[Optimization of the extraction process of the effective components in fructus phyllanthi].

OBJECTIVE: To optimize the extraction process of the effective components in Fructus Phyllanthi. METHODS: Using Fructus Phyllanthi from Puning, Guangdong as the raw materials, its extraction process was screened by the orthogonal design. The extraction rates of polyphenol from Fructus Phyllanthi under different extraction conditions were compared to determine the optimum extraction technology. The effects of the ratio of raw materials to liquid, extraction time, extraction temperature and extraction number on extraction rates of polysaccharose in Fructus Phyllanthi were also investigated. RESULTS: The optimum extraction conditions for polyphenol were as follows: 50% methanol as solvent, ratio of raw materials to liquid 1:10, extraction times 1, extraction time 90 min. The optimum extracting conditions for polysaccharose were as follows: ratio of raw materials to liquid 1:20, extraction time 3.0 h, extraction times 3, and extraction temperature 90 degrees C. CONCLUSION: The optimization of the extraction process for polyphenol and polysaccharide in Fructus Phyllanthi has a good reference guide for further developing a seris of health care products of Fructus Phyllanthi.

Inhibition of SNAP-25 phosphorylation at Ser187 is involved in chronic morphine-induced down-regulation of SNARE complex formation.

Opiate abuse has been shown to cause adaptive changes in presynaptic release and protein phosphorylation-mediated synaptic plasticity, but the underlying mechanisms remain unclear. Neuronal SNARE proteins serve as important regulatory molecules underlying neural plasticity in view of their major role in the process of neurotransmitter release. In the present study, the expression of SNAP-25, a t-SNARE protein essential for vesicle release, was found to be dramatically regulated in hippocampus after chronic morphine treatment, which was visualized with two-dimensional gel electrophoresis. The spots of SNAP-25 in the gel were shifted along the dimension of isoelectric point, indicating a likely change of the post-transcriptional modification. Immunoblotting analysis with specific antibody to Ser187, a protein kinase C (PKC) phosphorylation site of SNAP-25, revealed that the specific phosphorylation was correspondingly decreased, which was correlated with morphine-induced inhibition of PKC activity. Moreover, the level of ternary complex of SNARE proteins in either synaptosomes or PC12 cells was significantly reduced after chronic morphine treatment. This suggests a causal relationship between the inhibition of PKC-dependent SNAP-25 phosphorylation and the down-regulation of SNARE complex formation after chronic morphine treatment. Further analysis of SNARE complex formed by transfection of the wild-type or Ser187 mutants of SNAP-25 showed that only wild-type-formed complex was inhibited by morphine treatment. Thus, these results indicate that chronic morphine treatment inhibits phosphorylation of SNAP-25 at Ser187 and leads to a down-regulation of SNARE complex formation, which presents a potential molecular mechanism for the alteration of exocytotic process and neural plasticity during opiate abuse.