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PubMed1983

Autonomic-cardiovascular dysfunction accompanies sensory-motor impairment during acrylamide intoxication.

We investigated the effects of acrylamide monomer on autonomic-cardiovascular functions and simple sensory-motor behaviors. Rats were intoxicated by ip injections of acrylamide at a dose of 50 mg/kg/day for 10 days; control animals received an equivalent volume of saline. Heart rate (HR) and systolic arterial blood pressure (BP) were measured using the method of indirect tail plethysmography. Intoxicated animals showed fluctuating but significant increases in HR and BP after the first dose of acrylamide, during the course of the intoxication, and two days after the last dose. Deficits in sensory-motor behaviors appeared after the first dose of acrylamide and progressed steadily throughout the exposure period, remaining two days after the last dose. More complex sensory-motor behaviors were affected earliest; hindlimb functions were affected before forelimb functions, characteristic of dying-back axonopathy. These results demonstrate that acrylamide alters common measures of autonomic-cardiovascular functioning in addition to simple sensory-motor behaviors.

Acrylamides↗

PubMed1982

Postsynaptic location of acrylamide-induced modulation of striatal 3H-spiroperidol binding.

The striata of rats were unilaterally lesioned with kainic acid. After two weeks, rats were exposed to 10 doses of acrylamide (20 mg/kg body weight/dose) over two weeks. Binding of 3H-spiroperidol to membranes prepared from unoperated striata, was elevated in acrylamide-exposed rats relative to undosed controls. This differential was not apparent when binding was compared in membranes from kainate-treated striata of acrylamide-treated and untreated rats. A parallel acrylamide treatment of unoperated rats had no significant effect on striatal levels of dihydroxyphenylacetic acid and homovanillic acid suggesting that this neurotoxicant failed to affect the presynaptic events of the dopamine system. Thus, the alterations of the striatal dopamine receptor caused by acrylamide, that have been previously reported, appear to be confined to postsynaptic sites.

Acrylamides↗

PubMed1982

The effects of acrylamide on the behavioral suppression produced by psychoactive agents.

Rats were trained to lever touch for food on a Variable Interval (VI) 15 sec. schedule of reinforcement. Dose-response alteration of VI responding by apomorphine, d-amphetamine, clonidine, and chlordiazepoxide was studied along and in the presence of a dose of acrylamide which, by itself, did not alter VI responding. Pretreatment with 12.5 mg/kg of acrylamide 24 hrs. prior to challenge with psychoactive compounds enhanced the behavioral suppressant effects of apomorphine and d-amphetamine. No significant effect of acrylamide pretreatment on the behavioral effects of clonidine and chlordiazepoxide was observed. These data suggest that acute exposure to acrylamide increases responsiveness to agents that act directly on dopamine (DA) receptors or indirectly by releasing DA. This change in responsiveness to apomorphine and d-amphetamine may be related to the effects of acrylamide on the affinity or density of the DA receptor.

Acrylamides↗

PubMed2007

Modification of HTPB-based polyurethane with temperature-sensitive poly(N-isopropyl acrylamide) for biomaterial usage.

Hydroxyl-terminated polybutadiene (HTPB)-based polyurethane with dimethyol propionic acid (DPA) as chain extender was synthesized by solution polymerization. The HTPB-based polyurethane was modified by UV radiation with N-isopropyl acrylamide monomer to get poly(N-isopropyl acrylamide)-modified polyurethane (PUDPANIPAAm). The cohesive energy (E(coh)), molar volume (V), solubility parameter (delta), molecular weight (W(M)), volume per gram (V(g)), and the density (1/V(g)) of PUDPANIPAAm were calculated by group contribution methods. To evaluate the application of PUDPANIPAAm for wound dressing and transplantation of cell sheet, the measurement of water content, water vapor transmission rate, and gas permeation on the PUDPANIPAAm membrane was evaluated. The biocompatibility of these membranes, cell adhesion, and proliferation assay were conducted in the cell culture. The effect of thermosensitivity of poly(N-isopropyl acrylamide) on cell detachment was also evaluated in the primary study. The results showed that these PUDPANIPAAm membranes are thermosensitive. The modification of PU with poly(N-isopropyl acrylamide) reduced the water vapor transmission rate and permeability of gas through PUDPANIPAAm membrane. PUDPANIPAAm membranes could support cell adhesion and growth. Owing to the thermosensitive nature of poly(N-isopropyl acrylamide), the relative cell numbers detached from PUDPANIPAAm membranes were larger than those detached from the polystyrene dish.

