Metabolism and Tissue Distribution of Chelerythrine and Effects of Macleaya Cordata Extracts on Liver NAD(P)H Quinone Oxidoreductase

Background:Macleaya cordata (Willd.) (Papaveraceae) is listed as a feed additive in animal production by the European Food Authority.Methods: The metabolites of chelerythrine in rats were measured in vitro and in vivo by rapid and accurate high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/QqTOF-MS). The structures of CHE metabolites were elucidated by comparing their changes in accurate molecular masses and fragment ions with those of parent ion or metabolite. The metabolic enzymes that were involved in chelerythrine reduction were investigated using an inhibition method. The tissue distribution of chelerythrine and the effects on NQO1 following intragastric administration with M. cordata extracts in rats were examined.Results: A total of twelve metabolites of chelerythrine were characterized by this approach in rat liver S9 and in vivo. The reduction of the iminium bond of chelerythrine and subsequent O-demethylation was the main metabolic pathway of chelerythrine in rat liver S9 while the reduction of the iminium bond of chelerythrine was the main metabolic pathway of chelerythrine in rats in vivo. After the rats were given intragastric administration, the low concentration residues of sanguinarine and chelerythrine in different rat tissues were found at 48 h after the last dose, suggesting that both compounds could be widely distributed in tissues. The results also indicated that XO, NQO1, NQO2, and carbonyl reductase are involved in chelerythrine reduction. Macleaya cordata extracts treated female and male rats, respectively, showed different responses, inhibiting NQO1 activity in males, but inducing NQO1 activity in females. Chelerythrine had a weak impact on NQO1 activity, but sanguinarine inhibited NQO1 activityConclusion: Through studying the effects of cytosolic reductase inhibitors on chelerythrine reduction and the impact of chelerythrine and sanguinarine on the activity of NQO1 in vitro and in vivo, we clarified the potential drug interaction of Macleaya cordata extract in clinical application, so as to provide theoretical guidance for clinically safe medication. In addition, it provided a reference basis for the metabolic mechanism of chelerythrinein rats.

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The Impact of Carboxylesterases in Drug Metabolism and Pharmacokinetics

Current Drug Metabolism ◽

10.2174/1389200219666180821094502 ◽

2019 ◽

Vol 20 (2) ◽

pp. 91-102 ◽

Cited By ~ 22

Author(s):

Li Di

Keyword(s):

Tissue Distribution ◽

Critical Role ◽

Individual Variability ◽

Human Pharmacokinetics ◽

Metabolizing Enzymes ◽

Soft Drugs ◽

Hydrolysis Of Esters ◽

The Impact

Background:Carboxylesterases (CES) play a critical role in catalyzing hydrolysis of esters, amides, carbamates and thioesters, as well as bioconverting prodrugs and soft drugs. The unique tissue distribution of CES enzymes provides great opportunities to design prodrugs or soft drugs for tissue targeting. Marked species differences in CES tissue distribution and catalytic activity are particularly challenging in human translation.Methods:Review and summarization of CES fundamentals and applications in drug discovery and development.Results:Human CES1 is one of the most highly expressed drug metabolizing enzymes in the liver, while human intestine only expresses CES2. CES enzymes have moderate to high inter-individual variability and exhibit low to no expression in the fetus, but increase substantially during the first few months of life. The CES genes are highly polymorphic and some CES genetic variants show significant influence on metabolism and clinical outcome of certain drugs. Monkeys appear to be more predictive of human pharmacokinetics for CES substrates than other species. Low risk of clinical drug-drug interaction is anticipated for CES, although they should not be overlooked, particularly interaction with alcohols. CES enzymes are moderately inducible through a number of transcription factors and can be repressed by inflammatory cytokines.Conclusion:Although significant advances have been made in our understanding of CESs, in vitro - in vivo extrapolation of clearance is still in its infancy and further exploration is needed. In vitro and in vivo tools are continuously being developed to characterize CES substrates and inhibitors.

