Protective mechanism of quercetin compounds against acrylamide-induced hepatotoxicity

Quercetin compounds have antioxidant,anti-inflammatory and anticancer pharmacological functions.Longterm exposure to acrylamide(AA)can cause liver injury and endanger human health.However,whether quercetin compounds can attenuate AA-induced liver injury and the specific mechanism are not clear.Here,we studied the mechanism and structure-activity relationship of quercetin compounds in reducing AA-induced hepatotoxicity in vivo and in vitro.In vivo studies found that quercetin-like compounds protect against AAinduced liver injury by reducing oxidative stress levels,activating the Akt/m TOR signaling pathway to attenuate autophagy,and improving mitochondrial apoptosis and endoplasmic reticulum stress-mediated apoptosis.In vitro studies found that quercetin compounds protected Hep G2 cells from AA by attenuating the activation of AA-induced autophagy,lowering reactive oxygen species(ROS)levels by exerting antioxidant effects and thus attenuating oxidative stress,increasing mitochondrial membrane potential(MMP),and improving apoptosis-related proteins,thus attenuating AA-induced apoptosis.Furthermore,the conformational differences between quercetin compounds correlated with their protective capacity against AA-induced hepatotoxicity,with quercetin showing the best protective capacity due to its strongest antioxidant activity.In conclusion,quercetin compounds can protect against AA-induced liver injury through multiple pathways of oxidative stress,autophagy and apoptosis,and their protective capacity correlates with antioxidant activity.

Procyanidin A_1 and its digestive products alleviate acrylamide-induced IPEC-J2 cell damage through regulating Keap1/Nrf2 pathway

Our previous study has revealed that procyanidin A_(1)(A_(1))and its simulated digestive product(D-A,)can alleviate acrylamide(ACR)-induced intestine cell damage.However,the underlying mechanism remains unknown.In this study,we elucidated the molecular mechanism for and D-A_(1) to alleviate ACR-stimulated IPEC-J2 cell damage.ACR slightly activated nuclear factor erythroid 2-related factor 2(Nrf2)signaling and its target genes,but this activation could not reduce intestine cell damage.A_(1) and D-A_(1) could alleviate ACR-induced cell damage,but the effect was abrogated in cells transiently transfected with Nrf2 small interfering RNA(siRNA).Further investigation confirmed that A_(1) and D-A_(1) interacted with Ketch-like ECH-associated protein 1(Keapl),which boosted the stabilization of Nrf2,subsequently promoted the translocation of Nrf2 into the nucleus,and further increased the expression of antioxidant proteins,thereby inhibiting glutathione(GSH)consumption,maintaining redox balance and eventually alleviating ACR-induced cell damage.Importantly,there was no difference between A_(1) and D-A_(1) treated groups,indicating that A_(1) can tolerate gastrointestinal digestion and may be a potential compound to limit the toxicity of ACR.

ZnO Incorporated Acrylamide Grafted Chitosan Based Composite Film for Advanced Wound Healing Applications

This study was carried out to prepare ZnO nanoparticles incorporated acrylamide grafted chitosan composite film for possible biomedical application especially drug loading in wound healing. ZnO nanoparticles were prepared by co-precipitation method from zinc acetate di-hydrate and incorporated in acrylamide grafted chitosan. FT-IR and TGA of the prepared composite film confirmed the successful incorporation of ZnO nanoparticles in the acrylamide-grafted polymer matrix. SEM images showed that the ZnO nanoparticles were homogeneously distributed on the porous matrix of the composite film. Water uptake and buffer uptake analysis revealed that the composite film could hold water and buffer sufficiently, which facilitated the absorption of exudate from the wound site. Amoxicillin was loaded in the prepared composite film and the maximum loading efficiency was found to be 67.33% with drug concentration of 300 ppm. In vitro studies showed greater antimicrobial activity of drug-loaded composite film compared to both pure film and standard antibiotic disc. Finally, the In vivo mouse model showed maximum healing efficiency compared to conventional gauge bandages because the loading of antibiotic in the film produced a synergistic effect and healing time was reduced.

