Serum Adenosine Deaminase Activity Research Articles

Relation of elevated serum adenosine deaminase levels to glycated hemoglobin and serum uric acid in type 2 diabetes mellitus

Background: Adenosine deaminase (ADA) is suggested to be an important enzyme for modulating the bioactivity of insulin, but its clinical significance in Type 2 diabetes mellitus is not yet established. The present study was undertaken to evaluate serum ADA activity and serum uric acid levels in patients of Type 2 DM. It is widely reported that immunological imbalance is one of the key factors associated with the metabolic disturbances in type 2 diabetes mellitus. Aims: The present study aimed to evaluate the serum Adenosine Deaminase level and to correlate ADA levels with Blood Glucose and HbA1c levels in Type-2 Diabetes Mellitus patients. Material and Method: It is a case control study. The subjects included in this study were divided into 3 groups. Group I consisted of 50 normal healthy individuals who served as controls with no history of DM. Group II consisted of 50 patients of Type 2 Diabetes Mellitus both males & females in the age group of 40-65 years on oral hypoglycemic drugs with HbA1c 7 %. Serum levels of fasting blood sugar, HbA1c, ADA and uric acid were estimated in all the subjects under study. Results: All the three parameters, FBS, HbA1c, ADA and serum uric acid levels were found to be increased in the patients of Type 2 DM as compared to controls. The mean serum uric acid levels showed a bell shaped relation with glycemic control. Conclusion: From the present study, it is concluded that there is an increase in serum ADA levels with increase in HbA1c levels. It was found that the serum uric acid levels increased with increasing levels of HbA1c 7% (a bell-shaped relation).

Serum adenosine deaminase, catalase, and carbonic anhydrase activities in patients with renal cell carcinoma

Objectives: To determine whether serum levels of adenosine deaminase (AD), catalase (CAT), and carbonic anhydrase (CA) enzymes may be useful biomarkers in the diagnosis of renal tumors and may lead to early diagnosis of renal tumors.Material and methods: The study included 33 patients with renal cell carcinoma (RCC) and 31 healthy controls. The activity of serum AD, CA, and CAT was determined and analyzed using the Giusti spectrophotometric method, H2O2 substrate, and C02 hydration, respectively.Results: Serum AD and CA activity were significantly higher in patients with RCC than in controls. However, serum CAT activity was significantly lower in patients with RCC than in controls.Conclusion: These markers might be potentially important as an additional biochemical tool for diagnosing RCC. We believe multidisciplinary studies are needed to plan patients’ preoperative and postoperative treatment and to create follow-up protocols.

Platelet aggregation and serum adenosine deaminase (ADA) activity in pregnancy associated with diabetes, hypertension and HIV.

Platelet aggregation and adenosine deaminase (ADA) activity were evaluated in pregnant women living with some disease conditions including hypertension, diabetes mellitus and human immunodeficiency virus infection. The subject population is consisted of 15 non-pregnant healthy women [control group (CG)], 15 women with normal pregnancy (NP), 7 women with hypertensive pregnancy (HP), 10 women with gestational diabetes mellitus (GDM) and 12 women with human immunodeficiency virus-infected pregnancy (HIP) groups. The aggregation of platelets was checked using an optical aggregometer, and serum ADA activity was determined using the colorimetric method. After the addition of 5 µM of agonist adenosine diphosphate, the percentage of platelet aggregation was significantly (p < 0·05) increased in NP, HP, GDM and HIP groups when compared with the CG, while the addition of 10 µM of the same agonist caused significant (p < 0·05) elevations in HP, GDM and HIP groups when compared with CG. Furthermore, ADA activity was significantly (p < 0·05) enhanced in NP, HP, GDM and HIP groups when compared with CG. In this study, the increased platelet aggregation and ADA activity in pregnancy and pregnancy-associated diseases suggest that platelet aggregation and ADA activity could serve as peripheral markers for the development of effective therapy in the maintenance of homeostasis and some inflammatory process in these pathophysiological conditions. Copyright © 2016 John Wiley & Sons, Ltd.