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Testosterone augments endotoxin-mediated cerebrovascular inflammation in male rats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00465.2005 ◽

2005 ◽

Vol 289 (5) ◽

pp. H1843-H1850 ◽

Cited By ~ 38

Author(s):

Ali Razmara ◽

Diana N. Krause ◽

Sue P. Duckles

Keyword(s):

Blood Vessels ◽

In Vitro Models ◽

Male Rats ◽

Cerebral Blood Vessels ◽

Treatment Groups ◽

Protein Levels ◽

Cox 2 ◽

The Impact

Activation of inflammatory mechanisms contributes to cerebrovascular pathophysiology. Male gender is associated with increased stroke risk, yet little is known about the effects of testosterone in the cerebral circulation. Therefore, we explored the impact of testosterone treatment on cerebrovascular inflammation with both in vivo and in vitro models of inflammation. We hypothesized that testosterone would augment the expression of two vascular markers of cellular inflammation, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Using four groups of male rats [intact, orchiectomized (ORX), and ORX treated with either testosterone (ORXT) or the testosterone metabolite 17β-estradiol (ORXE)], we determined effects of the sex hormones on cerebrovascular inflammation after intraperitoneal LPS injection. Western blot analysis showed that induction of inflammatory markers was increased in cerebral blood vessels from ORXT rats compared with intact or ORX rats. In contrast, in cerebral blood vessels from ORXE rats, there was a significant decrease in endotoxin-induced COX-2 and iNOS protein levels. Confocal microscopy of cerebral blood vessels from ORXT rats showed increased COX-2 and iNOS immunoreactivity in both endothelial and smooth muscle cells after LPS treatment. In vitro incubation with LPS also induced COX-2 in pial vessels isolated from the four animal treatment groups, with the greatest induction observed in ORXT vessels compared with the ORX and ORXE groups. Production of PGE2, a principal COX-2-derived prostaglandin end product, was also greatest in cerebral vessels isolated from ORXT rats. In conclusion, testosterone increases cerebrovascular inflammation; this effect may contribute to stroke differences between men and women.

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Selective role of neuropeptide Y receptor subtype Y2 in the control of gonadotropin secretion in the rat

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00274.2007 ◽

2007 ◽

Vol 293 (5) ◽

pp. E1385-E1392 ◽

Cited By ~ 16

Author(s):

L. Pinilla ◽

R. Fernández-Fernández ◽

J. Roa ◽

J. M. Castellano ◽

M. Tena-Sempere ◽

...

Keyword(s):

Neuropeptide Y ◽

Male Rats ◽

Receptor Subtype ◽

Central Administration ◽

Adult Rats ◽

Gonadotropin Secretion ◽

Gonadotropic Axis ◽

The Impact

Different signals with key roles in energy homeostasis regulate the reproductive axis. These include neuropeptide Y and polypeptide YY3-36, whose type Y2 receptor is the most abundant of this family in the brain. We evaluated herein the putative roles of Y2 receptors in the control of gonadotropin secretion by means of central administration of PYY13-36 (agonist of Y2 receptors) and BIIE 0246 (antagonist of Y2 receptors) to intact and orchidectomized male rats. In addition, the ability of PYY13-36 to elicit GnRH and gonadotropin secretion in vitro and the impact of fasting on LH responses to PYY13-36 in vivo were also monitored. Central administration of PYY13-36 significantly decreased the circulating levels of both gonadotropins, an effect that was observed in prepubertal and adult rats. Yet a dual action of Y2 receptors in the control of male gonadotropic axis was evidenced as their activation induced 1) stimulation of gonadotropin responses to GnRH at the pituitary but 2) inhibition of GnRH secretion at the hypothalamus. Antagonization of Y2 receptors failed to modify basal LH secretion in intact males either after being fed ad libitum or after being fasted. In contrast, their central blockade in orchidectomized rats evoked a significant increase in circulating LH and FSH level, suggesting the constitutive activation of Y2 receptor in such stimulated conditions. In summary, our data evidence a complex mode of action of Y2 receptors in the control of gonadotropic axis, with stimulatory and inhibitory actions at different levels of the system that are sensitive to the gonadal status.

