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1.
Zhonghua Nei Ke Za Zhi ; 60(11): 946-953, 2021 Nov 01.
Artículo en Zh | MEDLINE | ID: mdl-34689514

RESUMEN

Rheumatic diseases are a kind of chronic inflammatory diseases mainly involving joints and surrounding tissues. Most patients with rheumatic diseases need long-term treatment, which is difficult to be avoided during pregnancy. Treatment efficacy, as well as maternal and fetal safety should be taken into account in the medical decision. Based on the domestic and foreign guidelines, consensus, diagnosis and treatment experience, Chinese Rheumatology Association developed the standardization of medication use in patients with rheumatic diseases preparing and during pregnancy, aiming on the application and precautions of commonly used medicines for rheumatic diseases in preparing pregnancy, pregnancy and lactation.


Asunto(s)
Enfermedades Reumáticas , Reumatología , Consenso , Femenino , Humanos , Embarazo , Enfermedades Reumáticas/tratamiento farmacológico
2.
Zhonghua Nei Ke Za Zhi ; 59(4): 269-276, 2020 Apr 01.
Artículo en Zh | MEDLINE | ID: mdl-32209192

RESUMEN

Sjögren's syndrome is a chronic systemic autoimmune disease characterized by lymphocyte proliferation and progressive exocrine gland damage. In China, standardized diagnosis and treatment for Sjögren's syndrome lags behind other common rheumatic diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Based on the evidence and guidelines from China and other countries, Chinese Sjögren's Syndrome Collaborative Research Group together with stomatologist and ophthalmologist developed Standardization of diagnosis and treatment of primary Sjögren's syndrome. The purposes are: (1) to standardize the detection and interpretation of key indicators for the diagnosis of Sjögren's syndrome, including serum anti SSA antibody and labial gland pathology; (2) to suggest using widely accepted disease activity index in evaluation of the disease; (3) to standardize rational management for Sjögren's syndrome patients with topical and systemic diseases.


Asunto(s)
Guías de Práctica Clínica como Asunto , Síndrome de Sjögren , China , Humanos , Síndrome de Sjögren/diagnóstico , Síndrome de Sjögren/terapia
5.
J Biol Regul Homeost Agents ; 31(2): 371-376, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28685539

RESUMEN

This paper aimed to analyze the effects of respiratory training on pulmonary function during the rehabilitation period for acute organic fluorine-poisoned patients treated by non-invasive positive pressure ventilation (NIPPV). Sixty-two acute organic fluorine-poisoned patients admitted to the Xinxiang Central Hospital, Xinxiang City, China, from May 2012 to March 2016 were selected and randomly divided into an observation group and a control group, with 31 cases in each. Both groups received NIPPV. The patients in the control group exercised daily, while the patients in the observation group received contracting lips-abdominal breathing training. The therapeutic effects, pulmonary ventilation function, serum levels of α-antitrypsin1 (α-AT1), surfactant protein D (SP-D), neutrophil elastase (NE), transforming growth factor beta 1 (TGF-ß1), and quality of life were analyzed and compared between the two groups both before and after the administration of treatment. The total effective rate of the observation group was 93.55%, which was significantly higher when compared with the control group (74.19%) (P less than 0.05). The levels of forced expiratory volume in one second (FEV1), FEV1/FVC ratio, vital capacity (VC), carbon monoxide diffusion capacity (DLco), and maximal voluntary ventilation (MVV) of the observation group were better when compared with the control group and had statistical significance (P less than 0.05). Before treatment, the serum levels of α-AT1, SP-D, NE, and TGF-ß1, and quality of life had no statistical significance in either group (P>0.05); after treatment, these indexes and the quality of life for the observation group were significantly higher when compared with the control group, with statistical significance (P less than 0.05). The respiratory training in acute organic fluorine-poisoned patients treated by NIPPV can improve the serum indexes, dilute toxicity, and recover pulmonary function, which play key roles in improving the therapeutic effects and quality of life of patients, and is worthy of clinical promotion.


