Distribution Spectrum of Paraoxonase Activity in HDL Fractions

Abstract Background: Paraoxonase (PON1) associated with HDL can be regarded as a cardio- and vasoprotective enzyme. However, because HDL is not a homogeneous fraction, it is important to investigate in which subgroups of HDL active PON1 is located. It would also be useful to determine density profiles of the HDL apolipoproteins (Apo) E and J. Methods: We investigated the density range of HDL (ρ = 1.063–1.256 kg/L) in healthy individuals, using the ultracentrifugation reference method and a newly introduced automated fractionation method. Profiles of PON1 activity and ApoA-I, ApoA-II, ApoE, ApoJ, and cholesterol concentrations were obtained by use of various density gradients. Results: PON1 activity was highest in the more dense HDL3 and VHDL fractions where PON1 was not dissociated from the particles during centrifugation. The fraction in density range 1.175–1.185 kg/L showed not only the highest PON1 activity, but also the highest specific activity (activity per HDL particle). This fraction was the least-dense fraction containing both ApoE and ApoJ. Only the Q192R polymorphism had an effect on the distribution profile of PON1 activity. In contrast, L55M and the T(−107)C polymorphisms (determined by a novel nonradioactive method) were without effect on the density distribution of PON1 activity. Conclusion: The HDL3 fraction, which is important in reverse cholesterol transport, also carries the highest PON1 activity.

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Abstract 3132: Paraoxonase-1 Activity Is not Independently Related with the Risk of Future Coronary Artery Disease

Circulation ◽

10.1161/circ.118.suppl_18.s_1099 ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Rakesh S Birjmohun ◽

Menno Vergeer ◽

Erik S Stroes ◽

Michael W Tanck ◽

Nicholas J Wareham ◽

...

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Close Association ◽

Conditional Logistic Regression ◽

Hdl Cholesterol ◽

Paraoxonase 1 ◽

Pon1 Activity ◽

Q192r Polymorphism ◽

Artery Disease ◽

Cad Risk

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.

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Paraoxonase (Pon1) Q192R polymorphism and serum Pon1 activity in diabetic patients on maintenance hemodialysis

Clinical Nephrology ◽

10.5414/cnp60257 ◽

2003 ◽

Vol 60 (10) ◽

pp. 257-265 ◽

Cited By ~ 11

Author(s):

B. Zhang ◽

S. Eto ◽

P. Fan ◽

C. Bian ◽

E. Shimoji ◽

...

Keyword(s):

Pon1 Activity ◽

Maintenance Hemodialysis ◽

Diabetic Patients ◽

Q192r Polymorphism ◽

Serum Pon1 Activity

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The assessment of total energy expenditure of female farmers under field conditions

Journal of Biosocial Science ◽

10.1017/s002193200001988x ◽

1992 ◽

Vol 24 (3) ◽

pp. 325-333 ◽

Cited By ~ 6

Author(s):

Thierry Brun

Keyword(s):

Developing Countries ◽

Energy Expenditure ◽

Rural Women ◽

Specific Activity ◽

Reference Method ◽

Repeated Measurements ◽

Field Conditions ◽

Female Population ◽

Female Farmers ◽

The Cost

SummaryThe paper reviews methods, and their difficulties, in the measurement of the daily energy expenditure of rural women under field conditions in developing countries. Since all methods need to be validated against a reference method which is usually based on indirect calorimetry, examples of the use of this technique are given. The energy costs of most agricultural and daily tasks of rural women in developing countries have been measured. Large intra- and inter-individual variations in the cost of a single activity occur, so repeated measurements are needed to obtain a valid mean energy cost for a specific activity for a homogeneous group of individuals.Much work remains to be done on the assessment of the duration and the intensity of the physical activity of the rural adolescent and adult female population. Studies indicate that the workload of most rural women in developing countries is excessive and frequently associated with acute poverty.

