The Association of Paraoxonase-1 Polymorphism with Carotid Artery Stenosis among Elderly Chinese Population.

Elderly population is in high risk of carotid atherosclerosis and artery stenosis (CAS). It has been proved that PON1 polymorphism is associated with low-density lipoprotein (LDL) oxidation, which plays an important role in artery atherosclerosis. CAS is an important cause of ischemic stroke. This study is aimed at investigating the association of PON1 (rs662) polymorphism with the risk of CAS among elderly Chinese population. Consecutive elderly patients with CAS were enrolled into the study. Genotyping for PON1 (rs662) polymorphism was performed on all participants. There were 310 CAS patients in this study, with 88 symptomatic CAS and 222 asymptomatic CAS. G allele had a frequency of 59.66% in symptomatic CAS (sCAS); and A allele had an incidence of 36.93% in asymptomatic CAS (aCAS) (P < 0.05). In all CAS patients with and without symptom, no associations were found in any genotype comparison. However, among aCAS subjects, based on GA phenotype, the odds ratio (OR) of the mutant GG with stenosis severity was 0.20 (P = 0.01). The OR of GG+GA mutation was 0.28 for moderate/severe severity, compared with GA type (P = 0.03). This study indicates that PON1 (rs662) polymorphism is not associated with the presence of symptom among CAS patients. Moreover, PON1 (rs662) polymorphism correlates with stenosis severity among aCAS.

High C-reactive protein and low paraoxonase1 in diabetes as risk factors for coronary heart disease.

BACKGROUND: Paraoxonase1 (PON1) is an anti-inflammatory enzyme located on HDL, which protects against the development of atherosclerosis. C-reactive protein (CRP) is a marker of the inflammatory response in CHD. We hypothesised that low PON1 and high CRP found in CHD may be important markers of CHD and the CRP:PON1 ratio may be an index of the risk of developing atherosclerosis. We have, therefore, compared the levels of PON1 and CRP between control subjects, those with no diabetes and CHD, type 1 diabetes and type 2 diabetes. METHODS AND RESULTS: PON1 activity was different between the populations in the order: controls > type 1 diabetes > type 2 diabetes > CHD with no diabetes (P<0.001). CRP concentration also differed between the populations in the order: controls < type 1 diabetes < type 2 diabetes < CHD with no diabetes (P<0.001). The CRP:PON1 ratio followed the same trend as the CRP concentration (P<0.001). Both CRP and the CRP:PON1 ratio were associated with the presence of CHD. In the control population only, PON1 was a determinant of CRP concentration. Amongst the diabetics, people with CHD had higher levels of CRP (P<0.001) and in comparing the control group with the CHD group, the CHD group had a higher level of CRP (P<0.001). CONCLUSIONS: Higher levels of CRP seem to be generally associated with low levels of PON1 activity, providing a mechanistic link between inflammation and the development of atherosclerosis. However, the relationship between PON1, CRP and atherosclerosis, and the usefulness of the PON1:CRP ratio as a risk factor for CHD requires further evaluation.