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1.
Mem Inst Oswaldo Cruz ; 119: e220242, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38198296

RESUMO

BACKGROUND: Eosinophils are granulocytes that rapidly increase frequency in the bloodstream during helminthic infections and allergic responses. They are found in tissue infected by Leishmania during early disease, but their role during infection is not entirely understood. OBJECTIVES: We aim to compare the disease due to Leishmania amazonensis in BALB/c and Δdbl-GATA1 mice, which lack eosinophils. METHODS: BALB/c and Δdbl-GATA1 mice infected with L. amazonensis were observed for several weeks. The parasite load and dissemination pattern were assessed. FINDINGS: The Δdbl-GATA1 mice developed an anticipated dissemination of L. amazonensis and a worsening disease. No differences were found in the lesion development or the parasite load in the footpad among Δdbl-GATA1 mice and BALB/c eight weeks after infection. However, nine weeks after infection, massive growth of metastatic lesions appeared in several parts of the skin in Δdbl-GATA1 mice, weeks earlier than BALB/c. We observed increased parasites in the bloodstream, probably an essential dissemination route. Thirteen weeks after infection, metastatic lesions were found in all Δdbl-GATA1 mice. MAIN CONCLUSION: These results suggest a protective role of eosinophils in delaying the disease caused by L. amazonensis, although several limitations of this mice strain must be considered.


Assuntos
Leishmania mexicana , Leishmania , Animais , Camundongos , Eosinófilos , Carga Parasitária , Pele
2.
Toxicol Appl Pharmacol ; 352: 162-169, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29864484

RESUMO

Doxorubicin (DOX) is widely used in cancer treatment, however, the use of this drug is often limited due to its cardiotoxic side effects. In order to avoid these adverse effects, the encapsulation of DOX into nanosystems has been used in the last decades. In this context, pH-sensitive liposomes have been shown promising for delivering cytotoxic agents into tumor cells, however, the lack of information about in vivo toxicity of this nanocarrier has impaired translational studies. Therefore, the aim of this work was to investigate the acute toxicity and cardiotoxicity of DOX-loading pH-sensitive liposomes (SpHL-DOX). To achieve this, female BALB/c mice, after intravenous administration, were monitored by means of clinical, laboratory, histopathological and electrocardiographic (ECG) analyses. Results indicate that SpHL was able to prevent renal toxicity and the hepatic injury was less extensive than free DOX. In addition, lower body weight loss was associated with less ECG QT interval prolongation to animals receiving SpHL-DOX (14.6 ±â€¯5.2%) compared to animals receiving free DOX (35.7 ±â€¯4.0%) or non-pH-sensitive liposomes (nSpHL-DOX) (47.0 ±â€¯9.8%). These results corroborate with SpHL-DOX biodistribution studies published by our group. In conclusion, the SpHL-DOX showed less toxic effects on mice compared to free DOX or nSpHL-DOX indicating that SpHL-DOX is a promising strategy to reduce the serious cardiotoxic effects of DOX.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Doxorrubicina/toxicidade , Avaliação Pré-Clínica de Medicamentos , Cardiopatias/prevenção & controle , Nefropatias/prevenção & controle , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/química , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Preparações de Ação Retardada , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Composição de Medicamentos , Feminino , Coração/efeitos dos fármacos , Cardiopatias/induzido quimicamente , Cardiopatias/patologia , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Lipossomos , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos Endogâmicos BALB C , Miocárdio/patologia
3.
Fish Shellfish Immunol ; 80: 651-654, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29859314

RESUMO

Recently, chitosan-based nanoparticles with mucoadhesive properties emerged as a strategy for mucosal drug release. This study aimed to characterize the interaction of mucoadhesive system chitosancoated PLGA nanoparticles (NPMA) with fish external mucus. NP suspensions with fluorescent probe were prepared and characterized by size, polydispersity, zeta potential and pH measures. In post-exposure fish were observed an increase in fluorescence imaging over time and it was significantly influenced by NPMA concentration. We also observed the main predominance the fluorescence in the spleen, followed by liver, gill and other tissues. The use of mucoadhesive nanocarriers becomes an alternative for administration of drugs and immunomodulators in immersion systems since the nanosystem can adhere to the mucosal surface of the fish with little residual effect in the water.


