Search results for "Agens"

Liver subcellular fractions from rats treated by organosulfur compounds from Allium modulate mutagen activation

2000

The effects of in vivo administration of naturally occurring organosulfur compounds (OSCs) from Allium species were studied on the activation of several mutagens. Male SPF Wistar rats were given p.o. one of either diallyl sulfide (DAS), diallyl disulfide (DADS), dipropyl sulfide (DPS) or dipropyl disulfide (DPDS) during 4 consecutive days and the ability of hepatic S9 and microsomes from treated rats to activate benzo[a]pyrene (BaP), cyclophosphamide (CP), dimethylnitrosamine (DMN), N-nitrosopiperidine (N-PiP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was determined in the Ames test. Administration of DAS, DPS and DPDS resulted in a significant increase of the activation of…

The effect of biological sealants and adhesive treatments on matrix metalloproteinase expression during renal injury healing

2017

Background Renal injuries are relatively common in cases of abdominal trauma. Adhesives and sealants can be used to repair and preserve damaged organs. Using a rat model, this study explores the activity of different matrix metalloproteinases (MMP) during the healing of renal injuries treated by two biological adhesives (TachoSil and GelitaSpon) and a new synthetic elastic cyanoacrylate (Adhflex). Methods Renal traumatic injuries were experimentally induced in 90 male Wistar rats by a Stiefel Biopsy Punch in the anterior aspect of the left kidney. Animals were divided into five groups: 1, sham non-injured (n = 3); 2, non-treated standard punch injury (n = 6); 3, punch injury treated with Ta…

Mechanical strain causes adaptive change in bronchial fibroblasts enhancing profibrotic and inflammatory responses

2016

Asthma is characterized by periodic episodes of bronchoconstriction and reversible airway obstruction; these symptoms are attributable to a number of factors including increased mass and reactivity of bronchial smooth muscle and extracellular matrix (ECM) in asthmatic airways. Literature has suggested changes in cell responses and signaling can be elicited via modulation of mechanical stress acting upon them, potentially affecting the microenvironment of the cell. In this study, we hypothesized that mechanical strain directly affects the (myo)fibroblast phenotype in asthma. Therefore, we characterized responses of bronchial fibroblasts, from 6 normal and 11 asthmatic non-smoking volunteers,…

Genotoxic potential of by-products in drinking water in relation to water disinfection: Survey of pre-ozonated and post-chlorinated drinking water by…

2006

Mutagenic potential of drinking water samples derived from ranneywells was studied. 100-100 l of untreated (rough) and ozone-treated as well as chlorinated-disinfected water were dropped on and adsorbed by macroreticular resin columns (Serdolit PAD-III and Amberlite XAD-2). The adsorbed material was desorbed by methanol and dichloromethane. After elimination of the solvents by vacuum distillation the adsorbed material was dissolved in dimethylsulfoxide. The mutagenic activity was tested in the Ames-Salmonella/rat liver microsome system. The tester strains were TA-98 and TA-100. The material adsorbed to Serdolit PAD-III from rough and also disinfected water did not induce mutagenicity in cas…

In vivo antigenotoxic effects of dietary allyl sulfides in the rat

1997

The effects of dietary administration of diallyl sulfide (DAS), diallyl disulfide (DADS) and allyl mercaptan (AM) on the genotoxicity of different chemicals were studied in two experimental systems: (i) measurement of hepatic DNA single-strand breaks induced in rats by aflatoxin B1 (AFB1), N-nitrosodimethylamine (NDMA) or methylnitrosourea (MNU); (ii) mutagenicity of AFB1 or NDMA on Salmonella typhimurium TA100 using hepatic S9 from rats fed allyl sulfides as the activation system. All compounds strongly reduced hepatic DNA breaks induced by AFB1 and NDMA but did not modify the genotoxicity of MNU. In the Ames test, the mutagenicity of NDMA was strongly inhibited by hepatic S9 from rats fed…

Metabolic activation to a mutagen of 3-hydroxy-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene, a secondary metabolite of benzo[a]pyrene

1987

3-Hydroxy-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (3-OH-BP-7,8-diol) was isolated from arylsulfatase/beta-glucuronidase-treated bile of rats to which 3-hydroxybenzo[a]pyrene (3-OH-BP) has been administered. This triol was investigated for mutagenicity in Salmonella typhimurium (reversion to histidine prototrophy of strains TA 97, TA 98, TA 100 and TA 1537) and in V79 Chinese hamster cells (acquisition of resistance to 6-thioguanine). When no exogenous metabolizing system was added the triol was inactive, while 3-OH-BP showed weak mutagenic effects with all four bacterial strains. In the presence of NADPH-fortified postmitochondrial supernatant fraction (S9 mix) of liver homogenate fro…

Clavine alkaloids and derivatives as mutagens detected in the Ames test.

1992

Eight cytostatic clavines were investigated for mutagenicity in Salmonella typhimurium (reversion of the his-strains TA98, TA100, TA102 and TA1537), directly and in the presence of a mammalian xenobiotic metabolizing system, S9 (NADPH-fortified postmitochondrial fraction of liver homogenate from Aroclor 1254-treated rats). Four compounds (festuclavine, 17-bromofestuclavine, 1-allylelymoclavine and 1-methyllysergol methyl ether) were direct mutagens, whose activity was enhanced in the presence of S9. The other compounds (1-cyclopentylfestuclavine, 13-bromo-1-cyclopropylmethylfestuclavine, 6-cyano-1-propyl-6-norfestuclavine and 6-allyl-1-propyl-6-norfestuclavine) showed mutagenic effects only…

The mutagenicity of MCPA and its soil metabolites, chlorinated phenols, catechols and some widely used slimicides in Finland

1977

Modulation of the control of mutagenic metabolites derived from cyclophosphamide and ifosfamide by stimulation of protein kinase A

1990

The phosphorylation of the 2 major phenobarbital-inducible cytochrome P450 isoenzymes IIB1 and IIB2 was increased in intact hepatocytes by the action of the membrane-permeating cAMP derivative N6,O2'-dibutyryl-cAMP. Under these conditions cyclophosphamide and ifosfamide (which are known to be activated by cytochrome P450 IIB1) were investigated for mutagenicity in Salmonella typhimurium TA1535 and TA100 and for cytotoxicity in TA1535. Cyclophosphamide and ifosfamide were transformed to mutagenic and cytotoxic metabolites by the hepatocytes. The activation of both drugs to mutagens was markedly reduced after pretreatment of the hepatocytes with the membrane-permeating cAMP derivative N6,O2'-…

Species differences in activating and inactivating enzymes related to the control of mutagenic metabolites

1977

Microsomal monooxygenases catalyze the biosynthesis of epoxides from olefinic and aromatic compounds whilst microsomal epoxide hydratase and cytoplasmic glutathione S-transferases are responsible for their further biotransformation. Although catalytically very efficient the cytoplasmic glutathione S-transferases play, due to their subcellular localization, a minor role in the inactivation of epoxides derived from large lipophilic compounds and were, therefore, not included in this study. It was shown with such a lipophilic compound, benzo(a)pyrene, as a model substance and with liver enzyme mediated bacterial mutagenesis as biological endpoint that species and strain differences in epoxide …