindo na adição de 100 mg/kg de ração de α-tocoferol (grupo TO), 100 mg de princípio ativo/kg de ração de acetato de α- tocoferil (grupo AC), e sem adição de vitamina E (grupo controle - CO). Ao final do período de alimentação, os peixes foram abatidos pelos métodos citados anteriormente. Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 3x2x5, caracterizado por três dietas, dois métodos de abate e cinco tempos de análises dos filés. Foram realizadas análises de desempenho e corporais, e de composição centesimal, oxidação lipídica pela formação de substâncias reativas ao ácido tiobarbitúrico (SRATB), e sensorial pelo método do Índice de Qualidade (MIQ) nos filés, nos tempos zero (antes do congelamento), 45, 90, 120 e 150 dias de estocagem. A suplementação da vitamina E não afetou os parâmetros de desempenho, entretanto influenciou na composição centesimal e na oxidação lipídica, protegendo os filés ao longo do período de estocagem. Foi elaborada tabela de avaliação dos filés congelados, pelo MIQ, instrumento útil para a análise de atributos de qualidade. / Abstract: The aim of this investigation was to evaluate the influence of vitamin E dietary supplementation, and fish slaughtering methods (immersion in ice-water and exsanguination), on the fillets quality of tilapia, during frozen storage. Fish of 340 g mean initial body weight were fed for nine weeks with three isoenergetic (containing 3264,09 kcal DE/kg) and isonitrogenous (24,8% DP) diets. Two diets were supplemented with 100 mg/kg diet of α-tocopherol (TO group) and 100 mg of active source/kg diet of α-tocopheryl acetate (AC group), plus a nonsupplemented diet (control group - CO). At the termination of the 9-week feeding trial, fish were slaughtered by the summoned methods.A completely randomized design was used, in a 3x2x5 factorial scheme, characterized by the 3 vitamin E supplementation diets, 2 slaughter methods and 5 fillets analysis. The growth performance parameters, hepatosomatic and fat viscerosomatic index, centesimal composition, lipid oxidation determined by the thiobarbituric acid reactive substances (TBARS) and sensorial by Quality Index Method (QIM) analysis were analyzed in five times: before frozen storage, 45, 90, 120 and 150 days storage. The vitamin E supplementation did not influence the growth performance parameters, but centesimal composition were influenced, and vitamin E protected fillets from lipid oxidation in frozen storage. Fillets quality availability table were organized, by QIM, for to help in sensorial analysis. / Orientadora: Léa Silvia Sant'Ana / Coorientador: João Batista Kochenborger Fernandes / Banca: Cristiane Rodrigues Pinheiro Neiva / Banca: Cláudio Angelo Agostinho / Mestre
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Farmakologické a metabolické ovlivnění funkce jaterních mitochondrií / Pharmacological and metabolic influence on liver mitochondrial functionsSobotka, Ondřej January 2017 (has links)
Liver mitochondria play a crucial role in intermediary metabolism and main metabolic pathways. We evaluated the pharmacological effect on liver mitochondria in vitro using two novel anticancer drugs: 3-bromopyruvate and α-tocopheryl succinate. Metabolic influence on liver mitochondria was performed in vivo by high fat and high cholesterol diet. Toxicity of both drugs was evaluated in cell cultures of hepatocytes isolated from rat and mouse liver. The effect of anticancer drugs on liver mitochondrial functions in vitro was studied on suspensions of isolated liver mitochondria, tissue homogenate and permeabilized hepatocytes. Mitochondrial respiration was measured using high-resolution respirometry. 3-bromopyruvate caused morphological and functional damage of primary rat and mouse hepatocytes in cell cultures; this toxic effect was accompanied by an increase of reactive oxygen species production and mitochondrial dysfunction. 3-bromopyruvate decreased the oxygen consumption of mitochondria energized by substrates for complex I and complex II. α-Tocopheryl succinate caused a decrease of succinate-dependent respiration in all experimental models both in coupled and in uncoupled states. The most pronounced effect of α-tocopheryl succinate was apparent in isolated mitochondria and the least pronounced...