3T3 Cells↗

PubMed2006

Incorporation of substituted acrylamides to the lamellar mesophase of Aerosol OT.

The structure and stability of the lamellar liquid crystal formed by the surfactant sodium bis-2ethylhexyl sulfosuccinate (AOT) in water is perturbed by small amounts of the substituted acrylamides N-isopropyl, N,N-diethyl, N-acryloylmorpholine, and N,N-dimethyl methacrylamide, as revealed by small angle X-ray scattering (SAXS), deuterium NMR, and microscopy. These molecules are water soluble and stay mostly in the water layers between lamellae, but a small fraction of them (5-19%) are incorporated into the AOT bilayers, thereby producing dramatic changes. Both, the degree of anisotropy in the water molecules hydrating AOT (quadrupolar splitting in (2)H NMR) and the long period spacing between lamellae (SAXS), decrease with addition of this molecules at low concentrations, which is attributed to the lower average headgroup density at the AOT/water interface when the acrylamide is incorporated. The strength of these perturbations depends on the acrylamide, and goes in parallel with the hydrophobic character of the alkyl side groups in its molecule, which suggests that the acrylamides incorporated to the bilayer enter into contact with the lipophilic tails of the AOT molecule. An interaction with the hydrated heads of AOT is also suggested in the particular case of N-isopropylacrylamide. On increasing the molecule concentration an incipient melting of the lamellar phase towards an isotropic solution takes place, first at the microscopic level, then macroscopic. Near this phase transition, the ordered domains lose the random orientation prevailing at lower acrylamide concentrations, and adopt a preferred orientation, perpendicular to the magnetic field.

Journal Article↗

PubMed1992

Preincubation with cysteine prevents modification of sulfhydryl groups in proteins by unreacted acrylamide in a gel.

It has been found that the double bond of free, unreacted acrylamide in a gel can react with a free -SH group of proteins, forming a cysteinyl-S-propionamide adduct. When beta-lactoglobulin was incubated at concentration levels lower than those of free acrylamide, left after polymerizing a 5% T, 4% C gel (barely 12 mM), under anaerobic conditions in 0.1 M borate, pH 9.5, for 1 h and then the tryptic digests analyzed by high performance liquid chromatography (HPLC), two new peptides were detected. The two new peaks were recovered and sequenced by the Edman degradation procedure. They correspond to the sequence from Leu-149 to Ile-162. Residue No. 160 was found to be a cysteinyl-S-propionamide reaction product. Interestingly, only this residue, out of a total of 5 Cys residues, had reacted. No other amino acids (including -NH2 terminus and free -NH2 in Lys) reacted with free acrylamide. The addition of free acrylamide to the -SH group could be completely inhibited if: (i) the gel was extensively washed prior to sample application, or (ii) the gel was incubated for 1 h in 100 mM free Cys.

Acrylamide↗

PubMed1987

Mutagenicity and clastogenicity of acrylamide in L5178Y mouse lymphoma cells.

Acrylamide was tested without exogenous activation in L5178Y/TK+/- -3.7.2C cells for mutation at the thymidine kinase locus and for clastogenicity. Acrylamide gave a positive induced mutagenic response (approximately 70 mutants/10(6) survivors) when tested at 600-650 micrograms/ml. The highest dose tested (850 micrograms/ml) resulted in an induced mutant frequency of approximately 380 mutants/10(6) survivors (survival = 13%). Acrylamide induced almost exclusively small-colony mutants, indicating that it might be acting by a clastogenic mechanism. As predicted, acrylamide was clastogenic, inducing both chromatid and chromosome breaks and rearrangements. A clearly positive clastogenic response was observed at both the 750 micrograms/ml and 850 micrograms/ml doses, which showed 16 and 64 aberrations per 100 cells, respectively (background = 3 aberrations per 100 cells). These studies indicate that the L5178Y/TK+/- mouse lymphoma assay can detect some chromosomal mutagens (clastogens) that show little activity in other single gene mutation assays, the CHO/HPRT and Salmonella.

Acrylamide↗

PubMed1995

Toxicokinetics of a single 50 mg/kg oral dose of [2,3-14C]acrylamide in White Leghorn hens.

