RESUMEN
Recently, much research is focused on the use of photothermal therapy (PTT) as an advanced method to treat various types of cancer. The PTT approach primarily utilizes nanoparticles (NPs) made from metals, carbon, or semiconductors that can convert near-infrared laser irradiation, which penetrates tissues, into local heat that induces cancer cell death. An alternative approach is to utilize NPs (such as liposomes) to carry suitable dye molecules to the same end. Numerous studies concerning PTT have shown that local heat released in cancer cells may suppress the expression of membrane transporter proteins such as P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1), thus enhancing cytotoxicity and reverse multidrug resistance. In addition, because NPs may be loaded with different substances, researchers have designed multifunctional NPs for PTT by including several agents such as membrane transporter modulators, anticancer drugs, and photothermal agents. This review will focus on the recent advances in PTT utilizing various types of NPs, and their components and characteristics. In addition, the role of membrane transporters in PTT will be highlighted and different methods of transporter modulation will be summarized from several PTT studies in which multifunctional NPs were used to treat cancers in vitro and in vivo.
Asunto(s)
Nanopartículas , Neoplasias , Humanos , Terapia Fototérmica , Línea Celular Tumoral , Fototerapia/métodos , Rayos Infrarrojos , Proteínas de Transporte de Membrana , Neoplasias/terapiaRESUMEN
It has been suggested that oral absorption of low-permeable P-glycoprotein (P-gp) substrates can be increased through saturation of P-gp. For BCS class IV drug substances, saturating P-gp is challenging due to low aqueous solubility. The present study investigated if the BCS IV drug substance etoposide could be solubilized to a concentration saturating P-gp after oral administration. A formulation consisting of 10% (w/v) of pluronic® F-127 and polyvinylpyrrolidone/vinyl acetate (PVP/VA), and 57% (v/v) ethanol enhanced etoposide's solubility approximately 100 times (16 mg mL-1) compared to its aqueous solubility. In vitro, this formulation was stable upon dilution in simulated intestinal fluid. In male Sprague-Dawley rats, oral administration of increasing solubilized etoposide doses using the formulation matrix increased the AUC0-∞ of etoposide dose-proportionally but resulted in a lower absolute oral bioavailability (F) and rate of absorption as compared to control. At the highest investigated dose (100 mg kg-1), AUC0-∞ and Cmax were significantly increased by 2.9- and 1.4-fold, respectively, compared to control dosed at 20 mg kg-1. A single oral dose of 20 mg kg-1 zosuquidar followed by 20 mg kg-1 oral etoposide increased F 8.6-fold. In conclusion, a stable formulation with improved etoposide solubility was developed, yet the formulation did not result in increased oral bioavailability of etoposide.
Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Etopósido/administración & dosificación , Etopósido/farmacocinética , Absorción Intestinal , Mucosa Intestinal/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Administración Oral , Animales , Disponibilidad Biológica , Células CACO-2 , Dibenzocicloheptenos/administración & dosificación , Composición de Medicamentos , Estabilidad de Medicamentos , Etanol/química , Etopósido/química , Humanos , Inyecciones Intravenosas , Absorción Intestinal/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Masculino , Modelos Biológicos , Poloxámero/química , Polivinilos/química , Povidona/química , Quinolinas/administración & dosificación , Ratas Sprague-Dawley , SolubilidadRESUMEN
Recently, it has become evident that pharmaceutical excipients may interfere with the activity of ATP-binding cassette (ABC) transporters and solute carriers (SLC). The present review aims to provide an overview of surfactants shown to modulate substrate transport via SLCs and ABCs, and to discuss the relevance for oral drug absorption. In vitro, more than hundred surfactants have been suggested to decrease the efflux activity of P-glycoprotein (P-gp, ABCB1), and many of these surfactants also inhibit the breast cancer resistance protein (BCPR, ABCG2), while conflicting results have been reported for multidrug resistance-associated protein 2 (MRP2, ABCC2). In animals, surfactants such as pluronic® P85 and polysorbate 20 have been shown to enhance the oral absorption of P-gp and BCRP substrates. Many surfactants, including cremophor® EL and Solutol® HS 15 inhibiting ABC transporters, were also found to inhibit SLCs in cell cultures. These carriers were SLC16A1, SLC21A3, SLC21A9, SLC15A1-2, and SLC22A1-3. This overlap in specificity of surfactants that inhibit both transporters and carriers might influence the oral absorption of various drug substances, nutrients, and vitamins. Such biopharmaceutical elements may be relevant for future drug formulation design.
