Formation Of Thiobarbituric Acid Reactive Substances Research Articles

Antioxidant effect of 4-nerolidylcatechol and α-tocopherol in erythrocyte ghost membranes and phospholipid bilayers

4-Nerolidylcatechol (4-NC) is found in Pothomorphe umbellata root extracts and is reported to have a topical protective effect against UVB radiation-induced skin damage, toxicity in melanoma cell lines, and antimalarial activity. We report a comparative study of the antioxidant activity of 4-NC and α-tocopherol against lipid peroxidation initiated by two free radical-generating systems: 2,2′-azobis(2-aminopropane) hydrochloride (AAPH) and FeSO4/H2O2, in red blood cell ghost membranes and in egg phosphatidylcholine (PC) vesicles. Lipid peroxidation was monitored by membrane fluidity changes assessed by electron paramagnetic resonance spectroscopy of a spin-labeled lipid and by the formation of thiobarbituric acid-reactive substances. When lipoperoxidation was initiated by the hydroxyl radical in erythrocyte ghost membranes, both 4-NC and α-tocopherol acted in a very efficient manner. However, lower activities were observed when lipoperoxidation was initiated by the peroxyl radical; and, in this case, the protective effect of α-tocopherol was lower than that of 4-NC. In egg PC vesicles, malondialdehyde formation indicated that 4-NC was effective against lipoperoxidation initiated by both AAPH and FeSO4/H2O2, whereas α-tocopherol was less efficient in protecting against lipoperoxidation by AAPH, and behaved as a pro-oxidant for FeSO4/H2O2. The DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical assay indicated that two free radicals were scavenged per 4-NC molecule, and one free radical was scavenged per α-tocopherol molecule. These data provide new insights into the antioxidant capacity of 4-NC, which may have therapeutic applications for formulations designed to protect the skin from sunlight irradiation.

Antioxidant and anti-inflammatory potential of the aqueous extract and polysaccharide fraction from brown marine macroalgae Padina sp. from Gulf of Mannar of Peninsular India

Objective: To evaluate the antioxidant and anti-inflammatory potential of the aqueous extract and polysaccharide fraction from two brown marine macroalga, Padina gymnospora (P. gymnospora) and Padina tetrastomatica (P. tetrastomatica) harvested from Gulf of Mannar of peninsular India. Methods: The antioxidant activity was evaluated using different in vitro systems, viz., 1,1- diphenyl-2-picrylhydrazyl (DPPH), 2, 2′-azino-bis-3ethylbenzothiozoline-6-sulfonic acid diammonium salt (ABTS), H2O2/ HO. radical scavenging, Fe2+ ion chelating ability, and reducing potential. Folin–Ciocalteu method was used to determine the total phenolic content, and the results were expressed as mg of gallic acid equivalents (GE). Thiobarbituric acid-reactive substance formation inhibition assay was employed to assess the ability of the samples to inhibit lipid oxidation in a model system. COXII and LOXV inhibition assays were employed to assess the anti-inflammatory potential of aqueous extract and polysaccharide fraction. Results: The aqueous extract fraction of P. tetrastomatica realized high total phenolic content (288 mg GE/g), and its activity towards scavenging short-lived radicals (OH. and H2O2) (27.8% and 68.3%, respectively; 0.6 mg/mL) are higher than those registered for Padina gymnospora. Aqueous extract and polysaccharide fractions of P. gymnospora showed higher anti-inflammatory activities against LOXV (56% and 53%, respectively) and COXII (30% and 35%, respectively; 1 mg/mL) enzymes. The correlation studies confirmed that polysaccharides present with the Padina sp. are responsible for their anti-inflammatory potential. IR spectral data of polysaccharide fraction revealed the presence of polysaccharide in alginate for

The antioxidant and cytoprotective activity of Ocimum gratissimum extracts against hydrogen peroxide-induced toxicity in human HepG2 cells

