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PubMed1998

Fluorometric analysis of 2-thiobarbituric acid reactive substances in turkey.

Three experiments were conducted to develop a sensitive and reliable fluorometric thiobarbituric acid (TBA) reactive substances (TBARS) method to determine lipid oxidation products in meat. The first study was conducted to find the optimum sample preparation conditions for meat in the fluorometric method. The second study was to compare the original and the modified methods by using meat and blood samples. The modified fluorometric method was compared with a conventional spectrophotometric method in a third study. Four different extraction solutions (2.5 M acetic acid, 0.5 M hydrochloric acid, 0.8 M perchloric acid, and 1.4 M trichloroacetic acid) and two ratios of extraction solution to TBA (20 mM) solutions (2:1 and 1:1) were examined in the first study. Hydrochloric acid was the optimum among the four extraction solutions tested, and the ratio of extraction solution to TBA solution at 1:1 was the best for the fluorometric TBARS method in raw ground turkey. The modified fluorometric method had high recovery rates (91%, average), and the regression coefficient of the standard curve prepared with spikes was also high (r2 = 0.99). The analysis of raw meat and plasma samples indicated that the modified fluorometric method had greater sensitivity than the original method. The pH of the reaction mixture played an important role in extraction TBARS from samples, and low pH conditions were preferable to high pH conditions. The amount of lipid oxidation products in raw turkey breast meat indicated that the fluorometric method had much greater sensitivity than the spectrophotometric method. The results from the three studies showed that the modified fluorometric TBARS method was useful for the samples with low lipid oxidation products, such as fresh raw meat. The sensitivity of the modified fluorometric method also facilitates the determination of oxidation products in small quantities of samples.

Animals↗

PubMed1989

The contractile responses of isolated dog cerebral and extracerebral arteries to oxybarbiturates and thiobarbiturates.

In helical strips of dog cerebral, coronary, mesenteric, renal, and femoral arteries, the addition of thiamylal and thiopental, 10(-5) to 10(-3) M, caused a dose-related contraction; the contraction was significantly more intense in cerebral than in extracerebral arteries. Secobarbital caused a slight contraction only in the cerebral artery. In contrast, pentobarbital did not produce a contraction in any artery studied. The thiamylal-induced contraction was not affected by treatment with phentolamine, diphenhydramine, or cinanserin but was attenuated by treatment with Ca entry blockers, such as nifedipine or diltiazem. In the cerebral artery soaked in Ca++-free media for 60 min, the addition of Ca++ produced triphasic responses; a transient contraction followed by a relaxation and a slowly developing, persistent contraction. The persistent contraction was potentiated by 10(-4) M thiamylal but abolished at 10(-3) M. In the mesenteric artery soaked in Ca++-free media, the addition of Ca++ produced only a slight contraction, which was potentiated by thiamylal (10(-4) and 10(-3) M). It is concluded that thiobarbiturates are more potent vasoconstrictors than oxybarbiturates and that the barbiturates produce greater contraction in cerebral arteries than in extracerebral arteries. The thiamylal-induced contraction appears to be associated mainly with influx of Ca++ from extracellular fluids.

Animals↗

PubMed1983

Amino acids and thiobarbituric acid reactive substances in cerebrospinal fluid and plasma of patients with septic encephalopathy.

Amino acids and thiobarbituric acid reactive substances (TBARs) in the cerebrospinal fluid (CSF) and plasma were identified and assayed in 5 patients with septic encephalopathy. Levels of all the high molecular weight neutral amino acids (LNAAs) appeared to increase in the CSF. CSF levels of phenylalanine (PHE) and methionine (MET) increased significantly by factors of 20.9 and 9.5, respectively, and the plasma PHE level increased 7.5-fold. No significant changes in branched-chain amino acids were observed in either the CSF or plasma. The CSF/plasma ratios of valine (VAL), tyrosine (TYR), PHE, and MET significantly increased to 0.21, 0.46, 0.52, and 0.52, respectively. TBAR levels increased 4-fold in the CSF and also were slightly increased in the plasma, suggesting that lipid peroxidation in the central nervous tissues is markedly increased. We conclude that increases in LNAA levels and in lipid peroxidation in the central nervous tissues may play important roles in the development of septic encephalopathy.

