B.Cayci 1, B.Günaydın 1,S.Yuksel 1, S.Soylemez 1, C.Altundarak 2 Gazi University School of Medicine 1 & Hacettepe University Faculty of Sports Science 2 Ankara, Turkey www.berringunaydin.com
Outline Oxidative stress and smoking Malondialdehyde(MDA) in smokers and non-smokers MDA Analysis Effect of smoking
Background OXIDATIVE STRESS is an imbalance between oxidants and antioxidants on a cellular base One of the particular sources of oxidative stress is smoking One of the particular biomarkers of oxidative damage is MDA Clin Chimica Acta 2007
Oxidative Stress Antioxidants SOD &GSH-PX or Vit E, C & A Oxidants MDA
Oxidative Stress Inducers UV radiation Physical Exercise Smoking
Tobacco smoke contains gas and tar phase and other oxidants Induce OXIDATIVE STRESS
Smoking Moderate 11-20 Light 10 Heavy >20 Smokers (cigarettes/ day)
What is moderate exercise? moderate workout mild vigorous moderate-intensity walk corresponds to 100 steps/min or 3,000 steps/30 min It can be measured either by using pedometers or monitoring O 2 uptake during exercise in the lab Treadmill at speeds between 2.4 to 4.1 miles/h, the number of steps per min to reach moderate-intensity exercise for men was between 92 to 102 and for women it was between 91 to115 steps/ min
Analysis TBARS/UV MDA is a simple screnning method of oxidative damage which has been extensively used in smokers rough estimate of MDA TBARS/FL HPLC
Clinical Studies with serum MDA levels (µmol/l) using TBARS Total (n) Nonsmoker Smoker p Male (n) Female (n) TBARS 123 20.7 24.0 <0.01 107 14 UV 100 1.9 2.6 <0.001 50 50 UV 71 0.22 0.37 <0.05 48 23 FL TBARS/UV: Spectrophotometric detection of thiobarbituric acid reactive substances with UV/VIS detection TBARS/FL:Spectrofluorometric detection of thiobarbituric acid reactive substances (TBARS) with fluorescence detection Miller et al. Circulation 1997 Sharma et al. Ind J Med Res 2005 Kalra et al. Int J Exp Pathol 1991
Background
Background We have previously investigated temporal changes and/or daily fluctuations by determining indicators of lipid peroxidation such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), and malondialdehyde (MDA) levels in a small number of critically ill patients under oxidative stress versus healthy volunteers (as control) in order to design an effective antioxidant therapy regimen
MDA levels were significantly higher in the study group at 8 pm than that of control group (P<0.05), without significant difference within the 24 h period
Results Gunaydin et al. Minerva Anestesiol 2007 No significant differences were found in SOD and GSH-PX activities within the 24 h period or between the groups. GSH-PX activities in control and study groups revealed only temporal variation Consequently there are signs of oxidative stress in ICU patients that vary in time but further studies are required in order to design appropriate antioxidant treatments
Aim The aim of the present study is to investigate the acute effect of moderate exercise on oxidative stress by determining serum MDA levels in moderate smoker subjects versus nonsmokers
Patients and Methods 50 healthy subjects performing moderate intensity exercise were assigned to 2 groups Group 1 (n=25) moderate smokers (11-20 cigarettes/day) Group 2 (n=25) non-smokers were enrolled Sampling Venous blood samples were collected to determine MDA levels before & after moderate exercise
Biochemical Analysis MDA levels (as an indicator of lipid peroxidation) were detected in serum by TBARS/UV as described using the table Hunter et al. Neurochem Res 1985
Step 1 Calculations Std1 (20 nmol/ml)à 0,354 Std2 (10 nmol/ml)à 0,186 Std3 (5 nmol/ml)à 0,083 20/0,354=56,5 10/0,186=53,7 56,5 + 53,7 + 60,2 = 170,4 5/0,083=60,2 170,4/3=56,8 (common factor) Step 2 (Sample abs / Std abs) x std concentration = MDA (nmol/ml)
Statistical Analysis Results were expressed as mean±sd One-way ANOVA and unpaired t-test were used to assess differences between pre-exercise and post-exercise within smokers and non-smokers as well as between females and males p<0.05 was considered as statistically significant
Results Table 1. Demographic properties (mean±sd) Smoker (n=25) Non=smoker (n=25) Age (year) 34.0±0.8 32.8±1.0 BMI (kg/)cm 2 ) 24.9±0.9 22.9±1.2 Sex (male/female) 12/13 11/14 p>0.05
Results Table 2. Serum MDA levels in nmol/ml (mean±sd) Smoker (n=25) Non=smoker (n=25) Pre-exercise 3.98±0.23 2.05±0.75 Female 3.99±0.33 2.09±0.34 Male 3.97±0.22 2.01±0.44 Post-exercise 5.78±0.91* 3.25±0.88 Female 5.90±0.54# 3.20±0.65 Male 5.66±0.32 3.30±0.24 *:p<0.05 between pre-exercise vs post-exercise #:p<0.05 between female vs male
Discussion & Conclusion MDA detection in serum by TBARS, which is a simple and low cost analysis, appears to be positively correlated with smoking status in female subjects Therefore, MDA determinationcan be considered a valuable screening tool in demonstrating the oxidative stress due to moderate exercise particularly in smokers to reorganize healthier life style.
Thank you