scholarly journals Hepatic Effects of Phthalate Esters and Related Compounds. In Vivo and In Vitro Correlations

1986 ◽  
Vol 67 ◽  
pp. 283 ◽  
Author(s):  
Brian G. Lake ◽  
Tim J. B. Gray ◽  
Sharat D. Gangolli
Keyword(s):  
Phthalate Esters ◽  
Related Compounds

scholarly journals Evidence that the metabolite repair enzyme NAD(P)HX epimerase has a moonlighting function

2018 ◽  
Vol 38 (3) ◽  
Author(s):  
Thomas D. Niehaus ◽  
Mona Elbadawi-Sidhu ◽  
Lili Huang ◽  
Laurence Prunetti ◽  
Jesse F. Gregory ◽  
...  
Keyword(s):  
Vitamin B6 ◽  
Weakly Bound ◽  
E Coli ◽  
Essentially Normal ◽  
Metabolite Repair ◽  
Mutant Cells ◽  
Dehydratase Activity ◽  
Related Compounds

NAD(P)H-hydrate epimerase (EC 5.1.99.6) is known to help repair NAD(P)H hydrates (NAD(P)HX), which are damage products existing as R and S epimers. The S epimer is reconverted to NAD(P)H by a dehydratase; the epimerase facilitates epimer interconversion. Epimerase deficiency in humans causes a lethal disorder attributed to NADHX accumulation. However, bioinformatic evidence suggest caution about this attribution by predicting that the epimerase has a second function connected to vitamin B6 (pyridoxal 5′-phosphate and related compounds). Specifically, (i) the epimerase is fused to a B6 salvage enzyme in plants, (ii) epimerase genes cluster on the chromosome with B6-related genes in bacteria, and (iii) epimerase and B6-related genes are coexpressed in yeast and Arabidopsis. The predicted second function was explored in Escherichia coli, whose epimerase and dehydratase are fused and encoded by yjeF. The putative NAD(P)HX epimerase active site has a conserved lysine residue (K192 in E. coli YjeF). Changing this residue to alanine cut in vitro epimerase activity by ≥95% but did not affect dehydratase activity. Mutant cells carrying the K192A mutation had essentially normal NAD(P)HX dehydratase activity and NAD(P)HX levels, showing that the mutation had little impact on NAD(P)HX repair in vivo. However, these cells showed metabolome changes, particularly in amino acids, which exceeded those in cells lacking the entire yjeF gene. The K192A mutant cells also had reduced levels of ‘free’ (i.e. weakly bound or unbound) pyridoxal 5'-phosphate. These results provide circumstantial evidence that the epimerase has a metabolic function beyond NAD(P)HX repair and that this function involves vitamin B6.

scholarly journals Antischistosomal Activities of Mefloquine-Related Arylmethanols

2012 ◽  
Vol 56 (6) ◽  
pp. 3207-3215 ◽  
Author(s):  
Katrin Ingram ◽  
William Ellis ◽  
Jennifer Keiser
Keyword(s):  
Body Weight ◽  
Worm Burden ◽  
Structural Features ◽  
Content Type ◽  
Antischistosomal Activity ◽  
Oral Doses ◽  
Related Compounds ◽  
Insight Into

ABSTRACTInteresting antischistosomal properties have been documented for the antimalarial mefloquine, a 4-quinolinemethanol. We evaluated the antischistosomal activities of nine mefloquine-related compounds belonging to the 4-pyridinemethanols, 9-phenanthrenmethanols, and 4-quinolinemethanols. Eight compounds revealed high activities againstSchistosoma mansoni in vitro, with two drugs (the 4-quinolinemethanols WR7573 and WR7930) characterized by significantly lower half-maximal inhibitory concentrations (IC50s) (2.7 and 3.5 μM, respectively) compared to mefloquine (11.4 μM). Mefloquine and WR7930 showed significantly decreased IC50s when incubated in the presence of hemoglobin. High worm burden reductions (WBR) were obtained with enpiroline (WBR, 82.7%; dosage, 200 mg/kg of body weight) and itsthreoisomers (+)-threo(WBR, 100%) and (−)-threo(WBR, 89%) and with WR7930 (WBR, 87%; dosage, 100 mg/kg) against adultS. mansoniin mice. Furthermore, excellentin vitroandin vivoantischistosomal activity was observed for two WR7930-related structures (WR29252 and WR7524). In addition, mefloquine (WBR, 81%), enpiroline (WBR, 77%), and WR7930 (WBR, 100%) showed high activities againstS. haematobiumharbored in mice following single oral doses of 200 mg/kg. These results provide a deeper insight into the structural features of the arylmethanols that rule antischistosomal activity. Further studies should be launched with enpiroline and WR7930.

