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PubMed1992

Malondialdehyde kit evaluated for determining plasma and lipoprotein fractions that react with thiobarbituric acid.

The determination of thiobarbituric acid reactants (TBARs) is a widely used method for investigating overall lipid peroxidation. An assay kit that could be used with plasma and lipid fractions would facilitate standardization of the method. The results reported here indicate that the malondialdehyde (MDA) kit manufactured by Sobioda (Grenoble, France) complies with criteria of good analytical practices. The detection limit was 0.11 mumol of MDA per liter of plasma. The within-run (CV = 1.8-3.3%) and between-run (CV = 3.3-4.4%) precisions were acceptable. The analytical recovery of MDA after supplementing human plasma samples with tetraethoxypropane standards varied from 88% to 100%. The mean (SD) lipoperoxide concentration determined in 32 healthy adults, ages 20-40 years, was 2.51 (0.25) mumol/L. No significant sex-related difference was noted: 2.57 (0.28) in men vs 2.44 (0.20) mumol/L in women. Applying the method to lipid fractions showed that lipoprotein fractions contain relatively little MDA: 0.07 (0.03) mumol/L of plasma for very-low-density lipoproteins and 0.19 (0.10) mumol/L for low-density lipoproteins.

Adolescent↗

PubMed2004

Serum copper, ceruloplasmin and thiobarbituric acid reactive substance status in patients with ovarian cancer.

Serum copper, ceruloplasmin and thiobarbituric acid reactive substances (TBARS) were estimated in 30 patients of ovarian cancer. The copper to ceruloplasmin ratio was moderately increased (P<0.05) but the copper (P<0.01( and ceruloplasmin (P<0.001) levels were significantly increased in ovarian cancer patients as compared to controls. TBARS levels were also found to be highly significant (P<0.001). Trace elements and free radicals have been implicated in the etiology of cancer. Hence the estimation of antioxidants like ceruloplasmin and TBARS along with the trace element like copper may be of value in the early diagnosis of cancer.

Adult↗

PubMed2005

Diurnal rhythmicity of thiobarbituric acid reactive substances and antioxidants in experimental mammary carcinogenesis.

AIM: Circadian rhythms of reactive oxygen species and antioxidants have been the subject of considerable interest in recent years due to their crucial role in the development of malignant tumors. Our aim was to analyze the circadian pattern of lipid peroxidation by-products (TBARS) and antioxidants status in 7,12-dimethylbenz(a)anthracene (DMBA) induced rat mammary carcinogenesis. METHODS: Mammary tumors were developed in Wistar rats, blood samples were collected at a regular interval of 4 h throughout the 24 h period and TBARS content and antioxidant enzymes activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)) were estimated by colorimetric methods. The Cosinorwin computer software program was used to analyze the characteristics of biochemical rhythms. RESULTS: In mammary carcinogenesis, the acrophase of thiobarbituric acid reactive substances and antioxidant enzymes (SOD, CAT, GPx) in blood were found to be delayed, whilst mesor values for TBARS level - increased, and values for SOD, CAT, GPx activities - decreased. Significant r-values indicate the disruption of lipid peroxidation-antioxidants rhythms in mammary carcinogenesis. CONCLUSION: The present investigation suggests that the circadian pattern of blood lipid peroxidation and antioxidants in rats with mammary carcinoma are markedly desynchronized as compared to normal rats.

Animals↗

PubMed2005

[Concentration of glutathione (GSH), ascorbic acid (vitamin C) and substances reacting with thiobarbituric acid (TBA-rs) in single human brain metastases].

The aim of the study was to estimate the concentration of glutathione (GSH), ascorbic acid (vitamin C) and thiobarbituric acid (TBA-rs) in single human brain metastases and histologically unchanged nerve tissue. The research was conducted on fragments of neoplasmatic tissue collected from 45 patients undergoing surgery in the Department of Neurosurgery, Medical University of Białystok in years 1996-2002. Concentration of GSH was evaluated using the GSH-400 method, vitamin C using the method of Kyaw and TBA-rs using the method of Salaris and Babs. It has been found that there is a decrease of concentration of GSH and vitamin C and a considerable increase (p < 0.05) of concentration of TBA-rs in investigated single brain human metastasis in correlation to the concentration of the mentioned above substances in unchanged nerve tissue.

