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1.
Pharmaceutics ; 15(10)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37896139

RESUMO

The cottontail rabbit papillomavirus (CRPV)-associated VX2 carcinoma of the New Zealand White rabbit serves as a model system for human papillomavirus (HPV)-associated head and neck squamous cell carcinomas (HNSCCs). The aim of this study was to evaluate the tumor-inhibiting effect of RNAi-mediated knockdown of the CRPV oncogenes, E6 and E7, using siRNA-loaded lipopolyplexes (LPPs). VX2-carcinoma-derived cells were cultured for up to 150 passages. In addition, CRPV E6 and E7 oncogenes were transiently expressed in COS-7 cells. Efficiency and safety of LPPs were evaluated in both VX2 cells and the COS-7 cell line. Both of these in vitro CRPV systems were validated and characterized by fluorescence microscopy, Western blot, and RT-qPCR. Efficient knockdown of CRPV E6 and E7 was achieved in VX2 cells and COS-7 cells pretransfected with CRPV E6 and E7 expression vectors. Knockdown of CRPV oncogenes in VX2 cells resulted in reduced viability, migration, and proliferation and led to a G0/G1 block in the cell cycle. CRPV E6 and E7 siRNA-loaded LPPs could represent promising therapeutic agents serving as a paradigm for the treatment of papillomavirus-positive cancers and could be of value for the treatment of CRPV-associated diseases in the rabbit such as papillomas and cancers of the skin.

2.
Drug Deliv ; 29(1): 2072-2085, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35848469

RESUMO

Hypoxia, an oxygen-deprived condition of the tumor, is one of the major reasons for resistance to chemotherapy. Carbonic anhydrases are generally involved in pH homeostasis in normal conditions, but in solid tumors having a strong relation with hypoxia, the carbonic anhydrase IX (CA-IX) enzyme is overexpressed and results in an extracellular acidic environment. For most weakly basic anticancer drugs, including doxorubicin (Dox), the ionization in an acidic environment limits their cellular uptake, and consequently, the tumor exposure to the drug at sub-therapeutic concentration comes out as chemoresistance. Herein, a combined drug delivery system of liposomes and mesoporous silica nanoparticles (MSNPs) was developed for the co-delivery of the CA-IX enzyme inhibitor and Dox in hypoxic condition. The unique structure of MSNPs with higher surface area was utilized for higher drug loading and sustained release of Dox. Additionally, the biocompatible nature of liposomal coating as a second loading site for the CA-IX enzyme inhibitor has provided gatekeeping effects at pore opening to avoid premature drug release. Lipid coated MSNPs as a co-delivery system for Dox and the CA-IX inhibitor have synergistic cytotoxic effects against MDA-MB 231 breast cancer cells in hypoxic conditions. These findings assure the potential of this drug delivery system to overcome hypoxia-related chemoresistance.


Assuntos
Antineoplásicos , Neoplasias , Anidrase Carbônica IX , Inibidores da Anidrase Carbônica/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Humanos , Hipóxia/tratamento farmacológico , Neoplasias/tratamento farmacológico
3.
Cancers (Basel) ; 13(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34885213

RESUMO

Recent advances in molecular biology have discovered the mysterious role of long non-coding RNAs (lncRNAs) as potential biomarkers for cancer diagnosis and targets for advanced cancer therapy. Studies have shown that lncRNAs take part in the incidence and development of cancers in humans. However, previously they were considered as mere RNA noise or transcription byproducts lacking any biological function. In this article, we present a summary of the progress on ascertaining the biological functions of five lncRNAs (HOTAIR, NEAT1, H19, MALAT1, and MEG3) in female-oriented cancers, including breast and gynecological cancers, with the perspective of carcinogenesis, cancer proliferation, and metastasis. We provide the current state of knowledge from the past five years of the literature to discuss the clinical importance of such lncRNAs as therapeutic targets or early diagnostic biomarkers. We reviewed the consequences, either oncogenic or tumor-suppressing features, of their aberrant expression in female-oriented cancers. We tried to explain the established mechanism by which they regulate cancer proliferation and metastasis by competing with miRNAs and other mechanisms involved via regulating genes and signaling pathways. In addition, we revealed the association between stated lncRNAs and chemo-resistance or radio-resistance and their potential clinical applications and future perspectives.

