Crosstalk Between Adipokines and Paraoxonase 1: A New Potential Axis Linking Oxidative Stress and Inflammation

Diacerein mitigates endocrine and cardio-metabolic disruptions in experimental PCOS mice model by modulating AdipoR1/ PON 1

BACKGROUND

This study aimed to explore the impact of Diacerein (DIC) on endocrine and cardio-metabolic changes in polycystic ovarian syndrome (PCOS) mouse model.

METHODS

A total of 18 adult female mice (Parkes strain), aged 4-5 weeks, were randomly assigned to three groups, each comprising 6 animals, as follows: Group I (control), received normal diet and normal saline as vehicle for 51 days; Group II received Letrozole (LET; 6 mg/kg bw) for 21 days to induce PCOS; Group III received LET, followed by daily oral gavage administration of DIC (35 mg/kg bw) for 30 days.

RESULTS

This study indicates that treatment with LET resulted in PCOS with characteristics such as polycystic ovaries, elevated testosterone, weight gain, visceral adiposity, high levels of insulin as well as fasting blood glucose in addition to insulin resistance, improper handling of ovarian lipids, atherogenic dyslipidemia, impaired Na + /K + -ATPase activity and serum, cardiac, and ovarian oxidative stress. Serum/ovarian adiponectin levels were lowered in LET-treated mice. In mice treated with LET, we also discovered a reduction in cardiac and serum paraoxonase 1 (PON1). Interestingly, DIC restored ovarian andcardio-metabolic abnormalities in LET-induced PCOS mice. DIC prevented the endocrine and cardio-metabolic changes brought on by letrozole-induced PCOS in mice.

CONCLUSION

The ameliorative effects of DIC on letrozole-induced PCOS with concurrent oxidative stress, abdominal fat deposition, cardiac and ovarian substrate mishandling, glucometabolic dysfunction, and adiponectin/PON1 activation support the idea that DIC perhaps, restore compromised endocrine and cardio-metabolic regulators in PCOS.

Differential absorption of cadmium and zinc by tobacco plants: Role of apoplastic pathway

Cadmium (Cd) contamination presents a significant challenge in global agriculture. This study explores the efficacy of chemical induction, specifically using sodium chloride (NaCl), to limit Cd uptake in tobacco (Nicotiana tabacum) and assesses its impact on essential divalent metal ions (DMIs). We conducted a comprehensive analysis encompassing ion absorption, root histology, and biochemistry to understand the influence of this method. Our results revealed that NaCl induction led to a notable 30 % decrease in Cd absorption, while maintaining minimal impact on zinc (Zn) uptake. Intriguingly, the absence of essential DMIs, such as calcium (Ca), magnesium (Mg), and Zn, was found to diminish the plant's capacity to absorb Cd. Furthermore, moderate NaCl induction resulted in an increased diameter of the root stele and enhanced lignin content, indicating a restriction of Cd absorption through the apoplastic pathway. Conversely, a compensatory absorption mechanism via the symplastic pathway appeared to be activated in the absence of essential elements. These findings highlight the potential of chemical induction as a strategy to mitigate agricultural Cd risks, offering insights into the complex interplay between plant ion transport pathways and metal uptake regulation.

Signature of paraoxonases in the altered redox homeostasis in Alzheimer's disease

