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Increased Protein Expression (increased + protein_expression)
Selected AbstractsFaster clearance of omeprazole in mutant Nagase analbuminemic rats: possible roles of increased protein expression of hepatic CYP1A2 and lower plasma protein bindingBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 3 2009Dae Y. Lee Abstract It is well known that there are various changes in the expression of hepatic and intestinal CYPs in mutant Nagase analbuminemic rats (NARs). It has been reported that the protein expression of hepatic CYP1A2 was increased, whereas that of hepatic CYP3A1 was not altered, and it was also found that the protein expression of the intestinal CYP1A subfamily significantly increased in NARs from our other study. In addition, in this study additional information about CYP changes in NARs was obtained; the protein expression of the hepatic CYP2D subfamily was not altered, but that of the intestinal CYP3A subfamily increased in NARs. Because omeprazole is metabolized via hepatic CYP1A1/2, 2D1, 3A1/2 in rats, it could be expected that the pharmacokinetics of omeprazole would be altered in NARs. After intravenous administration of omeprazole to NARs, the Clnr was significantly faster than in the controls (110 versus 46.6 ml/min/kg), and this could be due to an increase in hepatic metabolism caused by a greater hepatic CYP1A2 level in addition to greater free fractions of the drug in NARs. After oral administration of omeprazole to NARs, the AUC was also significantly smaller (80.1% decrease) and F was decreased in NARs. This could be primarily due to increased hepatic and intestinal metabolism caused by greater hepatic CYP1A2 and intestinal CYP1A and 3A levels. In particular, the smaller F could mainly result from greater hepatic and intestinal first-pass effect in NARs than in the controls. Copyright © 2009 John Wiley & Sons, Ltd. [source] Anti-apoptotic genes Aven and E1B-19K enhance performance of BHK cells engineered to express recombinant factor VIII in batch and low perfusion cell cultureBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2007Toey Nivitchanyong Abstract The engineering of production cell lines to express anti-apoptotic genes has been pursued in recent years due to potential process benefits, including enhanced cell survival, increased protein expression, and improved product quality. In this study, a baby hamster kidney cell line secreting recombinant factor VIII (BHK-FVIII) was engineered to express the anti-apoptotic genes Aven and E1B-19K. In high cell density shake flask culture evaluation, 11 clonal cell lines expressing either E1B-19K or a combination of Aven and E1B-19K showed improved survival compared to both parental and blank vector cell line controls. These cell lines exhibited lower caspase-3 activation and reduced Annexin-V binding compared to the controls. Parental and blank vector cell lines were less than 50% viable after 48 h of exposure to thapsigargin while cell lines expressing E1B-19K with or without Aven maintained viabilities approaching 90%. Subsequently, the best Aven-E1B-19K candidate cell line was compared to the parental cell line in 12-L perfusion bioreactor studies. Choosing the appropriate perfusion rates in bioreactors is a bioprocess optimization issue, so the bioreactors were operated at sequentially lower specific perfusion rates, while maintaining a cell density of 2,×,107 viable cells/mL. The viability of the parental cell line declined from nearly 100% at a perfusion rate of 0.5 nL/cell/day to below 80% viability, with caspase-3 activity exceeding 15%, at its lower perfusion limit of 0.15 nL/cell/day. In contrast, the Aven-E1B-19K cell line maintained an average viability of 94% and a maximum caspase-3 activity of 2.5% even when subjected to a lower perfusion minimum of 0.1 nL/cell/day. Factor VIII productivity, specific growth rate, and cell size decreased for both cell lines at lower perfusion rates, but the drop in all cases was larger for the parental cell line. Specific consumption of glucose and glutamine and production of lactate were consistently lower for the Aven-E1B-19K culture. Furthermore, the yield of ammonia from glutamine increased for the Aven-E1B-19K cell line relative to the parent to suggest altered metabolic pathways following anti-apoptosis engineering. These results demonstrate that expression of anti-apoptotic genes Aven and E1B-19K can increase the stability and robustness of an industrially relevant BHK-FVIII mammalian cell line over a wide range of perfusion rates. Biotechnol. Bioeng. 2007; 98: 825,841. © 2007 Wiley Periodicals, Inc. [source] Paradoxical early glucocorticoid induction of stem cell factor (SCF) expression in inflammatory conditionsBRITISH JOURNAL OF PHARMACOLOGY, Issue 1 2004Carla Alexandra Da Silva Stem cell factor (SCF) is a major growth factor for mast cells, promoting their differentiation and chemotaxis. Its expression is regulated by glucocorticoids in inflammatory conditions, showing an early increased protein expression, before the expected anti-inflammatory decrease (Da Silva et al., Br. J. Pharmacol. 2002:135,1634). We here evaluated the early kinetic of SCF expression regulated by interleukin (IL)-1,, budesonide and the combination of both in human lung fibroblasts in culture. Budesonide potentiated the IL-1, -enhanced expression of SCF mRNA (+103%) and protein (+98%) very shortly after treatment (at 30 min and 1 h, respectively). A gentle downregulation followed. This potentiating effect of budesonide was related to increased SCF mRNA stability and SCF gene transcription. Deletion of a ,B-like site that we identified in the first intron of the SCF gene, in a luciferase reporter system, abolished the potentiation by budesonide, as well as the effect of IL-1, alone, as compared to the wild-type construction activity. All budesonide-induced effects were glucocorticoid-receptor dependent, since they were reproduced by dexamethasone and blocked by RU486. IL-1,+budesonide did not affect the relative expression of the soluble and membrane-bound forms of SCF. In conclusion, our results clearly show that glucocorticoids act very early to adversely increase the expression of SCF mRNA and protein in the inflammatory conditions created by IL-1,, and that this effect involves increased mRNA stability and increased gene expression through activation of the NF- ,B-like responsive element. British Journal of Pharmacology (2004) 141, 75,84. doi:10.1038/sj.bjp.0705598 [source] Protection of Mouse Brain from Aluminum-induced Damage by Caffeic AcidCNS: NEUROSCIENCE AND THERAPEUTICS, Issue 1 2008Jun-Qing Yang The natural product caffeic acid is a specific inhibitor of 5-lipoxygenase (5-LOX); it also possesses antioxidant and antiinflammatory properties. The current study was designed to determine whether the neuroprotective properties of caffeic acid are due to inhibition of 5-LOX. Cerebral damage was induced in mice by intracerebroventricular microinjection of aluminum (5.0 ,g aluminum in 2.0 ,L, once a day, for 5 days). Caffeic acid was administered intragastrically at 30 min prior to aluminum and repeated daily for an additional 10 days. The brain injury was determined by observation of behavioral changes in mice, as well as by measuring biochemical and pathological changes in the cerebral tissue. The levels of 5-LOX proteins and 5-LOX mRNA expression were measured in brain tissue. Aluminum impaired learning and memory in mice produced neuronal death in hippocampi, elevated brain malondialdehyde levels, increased protein expression of amyloid precursor protein (APP), amyloid beta, and 5-LOX. It also increased 5-LOX mRNA expression and decreased choline acetyl transferase (ChAT) protein expression in the brain tissue of mice. Caffeic acid prevented brain damage as well as behavioral and biochemical changes caused by aluminum overload. The results of this study suggest that overexpression of 5-LOX accompanies the cerebral injury induced by aluminum overload in mice, and that selective inhibitors of 5-LOX may have potential value in the treatment of aluminum neurotoxicity and conceivably of diseases associated with neuronal injury. [source] | |||||||||||||