Aged↗

PubMed1994

Different roles of 8-hydroxyguanine formation and 2-thiobarbituric acid-reacting substance generation in the early phase of liver carcinogenesis induced by a choline-deficient, L-amino acid-defined diet in rats.

The present study was performed to assess the roles of hepatocellular oxidative damage to DNA and constituents other than DNA in rat liver carcinogenesis caused by a choline-deficient, L-amino acid-defined (CDAA) diet by examining the effects of the antioxidant N,N'-diphenyl-p-phenylenediamine (DPPD). The parameters used for cellular oxidative damage were the level of 8-hydroxy-guanine (8-OHGua) for DNA and that of 2-thiobarbituric acid-reacting substance (TBARS) for constituents other than DNA. A total of 40 male Fischer 344 rats, 6 weeks old, were fed the CDAA diet for 12 weeks with or without DPPD (0.05, 0.10 or 0.20%) or butylated hydroxytoluene (BHT, 0.25%). In the livers of the rats, the numbers and sizes of glutathione S-transferase (EC 2.5.1.18) placental form (GSTP)- and/or gamma-glutamyltransferase (GGT, EC 2.3.2.2)-positive lesions and levels of 8-OHGua and TBARS were determined. The GSTP-positive lesions of 0.08 mm2 or larger were all stained positively for GGT as well in cross-sectional area, whereas the smaller lesions were generally negative for GGT. DPPD and BHT reduced the size of the GSTP-positive lesions without affecting their total numbers. At the same time, they reduced TBARS generation without affecting 8-OHGua formation in DNA. The present results indicate that oxidative DNA damage (represented by 8-OHGua formation) and damage to constituents other than DNA (represented by TBARS generation) may play different roles in rat liver carcinogenesis caused by the CDAA diet; the former appears to be involved in the induction of phenotypically altered hepatocyte populations while the latter may be related to the growth of such populations.

Animals↗

PubMed1989

Suppression of neutrophil migration and chemiluminescence is due to the sulphur atom in the thiobarbiturate molecule.

In this study the hypothesis was tested that the substituent at the C 2 position of the barbiturate molecule is crucial for the obvious differences in inhibitory potencies between various barbiturates with respect to neutrophil functions in vitro. Using isolated neutrophils from healthy volunteers, the comparative effects of two pairs of sulphur or oxygen-substituted analogues on chemiluminescence, random and chemotactic migration were examined. Five other i.v. barbiturates were also tested in the chemiluminescence assay. The key observation with all the assay systems was that the oxybarbiturates proved ten to a hundredfold less suppressive than their sulphurated analogues or the other thiobarbiturates. Thus, enhanced inhibitory potency was dependent on the presence of the sulphur atom in the barbiturate molecule and could no longer be explained exclusively on the basis of divergent physicochemical features.

Chemotaxis, Leukocyte↗

PubMed2006

Broad-band ultraviolet B phototherapy is associated with elevated serum thiobarbituric acid reactive substance and nitrite-nitrate levels in psoriatic patients.