Asunto(s)
Ejercicios Respiratorios , Hidrocarburos Fluorados/envenenamiento , Elastasa de Leucocito/sangre , Respiración con Presión Positiva , Proteína D Asociada a Surfactante Pulmonar/sangre , Factor de Crecimiento Transformador beta1/sangre , alfa 1-Antitripsina/sangre , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
6.
J Fish Biol ; 87(2): 241-55, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26099328

RESUMEN

In this study, the full-length complementary (c)DNA of interleukin-1 receptor-associated kinase 1 gene (irak1) was cloned from common carp Cyprinus carpio. The complete open reading frame of irak1 contained 2109 bp encoding a protein of 702 amino acid residues that comprised a death domain, a ProST region, a serine-threonine-specific protein kinase catalytic domain and a C-terminal domain. The amino-acid sequence of C. carpio Irak1 protein shared sequence homology with grass carp Ctenopharyngodon idellus (84.5%). The phylogenetic tree of IRAKs separated the polypeptides into four clades, comprising IRAK1s, IRAK2s, IRAK3s and IRAK4s. Cyprinus carpio Irak1 fell into the cluster with previously reported IRAK1s including teleost Irak1s. The irak1 gene was highly expressed in gills, followed by brain, skin, hindgut, buccal epithelium, spleen, foregut, head kidney and liver, and was expressed at lowest levels in gonad and muscle. The irak1 messenger (m)RNA expression was up-regulated in liver, spleen, head kidney, foregut, hindgut, gills and skin after stimulation with Vibrio anguillarum and poly(I:C), and significantly high up-regulated expression was observed in liver and spleen. These results implied that irak1 might participate in antibacterial and antiviral innate immunity. These findings gave the indications that irak1 may participate in antibacterial and antiviral immunity.


Asunto(s)
Carpas/genética , Proteínas de Peces/metabolismo , Inmunidad Innata , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Secuencia de Aminoácidos , Animales , Infecciones Bacterianas/inmunología , Carpas/inmunología , Clonación Molecular , ADN Complementario/genética , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Quinasas Asociadas a Receptores de Interleucina-1/genética , Quinasas Asociadas a Receptores de Interleucina-1/inmunología , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Filogenia , ARN Mensajero/metabolismo
8.
Tissue Antigens ; 79(3): 157-64, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22309257

RESUMEN

Non-classical human leukocyte antigen (HLA)-DM plays an important and unique role in the processing and presentation of exogenous antigens. Polymorphisms of certain genes and frequency of alleles in populations may indicate susceptibility to certain diseases. In this study, the analysis of HLA-DMA and HLA-DMB gene polymorphisms and haplotypes in the Chinese Han population was conducted to obtain population genetic data. HLA-DM typing has been performed previously by other groups by polymerase chain reaction (PCR)-restriction fragment length polymorphism and PCR-sequence-specific oligonucleotide probe techniques. In this study, we established a TaqMan PCR typing method as an alternative to these techniques to survey the frequency of DMA and DMB alleles in the population. Genotyping was conducted in 1000 unrelated individuals of Han nationality in South and North China using TaqMan PCR typing. Four different DMA alleles and six different DMB alleles were detected. All loci met the Hardy-Weinberg equilibrium principle that both allele and genotype frequencies in a population remain constant. We found that the DMA*01:01 (69.35%) and DMB*01:01 (52.5%) alleles were more frequent in Chinese Hans. Analysis of the haplotypes for two loci of DMA and DMB showed that a highly significant positive linkage disequilibrium (LD) presented for DMA*01:01-DMB*01:02, DMA*01:01-DMB*01:03, DMA*01:01-DMB*01:04, DMA*01:02-DMB*01:01, DMA*01:02-DMB*01:05, DMA*01:03-DMB*01:07, and DMA*01:04-DMB*01:01 haplotypes. Analysis of haplotypes for four loci associated with antigen processing (DMA-DMB-TAP1-TAP2) showed a highly significant LD in DMA*01:01-DMB*01:04-TAP1*02:01:01-TAP2*01:02, DMA*01: 02-DMB*01:05-TAP1*01:01-TAP2*01:01, and DMA*01:01-DMB*01:03-TAP1* 04:01-TAP2*01:01 haplotypes. The comparison between the Chinese Han population and non-Chinese populations showed that no significant differences were found at the HLA-DMA locus in the Chinese Han population compared with people of German nationality, whereas significant differences presented when compared with Turkish, American Caucasian, Japanese, French, and Italian nationalities. However, at the HLA-DMB locus, highly significant differences presented in the Chinese Han population compared with Germans and Italians. This study lays the foundations for further disease association analyses.