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Effects of acute hepatic ischemia on the electrophoretic patterns of the polypeptides and phosphopolypeptides of the microsomal membrane fraction of rat liver

Canadian Journal of Biochemistry ◽

10.1139/o80-141 ◽

1980 ◽

Vol 58 (10) ◽

pp. 1039-1050 ◽

Cited By ~ 3

Author(s):

Monique Behar-Bannelier ◽

Les Pinteric ◽

Robert K. Murray

Keyword(s):

Rat Liver ◽

Membrane Fraction ◽

Sodium Dodecyl ◽

Microsomal Membrane ◽

Male Rats ◽

Base Line ◽

Hepatic Ischemia ◽

Electrophoretic Patterns

The purpose of this study was to establish when alterations of the electrophoretic patterns of the polypeptides and phosphopolypeptides of the microsomal membrane fraction of the livers of rats become observable after initiation of acute hepatic ischemia. Ischemia was initiated by clamping the vascular supply to the left and median lobes of the livers of adult male rats. The animals were killed at various times thereafter (up to 6 h, and in certain instances, 24 h) and microsomal membrane fractions were prepared from each. The patterns of the polypeptides and phosphopolypeptides of these fractions were analysed by sodium dodecyl sulfate – polyacrylamide gel electrophoresis, using staining with Coomassie blue to analyse the polypeptides and radioautography to analyse 32P-labelled phosphopolypeptides. Alterations of the polypeptide pattern were apparent in the fractions from animals killed at 4 h and after; prior to this time point, subtle alterations, at most, could be distinguished. Effects of acute ischemia on the pattern of phosphopolypeptides of the microsomal membrane fraction were studied after phosphorylation in vivo (produced by intraperitoneal injection of [32P]phosphoric acid) and in vitro (using [γ-32P]ATP as phosphate donor). No marked changes in the phosphopolypeptide pattern produced by phosphorylation in vivo were observed until 6 h after clamping, by which time a diminution of the radioactivity in the majority of the phosphopolypeptides was evident. However, noteworthy alterations of the pattern of phosphopolypeptides produced by phosphorylation in vitro were observable in the membrane fractions from animals subjected to 2 h of ischemia. Overall the study provides a base line delineating the time sequence during which alterations of the electrophoretic patterns of the polypeptides and phosphopolypeptides of rat liver microsomal membranes become evident following the onset of acute hepatic ischemia and reveals that gross alterations of the polypeptide patterns of these membranes and of certain other subcellular fractions are not an early occurrence following this severe type of injury. The possible utility of the application of phosphorylation in vitro for detecting early alterations in membrane structure following cell injury is suggested.

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Glucocorticoid–dependent maintenance of CYP2C11–dependent oxidation in male rat liver in vivo

Human & Experimental Toxicology ◽

10.1191/096032700678815648 ◽

2000 ◽

Vol 19 (2) ◽

pp. 126-131 ◽

Cited By ~ 4

Author(s):

M Murray

Keyword(s):

Rat Liver ◽

Male Rats ◽

Male Rat ◽

Hormonal Factors ◽

Adrenal Hormones ◽

Male Specific ◽

Physiological Correlate ◽

Made In

1 Hormonal factors participate in the regulation of xenobiotic metabolising enzymes in liver. Hepatic xenobiotic oxidation capacity is decreased in adrena-lectomised rats, which directly implicates adrenal hormones in the control of cytochrome P450 (CYP) expression. In addition, recent studies in cultured hepatocytes have demonstrated that low concentra-tions of glucocorticoid upregulate the male-specific CYP2C11, which is a major enzyme that catalyses xenobiotic and steroid hydroxylations in rat liver. The present study evaluated whether glucocorticoid or mineralocorticoid may be the adrenal factor that contributes to the in vivo expression of CYP2C11 in liver. 2 Adrenalectomy of male rats selectively decreased CYP2C11-dependent 2a-/16a-hydroxylation of testos-terone and other steroid substrates to 60-70% of control, whereas activities mediated by other constitu-tive CYPs were unaffected. The decrease in CYP2C11 activity was due to impaired protein expression in liver after adrenalectomy. Administration of dexametha-sone (DEX; 0.2 mg/kg i.p. daily for 6 days) restored CYP2C11 activity and protein, whereas the mineralo-corticoid deoxycorticosterone (DOC) and adrenocorti-cotropic hormone (ACTH) were ineffective. 3 These findings establish that glucocorticoids have a partial role in the maintenance of CYP2C11 expression and associated microsomal oxidation in liver and provide a physiological correlate for similar observa-tions made in vitro in hepatocyte culture.