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

International Journal of Medical Laboratory ◽

10.18502/ijml.v7i2.2915 ◽

2020 ◽

Author(s):

Vahid Pourshafiei ◽

Vahide Jamshidi ◽

Ameneh Khodarahmi ◽

Mahmood Vakili

Keyword(s):

Oxidative Stress ◽

G6pd Deficiency ◽

Paraoxonase 1 ◽

Pon1 Activity ◽

Stress Markers ◽

Genotype Frequencies ◽

Q192r Polymorphism ◽

Significant Difference ◽

And Control

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.

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Characterization of Apolipoprotein E-containing Lipoproteins in Cerebrospinal Fluid: Effect of Phenotype on the Distribution of Apolipoprotein E

Clinical Chemistry ◽

10.1093/clinchem/45.9.1431 ◽

1999 ◽

Vol 45 (9) ◽

pp. 1431-1438 ◽

Cited By ~ 21

Author(s):

Kazuyoshi Yamauchi ◽

Minoru Tozuka ◽

Hiroya Hidaka ◽

Eiko Hidaka ◽

Yoshiyuki Kondo ◽

...

Keyword(s):

Cerebrospinal Fluid ◽

Apolipoprotein E ◽

Gel Filtration ◽

Distribution Profile ◽

Serum Fractions ◽

Apo E ◽

The Central Nervous System ◽

Unique Composition ◽

Apoe Phenotype

Abstract Background: Apolipoprotein (apo) E, one of the main apolipoproteins in the central nervous system, may play an important role in lipid metabolism; however, the details of its function are poorly understood. In this study, we characterized apoE-containing lipoproteins in cerebrospinal fluid (CSF) and examined the effect of apoE phenotype on the distribution of apoE among the lipoprotein fractions. Methods: CSF lipoproteins were fractionated by gel filtration and ultracentrifugation, and then characterized by electrophoresis, immunoblot, electron microscopy, and analysis of apoE, total cholesterol, and phospholipid concentrations. Results: The ratio of sialylated to nonsialylated apoE was higher in CSF than in serum. However, the fundamental forms containing apoE homodimers or heterodimers [such as apo(E-AII) and apo(AII-E2-AII) complexes] were similar in CSF and serum. apoE-containing lipoproteins were fractionated at densities of <1.006, 1.063–1.125, and 1.125–1.21 kg/L. Neither apoE nor apoAI was detected in the fraction with a density range of 1.006–1.063 kg/L. The diameters of the lipoprotein particles with densities of <1.006, 1.063–1.125, and 1.125–1.21 kg/L were 16.7 ± 3.1, 14.0 ± 3.2, and 11.6 ± 2.8 nm (mean ± SD, n = 200), respectively. All of these lipoproteins exhibited a spherical structure. The distribution profile of apoE-containing lipoproteins was affected by the apoE phenotype. A relatively large amount of apoE-containing lipoproteins was isolated from the fraction with a density >1.125 kg/L obtained from CSF associated with apoE2 or apoE3. This tendency was more obvious in CSF associated with apoE2 than in CSF without apoE2. apoE-containing lipoproteins were predominantly observed in the fraction with a density of <1.006 kg/L obtained from CSF associated with apoE4. Conclusions: The lipoproteins in CSF have a unique composition that is different from that of the lipoproteins in plasma. However, the differences in diameter between the CSF fractions were not as large as for the serum fractions. Our data suggest that the apoE phenotype may affect the distribution profile of apoE-containing lipoproteins in the CSF. This would mean that the metabolism of apoE-containing lipoproteins depends on the apoE isoform present.

