RESUMEN
Hemorrhoids are a common ailment that can cause significant disruptions to one's daily life. While some researchers have speculated about a potential link between hemorrhoid development and gut microbes, there is currently insufficient evidence to support this claim. In this study, we collected samples from 60 hemorrhoid patients and analyzed the composition and characteristics of microbiomes in hemorrhoids. PCoA results revealed distinct differences between the microbiomes of hemorrhoids, skin-originated microbiomes, and gut microbes, highlighting the complex nature of hemorrhoidal microbiomes. The distribution characteristics of Staphylococcus suggest that the skin microbiome influences the microbiome of hemorrhoids. Additionally, we observed higher levels of Prevotella in two cases of thrombosed hemorrhoids compared to non-thrombosed hemorrhoids. This finding suggests that Prevotella may play a crucial role in the development of thrombosed hemorrhoids.
RESUMEN
Lung cancer is associated with high morbidity and mortality rates. Forkhead box P2 (FOXP2) functions as an antitumor gene in various cancers. However, its role in lung cancer remains to be elucidated. The present study explored the potential role of FOXP2 in lung cancer. mRNA levels and protein expression were determined using RT-qPCR and western blotting, respectively. Functional analysis was performed using the CCK-8, Transwell and TUNEL assays. FOXP2 expression was downregulated in lung cancer. Notably, FOXP2 suppressed the proliferative, migratory and invasive abilities of lung cancer cells and promoted tumor cell apoptosis. In addition, FOXP2 blocked TGFß signaling. However, SRI-011381-stimulated activation of TGFß signaling reversed the effects of overexpressed FOXP2 and promoted the aggressiveness of lung cancer cells. FOXP2 functions as an antitumor gene in lung cancer cells. FOXP2 suppressed the malignant behavior of lung cancer by inactivating TGFß signaling.
RESUMEN
Anal fistula is a common perianal disease that typically develops from an abscess caused by in-flammation in the area. It has long been believed that intestinal microbes play a significant role in its development, considering its close relation to the intestinal environment. This work attempts to identify the microbiomic signatures of anal fistula, and putative sources of microbes by analyzing microbiomes of 7 anal fistula-associated sites in 12 patients. This study found that microbes in anal fistulas may originate from the skin surface in addition to the intestinal tract. This finding was further validated by NMDS analysis, which also indicated that the microbial communities in the inner and outer openings of the fistula were more similar to their surrounding environments. Using MaAslin2, the characteristics of the microbiome were examined, demonstrating a higher similarity between the abundant bacteria in the anal fistula samples and those found on the skin surface. Moreover, pin-to-pair analysis conducted on all subjects consistently showed a higher abundance of skin-sourced bacteria in anal fistulas. This study identifies the microbiomic signatures of anal fistula, and provides novel insights into the origin of microorganisms in anal fistulas.
Asunto(s)
Microbiota , Fístula Rectal , Humanos , Piel , Resultado del TratamientoRESUMEN
IMPORTANCE: Tigecycline, a glycecycline antibiotic with broad-spectrum activity against almost all Gram-positive and Gram-negative bacteria, is a highly concerned "last-resort" antibiotic. In addition to plasmid-hosted mobile tet(X) conferring high-level resistance to tigecycline, there are many reports suggesting increased expression of AcrAB-TolC efflux pump leads to tigecycline non-susceptibility. However, the role of mutations in AcrAB-TolC on tigecycline resistance has not been identified. This study reports a novel T188A mutation of the AcrA subunit of AcrAB-TolC complex in a clinical tigecycline-resistant Klebsiella pneumoniae strain and reveals the role of AcrA mutation on tigecycline resistance in K. pneumoniae. High prevalence of A188 type AcrA in hypervirulent multidrug-resistant K. pneumoniae indicates that mutations of the AcrAB-TolC complex may play a larger role in determining bacterial pathogenesis and antibiotic susceptibility than previously expected.
