Preparation of aminophylline patches and their pharmacokinetics in rabbits after navel adminstration / 中国药学杂志

OBJECTIVE: To prepare aminophylline patches and study the pharmacokinetic characteristics in rabbits after application on navel. METHODS: Aminophylline patches were prepared by hot-envelop method. Modified Franz diffusion cells were employed to screen permeation enhancers with excised rat abdomen skins as diffusion barrier. The concentration of aminophylline in rabbit plasma was determined by HPLC after aminophylline solution was irrigated intragastrically and the aminophylline patches were applied on notum and navel, respectively. Pharmacokinetic parameters were calculated and the pharmacokinetic profiles were characterized by comparing the above three groups with statistical analysis. RESULTS: Based on the excised rat skin permeation test, 3% menthol-propanediol (1: 1) mixture was the optimal permeation enhancer with a steady state permeation rate of (9.08 ± 0.21) μg · cm-2 · h-1. The main pharmacokinetic parameters of, notum application group and navel application group were as follows: ρmax were (13.42 ± 1.10), (4.53 ± 0.39) and (5.77 ± 0.44) μg · mL-1 and tmax(1.83 ± 0.29), (5.67 ± 0.58) and (4.33 ± 0.58) h, AUC0→t, (47.65 ± 3.46), (31.65 ± 4.11) and (39.97 ± 3.14) μg · h · mL-1, t1/2 (1. 90 ± 0.30), (2.45 ± 0.07) and (1.90 ± 0.06) h, Ka(2.01 ± 0.55), (0.33 ± 0.02) and (0.55 ± 0.04) h-1, tlag were (0.19 ± 0.04), (0.59 ± 0.03) and (0.32 ± 0.19) h, respectively. The relative bioavailabilities of aminophylline after notum and navel application were (67.41 ± 19.11)% and (84.81 ± 18.03)% respectively compared with intragastrical irrigation group. CONCLUSION: The preparation process of aminophylline patches with desirable skin permeation property is practicable. Aminophylline patches are able to realize sustained-drug release and have higher bioavailability after navel application compared with notum application.

Transcriptional activation of insulin-like growth factor binding protein 6 by 17beta-estradiol in SaOS-2 cells

Osteoblasts can synthesize the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs), which may either enhance or attenuate IGF-stimulated bone cell proliferation. Since estrogen induced osteoblastic differentiation and proliferation through an estrogen-responsive gene in target cells, we investigated the effects of estrogen on IGFBP-6 expression in the human osteoblastic-like cell line SaOS-2. Expressions of IGFBP-6 protein and mRNA increased 2.8 and 2-fold, respectively, in the presence of 17-beta-estradiol (E2) (0.01 to 1 micrometer) and estrogen receptor (ER) in SaOS-2 cells. On the other hand, E2 induced a 2-fold increase in SaOS-2 cell proliferation. To identify genomic sequences associated with estrogen responsiveness, the 5'-promoter region (-44 to +118) of the IGFBP-6 gene was cloned into a chloramphenicol acetyltransferase (CAT) reporter vector. E2 induced a 3-fold increase in CAT activity in SaOS-2 cells transiently transfected with this construct. Identification of the estrogen-responsive element (ERE) [5'-CCTTCA CCTG-3'] (-9 to +1) in this IGFBP-6 gene promoter region was confirmed using electromobility shift assays and deletion analysis. This functional ERE was important for E2-induced trans-activation of the IGFBP-6 gene. These results demonstrate that E2 exhibits a positive effect on IGFBP-6 gene transcription through estrogen-liganded ER binding to the functional ERE in the IGFBP-6 gene promoter in SaOS-2 cells.