Elevated Serum ADA Activity as a Marker for Diagnosis and Prognosis of Visceral Leishmaniasis and Post Kala-Azar Dermal Leishmaniasis in Indian Patients

Serum adenosine deaminase (ADA) activity increases in diseases where cellular immunity is involved. Since cell-mediated immune responses play a paramount role in the pathogenesis and healing of the visceral leishmaniasis, therefore, the present study was undertaken to evaluate the serum ADA activity in different pathological conditions. Adenosine deaminase was determined in sera of active visceral leishmaniasis (VL) patients (n = 39), active postkala-azar dermal leishmaniasis (PKDL) cases (n = 34) at the point of diagnosis and after treatment stages along with healthy controls (n = 30), endemic healthy subjects (n = 34) and endemic asymptomatic subjects (n = 34).Our in-vitro result revealed that monocytes secrete significant ADA level in response to Leishmania donovani (L.donovani) stimulation. The serum ADA activity in active VL and PKDL subjects were found to be significantly higher than that of respective treated cases and healthy controls. We also observed a marginal number (17.6%) of endemic asymptomatic subjects showed elevated serum ADA activity. Further, the ADA activity in PKDL was found to be decreased gradually during the different phases of treatment. Interestingly, 2 out of 32 treated VL cases found to have high serum ADA activity during follow up period were relapsed within few days. These results suggest the possibility of ADA as a marker of clinical pathogenesis and can be used as a surrogate marker in the diagnosis and prognosis of VL and PKDL.

Ectonucleotidases and adenosine deaminase activity in laying hens naturally infected by Salmonella Gallinarum and their effects on the pathogenesis of the disease

Salmonella Gallinarum is the etiologic agent of fowl typhoid that affects chickens and turkeys causing egg production drops, infertility, lower hatchability, high mortality, and as a consequence severe economic losses to the poultry industry. The alterations in NTPDase and adenosine deaminase (ADA) activities have been demonstrated in several inflammatory conditions; however, there are no data in the literature associated with this infection. Thus, the aim of this study was to evaluate the activities of NTPDase, 5′nucleotidase, and ADA in serum and hepatic tissue of laying hens naturally infected by Salmonella Gallinarum. Liver and serum samples were collected of 27 laying hens (20 S. Gallinarum infected and 7 uninfected). NTPDase and 5′-nucleotidase activities in serum were increased (P < 0.001) in infected animals to hydrolysis of substrate ATP, ADP and AMP. In addition, it was observed decreased (P < 0.001) in ADA activity in serum of laying hens naturally infected by S. Gallinarum; as well as increased (P < 0.001) ADA activity in liver tissue of infected laying hens. Histopathological analyses revealed that S. Gallinarum caused fibrinoid necrosis in liver and spleen associated with infiltrates of heterophils, macrophages, lymphocytes, and plasma cells. Considering that NTPDase and ADA are involved in the cell-mediated immunity, this study suggests that activities of these enzymes could be important biomarkers to determine the severity of inflammatory and immune responses in salmonellosis, contributing to clarify the pathogenesis of the disease.

Correlation of serum Adenosine deaminase activity (ADA) with fasting blood sugar levels in Type II Saudi Diabetic Patients.