Ocimum gratissimum is used as a traditional folk medicine in many countries. The objective of this study was to evaluate the antioxidant activities of an aqueous O. gratissimum extract (OGE) and to evaluate its cytoprotective activity against hydrogen peroxide-induced toxicity in human HepG2 cells. The results revealed that the total phenolic content of the OGE reached 20%. In the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the OGE reduced up to 80% of the free radicals at a plateau concentration of 66.7 μg/mL. This indicates that OGE contains considerable free radical scavenging activity. In a dose-dependent manner, OGE pretreatment counteracted the decrease in cell viability in H2O2-treated HepG2 cells (p < 0.05), and at a concentration of 20–80 μg/mL, it effectively reduced thiobarbituric acid reactive substance (TBARS) formation. These findings indicated that the aqueous extract of O. gratissimum has an antioxidant capacity and protective effect on oxidative stress in HepG2 cells. This makes OGE a promising therapeutic agent in liver diseases.

Atorvastatin Active Metabolite Inhibits Oxidative Modification of Small Dense Low-Density Lipoprotein

We tested the hypothesis that atorvastatin active metabolite (ATM), on the basis of its distinct structural features and potent antioxidant activity, preferentially inhibits lipid oxidation in human small dense low-density lipoprotein (sdLDL) and other small lipid vesicles. LDL, sdLDL, and various subfractions were isolated from human plasma by sequential ultracentrifugation, treated with ATM, atorvastatin, pravastatin, rosuvastatin, or simvastatin and were subjected to copper-induced oxidation. Lipid oxidation was measured spectrophotometrically as a function of thiobarbituric acid reactive substances formation. Similar analyses were performed in reconstituted lipid vesicles enriched in polyunsaturated fatty acids and prepared at various sizes. ATM was found to inhibit sdLDL oxidation in a dose-dependent manner. The antioxidant effects of ATM in sdLDL were 1.5 and 4.7 times greater (P < 0.001) than those observed in large buoyant LDL and very low-density lipoprotein subfractions, respectively. ATM had similar dose- and size-dependent effects in reconstituted lipid vesicles. None of these effects were reproduced by atorvastatin (parent) or any of the other statins examined in this study. These data suggest that ATM interacts with sdLDL in a specific manner that also confers preferential resistance to oxidative stress. Such interactions may reduce sdLDL atherogenicity and improve clinical outcomes in patients with cardiovascular disease.

Markers of lipid peroxidation and α‐tocopherol levels in the blood and neoplastic tissue of dogs with malignant mammary gland tumors

Excess reactive oxygen species due to oxidative stress and the ensuing lipid peroxidation are believed to be involved in mammary gland tumor (MGT) pathogenesis. The purpose of this study was to evaluate the extent of lipid peroxidation as evidenced by thiobarbituric acid-reactive substances (TBARS) formation, and the concentration of α-tocopherol as an inhibitor of lipid peroxidation, in blood and neoplastic tissue of dogs with malignant MGT. The correlation between inflammatory cell infiltration score and TBARS or α-tocopherol in MGT was also evaluated. Sixteen intact female dogs with malignant MGT and 12 clinically healthy and age/weight-matched controls were included in the study. In all dogs, serum TBARS, α-tocopherol, total cholesterol, and triglycerides were measured. Tissue TBARS and α-tocopherol levels were determined in 1 cm(3) sized tissue samples collected from MGT and adjacent, ipsilateral, normal mammary gland tissue from the 16 affected dogs. The degree of inflammatory cell tumor infiltration was evaluated histologically. There were no statistically significant differences in serum levels of TBARS, α-tocopherol, total cholesterol, and triglycerides between dogs with and without malignant MGT. TBARS were significantly higher, whereas α-tocopherol was lower in neoplastic tissue when compared with normal mammary gland tissue. There was no correlation between TBARS or α-tocopherol concentration and the inflammatory cell infiltration score in neoplastic tissue. The increased level of TBARS suggests oxidative stress induction in canine malignant MGT. The origin of this phenomenon is not clear, as a potential oxidative burst could not be attributed to inflammatory cells infiltrating the tumors.

