Paraoxonase-1 (PON1) rs662 Polymorphism and Its Association with Serum Lipid Levels and Longevity in the Bama Zhuang Population

PON1 rs662, rs854560 and TRIB1 rs17321515, rs2954029 Gene Polymorphisms Are Associated with Lipid Parameters in Patients with Unstable Angina

Acute coronary heart disease (CHD) is mainly caused by the rupture of an unstable atherosclerotic plaque. Many different factors can cause stenosis or even occlusion of the coronary artery lumen, such as vasculitis and platelet aggregation. Our study was performed to assess the association between PON1 rs662, rs854560 and TRIB1 rs17321515, rs2954029 polymorphisms and the risk of CHD, as well as the association between studied polymorphisms and selected clinical parameters affecting the risk of developing ischemic heart disease. A total of 232 patients with unstable angina were enrolled in this study. There were no statistically significant differences in the PON1 rs662, rs854560 and TRIB1 rs17321515, rs2954029 polymorphism distributions between the total study and control groups. Total cholesterol plasma levels were significantly higher in patients with the PON1 rs662 TT genotype compared to those with the CC+TC genotypes, as well as in patients with the PON1 rs854560 TT genotype compared to those with the AA+AT genotypes. LDL plasma levels were significantly increased in patients with the PON1 rs854560 TT genotype compared to those with the AA+AT genotypes. Plasma levels of HDL were significantly decreased in patients with the TRIB1 rs17321515 AA+AG genotypes compared to those with the GG genotype, as well as in patients with the TRIB1 rs2954029 AA+AT genotypes compared to those with the TT genotype. Our results suggest that the analysed polymorphisms are not risk factors for unstable angina in the Polish population. However, the results of this study indicate an association between the PON1 rs662, rs854560 and TRIB1 rs17321515, rs2954029 polymorphisms with lipid parameters in patients with coronary artery disease.

Improved diagnostic value by combining plasma PON1 level with tumor biomarkers in Colorectal Cancer patients

The incidence of colorectal cancer (CRC) ranks third among all cancers in China and improvements in screening for CRC have an important impact on prevention and control of the disease. Paraoxonase 1 (PON1) is a calcium ion-dependent hydrolase that is widely distributed in tissue. Its diagnostic value in colorectal cancer has been reported, but the diagnostic value of combining PON1 with carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), carbohydrate antigen 12-5 (CA12-5) in colorectal cancer has not been evaluated. Experiments were carried out in a total of 284 CRC patients and 90 healthy controls. The primary cohort was randomly divided into training and validation sets. The levels of PON1 in plasma of CRC patients were significantly lower than that in the healthy controls (P < 0.001). It showed excellent diagnostic value with the AUC reaching 0.750 for the training set and 0.742 for the validation set. Furthermore, combining PON1 with CEA, CA12-5, CA19-9 could better classify CRC patients (AUC rising from 0.821, 0.716, 0.712 to 0.875, 0.817 and 0.814, respectively, in the training set, from 0.818, 0.581, 0.593 to 0.854, 0.770, and 0.772 in the validation set). In conclusion, PON1 can serve as a diagnostic biomarker for CRC and raise the sensitivity and specificity when incorporated with traditional tumor biomarkers.

Paraoxonases Activities and Polymorphisms in Elderly and Old-Age Diseases: An Overview

Aging is defined as the accumulation of progressive organ dysfunction. There is much evidence linking the involvement of oxidative stress in the pathogenesis of aging. With increasing age, susceptibility to the development of diseases related to lipid peroxidation and tissue injury increases, due to chronic inflammatory processes, and production of reactive oxygen species (ROS) and free radicals. The paraoxonase (PON) gene family is composed of three members (PON1, PON2, PON3) that share considerable structural homology and are located adjacently on chromosome 7 in humans. The most studied member product is PON1, a protein associated with high-density lipoprotein with paraoxonase/esterase activity. Nevertheless, all the three proteins prevent oxidative stress. The major aim of this review is to highlight the importance of the role of PON enzymes in the aging process, and in the development of the main diseases present in the elderly: cardiovascular disease, diabetes mellitus, neurodegenerative diseases, and cancer.

Paraoxonase 1 Activity, Polymorphism and Atherosclerosis Risk Factors in Patients Undergoing Coronary Artery Surgery

Background: Paraoxonase1 (PON1), an enzyme connected to high density lipoproteins (HDL) particles, plays an important role in protecting arteries against atherosclerosis. The serum activity and concentration of PON1 depends on several genetic polymorphisms as well as environmental factors. Materials and methods: Investigated population consisted of 71 patients aged 43–76 years with confirmed coronary heart disease (CHD). Established risk factors of CHD such as hypertension, elevated total cholesterol and LDL cholesterol (LDL-C), low HDL cholesterol (HDL-C), diabetes mellitus, obesity, smoking and premature CHD in family history were assessed. PON1 genotype for −108C/T promotor region was determined by polymerase chain reaction-restriction fragments length polymorphism (PCR–RFLP) method. Paraoxonase activity towards paraoxon and arylesterase activity towards phenyl acetate were measured spectrophotometrically. Results: Significant correlations between diabetes mellitus and paraoxonase activity (R = −0.264, p = 0.026) and between the premature coronary heart disease in family history and PON1 activity (R = −0.293, p = 0.013) were found. In multivariate analysis, PON1 paraoxonase activity was independently of confounding factors associated with diabetes (OR = 0.985; p = 0.024) and premature CHD in family history (OR = 0.983; p = 0.027). PON1 activity towards aryl acetate positively correlated with HDL-C level (R = 0.255, p = 0.032). In patients treated with statins, PON1 paraoxonase activity was significantly (p = 0.033) higher than in patients without treatment. Conclusions: In diabetic patients with CHD, paraoxonase activity is lower than in normoglycemic patients despite similar lipid profiles. Diabetes and positive family history in patients with overt CHD are associated with the serum PON1 activity, which might be an additional factor helpful in evaluating cardiovascular risk in this group of patients.

