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PubMed2000

Hydrazine reagents as derivatizing agents in environmental analysis--a critical review.

Hydrazine reagents are a well-known group of derivatizing agents for the determination of aldehydes and ketones in liquid and gaseous samples. Within this article, the most important hydrazine reagents are critically summarized, and their major applications in different fields, including environmental analysis, food chemistry and industrial analysis are introduced. As 2,4-dinitrophenylhydrazine (DNPH) is the basic reagent for several international standard procedures, its properties are discussed in detail. Particular focus is directed on the chemistry of the hydrazine reagents, and chemical interferences are considered. Recent methods for the determination of various oxidants using hydrazine reagents are presented as well. Due to limited space, this review does not cover the related field of carbohydrate analysis, although many chemical aspects are similar.

Aldehydes↗
PubMed1983

A spectrophotometric, enzymatic assay for D-3-hydroxybutyrate that is not dependent on hydrazine.

Because of the potential carcinogenic properties of hydrazine and because of other health hazards associated with its use in the laboratory, an enzymatic assay has been developed for D-3-hydroxybutyrate that is not dependent on hydrazine to drive the reaction toward completion. The use of a high concentration of NAD+ and a buffer at pH 9.5 resulted in a favorable conversion of D-3-hydroxybutyrate to acetoacetate by D-3-hydroxybutyrate dehydrogenase even though the reaction favors D-3-hydroxybutyrate formation under physiological conditions. The assay was also completed faster than previous assays using hydrazine so that the amount of enzyme used for the assay could be reduced. The recovery of D-3-hydroxybutyrate added to liver samples was 98 +/- 1% (mean +/- SEM, n = 6). The assay was found to be suitable for the measurement of D-3-hydroxybutyrate in samples such as perchloric acid extracts of isolated hepatocytes even when the acetoacetate to D-3-hydroxybutyrate ratio was 4 to 1. This assay presents a reliable alternative to the use of hydrazine and may be used for the assay of D-3-hydroxybutyrate in a variety of physiological and experimental samples.

3-Hydroxybutyric Acid↗
PubMed1985

Structural elucidation of glycosaminoglycans through characterization of disaccharides obtained after fragmentation by hydrazine-nitrous acid treatment.

Hydrazinolysis of glycosaminoglycans to bring about N-deacetylation followed by nitrous acid treatment to effect deaminative cleavage at alternating hexosamine residues has been used to make possible identification and quantitation of disaccharide sequences and position of O-sulfate substitution in nanogram amounts of these polymers. After radiolabeling by NaB3H4 reduction the hydrazine-nitrous acid products were fractionated on Dowex 1 and further resolved by thin-layer chromatography into disaccharides terminating in either sulfated or unsulfated anhydromannitol or anhydrotalitol. Fragmentation of hyaluronic acid, keratan sulfate, chondroitin 4-sulfate, chondroitin 6-sulfate, dermatan sulfate, and heparin yielded a total of 14 disaccharides comprising the major sequences (greater than 1 mol%) occurring in mammalian glycosaminoglycans. Disaccharides representing the predominant variants of the chondroitin sulfates [GlcUA beta 1----3anhydrotalitol(4-SO4) and GlcUA beta 1----3anhydrotalitol(6-SO4)] as well as of dermatan sulfate chains [IdUA alpha 1----3anhydrotalitol(4-SO4) and GlcUA beta 1----3anhydrotalitol(4-SO4)] chains could readily be quantitated by this approach. In the case of heparin a comparison of the disaccharides produced by direct nitrous acid and hydrazine-nitrous acid treatments moreover provided an assessment of the distribution of N-sulfate groups. The characterization of the various disaccharides by Smith periodic acid degradation and glycosidase digestions was facilitated by the preparation and thin-layer chromatographic resolution of the complete series of monosulfated derivatives of anhydromannitol and anhydrotalitol; the sulfate esters were shown to be stable to both the hydrazine and nitrous acid treatments. The high sensitivity of the hydrazine-nitrous acid fragmentation procedure should prove useful in the structural elucidation of cell surface and basement membrane proteoglycans as well as other sulfated glycoconjugates which are present in small amounts.

Animals↗
PubMed1983

Induction of megamitochondria in the mouse and rat livers by hydrazine.