4.
Pharmaceutics ; 13(9)2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34575472

RESUMO

The immediate release of chemotherapeutics at the target site, along with no premature release in circulation is always challenging. The purpose of this study was to develop a stimuli responsive drug delivery system, composed of lipid supported mesoporous silica nanoparticles (MSNPs) for triggered drug release at the target site and simultaneously avoiding the premature release. MSNPs with a higher drug loading capacity and very slow release were designed so as to enhance release by FDA approved US-irradiation. Doxorubicin, as a model drug, and perfluoropentane (PFP) as a US responsive material, were entrapped in the porous structure of MSNPs. Lipid coating enhanced the cellular uptake and in addition provided a gatekeeping effect at the pore opening to reduce premature release. The mechanical and thermal effects of US induced the conversion of liquid PFP to a gaseous form that was able to rupture the lipid layer, resulting in triggered drug release. The prolonged stability profile and non-toxic behavior made them suitable candidate for the delivery of anticancer drugs. This smart system, with the abilities of better cellular uptake and higher cytotoxic effects on US-irradiation, would be a good addition to the applied side of chemotherapeutic advanced drug delivery systems.

5.
Mater Sci Eng C Mater Biol Appl ; 129: 112420, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34579929

RESUMO

Zein is an FDA-approved maize protein featured by its manipulative surface and the possibility of fabrication into nanomaterials. Although extensive research has been carried out in zein-based technology, limited work is available for the application of zein in the field of cancer photodynamic therapy (PDT). In this work, we report zein as a carrier for the natural photosensitizer hypericin in the PDT of hepatocellular carcinoma in vitro. Zein was modified through chemical PEGylation to form PEGylated zein micelles that were compared with two zein nanoparticle formulations physically stabilized by either the lecithin/pluronic mixture or sodium caseinate. FT-IR, 1HNMR and HP-SEC MALS approaches were employed to confirm the chemical PEGylation of zein. Our developed zein nanoparticles and micelles were further characterized by photon correlation spectroscopy (PCS) and atomic force microscopy (AFM). The obtained results showed relatively smaller sizes and higher encapsulation of hypericin in the micellar zein than the nanoparticle-based formulations. Phototoxicity on hepatocellular carcinoma (HepG2 cells) manifested a dose-dependent toxicity pattern of all designed zein formulations. However, superior cytotoxicity was prominent for the hypericin-based micelles, which was influenced by the higher cellular uptake profile. Consequently, the treated HepG2 cells manifested a higher level of intracellular generated ROS and disruption of mitochondrial membrane potential, which induced apoptotic cell death. Comparatively, the designed hypericin formulations indicated lower phototoxicity profile in murine fibroblast L929 cells reflecting their safety on normal cells. Our investigations suggested that the surface-modified zein could be employed to enhance the delivery of the hydrophobic hypericin in PDT and pave the way for future in vivo and clinical applications in cancer treatment.


Assuntos
Neoplasias Hepáticas , Perileno , Fotoquimioterapia , Zeína , Animais , Antracenos , Camundongos , Perileno/análogos & derivados , Perileno/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Eur J Pharm Biopharm ; 165: 31-40, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33962002

RESUMO

The exposure of cancer cells to subtherapeutic drug concentrations results in multidrug resistance (MDR). The uniqueness of mesoporous silica nanoparticles (MSNPs) with larger surface area for higher drug loading can solve the issue by delivering higher amounts of chemotherapeutics to the cancer cells. However, premature drug release and lower biocompatibility remain challenging. Lipid coating of MSNPs at the same time, can enhance the stability and biocompatibility of nanocarriers. Furthermore, the lipid coating can reduce the systemic drug release and deliver higher amounts to the tumor site. Herein, lipid coated MSNPs were prepared by utilizing cationic liposomes and further investigations were made. Our studies have shown the higher entrapment of doxorubicin (Dox) to MSNPs due to availability of porous structure. Lipid coating could provide a barrier to sustain the release of drug along with reduced premature leakage. In addition, the biocompatibility and enhanced interaction of cationic liposomes to cell membranes resulted in better cellular uptake. Lipid coated silica nanoparticles have shown higher cellular toxicity as compared to non-lipid coated particles. The increase in cytotoxicity with time supports the hypothesis of sustained release of drug from lipid coated MSNPs. We propose the Lip-Dox-MSNPs as an effective approach to treat cancer by delivering and maintaining effective concentration of drugs to the tumor site without systemic side effects.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Neoplasias/tratamento farmacológico , Antibióticos Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipossomos , Nanopartículas/química , Neoplasias/patologia , Tamanho da Partícula , Porosidade , Dióxido de Silício/química , Propriedades de Superfície
7.
Int J Nanomedicine ; 16: 951-976, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33603362

