Disease relevance of Retinoyl beta-glucuronide

• Milligram doses of [3H]lithocholate glucuronide resulted in partial or complete cholestasis [1].
• 3 alpha, 17 beta-androstanediol glucuronide in plasma. A marker of androgen action in idiopathic hirsutism [2].
• Because the biliary excretion is a major elimination pathway for CPT-11 and its metabolites [an active metabolite, 7-ethyl-10-hydroxy-camptothecin (SN-38), and its glucuronide, SN38-Glu], several hypotheses for the toxicity involve biliary excretion [3].
• It is suggested that glucuronosyl transferase activity may occur widely in colorectal cancer cells and could contribute to resistance to drugs that are susceptible to inactivation by glucuronide conjugation [4].
• Our results show that the targeted-beta-glucuronidase activation of BHAMG can increase the specificity of chemotherapy for rat hepatoma in vitro and suggest that the targeted activation of glucuronide prodrugs may be useful for cancer therapy [5].

Psychiatry related information on Retinoyl beta-glucuronide

• Role of morphine glucuronide metabolites in morphine dependence in the rat [6].
• Clinical symptoms possibly related to the psychic state (mood alteration) or associated to sympathetic changes (anxiety, motor activity) respectively altered sulfate or glucuronide excretion [7].
• Water deprivation also led to a significant reduction in the renal clearance of paracetamol accompanied by an increase in the renal clearance of the glucuronide [8].
• CONCLUSION:: Determination of 5-hydroxytryptophol glucuronide by ELISA offers promising results in detection of previous alcohol consumption [9].
• A time study with tissue slices showed similarities between the in vitro pattern of glucuronide synthesis and the excretion pattern of these compounds seen in earlier in vivo studies [10].

High impact information on Retinoyl beta-glucuronide

• During the enzymatic hydrolysis, a benzo[a]pyrene derivative is formed which binds to DNA to a far greater extent than either the 3-hydroxybenzo[a]pyrene or its glucuronide [11].
• Evidence that supports that assumption was obtained by comparing the randomization of 14C in the urinary glucuronide with that in glucose in blood from the hepatic vein of four of the subjects before and after they were given glucagon [12].
• It is metabolized in humans to a reactive, unstable acyl glucuronide which accumulates in plasma [13].
• The human uridine 5'-diphosphate-glucuronosyltransferase 2B4 (UGT2B4) converts hydrophobic bile acids into more hydrophilic glucuronide derivatives [14].
• Since both drugs are eliminated exclusively after conjugation as glucuronide, this study demonstrates a relative sparing of this pathway of biotransformation of drugs in subjects receiving cimetidine [15].

Chemical compound and disease context of Retinoyl beta-glucuronide

• We have found that mycophenolic acid is also converted to its glucuronide by several lines of human colorectal carcinoma cells, including HT29, Lovo, and Colo-205 [4].
• The kinetics and urinary excretion of etoposide and etoposide glucuronide were determined in 11 patients with obstructive jaundice (bilirubin greater than 2.0 mg/dL) and in 23 patients with normal renal and hepatic function [16].
• 17 beta-estradiol glucuronide: an inducer of cholestasis and a physiological substrate for the multidrug resistance transporter [17].
• One potential method to overcome the cardiac toxicity of Dox is to apply a nontoxic, glucuronide prodrug (HMR 1826) from which Dox is released by the action of beta-glucuronidase, an enzyme present at high levels in many tumors [18].
• Role of breast cancer resistance protein (Bcrp1/Abcg2) in the extrusion of glucuronide and sulfate conjugates from enterocytes to intestinal lumen [19].

Biological context of Retinoyl beta-glucuronide

• Plasma pharmacokinetics of total and ultrafiltrable platinum, irinotecan, SN-38, and its glucuronide, SN-38G, were determined [20].
• A major metabolite was formed by hydroxylation of IQ at the 5-position; it was present in urine and bile and was conjugated as the glucuronide or sulfate ester, which together accounted for about 40% of urinary or biliary metabolites [21].
• The clearance of etoposide and formation of etoposide glucuronide have been measured in an isolated, perfused rat liver model to evaluate the effect of impaired hepatic function on etoposide kinetics [22].
• Based on enhanced formation of sulfate but not glucuronide conjugates in homogenates of human liver treated with inhibitors of the hydrolases, it is suggested that futile cycling is more pertinent to the regulation of sulfation than glucuronidation [23].
• After overnight fasting, enrichment of glucuronide position 5 relative to body water (G5/body water) was significantly higher in type 1 diabetic patients compared with control subjects, indicating a reduced contribution of glycogenolysis to glucose production (38 +/- 3 vs. 46 +/- 2%) [24].

