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1.
Int J Gen Med ; 15: 501-511, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35046710

RESUMEN

OBJECTIVE: This study aims to evaluate the clinical value of laparoscopic temporary internal iliac artery blockage (TIIAB) compared with uterine artery embolization (UAE) in type III cesarean scar pregnancy (CSP). METHODS: A total of 76 patients with type III CSP admitted to the Department of Gynecology the First Affiliated Hospital of Zhengzhou University between September 2017 and June 2019 were selected for this retrospective study. Thirty-six of them in the study group received TIIAB, and the rest in control group received UAE. Laparoscopic pregnancy tissue was removed from all patients, and the uterine defects were repaired. The absence of remnants was then confirmed using ultrasonography. Follow-ups were performed in the two groups for six months, and the factors of intraoperative blood loss, operation and menelipsis time, 24-h human chorionic gonadotropin decline rate, postoperative complications, hospitalization days, hospitalization costs, peri-operative hormone levels, and ovarian function indicators were compared between the two groups and within each group. RESULTS: There were statistically significant differences in the hospitalization cost, menelipsis time, and postoperative complication incidence between the two groups (p < 0.05). There were statistically significant differences between ovarian function at one month and three months after surgery (p < 0.05) as well as among the follicle-stimulating hormone, luteinizing hormone, and estradiol levels at one, three, and six months after surgery in the control group (p < 0.05). CONCLUSION: Compared with uterine artery embolization, laparoscopic TIIAB has the advantages of a low hospitalization cost, lower postoperative complication rate, and shorter menelipsis time. Moreover, it avoids ovarian function damage. It is a safe method worthy of clinical popularization.

2.
Life Sci ; 264: 118695, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33130079

RESUMEN

AIMS: Maternal nicotine exposure during pregnancy and lactation is associated with obesity in offspring. Brown adipose tissue (BAT) is correlated with energy metabolism and obesity. In this study, we explored the mechanism of maternal nicotine exposure on BAT changes in male offspring. MAIN METHODS: Pregnant rats were randomly assigned to nicotine (1.0 mg/kg twice per day, subcutaneous administration) or control groups. In vitro, C3H10T1/2 cells were induced to differentiate into mature brown adipocytes, and 0-50 µM nicotine was given to C3H10T1/2 cells during the differentiation process. KEY FINDINGS: Nicotine-exposed males had white-like adipocytes and abnormal mitochondria structure in iBAT at 26 weeks. The expression of mitochondrial genes, UCP1 and AMPK-SIRT1-PGC-1α pathway were downregulated in the nicotine group at 26 weeks rather than 4 weeks. In vitro, 50 µM nicotine decreased the expression of mitochondrial genes, UCP1 and AMPK-SIRT1-PGC-1α pathway in brown adipocytes. SIGNIFICANCE: Maternal nicotine exposure showed the "programming" effect on the decreased brown-like phenotype in BAT of adult male offspring via downregulating AMPK-SIRT1-PGC-1α pathway. This impairment of BAT may be a potential mechanism of nicotine-induced obesity in male offspring.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Tejido Adiposo Pardo/metabolismo , Nicotina/efectos adversos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Efectos Tardíos de la Exposición Prenatal/patología , Transducción de Señal , Sirtuina 1/metabolismo , Tejido Adiposo Pardo/patología , Tejido Adiposo Pardo/ultraestructura , Animales , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Genes Mitocondriales , Masculino , Embarazo , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Proteína Desacopladora 1/metabolismo
3.
Toxicol Appl Pharmacol ; 409: 115298, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33091441

RESUMEN

Maternal nicotine exposure during pregnancy and lactation is associated with obesity in female offspring. Brown adipose tissue (BAT) is related to energy metabolism and obesity. In this study, we explored the mechanism of maternal nicotine exposure on BAT "whitening" in female offspring. Pregnant rats were randomly assigned to nicotine (1.0 mg/kg twice per day, subcutaneous administration) or control groups. The weight, structure, and microvascular density of interscapular BAT (iBAT) and the expression of PGC-1αUCP1 signals, mitochondrial biogenesis-related genes and angiogenesis-related genes were tested in 4- and 26-week-aged female offspring. In vitro, C3H10T1/2 cells were induced to differentiate into mature brown adipocytes, and 0-50 µM nicotine was treated on cells during the differentiation process. Nicotine-exposed females had higher iBAT weight, white-like adipocytes and abnormal mitochondrial structure in iBAT at 26 weeks rather than 4 weeks. The PGC-1αUCP1 signals and brown-like genes were down-regulated at 26 weeks, but the microvascular density and the expression of pro-angiogenic factors reduced more at 4 weeks in the nicotine group. In vitro, 50 µM nicotine significantly decreased the expression of PGC-1αUCP1 signals and angiogenesis-related genes. In conclusion, maternal nicotine exposure during pregnancy and lactation led to the "whitening" of BAT in adult female offspring: nicotine decreased BAT angiogenesis in the early development stage, and then, the impairment of blood vessels programed for the reduction of BAT phenotype through down-regulating the PGC-1αUCP1 signals in adulthood. This impairment of BAT may be a potential mechanism of nicotine-induced obesity in female offspring.