BACKGROUND: Although the local anti-inflammatory, immunosuppressive and oxidative activity of UVB is known, the systemic effect of UVB phototherapy in dermatological patients has not been investigated. OBJECTIVE: We aimed to investigate the lipid peroxidation status (as represented by thiobarbituric acid reactive substance, TBARS) and nitrite-nitrate levels in psoriatic patients under broad-band ultraviolet B (BB-UVB) phototherapy in order to determine the systemic effects of UVB. SUBJECTS AND METHODS: Thirty-two psoriatic patients and 20 healthy controls were included. Blood samples were obtained at the beginning, after 6-10 exposures to BB UVB phototherapy (mean 5 weeks) and at the end of the therapy period (mean 21 weeks). Serum TBARS and nitrite-nitrate levels were evaluated. RESULTS: There was no statistically significant difference in serum TBARS and nitrite-nitrate levels between psoriatic patients (basal) and healthy volunteers. There was no statistically significant correlation between disease duration, disease severity, or the total cumulative dose of UVB and serum levels of TBARS and nitrite-nitrate in psoriatic patients. Total nitrite levels in samples obtained during and at the end of therapy were significantly higher than basal levels (P=0.033 and P=0.005, respectively). TBARS levels in samples obtained during and at the end of therapy were significantly higher than basal levels (P=0 and P=0.026, respectively). There was a negative correlation (r=-0.576, P=0.039) between the total nitrite and TBARS levels in psoriatic patients at the end of therapy. CONCLUSION: Our study showed that chronic exposure to UV irradiation may lead to a systemic effect on lipid peroxidation and NO levels, which are shown by a significant elevation in TBARS and nitrite-nitrate levels in serum.

Adult↗

PubMed1980

Lipid peroxidation in rat brain cortical slices as measured by the thiobarbituric acid test.

Malonaldehyde formation by cortical brain slices from rat brain was determined as a function of incubation time and of oxygen pressure. This substance, a byproduce of lipid peroxidation, was detected by the thiobarbituric acid test. Significant amounts of malonaldehyde were formed by brain slices during incubation in the 0.2 (air) to 10 atm oxygen range, and a portion of it was released into the medium. The rate of malonaldehyde formation was the highest during the first 10 min. Elevation of oxygen pressure above 1 atm caused further increments in malonaldehyde production with kinetic properties similar to that seen at 1 atm pressure, but the increments per additional oxygen pressure were diminishing. The formation of a given amount of malonaldehyde can be expressed as a function of atm oxygen X min. This function has the shape of a saturation curve approaching a maximum at around 300 atm X min. The results indicate extensive lipid peroxidation in brain slices under standard incubation conditions.

Aerobiosis↗

PubMed1984

Production of thiobarbituric acid-reactive material during experimental cardiopulmonary bypass in cows.

Increased levels of thiobarbituric acid (TBA)-reactive material were found in the plasma of cows during experimental cardiopulmonary bypass. The levels of TBA-reactive substance decreased during the postoperative period to levels statistically lower (50%; p less than 0.001) than the preoperative values. The increased TBA reactivity of the plasma is indicative of lipid peroxidation during the perfusion period, owing either to exposure of the blood to increased PO2 or to oxygen radical formation. Activation of phagocytic cells by membrane contact and complement activation can induce phagocytic killing processes with the release of oxygen radicals. Although the absolute neutrophil count increased during the perfusion period, convincing correlation with the TBA reactivity was not found, and the origin of the TBA-reactive material remains speculative.

Animals↗

PubMed2006

Thiobarbituric acid reactive substances, Fe3+ reduction and enzymatic activities in cultures of Ganoderma australe growing on Drimys winteri wood.

Ganoderma australe is a basidiomycete responsible for a natural process of selective and extensive lignin degradation. Fatty acids, thiobarbituric acid reactive substances (TBARS), Fe3+-reduction and enzymatic activities were monitored in cultures of G. australe growing on Drimys winteri wood chips. Linoleic acid was de novo synthesized, and steadily increased during 12 weeks of cultivation. Part of the unsaturated fatty acids underwent peroxidation as TBARS accumulated with biodegradation time. TBARS accumulation was proportional to the wood weight and component losses. Manganese-dependent peroxidase and lignin peroxidase were not detected in the culture extracts, whereas laccase-induced oxidation of syringaldazine peaked after 2 weeks (104+/-9 micromol oxidized min(-1) kg(-1) of dry wood), subsequently decreasing. On the other hand, nonenzymatic Fe3+-reducing activity increased as a function of cultivation time and could be involved in the initiation of lipid peroxidation.