Asunto(s)
Pueblo Asiatico/genética , Antígenos HLA-D/genética , Polimorfismo Genético , China/etnología , Frecuencia de los Genes , Antígenos HLA-D/sangre , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple/genética , Población Blanca/genética
9.
Transfus Med ; 21(5): 338-43, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21658139

RESUMEN

OBJECTIVES/AIMS: We investigated the incidence of immunoglobulin A (IgA) deficiency in Chinese population. BACKGROUND: The frequency of IgA deficiency, defined as a serum IgA level of <0.05 mg dL(-1) , has been broadly studied in different ethnic groups. Individuals with IgA deficiency may form specific antibodies against IgA, which can cause an anaphylactic response when the patient receives an IgA-containing blood transfusion. METHODS: A sandwich enzyme-linked immunosorbent assay was performed to screen for IgA deficiency and particle gel immunoassay used for confirmation. IgA antibodies were further detected by the DiaMed anti-IgA test in IgA-deficient blood donors. RESULTS: Of the total 22,609 healthy blood donors screened, only seven cases were confirmed as having IgA deficiency (<0.05 mg dL(-1) ). Another seven cases displayed relative IgA deficiencies, with mean IgA concentrations ranging from 0.39 to 3.70 mg dL(-1) . Anti-IgA was identified in 2 of the 14 IgA-deficient blood donors whose IgA levels were <5 mg dL(-1) . Estimation of the theoretical risk for IgA anaphylactic transfusion reaction was 0.009%. CONCLUSION: The prevalence of IgA deficiency in Chinese is low. However, potential risks exist in performing blood transfusion to IgA-deficient persons, and measures should be taken to reduce IgA anaphylaxis.


Asunto(s)
Anafilaxia/etiología , Donantes de Sangre , Deficiencia de IgA/diagnóstico , Deficiencia de IgA/epidemiología , Reacción a la Transfusión , Anafilaxia/epidemiología , Anafilaxia/prevención & control , Pueblo Asiatico , Ensayo de Inmunoadsorción Enzimática , Humanos , Deficiencia de IgA/inmunología , Isoanticuerpos/sangre , Tamizaje Masivo , Prevalencia
10.
Pharmacogenomics J ; 9(6): 411-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19488064

RESUMEN

Though Deflazacort and prednisone improve clinical endpoints in Duchenne muscular dystrophy (DMD) patients, Deflazacort produces fewer side effects. As mechanisms of improvement and side effect differences remain unknown, we evaluated effects of corticosteroid administration on gene expression in blood of DMD patients. Whole blood was obtained from 14 children and adolescents with DMD treated with corticosteroids (DMD-STEROID) and 20 DMD children and adolescents naïve to corticosteroids (DMD). The DMD-STEROID group was further subdivided into Deflazacort and prednisone groups. Affymetrix U133 Plus 2.0 expression microarrays were used to evaluate mRNA expression. Expression of 524 probes changed with corticosteroids, including genes in iron trafficking and the chondroitin sulfate biosynthesis pathway. Deflazacort compared with prednisone yielded 508 regulated probes, including many involved in adipose metabolism. These genes and pathways help explain mechanisms of efficacy and side effects of corticosteroids, and could provide new treatment targets for DMD and other neuromuscular disorders.