Paraoxonase (PON) enzymes (PON1, PON2 and PON3) exert antioxidant properties through arylesterase, lactonase and paraoxonase activities. Increasing findings suggested their potential involvement, particularly PON1 and PON2, in Alzheimer's disease (AD), a neurodegenerative pathology characterized by early oxidative stress. Specifically, decreased serum PON1-arylesterase and lactonase activities seem to be associated with an increased brain oxidative damage in early AD, leading to hypothesize that PON activity alterations might be an early event in AD. To address this hypothesis, the levels of 4-hydroxynonenal (4-HNE; i.e. a marker of oxidative stress damage) along with the protein expression and enzymatic activity of PON1 and PON2 have been investigated in the brain and serum of young [Postnatal day (PD)8-10, 20-25 and 60-65] asymptomatic 3xTg-AD female mice, one of the most used transgenic models of AD. At PD 8-10, there were no differences in hippocampus and prefrontal cortex (PFC) 4-HNE expression levels between 3xTg-AD mice compared to controls (Non-Tg mice). On the other hand, significant increased levels of 4-HNE were detected in PD 20-30 3xTg-AD mice hippocampus, while a significant reduction was observed in 3xTg-AD group at PD 60-65. In the PFC, 4-HNE levels were significantly reduced in 3xTg-AD mice brain at PD 20-30, while no differences in 4-HNE levels were detected at PD 60-65. No significant differences in arylesterase and lactonase activities were observed in the plasma of 3xTg-AD and Non-Tg mice at the different considered ages. Compared to Non-Tg mice, a reduction of brain arylesterase activity was found in 3xTg-AD female at PD 20-30 and PD 60-65, but it was significant only in the younger group. Finally, a similar trend was observed also for PON1 and PON2 protein levels, with both significantly, and solely, decreased in 3xTg-AD mice brain at PD 20-30. Overall, these findings suggest that the altered oxidative stress homeostasis in the 3xTg-AD female mice may be related to an early reduction in activity and expression of PONs enzymes most likely via a reduced brain arylesterases activity.

The Association of Adipokines and Myokines in the Blood of Obese Children and Adolescents with Lipoprotein Lipase rs328 Gene Variants

Obesity develops largely due to genetic factors, with the genetic polymorphism of lipid metabolism enzymes being of particular importance. However, it is still unclear how the genetic variants of one of the key enzymes in lipid transport, lipoprotein lipase (LPL), are associated with the endocrine function of mesenchymal tissues in obesity. The current study was aimed at the investigation of the LPL rs328 gene variant association with adipokines and myokines levels, as well as lipid metabolism indices in the blood of children and adolescents of both genders with obesity. We found that LPL polymorphism rs328 is not characterized by the differences in the levels of hormones, adipokines, and myokines and in the blood of healthy children and adolescents; however, it significantly affects these indices during obesity in gender-dependent manner. The shifts in hormones, adipokines, and myokines manifest mostly in the obese individuals with Ser447Ser genotype rather than with 447Ter genotype. Obese boys homozygous for Ser447Ser have more elevated leptin levels than girls. They also demonstrate lower adiponectin, apelin, prolactin, and osteocrine levels than those in obese girls with the same genotype. The gender-based differences are less pronounced in individuals with 447Ter genotype than in the homozygotes for 447Ser. Thus, we conclude that the polymorphism rs328 of the lipoprotein lipase gene is accompanied by the changes in hormones, adipokines, and myokines levels in the blood of children and adolescents with obesity in gender-dependent manner.

Paraoxonase 1 status is a major Janus-faced component of mild and moderate acute ischemic stroke and consequent disabilities

AIMS

This study aims to examine the associations between paraoxonase 1 (PON)1 status and acute ischemic stroke (AIS) and consequent disabilities.

METHODS

This study recruited 122 patients with AIS and 40 healthy controls and assessed the Q192R gene variants, arylesterase (AREase) and chloromethyl phenylacetate (CMPAase) activities, and high-density lipoprotein cholesterol (HDLc) in baseline conditions. AREase and CMPAase were measured 3 months later. The National Institutes of Health Stroke Scale (NIHSS) and the modified Rankin score (mRS) were assessed at baseline and 3 and 6 months later.

RESULTS

Reduced CMPAase and increased AREase activities are significantly associated with AIS and mRS and NIHSS scores (baseline and 3 and 6 months later). The best predictor of AIS/disabilities was a decrease in the z-unit-based composite zCMPAase-zAREase score. Serum high density lipoprotein cholsterol (HDLc) was significantly correlated with CMPAase, but not AREase, activity and a lowered zCMPAase + zHDLc score was the second best predictor of AIS/disabilities. Regression analysis showed that 34.7% of the variance in baseline NIHSS was explained by zCMPAase-zAREase and zCMPAase + zHDLc composites, HDLc, and hypertension. Neural network analysis showed that stroke was differentiated from controls with an area under the ROC curve of 0.975 using both new composite scores, PON1 status, hypertension, dyslipidemia, previous stroke as body mass index. The PON1 Q192R genotype has many significant direct and mediated effects on AIS/disabilities, however, its overall effect was not significant.

