Frequency of Human Paraoxonase-1 Q192R Polymorphism and Measurement of Oxidative Stress Parameters in Infants with G6PD Deficiency

Author(s):  
Vahid Pourshafiei ◽  
Vahide Jamshidi ◽  
Ameneh Khodarahmi ◽  
Mahmood Vakili

Background and Aims: This study aimed to investigate the frequency of Q192R polymorphism and oxidative stress markers in infants with glucose-6phosphate dehydrogenase (G6PD) deficiency. Materials and Methods: This is a case-control study in which 60 male infants (2-4 months old) with G6PD deficiency along with 60 age- and sexmatched healthy neonates were included. The diagnosis of G6PD deficiency was made by Beutler test by which the G6PD enzyme activity is measured by the fluorescent spot test. The blood samples were taken from all infants, and the sera were isolated for the evaluation of Paraoxonase-1 (PON1) and malondialdehyde (MDA) using the spectrophotometric method. Restriction fragment length polymorphism was applied for determination of Q192R polymorphism (rs 662). Results: The frequencies of QQ, QR, and RR genotypes were 55%, 39%, and 6%, respectively in infants with G6PD deficiency while the above genotype frequencies were 45%, 49%, and 6%, respectively in healthy neonates. The frequency of R and T alleles failed to show any significant difference when G6PD deficient infants and healthy neonates were compared. The results indicated PON1 activity and MDA levels being significantly (p<0.05) higher in neonates with G6PD deficiency compared with their healthy counterparts. Conclusion: Contrary to previous studies, it was indicated that the presence of RQ and RR genotypes at Q192R position is associated with decreased activity of PON1 and increased oxidative stress. In this study, no significant differences were found in the genotype and allele frequency of PON1 Q192R polymorphism between the case and control groups. Also, this frequency was not consistent with the results obtained from oxidative stress conditions.

2013 ◽  
Vol 141 (9-10) ◽  
pp. 629-633 ◽  
Author(s):  
Ivana Grubisa ◽  
Petar Otasevic ◽  
Nada Dimkovic ◽  
Ivana Nedeljkovic ◽  
Bosko Toljic ◽  
...  

Introduction. Paraoxonase 1 (PON1) is a multifunctional enzyme associated with high-density lipoprotein particles (HDL). It is a cellular antioxidant that hydrolyses oxidized macromolecules, especially low-density lipoproteins (ox-LDL). Because increased oxidative stress is believed to play a crucial role in the initiation and propagation of atherosclerosis, coding (Q192R and L55M) and promoter (C(-107)T) region polymorphisms of pon1 gene, that are responsible for catalytic efficiency, activity and the level of the enzyme, have been of great interest as a potential markers of susceptibility for atherogenesis. Objective. The aim of the study was to assess possible association between these pon1 gene variants and clinical manifestations of the atherosclerosis and oxidative stress. Methods. A total of 60 angiographically documented patients with manifested atherosclerotic disease and 100 control individuals were analyzed. Genomic DNA was isolated from the peripheral blood cells and genotyping was performed using polymerase chain reaction followed by the restriction fragment length polymorphism (PCR-RFLP) analysis. Results No significant difference in allele and genotype frequencies of all three examined polymorphisms was found between the atherosclerotic patients and healthy controls. The obtained results could not support an association of pon1 gene variants with the oxidative stress and atherogenesis. Conclusion. These polymorphisms cannot be considered risk factors of atherosclerosis in Serbian population. A larger study is required in order to establish possible contribution of pon1 variants to atherosclerosis-related cardiovascular diseases.


2018 ◽  
Vol 4 (3) ◽  
pp. 21-26
Author(s):  
Kar Param ◽  
Mohod Kanchan ◽  
Puttewar Manish ◽  
Kumar Satish

Background:  Oral  premalignancies  are  a  group  of  disease  or  syndromes  which  if  left untreated can lead to cancer. It carries a great significance in Indian perspective. The actual figure  of  oral  cancers  arising  from  oral  premalignancies  is  not  known  and  to  predict accurately the malignant transformations of them is still not possible. Oxidative stress is a known player behind cancerogenesis.  Recently decreased Paraoxonase-1 activity and increased oxidative stress markers ware found to be associated with Oral Squamous Cell Carcinoma. So, there is a strong possibility of a similar finding in Oral Premalignancies too. Aim:  This study aims to investigate the correlation between serum PON-1 activity and oxidative stress markers (MDA & Vitamin C) in patients with Oral Premalignancies. Material and Methods: A total of 62 patients with clinically diagnosed oral premalignant lesions and diseased controls were chosen for the study.  Venous blood samples were collected and PON-1, MDA (in serum) & Vitamin c (in plasma) were analysed spectro-photometrically. Results:   A   significant   decreased   serum   PON-1   activity   (P<0.05)   and   concomitant significantly increased serum MDA (P <0.05) and decreased Vitamin C levels (P<0.05) were observed in premalignancies compared to the controls. These finding were more pronounced in Oral Leukoplakia (OL) than in Oral Submucous Fibrosis (OSMF) with a significant difference. Mean levels of the analysed parameters differed accordingly in the clinical grades of oral premalignancies. Conclusion: It can be envisaged that serum PON-1 activity and increased oxidative stress might be a contributing factor behind pathogenesis and progression of Oral Premalignant Diseases.