The correlation between structures of chemicals and their inducibility for megamitochondrial formation was investigated. Since the chemical structure universal to the inducers of megamitochondria previously reported (cuprizone and isonicotinic acid derivatives) is the carbazoyl group (-CONHNH2), semicarbazide (NH2NHCONH2) was tested first. Then, hydrazine (NH2NH2) was tested, replacing the carbazoyl group of semicarbazide by an amino group (-NH2). The present study demonstrates that (1) megamitochondria were induced in mouse and rat hepatocytes by feeding the animals with a diet containing semicarbazide or hydrazine, suggesting that the carbazoyl group was not essential for megamitochondrial formation; (2) hydrazine-induced megamitochondrial formation was a reversible process. Coupling efficiencies and activities of ATPase and cytochrome oxidase of megamitochondria induced by hydrazine were slightly decreased, while the activity of monoamine oxidase was moderately decreased. Freeze-fracture electron microscopy revealed particle-free regions in the outer membranes of megamitochondria fixed with glutaraldehyde at 22 degrees C; the regions disappeared at 25 degrees C, indicating that the temperature of the liquid crystalline to gel state lipid phase transition in the megamitochondrial outer membrane was elevated. It is speculated that chemical structure of inducer of megamitochondria could be simplified to NH2-G (G, substituting group).

Aging↗
PubMed1993

Deglycation of glycated proteins with hydrazine analogues.

Glycated human serum albumin (glc HSA) and glc proteins in back hairs from diabetic rats were deglycated by incubation with hydrazine or aminoguanidine (guanylhydrazine) at physiological temperature (37 degrees C). Glc HSA decreased by 35% with 0.2 M hydrazine at day 20 and by 56% with 0.1 M aminoguanidine at day 10. The glc proteins in hairs decreased by 40-50% and 70-77% with hydrazine and aminoguanidine at more than 0.1 M by day 20, respectively. The deglycation of glc protein with aminoguanidine was slower than that with hydrazine. The present result suggests that the inhibitory effects by aminoguanidine on the late Maillard reaction may include a decrease in the level of glc proteins (Amadori compounds) due to deglycation.

Animals↗
PubMed1976

Fixation and loss of hydrazine-induced premutational damage in Haemophilus influenzae.

Premutational damage induced in Haemophilus influenzae by hydrazine appears to be fixed as final mutation only at replication as judged by the transformation assay. Fixation at replication is independent of the rec1 gene, unlike the case with nitrosocarbaryl. Prior to replication premutational damage induced by hydrazine disappears by an unknown process that is not dependent on the presence of a pyrimidine dimer excision system nor on the rec1 gene. Hydrazine does not produce detectable single-strand breaks or alkali-labile sites in the treated DNA nor gaps in DNA newly synthesized after treatment. In these respects it also differs from nitroso compounds. It is concluded that hydrazine acts to produce and altered base, possibly N(4)-aminocytosine, that produces mutations by mispairing at replication rather than by error-prone repair.

Chromosomes, Bacterial↗
PubMed1979

Enhancement by transition metals of unscheduled DNA synthesis induced by isoniazid and related hydrazines in cultured normal and xeroderma pigmentosum human cells.

In combination with transition metals (Mn(II), Cu(II), and Fe(III)), isoniazid and related hydrazine compounds induced unscheduled DNA synthesis (DNA repair) in cultured human fibroblasts. Manganese at 10(-5) and 10(-4) M strongly enhanced DNA repair induced by isoniazid, iproniazid, nialamide and hydrazine. Peak levels of DNA repair occurred at 5 x 10(-4)--10(-3) M of the 4 hydrazine compounds. Copper caused less enhancement of DNA repair while iron had no detectable effect. Without added metal, unscheduled DNA synthesis was not observed in cells treated with any of the 4 freshly-prepared hydrazine compounds. However, following preincubation in medium for 6--12 h, isoniazid alone at high concentrations (10(-2) M--10(-1) M) induced DNA repair. With isoniazid/manganese mixtures, preincubation did not further enhance DNA repair except at low concentrations of isoniazid (2--5 x 10(-4) M). Catalase reduced the DNA damage caused by preincubated isoniazid and by the isoniazid/metal mixtures. Exposure of repair-deficient xeroderma pigmentosum cells to isoniazid plus manganese resulted in a DNA-repair profile similar to that of normal cells. The results are consistent with hydrogen peroxide being a critical intermediate for the production of free radicals which cause the observed DNA damage.

Cells, Cultured↗
PubMedDate not supplied

Effect of hydrazine sulfate on glucose-regulating enzymes in the normal and cancerous rat.