Melatonin alleviates oxidative stress,inflammation,apoptosis,and DNA damage in acrylamide-induced nephrotoxicity in rats

Objective:To investigate the effects of melatonin on renal inflammation,oxidative stress,apoptosis,as well as DNA and tissue damage in acrylamide-induced nephrotoxicity in rats.Methods:Fifty male rats were randomly divided into five groups.The control group received distilled water by gastric lavage for 11days and the acrylamide group was administered acrylamide(50 mg/kg,i.g.)for 11 days.The MEL10+ACR and MEL20+ACR groups received intraperitoneal melatonin 10 and 20 mg/kg,respectively,for 11 days,and acrylamide(50 mg/kg,i.g.)was administered 1h after melatonin injection.The MEL20 group was injected with melatonin(20 mg/kg)for 11 days.Kidney function tests were performed and biochemical and inflammatory parameters were determined.In addition,histopathological,immunohistochemical,and immunofluorescence examinations were carried out.Results:Melatonin significantly abated acrylamide-induced rise in serum urea and creatinine levels.Acrylamide caused oxidative stress,inflammation,apoptosis,as well as DNA and tissue damage in the kidneys.Melatonin treatment alleviated acrylamide-induced renal damage by exhibiting antioxidant,anti-inflammatory,and antiapoptotic effects.Moreover,melatonin significantly ameliorated acrylamide-caused histopathological changes in kidney tissue.Conclusions:Melatonin attenuates acrylamide-induced renal oxidative stress,inflammation,apoptosis,and DNA damage in rats.

Synthesis and Flocculation Property of Chitosan-Acrylamide Graft Copolymer

Chitosan, as a kind of natural polymer, has many advantages, such as abundant sources, biological degradation, no secondary contamination and facile modification. In this work, we prepared modified chitosan flocculants with double electrical behavior via polymerizing chitosan, acrylamide and sodium carboxymethyl cellulose together by using ammonium persulfate as the indicator in water. The product is a comb-type of chitosan copolymer and a polymeric ampholyte. And then we studied the product by FTIR, UV-Vis, TG, DSC spectrometeries and viscometry, etc. We also performed CACM′s water treat experiment. The effects of pH values, reaction time and dose of the new floccalant on treating various of waste water have been investigated, too.

Dietary Exposure of the Chinese Population to Acrylamide

Objective To assess the current status of the acrylamide in the Chinese food supply, the dietary acrylamide exposure in the Chinese population and to estimate the public health risks of the current consumption. Methods The acrylamide content in the total diet study （TDS） food samples was analyzed using an LC-MS/MS method. Based on the analytical results, the dietary exposure calculations were performed using a deterministic method, combining mean acrylamide concentrations from the food group composite with their associated food consumptions. Results Acrylamide was detected in 43.7% of all samples collected and acrylamide concentration varied from ND to 526.6 I^g/kg. The estimated dietary intakes of acrylamide among Chinese general population given as the mean and the 95th percentile （P95） were 0.286 and 0.490 iJg.kg1 bw.day1, respectively. The margins of exposure （MOEs） for the population calculated using both benchmark dose lower confidence limit for a 10% extra risk of tumors in animals （BMDL10） 0.31 and 0.18 i^g.k8-1 bw-dayz, were 1069 and 621 for the mean dietary exposure, and 633 and 367 for the high dietary exposure respectively. Conclusion These MOE values might indicate a human health concern on acrylamide for Chinese population. Efforts should continue to reduce acrylamide levels in food in order to reduce the dietary risks to the human health.

SWELLING BEHAVIOR OF ACRYLAMIDE HYDROGEL IN DIFFERENT SOLVENTS AND pHs

Swelling property of acrylamide hydrogels,prepared from aqueous solutions of acrylamide monomer havingconcentrations in the range of 10-60 wt% by ray irradiation method using a Co-60 gamma radiation source at dosesranging 1-30.0 kGy,has been investigated under various swelling media.These swelling media were basically solvents(solutions),produced by dissolving methanol,ethanol,glucose,sucrose,sodium chloride and sodium persulfate individuallywith distilled water,and solutions prepared with pHs=3,7 and 10.The investigation was performed in order to observe theeffect of these solvents and pHs as well as the influence of monomer concentrations,radiation doses and times on swellingbehavior of hydrogels.Swelling values were found higher for hydrogels prepared with lower monomer concentrations(ca.20 wt%)and radiation doses(ca.5 kGy)and showed a leveling off tendency within 24 h.The glucose solvent and the buffersolution of pH=10 revealed significant increase of swelling of hydrogels as compared to other solutions.Results areexplained based on crosslinking density in hydrogel,polymer-solvent/polymer-polymer interactions in solutions,permeability of molecules in solutions and ionization capacity of hydrogel in pH.

