Adenosine deaminase, dipeptidyl peptidase-IV activities and lipid peroxidation are increased in the saliva of obese young adult

Adenosine deaminase gene variant in diabetes and obesity

Purpose

Personal medicine is a new notion for individualizing treatment in the future. Studying pathogenic markers including genetic variants would be beneficial in better diagnosis and management of complex diseases such as diabetes and obesity. Adenosine deaminase (ADA) is a purine metabolic enzyme and modulates insulin activity in various tissues through several different mechanisms. Increased ADA activity is associated with decreased glucose uptake. A significant increase in serum deaminase activity has been reported in patients with T2DM and obesity. ADA gene polymorphisms seem to affect ADA enzymatic activity and a polymorphism at the position 4223 in the first intron of ADA gene (ADA 4223 A/C) has been previously associated with obesity. The aim of this study was to explore ADA gene 4223 A/C polymorphism and its association with obesity in patients with Type 2 diabetes.

Methods

Obese patients (N = 133: 64 diabetic +69 non-diabetic) with BMI ≥ 30 and subjects with BMI < 30 (N = 152: 83 diabetics +69 non-diabetic) were recruited into a case-control association study. Blood samples were collected and after DNA extraction, the allele and genotype frequency for ADA gene polymorphism was determined using PCR-RFLP technique.

Results

We observed a significant increase for the frequency of AA+CA genotype in non-obese patients with diabetes compared to obese patients with diabetes (P = 0.04, OR = 2.1, 95%CI; 0.93-4.9).

Conclusion

The higher frequency of AA+CA genotype in none obese diabetes individuals and lower frequency of this genotype in obese diabetes subjects indicates an important role for ADA gene polymorphism in diabetes subjects without obesity.

Analytical validation of an automated assay for the measurement of adenosine deaminase (ADA) and its isoenzymes in saliva and a pilot evaluation of their changes in patients with SARS-CoV-2 infection

OBJECTIVES

The aim of the present study was to validate a commercially available automated assay for the measurement of total adenosine deaminase (tADA) and its isoenzymes (ADA1 and ADA2) in saliva in a fast and accurate way, and evaluate the possible changes of these analytes in individuals with SARS-CoV-2 infection.

METHODS

The validation, in addition to the evaluation of precision and accuracy, included the analysis of the effects of the main procedures that are currently being used for SARS-CoV-2 inactivation in saliva and a pilot study to evaluate the possible changes in salivary tADA and isoenzymes in individuals infected with SARS-CoV-2.

RESULTS

The automated assay proved to be accurate and precise, with intra- and inter-assay coefficients of variation below 8.2%, linearity under dilution linear regression with R² close to 1, and recovery percentage between 80 and 120% in all cases. This assay was affected when the sample is treated with heat or SDS for virus inactivation but tolerated Triton X-100 and NP-40. Individuals with SARS-CoV-2 infection (n=71) and who recovered from infection (n=11) had higher mean values of activity of tADA and its isoenzymes than healthy individuals (n=35).

CONCLUSIONS

tADA and its isoenzymes ADA1 and ADA2 can be measured accurately and precisely in saliva samples in a rapid, economical, and reproducible way and can be analyzed after chemical inactivation with Triton X-100 and NP-40. Besides, the changes observed in tADA and isoenzymes in individuals with COVID-19 open the possibility of their potential use as non-invasive biomarkers in this disease.

Characterization of total adenosine deaminase activity (ADA) and its isoenzymes in saliva and serum in health and inflammatory conditions in four different species: an analytical and clinical validation pilot study

Background

Measurement of adenosine deaminase (ADA) can provide information about cell-mediated immunity. This report’s objective was to study the enzymatic activity of total ADA (tADA) and its isoenzymes ADA1 and ADA2 in canine, equine, porcine, and bovine serum and saliva and their changes in different inflammatory situations in each species. Besides, an automated method for ADA2 measurement was developed and validated.