A single oral dose of [2,3-14C]acrylamide (50 mg/kg) was administered in water to adult white leghorn hens. Seven groups of three hens were euthanized between 2 and 120 hr after administration. Within 12 hr, the hens excreted 70% of the administered dose, and more than 99% within 48 hr. Blood, plasma, liver, and muscle contained the greatest percentage of administered dose at 4 hr after dosing. Less than 0.02% of the administered dose appeared in brain at any time. Radiolabel accumulated in the eggs, with 0.52% of the administered dose accumulated within 5 days. Binding of radiolabel to erythrocytes was minimal. Elimination of radiolabel from all tissues was biphasic. Terminal elimination half-lives for 14C were longer than 10 days, at which time less than 0.2% of the administered dose remains in the tissues. Distribution half-lives for 14C were longest for whole blood and shortest for kidney. Radioactivity in the blood and plasma reached a peak at between 4 and 12 hr. Most of this radioactivity was identified as acrylamide, which disappeared biexponentially with terminal elimination half-lives longer than 10 days. Distribution half-lives for acrylamide were longest in brain and shortest in whole blood. These results show that orally administered acrylamide is poorly absorbed and rapidly eliminated from hens and accumulates in their eggs in a nonextractable form.

Acrylamide↗

PubMed2005

Mechanistic pathways of formation of acrylamide from different amino acids.

Studies on model systems of amino acids and sugars have indicated that acrylamide can be generated from asparagine or from amino acids that can produce acrylic acid either directly such as beta-alanine, aspartic acid and carnosine or indirectly such as cysteine and serine. The main pathway specifically involves asparagine and produces acrylamide directly after a sugar-assisted decarboxylation and 1,2-elimination steps and the second non-specific pathway involves the initial formation of acrylic acid from different sources and its subsequent interaction with ammonia to produce acrylamide. Aspartic acid, beta-alanine and carnosine were found to follow acrylic acid pathway. Labeling studies with [13C-4]aspartic acid have confirmed the occurrence in aspartic acid model system, of a previously proposed sugar-assisted decarboxylation mechanism identified in asparagine model systems. In addition, creatine was found to be a good source of methylamine and was responsible for the formation of N-methylacrylamide in model systems through acrylic acid pathway. Furthermore, certain amino acids such as serine and cysteine were found to generate pyruvic acid that can be converted into acrylic acid and generate acrylamide when reacted with ammonia.

Acrylamide↗

PubMed2005

Chemical intervention strategies for substantial suppression of acrylamide formation in fried potato products.

Prototype processes were developed for the substantial suppression of acrylamide formation (40-95% compared to untreated controls) in cut surface fried potato products using potato chips (crisps) as the primary model. The most efficacious procedures employed sequentially both surface preparation and subsequent acrylamide precursor complexation and/or competitive inhibition processing steps. Surface preparation processing involved either various low-temperature (50-75 degrees C) aqueous (5-30 min) or ca. 80% ethanol blanch solutions for various times (1-5 min) combined with aqueous leaching steps (1-10 min) to reduce concentration of acrylamide precursors in the critical frying zone of cut potato surfaces. Acrylamide precursor complexation and/or competitive inhibition processing strategies included immersion exposure of prepared cut potato surfaces to solutions or dispersions of various combinations of either calcium chloride, phytic acid, chitosan, sodium acid pyrophosphate, or N-acetylcysteine.

Acrylamide↗

PubMed1991

Heterogeneous visceral nerve changes in acrylamide intoxication.

A variety of visceral nerves were studied by intermediate filament immunocytochemistry in rats intoxicated with acrylamide. In such animals, oesophageal and diaphragmatic motor end-plates were invaded and deformed by neurofilament protein-like material, while afferent fibres of diaphragmatic neuromuscular spindles and myelinated sensory fibres of the iris showed striking terminal accumulation of similar material. Conversely, the rich population of thin afferent fibres of the iris showed no obvious abnormality, while pre-terminal changes were seen along the extrinsic nerve fibres supplying the cornea and myenteric ganglia. Multiple lesions were demonstrated in gut nerves of acrylamide-treated rats, while scattered "enteric glial cells" showed abnormally coarse morphology and a striking increase in glial fibrillary acidic protein immunoreactivity. A distinct, delicately varicose appearance was revealed by neurofilament protein-immunostaining in bladder nerve fibres of normal rats, which was changed to one of coarse dilations by acrylamide. In conclusion, apparently selective changes were found along different types of axons, indicating marked heterogeneity in cytoskeletal organisation among visceral nerves. Taken together with the proposed inhibition by acrylamide of neurofilament proteins degradation, the above findings may suggest a non-uniform distribution of neurofilament degradation sites along distal regions of different axons.