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Isolasi dan Karakterisasi Enzim Bromelain dari Bonggol dan Daging Buah Nanas (Ananas comosus)

Chemica: Jurnal Ilmiah Kimia dan Pendidikan Kimia ◽

10.35580/chemica.v21i2.17983 ◽

2020 ◽

Vol 21 (2) ◽

pp. 133

Author(s):

Nita Magfirah Ilyas

Keyword(s):

Thermal Stability ◽

Ammonium Sulfate ◽

Specific Activity ◽

Crude Enzyme ◽

Ananas Comosus ◽

Optimum Temperature ◽

The Core ◽

Purity Level ◽

Pineapple Fruit ◽

Fractionation Method

Penelitian ini bertujuan untuk mengisolasi dan memurnikan bromelain yang diekstrak dari bagian tanaman nanas (Ananas comosus) melalui metode fraksinasi menggunakan garam ammonium sulfat, diikuti dengan proses dialisis. Aktivitas spesifik tertinggi terdapat pada fraksi ammonium sulfat 50-80% (fraksi 3) baik untuk sampel bagian bonggol maupun bagian daging buah nanas, masing-masing adalah sebesar 0,30 U/mg dan 0,21 U/mg. Fraksi 3 dari bagian bonggol memiliki tingkat kemurnian 132,65 kali enzim kasarnya sedangkan fraksi 3 dari bagian daging buah nanas memiliki tingkat kemurnian 108,47 kali dari enzim kasarnya. Proses dialisis memberikan nilai aktivitas spesifik dan tingkat kemurnian enzim tertinggi pada fraksi 3 dari bagian bonggol nanas yaitu sebesar 0,33 U/mg dengan kenaikan tingkat kemurnian menjadi sebesar 141,58 kali enzim kasarnya. Uji kestabilan termal terhadap fraksi enzim hasil dialisis menunjukkan bromelain dari bonggol memiliki kestabilan termal yang lebih tinggi dibandingkan dengan bromelain dari daging buah nanas. pH dan suhu optimum dari enzim bromelain adalah 7,0 dan 37oC. Kata kunci: Ananas comosus, bonggol nanas, bromelain, aktivitas spesifik, pemurnian ABSTRACT The aim of this study was to isolate and purify the bromelain extracted from part of pineapple fruit (Ananas comosus) through fractionation method using ammonium sulfate followed by dialysis. The highest specific activity on ammonium sulfate fraction was 50-80% (fraction 3) both for the sample of the core and the flesh of pineapple, each was 0.30 U/mg and 0.21 U/mg. The fraction 3 of the core had a purity level 132.65 times of the crude enzyme while fraction 3 of the pineapple flesh had a purity level 108.47 times of the crude enzyme. From the dialysis process found the highest value of specific activity on fraction 3 of the pineapple core of 0.33 U/mg with a purity level of and 141.58 times of the crude enzyme. Fraction of the core has higher thermal stability than the fraction of the flesh. The optimum temperature and pH of this enzyme was 37oC and 7.0. Keywords: Ananas comosus, pineapple core, bromelain, specific activity, purification

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Carnitine biosynthesis. Hydroxylation of N6-trimethyl-lysine to 3-hydroxy-N6-trimethyl-lysine

Biochemical Journal ◽

10.1042/bj1880529 ◽

1980 ◽

Vol 188 (2) ◽

pp. 529-534 ◽

Cited By ~ 33

Author(s):

D S Sachan ◽

C L Hoppel

Keyword(s):

Protein Concentration ◽

Citrate Synthase ◽

Specific Activity ◽

Rat Kidney ◽

Fold Increase ◽

Hydroxylase Activity ◽

Distribution Profile ◽

Bivalent Cations ◽

Mitochondrial Distribution ◽

Distribution Studies

Rat kidney homogenates metabolize N6-trimethyl-lysine to N-trimethylammoniobutyrate, but not to carnitine. The first step in this conversion is the hydroxylation of trimethyl-lysine to form 3-hydroxy-N6-trimethyl-lysine. An assay system was developed in which hydroxylation of trimethyl-lysine is linear with respect to both time and homogenate protein concentration. The rate is 5 nmol of 3-hydroxy-N6-trimethyl-lysine formed/min per mg of homogenate protein. The cofactors required are ascorbate, alpha-oxoglutarate, FeSO4, and O2. Catalase and dithiothreitol give a 20% stimulation. Ca2+ produces a 2-fold increase in specific activity and cannot be replaced by Mg2+, Mn2+ or Zn2+. These last three bivalent cations lead to a decreased activity. Subcellular distribution studies demonstrate that trimethyl-lysine hydroxylase activity parallels the distribution profile of succinate dehydrogenase and citrate synthase. Thus trimethyl-lysine hydroxylase has a mitochondrial localization. Distribution of trimethyl-lysine hydroxylase activity between cortex and medulla of kidney if 67 and 33% respectively, similar to mitochondrial distribution.