Immunotoxicity of Acrylamide in Female BALB/c Mice

Objective To investigate the immunotoxicity of acrylamide （ACR） in female BALB/c mice.Methods A total of 200 female mice weighing 18-22 g were randomly divided into four clusters based on body weight, and each weight-based cluster included five groups （10 mice per group）： negative control, positive control （cyclophosphamide）, low, intermediate, and high dose ACR groups, and all the groups were administered ACR by gavage for 30 days. At the end of the study, the immunotoxicological effects of the ACR were evaluated through immunopathology, humoral immunity, cellular immunity, and non-specific immunity. Results The terminal body weight, spleen and thymus weights, lymphocyte counts in the ACR-H group were decreased, pathological changes were observed in lymph glands, thymus and spleen. %T cells in blood lymphocytes were significantly increased in all ACR-treated groups, and a significant reduction of % natural killer（NK） cells and increase of %Th cells were observed in the ACR-H group. interleukin-6（IL-6）, Concanavalin A（ConA）-induced splenocyte proliferation and serum half hemolysis value （HCso） were also significantly suppressed in the ACR-H group. Conclusion ACR elicited an inhibitory effect on cellular and humoral immunity of mice after 30 day feeding.

Studies on LCST of poly (N-isopropylacrylamide-co-acrylic acid-co-N-diacetone acrylamide)

Linear copolymers from N-isopropylacrylamide （NIPA）, acrylic acid （AA） and diacetone acrylamide （DAA） have been prepared. The effect of composition, ionic strength and pH on their lower critical solution temperature （LCST） has been investigated.

PHOTO-INDUCED GRAFT POLYMERIZATION OF ACRYLAMIDE ON POLYPROPYLENE MEMBRANE SURFACE IN THE PRESENCE OF DIBENZYL TRITHIOCARBONATE

Ultraviolet （UV）-induced graft polymerization of acrylamide （AAm） on polypropylene substrates was successfully conducted using dibenzyl trithiocarbonate （DBTTC） as photoinitiator. It was confirmed by chemical analysis and surface morphology observation with attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. A possible mechanism for this graft process was presented, which suggested that, under UV irradiation, the C： S bond in DBTTC could split and abstract a hydrogen from the polypropylene surface and a surface free radical was then formed, and initiated the graft polymerization of AAm.

Determination of Residual Acrylamide in Medical Polyacrylamide Hydrogel by High Performance Liquid Chromatography tandem Mass Spectroscopy

Objective To determine residual acrylamide in medical polyacrylamide hydrogel by high performance liquid chromatography tandem mass spectroscopy （HPLC-MS）. Methods After 13C3 labeled acrylamide was added, the sample was extracted with water and then cleaned up with ExtrelutTM 20. The polyacrylamide hydrogel sample and 20 clinical cases were analyzed by HPLC-MS/MS and isotope dilution quantifying technique in selected reaction monitoring （SRM） mode. Results Acrylamide was separated from polyacrylamide hydrogel. The concentration of acrylamide in polyacrylamide hydrogel ranged from 3.9×10^-9 to 3.1×10^- 8g/L in the 20 clinical cases. The peak area was favorable linear and the range was up to 3 000 μg/L. The recovery rate was 103.1% with a relative standard deviation （RSD） of 6.20%, when the mark level was 50 lag/L. Conelusion HPLC-MS is a rapid, accurate, and sensitive method for the determination of residual acrylamide in medical polyacrylamide hydrogel.

Extract of Ginkgo biloba promotes neuronal regeneration in the hippocampus after exposure to acrylamide

Previous studies have demonstrated a neuroprotective effect of extract of Ginkgo biloba against neuronal damage, but have mainly focused on antioxidation of extract of Ginkgo biloba. To date, limited studies have determined whether extrasct of Ginkgo biloba has a protective effect on neuronal damage. In the present study, acrylamide and 30, 60, and 120 mg/kg extract of Ginkgo biloba were administered for 4 weeks by gavage to establish mouse models. Our results showed that 30, 60, and 120 mg/kg extract of Ginkgo biloba effectively alleviated the abnormal gait of poisoned mice, and up-regulated protein expression levels of doublecortin（DCX）, brain-derived neurotrophic factor, and growth associated protein-43（GAP-43） in the hippocampus. Simultaneously, DCX-and GAP-43-immunoreactive cells increased. These findings suggest that extract of Ginkgo biloba can mitigate neurotoxicity induced by acrylamide, and thereby promote neuronal regeneration in the hippocampus of acrylamide-treated mice.

