A Comparison of the Effects of Resistance and Endurance Training Protocols on Serum Irisin Level and Alkaline Phosphatase Activity in Sedentary Obese Women

Introduction. Studies have revealed that the anabolic effect of irisin on bone is mediated by an increase in alkaline phosphatase. However, few studies have investigated the interactive effect of irisin on alkaline phosphatase after exercise training. Therefore, the present study aimed to compare the impact of endurance and resistance training protocols on serum irisin concentration and total alkaline phosphatase activity in sedentary obese women. Material and methods. Forty-five sedentary obese women (age: 48.96 ± 5.2 years, body mass index 32.24 ± 3.76 kg/m2) were randomly assigned to control, endurance, and resistance groups. Endurance (45 to 75 minutes at an intensity corresponding to 50 to 80% of heart rate reserve) and resistance exercise training (3 sets, 10-15 repetitions at an intensity corresponding to 50 to 65% of one-repetition maximum) were conducted for 8 weeks, 3 days per week. Maximal oxygen consumption (VO2max) was estimated using the modified Bruce protocol treadmill test. Fasting blood samples were taken before the first and 48-hr after the last exercise training sessions. The serum concentrations of irisin and total alkaline phosphatase activity were measured using the sandwich ELISA method and photo-metric method, respectively. Results. Both endurance and resistance exercise training protocols caused a significant reduction in BMI and BFP of obese women. In contrast, VO2max significantly increased after both exercise training protocols. However, neither endurance nor resistance training protocols had a significant impact on the serum concentrations of irisin and total alkaline phosphatase activity. No significant inter-group differences were observed between the subjects’ BMI, BFP, VO2max, total alkaline phosphatase, and irisin at the end of protocols. Conclusions. The finding of the current study revealed that neither of the training protocols had a significant impact on bone anabolic parameters. However, performing these types of exercise is suggested for weight management in obese women.

Abnormalities in serum biomarkers correlate with lower cardiac index in the Fontan population

BackgroundFontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients.Methods and resultsThis study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman’s Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6–33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (−0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (−0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63–0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2versus lower-risk group=2.96 L/minute/m2, (p<0.01)].ConclusionsHigher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.