Asunto(s)
Adipocitos Marrones/efectos de los fármacos , Tejido Adiposo Pardo/efectos de los fármacos , Lactancia/efectos de los fármacos , Exposición Materna/efectos adversos , Nicotina/efectos adversos , Animales , Peso Corporal/efectos de los fármacos , Línea Celular , Femenino , Masculino , Ratones , Obesidad/fisiopatología , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Ratas , Ratas Wistar
4.
Toxicol Lett ; 318: 12-21, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31622651

RESUMEN

Maternal smoking during pregnancy and lactation is associated with increased fat mass in the offspring, but the mechanism by which this occurs is not fully understood. Our study focused on the relationships among maternal nicotine exposure, adipose angiogenesis and adipose tissue function in female offspring. Pregnant rats were randomly assigned to nicotine or control groups. Microvascular density, lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins were tested in 4-, 12- and 26-week female offspring. In vitro, nicotine concentration- and time-response experiments were conducted in 3T3-L1. Lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins were tested. The conditioned media of differentiated 3T3-L1 treated with nicotine were used to observe tube formation in human umbilical vein endothelial cells (HUVECs). Nicotine-exposed females presented higher adipose microvascular density. The gene expression of α7nAChR, Egr1 and FGF2 was significantly increased in gonadal white adipose tissue (gWAT) and inguinal subcutaneous WAT (igSWAT) of nicotine-exposed females at 4 weeks of age. The protein expression of α7nAChR, Egr1 and FGF2 was increased in gWAT and igSWAT of nicotine-exposed females at 4 weeks of age, and increased in gWAT at 26 weeks. In vitro, nicotine increased the expression of lipid metabolism and α7nAChR-Egr1-FGF2 signaling pathway genes/proteins in a concentration- and time-dependent manner. In the tube formation experiment, adipocytes affected by nicotine promoted HUVEC angiogenesis. Therefore, maternal nicotine exposure promoted the early angiogenesis of adipose tissue via the α7nAChR-Egr1-FGF2 signaling pathway, and this angiogenesis mechanism was associated with increased adipogenesis in adipose tissue of female offspring.


Asunto(s)
Adipocitos/efectos de los fármacos , Tejido Adiposo Blanco/irrigación sanguínea , Neovascularización Fisiológica/efectos de los fármacos , Nicotina/toxicidad , Agonistas Nicotínicos/toxicidad , Efectos Tardíos de la Exposición Prenatal , Células 3T3-L1 , Adipocitos/metabolismo , Animales , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Femenino , Factor 2 de Crecimiento de Fibroblastos/genética , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Exposición Materna , Ratones , Embarazo , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Receptor Nicotínico de Acetilcolina alfa 7/genética , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
5.
Artículo en Inglés | MEDLINE | ID: mdl-31010129

RESUMEN

Secondhand smoke (SHS), a common environmental exposure factor, has become a serious public health problem. Metabolic syndrome is another worldwide clinical challenge. Our study tried to determine the age differences in the relationship between SHS and the risk of metabolic syndrome. Studies were searched in PubMed and Web of Science from 11 November to 30 November 2018. Eighteen studies were finally included based on inclusion and exclusion criteria. The relationship between SHS and the risk indicators of metabolic syndrome was analyzed. The weighted mean difference (WMD) of fasting plasma glucose (FPG), insulin, body mass index (BMI), and waist circumference (WC), and the standard mean difference (SMD) of total cholesterol, triglycerides, and low- and high-density lipoprotein-cholesterol (LDL-C, HDL-C) were calculated in a meta-analysis. SHS was positively associated with the level of insulin and WC. According to the subgroup analysis based on age difference, SHS was positively associated with FPG in the upper age group, and positively associated with LDL-C and negatively associated with HDL-C in the lower age group. BMI showed a more obvious positive correlation in the adults group than in the children and the teenagers group. In conclusion, the association of metabolic syndrome with SHS varies with age. When exposed to SHS, older people may be more susceptible to glucose metabolic disorder, but younger people may be more susceptible to lipid metabolic disorder.


