Protective Effects of Alpha-Lipoic Acid on Oleic Acid-Induced Acute Lung Injury in Rats

Background: Oxidative stress is believed to be an important factor in the pathogenesis of acute lung injury (ALI). Aims: The aim of this study was to investigate the possible protective role of alpha-lipoic acid (aalpha;-LA) on oleic acid (OA)-induced ALI in rats. Study Design: Animal experiment. Methods: A total of thirty-five rats were divided into five groups in the study. Group 1 served as a control group. Rats in Group 2 (aalpha;-LA) were administered aalpha;-LA intraperitoneally at a dose of 100 mg/kg body weight (BW). Rats in Group 3 (OA) were administered OA intravenously at a dose of 100 mg/kg BW. In Group 4 (pre-OA-aalpha;-LA), aalpha;-LA was given 15 minutes prior to OA infusion, and in Group 5 (post-OA-aalpha;-LA), aalpha;-LA was given two hours after OA infusion. Four hours after the OA infusion, rats were decapitated. Blood samples were collected to measure serum levels of malondialdehyde (MDA) and glutathione (GSH), and the levels of activity for superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). Lung tissue samples were taken for histopathological examination. Results: Exposure to OA resulted in increases in serum MDA levels (palt;0.001), as well as histopathological lesions in lung tissue, and decreases in CAT (palt;0.05), GSH-Px (palt;0.05) activities and GSH (palt;0.05) levels. On the other hand, MDA levels were decreased significantly (palt;0.001), while CAT (palt;0.05), GSH-Px (palt;0.01) activities and GSH (palt;0.05) levels were increased significantly in the pre-OA-aalpha;-LA group compared with the OA group. Conclusion: aalpha;-LA was found to lessen oxidative stress and to have positive effects on antioxidants in cases of OA-induced ALI. In conclusion, aalpha;-LA appears to have protective effects against ALI and potential for the prevention of ALI. Turkish Baslik: Ratlarda oleik asit ile olusturulan akut akciger hasarinda alfa-lipoik asidin koruyucu etkileri Anahtar Kelimeler: Akut akciger hasari, oleik asit, aalpha;-lipoik asit, oksidatif stres. Arkaplan: Oksidatif stresin akut akciger hasari (ALI) patogenezinde onemli bir faktor oldugu bilinmektedir. Amac: Bu calismanin amaci, ratlarda oleik asit (OA) ile olusturulan akut akciger hasarinda alfa-lipoik asidin (aalpha;-LA) koruyucu etkilerinin arastirilmasidir. Calisma Tasarimi: Deneysel calisma. Yontemler: Calismada toplam otuz bes rat bes gruba ayrildi. Grup 1 kontrol grubu olarak ele alindi. Grup 2 (aalpha;-LA) ratlara 100 mg/kg dozda aalpha;-LA intraperitoneal (i.p) olarak uygulandi. Grup 3 (OA) ratlara 100 mg/kg dozda oleik asit intravenoz (i.v.) olarak uygulandi. Grup 4'te (pre-OA-aalpha;-LA) OA infuzyonundan 15 dakika once; Grup 5'te (post-OA-aalpha;-LA) ise OA infuzyonundan 2 saat sonra aalpha;-LA verildi. OA infuzyonundan dort saat sonra ratlar dekapite edildi. Serum malondialdehit (MDA) ve glutatyon (GSH) duzeyleri ile superoksit dismutaz (SOD), katalaz (CAT) ve glutatyon peroksidaz (GSH-Px) aktiviteleri olcumu icin kan ornekleri ile histopatolojik inceleme icin akciger doku ornekleri alindi. Bulgular: OA infuzyonunun akciger dokusunda histopatolojik lezyonlarla birlikte, serum MDA duzeylerinde artisa (palt;0.001); CAT (palt;0.05) ve GSH-Px (palt;0.05) aktiviteleri ile GSH (palt;0.05) duzeylerinde ise azalmaya yol actigi belirlenmistir. Buna karsilik, OA grubu ile karsilastirildiginda pre-OA-aalpha;-LA grubunda serum MDA duzeylerinin anlamli sekilde azaldigi (palt;0.001); CAT (palt;0.05) ve GSH-Px (palt;0.01) aktiviteleri ile GSH (palt;0.05) duzeylerinin ise anlamli sekilde arttigi tespit edilmistir. Sonuc: OA ile olusturulan akciger hasarinda aalpha;-LA'nin oksidatif stresi azalttigi ve antioksidanlar uzerinde olumlu etkilere sahip oldugu ortaya konmustur. Sonuc olarak; aalpha;-LA'nin akciger hasarina karsi koruyucu etkisi oldugu ve hasarin onlenmesi acisindan onemli bir potansiyele sahip oldugu dusunulebilir.