Coptis chinensis inflorescence and its main alkaloids protect against ultraviolet-B-induced oxidative damage

The protective properties of the Coptis chinensis inflorescence ethanolic extracts (CE) and its main alkaloid components against ultraviolet-B-induced oxidative damage were investigated. The content of berberine, jatrorrhizine, coptisine, epiberberine, and palmatine of CE were determined by HPLC. Results showed that the mixture of five alkaloids contributed to the protective properties of CE in vitro and that berberine had better antioxidant effects than coptisine. Furthermore, the protective properties of CE were investigated in vivo. The skin tissues of UVB-irradiated animals exhibited a significant decrease in glutathione peroxidase, catalase, superoxide dismutase, and hydroxyproline. Additionally, these tissues exhibited a significant increase in the formation of thiobarbituric acid-reactive substances (TBARS). These changes were significantly reversed in a dose-dependent manner after treatment with CE and the standard treatment with gallic acid. Thus, CE and its main alkaloids possess potent protective properties against oxidative damage and may have valuable applications as a kind of tea in the functional food industry.

Antioxidant activity of ginseng cultivated under mountainous forest with different growing years

Ginseng cultivated and grown naturally under mountainous forest is formally called “Lin-Xia-Shan-Shen” (LXSS) and grown in manual condition is called garden ginseng (GG) according to Chinese pharmacopoeia (2010 edition). Usually the growing condition of LXSS is similar to wild ginseng and mostly used in Chinese folks in ancient times. The antioxidant properties of LXSS with different growing years were evaluated by their inhibitions of thiobarbituric acid-reactive substance (TBA-RS) formation in liver homogenate and 2, 2-diphenyl-1-picrylhydrazyl (DPPH)-radical scavenging activity comparing with those of GG. The inhibitions of different polar extracts (n-butanol and water) of LXSS and GG on TBA-RS formation were also evaluated. The results showed that the antioxidant effects of LXSS were higher than those of GG and the TBARS formation inhibition of LXSS with longer growing years were stronger than those with shorter growing years, while the DPPH-radical scavenging activity of LXSS did not show significant difference with the change of the growing year. The results indicated that the inhibitory effect of TBA-RS formation and the DPPH-radical scavenging of LXSS were correlated with the contents of ginsenosides. In adddition, the starch contents of LXSS and GG were determined by micro-amount method with spectrophotometer. It showed that the starch content in GG was higher than that of LXSS whose starch decreased gradually with the growing year.

Cytotoxicity and the induction of the stress protein Hsp 70 in Chang liver cells in response to zearalenone-induced oxidative stress

Zearalenone (ZEN) has been implicated in several cases of mycotoxicosis in farm animals and humans. The toxic effects of ZEN have been well characterized, but little is known regarding the mechanisms of ZEN toxicity, including the involvement of the oxidative stress pathway. Using Chang liver cells as a model, the aim of this study was to determine if ZEN could elevate the expression of the heat shock protein Hsp 70, induce cytotoxicity and modulate the levels of glutathione (GSH) and thiobarbituric acid reactive substance (TBARS). In addition, the cytoprotective effects of N-acetylcysteine amide (NACA) pre-treatment were assessed. Finally, the involvement of oxidative stress in ZEN-induced toxicity was confirmed.The results of this study demonstrated that ZEN-induced Hsp 70 expression in a dose- and time-dependent manners. This effect occurred at low-ZEN concentrations, and could therefore be considered a biomarker of ZEN-induced toxicity. The cytotoxicity was reduced when Chang liver cells were exposed to sub-lethal heat shock prior to ZEN treatment, demonstrating a cytoprotective effect of Hsp 70. This cytoprotective effect suggested that Hsp 70 might play a key role in the cellular defense mechanism. When cells were pre-treated with NACA prior to ZEN treatment, the cells were also protected from toxicity. This NACA cytoprotective effect suggested the involvement of oxidative stress in ZEN-induced toxicity, and this mechanism was supported by reduced Hsp 70 expression, inhibited cytolethality, increased GSH levels and decreased TBARS formation when cells were pre-treated with NACA prior to ZEN exposure.Our data clearly demonstrated that ZEN induced cytotoxicity in Chang liver cells by inhibiting cell proliferation, decreasing GSH levels and increasing TBARS formation in a dose-dependent manner. ZEN also, induced Hsp 70 expression, and the side effects of ZEN were significantly alleviated by pre-treatment with NACA. Oxidative stress is likely to be one of the primary pathways of ZEN toxicity. This oxidative stress may contribute, at least in part, to the mechanism of ZEN-induced cytotoxicity.