Biodegradation, Environmental↗

PubMed1991

Plasma thiobarbituric acid reactive substances a predictive marker of cerebral ischemia in patients at high risk?

The clinical meaning of high values of blood lipid peroxides, assessed as thiobarbituric acid reactive substances (TBA-RS), was investigated in 19 selected high risk patients with transient ischemic attacks (TIA). Patients were checked every 3-6 months and followed-up for 3 years. 8 patients experienced further vascular episodes, 4 having minor stroke and 4 TIA; one of the latter died from myocardial infarction. Unlike blood cholesterol and glucose. TBA-RS values discriminated patients with vascular episodes: they, indeed, showed significant higher values of TBA-RS. Discriminant analysis further indicated that TBA-RS levels differentiate patients with and without vascular accidents, suggesting that high blood values of lipid peroxides could represent a predictive sign of vascular ischemia.

Aged↗

PubMed1991

Release of 2-thiobarbituric acid reactive products from glutamate, deoxyuridine or DNA during autoxidation of dopamine in the presence of copper ions.

Cytotoxic effects of catecholamine are thought to be caused by the formation of 0-semiquinone and superoxide radicals. Dopamine in the presence of copper ions releases aldehydic products from glutamate, deoxyuridine or DNA capable of reacting with 2-thiobarbituric acid (TBA). The formation of TBA reactive products (TBAR) was concentration dependent of both dopamine and copper ion. Complete inhibition of formation of TBAR from glutamate, deoxyuridine or DNA was observed in the presence of thiourea and catalase. Mannitol, albumin and superoxide dismutase offered substantial protection. The present data indicate that dopamine in the presence of copper ions can lead to the formation of reactive hydroxyl radicals which can release aldehydic products from glutamate, deoxyuridine or DNA capable of reacting with TBA.

Aldehydes↗

PubMed1994

Photosensitization with a chlorin-thiobarbiturate conjugate.

The photobiologic properties of a chlorin-thiobarbiturate conjugate were examined. In addition to the characteristic 670 nm chlorin absorbance, the conjugate exhibited new absorbance bands at 517 and 743 nm, but these were not a part of the fluorescence emission spectra, nor was fluorescence observed at wavelengths > 670 nm. The action spectrum indicated that the long-wavelength absorbance of the conjugate was not involved in phototoxicity in cell culture, and that only irradiation at wavelengths associated with the chlorin moiety yielded a cytotoxic effect. In vivo cytotoxicity elicited by 745 nm irradiation is attributed to thermal effects.

Animals↗

PubMed1998

Simultaneous production of carbon monoxide and thiobarbituric acid reactive substances in rat tissue preparations by an iron-ascorbate system.

Most of the carbon monoxide (CO) produced by mammals is a product of the heme oxygenase (HO) reaction, the rate-limiting step in the heme degradation pathway leading to the generation of bilirubin in man. However, some CO is derived from other sources. We studied the association of CO production with lipid peroxidation in tissue preparations from adult male Wistar rats. Supernatants, from 20% tissue homogenates in potassium phosphate buffer, centrifuged for 1 min at 13,000 x g, were incubated for 30 min at 37 degrees C in septum-sealed vials in the dark with ascorbate (100 microM) and Fe(II) (6 microM) and (or) Fe(III) (60 microM). Butylated hydroxytoluene (BHT, 100 microM) was added for the blank reaction. CO produced into the headspace was quantitated by gas chromatography. Thiobarbituric acid reactive substances (TBARS), conjugated dienes (CD), and lipid hydroperoxides (LOOH) in the reaction medium were quantitated by spectrophotometry. Of the tissues studied, CO and TBARS formation was greatest for brain, followed by kidney, lung, spleen, and blood, but no CO or TBARS formation was detected for testes, intestine, liver, and heart. Cell fractionation studies indicated that these differences might be due to the presence of endogenous soluble antioxidants in the latter tissues. Furthermore, these studies demonstrated that CO was exclusively generated by subcellular fractions that contained membranes. The magnitude of the rate of product formation in brain supernatants depended on the concentration of Fe(II) and (or) Fe(III). The formation of CO, TBARS, CD, and LOOH increased linearly with time for up to 30 min, but the rates of product formation were different. Product formation was completely inhibited by BHT (100 microM), biliverdin (50 microM), bilirubin (50 microM), citrate (100 microM), and the Fe(II) chelators, desferrioxamine mesylate (100 microM) and diethylenetriaminepentaacetate, but not by 10 microM of the HO inhibitor, zinc deuteroporphyrin bis glycol. We conclude that CO generation is associated with the process of in vitro lipid peroxidation in tissues with limited antioxidant reserves.