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Cell Toxicity and Uptake of RRR-Alpha-Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS) by Various Cell ines <em>In Vitro</em>.Komguem Kamga, Christelle 16 August 2005 (has links) (PDF)
This research focused on investigating and comparing the cytotoxicity and cellular uptake of RRR-alpha-tocopheryl polyethylene glycol succinate (TPGS, with that of alpha-tocopheryl succinate (α-TS). Both TPGS and α-TS are water-soluble forms of vitamin E with important clinical applications. Cytotoxicity assays with RAW 264.7 and LNCaP cells incubated overnight with TPGS or α-TS at concentrations ≥ 12.4 μM suggest that α-TS is more cytotoxic than TPGS. Macrophages were found to be more sensitive than LNCaP cells when treated with similar concentrations of α-TS. For both cell lines, most of the TPGS or α-TS taken up remained esterified after 24 hours. Our results suggest that cell death was due to TPGS and/or α-TS and not alpha-tocopherol. A para-hydroxyanilide of α-TS (p-HATS) that could be used to distinguish between cellular TPGS and α-TS was studied. It was found that p-HATS can be detected electrochemically and that it is hydrolyzed to α-TOH.
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The Role of Liposomal Hybrids and Gold Nanoparticles in the Efficacious Transport of Nucleic Acids and Small Molecular Drugs for Cancer NanomedicineKumar, Krishan January 2015 (has links) (PDF)
The thesis entitled “The Role of Liposomal Hybrids and Gold Nanoparticles in the Efficacious Transport of Nucleic Acids and Small Molecular Drugs for Cancer Nanomedicine” elucidates the preparation of various liposomal formulations of cationic monomeric and gemini lipids where hydrophobic domains were consisted of tocopherol, cholesterol and pseudoglyceryl backbone for the cellular transport of nucleic acids. The thesis continues while elucidating the role of various pH sensitive molecules and gold nanoparticles in liposomes to improve the delivery efficacy levels. This thesis also elucidates the role of gold nanoparticles stabilized with natural pH sensitive molecules for efficacious drug delivery applications. Additionally, the role of such pH sensitive gold nanoparticles in association with liposomes for the co-delivery of drug and gene has been discussed. The work has been divided into six chapters.
Chapter 1A: Dimeric Lipids Derived from α-Tocopherol as Efficient Gene Transfection Agents. Mechanistic Insights into Lipoplex Internalization and Therapeutic Induction of Apoptotic Activity
In this chapter, we present cationic dimeric (gemini) lipids for significant plasmid DNA (pDNA) delivery to different cell lines without any marked toxicity in the presence of serum. The six gemini lipids possess α-tocopherol as their hydrophobic backbone and differ from each other in terms of their spacer chain lengths. Each of these gemini lipids mixed with a helper lipid 1, 2-dioleoyl phosphatidyl ethanolamine (DOPE), was capable of forming stable aqueous suspensions. These co-liposomal systems were examined for their potential to transfect pEGFP-C3 plasmid DNA in to nine cell lines of different origins. The transfection efficacies noticed in terms of EGFP expression levels using flow cytometry were well corroborated using independent fluorescence microscopy studies. Significant EGFP expression levels were reported using the gemini co-liposomes which counted significantly better than one well known commercial formulation lipofectamine 2000 (L2K). Transfection efficacies were also analyzed in terms of the degree of intracellular delivery of labeled plasmid DNA
(pDNA) using confocal microscopy which revealed an efficient internalization in the presence of serum. The cell viability assays performed using optimized formulations demonstrated no significant toxicity towards any of the cell lines used in the study. We also had a look at the lipoplex internalization pathway to profile the uptake characteristics. A caveolae/lipid raft route was attributed to their excellent gene transfection capabilities. The study was further advanced by using a therapeutic p53-EGFP-C3 plasmid and the apoptotic activity was observed using FACS and growth inhibition assay.
