Serum Paraoxonase Activity Research Articles

Relationship of paraoxonase-1 and paraoxonase-3 with routine laboratory tests and oxidative stress in type 2 diabetes mellitus

Abstract Objectives We aimed to investigate the relationship between serum paraoxonase-1 (PON1) and paraoxonase-3 (PON3) levels and activities with hemoglobin A1c (HbA1c), serum fasting blood glucose, lipid profile, and oxidative stress in patients with type 2 diabetes mellitus (T2DM). Also, we aimed to examine PON1 and PON3 levels and activities in these patients according to the HbA1c goal in diabetes treatment and PON1192 phenotypes. Methods One hundred forty-one volunteers diagnosed with T2DM participated in this study. Serum PON1 and PON3 levels and activities, total oxidant status (TOS), and total antioxidant status (TAS) were measured. PON1192 phenotypes were determined by using PON1 activities. Also, HbA1c, serum fasting blood glucose, and lipid profile results, which were measured for routine examination on the same day as sample collection, were used for this study. Results There was a positive relationship between arylesterase and lactonase activities and high-density lipoprotein cholesterol (HDL-C), between lactonase activity and TAS, and a negative relationship between PON1 level and TAS in patients with T2DM. Our study also showed that PON3/HDL-C was higher in patients with HbA1c levels ≥7 %. Lactonase activities were higher in patients with PON1Q192Q and PON1Q192R phenotypes than in patients with PON1R192R phenotypes. Conclusions PON1 and PON3 levels and activities alone could not be associated with immediate or long-term blood glucose levels in patients with T2DM. Higher PON3/HDL-C in patients with HbA1c levels ≥7 % may show a protective role of PON3 in defense against higher glucose levels. Also, we found that the PON1192 phenotype can affect serum lactonase activity.

Serum Paraoxonase Activity and Phenotype Distribution in Covid-19 Patients

Objective: For the phenotype classification, it is important to determine the relationship between enzyme activity and the severity of the COVID-19 disease. Reaching significant differences between healthy and infected individuals in terms of genotype and allele distributions may be a guide in the fight against the COVID-19 pandemic. This study, it was aimed to investigate the relationship between serum arylesterase PON1 enzyme activity and disease severity in COVID-19 patients. Methods: Patients over the age of 18 who applied to the Emergency Service between 01-30 April 2020 and were examined with a preliminary diagnosis of COVID-19 were included in the study. In the study, serum PON1 activity was measured in the venous blood of 56 patients diagnosed with Covid-19 disease by either CT or RT-PCR and who have not received any systemic treatment yet. Results: The Arylesterase (AREase) and Paraoxonase (POase) activity levels of the study and control groups were 131.49 ± 52.75 kU/L 142.29 ± 38.82 kU/L, 276.48 ± 220.4 U/L 505.30 ± 301.4 U/L, respectively. It was found that 64.3 % of those infected with Covid-19 had the low-activity PON1 phenotype (p= 0.007) Conclusion: Genetic variability in PON1 may be associated with exposure to or risk of developing the disease. As a result, vaccination of individuals with low activity phenotype can be given priority at the vaccination stage in order to reduce the mortality rate in the fight against the pandemic. Awareness and protection measures of societies with low activity phenotypes can be increased.

The use of serum paraoxonase-1 to assess inflammation in horses with colitis.

Paraoxonase-1 (PON-1) has been suggested as a marker of inflammation and oxidative stress in horses and could potentially be used for prognostication in horses with colitis. Assessment of PON-1 in horses with colitis and comparison of two methods. Serum PON-1 was measured by two methods (paraoxon and p-nitrophenyl acetate) in 161 horses with colitis and 57 controls. Follow-up samples obtained during hospitalization were available from 106 horses with colitis. The two methods were compared. Serum PON-1 was significantly lower in horses with colitis than in healthy horses (P < .0001 for both methods) as well as in nonsurvivors compared with survivors (P = .0141 [paraoxon-based method] and P < .0001 [p-nitrophenyl acetate-based method]), but with marked overlap between groups. PON-1 activity did not change parallel to a change in inflammatory status in response to treatment when assessed at admission and in up to seven follow-up samples. Admission PON-1 activity could not reliably classify horses as survivors or nonsurvivors, with sensitivity and specificity ranging between 53.1% and 72.9%. Results from the two methods were comparable. Both methods reliably measured serum PON-1 activity. Significant differences in PON-1 activity were found between healthy horses and horses with colitis and between survivors and nonsurvivors. However, PON-1 activity varied considerably within groups. Both the proposed reference intervals as well as alternative cutoff values resulted in suboptimal diagnostic and prognostic performance, and the use of serum PON-1 in horses with colitis thus seems to add little to existing diagnostic and prognostic markers.

