Paraoxonase-1 and serum concentrations of HDL-cholesterol and apoA-I

Effects of Metabolic Disruption on Lipid Metabolism and Yolk Retention in Zebrafish Embryos

A subgroup of endocrine-disrupting chemicals have the ability to disrupt metabolism. These metabolism-disrupting chemicals (MDCs) can end up in aquatic environments and lead to adverse outcomes in fish. Although molecular and physiological effects of MDCs have been studied in adult fish, few studies have investigated the consequences of metabolic disruption in fish during the earliest life stages. To investigate the processes affected by metabolic disruption, zebrafish embryos were exposed to peroxisome proliferator-activated receptor gamma (PPARγ) agonist rosiglitazone, the PPARγ antagonist T0070907, and the well-known environmentally relevant MDC bisphenol A. Decreased apolipoprotein Ea transcript levels indicated disrupted lipid transport, which was likely related to the observed dose-dependent increases in yolk size across all compounds. Increased yolk size and decreased swimming activity indicate decreased energy usage, which could lead to adverse outcomes because the availability of energy reserves is essential for embryo survival and growth. Exposure to T0070907 resulted in a darkened yolk. This was likely related to reduced transcript levels of genes involved in lipid transport and fatty acid oxidation, a combination of responses that was specific to exposure to this compound, possibly leading to lipid accumulation and cell death in the yolk. Paraoxonase 1 (Pon1) transcript levels were increased by rosiglitazone and T0070907, but this was not reflected in PON1 enzyme activities. The present study shows how exposure to MDCs can influence biochemical and molecular processes involved in early lipid metabolism and may lead to adverse outcomes in the earliest life stages of fish. Environ Toxicol Chem 2024;43:1880-1893. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Relationship between pattern reversal visual evoked potential P100 wave latency and dysfunctional HDL in patients with multiple sclerosis subjected to an optic neuritis attack: A case-control study

Optic neuritis frequently occurs during the clinical course of multiple sclerosis (MS). In this condition, demyelination of the optic nerve occurs, which electrophysiologically causes a delay in P100 wave latency. Sensitive cholesterol homeostasis is critical for the formation of the myelin sheath and for myelin to become functionally mature. High-density lipoprotein (HDL) becomes dysfunctional under oxidative stress and plays an important role in the pathogenesis of MS. In this study, HDL levels of MS patients suffering from optic neuritis were compared with those of healthy individuals, and the relationship between pattern reversal visual evoked potential (PRVEP) P100 wave latency and HDL levels in patients with optic neuritis attacks was analyzed. PRVEP studies were performed in patients with MS who had an episode of optic neuritis, and P100 wave latencies were measured. Peripheral blood samples were collected from healthy participants and patients. Lipid levels and myeloperoxidase (MPO) and paraoxonase (PON) activities were measured, and the MPO/PON ratio was then calculated. The lipid profiles and dysfunctional HDL levels in the healthy and patient groups were compared. Finally, the relationship between these parameters and the PRVEP-P100 wave latency was examined. Total cholesterol and low-density lipoprotein (LDL) levels were significantly higher in the patient group (P = .044; P = .038, respectively). There was no statistically significant difference in HDL levels between groups (P = .659). The distribution of MPO values was similar between groups (P = .452). PON values were significantly lower, whereas the MPO/PON ratios were significantly higher in the patient group than in the control group (P = .025; P = .028, respectively). A statistically significant positive correlation was found between the elevated MPO/PON ratio, representing dysfunctional HDL, and both the mean and maximum PRVEP-P100 wave latencies (P < .001, R = 0.690; P < .001, R = 0.815, respectively). A dysfunctional form of HDL may lead to poor deactivation of remyelination-limiting factors and may ultimately be associated with poor outcomes in optic neuritis.

Beeswax Alcohol Prevents Low-Density Lipoprotein Oxidation and Demonstrates Antioxidant Activities in Zebrafish Embryos and Human Subjects: A Clinical Study

Oxidative stress is one of the primary instigators of the onset of various human ailments, including cancers, cardiovascular diseases, and dementia. Particularly, oxidative stress severely affects low-density lipid & protein (LDL) oxidation, leading to several detrimental health effects. Therefore, in this study, the effect of beeswax alcohol (BWA) was evaluated in the prevention of LDL oxidation, enhancement of paraoxonase 1 (PON-1) activity of high-density lipid & protein (HDL), and zebrafish embryo survivability. Furthermore, the implication of BWA consumption on the oxidative plasma variables was assessed by a preliminary clinical study on middle-aged and older human subjects (n = 50). Results support BWA augmentation of PON-1 activity in a dose-dependent manner (10-30 μM), which was significantly better than the effect exerted by coenzyme Q10 (CoQ10). Moreover, BWA significantly curtails LDL/apo-B oxidation evoked by CuSO4 (final 0.5 μM) and a causes a marked reduction in lipid peroxidation in LDL. The transmission electron microscopy (TEM) analysis revealed a healing effect of BWA towards the restoration of LDL morphology and size impaired by the exposure of Cu2+ ions (final 0.5 μM). Additionally, BWA counters the toxicity induced by carboxymethyllysine (CML, 500 ng) and rescues zebrafish embryos from development deformities and apoptotic cell death. A completely randomized, double-blinded, placebo-controlled preliminary clinical study on middle- and older-aged human subjects (n = 50) showed that 12 weeks of BWA (100 mg/day) supplementation efficiently diminished serum malondialdehyde (MDA) and total hydroperoxides and enhanced total antioxidant status by 25%, 27%, and 22%, respectively, compared to the placebo-control and baseline values. Furthermore, the consumption of BWA did not exhibit any noteworthy changes in physical variables, lipid profile, glucose levels, and biomarkers pertinent to kidney and liver function, thus confirming the safety of BWA for consumption. Conclusively, in vitro, BWA prevents LDL oxidation, enhances PON-1 activity in HDL, and positively influences oxidative variables in human subjects.

Enhancement of Antioxidant and Anti-Glycation Properties of Beeswax Alcohol in Reconstituted High-Density Lipoprotein: Safeguarding against Carboxymethyllysine Toxicity in Zebrafish

The antioxidant and anti-inflammatory abilities of beeswax alcohol (BWA) are well reported in animal and human clinical studies, with a significant decrease in malondialdehyde (MDA) in the blood, reduced liver steatosis, and decreased insulin. However, there has been insufficient information to explain BWAs in vitro antioxidant and anti-inflammatory activity owing to its limited solubility in an aqueous buffer system. Herein, three distinct reconstituted high-density lipoproteins (rHDL) were prepared with palmitoyloleoyl phosphatidylcholine (POPC), cholesterol, apolipoprotein A-I (apoA-I), and BWA at molar ratios of 95:5:1:0 (rHDL-0), 95:5:1:0.5 (rHDL-0.5), and 95:5:1:1 (rHDL-1) and examined for antioxidant and anti-glycation effects. A rHDL containing BWA, precisely rHDL-1, displayed a remarkable anti-glycation effect against fructose (final 250 mM), induced glycation of HDL, and prevented proteolytic degradation of apoA-I. Also, BWA incorporated rHDL-0.5, and rHDL-1 displayed substantial antioxidant activity by inhibiting cupric ion-mediated low-density lipoprotein (LDL) oxidation. In contrast to rHDL-0, a 20 and 22% enhancement in ferric ion reduction ability (FRA) and paraoxonase (PON) activity was observed in HDL treated with rHDL-1, signifying the effect of BWA on the antioxidant activity enhancement of HDL. rHDL-1 efficiently inhibits Nε-carboxylmethyllysine (CML)-induced reactive oxygen species (ROS) generation and apoptosis in zebrafish embryos, consequently improving embryo survivability and developmental deformities impaired by the CML. The dermal application of rHDL-1 to the CML-impaired cutaneous wound of the adult zebrafish inhibited ROS production and displayed potent wound-healing activity. Conclusively, incorporating BWA in rHDL significantly enhanced the anti-glycation and antioxidant activities in rHDL via more stabilization of apoA-I with a larger particle size. The rHDL containing BWA facilitated the inherent antioxidant ability of HDL to suppress the CML-induced toxicities in zebrafish embryos and ameliorate CML-aggravated chronic wounds in adult zebrafish.

Combined western diet and bisphenol A exposure induces an oxidative stress-based paraoxonase 1 response in larval zebrafish

Paraoxonase 1 (PON1) is an antioxidant enzyme linked to metabolic disorders by genome-wide association studies in humans. Exposure to metabolic disrupting chemicals (MDCs) such as bisphenol A (BPA), together with genetic and dietary factors, can increase the risk of metabolic disorders. The objective of this study was to investigate how PON1 responds to the metabolic changes and oxidative stress caused by a western diet, and whether exposure to BPA alters the metabolic and PON1 responses. Zebrafish larvae at 14 days post fertilization were fed a custom-made western diet with and without aquatic exposure to two concentrations of BPA for 5 days. A combination of western diet and 150 μg/L BPA exposure resulted in a stepwise increase in weight, length and oxidative stress, suggesting that BPA amplifies the western diet-induced metabolic shift. PON1 arylesterase activity was increased in all western diet and BPA exposure groups and PON1 lactonase activity was increased when western diet was combined with exposure to 1800 μg/L BPA. Both PON1 activities were positively correlated to oxidative stress. Based on our observations we hypothesize that a western diet caused a shift towards fatty acid-based metabolism, which was increased by BPA exposure. This shift resulted in increased oxidative stress, which in turn was associated with a PON1 activity increase as an antioxidant response. This is the first exploration of PON1 responses to metabolic challenges in zebrafish, and the first study of PON1 in the context of MDC exposure in vertebrates.