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Why Should Psychiatrists and Neuroscientists Worry about Paraoxonase 1?

Current Neuropharmacology ◽

10.2174/1570159x17666181227164947 ◽

2019 ◽

Vol 17 (11) ◽

pp. 1004-1020 ◽

Cited By ~ 9

Author(s):

Estefania Gastaldello Moreira ◽

Karine Maria Boll ◽

Dalmo Guilherme Correia ◽

Janaina Favaro Soares ◽

Camila Rigobello ◽

...

Keyword(s):

Clinical Trials ◽

Drug Targets ◽

Paraoxonase 1 ◽

Pon1 Activity ◽

Psychiatric Diseases ◽

Physically Active ◽

Effective Strategies ◽

Q192r Polymorphism ◽

Pubmed Database ◽

Pon1 Polymorphisms

Background: Nitro-oxidative stress (NOS) has been implicated in the pathophysiology of psychiatric disorders. The activity of the polymorphic antioxidant enzyme paraoxonase 1 (PON1) is altered in diseases where NOS is involved. PON1 activity may be estimated using different substrates some of which are influenced by PON1 polymorphisms. Objectives: 1) to review the association between PON1 activities and psychiatric diseases using a standardized PON1 substrate terminology in order to offer a state-of-the-art review; and 2) to review the efficacy of different strategies (nutrition, drugs, lifestyle) to enhance PON1 activities. Methods: The PubMed database was searched using the terms paraoxonase 1 and psychiatric diseases. Moreover, the database was also searched for clinical trials investigating strategies to enhance PON1 activity. Results: The studies support decreased PON1 activity as determined using phenylacetate (i.e., arylesterase or AREase) as a substrate, in depression, bipolar disorder, generalized anxiety disorder (GAD) and schizophrenia, especially in antipsychotic-free patients. PON1 activity as determined with paraoxon (i.e., POase activity) yields more controversial results, which can be explained by the lack of adjustment for the Q192R polymorphism. The few clinical trials investigating the influence of nutritional, lifestyle and drugs on PON1 activities in the general population suggest that some polyphenols, oleic acid, Mediterranean diet, no smoking, being physically active and statins may be effective strategies that increase PON1 activity. Conclusion: Lowered PON1 activities appear to be a key component in the ongoing NOS processes that accompany affective disorders, GAD and schizophrenia. Treatments increasing attenuated PON1 activity could possibly be new drug targets for treating these disorders.

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Q192R polymorphism of the paraoxonase-1 gene as a risk factor for obesity in Portuguese women

Acta Endocrinologica ◽

10.1530/eje-10-0825 ◽

2011 ◽

Vol 164 (2) ◽

pp. 213-218 ◽

Cited By ~ 21

Author(s):

Luísa Veiga ◽

José Silva-Nunes ◽

Alice Melão ◽

Ana Oliveira ◽

Leone Duarte ◽

...