RESUMO

PURPOSE: Lipoparticles are the core-shell type lipid-polymer hybrid systems comprising polymeric nanoparticle core enveloped by single or multiple pegylated lipid layers (shell), thereby melding the biomimetic properties of long-circulating vesicles as well as the mechanical advantages of the nanoparticles. The present study was aimed at the development of such an integrated system, combining the photodynamic and chemotherapeutic approaches for the treatment of multidrug-resistant cancers. METHODS: For this rationale, two different sized Pirarubicin (THP) loaded poly lactic-co-glycolic acid (PLGA) nanoparticles were prepared by emulsion solvent evaporation technique, whereas liposomes containing Temoporfin (mTHPC) were prepared by lipid film hydration method. Physicochemical and morphological characterizations were done using dynamic light scattering, laser doppler anemometry, atomic force microscopy, and transmission electron microscopy. The quantitative assessment of cell damage was determined using MTT and reactive oxygen species (ROS) assay. The biocompatibility of the nanoformulations was evaluated with serum stability testing, haemocompatibility as well as acute in vivo toxicity using female albino (BALB/c) mice. RESULTS AND CONCLUSION: The mean hydrodynamic diameter of the formulations was found between 108.80 ± 2.10 to 405.70 ± 10.00 nm with the zeta (ζ) potential ranging from -12.70 ± 1.20 to 5.90 ± 1.10 mV. Based on the physicochemical evaluations, the selected THP nanoparticles were coated with mTHPC liposomes to produce lipid-coated nanoparticles (LCNPs). A significant (p< 0.001) cytotoxicity synergism was evident in LCNPs when irradiated at 652 nm, using an LED device. No incidence of genotoxicity was observed as seen with the comet assay. The LCNPs decreased the generalized in vivo toxicity as compared to the free drugs and was evident from the serum biochemical profile, visceral body index, liver function tests as well as renal function tests. The histopathological examinations of the vital organs revealed no significant evidence of toxicity suggesting the safety and efficacy of our lipid-polymer hybrid system.


Assuntos
Lipídeos/química , Nanopartículas/química , Neoplasias Ovarianas/tratamento farmacológico , Fotoquimioterapia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração Inibidora 50 , Cinética , Lipossomos , Testes de Função Hepática , Mesoporfirinas/farmacologia , Mesoporfirinas/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Neoplasias Ovarianas/patologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade Aguda
8.
Eur J Pharm Biopharm ; 158: 390-400, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33338603

RESUMO

Metastatic breast cancer is one of the most common causes of cancer-related death in women worldwide. The transmembrane metalloprotease-disintegrin (ADAM8) protein is highly overexpressed in triple-negative breast cancer (TNBC) cells and potentiates tumor cell invasion and extracellular matrix remodeling. Exploiting the high expression levels of ADAM8 in TNBC cells by delivering anti-ADAM8 antibodies efficiently to the targeted site can be a promising strategy for therapy of TNBC. For instance, a targeted approach with the aid of ultra-high field magnetic resonance imaging (UHF-MRI) activatable thermosensitive liposomes (LipTS-GD) could specifically increase the intracellular accumulation of cytotoxic drugs. The surface of doxorubicin-loaded LipTS-GD was modified by covalent coupling of MAB1031 antibody (LipTS-GD-MAB) in order to target the overexpressed ADAM8 in ADAM8 positive MDA-MB-231 cells. Physicochemical characterization of these liposomes was performed using size, surface morphology and UHF-MRI imaging analysis. In vitro cell targeting was investigated by the washing and circulation method. Intracellular trafficking and lysosomal colocalization were assessed by fluorescence microscopy. Cell viability, biocompatibility and in-ovo CAM assays were performed to determine the effectiveness and safety profiles of liposome formulations. Our results show specific binding and induction of doxorubicin release after LipTS-GD-MAB treatment caused a higher cytotoxic effect at the cellular target site.


Assuntos
Proteínas ADAM/metabolismo , Antibióticos Antineoplásicos/administração & dosagem , Anticorpos Monoclonais/farmacologia , Imagem por Ressonância Magnética Intervencionista , Proteínas de Membrana/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacocinética , Disponibilidade Biológica , Mama/diagnóstico por imagem , Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Embrião de Galinha , Membrana Corioalantoide , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Lipossomos , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/patologia
9.
Sci Rep ; 10(1): 21446, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33293580

