Serum level of MMP-2, MMP-9 and Ox-LDL in Alzheimer's disease with hyperlipoidemia*

ObjectiveTo investigate serum levels of MMP-2, MMP-9, oxidized low-density lipoprotein (ox-LDL) in Alzheimer's disease (AD) patients and study the possible pathway and mechanism of AD with abnormal lipid metabolism.MethodsSubjects in this study were divided into 4 groups; normal lipid group without AD (N), hyperlipoidemia group without AD (H), normal group with AD (A), hyperlipoidemia group with AD (AH). There were 15 individuals in each group. MMP-2, MMP-9, ox-LDL was measured by enzyme linked immunosorbent assay (ELISA). Serum lipids levels were measured by biochemical methods.ResultsThe serum levels of MMP-2, MMP-9, ox-LDL were significantly higher in H. A and AH groups than those in N group. Those of ox-LDL in H, AH groups was higher than that of in A group. The serum level of MMP-2, MMP-9 in AH groups were higher than that of in H group. The score of mini-mental state examination (MMSE) in A and AD groups was negatively correlated with the serum level of ox-LDL. Relationship between the score of MMSE and the serum level of ox-LDL in AD groups and non-AD groups had statistical significance.ConclusionMMP-2, MMP-9, ox-LDL and abnormal lipid metabolism may participate in pathogenesis of AD, in which abnormal lipid metabolism induces expressions of MMP-2, MMP-9 and ox-LDL. Oxidative stress and blood-brain barrier disruption might accelerate the process of AD.