The influence of long-term storage, temperature and type of packaging materials on the quality characteristics of frozen farmed Atlantic Salmon (Salmo Salar)

The variations of biochemical, structural, sensory and microbiological characteristics of salmon were examined during the long-term frozen storage at −25 °C, –45 °C and −60 °C. The effects of four different types of packaging materials were studied as well. Lipid oxidation was measured by peroxide value (PV) and thiobarbituric acid reactive substances (TBARS). After 1 year of storage at −25 °C, the concentration of PV in red and white fish muscles increased from 1.26 to 1.82, and from 1.08 to 1.76, respectively. Formation of TBARS was higher in the red muscles than in the white, and reached a value of 14.04 (mg malondialdehyde (MDA) kg−1 of fish) after 1 year of storage at −25 °C. Decreasing the temperature to −45 °C inhibited PV and TBARS formation, but the use of the best packaging materials gave equally good results at −25 °C.The concentrations of oxidation products were quite low for the storage conditions examined, which was reflected by the sensory analyses. The sensory analyses showed that salmon stored for 1 year at −25 °C maintained a level of quality comparable with fresh salmon.The colour alteration was affected by the storage time. The storage at −60 °C reduced drip loss (2.0% from total mass) when compared with those of the higher storage temperatures, but other quality improvements were not significant.

Cardioprotection by the TSPO ligand 4′-chlorodiazepam is associated with inhibition of mitochondrial accumulation of cholesterol at reperfusion

The translocator protein (TSPO) is located on the outer mitochondrial membrane where it is responsible for the uptake of cholesterol into mitochondria of steroidogenic organs. TSPO is also present in the heart where its role remains uncertain. We recently showed that TSPO ligands reduced infarct size and improved mitochondrial functions after ischaemia-reperfusion. This study, thus, sought to determine whether cholesterol could play a role in the cardioprotective effect of TSPO ligands. In a model of 30 min coronary occlusion/15 min reperfusion in Wistar rat, we showed that reperfusion induced lipid peroxidation as demonstrated by the increase in conjugated diene and thiobarbituric acid reactive substance formation and altered mitochondrial function (decrease in oxidative phosphorylation and increase in the sensitivity of mitochondrial permeability transition pore opening) in ex-vivo isolated mitochondria. This was associated with an increase in mitochondrial cholesterol uptake (89.5 ± 12.2 vs. 39.9 ± 3.51 nmol/mg protein in controls, P < 0.01) and a subsequent strong generation of auto-oxidized oxysterols, i.e. 7α- and 7β-hydroxycholesterol, 7-ketocholesterol, cholesterol-5α,6α-epoxide, and 5β,6β-epoxide (+173, +149, +165, +165, and +193%vs. controls, respectively; P < 0.01). Administration of the selective TSPO ligand 4'-chlorodiazepam inhibited oxidative stress, improved mitochondrial function, and abolished both mitochondrial cholesterol accumulation and oxysterol production. This was also observed with the new TSPO ligand TRO40303. These data suggest that 4'-chlorodiazepam inhibits oxidative stress and oxysterol formation by reducing the accumulation of cholesterol in the mitochondrial matrix at reperfusion and prevents mitochondrial injury. This new and original mechanism may contribute to the cardioprotective properties of TSPO ligands.