Aim: This study aims to correlate the association of serum Adenosine deaminase activity (ADA) with fasting blood sugar (FBS) levels. Patients and Methods: Serum FBS levels and serum ADA activity were measured in 71 Type 2 diabetes mellitus (DM) patients and 24 controls. Results: Serum ADA activity and FBS levels were elevated in type 2 DM group in comparison to control group significantly (p

Alterations in lipid peroxidation and T-cell function in women with hyperemesis gravidarum

The objective of this study was to investigate serum adenosine deaminase (ADA) activity as a marker of T lymphocyte activation and parameters of oxidative stress and antioxidant defence in hyperemesis gravidarum (HG). Serum ADA activity, malondialdehyde (MDA), catalase (CAT) and glutathione peroxidase (GPx) levels were investigated in 40 pregnant women with the HG and 40 with healthy pregnancies, in a descriptive study. Although serum ADA and CAT were measured to be higher in HG group, the difference was not significant. Serum MDA and GPx levels were significantly elevated in women with HG when compared with those without HG. The significance of changes in lipid peroxidation and T-cell activation in the pathogenesis of HG and whether this is a cause or a compensatory reaction to HG requires further investigations with larger multicentre trials.

Study on Changes in Serum Adenosine Deaminase Activity in Patients with Hepatitis

Study on Changes in Serum Adenosine Deaminase Activity in Patients with Hepatitis

Syzygium cumini seed extract ameliorates adenosine deaminase activity and biochemical parameters but does not alter insulin sensitivity and pancreas architecture in a short-term model of diabetes.

The effects of the aqueous seed extract of Syzygium cumini (ASc) in a short-term model of diabetes in rats are little explored. The present study was designed to evaluate the effect of the ASc on adenosine deaminase (ADA) activity and on biochemical and histopathological parameters in diabetic rats. ASc (100 mg/kg) was administered for 21 days in control and streptozotocin (STZ)-induced (60 mg/kg) diabetic rats. ADA activity, lipoperoxidation (cerebral cortex, kidney, liver and pancreas) and biochemical (serum) and histopathological (pancreas) parameters were evaluated. The main findings in this short-term model of Diabetes mellitus (DM) were that the ASc (i) significantly reverted the increase of ADA activity in serum and kidney; (ii) ameliorated the lipoperoxidation in the cerebral cortex and pancreas of the diabetic group; (iii) demonstrated hypolipidemic and hypoglycemic properties and recovered the liver glycogen; and iv) prevented the HOMA-IR index increase in the diabetic group. Therefore, the ASc can be a positive factor for increasing the availability of substrates with significant protective actions, such as adenosine. Moreover, by maintaining glycogen and HOMA-IR levels, the extract could modulate the hyperglycemic state through the direct peripheral glucose uptake. Our data revealed that the short-term treatment with ASc has an important protective role under pathophysiological conditions caused by the early stage of DM. These results enhance our understanding of the effect of the ASc on the purinergic system in DM.

Diagnostic Value of Serum Adenosine Deaminase (ADA) Level for Pulmonary Tuberculosis.

Background:Diagnosis of tuberculosis (TB) is not always easy, thus employing methods with a short duration and acceptable sensitivity and specificity is necessary to diagnose TB.Objectives:The aim of this study was to investigate the diagnostic value of serum adenosine deaminase (ADA) level for diagnosis of pulmonary tuberculosis.Patients and Methods:A total of 160 sex and age-matched subjects were included in this study, and were divided to four groups; forty patients with pulmonary tuberculosis (PTB) diagnosed based on the national TB program (NTP), forty patients with non-tuberculosis bacterial pneumonia, forty patients with lung cancer and forty people who were healthy in every respect. Serum adenosine deaminase activity in patients of each group was measured by the Giusti and Galanti calorimetry method using a commercial kit (Diazyme, USA). The ANOVA analysis was used to compare groups for quantitative variables.Results:Mean serum ADA level in the PTB group was clearly higher than the mean serum ADA in the other three groups. Mean serum ADA was 26 IU/L in PTB patients, 19.48 IU/L in patients with pneumonia, 15.8 IU/L in patients with lung cancer, and 10.7 IU/L in the control group (P < 0.05). In regard to the cut off value of 26 IU/L for ADA in patients with PTB sensitivity and specificity was defined as 35% and 91%, respectively.Conclusions:Serum ADA activity with high specificity percentage may be a useful alternative test in restricted resource areas to rule out diagnosis of PTB. However, serum ADA activity is not a useful tool for TB diagnosis.

