scholarly journals Acrylamide reduces plasma antioxidant vitamin levels in rats due to increased oxidative damage

2020 ◽  
Vol 33 ◽  
Author(s):  
Yeşim YENER ◽  
Fatma Hümeyra YERLİKAYA

ABSTRACT Objective Acrylamide is a potentially neurotoxic and carcinogenic chemical and naturally creates during the heating process of carbohydrate-rich foods, such as potato chips and breakfast cereals. Acrylamide might be ingested by people via consuming food that contains it. Therefore, we investigated the effect of acrylamidegiven orally to male and female rats on plasma retinoic acid and α-tocopherol and serum sialic acid and malondialdehyde levels. Method A total of 50 Wistar rats were used (25 female and 25 male, three-four weeks old). The rats of each sex were given 2 and 5mg/kg/day acrylamide via drinking water for 90 days. At the end of the treatment, the animals were euthanized by cervical dislocation. Blood specimens were collected through cardiac puncture, and serum and plasma samples were analysed using the high-performance liquid chromatography technique with a Ultraviolet detector. Results The analysis of the plasma and serum samples revealed that serum sialic acid and malondialdehyde levels in both sexes given 5mg/kg/day acrylamide were significantly increased, and the serum sialic acid levels were higher in female rats given 2mg/kg/day acrylamide. The plasma retinoic acid and α-tocopherol levels significantly decreased in both sexes given only the highest dose. Conclusion The results show that acrylamide causes an increase in oxidative stress and leads to a decrease in the levels of retinoic acid and α-tocopherol which play a role in the defense mechanism against this stress.

Biomolecules ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 459 ◽  
Author(s):  
Graham Brogden ◽  
Diab M. Husein ◽  
Pablo Steinberg ◽  
Hassan Y. Naim

Sphingolipids are an important group of lipids that play crucial roles in living cells, facilitating cell recognition, signal transduction and endocytosis. The concentration of sphingosine and some of its derivatives like sphinganine may serve as a biomarker for the diagnosis of sphingolipidoses or be used for further research into similar diseases. In this study, a sphingolipid extraction and a high resolution detection method specific for sphingosine and sphinganine was adapted and tested. Lipids were extracted from rats’ serum, coupled to o-phthalaldehyde and detected with a fluorescence detector after running through a silica gel column in a high performance liquid chromatography system. With this method, we analysed 20 male and 20 female rat serum samples and compared the concentrations of sphingosine and sphinganine. The results showed a significant difference between the sphingosine concentrations in the male and female rats. The sphingosine concentration in female rats was 805 ng/mL (standard deviation, SD ± 549), while that in males was significantly lower at (75 ng/mL (SD ± 40)). Furthermore, the sphingosine:sphinganine ratio was almost 15-fold higher in the females’ samples. The method presented here facilitates the accurate quantification of sphingosine and sphinganine concentrations down to 2.6 ng and 3.0 ng, respectively, and their ratio in small amounts of rat serum samples to study the sphingolipid metabolism and its potential modulation due to gene mutations or the effect of prevalent toxins.


1983 ◽  
Vol 64 (1) ◽  
pp. 85-90 ◽  
Author(s):  
Maurizio Muraca ◽  
Jan De Groote ◽  
Johan Fevery

1. Hepatic bilirubin UDP-glucuronosyltransferase activity was higher in female than in male rats; gonadectomy decreased enzyme activity in females and increased it in males. This sex difference in bilirubin conjugation was further used to evaluate the effect of differences in conjugation on the maximal biliary excretion of bilirubin in the non-anaesthetized rat. 2. After infusion of bilirubin, the maximal biliary excretory rate (Tm) and maximal concentration of bilirubin in bile were respectively 70% and 40% higher in female than in male rats; these values were decreased in females after ovariectomy and increased in males after orchiectomy. A linear relationship was found (r = 0.86; P < 0.001) between bilirubin Tm and hepatic bilirubin UDP-glucuronosyltransferase activity in the four groups of rats, suggesting that conjugation was the rate-limiting step for the maximal hepatic transport of bilirubin. 3. At the end of bilirubin infusion, bilirubin conjugates in serum, determined by alkaline methanolysis and high-performance liquid chromatography, ranged from 0.5 to 1.4% of total bilirubin. Therefore no significant reflux of conjugated bilirubin occurred during saturation of the hepatic transport of the pigment, once more suggesting that the secretory step was not rate-limiting. 4. The composition of bilirubin conjugates in bile was similar in the four groups of rats, despite significant differences in transferase activity. This suggests that the relative proportion of bilirubin mono- and di-conjugates in bile is affected by factors other than transferase activity alone. Relatively more monoconjugates were excreted under the bilirubin load than in basal conditions.