Phytochemical Profile and Qualification of Biological Activity of an Isolated Fraction of Bellis perennis

This study describes the isolation and identification of apigenin-7-O-ghicopyranoside, a flavonoid isolated from the flowers of Bellis perennis L., Asteraceae, an species with a broad spectrum of biological activities. The in vitro antioxidant activity and the inhibition of the enzyme acetylcholinesterase were evaluated. The flavonoid showed strong in vitro antioxidant potential, because of the capacity of removal of hydroxyl radicals and nitric oxide, and also prevented the formation of thiobarbituric acid-reactive substances. These parameters were inhibited at the highest concentration of ApG at rates of 77.7%, 72% and 73.4%, respectively, in addition to inhibiting acetylcholinesterase, suggesting potential use in the treatment of neurodegenerative diseases.

Assessment of Antioxidant Properties of Tamarind Fruit Pulp and its Effect on Storage Stability of African Bread Fruit Seed dhal and Flour

This study evaluated the antioxidant activities of tamarind fruit pulp in scavenging 1, 1-diphenyl-2-picryl hydroxyl radical (DPPH) and in suppressing thiobarbituric acid reactive substances (TBARS) formation, as a marker of lipid oxidation, in African breadfruit seed dhal and flour. Water and ethanol extracts of tamarind fruit pulp at different concentrations were used to scavenge DPPH radical. Parboiled (100°C; 15 min) breadfruit seeds were dehulled to seed dhal, oven-dried (50°C; 72 h), and half of the dhal milled into flour. Samples (100 g each) of the seed dhal and flour added and mixed together with aqueous suspensions (0, 1.0, 2.0, 3.0 or 5.0 g per 5 ml water) of tamarind fruit pulp were analysed for TBA values within 4 months of storage at 26 ± 2°C. The water and ethanol extracts scavenged DPPH in a dose-dependent manner. The ethanol extract had IC50 of 38.17 while the water extract had IC50 of 7.32, indicating much higher antioxidant activity of water extract. Tamarind fruit pulp inhibited lipid oxidation in breadfruit seed dhal and flour as evident from the mean thiobarbituric acid (TBA) value which decreased with increasing concentrations of the fruit pulp. Antioxidant activity of the fruit pulp was higher in the flour than in the dhal within 4 months of storage. Both seed dhal and flour treated with tamarind fruit pulp had lower mean TBA values ranging from 2.80 to 4.12 ppm Malonaldehyde as against 4.55 to 4.91 ppm for untreated samples. Tamarind fruit can thus be further studied for possible exploitation as a natural antioxidant for use in food, drug and cosmetic products.

Rosmarinic acid ameliorates acute liver damage and fibrogenesis in carbon tetrachloride-intoxicated mice

The aim of this study was to investigate the therapeutic potential of rosmarinic acid (RA), a natural phenolic, in the treatment of acute liver toxicity. RA at 10, 25 and 50mg/kg was administered by gavage once daily for 2 consecutive days, 6h after CCl4 intoxication. CCl4 intoxication caused hepatic necrosis and increased serum ALT activity. In the livers, oxidative/nitrosative stress was evidenced by increased 3-nitrotyrosine (3-NT) and thiobarbituric acid reactive substances (TBARS) formation and a significant decrease in Cu/Zn superoxide dismutase (SOD) activity. CCl4 administration triggered inflammatory response in mice livers by activating nuclear factor-kappaB (NF-κB), which coincided with the induction of tumor necrosis factor-alpha (TNF-α) and cyclooxygenase-2 (COX-2). RA improved histological and serum markers of liver damage and significantly ameliorated oxidative/nitrosative stress and inflammatory response in liver tissue. Additionally, RA prevented transforming growth factor-beta1 (TGF-β1) and alpha-smooth muscle actin (α-SMA) expression, suggesting suppression of profibrotic response. Furthermore, RA significantly inhibited the CCl4-induced apoptosis, which was evident from decreased cleavage of caspase-3. The hepatoprotective activity of RA coincided with enhanced NF-E2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression. The results of this study indicates that RA possesses antioxidant, anti-inflammatory, antiapoptotic and antifibrotic activity against acute liver toxicity.