Asunto(s)
Antibacterianos , Infecciones por Klebsiella , Humanos , Tigeciclina/farmacología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Minociclina/farmacología , Aminoácidos , Bacterias Gramnegativas/metabolismo , Bacterias Grampositivas/metabolismo , Mutación , Pruebas de Sensibilidad Microbiana , Infecciones por Klebsiella/microbiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana/genéticaRESUMEN
Although naturally occurring flavonoids have shown beneficial effects on the side effects caused by cisplatin, there are few reports on the protective effect of dihydrochalcone on the cisplatin-induced toxicity. Trilobatin (TLB), as the major sweetener and active ingredient in Lithocarpus polystachyus Rehd, is a dihydrochalcone-like compound that can be present in concentrations of up to 10% or more in tender leaves. Herein, a cisplatin-induced acute kidney injury (AKI) model was established to investigate the protective effect and mechanism of TLB against the cisplatin-induced nephrotoxicity in mice. The results showed that TLB significantly reversed the inhibition of CRE, BUN, and MDA levels compared with the cisplatin group. Furthermore, TLB treatment (50 and 100 mg/kg) for 10 days significantly alleviated cisplatin-induced renal pathological changes. TUNEL staining showed that TLB administration can effectively improve the occurrence of apoptosis of renal tissue cells caused by cisplatin exposure. Importantly, western blot analysis verified that TLB alleviated cisplatin-induced nephrotoxicity by regulating the AKT/MAPK signaling pathway and apoptosis. In summary, our findings showed clearly that TLB has a significant preventive effect on cisplatin-induced AKI.
RESUMEN
Diabetes-associated liver injury becomes a dominant hepatopathy, leading to hepatic failure worldwide. The current study was designed to evaluate the ameliorative effects of ginsenoside Rh1 (G-Rh1) on liver injury induced by T2DM. A T2DM model was established using C57BL/6 mice through feeding with HFD followed by injection with streptozotocin at 100 mg·kg-1.. Then the mice were continuously administered with G-Rh1 (5 and 10 mg·kg-1), to explore the protective effects of G-Rh1 against liver injury. Results showed that G-Rh1 exerted significant effects on maintaining the levels of FBG and insulin, and ameliorated the increased levels of TG, TC and LDL-C induced by T2DM. Moreover, apoptosis in liver tissue was relieved by G-Rh1, according to histological analysis. Particularly, in diabetic mice, it was observed that not only the increased secretion of G6Pase and PEPCK in the gluconeogenesis pathway, but also inflammatory factors including NF-κB and NLRP3 were suppressed by G-Rh1 treatment. Furthermore, the underlying mechanisms by which G-Rh1 exhibited ameliorative effects was associated with its capacity to inhibit the activation of the Akt/FoxO1 signaling pathway induced by T2DM. Taken together, our preliminary study demonstrated the potential mechnism of G-Rh1 in protecting the liver against T2DM-induced damage.
Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animales , LDL-Colesterol/metabolismo , LDL-Colesterol/farmacología , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/farmacología , Ginsenósidos , Insulina/metabolismo , Hígado , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , EstreptozocinaRESUMEN
GlnR activates nitrogen metabolism genes under nitrogen-limited conditions, whereas MtrA represses these genes under nutrient-rich conditions in Streptomyces. In this study, we compared the transcription patterns of nitrogen metabolism genes in a double deletion mutant (ΔmtrA-glnR) lacking both mtrA and glnR and in mutants lacking either mtrA (ΔmtrA) or glnR (ΔglnR). The nitrogen metabolism genes were expressed similarly in ΔmtrA-glnR and ΔglnR under both nitrogen-limited and nutrient-rich conditions, with patterns distinctly different from that of ΔmtrA, suggesting a decisive role for GlnR in the control of nitrogen metabolism genes and further suggesting that regulation of these genes by MtrA is GlnR-dependent. MtrA and GlnR utilize the same binding sites upstream of nitrogen metabolism genes, and we showed stronger in vivo binding of MtrA to these sites under nutrient-rich conditions and of GlnR under nitrogen-limited conditions, consistent with the higher levels of MtrA or GlnR under those respective conditions. In addition, we showed that both mtrA and glnR are self-regulated. Our study provides new insights into the regulation of nitrogen metabolism genes in Streptomyces.