Asunto(s)
Expresión Génica/efectos de los fármacos , Distrofia Muscular de Duchenne/sangre , Distrofia Muscular de Duchenne/genética , Prednisona/uso terapéutico , Pregnenodionas/uso terapéutico , Tejido Adiposo/metabolismo , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Sulfatos de Condroitina/biosíntesis , Perfilación de la Expresión Génica , Humanos , Hierro/metabolismo , Distrofia Muscular de Duchenne/tratamiento farmacológico , ARN Mensajero/sangre , Estudios Retrospectivos
11.
Tissue Antigens ; 72(5): 441-7, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18764808

RESUMEN

The heterodimeric transporter associated with antigen processing (TAP) complex plays a key role in immune surveillance. TAP1 and TAP2 typing was usually performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism and PCR-sequence-specific oligonucleotide probe. As an alternative to these methods, we have established TaqMan assays to determine the frequencies of the TAP1 and TAP2 alleles. We have used these new TaqMan assays to genotype the polymorphisms in 339 unrelated Chinese Hans residing in North and South China. We detected five TAP1 and four TAP2 alleles. All the loci conform to the Hardy-Weinberg expectations. The most frequent alleles in Chinese Hans were TAP1*0101 (79.79%) and TAP2*0101 (82.74%). The two-locus haplotype analysis showed highly significant positive linkage disequilibrium for one TAP1-TAP2 haplotype (TAP1*020101-TAP2*0102), three TAP1-DRB1 haplotypes (TAP1*020101-DRB1*03, TAP1*020102-DRB1*13, and TAP1*0301-DRB1*16), and three TAP2-DRB1 haplotypes (TAP2*0102-DRB1*09, TAP2*0103-DRB1*04, and TAP2*0201-DRB1*01). The three-locus haplotype analysis showed highly significant positive linkage disequilibrium for TAP1*0101-TAP2*0101-DRB1*07, TAP1*0101-TAP2*0103-DRB1*04, TAP1*020101-TAP2*0101-DRB1*03, and TAP1*020101-TAP2*0102-DRB1*13. Comparison of the allele frequencies with those of other populations showed that the TAP1 allele distribution was very similar in all the groups, except for the Guarani, Kaingang, and Anatolian populations, but TAP2 distribution was significantly different from that of the other populations. The new TaqMan method provides relatively accurate, high-resolution, simple, and fast assays for TAP genotyping.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Frecuencia de los Genes , Haplotipos/genética , Reacción en Cadena de la Polimerasa/métodos , Transportador de Casetes de Unión a ATP, Subfamilia B, Miembro 2 , Miembro 3 de la Subfamilia B de Transportadores de Casetes de Unión a ATP , Alelos , China , Genética de Población , Genotipo , Humanos , Polimorfismo Genético
12.
Acta Neurochir Suppl ; 105: 43-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19066080

RESUMEN

The mechanisms accounting for variable increases in blood flow and seizures following intracerebral hemorrhage (ICH) are unknown. Local cerebral glucose utilization (LCGU) studies performed to address this issue demonstrate increased LCGU within hours around an ICH that is blocked by NMDA and AMPA glutamate receptor antagonists. Local injections of NMDA or AMPA increased LCGU whereas glutamate did not, suggesting an ICH effect on glutamate uptake or glutamate receptors. To address these possibilities, we performed genomic studies of brain following ICH. Among the many regulated genes, an Src family member, Lyn, increased expression over 20-fold. This was important, since Src is known to phosphorylate NMDA receptors and augment their function, and thrombin is known to activate PARs that activate Src. This prompted us to study the Src antagonist, PP2. PP2 decreased LCGU and cell death around ICH and improved behavioral function following ICH. This data leads us to suggest our hypothesis, that ICH, possibly via thrombin activation of protease-activated receptors, activates Src that phosphorylates NMDA receptors and other proteins that mediate injury after ICH.