2018 ◽  
Vol 5 (2) ◽  
pp. 5-12
Author(s):  
Jimmy Etukudo Okon ◽  
Gideon Umezuruike Egesie

Background and Objectives: There is increase prevalence of gastric ulcer in the society, but the drugs that are sensitive for radical cure are not screened with physiologic markers such which affect proper management of the disease. The objective of the study is to relate various sources or organ specific templates: gastrin, histamine and prostaglandin relating with the disease in evaluating the potencies of cimetidine, ranitidine and omeprazole for best choice of the drugs in gastric ulcer disease treatment.Material and Methods: Plasma, gastric and antral prostaglandins, histamine and gastrin levels were studied in ninety-six (96), male and female Swiss albino rats for 28 days, using high performance liquid chromatography.Results: Male and female rats with gastric ulcer treated with cimetidine, omepraszole and ranitidine showed no significant difference (P>0.5) in gastrin and the drug groups in plasma, gastric and antral concentrations. But, there was significant difference (P<0.05) in histamine levels between cimetidine, omeprazole and ranitidine in their gastric and plasma concentration. There was no significant difference (P>0.05) in prostaglandin values between cimetidine, omeprazole and ranitidine. Also there was no significant difference (P>0.05) in gastric and plasma levels of gastrin, histamine and prostaglandin between 7, 14, 21 and 28 days treatment period. But, there was significant difference (P<0.05) in antral concentration of gastrin, histamines and prostaglandin between the drug groups. However, there was no significant difference (P>0.05) in antral gastrin between male and female rats in cimetidine and ranitidine treatment. The three drugs were associated with high levels of gastrin, histamine, low prostaglandin though cimetidine showed higher concentration of prostaglandin.Conclusion: It is concluded that gastrin, histamine and prostaglandin are sensitive indicators in evaluating anti-ulcerogenic drugs efficacies.Janaki Medical College Journal of Medical Sciences (2017) Vol. 5(2): 5-12


1998 ◽  
Vol 274 (1) ◽  
pp. R19-R22 ◽  
Author(s):  
Vicky Borovsky ◽  
Mike Herman ◽  
Gail Dunphy ◽  
Ann Caplea ◽  
Daniel Ely

The objective of this study was to determine whether the plasma norepinephrine (NE) increase in rats exposed to CO2asphyxia was due to adrenal gland release or sympathetic nerve ending (SNS) release. Plasma NE was measured by high-performance liquid chromatography in hypertensive and normotensive rats using the following protocol: control session, CO2exposure, N2exposure, reserpine + CO2, and adrenalectomy + CO2. Four strains of male and female rats were used: spontaneously hypertensive rats, Wistar-Kyoto rats, and two congenic strains with different Y chromosomes. The same rats were used throughout the experiment ( n = 80). Blood pressure measured by aortic telemetry increased ∼50–60 mmHg in response to CO2in all strains. CO2increased NE 6–10× in all strains and both genders. N2produced a significant increase in NE (73% of CO2response). Reserpine significantly decreased (67%) plasma NE after CO2. Adrenalectomy did not significantly reduce the NE response to CO2. In conclusion, the increase in plasma NE after CO2was associated with SNS release and not adrenal medullary release, was mainly due to hypoxia, and was not a specific response to CO2.


2020 ◽  
Vol 154 (Supplement_1) ◽  
pp. S85-S86
Author(s):  
J A Martin ◽  
J Figueiredo ◽  
L Wang

Abstract Introduction/Objective Significant technical issues are associated with methods used for the measurement of estradiol.The objective of this study was to qualify an electrochemiluminescent (ECL) assay for the quantification of 17β-estradiol (E2) in rat serum. Hemolysis has been identified as a factor that interferes with accurate measurement.The impact of hemolysis was also assessed. Methods Approximately 1.0 mL of whole blood was collected from male and female rats into separate red top tubes and processed to serum. The LoQ for E2 was evaluated by analyzing the low calibrator or at least 6 serum samples diluted to produce a value at the low end of the reportable range 8 times in the same run.The mean, standard deviation, and %CV were calculated for each sample.The data set was analyzed by plotting the data and determining the concentration at the intersection of the precision profile curve. Linearity of dilution was performed using commercially available calibration verification material and E2 stripped rat serum.The correlation coefficient, the slope, and the % Nominal were calculated. Intra assay precision was evaluated by analyzing 8 consecutive times in a single run one rat serum sample that was not diluted or spiked. This analysis was performed during the evaluation of the LoQ.The mean, SD and %CV were calculated. The interference of hemolysis with the E2 assay was tested by analyzing at least 5 rat serum samples/pools spiked with hemolyzed rat serum at different hemoglobin concentrations.The %RE was calculated. Results The LoQ assays were acceptable. For all samples tested, the % CV was less than or equal to 25%.The LoQ was verified to be 8.50 pg/mL. The %CV was 15.6%. For samples with estradiol concentrations below the LoQ, a value of 4.25 pg/ml was reported. Linearity of dilution for E2 was acceptable.The correlation coefficients were greater than or equal to 0.9000, the slopes were between 0.7500 and 1.2500, and the % nominals for each level were between 75-125%. The intra-assay precision was considered acceptable with a %CV of 8.6%. There was no hemolysis interference in the assay when samples were spiked with hemoglobin concentrations of up to 70 mg/dL, based on the %RE of less than or equal to 25% of non-hemolyzed samples. Conclusion Qualification of the ECL method, demonstrates the assay is suitable for the determination of E2 in serum samples from rats and absence of hemolysis interference up to 70 mg/dL of hemoglobin concentration.