2020 ◽  
Vol 16 (5) ◽  
pp. 743-748
Author(s):  
Ana R.S. de Oliveira ◽  
Kyria J.C. Cruz ◽  
Jennifer B.S. Morais ◽  
Juliana S. Severo ◽  
Jéssica B. Beserra ◽  
...  

Background: The role of minerals in preventing the generation of oxidative stress in obese individuals has been evaluated. Magnesium is an antioxidant nutrient and a cofactor of enzymes involved in the cell membrane stabilization, attenuating the effects of oxidative stress. Objective: To evaluate the association between magnesium and concentrations of thiobarbituric acid reactive substances (TBARS) in patients with obesity and eutrophic women. Methods: A cross-sectional study was conducted with 73 women, divided into two groups: case group (patients with obesity, n=27) and control group (eutrophic women, n=46). Measurements of body mass index and waist circumference were performed. Dietary magnesium intake was assessed by the three-day food record using the NutWin software. Urinary magnesium concentration was measured by atomic absorption spectrophotometry method. Plasma concentrations of thiobarbituric acid reactive substances (TBARS) were also determined. Results: Mean values of dietary magnesium intake were 161.59 ± 60.04 and 158.73 ± 31.96 for patients with obesity and control group, respectively, with no significant difference between the groups studied (p >0.05). The value of urinary excretion of magnesium was lower than the reference values in both groups, with no significant difference between the groups studied (p >0.05). The plasma concentration of thiobarbituric acid reactive substances was significantly higher in patients with obesity compared to the control group (p <0.001). There was no correlation between levels of magnesium biomarkers and the concentration of TBARS (p >0.05). Conclusion: Patients with obesity showed a reduced dietary magnesium intake which seems to induce hypomagnesuria as a compensatory mechanism. The marker of oxidative stress evaluated in this study was not influenced by magnesium.


2018 ◽  
Vol 44 (4) ◽  
pp. 530-538
Author(s):  
Aysun Çetin ◽  
İhsan Çetin ◽  
Semih Yılmaz ◽  
Ahmet Şen ◽  
Göktuğ Savaş ◽  
...  

Abstract Background Limited research is available concerning the relationship between oxidative stress and inflammation parameters, and simultaneously the effects of rosuvastatin on these markers in patients with hypercholesterolemia. We aimed to investigate the connection between cytokines and oxidative stress markers in patients with hypercholesterolemia before and after rosuvastatin treatment. Methods The study consisted of 30 hypercholesterolemic patients diagnosed with routine laboratory tests and 30 healthy participants. The lipid parameters, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), paraoxonase-1 (PON1) and malondialdehyde (MDA) levels in controls and patients with hypercholesterolemia before and after 12-week treatment with rosuvastatin (10 mg/kg/day), were analyzed by means of enzyme-linked immunosorbent assay. Results It was found that a 12-week cure with rosuvastatin resulted in substantial reductions in IL-1β, IL-6 and TNF-α and MDA levels as in rising activities of PON1 in patients with hypercholesterolemia. Before treatment, the PON1 levels were significantly negatively correlated with TNF-α and IL-6 in control group, while it was positively correlated with TNF-α in patients. Conclusion Our outcomes provide evidence of protected effect of rosuvastatin for inflammation and oxidative damage. It will be of great interest to determine whether the correlation between PON1 and cytokines has any phenotypic effect on PON1.


2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Chandrakala Aluganti Narasimhulu ◽  
Dmitry Litvinov ◽  
Danielle Jones ◽  
Chittoor Sai-Sudhakar ◽  
Michael Fristenberg ◽  
...  

