METİLGLİOKSAL VERİLEN RATLARDA KARNOZİNİN ANTİOKSİDAN ÖZELLİKLERİNİN ARAŞTIRILMASI

Öz

Reaktif karbonil bileşiklerinden olan metilglioksal (MGO)’ın, ileri glikasyon son ürünleri (advanced glycation end products; AGE) için bir prekürsör olduğu düşünülmekte ve AGE oluşumu, diyabetes mellitus, ateroskleroz, yaşlanma ve Alzheimer gibi pek çok hastalığın etiyopatogenezinden sorumlu tutulmaktadır. Diğer taraftan endojen dipeptid olan karnozinin, antioksidan ve antiglikasyon özelliklere sahip olduğu ve bu etkileriyle, yukarıda belirtilen hastalıkların önlenmesinde faydalı olabileceği ileri sürülmektedir. Oksidatif ve karbonil stres üzerine MGO’nun muhtemel etkilerini değerlendirmek ve karnozin varlığında, bu etkilerin ne şekilde değişebileceğini araştırmak amacıyla yapılan bu çalışmada; dört gruba ayrılan erkek ratlara 10 gün boyunca intraperitoneal olarak, her gün kg rat ağırlığı başına 1 ml serum fizyolojik (Kontrol grubu), 50 mg MGO (MGO grubu), 200 mg karnozin (Karnozin grubu) ve 50 mg MGO/200 mg karnozin (MGOKarnozin grubu) uygulandı. Ratlardan elde edilen plazma örneklerinde malondialdehit (MDA) ve protein karbonil bileşikleri (PCC) düzeyleri tayin edildi. MGO grubunda bulunan ratların zayıfladıkları ve MGO ile birlikte verilen karnozinin kilo kaybını önemli ölçüde önlediği tespit edildi (p<0.05). MGO grubunda MDA ve PCC seviyelerinin anlamlı şekilde yükseldiği (p<0.05); MGO ile karnozinin kombine olarak verildiği grupta MDA ve PCC seviyelerinin önemli ölçüde azaldığı (p<0.05) belirlendi. Sonuç olarak, patogenezinde AGE oluşumunun rol oynadığı hastalıklarda karnozinin ilave bir terapötik ajan olarak kullanılması önerilebilir

Anahtar Kelimeler

• Metilglioksal, karnozin, oksidatif stres, karbonil stres, rat

Investigation of Antioxidant Properties of Carnosine in Rats Treated with Methlglyoxal

Öz

Methylglyoxal (MGO), one of the reactive carbonyl compounds, is thought to be a precursor for advanced glycation end products (AGE) which are responsible for disorders such as diabetes mellitus and atherosclerosis. On the other hand carnosine, endogen dipeptid, has been suggested to be useful for preventing the disorders mentioned above due to its antioxidant and antiglycation properties. In this study, four groups of male rats were intraperitoneally treated with daily 1 ml serum physiologic (control group), 50 mg MGO (MGO group), 200 mg carnosine (carnosine group) and 50 mg MGO/200 mg carnosine (MGO-carnosine group), per kg of rat weight, for 10 days in order to investigate the effects of MGO on oxidative and carbonyl stress and also whether these effects may be influenced in the presence of carnosine. The levels of malondialdehyde (MDA) and protein carbonyl compounds (PCC) were measured in plasma samples obtained from these groups. Although weight-lose was observed in MGO given rats, it was prevented in the presence of carnosine (p<0.05). Plasma MDA and PCC levels were found to be higher in MGO group (p<0.05); but these values were significantly decreased in the group given MGO together with carnosine (p<0.05). As a result, it may be suggested that carnosine may be used as an additional therapeutic agent in diseases which AGE formation has a role in their pathogenesis

Anahtar Kelimeler

• Carnosine, methylglyoxal, rat, malondialdehyde, protein carbonyl compounds

Kaynakça

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