title: Melatonin: is it an effective antioxidant for pulmonary contusion?
abstract: The goal of the present study was to evaluate the antioxidant effects of melatonin on pulmonary contusion (PC) caused by isolated blunt thoracic trauma (BTT) in an experimental rat model.
  
  
  
  A total of 49 rats were divided into three groups: control group (CG), trauma group (TG), and melatonin group (MG). PC was induced by isolated BTT for all the groups except the control group. Intraperitoneal melatonin was administered to the MG after trauma. Blood and tissue samples were collected from the groups. Malondialdehyde (MDA), total oxidant capacity and total antioxidant capacity (TAOC), arterial blood gas, and other biochemical parameters such as urea, creatinine, alanine aminotransferase (ALT), and aspartate aminotransferase were measured. Lung tissue samples were collected for histopathology.
  
  
  
  On day 2, blood MDA and total oxidant capacity levels were lower, and TAOC levels were higher in the MG compared with the TG (P < 0.001). Blood pH, PO2, and PCO2 of the MG significantly improved on day 2 compared with the TG (P ≤ 0.001). Compared with the TG, histologic damage scores of the MG decreased on day 2 (P = 0.013). Urea, creatinine, ALT, and aspartate aminotransferase levels of the MG on day 2 were lower than TG parameters (P = 0.01, P = 0.02, P = 0.05, and P < 0.001, respectively).
  
  
  
  Our findings demonstrate that melatonin can improve the histopathology of PC and distant organs such as liver and kidney by diminishing oxidative stress. All these findings suggest that melatonin may be an effective new therapeutic agent for PC caused by BTT.
authors: Department of Emergency Medicine, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey. Electronic address: drseri03@hotmail.com.
authors: Serife
authors: S
authors: Ozdinc
authors: Department of Thoracic Surgery, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey.
authors: Gurhan
authors: G
authors: Oz
authors: Department of Pathology, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey.
authors: Cigdem
authors: C
authors: Ozdemir
authors: Department of Biostatistics, School of Veterinary Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey.
authors: Ibrahim
authors: I
authors: Kilic
authors: İzmir Katip Celebi University, Atatürk Training and Research Hospital, Department of Emergency Medicine, Izmir, Turkey.
authors: Zeynep
authors: Z
authors: Karakaya
authors: Department of General Surgery, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey.
authors: Ahmet
authors: A
authors: Bal
authors: Department of Biochemistry, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey.
authors: Tulay
authors: T
authors: Koken
authors: Department of Thoracic Surgery, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey.
authors: Okan
authors: O
authors: Solak
mesh_terms: D055371:Acute Lung Injury / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D001784:Blood Gas Analysis; D003288:Contusions / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D004353:Drug Evaluation, Preclinical; D008168:Lung / Q000473:pathology; D008297:Male; D008550:Melatonin / Q000627:therapeutic use*; D018384:Oxidative Stress; D011897:Random Allocation; D017207:Rats, Sprague-Dawley
chemical_list: D000975:Antioxidants; D008550:Melatonin
keywords: Antioxidant; Blunt thoracic trauma; Experimental study; Melatonin; Pulmonary contusion