The effect of curcumin supplementation on prooxidant/antioxidant balance, inflammation and exercise-induced muscle damage in physically active men.

INTERVENTION: This study is controlled, double‐blind, parallel intervention trial in healthy men (amateur long distance runners). The purpose of this intervention is to evaluate the effects of 2 g curcumin supplementation on prooxidant/antioxidant balance, inflammation and exercise‐induced muscle damage. The participants will take 2 capsules (500 mg each) of curcumin extract with piperine (Curcumin 500 max, Nanga, Zlotów, Poland) twice a day before meals, i.e. before breakfast and before dinner, drinking water, for a period of 6 weeks. According to the manufacturer's information, the content of the supplement capsule consists of: extract from long spurge standardised to 95% curcumin (500 mg) and extract from black pepper 95% (10 mg), an ingredient of the capsule (gelatin, purified water 13‐17%). The study will be conducted in two phases: ‐ in the first phase all subjects and will undergo assessment of body composition. Then all subjects will perform a running test with gradually increasing load on a moving treadmill. Blood for biochemical tests will be collected 3 times, i.e., before the start of the exercise test, 3‐5 minutes after its completion and at 1 hour post‐exercise restitution. The subjects will then be randomly divided into two groups: curcumin supplemented and placebo. ‐in the second phase of the study (6 weeks after starting the supplement or placebo), the subjects will again undergo assessment of baseline body composition and perform a running test as above. Blood for biochemical tests will be collected 3 times, i.e., before the start of the exercise test, 3‐5 minutes after its completion and at 1 hour post‐exercise restitution. CONDITION: Oxidative stress;Inflammation ;Muscle damage; ; Oxidative stress ; Inflammation ; Muscle damage Alternative and Complementary Medicine ‐ Herbal remedies Inflammatory and Immune System ‐ Normal development and function of the immune system Blood ‐ Normal development and function of platelets and erythrocytes PRIMARY OUTCOME: Individual VO2max will be determined by having; participants perform an incremental treadmill running test (a Cosmed treadmill, Germany).[After completion of anthropometric measurements at baseline, 6 weeks post‐commencement of intervention.] The body composition of the participants will be assessed by the bioimpedance method. [Baseline, 6 weeks post‐commencement of intervention.] INCLUSION CRITERIA: Inclusion criteria were healthy male and training experience of three years minimum. SECONDARY OUTCOME: Changes in myoglobin concentration in blood serum at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2) with using by the immunoenzymatic methods.[Baseline and 6 weeks post‐commencement of intervention. The biochemical tests will be performed after the end of the program.] Assesment of Sirtuin 3 level in blood serum at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2) with using by the immunoenzymatic methods.[Baseline and 6 weeks post‐commencement of intervention. The biochemical tests will be performed after the end of the program.] Assessment of muscle damage markers activity (CK, LDH) in blood plasma at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2) with using by the spectrophotometric methods.[After blood seperation, on the same day as blood collection at baseline and 6 weeks post‐commencement of intervention.] Changes in inflammatory markers (TNF‐alpha, CRP, IL‐1ß, IL‐6) in blood serum at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2) with using by the immunoenzymatic methods, excluding CRP which was measured by spectrophotometric method in an external laboratory. [Baseline and 6 weeks post‐commencement of intervention. The biochemical tests will be performed after the end of the program. ] Changes in markers of antioxidant status (SOD, CAT, GPx, GSH, UA, TAS) at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2). SOD, CAT, GPX will be analysed using spectrophotometric methods in erythrocythes. GSH will be measured in whole blood and UA in plasma samples using spectrophotometric method. TAS will be measured by a colorimetric method in blood serum. [Baseline and 6 weeks post‐commencement of intervention. The biochemical tests will be performed after the end of the program. ] Assessment of blood morphology using blood smear on the same day in each study phase (1 and 2) in external laboratory.[The biochemical tests will be performed after the collection of material at baseline and 6 weeks post‐commencement of intervention. ] Changes in aminotransferases (ALT, AST) concentration in blood serum at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2) with using by the spectrophotometric methods in external laboratory. [Baseline and 6 weeks post‐commencement of intervention. The biochemical tests will be performed after the end of the program.] Changes in markers of oxidative stress ( 8‐OHdG, MDA) concentration at rest, immediately after exercise, in 1h of restitution in each study phase (1 and 2) . The plasma malondialdehyde (MDA) concentration was determined by means of the thiobarbituric acid (TBARS) reaction. 8‐OHdG will be measured in serum samples using immunoenzymathic method.[Baseline and 6 weeks post‐commencement of intervention. The biochemical tests will be performed after the end of the program.]