Serum Aspirin Esterase Activity Research Articles

Serum aspirin esterase activity in cord blood and in adults

There is scarce information about altered aspirin – esterase (AE) activities in various physiological and pathological states, as well as the putative agents modulating this activity. Since there are no data on AE levels in cord blood, we set up this study to measure its activity in neonates' cord blood and in adults, using an optimized technique developed in our laboratory. We performed a case-control study with 28 newborns, and control adult subjects were selected from a healthy population of hospital workers. Aspirin esterase activity in cord blood was 60 ± 12 nmol/mL/min vs 87 ± 12 nmol/mL/min in adults, p r = 0.86 p

Serum aspirin esterase activity is lower in end-stage renal disease patients than in healthy control subjects and increases after haemodialysis

Studies regarding aspirin metabolism can be important in patients with renal failure who have an increased risk of cardiovascular diseases. We undertook this study to assess the aspirin esterase (AE) status in end-stage renal disease (ESRD) patients. A total of 42 patients on long-term haemodialysis (HD) with a mean dialysis course of 6.1 y were recruited. Serum AE levels were 44% lower and cholinesterase (ChE) levels were 22% lower in ESRD patients before dialysis as compared with control subjects (P = 0.0001). A very strong correlation was found between AE and ChE levels. AE levels increased on average 28% after dialysis with adjustments for age, gender, total cholesterol, triglyceride and high-density lipoprotein cholesterol (P = 0.002). In addition, ChE levels were significantly increased (48%) after dialysis (P = 0.0001). Changes in AE activity were significantly and positively correlated with those of ChE (r = 0.427, P = 0.005). When we adjusted for several confounders, we found that the changes in AE activity operated by dialysis are significant independently of age, gender, aspirin (ASA) intake, cholesterol, triglycerides, high-density lipoprotein cholesterol and ChE. We report that serum AE activity is significantly lower in ESRD and that treatment by HD results in an increase of activity. We confirm that AE is associated with lipid parameters and ChE. Our results show variations in ASA catabolism between the dialysis sessions, suggesting an oscillating pattern in ASA disposal in these patients. The mechanisms for reduced AE activity in uraemia and the effects of HD need further investigation.

Serum aspirin esterase is strongly associated with glucose and lipids in healthy subjects: different association patterns in subjects with type 2 diabetes mellitus

BackgroundAspirin esterase (AE) activity can account for part of aspirin pharmacokinetics in the circulation, possibly being associated with the impairment of aspirin effectiveness as an inhibitor of platelet aggregation.AimsThe study was aimed at investigating the correlations of serum AE activity with cholinesterase (ChE) and metabolic variables in healthy subjects in comparison to subjects with type 2 diabetes mellitus (T2DM).MethodsIn cardiovascular disease-free T2DM subjects and healthy controls, the AE activity levels and/or the correlation patterns between AE and the other variables were analyzed.ResultsNeither AE nor ChE activities were higher in the subjects with T2DM. Serum AE activity strongly correlated with ChE as well as glucose/lipids variables such as total cholesterol and triglyceride in healthy subjects, while the correlations between AE and glucose/lipids variables were not present in T2DM subjects.ConclusionsThese data may reflect the pathophysiological changes between healthy and T2DM subjects. Our data may thus provide the basis for future studies to unravel the mechanisms.

Serum aspirin esterase activity in cord blood and in adults

AbstractThere is scarce information about altered aspirin – esterase (AE) activities in various physiological and pathological states, as well as the putative agents modulating this activity. Since there are no data on AE levels in cord blood, we set up this study to measure its activity in neonates' cord blood and in adults, using an optimized technique developed in our laboratory. We performed a case-control study with 28 newborns, and control adult subjects were selected from a healthy population of hospital workers. Aspirin esterase activity in cord blood was 60 ± 12 nmol/mL/min vs 87 ± 12 nmol/mL/min in adults, p < 0.00001. No correlation of AE activity and HDL cholesterol, HDL/LDL cholesterol or paraoxonase 1 was found. Aspirin esterase correlated significantly with serum cholinesterase: r = 0.86 p < 0.0001, which was also 30% ower in cord blood than in adults. We show here, for the first time, that cord blood serum has a significant aspirin esterase activity, even though is its 40% lower than that found in adults. Our data provide baseline information for future studies on the physiology of aspirin esterase in children and the factors that modulate its activity to reach adult levels.

Serum cholesterol concentration associated with aspirin esterase activity in older people: preliminary data

Metabolism of aspirin (acetylsalicylic acid), commonly used in older people for the prevention of cardiovascular disease, is important to the effectiveness of this drug. Whereas part of aspirin hydrolysis occurs in blood, there is a paucity of information in regards to circulating aspirin esterase activity in various physiological and pathological conditions. High aspirin esterase activity, corresponding to faster aspirin hydrolysis (thus aspirin non-responsiveness), may occur in cardiovascular disease-prone states. The objective of this study was to investigate the effects of cardio-metabolic variables such as cholesterol on serum aspirin esterase activity in older people who participated in an intervention study on physical activity. A total of 18 non-medicated subjects (7 men/11 women, mean age 67.8 years, body mass index = 23.4 +/- 3.3 kg/m(2)), who completed a 3-month interventional program for a mild-to-moderate increase in physical activity, were analyzed. The body mass index, plasma glucose, serum total cholesterol and aspirin esterase activity were measured in the pre- and post-interventional phases of the study. During the interventional period, the changes in aspirin esterase activity correlated significantly and positively with those of total cholesterol concentrations (r = 0.542, P = 0.020; beta = 0.609, P = 0.035 in a multiple linear regression analysis after adjusting for all the measured variables). The results suggest that cholesterol metabolism alterations may be associated with aspirin metabolism in older people.