Asunto(s)
Regulación Bacteriana de la Expresión Génica , Streptomyces , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Nitrógeno/metabolismo , Streptomyces/genética , Streptomyces/metabolismoRESUMEN
Although ginseng (Panax ginseng C.A. Meyer) has received extensive attention in the treatment and prevention of type 2 diabetes mellitus (T2DM) in the past few decades, there are few studies on the complications of T2DM. At present, obesity-linked diabetic nephropathy (DN) has become the most prevailing element of the end-stage renal failure in the world. The aim of this work is to evaluate the ameliorative effects of ginsenoside Rh1 (G-Rh1) on DN induced by high fat diet plus streptozotocin (HFD/STZ) through some potential and combined mechanisms of action. The results showed that G-Rh1 treatment at 5 and 10 mg/kg for 8 weeks exerted excellent effects in controlling fasting blood glucose (FBG), improving glucose tolerance, and increasing insulin level. In addition, G-Rh1 effectively prevents the excessive production of advanced glycation end products (AGEs), a diabetic nephropathy marker, in HFD/STZ induced DN mice. Meanwhile, oxidation indicators including SOD, GSH, and MDA were improved by G-Rh1 treatment to varying degrees. It is worth noting that G-Rh1 not only inhibits the secretion of Nox1 and Nox4 in kidney tissues, but also has an inhibitory effect on inflammatory factors and NF-[Formula: see text]B signaling pathway. Importantly, further in-depth research on molecular mechanisms provides vital evidence that the ameliorative effect of G-Rh1 on DN is related to the inhibition of apoptosis and the AMPK/PI3K/Akt signaling pathway. In summary, G-Rh1 may be of great value in improving the treatment of DN although more experimental data is needed.
Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Apoptosis/efectos de los fármacos , Nefropatías Diabéticas/tratamiento farmacológico , Ginsenósidos/farmacología , Inflamación/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Dieta Alta en Grasa , Ginsenósidos/química , Mediadores de Inflamación , Ratones , Estructura Molecular , EstreptozocinaRESUMEN
An extensively-drug resistant (XDR) Escherichia coli W60 was isolated from the urine sample of a patient. The genetic basis for its XDR phenotype was investigated, particularly the basis for its resistance toward ß-lactam/BLI (ß-Lactamase Inhibitor) combinations. Following determination of the XDR phenotype, third generation genomic sequencing was performed to identify genetic structures in E. coli W60. Further cloning analysis was performed to identify determinants of ß-lactam/BLI combination resistance. It was found that E. coli W60 is resistant to nearly all of the tested antibiotics including all commonly used ß-lactam/BLI combinations. Analysis of the genomic structures in E. coli W60 showed two novel transferable plasmids are responsible for the resistance phenotypes. Further genetic analysis showed bla NDM-5 leads to high resistance to ß-lactam/BLI combinations, which was enhanced by co-expressing ble MBL. pECW602 harbors a truncated bla TEM that is not functional due to the loss of the N-terminal signal peptide coding region. Research performed in this work leads to several significant conclusions: the XDR phenotype of E. coli W60 can be attributed to the presence of transferable multidrug resistance plasmids; NDM-5 confers high resistance to ß-lactam/BLI combinations; co-expression of ble MBL enhances resistance caused by NDM-5; the signal peptides of TEM type ß-lactamases are essential for their secretion and function. Findings of this work show the danger of transferable multidrug resistance plasmids and metallo-ß-lactamases, both of which should be given more attention in the analysis and treatment of multidrug resistant pathogens.
RESUMEN
BACKGROUND: IFIT2 (interferon-induced proteins with tetratricopeptide repeats 2), also known as ISG54, is an important interferon-stimulated gene family protein, which has been confirmed to play a crucial role in anti-cancer as well as anti-virus process. In the present study, we aimed to investigate the IFIT2 expression in human non-small-cell cancer (NSCLC) tissues and its clinical implications. METHODS: The immunohistochemistry assay was used to identify the clinical significance and prognostic value of IFIT2 expression in NSCLC tissues. The depletion of IFIT2 was achieved using RNAi approach to assess the role of IFIT2 in the regulation of biological behaviors in human lung cancer cell lines. RESULTS: Decreased IFIT2 expression was found in human NSCLC tissues (both in lung adenocarcinoma and lung squamous cell carcinoma) in contrast to the adjacent normal tissues (both P<0.0001, respectively). We did not find any significant correlations between the IFIT2 expression and patient's clinicopathological features. The survival analysis showed that the overall survival (OS) of patients in IFIT2 low expression group was significantly poorer than that in IFIT2 high expression group (in lung adenocarcinoma: P=0.027; and in lung squamous cell carcinoma: P=0.029). The Cox model analysis also indicated that the distant metastasis (P=0.043) could be used as an independent prognostic factor for lung adenocarcinoma patients, and the lymph node metastasis (P=0.045) and IFIT2 low expression (P=0.020) could be used as independent prognostic factors for lung squamous cell carcinoma patients. Moreover, the depletion of IFIT2 in human lung cancer cell lines A549, H1975 and SK-MES-1 significantly increased the cellular abilities, such as viability, migration and invasion. CONCLUSION: Decreased IFIT2 was involved in the initiation and the progression of human NSCLC, and its underlying mechanisms still needs further investigation.