Anatomical context of Retinoyl beta-glucuronide

• Further studies are needed to clarify the biological importance of the glucuronide of the base FUra which accumulates intracellularly as the concentration of FUra increases within the hepatocytes [25].
• Both the untransformed and transformed epidermal cell lines converted [3H]B(a)P to water-soluble metabolites, primarily glucuronide conjugates [26].
• In contrast to the primary cells, a major pathway of trans-7,8-dihydro-7,8-dihydroxybenzo(a)pyrene metabolism in the untransformed and transformed cell lines was a glucuronide conjugate [26].
• The glucuronidation of the individual isomers was stereoselective, as dog hepatic microsomes glucuronidated the S-isomer but failed to generate a glucuronide conjugate of the R-isomer [27].
• The initial velocity of bilirubin glucuronide formation in rat liver microsomes, measured by radiochemical assay, was considerably more rapid than for bilirubin in liposomes of egg phosphatidylcholine (p less than 0.001) [28].

Associations of Retinoyl beta-glucuronide with other chemical compounds

• Bilirubin glucuronide rearrangement in vitro was accompanied by nonenzymic hydrolysis [29].
• The active substance in urine was isolated, subjected to high-performance liquid chromatographic (HPLC) analysis, and found to be a glucuronide conjugate of a known DCF metabolite, 4'-hydroxydiclofenac (4'-OH DCF) [30].
• We report that a cholestatic estrogen metabolite, 17 beta-estradiol glucuronide (E217G), is a substrate for the MDR transporter, P-glycoprotein [17].
• The effect of sodium taurocholate on the biliary export of stable mutagenic phenolic glucuronide metabolites of benzo(a)pyrene from livers of corn oil- or 3-methylcholanthrene-treated rats was studied using a nonrecirculating perfusion system [31].
• The ABCG2-mediated transport of [3H]E1S was potently inhibited by SN-38 and many sulfate conjugates but not by glucuronide and glutathione conjugates or other anionic compounds [32].

Gene context of Retinoyl beta-glucuronide

• In addition, in contrast to wild-type MRP1, leukotriene C(4) transport by the W1246C-MRP1 protein was no longer inhibitable by E(2)17betaG, indicating that the mutant protein had lost the ability to bind the glucuronide [33].
• Considering the role of UGT1A9 in catecholestrogen metabolism, PPAR alpha and PPAR gamma activation may contribute to the protection against genotoxic catecholestrogens by stimulating their inactivation in glucuronide derivatives [34].
• Furthermore, sulphated bile salts were high-affinity competitive inhibitors of etoposide glucuronide transport by MRP3 (IC50 approximately 10 microM) [35].
• The ratios of leukotriene C4 transport and bilirubin glucuronide transport, determined in the same membrane vesicle preparation, indicated substrate specificity differences between MRP1 and MRP2 with a preference of MRP2 for the glucuronides [36].
• In summary, our data showed that several members of UGT1A and UGT2B families are capable of converting LA and AA metabolites into glucuronide derivatives, which is considered an irreversible step to inactivation and elimination of endogenous substances from the body [37].

Analytical, diagnostic and therapeutic context of Retinoyl beta-glucuronide

• Pharmacokinetics of irinotecan and SN-38 and its glucuronide were determined using high-performance liquid chromatography and noncompartmental modeling [38].
• The steady-state removal rate of 4MUS and formation rates of 4MU and its glucuronide conjugate (4MUG) were not altered with perfusion flow direction, suggesting the presence of even or parallel distributions of 4MUS desulfation and 4MU glucuronidation activities [39].
• Several lines of evidence based on both ex vivo and in vitro results indicate that the approach described using a glucuronide prodrug may be useful in facilitating more selective delivery of chemotherapy to tumors in humans [18].
• The amount of LTB4 glucuronide (16.7-29.4 pmol/ml) and 20-carboxy-LTB4 (18.9-30.6 pmol/ml) present in the urine of subjects injected with LTB4 was determined using an isotope dilution mass spectrometric assay before and after treatment of the urine samples with beta-glucuronidase [40].
• Cell preparations were incubated with 1- 14C-naphthol over 1 hour and the glucuronide and sulphate conjugates formed were separated by thin-layer chromatography [41].

References