Aspirin esterase activity — Evidence for skewed distribution in healthy volunteers

Background Aspirin, with its analgesic, anti-inflammatory, antipyretic, and anti-platelet actions, is one of the most frequently used drugs. Although its use as prophylaxis against thromboembolism is well established, an optimal dose, conferring maximal anti-platelet action without increased risk of bleeding, remains elusive. Method We assessed the possible pharmacokinetic contribution to this problem in 107 healthy, non-medicated volunteers. Serum aspirin esterase activity was evaluated at 37 °C with 1 mM aspirin as substrate. On the basis of the report that most of aspirin esterase activity is accounted for by pseudocholinesterase, we additionally quantified the activity of this enzyme, with and without dibucaine as an inhibitor, using Ellman's reaction, in 41 of our volunteers. Results Aspirin esterase activities in all of our volunteers (33.90 nmol/ml/min to 222.65 nmol/ml/min, median 103.45 nmol/ml/min) showed a continuous and skewed distribution with eight outliers. In the 41 subjects so studied, aspirin esterase activities correlated positively with both pseudocholinesterase activities (Spearman's rho = 0.593, p < 0.001) and dibucaine numbers (Spearman's rho = 0.422, p < 0.01). Conclusions Our results support previous observations that the rate of aspirin hydrolysis is not determined by aspirin esterase alone and that other factors are probably involved. Additionally, the skewed distribution of aspirin esterase activities makes a case for its possible contribution to the phenomenon of aspirin resistance.

Evidence for sex and age difference in human Aspirin metabolism.

Based on reports elucidating sex differences in the prophylactic effects of aspirin against thromboembolism, sex and age differences in the activity of serum aspirin esterase (AE), the enzyme hydrolyzing aspirin, found predominantly in the liver, were measured in healthy persons of various age groups. In randomized healthy subjects, serum AE activity (μg of hydrolysed salicylic acid/30 min/ml) in females (average age 37.4±19.4, n=83) was significantly lower than in males (average age 40.2±18.2, n=81), While serum AE activity in males declined with increasing age, no age differences were found in females. Consequently, while men recorded higher activity than women in the younger age groups, the level of activity in men was lower than women in the older age groups. These sex and age differences in serum AE activity may be responsible in part for the sex differences in the efficacy of aspirin.

Effect of other drugs and chemicals on the degradation of aspirin in vitro: possible extrapolation to in vivo metabolism of aspirin.

To assess the possible influence of other drugs and chemicals on the metabolic degradation of aspirin in man, their effect on the serum aspirin esterase activity was determined in vitro. The activation or inhibition of the enzyme as observed with these compounds suggest the possibility that simultaneous ingestion of these drugs with aspirin may influence the pharmacology and toxicity of the analgesic.

Strain Differences in Aspirin-Induced Gastric Ulceration in Rats

We found that there are strain differences in aspirin-induced ulceration in pylorus-ligated rats; the ulcer indices varied, from high to low, in the following order: Donryu>Sprague-Dawley>Wistar. Several experiments including analysis of gastric contents or ionic flux, determination of serum aspirin esterase activity, absorption of aspirin from the stomach, prothrombin time and hexosamine content in gastric mucosa and juice were performed to elucidate the origin of the differences. A significantly higher acid output in Donryu rats, and higher hexosamine content in the gastric mucosa of Wistar rats were noted. However, it appears unlikely that these factors only contribute to the marked strain difference in aspirin-induced ulcers. The possible different sensitivity of gastric mucosal cell itself to aspirin must be considered.

Serum aspirin esterase activity in women with habitual aspirin intake

A method for the determination of aspirin esterase activity in serum is described. Sera from 59 pregnant women who were habitual aspirin users were found to have a mean enzyme activity value statistically lower than those of 68 non-pregnant women controls or of 12 pregnant women controls who were either occasional users of the drug or were non-users. The distribution of enzyme activity in the experimental group was also significantly different from that of the control group. It is postulated that the low enzyme activity may further aggravate the injurious effects of high intake of aspirin.

Correlation of serum aspirin esterase activity and half-life of salicylic acid.

An inverse correlation was found between the serum aspirin esterase activity in human subjects and the biological half-life of salicylic acid in serum and a direct relationship between the values of the elimination rate constant and the activity of this enzyme. The rate of acetylsalicylic acid breakdown may be one of the factors which influences the biological half-life of salicylates in the organism and may participate also in determining the individual response to the administered drug.