Statin Use in Relation to COVID-19 and Other Respiratory Infections: Muscle and Other Considerations

Statins have been widely advocated for use in COVID-19 based on large favorable observational associations buttressed by theoretical expected benefits. However, past favorable associations of statins to pre-COVID-19 infection outcomes (also buttressed by theoretical benefits) were unsupported in meta-analysis of RCTs, RR = 1.00. Initial RCTs in COVID-19 appear to follow this trajectory. Healthy-user/tolerator effects and indication bias may explain these disparities. Moreover, cholesterol drops in proportion to infection severity, so less severely affected individuals may be selected for statin use, contributing to apparent favorable statin associations to outcomes. Cholesterol transports fat-soluble antioxidants and immune-protective vitamins. Statins impair mitochondrial function in those most reliant on coenzyme Q10 (a mevalonate pathway product also transported on cholesterol)-i.e., those with existing mitochondrial compromise, whom data suggest bear increased risks from both COVID-19 and from statins. Thus, statin risks of adverse outcomes are amplified in those patients at risk of poor COVID-19 outcomes-i.e., those in whom adjunctive statin therapy may most likely be given. High reported rates of rhabdomyolysis in hospitalized COVID-19 patients underscore the notion that statin-related risks as well as benefits must be considered. Advocacy for statins in COVID-19 should be suspended pending clear evidence of RCT benefits, with careful attention to risk modifiers.

Protection of Liver Functions and Improvement of Kidney Functions by Twelve Weeks Consumption of Cuban Policosanol (Raydel®) with a Decrease of Glycated Hemoglobin and Blood Pressure from a Randomized, Placebo-Controlled, and Double-Blinded Study with Healthy and Middle-Aged Japanese Participants

Policosanol consumption has been associated with treating blood pressure and dyslipidemia by increasing the level of high-density lipoproteins-cholesterol (HDL-C) and HDL functionality. Although policosanol supplementation also ameliorated liver function in animal models, it has not been reported in a human clinical study, particularly with a 20 mg doage of policosanol. In the current study, twelve-week consumption of Cuban policosanol (Raydel^®) significantly enhanced the hepatic functions, showing remarkable decreases in hepatic enzymes, blood urea nitrogen, and glycated hemoglobin. From the human trial with Japanese participants, the policosanol group (n = 26, male 13/female 13) showed a remarkable decrease in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) from baseline up to 21% (p = 0.041) and 8.7% (p = 0.017), respectively. In contrast, the placebo group (n = 26, male 13/female 13) showed almost no change or slight elevation. The policosanol group showed a 16% decrease in γ-glutamyl transferase (γ-GTP) at week 12 from the baseline (p = 0.015), while the placebo group showed a 1.2% increase. The policosanol group exhibited significantly lower serum alkaline phosphatase (ALP) levels at week 8 (p = 0.012), week 12 (p = 0.012), and after 4-weeks (p = 0.006) compared to those of the placebo group. After 12 weeks of policosanol consumption, the ferric ion reduction ability and paraoxonase of serum were elevated by 37% (p < 0.001) and 29% (p = 0.004) higher than week 0, while placebo consumption showed no notable changes. Interestingly, glycated hemoglobin (HbA_1c) in serum was lowered significantly in the policosanol group 4 weeks after consumption, which was approximately 2.1% (p = 0.004) lower than the placebo group. In addition, blood urea nitrogen (BUN) and uric acid levels were significantly lower in the policosanol group after 4 weeks: 14% lower (p = 0.002) and 4% lower (p = 0.048) than those of the placebo group, respectively. Repeated measures of ANOVA showed that the policosanol group had remarkable decreases in AST (p = 0.041), ALT (p = 0.008), γ-GTP (p = 0.016), ALP (p = 0.003), HbA_1c (p = 0.010), BUN (p = 0.030), and SBP (p = 0.011) from the changes in the placebo group in point of time and group interaction. In conclusion, 12 weeks of 20 mg consumption of policosanol significantly enhanced hepatic protection by lowering the serum AST, ALT, ALP, and γ-GTP via a decrease in glycated hemoglobin, uric acid, and BUN with an elevation of serum antioxidant abilities. These results suggest that improvements in blood pressure by consumption of 20 mg of policosanol (Raydel^®) were accompanied by protection of liver function and enhanced kidney function.

Beneficial Effect of Cuban Policosanol on Blood Pressure and Serum Lipoproteins Accompanied with Lowered Glycated Hemoglobin and Enhanced High-Density Lipoprotein Functionalities in a Randomized, Placebo-Controlled, and Double-Blinded Trial with Healthy Japanese

This study evaluated the efficacy and safety of 20 mg of Cuban policosanol in blood pressure (BP) and lipid/lipoprotein parameters of healthy Japanese subjects via a placebo-controlled, randomized, and double-blinded human trial. After 12 weeks of consumption, the policosanol group showed significantly lower BP, glycated hemoglobin (HbA1c), and blood urea nitrogen (BUN) levels. The policosanol group also showed lower aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl transferase (γ-GTP) levels at week 12 than those at week 0: A decrease of up to 9% (p < 0.05), 17% (p < 0.05), and 15% (p < 0.05) was observed, respectively. The policosanol group showed significantly higher HDL-C level and HDL-C/TC (%), approximately 9.5% (p < 0.001) and 7.2% (p = 0.003), respectively, than the placebo group and a difference in the point of time and group interaction (p < 0.001). In lipoprotein analysis, the policosanol group showed a decrease in oxidation and glycation extent in VLDL and LDL with an improvement of particle shape and morphology after 12 weeks. HDL from the policosanol group showed in vitro stronger antioxidant and in vivo anti-inflammatory abilities. In conclusion, 12 weeks of Cuban policosanolconsumption in Japanese subjects showed significant improvement in blood pressure, lipid profiles, hepatic functions, and HbA1c with enhancement of HDL functionalities.

Enhancement of High-Density Lipoprotein (HDL) Quantity and Quality by Regular and Habitual Exercise in Middle-Aged Women with Improvements in Lipid and Apolipoprotein Profiles: Larger Particle Size and Higher Antioxidant Ability of HDL

Regular exercise, especially aerobic exercise, is beneficial for increasing serum high-density lipoprotein-cholesterol (HDL-C) levels in the general population. In addition to the HDL-C quantity, exercise enhances HDL functionality, antioxidants, and cholesterol efflux. On the other hand, the optimal intensity and frequency of exercise to increase HDL quantity and enhance HDL quality in middle-aged women need to be determined. The current study was designed to compare the changes in HDL quantity and quality among middle-aged women depending on exercise intensity, frequency, and duration; participants were divided into a sedentary group (group 1), a middle-intensity group (group 2), and a high-intensity group (group 3). There were no differences in anthropometric parameters among the groups, including blood pressure, muscle mass, and handgrip strength. Although there was no difference in serum total cholesterol (TC) among the groups, the serum HDL-C and apolipoprotein (apo)A-I levels remarkably increased to 17% and 12%, respectively, in group 3. Serum low-density lipoprotein-cholesterol (LDL-C), glucose, triglyceride, and the apo-B/apoA-I ratio were remarkably decreased in the exercise groups depending on the exercise intensity; group 3 showed 13%, 10%, and 45% lower LDL-C, glucose, and triglyceride (TG), respectively, than group 1. The hepatic and muscle damage parameter, aspartate aminotransferase (AST), was significantly decreased in the exercise groups, but high-sensitivity C-reactive protein (CRP), alanine aminotransferase (ALT), and γ-glutamyl transferase (γ-GTP) were similar in the three groups. In LDL, the particle size was increased 1.5-fold (p < 0.001), and the oxidation extent was decreased by 40% with a 23% lower TG content in group 3 than in group 1. In the exercise groups (groups 2 and 3), LDL showed the slowest electromobility with a distinct band intensity compared to the sedentary group (group 1). In HDL2, the particle size was 2.1-fold increased (p < 0.001) in the exercise group (group 3) with a 1.5-fold increase in TC content compared to that in group 1, as well as significantly enhanced antioxidant abilities, paraoxonase (PON) activity, and ferric ion reduction ability (FRA). In HDL3, the particle size was increased 1.2-fold with a 45% reduction in TG in group 3 compared to group 1. With increasing exercise intensity, apoA-I expression was increased in HDL2 and HDL3, and PON activity and FRA were enhanced (p < 0.001). In conclusion, regular exercise in middle-aged women is associated with the elevation of serum HDL-C and apoA-I with the enhancement of HDL quality and functionality and an increase in the TC content, particle size, and antioxidant abilities. With the reduction in TG and oxidized products in LDL and HDL, lipoproteins could have more anti-atherogenic properties through regular exercise in an intensity-dependent manner.