Results

tADA was present in serum and saliva of healthy animals of the four species. Erythro-9-(2-hydroxy-3-nonyl) adenine (EHNA) concentration of 0.47 mM was needed for ADA1 inhibition in canine and porcine samples (serum and saliva) and bovine saliva, whereas for equine saliva 0.94 mM was needed. ADA2 activity was not detected in bovine serum and was very low or absent in equine serum and bovine saliva. An automated procedure to measure ADA2 consisting of adding EHNA to a commercial reagent for tADA measurement provided repetitive (coefficients of variation < 8.8% in serum and < 10% in saliva) and accurate (linearity of serial sample dilutions with R² > 0.90) results, being equivalent to a manual incubation of the sample with EHNA at a similar concentration. Salivary tADA, as well as ADA1 and ADA2, were higher in dogs with leishmaniosis, horses with acute abdominal disease and pigs with lameness than in healthy animals. tADA and isoenzymes in saliva showed a positive significant correlation with serum ferritin in dogs (r = 0.602, P < 0.01; r = 0.555, P < 0.05; and r = 0.632, P < 0.01; respectively for tADA, ADA1 and ADA2) and serum C-reactive protein in pigs (r = 0.700, P < 0.01, for both tADA and ADA1; r = 0.770, P < 0.001, for ADA2), whereas salivary ADA2 significantly correlated with serum amyloid A in horses (r = 0.649, P < 0.01). In cows, salivary tADA and ADA1 significantly increased after calving, correlating with total white blood cell count (r = 0.487, P < 0.05, for both tADA and ADA1).

Conclusions

The activity of total ADA and its different isoenzymes, can be measured in serum and saliva of dogs, horses, pigs and cows by a simple and fast procedure described in this report. When measured in saliva, these analytes correlated with other biomarkers of inflammation and it could potentially be used as a biomarkers of inflammation and immune activation in the species of this study.

The effects of isoflavone supplementation plus combined exercise on salivary markers of oxidative stress in postmenopausal women

This study tested the effect of isoflavone supplementation in addition to combined exercise training in salivary oxidative stress markers in non-obese postmenopausal women. Thirty-two postmenopausal women without hormone therapy were randomly assigned to exercise + placebo (n = 15) or exercise + isoflavone supplementation (n = 17) groups. They performed 30 sessions of combined exercises (aerobic plus resistance) over ten weeks and consumed 100 mg of isoflavone supplementation or placebo. Saliva samples were collected after an overnight fast. Superoxide dismutase, total antioxidant capacity, thiobarbituric acid reactive substances, catalase, total protein and nitrite were determined before and after ten weeks of the intervention. The ANOVA two-way analysis of variance was applied with α of 5%. Both groups increase (p<0.05) superoxide dismutase activity and decrease catalase levels. There was interaction (time × group) in both nitrite and thiobarbituric acid reactive substances results, with increase (p<0.05) in placebo group and decrease (p<0.05) in isoflavone group. No difference was found for total antioxidant capacity or total protein. The combination of isoflavone supplementation and exercise training can promote an antioxidant effect through reduction of lipid peroxidation and concentrations of salivary nitrite.

Adenosine deaminase inhibition

Adenosine deaminase is a critical enzyme in purine metabolism that regulates intra and extracellular adenosine concentrations by converting it to inosine. Adenosine is an important purine that regulates numerous physiological functions by interacting with its receptors. Adenosine and consequently adenosine deaminase can have pro or anti-inflammatory effects on tissues depending on how much time has passed from the start of the injury. In addition, an increase in adenosine deaminase activity has been reported for various diseases and the significant effect of deaminase inhibition on the clinical course of different diseases has been reported. However, the use of inhibitors is limited to only a few medical indications. Data on the increase of adenosine deaminase activity in different diseases and the impact of its inhibition in various cases have been collected and are discussed in this review. Overall, the evidence shows that many studies have been done to introduce inhibitors, however, in vivo studies have been much less than in vitro, and often have not been expanded for clinical use.