Paraoxonase 1: evolution of the enzyme and of its role in protecting against atherosclerosis.

To review the discoveries which led to the concept that serum paraoxonase 1 (PON1) is inversely related to atherosclerotic cardiovascular disease (ASCVD) incidence, how this association came to be regarded as causal and how such a role might have evolved. Animal models suggest a causal link between PON1 present on HDL and atherosclerosis. Serum PON1 activity predicts ASCVD with a similar reliability to HDL cholesterol, but at the extremes of high and low HDL cholesterol, there is discordance with PON1 being potentially more accurate. The paraoxonase gene family has its origins in the earliest life forms. Its greatest hydrolytic activity is towards lactones and organophosphates, both of which can be generated in the natural environment. It is active towards a wide range of substrates and thus its conservation may have resulted from improved survival of species facing a variety of evolutionary challenges. Protection against ASCVD is likely to be the consequence of some promiscuous activity of PON1, but nonetheless has the potential for exploitation to improve risk prediction and prevention of ASCVD.

A Comparative Analysis of the Serum Paraoxonase (PON1) Activity and the Concentration of Parameters of Lipid Profile after 3 Months of Statin Therapy

Background: Human serum paraoxonase (PON1) residing on HDL can prevent the oxidation of low densitylipoprotein (LDL), the initiating factor in atherosclerosis. Statins are commonly used to treat dyslipidemia,aknown risk factor for coronary artery disease (CAD).The aim of the studyis to evaluate the alterations in theconcentrationof PON1 along with that of other parameters of lipid profile in patients of CAD before and after 3 months of statin therapy.Materials and Methods: The study included 30 new patients who were put on statin therapy following thediagnosis of acute coronary syndrome. The activity of PON1 (units-IU/L) and the concentration of lipid profileparameters (units-mg/dl) were estimated before starting statin therapy and again after three months. Patients with co-morbidities like diabetes, kidney disease, liver disease and other cardiac diseases of infectious aetiology were excluded.Results and Analysis: As expected, both PON1 and HDL have increased after 3 months. There was a statistically significant increase in both PON1 (p&lt;0.05)and HDL (p&lt;0.001) and a decrease (p &lt;0.05, also statistically significant)in LDL after 3 months of statin therapy.Conclusion: This knowledge may be exploited in the follow up CAD patients. The increase in PONI and thesimilar increase in HDL after 3 months of statin therapy may be exploited in the follow-up of cardiac patients.

Corinthian Currants Promote the Expression of Paraoxonase-1 and Enhance the Antioxidant Status in Serum and Brain of 5xFAD Mouse Model of Alzheimer's Disease.

