Effects of different bile salts on steady-state mRNA levels and transcriptional activity of cholesterol 7α-hydroxylase

Hepatology ◽  
1994 ◽  
Vol 19 (4) ◽  
pp. 941-947 ◽  
Author(s):  
William M. Pandak ◽  
Z. Reno Vlahcevic ◽  
Douglas M. Heuman ◽  
Kaye S. Redford ◽  
John Y. L. Chiang ◽  
...  
Keyword(s):  
Steady State ◽  
Bile Salts ◽  
Transcriptional Activity ◽  
Mrna Levels

scholarly journals Hormonal regulation of cholesterol 7alpha-hydroxylase specific activity, mRNA levels, and transcriptional activity in vivo in the rat

1997 ◽  
Vol 38 (12) ◽  
pp. 2483-2491 ◽  
Author(s):  
W M Pandak ◽  
D M Heuman ◽  
K Redford ◽  
R T Stravitz ◽  
J Y Chiang ◽  
...  
Keyword(s):  
Hormonal Regulation ◽  
Transcriptional Activity ◽  
Specific Activity ◽  
Mrna Levels

scholarly journals Isolation, Identification and Function of Pichia anomala AR2016 and Its Effects on the Growth and Health of Weaned Pigs

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1179
Author(s):  
Yajun Ma ◽  
Zhihong Sun ◽  
Yan Zeng ◽  
Ping Hu ◽  
Weizhong Sun ◽  
...  
Keyword(s):  
Oral Administration ◽  
Relative Abundance ◽  
Bile Salts ◽  
Average Daily Gain ◽  
Pichia Anomala ◽  
Simulated Gastric Fluid ◽  
Transferase Activity ◽  
Mrna Levels ◽  
Weaned Pigs ◽  
Intestinal Juice

This study isolates and identifies Pichia anomala (P. anomala) AR2016, and studies its effect on the growth and health of weaned pigs. A P. anomala strain from solid wine koji is isolated and identified using 26S rDNA analysis, and its culture conditions are optimized. Heat tolerance, bile salt tolerance, artificial gastric, and intestinal juice tolerance are evaluated. In our methodology, thirty 28 d Large White × Landrace × Rongchang weaned pigs were randomly divided into three groups with 10 barrows in each, and fed a maize-soybean meal diet and orally administered 0.85% saline (CK), 1 mL 1 × 109 cfu/mL Candida utilis (C. utilis), and 1 mL 1 × 109 cfu/mL P. anomala once daily for 28 days. A P. anomala strain was identified and named P. anomala AR2016. P. anomala AR2016 grew best in yeast extract peptone dextrose medium with pH 5.0 at 28 °C, 180 r/min and could tolerate 45 °C for 0.5 h, 0.2% pig bile salts, simulated gastric fluid, and 1.0% simulated intestinal fluid. Our results show that compared with the CK group, orally administered P. anomala AR2016 increases average daily gain, the ileal villus height, the ileal mucosal concentrations of occludin and zonula occluens-1, the serum glucose and total protein concentration, total superoxide dismutase, glutathione peroxidase, and total antioxidative capacity activity, the trypsin and lipase activity in jejunal and ileal contents, the jejunal and ileal mucosa mRNA levels of ALP, TNF-α, and TLR-2, and the relative abundance of Bacteroidetes, Actinobacteria, Succinivibrionaceae, Lachnospiraceae, and Prevotellaceae (p < 0.05). Compared with the CK group, oral administration of P. anomala AR2016 decreased the incidence of diarrhea, aspartate aminotransferase activity, alanine amino-transferase-activity, malondialdehyde, D-lactic acid and endotoxin content in serum, the mRNA level of aminopeptidase N of ileum mucosa, and the relative abundance of Proteobacteria, Clostridiaceae, Campylobacteraceae, Vibrionaceae, Bacillus, and Pseudon (p < 0.05). Collectively, the study indicates that P. anomala AR2016 can tolerate high acidity and high bile salts, and has high survivability in the artificial gastric intestinal juice environment. Oral administration of P. anomala AR2016 improves the growth performance, reduces the incidence of diarrhea, enhances intestinal barrier function, and improves microflora in weaned pigs.

scholarly journals Genomic structure of murine methylmalonyl-CoA mutase: evidence for genetic and epigenetic mechanisms determining enzyme activity

1993 ◽  
Vol 296 (3) ◽  
pp. 663-670 ◽  
Author(s):  
M F Wilkemeyer ◽  
E R Andrews ◽  
F D Ledley
Keyword(s):  
Enzyme Activity ◽  
Steady State ◽  
Transcription Initiation ◽  
Cultured Cells ◽  
Genomic Structure ◽  
Genetic Regulation ◽  
Regulatory Elements ◽  
Transcription Unit ◽  
Mrna Levels ◽  
Sequence Motifs

