Vitamin E as an Antioxidant

Abstract

bsbd@balikesir.edu.tr www.bau-sbdergisi.com ÖZET Li pi t peroksidasyonu bağışıkl ığı, büyümeyi ve üremeyi de i çeren fi zyol oji k fonks i yon l a rın bozulmasına yol açar. Bazı antioksidan enzimler, E ve C vi ta mini gibi eksojen vi taminler i le ba zı mi neraller, hücreleri l ipit peroksidasyonuna karşı korurlar. E vi tamininin moleküler ve hücresel etki leri, antioksidan olarak reaktif oksijen türlerini ve nitrik oksiti temizlemek ya nında s pes i fi k enzi mler ve tra nskripsiyon faktörleriyle de etkil eşerek za rl a r ve l i pi t a l a nl a rı gi bi hücres el ya pıl arı korumaktır. E vi ta mini, hücre zarlarında bul una n uzun zi nci rl i çokl u doyma mış ya ğ a s itlerinin bütünlüğünü korur ve biyoaktivitel eri ni deva m etti ri r. E vi ta mi ni a ynı za ma nda , s teroid hormon üreten dokularda yoğun olarak bulunur ve bu dokul a rda s i tokrom p -450'ni n ol dukça duya rlı s teroidojenik aktivitelerini l ipit peroksidasyonuna karşı korur. Stres, hastalıkl a r ve i mmun ya nıtın teşviki, vi ta mi n ve es a ns i yel el ementl er gi bi bes i n ma ddel eri ne ol a n gereksinimleri arttırabilir. Besinsel dengesizlikler, s ıcak, soğuk, ka l a ba l ık, gürül tü ve ta şınma gi bi s tres unsurları, vücudun s avunma mekanizmalarını zayıfl a ta ra k enfeks i yöz ha s ta l ıkl a ra ya tkınlığa neden olabilirler. Stres durumlarında vi tamin ve minerallere olan gereks i ni m a rta r. Hücre za rına bağlı olan E vi tamini, immun ya nıtları tetikleyen ve düzenleyen kompl eks hücre -hücre etkileşimlerinde önemli bir rol oynar. Ka ra ci ğer ve s erumda ki E vi ta mi ni düzeyl eri , E vi ta mini a lımı veya vücuttaki durumunun güvenilir gös tergel eri di r. Bu derl emeni n a ma cı, E vi ta mininin antioksidan özel l i kl eri i l e i l gi l i bi l gi l eri ve ça l ışma l a rı bi r a ra ya geti rmekti r.Anahtar Kelimeler: Li pi t peroks i da s yonu, a nti oks i da n, E vi ta mi ni , s tres . SUMMARYLi pi d peroxidation l eads to deterioration of phys i ol ogi ca l functi ons i ncl udi ng growth a nd reproduction as well as the i mmunity. Some antioxidant enzymes and the exogenous vi tami ns s uch a s vitamin C a nd E, a nd some minerals protect cells a gainst lipid peroxidation. Mol ecul a r a nd cellular effects of vi tamin E a s a n antioxidant a re to clean the reactive oxygen species a nd ni tri c oxide s ynthase a nd to i nfluence cellular s tructures such as membranes a nd lipid domains by i nteracting with specific enzymes a nd tra nscription factors. Vitamin E maintains integri ty of the l ong chain polyunsaturated fatty a cids that are present in the cell membranes, and retains thei r bioactivity. Vi tamin E i s also i ntensely present i n tissues producing the steroi d hormone, a nd protects the very s ensitive steroi dogeni c a cti vi ti es of cytochrome P-450 a ga i ns t l i pi d peroxi dation i n these tissues. Stress, disease a nd the promotion of the immune respons e ma y i ncrease the need for nutrients s uch as vi tamins a nd essential elements. Stress factors s uch a s nutri tional i mbalances, hot and cold, ...

Effects of The Dietary Supplementation of Layer Diets with Natural and Synthetic Antioxidant Additives on Yolk Lipid Peroxidation and Fatty Acid Composition of Eggs Stored at Different Temperatures and Duration

“…Malondialdehyde levels in eggs stored for 60 days from layers fed thyme remained at the same levels as in fresh eggs (Botsoglou et al, 1997). On the other hand, both natural (D-a-tocopherol) and synthetic forms (DL-a-tocopherol acetate) of vitamin E are frequently used as feed additives, and many studies have shown they have potent antioxidant activity (Traber & Atkinson, 2007;Altiner et al, 2017;Cheng et al, 2017), reducing the levels of thiobarbituric acid reactive substances (TBARS) in eggs during storage (Kaya & Turgut, 2012;Cimrin & Demirel, 2016a;Asadi et al, 2017).…”

Effects of total replacement of dietary fish oil by vegetable oils on growth performance, nutritional quality and fatty acid profiles of rainbow trout (Oncorhynchus mykiss) at optimum and high temperature conditions

“…This case could be originated from the antioxidant property of the vegetable oils. It was proved that vitamin E, one of the strongest natural antioxidants (Altıner et al, 2017), has an immune-enhancing effect compared to a synthetic antioxidant (McDowell et al 1996). Canola, sunflower, corn and peanut oils used in the present study are also rich in vitamin E (İşler, 2018).…”

The Effect of Chitosan and Chitosan Oligosaccharide on Serum Mineral and Vitamin Levels in Rats with Experimental Fluorosis

“…Studies on vitamin levels regarding fluoride exposure are both scarce and conflicting. Apart from its protective effect on lipid peroxidation, vitamin E also has regulatory effects on humoral and cell-mediated immunity (Altıner et al 2017). High α-tocopherol levels in serum have been detected in guinea pigs (Vatassery, et al 1980) and goats (Altug et al 2013) in chronic fluorosis.…”