Figure 1. The co-liposomes of tocopheryl gemini lipids and DOPE for efficient delivery of p53-EGFP-C3 plasmid DNA that induces significant apoptotic response.
Chapter 1B: Efficacious Gene Silencing in Serum and Significant Apoptotic Activity Induction by Survivin Downregulation Mediated by Cationic Gemini Tocopheryl Lipids
Non-viral gene delivery offers cationic liposomes as promising instruments for the delivery of double-stranded RNA (ds RNA) molecules for successful sequence-specific gene silencing (RNA interference). The efficient delivery of siRNA (small interfering RNA) to cells while avoiding the unexpected side effects is an important prerequisite for the exploitation of the power of this excellent tool. We discuss in this chapter about six tocopherol based cationic gemini lipids, which induce substantial gene knockdown without any obvious cytotoxicity. All the efficient co-liposomal formulations derived from each of these geminis and a helper lipid, dioleoyl phosphatidyl ethanolamine (DOPE) were well characterized using physical methods such as atomic force microscopy (AFM) and dynamic light scattering (DLS). Zeta potential measurements were conducted to estimate the surface charge of these formulations. Flow cytometric analysis showed that the optimized co-liposomal formulations could transfect anti-GFP siRNA efficiently in three different GFP expressing cell lines, viz. HEK 293T, HeLa and Caco-2 significantly better than a potent commercial standard Lipofectamine 2000 (L2K) both in the absence and presence of serum (FBS). Notably, the knockdown activity of co-liposomes of gemini lipids was not affected even in the presence of serum (10% and 50% FBS) while it dropped down for L2K significantly. Observations under a fluorescence microscope, RT-PCR and western blot analysis substantiated the flow cytometry results. The efficient cellular entry of labeled siRNA in GFP expressing cells as evidenced from confocal microscopy put forward these gemini lipids among the potent lipidic carriers for siRNA. The efficient transfection capabilities were also profiled in a more relevant fashion while performing siRNA transfections against survivin (an anti-apoptotic protein) which induced substantial apoptosis. Furthermore, the survivin downregulation improved the therapeutic efficacy levels of an anticancer drug, doxorubicin significantly. In short, the new tocopherol based gemini lipids appear to be highly promising for achieving siRNA mediated gene knockdown in various cell lines.
Figure 2. The co-liposomes of tocopheryl gemini lipids and DOPE for efficient delivery of siRNA against survivin that induces significant apoptotic response.
Chapter 2: Efficacious in Vitro EGFP Expression and Silencing in Serum by Cationic Pseudoglyceryl Gemini Lipids
To elicit the desirable efficacy levels in cationic liposome mediated nucleic acid therapeutics has been part of extensive scientific efforts. This chapter describes three cationic gemini lipids and application of their co-liposomes with DOPE as potent pDNA (plasmid DNA) and siRNA (small interfering RNA) cytofectins for remarkably advanced efficacy levels in numerous cell lines in the presence of serum. The hydrophobic structural lineament of cationic gemini lipids is made up of pseudoglyceryl backbone linked to the hydrocarbon chains via oligo-oxyethylene units. The stable aqueous co-liposomal suspensions of gemini lipids showed an efficient binding to pDNA or siRNA and their significant intracellular delivery in various cell lines. The transfection capabilities of different co-liposomal formulations were profiled based on EGFP expression (pEGFP-C3 pDNA transfection) and EGFP knockdown (anti-GFP siRNA transfections) in EGFP expressing cell lines. The cellular EGFP expression levels and intracellular delivery of labeled nucleic acids were thoroughly studied using flow cytometry (FACS), fluorescence and confocal microscopy. The MTT based cell viability assay revealed no loss in cell viabilities for all of the transfection optimized lipoplexes of siRNA or pDNA. The transfection profile of gemini co-liposomes was noted to be significantly much better than a commercial lipofection reagent, Lipofectamine 2000 used for pDNA and siRNA applications in each of the cell lines studied. The co-liposomes and their transfection optimized lipoplexes were physiochemically characterized extensively by means of zeta potential, dynamic light scattering (DLS) and atomic force microscopy (AFM). In brief, these new gemini co-liposomal formulations seem to offer a great opportunity for successful nucleic acid (DNA and siRNA) delivery in a practical scenario.
