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1.
Colloids Surf B Biointerfaces ; 206: 111935, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34252691

RESUMO

Silver nanoparticles (AgNPs) could be employed in the combat against COVID-19, yet are associated with toxicities. In this study, biogenic and biocompatible AgNPs using the agro-waste, non-edible Hibiscus sabdariffa stem were synthesized. Under optimized reaction conditions, synthesized green AgNPs were crystalline, face cubic centered, spherical with a diameter of around 17 nm and a surface charge of -20 mV. Their murine lethal dose 50 (LD50) was 4 folds higher than the chemical AgNPs. Furthermore, they were more murine hepato- and nephro-tolerated than chemical counterparts due to activation of Nrf-2 and HO-1 pathway. They exerted an apoptotic anti-ovarian cancer activity with IC50 value 6 times more than the normal cell line. Being functionalized with polydopamine and conjugated to either moxifloxacin or gatifloxacin, the conjugates exerted an augmented antibiofilm activity against Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii biofilms that was significantly higher than antibiotic alone or functionalized AgNPs suggesting a synergistic activity. In conclusion, this study introduced a facile one-pot synthesis of biogenic and biocompatible AgNPs with preferential anti-cancer activity and could be utilized as antibiotic delivery system for a successful eradication of Gram-negative biofilms.


Assuntos
Antibacterianos , Nanopartículas Metálicas , Prata , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Química Verde , Hibiscus , Indóis , Camundongos , Testes de Sensibilidade Microbiana , Polímeros , Prata/farmacologia
2.
Mater Sci Eng C Mater Biol Appl ; 122: 111921, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641914

RESUMO

Carbon nanomaterials (CNMs) such as graphene quantum dots (GQDs), graphene oxide nanosheets (GO), single and multiwalled carbon nanotubes (SWCNTs, MWCNTs) exhibit different drug loading capacities, release rates, and targeting abilities. This explains the reported discrepancy of their associated therapeutic efficiencies when used as drug carrier systems. In this study, for the first time, two different types of GQDs named GQDs1 and GQDs2 were synthesized, fully characterized, loaded with the chemotherapeutic Doxorubicin (DOX) and compared with other CNMs under the same conditions. The effects of shape (spheres, tubes and sheets), size (30-180 nm), and surface charge (-64.9 to -11.85 mv) of the synthesized CNMs on DOX loading and release efficiency as well as cytotoxicity against MCF-7 cells were investigated. Furthermore, the biosafety of the synthesized GQDs was studied both at the in vitro level using human WI-38 cells and at the in vivo level at low and high doses of 5 and 20 mg/Kg using healthy female Wister rats. Results revealed that GO nanosheets showed the highest DOX loading capacity reaching 2.85 mg/mg while GQDs1 exhibited the highest release rate of 78.1%. The in vitro cytotoxicity evaluation indicated that the smallest spherical nanomaterial among the tested CNMs, namely GQDs1 was the most efficient one on delivering DOX into the cells and inhibiting their proliferation. Regarding the biosafety, all CNMs displayed no noticeable cytotoxicity against WI-38, except for GQDs2. Moreover, hematological, biochemical and histological assessment of both kidneys and livers of treated rats assured the high biosafety level. We also present new insights on the first principle calculations investigating the adsorption of DOX on GO and GQDs. The calculations showed that DOX molecules adsorbed almost equally on both nanoforms, however, the flaky nature of our GO monolayers allowed for sandwich-like structures to exist making its loading capacity superior over GQDs. Based on this comprehensive study, GQDs is the most promising type of the tested CNMs to be used in further studies.


Assuntos
Grafite , Nanotubos de Carbono , Pontos Quânticos , Animais , Doxorrubicina/farmacologia , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Interações Medicamentosas , Feminino , Humanos , Ratos
3.
J Photochem Photobiol B ; 210: 111963, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32795847