Keyword(s):

Risk Factor ◽

Public Health Problem ◽

Premenopausal Women ◽

Normal Weight ◽

Paraoxonase 1 ◽

Pon1 Activity ◽

Major Public Health Problem ◽

Obese Women ◽

Q192r Polymorphism ◽

Increased Risk

IntroductionObesity became a major public health problem as a result of its increasing prevalence worldwide. Paraoxonase-1 (PON1) is an esterase able to protect membranes and lipoproteins from oxidative modifications. At the PON1 gene, several polymorphisms in the promoter and coding regions have been identified. The aims of this study were i) to assess PON1 L55M and Q192R polymorphisms as a risk factor for obesity in women; ii) to compare PON1 activity according to the expression of each allele in L55M and Q192R polymorphisms; iii) to compare PON1 activity between obese and normal-weight women.Materials and methodsWe studied 75 healthy (35.9±8.2 years) and 81 obese women (34.3±8.2 years). Inclusion criteria for obese subjects were body mass index ≥30 kg/m2 and absence of inflammatory/neoplasic conditions or kidney/hepatic dysfunction. The two PON1 polymorphisms were assessed by real-time PCR with TaqMan probes. PON1 enzymatic activity was assessed by spectrophotometric methods, using paraoxon as a substrate.ResultsNo significant differences were found for PON1 activity between normal and obese women. Nevertheless, PON1 activity was greater (P<0.01) for the RR genotype (in Q192R polymorphism) and for the LL genotype (in L55M polymorphism). The frequency of allele R of Q192R polymorphism was significantly higher in obese women (P<0.05) and was associated with an increased risk of obesity (odds ratio=2.0 – 95% confidence interval (1.04; 3.87)).ConclusionL55M and Q192R polymorphisms influence PON1 activity. The allele R of the Q192R polymorphism is associated with an increased risk for development of obesity among Portuguese Caucasian premenopausal women.

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Rezafungin In Vitro Activity against Contemporary Nordic Clinical Candida Isolates and Candida auris Determined by the EUCAST Reference Method

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02438-19 ◽

2020 ◽

Vol 64 (4) ◽

Cited By ~ 3

Author(s):

Marie Helleberg ◽

Karin Meinike Jørgensen ◽

Rasmus Krøger Hare ◽

Raluca Datcu ◽

Anuradha Chowdhary ◽

...

Keyword(s):

Amphotericin B ◽

Target Genes ◽

Specific Activity ◽

Significant Proportion ◽

Reference Method ◽

Cross Resistance ◽

Wild Type ◽

Candida Auris ◽

Content Type

ABSTRACT Rezafungin (formerly CD101) is a novel echinocandin in clinical development. EUCAST epidemiological cutoff values (ECOFFs) have not yet been established. We determined the in vitro activity of rezafungin and comparators against 1,293 Nordic yeast isolates and 122 Indian Candida auris isolates and established single-center wild-type upper limits (WT-UL). The isolates (19 Candida spp. and 13 other yeast species) were identified using Chromagar; matrix-assisted laser desorption ionization–time of flight (MALDI-TOF); and, when needed, internal transcribed spacer sequencing. EUCAST E.Def 7.3.1 susceptibility testing included rezafungin, anidulafungin, micafungin, amphotericin B, and fluconazole. WT-UL were established following EUCAST principles for visual and statistical ECOFF setting. fks target genes were sequenced for rezafungin non-wild-type isolates. EUCAST clinical breakpoints for fungi version 9.0 were adopted for susceptibility classification. Rezafungin had species-specific activity similar to that of anidulafungin and micafungin. On a milligram-per-liter basis, rezafungin was overall less active than anidulafungin and micafungin but equally or more active than fluconazole and amphotericin B against the most common Candida species, except C. parapsilosis. We identified 37 (3.1%) rezafungin non-wild-type isolates of C. albicans (1.9%), C. glabrata (3.0%), C. tropicalis (2.7%), C. dubliniensis (2.9%), C. krusei (1.2%), and C. auris (14.8%). Alterations in Fks hot spots were found in 26/26 Nordic and 8/18 non-wild-type C. auris isolates. Rezafungin displayed broad in vitro activity against Candida spp., including C. auris. Adopting WT-UL established here, few Nordic strains, but a significant proportion of C. auris isolates, had elevated MICs with mutations in fks target genes that conferred echinocandin cross-resistance. fks1 mutations raised rezafungin MICs notably less than anidulafungin and micafungin MICs in C. auris.

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