Research on the Graft Copolymerization of EH-lignin with acrylamide

Lignin isolated from enzymatic hydrolyzed corn-stalks (EH-lignin) is a renewable natural polymer noted for its versatility and applicability in a vari-ety of uses. Graft copolymerization of EH-lignin with acrylamide (AM) and the application of this copolymer as a flocculant in dye wastewater treatment were studied in this article. The influ-ences of some factors on yield of copolymer and the grafting ratio were investigated and the structure of EH-lignin/AM graft copolymer was characterized by FT-IR. According to the yield and the grafting ratio, the optimum conditions for graft copolymerization were as follows: initiator K2S2O8-Na2S2O3 with a quantity 3 wt% of EH-lignin, mass ratio of AM to EH-lignin was 2~3, reaction time 4h and temperature at 50℃. It was found that the absorption capacity of graft copolymer to two azo-dyes was enhanced with the increase of grafting ratio. Furthermore, the residue concen-tration of EH-lignin/AM graft copolymer remained in the supernatant after flocculation was much lower than that of pure EH-lignin.

Influence of acrylamide monomer addition to the acrylic denture-base resins on mechanical and physical properties

The aim of the study was to evaluate the effect of adding acrylamide monomer （AAm） on the characterization, flexural strength, flexural modulus and thermal degradation temperature of poly（methyl methacrylate） （PMMA） denture-base resins. Specimens （n= 10） were fabricated from a conventional heat-activated QC-20 （Qc-） and a microwave heat-activated Acron MC （Ac-） PMMA resins. Powder/ liquid ratio followed the manufacturer＇s instructions for the control groups （Qc-c and Ac-c） and for the copolymer groups, the resins were prepared with 5% （-5）, 10% （- 10）, 15% （- 15） and 20% （-20） acrylamide contents, according to the molecular weight ratio, respectively. The flexural strength and flexural modulus were measured by a three-point bending test. The data obtained were statistically analyzed by Kruskal-Wallis test （a=O.05） to determine significant differences between the groups, The chemical structures of the resins were characterized by the nuclear magnetic resonance spectroscopy. Thermal stabilities were determined by thermogravimetric analysis （TGA） with a heating rate of 10 ~C.min-1 from 35 ~C to 600 ~C. Control groups from both acrylic resins showed the lowest flexural strength values. Qc-15 showed significant increase in the flexural strength when compared to Qc-c （P〈O.01）. Ac-10 and Ac-15 showed significance when compared to Ac-c （P〈O.01）. Acrylamide incorporation increased the elastic modulus in Qc-10, Qc-15 and Qc-20 when compared to Qc-c （P〈0.01）. Also significant increase was observed in Ac-10, Ac-15 and Ac-20 copolymer groups when compared to Ac-c （P〈0.01）. According to the 1H-nuclear magnetic resonance （NMR） results, acrylamide copolymerization was confirmed in the experimental groups. TGA results showed that the thermal stability of PMMA is increased by the insertion of AAm.

Acrylamide-induced Subacute Neurotoxic Effects on the Cerebral Cortex and Cerebellum at the Synapse Level in Rats

Objective To investigate acrylamide （ACR）-induced subacute neurotoxic effects on the central nervous system （CNS） at the synapse level in rats. Methods Thirty-six Sprague Dawley （SD） rats were randomized into three groups, （1） a 30 mg/kg ACR-treated group, （2） a 50 mg/kg ACR-treated group, and （3） a normal saline （NS）-treated control group. Body weight and neurological changes were recorded each day. At the end of the test, cerebral cortex and cerebellum tissues were harvested and viewed using light and electron microscopy. Additionally, the expression of Synapsin I and P-Synapsin I in the cerebral cortex and cerebellum were investigated. Results The 50 mg/kg ACR-treated rats showed a significant reduction in body weight compared with untreated individuals （P 〈 0.05）. Rats exposed to ACR showed a significant increase in gait scores compared with the NS control group （P 〈 0.05）. Histological examination indicated neuronal structural damage in the 50 mg/kg ACR treatment group. The active zone distance （AZD） and the nearest neighbor distance （NND） of synaptic vesicles in the cerebral cortex and cerebellum were increased in both the 30 mg/kg and 50 mg/kg ACR treatment groups. The ratio of the distribution of synaptic vesicles in the readily releasable pool （RRP） was decreased. Furthermore, the expression levels of Synapsin I and P-Synapsin I in the cerebral cortex and cerebellum were decreased in both the 30 mg/kg and 50 mg/kg ACR treatment groups. Conclusion Subacute ACR exposure contributes to neuropathy in the rat CNS. Functional damage of synaptic proteins and vesicles may be a mechanism of ACR neurotoxicity.