Asunto(s)
Envejecimiento/metabolismo , Síndrome Metabólico/epidemiología , Contaminación por Humo de Tabaco/efectos adversos , Adolescente , Adulto , Factores de Edad , Glucemia/análisis , Índice de Masa Corporal , Niño , HDL-Colesterol/sangre , Humanos , Insulina/sangre , Resistencia a la Insulina , Metabolismo de los Lípidos , Síndrome Metabólico/sangre , Síndrome Metabólico/etiología , Obesidad/sangre , Obesidad Abdominal/etiología , Factores de Riesgo , Triglicéridos/sangre , Circunferencia de la Cintura
6.
Toxicol Lett ; 283: 91-99, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29155039

RESUMEN

Maternal nicotine (NIC) exposure causes overweight, hyperleptinemia and metabolic disorders in adult offspring. Our study aims to explore the underlying mechanism of perinatal NIC exposure increases obesity susceptibility in adult female rat offspring. In our model, we found that adult NIC-exposed females presented higher body weight and subcutaneous and visceral fat mass, as well as larger adipocytes, while no change was found in food intake. Serum profile showed a higher serum glucose, insulin and leptin levels in NIC-exposed females. In adipose tissue and liver, the leptin signaling pathway was blocked at 26 weeks, presented lower Janus tyrosine kinase 2 and signal transducer and activator of transcription 3 gene expression, higher suppressor of cytokine signaling 3 gene expression (in adipose tissue) and lower leptin receptors gene expression (in liver), indicating that peripheral leptin resistance occurred in NIC-exposed adult females. In female rats, the expression of lipolysis genes was affected dominantly in adipose tissue, but lipogenesis genes was affected in liver. Furthermore, the glucose and insulin tolerance tests showed a delayed glucose clearance and a higher area under the curve in NIC-exposed females. Therefore, perinatal NIC exposure programed female rats for adipocyte hypertrophy and obesity in adult life, through the leptin resistance in peripheral tissue.


Asunto(s)
Leptina/metabolismo , Nicotina/toxicidad , Agonistas Nicotínicos/toxicidad , Obesidad/inducido químicamente , Obesidad/metabolismo , Adipocitos/efectos de los fármacos , Adipocitos/ultraestructura , Animales , Animales Recién Nacidos , Peso Corporal/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Femenino , Expresión Génica/efectos de los fármacos , Grasa Intraabdominal/efectos de los fármacos , Lipólisis/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Embarazo , Ratas , Ratas Wistar
7.
Clin Nutr ; 37(5): 1462-1473, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28830700

RESUMEN

BACKGROUND & AIMS: The effect of maternal omega-3 fatty acids intake on the body composition of the offspring is unclear. The aim of this study was to conduct a systematic review and meta-analysis to confirm the effects of omega-3 fatty acids supplementation during pregnancy and/or lactation on body weight, body length, body mass index (BMI), waist circumference, fat mass and sum of skinfold thicknesses of offspring. METHODS: Human intervention studies were selected by a systematic search of PubMed, Web of Science, the Cochrane Library and references of related reviews and studies. Randomized controlled trials of maternal omega-3 fatty acids intake during pregnancy or lactation for offspring's growth were included. The data were analyzed with RevMan 5.3 and Stata 12.0. Effect sizes were presented as weighted mean differences (WMD) or standardized mean difference (SMD) with 95% confidence intervals (95% CI). RESULTS: Twenty-six studies comprising 10,970 participants were included. Significant increases were found in birth weight (WMD = 42.55 g, 95% CI: 21.25, 63.85) and waist circumference (WMD = 0.35 cm, 95% CI: 0.04, 0.67) in the omega-3 fatty acids group. There were no effects on birth length (WMD = 0.09 cm, 95% CI: -0.03, 0.21), postnatal length (WMD = 0.13 cm, 95% CI: -0.11, 0.36), postnatal weight (WMD = 0.04 kg, 95% CI: -0.07, 0.14), BMI (WMD = 0.09, 95% CI: -0.05, 0.23), the sum of skinfold thicknesses (WMD = 0.45 mm, 95% CI: -0.30, 1.20), fat mass (WMD = 0.05 kg, 95% CI: -0.01, 0.11) and the percentage of body fat (WMD = 0.04%, 95% CI: -0.38, 0.46). CONCLUSIONS: This meta-analysis showed that maternal omega-3 fatty acids supplementation can increase offspring's birth weight and postnatal waist circumference. However, it did not appear to influence children's birth length, postnatal weight/length, BMI, sum of skinfold thicknesses, fat mass and the percentage of body fat during postnatal period. Larger, well-designed studies are recommended to confirm this conclusion.