Assuntos
Quitosana/administração & dosagem , Portadores de Fármacos/administração & dosagem , Nanopartículas/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Adesividade , Animais , Quitosana/química , Portadores de Fármacos/química , Corantes Fluorescentes/administração & dosagem , Brânquias/metabolismo , Imunomodulação , Fígado/metabolismo , Mucosa/química , Nanopartículas/química , Ácido Poliglicólico/química , Baço/metabolismo , Peixe-Zebra
4.
Toxicol Appl Pharmacol ; 329: 272-281, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28610991

RESUMO

Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors, with a high mortality rate due to the elevated risk of resistance. Natural cucurbitacins and their derivatives are recognized as promising antitumor compounds for several types of cancer, including NSCLC. In a recent study published by our research group, DACE (2-deoxy-2-amine-cucurbitacin E), which is a semisynthetic derivative of cucurbitacin B, showed potential in vitro synergistic antiproliferative effects combined with paclitaxel (PTX) in A549 cells. In sequence, the purpose of this study was to evaluate the in vivo antitumor efficacy of this combined therapy as well as with these drugs individually, using a human NSCLC xenograft model. Some indicators of sub chronic toxicity that could be affected by treatments were also assessed. The results obtained in vivo with the combined treatment (1mg/kg+PTX 10mg/kg) showed the most effective reduction of the relative tumor volume and the highest inhibition of tumor growth and proliferation, when compared with those of the single treatments. Furthermore, scintigraphic images, obtained before and after the treatments, showed that the most effective protocol able to reduce the residual viable tumor mass was the combined treatment. All treatment regimens were well tolerated without significant changes in body weight and no histological and functional damage to liver and kidney tissues. These results corroborate our previous in vitro synergistic effects published. Taken together, these insights are novel and highlight the therapeutic potential of DACE and PTX combination scheme for NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Triterpenos/farmacologia , Células A549 , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Antígeno Ki-67/metabolismo , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Paclitaxel/toxicidade , Compostos Radiofarmacêuticos/administração & dosagem , Fatores de Tempo , Testes de Toxicidade Subcrônica , Triterpenos/toxicidade , Carga Tumoral/efeitos dos fármacos , Imagem Corporal Total , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Nanosci Nanotechnol ; 15(6): 4149-58, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26369024

RESUMO

Inflammatory and infectious diseases are one of the most common causes of mortality and morbidity. This paper aimed to prepare and to evaluate the ability of long-circulating and pH-sensitive liposomes, trapping a radiotracer, to identify inflamed focus. The physicochemical characterization of freeze-dried liposomes, using glucose as cryoprotectant, showed 80% of the vesicles with adequate mean diameter and good vesicle size homogeneity. Radiotracer encapsulation percentage in liposomes was 10.65%, of which 4.88% was adsorbed on the surface of the vesicles. Furthermore, liposomes presented positive zeta potential. Freeze-dried liposomes, stored for 180 days at 4 degrees C, did not show significant changes in the mean diameter, indicating good stability. Free radiotracer and radiolabeled liposomes were injected into inflammation focus-bearing rats, and ex-vivo biodistribution studies and scintigraphic images were performed. Results showed that radiopharmaceutical, free and encapsulated into liposomes, were able to identify the inflamed site. Target/non-target ratios, obtained by scintigraphic images, were greater than 1.5 at all investigated times. Data did not show significant differences between the free radiotracer and radiolabeled liposomes. Results suggest that this liposomal preparation could be employed as an alternative procedure for inflamed site detection by means of scintigraphic images. However, as the radiotracer is adsorbed onto the liposome surface by electrostatic forces, it is suggested that a neutral radiopharmaceutical be used to confirm the potential of this formulation as a scintigraphic probe for inflammation/infection detection.