Oxidative stress induced by arsenopyrite and the role of desferrioxamine-B as radical scavenger

Arsenopyrite (FeAsS) is one of the earth’s primary mineral sources of As, yet its effects on cell damage remain largely unknown. This paper addresses the question whether FeAsS induces lipid peroxidation (LP), a major indicator of oxidative stress. Screening and monitoring of LP was conducted using Thiobarbituric Acid Reactive Substances (TBARSs) assay. The lipid source was supernatant of rat brain homogenates. The formation of TBARS by FeAsS was rapid and took place just after 10min. Maximum TBARS levels (ca. 14nmol TBARS per mg of protein) were observed after 1h and remained constant thereafter. Suspension fraction separations showed that dissolved and structural components contributed to LP. The formation of TBARS by soluble As, As(III) or As(V), compared to basal levels. The initiation of LP by FeAsS was consistent with a mechanism initiated by the Fe3+/O2- redox system, and differed initiated by Fe2+/O2. The effectiveness of FeAsS and FeSO4 as inducer compared, and surpassed that of AAPH. On the other hand, the initiation of LP by FeAsS is consistent with a mechanism initiated by perferryl ion and Fe3+/O2-, and differs from the mechanism characteristic of FeSO4 initiated by the Fe2+/O2 redox system. Proposedly, FeAsS surfaces contain a mixture of Fe3+ and Fe2+ that, along with O2 and O2-, participate in multiple mechanisms of electron transfer. EPR determinations show decreases in DMPO-OH adduct signal in FeAsS suspensions after adding desferrioxamine-B (DFO-B), consistent with the idea that DFO-B serves as a radical scavenger.

Effects of alpha‐lipoic acid in an animal model of mania induced by d‐amphetamine

Oxidative stress and neurotrophic factors are involved in the pathophysiology of bipolar disorder (BD). Alpha-lipoic acid (ALA) is a naturally occurring compound with strong antioxidant properties. The present study investigated ALA effects in an amphetamine-induced model of mania. In the reversal protocol, adult mice were first given d-amphetamine (AMPH) 2 mg/kg, intraperitoneally (i.p.) or saline for 14 days. Between days 8 and 14, the animals received ALA 50 or 100 mg/kg orally, lithium (Li) 47.5 mg/kg i.p., or saline. In the prevention paradigm, mice were pretreated with ALA, Li, or saline prior to AMPH. Locomotor activity was assessed in the open-field task. Superoxide dismutase (SOD) activity, reduced glutathione (GSH), and thiobarbituric acid-reactive substance (TBARS) levels were evaluated in the prefrontal cortex (PFC), hippocampus (HC), and striatum (ST). Brain-derived neurotrophic factor (BDNF) levels were measured in the HC. ALA and Li prevented and reversed the AMPH-induced increase in locomotor activity. PREVENTION MODEL: ALA and Li co-administration with AMPH prevented the decrease in SOD activity induced by AMPH in the HC and ST, respectively; ALA and Li prevented GSH alteration in the HC and TBARS formation in all brain areas studied. REVERSAL MODEL: ALA reversed the decrease in SOD activity in the ST. TBARS formation was reversed by ALA and Li in all brain areas. Furthermore, ALA reversed AMPH-induced decreases in BDNF and GSH in the HC. Our findings showed that ALA, similarly to Li, is effective in reversing and preventing AMPH-induced behavioral and neurochemical alterations, providing a rationale for the design of clinical trials investigating ALA's possible antimanic effect.