Hypothesis: Oxidized low density lipoprotein (Ox-LDL) has properties that profoundly affect cardiovascular function. We hypothesized that Ox-LDL is likely to be formed in the left ventricular blood (LVB) when the heart is subjected to ischemic conditions and the ejection fraction (EF) is low. We speculated whether “stagnation” of LDL in the LV could result in increased formation of Ox-LDL. Objective: We studied whether there is an increased level of Ox-LDL in the LVB as opposed to peripheral blood (PB), and whether its presence correlated with the EF. Also we examined whether a higher level of Ox-LDL negatively correlated with the activity of paraoxonase 1 (PON 1). Methods: Following the Institutional Review Board (IRB) approval, 62 HF patients were enrolled in the study. All patients underwent pre-operative transthoracic echocardiographic assessment of ventricular function. Left ventricular ejection fractions were determined using the Simpsons bi-plane technique. 2ml of LVB and 5ml of PB samples were taken before coronary artery bypass surgery, or a surgery with replacement of mitral, aortic or tricuspid valve. Blood level of Ox-LDL was determined by ELISA (Mercodia), and PON 1 activity was determined by the rate of conversion of its substrate p-nitrophenyl acetate into p-nitrophenol. Results: The result showed significant increase in Ox-LDL in LVB as compared to PB (p=0.032) in HF subjects even when EF was near normal. There was no significant increase in subjects with lower EF. In contrast, Ox-LDL levels increased in the PB of subjects with lower EF and reached those of LVB. We also noticed that there was a statistically significant negative correlation between EF and Ox-LDL levels in both LVB and PB (p < 0.05). The activity of PON1, an antioxidant enzyme that protects LDL from oxidation showed decreased levels both in LV blood as well as in PB with decreased EF. It was observed that there was a statistically significant difference in PON1 levels between LV and PB of subjects having EF>60% (p = 0.03). Conclusions: In conclusion the results suggest that there might be oxidative stress associated with LVB even when the EF is not compromised. In contrast, the increase in PB Ox-LDL with poor EF might suggest that the low blood flow to peripheral tissues and end organs also might contribute to increased oxidative stress. The results also might suggest that persistent oxidative stress could have affected the clearance mechanisms of Ox-LDL.


2021 ◽  
Vol 11 ◽  
Author(s):  
Omar M.E. Abdel-Salam ◽  
Eman R. Youness ◽  
Nadia A. Mohammed ◽  
Amr M.M. Ibrahim

Systemic inflammation causes brain oxidative stress, a prerequisite for neurodegeneration. In this study, we investigated the effect of the anesthetic agents propofol and fentanyl on brain oxidative stress during mild systemic endotoxemia induced by lipopolysaccharide (LPS) endotoxin. For this purpose, rats were administered LPS (400 μg/kg, intraperitoneally; i.p.), treated at the same time with different doses of propofol or fentanyl, i.p., and euthanized 4 h later. Other groups were treated with the saline, only propofol, or only fentanyl. Oxidative stress markers including malondialdehyde (MDA), nitric oxide (NO), and reduced glutathione (GSH) were determined. In addition, nuclear factor kappaB (NF-kB), paraoxonase-1 (PON-1), and butyrylcholinesterase (BChE) activities were measured in the brain tissue. Results showed that compared with the saline group, administration of LPS caused a marked and significant increase in brain MDA and NO combined with depletion of GSH and decreased PON-1 and BChE activities. Additionally, the active form of NF-kB was significantly increased in the brain of LPS only-treated rats. Treatment with propofol or fentanyl led to a marked and significant decrease in the levels of brain MDA and NO together with a significant increase in GSH and restoration of PON-1 and BChE activities. Furthermore, lower levels of active form of NF-kB were found following treatment with propofol or fentanyl compared with those in the LPS only group. Collectively, these results suggest that propofol and fentanyl exhibit an antioxidant action and attenuate the endotoxin-induced brain oxidative stress.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Rakesh S Birjmohun ◽  
Menno Vergeer ◽  
Erik S Stroes ◽  
Michael W Tanck ◽  
Nicholas J Wareham ◽  
...  

Background Paraoxonase-1 (PON1) is a potent antioxidant enzyme bound to high-density lipoprotein (HDL). Its activity, but not its concentration, is controlled by the PON1 Q192R polymorphism. PON1 is considered to protect against atherogenesis, but it is unclear whether this relation is independent of its carrier, HDL. Objective To evaluate the predictive value of PON1 for coronary artery disease (CAD) we assessed PON1 activity and genotype (Q192R polymorphism) in a large cohort. Methods and results We performed a case-control study nested in the prospective EPIC-Norfolk cohort. Cases (n = 1138) were apparently healthy men and women aged 45–79 years who developed fatal or nonfatal CAD during a mean follow-up of 6 years. Controls (n=2237) were matched by age and sex. Serum PON1 activity was lower in cases vs. controls (59.9 ± 44.6 U/L vs. 63.4 ± 46.7 U/L, p=0.020) and correlated with HDL cholesterol (r= 0.16, p<0.0001). Whereas the PON1 Q192R polymorphism strongly controlled PON1 activity (QQ: 27 ± 9, QR: 87 ± 27 and RR 152 ± 44 U/L), it was not related to the risk of future CAD (Odds Ratio [OR] per R allele 0.98 [0.84–1.15], p=0.84). Using conditional logistic regression, quartiles of PON1 activity showed a modest inverse relation with CAD risk (OR for the highest vs. the lowest quartile 0.77 [0.63– 0.95], p=0.013; p for trend over quartiles 0.064). PON1 activity adjusted for Q192R genotype - a proxy for PON1 concentration -correlated better with HDL cholesterol (r=0.29, p<0.0001) and strongly predicted CAD risk (OR for the highest versus the lowest quartile 0.72 (0.58 – 0.91), p for trend over quartiles = 0.005). However, this relation was abolished after adjustment for HDL related parameters (HDL particle number, HDL cholesterol, HDL size and apolipoprotein A-I; OR for highest vs. lowest quartile 0.87 [0.66 –1.16], p for trend over quartiles = 0.13). Conclusion In the largest prospective study to date, we show that PON1 activity inversely relates to CAD risk, but not independently of HDL, presumably due to its close association with the HDL particle. Since the Q192R polymorphism profoundly affects lifelong PON1 activity, our inability to demonstrate a relation between the Q192R polymorphism and CAD risk suggests that PON1 activity is not a causal factor in atherogenesis.