Assuntos
Inflamação/diagnóstico , Lipossomos/química , Lipossomos/farmacocinética , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Animais , Estabilidade de Medicamentos , Liofilização , Concentração de Íons de Hidrogênio , Inflamação/diagnóstico por imagem , Inflamação/patologia , Masculino , Tamanho da Partícula , Cintilografia , Ratos , Ratos Wistar , Distribuição Tecidual
6.
Bioorg Med Chem Lett ; 24(8): 1998-2001, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24675379

RESUMO

Aptamers are small oligonucleotides that are selected to bind with high affinity and specificity to a target molecule. Aptamers are emerging as a new class of molecules for radiopharmaceutical development. In this study a new method to radiolabel aptamers with technetium-99m ((99m)Tc) was developed. Two aptamers (Apt3 and Apt3-amine) selected against the carcinoembryonic antigen (CEA) were used. Labeling was done by the direct method and the developed complex was subjected to quality control tests. Radiochemical purity and stability were monitored by Thin Layer Chromatography. Binding and specificity assays were carried out in the T84 cell line (CEA+) to evaluate tumor affinity and specificity after radiolabeling. Aptamers were successfully labeled with (99m)Tc in high radiochemical yields, showing in vitro stability in presence of plasma and cystein. In binding assays the radiolabeled aptamer Apt3-amine showed the highest affinity to T84 cells. When evaluated with HeLa cells (CEA-), lower uptake was observed, suggesting high specificity for this aptamer. These results suggest that the Apt3-amine aptamer directly labeled with (99m)Tc could be considered a promising agent capable of identifying the carcinoembryonic antigen (CEA) present in tumor cells.


Assuntos
Aptâmeros de Nucleotídeos/química , Bioensaio , Antígeno Carcinoembrionário/isolamento & purificação , Tecnécio/química , Animais , Antígeno Carcinoembrionário/química , Linhagem Celular , Linhagem Celular Tumoral , Cromatografia em Camada Fina , Estabilidade de Medicamentos , Células HeLa , Humanos , Camundongos , Modelos Moleculares , Neoplasias/diagnóstico
7.
Biomed Pharmacother ; 170: 116054, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38150876

RESUMO

Breast cancer prevails as the most common cancer in women, underscoring an urgent need for more effective therapies. This study explores the potential of our newly developed nanoemulsion containing a novel fucoside derivative of lapachol (NE-F-LapA) as an intravenous treatment strategy. We sought to overcome the solubility issues associated with fucoside with this improved drug delivery strategy that enhances tumor delivery and mitigates other dose-limiting toxicities. Nanoemulsion was prepared and characterized by DLS, zeta potential, encapsulation efficiency, and storage stability. Cytotoxicity against breast cancer cell lines (4T1 and MDA-MB-231) and non-tumor human fibroblasts (NTHF) were evaluated. In vivo assays included antitumoral activity performance and acute systemic toxicity in mice models. NE-F-LapA was synthesized and optimized to 200 nm size, - 20 mV zeta potential, and near-complete (>98%) drug encapsulation. Stability exceeded 6 months, and biological fluid exposure maintained suitable properties for administration. In vitro, NE-F-LapA showed high toxicity (3 µM) against 4T1 and MDA-MB-231, enhanced five times the breast cancer cell uptake and three times the selectivity when compared to normal cells. Systemic toxicity assessment in mice revealed no concerning hematological or biochemical changes. Finally, in a 4T1 breast tumor model, NE-F-LapA significantly inhibited growth by 50% of the subcutaneous 4T1 tumor and reduced lung metastases 5-fold versus control. Overall, tailored nanoemulsification of the lapachol derivative enabled effective intravenous administration and improved efficacy over the free drug, indicating promise for enhanced breast cancer therapy pending further optimization.


Assuntos
Neoplasias da Mama , Nanopartículas , Camundongos , Humanos , Feminino , Animais , Neoplasias da Mama/patologia , Nanopartículas/química , Células MCF-7 , Sistemas de Liberação de Medicamentos , Emulsões/química , Linhagem Celular Tumoral
8.
Pharmaceutics ; 15(2)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36839690

RESUMO

Doxorubicin (DOX) is a potent chemotherapeutic drug used as the first line in breast cancer treatment; however, cardiotoxicity is the main drawback of the therapy. Preclinical studies evidenced that the association of simvastatin (SIM) with DOX leads to a better prognosis with reduced side effects and deaths. In this work, a novel pH-sensitive liposomal formulation capable of co-encapsulating DOX and SIM at different molar ratios was investigated for its potential in breast tumor treatment. Studies on physicochemical characterization of the liposomal formulations were carried out. The cytotoxic effects of DOX, SIM, and their combinations at different molar ratios (1:1; 1:2 and 2:1), free or co-encapsulated into pH-sensitive liposomes, were evaluated against three human breast cancer cell lines (MDA-MB-231, MCF-7, and SK-BR-3). Experimental protocols included cell viability, combination index, nuclear morphological changes, and migration capacity. The formulations showed a mean diameter of less than 200 nm, with a polydispersity index lower than 0.3. The encapsulation content was ~100% and ~70% for DOX and SIM, respectively. A more pronounced inhibitory effect on breast cancer cell lines was observed at a DOX:SIM molar ratio of 2:1 in both free and encapsulated drugs. Furthermore, the 2:1 ratio showed synergistic combination rates for all concentrations of cell inhibition analyzed (50, 75, and 90%). The results demonstrated the promising potential of the co-encapsulated liposome for breast tumor treatment.

