| Objective Currently metabolic diseases and infectious diseases,as well as primary and secondary tumors, are easily found in liver. China is hepatopathy high risk area and more than one-tenth of the population has HBV infection, with a significantly higher occurrence of positive hepatitis B than negative HBsAg. Primary liver cancer ranking the second leading cause among all tumor deaths in China, it is of great significance to study therapeutic drug of hepatic targeting property.The major mechanism of achieving its drug delivery is to use special carriers, of which nano-carrier is able to change the distribution of drugs inside,thus showing the targeting property of drug distribution.Drug-carried nano-particles will be instantly absorbed by RES. With RES mainly spreading in liver, it is possible to achieve hepatic targeted drug delivery based on the effect of passive targeting. Liposome, with multilamellar vesicle, every layer being membrane, interlayer&liposome kernel in water phase, double molecule membrane being oil phase, is a kind of molecular organized assembly formed spontaneously in water,depending on the hydrophobic association of phospholipid.Drug-carried nano-particles, which can be degraded with low immunogenicity and low toxicity when taken in, are of the qualities and functions of biofilm structure like cell structure,. Therefore, they have been extensively applied in water-soluble and lipophilic drugs.Quercetin and its derivatives are the most diverse and widespread flavonoids in nature, with the pharmacological activity of anti cancer, anti inflammation, free radical scavenging, antivirus, drug resistance against some tumors, vessels dilation, decreasing blood pressure, and intensifying immunity. Quercetin shows significant cytotoxicity on hepatoma cells, being able to inhibit effectively the growth of hepatoma cells, with good protective effect of liver injury and certain anti-hepatic fibrosis effects.Since its common preparation with poor quality of targeting is undissolved, the direct application of it has an effect on blood coagulative system,which limits the application of liver disease therapy. On the above basis, nano-granulated quercetin liposome made of Quercetin encapsulated in nano-Liposome as Carrier is able to improve the water solubility of drug delivery system,achieving hepatic targeted drug delivery and aggregating nano-drug in liver.This paper is first to prepare nano-granulated quercetin liposome, to verify its targeting property and its efficiency in vivo metabolism,and then to apply it to the evaluation of model animal with liver injuries and the protective effect.Methods High pressure homogeneous and pressure evaporation technology was adopted in preparing nano-granulated quercetin liposome; transmission electron microscope and particle size analyzer were used to observe its morphological feature and measure its particle size; the drug content and entrapment efficiency were measured by HPLC. The hepatectomined mouse modal was made by CCL4plus swain serum and alcoholic diet; HPLC method was established to measure plasma of the modal mouse and quercetin in various tissues. Given quercetin and quercetin nanoliposomes, the grouped hepatectomined mice were observed to detect the time and space distribution of quercetin in their bodies and to testify its targeting index. In order to provide evidence to pharmacodynamics, some normal rats were given nano-granulated quercetin liposome and their metabolites in serum were analyzed to see if there were pharmaceutical components by liquid chromatography masss pectrometry (LCMS). The hepatectomined rats were grouped by weight as normal group, hepatectomined modal group, nano-granulated quercetin liposome group, quercetin group and empty nanoliposomes group, and given different doses of drug. After that, ALT, AST, TBiLi, TBA, TP in the serum, liver coefficient, pathological change in liver and MDA, GSAH-px, SOD, LN, HA, PCⅢ, IV-C of the five groups were compared. At the same time, by comparing Bcl-2of liver and Bax protein expression of the five groups, the liver-protecting mechanism of quercetin nanoliposomes was explored.Results The size of nano-granulated quercetin liposome obtained from the experiment is123±31nm, the Nanoparticles are kind of circular which covered by coating of uniform thickness and with a uniform size distribution. The HPLC system built for testing nano-granulated quercetin liposome separated well, has a good precision, reproducibility and method recovery as well.The entrapment rate was91.18±0.78%drugloading was0.61±0.08mg/mg.The hepatectomined rats in this experiment can meet the requirement of test. The HPLC system built for testing quercetin in plasma and organs separated well, has a good precision, reproducibility and method recovery as well.The drug half-life of Quercetin within the body of the liver injury model rat is10min, but the drug half-life of the nano-granulated quercetin liposome drug within the body of the model rats reaches to2h. This is because the Liposome prolongs the circulation time of Quercetin in the body of the model rat and the nano-granulated quercetin liposome drug has some slow release effects. The Quercetin within the body of the model rats can accumulate in the liver after being injected nano drug for5minutes, and it will become more apparent if exceeding10minutes, which is also obviously high than the control group(p<0.05). The nano drug made of Quercetin improved its topotaxis towards liver and spleen as well as decreases the topotaxis towards heart and lung; meanwhile, the nano granulated quercetin liposome has very good hepatic targeting, when the doses of the nano-granulated quercetin liposome increases to100mg/kg, the model rat dies. The chromatography and mass spectrometry conditions measured in the Quercetin metabolites within the plasma of the model rat can meet the experiment requirements, and using liquid chromatography-mass spectrometry can confirm that the plasma metabolites of the model rat contains Quercetin, Tamarixetin, Isorhamnetin and some other medical components. The normal situation of rats in the nano-granulated quercetin liposome group and quercetin group are significantly better than the hepatectomined model control group and blank nano-liposomes group but is a bit worse than the normal control group. Compared with the injury control group, the Quercetin group and blank nano-liposome group, the nano granulated quercetin liposome in serum such as AST,ALT, TBiLi, TBA, TP, ALB and liver indexes such as MDA, GSH-Px, SOD, LN, HA, PCⅢ, Ⅳ-C increases to some extent.The protection of liver function for liver injury model rats from nano-granulated quercetin liposome, Quercetin and blank liposome nano drug in the field of AST, ALT, TBiLi and TBA presents a high to low dose-effect dependable relationship. According to the light microscopic observation of livers from each model rat, it can be recognized that if it using the same dose, the liver lesion situation of the nano granulated quercetin liposome group is much better than the Quercetin group and blank nano-liposomes group. Namely, the liver lesion situation of high dose of the nano-granulated quercetin liposome group is much close to the normal control group. At the same time, the blank nano-liposomes also improves the liver lesion situation for the hepatectomined rats. The expression of protein Bcl-2of the liver within the model rat in the injury model control group, the high dose of nano-granulated quercetin liposome group, the high dose of Quercetin drug group, the high dose of the blank nano-liposomes and the normal control group increases successively, while the expression of protein Bax decreases in turn.Conclusions The granularity of the prepared nano-granulated quercetin liposome is distributed evenly with high drug load and encapsulated efficiency. The Nanometer-Granulated Quercetin Liposome prepared in this experiment has very strong affinity with the experimented rat of liver injury model and very good hepatic targeting, so it is a very ideal targeting administration system. The nano-granulated quercetin liposome prepared in this experiment also has very good spleen targeting with a certain slow release effects, which can maintain a long period of plasma concentration. The nano-granulated quercetin liposome exists some medical ingredients including Quercetin, Tamarixetin and Lsorhamnetin in the plasma metabolites within the body of normal rats. The protection of the nano-granulated quercetin liposome towards the model rat is superior to the Quercetin and blank liposome. What's more, it represents a positive phasor effect relationship. At and over100mg/kg of the nano-granulated quercetin liposome may produce lethal toxicity. The mechanism of the protection towards liver by the nano-granulated quercetin liposome aims to decrease the MDA level of the liver, strengthen the activity of SOD and GSH-px towards the liver, increase the expression of protein Bcl-2and lessen the expression of protein Bax. The blank liposome drug also has efficacy of protecting liver and represents a positive phasor effect relationship as well.
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