Paraoxonase-1 (PON1), a serum antioxidant enzyme, has been implicated in Alzheimer's disease (AD) pathogenesis that involves early oxidative damage. Corinthian currants and their components have been shown to display antioxidant and other neuroprotective effects in AD. We evaluated the effect of a Corinthian currant paste-supplemented diet (CurD), provided to 1-month-old 5xFAD mice for 1, 3, and 6 months, on PON1 activity and levels of oxidation markers in serum and the brain of mice as compared to a control diet (ConD) or glucose/fructose-matched diet (GFD). Administration of CurD for 1 month increased PON1 activity and decreased oxidized lipid levels in serum compared to ConD and GFD. Longer-term administration of CurD did not, however, affect serum PON1 activity and oxidized lipid levels. Furthermore, CurD administered for 1 and 3 months, but not for 6 months, increased PON1 activity and decreased free radical levels in the cortex of mice compared to ConD and GFD. To probe the mechanism for the increased PON1 activity in mice, we studied the effect of Corinthian currant polar phenolic extract on PON1 activity secreted by Huh-7 hepatocytes or HEK293 cells transfected with a PON1-expressing plasmid. Incubation of cells with the extract led to a dose-dependent increase of secreted PON1 activity, which was attributed to increased cellular PON1 expression. Collectively, our findings suggest that phenolics in Corinthian currants can increase the hepatic expression and activity of antioxidant enzyme PON1 and that a Corinthian currant-supplemented diet during the early stages of AD in mice reduces brain oxidative stress.

The effect of meals rich in thermally stressed olive and safflower oils on postprandial serum paraoxonase activity in patients with diabetes

The effect of meals rich in thermally stressed olive and safflower oils on postprandial serum paraoxonase activity in patients with diabetes

Determination of Paraoxonase 1 Activity and Phenotype Distribution in Cervical Disk Herniation Patients

Determination of Paraoxonase 1 Activity and Phenotype Distribution in Cervical Disk Herniation Patients&#x0D; &#x0D; Abstract&#x0D; Objectives: Cervical disk herniation (CDH) is a common disease that usually develops as a result of intervertebral disk degeneration (IVDD) or trauma, which can cause pain or neurological deficiency by nevre root or spinal cord compression. Paraoxonase 1 (PON1) has antioxidant qualities, and its function may vary based on genetic variations and ethnic background. This study aims to compare PON1 activity and phenotype distribution in CDH patients and individuals without the condition.&#x0D; Materials and Methods: This study involved 70 CDH patients and 70 individuals in good health. Spectrophotometric tests were conducted to measure the serum PON1 and arylesterase (ARE) activities. The PON1 ratio, which indicates the salt-stimulated PON/ARE level, showed a three-peak distribution. This ratio was utilized to determine the various phenotypes; QQ, QR, and RR for each participant.&#x0D; Results: The PON1 activity was lower in CDH patients compared to the healthy individuals (p &lt; 0.05). CDH patients exhibited a statistically significant QQ phenotype in comparison to the healthy participants (p &lt; 0.05).&#x0D; Conclusion: Patients with CDH exhibited significantly reduced PON1 activity, indicating that low PON1 activity and the PON1 QQ phenotype could potentially be a risk factor for the development of CDH.&#x0D; Keywords: Cervical disk herniation, Paraoxonase, Phenotype, PON1

Pleiotropic functions and clinical importance of circulating HDL-PON1 complex.

High density lipoprotein (HDL) functions are mostly mediated through a complex proteome, particularly its enzymes. HDL can provide a scaffold for the assembly of several proteins that affect each other's function. HDL particles, particularly small, dense HDL3, are rich in paraoxonase 1 (PON1), which is an important enzyme in the functionality of HDL, so the antioxidant and antiatherogenic properties of HDL are largely attributed to this enzyme. There is an increasing need to represent a valid, reproducible, and reliable method to assay HDL function in routine clinical laboratories. In this context, HDL-associated proteins may be key players; notably PON1 activity (its arylesterase activity) may be a proper candidate because its decreased activity can be considered an important risk factor for HDL dysfunctionality. Of note, automated methods have been developed for the measurement of serum PON1 activity that facilitates its assay in large sample numbers. Arylesterase activity is proposed as a preferred activity among the different activities of PON1 for its assay in epidemiological studies. The binding of PON1 to HDL is critical for the maintenance of its activity and it appears apolipoprotein A-I plays an important role in HDL-PON1 interaction as well as in the biochemical and enzymatic properties of PON1. The interrelationships between HDL, PON1, and HDL's other components are complex and incompletely understood. The purpose of this review is to discuss biochemical and clinical evidence considering the interactions of PON1 with HDL and the role of this enzyme as an appropriate biomarker for HDL function as well as a potential therapeutic target.

