Specie's differences in glutathione-dependent enzymes in the liver and kidney of two fresh water fishes and their implications for cadmium toxicity

The protective effects of glutathione-dependent enzymes have been studied against cadmium toxicity in the liver and kidney of two fresh water fishesChanna punctatus andClarias batrachus. Specie's differences in the activity of tissue enzymes have also been studied. Cadmium treatment induced lipid peroxidation in the liver and kidney of both species, the kidney being the more susceptible. Enzymological observations revealed thatChanna punctatus is better equipped with conjugating enzymes thanClarias batrachus. Fish having higher activities of these enzymes are thus expected to withstand oxidative stress more effectively.     

Copper and mercury induced oxidative stresses and antioxidant responses of Spirodela polyrhiza (L.) Schleid

Duckweed is recognized as a phytoremediation aquatic plant due to the production of large biomass and a high level of tolerance in stressed conditions. A laboratory experiment was conducted to investigate antioxidant response and mechanism of copper and mercury tolerance of S. polyrhiza (L.) Schleid. To understand the changes in chlorophyll content, MDA, proline, and activities of ROS-scavenging enzymes (SOD, CAT, GPOD) during the accumulation of Cu⁺² and Hg⁺², S. polyrhiza were exposed to various concentrations of Cu⁺² (0.0–40 μM) and Hg⁺² (0.0–0.4 μM). antioxidant activity initially indicated enhancing trend with application of 10 μM Cu⁺²; 0.2 μM Hg⁺² (SOD), of 20 μM Cu⁺²; 0.2 μM Hg⁺² (CAT) and of 10 μM Cu⁺²;0.2 μM Hg⁺² (GPOD) and then decreased consistently up to 40 μM Cu⁺² and 0.4 μM Hg⁺². In the experiment chlorophyll and frond multiplication initially showed increasing tendency and decreased gradually with the application of increased metal concentration. Application of heavy metal has constantly enhanced proline and MDA content while the maximum increase was observed with the application of 40 μM Cu; 0.4 μM Hg for proline and MDA respectively. The upregulation of antioxidant enzymes and proline reveals that S. polyrhiza has strong biochemical strategies to deal with the heavy metal toxicity induced by the accumulation of Cu⁺² and Hg⁺².     

Red-wine Beneficial Long-term Effect on Lipids but not on Antioxidant Characteristics in Plasma in a Study Comparing Three Types of Wine--Description of two O-methylated Derivatives of Gallic Acid in Humans

The purpose of this double clinical study was (1) to evaluate the effect of one single intake (300 ml) of red wine (RW) on the plasma antioxidant capacity (pAOC) and plasma phenolics over the 24-h time period following the intake, and (2) to compare the long-term effects of daily intakes (250 ml/d) of RW, white wine (WW) and Champagne (CH) on the plasma and LDL characteristics of healthy sujects. In the first part, blood samples were collected just before and after wine consumption. In the second part, subjects received the 3 types of wine successively, only at the mealtime, over 3-week periods separated by a 3-week wash out. Blood samples were drawn in fasting condition before and after each 3-week wine consumption period. The peak of pAOC was at 3-4 h following the single intake of RW, that of catechin was at 4 h (0.13 μmol/l) and that of gallic acid and caffeic acid was earlier (≤?1.5 and 0.3 μmol/l, respectively). In plasma, the major form of gallic acid was 4-O-methylated, but a minor form (the 3-O-methyl derivative) appeared. In the long term study, no wine was able to change LDL oxidizability, but some other parameters were modified specifically: RW decreased pAOC (without changing TBARS and uric acid plasma levels), LDL lipids and total cholesterol (TC), and increased plasma apoA1, whereas CH increased plasma vitamin A. The beneficial effect of RW seems to mainly be explained by its action on lipid and lipoprotein constants, and not by its antioxidant one.     

Determination of malondialdehyde in biological fluids by high-performance liquid chromatography using rhodamine B hydrazide as the derivatization reagent

Malondialdehyde (MDA) is a biomarker for lipid peroxidation, and studies of sensitive and selective analytical methods for it are very important for pathological research. The aim of this work was to develop and validate a novel HPLC method for the quantification of MDA in biological fluids using rhodamine B hydrazide (RBH) as the derivatization reagent. After pretreatment and derivatization in acid medium at 50 °C for 40 min, the RBH-derivatized MDA was separated on a Kromasil C₁₈ column at 25 °C and detected by a fluorescence detector at excitation wavelength of 560 nm and emission wavelength of 580 nm. The results showed linearity in the range of 0.8–1500.0 nM with a detection limit of 0.25 nM (S/N = 3). The recovery of MDA from plasma and urine was 91.50 to 99.20%, with a relative standard deviation range of 1.45 to 3.26%. In comparison to other methods reported for the determination of MDA, the proposed method showed superiority in simplicity, more sensitivity, shorter derivatization time, and less interference. The developed method was applied to quantification of MDA in human biological fluids collected from five volunteers with a concentration range of 24.62–245.00 nM.     

