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The antioxidant defense system of Varroa destructor mites facilitates the infestation of Apis mellifera

Abstract

Varroa destructor is a parasitic mite of the Western honey bee. The activity of five antioxidant enzymes of V. destructor were analysed. Glutathione content and total antioxidant status was also evaluated. Our results suggest that antioxidant enzymes constitute the main line of defense against ROS in V. destructor, whereas low-molecular-weight antioxidants play a limited role in the antioxidant system of mites.

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Oxidative Stress, Skin Aging and Antioxidant Therapy / Oksidacioni Stres, Starenje Kože I Antioksidaciona Terapija

. The hairless mouse and photoaging. Photochem Photobiol 1991;54:1109-1118. http://dx.doi.org/10.1111/j.1751-1097.1991.tb02134.x 5. Rattan SI. Theories of biological aging: genes, proteins, and free radicals. Free Radic Res 2006; 40:1230-1238. http://dx.doi.org/10.1080/10715760600911303 6. Kohen R. Skin antioxidants: their role in aging and in oxidative stress-new approaches for their evaluation. Biomed Pharmacother 1999;53:181-192. http://dx.doi.org/10.1016/S0753-3322(99)80087-0 7. Stadtman ER. Protein oxidation and

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Antioxidant and free radical scavenging potential of Citrullus colocynthis (L.) Schrad. methanolic fruit extract

References B. Halliwell and J. M. C. Gutteridge, Free Radicals in Biology and Medicine , 3 rd ed., Oxford University Press, Oxford 1999. T. Finkel and N. J. Holbrook, Oxidants, oxidative stress and the biology of aging, Nature 408 (2000) 239-247; DOI:10.1038/35041687. T. P. A. Devasagayam, J. C. Tilak, K. K. Boloor, K. S. Sane, S. S. Ghaskadbi and R. D. Lele, Review: Free radicals and antioxidants in human health: Current status and future prospects, J. Assoc. Phys. India 52

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The Impact of Senile Cataract Maturity on Blood Oxidative Stress Markers and Glutathione-Dependent Antioxidants: Relations with Lens Variables

, Mirić D, Zorić L, Dragojević I, Stolić A. Role of lipid peroxidation in pathogenesis of senile cataract. Vojnosanit Pregl 2009; 66: 371-6. Tarwadi K, Agte V. Linkages of antioxidant, micronutrient, and socioeconomic status with the degree of oxidative stress and lens opacity in Indian cataract patients. Nutrition 2004; 20: 261-7. Micelli-Ferrari T, Vendemiale G, Grattagliano I, Boscia F, Arnese L, Altomare E, et al. Role of lipid peroxidation in pathogenesis of myopic and senile cataract. Br J Ophthalmol 1996; 80

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Evaluation of Systemic Antioxidant Level and Oxidative Stress In Relation to Lifestyle and Disease Progression in Asthmatic Patients/ Evaluacija nivoa antioksidanasa i oksidativnog stresa u sistemu u odnosu na životni stil i progresiju bolesti kod obolelih od astme

oxidative stress in the pathogenesis and treatment of asthma. Curr Opin Allegy Clin Immunol 2008; 8: 49-56. 10. Sackesen C, Ercan H, Dizdar E, Soyer O, Gumus P, Tosun BN, et al. A comprehensive evaluation of the enzymatic and nonenzymatic antioxidant systems in childhood asthma.J Allergy Clin Immu nol 2008; 122: 78-85. 11. Saleh D, Ernst P, Lim S, Barnes PJ, Giaid A. In creased formation of the potent oxidant peroxynitrite in the airways of asthmatic patients is associated with induction of NO synthase: effect of inhaled glucocorticoid

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Antioxidant defences of Norway spruce bark against bark beetles and its associated blue-stain fungus

References 1. Adrian M, Jeandet P, Veneau J, Weston LA, Bessis R. Biological activity of resveratrol, a stilbenic compound from grapevines, against Botrytis cinerea, the causal agent for grey mould. J. Chem. Ecol. 1997;23:1689-1702. 2. Adrian M and Jeandet P. E­ects of resveratrol on the ultrastructure of Botrytis cinerea conidia and biological signi-cance in plant/pathogen interactions. Fitoterapia 2012;83:1345-1350. 3. Alscher RG. Biosynthesis and antioxidant function of glutathione in plants. Physioi

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Wine and Health: A Paradigm for Alcohol and Antioxidants