The Morphological Effects of Phthalate Esters on Rat Sertoli Cells in vivo and in vitro

1988 ◽  
Vol 7 (2) ◽  
pp. 225-226
Author(s):  
D.M. Creasy ◽  
L.M. Beech ◽  
T.J.B. Gray
Keyword(s):  
Sertoli Cells ◽  
Phthalate Esters

Anticatalase Activity « in vitro » and « in vivo » of Cysteine, Tyrosine and Some Related Compounds, and its Significance for the Anticatalase Activity of Tumors.

1965 ◽  
Vol 51 (6) ◽  
pp. 433-439
Author(s):  
Giovanni Ceriotti ◽  
Luigi Spandrio ◽  
Angelo Agradi
Keyword(s):  
Vitro Activity ◽  
In Vitro Activity ◽  
Similar Action ◽  
Related Compounds

Like cysteine and some of its derivatives, tyrosine inhibits liver catalase not only « in vitro » but also « in vivo ». Among the analogues of tyrosine tested, dihydroxyphenylalanine and dihydroxyphenethylamine possess « in vitro » the same activity as tyrosine; the activity of p-hydroxyphenylethanolamine is lower; phenylalanine is inactive. The «in vitro» activity seems to be directly correlated with the auto-oxidability of the various compounds. None of the analogues of tyrosine tested was active «in vivo». The depressing activity of cysteine and of tyrosine on liver catalase apparently has no relationship with the similar action of tumors.

In vitro and in vivo anti-influenza virus activities of flavonoids and related compounds as components of Brazilian propolis (AF-08)

2014 ◽  
Vol 8 ◽  
pp. 214-223 ◽  
Author(s):  
Hisahiro Kai ◽  
Masatsugu Obuchi ◽  
Hiroki Yoshida ◽  
Wataru Watanabe ◽  
Shigetoshi Tsutsumi ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Brazilian Propolis ◽  
Related Compounds

scholarly journals The Escherichia coli gabDTPC Operon: Specific γ-Aminobutyrate Catabolism and Nonspecific Induction

2002 ◽  
Vol 184 (24) ◽  
pp. 6976-6986 ◽  
Author(s):  
Barbara L. Schneider ◽  
Stephen Ruback ◽  
Alexandros K. Kiupakis ◽  
Hillary Kasbarian ◽  
Christine Pybus ◽  
...  
Keyword(s):  
Nitrogen Source ◽  
Nitrogen Limitation ◽  
Nitrogen Sources ◽  
Wild Type ◽  
Gaba A ◽  
Specific Induction ◽  
Related Compounds ◽  
Type Strains

ABSTRACT Nitrogen limitation induces the nitrogen-regulated (Ntr) response, which includes proteins that assimilate ammonia and scavenge nitrogen. Nitrogen limitation also induces catabolic pathways that degrade four metabolically related compounds: putrescine, arginine, ornithine, and γ-aminobutyrate (GABA). We analyzed the structure, function, and regulation of the gab operon, whose products degrade GABA, a proposed intermediate in putrescine catabolism. We showed that the gabDTPC gene cluster constitutes an operon based partially on coregulation of GabT and GabD activities and the polarity of an insertion in gabT on gabC. A ΔgabDT mutant grew normally on all of the nitrogen sources tested except GABA. The unexpected growth with putrescine resulted from specific induction of gab-independent enzymes. Nac was required for gab transcription in vivo and in vitro. Ntr induction did not require GABA, but various nitrogen sources did not induce enzyme activity equally. A gabC (formerly ygaE) mutant grew faster with GABA and had elevated levels of gab operon products, which suggests that GabC is a repressor. GabC is proposed to reduce nitrogen source-specific modulation of expression. Unlike a wild-type strain, a gabC mutant utilized GABA as a carbon source and such growth required σS. Previous studies showing σS-dependent gab expression in stationary phase involved gabC mutants, which suggests that such expression does not occur in wild-type strains. The seemingly narrow catabolic function of the gab operon is contrasted with the nonspecific (nitrogen source-independent) induction. We propose that the gab operon and the Ntr response itself contribute to putrescine and polyamine homeostasis.

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