DISCUSSION

PON1 status and the CMPAase-HDLc complex play key roles in AIS and its disabilities at baseline and 3 and 6 months later.

Antioxidative Effects of Black Currant and Cornelian Cherry Juices in Different Tissues of an Experimental Model of Metabolic Syndrome in Rats

A Western-style diet, rich in fat and simple sugars, is the main risk factor for a significant number of chronic diseases and disorders, as well as for a progression of metabolic syndrome (MetS). One of the key mechanisms involved in MetS development is increased oxidative stress caused by the accumulation of body fat. Some dietary polyphenols have shown a protective role in preventing oxidative-stress-induced damage. We investigated the difference in the oxidative response of plasma, liver, and visceral adipose tissue in rats fed with a high-fat high-fructose (HFF) diet for ten weeks, and the effectiveness of polyphenol-rich juices (black currant (BC) and cornelian cherry (CC)) in HFF-diet-induced oxidative stress prevention. The most prominent impact of the HFF diet on redox parameters was recorded in the liver, whereas adipose tissue showed the most potent protection mechanisms against oxidative stress. Consumption of both juices decreased advanced oxidation protein product (AOPP) level in plasma, increased paraoxonase1 (PON1) activity in the liver, and significantly decreased total oxidative status (TOS) in adipose tissue. BC exerted stronger antioxidative potential than CC and decreased the superoxide anion radical (O₂^•-) level in the liver. It also reduced TOS, total antioxidative status (TAS), and malondialdehyde (MDA) concentration in adipose tissue. The multiple linear regression analysis has shown that the best predictors of MetS development, estimated through the increase in visceral adiposity, were superoxide dismutase (SOD), AOPP, TOS, and TAS. The consumption of polyphenol-rich juices may provide a convenient approach for the systemic reduction of oxidative stress parameters.

Resistin Contribution to Cardiovascular Risk in Chronic Kidney Disease Male Patients

BACKGROUND

Resistin is a molecule that belongs to the Resistin-Like Molecules family (RELMs), the group of proteins taking part in inflammatory processes. Increased resistin concentrations are observed in cardiovascular complications. Resistin contributes to the onset of atherosclerosis and intensifies the atherosclerotic processes. The aim of this study was to investigate the relationship between resistin and cardiovascular (CV) risk in men with chronic kidney disease (CKD) not treated with dialysis.

MATERIALS AND METHODS

One hundred and forty-two men were included in the study: 99 men with eGFR lower than 60 mL/min/1.73 m² and 43 men with eGFR ≥ 60 mL/min/1.73 m². CV risk was assessed. Serum resistin, tumor necrosis factor-alpha (TNF-alpha) and plasminogen activator inhibitor-1 (PAI-1) were measured among other biochemical parameters.

RESULTS

We observed that resistin concentrations were significantly higher in patients with CKD compared to individuals with eGFR ≥ 60 mL/min/1.73 m² (p = 0.003). In CKD, after estimating the general linear model (GLM), we found that resistin is associated with CV risk (p = 0.026) and PAI-1 serum concentrations (0.012). The relationship of PAI-1 with resistin depends on the level of CV risk in CKD (p = 0.048).

CONCLUSIONS

Resistin concentrations rise with the increase of CV risk in CKD patients and thus resistin may contribute to the progression of cardiovascular risk in this group of patients. The relationship between resistin and CV risk is modified by PAI-1 concentrations.

Investigation of Paraoxonase-1 Genotype and Enzyme-Kinetic Parameters in the Context of Cognitive Impairment in Parkinson's Disease