Adult↗

PubMedDate not supplied

Serum copper, ceruloplasmin, protein thiols and thiobarbituric acid reactive substance status in liver cancer associated with elevated levels of alpha-fetoprotein.

Serum copper, ceruloplasmin, protein thiols and thiobarbituric acid reactive substances (TEARS) were estimated in 25 patients of liver cancer. The copper to ceruloplasmin ratio was moderately increased (P<0.05) but the copper (P<0.001) and ceruloplasmin (P<0.001) levels were significantly increased in liver cancer patients when compared to controls. Protein thiols levels were found to be highly significant (P<0.001). Where as the TEARS levels were not found to be significant. Trace elements and free radicals have been implicated in the etiology of cancer. Hence the estimation of ceruloplasmin and protein thiols along with the copper may be of high value in the early diagnosis of cancer.

Ceruloplasmin↗

PubMed1991

Free and bound malondialdehyde measured as thiobarbituric acid adduct by HPLC in serum and plasma.

Assay of free and total malondialdehyde (MDA) in human serum and plasma from healthy subjects and from patients with high risk of lipoperoxidation was performed as follows: (a) acidic (HClO4, pH 1, at 20 degrees C) or basic (NaOH, pH 13, at 60 degrees C) treatments for 30 min; (b) reaction of the protein-free extract (obtained by acid precipitation) with thiobarbituric acid (TBA); (c) HPLC separation on C18 columns with an eluting solution of methanol/phosphate buffer, 10 mmol/L, pH 5.8 (40/60, by vol), at a flow rate of 1.5 mL/min. Free MDA averaged 0.042 (SEM 0.008) and 0.043 (SEM 0.007) mumol/L, respectively, in serum and plasma from healthy subjects. Free (+/- SEM) MDA increased significantly in the plasma from cancer patients (0.270 +/- 0.047 mumol/L) and from hemodialyzed patients (0.214 +/- 0.035 mumol/L). In serum of hemodialyzed patients, analyses for total MDA were unsuitable because of interfering peaks. MDA bound to NH2 groups constituted 83.2% and 83.5% of total MDA in serum and plasma of healthy subjects, respectively, and only 58% in plasma of hemodialyzed patients.

Adolescent↗

PubMed1990

Thiobarbituric acid test as a measure of lipid peroxidation in Arab patients with NIDDM.

Increased levels of lipid peroxides have been implicated in the pathogenesis of diabetic complications. A convenient and sensitive method for estimation of lipid peroxide concentration is the quantitative estimation of their metabolic end-product malonyldialdehyde (MDA) expressed in mumol/L using the thiobarbituric acid test. The mean fasting MDA value in the plasma of 26 Arab subjects with NIDDM was significantly higher than in healthy controls (14.3 +/- 8.3 vs 2.3 +/- 3.4, p less than 0.001). Within a group of nine diabetic patients with markedly elevated MDA values (greater than 20 mumol/L), eight subjects had retinal changes, four had evidence of coronary artery disease and three had manifest cerebrovascular disease. Macroproteinuria was documented in only three patients in this same group. The mean body mass index was 28.7 +/- 5.4 and the glycaemic control was unsatisfactory with a mean glycosylated hemoglobin of 10.1 +/- 1.5%. The MDA results in an Arabic population were similar to reports in Japanese and British patients and should prove useful as a laboratory test in assessing the severity of the diabetic state, as well as a complementary test in diagnosis and management.

Diabetes Mellitus, Type 2↗

PubMed1990

[Concentration of thiobarbituric acid-reactive substances (TBARS) in the plasma of patients with atherosclerosis with different localizations and different degrees of severity].

The concentration of thiobarbituric acid reactive substances (TBARS) formed as a result of lipid peroxidation and prostanoid metabolism was measured in the plasma of patients with coronary or peripheric atherosclerosis. From the results conclusions were deduced to the function of reactive O2-species in the atherogenesis. We found in plasma of patients with coronary as well as with peripheric atherosclerosis increased TBARS concentrations dependent on the dimension of atherosclerosis as an index of activation of reactive O2-species formation. The TBARS concentration correlated with the cholesterol and LDL-cholesterol concentration in plasma.