Anti-Inflammatory Activity of CIGB-258 against Acute Toxicity of Carboxymethyllysine in Paralyzed Zebrafish via Enhancement of High-Density Lipoproteins Stability and Functionality

Background: Hyperinflammation is frequently associated with the chronic pain of autoimmune disease and the acute death of coronavirus disease (COVID-19) via a severe cytokine cascade. CIGB-258 (Jusvinza®), an altered peptide ligand with 3 kDa from heat shock protein 60 (HSP60), inhibits the systemic inflammation and cytokine storm, but the precise mechanism is still unknown. Objective: The protective effect of CIGB-258 against inflammatory stress of N-ε-carboxymethyllysine (CML) was tested to provide mechanistic insight. Methods: CIGB-258 was treated to high-density lipoproteins (HDL) and injected into zebrafish and its embryo to test a putative anti-inflammatory activity under presence of CML. Results: Treatment of CML (final 200 μM) caused remarkable glycation of HDL with severe aggregation of HDL particles to produce dysfunctional HDL, which is associated with a decrease in apolipoprotein A-I stability and lowered paraoxonase activity. Degradation of HDL3 by ferrous ions was attenuated by a co-treatment with CIGB-258 with a red-shift of the Trp fluorescence in HDL. A microinjection of CML (500 ng) into zebrafish embryos resulted in the highest embryo death rate, only 18% of survivability with developmental defects. However, co-injection of CIGB-258 (final 1 ng) caused the remarkable elevation of survivability around 58%, as well as normal developmental speed. An intraperitoneal injection of CML (final 250 μg) into adult zebrafish resulted acute paralysis, sudden death, and laying down on the bottom of the cage with no swimming ability via neurotoxicity and inflammation. However, a co-injection of CIGB-258 (1 μg) resulted in faster recovery of the swimming ability and higher survivability than CML alone injection. The CML alone group showed 49% survivability, while the CIGB-258 group showed 97% survivability (p < 0.001) with a remarkable decrease in hepatic inflammation up to 50%. A comparison of efficacy with CIGB-258, Infliximab (Remsima®), and Tocilizumab (Actemra®) showed that the CIGB-258 group exhibited faster recovery and swimming ability with higher survivability than those of the Infliximab group. The CIGB-258 group and Tocilizumab group showed the highest survivability, the lowest plasma total cholesterol and triglyceride level, and the infiltration of inflammatory cells, such as neutrophils in hepatic tissue. Conclusion: CIGB-258 ameliorated the acute neurotoxicity, paralysis, hyperinflammation, and death induced by CML, resulting in higher survivability in zebrafish and its embryos by enhancing the HDL structure and functionality.

Long-Term Alcohol Consumption Caused a Significant Decrease in Serum High-Density Lipoprotein (HDL)-Cholesterol and Apolipoprotein A-I with the Atherogenic Changes of HDL in Middle-Aged Korean Women

Light-to-moderate alcohol drinking is associated with a low incidence of cardiovascular disease (CVD) via an elevation of high-density lipoproteins-cholesterol (HDL-C), particularly with the short-term supplementation of alcohol. However, there is no information on the change in the HDL qualities and functionalities between non-drinkers and mild drinkers in the long-term consumption of alcohol. This study analyzed the lipid and lipoprotein profiles of middle-aged Korean female non-drinkers, mild-drinkers, and binge-drinkers, who consumed alcohol for at least 10 years. Unexpectedly, the serum levels of HDL-C and apolipoprotein A-I (apoA-I) were decreased significantly depending on the alcohol amount; the binge-drinker group showed 18% and 13% lower HDL-C (p = 0.011) and apoA-I levels (p = 0.024), respectively, than the non-drinker group. Triglyceride (TG) and oxidized species, malondialdehyde (MDA), and low-density lipoproteins (LDL) levels were significantly elevated in the drinker groups. Interestingly, the binge-drinker group showed 1.4-fold higher (p = 0.020) cholesterol contents in HDL2 and 1.7-fold higher (p < 0.001) TG contents in HDL3 than those of the non-drinker group. The mild-drinker group also showed higher TG contents in HDL3 (p = 0.032) than the non-drinker group, while cholesterol contents were similar in the HDL3 of all groups. Transmission electron microscopy (TEM) showed that the non-drinker group showed a more distinct and clear particle shape of the LDL and HDL image with a larger particle size than the drinker group. Electrophoresis of LDL showed that the drinker group had faster electromobility with a higher smear band intensity and aggregation in the loading position than the non-drinker group. The HDL level of binge drinkers showed the lowest paraoxonase activity, the highest glycated extent, and the most smear band intensity of HDL and apoA-I, indicating that HDL quality and functionality were impaired by alcohol consumption. In conclusion, long-term alcohol consumption in middle-aged women, even in small amounts, caused a significant decrease in the serum HDL-C and apoA-I with atherogenic changes in LDL and HDL, such as an increase in TG and MDA content with a loss of paraoxonase activity.

Race and sex differences in HDL peroxide content among American adults with and without type 2 diabetes

Background

High-density lipoprotein (HDL) plays a critical role in protection against atherosclerosic and cardiovascular disease (ASCVD). In addition to contributing to clearing excess vascular cholesterol, HDL particles exhibit antioxidative functions, helping to attenuate adverse effects of oxidized low-density lipoproteins. However, these beneficial properties can be undermined by oxidative stress, inflammation, and unhealthy lifestyles and diet, as well as influenced by race and sex. Thus, when assessing cardiovascular risk, it is important to consider multifactorial aspects of HDL, including antioxidant activity rather than just total amount and type of HDL-cholesterol (HDL-C) particles. Because prior research showed HDL peroxide content (HDLperox) can be inversely associated with normal anti-oxidant HDL activity, elevated HDLperox may serve as a bioindicator of HDL dysfunction.

Methods

In this study, data from a large national cohort of Americans was utilized to determine the impact of sex, race, and diabetes status on HDLperox in middle-aged and older adults. A previously developed cell-free fluorometric method was utilized to quantify HDLperox in serum depleted of apo-B containing lipoproteins.

Results

In keeping with predictions, white men and diabetics exhibited HDLperox in the atypical upper range, suggestive of less functional HDL. White men had higher HDLperox levels than African American males (13.46 ± 6.10 vs. 10.88 ± 5.81, p < .001). There was also a significant main effect of type 2 diabetes (F(1,1901) = 14.9, p < .0001). Overall, African Americans evinced lower HDLperox levels, despite more obesity (10.3 ± 4.7 vs.11.81 ± 5.66 for Whites) suggesting that other aspects of lipid metabolism and psychosocial factors account for the higher prevalence of ASCVD in African Americans.

Conclusion

This research helps to provide a more comprehensive understanding of HDL function in a racially and metabolically diverse adult population. HDLperox content was significantly different in adults with type 2 diabetes, and distinctive in nondiabetic White males, and suggests other processes account for the higher prevalence of ASCVD among African Americans.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01608-4.

Ozonated Sunflower Oil Exerted Protective Effect for Embryo and Cell Survival via Potent Reduction Power and Antioxidant Activity in HDL with Strong Antimicrobial Activity

Ozonated sunflower oil (OSO) has potent antimicrobial effects, making it useful for topical applications to treat various skin diseases. On the other hand, regarding mechanistic insight, the antioxidant activity and cytoprotective effects of OSO are relatively less known. The current study compared the antioxidant ability and protective ability of OSO on cells and embryos against oxidative stress, such as H₂O₂ and oxidized low-density lipoproteins (oxLDL), to investigate its potential applications for wound-healing and anti-infection. OSO showed potent radical scavenging activity and ferric ion reduction ability that was up to 35% and 42% stronger than sunflower oil (SO) as a control in a dose-dependent manner. Measurement of the wavelength-maximum fluorescence (WMF) of high-density lipoproteins (HDL) revealed different behavior between OSO and SO treatment (final 1–16%). The OSO treatment caused a 12 nm red shift of Trp movement from 345 nm (at 0%) to 357 nm (at 16%), while SO caused a 12 nm blue shift of Trp movement from 345 nm (at 0%) to 333 nm (at 16%). The fluorescence intensity of HDL₃ was diminished remarkably by the OSO treatment by up to 80% from the initial level, while SO-treated HDL did not. OSO-treated HDL₃ showed slower electromobility with stronger band intensity and bigger HDL particle sizes than those of SO-treated HDL₃. The paraoxonase-1 (PON-1) activity of HDL₃ was enhanced by a co-treatment of OSO that was up to 2.3 times higher than HDL₃ alone in a dose-dependent manner, whereas the co-treatment of SO even inhibited the PON activity. The cell viability of RAW264.7 by the OSO treatment was 3.3 times higher than the SO treatment at a high dose range (from 10% to 50%, final). The OSO also exhibited more cytoprotective effects than SO in brain microglial cells in the presence of H₂O₂ (final 0.03%); treatment with OSO impeded apoptosis and reduced ROS production more than an SO treatment did. In the presence of H₂O₂ alone, 86 ± 5% of the embryos were killed by cell explosion after 24 h, but a co-treatment of OSO (final 4%) resulted in almost no embryo death (98% survivability). Injection of oxLDL (15 ng of protein) into zebrafish embryos caused acute death, while the co-injection of OSO (final 2%) resulted in 2.8 times higher survivability than oxLDL alone. These results suggest new effects of ozonated oil, such as enhanced antioxidant activity, more cytoprotective ability, and higher embryo protection against oxidative stress. These results may be useful in developing new methods for the quality control of ozonated oil and an assessment of its efficacy.

The Relevance of Noncoding DNA Variations of Paraoxonase Gene Cluster in Atherosclerosis-Related Diseases

The human paraoxonase (PON) gene cluster is comprised of three contiguous genes (PON1, PON2 and PON3) of presumably common origin coding three lactonases of highly similar structure and substrate specificity. The catalytic activity of PON proteins is directed toward artificial organophosphates and in physiological conditions toward thiolactones and oxidized phospholipids. Consequently, PON enzymes are regarded as an effective defense against oxidative stress and, as a result, against atherosclerosis development. Additionally, both PON's serum activity and its concentration are influenced by several polymorphic variations in coding and noncoding DNA regions of the PON gene cluster remaining in linkage disequilibrium. Hence, the genetic polymorphism of the PON gene cluster may contribute to atherosclerotic process progression or deceleration. In this review the authors analyzed the relevance of noncoding DNA polymorphic variations of PON genes in atherosclerosis-related diseases involving coronary and peripheral artery disease, stroke, diabetes mellitus, dementia and renal disease and concluded that the effect of PON gene cluster' polymorphism has a considerable impact on the course and outcome in these conditions. The following PON genetic variations may serve as additional predictors of the risk of atherosclerosis in selected populations and individuals.