Effect of dioxin on apoptosis of osteogenic sarcoma cells and regulation on gene expression of insulin-like growth factor binding protein 6 / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effect of the environmental carcinogenic factor-TCDD (2, 3, 7, 8-tetrachlorodibenzo-p-dioxin) on cell apoptosis and gene regulation of insulin-like growth factor binding protein 6 (IGFBP-6) in osteogenic sarcoma (SaOS-2) cells.</p><p><b>METHODS</b>The SaOS-2 cells were cultured with TCDD (1 x 10(-9), 1 x 10(-8), 1 x 10(-7) mol/L) for 24 hours. The MTT reduction assay and flow cytometry were used to measure the cell proliferation and the cell apoptosis in TCDD-treated SaOS-2 cells. The Nitrophenol phosphate salt method was used to measure activity of alkaline phosphatase (ALP) in SaOS-2 cells. The IGFBP-6 mRNA and protein in SaOS-2 cells were detected by reverse transcription polymerase chain reaction (RT-PCR) and western blotting analysis.</p><p><b>RESULTS</b>SaOS-2 cell proliferation was up-regulated with TCDD (1 x 10(-9), 1 x 10(-8), and 1 x 10(-7) mol/L) about 20%, 47% and 93% (18.4 +/- 4.5, 22.5 +/- 3.6 and 29.4 +/- 4.2), respectively. The synthesis of ALP was up-regulated about 28%, 95%, and 142% (1.12 +/- 0.28, 1.58 +/- 0.14 and 1.96 +/- 0.17), respectively (P < 0.05). The cell apoptosis was down-regulated in dose-dependent biological manner about 5%, 26% and 52%, respectively (P < 0.05). The expression of IGFBP-6 mRNA and protein was decreased in 1 x 10(-7) mol/L TCDD-treated SaOS-2 cells about 76% and 72% (P < 0.05).</p><p><b>CONCLUSION</b>TCDD at low concentration may have the negative effect on cell apoptosis and down-regulation on gene expression of IGFBP-6 in SaOS-2 cells.</p>

Retinoic acid down-regulates bone morphogenetic protein 7 expression in rat with cleft palate / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To evaluate the effects of retinoic acid (RA) on expression of bone morphogenetic protein 7 (BMP-7) in rat fetus with cleft palate, and the effects of RA on proliferation and apoptosis of osteoblasts.</p><p><b>METHODS</b>All-trans RA (ATRA) was used to induce congenital cleft palate in Wistar rat BMP-7 mRNA expression in maxillary bone tissue of fetal rats was measured by Northern blotting analysis. Flow cytometry and MTT assay were used to measure the apoptosis and proliferation of ATRA-treated MC-3T3-E1 cells. BMP-7 mRNA and protein expressions in ATRA-treated MC-3T3-E1 cells were detected by RT-PCR and Western blotting analysis.</p><p><b>RESULTS</b>ATRA could induce cleft palate of rat fetus. The incidence rate of cleft palate induced by 100 mg/kg AT-RA (45.5%) was significantly higher than 50 mg/kg ATRA (12.5%, P < 0.05). BMP-7 mRNA expression decreased in maxillary bone tissue of rat fetus with cleft palate. MC-3T3-E1 cells proliferation treated with 1 x 10(-6) mol/L ATRA decreased by 60%, the cell apoptosis increased by 2 times. BMP-7 mRNA and protein levels in MC-3T3-E1 cells treated with 1 x 10(-6) mol/L ATRA decreased by 60% and 80%, respectively, compared with ATRA-untreated cells (P < 0.05).</p><p><b>CONCLUSIONS</b>BMP-7 may play an important role in embryonic palate development RA may possess the ability to down-regulate cell proliferation through regulation of BMP-7 gene expression.</p>

HLA-DQB1 allele polymorphism and clinical characteristics of 15 familial myasthenia gravis cases in north China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the HLA-DQB1 allele polymorphisms and the clinical features of 15 familial myasthenia gravis (MG) cases in north China.</p><p><b>METHODS</b>By polymerase chain reaction-sequence specific primers (PCR-SSP), the HLA-DQB1 gene polymorphisms were determined in 64 MG patients (15 familial and 49 sporadic) and 52 healthy individuals as control group. The clinical characteristics of 15 familial MG patients and 49 sporadic were analyzed. The measurement data was analyzed by t test and enumeration data by chi-square test.</p><p><b>RESULTS</b>The frequency of DQB1*0501 was significantly increased in familial MG, especially in the ocular type, compared with sporadic MG (P<0.05, OR=3.08) and healthy controls (P<0.01, OR=4.439). Comparing with healthy controls, the frequency of DQB1*0301/4 was increased (P<0.05, OR=2.56), while the frequency of DQB1*0601 was significantly decreased (P<0.05, OR=0.33) in sporadic MG. The familial patients had an early age of disease onset, but less severity and good prognosis.</p><p><b>CONCLUSION</b>The familial MG has distinctive clinical features. DQB1*0501 allele is positively related to the genetic susceptibility to familial MG patients in north China, especially to the ocular type. DQB1*0301/4 allele is positively related to the pathogenesis of sporadic MG. DQB1*0601 may be a protecting allele for sporadic MG. The phenotype of MG may be the result of interaction of hereditary defects and environmental factors. The familial MG may be different from sporadic patients in genetic immune mechanism.</p>