Asunto(s)
Composición Corporal/fisiología , Ácidos Grasos Omega-3/farmacología , Fenómenos Fisiologicos de la Nutrición Prenatal/fisiología , Peso al Nacer , Composición Corporal/efectos de los fármacos , Estatura , Índice de Masa Corporal , Lactancia Materna , Suplementos Dietéticos , Ácidos Grasos Omega-3/administración & dosificación , Femenino , Humanos , Recién Nacido , Lactancia , Masculino , Madres , Embarazo , Fenómenos Fisiologicos de la Nutrición Prenatal/efectos de los fármacos , Grosor de los Pliegues Cutáneos
8.
Acta Pharmacol Sin ; 39(1): 140-153, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28880015

RESUMEN

In order to develop an integrated pharmacokinetic/viral dynamic (PK/VD) model to predict long-term virological response rates to daclatasvir (DCV) and asunaprevir (ASV) combination therapy in patients infected with genotype 1 (GT1) chronic hepatitis C virus (HCV), a systematic publication search was conducted for DCV and ASV administered alone and/or in combination in healthy subjects or patients with GT1 HCV infection. On the basis of a constructed meta-database, an integrated PK/VD model was developed, which adequately described both DCV and ASV PK profiles and viral load time curves. The IC50 values of DCV and ASV were estimated to be 0.041 and 2.45 µg/L, respectively, in GT1A patients. A sigmoid Emax function was applied to describe the antiviral effects of DCV and ASV, depending on the drug concentrations in the effect compartment. An empirical exponential function revealed that IC50 changing over time described drug resistance in HCV GT1A patients during DCV or ASV monotherapy. Finally, the PK/VD model was evaluated externally by comparing the expected and observed virological response rates during and post-treatment with DCV and ASV combination therapy in HCV GT1B patients. Both the rates were in general agreement. Our PK/VD model provides a useful platform for the characterization of pharmacokinetic/pharmacodynamic relationships and the prediction of long-term virological response rates to aid future development of direct acting antiviral drugs.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Imidazoles/uso terapéutico , Isoquinolinas/uso terapéutico , Modelos Biológicos , Sulfonamidas/uso terapéutico , Adulto , Anciano , Antivirales/farmacocinética , Carbamatos , Simulación por Computador , Quimioterapia Combinada , Femenino , Genotipo , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Hepatitis C Crónica/genética , Humanos , Imidazoles/farmacocinética , Isoquinolinas/farmacocinética , Masculino , Persona de Mediana Edad , Pirrolidinas , Sulfonamidas/farmacocinética , Valina/análogos & derivados , Carga Viral
9.
Acta Pharmacol Sin ; 33(10): 1311-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22941289

RESUMEN

AIM: To elucidate the roles of receptor tyrosine kinases RET and VEGFR2 and the RAF/MEK/ERK signaling cascade in cancer treatment with sorafenib. METHODS: The cell lines A549, HeLa, and HepG2 were tested. The enzyme activity was examined under cell-free conditions using 384-well microplate assays. Cell proliferation was evaluated using the Invitrogen Alarmar Blue assay. Gene expression was analyzed using the Invitrogen SYBR Green expression assays with a sequence detection system. Protein expression analysis was performed using Western blotting. RESULTS: Sorafenib potently suppressed the activities of cRAF, VEGFR2, and RET with IC(50) values of 20.9, 4 and 0.4 nmol/L, respectively. Sorafenib inhibited cRAF, VEGFR2, and RET via non-ATP-competitive, ATP-competitive and mixed-type modes, respectively. In contrast, sorafenib exerted only moderate cytotoxic effects on the proliferation of the 3 cell lines. The IC(50) values for inhibition of A549, HeLa, and HepG2 cells were 8572, 4163, and 8338 nmol/L, respectively. In the 3 cell lines, sorafenib suppressed the cell proliferation mainly by blocking the MEK/ERK downstream pathway at the posttranscriptional level, which in turn regulated related gene expression via a feed-back mechanism. CONCLUSION: This study provides novel evidence that protein kinases RET and VEGFR2 play crucial roles in cancer treatment with sorafenib.