Glucokinase, hexokinase, fructose 1,6-bisphosphatase and phosphoenolpyruvate carboxykinase specific activities were monitored in liver cytosol from rats that had been made cancerous with 1,2-dimethylhydrazine and then treated with hydrazine sulfate. The presence of intestinal cancer, specifically, was confirmed by laparotomy and by histological analysis. Sustained changes in hexokinase and glucokinase specific activities were first evident during the latter weeks that the carcinogen was being administered. Upon subsequent treatment with hydrazine sulfate, glucokinase activity further decreased, and liver cytosolic phosphoenolpyruvate carboxykinase activity increased. Liver cytosolic hexokinase and fructose 1,6-bisphosphatase specific activities were not appreciably affected by the hydrazine sulfate treatment. These results indicate that hydrazine sulfate may influence carbohydrate metabolism at the level of selected liver enzymes not only with respect to gluconeogenesis, but also in terms of glucose uptake.

1,2-Dimethylhydrazine↗
PubMed1981

Comparative mutagenicity of hydrazine and 3 methylated derivatives in L5178Y mouse lymphoma cells.

The mutagenicity of hydrazine, monomethylhydrazine (MMH), 1,1-dimethylhydrazine (UDMH) and 1,2-dimethylhydrazine (SDMH) in L5178Y mouse-lymphoma cells has been investigated. Hydrazine, UDMH and SDMH induced thymidine mutation, in the absence of extraneous metabolic activation. Dose-response curves were produced for these compounds. MMH did not induce thymidine mutation. All 4 compounds were negative in the ouabain, thioguanine and cytosine arabinoside selective systems. Induction of mutation by hydrazine and UDMH is correlated with toxicity. This is not the case for SDMH-induced mutation. Hydrazine, UDMH and SDMH produce different ratios of large and small thymidine-resistant clones. The compounds appear to have different modes of action in the cell.

Animals↗
PubMed1982

Induction of unscheduled DNA synthesis in the germ cells of male mice after treatment with hydrazine or procarbazine.

The induction of unscheduled DNA synthesis (UDS) in early spermatid stages of mice was studied after treatment with hydrazine or procarbazine (Natulan). The UDS response was assayed by measuring the levels of [3H]dThd in the nuclei of sperm cells derived from treated and untreated early spermatid stages. The radioactivity present in these nuclei was measured by liquid scintillation counting. Mice were also treated with 100 mg/kg of MMS in order to compare the UDS level induced by this chemical with that induced by hydrazine or procarbazine. The level of UDS induced by hydrazine was not significantly different from that of the untreated controls in any of the 5 doses tested (10-120 mg/kg). Procarbazine, on the contrary, induced UDS in all the 5 doses tested, from 50 to 600 mg/kg. The increase in the UDS response was positively correlated with the increasing dose. The present results with hydrazine indicate either that this compound does not reach the germ cells in sufficient amounts to produce DNA damage or that the repair system in early spermatid stages does not recognize the type of DNA damage produced by this compound. The sensitivity of detection of UDS in the germ cells of male mice is compared with that of the rabbit. At equivalent germ-cell stages and dosage the mouse UDS assay is more sensitive, by a factor of 2 to 3, than the rabbit assay for the induction of UDS by procarbazine and MMS.

Animals↗
PubMed1995

High-performance liquid chromatographic determination of isoniazid, acetylisoniazid and hydrazine in biological fluids.

The basic principle of derivatization of a hydrazide moiety with an aldehyde as applied in the method developed by Lacroix et al. [J. Chromatogr., 307 (1984) 137-144] for the quantitation of isoniazid and acetylisoniazid was improved by modification, standardization and extension to allow quantitation of hydrazine in patient samples. It could be shown that 40 microliters of 1% methanolic cinnamaldehyde per 200 microliters of deproteinized analysate gave maximal chromophoric isoniazid-cinnamaldehyde conjugate, read at 340 nm. The hydrolytic loss of isoniazid, crucial to the quantitation of acetylisoniazid, could be compensated for by introduction of an appropriate set of calibration curves. Although the method described here allows quantitation of monoacetylhydrazine and diacetylhydrazine, in addition to hydrazine, in mono-spiked samples, the method cannot be used for the quantitation of the acetylated metabolites of hydrazine in patient samples because of a lack of specificity. Linear calibration curves in the range 1-25 micrograms/ml for isoniazid and acetylisoniazid, 10-400 ng/ml for hydrazine and 50-1000 ng/ml for monoacetylhydrazine and diacetylhydrazine, could be constructed; analyte recoveries approaching 100% could be achieved in all instances.

Antitubercular Agents↗
PubMed1988

Hydrazine stress in the diabetic: ornithine decarboxylase activity.