Atipik Antipsikotiklerle Tedavi Sürecinde Görülen Hiperhomosisteinemi Metabolik Sendromdan Bağımsızdır

Strong association between homocysteine (Hcy) and metabolic syndrome (MetS) is documented in individuals with schizophrenia and it is suggested that alterations in Hcy levels might be secondary to metabolic changes induced by atypical antipsychotics (AA). Serum paraoxonase (PON-1) activity, which is negatively affected by increased Hcy concentrations are lower in schizophrenia, and this may impact the development of metabolic side effects. Forty-five subjects with schizophrenia and 43 healthy volunteers, matched according to age, gender, smoking habits, and MetS predictors, were enrolled in this study to examine how Hcy level, PON-1 activity, and MetS indicators influence each other in schizophrenic individuals on AA treatment. Serum Hcy concentrations were significantly higher (15 ± 8 μmol/L vs 12 ± 3 μmol/L), and PON activity tended to be impaired (182±82 U/L vs 216 ± 110 U/L) in schizophrenia. Serum Hcy concentrations were not different between subjects with and without metabolic syndrome in study (14±4 μmol/L and 16±9 μmol/L) and control groups (12±3 μmol/L and 13±7 μmol/L), respectively. Similarly, PON and aryl esterase (AE) activities were not different between subjects with and without metabolic syndrome in study (PON: 185±100 U/L and 181±76 U/L; AE: 84±34 kU/L and 89±20 kU/L) and control (PON: 215±111 U/L and 216±113 U/L; AE: 83±27 kU/L and 88±33 kU/L) groups, respectively. . Hcy levels and MetS predictors were not statistically correlated. Results indicate that schizophrenic subjects on AA treatment have increased levels of Hcy compared to healthy controls and this is not influenced by the presence of MetS.

Investigation of serum ischemic-modified albumin, galectin-3, paraoxonase-1, and myeloperoxidase activity levels in patients with acute brucellosis

ABSTRACTObjectives:Infection remains current as an important discussion topic in the etiological factors of atherosclerosis. Ischemic-modified albumin (IMA), galectin-3 (gal-3), paraoxonase-1 (PON-1), and myeloperoxidase (MPO) are biomolecules that play an important role in the pathogenesis of atherosclerosis. Our aim is to investigate serum IMA, gal-3, PON-1, and MPO activity in acute brucellosis infection.Materials and Methods:Forty patients with acute brucellosis and 40 healthy individuals were included in the study. Serum IMA, gal-3, PON-1, and MPO activity were analyzed by the ELISA method.Results:In acute brucellosis infection, serum gal-3, IMA, and MPO activities were found to be significantly increased compared to the control group, and PON-1 activity was found to be significantly decreased compared to the control group (p < 0.001). There was a positive correlation between serum IMA, and MPO activity (r = 0.707 p = 0.000) and a negative correlation (r = −0.943, p = 0.000) between PON-1 activity. There was a positive correlation between serum gal-3 and MPO activity (r = 0.683, p = 0.000) and IMA level (r = 0.927, p = 0.000) and a negative correlation between PON-1 activity (r = −0.951, p = 0.000).Conclusion, it was found that serum gal-3, IMA levels and MPO activity increased, while PON-1 activity decreased. These results showed that the oxidant-anti-oxidant balance is impaired in acute brucellosis infection. In addition, these results indicate that brucella infection may be increase the risk of atherosclerosis. Further studies are needed to support our findings.

Serum Arylesterase, Paraoxonase, and Lactonase Activities and Paraoxonase-1 Concentrations in Morbidly Obese Patients and Their Relationship with Non-Alcoholic Steatohepatitis.