Animals↗

PubMed2005

Daytime of sampling, tooth-brushing and ascorbic acid influence salivary thiobarbituric acid reacting substances--a potential clinical marker of gingival status.

BACKGROUND: Salivary thiobarbituric acid reacting substances (TBARS) have been previously shown to correlate with the impairment of gingival tissue. Although the details on the origin and the composition of this heterogeneous group of compounds in saliva are unknown, the potential clinical usefulness makes necessary the studies of factors influencing the salivary TBARS levels. AIM: To observe the effects of daily dynamics, tooth-brushing and ascorbic acid administration on salivary TBARS levels. Subjects and methods. Self-collected samples were obtained from 10 young healthy men collecting samples in the morning, in the afternoon and in the evening during 2 consecutive days. Ascorbic acid (250 mg) was administered orally after the last sampling on day 1 and before every sampling on day 2. Additional sampling was performed before and after tooth-brushing. TBARS levels in saliva specimens were detected spectrofluorometrically. Sialic acid content was measured using a modified method of Warren. RESULTS: Salivary TBARS levels vary significantly during a day (p < 0.001) with highest concentrations in the morning. Both, tooth-brushing (p < 0.05) and short-term antioxidative treatment with ascorbic acid (p < 0.005) decrease salivary TBARS levels. Sialic acid content of saliva is not influenced significantly by any of the investigated factors. CONCLUSION: TBARS levels in saliva are affected by daytime of sampling, tooth-brushing and ascorbic acid pre-treatment. These results must be considered in clinical research using salivary TBARS levels. Sialic acid seems not to be a major component of TBARS in saliva. Further studies should clarify the molecular compounds of salivary TBARS and uncover the role of oral microbial factors.

Adult↗

PubMed2005

Salivary thiobarbituric acid reacting substances and malondialdehyde--their relationship to reported smoking and to parodontal status described by the papillary bleeding index.

BACKGROUND: Thiobarbituric reacting substances (TBARS) are markers of lipoperoxidation. The best-known specific TBARS is malondialdehyde (MDA). Results from our previous studies have shown that TBARS can be measured in saliva and are increased in patients with gingivitis. Whether MDA is the main TBARS in saliva from patients with altered parodontal status is unknown. Aim. To observe the relationship between the parodontal status and TBARS, MDA and the number of epithelial cells in saliva. SUBJECTS & METHODS: In Study I saliva and plasma samples of 15 patients (8F, 7M) suffering from inflammatory periodontal diseases were gathered and TBARS levels were measured in these samples. In Study II saliva samples from 217 consecutive stomatologic patients were collected and analysed for TBARS spectrofluorometrically, MDA by high-performance liquid chromatography and epithelial cell count by light microscopy. Papillary bleeding index (PBI) was determined in standard stomatologic examination. RESULTS: In Study I results from our previous studies showing no correlation between salivary and plasma TBARS levels were confirmed. This indicates that the local salivary level of TBARS is unlikely to be directly affected by systemic oxidative stress. In Study II higher PBI was associated independently (adjusted for age and sex) tightly with higher TBARS (p<0.001) and with lower number of epithelial cells in saliva (p<0.05). Smokers had higher salivary MDA levels (p<0.003) and lower number of epithelial cells in saliva (p<0.01). CONCLUSION: Salivary TBARS are a simple parameter that partially reflects the parodontal status with a potential usefulness in the clinical stomatology. We show herein that salivary MDA is dependent on age and smoking, but there is no correlation between MDA and PBI. Further studies should uncover the main salivary TBARS compound in patients with altered parodontal status and trace the origin of these salivary lipoperoxidation markers.