RESUMEN
Magnetic and fluorescent bifunctional nanocomposites have great potential in biomolecule detection and biological imaging applications. So far, it remains a challenge to prepare bifunctional nanocomposites with high colloidal and fluorescent stability. To address this problem, we utilized a simple ring-opening reaction to conjugate Fe3O4 and CdZnSeS quantum dots (QDs). The surface amine groups of SiO2-coated Fe3O4 nanoparticles (Fe3O4@SiO2) opened the rings of the surface maleic anhydride groups of poly(styrene-co-maleic anhydride)-coated CdZnSeS QDs (QDs@PSMA), and then the resulting nanocomposite was functionalized with Jeffamine M-1000 polyetheramine (JMP) by a ring-opening reaction. The structures and properties of the bifunctional nanocomposites were fully characterized by transmission electron microscopy, dynamic light scattering, spectrofluorometry and vibrating sample magnetometry. The results indicated that the nanocomposites prepared by the conjugation method had dramatically higher quantum yields (QYs) than those prepared by the SiO2 co-encapsulation method. After introducing JMP, the nanocomposites exhibited high fluorescent and colloidal stability over a wide pH range (pH 2-13), a low level of protein adsorption in PBS with 10% fetal bovine serum at 37 °C, and a negligible level of nonspecific binding when incubated with HeLa cells. Sandwich fluoroimmunoassay results indicated that the nanocomposites can be successfully applied in a variety of diagnosis and bioimaging applications.
RESUMEN
Transactivation transcriptional activator (TAT) peptides were conjugated on the octadecyl-quaternized, lysine-modified chitosan to form polymeric liposomes (TAT-PLs) with cholesterol for improving transdermal delivery of local anesthetic lidocaine hydrochloride (LID). In this study, the LID loaded TAT-conjugated polymeric liposomes (LID-TAT-PLs) have been successfully prepared. LID-TAT-PLs were characterized by determination of their particle size, polydispersity, morphology, drug encapsulation efficiency, drug release behavior in vitro, and storage-stability. The skin permeation of LID-TAT-PLs was examined using a Franz diffusion cell mounted with depilated mouse skin in vitro, and penetration of TAT-PLs was visualized by confocal laser scanning microscopy (CLSM). The results showed that LID-TAT-PLs were spherical in solution, with substantially smaller mean diameter (154.7±10.7 nm), higher encapsulation efficiency (80.05±2.64%) and better stability in contrast to conventional liposomes (CLs). From the in vitro skin permeation results, transdermal flux of LID-TAT-PLs was approximately 4.17 and 1.75 times higher than that of LID solution and LID CLs (P<0.05). CLSM studies also confirmed that TAT-PLs reached viable layers of the skin. Hence, the results indicate that LID-TAT-PLs are effective and potential alternative for the LID transdermal formulation.
Asunto(s)
Anestésicos Locales/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Lidocaína/administración & dosificación , Administración Cutánea , Anestésicos Locales/farmacocinética , Animales , Quitosano/química , Colesterol/química , Estabilidad de Medicamentos , Almacenaje de Medicamentos , Femenino , Productos del Gen tat/química , Lidocaína/farmacocinética , Liposomas , Lisina/química , Masculino , Ratones , Microscopía Confocal , Tamaño de la Partícula , Polímeros/química , Absorción CutáneaRESUMEN
Glioblastoma with high mortality has been one of the most serious cancers threatening human health. Because of the present treatment limitations, there is an urgent need to construct a multifunctional vesicle for enhancing the treatment of in situ malignant glioblastoma. In our study, drug and gene co-loaded magnetic PLGA/multifunctional polymeric liposome (magnetic PLGA/MPLs) core-shell nanospheres were constructed. They were mainly self-assembled from two parts: hydrophobic PLGA cores that can load drugs and magnetic nanocrystals; and polymeric lipid shells anchored with functional molecules such as PEG chains, TAT peptides and RGD peptides that can help the vectors to condense the gene, prolong the circulation time, cross the blood brain barrier and target delivery to the cancer tissue. The results showed that the magnetic PLGA/MPLs nanosphere has a nanosized core-shell structure, can achieve sustained drug release and has good DNA binding abilities. Importantly, compared with the control group and other groups with single functionality, it can co-deliver the drug and gene into the same cell in vitro and show the strongest inhibiting effect on the growth of the in situ malignant glioblastoma in vivo. All of these results indicated that the different functional components of magnetic PLGA/MPLs, can form an organic whole and none of them can be dispensed with. The magnetic PLGA/MPLs nanosphere may be another option for treatment of glioblastoma.
Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Portadores de Fármacos/administración & dosificación , Epirrubicina/administración & dosificación , Glioblastoma/tratamiento farmacológico , Nanosferas/química , Plásmidos/administración & dosificación , Animales , Antineoplásicos/química , Antineoplásicos/farmacocinética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Sistemas de Liberación de Medicamentos , Epirrubicina/química , Epirrubicina/farmacocinética , Técnicas de Transferencia de Gen , Glioblastoma/metabolismo , Glioblastoma/patología , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Ácido Láctico/administración & dosificación , Ácido Láctico/química , Nanopartículas de Magnetita , Plásmidos/genética , Plásmidos/farmacocinética , Ácido Poliglicólico/administración & dosificación , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Espectroscopía Infrarroja por Transformada de Fourier , Estómago/citología , Estómago/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
One of the most urgent medical requirements for cancer diagnosis and treatment is how to construct a multifunctional vesicle for simultaneous diagnostic imaging and therapeutic applications. In our study, superparamagnetic iron oxide nanocrystals (SPIONs) and doxorubicin hydrochloride (DOX) are co-encapsulated into PLGA/polymeric liposome core-shell nanocarriers for achieving simultaneous magnetic resonance imaging and targeting drug delivery. The core-shell nanocarrier was self-assembled from a hydrophobic PLGA core and a hydrophilic folate coated PEGlated lipid shell. The experiment showed that folate-targeting magnetic core-shell nanocarriers show clear core-shell structure, excellent magnetism and controlled drug release behavior. Importantly, the core-shell nanoparticles achieve the possibility of co-delivering drugs and SPIONs to the same cells for enhancing magnetic resonance imaging (MRI) effect and improving drug delivery efficiency simultaneously. Our data suggests that the folate-targeting magnetic core-shell nanocarriers (FMNs) could provide effective cancer-targeting and MRI as well as drug delivery. The FMNs may become a useful nanomedical carrier system for cancer diagnosis and treatment.
Asunto(s)
Antibióticos Antineoplásicos/metabolismo , Medios de Contraste , Doxorrubicina/metabolismo , Portadores de Fármacos , Ácido Fólico/metabolismo , Ácido Láctico/química , Lípidos/química , Imagen por Resonancia Magnética , Nanopartículas de Magnetita , Ácido Poliglicólico/química , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Química Farmacéutica , Medios de Contraste/administración & dosificación , Medios de Contraste/química , Medios de Contraste/metabolismo , Preparaciones de Acción Retardada , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Femenino , Ácido Fólico/química , Células HeLa , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Nanotecnología , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Solubilidad , Propiedades de Superficie , Tecnología Farmacéutica/métodos , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/metabolismoRESUMEN
Polymeric liposomes (PEG/RGD-MPLs), composed of amphiphilic polymer octadecyl-quaternized modified poly (γ-glutamic acid) (OQPGA), PEGylated OQPGA, RGD peptide grafted OQPGA and magnetic nanoparticles, was prepared successfully. These PEG/RGD-MPLs could be used as a multifunctional platform for targeted drug delivery. The results showed that PEG/RGD-MPLs were multilamellar spheres with nano-size (50-70 nm) and positive surface charge (28-42 mV). Compared with magnetic conventional liposomes (MCLs), PEG/RGD-MPLs exhibited sufficient size and zeta potential stability, low initial burst release and less magnetic nanoparticles leakage. The cell uptake results suggested that the PEG/RGD-MPLs (with RGD and magnetic particles) exhibited more drug cellular uptake than non RGD and non magnetism carriers in MCF-7 cells. MTT assay revealed that PEG/RGD-MPLs showed lower in vitro cytotoxicity to GES-1cells at ≤ 100 µg/mL. These data indicated that the multifunctional PEG/RGD-MPLs may be an alternative formulation for drug delivery system.