1994 ◽  
Vol 40 (12) ◽  
pp. 2235-2239 ◽  
Author(s):  
M Y Tsai ◽  
N Q Hanson ◽  
K R Copeland ◽  
I Beheshti ◽  
U Garg

Abstract We used the amplification refractory mutation system (ARMS)--a polymerase-chain-reaction-based method--to determine the 3206 T-to-G polymorphism on exon 4 of the apolipoprotein (apo) C III gene. Apo C III is an inhibitor of the enzyme lipoprotein lipase (EC 3.1.1.34). Previous studies have demonstrated that a polymorphism at nucleotide 3175 on exon 4 of this gene is associated with hypertriglyceridemia. We studied 45 hypertriglyceridemic and 46 age-matched controls for the 3206 T-to-G polymorphism. The results showed a significant difference in the distribution of the genotypes with respect to this allele between the hypertriglyceridemic and control individuals. We also determined the presence of the SacI site at nucleotide 3175 in these same individuals and found no significant difference in SacI genotypes between the two groups. This study reaffirms the usefulness of ARMS as a simple, reliable method for detecting mutations and polymorphisms in clinical and epidemiological studies.


2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Małgorzata Trocha ◽  
Małgorzata Krzystek-Korpacka ◽  
Anna Merwid-Ląd ◽  
Beata Nowak ◽  
Małgorzata Pieśniewska ◽  
...  

Purpose. Ischemia/reperfusion (IR) is the main cause of liver damage after transplantation. We evaluated the effect of sitagliptin (STG) on oxidative stress parameters in the rat liver under IR. Methods. Rats were treated with STG (5 mg/kg) (S and SIR) or saline solution (C and CIR). Livers from CIR and SIR were subjected to ischemia (60 min) and reperfusion (24 h). During reperfusion, aminotransferases (ALT and AST) were determined in blood samples. Thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), paraoxonase-1 (PON1), glutathione peroxidase (GPx), and the mRNA expression of SOD1 were determined in liver homogenates after reperfusion. Different regions of livers were also histologically evaluated. Results. The PON1 activity was higher, and the TBARS level was lower in SIR than in CIR. There was an inverse relationship between TBARS and PON1 levels in the whole cohort. The GPx activity was lower in ischemic than in nonischemic groups regardless of the STG treatment. In SIR, the SOD1 activity was higher compared to that in CIR. In S, the expression of SOD1 mRNA was the highest of all examined groups and positively correlated with the SOD1 activity in the whole animal cohort. During IR aminotransferases, the activity in the drug-treated group was lower in all examined points of time. In drug-treated groups, the percentage of steatosis was higher than that in nontreated groups regardless of IR. Conclusions. The protective effect of STG on the rat liver, especially its antioxidant properties, was revealed under IR conditions.


1988 ◽  
Vol 71 (2) ◽  
pp. 333-336
Author(s):  
Dave Wotherspoon ◽  
Ralph Hindle

Abstract A quick method for determining /V-nitrosodipropylamine (NDPA) levels in trifluralin emulsifiable concentrate formulations is described. At least 18 samples can be analyzed at one time in a minimum of fumehood space, with up to 90% savings on solvents and materials. A sample aliquot is mixed with a solution containing nitrosamine recovery standards, and nitrosamines are separated by minicolumn cleanup. Internal standard is added directly to the eluate containing the nitrosamines, and levels are determined by gas chromatography with thermal energy analyzer. Recoveries of spiked nitrosamines ranged from 98 to 102%. Coefficients of variation for samples containing 0.5 ppm NDPA are 13%. Minimum detectable limit, calculated as 3 times the noise, is 0.06 ppm. Comparison with the method formerly used by this laboratory shows no significant difference in the analytical results at 95% confidence limits, and control experiments were performed to ensure that there was no artifact formation of NDPA.


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