Adult↗

PubMed1990

Spectrophotometric correction for bile pigments in the thiobarbituric acid test for malondialdehyde-like substances in plasma.

A simple method is proposed to improve specificity when estimating malondialdehyde-like components of plasma thiobarbituric acid-reactivity, especially with regard to the considerable contribution of bilirubin. The spectrophotometric method comprises measurement of A485, A532 and A560 instead of only A532. A correction formula is then applied to calculate the portion of the A532 which originates from malondialdehyde-like substances. Using this method, normal values for malondialdehyde average 0.84 mumol/l.

Bile Pigments↗

PubMed1990

[The thiobarbituric method for analyzing sugars. III. A method for studying sorbitol dehydrogenase activity].

A method for studying of sorbitol dehydrogenase activity of Acetobacter suboxydans has been worked out which can be applied to other microbe cells too. The enzyme transformation of D-sorbitol into L-sorbose is determined through the reaction between ketohexose and 2-thiobarbituric acid under heating in 1 M oxalic acid (pH = 0.64) medium for 15 or 30 min. The yellow-coloured product was measured at 400 nm. The method is characterized with its high specificity, good reproducibility and accuracy, which allows for its application for quantitative analysis of sorbitol in dietetic foods. For this purpose a sorbitol dehydrogenase preparation isolated from bacterial cells is needed. The main purpose of the spectrophotometric method is to use it as a control in the process of microbial transformation of sorbitol into sorbose both under laboratory and industrial conditions.

Acetobacter↗

PubMedDate not supplied

[Methods of determining lipid peroxidation products in the serum using a thiobarbituric acid test].

Main principles for carrying out of the thiobarbituric acid (TBA)-test of blood serum were characterized. These principles involved incubation of the sample at pH 1.3-1.6, extraction of the reaction products with butanol and spectrofluorimetric or spectrophotometric estimation. Content of TBA-active products in blood serum of healthy donors constituted 3.86 +/- 0.66 nmol malonic dialdehyde per ml of blood serum as shown in fluorimetric estimation by means of the procedure developed.

Humans↗

PubMed1989

[Modification of the determination of lipid peroxidation products in a reaction with thiobarbituric acid].

The aim of the study was to choose the optimal conditions for spectrophotometry of the blood serum lipid peroxidation (LPO) products by the thiobarbituric acid (TBA) test. LPO products have been measured in trichloroacetic acid filtrate and in lipoprotein sediment by spectrophotometry and fluorometry. The optimal conditions for spectrophotometry of TBA-active LPO products are as follows: the proteins are sedimented with 20% solution of phosphotungstic acid, stabilizing the pH values in 1.3-1.5 range; the incubation temperature is 99-100 degrees C; the optic density of the aqueous extract is measured spectrophotometrically at wavelengths 535 and 580 nm. The suggested method permits spectrophotometry of LPO products without additional extraction with butanol, and its results are compatible with those of fluorometry. The coefficient of convergence variations is 3.42%, the repeatability factor 3.31%.

Humans↗

PubMed1988

Specificity of the thiobarbituric acid reaction: its use in studies of lipid peroxidation.

The thiobarbituric acid (TBA) reaction, quantified by colorimetry or fluorimetry, is the method most widely used for studying lipid peroxidation in both laboratory animals and in humans with disorders. However, concerns regarding its analytical specificity have often been expressed, because TBA reacts with a wide variety of chemical species to produce a pink to red color. In this study, we reacted TBA with various saturated and unsaturated aldehydes (both directly and in the presence of sucrose, fructose, and glucose), substituted pyrimidines, 2-deoxyribose, and N-acetylneuraminic acid. We also studied the TBA reaction with bilirubin, biliverdin, icteric serum, and serum containing hemolyzed erythrocytes, comparing the absorption spectra of these reaction products with that for malondialdehyde (MDA). The reaction products were also analyzed for MDA by high-performance liquid chromatography (HPLC). Although the TBA reaction with some of these compounds may not be important in biological studies, others could lead to misinterpretations of increased lipid peroxidation. Use of HPLC to quantify MDA is recommended because of its high analytical sensitivity and specificity, especially in the study of lipid peroxidation in human subjects.