Cognitive impairment is a common non-motor symptom of Parkinson's disease (PD), which often progresses to PD dementia. PD patients with and without dementia may differ in certain biochemical parameters, which could thus be used as biomarkers for PD dementia. The enzyme paraoxonase 1 (PON1) has previously been investigated as a potential biomarker in the context of other types of dementia. In a cohort of PD patients, we compared a group of 89 patients with cognitive impairment with a group of 118 patients with normal cognition. We determined the kinetic parameters K_m and V_max for PON1 for the reaction with dihydrocoumarin and the genotype of four single nucleotide polymorphisms in PON1. We found that no genotype or kinetic parameter correlated significantly with cognitive impairment in PD patients. However, we observed associations between PON1 rs662 and PON1 K_m (p < 10^-10), between PON1 rs662 and PON1 V_max (p = 9.33 × 10^-7), and between PON1 rs705379 and PON1 V_max (p = 2.21 × 10^-10). The present study is novel in three main aspects. (1) It is the first study to investigate associations between the PON1 genotype and enzyme kinetics in a large number of subjects. (2) It is the first study to report kinetic parameters of PON1 in a large number of subjects and to use time-concentration progress curves instead of initial velocities to determine K_m and V_max in a clinical context. (3) It is also the first study to calculate enzyme-kinetic parameters in a clinical context with a new algorithm for data point removal from progress curves, dubbed iFIT. Although our results suggest that in the context of PD, there is no clinically useful correlation between cognitive status on the one hand and PON1 genetic and enzyme-kinetic parameters on the other hand, this should not discourage future investigation into PON1's potential associations with other types of dementia.

Importance of Polymorphisms in the Gene of Paraoxonase-1 (SNP rs662) and Apolipoprotein A-I (SNP rs670 and rs5069) in Non-Smoking and Smoking Healthy Subjects and Patients with Acute Pancreatitis

Oxidative stress has been implicated in the initiation of acute pancreatitis (AP). HDL is considered to be a preventing factor against cell membrane oxidation, thanks to the presence on its surface of apolipoprotein A-I (apoA-I) and paraoxonase-1 (PON1), which activity can be modified by genetic and environmental factors. The impact of SNP rs662 in the PON1 gene and SNP rs670 and rs5069 in the APOAI gene on PON1 activities and its concentration in the population of AP patients and healthy volunteers was investigated. In the group of patients with AP, a decreased HDL concentration and PON1 activities were observed. A decrease in the aryloesterase and lactonase activities of PON1 in AP patients with the TT genotype for SNP rs662 (especially in smokers) was found. In the group of patients with the AA genotype (rs670), the highest concentrations of HDL and apoA-I were observed, which were gradually decreasing in the course of AP. Changes in the concentration of apoA-I were associated with the changes in the concentration and activities of PON1 in the AP patients with the AA genotype for SNP rs670. A decreasing apoA-I concentration contributing to lowering PON1 concentration and its activities during the hospitalization of AP patients with the CC genotype for SNP rs5069 were shown. Therefore, more susceptibility of persons with the CC genotype for SNP rs5069 to pro/antioxidative imbalance was shown. In this process, an important role was played by the HDL level and its interaction with PON1 and apoA-I.

Association between the visceral adiposity index and risks of all-cause and cause-specific mortalities in a large cohort: Findings from the UK biobank

BACKGROUND AND AIMS

The visceral adiposity index (VAI) has been recently established as a measure of visceral fat distribution and is shown to be associated with a wide range of adverse health events. However, the precise associations between the VAI score and all-cause and cause-specific mortalities in the general population remain undetermined.

METHODS AND RESULTS

In this large-scale prospective epidemiological study, 357,457 participants (aged 38-73 years) were selected from the UK Biobank. We used Cox competing risk regression models to estimate the association between the VAI score and all-cause, cardiovascular disease (CVD), cancer, and other mortalities. The VAI score was significantly correlated with an increased risk of all-cause mortality (hazard ratio [HR], 1.200; 95% confidence interval [CI], 1.148-1.255; P < 0.0001), cancer mortality (HR, 1.224; 95% CI, 1.150-1.303; P < 0.0001), CVD mortality (HR, 1.459; 95% CI, 1.148-1.255; P < 0.0001), and other mortalities (HR, 1.200; 95% CI, 1.148-1.255; P < 0.0001) after adjusting for a series of confounders. In addition, the subgroup analyses showed that HRs were significantly higher in participants who were male, aged below 65 years, and body mass index less than 25.

CONCLUSION

In summary, VAI was positively associated with an increased risk of all-cause and cause-specific mortalities in a nationwide, well-characterised population identified in a UK Biobank. The VAI score might be a complementary traditional predictive indicator for evaluating the risk of adverse health events in the population of Western adults aged 38 years and older.