Paraoxonase-1 (PON1) is an antioxidant enzyme associated with high-density lipoproteins (HDL). Reduced serum PON1 activity is found in diseases marked by oxidative stress and inflammation, but its role in obesity remains unclear. This study investigated PON1 activities and concentrations in morbidly obese individuals and explored the impacts of the genetic polymorphism PON1 rs662 and non-alcoholic fatty liver disease on enzymatic properties. We recruited 1349 morbidly obese patients undergoing bariatric surgery and 823 non-obese volunteers. PON1-related variables, including arylesterase, paraoxonase, and lactonase activities and PON1 concentrations, were examined. Our results showed that morbidly obese individuals exhibited higher PON1 concentrations but lower enzymatic activities than non-obese individuals. We observed inverse associations of arylesterase and paraoxonase activities with waist circumference (rho = -0.24, p < 0.001, and rho = -0.30, p < 0.001, respectively) and body mass index (rho = -0.15, p = 0.001, and rho = -0.23, p < 0.001), as well as direct associations of arylesterase, paraoxonase, and lactonase activities with HDL cholesterol (rho = 0.11, p = 0.005, rho = 0.20, p < 0.001, and rho = 0.20, p < 0.001). No significant differences were observed regarding metabolic syndrome, type 2 diabetes mellitus, hypertension, dyslipidemia, rs662 polymorphism allele frequencies, or the diagnosis of non-alcoholic steatohepatitis. Nevertheless, correlations were found between certain PON1-related variables, steatosis, and ballooning. In conclusion, changes in PON1-related variables in morbidly obese patients are dependent on the disease itself and HDL levels. The relationships between these variables and specific liver histological changes raise intriguing questions for consideration in future studies.

Evaluation of the myeloperoxidase/paraoxonase1 ratio as the determinant of dysfunctional HDL in polycystic ovary syndrome

Aim: The myeloperoxidase/paraoxonase1(MPO/PON1) ratio is known to reflect the dysfunctional HDL(d-HDL) which is a measure of oxidative stress. This study aimed to evaluate the MPO/PON1 ratio in polycystic ovary syndrome(PCOS).&#x0D; Materials and Method: This prospective study included a total of 123 patients. The study group including the women with the diagnosis of PCOS (n=63) was compared to the control group including the healthy women (n=60). Sociodemographic characteristics, and clinical features of the groups were recorded. Serum HDL level, MPO, and PON1 activities were evaluated.&#x0D; Results: The PCOS patients were observed to have increased MPO and decreased PON1 activities (p

Serum Activities of Paraoxonase 1 (PON1) in Predicting Liver Damage Among Patients Diagnosed With Hepatocellular Carcinoma: A Case-Control Study.

Introduction Hepatocellular carcinoma (HCC)is one of the most common cancers in the world and unless diagnosed timely has limited options for treatment. Paraoxonase(PON) isa glycosylated proteinthat has been implicated in antioxidant and other biochemical functions.Paraoxonase 1 (PON1)is an esterase associated with high-density lipoprotein (HDL) particles. The present study was carried out to assess the PON1 activity and compare it with the standard liver function tests (LFTs) in assessing the predictability of liver damage among patients diagnosed with HCC. Methods This case-control study was carried out in the Department of Biochemistry attached to Great Eastern Medical School and Hospital, Srikakulam, Andhra Pradesh. Serum PON1 activities and LFTs like total bilirubin, direct bilirubin, alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total protein, and albumin were estimated in 30 patients diagnosed with HCC and 30 healthy persons. All the parameters were estimated using standard biochemical methods.The data was analyzed using GraphPad Prism version 6.0 (GraphPad Software, Inc).A probability (p) value <0.05 was considered to be statistically significant. Receiver operating characteristic curve (ROC) analysis was performed to assess the area under the curve (AUC) for accuracy, sensitivity, specificity, and diagnostic efficiency. Results The serum activities of PON1 had identical sensitivity (70%) to albumin (70%) and were superior to other tested parameters. Additionally, PON1 activities showed lower specificity (86.67%) than the other tested parameters. ROC analysis showed increased diagnostic efficacy (DE) of PON1 (DE=78.3%; p<0.0001) when compared with total bilirubin (DE=76.6%; p=0.0039), direct bilirubin (DE=74.9%; p=0.04), ALT (DE=73.30%; p=0.0006), and total protein (DE=71.6%; p=0.0005). However, the DE of PON1 was comparable with AST (DE=81.60%; p<0.0001), ALP (DE=79.9%; p<0.0001), and albumin (DE=83.30%, p<0.0001). Conclusions Serum activities of PON1 could be used as a diagnostic marker for assessing liver damage among HCC patients.

