ABSTRACT
OBJECTIVE To prepare Neuritic acid oral emulsion ，to optimize its formulation and preparation technology ，and to investigate its stability. METHODS Neuritic acid oral emulsion was prepared by mechanical method. On the basis of single factor experiment ，the appearance ，centrifugal stability ，centrifugal stability constant （Ke）and particle size of the emulsion as indexes，the formulation was optimized by orthogonal design ，taking the dosage of oleic acid ，octylphenol polyoxyethylene ether-10 and propylene glycol as factors ，the preparation technology was optimized by taking emulsification temperature ，shear time，pressure of high-pressure homogenization and cycle times of high-pressure homogenization as factors. The content of neuritic acid was determined by high performance liquid chromatography. The stability of Neuritic acid oral emulsion was investigated by high temperature test ，accelerated test and long-term test. RESULTS The optimal formulation and preparation technology were as follows：neuritic acid of 1 g，oleic acid of 5％ ，octylphenol polyoxyethylene ether- 10 of 4％ ，propylene glycol of 2％ ， emulsification temperature of 60 ℃ ，shear time of 2 min，homogenization pressure of 40 MPa and cycle times of twice. After three experiments ，the average particle size of Neuritic acid oral emulsion was 158.05 nm（RSD＝1.58％，n＝3），the average Ke was 0.39（RSD＝1.49％，n＝3），and the appearance was uniform milky white ，there was no stratification. The results of high temperature test showed that Neuritic acid oral emulsion was prone to stratification in high temperature environment ，and the content of neuritic acid increased. The results of accelerated test and long-term test showed that there was no significant change in the appearance or the content of neuritic acid when Neuritic acid oral emulsion was placed at room temperature for 6 months. CONCLUSIONS The formulation and preparation technology are stable and feasible ，and can be used for the preparation of Neuritic acid oral emulsion. Neuritic acid oral emulsion should not be placed in high temperature environment. It has good stability at room temperature for 6 months.
ABSTRACT
This study is to report the establishment of an UPLC-MS/MS method for the determination of plasma concentration of UA carried in self-microemulsifying drug delivery system (SMEDDS) and its pharmacokinetics in rats. It was used for determination and analysis when serum with internal standard was extracted from C18 solid-phase column. Acquity UPLC BEH C18 column (100 mm x 2.1 mm, 1.7 microm) was used for separation. The mobile phase was acetonitrile -0.1% ammonia with gradient elution at the flow rate of 0.2 mL x min(-1). The column temperature was 40 degrees C and the detection wave length was 210 nm. It was detected by negative ion using electrospray ionization source (ESI) and scanned by multiple reaction ion monitoring (MRM) mode. The liner relationship of UA was very good in the range of 1.19-3 815.00 ng x mL(-1) (r = 0.999 0). Recovery rate of different concentrations were 87.42%-89.95%. The precision of inter-day and intra-day were less than 11%. The method developed in our study was proved to be sensitive, rapid and simple. It is suitable for the pharmacokinetic study of UA-SMEDDS in rats.
ABSTRACT
<p><b>OBJECTIVE</b>To observe the injury in rat primary cultured neurons induced by Abeta(1-40) and the protective effects of combination of ginseng and ginko extracts.</p><p><b>METHOD</b>Primary neurons were induced by Abeta(1-40) to establish the cell model of toxic injury. Using flow cytometry with Annexin V-FITC/PI double staining, MTP assay, transmission electron microscopy and Western blot, the appropriate concentration and duration of AP for cell model establishment were determined. The effects of extracts of ginseng and ginko (EGGB)on cellular proliferative activity, apoptotic rate, ultrastructure and caspase-3 expression were detected.</p><p><b>RESULT</b>The apoptotic rate was increased significantly after neurons were induced by 1 micromol x L(-1) Abeta(-40) for 24 h (P < 0.01). EGGB (5, 50 mg L(-1)) significantly enhanced the proliferative activity (P < 0.05). Meanwhile, EGGB (50 mg L(-1)) inhibited neuronal apoptosis and caspase-3 overexpression and improved cellular ultrastructure remarkably (P < 0.05, P < 0.01).</p><p><b>CONCLUSION</b>Abeta(1-40) could significantly induce primary cultured neurons to apoptosis in vitro. EGGB showed beneficial neuroprotective effects against neuronal apoptosis, which might be due to improving the structures of neuron and its subcellular organelles, enhancing cellular proliferative activity and inhibiting caspase-3 overexpression in neurons.</p>