Serum Adenosine Deaminase (ADA) Activity: A Novel Screening Test to Differentiate HIV Monoinfection From HIV-HBV and HIV-HCV Coinfections.

CD4(+) cell count, the common HIV infection screening test, is costly and unable to differentiate HIV monoinfection from its concurrent infection with hepatitis B or C virus. We aimed to ascertain diagnostic value of serum adenosine deaminase (ADA) activity as a useful tool to differentiate HIV mono- and co-infection. Blood samples were collected from 30 HIV-HBV and 30 HIV-HCV coinfected patients, 33 HIV positive subjects, and 72 controls. CD4(+) cell count, serum total ADA (tADA), and ADA1, and ADA2 isoenzyme activities were determined and their sensitivity and specificity were computed. tADA and ADA2 activities were significantly higher and CD4(+) counts were markedly lower in all patients compared with controls. Strong inverse agreements between CD4(+) cell counts and both tADA and ADA2 activities were observed. Serum tADA and ADA1 activities showed the highest specificity and the highest sensitivity, respectively, for differentiating HIV monoinfection from HIV-HBV and HIV-HCV coinfections. We showed strong agreement and correlation between CD4(+) cell count and ADA enzyme activity. Based on high ADA sensitivity and specificity, it is concluded that determination of ADA activity might be a novel diagnostic tool to distinguish of HIV monoinfection from its coinfection with HBV or HCV.

No association between serum adenosine deaminase activity and disease activity in Crohn's disease.

Adenosine deaminase activity is proposed as a marker of inflammation in some inflammatory conditions. To investigate the association of serum adenosine deaminase activity and disease activity in Crohn's disease patients. In a cross-sectional study, 30 consecutive known cases of Crohn's disease (15 with active disease and 15 in remission) referring to a university hospital in Tehran (Iran) and 15 age- and gender-matched healthy controls were studied. Disease activity was assessed using the Crohn's disease activity index (cutoff >150). Total serum adenosine deaminase activity, C-reactive protein, erythrocyte sedimentation rate, and fecal calprotectin were evaluated in patients. Serum adenosine deaminase activity was measured in controls. Mean age of the patients was 36.8 ± 12.6 years, and 56.7 % were male. Serum adenosine deaminase activity in patients with active disease, patients in remission, and controls was 12.3 ± 5.9, 14.6 ± 6.2, and 11.9 ± 6.4 U/L, respectively (P = 0.458). Compared with patients in remission, those with active disease had higher erythrocyte sedimentation rate (40.4 ± 30.6 vs. 16.9 ± 16.0 mm/h, P = 0.014) and higher frequency of positive C-reactive protein (66.6 vs. 13.3 %, P = 0.004) and positive fecal calprotectin tests (86.6 vs. 33.3 %, P = 0.004). Serum adenosine deaminase activity was not correlated with erythrocyte sedimentation rate (r = 0.05, P = 0.761) and was not different between patients with positive and negative C-reactive protein (12.2 ± 5.4 vs. 14.2 ± 6.5 U/L, P = 0.393) and fecal calprotectin tests (11.7 ± 5.3 vs. 16.0 ± 6.5 U/L, P = 0.063). In patients with Crohn's disease, serum adenosine deaminase activity is not associated with clinical disease activity or with other inflammation markers and cannot be suggested as an inflammation marker.