Figure 3. Efficacious EGFP expression (pDNA transfection) and EGFP silencing (anti GFP siRNA transfection) mediated by co-liposomes of pseudoglyceryl gemini lipids and DOPE.
Chapter 3: Efficient Elicitation of Liposomal Nucleic acid delivery through the Eminence of Gold Nanoparticles Stabilized with pH Responsive Short Tripeptide Derived from Tyrosine Kinase NGF Receptors
The prerequisite in the area of gene therapy today is to serve transfection efficient formulations nullifying the enduring key issues. To this end, we discuss in this chapter, the role of hybrid liposomal formulations derived from structurally distinct cationic lipids, a neutral lipid (DOPE) and pH responsive short tripeptide (KFG, Lys-Phe-Gly) capped gold nanoparticles (PAuNPs). The hybrid liposomes are presented to be efficient enough to transfect pDNA leading to remarkably high gene expression levels in various cell lines of different origins in the presence of serum (FBS). Hybrid liposomes could deliver pDNA more effectively than the native liposomes and commercial standard lipofectamine 2000 (L2K) across the entire range of N/P ratios studied under the influence of intracellular pH response and gold nanoparticles prominence. The gene transfection capabilities are profiled based on transfections performed using two different plasmids (pGL3, luciferase activity and p-EGFP-C3, green fluorescent protein expression). pDNA cellular internalization and subsequent gene expression levels are studied using flow cytometry, fluorescence microscopy and confocal microscopic
studies. The extensive physiochemical characterization of hybrid liposomal formulation and their complexes with pDNA in comparison with respective native liposomes was performed using AFM, TEM, Zeta, DLS, gel retardation assay, U.V. and fluorescence emission measurements. The hybrid liposomes are shown to possess significantly higher fusion activity at lowered pH of intracellular compartments. These hybrid liposomes are fairly biocompatible across the concentration range used in transfection experiments. Precisely, introduction of these pH responsive tripeptide capped gold nanoparticles in to liposomal formulations straightforwardly must be more advantageous for a practical application in biomedical scenario to achieve therapeutic levels.
Figure 4. The hybrid of liposomes and tri-peptide capped gold nanoparticles for significantly improved gene expression levels.
Chapter 4: RNA Aptamer Decorated pH Sensitive Liposomes for Active Transport of Nucleic Acids in Specific Cancer Cells
This chapter describes the target specific transport of pH sensitive liposomes loaded with a RNA aptamer for promising nucleic acid therapeutics. The pH sensitive liposomes are constructed from a cationic cholesteryl gemini lipid (CGL), neutral helper lipid (DOPE) and gemini analog of a pH sensitive lipid, palmitoyl homocysteine (GPHC). The liposomes are shown to be significantly fusogenic that deliver the cargoes upon lowerin the pH (6.0). The fusogenic behaviour of the liposomes was thoroughly studied by means of dynamic light scattering (DLS), zeta potential, lipid mixing, calcein dequenching and atomic force microscopy (AFM). The facile integration of cholesterol
conjugated RNA aptamer in liposomes derived from cholesteryl gemini lipids was exploited for their delivery to specific cancer cells. The RNA aptamer specifically binds to epithelial cell adhesion molecule (EpCAM) with high affinity which is a cell surface marker in various solid cancers such as colorectal and breast carcinoma. These aptamer decorated pH sensitive liposomes could efficiently enter the EpCAM expressing COLO-205, Caco-2, MCF-7 and MDA-MB-231 cell lines while no such noticeable liposome transport was observed in EpCAM negative HEK 293T cells as evidenced by flow cytometry and confocal microscopy. Additionally, the liposomes are shown to be actively transported inside the cells, i.e., receptor mediated endocytosis. These liposomes could complex the nucleic acids (pDNA) in an efficient manner. The MTT based cell viability assay accounted no noticeable loss in cell viabilities for liposome treatments. Concisely, we have formulated RNA aptamer loaded pH sensitive liposomes that would certainly be promising tool in target based cancer nanomedicine.