Cytoprotective effects of fruit pulp ofEugenia jambolanaon H2O2-induced oxidative stress and apoptosis in rat Leydig cellsin vitro

This study was undertaken to investigate the cytoprotective effect of the fruit pulp of Eugenia jambolana (50-250μgml(-1) ) against the damage induced by H 2 O 2 (100μm) exposure to Leydig cells in vitro. Cell survival with extract was found comparable to similar effects by N-acetyl-l-cysteine. H 2 O 2 -induced rise in thiobarbituric acid reactive substance formation and decline in the activity and expression of antioxidant enzymes like superoxide dismutase, catalase and glutathione-s-transferase were effectively checked. Cellular glutathione and total antioxidant capacity demonstrated significant improvement. The increase in expression of inducible nitric oxide (NO) synthase leading to NO production was successfully countered. Co-treatment of the extract helped in the down-regulation of caspase-3 and poly-ADP-ribose polymerase resulting in a significant reduction in Leydig cell apoptosis induced by H 2 O 2 . Upstream marker proteins of extrinsic (caspase-8, Fas, FasL) and intrinsic (caspase-9) pathway of metazoan apoptosis were identically down-regulated. The Bcl-2 family of proteins, though, remained unaffected. The extract also positively modulated the other marker proteins like c-Jun NH 2 -terminal kinase, p38, Akt, nuclear factor-κB, c-Fos, cellular FLICE-inhibitory protein, cyclooxygenase-2 and p53. Taken together, the above-mentioned findings establish the anti-oxidative and anti-apoptotic potency of the extract that ameliorates the H 2 O 2 -induced adverse effects on rat Leydig cells in vitro.

Hepatoprotective action of dietary bluefin tuna skin proteins on CCl4-intoxicated mice

We have shown that dietary bluefin tuna skin (TUS) protects against carbon tetrachloride (CCl4)-induced hepatic damage in mice. The CCl4-induced necrotic area was decreased in mice fed a TUS-containing diet. Consistent with the decreased necrotic area, dietary TUS markedly lowered the elevated serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities and the thiobarbituric acid-reactive substance (TBARS) formation induced by CCl4 injection. TUS diets also decreased phosphorylation of inhibitory kappa B-α and blocked the translocation of nuclear factor-kappa B to the nucleus. TUS is composed mainly (80.7 %) of type I collagen, and our results revealed that dietary tuna collagen peptides (TUCP) attenuated the increased hepatic necrotic area, serum AST and ALT activities, and liver TBARS levels induced by CCl4, similar to TUS, thus enabling us to attribute the hepatoprotective action of TUS in CCl4-intoxicated mice to tuna collagen. Therefore, TUS and TUCP may be potential food resources that are capable of alleviating hepatitis symptoms.

Pulsed ultrasound associated with gold nanoparticle gel reduces oxidative stress parameters and expression of pro-inflammatory molecules in an animal model of muscle injury

BackgroundNanogold has been investigated in a wide variety of biomedical applications because of the anti-inflammatory properties. The purpose of this study was to evaluate the effects of TPU (Therapeutic Pulsed Ultrasound) with gold nanoparticles (GNP) on oxidative stress parameters and the expression of pro-inflammatory molecules after traumatic muscle injury.Materials and methodsAnimals were divided in nine groups: sham (uninjured muscle); muscle injury without treatment; muscle injury + DMSO; muscle injury + GNP; muscle injury + DMSO + GNP; muscle injury + TPU; muscle injury + TPU + DMSO; muscle injury + TPU + GNP; muscle injury + TPU + DMSO + GNP. The ROS production was determined by concentration of superoxide anion, modulation of antioxidant defenses was determined by the activity of superoxide dismutase, catalase and glutathione peroxidase enzymes, oxidative damage determined by formation of thiobarbituric acid-reactive substance and protein carbonyls. The levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were measured as inflammatory parameters.ResultsCompared to muscle injury without treatment group, the muscle injury + TPU + DMSO + GNP gel group promoted a significant decrease in superoxide anion production and lipid peroxidation levels (p < 0.050). It also showed a significant decrease in TNF-α and IL-1β levels (p < 0.050) when compared to muscle injury without treatment group.ConclusionsOur results suggest that TPU + DMSO + GNP gel presents beneficial effects on the muscular healing process, inducing a reduction in the production of ROS and also the expression of pro-inflammatory molecules.