Native High-Density Lipoproteins (HDL) with Higher Paraoxonase Exerts a Potent Antiviral Effect against SARS-CoV-2 (COVID-19), While Glycated HDL Lost the Antiviral Activity

Human high-density lipoproteins (HDL) show a broad spectrum of antiviral activity in terms of anti-infection. Although many reports have pointed out a correlation between a lower serum HDL-C and a higher risk of COVID-19 infection and progression, the in vitro antiviral activity of HDL against SARS-CoV-2 has not been reported. HDL functionality, such as antioxidant and anti-infection, can be impaired by oxidation and glycation and a change to pro-inflammatory properties. This study compared the antiviral activity of native HDL with glycated HDL via fructosylation and native low-density lipoproteins (LDL). After 72 h of fructosylation, glycated HDL showed a typical multimerized protein pattern with an elevation of yellowish fluorescence. Glycated HDL showed a smaller particle size with an ambiguous shape and a loss of paraoxonase activity up to 51% compared to native HDL. The phagocytosis of acetylated LDL was accelerated 1.3-fold by glycated HDL than native HDL. Native HDL showed 1.7 times higher cell viability and 3.6 times higher cytopathic effect (CPE) inhibition activity against SARS-CoV-2 than that of glycated HDL under 60 μg/mL (approximately final 2.2 μM) in a Vero E6 cell. Native HDL showed EC₅₀ = 52.1 ± 1.1 μg/mL (approximately final 1.8 μM) for the CPE and CC₅₀ = 79.4 ± 1.5 μg/mL (around 2.8 μM). The selective index (SI) of native HDL was calculated to be 1.52. In conclusion, native HDL shows potent antiviral activity against SARS-CoV-2 without cytotoxicity, while the glycation of HDL impairs its antiviral activity. These results may explain why patients with diabetes mellitus or hypertension are more sensitive to a COVID-19 infection and have a higher risk of mortality.

MirSNPs in clopidogrel metabolism genes predict cardiovascular disease risk: a case-control study and meta-analysis

Aim: The present study was conducted to decipher the inter-relationship of SNPs and miRNAs involved in pharmacogenomics of clopidogrel on predisposition to cardiovascular diseases (CVDs). Materials & methods: A case-control study was conducted on 410 cases and 386 controls to analyze the association of 13 mirSNPs on CVDs risk. Genotyping was performed by tetra-primer amplification refractory mutation system PCR and validated using Sanger DNA sequencing. miRNA expression analysis was performed using TaqMan assays. A meta-analysis was performed for PON1 rs662 with coronary artery disease. Results & conclusion: PON1 rs662, PON1 rs3917577, CYP3A5 rs15524, COL4A1 rs874204 and PTGIR rs1126510 polymorphisms showed association with CVDs. The miRNA hsa-miR-224-5p showed differential expression in the PON1 rs3917577 GG genotype. The meta-analysis showed the population-specific impact of PON1 rs662 on South Asian and Middle East populations.

Associations between nine candidate genetic polymorphisms with coronary heart disease : A meta-analysis

BACKGROUND

The aim of this study was to obtain a more accurate assessment of the potential association between nine genetic polymorphisms and the risk of coronary heart disease (CHD).

METHODS

A literature search was performed in PubMed, Embase, OVID, Web of Science, Wanfang, and Chinese National Knowledge Infrastructure (CNKI) databases to identify eligible studies. We analyzed the odds ratios (OR) and 95% confidence intervals (CI) to assess the strength of the associations.

RESULTS

A significant association was found between the PON1 -108C/T polymorphism and CHD risk (TT vs. CC: OR = 1.67, 95% CI = 1.14-2.47, p = 0.009; CT vs. CC: OR = 1.47, 95% CI = 1.17-1.85, p = 0.001; [TT + CT] vs. CC: OR = 1.56, 95% CI = 1.18-2.06, p = 0.002; T allele vs. C allele: OR = 1.28, 95%CI = 1.06-1.54, p = 0.011). There was a significant association between the hOGG1 +1245C/G polymorphism and CHD (GG vs. CC: OR = 2.33, 95% CI: 1.19-4.56, p = 0.014; CG vs. CC: OR = 1.36, 95% CI: 1.01-1.83, p = 0.046; [GG + CG] vs. CC: OR = 1.46, 95% CI: 1.10-1.94, p = 0.010; GG vs. [CC+CG]: OR = 2.11, 95% CI: 1.08-4.10, p = 0.028; G allele vs. C allele: OR = 1.45, 95% CI: 1.14-1.84, p = 0.002). The results also showed a statistically significant association of the SCARB1 +1050C/T polymorphism with CHD (TT vs. CC: OR = 1.30, 95% CI = 1.04-1.62, p = 0.022). Meta-analyses of the other six polymorphisms suggested a lack of any association with CHD risk.

CONCLUSION

Our results show that the susceptibility to CHD was associated with three polymorphisms: PON1 -108C/T, hOGG1 +1245C/G, and SCARB1 +1050C/T.

Associations of the PON1 rs662 polymorphism with circulating oxidized low-density lipoprotein and lipid levels: a systematic review and meta-analysis

BACKGROUND

Several meta-analyses have demonstrated that the rs662 polymorphism in Paraoxonase 1 gene (PON1) gene is associated with coronary heart disease (CHD). However, it is still uncertain whether this polymorphism is associated with the plasma levels of oxidized low-density lipoprotein (Ox-LDL) and lipids. This meta-analysis is aimed to clarify the relationships between the rs662 polymorphism and plasma levels of Ox-LDL and lipids.

METHODS

By searching in PubMed, Google Scholar, Web of Science, Cochrane Library, Wanfang, VIP and CNKI databases, 5 studies (1369 subjects) and 85 studies (46,740 subjects) were respectively identified for Ox-LDL association analysis and lipid association analysis. Standardized mean difference (SMD) was used to estimate the effects of the rs662 polymorphism on plasma Ox-LDL and lipid levels.

RESULTS

The carriers of the variant R allele had higher levels of Ox-LDL (SMD = 0.23, 95% CI = 0.10-0.36, P <  0.01), triglyceride (TG) (SMD = 0.06, 95% CI = 0.01-0.11, P = 0.02), total cholesterol (TC) (SMD = 0.04, 95% CI = 0.00-0.07, P = 0.05) and low-density lipoprotein cholesterol (LDL-C) (SMD = 0.04, 95% CI = 0.00-0.08, P = 0.04) than the non-carriers.

CONCLUSIONS

This meta-analysis suggests that the association between the PON1 rs662 polymorphism and CHD may partly be mediated by abnormal Ox-LDL and lipid levels caused by the R allele.

Serum paraoxonase-1 activity is associated with light to moderate alcohol consumption: the PREVEND cohort study

Background

Paraoxonase-1 (PON-1) is a high-density lipoprotein (HDL)-associated enzyme with antioxidative properties, which may protect against the development of cardiovascular disease. Alcohol consumption increases HDL cholesterol, but the extent to which alcohol consumption gives rise to higher serum PON-1 activity is uncertain.

Objective

In a population-based study, we determined the relation of serum PON-1 activity with alcohol consumption when taking account of HDL cholesterol and apolipoprotein A-I (apoA-I), its major apolipoprotein.

Design

A cross-sectional study was performed in 8224 participants of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) cohort. Alcohol consumption was categorized as 1) no/rarely (25.3%); 2) 0.1-10 g/d (49.3%); 3) 10-30 g/d (20.1%); and 4) >30 g/d (5.2%) with 1 drink equivalent to 10 g alcohol. Serum PON-1 activity was measured as its arylesterase activity (phenyl acetate as substrate).

Results

Median serum PON-1 activity was 50.8, 53.1, 54.4, and 55.7 U/L in the 4 categories of alcohol consumption, respectively (P < 0.001). Its increase paralleled the increments in HDL cholesterol and apoA-I. Notably, there was no further increase in PON-1 activity, HDL cholesterol, and apoA-I when alcohol consumption was increased from 10-30 g/d to >30 g/d. Multivariable linear regression analysis demonstrated that PON-1 activity was related to alcohol consumption independently from clinical covariates, high sensitivity C-reactive protein, and lipid concentrations, including HDL cholesterol (P < 0.001 for each category of alcohol consumption with no alcohol consumption as the reference category). Notably, as inferred from standardized β-coefficients, there was no difference in PON-1 activity between 10-30 g alcohol/d and >30 g alcohol/d.

Conclusions

Alcohol consumption is associated with an increase in serum PON-1 activity, but its effect seems to reach a plateau with alcohol consumption of 10-30 g/d.

Paraoxonase-1 is a better indicator than HDL of Atherosclerosis - A pilot study in North Indian population

OBJECTIVES

The present study aims to evaluate the levels of HDL and Paraoxonase-1 (PON1) and their correlation in atherosclerotic patients with and without diabetic mellitus (DM) as well as in control subjects in Northern Indian population.

