Cu2+-dependent stereoselective hydrolysis of a chiral organophosphonothioate insecticide for domestic mammals' sera and its albumins.

Acute toxicity of organophosphate (OPs) pesticides is a public health problem. The adverse effects are associated with the inhibition and aging of nervous system B-esterases such as acetyl cholinesterase (AChE) and neuropathic target esterase (NTE). Treatment based on A-esterases such as mammal serum paraoxonase-1 has been suggested. This ex vivo study shows the Cu2+-dependent hydrolysis of trichloronate (TCN), a racemic organophosphonothioate insecticide, in human and domestic mammal serum (dog, goat, pig, sheep and cow). Ca2+-dependent (2.5 mM) or EDTA-resistant (5 mM) activity (1-6%) was not significant (p>0.05) in all samples, except goat serum and its albumin, which showed higher levels of TCN hydrolysis (38-58%) than other mammals with 100 and 300 µM copper sulfate at physiological conditions for 60 min. Goat serum albumin (GSA) showed significant (p˂0.05) stereoselective hydrolysis (+)-TCN ˃ (-)-TCN (45% versus 33%). This suggests that GSA is the protein responsible for Cu2+-dependent TCNase activity in goat serum. This is the first report on Cu2+-dependent A-esterase activity in mammalian tissues. This goat serum cuproprotein could be considered as an alternative in future biotechnological applications including enantiomeric synthesis, bioremediation and antidotal treatment of organophosphonothioate pesticide poisoning.

Calcific Aortic Valve Stenosis and Atherosclerotic Calcification.

PURPOSE OF REVIEW: This review summarizes the pathophysiology of calcific aortic valve stenosis (CAVS) and surveys relevant clinical data and basic research that explain how CAVS arises. RECENT FINDINGS: Lipoprotein(a) [Lp(a)], lipoprotein-associated phospholipase A2 (Lp-PLA2), oxidized phospholipids (OxPL), autotaxin, and genetic driving forces such as mutations in LPA gene and NOTCH gene seem to play a major role in the development of CAVS. These factors might well become targets of medical therapy in the coming years. CVAS seems to be a multifactorial disease that has much in common with coronary artery disease, mainly regarding lipidic accumulation and calcium deposition. No clinical trials conducted to date have managed to answer the key question of whether Lp(a) lowering and anti-calcific therapies confer a benefit in terms of reducing incidence or progression of CAVS, although additional outcome trials are ongoing.

Ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities in prostate cancer patients: influence of Gleason score, treatment and bone metastasis.

The relation between adenine nucleotides and cancer has already been described in literature. Considering that the enzymes ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) act together to control nucleotide levels, we aimed to investigate the role of these enzymes in prostate cancer (PCa). E-NPP and ADA activities were determined in serum and platelets of PCa patients and controls. We also verified the influence of the Gleason score, bone metastasis and treatment in the enzyme activities. Platelets and serum E-NPP activity increased, whereas ADA activity in serum decreased in PCa patients. In addition, Gleason score, metastasis and treatment influenced E-NPP and ADA activities. We may propose that E-NPP and ADA are involved in the development of PCa. Moreover, E-NPP and ADA activities are modified in PCa patients with distinct Gleason score, with bone metastasis, as well as in patients under treatment.

Enzymes that hydrolyze adenine nucleotides in platelets and polymorphisms in the alpha2 gene of integrin alpha2beta1 in patients with von Willebrand disease.

Von Willebrand disease (VWD) is one of the most common inherited bleeding diseases caused by a qualitative or quantitative deficiency of the von Willebrand factor (FvW). FvW is a multimeric glycoprotein synthesized by megakaryocytes and endothelial cells and it is present in the subendothelial matrix, blood plasma, platelets, and endothelium. This glycoprotein plays an important role in thrombus formation by initiating platelet adhesion to sites of injury as well as platelet aggregation. The aim of this study was to evaluate the activities of enzymes that hydrolyze adenine nucleotides in platelets, ristocetin-induced platelet aggregation (RIPA), and polymorphisms of the alpha2 gene of alpha2beta1 integrin from VWD patients. Platelet nucleoside triphosphate diphosphohydrolase (NTPDase), 5'-nucleotidase, and ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP) activities were verified in 14 VWD patients. For RIPA determination, a final concentration of 1.25 mg/ml of ristocetin was used. Polymorphisms of the alpha2 gene were analyzed through PCR. Platelet NTPDase and E-NPP were decreased in VWD patients. 5'-Nucleotidase activity was not statistically significant between controls and VWD patients. RIPA was significantly reduced, with an allelic frequency of 78.57% for 807C in VWD patients. Our results indicated reduced platelet NTPDase and E-NPP activities which might be related to the low platelet adhesiveness. The prevalence of the 807C allele might account for the variability in bleeding in VWD.

Ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities in patients with uterine cervix neoplasia.

OBJECTIVE: Ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities, in the platelets and serum, were examined in patients with uterine cervix neoplasia without treatment as well as in patients treated by conization or radiotherapy (RTX). DESIGN AND METHODS: The patients were divided based on the amount of time from the end of the treatments until the day of the blood sampling. Groups I (n=19) (conization) and III (n=11) (radiotherapy) (treated from one to five years earlier), groups II (n=19) (conization) and IV (n=16) (radiotherapy) (treated recently; up to three months earlier) and the non-treated group (cancer) (n=7). RESULTS: E-NPP and ADA in the platelets and E-NPP in the serum were decreased in all the treated groups in relation to the control and non-treated groups, while ADA in the serum was decreased only in the conization groups in relation to them. In group II, E-NPP and ADA, in the platelets, were increased in relation to group IV. CONCLUSION: The tendency of reduction for E-NPP and ADA indicates that they may act together to control nucleotide levels and it may also be speculated that surgery causes greater platelet activation contributing to the changes seen in the conization groups. In this sense, platelets seem to be more sensitive than serum.