: 495-504. Catterall F, King LJ, Clifford MN, Ioannides C. Bioavailability of dietary doses of 3H-labelled tea antioxidants (+)-catechin and (-)-epicatechin in rat. Xenobiotica 2003; 33: 743-53. Spencer JP. Metabolism of tea flavonoids in the gastrointestinal tract. J Nutr 2003; 133: 3255S-61S. Meng X, Maliakal P, Lu H, Lee MJ, Yang CS. Urinary and plasma levels of resveratrol and quercetin in humans, mice, and rats after ingestion of pure compounds and grape juice. J Agric Food Chem 2004

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Short Period Storage Impact on Bioactive Constituents from Bilberries and Blueberries

;16:417-428. 4 Dinkova R, Heffels P, Shikov V, Weber F, Schieber A, Mihalev K - Effect of enzyme-assisted extraction on the chilled storage stability of bilberry (Vaccinium myrtillus L.) anthocyanins in skin extracts and freshly pressed juices. Food Res Int. 2014;65:35-41. 5 Syamaladevi RM, Andrews PK, Davies NM, Walters T, Sablani SS - Storage effects on anthocyanins, phenolics and antioxidant activity of thermally processed conventional and organic blueberries. J Sci Food Agric. 2012;92(4):916-924. 6 Manhita AC, Teixeira DM, da Costa CT

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Downregulation in the mRNA expression of nuclear hormone receptor liver-X-receptor alpha (LXR-α) by TNF-α is abolished by the antioxidant kaempferol, but not ascorbic acid, in human hepatocarcinoma HepG2 cells

Abstract

Background: Liver-X-Receptor alpha (LXR-α) plays an essential role in cholesterol metabolism, bile acids, and lipid synthesis. The proinflammatory cytokine TNF-α has been shown to downregulate the expression of LXR-α.

Objectives: We investigated the effects of antioxidants kaempferol and ascorbic acid on LXR-α mRNA expression in TNF-α stimulated HepG2 cells.

Methods: After the cells have reached 60% to 70% confluence, they were treated with 20 ng/ml of TNF-α for 24 hours prior to the stimulation with different concentrations of kaempferol (1 μM, 5 μM, 10 μM, and 20 μM) or ascorbic acid (15 μM, 150 μM, and 1500 μM) for another 24 hours. Total RNA was isolated using TRI Reagent LS (Molecular Research Centre). Reverse transcription quantitative real-time PCR was then conducted to determine the mRNA expression of LXR- α after their respective treatments.

Results: Kaempferol was able to relieve the downregulatory action of TNF-α on LXR-α in a dose-dependent manner. The highest dose of kaempferol (20 μM) almost abolished the action of TNF-α by restoring the levels of LXR-α to its basal levels in HepG2 cells. Twenty μM of kaempferol alone did not produce any significant effect on LXR-α mRNA expression. In contrast, ascorbic acid was unable to counteract the action of TNF-α. In contrast to kaempferol, the highest dose of ascorbic acid (1500 μM) suppressed the expression of LXR-α mRNA in TNF-α stimulated HepG2 cells to 0.571-fold compared with no treatment. In the presence of 1500 μM of ascorbic acid alone, LXR-α mRNA expression was also significantly suppressed to 0.320-fold.

Conclusion: This study demonstrated that kaempferol, but not ascorbic acid, was able to alleviate the TNF-α downregulatory effects on LXR-α mRNA in HepG2 cells. Kaempferol can be a better anti-inflammatory agent than ascorbic acid.

Open access
Physicochemical Traits of Seedless Barberry (Berberis vulgaris L.) Fruits Stored Under Refrigeration as Affected by Heat and Calcium Chloride Treatments

REFERENCES Aghdam, M.S., Dokhanieh, A.Y., Hassanpour, H. & Fard, J.R. (2013). Enhancement of antioxidant capacity of cornelian cherry ( Cornus mas ) fruit by postharvest calcium treatment. Sci.Hortic. ,161: 160-164, https://doi.org/10.1016/j.scienta.2013.07.006 Al-Amier, H. & Craker, L.E. (2007). In-vitro selection for stress tolerant spearmint. Reprinted from: Issues in New Crops and New Uses , J. Janick and A. Whipkey (eds.). ASHS Press, Alexandria, VA, pp. 306-310. Albertini, S., Reyes, A.E.L., Trigo, J.M., Sarriés, G.A. & Spoto, M

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