Assessment of the Serum Paraoxonase1 Level and Its Relation to Total Oxidant Status and Disease Activity in Vitiligo Patients

Abstract Background Vitiligo is characterized by white macules and patches, whose size increases over time, due to the loss of melanocytes.It can appear at any time, and it significantly impairs the patients’ quality-of-life. Vitiligo is a multifactorial disorder due to genetic and environmental factors. One of the important hypotheses in the pathogenesis of vitiligo is the oxidative stress hypothesis, which is based on the reality of the formation of some toxic metabolites throughout pigment biosynthesis. Human paraoxonase-1 (PON1) is a Ca2+ dependent esterase synthesized in the liver. Reduced serum PON1 activity has been reported to be associated with some diseases under oxidative stress and inflammation conditions. Aim of the Work The aim of the work was to evaluate the serum level of paraoxonase1 in patients with vitiligo and its relation to total oxidant status and disease activity in vitiligous patients. Patients and Methods This is a case control study which included 48 vitiligo patients and 48 ageand sex-matched controls. The patients recruited from the Outpatient Dermatology Clinic at Ain Shams University Hospitals during the period from August 2020 till March 2021. Serum level of paraoxonase1 (PON1) and total oxidant status (TOS) where assessed by ELISA technique. Results We observed a statistically significant higher oxidative stress reflected by the high serum TOS levels among the vitiligo compared to controls. This finding supports the aforementioned hypothesis and it also came in accordance with the observations of high oxidative stress state in vitiligo patients which was repeatedly reported in many studies. Furthermore, we also reported the significant inverse relation between PON1 levels and the oxidative stress reflected by the serum TOS levels in vitiligo patients. This reflected the reduced protective antioxidant mechanisms in vitiligo patient making them more vulnerable to oxidative stress Conclusion Oxidative stress may play an important role in the pathogenesis of vitiligo. The finding of a PON1 decrease in vitiligo patients emphasises the underlying hypothesis in the progression of the disease, and it can highlight the effect of free radicals and leading oxidative damage in vitiligo disease. However, further, larger studies are necessary to confirm our results.

Hesperidin Supplementation Improves Altered PON -1, LDL Oxidation, Inflammatory Response and Hepatic Function in an Experimental Rat Model of Hyperlipidemia.

In this study, we have examined the effect of hesperidin on rats fed on an experimental high-fat diet. Male Wistar rats were given a high-fat diet orally for one month for developing an HFD (High fat- diet) model. Rats were also supplemented with hesperidin (100mg/kg body weight) for one month. We determined serum LDL (Low-density lipoprotein) oxidation, Paraoxonase-1 (PON-1) activity, and histopathological profile of the liver. Inflammatory cytokines levels were also measured in serum. HFD induced significant changes in LDL oxidation and PON-1 activity. Liver tissue histopathology and gene expression of inflammatory markers (Il-6(Interleukin-6), TNF- alpha (Tumor necrosis factor alpha), NF-KB (Nuclear factor kappa B) show that significant changes occur in the hyperlipidemic model of rats. We also show that hesperidin can effectively improve plasma antioxidant, LDL oxidation, and inflammatory cytokine expression in rats already subjected to hyperlipidemic stress. We conclude that hesperidin may protect the liver from oxidative stress by improving hepatic function.

Paraoxonase-1, a novel link between periodontitis and ischemic heart disease: A case-control study.