Asunto(s)
Antineoplásicos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/farmacología , Proteínas Proto-Oncogénicas c-ret/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Antineoplásicos/uso terapéutico , Western Blotting , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/genética , Neoplasias/enzimología , Neoplasias/patología , Niacinamida/farmacología , Niacinamida/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Proteínas Proto-Oncogénicas c-ret/genética , Interferencia de ARN/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Sorafenib , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
10.
Br J Clin Pharmacol ; 73(5): 706-16, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22044402

RESUMEN

UNLABELLED: AIMS To evaluate the pharmacology and tolerability of PF-04457845, an orally available fatty acid amide hydrolase-1 (FAAH1) inhibitor, in healthy subjects. METHODS: Double-blind, randomized, placebo-controlled single and multiple rising dose studies and an open-label, randomized, food effect study were conducted. Plasma and urine PF-04457845 concentrations, plasma fatty acid amide concentrations and FAAH1 activity in human leucocytes were measured. Tolerability, including effects on cognitive function, were assessed. RESULTS: PF-04457845 was rapidly absorbed (median t(max) 0.5-1.2 h). Exposure increased supraproportionally to dose from 0.1 to 10 mg and proportionally between 10 and 40 mg single doses. The pharmacokinetics appeared dose proportional following 14 days once daily dosing between 0.5 and 8 mg. Steady-state was achieved by day 7. Less than 0.1% of the dose was excreted in urine. Food had no effect on PF-04457845 pharmacokinetics. FAAH1 activity was almost completely inhibited (>97%) following doses of at least 0.3 mg (single dose) and 0.5 mg once daily (multiple dose) PF-04457845. Mean fatty acid amide concentrations increased (3.5- to 10-fold) to a plateau and then were maintained following PF-04457845. FAAH1 activity and fatty acid amide concentrations returned to baseline within 2 weeks following cessation of dosing at doses up to 4 mg. There was no evidence of effects of PF-04457845 on cognitive function. PF-04457845, at doses up to 40 mg single dose and 8 mg once daily for 14 days, was well tolerated. CONCLUSIONS: PF-04457845 was well tolerated at doses exceeding those required for maximal inhibition of FAAH1 activity and elevation of fatty acid amides.


Asunto(s)
Amidohidrolasas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Piridazinas/farmacología , Urea/análogos & derivados , Adulto , Amidohidrolasas/metabolismo , Análisis de Varianza , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Inhibidores Enzimáticos/efectos adversos , Inhibidores Enzimáticos/farmacocinética , Humanos , Masculino , Persona de Mediana Edad , Piridazinas/efectos adversos , Piridazinas/farmacocinética , Urea/efectos adversos , Urea/farmacocinética , Urea/farmacología , Adulto Joven
11.
World J Gastroenterol ; 16(17): 2170-5, 2010 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-20440859

RESUMEN

AIM: To investigate the association between peroxisome proliferator-activated receptor-gamma (PPAR-gamma) gene polymorphism 34 C>G and colorectal cancer (CRC), a meta-analysis review was performed in this report. METHODS: A systematic literature search and selection of eligible relevant studies were carried out. Nine independent studies with a total number of 4533 cases and 6483 controls were included in the meta-analysis on the association between polymorphism 34 C>G and CRC. RESULTS: There was no evidence for the association between PPAR-gamma 34 C>G and CRC if all of the subjects in the nine studies were included. However, CG + GG showed a marginally significant difference from CC (OR = 0.84, 95% CI: 0.69-1.01, P = 0.07) in random-effect model. Stratified meta-analysis indicated that PPAR-gamma 34 C>G was associated with colon cancer (OR = 0.8, 95% CI: 0.65-0.99, P = 0.04) in random-effect model, and the G allele decreased colon cancer risk. No significant association was observed between PPAR-gamma 34 C>G and rectal cancer. CONCLUSION: PPAR-gamma 34 C>G is associated with colon cancer risk, but not associated with CRC and rectal cancer risk.