Histological changes in placental rat apoptosis via FasL and cytochrome c by the nano-herbal Zanthoxylum acanthopodium

Zanthoxylum acanthopodium has several biological activities, such as antimicrobial, anti-inflammatory, and antioxidant properties. This strong antioxidant herb can be used as a drug for hypertension. FasL and cytochrome c expression play roles in the apoptotic pathway in the placenta. This study focused on the histological change in apoptosis via cytochrome c and Fas ligand expression by investigating whether Zanthoxylum acanthopodium (ZA) fruits affect apoptosis. The present study consisted of five treatments: Normal pregnant rats (C), Hypertension rats (C + ), hypertension rats + extra virgin olive oil (EVOO) (T1), Hypertension rats + ZA (T2), and hypertension rats + EVOO + ZA (T3). Hypertension was induced in rats by injecting 3 mlml of 6% NaCl. Nanoherbal of ZA (100 mg/kg BW) and EVOO (1 ml) were given on the 13th–19th days of pregnancy. Pregnant rats were dissected on the 20th day of pregnancy by cervical dislocation. ELISA assays were performed for the analysis of HSP-70 expression. Immunohistochemistry and TUNEL assays were used to analyse the histological changes in placental tissue. The results showed that cytochrome c and FasL protein exposure levels in the labyrinth, basal, and yolk sac zones were increased during hypertensive pregnancy (P < 0.0001) in rats. The administration of nanoherbal of ZA decreased the expression of cytochrome c and FasL. A significant difference was found in the combination of nanoherbal of ZA and EVOO.     

The modulating effects of tumor necrosis factor alpha antibody on ricin-induced oxidative stress in mice

Previous studies in our laboratory have shown that the protein toxin ricin induces an oxidative stress in mice, resulting in increased urinary excretion of malondialdehyde (MDA), formaldehyde (FA), and acetone (ACON). Other toxicants have been shown to induce oxidative stress by macrophage activation with subsequent release of reactive oxygen species and tumor necrosis factor alpha (TNF-α). Therefore, the ability of TNF-α antibody to modulate ricin-induced urinary carbonyl excretion as well as hepatic lipid peroxidation, glutathione depletion, and DNA single-strand breaks was assessed. Ricin-induced urinary MDA, FA, and ACON were reduced significantly in mice receiving antibody (15,000 U/kg) 2 hours before treatment with ricin (5 μ/kg). At 48 hours following ricin treatment, MDA, FA, and ACON concentrations in the urine of TNF antibody-treated mice decreased 25.7, 53.2, and 64.5%, respectively, relative to ricin-treated mice receiving no antibody. In addition, anti-TNF-α (1500 U/kg) significantly decreased hepatic lipid peroxidation and DNA single-strand breaks, induced by 5 μg ricin/kg, by 49.3 and 44.2%, respectively. The results suggest that macrophage activation and subsequent release of TNF-α are involved in ricin toxicity.     

Use of antioxidants reduce lipid peroxidation and improve quality of crossbred ram sperm during its cryopreservation

Ram sperm are subjected to extreme oxidative stress during their preservation at −196 °C resulting in reduced quality at post thaw. Therefore, the main objective of this study was to evaluate the effect of antioxidants taurine, quercetin and reduced glutathione on the post thaw quality of crossbred ram sperm. A total of twenty four ejaculates from six crossbred rams were collected and extended with tris-based extender with no antioxidant (Control), with taurine (40 mM), quercetin (5 μg/ml) and reduced glutathione (5 mM). The post thaw sperm quality was determined by percent sperm motility, live sperm count, intact acrosome and hypo-osmotic swelling test (HOST) reacted spermatozoa and lipid peroxidation was measured in terms of malondialdehyde (MDA) level both in seminal plasma and sperm cell. At post thaw, percent sperm motility and live sperm count were significantly (p < 0.05) higher for taurine than control and reduced glutathione but did not differ significantly (p > 0.05) from quercetin. The percent HOST reacted spermatozoa were significantly higher for taurine than control, quercetin and reduced glutathione. Seminal plasma MDA level was significantly (p < 0.05) lower for taurine than control and non-significantly lower than quercetin and reduced glutathione. However, spermatic MDA level did not differ significantly (p > 0.05) among the control and antioxidants. In conclusion, taurine at 40 mM reduced lipid peroxidation and improved post thaw sperm quality of cryopreserved crossbred ram semen. Further, transportation time of semen samples in an ice chest at 4–5 °C may be included as a part of equilibration period, when collection shed and frozen semen unit are located at a distance.     

Dietary polyunsaturated fatty acids and heme iron induce oxidative stress biomarkers and a cancer promoting environment in the colon of rats

The end products of polyunsaturated fatty acid (PUFA) peroxidation, such as malondialdehyde (MDA), 4-hydroxynonenal (HNE), and isoprostanes (8-iso-PGF_2α), are widely used as systemic lipid oxidation/oxidative stress biomarkers. However, some of these compounds have also a dietary origin. Thus, replacing dietary saturated fat by PUFAs would improve health but could also increase the formation of such compounds, especially in the case of a pro-oxidant/antioxidant imbalanced diet. Hence, the possible impact of dietary fatty acids and pro-oxidant compounds was studied in rats given diets allowing comparison of the effects of heme iron vs. ferric citrate and of ω-6- vs. ω-3-rich oil on the level of lipid peroxidation/oxidative stress biomarkers. Rats given a heme iron-rich diet without PUFA were used as controls. The results obtained have shown that MDA and the major urinary metabolite of HNE (the mercapturic acid of dihydroxynonane, DHN-MA) were highly dependent on the dietary factors tested, while 8-iso-PGF_2α was modestly but significantly affected. Intestinal inflammation and tissue fatty acid composition were checked in parallel and could only explain the differences we observed to a limited extent. Thus, the differences in biomarkers were attributed to the formation of lipid oxidation compounds in food or during digestion, their intestinal absorption, and their excretion into urine. Moreover, fecal extracts from the rats fed the heme iron or fish oil diets were highly toxic for immortalized mouse colon cells. Such toxicity can eventually lead to promotion of colorectal carcinogenesis, supporting the epidemiological findings between red meat intake and colorectal cancer risk.Therefore, the analysis of these biomarkers of lipid peroxidation/oxidative stress in urine should be used with caution when dietary factors are not well controlled, while control of their possible dietary intake is needed also because of their pro-inflammatory, toxic, and even cocarcinogenic effects.