MATERIALS AND METHODS

We analyzed lipid profiles and Serum PON1 levels by automated analyzer and ELISA, respectively. Study subjects (N = 150) were divided in three groups; Group I: Atherosclerotic patients without DM (N = 50), Group II: Atherosclerotic patients with DM (N = 50); Group III: Controls (N = 50).

RESULTS

We found a significantly (p < 0.0001) low levels of HDL-C in Group I (32.2 ± 7.3) and Group II (36.9 ± 11.5) as compared to Group III (41.0 ± 7.1). PON-1 levels were also significantly lower in Group I (60.1 ± 10.5) and Group II (50.0 ± 13.9) when compared to Group III (95.0 ± 12.0). We observed a significant correlation (r = 0.59, p < 0.001) between the levels of PON1 and HDL-C in study subjects.

CONCLUSIONS

The reduced levels of HDL and PON-1 and their significant correlation in CAD patients may be associated with the pathogenesis of this disease. Considering HDL as a dependent variable, Paraoxonase-1 is the most important parameter contributing to the total variation in HDL in CAD.

Relation of Paraoxonase 1 Activity with Biochemical Variables, Brachial Artery Intima-Media Thickness in Patients with Diabetes with or without Obesity

AIM

The sodium-sparing effect of insulin leads to increase in total sodium pool of the body which is a chronic stimulus for atrial natriuretic peptide (ANP). In our study we aimed to determine the relationship between ANP and microvascular complications of diabetes.

METHODS

60 patients, 30-70 years old, with the diagnosis of type 2 diabetes mellitus (DM) are enrolled into the study. Patients with a chronic disease other than DM are excluded. Blood samples for routine biochemical tests are taken after at least 12 h fasting at 8-9 am. Blood samples for glucose and insulin levels are taken 2 h after a standard meal. Blood tubes with EDTA are used for ANP levels. The microvascular complications of the patients are evaluated.

RESULTS

32 of the patients had microvascular complications. Age, BMI, waist and hip circumferences, and ANP levels were significantly higher in the group with microvascular complications. There were no significant differences in waist-to-hip ratio, blood glucose, HbA1c, fasting insulin, postprandial insulin, fasting HOMA, postprandial HOMA as well as sodium, potassium, magnesium, calcium and lipid levels between the two groups. When the relationship between ANP and obesity, retinopathy, neuropathy, nephropathy, diabetes time, HbA1c, or sex are evaluated separately, the only significant parameters related to ANP were obesity and retinopathy.

CONCLUSION

In our study we have found that there was a significant relationship between ANP levels and microvascular complications of diabetes. Future studies are needed to show if ANP is the stimulus of microvascular complication development/progression or only an epiphenomenon.

Serum paraoxonase-1 activity is inversely related to free thyroxine in euthyroid subjects: The PREVEND Cohort Study

BACKGROUND

Low-normal thyroid function within the euthyroid range has been suggested to enhance atherosclerosis susceptibility. Paraoxonase-1 (PON-1) may protect against atherosclerotic cardiovascular disease development by attenuating oxidative stress. We evaluated relationships of PON-1 with thyroid stimulating hormone (TSH), free T₄ , free T₃ , lipids and apolipoprotein (apo)A-I in euthyroid subjects, and assessed whether such relationships are modified in the context of the metabolic syndrome (MetS).

MATERIALS AND METHODS

Serum PON-1 activity (arylesterase activity), TSH, free T₄ , free T₃ , lipids and apoA-I was measured in 2206 euthyroid subjects (aged 28-75 years; 1138 men (age 49 ± 13 years) and 1068 women (age 46 ± 12 years), recruited from the general population (PREVEND cohort).

RESULTS

In age- and sex-adjusted analysis, PON-1 activity (divided into tertiles) was positively related to TSH (β = -0.045, P = .036) and inversely to free T₄ (β = -0.042, P = .050) but not to free T₃ (β = -0.027, P = .20). PON-1 activity was positively related to total cholesterol, non-HDL cholesterol and triglycerides, as well as to HDL cholesterol and apoA-I (P < .01 to <.001). The inverse relationship of PON-1 activity with free T₄ remained present after adjustment for lipids and other potential confounders (β = -0.066, P = .002), but the positive relationship with TSH lost significance (β = 0.034, P = .11). The inverse relationship of PON-1 activity with free T₄ was not different in subjects with vs without MetS (P = .94), nor modified by the presence of its individual components (P ≥ .22 for each).

CONCLUSIONS

Serum PON-1 activity is inversely associated with free T₄ in euthyroid subjects, suggesting that low-normal thyroid function may affect PON-1 regulation.

Dysfunctional HDL in diabetes mellitus and its role in the pathogenesis of cardiovascular disease

Coronary artery disease, the leading cause of death in the developed and developing countries, is prevalent in diabetes mellitus with 68% cardiovascular disease (CVD)-related mortality. Epidemiological studies suggested inverse correlation between HDL and CVD occurrence. Therefore, low HDL concentration observed in diabetic patients compared to non-diabetic individuals was thought to be one of the primary causes of increased risks of CVD. Efforts to raise HDL level via CETP inhibitors, Torcetrapib and Dalcetrapib, turned out to be disappointing in outcome studies despite substantial increases in HDL-C, suggesting that factors beyond HDL concentration may be responsible for the increased risks of CVD. Therefore, recent studies have focused more on HDL function than on HDL levels. The metabolic environment in diabetes mellitus condition such as hyperglycemia-induced advanced glycation end products, oxidative stress, and inflammation promote HDL dysfunction leading to greater risks of CVD. This review discusses dysfunctional HDL as one of the mechanisms of increased CVD risks in diabetes mellitus through adversely affecting components that support HDL function in cholesterol efflux and LDL oxidation. The dampening of reverse cholesterol transport, a key process that removes cholesterol from lipid-laden macrophages in the arterial wall, leads to increased risks of CVD in diabetic patients. Therapeutic approaches to keep diabetes under control may benefit patients from developing CVD.

Incident type 2 diabetes is associated with HDL, but not with its anti-oxidant constituent - paraoxonase-1: The prospective cohort PREVEND study

OBJECTIVE

High-density lipoprotein cholesterol (HDL-C) is an established risk marker for cardiovascular disease and consistently associated with type 2 diabetes risk. Serum paraoxonase-1 (PON-1) - an anti-oxidant constituent of HDL - is inversely associated with cardiovascular disease risk, but its relationship with incident type 2 diabetes is uncertain. We aimed to investigate the prospective association between PON-1 and type 2 diabetes risk.

METHODS

PON-1 was measured as its arylesterase activity at baseline in the Prevention of Renal and Vascular End-stage Disease (PREVEND) prospective study of 5947 predominantly Caucasian participants aged 28-75years with no pre-existing diabetes, that recorded 500 type 2 diabetes cases during a median follow-up of 11.2years.

RESULTS

Serum PON-1 was positively correlated with HDL-C (r=0.17; P<0.001). In analyses adjusted for conventional diabetes risk factors, the hazard ratio (95% CI) for type 2 diabetes per 1 standard deviation increase in PON-1 was 1.07 (0.98 to 1.18; P=0.13), which remained non-significant (1.02 (0.93 to 1.12) P=0.65) after additional adjustment for potential confounders. The association was unchanged on further adjustment for HDL-C (1.05 (0.96 to 1.15; P=0.29). However, in subsidiary analyses in the same set of participants, serum HDL-C concentration was inversely and independently associated with risk of type 2 diabetes.

CONCLUSIONS

Incident type 2 diabetes is associated with HDL cholesterol but not with its anti-oxidant constituent - PON-1 - in a large cohort of apparently healthy men and women. The current data question the importance of PON-1 activity for the development of diabetes.

Effects of paraoxonase 1 gene polymorphisms on heart diseases: Systematic review and meta-analysis of 64 case-control studies

BACKGROUND

Associations between paraoxonase 1 (PON1) gene polymorphisms and heart diseases (HD) risk remain inconsistent. In order to obtain address this issue we performed a meta-analysis to assess the association between the L55M and Q192R polymorphisms of PON1 gene and heart diseases risk.

METHODS

Relevant studies were enrolled by searching databases systematically. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate the strength of association. Subgroup analyses were conducted for diagnostic and ethnicity. The heterogeneity among each of the studies was calculated by using Cochran Qtest and the inconsistency index (I), and Begg's funnel plot and Egger's tests were performed to evaluate publication bias.

RESULT

Sixty four studies involving a total of 19,715 cases and 33,397 controls were included in this meta-analysis. We found that the L55M polymorphism showed a significant association with heart diseases in Europeans (OR 1.44, 95%CI 1.33-1.56) and Asians (OR 1.18, 95%CI 1.03-1.35). This meta-analysis also showed a protective association of Q192R polymorphism with HD in Asian (OR 0.49, 95%CI 0.37-0.66) and African populations (OR 0.67, 95%CI 0.53-0.84). The 192R allele significantly decreased the risk of myocardial infarction (OR 0.75, 95%CI 0.57-0.99) and coronary artery disease (OR 0.91, 95%CI 0.84-0.98); however, individuals with 192Q allele had a markedly increased risk of coronary artery disease development (OR 1.38, 95%CI 1.22-1.56).

CONCLUSION

This study demonstrated that the genetic risk for heart diseases is associated with the PON1 gene polymorphisms. L55M polymorphism is a risk factor and Q192R polymorphism is protective in certain populations. It is worth noting that the 192Q allele may be a risk factor to develop coronary artery disease.

