Effect of EGCG on oxidative stress and Nrf2/HO-1 pathway in neurons exposed to oxygen-glucose deprivation/reperfusion / 中南大学学报(医学版)

To explore the effect of epigallocatechin gallate (EGCG) on oxidative stress and Nrf2/HO-1 pathway in neurons subjected to oxygen-glucose deprivation/reperfusion (OGD/R).
 Methods: Primary cultured cerebral cortical neurons were prepared from Sprague-Dawley rats, and the OGD/R cell model was established. After pretreatment with EGCG at different concentrations (12.5, 25.0, 50.0 or 100.0 μmol/L), the neurons were subjected to OGD/R. The cell viability, reactive oxygen species (ROS) level and malondialdehyde (MDA) content were assessed after reperfusion. The superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were measured. The expression of Nrf2 protein in nucleus, HO-1 mRNA and protein were detected.
 Results: OGD/R treatment reduced the cell viability, elevated ROS level and MDA content, decreased SOD and GSH-Px activities. The expression of Nrf2 protein in nucleus, HO-1 mRNA and protein were increased (P<0.01). Pretreatment with EGCG promoted the survival of neurons exposed to OGD/R, decreased ROS level and MDA content while increased SOD and GSH-Px activities. The levels of Nrf2 protein in nucleus, HO-1 mRNA and protein were upregulated (P<0.01).
 Conclusion: EGCG can reduce the oxidative stress of neurons subjected to OGD/R, which may be related to activation of Nrf2/HO-1 signal pathway and enhancement of the antioxidant ability of neurons.

Influence of hepatocyte growth factor on iNOS, NO and IL-1β in the cerebrum during cerebral ischemia/reperfusion in rats / 中南大学学报(医学版)

OBJECTIVE@#To explore the effect of hepatocyte growth factor (HGF) on inducible nitric oxide synthase (iNOS), NO and interleukin-1β (IL-1β) in the cerebrum of rats subjected to cerebral ischemia/reperfusion (I/R).@*METHODS@#Sprague-Dawley rats were randomly divided into 5 groups: a sham group, an I/R group,an HGF1 group, an HGF2 group, and an HGF3 group. The latter 3 groups were respectively injected 15, 30 and 60 μg/kg HGF. The focal cerebral I/R model was established by sutureoccluded method. After 1.5 h ischemia followed by 24 h reperfusion, the iNOS activity and NO content in the ischemic cerebral tissue were assessed. The expression of iNOS mRNA and IL-1β mRNA was detected. The level of iNOS protein and IL-1β content were determined. In addition, cultured cerebral cortical neurons in vitro were exposed to I/R. Then the expression of iNOS and IL-1β protein in the neurons was detected, and NO content was assessed.@*RESULTS@#The iNOS activity and NO content in the ischemic cerebral tissue were increased. The expression of iNOS mRNA and IL-1β mRNA was upregulated. The level of iNOS protein and IL- 1β content were increased. Administration of HGF decreased the iNOS activity and NO content, and downregulated the expression of iNOS mRNA, IL-1β mRNA, iNOS protein and IL-1β content in the ischemic cerebral tissue. HGF decreased the expression of IL-1β, iNOS protein and NO content in the cortical neurons exposed to I/R in vitro.@*CONCLUSION@#HGF can inhibit the expression of IL-1β and decrease the expression of iNOS and content of NO, which is probably one of the mechanisms mediating the protection of HGF against cerebral ischemia injury.

Determination of Chlorogenic Acid in Fructus Chaenomelis and Its Wine Processing Products of Different Area by HPLC / 医学研究杂志

Objective To establish a HPLC method to determine the content of chlorogenic acid in Fructus Chaenomelis and its wine processing products.Methods Separation column was Agilent SB-C18(4.6mm?250mm,5?m) with the column temperature of 25℃.The mobile phase composition was methonal-1%HAc (80:20). The mobile speed was 1.0ml/min.The UV detection wavelength was 326 nm. Results A good linearity was obtained in the range of 5.47～71.14?g/ml,with r=0.9999. The average recovery was 101.98%,and RSD was 2.08% (n=6). Conclusion The content of chlorogenic acid was vary with the producing area of Fructus Chaenomelis.After wine processing,the content of chlorogenic acid was raised.The method was good for determining chlorogenic acid in Fructus Chaenomelis.

Study on the Ultrasonic Extraction of Flavonoids from Ramulus Mori / 医学研究杂志

Objective To optimize the ultrasonic extraction technology of flavonoids from Ramulus Mori. Methods Ultrasonic extraction technology was optimized by orthogonal test,and the content of total flavonoids was determined by spectrophotometry. Results The optimal condition was:extracting for 3 times and 20 min for each time,with 8 fold of 80% ethanol. Conclusion The ultrasonic extraction technology was simple,rapid and high efficient.

Study on microwave-assisted extraction technique of flavonoid from Ophiopogon japonicus / 中华中医药杂志

Objective:To study microwave-assisted extraction technique of flavonoids from Ophiopogon japonicus. Methods:The effect of the parameters,i.e.ratio of solid to liquid,microwave treatment time,microwave power and volume ratio of ethanol on extraction amount of flavonoid were analyzed by single factor experiment.Results:Optimum processing data were determined as follows:90.0% ethanol as extracting solvent,stock ratio 1:14(g/ml) ,microwave extracting for 4 minutes at the power of MED. The extraction rate was 39.7% higher than that of non-microwave's.Conclusion:Extraction of flavonoids by microwave from Ophiopogon japonicus is an eficient method.

Study on Quality Standard of Jinwang Capsules / 中成药

Objective: To establish the quality standard of Jinwang Capsules.Methods: The technique of TLC was used to identify 10-Hydroxy-2-decylenic acid (10-HDA). Its content was determined by dual-wavelength UV spectrophotometry.Results: 10-HDA can be detected by TLC. The content of 10-HDA wasn't lower than 3.0mg per granule. Volatile alkalescent substance wasn't more 100mg per 100g.Conclusion: These methods are able to effectively control the quality of Jinwang Capsules.