Asunto(s)
Neoplasias Colorrectales/genética , PPAR gamma/genética , Factores de Riesgo , Alelos , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Humanos , Modelos Genéticos , Polimorfismo de Nucleótido Simple
12.
Pharm Res ; 21(5): 844-50, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15180344

RESUMEN

PURPOSE: The aim of this study was to characterize the influence of pH and NaCl concentration on the transdermal iontophoretic transport of the dopamine receptor agonist rotigotine across human stratum corneum (HSC). METHODS: Rotigotine transport was studied in vitro in side by side diffusion cells according to the following protocol: 6 h of passive diffusion, 9 h of iontophoresis, and 5 h of passive diffusion. A current density of 0.5 mA cm(-2) was used. The influence of donor phase pH (4, 5, and 6) and different concentrations of NaCl (0.07 and 0.14 M) on rotigotine iontophoretic flux were examined. The acceptor phase was phosphate-buffered saline (PBS) at pH 7.4 except in one series of experiments aimed to study the effects of rotigotine solubility on its iontophoretic transport. In this study, PBS at pH 6.2 was used. In separate studies. 14C-mannitol was used as a marker to determine the role of electro-osmosis during iontophoresis. RESULTS: The estimated iontophoretic steady-state flux (Flux(ss)) of rotigotine was influenced by the pH of the donor solution. At a drug donor concentration of 0.5 mg ml(-1), the iontophoretic flux was 30.0 +/- 4.2 nmol cm(-2) h(-1) at pH 6 vs. 22.7 +/- 5.5 nmol cm(-2) h(-1) at pH 5. However, when the donor concentration was increased to 1.4 mg ml(-1), no significant difference in iontophoretic rotigotine transport was observed between pH 5 and 6. Increase of NaCl concentration from 0.07 M to 0.14 M resulted in a decrease of the rotigotine Flux(ss) from 22.7 +/- 5.5 nmol cm(-2) h(-1) to 14.1 +/- 4.9 nmol cm(-2) h(-1). The contribution of electro-osmosis was estimated less than 17%. Probably due to the lipophilic character of the drug, impeding the partitioning of rotigotine from HSC to the acceptor compartment, steady-state transport was not achieved during 9 h of iontophoresis. CONCLUSIONS: Both pH and NaCl concentration of the donor phase are crucial on the iontophoretic transport of rotigotine. Electro-repulsion is the main mechanism of the iontophoretic transport of rotigotine.


Asunto(s)
Antiparkinsonianos/administración & dosificación , Agonistas de Dopamina/administración & dosificación , Agonistas de Dopamina/farmacocinética , Absorción Cutánea/fisiología , Tetrahidronaftalenos/administración & dosificación , Tiofenos/administración & dosificación , Administración Cutánea , Algoritmos , Antiparkinsonianos/farmacocinética , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Iontoforesis , Cinética , Ósmosis , Cloruro de Sodio/farmacología , Solubilidad , Tetrahidronaftalenos/farmacocinética , Tiofenos/farmacocinética
13.
Int J Pharm ; 266(1-2): 61-8, 2003 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-14559394

RESUMEN

To validate the efficacy and controllability of a newly developed transdermal delivery system for R-apomorphine in combination with the surfactant pretreatment, iontophoresis was performed in three-chamber continuous-flow-through diffusion cells in vitro. The transdermal iontophoretic transport of R-apomorphine was examined with both human SC and freshly dermatomed human skin, at room temperature and at 32 degrees C. Furthermore, the relationship between current density and iontophoretic flux was investigated. By increasing the temperature from 22 to 32 degrees C, the iontophoretic transport rate of R-apomorphine in human SC was increased 1.9-fold. Also the iontophoretic flux increased linearly with the increase in the current density from 100 to 500 microA/cm(2). When using dermatomed human skin instead of SC, the iontophoretic flux at a current density of 500 microA/cm(2) was decreased from 362+/-45 to 259+/-30 nmol/cm(2)h, and the corresponding lag time was prolonged from 0.8 to 2.8h. In conclusion, the combination of non-occlusive pretreatment with the surfactant formulation and iontophoresis has shown to substantially increase the transdermal transport rate of R-apomorphine. A linear relationship between current density and R-apomorphine flux indicates that the iontophoretic delivery combined with surfactant pretreatment allows a controlled and individualised administration of R-apomorphine.