Asunto(s)
Hemorragia Cerebral/metabolismo , Ácido Glutámico/metabolismo , Síndromes de Neurotoxicidad/etiología , Trombina/metabolismo , Familia-src Quinasas/metabolismo , Animales , Hemorragia Cerebral/complicaciones , Humanos , Síndromes de Neurotoxicidad/tratamiento farmacológico , Receptores de N-Metil-D-Aspartato/metabolismo
13.
Immunohematology ; 23(2): 69-74, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18004937

RESUMEN

B(A) phenotype individuals have normal B antigen and a small amount of A antigen on the RBCs with anti-A in the plasma. Some highly potent monoclonal anti-A reagents are capable of agglutinating B(A) RBCs, which therefore usually results in a discrepancy between RBC and plasma ABO grouping. To date, five B(A) alleles (ABO B(A)01, B(A)02, B(A)03, B(A)04, and B(A)05) have been defined by nucleotide sequences. To get a more complete picture of B(A) phenotypes found in the Chinese population and resolve blood donor typing problems caused by B(A) alleles,a serologic and molecular study of nine unrelated Chinese individuals and three families carrying B(A) alleles was conducted. Allele B(A)02 with a 700C>G mutation, allele B(A)04 with a single 640A>G substitution, and allele B(A)05 with a 641T>C mutation were detected in multigenerational families and unrelated blood donors. Neither the B(A)01 nor B(A)03 alleles with 703A>G substitutions were observed in this study. In addition, a polymerase chain reaction with a sequence-specific primer genotyping assay was developed for rapid identification of B(A)02, B(A)04, and B(A)05 alleles using genomic DNA samples.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Pueblo Asiatico/genética , Sistema del Grupo Sanguíneo ABO/genética , Alelos , Secuencia de Bases , Tipificación y Pruebas Cruzadas Sanguíneas , China/epidemiología , Salud de la Familia , Genotipo , Humanos , Epidemiología Molecular , Linaje , Polimorfismo de Nucleótido Simple
14.
Clin Transl Oncol ; 19(9): 1133-1140, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28397066

RESUMEN

PURPOSE: The objective of the study was to investigate the role of microRNA-9 (miR-9) targeting forkhead box O1 (FOXO1) in the proliferation, migration, and invasion of breast cancer cells. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to determine the expressions of miR-9 and FOXO1 mRNA in breast cancer tissues, normal breast tissues, breast cancer cell lines, and normal breast epithelial cells. After the up-regulation of miR-9 expression, qRT-PCR and Western blotting were used to determine the expression of FOXO1. The luciferase reporter gene assay was used to validate the target gene. The CCK-8 assay, scratch-wound healing assay, and Transwell invasion assay were used to investigate the changes in the proliferation, migration, and invasion of breast cancer cells, respectively. RESULTS: MicroRNA-9 expression was significantly up-regulated in breast cancer tissues and breast cancer cell lines when compared with normal breast tissues and normal breast epithelial cells (both P < 0.05). FOXO1 mRNA and protein expressions were substantially down-regulated in breast cancer tissues and breast cancer cell lines when compared with normal breast tissues and normal breast epithelial cells (both P < 0.05). There can be a negative correlation between miR-9 and FOXO1 mRNA in breast cancer. Luciferase reporter gene assay indicated that miR-9 can down-regulate FOXO1 expression at a post-transcriptional level through binding specifically to FOXO1 3'UTR. The results of CCK-8 assay, scratch-wound healing assay, and Transwell invasion assay revealed that the inhibition of miR-9 can suppress MCF7 cell proliferation, migration, and invasion. Additionally, the expression of miR-9 increased significantly whilst that of FOXO1 decreased substantially as the disease progressed (P < 0.05). CONCLUSIONS: Our study provides evidence that miR-9 can promote the proliferation, migration, and invasion of breast cancer cells via down-regulating FOXO1.