Asunto(s)
Antibióticos Antineoplásicos/metabolismo , Neoplasias de la Mama/metabolismo , Epirrubicina/metabolismo , Lípidos/química , Magnetismo , Nanopartículas , Oligopéptidos/metabolismo , Polietilenglicoles/química , Ácido Poliglutámico/análogos & derivados , Compuestos de Amonio Cuaternario/química , Tecnología Farmacéutica/métodos , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/toxicidad , Línea Celular Tumoral , Química Farmacéutica , Preparaciones de Acción Retardada , Composición de Medicamentos , Estabilidad de Medicamentos , Epirrubicina/química , Epirrubicina/toxicidad , Femenino , Mucosa Gástrica/efectos de los fármacos , Humanos , Cinética , Lípidos/toxicidad , Liposomas , Micelas , Estructura Molecular , Nanotecnología , Oligopéptidos/química , Oligopéptidos/toxicidad , Tamaño de la Partícula , Polietilenglicoles/toxicidad , Ácido Poliglutámico/química , Ácido Poliglutámico/toxicidad , Compuestos de Amonio Cuaternario/toxicidad , Solubilidad , Propiedades de SuperficieRESUMEN
The purpose of this study was to use polymeric liposomes (PLs) with a targeting ligand (folate) to coat superparamagnetic iron oxide nanoparticles (SPIONs) and transfer the magnetic nanoparticles from organic phases to aqueous solutions, and further evaluate their efficacy as a magnetic resonance imaging (MRI) contrast agent. The formed nanoparticles exhibited a narrow range of size dispersity (core size of the particles is about 8-10 nm) and relatively high T2 relaxivities (r2 = 164.14 s(-1) mM(-1) for folate-PLs-coated SPIONs). The in vitro tumor cell targeting efficacy of the folate functionalized and PLs-coated SPIONs was evaluated upon observing cellular uptake of magnetite liposomes by HeLa cells, which overexpresses surface receptors for folic acid. In the Prussian blue staining experiments, cells incubated with folate-PLs-coated SPIONs showed much higher intracellular iron density than did the cells incubated with the folate-free PLs-coated SPIONs. Meanwhile, the MTT assay explains the negligible cell cytotoxicity of SPIONs and folate-PLs-coated SPIONs. In HeLa cells, the in vitro MRI study also indicates the better T2-weighted images in folate-PLs-coated SPIONs than in folate-free PLs-coated SPIONs.
Asunto(s)
Medios de Contraste , Liposomas , Imagen por Resonancia Magnética , Nanopartículas de Magnetita , Neoplasias/diagnóstico , Polímeros , Células Cultivadas , Medios de Contraste/química , Células HEK293 , Células HeLa , Humanos , Liposomas/química , Nanopartículas de Magnetita/química , Polímeros/químicaRESUMEN
Chemotherapy is one of the most effective approaches to treat cancers in the clinic, but the problems, such as multidrug resistance (MDR), low bioavailability and toxicity, severely constrain the further application of chemotherapy. Our group recently reported that cationic PLGA/folate coated PEGlated polymeric liposome core-shell nanoparticles (PLGA/FPL NPs). It was self-assembled from a hydrophobic PLGA core and a hydrophilic folate coated PEGlated lipid shell for targeting co-delivery of drug and gene. Hydrophobic drugs can be incorporated into the core and the cationic shell of the drug-loaded nanoparticles can be used to bind DNA. The drug-loaded PLGA/FPL NPs/DNA complexes offer advantages to overcome these problems mentioned above, such as co-delivery of drugs and DNA to improving the chemosensitivity of cancer cells at a gene level, and targeting delivery of drug to the cancer tissue that enhance the bioavailability and reduce the toxicity. The experiment showed that nanoparticles have core-shell structure with nanosize, sustained drug release profile and good DNA-binding ability. Importantly, the core-shell nanoparticles achieve the possibility of co-delivering drugs and genes to the same cells with high gene transfection and drug delivery efficiency. Our data suggest that the PLGA/FPL NPs may be a useful drug and gene co-delivery system.