RESUMO

Clinical success of effective gene therapy is mainly hampered by the insufficiency of safe and efficient internalization of a transgene to the targeted cellular site. Therefore, the development of a safe and efficient nanocarrier system is one of the fundamental challenges to transfer the therapeutic genes to the diseased cells. Polyamidoamine (PAMAM) dendrimer has been used as an efficient non-viral gene vector (dendriplexes) but the toxicity and unusual biodistribution induced by the terminal amino groups (-NH2) limit its in vivo applications. Hence, a state of the art lipid modification with PAMAM based gene carrier (lipodendriplexes) was planned to investigate theirs in vitro (2D and 3D cell culture) and in vivo behaviour. In vitro pDNA transfection, lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) generation, cellular protein contents, live/dead staining and apoptosis were studied in 2D cell culture of HEK-293 cells while GFP transfection, 3D cell viability and live/dead staining of spheroids were performed in its 3D cell culture. Acute toxicity studies including organ to body index ratio, hematological parameters, serum biochemistry, histopathological profiles and in vivo transgene expression were assessed in female BALB/c mice. The results suggested that, in comparison to dendriplexes the lipodendriplexes exhibited significant improvement of pDNA transfection (p < 0.001) with lower LDH release (p < 0.01) and ROS generation (p < 0.05). A substantially higher cellular protein content (p < 0.01) and cell viability were also observed in 2D culture. A strong GFP expression with an improved cell viability profile (p < 0.05) was indicated in lipodendriplexes treated 3D spheroids. In vivo archives showed the superiority of lipid-modified nanocarrier system, depicted a significant increase in green fluorescent protein (GFP) expression in the lungs (p < 0.01), heart (p < 0.001), liver (p < 0.001) and kidneys (p < 0.001) with improved serum biochemistry and hematological profile as compared to unmodified dendriplexes. No tissue necrosis was evident in the animal groups treated with lipid-shielded molecules. Therefore, a non-covalent conjugation of lipids with PAMAM based carrier system could be considered as a promising approach for an efficient and biocompatible gene delivery system.


Assuntos
Técnicas de Cultura de Células/métodos , Proteínas de Fluorescência Verde/metabolismo , Lipídeos/química , Plasmídeos/genética , Poliaminas/farmacocinética , Animais , Sobrevivência Celular/efeitos dos fármacos , Feminino , Proteínas de Fluorescência Verde/genética , Células HEK293 , Humanos , Rim/metabolismo , L-Lactato Desidrogenase/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Miocárdio/metabolismo , Poliaminas/administração & dosagem , Poliaminas/química , Espécies Reativas de Oxigênio/metabolismo , Testes de Toxicidade Aguda , Transfecção
10.
Pharmaceuticals (Basel) ; 13(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142782

RESUMO

In this study, the potential cytotoxicity of four plant extracts originated from Cameroon: Xylopia aethiopica (XA), Imperata cylindrica (IC), Echinops giganteus (EG) and Dorstenia psilurus (DP) were examined in vitro. We tested the anti-proliferative activity of the methanolic extracts of these compounds using MTT assay on seven different human cancer cell lines: HeLa, MDA-MB-231, A549, HepG2, U-87, SK-OV-3 and HL60. Induction of cell death was assessed by cell cycle analysis, apoptosis was determined by Annexin V-FITC binding and caspase 3/7 activity. As well, changes in mitochondrial membrane potential (MMP) and cell migration were tested. The genetic toxicity, using the alkaline comet assay, was evaluated. The studied extracts inhibited the cell proliferation of all tested cancer cell lines with concentration dependent effect over time. All of these extracts mainly induced apoptosis of HeLa cells by the accumulation of hypodiploid cells in the sub-G0/G1 phase and increasing the activity of caspase 3/7, as well they showed potential MMP disturbance and expressed a marked inhibitory effect on cell migration. Assessment of probable genetic toxicity by these extracts revealed no or minimum incidence of genetic toxicity. Therefore, the studied plant extracts are exhibiting potent anticancer activity based upon marked induction of tumor-cell death.

11.
Cancers (Basel) ; 12(11)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167593

RESUMO

Photodynamic therapy (PDT) is a minimally invasive therapeutic approach used in the treatment of various medical conditions and cancerous diseases, involving light, a photosensitizing substance, and oxygen. Curcumin, a naturally occurring compound, carries antitumor activities and potentially could be exploited as a photosensitizer in PDT. Only little is known about liposomal-encapsulated curcumin that could help in increasing the efficacy, stability, and bioavailability of this compound. This study investigates the in vitro effects of curcumin-loaded liposomes in combination with PDT. Three papilloma virus-associated cell lines were treated with curcumin-loaded liposomes corresponding to a curcumin concentration of 0-100 µmol/L for 4 h followed by illumination at 457 nm (blue) for 45, 136, and 227 s at a fluence of 220.2 W/m2 (100 mA) corresponding to 1, 3 and 5 J·cm-2. After 24 h, the biological outcome of the treatment was assessed with the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), SYTO9/PI (propidium iodide), Annexin V-FITC (fluorescein isothiocyanate)/PI, clonogenic survival, and scratch (wound closure) assays. Photoactivation of curcumin-loaded liposomes led to a significant reduction in colony formation and migratory abilities, as well as to an increase in tumor cell death. The results point to the combination of curcumin-loaded liposomes with PDT as a potentially useful tool for the treatment of papillomavirus-associated malignancies.