Decreased serum PON1 arylesterase activity in familial hypercholesterolemia patients with a mutated LDLR gene

Paraoxonase 1 (PON1) is a serum enzyme associated with high density lipoprotein (HDL) regulation through its paraoxonase and arylesterase activity. PON1 inhibits the oxidation of HDL and low density lipoprotein (LDL), and is involved in the pathogenesis of a variety of diseases including atherosclerosis. Conversely, mutations in the low density lipoprotein receptor (LDLR) result in failure of receptor mediated endocytosis of LDL leading to its elevated plasma levels and onset of familial hypercholesterolemia (FH). In the current study we investigated the role of PON1 polymorphisms rs662; c.575A > G (p.Gln192Arg) and rs854560; c.163T > A (p.Leu55Met) in a large family having FH patients harboring a functional mutation in LDLR. Genotypes were revealed by RFLP, followed by confirmation through Sanger sequencing. PON1 activity was measure by spectrophotometry. Our results show significantly reduced serum paraoxonase and arylesterase activities in FH patients compared with the healthy individuals of the family (p < 0.05). PON1 QQ192 genotype showed a significantly higher association with FH (p=0.0002). PON1 Q192 isoform was associated with reduced serum paraoxonase activity by in silico analysis and PON1 R192 exhibited higher serum paraoxonase and arylesterase activity than the other polymorphs. Our results highlight that the combination of LDLR mutations and PON1 MMQQ genotypes may lead to severe cardiac events.

Spatio-Temporal Variation of Longevity Clusters and the Influence of Social Development Level on Lifespan in a Chinese Longevous Area (1982-2010)

The study aims to determine the spatial and temporal variation of a longevous region and explore the correlation between longevity and socioeconomic development. Population data at the township level were obtained from the last four population censuses (1982-2010). Five main lifespan indicators and the Human Development Index (HDI) were calculated. Getis-Ord G*, Gravity modeling, and Pearson's r between lifespan indicators and HDI were applied. In this study, a stable longevous gathering area was discovered in Hechi during different periods. Under the influence of social and economic development, more longevous areas appeared. However, the effects of genetic and natural environmental factors on longevity were always dominant in this remote and mountainous city. Furthermore, longevity indicators lacked any significant correlation with life expectancy. No significant positive correlation was detected between lifespan indicators and HDI. Thus, we conclude that lifespan indicators can determine the spatial distribution and variation pattern of longevity from multiple dimensions. The geographical scope of longevity in Hechi City is gradually expanding, and significant spatial clustering was detected in southwestern, southern, and eastern parts of Hechi. This study also found that social economic development is likely to have a certain impact on new longevous areas, but their role on extreme longevity is not significant.

Apolipoprotein C-I Polymorphism and Its Association with Serum Lipid Levels and Longevity in the Bama Population

This study aims to determine the association between the apolipoprotein C-I polymorphism and the longevity and genetic variants in ApoC-I that can influence the serum lipid levels in Bama. ApoC-I genotypes were determined by Taqman single nucleotide polymorphism (SNP) genotyping assays in 178 long-lived inhabitants (longevity group aged from 90 to 110 years), 147 healthy controls (Control 1 group aged from 40 to 79 years old) from Bama County, and 190 healthy controls (Control 2 group aged from 40 to 79 years old) from Nandan County without a family history of longevity. Statistical analysis was conducted using SPSS 16.0. All genotype distributions of rs584007 and rs4420638 were consistent with the Hardy-Weinberg equilibrium (p > 0.05). Significant differences were observed in the frequencies of the three genotypes (GG, AG, and AA) among the longevity and the two control groups (χ² = 11.238, p = 0.024) for rs584007. No significant differences were observed in the frequencies of the three genotypes (GG, AG, and AA) among the longevity and the two control groups (χ² = 4.587, p = 0.318) for rs4420638. The levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-c), and low-density lipoprotein-cholesterol (LDL-c) were not different among the three genotypes of rs584007 in the three groups. The levels of HDL-c for GG, AG, and AA were significantly different (the highest being in the longevity group), while the levels of TG for AA and AG genotypes (the lowest being in the longevity group) and the levels of LDL-c for AG were significantly different (p < 0.05) among the three groups for rs584007. The levels of TG and HDL-c were significantly different among the three rs4420638 genotypes in the longevity group. The levels of TC for GG, AG, and AA were significantly different in the Control 2 group, while the levels of TG and HDL-c for AA and AG genotypes were significantly different (p < 0.05) among the three groups for rs4420638. The level of HDL-c was highest in the longevity group for AA and AG genotypes, and the level of TG was highest in the Control 2 group for rs4420638. Serum lipid parameters were related to environmental factors, including age, gender, BMI, DBP, SBP, rs4420638, and rs584007. The ApoC-I polymorphism might be one of the genetic factors of longevity in Bama. The ApoC-I rs4420638 and rs584007 SNPs are associated with serum TG and HDL-c levels in the longevous population.