The therapeutic efficacy of intensive medical therapy in ameliorating high-density lipoprotein dysfunction in subjects with type two diabetes

BACKGROUND

To determine whether 12 months of intensive medical therapy (IMT) improves HDL functionality parameters in subjects with type II diabetes (T2D).

METHODS

Retrospective, randomized, and controlled 12-month IMT intervention trial that enrolled 13-subjects with T2D (age 51- years, fasting glucose 147 mg/dL, body mass index [BMI] 36.5 kg/m(2)) and nine healthy control (46-years, fasting glucose 90 mg/dL, BMI 26.5 kg/m2). Subjects with T2D underwent IMT and HDL functionality measures (pro-inflammatory index of high-density lipoprotein (pHDL)), paraoxonase one (PON1), ceruloplasmin (Cp), and myeloperoxidase (MPO) activity were performed on samples at baseline and at 12-months following IMT.

RESULTS

At baseline, pHDL index was significantly higher in subjects with T2D (p < 0.001) and apolipoprotein A-1 levels were significantly lower (p = 0.013) vs.

CONTROLS

After 12-months, there was a trend for improved pHDL activity (p = 0.083), as indicated by intent-to-treat analysis, but when the non-adherent subject was omitted (per-protocol), significant attenuations in pHDL activity (p = 0.040) were noted; Δ pHDL activity at 12-months was associated with Δ weight (r = 0.62, p = 0.032) and Δ fasting glucose (r = 0.65, p = 0.022). Moreover, PON1 activity significantly improved (p < 0.001). The aforementioned occurred in association with improvements in inflammatory markers (i.e., C-reactive protein & tumor necrosis factor), hemoglobin A1C, fasting glucose, triglycerides, high-density lipoprotein levels and adipokines.

CONCLUSION

IMT ameliorates pHDL index and significantly improves anti-oxidative function, as measured by PON1. Improvements in weight and fasting glucose mediated the decrease in pHDL index. Pharmacological aids and lifestyle modification are required to improve cardiovascular risk factors, subsequent mortality risk, and promote T2D remission. Application of either form of therapy alone may only have relatively miniscule effects on the aforementioned factors, in relation to the aggregate.

Virgin Coconut Oil and its Cardiovascular Health Benefits

Cardiovascular disease (CVD) is known as the number one cause of death worldwide. It is associated with huge health care costs and loss of productivity in the population. Poor diet is an important risk factor in CVD. Diet rich in polyunsaturated fatty acids, such as virgin coconut oil (VCO), has been associated with a reduced risk of CVD. This systematic review focused on studies that reported the association between VCO and the biochemical measurements associated with CVD. These studies conclude that VCO shows promising effects in improving the biochemical derangements associated with CVD, thus lowering the CVD risk. However, most of these studies were performed in animals with very limited data from human. Future investigations are needed to examine the health benefits of VCO in human intervention studies.

Interaction between polyphenols intake and PON1 gene variants on markers of cardiovascular disease: a nutrigenetic observational study

BACKGROUND

Paraoxonase 1 (PON1) gene polymorphisms and polyphenols intake have been reported independently associated to lipid profile and susceptibility to atherosclerosis and cardiovascular disease. However, the interaction between these factors remains to be investigated. We performed an observational nutrigenetic study to examine whether the interaction between polyphenols and anthocyanins intake and PON1 genetic variants can modulate biomarkers of cardiovascular health in an Italian healthy population.

METHODS

We recruited 443 healthy volunteers who participated in the EC funded ATHENA project (AnThocyanin and polyphenols bioactive for Health Enhancement through Nutritional Advancement). Data collection included detailed demographic, clinical, dietary, lifestyle, biochemical and genetic data. Polyphenols and anthocyanins intake was measured by 24 h dietary recall repeated three times a year in order to get seasonal variations. We tested the interaction between 18 independent tagging SNPs in PON1 gene and polyphenols intake on HDL, LDL, cholesterol, triglycerides and atherogenic index of plasma.

RESULTS

Without considering the genetic background, we could not observe significant differences in the lipid profile between high and low polyphenols and anthocyanins intake. Using a nutrigenetic approach, we identified protective genotypes in four independent polymorphisms that, at Bonferroni level (p ≤ 0.0028), present a significant association with increased HDL level under high polyphenols and anthocyanins intake, compared to risk genotypes (rs854549, Beta = 4.7 per C allele; rs854552, Beta = 5.6 per C allele; rs854571, Beta = 3.92 per T allele; rs854572, Beta = 3.94 per C allele).

CONCLUSIONS

We highlight the protective role of genetic variants in PON1 towards cardiovascular risk under high polyphenols and anthocyanins consumption. PON1 variants could represent novel biomarkers to stratify individuals who might benefit from targeted dietary recommendation for health promotion and strategies of preventive medicine.

Effect of Red Yeast Rice and Coconut, Rice Bran or Sunflower Oil Combination in Rats on Hypercholesterolemic Diet

INTRODUCTION

Dietary supplements provide a novel population based health approach for treating hyperlipidemias. Red yeast rice is known to have lipid lowering effects. Combination of red yeast rice with various oils is taken by different population around the world.

AIM

In this present work, we aimed to compare the effects of red yeast rice with different oil (coconut, rice bran and sunflower oil) supplementations on lipid levels and oxidative stress in rats fed on hypercholesterolemic diet.

MATERIALS AND METHODS

A Randomized controlled study was conducted on 28 male Sprague Dawley rats. It included 4 arms-Control arm (hypercholesterolemic diet), Test arm A (hypercholesterolemic diet +Red yeast rice + Rice bran oil), arm B (hypercholesterolemic diet +Red yeast rice + Coconut oil) and arm C (hypercholesterolemic diet +Red yeast rice + Sunflower oil). At the end of one month, serum cholesterol, triglycerides, MDA and paraoxonase was measured. The mean values of analytes between the different groups were compared using student 't-' test.

RESULTS

The rats fed with red yeast rice and rice bran oil combination showed significantly lower levels of serum cholesterol, triglycerides and MDA when compared to the controls. The serum paraoxonase levels were significantly higher in this group when compared to the controls. The rats fed with red yeast rice and coconut oil combination showed significantly lower serum cholesterol and MDA levels when compared to the controls. The mean triglyceride and paraoxonase levels did not show any statistically significant difference from the controls. The rats on red yeast rice and sunflower oil combination did not show any statistically significant difference in the lipid levels and oxidative stress parameters.

CONCLUSION

The food combination which had best outcome in preventing the development of hyperlipidemia and oxidative stress in rats fed with hypercholesterolemic diet was red yeast rice and rice bran oil. Combining red yeast rice with coconut oil and sunflower oil gave suboptimal benefits.

Strawberries Added to the Usual Diet Suppress Fasting Plasma Paraoxonase Activity and Have a Weak Transient Decreasing Effect on Cholesterol Levels in Healthy Nonobese Subjects

OBJECTIVE

Strawberries can improve oxidants-antioxidants balance and reduce some cardiovascular risk factors in obese subjects. Paraoxonase-1 (PON-1) is a high-density lipoprotein-associated enzyme with antioxidant properties that can protect from coronary artery disease in humans. We examined the effect of strawberry consumption on plasma PON-1 activity and lipid profile in healthy nonobese subjects.

METHODS

Thirty-one subjects (body mass index [BMI] 24.4 ± 4.0 kg/m(2)) on their usual diet consumed 500 g of strawberry pulp daily for 30 days (first course) and after a 10-day washout the cycle was repeated (second course). Fasting blood and spot morning urine samples were collected before, during, and after each strawberry course (8 time points) for determination of paraoxonase and arylesterase PON-1 activities and lipid profile. Twenty subjects served as controls with respect to cholesterol and PON-1 activities changes over the study period.

RESULTS

Strawberries decreased mean plasma paraoxonase PON-1 activity and this effect was more evident after the second course (by 11.6%, p < 0.05) than after the first course (5.4%, p = 0.06), whereas arylesterase activity was constant. Strawberries altered total cholesterol levels (p < 0.05) with a tendency to transiently decrease it (by 5.1%) only after 15 days of the first course. Triglycerides and high- and low-density lipoprotein cholesterol did not change in response to fruit consumption. No changes in PON-1 activities and lipid profile were noted in controls. Paraoxonase correlated with arylesterase activity (ƿ from 0.33 to 0.46 at the first 7 time points, p < 0.05). This association disappeared at the end of study (ƿ = 0.07) when the strongest inhibition of paraoxonase was noted.

CONCLUSIONS

Supplementation of the usual diet with strawberries decreased paraoxonase PON-1 activity and did not improve lipid profiles in healthy nonobese subjects. Further studies are necessary to establish the clinical significance of paraoxonase suppression and to define a group of healthy subjects who can benefit from strawberry consumption with respect to cholesterol levels.

Paraoxonase-1 activity is positively related to phospholipid transfer protein activity in type 2 diabetes mellitus: Role of large HDL particles

OBJECTIVES

High density lipoprotein (HDL)-associated paraoxonase-1 (PON-1) exerts anti-oxidative properties, whereas phospholipid transfer protein (PLTP) is able to convert mature HDL into larger and smaller HDL particles. Here we tested associations of PON-1 with PLTP in type 2 diabetes mellitus (T2DM), a condition characterized by lower PON-1 activity and higher PLTP activity.

DESIGN AND METHODS

Serum PON-1 (arylesterase activity), plasma PLTP activity (liposome-vesicle HDL system), and (apo)lipoproteins were measured in 81 T2DM subjects (mean age 59±9years; 31 women; no insulin treatment). In 48 participants, HDL subfractions were measured by nuclear magnetic resonance spectroscopy.