Periodontitis is a chronic inflammatory disease and might be a potential risk factor for ischemic heart disease (IHD). However, the link between periodontitis and atherosclerosis is not yet fully understood. Paraoxonase-1 (PON-1) is a new biomarker representing both anti-atherosclerotic and antioxidant activity, which also acts against dental biofilm formation and periodontitis. The possible contributing role of PON-1 in the relationship between periodontitis and atherosclerosis has not been studied to date. The aim of the present study was to investigate the serum level of PON-1 with regard to the periodontal status in IHD patients. In this case-control study, 67 patients with IHD underwent a periodontal examination and were accordingly allocated to one of the 2 study groups: the case group with chronic periodontitis (n = 36); or the control group with a healthy periodontium (n = 31). Serum PON-1 activity was measured by means of colorimetric analysis. There were no significant differences between the groups in terms of demographic data, cardiac risk factors, initial biochemical test results, cardiac pump function, and the number of grafted vessels. The activity of PON-1 in cardiac patients suffering from periodontitis was significantly lower than in cardiac patients with a healthy periodontal status (53.01 ±7.53 U/mL and 59.11 ±9.95 U/mL, respectively; p = 0.007). This finding suggests that the combination of IHD and periodontitis is associated with lower PON-1 activity. Further studies might be required to assess the possible role of periodontal treatment in increasing PON-1 activity and reducing IHD severity.

Serum paraoxonase activity in familial hypercholesterolaemia.

Serum paraoxonase activity in familial hypercholesterolaemia.

CAMEL MILK MODULATES LIPID METABOLISM, EXPRESSION OF ENZYMATIC ANTIOXIDANTS GENES AND PARAOXONASE ACTIVITY IN RATS FED HIGH CHOLESTEROL DIET

Current findings aimed to find out camel milk's effects on lipid metabolism, expression of the genes for antioxidant enzymes and paraoxonase-1 (PON-1) activity in rats fed diet-containing cholesterol 1%. Therefore, 30 rats were divided into three groups (10 rats per each). Rats of the first group, which acted as a control group, fed a basic diet. Rats of the second group fed a basal diet that included 1% cholesterol however, rats of the third group fed cholesterol 1% accompanied by oral administration of camel's milk (100mL/24h/cage/5 rats) as the only source of water for them. Diet of cholesterol 1% induced significant increase in serum total cholesterol, triacylglycerol (TAG), low-density lipoprotein cholesterol (LDL-c), alanine aminotransferase (ALT), aspartate aminotransferase (AST) activities whereas lower serum PON-1 activity was observed when compared to control. Diet of cholesterol 1% induced significant increase in hepatic Thiobarbituric acid reactive substance (TBARS) however, compared to the control, a significant decrease in the activity and gene expression of antioxidant enzymes such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione-S transferase (GST), and reduced glutathione (GSH) were detected. These detrimental effects were ameliorated into accepted range in camel milk treated group. Fatty degeneration and fatty cysts in liver tissues were detected in rats fed cholesterol diet but the affected liver showed acceptable degree of recovery in camel milk treated group. Conclusively, camel milk was potential for the treatment of hyperlipidemia and hypercholesterolemia in rats.

Paraoxonase 1 and Chronic Kidney Disease: A Meta-Analysis.

Oxidative stress is known to be associated with the pathophysiology of chronic kidney disease (CKD). Paraoxonase 1 (PON1) is an antioxidant enzyme that has been proposed as a biomarker for CKD. While several studies have reported an association between serum PON1 activity and CKD, consensus based on systematically analyzed data remains necessary. We set out to conduct a meta-analysis of literature on PON1 in CKD. Electronic databases, such as MEDLINE, Embase and CENTRAL, were searched for available studies on PON1 activity in patients with CKD (without dialysis) as published before December 2022. A random-effects meta-analysis was performed. In total, 24 studies (22 studies on paraoxonase and 11 on arylesterase activity) were eligibly identified. Patients with CKD showed a lower activity of paraoxonase (standard mean difference [SMD], -1.72; 95% confidence interval [CI], -2.15 to -1.29) and arylesterase (SMD, -2.60; 95%CI, -3.96 to -1.24) than healthy controls. In the subgroup analyses, paraoxonase activity was lower in chronic kidney failure (CKF), an advanced stage of CKD, than in non-CKF. In summary, PON1 activity is low in patients with CKD, suggesting that the antioxidant defense by PON1 is impaired in CKD. The decrease in enzyme activity is pronounced in advanced CKD showing some variability depending on the substrate employed to measure PON1 activity. Further studies are warranted.