Serum adenosine deaminase activity in thyroid disorders

Context: It has been widely reported that thyroid gland is very much prone to autoimmune disorder. Adenosine deaminase (ADA), an enzyme distributed in the human tissues, is considered as nonspecific marker of cell-mediated immunity. Also it is suggested to be an important enzyme for modulating the bioactivity of thyroid hormones, but its clinical significance in thyroid disorders is not yet characterized. Therefore this study aims to see association between serum ADA and different thyroid disorders if any. Research Design and Methods: This was a hospital based cross sectional study conducted in Immunoassay laboratory of Department of Biochemistry, BPKIHS. A total of 122 subjects were selected and divided into five groups: Group 1 (Euthyroid), Group 2 (Overt Hyperthyroid), Group 3 (Subclinical Hyperthyroid), Group 4 (Overt Hypothyroid) and Group 5 (Subclinical Hypothyroid) based on the thyroid function status. Samples were stored at − 20 o till the assay of parameters. Thyroid hormones; thyroxine (fT4), triiodothyronine (fT3) and thyroid stimulating hormones (TSH) were assayed by Enzyme Linked Immunoflouresent Assay (ELFA) technique. Serum ADA activity was estimated by spectrophotometric methods of Giusti and Galanti. Data are presented as mean ± SD. Statistical analysis done by Chi-square test and one way ANOVA. P <0.05 considered as significant. Result: Out of 122 subjects 91 were female and 31 were male, showing the female preponderance of thyroid disorders. There was significant difference in ADA activity in different thyroid disorders (P < 0.001). Conclusion: The females were more prone to thyroid disorders and there was significant difference in ADA activity in different thyroid disorders. Our findings suggest that ADA may play a role in the pathophysiology of thyroid disorders, however a large scale study is required to predict the relationship.

Serum Adenosine Deaminase as Inflammatory Marker in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a prototypical inflammatory joint disease. The degree of inflammation is reflected in the extent of joint damage, which further has influence on the quality of life of patients with RA, including risk of atherosclerosis. Hence, besides clinical indices, estimation of degree of inflammation using biochemical markers helps in effecting optimum treatment strategies. C-reactive protein (CRP) is established as an inflammatory marker in patients with RA. Adenosine deaminase (ADA), an enzyme of purine metabolism is considered as a marker of cell mediated immunity and has also been suggested as a marker of inflammatory process in RA. The present study attempts to study the efficacy of serum ADA activity as an inflammatory marker in RA. Forty six RA patients and forty six age and sex matched healthy controls were included in the study. ADA activity and high sensitivity C-reactive protein (hsCRP) levels in serum were measured in all the subjects. Statistical analyses were done using Medcalc statistical software version 12.2.2. ADA activity and hsCRP levels were increased in RA patients compared to controls (p<0.0001 and 0.0001 respectively). Significant positive correlation was obtained between hsCRP and ADA in patients (r=0.316, p=0.033). Receiver operating characteristic (ROC) curve analysis revealed statistically significant area under curve (AUC) for ADA that is comparable to that obtained for hsCRP (0.776, p<0.0001 for ADA, 0.726, p<0.0001 for hsCRP). Similar diagnostic utility was obtained with ROC generated cut-off value of 25.3 IU/L (82.6% sensitivity and 65.2% specificity) and with control mean value of 23.48 IU/L (86.96% sensitivity and 54.35% specificity) for ADA. Findings of the present study indicate the importance of ADA as a marker of inflammation. Considering the higher sensitivity obtained, we propose control mean (23.48 IU/L) as a cut-off for serum ADA activity as an inflammatory marker. Owing to the simplicity and also the cost effectiveness of ADA assay, ADA may be recommended as a marker of inflammation in patients with RA. However, further larger and well controlled studies are needed to establish its role as inflammatory marker.