Acrylamide↗

PubMed1984

Peripheral nerve phospholipids in acrylamide neuropathy.

Treatment of cats with acrylamide, either 7.5 or 15 mg/kg IM, once a day for 10 days, resulted in increases of 31 and 47% in the phospholipid content of sciatic nerve, respectively, from a control level of 41.1 +/- 2.7 mg/kg wet weight. Determination of the distribution of individual phospholipids indicated no significant differences between control cats and those receiving a cumulative dose of 150 mg/kg acrylamide. In a separate experiment, cats were treated with the 150 mg/kg dose of acrylamide and the sciatic nerve was divided into proximal and distal portions at the level of the triceps surae nerve. Significant increases in phospholipid content were observed in both the proximal and distal portions of peripheral nerve of the acrylamide-intoxicated cats. This effect was present even when the phospholipid content was expressed in terms of total protein, dry weight or total lipid. Total weight of nerve segments, however, was significantly decreased in the neuropathic animals. The data are consistent with a focal degeneration of axons with relative sparing of phospholipids.

Acrylamide↗

PubMed1986

Quenching by acrylamide and temperature of a fluorescent probe attached to the active site of ribonuclease.

The fluorescence properties of ribonuclease labelled at its active site with N-(iodoacetylamino)-ethyl-5-naphthylamine-1-sulfonic acid have been studied at different temperatures and in the presence of acrylamide. The rate constant for the quenching of the fluorescence of labelled ribonuclease by acrylamide is apparently not limited by the "accessibility" of the probe: similar values are obtained for the native and denatured states of the protein. Instead, acrylamide seems to be a rather inefficient quencher of this fluorescent group [acetamidoamino)ethyl-5-naphthylamine-1-sulfonic acid), as shown by non-linear Stern-Volmer representations, biphasic decay kinetics, and a low value of the rate constant. The fluorescence intensity of the native state of the labelled protein is highly sensitive to temperature and exhibits a 20% decrease for an increase of temperature of from 10 degrees C to 30 degrees C, independent of solvent viscosity. This thermal quenching is specific for the native conformation and disappears when the protein is unfolded. When the fluorescence lifetime of the label is shortened by addition of acrylamide, the effect of temperature becomes identical for native and unfolded structures. This suggests that the cause of the thermal quenching is the presence of conformational fluctuations within the native protein which apparently take place in the time range from 35 to 200 ns.

Acrylamide↗

PubMedDate not supplied

Acrylamide-induced alterations in axonal transport. Biochemical and autoradiographic studies.

Alterations in the axonal transport of proteins, glycoproteins, and gangliosides in sensory neurons of the sciatic nerve were examined in adult male rats exposed to acrylamide (40 mg ip/kg body wt/d for nine consecutive days). Twenty-four hours after the last dose, the L5 dorsal root ganglion (DRG) was injected with either [35S]methionine to label proteins or [3H]glucosamine to label glycoproteins and gangliosides. The downflow patterns of radioactivity for [35S]methionine-labeled proteins and [3H]glucosamine-labeled gangliosides were unaltered by acrylamide treatment. In contrast, the outflow pattern of labeled glycoproteins displayed a severely attenuated crest with no alteration in velocity, suggesting a preferential transfer with the unlabeled stationary components in the axolemma. Retrograde accumulation of transported glycoproteins and gangliosides was unaltered for at least 6 h; however, by 24 h, there was a 75% decrease in the amount of accumulated material. The accumulation of [35S]methionine-labeled proteins was not altered. Autoradiographic analysis revealed an acrylamide-induced paucity of transported radiolabeled glycoproteins selectively in myelinated axons with no effect on "nonmyelinated" axons. The pattern of transported proteins was similar in both control and acrylamide-exposed animals. These results suggest a preferential inhibition of glycosylation or axonal transport of glycoproteins in neurons bearing myelinated axons. More importantly, it suggests that interpretations of axonal transport data must be made with the consideration of alterations in selective nerve fibers and not with the tacit assumption that all fibers in the nerve population are equally affected.

Acrylamide↗

PubMed1993

Effect of acrylamide on the distribution of microtubule-associated proteins (MAP1 and MAP2) in selected regions of rat brain.