Adult↗

PubMed2006

Testicular nitric oxide and thiobarbituric acid reactive substances levels in obstructive azoospermia: a possible role in pathophysiology of infertility.

OBJECTIVE: The aim of the study is to evaluate the levels of nitrite/nitrate and thiobarbituric acid reactive substances (TBARS) and their relationship with seminal parameters in experimental obstructive azoospermic rats to explain the possible mechanism of impaired sperm quality in obstructive azoospermia. METHODS: A total of 10 male Spraque-Dawley rats underwent bilateral vas resection and ligation (Group-1 = vasectomy group). The findings were compared with control group (Group-2 = sham group, n = 10). Animals were sacrificed 8 weeks after surgery. Testes were removed and used for the evaluation of nitrate/nitrite and TBARS levels and for histology. Epididymal-aspirated seminal plasma was used for semen count and morphological analysis according to the Kruger criteria. RESULTS: Testicular tissue nitrate/nitrite and TBARS levels were 35.7 +/- 3.1 micromol/g protein and 3.7 +/- 0.1 nmol/g protein in Group-1, and 19.3 +/- 0.7 micromol/g protein and 3.1 +/- 0.1 nmol/g protein in Group-2, respectively. Both parameters showed statistical differences between the two groups. Testicular tissue nitrate/nitrite and TBARS levels showed negative and statistically significant correlations with sperm motility and morphology. CONCLUSIONS: The present study showed that testicular nitrate/nitrite and TBARS levels were increased in obstructive azoospermia. For that reason, we concluded that antioxidant treatment can be recommended to patients before sperm extraction for artificial reproduction due to obstructive infertility after vasectomy reversal.

Animals↗

PubMedDate not supplied

Effects of aging and dementia on the levels of thiobarbituric-acid-reactive products stimulated by L-glutamic acid in human autopsy and biopsy brain tissue.

Basal and stimulated (by L-glutamic acid, GA) levels of thiobarbituric-acid-reactive products were estimated in the brain tissue (hippocampus, cortex and cerebellum) from autopsy samples of people with Alzheimer disease (AD), multi-infarct dementia (MID) and from nondemented control patients. The experiment was also performed on biopsy brain tissue (cortex) of nondemented controls. The biopsy brain tissue influenced by normal aging in vivo showed a limited susceptibility to undergo lipid peroxidation stimulated by GA in vitro in comparison with the younger tissue. A significant decrease in the ratio of stimulated to basal levels was found in the cerebellum of MID patients in comparison with nondemented controls and AD patients.

Aged↗

PubMed1981

Thiobarbituric acid reactive material in uremic blood.

The thiobarbituric acid (TBA) assay was applied to uremic blood. Significant TBA-reactive material was found in patients with chronic renal failure compared to normal controls. The presence of TBA-reactive material correlated with the degree of renal failure, and was removed by hemodialysis. The reactive material is not 2-deoxyribose or sialic acid. In addition, the presence of TBA-reactive material in uremic blood is not abolished by prior aspirin ingestion, suggesting it is not related to active prostaglandin synthesis. The possible origin of the TBA-reactive material in uremic blood is discussed.

Adult↗