9.
Pharmaceutics ; 15(2)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36839905

RESUMO

Cisplatin (CDDP) is a potent antitumor drug used in first-line chemotherapy against several solid tumors, including breast cancer. However, toxicities and drug resistance limit its clinical application. Thermosensitive liposome (TSL) functionalized with hyaluronic acid (HA) containing cisplatin (TSL-CDDP-HA) was developed by our research group aiming to promote the release of CDDP in the tumor region under hyperthermia conditions, as well as to decrease toxicity. Thus, this study aimed to evaluate this new formulation (HA-coated TSL-CDDP) concerning in vitro behavior and in vivo toxicity compared to non-coated TSL-CDDP and free CDDP. Cytotoxicity assays and nuclear morphology were carried out against triple-negative breast cancer cells (MDA-MB-231), while an in vivo toxicity study was performed using healthy Swiss mice. The results showed an increase (around 3-fold) in cytotoxicity of the cationic formulation (non-coated TSL-CDDP) compared to free CDDP. On the other hand, TSL-CDDP treatment induced the appearance of 2.5-fold more senescent cells with alteration of nuclear morphology than the free drug after hyperthermia condition. Furthermore, the association of liposomal formulations treatment with hyperthermia increased the percentage of apoptotic cells compared to those without heating. The percentage of apoptotic cells was 1.7-fold higher for TSL-CDDP-HA than for TSL-CDDP. For the in vivo toxicity data, the TSL-CDDP treatment was also toxic to healthy cells, inducing nephrotoxicity with a significant increase in urea levels compared to the saline control group (73.1 ± 2.4 vs. 49.2 ± 2.8 mg/mL). On the other hand, the HA-coated TSL-CDDP eliminated the damages related to the use of CDDP since the animals did not show changes in hematological and biochemical examinations and histological analyses. Thus, data suggest that this new formulation is a potential candidate for the intravenous therapy of solid tumors.

10.
Biomed Pharmacother ; 165: 115280, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37541172

RESUMO

Doxorubicin (DOX) loaded liposomes have been used and studied in the last decades due to the significant decrease in DOX induced cardiac and systemic toxicity relative to administration of free drug. Therefore, new strategies are sought to improve DOX delivery and antitumor activity, while avoiding side effects. Recently, folate-coated pH-sensitive liposomes (SpHL-Fol) have been studied as a tool to enhance cellular uptake and antitumor activity of paclitaxel and DOX in breast cancer cells expressing folate receptor (FR+). However, the elucidation of folate functionalization relevance in DOX-loaded SpHL (SpHL-DOX-Fol) in different cell types (MDA-MB-231, MCF-7, and A549), as well as, the complete safety evaluation, is necessary. To achieve these objectives, SpHL-DOX-Fol was prepared and characterized as previously described. Antitumor activity and acute toxicity were evaluated in vivo through direct comparison of free DOX verses SpHL-DOX, a well-known formulation to reduce DOX cardiotoxicity. The obtained data are crucial to support future translational research. Liposomes showed long-term stability, suitable for biological use. Cellular uptake, cytotoxicity, and percentage of migration inhibition were significantly higher for MDA-MB-231 (FR+) treated with SpHL-DOX-Fol. In addition, SpHL-DOX-Fol demonstrated a decrease in the systemic toxic effects of DOX, mainly in renal and cardiac parameters evaluation, even using a higher dose (20 mg/kg). Collectively these data build the foundation of support demonstrating that SpHL-DOX-Fol could be considered a promising drug delivery strategy for the treatment of FR+ breast tumors.