12.
Int J Pharm ; 591: 119993, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33086089

RESUMO

P-glycoprotein (P-gp) associated multidrug resistance (MDR) represents a major failure in cancer treatment. The overexpression of P-gp is responsible for ATP-dependent efflux of drugs that decrease their intracellular accumulation. An effective downregulation of MDR1 gene using small interfering RNA (siRNA) is one of the safe and effective tools to overcome the P-gp triggered MDR. Therefore, the development of an efficient and non-toxic carrier system for siRNA delivery is a fundamental challenge for effective cancer treatment. Polyamidoamine (PAMAM) dendrimer has been used for efficient delivery of siRNA (dendriplexes) to the tumor cells but the associated toxicity problems render its use in biological applications. A non-covalent lipid modification (lipodendriplexes) is supposed to offer a promising strategy to overcome the demerits linked to the naked dendriplexes system. In the current study, we deliver siRNA, designed against MDR1 gene (si-MDR1), in colorectal carcinoma cells (Caco-2), having overexpression of P-gp, to check the role of MDR1 gene in tumor progression and multidrug resistance using two dimensional (2D) and three dimensional (3D) environment. Imatinib mesylate (IM), a P-gp substrate, was used as model drug. Our results revealed that the effective knockdown by lipodendriplexes system can significantly reduce the tumor cell migration in 2D (p < 0.001) and 3D (p < 0.001) cell cultures as compared to unmodified dendriplexes and si-Control groups. It was also observed that lipodendriplexes aided downregulation of MDR1 gene effectively, re-sensitized the Caco-2 cells for IM uptake and showed a significantly (p < 0.001) higher apoptosis. Our findings imply that our lipodendriplexes system has a great potential for siRNA delivery, however, further in vivo application using a suitable targeted system can play a major role for better cancer therapeutics.


Assuntos
Apoptose , Resistencia a Medicamentos Antineoplásicos , Células CACO-2 , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Inibidores de Proteínas Quinases , RNA Interferente Pequeno
13.
Macromol Biosci ; 20(12): e2000173, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32881380

RESUMO

This work focuses on the development of ultrasound contrast vesicles for ultrasound-mediated enhanced transfection of nucleic acids in the cancer cells and projects its application as a tool for diagnostic imaging. The ultrasound contrast vesicles are stable, anionic, nanoscaled vesicles with ultrasound contrast equivalent to the commercially available SonoVue. These anionic lipid vesicles establish electrostatic interaction with cationic polyplexes based on linear polyethylenimine (22kDa) forming lipopolyplexes with ultrasound contrast. The lipopolyplexes are characterized regarding shape, size, and zeta potential. When exposed to low frequency ultrasound, these carriers show elevated transfection efficiency and reduced cytotoxicity. The effect of post-transfection ultrasound on cellular uptake of lipopolyplexes is also evaluated. An analogous transfection is also observed in the tumor mimicking multicellular 3D spheroid culture of ovarian cancer cells. The emergence of tumor imaging and enhanced gene delivery by medical ultrasound, a noninvasive imaging modality, is considered paving the way for efficient theranostic gene therapy.


Assuntos
Meios de Contraste/farmacologia , Lipídeos/farmacologia , Neoplasias/diagnóstico por imagem , Ultrassonografia , Ânions/química , Ânions/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Meios de Contraste/química , Técnicas de Transferência de Genes/tendências , Humanos , Lipídeos/química , Lipossomos/química , Lipossomos/farmacologia , Esferoides Celulares/ultraestrutura
14.
Plant Dis ; 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32804040