RESULTS

In univariate correlation analysis, PON-1 activity was positively related to PLTP activity (r=0.348, p=0.001). PLTP activity was positively related to blood pressure, body mass index and triglycerides, whereas PON-1 activity was positively to HDL cholesterol and apoA-I (p<0.05 to <0.01 for each). Both PLTP activity and PON-I activity were positively related to large HDL particles (r=0.379, p=0.008 and r=0.411, p=0.004, respectively). In multivariable linear regression analysis, PON-1 activity was associated with PLTP activity independent of clinical covariates and HDL cholesterol or apoA-I (β=0.340, p=0.001 and β=0.320, p=0.003, respectively). The association of PON-1 activity with PLTP activity was lost in analysis which included large HDL particles (large HDL: β=0.411, p=0.004).

CONCLUSIONS

PON-1 activity is positively related to PLTP activity in T2DM, raising the possibility that PLTP could act to maintain PON-1. This association may in part be attributable to a common relationship of PON-1 and PLTP with large HDL particles.

p.Q192R SNP of PON1 seems not to be Associated with Carotid Atherosclerosis Risk Factors in an Asymptomatic and Normolipidemic Brazilian Population Sample

BACKGROUND

Evidences suggest that paraoxonase 1 (PON1) confers important antioxidant and anti-inflammatory properties when associated with high-density lipoprotein (HDL).

OBJECTIVE

To investigate the relationships between p.Q192R SNP of PON1, biochemical parameters and carotid atherosclerosis in an asymptomatic, normolipidemic Brazilian population sample.

METHODS

We studied 584 volunteers (females n = 326, males n = 258; 19-75 years of age). Total genomic DNA was extracted and SNP was detected in the TaqMan® SNP OpenArray® genotyping platform (Applied Biosystems, Foster City, CA). Plasma lipoproteins and apolipoproteins were determined and PON1 activity was measured using paraoxon as a substrate. High-resolution β-mode ultrasonography was used to measure cIMT and the presence of carotid atherosclerotic plaques in a subgroup of individuals (n = 317).

RESULTS

The presence of p.192Q was associated with a significant increase in PON1 activity (RR = 12.30 (11.38); RQ = 46.96 (22.35); QQ = 85.35 (24.83) μmol/min; p < 0.0001), HDL-C (RR= 45 (37); RQ = 62 (39); QQ = 69 (29) mg/dL; p < 0.001) and apo A-I (RR = 140.76 ± 36.39; RQ = 147.62 ± 36.92; QQ = 147.49 ± 36.65 mg/dL; p = 0.019). Stepwise regression analysis revealed that heterozygous and p.192Q carriers influenced by 58% PON1 activity towards paraoxon. The univariate linear regression analysis demonstrated that p.Q192R SNP was not associated with mean cIMT; as a result, in the multiple regression analysis, no variables were selected with 5% significance. In logistic regression analysis, the studied parameters were not associated with the presence of carotid plaques.

CONCLUSION

In low-risk individuals, the presence of the p.192Q variant of PON1 is associated with a beneficial plasma lipid profile but not with carotid atherosclerosis.

Paraoxonase 1 activity and lipid profile in schizophrenic patients

OBJECTIVE

This study aimed to investigate the variations of paraoxonase 1 (PON1) activity and lipid profile in patients with schizophrenia and the association of this activity with the sociodemographic, clinical and therapeutical characteristics of this population.

PATIENTS AND METHODS

Our cross-sectional study included 140 schizophrenic patients and 119 control subjects aged respectively 37.3±10.4 and 41.4±10 years. PON1 activity was determined using Konelab 30™ equipment (Thermo Electron Corporation). Plasma total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (c-HDL) and low-density lipoprotein cholesterol (c-LDL) concentrations were determined using Cobas 6000™ (Roche Diagnostics), apolipoproteins (ApoA1, ApoB) and lipoprotein (a) (Lp(a)) were determined using Integra 400 plus (Roche Diagnostics).

RESULTS

Compared to controls, patients had no significant decrease of PON1 activity and significantly lower ApoA1, c-HDL levels, and significantly higher levels of TG, ApoB, Lp(a) and TC/c-HDL and ApoB/ApoA1 ratios. Furthermore, PON1 activity was correlated with TG/c-HDL ratio. The lowest PON1 activity was noted in obese patients, in paranoid sub-type and in patients treated with combination of typical and atypical antipsychotics without significant difference. Moreover, it was associated with gender and cigarette smoking but not with alcohol consumption status.

CONCLUSION

Schizophrenic patients had a decrease in PON1 activity and perturbations in their lipid profiles that contribute to increase the risk of cardiovascular diseases. In addition, our results revealed that there was no association between the decrease of PON1 activity and any demographic or clinical characteristics. Therefore, such patients require specific care, particularly with regard to their lipid profile.

Serum paraoxonase-1 activity is more closely related to HDL particle concentration and large HDL particles than to HDL cholesterol in Type 2 diabetic and non-diabetic subjects

OBJECTIVES

We determined relationships of the anti-oxidative enzyme, paraoxonase-1 (PON-1), with high density lipoprotein (HDL) subfractions, and tested whether these relationships are stronger than those with HDL cholesterol and apolipoprotein A-I (apoA-I) in subjects with and without type 2 diabetes mellitus (T2DM).

DESIGN AND METHODS

Serum PON-1 (arylesterase activity) and HDL subfractions (nuclear magnetic resonance spectroscopy) were determined in 67 T2DM patients and in 56 non-diabetic subjects.

RESULTS

PON-1 activity, HDL cholesterol and apoA-I were decreased in T2DM (all p<0.05). The HDL particle concentration was unaltered, but large HDL particles, medium HDL particles and HDL particle size were decreased, whereas small HDL particles were increased in T2DM (all p<0.05). PON-1 was more closely related to HDL cholesterol than to apoA-I (p=0.001). In turn, the positive relationship of PON-1 with the HDL particle concentration and with large HDL particles was stronger than that with HDL cholesterol (both p<0.01). The inverse relationship of PON-1 with T2DM was only modestly attenuated by HDL cholesterol or HDL particle characteristics.

CONCLUSIONS

PON-1 activity is more closely related to the HDL particle concentration or large HDL particles than to HDL cholesterol. Impaired PON-1 activity in T2DM is not to a considerable extent explained by altered HDL subfraction levels.

Reduced paraoxonase 1 activity as a marker for severe coronary artery disease

Paraoxonase-1 (PON1), a high-density-lipoprotein- (HDL-) associated enzyme, has the potential to protect against atherogenesis. We examine the relationships between plasma PON1 activity and the progression of atherosclerosis as well as coronary artery disease (CAD). Fasting blood samples were collected from female apolipoprotein E-deficient (apoE(-/-)) mice and 149 patients undergoing coronary angiography for the biochemical parameters measurement. The severity of CAD was defined using angiographic Gensini score (GSS). Compared to 3-month-old apoE(-/-) mice, aged mice had significantly lower PON1 activity, which is negatively correlated with the size of atherosclerotic lesion and plasma interleukin-6 (IL-6) and tumor necrosis factor α (TNF- α ) levels. In study patients, PON1 activity was correlated with age, sex, and HDL-cholesterol, apolipoprotein AI, and high-sensitivity C-reactive protein (hs-CRP) levels and was significantly lower in CAD group than that in non-CAD control group. Interestingly, PON1 activity in severe CAD group (GSS > 40) was further significantly reduced compared to those in mild and moderate subgroups (GSS  ≤ 40) (P < 0.01). There is a significant correlation between PON1 activity and the severity of CAD as assessed by GSS (r = -0.393, P < 0.001). PON1 activity may be a potential biomarker for the severity of CAD.

Anti-inflammatory mechanisms of apolipoprotein A-I mimetic peptide in acute respiratory distress syndrome secondary to sepsis

Acute respiratory distress syndrome (ARDS) due to sepsis has a high mortality rate with limited treatment options. High density lipoprotein (HDL) exerts innate protective effects in systemic inflammation. However, its role in ARDS has not been well studied. Peptides such as L-4F mimic the secondary structural features and functions of apolipoprotein (apo)A-I, the major protein component of HDL. We set out to measure changes in HDL in sepsis-mediated ARDS patients, and to study the potential of L-4F to prevent sepsis-mediated ARDS in a rodent model of lipopolysaccharide (LPS)-mediated acute lung injury, and a combination of primary human leukocytes and human ARDS serum. We also analyzed serum from non-lung disease intubated patients (controls) and sepsis-mediated ARDS patients. Compared to controls, ARDS demonstrates increased serum endotoxin and IL-6 levels, and decreased HDL, apoA-I and activity of anti-oxidant HDL-associated paraoxanase-1. L-4F inhibits the activation of isolated human leukocytes and neutrophils by ARDS serum and LPS in vitro. Further, L-4F decreased endotoxin activity and preserved anti-oxidant properties of HDL both in vitro and in vivo. In a rat model of severe endotoxemia, L-4F significantly decreased mortality and reduces lung and liver injury, even when administered 1 hour post LPS. Our study suggests the protective role of the apoA-I mimetic peptide L-4F in ARDS and gram-negative endotoxemia and warrant further clinical evaluation. The main protective mechanisms of L-4F are due to direct inhibition of endotoxin activity and preservation of HDL anti-oxidant activity.

