Preparation Of Gypenoside Nanoemulsion And Research On Its Antioxidant Effect

Gypenosides?Gyp?is the main medicinal component of Gynostemma pentaphyllum?Thunb.Makino?.Previous studies have found that Gypenosides?Gyp?have hypoglycemic,hypolipidemic,anti-tumor,anti-tumor Aging,protecting the liver and enhancing the body's immune function.Studies have shown that Gyp has good antioxidant effects in vitro and in vivo.When the body is subjected to various harmful stimuli or changes with time,the balance between the antioxidant system and the oxidative system in the body changes,and the rate of generation of free radicals generated in the body greatly exceeds the clearance rate,resulting in various types of free radicals in the body.Accumulation occurs.The introduction of antioxidants stabilizes the balance between the antioxidant system and the oxidation system in the body.In this paper,Gyp-NE nano drug delivery system was constructed by nano-encapsulation of Gyp,and the anti-oxidation effects of Gyp-NE and Gyp in vitro and in vivo were explored.The NIH-3T3 cell oxidative damage model was established and further explored.The specific antioxidant mechanism of Gyp-NE provides basic theoretical data for Gyp's antioxidant research.The main experimental results are as follows:1.Construction and characterization of Gyp-NE nano drug delivery systemIsopropyl myristate?IPM?was used as the oil phase,polyoxyethylene hydrogenated castor oil?RH40?was used as the surfactant,and 1,2-propanediol was used as the co-surfactant to prepare Gyp-NE by low-energy emulsification.The ratio between the surfactant and the co-surfactant of the surfactant was screened,and it was found that the ratio of the oil phase to the mixed surface agent was 1:10,and the ratio of the surfactant to the co-surfactant was 3:1.The appearance of Gyp-NE is light yellow,clear and transparent liquid,the particle size distribution is 14.95±0.81 nm,the polydispersity coefficient is 0.235,and the particle size will remain stable within 30 days,and it is spherical granules of uniform size under transmission electron microscope.Nanocrystallization of the package can significantly improve the hemolytic properties of Gyp,and in vitro release shows that Gyp-NE has a faster release rate than Gyp.2.Evaluation of in vitro antioxidant activity of Gyp-NEThrough the evaluation of Gyp-NE in vitro antioxidant activity,it was found that nano-sized Gyp can significantly improve the DPPH free radical scavenging ability,hydroxyl radical scavenging ability and ferrous reduction ability of Gyp.When the drug concentration is 1.0 mg/mL,The clearance ability of Gyp-NE to DPPH free radicals reached 90.03%;in the concentration range of 2 mg/mL?5 mg/mL,Gyp-NE had stronger hydroxyl radical scavenging ability than Gyp,accompanied by dose-dependent effect;In the concentration range of 1 mg/mL-5 mg/mL,the ferrous reduction ability of Gyp-NE and Gyp increased with the increase of concentration,and the ferrous reduction ability of Gyp-NE increased with concentration compared with Gyp obviously.3.Evaluation of in vivo antioxidant activity of Gyp-NETo establish a D-galactose subacute aging mouse model,Gyp-NE has a stronger anti-oxidase level than Gyp,which can reduce the levels of TG and LDL in serum,HDL,CAT,GSH-Px,The content of SOD tends to be normal or higher than normal.The contents of CAT,GSH-Px,SOD,NO,T-AOC and MDA in liver tissue tend to be normal to some extent,and it is observed from histopathological pictures that nanoemulsion The dosage form has no significant effect on kidney tissue,indicating that Gyp-NE has no obvious toxic effect,and Gyp-NE can significantly increase the mRNA expression of CAT and GSH-Px in liver tissue.4.Gyp-NE pretreatment against oxidative damage in NIH-3T3 cellsIn this chapter,by screening the conditions of NIH-3T3 cell oxidative damage model,1 mM H₂O₂ treatment of cells can cause damage to cells,and the amount of ROS production is also significantly increased,accompanied by an increase in LDH content.To investigate the effect of Gyp-NE on cell viability,Gyp-NE had no significant effect on cell viability in the range of 0.5?2 ?g/mL,and did not decrease with increasing dose.Pretreatment of Gyp-NE It can significantly reduce the amount of ROS produced by H₂O₂,and at the same time,the G1 phase arrest caused by H₂O₂ can be restored to near normal level.The CAA results show that H₂O₂ severely destroys the antioxidant properties of cells,while the pretreatment of Gyp-NE makes cells the ability to fight oxidative damage has increased.