Meta-analysis Of Tea Consumption And Osteoporosis And The Exploration Of The Optimized Of The Preparation Of EGCG-dispersed Selenium Nanoparticles

Tea(Camellia sinensis(L.)O.Kuntze),from the tea shrubs,has been seen as a kind of health promotion drink,which can fight against many kinds of disease long before.As an important component of tea,(-)-epigallocatechin-3-gallate(EGCG)has a strong biological effect.Selenium,widely presented in the tea,acts as an indispensable trace element and is able to resist a variety of cancers.Osteoporosis(OP)is a metabolic bone disease characterized by an increase in bone resorption associated with a reduction in bone formation and it can lead to a reduction in bone density and a deterioration in bone mass resulting in a risk of fracture.There have been many human studies on the relationship between tea consumption and OP,but the arguments were different.This study tried to explore the relationship between tea consumption and osteoporosis,using a meta-analysis method to find the relationship between them.Then considering the composition of tea,EGCG and selenium elements were regarded as basis while nanoparticle was carrier to prepare Selenium nanoparticles(SeNPs)by optimizing the preparation condition.Exploring its property in extrem acid or high temperature environment and analyzing the oral bioavailability to increase the attainablility and utilization of this kind of EGCG-SeNPs.The main methods used and the main results obtained in this study are as following:1.Tea consumption can reduce the risk of OP.We systematically searched the databases of PubMed,EMBASE and Wanfang by the end of March 30th in 2016,without any language restriction.Odds Ratios(OR)with 95%Confidence Intervals(CI)were derived by using random-effects models throughout all analyses.We conducted the analysis of the statistical heterogeneity using Cochrane I2.By using subgroup analysis and multi-round elimination method that we found the main source of the heterogeneity.Funnel plot was used to infer the publication bias.Our meta-analysis was based on 17 studies,including two prospective cohort studies,four case-control studies and 11 cross-sectional studies.We figured that the total OR of OP for the tea consumption was 0.62(95%CI,0.46-0.83),with its significant heterogeneity among studies(I2 = 94%,p<0.01).Funnel plot showed that there was no publication bias of the meta-analysis about tea consumption and OP.Subgroup analyses showed that tea consumption could reduce the risk of OP in all subgroups examined.2.EGCG-Selenium nanoparticles(EGCG-SeNPs)can be successfully prepared under the condition of acid before and alkaline later when EGCG was used as the dispersant and vitamin C as the.redox agent,with good stability and oxidative resistance.At room temperature,the appropriate amount of EGCG and a certain concentration of sodium selenite solution were mixed,then a certain amount of vitamin C was add for mixing,the solution was adjusted to pH 2.5 at first and stired for 5 minutes and finally turned to pH 8.5.It was confirmed as nano collid by using Tindal effect.The nanoparticles were characterized by transmission electron microscopy(TEIM)and Zetasizer.The results showed that the particle size was 35 ± 0.12 nm and the Zeta potential was-0.05 mV.And the pH and temperature characteristics of EGCG-SeNPs were investigated.The content of EGCG in EGCG-SeNPs was determined by ultra-high performance liquid(UPLC).It was found that EGCG content did not change significantly before and after one month.And the antioxidant resistance of EGCG-SeNPs was detected by 1,1-diphenyl-2-bitteryl hydrazine(DPPH)and reactive oxygen species(ROS)methods.3.EGCG-SeNPs synthesized by Vc as a redox agent aggregated so slightly when passing through the gastric acid environment that the bioavailability was well conserved.The contents of selenium and the activity of glutathione peroxidase(GPx)were measured by intragastric administration of EGCG-SeNPs and Sodium selenite at the same concentration(25,50,100 ?g Se/kg)to the selenium deficient ICR male mice.The results showed that the selenium content and GPx activity of Sodium selenite and EGCG-SeNPs were significantly increased in a dose-dependent manner.However,there was no significant difference in selenium content and GPx activity between Sodium selenite and EGCG-SeNPs at the same dose.