Streptozotocin-induced diabetes of 7 weeks duration increased male Sprague-Dawley rat kidney ornithine decarboxylase activity by 4.8-fold but did not affect the liver enzyme. Hydrazine treatment of 4 hr duration stimulated equally kidney ornithine decarboxylase activities of nondiabetic and diabetic rats. Hydrazine treatment increased liver ornithine decarboxylase activity in the nondiabetic rat but did not increase it in the diabetic rat. Since hydrazine stimulates ornithine decarboxylase activity prior to polyamine and protein syntheses, we speculate that the lack of hydrazine stimulation of ornithine decarboxylase in the diabetic liver may be related in part to the unrestrained gluconeogenesis and depressed Kreb's cycle activity: the latter being required for protein synthesis.

Animals↗
PubMed2005

Hydrazide derivatives produce active oxygen species as hydrazine.

It is well documented that some hydrazines are quite sensitive to oxidation and may serve as the electron donor for the reduction of oxygen, whereas hydrazides are not believed to react directly with oxygen. Data presented in this paper show that both hydrazides and hydrazines share an N-N moiety, which is assumed to react with atmospheric oxygen and produce oxygen radicals, at various degrees of efficiency. Since spectrometric measurements of hydrazide just after solubilization showed that the molecular mass remains constant in the absence of oxygen, we can conclude that hydrazides do not react with the oxygen through a slow spontaneous hydrolytic release of hydrazine. However, hydrazine is more reactive than hydrazide, which requires hours rather than minutes to produce measurable quantities of radical species. Differences were also apparent for various substituted derivatives. The reaction was significantly enhanced by the presence of metal ions. Data reported here demonstrate that hydrazides cause irreversible damage to the prosthetic group of proteins as well as causing degradation of the polypeptide chain into small fragments.

Cytochromes c↗
PubMed2006

Deconjugation of N-glucuronide conjugated metabolites with hydrazine hydrate--biomarkers for exposure to the food-borne carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP).

The metabolism of the carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) has been investigated in rabbit liver S9. Two phase I metabolites, N(2)-OH-PhIP and 4'-OH-PhIP were identified based on UV and mass spectra and co-elution with reference standards. Fortification of the incubation with UDGPA resulted in a complete glucuronidation of PhIP and N(2)-OH-PhIP, while 4'-OH-PhIP was only partly glucuronidated. Also, the PhIP metabolite 5-OH-PhIP was completely glucuronidated by rabbit liver S9, while 5-OH-PhIP was a poor substrate for CYP mediated hydroxylation. The glucuronic acid conjugates of PhIP metabolites were unsusceptible to treatment with beta-glucuronidase indicating that these are N-glucuronides. Treatment of the conjugates with hydrazine hydrate, however, resulted in complete hydrolysis of the glucuronic acid conjugates as well as in reduction to the parent amine of metabolites hydroxylated in the exocyclic amino group. Urine was collected from a male volunteer following consumption of fried chicken. Treatment of the urine with beta-glucuronidase/sulfatase resulted in release of 4'-OH-PhIP, while treatment with hydrazine hydrate in addition resulted in release of substantial amounts of PhIP and 5-OH-PhIP. The data show that hydrazine hydrate can hydrolyse N-glucuronides of metabolites of PhIP, glucuronides that are unsusceptible to enzymatic hydrolysis. In addition the data indicate that humans metabolise a large fraction of ingested PhIP to genotoxic metabolites. The chemical hydrolysis of glucuronide conjugates of PhIP metabolites with hydrazine hydrate observed in this study may also be a useful approach in the development of biomarkers for exposure and effect of other xenobiotics.

Animals↗
PubMed2003

Protection of tea melanin on hydrazine-induced liver injury.

The protective activity of melanin derived from tea (MDFT) was studied using hydrazine as a DNA-reactive chemical agent. Intra-peritoneal administration of MDFT at the doses of 5 or 20 mg/kg dose-dependently prevented liver toxicity induced by hydrazine in rats. It normalized rises in serum alanine transferase activity and a decrease in the glutathione level in the liver. It also reduced the hepatic malondialdehyde concentration. Monitoring the intensity of chemiluminescence showed that MDFT could prevent the production of free radicals that are generated owing to metabolic transformation of hydrazine. It also prevented the formation 8-hydroxy-deoxyguanosine (8-OH-dG) DNA adducts. The results obtained in vivo and in vitro suggest that MDFT confers marked protection of the liver against hydrazine-induced oxidative toxicity.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1997

Bioactivation of mushroom hydrazines to mutagenic products by mammalian and fungal enzymes.

