The Effect Of Liposomes Loaded With Crosslinked Hualuronic Acid On The Metabolism Time Of Hyaluronic Acid Was Preliminarily Studied

Objective:1)To investigate the influence of the presence of liposomes on the metabolism time of hyaluronic acid.2)To verify the degree of inflammatory response of liposomes loaded with hyaluronic acid to local tissues.3)To compare the difference of HA-liposome and HA in hyaluronidase dissolution.Methods:34 SD rats were randomly divided into experimental observation group(n = 20)and pathological observation group(n = 14).Using the same injection method,filling site and dose,HA and HA-liposome were injected into the left and right symmetrical parts of the back of 34 rats.Immediately after injection,the subcutaneous thickness,transverse diameter and longitudinal diameter(unit: mm)of the filling material were detected by B-ultrasound at 2W,4W,8W,12 W,16W,20 W and 24 W.Two rats were sacrificed each time at 2W,4W,8W,12 W,16W,20 W and 24 W,and local skin specimens were taken for pathological observation.In vitro enzymatic hydrolysis experiment was conducted to observe the effect of liposomes modified with hyaluronic acid on enzymatic hydrolysis time.Results:1)The data of the control group and the experimental group at 2W were compared with the data of the two groups immediately after injection,indicating that the data of the control group and the experimental group at 2W were slightly increased compared with the data immediately after injection.It was observed that the mean thickness and transverse diameter of 0W-8W were basically the same between the control group and the experimental group,while the mean longitudinal diameter of the control group was greater than that of the experimental group,with no statistically significant difference(P >0.05).From 12 W to 24 W,the mean thickness,transverse diameter and longitudinal diameter of the experimental group were higher than those of the control group,with statistical significance(P < 0.05).2)The staining results showed that pathological sections of the two groups were made at2 W,4W,8W,12 W,16W,20 W and 24 W.At 2W,macrophage infiltration could be seen under the microscope in the control group,which was significantly more in the experimental group than the control group.The pathological sections of 4W-12 W control group and experimental group showed that the inflammatory response was gradually reduced and the inflammatory cells were gradually reduced.The local hyperplasia and hypertrophy of 16W-24 W experimental group was more obvious than that of the control group,but the inflammatory response of the two groups had basically disappeared.3)In vitro enzymatic hydrolysis experiment showed that,after controlling the temperature,volume and dissolution time,hyaluronidase was added to HA-liposome and HA,and the enzymatic hydrolysis of HA-liposome group was significantly larger than that of HA group,and the time of complete enzymatic hydrolysis of HA-liposome was longer than that of HA group.Conclusion:After 6 months of experimental data analysis,it was found that the liposom-modified hyaluronic acid could delay the metabolic time in rats to some extent.At the same time,it was found in the study that the presence of liposomes may lead to the enlargement of HA-liposome granules,and the extrusion of local tissues after filling is obvious,causing more obvious inflammatory reactions at the filling site than that of HA,but the inflammatory reactions caused are reversible.