Damage of testicular cell macromolecules and reproductive capacity of male rats following co-administration of ethambutol, rifampicin, isoniazid and pyrazinamide.

The necessity to minimize adverse effects of tuberculosis chemotherapy requires a comprehensive evaluation of the effects of antituberculosis drugs on the reproductive system and testicular cell macromolecules. The epidemiological situation of tuberculosis in Central and Eastern Europe is getting worse. Data on adverse effects of antituberculosis drugs are scare concerning particularly their effects on the reproductive system. The aim of the present study was to investigate the potential effect of ethambutol, rifampicin, isoniazid and pyrazinamide co-administration on lipid peroxidation, glutathione content and protein SH-groups, DNA fragmentation levels, the reproductive capacity of Wistar male rats and the antenatal development of their posterity. The rats (150–170 g) were divided into two groups: group I – received antituberculosis drugs suspended in 1% starch gel per os: ethambutol – 155 mg/kg b.w./day, rifampicin – 74.4 mg/kg b.w./day, isoniazid – 62 mg/kg b.w./day, pyrazinamide – 217 mg/kg b.w./day, group II (control) – received only starch gel in corresponding volumes. The contents of TBA-active compounds, glutathione and protein SH-groups in testis and sperm were determined spectrophotometrically, the DNA-fragmentation was determined using an UV transilluminator (BIORAD, USA), reproductive system indices were measured by standard methods. The co-administration of therapeutic doses of ethambutol, isoniazid, rifampicin and pyrazinamide to male rats during the period of spermatogenesis caused an increase in the rate of thiobarbituric acid reactive substances formation in testis and sperm, decrease of testis glutathione and protein SH-group contents, significant changes in DNA fragmentation, fatal decrease of male fertilizing capacity and fertility, and increase of pre- and post-implantation embryo lethality. The changes in reproductive indices could be the result of direct or indirect effects of one or more drugs investigated.

Liver tumor promoting effect of omeprazole in rats and its possible mechanism of action

Omeprazole (OPZ), a proton pump inhibitor, is a cytochrome P450 (CYP) 1A1/2 inducer. Some CYP1A inducers are known to have liver tumor promoting effects in rats and the ability to enhance oxidative stress. In this study, we performed a two-stage liver carcinogenesis bioassay in rats to examine the tumor promoting effect of OPZ (Experiment 1) and to clarify a possible mechanism of action (Experiment 2). In Experiment 1, male F344 rats were subjected to a two-third partial hepatectomy, and treated with 0, 138 or 276 mg/kg OPZ by oral gavage once a day for six weeks after an intraperitoneal injection of N-diethylnitrosamine (DEN). Liver weights significantly increased in the DEN+OPZ groups, and the number and area of glutathione S-transferase placental form (GST-P) positive foci significantly increased in the DEN+276 mg/kg OPZ group. In Experiment 2, the same experiment as Experiment 1 was performed, but the dosage of OPZ was 0 or 276 mg/kg. The number and area of GST-P positive foci as well as liver weights significantly increased in the DEN+276 mg/kg OPZ group. The number of proliferative cell nuclear antigen (PCNA)-positive cells also significantly increased in the same group. Real-time RT-PCR showed that the expression of AhR battery genes including Cyp1a1, Cyp1a2, Ugt1a6 and Nqo1, and Nrf2 battery genes including Gpx2, Yc2, Akr7a3, Aldh1a1 Me1 and Ggt1 were significantly upregulated in this group. However, the production of microsomal reactive oxygen species (ROS) and formation of thiobarbituric acid-reactive substances (TBARS) decreased, and 8-hydroxydeoxyguanosine (8-OHdG) content remained unchanged in this group. These results indicate that OPZ, CYP1A inducer, is a liver tumor promoter in rats, but oxidative stress is not involved in the liver tumor promoting effect of OPZ.