RESUMO

Rice (Oryza sativa L.) is one of the highly consumed cereal grain crops in Pakistan. In September 2017, leaf samples of cultivar Basmati-385 showing brown to dark brown spots (5 to 9 mm in diameter) that were oval or cylindrical in shape with a chlorotic yellow halo and grayish tan centers were collected from fields near the University of Agriculture, Faisalabad (31.43633 N 73.05981 E). Average disease incidence was 69% in six rice fields that were sampled for diseased plants with visible symptoms. To isolate the pathogen, from 20 diseased leaves, 5 mm2 segments from the margins of lesions were cut, rinsed with sterile distilled water (SDW), surface disinfected by 70% ethanol and again rinsed with SDW. The samples were dried on sterilized filter paper discs, plated on potato dextrose agar (PDA) and incubated at 27°C for 5 to 7 days. Twelve isolates were sub-cultured and single-sporing was performed to obtain pure cultures. Fungal isolates with light to dark gray in color, thick or fluffy aerial mycelium, circular and smooth margins were obtained after 7 days of incubation. Conidia were 47-83 µm × 10-17 µm (n=100), with 4 to 10 distosepta, dark or olivaceous brown, straight or moderately curved, and the cells at the ends occasionally looked paler than those in the middle. Conidiophore of the fungus were simple, smooth, cylindrical, septate, and straight to flexuous. These characteristics resembled those of Bipolaris zeicola (Stout) Shoemaker (Manamgoda et al. 2014). For molecular identification, genomic DNA (isolate SU-11) was extracted and the internal transcribed spacer (ITS) region, large subunit (LSU) of ribosomal DNA, translation elongation factor (tef), glyceraldehyde 3-phosphate dehydrogenase (gpd), and RNA polymerase II second largest subunit (rpb2) genes were amplified and sequenced by using the primers ITS1-F/ITS4-R (White et al. 1990), LROR-F/LR5-R (Schoch et al. 2012), EF1-983F/EF1-2218R (Rehner and Buckley 2005), GPD1F/GPD2R (Berbee et al. 1999), and 5F2/7CR (O'Donnell et al. 2007), respectively. BLASTn searches showed 100% homology with the LSU and rpb2 sequences of B. zeicola (GenBank Accession Nos. MH876201 and HF934842) and 98-99% similarity with ITS, tef, and gpd sequences of B. zeicola (GenBank Accession Nos. KM230398, KM093752 and KM034815). The sequences of ITS, LSU, tef, gpd, and rpb2 were deposited in GenBank with accession numbers MN871712, MN877767, MN867685, MN904511 and MT349837, respectively. To fulfill Koch's postulates, 25 greenhouse-grown rice plants (cv. Basmati-385) at 2- to 3-leaf stage were spray inoculated with a spore suspension (105 spores/ml; isolate SU-11) prepared in SDW. Plants were covered with plastic wraps to maintain humid conditions for 24 hours and incubated at 27°C for one week. Similarly, ten non-inoculated plants sprayed with SDW served as controls. After one week, observed symptoms were similar to those from natural infections and no disease symptoms were observed on the non-inoculated plants. The experiment was repeated twice and the pathogen was re-isolated from the infected leaves and characterized morphologically. Globally, B. zeicola has also been reported to cause the leaf spot of rice and maize plants (Sivanesan 1987; Kang et al. 2018). To our information, this is the first report of B. zeicola causing brown leaf spot of rice in Pakistan. The increasing risk of this fungal pathogen in the rice-growing areas of Pakistan need a rigorous exploration and outreach effort to develop effective management practices.

15.
Eur J Pharm Biopharm ; 150: 50-65, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32151728

RESUMO

5,10,15,20-Tetrakis(3-hydroxyphenyl)chlorin (mTHPC; temoporfin) is one of the most potent second-generation photosensitizers available today for the treatment of a variety of clinical disorders and has a unique capability of being activated at different wavelengths. However, due to its highly lipophilic nature, poor solubility in the aqueous media and poor bioavailability limits its application in anticancer therapies. To overcome these potential issues, we developed three different liposomal formulations with mTHPC encapsulated in hydrophobic milieu thus increasing the bioavailability of the drug. The prepared formulations were characterized in terms of hydrodynamic diameter, surface charge, encapsulation efficiency, and stability studies. The mean size of the liposomes was found to be in the nanoscale range (about 100 nm) with zeta potential ranging from -6.0 to -13.7 mV. mTHPC loaded liposomes were also evaluated for morphology using atomic force microscopy (AFM) and cryo-transmission electron microscopy (cryo-TEM). Data obtained from the hemocompatibility experiments showed that these formulations were compatible with blood showing less than 10% hemolysis and coagulation time lower than 40 s. The results obtained from the single-cell gel electrophoresis assay also demonstrated no incidence of genotoxicity. Photodynamic destruction of SK-OV-3 cells using mTHPC loaded liposomes showed a dose-response relationship upon irradiation with two different wavelength lights (blue λ = 457 nm & red λ = 652 nm). A 10-fold pronounced effect was produced when liposomal formulations were irradiated at 652 nm as compared to 457 nm. This was also evaluated by the quantitative assessment of reactive oxygen production (ROS) using fluorescence microscopy. The qualitative assessment of PDT pre- and post-irradiation was visualized using confocal laser scanning microscopy (CLSM) which demonstrated an intense localization of mTHPC liposomes in the perinuclear region. Chick chorioallantoic membrane assay (CAM) was used as an alternative in-ovo model to demonstrate the localized destruction of tumor microvasculature. Overall, the prepared nanoformulation is a biocompatible, efficient and well characterized delivery system for mTHPC for the safe and effective PDT.