Influence of hemodialysis on the plasma concentration of adenosine deaminase in patients with chronic kidney disease

Introduction: Over the past years there has been a significant increase in hospitalizations and treatments due to kidney complications that eventually resulted in the increased number of patients on dialysis. The adenosine deaminase (ADA) enzyme mediates the formation of some defense cells of the organism and is therefore a marker of inflammation. Objective: The objective of this study was to evaluate biomarkers of renal function and serum ADA of hemodialysis patients. Materials and methods: Blood samples were collected from 80 patients – 40 women and 40 men – between 19 and 60 years old, before and after the completion of hemodialysis. Results: There was a significant difference in levels of creatinine, urea and ADA in pre- and post-hemodialysis periods (p < 0.0001). There was a significant increase in post-dialysis ADA regardless of sex; however there was a significantly greater increase in men. Conclusion: The results showed a reduction in urea and creatinine parameters, evidencing the main purpose of hemodialysis. This study suggests that the determination of ADA activity could be used to monitor inflammation in hemodialysis patients, however wider and more specific studies are needed to show the effectiveness of serum ADA activity as an inflammatory marker in patients with chronic kidney disease.

Deficits in endogenous adenosine formation by ecto-5'-nucleotidase/CD73 impair neuromuscular transmission and immune competence in experimental autoimmune myasthenia gravis.

AMP dephosphorylation via ecto-5′-nucleotidase/CD73 is the rate limiting step to generate extracellular adenosine (ADO) from released adenine nucleotides. ADO, via A2A receptors (A2ARs), is a potent modulator of neuromuscular and immunological responses. The pivotal role of ecto-5′-nucleotidase/CD73, in controlling extracellular ADO formation, prompted us to investigate its role in a rat model of experimental autoimmune myasthenia gravis (EAMG). Results show that CD4+CD25+FoxP3+ regulatory T cells express lower amounts of ecto-5′-nucleotidase/CD73 as compared to controls. Reduction of endogenous ADO formation might explain why proliferation of CD4+ T cells failed upon blocking A2A receptors activation with ZM241385 or adenosine deaminase in EAMG animals. Deficits in ADO also contribute to neuromuscular transmission failure in EAMG rats. Rehabilitation of A2AR-mediated immune suppression and facilitation of transmitter release were observed by incubating the cells with the nucleoside precursor, AMP. These findings, together with the characteristic increase in serum adenosine deaminase activity of MG patients, strengthen our hypothesis that the adenosinergic pathway may be dysfunctional in EAMG. Given that endogenous ADO formation is balanced by ecto-5′-nucleotidase/CD73 activity and that A2ARs exert a dual role to restore use-dependent neurocompetence and immune suppression in myasthenics, we hypothesize that stimulation of the two mechanisms may have therapeutic potential in MG.

Dietary Modulation of Thymic Enzymes

Malnutrition is a complex syndrome caused by an inadequate intake of energy, protein, minerals and vitamins which affects the immune system. Nutritional imbalances, present in children with energy-protein malnutrition and infections, make defining the specific effects of each of them on the thymus difficult. For this reason, it is necessary to design an experimental model in animals that could define a single variable. As the thymus atrophy described in humans is similar to that observed in murines, a rat experimental model makes the extrapolation to man possible. Some authors suggest that the activity of Adenosine Deaminase (ADA) and Purine Nucleoside Phosphorylase (PNP)--involved in purine metabolism--have an influence on T lymphocyte development and the immune system, due to intracellular accumulation of toxic levels of deoxynucleotides. Studies in our group, performed in an experimental model on Wistar growing rats, have demonstrated that protein deficiency or imbalance in the profile of essential amino acids in the diet, produce loss of thymus weight, reduction in the number of thymocytes, a diminished proportion of T cells presenting the W3/13 antigenic determinant and DNA content with concomitant increase in cell size, and the proportion of immature T cells and activity of ADA and PNP, without modifying the activity of 5´Nucleotidase in the thymus. It is important to point out that there were neither differences in energy intake between experimental groups and their controls, nor clinical symptoms of deficiency of other nutrients. The increase in these thymic enzyme activities was an alternative mechanism to avoid the accumulation of high levels of deoxynucleotides, which would be toxic for T lymphocytes. On the other hand, the administration of a recovery diet, with a high amount of high quality protein, was able to reverse the mentioned effects. The quick reply of Adenosine Deaminase to nutritional disorders and the following nutritional recovery, points out to this determination as a potential functional marker of nutritional status. Some authors have demonstrated an increase in ADA activity, in serum and other biological fluids in patients with various diseases involving defense mechanisms. According to these findings, it could be inferred that ADA activity in serum would follow the same behavior as observed in a rat thymus. So, we have analyzed if its determination could be considered a functional biochemical parameter in populations at nutritional risk. We analyzed the serum ADA activity in groups of individuals with altered nutritional status evaluated through different markers--young adult patients with Nervous Anorexia, overweight or obese school children, children suffering cystic fibrosis. The results show a statistically significant increase in the ADA activity in all groups, with respect to their healthy controls--same age range and socio economic status. The results obtained to date suggest the importance of including the determination of serum Adenosine Deaminase activity in the biochemical evaluation of the nutritional status, as a functional marker related to defense mechanisms.