Assuntos
Ácido Fólico , Lipossomos , Ácido Fólico/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral
11.
Pharmaceutics ; 15(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38140092

RESUMO

The coating of liposomes with polyethyleneglycol (PEG) has been extensively discussed over the years as a strategy for enhancing the in vivo and in vitro stability of nanostructures, including doxorubicin-loaded liposomes. However, studies have shown some important disadvantages of the PEG molecule as a long-circulation agent, including the immunogenic role of PEG, which limits its clinical use in repeated doses. In this context, hydrophilic molecules as carbohydrates have been proposed as an alternative to coating liposomes. Thus, this work studied the cytotoxicity and preclinical antitumor activity of liposomes coated with a glycosyl triazole glucose (GlcL-DOX) derivative as a potential strategy against breast cancer. The glucose-coating of liposomes enhanced the storage stability compared to PEG-coated liposomes, with the suitable retention of DOX encapsulation. The antitumor activity, using a 4T1 breast cancer mouse model, shows that GlcL-DOX controlled the tumor growth in 58.5% versus 35.3% for PEG-coated liposomes (PegL-DOX). Additionally, in the preliminary analysis of the GlcL-DOX systemic toxicity, the glucose-coating liposomes reduced the body weight loss and hepatotoxicity compared to other DOX-treated groups. Therefore, GlcL-DOX could be a promising alternative for treating breast tumors. Further studies are required to elucidate the complete GlcL-DOX safety profile.

12.
Pharmaceutics ; 14(7)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35890326

RESUMO

The eye is an organ with limited drug access due to its anatomical and physiological barriers, and the usual forms of ocular administration are limited in terms of drug penetration, residence time, and bioavailability, as well as low patient compliance. Hence, therapeutic innovations in new drug delivery systems (DDS) have been widely explored since they show numerous advantages over conventional methods, besides delivering the content to the eye without interfering with its normal functioning. Polymers are usually used in DDS and many of them are applicable to ophthalmic use, especially biodegradable ones. Even so, it can be a hard task to find a singular polymer with all the desirable properties to deliver the best performance, and combining two or more polymers in a blend has proven to be more convenient, efficient, and cost-effective. This review was carried out to assess the use of polymer blends as DDS. The search conducted in the databases of Pubmed and Scopus for specific terms revealed that although the physical combination of polymers is largely applied, the term polymer blend still has low compliance.

13.
Biomed Pharmacother ; 148: 112676, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35149387

RESUMO

Since the discovery of the kahalalide family of marine depsipeptides in 1993, considerable work has been done to develop these compounds as new and biologically distinct anti-cancer agents. Clinical trials and laboratory research have yielded a wealth of data that indicates tolerance of kahalalides in healthy cells and selective activity against diseased cells. Currently, two molecules have attracted the greates level of attention, kahalalide F (KF) and isokahalalide F (isoKF, Irvalec, PM 02734, elisidepsin). Both compounds were originally isolated from the sarcoglossan mollusk Elysia rufescens but due to distinct structural characteristics it has been hypothesized and recently shown that the ultimate origin of the molecules is microbial. The search for their true source has been a subject of considerable research in the anticipation of finding new analogs and a culturable expression system that can produce sufficient material through fermentation to be industrially relevant.


Assuntos
Antineoplásicos , Depsipeptídeos , Neoplasias , Animais , Antineoplásicos/química , Depsipeptídeos/farmacologia , Moluscos/química , Neoplasias/tratamento farmacológico
14.
Pharmaceutics ; 14(2)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35214005

RESUMO

PEGylated liposomes are largely studied as long-circulating drug delivery systems. Nevertheless, the addition of PEG can result in reduced interactions between liposomes and cells, hindering liposomal internalization into target cells. The presence of PEG on the surface of pH-sensitive liposomes is not advantageous in terms of biodistribution and tumor uptake, raising the question of whether the indiscriminate use of PEG benefits the formulation. In this study, two doxorubicin-loaded pH-sensitive liposomal formulations, PEGylated (Lip2000-DOX) or non-PEGylated (Lip-DOX), were prepared and characterized. Overall, the PEGylated and non-PEGylated liposomes showed no differences in size or morphology in Cryo-TEM image analysis. Specifically, DLS analysis showed a mean diameter of 140 nm, PDI lower than 0.2, and zeta potential close to neutrality. Both formulations showed an EP higher than 90%. With respect to drug delivery, Lip-DOX had better cellular uptake than Lip2000-DOX, suggesting that the presence of PEG reduced the amount of intracellular DOX accumulation. The antitumor activities of free-DOX and both liposomal formulations were evaluated in 4T1 breast tumor-bearing BALB/c mice. The results showed that Lip-DOX was more effective in controlling tumor growth than other groups, inhibiting tumor growth by 60.4%. Histological lung analysis confirmed that none of the animals in the Lip-DOX group had metastatic foci. These results support that pH-sensitive liposomes have interesting antitumor properties and may produce important outcomes without PEG.