Assuntos
Carcinoma/tratamento farmacológico , Membrana Corioalantoide/irrigação sanguínea , Lipídeos/química , Mesoporfirinas/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Animais , Carcinoma/patologia , Linhagem Celular Tumoral , Embrião de Galinha , Relação Dose-Resposta a Droga , Composição de Medicamentos , Feminino , Humanos , Lipossomos , Mesoporfirinas/química , Densidade Microvascular/efeitos dos fármacos , Nanopartículas , Neoplasias Ovarianas/patologia , Fármacos Fotossensibilizantes/química , Solubilidade
16.
AAPS PharmSciTech ; 21(2): 60, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31912272

RESUMO

The formation of biofilm by Streptococcus mutans on the tooth surface is the primary cause of dental caries and periodontal diseases, and fluoride (F) has shown tremendous potential as a therapeutic moiety against these problems. Herein, we report an efficient multi-ingredient bioadhesive film-based delivery system for oral cavity to combat dental problems with an ease of administration. Thiolated chitosan-based bioadhesive film loaded with calcium fluoride nanoparticles (CaF2 NPs) and lignocaine as a continuous reservoir for prolonged delivery was successfully prepared and characterized. The polygonal CaF2 NPs with an average particle size less than 100 nm, PDI 0.253, and + 6.10 mV zeta potential were synthesized and loaded in film. The energy dispersive x-ray (EDX) spectroscopy confirmed the presence 33.13% F content in CaF2 NPs. The characterization of the three film trials for their mechanical strength, bioadhesion, drug release, and permeation enhancement suggested film B as better among the three trials and showed significant outcomes, indicating the potential application of the medicated bioadhesive film. In vitro dissolution studies revealed sustained release pattern of lignocaine and CaF2 NP following Krosmeyer-Peppas model over 8 h. Franz diffusion studies showed the prolonged contact time of film with mucosa that facilitated the transport of CaF2 NPs and lignocaine across the mucosa. Hence, the prepared bioadhesive film-based system showed good potential for better management of dental problems. Graphical Abstract.


Assuntos
Fluoreto de Cálcio/química , Lidocaína/química , Nanopartículas/química , Quitosana/química , Sistemas de Liberação de Medicamentos
17.
Int J Pharm ; 575: 118961, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31846731

RESUMO

Surface modification of nanoparticles with aptamer is gaining popularity lately due to its selective targeting and low immunogenicity. In this study, sorafenib tosylate (SFB) was loaded in biodegradable PLGA nanoparticles prepared by solvent evaporation method. The surfaces of drug deprived and drug-loaded particles (PN and PNS, respectively) were coupled with aptamer to target ErbB3 using EDC/NHS chemical modification. Nanoparticles were characterized with regard to their size, shape and chemical composition by dynamic light scattering, atomic force microscopy, FTIR and elemental analysis respectively. To evaluate the particles in vitro cell culture studies were performed. Cell viability assay, pathway analysis and apoptosis assay showed cellular toxicity in the presence of aptamer in PNS-Apt (p < 0.001). Metastatic progression assay showed decreased cell migration in the presence of aptamer and SFB. Confocal laser scanning microscopy was used to visualize the receptor-mediated time-dependent intracellular uptake and distribution of the nanoparticles throughout the cytoplasm. The findings of the current study demonstrated the potential efficacy of the surface modified SFB-loaded particles against ErbB3.


Assuntos
Aptâmeros de Nucleotídeos/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , Receptor ErbB-3/antagonistas & inibidores , Sorafenibe/farmacologia , Apoptose/efeitos dos fármacos , Aptâmeros de Nucleotídeos/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Sorafenibe/administração & dosagem , Tecnologia Farmacêutica/métodos
18.
Eur J Pharm Biopharm ; 145: 42-53, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31626948

RESUMO

The delivery of aptamer modified therapeutic moieties to specific tissue sites has become one of the major therapeutic choices to reduce the toxicity of inhibitory drugs. Bearing this in mind, the current study was designed using sorafenib (SFB) encapsulated microparticles (MP) prepared with biodegradable poly (D, L-lactic-co-glycolic acid) (PLGA) copolymer. The surfaces of these microparticles were modified with RNA aptamer having a binding affinity towards ErbB3 receptors. SFB-loaded MP (MPS) were prepared by o/w solvent evaporation method and the surface was coupled with the amino group of aptamer by EDC/NHS chemistry. Physiochemical investigations were done by dynamic light scattering, scanning electron microscopy and FTIR. In vitro apoptosis assay, cell viability assay and metastatic progression showed a significant decrease (p < 0.001) in vitro cell viability for MPS and MPS-Apt as compared to MP. The synergistic combination of SFB and aptamer also decreased the metastatic progression of cells for an extended period. Microparticles were also evaluated for in vivo toxicity in female BALB/c mice. It was evident that the presence of aptamer decreased the generalized toxicity of MPS-Apt, as measured by mean body weight loss and blood profiles, keeping all the blood formed elements level within acceptable limits. The histopathological investigations showed some necrotic and pyknotic bodies. In a similar fashion, liver function test and renal function tests showed pronounced effects of formulations on vital organs.