mBio ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Victoria Ozberk ◽  
Simone Reynolds ◽  
Yongbao Huo ◽  
Ainslie Calcutt ◽  
Sharareh Eskandari ◽  
...  

ABSTRACT Infections with Streptococcus pyogenes and their sequelae are responsible for an estimated 18 million cases of serious disease with >700 million new primary cases and 500,000 deaths per year. Despite the burden of disease, there is currently no vaccine available for this organism. Here, we define a combination vaccine P*17/K4S2 comprising of 20-mer B-cell peptide epitopes, p*17 (a mutant derived from the highly conserved C3-repeat region of the M-protein), and K4S2 (derived from the streptococcal anti-neutrophil factor, Spy-CEP). The peptides are chemically conjugated to either diphtheria toxoid (DT) or a nontoxic mutant form of diphtheria toxin, CRM197. We demonstrate that a prime-pull immunization regimen involving two intramuscular inoculations with P*17/K4S2 adjuvanted with a two-component liposomal adjuvant system (CAF01; developed by Statens Serum Institut [SSI], Denmark), followed by an intranasal inoculation of unadjuvanted vaccine (in Tris) induces peptide- and S. pyogenes-binding antibodies and protects from mucosal and skin infection with hypervirulent covR/S mutant organisms. Prior vaccination with DT does not diminish the response to the conjugate peptide vaccines. Detailed Good Laboratory Practice (GLP) toxicological evaluation in male and female rats did not reveal any gross or histopathological adverse effects. IMPORTANCE A vaccine to control S. pyogenes infection is desperately warranted. S. pyogenes colonizes the upper respiratory tract (URT) and skin, from where it can progress to invasive and immune-mediated diseases. Global mortality estimates for S. pyogenes-associated diseases exceeds 500,000 deaths per year. S. pyogenes utilizes antigenic variation as a defense mechanism to circumvent host immune responses and thus a successful vaccine needs to provide strain-transcending and multicompartment (mucosal and skin) immunity. By defining highly conserved and protective epitopes from two critical virulence factors (M-protein and Spy-CEP) and combining them with a potent immunostimulant, CAF®01, we are addressing an unmet clinical need for a mucosally and skin-active subunit vaccine. We demonstrate that prime-pull immunization (2× intramuscular injections followed by intranasal immunization) promotes high sustained antibody levels in the airway mucosa and serum and protects against URT and invasive disease.


1966 ◽  
Vol 101 (3) ◽  
pp. 835-842 ◽  
Author(s):  
B Morgan ◽  
JN Thompson

1. Oxidation of methyl retinoate with monoperphthalic acid gave methyl 5,6-epoxyretinoate, obtained as pale-yellow crystals, m.p. 89 degrees . 2. The structure of the epoxide was confirmed by its ultraviolet, infrared, nuclear-magnetic-resonance and mass spectra. 3. The biological properties of the epoxide were investigated in male and female rats, and were found to be qualitatively similar to those of retinoic acid and methyl retinoate. 4. When administered to male rats reared on a vitamin A-free diet, the epoxide permitted growth although it did not maintain good general health. 5. Rats given a vitamin A-free diet and supplements of the epoxide had degenerate testes. 6. Female rats, maintained on a vitamin A-free diet containing retinoic acid and given supplements of the epoxide during pregnancy, resorbed their foetuses and failed to deliver litters. 7. The threshold of the electroretinogram response in male rats reared on a vitamin A-free diet with supplements of the epoxide was elevated above normal and was similar to that of rats maintained with methyl retinoate. 8. The oral administration of the epoxy acid to rats did not result in the accumulation of the corresponding epoxy alcohol in their livers.