Asunto(s)
Apomorfina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Iontoforesis/métodos , Tensoactivos/administración & dosificación , Apomorfina/farmacocinética , Combinación de Medicamentos , Humanos , Técnicas In Vitro , Piel/efectos de los fármacos , Piel/metabolismo , Estereoisomerismo , Tensoactivos/farmacocinética
14.
Pharm Res ; 20(4): 653-9, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12739775

RESUMEN

PURPOSE: To further increase the transdermal transport rate of R-apomorphine, a nonocclusive pretreatment with an aqueous surfactant formulation in combination with iontophoresis was explored in vitro. METHODS: The human stratum corneum was pretreated nonocclusively with formulations composed of laureth-3 oxyethylene ether (C12EO3), laureth-7 oxyethylene ether (C12EO7), and cholesterol sulfate (CSO4) prior to iontophoresis. The effect on the flux of the following parameters was examined: the composition, the charge, and the applied amount of surfactant formulations. RESULTS: The iontophoretic flux of R-apomorphine was appreciably increased by pretreatment with surfactant formulations. A formulation containing C12EO3/C12EO7/CSO4 at a molar ratio of 70:30:5 was very stable and increased the iontophoretic flux of R-apomorphine from 92.2 +/- 13.9 nmol/cm2 x h to 181.5 +/- 22.6 nmol/cm2 x h. When further increasing the negative charge of this formulation the iontophoretic transport rate was slightly inhibited. A dose of 40 microL/cm2 of the formulation with a total surfactant concentration of 5% (w/w) was sufficient for a maximum enhancing effect. CONCLUSIONS: The results obviously show that nonocclusive pretreatment with the surfactant formulation enhances the iontophoretic transport of R-apomorphine, and is a promising approach to achieve therapeutic concentrations of R-apomorphine.


Asunto(s)
Administración Cutánea , Apomorfina/administración & dosificación , Apomorfina/farmacocinética , Preparaciones de Acción Retardada , Sistemas de Liberación de Medicamentos , Iontoforesis/métodos , Enfermedad de Parkinson/tratamiento farmacológico , Polietilenglicoles/farmacocinética , Absorción Cutánea/efectos de los fármacos , Tensoactivos/farmacocinética , Adyuvantes Farmacéuticos/administración & dosificación , Adyuvantes Farmacéuticos/farmacocinética , Técnicas In Vitro , Soluciones Farmacéuticas/farmacocinética , Polidocanol , Absorción Cutánea/fisiología , Tensoactivos/química
15.
J Control Release ; 84(1-2): 49-57, 2002 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-12399167

RESUMEN

To achieve a therapeutical effect of the anti-Parkinson's drug R-apomorphine via iontophoresis delivery, enhancement strategies in vitro were explored using three structurally related enhancers, lauric acid (LA), dodecyltrimethylammonium bromide (DTAB) and Laureth-3 oxyethylene ether (C(12)EO(3)). Human stratum corneum and shed snake skin were pretreated with 0.15 M each enhancer solution in propylene glycol (PG). Thereafter, passive diffusion, iontophoretic transport and post-iontophoretic passive diffusion were investigated. Compared to the control (PG pretreatment), a slight inhibition on both passive and iontophoretic delivery was observed with cationic surfactant DTAB pretreated stratum corneum. Pretreatment with anionic surfactant LA resulted in a great enhancement on passive delivery, but only a small enhancing effect on the iontophoretic delivery. Unlike the others, the nonionic surfactant C(12)EO(3) substantially increased iontophoretic transport rate of R-apomorphine by 2.3-fold, whereas passive delivery was basically unchanged or slightly affected. The magnitude of enhancing effect of C(12)EO(3) was dependent on the surfactant concentration and the pretreatment duration. Moreover, comparison of transport data through shed snake skin with human stratum corneum indicates that both shunt- and intercellular pathways are involved in the iontophoretic transport of R-apomorphine.


Asunto(s)
Apomorfina/administración & dosificación , Apomorfina/farmacocinética , Agonistas de Dopamina/administración & dosificación , Agonistas de Dopamina/farmacocinética , Animales , Apomorfina/química , Cromatografía Líquida de Alta Presión , Cámaras de Difusión de Cultivos , Agonistas de Dopamina/química , Humanos , Técnicas In Vitro , Iontoforesis , Absorción Cutánea , Serpientes , Estereoisomerismo , Estimulación Química , Relación Estructura-Actividad
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