Chromatography, High Pressure Liquid↗

PubMed1988

Hepatic lipid peroxidation in CoCl2-treated rats, evidenced by elevated concentrations of thiobarbituric acid chromogens.

Parenteral administration of cobalt chloride (CoCl2) to male Fischer-344 rats caused hepatic lipid peroxidation, as evidenced by the thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and related chromogens in fresh liver homogenates. After a single sc injection of CoCl2 (300 mumol/kg, body wt.), hepatic concentrations of TBA-chromogens became significantly increased by 4 h and reached peak levels at 24-72 h post-injection. For example, in rats killed 48 h post-injection, hepatic TBA-chromogens (mean +/- SD, N = 7) averaged 607 +/- 141 nmol/g of tissue, wet wt., (P less than 0.01 versus 245 +/- 73 nmol/g in 19 controls). A dose-effect relationship was observed between CoCl2 dosages (100 to 450 mumol/kg, body wt.) and hepatic concentrations of TBA-chromogens in rats killed 24 h post-injection. This study indicates that hepatic lipid peroxidation develops as a consequence of acute CoCl2 toxicity in rats.

Animals↗

PubMedDate not supplied

[Measuring neuraminidase activity by the thiobarbiturate method].

A number of reducing agents used for removing the excess of periodate in the reaction of the neuraminidase (EC 3.2.1.18) activity measuring by the thiobarbituric acid technique were compared. The toxic reagent sodium arsenite may be replaced by a 20% solution of ascorbic acid. The modified technique of the neuraminidase activity determining can be used in case of both high-molecular weight substrate ovomucin and low-molecular weight substrate-glycomacropeptide from milk whey.

Indicators and Reagents↗

PubMed1986

[Thiobarbituric acid positive substances as indicators of lipid peroxidation].

Polyenic acids of particularly membrane-bound lipids can be disintegrated non-enzymatically by oxygen radicals or enzymatically by peroxidation. Final products of the lipid peroxidation are malon dialdehyde, n-alcanes, n-alcanales, hydroxyalcanales, 2-alcenales. Alca-2,4-dienales. Hydroxyalcenales and ketones. Products of lipid peroxidation can react with proteins and glycosaminoglycans. Thus receptor binding of the LDL, enzyme activities, DNA- and protein synthesis can be inhibited. Of the peroxidation products malon dialdehyde is relatively specifically recognizable by the reaction of the thiobarbituric acid. Size and clinical significance of processes of lipid peroxidation are up to now only little known in several diseases, but they might be of great importance for numerous pathological processes.

Chemical Phenomena↗

PubMedDate not supplied

[Level of substances reacting with 2-thiobarbituric acid in the plasma of healthy people and patients with various endocrine diseases].

After estimation of the substances reacting with 2-thiobarbituric acid (malonic dialdehyde, MDA) in human blood plasma using a long-term intralaboratory control of the procedure, increase in content of MDA was observed in blood plasma of patients with endocrinopathies, accompanied by obesity, particularly in the patients with Itsenko--Cushing disease (52 patients before treatment and III patients during various steps of complex treatment). The increase in MDA content in blood of these patients appears to occur due to activation of lipid free radical oxidation.

Adolescent↗

PubMedDate not supplied

[Determination of lipid peroxidation products using thiobarbituric acid in anaerobic states].

Products of lipid peroxidation were estimated in aerobic and anaerobic conditions using thiobarbituric acid (TBA) test. The main amount of malonic dialdehyde estimated in tissue homogenate in presence of oxygen was found to develop during the analytical procedure as a result of lipid peroxidation. At the same time, content of lipid peroxidation primary products did not correlate with amount of malonic dialdehyde in the sample studied. This suggests that TBA analysis may be carried out only under anaerobic conditions.

Anaerobiosis↗