Methylmalonyl-CoA mutase (MCM) is a nuclear-encoded mitochondrial matrix enzyme. We have reported characterization of murine MCM and cloning of a murine MCM cDNA and now describe the murine Mut locus, its promoter and evidence for tissue-specific variation in MCM mRNA, enzyme and holo-enzyme levels. The Mut locus spans 30 kb and contains 13 exons constituting a unique transcription unit. A B1 repeat element was found in the 3′ untranslated region (exon 13). The transcription initiation site was identified and upstream sequences were shown to direct expression of a reporter gene in cultured cells. The promoter contains sequence motifs characteristic of: (1) TATA-less housekeeping promoters; (2) enhancer elements purportedly involved in co-ordinating expression of nuclear-encoded mitochondrial proteins; and (3) regulatory elements including CCAAT boxes, cyclic AMP-response elements and potential AP-2-binding sites. Northern blots demonstrate a greater than 10-fold variation in steady-state mRNA levels, which correlate with tissue levels of enzyme activity. However, the ratio of holoenzyme to total enzyme varies among different tissues, and there is no correlation between steady-state mRNA levels and holoenzyme activity. These results suggest that, although there may be regulation of MCM activity at the level of mRNA, the significance of genetic regulation is unclear owning to the presence of epigenetic regulation of holoenzyme formation.

scholarly journals Regulation of mdr2 P-glycoprotein expression by bile salts

1997 ◽  
Vol 321 (2) ◽  
pp. 389-395 ◽  
Author(s):  
Charles M. G. FRIJTERS ◽  
Roelof OTTENHOFF ◽  
Michel J. A. van WIJLAND ◽  
Carin M. J. van NIEUWKERK ◽  
Albert K. GROEN ◽  
...  
Keyword(s):  
Bile Salt ◽  
Bile Salts ◽  
Control Diet ◽  
Mrna Level ◽  
Northern Blotting ◽  
Mrna Levels ◽  
Male Mice ◽  
Complete Replacement ◽  
P Glycoprotein ◽  
Mrna Content

The phosphatidyl translocating activity of the mdr2 P-glycoprotein (Pgp) in the canalicular membrane of the mouse hepatocyte is a rate-controlling step in the biliary secretion of phospholipid. Since bile salts also regulate the secretion of biliary lipids, we investigated the influence of the type of bile salt in the circulation on mdr2 Pgp expression and activity. Male mice were fed a purified diet to which either 0.1% (w/w) cholate or 0.5% (w/w) ursodeoxycholate was added. This led to a near-complete replacement of the endogenous bile salt pool (mainly tauromuricholate) by taurocholate or tauroursodeoxycholate respectively. The phospholipid secretion capacity was then determined by infusion of increasing amounts of tauroursodeoxycholate. Cholate feeding resulted in a 55% increase in maximal phospholipid secretion compared with that in mice on the control diet. Northern blotting revealed that cholate feeding increased mdr2 Pgp mRNA levels by 42%. Feeding with ursodeoxycholate did not influence the maximum rate of phospholipid output or the mdr2 mRNA content. Female mice had a higher basal mdr2 Pgp mRNA level than male mice, and this was also correlated with a higher phospholipid secretion capacity. This could be explained by the 4-fold higher basal cholate content in the bile of female compared with male mice. Our results suggest that the type of bile salts in the circulation influences the expression of the mdr2 gene.

Influence of environmental enrichment on steady-state mRNA levels for EAAC1, AMPA1 and NMDA2A receptor subunits in rat hippocampus

2007 ◽  
Vol 1174 ◽  
pp. 18-27 ◽  
Author(s):  
Josefine Andin ◽  
Martin Hallbeck ◽  
Abdul H. Mohammed ◽  
Jan Marcusson
Keyword(s):  
Steady State ◽  
Environmental Enrichment ◽  
Rat Hippocampus ◽  
Mrna Levels

Quantitative assessment of ground squirrel mRNA levels in multiple stages of hibernation

2002 ◽  
Vol 10 (2) ◽  
pp. 93-102 ◽  
Author(s):  
L. Elaine Epperson ◽  
Sandra L. Martin
Keyword(s):  
Steady State ◽  
Core Body Temperature ◽  
Ground Squirrels ◽  
Apolipoprotein A1 ◽  
Mrna Levels ◽  
Cdna Subtraction ◽  
Global Issues ◽  
Α2 Macroglobulin ◽  
Steady State Levels ◽  
Molecular Components