2007 ◽  
Vol 41 (3) ◽  
pp. 372-387 ◽  
Author(s):  
M Lepschy ◽  
C Touma ◽  
R Hruby ◽  
R Palme

Rats are widely used in biomedical research as animal models for human diseases. However, due to their small body size, blood sampling is complicated and invasive and thereby can seriously interfere with endocrine functions and possibly compromise the animals' welfare. Therefore, a non-invasive technique to monitor stress hormones in these animals is highly desired. Our study aimed to gain general information about corticosterone metabolism and excretion and to validate a 5 α-pregnane-3 β,11 β,21-triol-20-one enzyme immunoassay (EIA) to reliably measure faecal corticosterone metabolites (CMs) in laboratory rats. In total, 18 rats were administered 2.3 MBq of 3H-corticosterone intravenously and per os, respectively (intravenous: 6 males and 6 females; per os: 3 males and 3 females). Subsequently, all voided excreta were frequently collected for five days. About 75±9% of the recovered CMs were found in the faeces. Peak concentrations of radiolabelled steroids appeared in the urine after 1.7±0.6 h in males and after 6.0±3.5 h in females. In faeces, maxima were observed after 14.7±2.4 h in both sexes. In principle, the time course and delay for both routes of administration (intravenous or per os) were the same, except for a delay of peak concentrations in urine (4.5±2.1 h) in per os administered males. Using high-performance liquid chromatography (HPLC), faecal 3H-CMs were characterized and differences were found between the sexes. In both sexes, corticosterone was extensively metabolized, but while males showed only minor variations in their CM patterns, those of females differed largely between individuals. To validate the mentioned EIA, we investigated the diurnal variation (DV) of glucocorticoids as well as effects of the injection procedure itself and conducted an adrenocorticotropic hormone challenge test and a dexamethasone suppression test, using six male and six female rats each. Our results demonstrated that pharmacological stimulation, suppression and DV of adrenocortical activity were accurately reflected by means of CM measurement in faeces. By successful physiological validation, we proved for the first time the suitability of an immunoassay to non-invasively monitor adrenocortical activity in rats of both sexes. This method opens up new perspectives for biomedical and pharmacological investigations as well as for animal welfare related issues.


2021 ◽  
Vol 4 (1) ◽  
pp. 99-114
Author(s):  
Janaína B Garcia ◽  
Fernanda G Do Amaral ◽  
Daniela C Buonfiglio ◽  
Rafaela FA Vendrame ◽  
Patrícia L Alves ◽  
...  

The pineal gland synthesizes melatonin exclusively at night, which gives melatonin the characteristic of a temporal synchronizer of the physiological systems. Melatonin is a regulator of insulin activities centrally and also peripherally and its synthesis is reduced in diabetes.  Since monosodium glutamate (MSG) is often used to induce the type 2 diabetic and metabolic syndrome in animal models, the purpose of this work is to evaluate the potential effects of MSG given to neonates on the pineal melatonin synthesis in different aged male and female rats. Wistar rats were subcutaneously injected with MSG (4mg/g/day) or saline solution (0.9%) from the second to eighth post-natal day. The circadian profiles both melatonin levels and AANAT activity were monitored at different ages. Body weight, naso-anal length, adipose tissues weight, GTT, ITT and serum insulin levels were also evaluated. Typical obesity with the neonatal MSG treatment was observed, indicated by a great increase in adipose depots without a concurrent increase in body weight. MSG treatment did not cause hyperglycemia or glucose intolerance, but induced insulin resistance. An increase of melatonin synthesis at ZT 15 with phase advance was observed in in some animals. The AANAT activity was positively parallel to the melatonin circadian profile. It seems that MSG causes hypothalamic obesity which may increase AANAT activity and melatonin production in pineal gland. These effects were not temporally correlated with insulin resistance and hyperinsulinemia indicating the hypothalamic lesions, particularly in arcuate nucleus induced by MSG in early age, as the principal cause of the increase in melatonin production.


1961 ◽  
Vol 38 (1) ◽  
pp. 50-58 ◽  
Author(s):  
N. E. Borglin ◽  
L. Bjersing

ABSTRACT Oestriol (oestra-1,3,5(10)-triene-3,16α,17β-triol) is a weakly oestrogenic substance which, however, in contrast to what was formerly believed, is of physiological significance. Its effect is localized largely to the uterine cervix and vagina. Clinical experience argues both for and against an effect on the pituitary gland. This investigation is concerned with the morphological changes in the pituitary gland and adrenal cortex of gonadectomized male and female rats after the injection of oestriol. It was found that oestriol has the same type of action on these glands as other oestrogens, but under the experimental conditions used, this effect proved much weaker than that produced by oestradiol (oestra-1,3,5(10)-triene-3,17β-diol).


Sign in / Sign up

Export Citation Format

Share Document