Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rats were subjected to physical exercise in the form of a single race in a treadmill. Unexercised animals and those immediately or 1 h after the exercise were given oil or oily solution of parathion-methyl in a dose of 10 mg/kg by stomach gauge. At 1 h after pesticide administration the activity of cholinesterase (ChE) was determined in the serum, of paraoxonase--in the serum and liver, and that of beta-glucuronidase (beta-gluc)--in the serum, liver and intestine. Single physical exercise increased ChE activity in the serum, inhibited paraoxonase activity in the serum and liver; on the other hand, it did not affect significantly beta-gluc activity in the serum, but inhibited that enzyme in a transient manner in the liver and activated it in the intestine. In acute poisoning with parathion-methyl it was observed that ChE and paraoxonase activities were inhibited, while beta-gluc activity was enhanced in the serum. Single physical exercise either diminished or had no effect on enzymatic changes observed in acute poisoning with parathion-methyl.
 ...
PMID:Parathion-methyl effect on the activity of hydrolytic enzymes after single physical exercise in rats. 300 31

Parathion-methyl, 10 mg/kg p.o., was given to unexercised rats, rats trained for 3 weeks and resting for 2 days, and trained rats subjected to a single physical exercise before treatment. The activity of cholinesterase (ChE) in the serum, of paraoxonase--in the serum and liver, and of beta-glucuronidase (beta-gluc)--in the serum, liver and intestine were determined 1 h after the treatment. Repeated physical exercise increased beta-gluc activity in the serum and liver and inhibited it in the intestine, while a single race after repeated exercise inhibited paraoxonase activity in the serum. Parathion-methyl inhibited ChE and paraoxonase activities and an increased beta-gluc activity in the serum. Repeated physical exercise and a single race, applied 2 days after the end of training, affects the activity of parathion-methyl in a significant yet diversified manner, dependent upon the examined biochemical parameters.
 ...
PMID:The effect of chronic physical exercise on the activity of hydrolytic enzymes in acute poisoning with parathion-methyl in rats. 300 32

Zenarestat, (3-(4-bromo-2-fluorobenzyl)-7-chloro-2,4-dioxo-1,2,3,4- tetrahydroquinazolin-1-yl) acetic acid, an aldose reductase inhibitor is metabolized mainly to the glucuronide in rat and man. The glucuronide was purified from urine of volunteers after ingestion of zenarestat. The structure of the glucuronide was confirmed by LC-MS and NMR as 1-O-acyl-beta-glucuronide. This compound was unstable at physiological pH, being converted to its structural isomers and the aglycone with half-life of 25 min at pH 7.4 and 37 degrees C in aqueous solution. Enzymatic hydrolysis of the glucuronide was studied in urine, blood and tissues. beta-Glucuronidase in human urine contributed little to the hydrolysis of the glucuronide, while in rat urine at pH 6, it was degraded by beta-glucuronidase and the formation of zenarestat was clearly faster than its formation in buffer at pH 6. In both rat and human blood, these reactions were accelerated by albumin, although rat red blood cells may also contribute. The rate of degradation was not affected by red blood cell membrane, haemoglobin, globulin, esterases or beta-glucuronidase. Arylesterase in rat liver, arylesterase and acetylcholinesterase in the kidney, and beta-glucuronidase in both tissues may contribute. Thus, enzymatic degradation of zenarestat 1-O-acyl-beta-glucuronide is dependent not only on pH and temperature but also on species and the type of tissue or body fluid.
 ...
PMID:Enzymatic hydrolysis of zenarestat 1-O-acylglucuronide. 802 35

Egasyn is an accessory protein of beta-glucuronidase (beta-G) in the liver microsomes. Liver microsomal beta-G is stabilized within the luminal site of the microsomal vesicles by complexation with egasyn which is one of the carboxylesterase isozymes. We investigated the effects of organophosphorus compounds (OPs) such as insecticides on the dissociation of egasyn-beta-glucuronidase (EG) complex. The EG complex was easily dissociated by administration of OPs, i.e. fenitrothion, EPN, phenthionate, and bis-beta-nitrophenyl phosphate (BNPP), and resulting beta-G dissociated was released into blood, leading to the rapid and transient increase of plasma beta-G level with a concomitant decrease of liver microsomal beta-G level. In a case of phenthionate treatment, less increase in plasma beta-G level was observed, as compared with those of other OPs. This may be explained by the fact that phenthionate was easily hydrolyzed by carboxylesterase. Similarly, carbamate insecticides such as carbaryl caused rapid increase of plasma beta-G level. In contrast, no significant increase of plasma beta-G level was observed when pyrethroid insecticides were administered to rats. This is due to the fact that pyrethroids such as phenthrin and allethrin were easily hydrolyzed by A-esterase as well as carboxylesterase. On the other hand, addition of OPs to the incubation mixture containing liver microsomes caused the release of beta-G from microsomes to the medium. From these in vivo and in vitro data, it is concluded that increase of the plasma beta-G level after OP administration is much more sensitive biomarker than cholinesterase inhibition to acute intoxication of OPs and carbamates.
 ...
PMID:Toxicological significance in the cleavage of esterase-beta-glucuronidase complex in liver microsomes by organophosphorus compounds. 1042 85

Previous reports in animals considered beta-glucuronidase activity as a novel biomarker of anticholinesterase (organophosphates and carbamates) pesticides exposure. Acid phosphatase activity was also shown to increase after organophosphates exposure. In addition, there is evidence that the paraoxonase status influences sensitivity to specific pesticides. In this study, activities of beta-glucuronidase, acid phosphatase, cholinesterase, and paraoxonase were measured in plasma from plastic greenhouse workers exposed over the long term to different pesticides, including organophosphates and carbamates, in order to evaluate the potential chronic toxicity of pesticides at occupational level. Our results show that activities of paraoxonase and cholinesterase were decreased in applicators of pesticides compared to non-applicators. Likewise, it was found that activities of beta-glucuronidase and acid phosphatase were associated with pesticide exposure in humans, and that both biochemical parameters were related to each other. Interestingly, the paraoxonase B allele (phenotyped in plasma) was associated with a higher risk of inhibition of cholinesterase activity above a 25% level, which supports the hypothesis that paraoxonase phenotypes are associated with susceptibility of humans to anticholinesterase pesticides toxicity.
 ...
PMID:Effect of long-term exposure to pesticides on plasma esterases from plastic greenhouse workers. 1520 26