RESUMO

BACKGROUND: Photodynamic therapy with 5-aminolevulinic acid (5-ALA PDT) is a promising novel therapeutic approach in the therapy of malignant brain tumors. 5-ALA occurs as a natural precursor of protoporphyrin IX (PpIX), a tumor-selective photosensitizer. The ATP-binding cassette transporter ABCG2 plays a physiologically significant role in porphyrin efflux from living cells. ABCG2 is also associated with stemness properties. Here we investigate the role of ABCG2 on the susceptibility of glioblastoma cells to 5-ALA PDT. METHODS: Accumulation of PpIX in doxycycline-inducible U251MG glioblastoma cells with or without induction of ABCG2 expression or ABCG2 inhibition by KO143 was analyzed using flow cytometry. In U251MG cells, ABCG2 was inducible by doxycycline after stable transfection with a tet-on expression plasmid. U251MG cells with high expression of ABCG2 were enriched and used for further experiments (sU251MG-V). PDT was performed on monolayer cell cultures by irradiation with laser light at 635 nm. RESULTS: Elevated levels of ABCG2 in doxycycline induced sU251MG-V cells led to a diminished accumulation of PpIX and higher light doses were needed to reduce cell viability. By inhibiting the ABCG2 transporter with the efficient and non-toxic ABCG2 inhibitor KO143, PpIX accumulation and PDT efficiency could be strongly enhanced. CONCLUSION: Glioblastoma cells with high ABCG2 expression accumulate less photosensitizer and require higher light doses to be eliminated. Inhibition of ABCG2 during photosensitizer accumulation and irradiation promises to restore full susceptibility of this crucial tumor cell population to photodynamic treatment.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia , Regulação para Cima/efeitos dos fármacos , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Ácido Aminolevulínico/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxiciclina/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Luz , Proteínas de Neoplasias/genética , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Protoporfirinas/química , Protoporfirinas/metabolismo , Protoporfirinas/uso terapêutico
4.
J Photochem Photobiol B ; 178: 182-191, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29156346

RESUMO

BACKGROUND: Photodynamic therapy (PDT) of malignant brain tumors is a promising adjunct to standard treatment, especially if tumor stem cells thought to be responsible for tumor progression and therapy resistance were also susceptible to this kind of treatment. However, some photosensitizers have been reported to be substrates of ABCG2, one of the membrane transporters mediating resistance to chemotherapy. Here we investigate, whether inhibition of ABCG2 can restore sensitivity to photosensitizer chlorin e6-mediated PDT. METHODS: Accumulation of chlorin e6 in wild type U87 and doxycycline-inducible U251 glioblastoma cells with or without induction of ABCG2 expression or ABCG2 inhibition by KO143 was analyzed using flow cytometry. In U251 cells, ABCG2 was inducible by doxycycline after stable transfection with a tet-on expression plasmid. Tumor sphere cultivation under low attachment conditions was used to enrich for cells with stem cell-like properties. PDT was done on monolayer cell cultures by irradiation with laser light at 665nm. RESULTS: Elevated levels of ABCG2 in U87 cells grown as tumor spheres or in U251 cells after ABCG2 induction led to a 6-fold lower accumulation of chlorin e6 and the light dose needed to reduce cell viability by 50% (LD50) was 2.5 to 4-fold higher. Both accumulation and PDT response can be restored by KO143, an efficient non-toxic inhibitor of ABCG2. CONCLUSION: Glioblastoma stem cells might escape phototoxic destruction by ABCG2-mediated reduction of photosensitizer accumulation. Inhibition of ABCG2 during photosensitizer accumulation and irradiation promises to restore full susceptibility of this crucial tumor cell population to photodynamic treatment.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Dicetopiperazinas/toxicidade , Expressão Gênica/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/toxicidade , Fármacos Fotossensibilizantes/metabolismo , Porfirinas/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Doxiciclina/farmacologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Luz , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Compostos de Fenilureia/farmacologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/toxicidade , Porfirinas/química , Porfirinas/toxicidade , Sorafenibe
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 181: 239-248, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28371723

RESUMO

Levocetirizine dihydrochloride is known to interact with some anti-inflammatory drugs. We report here a comprehensive integrated theoretical and experimental study for the in vitro drug interaction between levocetirizine dihydrochloride (LEV) and diclofenac sodium (DIC). The interaction of the two drugs was confirmed by the molecular ion peak obtained from the mass spectrum of the product. Moreover, FTIR and 1HNMR spectra of the individual drugs and their interaction product were inspected to allocate the possible sites of interaction. In addition, quantum mechanical DFT calculations were performed to search for the interaction sites and to verify the types of interactions deduced from the spectroscopic studies such as charge-transfer and non-bonding π-π interactions. It was found that the studied drugs interact with each other in aqueous solution via four types of interactions, namely, ion-pair formation, three weak hydrogen bonds, non-bonding π-π interactions and charge-transfer from DIC to LEV.


Assuntos
Cetirizina/química , Diclofenaco/química , Cetirizina/análise , Diclofenaco/análise , Ligação de Hidrogênio , Modelos Moleculares , Análise Espectral
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