IL-6 and Leptin Are Potential Biomarkers for Osteoporotic Fracture Risk Assessment and Prediction of Postmenopausal Women with Low Bone Mass: A Follow-Up Study Using a Regional Sample Cohort

Osteoporotic fracture, a major complication which is known as the outcome postmenopausal osteoporosis, seriously threatens the health of postmenopausal women. At present, the traditional osteoporotic fracture prediction methods are characterized by inconvenient application and time-consuming statistical results, while predictive serum biomarkers can make up for this shortcoming. Accurate and advanced risk prediction of osteoporotic fracture is meaningful to early prevention and intervention, effectively avoiding the risk of this disease and the secondary fracture in the surgical treatment. In this study, based on the BEYOND cohort, a 2-year follow-up study was conducted after subjects participated to survey if OF occurred. Independent sample t-test and Mann–Whitney U-test were used to analyze the differences of bone metabolism biomarkers between the OF and non-OF group. Cox proportional hazard model was used to screen the potential biomarkers might be used to predict OF risk. ROC curves and AUCs were used to analyze the predictive accuracy, and the Delong's test was used to compare the differences between the AUCs. 15 postmenopausal women with low bone mass and OF were found, and other 60 subjects without OF were matched with 1 : 4, age, and BMI classification as control group. The serum IL-6 (OR = 1.139, 95%CI = 1.058 − 1.226) and leptin (OR = 0.921, 95%CI = 0.848 − 1.000) were found as OF risk predictive biomarkers for postmenopausal women with low bone mass with high accuracy (IL − 6 = 0.871) (leptin = 0.813) and accuracy enhanced when they were combined (AUC = 0.898). The results of Delong's test showed that the difference of AUC between leptin and IL-6&Leptin was meaningful (P = 0.024) but meaningless between IL-6 and leptin (P = 0.436), IL-6 and IL-6&Leptin (P = 0.606). To sum up, IL-6 and leptin are the predictive biomarkers of OF for postmenopausal women with low bone mass. The IL-6 can improve the prediction accuracy of leptin (P = 0.024), but not vice versa (P = 0.606). Trial Information. Registered on the Chinese Clinical Trial Registry already. (Registration Number: ChiCTR-SOC-17013090).

Association between inflammatory markers and serum paraoxonase and arylesterase activities in the general population: a cross-sectional study

Background

Recent studies focused on modulating factors of paraoxonase-1 (PON1) activity. In some studies the association between pro-inflammatory markers and PON1 activity was examined, but so far no population-based investigations on this issue have been conducted. The present study investigated the relationships between the pro-inflammatory markers tumor necrosis factor (TNF)-α, leptin, interleukin (IL)-6, and high-sensitive C-reactive protein (hs-CRP) and paraoxonase and arylesterase, two hydrolytic activities of PON1, in the population-based Bavarian Food Consumption Survey II.

Methods

Based on 504 participants (217 men, 287 women), the relationship between the pro-inflammatory markers and the outcomes paraoxonase and arylesterase activities were investigated using multivariable linear models.

Results

Circulating plasma levels of leptin (P-value < 0.0001), hs-CRP (P-value = 0.031) and IL-6 (P-value = 0.045) were significantly non-linearly associated with arylesterase activity. Leptin levels were also significantly associated with paraoxonase activity (P-value = 0.024) independently from confounding factors, including high-density lipoprotein (HDL) cholesterol. With increasing levels of these inflammatory parameters, arylesterase and paraoxonase activities increased; however, at higher levels (> 75th percentile) the activities reached a plateau or even decreased somewhat. After Bonferroni-Holm correction, only leptin remained non-linearly but significantly associated with arylesterase activity (adjusted overall P-value < 0.0001). Neither age nor sex nor obesity modified the associations. No association was found between TNF-α and paraoxonase or arylesterase activity.

Conclusions

The present findings suggest that in persons with very high levels of inflammation, PON1 activity may be impaired, a fact that might subsequently be accompanied by a higher risk for cardiometabolic diseases. Whether or not the measurement of PON1 activity in combination with a lipid profile and certain inflammatory markers could improve the prediction of cardiometabolic diseases in middle-aged individuals from the general population should be evaluated in clinical studies.