Asunto(s)
Neoplasias de la Mama/genética , Proteína Forkhead Box O1/biosíntesis , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/biosíntesis , Invasividad Neoplásica/genética , Adulto , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo , Femenino , Humanos , Células MCF-7 , Persona de Mediana Edad
16.
Eur Rev Med Pharmacol Sci ; 19(22): 4344-52, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26636522

RESUMEN

OBJECTIVE: Our previous study found that high miR-150 expression was positively correlated with prostate tumor recurrence or metastasis. In this work, we investigated the expression of miR-150 in prostate cancer stem cells (CSCs) and explored its regulation over p27 in the development of CSCs. MATERIALS AND METHODS: MiR-150 expression in CD144 or CD44 positive primary prostate cells and in DU145 cell line was measured. It regulation over CSCs was measured using tumor sphere assay and qRT-PCR analysis of CSC related Oct4, Nestin and Nanog genes. The direct binding between miR-150 and 3'UTR of p27 mRNA was verified using dual luciferase, qRT-PCR and western blot assay. The influence of miR-150-p27 axis on prostate CSC properties was further investigated. RESULTS: Findings of this study found miR-150 expression was significantly upregulated in CD44+ or CD133+ subgroups of prostate cancer cells. MiR-150 could directly target 3'UTR of p27 and decrease its expression, through which it increased the number and volume of tumor sphere formed by DU145 cells, as well as the expression of CSC related Oct4, Nestin and Nanog genes. CONCLUSIONS: Increased miR-150 expression might participate in the development and progression of human prostate CSC by suppressing p27. This supported our previous study which found miR-150 was positively correlated with prostate tumor recurrence or metastasis.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/antagonistas & inhibidores , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/biosíntesis , MicroARNs/biosíntesis , Células Madre Neoplásicas/metabolismo , Neoplasias de la Próstata/metabolismo , Línea Celular Tumoral , Células HEK293 , Humanos , Masculino , Células Madre Neoplásicas/patología , Neoplasias de la Próstata/patología
17.
Thromb Haemost ; 76(2): 245-7, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8865539

RESUMEN

Platelet membrane glycoprotein Ib alpha has at least two polymorphisms which affect phenotype. One is the dimorphism at codon 145, and the other is a molecular weight polymorphism due to variable numbers of tandem repeats (TR) in the macroglycopeptide region. These two polymorphisms are in linkage disequilibrium. The frequencies of these polymorphisms differ considerably depending on race, and the largest variant with four TR is almost exclusively present in the Japanese population. We examined the genotypes of HPA-2 and TR polymorphism in three different races from Eastern Asia; the Japanese (n = 103), Korean (n = 101) and Chinese population (n = 177). The gene frequency of HPA-2 differed significantly among these three populations. Among HPA-2b-positive individuals, the A isoform with four TR and B with three TR were present in all three populations and A dominated over B. Individuals homozygous for the A isoform were found in both Japanese and Korean populations. These findings indicate that the largest haplotype is common in the Eastern Asian region.


Asunto(s)
Pueblo Asiatico/genética , Codón , ADN/genética , Repeticiones de Minisatélite , Complejo GPIb-IX de Glicoproteína Plaquetaria/genética , Polimorfismo Genético , Antígenos de Plaqueta Humana/genética , China , Asia Oriental , Genotipo , Humanos , Japón , Corea (Geográfico) , Valores de Referencia
18.
J Pharm Sci ; 88(11): 1161-8, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10564065