Serum activities of dipeptidyl peptidase-4 and adenosine deaminase in polycystic ovary syndrome: association with obesity

Dipeptidyl peptidase-4 (DPP-4) plays a role in metabolic and inflammatory diseases. Increased adenosine deaminase (ADA) has been suggested to induce insulin resistance and inflammation. We measured serum DPP-4 and ADA activities. Serum ADA activity was significantly higher in PCOS group (p = .006), whereas there was no difference in serum DPP-4 activity between the groups (p > .05). When the study subjects were divided into four groups in terms of obesity; an increasing trend in serum ADA activity between the groups was observed and ADA activity was significantly higher in overweight and obese patients with PCOS than nonobese controls (p = .016), there were no significant differences between the other groups (p > .05). A positive correlation was found between ADA and BMI in the whole group (p = .022). Multivariate regression analyses revealed that significant determinants were diastolic blood pressure, ADA, and the presence of PCOS for DPP-4 (R² = 0.344, F = 9.079, p < .001); the presence of PCOS and DPP-4 for ADA (R² = 0.123, F = 6.302, p = .003). We demonstrated increased serum ADA activity as well as its association with obesity in PCOS, while there was no change in serum DPP-4 activity in women with PCOS.

Easy and non-invasive disease detection in pigs by adenosine deaminase activity determinations in saliva

The quantification of adenosine deaminase (ADA) in porcine saliva samples has been analyzed for its use as a marker of disease. First, an analytical validation of the enzymatic assay used for ADA measurements was performed. Afterwards, saliva samples were collected from 50 healthy animals and 64 animals with different symptoms of disease, which were divided into local inflammation, gastrointestinal disorder, respiratory disorder and growth retardation. To optimize ADA measurements, total ADA (tADA), specific ADA (sADA) and ADA isoforms 1 and 2 activities were calculated. Moreover, to preliminarily estimate the diagnostic value of tADA activity measurements for disease detection, receiver operating characteristic (ROC) analyses was performed and compared to the results obtained for salivary acute phase proteins, haptoglobin (Hp) and C-reactive protein (CRP). The salivary levels of tADA activity were significantly elevated in animals with local inflammation, gastrointestinal disorder and respiratory disorder. The calculation of the different ADA activities did not provide additional information to tADA activity quantification for disease detection. The diagnostic value of tADA activity was superior to those observed for Hp and CRP measurements in the present study. It might be concluded that ADA analysis in saliva could be used as a simple, rapid, economic and non-invasive diagnostic tool in porcine production in field conditions.

Evaluation of salivary oxidative parameters in overweight and obese young adults

Background

Obesity is characterized by a deposition of abnormal or excessive fat in adipose tissue, and is linked with a risk of damage to several metabolic and pathological processes associated with oxidative stress. To date, salivary oxidative biomarkers have been minimally explored in obese individuals. Thus, the aim of this study was to assess the concentrations of salivary oxidative biomarkers (ferric-reducing antioxidant power, uric acid, sulfhydryl groups) and lipid peroxidation in obese and overweight young subjects.

Materials and methods

Levels of lipid peroxidation, ferric-reducing antioxidant power, uric acid, and SH groups were determined in the saliva and serum of 149 young adults, including 54 normal weight, 27 overweight, and 68 obese individuals. Anthropometric measurements were also evaluated.

Results

Salivary levels of ferric-reducing antioxidant power, sulfhydryl groups, and lipid peroxidation, as well as serum levels of ferric-reducing antioxidant power, uric acid, and lipid peroxidation were higher in obese patients when compared with individuals with normal weight. There were correlations between salivary and serum ferric-reducing antioxidant power and salivary and serum uric acid in the obese and normal-weight groups.

Conclusions

Our results indicate that the increase in salivary levels of ferric-reducing antioxidant power, sulfhydryl groups, and lipid peroxidation, and serum levels of ferric-reducing antioxidant power, uric acid, and lipid peroxidation could be related to the regulation of various processes in the adipose tissue. These findings may hold promise in identifying new oxidative markers to assist in diagnosing and monitoring overweight and obese patients.