Moderate Caloric Restriction Partially Improved Oxidative Stress Markers in Obese Humans

Oxidative stress and inflammation are implicated in obesity. Therefore, we investigated whether moderate and short-term calorie restriction (CR) reflects a real-life situation, mediates weight loss, and improves oxidative stress markers. We analyzed oxidative stress markers in patients with obesity undergoing moderate CR. Serum oxidative stress markers (myeloperoxidase (MPO), superoxide dismutase (SOD), catalase, total antioxidant status (TAS), and reactive oxygen species (ROS) (generation by endothelial cells in vitro)) were measured in 53 subjects (mean BMI 37.8 ± 5.9 kg/m²) who underwent 8 weeks of CR, which included a reduction of 300-500 kcal/day. MPO was the most CR-sensitive parameter. The mean level of serum MPO in patients with obesity was 20% higher than that in post CR intervention (p < 0.001). SOD increased by 12% after CR (p < 0.05), which was largely due to the improvement in glucose tolerance and the reduction in insulin resistance after CR. Other tested parameters were not modified during the treatment. CR resulted in an expected decrease in body weight (by 5.9 ± 4.6 kg, p < 0.0001) and other anthropometric parameters. Additionally, it was accompanied by a significant change in hsCRP, hsTNF alpha, hsIL-6, leptin (all p < 0.0001), and HOMA-IR (p < 0.05). Cardiovascular and metabolic parameters were also partially improved. Short-term, moderate CR partially improves antioxidant capacity but is enough to substantially change anthropometric parameters in obese patients. Our observations indicate that mimicking real-life situations and low-cost dietary intervention can be successfully implemented in obesity treatment with a simultaneous moderate effect on antioxidant status.

Cytokines, paraoxonase-1, periostin and non-invasive liver fibrosis scores in patients with non-alcoholic fatty liver disease and persistently elevated aminotransferases: A pilot study

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. The aim of this study was to evaluate the possible association between paraoxonase-1 (PON1), periostin (POSTN), tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10 serum concentration with non-invasive liver fibrosis scores, in a cohort of patients with NAFLD. We studied a cohort of 52 patients diagnosed with NAFLD. The NAFLD fibrosis score (NFS), Fibrosis-4 Index (FIB-4), AST to platelet ratio index (APRI) and BARD scores were calculated for each patient. We determined the PON1, POSTN, TNF-α, IL-6, and IL-10 serum values using ELISA kits. There was no correlation between PON1 or POSTN serum levels and non-invasive liver fibrosis. The TNF-α serum values were independently associated with the liver fibrosis scores (P=0.02 for NFS and P=0.002 for FIB-4). Age and metabolic syndrome were also independently linked to the fibrosis scores. In conclusion, serum levels of TNF-α, age and metabolic syndrome were associated with the non-invasive liver fibrosis scores.

Improving the prognosis of renal patients: The effects of blood flow-restricted resistance training on redox balance and cardiac autonomic function

NEW FINDINGS

What is the central question of this study? Can resistance training with and without blood flow restriction improve redox balance and positively impact the autonomic cardiac modulation in chronic kidney disease patients? What is the main finding and its importance? Resistance training with and without blood flow restriction improved antioxidant defence (paraoxonase 1), decreased the pro-oxidative myeloperoxidase, improved cardiac autonomic function and slowed the decrease in renal function. We draw attention to the important clinical implications for the management of redox balance and autonomic cardiac function in chronic kidney disease patients.