Figure 5. (A) Cellular internalization of DY-647 labeled aptamer loaded pH sensitive liposomes. (B) The liposomes were actively internalized through receptor mediated endocytosis. Each panel (A and B) represents (from left to right) bright field image, aptamer fluorescence, DAPI stained nuclei and merge of previous three impressions.
Chapter 5: Natural Tri-peptide Capped Gold Nanoparticles for Efficacious Doxorubicin Delivery in Vitro and in Vivo
Nanotechnology has gained ever increasing interest for the successful implementation of chemotherapy based treatment of cancer. This chapter describes the role of gold nanoparticles (AuNPs) capped with a natural pH responsive short tri-peptide (Lys-Phe–Gly or KFG) for significant intracellular delivery of an anti-cancer drug, doxorubicin (DOX). A significantly increased apoptotic response was noted for DOX treatments mediated by KFG-AuNPs in comparison with drug alone treatments in various cell lines (BT-474, HeLa, HEK 293T and U251) in vitro. Furthermore, KFG-AuNPs mediated DOX treatment significantly decreased cell proliferation and tumor growth in BT-474 cell xenograft model in nude mice. In addition, KFG-AuNPs showed efficacious drug delivery in DOX-resistant HeLa cells (HeLa-DOXR) in comparison with drug alone treatments.
Figure 6. Representative images of excised tumors after doxorubicin treatment mediated by pH responsive tri-peptide capped gold nanoparticles (DOX-KFG-AuNPs) (C) in comparison with doxorubicin alone treatments (B) and untreated tumors (A). Extensive cell death as observed under Hematoxylin/eosin (H&E) (D) and TUNEL (E) staining of DOX-KFG-AuNPs treated tumor sections.
Chapter 6: Significant Apoptotic Activity Induction by Efficacious Co-delivery of p53 Gene and Doxorubicin Mediated by the Combination of Co-liposomes of Cationic Gemini lipid and pH Responsive Tri-peptide
Combining chemotherapy with gene therapy has appeared as an efficient tool to treat complex biological disorder like cancer. Herein, we show efficient co-delivery of DNA
and an anti-cancer drug, doxorubicin (DOX) by means of gemini cationic liposome (GCL) based lipoplex nanoaggregates that are coated with DOX encapsulated pH responsive tripeptide nanovesicles. The lipoplex, tripeptide vesicles and their association was thoroughly studied using dynamic light scattering (DLS), zeta potential, atomic force microscopy (AFM). Flow cytometry, fluorescence and confocal microscopic analysis revealed that the GCL-tripeptide association could significantly co-deliver the p53 expression plasmid (p53-EGFP-C3) and DOX in HeLa and HEK 293T cells in the presence of serum. A synergistic increase in gene expression level and DOX internalization was observed in co-delivery which was even substantially higher than individual lipoplex transfection and DOX treatment. The apoptosis induced due to p53 expression and DOX was profiled with the help of annexin-V positivity analysis under flow cytometry and nuclear damage analysis by DAPI nuclei counterstaining under confocal microscopy which noted to be significantly higher in cells during co-delivery. The MTT based cell viability assay revealed a significantly increased loss in cell viability counts for co-delivery treatments. Such a system delivering synergistically increased significant efficacy levels in combinatorial drug and nucleic acid therapeutics would be certainly advantageous for practical biomedical applications.
Figure 7. The co-delivery of pDNA and drug (doxorubicin) mediated by GCL-tripeptide association as observed under (A) confocal microscopy (pDNA; green and doxorubicin; red) and (B) flow cytometry.
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