Malignant ovine theileriosis: serum concentrations of some inflammatory components and adenosine deaminase activity

Theileria lestoquardi (hirci) is a tick-transmitted protozoan parasite that causes a malignant disease in sheep. The parasite invades ovine leukocytes and stimulates a variety of immune responses in the host. In order to evaluate serum adenosine deaminase activity and the status of some inflam- matory mediators, 34 fat-tailed Iranian sheep naturally infect- ed with T. lestoquardi were selected and divided into three subgroups according to their parasitemia rates ( 4 %). Fifteen non-infected sheep were sampled as controls. Blood samples were taken from jugular vein into EDTA- containing tubes for measuring haematological parameters and without anticoagulant for serum concentrations of inflam- matory cytokines (IL-1β, IL-6, IFN-γ and TNF-α) and aden- osine deaminase (ADA) activity. Remarkable decreases were seen in haematological parameters including red blood cells (RBCs), packed cell volume (PCV) and haemoglobin in in- fected sheep. In contrast, serum levels of the measured cyto- kines and also ADA activity were significantly increased in infected animals. However, with increase in the parasitemia rate, no significant increase or decrease was observed in the levels of cytokines and ADA activity. The results showed that the infection with T. lestoquardi promotes significant changes in major inflammatory components in infected sheep. These remarkable alterations could be triggered from earlier stage of infection.

Serum Adenosine Deaminase Activity and Neopterin Levels during Therapy in Patients with Pulmonary Tuberculosis and Community-Acquired Pneumonia

Serum Adenosine Deaminase Activity and Neopterin Levels during Therapy in Patients with Pulmonary Tuberculosis and Community-Acquired Pneumonia

Alterations of ectonucleotidases and acetylcholinesterase activities in lymphocytes of Down syndrome subjects: Relation with inflammatory parameters

BackgroundSubjects with Down syndrome (DS) have an increased susceptibility to infections and autoimmune disorders. ATP, adenosine, and acetylcholine contribute to the immune response regulation, and NTPDase, adenosine deaminase (ADA) and acetylcholinesterase (AChE) are important enzymes in the control of the extracellular levels of these molecules. We evaluated the activities of these enzymes and the cytokine levels in samples of DS individuals. MethodsThe population consisted of 23 subjects with DS and 23 healthy subjects. Twelve milliliters of blood was obtained from each subject and used for lymphocyte and serum preparation. Lymphocytes were separated on Ficoll density gradients. After isolation, NTPDase and AChE activities were determined. ResultsThe NTPDase activity using ADP as substrate was increased in lymphocytes of DS patients compared to control (P<0.05); however, no alterations were observed in the ATP hydrolysis. An increase was observed in the AChE activity in lymphocytes and in ADA activity in serum of DS patients when compared to healthy subjects (P<0.05). In DS subjects, an increase in the levels of IL-1β, IL-6, TNF-α and IFN-γ and a decrease in the IL-10 levels were also observed (P<0.05). ConclusionsAlterations in the NTPDase, ADA and AChE activities as well changes in the cytokine levels may contribute to immunological alterations observed in DS.