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In vitro and in vivo suppression of growth of rat liver epithelial tumor cells by antisense oligonucleotide against protein kinase C-alpha

Journal of Hepatology ◽

10.1034/j.1600-0641.2000.033004601.x ◽

2000 ◽

Vol 33 (4) ◽

pp. 601-608 ◽

Cited By ~ 8

Author(s):

Shwu-Bin Lin ◽

Li-Ching Wu ◽

Siao-Ling Huang ◽

Hui-Lun Hsu ◽

Sung-Hwa Hsieh ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Tumor Cells ◽

Rat Liver ◽

Antisense Oligonucleotide ◽

Epithelial Tumor ◽

Kinase C ◽

Epithelial Tumor Cells

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Identification of genes early responsive to gamma-irradiation in isolated rat hepatocytes in vitro and rat liver in vivo by cDNA array gene expression analysis

Zeitschrift für Gastroenterologie ◽

10.1055/s-2005-920060 ◽

2005 ◽

Vol 43 (05) ◽

Author(s):

DS Batusic ◽

H Christiansen ◽

B Saile ◽

RM Hermann ◽

J Dudas ◽

...

Keyword(s):

Gene Expression ◽

Gamma Irradiation ◽

Rat Liver ◽

Gene Expression Analysis ◽

Cdna Array ◽

Rat Hepatocytes ◽

Isolated Rat Hepatocytes ◽

Isolated Rat

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Effect of X-irradiation on gene expression of rat liver chemokines: in vivo and in vitro studies

Zeitschrift für Gastroenterologie ◽

10.1055/s-2008-1037499 ◽

2008 ◽

Vol 46 (01) ◽

Cited By ~ 1

Author(s):

F Moriconi ◽

H Christiansen ◽

N Sheikh ◽

J Dudas ◽

...

Keyword(s):

Gene Expression ◽

Rat Liver ◽

In Vitro Studies ◽

X Irradiation

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Hepato- and Nephroprotective Effects of the Polyphenol Concentrate From Cabernet Sauvignon Grape Varieties Cultivated in Kazakhstan in the Experimental Model Of CCL4-Induced Toxicity

INTERNATIONAL JOURNAL OF TOXICOLOGICAL AND PHARMACOLOGICAL RESEARCH ◽

10.25258/ijtpr.v9i03.9068 ◽

2017 ◽

Vol 9 (03) ◽

Author(s):

Nurgozhin T. ◽

Sergazy S. H. ◽

Adilgozhina G. ◽

Gulyayev A. ◽

Shulgau Z. ◽

...

Keyword(s):

Carbon Tetrachloride ◽

Experimental Model ◽

Lethal Dose ◽

Radical Scavenging ◽

Cabernet Sauvignon ◽

Intragastric Administration ◽

Liver And Kidney ◽

Antioxidant Stress

Objective:This study investigates the hepatoprotective effect and the antioxidant role of polyphenol concentrate in the experimental model of carbon tetrachloride (CCl4) induced toxicity. Methods: Antioxidant activity of Cabernet Sauvignon grape polyphenol were evaluated by radical scavenging of 1,1-diphenyl-2-picryl hydrazyl radical (DPPH), 2,2’-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS.+). In addition, the effects of polyphenol concentrate on the survival of Wistar rats in the toxicity model, was also investigated. The polyphenol concentrate was administered for 5 five days prior to injection of carbon tetrachloride in a sub-lethal dose of 300 mg/kg of animal body weight in order to perform histological examinations of the liver and kidney, and detect the levels of AST, ALT and bilirubin. Results: Administration of polyphenol concentrate increased animal survival in the experimental model. Moreover, the intragastric administration of polyphenol concentrate prior to the initiation of the experimental model of toxicity, which was caused by a sub-lethal CCl4 dose, reduced morphological injuries in the liver and kidney, decreased the AST and ALT levels of the blood serum. Discussion and conclusion: Our data demonstrate that polyphenol concentrate possesses an antioxidant potential both in vitro and in vivo by reducing antioxidant stress that was caused by CCl4 administration into rats.

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