Hibernators in torpor dramatically reduce their metabolic, respiratory, and heart rates and core body temperature. These extreme physiological conditions are frequently and rapidly reversed during the winter hibernation season via endogenous mechanisms. This phenotype must derive from regulated expression of the hibernator’s genome; to identify its molecular components, a cDNA subtraction was used to enrich for seasonally upregulated mRNAs in liver of golden-mantled ground squirrels. The relative steady-state levels for seven mRNAs identified by this screen, plus five others, were measured and analyzed for seasonal and stage-specific differences using kinetic RT-PCR. Four mRNAs show seasonal upregulation in which all five winter stages differ significantly from and are higher than summer (α2-macroglobulin, apolipoprotein A1, cathepsin H, and thyroxine-binding globulin). One of these mRNAs, α2-macroglobulin, varies during the winter stages with significantly lower levels at late torpor. None of the 12 mRNAs increased during torpor. The implications for these newly recognized upregulated mRNAs for hibernation as well as more global issues of maintaining steady-state levels of mRNA during torpor are discussed.

scholarly journals Triosephosphate isomerase deficiency: consequences of an inherited mutation at mRNA, protein and metabolic levels

2005 ◽  
Vol 392 (3) ◽  
pp. 675-683 ◽  
Author(s):  
Judit Oláh ◽  
Ferenc Orosz ◽  
László G. Puskás ◽  
László Hackler ◽  
Margit Horányi ◽  
...  
Keyword(s):  
Steady State ◽  
Triosephosphate Isomerase ◽  
Specific Activity ◽  
Energy State ◽  
Dihydroxyacetone Phosphate ◽  
Peptidase Activity ◽  
Mrna Levels ◽  
Regulatory Enzymes ◽  
Computational Data ◽  
Fructose 1,6 Bisphosphate

Triosephosphate isomerase (TPI) deficiency is a unique glycolytic enzymopathy coupled with neurodegeneration. Two Hungarian compound heterozygote brothers inherited the same TPI mutations (F240L and E145Stop), but only the younger one suffers from neurodegeneration. In the present study, we determined the kinetic parameters of key glycolytic enzymes including the mutant TPI for rational modelling of erythrocyte glycolysis. We found that a low TPI activity in the mutant cells (lower than predicted from the protein level and specific activity of the purified recombinant enzyme) is coupled with an increase in the activities of glycolytic kinases. The modelling rendered it possible to establish the steady-state flux of the glycolysis and metabolite concentrations, which was not possible experimentally due to the inactivation of the mutant TPI and other enzymes during the pre-steady state. Our results showed that the flux was 2.5-fold higher and the concentration of DHAP (dihydroxyacetone phosphate) and fructose 1,6-bisphosphate increased 40- and 5-fold respectively in the erythrocytes of the patient compared with the control. Although the rapid equilibration of triosephosphates is not achieved, the energy state of the cells is not ‘sick’ due to the activation of key regulatory enzymes. In lymphocytes of the two brothers, the TPI activity was also lower (20%) than that of controls; however, the remaining activity was high enough to maintain the rapid equilibration of triosephosphates; consequently, no accumulation of DHAP occurs, as judged by our experimental and computational data. Interestingly, we found significant differences in the mRNA levels of the brothers for TPI and some other, apparently unrelated, proteins. One of them is the prolyl oligopeptidase, the activity decrease of which has been reported in well-characterized neurodegenerative diseases. We found that the peptidase activity of the affected brother was reduced by 30% compared with that of his neurologically intact brother.

Cyclic AMP analogs and retinoic acid influence the expression of retinoic acid receptor alpha, beta, and gamma mRNAs in F9 teratocarcinoma cells

1990 ◽  
Vol 10 (1) ◽  
pp. 391-396
Author(s):  
L Hu ◽  
L J Gudas
Keyword(s):  
Retinoic Acid ◽  
Steady State ◽  
Cyclic Amp ◽  
Cellular Response ◽  
Retinoic Acid Receptor ◽  
Mrna Level ◽  
Mrna Levels ◽  
Protein Synthesis Inhibitors ◽  
Receptor Alpha ◽  
F9 Teratocarcinoma

Retinoic acid (RA) receptor alpha (RAR alpha) and RAR gamma steady-state mRNA levels remained relatively constant over time after the addition of RA to F9 teratocarcinoma stem cells. In contrast, the steady-state RAR beta mRNA level started to increase within 12 h after the addition of RA and reached a 20-fold-higher level by 48 h. This RA-associated RAR beta mRNA increase was not prevented by protein synthesis inhibitors but was prevented by the addition of cyclic AMP analogs. In the presence of RA, cyclic AMP analogs also greatly reduced the RAR alpha and RAR gamma mRNA levels, even though cyclic AMP analogs alone did not alter these mRNA levels. The addition of either RA or RA plus cyclic AMP analogs did not result in changes in the three RAR mRNA half-lives. These results suggest that agents which elevate the internal cyclic AMP concentration may also affect the cellular response to RA by altering the expression of the RARs.

Sign in / Sign up

Export Citation Format

Share Document