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Journal Article 2011; 32(Suppl 2): 37-40 PubMed PMID: 22101881 Citation  Keywords:  Animals, Capsules, Chromatography, Gas, Chromatography, High Pressure Liquid, Dietary Supplements:analysis, Fatty Acids, Omega-3:analysis, Fish Oils:administration & dosage, Fishes, Indicators and Reagents, Malondialdehyde:analysis, Oxidation-Reduction, S.   

OBJECTIVES: To assess the content and composition of fatty acids and tocopherols in commercially available oil capsules, and to assay thiobarbituric acid reactive substances (TBARS) as a marker of oxidation in these oils.

METHODS: Fish and seal oil capsules were analyzed for their contents of long-chain omega-3 fatty acids (DPA, EPA, and DHA), tocopherols, and malondialdehyde.

RESULTS: Large variations were found in the levels of EPA (6.5-40.9%), and DHA (8.1-26.4%), α-tocopherol (117-10282 μg/g), γ-tocopherol (406-2352 μg/g) and δ-tocopherol (127-978 μg/g). The level of malondialdehyde was very low in all capsules.

CONCLUSION: The tested samples of oil capsules showed large variation in quality with respect to long-chain n-3 polyunsaturated fatty acids and tocopherols. The low levels of malondialdehyde indicated a successful oxidation protection strategy....

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Journal Article 2006; 27(Suppl 2): 156-159 PubMed PMID: 17159804 Citation  Keywords:  Animals, Arterial Occlusive Diseases:pathology, Brain Chemistry:drug effects, Carotid Arteries, Gerbillinae, Glutathione:analysis, Ischemic Attack, Transient:pathology, Male, Malondialdehyde:analysis, Melatonin:analogs & derivatives, Protein Carbonylation.   

OBJECTIVES: To investigate whether a new derivative of melatonin, (2,3-dihydromelatonin (DHM), prevented the oxidative stress induced by ischemia /reperfusion (I/R) in the gerbil brain. To specify the effect on endogenous antioxidant activity and protein modification in the brain cortex, we evaluated the contents of glutathione (total GSx=GSH+GSSG) and protein carbonyl groups (PCG).

METHODS: Brain ischemia (I) was induced by (12 min) bilateral carotid occlusion (BCAO) in adult male gerbils (60-70 g b wt.) DHM (10 mg/kg) was administered i.p. 20 min before surgery, at the beginning of reperfusion (R), and then 2 and 6 hours later. Horizontal locomotor activity was recorded using the open-field test over the course of 24 hours. Contents of GSx and PCG were determined after 6h of reperfusion. Glutathione (GSx ) was determined spectrophotometrically using the microplate reader, lactate by the kit Randox, UK. The measurement of protein carbonyl (PCG) groups after their derivatization with 2,4-dinitrophenylhydrazine (DNPH) is the most widely used assessment of protein oxidation. The contents of PCG and malondialdehyde (MDA) were assayed spectrophotometrically.

RESULTS: Evaluation of the data obtained from horizontal locomotor activity recorded over the course of 24 hours using the open-field test showed that hyperactivity induced by I/R was returned by DHM almost to its control value during the interval of up to 6 hours (from 18,000 to 5,000 cm distance traveled, p<0.05). I/R decreased the content of GSx by 27.2% (p<0.001). Administration of DHM resulted in maintaining the content of GSx at control values (p<0.05). DHM diminished the I/R-induced increase in PCG in the cortex by 34.2% (p<0.01).

CONCLUSIONS: Our data indicate that the effect of DHM on the content of glutathione and protein carbonyl groups occurred during the first 6 hours of reperfusion. In this time interval both the content of GSx and protein carbonyl groups seem to be sensitive indicators of I/R-induced oxidative stress in the gerbil brain....

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Journal Article 2002; 23(2): 115-118 PubMed PMID: 12011796 Citation  Keywords:  Adnexal Diseases:complications, Animals, Antioxidants:pharmacology, Female, Guinea Pigs, Lung:chemistry, Malondialdehyde:analysis, Melatonin:pharmacology, Ovariectomy, Pulmonary Edema:drug therapy, Reperfusion Injury:complications, Torsion Abnormality,.   

OBJECTIVES: Pulmonary edema has been shown to occur following ischemia-reperfusion injury in a variety of organs and effects of several pharmacological agents on ischemia-reperfusion-induced damage has been investigated previously. However, there are only a few studies in the literature about pulmonary injury following adnexial ischemia-reperfusion. In this study we aimed at investigating pulmonary changes following adnexial ischemia-reperfusion and the effects of melatonin on noncardiogenic pulmonary edema secondary to adnexial ischemia-reperfusion.

METHODS: A total of 32 Dunkin-Harley guinea pigs were randomly divided into four groups. In group I, oopherectomy was performed following adnexial torsion of three hours (ischemia). Adnexial torsion of three hours followed by a 3 hours detorsion period (reperfusion) and then oopherectomy was performed in remaining three groups. No therapy was given in group one and two while isotonic saline and melatonin was applied intraperitoneally in groups three and four, respectively. Serum malondialdehyde (MDA) levels of operated ovaries and lungs and polimorphonuclear leucocyte infiltration of lungs were determined.

RESULTS: MDA levels in serum, ovary and lungs were higher in detorsion groups (groups II, III) than torsion group (group I) (p<0.01). Melatonin administration significantly decreased the polimorphonuclear leukocytes infiltration of lung parenchime and MDA levels in serum, ovaries and lungs (groups II and IV; groups III and IV; p<0.01, p<0.01). MDA levels and lung tissue PNL infiltration levels of melatonin administered detorsioned group was similar to those levels of only salphingo-oopherectomy performed group (Group I and IV, p>0.05).

CONCLUSION: Pathophysiology of ischemia-reperfusion must be considered in the cases of adnexial torsion where detorsion is thought. As an antioxidant, melatonin administration might be helpful in decreasing post-operative morbidity by decreasing reperfusion injury of lungs....

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