ABSTRACT

Patients with chronic kidney disease (CKD) are prone to cardiovascular diseases secondary to abnormalities in both autonomic cardiac function and redox balance [myeloperoxidase (MPO) to paraoxonase 1 (PON1) ratio]. Although aerobic training improves both autonomic balance and redox balance in patients with CKD, the cardioprotective effects of resistance training (RT), with and without blood flow restriction (BFR), remain unknown. We aimed to compare the effects of RT and RT+BFR on antioxidant defence (PON1), pro-oxidative status (MPO), cardiac autonomic function (quantified by heart rate variability analysis) and renal function. Conservative CKD (stages 1 to 5 who do not need hemodialysis) patients (n = 105, 33 female) of both sexes were randomized into three groups: control (CTL; 57.6 ± 5.2 years; body mass index, 33.23 ± 1.62 kg/m² ), RT (58.09 ± 6.26 years; body mass index 33.63 ± 2.05 kg/m² ) and RT+BFR (58.06 ± 6.47 years; body mass index, 33.32 ± 1.87 kg/m² ). Patients completed 6 months of RT or RT+BFR on three non-consecutive days per week under the supervision of strength and conditioning professionals. Training loads were adjusted every 2 months. Heart rate variability was recorded with a Polar-RS800 and data were analysed for time and frequency domains using Kubios software. The redox balance markers were PON1 and MPO, which were analysed in plasma samples. Renal function was estimated as estimated glomerular filtration rate. The RT and RT+BFR decreased pro-oxidative MPO (RT, ∼34 ng/ml and RT+BFR, ∼27 ng/ml), improved both antioxidant defence (PON1: RT, ∼23 U/L and RT+BFR, ∼31 U/L) and cardiac autonomic function (R-R interval: RT, ∼120.4 ms and RT+BFR, ∼117.7 ms), and slowed the deterioration of renal function (P < 0.0001). Redox balance markers were inversely correlated with heart rate variability time-domain indices. Our data indicated that both training models were effective as non-pharmacological tools to increase the antioxidant defences, decrease oxidative stress and improve the cardiac autonomic function of CKD patients.

Sex Difference Impacts on the Relationship between Paraoxonase-1 (PON1) and Type 2 Diabetes

Type-2 diabetes (T2D) and its cardiovascular complications are related to sex. Increasing evidence suggests that paraoxonase 1 (PON1) activity, an antioxidant enzyme bound to high-density lipoproteins (HDL), is implicated in the onset and clinical progression of T2D. Since we previously showed that PON1 is a sexual dimorphic protein, we now investigated whether sex might impact the relationship between PON1 and this chronic disease. To address this aim, we assessed PON1 activity in the sera of 778 patients, including controls (women, n = 383; men, n = 198) and diabetics (women, n = 79; men = 118). PON1 activity decreased in both women and men with T2D compared with controls (p < 0.05 and p > 0.001, respectively), but the change was 50% larger in the female cohort. In line with this result, the enzyme activity was associated with serum glucose level only in women (r = -0.160, p = 0.002). Notably, only within this gender category, lower PON1 activity was independently associated with increased odds of being diabetic (odds ratio (95% Confidence interval: 2.162 (1.075-5.678)). In conclusion, our study suggests that PON1-deficiency in T2D is a gender-specific phenomenon, with women being more affected than men. This could contribute to the partial loss of female cardiovascular advantage associated with T2D.

Identification of Protein Expression Changes in Hepatocellular Carcinoma through iTRAQ

Background

Hepatocellular carcinoma (HCC) is a malignant tumor associated with a poor prognosis. Serum biomarkers of HCC have the potential to improve the diagnosis, provide a means to monitor the tumors, and predict their malignancy. Proteins that are expressed differentially between HCC patients and normal controls have the potential to be biomarkers.

Method

Serum samples from 10 confirmed HCC patients and 10 controls were collected. The differentially expressed proteins in the serum were identified using an isobaric tags for relative and absolute quantitation- (iTRAQ-) based method. Potential serum biomarkers were validated by ELISA in another 20 HCC patients and 20 controls. Their expression data in HCC were extracted from The Cancer Genome Atlas (TCGA) dataset.

Results

A total of 260 proteins were measured in the serum of HCC patients and compared to those in sex- and age-matched normal controls. Forty-one proteins displayed significant changes, with 26 being downregulated and 15 being upregulated. Upregulated proteins included alpha-1-antitrypsin (A1AT) and peroxiredoxin 2 (PRDX2), and downregulated proteins included paraoxonase 1 (PON1) and C-reactive protein (CRP). We then used ELISA to measure serum levels of A1AT, PRDX2, PON1, and CRP in another 20 patients with HCC and found that only PON1 levels were consistent with the iTRAQ result. In TCGA dataset, PON1 expression was downregulated in HCC tissues (P < 0.001) and low expression of PON1 was associated with poor survival in HCC patients (P < 0.001) and low expression of PON1 was associated with poor survival in HCC patients (

Conclusions

PON1 could act as a biomarker for HCC to assist in the diagnosis of HCC.