15.
Polymers (Basel) ; 14(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36433032

RESUMO

Colorectal cancer has been considered a worldwide public health problem since current treatments are often ineffective. Irinotecan is a frontline chemotherapeutic agent that has dose-limiting side effects that compromise its therapeutic potential. Therefore, it is necessary to develop a novel, targeted drug delivery system with high therapeutic efficacy and an improved safety profile. Here, micellar formulations composed of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol)-2000] (DSPE-mPEG2k) containing irinotecan were proposed as a strategy for colorectal cancer therapy. Firstly, the irinotecan-loaded micelles were prepared using the solvent evaporation method. Then, micelles were characterized in terms of size, polydispersity, zeta potential, entrapment efficiency, and release kinetics. Cytotoxicity and in vivo antitumor activity were evaluated. The micelles showed size around 13 nm, zeta potential near neutral (-0.5 mV), and encapsulation efficiency around 68.5% (irinotecan 3 mg/mL) with a sustained drug release within the first 8 h. The micelles were evaluated in a CT26 tumor animal model showing inhibition of tumor growth (89%) higher than free drug (68.7%). Body weight variation, hemolytic activity, hematological, and biochemical data showed that, at the dose of 7.5 mg/kg, the irinotecan-loaded micelles have low toxicity. In summary, our findings provide evidence that DSPE-mPEG2k micelles could be considered potential carriers for future irinotecan delivery and their possible therapeutic application against colorectal cancer.

16.
Talanta ; 243: 123355, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35272155

RESUMO

Mass testing for the diagnosis of COVID-19 has been hampered in many countries owing to the high cost of genetic material detection. This study reports on a low-cost immunoassay for detecting SARS-CoV-2 within 30 min using dynamic light scattering (DLS). The immunosensor comprises 50-nm gold nanoparticles (AuNPs) functionalized with antibodies against SARS-CoV-2 spike glycoprotein, whose bioconjugation was confirmed using transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and surface-enhanced Raman scattering spectroscopy (SERS). The specific binding of the bioconjugates to the spike protein led to an increase in bioconjugate size, with a limit of detection (LOD) 5.29 × 103 TCID50/mL (Tissue Culture Infectious Dose). The immunosensor was also proven to be selective upon interaction with influenza viruses once no increase in size was observed after DLS measurement. The strategy proposed here aimed to use antibodies conjugated to AuNPs as a generic platform that can be extended to other detection principles, enabling technologies for low-cost mass testing for COVID-19.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , COVID-19/diagnóstico , Teste para COVID-19 , Difusão Dinâmica da Luz , Ouro/química , Humanos , Imunoensaio/métodos , Nanopartículas Metálicas/química , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Proteínas Virais
17.
Bioorg Med Chem Lett ; 21(24): 7373-5, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22050889

RESUMO

Long-circulating and pH-sensitive liposomes trapping (99m)Tc-HYNIC-ßAla-bombesin((7-14)) (aSpHL-(99m)Tc-BBN((7-14))) were successfully prepared. Biodistribution studies and scintigraphic images were performed in Ehrlich tumor-bearing Swiss mice. This system showed high accumulation in tumor tissue with high tumor-to-muscle ratio. Therefore, aSpHL-(99m)Tc-BBN((7-14)) could be considered as a potential agent for tumor diagnosis.