Assuntos
Receptor ErbB-3/antagonistas & inibidores , Sorafenibe/toxicidade , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Polímeros/química , Solventes/química , Sorafenibe/química
19.
Eur J Pharm Biopharm ; 135: 72-82, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30590107

RESUMO

Non-viral vectors are a safe, efficient and non-toxic alternative to viral vectors for gene therapy against many diseases ranging from genetic disorders to cancers. Polyamidoamine (PAMAM), a positively charged dendrimer has a tendency to complex with nucleic acids (to form dendriplexes) like plasmid DNA (pDNA) and small interfering RNA (siRNA) and can shield them from enzymatic degradation, thereby facilitating endocytosis and endosomal release. In this study, we developed an advanced variant of the dendriplexes by encapsulating them within liposomes to enhance their gene delivery efficiency. This liposome encapsulated dendriplex system can further reduce unwanted cytotoxicity and enhance cellular uptake of nucleic acids. A broad range of lipid combinations were used to optimize the lipodendriplexes in terms of their physicochemical characteristics including size, shape and zeta potential. The optimized lipodendriplexes were tested for pDNA transfection, in vitro cell viability, cellular uptake, siRNA mediated knockdown, hemocompatibility, metastatic progression and in ovo in chorioallantoic membrane model (CAM). The optimized system has shown significant improvement in pDNA transfection (p < 0.01) with higher GFP expression and gene silencing and has shown improved cell viability (p < 0.05) compared to the parent dendriplex system. The hemocompatibility and CAM analysis, revealed an efficient yet biocompatible gene delivery system in the form of lipodendriplexes.


Assuntos
Dendrímeros/química , Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos , Animais , Linhagem Celular , Sobrevivência Celular/genética , Galinhas , Membrana Corioalantoide/metabolismo , DNA/administração & dosagem , Técnicas de Silenciamento de Genes , Inativação Gênica , Vetores Genéticos/efeitos adversos , Proteínas de Fluorescência Verde/genética , Humanos , Lipídeos/química , Lipossomos , Nanoestruturas , Plasmídeos/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Transfecção
20.
Biomed Res Int ; 2016: 6068429, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27366750

RESUMO

Majority of gram negative pathogenic bacteria are responsible for extended spectrum ß-lactamases (ESBLs) production, which show resistance to some newer generation of antibiotics. The study was aimed at evaluating the prevalence of ESBL and antibiotic susceptibility pattern of Pseudomonas isolates collected during 2010 to 2014 from tertiary care hospitals of Peshawar, Pakistan. Out of 3450 samples, 334 Pseudomonas spp. isolates comprised of 232 indoor and 102 outdoor patients were obtained from different specimens and their susceptibility pattern was determined against 20 antibiotics. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer agar diffusion method and ESBL production was detected by Synergy Disc Diffusion technique. The mean age group of the patients was 29.9 + 9.15 years. Meronem showed best activity (91.02%) from class carbapenem, ß-lactam and ß-lactamase inhibitors exhibited 69.16% activity, and doxycycline had a diminished activity (10.18%) to Pseudomonas spp. Outdoor isolates were more resistant than the indoor and during the course of the study the sensitivity rate of antibiotics was gradually reducing. ESBL production was observed in 44.32% while the remaining was non-ESBL. The moderate active antibiotics were amikacin (50.7%), SCF (51.4%), TZP (52.7%), and MXF (54.1%) among ESBL producing isolates. Lack of antibiotic policy, irrational uses (3GCs particularly), and the emergence of antibiotic resistant organisms in hospitals may be causes of high antibiotic resistance.


Assuntos
Antibacterianos/administração & dosagem , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas/efeitos dos fármacos , Pseudomonas/enzimologia , beta-Lactamases/biossíntese , Adulto , Distribuição por Idade , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Prevalência , Pseudomonas/classificação , Infecções por Pseudomonas/tratamento farmacológico , Fatores de Risco , Distribuição por Sexo , Especificidade da Espécie , Resistência beta-Lactâmica/efeitos dos fármacos
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