RESUMEN

The intestinal epithelium is a significant barrier for oral absorption of hydrophilic drugs because they cannot easily traverse the lipid bilayer of the cell membrane and their passage through the intercellular space (paracellular transport) is restricted by the tight junctions. In this report we show that dodecylphosphocholine (DPC) can improve the paracellular permeability of hydrophilic compounds across Caco-2 cell monolayers by modulating the tight junctions. The results show that the alkyl chain as well as the zwitterionic head group of DPC are required for its activity. DPC appears to act by modulating the permeability of tight junctions as evidenced by the fact that treatment of Caco-2 cell monolayers by this agent results in a decreased transepithelial electrical resistance (TEER), increased permeability of paracellular markers (e. g., mannitol) with no change in the permeability of the transcellular marker testosterone, and redistribution of the tight junction-associated protein ZO-1. The effect of DPC on Caco-2 cells (e.g., decrease in TEER) is reversible, and is not caused by gross cytotoxicity (as indicated by the MTT test) or by nonspecific disruption of the cell membrane (as indicated by only slight nuclear staining due to the nonpermeable DNA-specific dye propidium iodide). We propose in the present study a parameter, potency index, that allows comparison of various enhancers of paracellular transport in relation to their cytotoxicity. The potency index is a ratio between the IC(50) value (concentration at which 50% inhibition of control mitochondrial dehydrogenase activity occurs in the MTT test) and the EC(50) value (concentration at which TEER drops to 50% of its control (untreated) value). By this parameter, DPC is significantly safer than the commonly used absorption enhancer palmitoyl carnitine (PC), which has the potency index of approximately 1 (i.e., no separation between effective and toxic concentration).


Asunto(s)
Células CACO-2/efectos de los fármacos , Células CACO-2/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Fosforilcolina/análogos & derivados , Células CACO-2/fisiología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/fisiología , Impedancia Eléctrica , Humanos , Cinética , Manitol/farmacocinética , Potenciales de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Palmitoilcarnitina/farmacología , Palmitoilcarnitina/toxicidad , Fosfatidilcolinas/farmacología , Fosfoproteínas/metabolismo , Fosforilcolina/farmacología , Fosforilcolina/toxicidad , Testosterona/farmacocinética , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Uniones Estrechas/fisiología , Proteína de la Zonula Occludens-1
19.
J Pharm Sci ; 88(11): 1169-74, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10564066

RESUMEN

The oral route is the preferred route of delivery for a large number of drug molecules. However, the intestinal epithelium presents a formidable barrier for delivery of drugs into systemic circulation. Phospholipids are among compounds that enhance the absorption of drugs across the intestinal epithelium. In this paper, we describe structure-activity relationships for phospholipid derivatives as enhancers of paracellular permeability across Caco-2 cell monolayers. In a series of 2-alkoxy-3-alkylamidopropylphosphocholine derivatives, compounds with a long chain at C-3 (R3) and short chain at C-2 (R2) were potent in causing a decrease in transepithelial electrical resistance (TEER) and an increase in mannitol transport, but also showed significant cytotoxicity. Compounds with 9-11 carbons at C-3 and 6-10 carbons at C-2 provided good separation (up to 2.7-fold) between activity and cytotoxicity. Notably, a good correlation (r2 = 0.93) was observed between EC(50) (TEER) [concentration that caused a drop in TEER to 50% of its control (untreated) value] and EC10x (mannitol) [concentration that caused 10-fold increase in mannitol transport over the control (untreated) value], confirming that a decrease in TEER is associated with enhanced permeability of the hydrophilic compounds across Caco-2 cell monolayers. Compounds with medium to long carbon chains at C-2 and C-3, and the total carbons in the alkyl chains > 20, showed poor activity and no cytotoxicity.


Asunto(s)
Células CACO-2/efectos de los fármacos , Células CACO-2/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Fosfatidilcolinas/química , Fosfatidilcolinas/farmacología , Células CACO-2/citología , Ácido Edético/farmacología , Impedancia Eléctrica , Humanos , Manitol/farmacocinética , Fosfatidilcolinas/síntesis química , Fosfatidilcolinas/toxicidad , Relación Estructura-Actividad , Uniones Estrechas/efectos de los fármacos , Uniones Estrechas/metabolismo , Uniones Estrechas/fisiología
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