The effect of acrylamide treatment on the immunocytochemical localization of microtubule-associated proteins (MAP1 and MAP2) was studied in different brain regions (cerebellum, cerebral cortex, and hippocampus) of adult rats. Animals were treated with acrylamide (estimated mean dose: 15 mg/kg/d) orally for 2 wk when they showed slight hindlimb weakness. Immunoreactivity for MAP1 and MAP2 was detected in tissue sections with monoclonal antibodies according to the Sternberger's peroxidase-antiperoxidase technique. Intense MAP1 immunoreactivity was observed in neuronal perikarya and dendrites, with faint staining in axons. By contrast, MAP2 immunostaining was selectively observed in dendrites and neuronal perikarya. Treatment of animals with acrylamide reduced immunoreactivity for both MAP1 and MAP2 in hippocampus and cerebellum, with relatively little change in cerebral cortex. Loss of MAPs immunoreactivity in affected brain areas likely proceeded from dendrite to perikaryon. The results of this study indicate that hippocampal compromise is part of the neurotoxic picture associated with rodent exposure to acrylamide.

Acrylamide↗

PubMed1992

Alkylation of cysteine with acrylamide for protein sequence analysis.

Alkylation of cysteine in proteins with acrylamide under mildly alkaline conditions yields a thioether derivative, Cys-S-beta-propionamide (Cys-S-Pam), which is stable during automated Edman degradation. Its phenylthiohydantoin derivative, PTH-Cys-S-Pam, is easily separated from other PTH-amino acids by HPLC and is thus useful for cysteine identification during protein sequencing. PTH-Cys-S-Pam was first noticed during sequencing polypeptides blotted onto polyvinylidene difluoride membranes from polyacrylamide gels, in which cysteine had reacted with residual unpolymerized acrylamide. Cysteine in proteins is easily alkylated by reaction of proteins in aqueous solution with acrylamide. Methods are also presented for alkylation of cysteine in proteins adsorbed on fiberglass disks in the reaction cartridge of a protein sequencer. Finally, PTH-Cys-S-Pam was synthesized chemically. The synthetic compound is unstable in neutral solution, but can be stabilized by acidification. It has the same HPLC retention time as the product formed from cysteine when sequencing proteins alkylated with acrylamide.

Acrylamide↗

PubMed1985

Effects of mixed-function oxidase modifiers on neurotoxicity of acrylamide in rats.

The effects of modifiers of the microsomal mixed-function oxidase system on acrylamide-induced hind-limb paralysis were investigated in rats. Pretreatment of rats with phenobarbital, trans-stilbene oxide or dichloro diphenyl trichloroethane (DDT) resulted in an earlier onset and subsequent development of acrylamide-induced hind-limb paralysis than that observed in animals treated only with acrylamide. Cobalt chloride pretreatment of rats caused a significant delay in the onset and development of hind-limb paralysis. Our results suggest that an intermediate formed by the cytochrome P-450 system may be responsible for acrylamide neurotoxicity.

Acrylamide↗

PubMed1994

Cytoplasmic desmosomes and intermediate filament disturbance following acrylamide treatment in cultured rat keratinocytes.

The present paper describes disturbances in the organization of tonofilaments and desmosomes of rat lingual and epidermal keratinocytes after treatment of the cells with acrylamide in culture. This treatment induced changes in cell shape, reduction of intercellular adhesion and a perinuclear accumulation of cytoplasmic organelles. Using specific antibodies for cytokeratins, the filaments were disorganized particularly in the perinuclear region. In untreated cells, keratin filament labelling was very weak or absent above and below the nucleus thus leaving a black nuclear space in fluorescine microscopy. Following acrylamide treatment, the keratin filament labelling covered the nuclear space which indicated the accumulation of these filaments all around the nucleus. Furthermore, the desmosomal junctions were often associated with thick keratin bundles. Antibodies for desmoplakins revealed a reduction in intercellular labelling and stronger cytoplasmic labelling. Ultrastructurally, well-developed long tonofilaments were found to associate with large desmosomal junctions. Furthermore, small-sized desmosomal structures were identified within the cytoplasm. Morphologically, these were identical to cell surface desmosomes and were almost always associated with well-developed tonofilaments. The effect of acrylamide on the protein kinase A activity might be implicated in the disturbances of the desmosome-intermediate filament complex and in the initiation of contractile forces necessary for perinuclear accumulation of intermediate filaments and for the formation of intact cytoplasmic desmosomes. The acrylamide-induced intermediate filament and desmosomal changes may provide valuable information on the mechanism of intact cytoplasmic desmosome formation in several skin diseases and in squamous cell carcinoma.

Acrylamide↗