Assuntos
Bombesina/análogos & derivados , Lipossomos/química , Animais , Bombesina/administração & dosagem , Bombesina/farmacocinética , Carcinoma de Ehrlich/diagnóstico , Concentração de Íons de Hidrogênio , Marcação por Isótopo , Camundongos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Tecnécio/química , Distribuição Tecidual
18.
Biomed Pharmacother ; 141: 111858, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34323700

RESUMO

Statins, typically used to reduce lipid levels, have been rediscovered for exhibiting anticancer activities. Among them, especially simvastatin may influence the proliferation, migration, and survival of cancer cells. The concept of using statins to treat cancer has been adopted since the 1990s In vitro and in vivo experiments and cohort studies using statins have been carried out to demonstrate their antitumor effects (such as proliferation and migration impairment) by influencing inflammatory and oxidative stress-related tumorigenesis. Nevertheless, the biological mechanisms for these actions are not fully elucidated. In this review, we present an overview of the most important studies conducted from 2015 to date on the use of simvastatin in cancer therapy. This review brings the most recent perspectives and targets in epidemiological, in vitro, and in vivo studies, regarding the use of simvastatin alone or in combination with other drugs for the treatment of various types of cancer.


Assuntos
Antineoplásicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias/tratamento farmacológico , Sinvastatina/uso terapêutico , Animais , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Sinvastatina/farmacologia
19.
Biomed Pharmacother ; 144: 112307, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34653762

RESUMO

Combination therapy between paclitaxel (PTX) and doxorubicin (DXR) is applied as the first-line treatment of breast cancer. Co-administration of drugs at synergistic ratio for treatment is facilitated with the use of nanocarriers, such as liposomes. However, despite the high response rate of solid tumors to this combination, a synergism of cardiotoxicity may limit the use. Thus, the objective of this work was to investigate the toxicity of long-circulating and fusogenic liposomes co-encapsulating PTX and DXR at the synergistic molar ratio (1:10) (LCFL-PTX/DXR). For this, clinical chemistry, histopathological analysis and electrocardiographic exams were performed on female Balb/c mice that received a single intravenous dose of LCFL-PTX/DXR. The results of the study indicated that the LD50 dose range (lethal dose for 50% of animals) of the LCFL-PTX/DXR treatment (28.9-34.7 mg/kg) is much higher than that found for free PTX/DXR treatment (20.8-23.1 mg/kg). In addition, liposomes promoted cardiac protection by not raising CK-MB levels in animals, keeping cardiomyocytes without injury or electrocardiographic changes. After 14 days of treatment, free PTX/DXR caused prolongation of the QRS interval when compared to LCFL-PTX/DXR treatment at the same dose (37.0 ± 5.01 ms and 30.83 ± 2.62 ms, respectively, with p = 0.017). The survival rate of animals treated with LCFL-PTX/DXR was three times higher than that of those treated with free drugs. Thus, it was established that the toxicity of LCFL-PTX/DXR is reduced compared to the combination of free PTX/DXR and this platform has advantages for the clinical treatment of breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Doxorrubicina/toxicidade , Cardiopatias/induzido quimicamente , Lipídeos/química , Miócitos Cardíacos/efeitos dos fármacos , Paclitaxel/toxicidade , Potenciais de Ação/efeitos dos fármacos , Administração Intravenosa , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/química , Cardiotoxicidade , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Composição de Medicamentos , Sinergismo Farmacológico , Eletrocardiografia , Feminino , Cardiopatias/metabolismo , Cardiopatias/patologia , Dose Letal Mediana , Lipossomos , Camundongos Endogâmicos BALB C , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Paclitaxel/administração & dosagem , Paclitaxel/química
20.
Biomed Pharmacother ; 139: 111578, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33848774

RESUMO

The COVID-19 has become of striking interest since the number of deaths is constantly rising all over the globe, and the search for an efficient treatment is more urgent. In light of this worrisome scenario, this opinion review aimed to discuss the current knowledge about the potential role of curcumin and its nanostructured systems on the SARS-CoV-2 targets. From this perspective, this work demonstrated that curcumin urges as a potential antiviral key for the treatment of SARS-CoV-2 based on its relation to the infection pathways. Moreover, the use of curcumin-loaded nanocarriers for increasing its bioavailability and therapeutic efficiency was highlighted. Additionally, the potential of the nanostructured systems by themselves and their synergic action with curcumin on molecular targets for viral infections have been explored. Finally, a viewpoint of the studies that need to be carried out to implant curcumin as a treatment for COVID-19 was addressed.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Curcumina/uso terapêutico , Sistemas de Liberação de Medicamentos , Nanomedicina , Animais , Ensaios Clínicos como Assunto , Humanos
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