Synthesis and characterization of Ce_(0.8)Sm_(0.2)O_(1.9) nanopowders using an acrylamide polymerization process

Ce0.8Sm0.2O1.9(SDC) nanopowders were synthesized by an acrylamide polymerization process.The XRD results showed that SDC powders prepared at 700 °C possessed a cubic fluorite structure.Transmission electron microscopy(TEM) indicated that the particle sizes of powders were in the range of 10-15 nm.A 98.3% of theoretical density was obtained when the SDC pellets were sintered at 1350 °C for 5 h,indicating that the powders had good sinterability.The conductivity of the sintered SDC ceramics was 0.019 S/cm at 6...

Acrylamide exposure impairs blood-cerebrospinal fluid barrier function

Previous studies show that chronic acrylamide exposure leads to central and peripheral neu- ropathy. However, the underlying mechanisms remained unclear. In this study, we examined the permeability of the blood-cerebrospinal fluid barrier, and its ability to secrete transthyretin and transport leptin of rats exposed to acrylamide for 7, 14, 21 or 28 days. Transthyretin levels in cerebrospinal fluid began to decline on day 7 after acrylamide exposure. The sodium fluorescein level in cerebrospinal fluid was increased on day 14 after exposure. Evans blue concentration in cerebrospinal fluid was increased and the cerebrospinal fluid/serum leptin ratio was decreased on days 21 and 28 after exposure. In comparison, the cerebrospinal fluid/serum albumin ratio was increased on day 28 after exposure. Our findings show that acrylamide exposure damages the blood-cerebrospinal fluid barrier and impairs secretory and transport functions. These changes may underlie acrylamide-induced neurotoxicity.

OPTIMIZATION OF THE SYNTHESIS OF ACRYLAMIDE HYDROGEL BY γ-RAY IRRADIATION

Hydrogels have been synthesized from 10%, 20%, 30%, 40%, 50% and 60% aqueous solutions of acrylamide monomer by gamma radiation employing doses in the range of 0.2-30 kGy from a Co-60 source. The effect of solution concentration, γ-ray dose, pH and time was studied in order to observe the optimizing conditions in the characterization of hydrogels. Gel fraction increases with dose for all concentrations indicating hundred-percentage conversion of gel at doses 5 kGy for homogenous solutions in the range of 20%-50% concentration. On the other hand, 10% solution provides conversion less than 86% even at 30 kGy, whereas 60% monomer makes an inhomogeneous solution which stile gives about 100% gel fraction. Swelling of hydrogels under water with respect to time varies with both the doses and concentrations due to the change of crosslinking density in the gels. The maximum volume change of hydrogels during swelling and water desorption mainly occurs within 24 h. Swelling is also enhanced with the rise of pH due to change of ionic content of the solvent. Considering the amount of gel fraction and the properties of hydrogel, the samples prepared from 20% solution at 5 kGy show better results. Moreover, the effect of bacteria on hydrogel was found to be nil, suggesting a prohibition of growth of microorganism in it.

Radiation graft of acrylamide onto polyethylene separators for lithium-ion batteries

To improve the affinity between separators and electrolyte in lithium-ion battery,microporous polyethylene(PE) separator was grafted of polyacrylamide(PAAm) by radiation.Chemical structure of the PAAmgrafted PE separators(denoted as PE-g-PAAm) was characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.Properties of the pristine PE and PE-g-PAAm were tested by scanning electron microscope,liquid electrolyte uptake and lithium-ion conductivity.Electrochemical performances of the grafted PE separators(up to 0.76 × 10^(-3) S/cm of ionic conductivity at room temperature) were much better than pristine PE,and performance of the battery with the grafted separator behaved better than with the virgin PE separator,under the same condition(assembled in Ar-filled glove box).

Preparation of Nanocrystalline Tin Dioxide Particles via the Acrylamide Polymerization Process

We report simple acrylamide polymerization process to prepare nanocrystalline tin dioxide(SnO_2) particles.A small amount of the so-called premix solution(monofunctional acrylamide and difunctional N,N'-methylenebisacrylamide) was mixed with the aqueous solution of Sn^(4+) in certain proportion,and a few drops of ammonium persulfate solution were added as initiator.When homogenized by magnetic stirring and heated to about 70℃,the mixed solution became a gel.This hydrous gel was directly decomposed by thermal treatment,resulting in obtaining rutile crystalline SnO_2 particles with a narrow size distribution typically in the range of 20 nm～40 nm.