Agaritine (N2-[L-(+)-glutamyl]-4-(hydroxymethylphenyl)hydrazine), the principal hydrazine found in the edible mushroom Agaricus bisporus, as well as the N'-acetyl derivative of 4-(hydroxymethyl)phenylhydrazine and 4-(hydroxymethyl)benzene diazonium ion, as the tetraborate salt, considered as the putative proximate and ultimate carcinogens of agaritine, were all synthesised chemically. The mutagenicity of these compounds and of 4-hydrazinobenzoic acid, a precursor of agaritine biosynthesis in mushroom, was investigated in the Ames test, using Salmonella typhimurium strain TA104, in the absence and in the presence of either mushroom tyrosinase or rat hepatic cytosol as activation systems. In the absence of an activation system the diazonium ion was clearly the most mutagenic of the four compounds studied. When tyrosinase was used as activation system, the mutagenicity of N'-acetyl-4-(hydroxymethyl)phenylhydrazine was enhanced; glutathione and superoxide dismutase markedly suppressed the mutagenic response. When the mutagenicity of the four compounds was evaluated in the presence of rat hepatic cytosol, an increase was seen only in the case of N'-acetyl-4-(hydroxymethyl)phenylhydrazine; this was shown to be due to deacetylation releasing the more mutagenic free hydrazine. Collectively, the above data are compatible with an activation of agaritine that involves an initial loss of the gamma-glutamyl group followed by microsomal oxidation of the free hydrazine to generate the diazonium ion. Also of interest is the observation that mushroom tyrosinase can convert N'-acetyl-4-(hydroxymethyl)phenylhydrazine to mutagenic product(s); whether these products contribute to the mutagenicity of mushroom extracts remains to be established.

Agaricus↗
PubMed1992

Mutagenic activity of nine N,N-disubstituted hydrazines in the Salmonella/mammalian microsome assay.

The mutagenic activity of N,N-dimethyl-, N,N-diethyl-, N,N-dibutyl-, N,N-diisobutyl-, N,N-di(p-tolyl)-, N-ethyl-N-phenyl-, N,N-dibenzyl-, N,N-diphenyl- and N,N-diisopropylhydrazine was examined in the Salmonella/mammalian microsome assay using the strains TA1535, TA1537, TA97, TA98, TA100, TA102 and TA1530. All nine hydrazines were mutagenic in at least one tester strain, although of borderline significance for some of the compounds. The mutagenic potencies of the hydrazines varied 2-3 orders of magnitude, from very weak to moderate mutagenic activity. In general, the addition of S9 resulted in a lowering of the mutagenic activity and a lowering of the toxic properties of the hydrazines. The test results were relatively difficult to evaluate due to toxic effects of many of the test compounds on the test bacteria which may have resulted in an underestimation of the mutagenic potencies of some of the compounds. The pattern of mutagenic activity of the hydrazines in the different tester strains indicates that more than one mechanism of action may be involved in the mutagenicity.

Animals↗
PubMed1992

Manganese-mediated oxidative damage of cellular and isolated DNA by isoniazid and related hydrazines: non-Fenton-type hydroxyl radical formation.

The mechanism by which hydrazines induce damage to cellular and isolated DNA in the presence of metal ions has been investigated by pulsed-field gel electrophoresis (PFGE), DNA sequencing methods, and the ESR spin-trapping technique. For the detection of single-strand breaks by PFGE, an experimental procedure with alkali treatment has been designed. Isoniazid, hydrazine, and phenylhydrazine induced DNA single- and double-strand breaks in cells pretreated with Mn(II), whereas iproniazid did not. With isolated 32P-DNA, isoniazid produced DNA damage in the presence of Cu(II), Mn(II), or Mn(III). Iproniazid damage isolated DNA only in the presence of Cu(II). The Cu(II)-mediated DNA damage by isoniazid or iproniazid is due to active oxygen species other than hydroxyl free radical (.OH), presumably the Cu(I)-peroxide complex. Cleavage of isolated DNA by isoniazid plus Mn(II) occurred without marked site specificity. The DNA damage was inhibited by .OH scavengers and superoxide dismutase (SOD) but not by catalase, suggesting the involvement of .OH formed via O2- but not via H2O2. Consistently, in ESR experiments .OH formation was observed during Mn(II)-catalyzed autoxidation of isoniazid, and the .OH formation was inhibited by SOD, but not by catalase. Iproniazid plus Mn(II) produced no or little .OH. We propose a reaction mechanism for the .OH formation without a H2O2 intermediate during manganese-catalyzed autoxidation of hydrazine. The present and previous data raise the possibility that hydrazines plus Mn(II)-induced cellular DNA damage may occur, at least in part, through the non-Fenton-type reaction.

Autoradiography↗