Paraoxonases: ancient substrate hunters and their evolving role in ischemic heart disease

Interest in the role of paraoxonases (PON) in cardiovascular research has increased substantially over the past two decades. These multifaceted and pleiotropic enzymes are encoded by three highly conserved genes (PON1, PON2, and PON3) located on chromosome 7q21.3-22.1. Phylogenetic analysis suggests that PON2 is the ancient gene from which PON1 and PON3 arose via gene duplication. Although PON are primarily lactonases with overlapping, but distinct specificities, their physiologic substrates remain poorly characterized. The most interesting characteristic of PON, however, is their multifunctional roles in various biochemical pathways. These include protection against oxidative damage and lipid peroxidation, contribution to innate immunity, detoxification of reactive molecules, bioactivation of drugs, modulation of endoplasmic reticulum stress, and regulation of cell proliferation/apoptosis. In general, PON appear as "hunters" of old and new substrates often involved in athero- and thrombogenesis. Although reduced PON activity appears associated with increased cardiovascular risk, the correlation between PON genotype and ischemic heart disease remains controversial. In this review, we examine the biochemical pathways impacted by these unique enzymes and investigate the potential use of PON as diagnostic tools and their impact on development of future therapeutic strategies.

Quantitative assessment of the influence of paraoxonase 1 activity and coronary heart disease risk

Human paraoxonase 1 (PON1) is a calcium-dependent high-density lipoprotein associated ester hydrolase that has attracted considerable attention as a candidate factor for coronary heart disease (CHD) based on its function as a key factor in lipoprotein catabolism pathways. This meta-analysis aimed to clarify the inconsistency of published studies and to establish a comprehensive picture of the relationship between PON1 activity and CHD susceptibility. A systematic search was performed from PubMed, Web of Science, EMBASE, and CNKI databases. Ratio of means (RoM) between case and control and 95% confidence intervals (CIs) were calculated using a random-effects model. The source of heterogeneity was explored by subgroup analysis and meta-regression. We identified 47 eligible studies including a total of 9853 CHD cases and 11,408 controls. The pooled analysis showed that CHD patients had a 19% lower PON1 activity than did the controls (RoM=0.81; 95% CI: 0.74-0.89, p<10(-5)). In the subgroup analyses by CHD end points, a similar effect size was observed with coronary stenosis and myocardial infarction subgroups, with corresponding RoM of 0.81 (95% CI: 0.73-0.89, p<10(-4)) and 0.83 (95% CI: 0.74-0.93, p=0.001), respectively. Decreased PON1 activity associated with CHD risk was observed in almost all subgroup analysis according to ethnicity, sample size, study design, mean age of cases, source, and type of control. Decreased PON1 activity may act as a risk factor for the development of CHD. Progressive decrease in serum PON1 activity may exist for an individual with severe disease. However, larger studies using a prospective approach are needed to confirm our results.

Association between PON1 activity and coronary heart disease risk: a meta-analysis based on 43 studies

Paraoxonase 1 (PON1) is reported to have antioxidant and cardioprotective properties. The relationship between PON1 activity and coronary heart disease (CHD) risk in humans has been reported among various ethnic populations in the past decade. However, these studies have yielded contradictory results. To investigate this inconsistency, we conducted a meta-analysis of 43 studies involving a total of 20,629 subjects to evaluate the effect of PON1 activity on susceptibility for CHD. We also systematically explored potential sources of heterogeneity using subgroup analysis and meta-regression. Significant decreases paraoxonase activity of PON1 were observed in CHD patients compared with non-CHD controls with SMD of -0.78 (95% CI: -0.98, -0.57; P<0.001). Similar results were also found for arylesterase activity of PON1 with SMD of -0.50 (95% CI: -0.64, -0.36; P<0.001). In the subgroup analysis by ethnicity, CHD phenotype, sample size, source of controls, mean age and BMI of cases, significantly increased risks were also found. In addition, our analyses detected a possibility of publication bias with an overestimate of the true association by smaller studies. This meta-analysis demonstrated that decreasing in PON1 activity is a risk factor associated with increased CHD susceptibility. However, additional very large-scale studies are warranted to provide conclusive evidence on the effects of PON1 activity on risk of CHD.

Serum PON-1 activity but not Q192R polymorphism is related to the extent of atherosclerosis

AIM

Paraoxonase-1 (PON1) is an antioxidant enzyme located in high density lipoprotein (HDL). PON1 was defined as a protective factor against atherosclerosis. The aim of this study was to investigate the possible relationship between serum paraoxonase (PONase), homocysteine thiolactonase (HTase) activities and PON1 Q192R polymorphism, and the extent and severity of atherosclerosis.

METHODS

Blood specimens were collected from 142 individuals who had no coronary artery lesions angiographically (control group) and 128 individuals who had angiographically documented coronary artery disease of several degrees (patient group). The extent and severity of arterial lesions were evaluated by the Gensini scoring system. PONase and HTase activities were measured in serum using a spectrophotometric method. PON1 Q192R polymorphism was evaluated using PCR-RFLP after DNA isolation from blood.

RESULTS

Serum PONase and HTase activities were significantly lower in the patient group than in healthy controls (135.7±56.0U/mL vs 153.8±62.0U/mL, p< 0.05; 36.0±6.1 U/mL vs 43.0±4.04 U/mL, p< 0.01; respectively). In the patient group, there was a negative correlation between PONase, HTase activities and the Gensini score (r=-0.168, p= 0.039; r=-0.164, p= 0.006, respectively). In both groups, there was no significant difference in the distribution of PON1 Q192R polymorphism. In the patient group, the distribution of Gensini scores according to genotypes was not significant.

CONCLUSION

It has been concluded that serum PONase and HTase activities might be a more relevant marker than PON1 genotype in evaluating the extent and severity of atherosclerosis.

The anti-inflammatory effect of paraoxonase 1 against oxidized lipids depends on its association with high density lipoproteins

AIM

The aims of this study were to investigate whether purified PON1 can reduce the pro-inflammatory effect of oxidized phospholipids and whether the effect depended on its association with HDL.

MAIN METHODS

Lipid peroxidation was induced by copper ions and was measured using the conjugated diene method. Lysophosphatidylcholine (lyso-PC) formation was measured by HPLC with evaporative light scattering detection (ELSD) and ICAM-1 expression on Ea.hy926 endothelial cells was analyzed by flow cytometry.

KEY FINDINGS

Purified PON1 significantly inhibited copper-induced oxidation of LDL and HDL, causing a 60.5% and 77.7% decrease in conjugated diene formation, respectively. Incubating PON1 with oxLDL caused a significant increase in lyso-PC levels, while oxHDL caused a significant decrease. PON1 (12.5 to 50 μg/mL) had a pro-inflammatory effect in the presence of oxLDL, increasing ICAM-1 levels in Ea.hy926 cells by 33.0% and 40.6% (p<0.001) respectively, and had an anti-inflammatory effect in the presence of oxHDL, causing a 3-fold reduction in ICAM-1 levels. PON1 also caused a significant decrease in TNFα and purified lyso-PC-induced ICAM-1 expression. The results obtained with reconstituted HDL as well as LCAT and PAF-AH inhibitors suggested that the anti-inflammatory effect of PON1 against oxidized lipids is dependent on its association with HDL.

SIGNIFICANCE

Our results clearly showed that PON1 is involved in the anti-inflammatory effect of HDL and that the effect appears to depend on its association with HDL.

Four genetic polymorphisms of paraoxonase gene and risk of coronary heart disease: a meta-analysis based on 88 case-control studies

OBJECTIVE

The human paraoxonase (PON) is calcium dependent HDL associated ester hydrolase which has attracted considerable attention as a candidate gene for coronary heart disease based on its enzyme function as a key factor in lipoprotein catabolism pathways. Many studies have examined the association between polymorphisms in the PON gene and risk of coronary heart disease (CHD), but the results have been inconsistent.

METHODS

We conducted a meta-analysis of 88 studies on 4 PON polymorphisms [Q192R, L55M, and T(-107)C in the PON1 and the S311C in the PON2] published before August 2010, including a total of 24,702 CHD cases and 38,232 controls. We also systematically explored potential sources of heterogeneity.

RESULT

In a combined analysis, the summary per-allele odds ratio for CHD of the 192R was 1.11 (95% CI: 1.05-1.17). However, when the analyses were restricted to 10 larger studies (n>500 cases), the summary per-allele odds ratio was 0.96 (95% CI: 0.90-1.02). Our analyses detected a possibility of publication bias with an overestimate of the true association by smaller studies. A meta-analysis of studies on the 55M, (-107)T, and 311C variant showed no significant overall association with CHD, yielding a per-allele odds ratio of 0.94 (95% CI: 0.88-1.00), 1.02 (95% CI: 0.91-1.15) and 1.02 (95% CI: 0.90-1.16) respectively.

CONCLUSIONS

This meta-analysis suggested an overall weak association between the R192 polymorphism and CHD risk.

The three-gene paraoxonase family: physiologic roles, actions and regulation

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. By far the most-studied member is PON1, a high-density lipoprotein-associated esterase/lactonase, also endowed with the capacity to hydrolyze organophosphates, but all the three proteins prevent oxidative stress and fight inflammation. They therefore seem central to a wide variety of human illnesses, including atherosclerosis, diabetes mellitus, mental disorders and inflammatory bowel disease. The major goal of this review is to highlight the regulation of each of the paraoxonase components by diverse nutritional molecules and pharmacological agents as well as a number of pathophysiological events, such as oxidative stress and inflammation. Considerable and detailed cell-based studies and animal model experiments have been provided to allow a thorough scrutiny of PON modulation, which will increase our understanding and ability to target these genes in order to efficiently increase their transcriptional activity and decrease the risks of developing different disorders.