Asunto(s)
Absorción Intestinal/efectos de los fármacos , Proteínas de Transporte de Membrana/metabolismo , Tensoactivos/administración & dosificación , Administración Oral , Animales , Transporte Biológico/efectos de los fármacos , Humanos , Proteína 2 Asociada a Resistencia a Múltiples MedicamentosRESUMEN
Nonionic surfactants commonly used in pharmaceutical formulations may have P-glycoprotein (P-gp) inhibiting and/or permeation enhancing effects. The present work aims to distinguish these effects and assess the degree of cellular recovery after multiple exposures to nonionic surfactants. The investigated surfactants were polysorbates (PS): PS20, PS40, PS60, PS65, PS80 and PS85; monosaccharide-based: lauroyl methyl glucamide and n-nonyl-ß-D-glucopyranoside; or disaccharide-based: lauryl-ß-D-maltoside and trehalose 6-laurate. Bi-directional permeability studies of digoxin and mannitol, and calcein-AM efflux assay were performed in cell cultures. Cellular recovery was evaluated by continuous measurements of transepithelial electrical resistance (TEER) in Caco-2 cell monolayers. Polysorbates with one fatty acid chain decreased the efflux of digoxin through P-gp inhibition in MDCKII MDR1 cells. Mono- and di-saccharide-based surfactants, in a dose dependent manner, enhanced digoxin absorptive permeability without decreasing the secretory permeability in Caco-2 cells, suggesting that the surfactants had a transcellular permeation enhancing effect. Caco-2 cell monolayers recovered to different degrees of 60-100% of the initial TEER values. Calcein-AM assay was found to be non-predictive to surfactants influence on digoxin permeability across cell monolayers. In conclusion, these results may assist, in a mechanism-based, selection of suitable surfactants for formulating oral dosage forms to enhance the absorption of low bioavailable P-gp substrates.
Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Digoxina/farmacología , Polisorbatos/farmacología , Tensoactivos/farmacología , Animales , Células CACO-2 , Perros , Fluoresceínas/farmacología , Humanos , Células de Riñón Canino Madin Darby , Manitol/farmacologíaRESUMEN
The aim of the present work was to investigate the ability of nonionic surfactants to increase the oral absorption of the P-glycoprotein substrate etoposide in vitro and in vivo. Intestinal absorption was investigated by studying bidirectional permeability of etoposide across filter-grown Caco-2 and MDCKII MDR1 cell monolayers. The oral absorption of etoposide was investigated in wild type (WT) and mdr1a deficient (KO) Sprague-Dawley rats. In cell cultures, polysorbate 20 (PS20) decreased P-glycoprotein mediated efflux of etoposide. When PS20 and etoposide were co-administered to WT rats, the oral absorption of etoposide increased significantly in the presence of 5 and 25% (v/v) PS20. However, in KO rats, the exposure of etoposide after oral co-administration with 5% PS20 was similar to control. Unexpectedly, co-administration of etoposide with 25% PS20 significantly reduced the absorption fraction of etoposide in mdr1a KO rats. In vitro dialysis studies performed on PS20-containing etoposide solutions suggested that the reduced bioavailability may be due to etoposide retention in PS20 micelles and/or through increased viscosity. In conclusion, PS20 increases oral bioavailability of etoposide through inhibition of P-glycoprotein. However, the use of the excipient may be challenged by etoposide retention at higher concentrations.