Résumé
Objective:To observe the effect of tetrahydroxy stilbene glycoside (TSG) on the expression of glycogen synthase kinase 3<italic>β </italic>(GSK3<italic>β</italic>), cyclic adenosine monophosphate-dependent protein kinase (PKA) and Serine/threonine phosphatase 2A(PP2A) in the brain of amyloid precursor protein/presenilin-1/Tau (APP/PS1/Tau) triple-transgenic mice dementia model. Method:A total of forty-five 8-month-old APP/PS1/Tau transgenic mice were randomly divided into model group, positive control group (Huperzine-A, 0.15 mg·kg<sup>-1</sup>), low, medium and high dose TSG groups (TSG, 0.033,0.1,0.3 g·kg<sup>-1</sup>), with 9 mice in each group, and another nine C5B7L/6J mice of the same age were selected as normal control group. After 60 days of intragastric administration, the general structure of hippocampal neurons was observed by hematoxylin-eosin (HE) staining, immunohistochemical (IHC) was used to detect the expression of PKA protein in the brain of mice in each group, the mRNA expression levels of GSK3<italic>β</italic>, PKA and PP2A were detected by real time quantitative reverse transcription polymerase chain reaction (Real-time PCR), and protein expression levels of GSK3<italic>β</italic> and PP2A were detected by Western blot. Result:Compared with the normal control group, the apoptosis level of neurons in the model group was significantly increased, the protein and mRNA expression levels of GSK3<italic>β</italic> and PKA were significantly increased (<italic>P</italic><0.05, <italic>P</italic><0.01), and the protein and mRNA expression levels of PP2A were significantly decreased (<italic>P</italic><0.05, <italic>P</italic><0.01). Compared with the model group, the apoptosis level of neurons in each treatment group was significantly down-regulated, the protein and mRNA expression levels of GSK3<italic>β</italic> and PKA were significantly down-regulated (<italic>P</italic><0.05, <italic>P</italic><0.01), and the protein and mRNA expression levels of PP2A were significantly increased (<italic>P</italic><0.05, <italic>P</italic><0.01). Conclusion:The mechanism of TSG in the treatment of Alzheimer's disease (AD) may be related to lowering the transcription and expression of GSK3<italic>β</italic> and PKA, increasing the transcription and expression of PP2A.
Résumé
The authors designed to separate, purify and determine the monosaccharide composition of the polysaccharide from Cordyceps militaris, and study its effect on reverse cholesterol transport in vivo by isotope tracing assay. Polysaccharides were separate and purify by ion exchange column Q-sepharose Fast Flow and size exclusion column Sephacryl S200HR; the molecular weight and monosaccharide composition of the polysaccharides were determined by high performance gel permeation chromatography and high performance liquid chromatography coming with pre-column derivation, respectively. Finally, three purified polysaccharides CMBW1, CMBW2 and CMYW1 were obtained, their total carbohydrate contents were 87%, 89%, 95%, respectively; their protein contents were 6.5%, 1.3%, 2.8%, respectively; their molecular weights were 772.1, 20.9, 13.2 kDa, respectively; CMBW1 was composed of mannose, glucosamine, rhamnose, glucuronic acid, glucose, galactose and arabinose with a molar ratio of 7.25: 0.17: 1.29: 0.23: 6.30: 11.08: 0.79; CMBW2 was composed of mannose, glucosamine, galactose and arabinose with a molar ratio of 2.40: 0.16: 2.92: 0.24; CMYW1 was composed of mannose, glucosamine, glucuronic acid and glucose with a molar ratio of 0.59: 0.57: 0.45: 25.61. Polysaccharide at 50 mg x kg(-1) could significantly improve the transport of 3H- cholesterol to blood and excretion from feces. All of the three purified polysaccharides CMBW1, CMBW2 and CMYW1 were heteropolysaccharide; and they could improve reverse cholesterol transport in vivo, the underlying mechanisms are being studied.
Sujets)
Animaux , Souris , Transport biologique , Cholestérol , Métabolisme , Chromatographie en phase liquide à haute performance , Méthodes , Cordyceps , Chimie , Oses , Polyosides , Chimie , Pharmacologie , TritiumRésumé
In order to develop recombinant porcine Interferon-gamma (rPoIFN-gamma) to prevent porcine viral infection, PoIFN-gamma cDNA lacking the signal peptide was expressed in Pichia pastoris GS115 strain, and the effect of rPoIFN-gamma on porcine reproductive and respiratory syndrome virus (PRRSV) was investigated. The PoIFN-gamma gene was inserted into integrative vector pHIL-S1, and the recombinant GS115 strain (pHIL-S1/PoIFN-gamma) was constructed by homologues recombinant. The rPoIFN-gamma protein was 18 kD with an expressing yield of 18% was assayed by SDS-PAGE and Western blot, respectively. The anti-viral activity of rPoIFN-gamma was in the range of 450-540 u/mL. In addition, the effect of rPoIFN-gamma ant-PRRSV was determined using CPE50 method. The results indicated that high concentration of rPoIFN-gamma could inhibit PRRSV on Marc-145 cell line. The rPoIFN-gamma is a potential drug for prevention and treatment of various kinds of viral pig diseases.