BACKGROUND:Studies have shown that cardiomyocyte apoptosis is closely related to cardiac decompensation and the cardiac aging process.Appropriate exercise can alter heart pump function in patients with heart failure as well as attenuate aging-induced cardiomyocyte apoptosis,hypertrophy,and fibrotic damage. OBJECTIVE:To investigate the effects of long-term aerobic exercise on cardiomyocyte apoptosis and the thioredoxin system in aging rats. METHODS:Thirty-six male Sprague-Dawley rats were selected and divided into three age groups:3-month-old young group,9-month-old middle-aged group,and 18-month-old elderly group,with 12 rats in each group.Within each age group,rats were randomly assigned to sedentary and exercise subgroups(n=6 per group).The sedentary groups did not undergo any exercise intervention.The exercise groups were acclimated to a treadmill environment and subsequently subjected to treadmill exercise for 45 minutes per day,at a speed of 15 m/min,5 days per week for 10 weeks in total.At 24 hours after the final intervention,ELISA was employed to measure serum levels of cardiac troponin I and creatine kinase-MB in rats.TUNEL assay was utilized to detect cardiomyocyte apoptosis,while western blot assay was employed to assess the protein expression of Bax,Bcl-2,Caspase 3,thioredoxin-1,thioredoxin-2,thioredoxin reductase-1,thioredoxin reductase-2,thioredoxin-interacting protein,apoptosis signal-regulating kinase 1,and P38 mitogen-activated protein kinase in rat myocardial tissue. RESULTS AND CONCLUSION:Serum levels of cardiac troponin I and creatine kinase-MB in the elderly sedentary group were significantly higher than those in the young and middle-aged sedentary groups and elderly exercise group(P<0.01).Serum levels of cardiac troponin I and creatine kinase-MB in the elderly sedentary group were significantly higher than those in the young and middle-aged exercise groups and elderly exercise group(P<0.01).Positive apoptotic cells in rat myocardial tissue,along with increased protein expression of Bax and Caspase 3,exhibited an age-related upward trend,while Bcl-2 protein expression showed a declining trend.In comparison with the sedentary groups within each age category,the number of apoptotic cardiomyocytes and the expression of Bax and Caspase 3 proteins were reduced to different degrees,and the expression of Bcl-2 protein was increased to different degrees in the corresponding exercise groups.Compared with the young sedentary group,middle-aged sedentary group and elderly exercise group,elderly sedentary rats showed a significant decrease in the expression of myocardial thioredoxin 1,thioredoxin 2,thioredoxin reductase 1,and thioredoxin reductase 2 proteins(P<0.05,P<0.01).The expression of myocardial thioredoxin 1,thioredoxin 2,and thioredoxin reductase 2 proteins was lower in the elderly exercise group than in the young exercise group(P<0.05,P<0.01),while the expression of thioredoxin reductase 1 and thioredoxin reductase 2 proteins was lower in the elderly exercise group than in the middle-aged exercise group(P<0.01).The protein expression of thioredoxin-interacting protein,apoptosis signal-regulating kinase 1,and P38 mitogen-activated protein kinase in rat myocardium was significantly higher in the elderly sedentary group than the young sedentary group,middle-aged sedentary group and elderly exercise group(P<0.01).The protein expression of thioredoxin-interacting protein,apoptosis signal-regulating kinase 1,and P38 mitogen-activated protein kinase in rat myocardium was significantly higher in the elderly exercise group than the young exercise group and middle-aged exercise group(P<0.01).To conclude,aerobic exercise may enhance the anti-apoptotic effects of thioredoxin by down-regulating the expression of thioredoxin-interacting protein in aging rat hearts,leading to the downregulation of apoptosis signal-regulated kinase 1 and P38 mitogen-activated kinase protein,thereby alleviating myocardial cell apoptosis in aging rat hearts.

Objective:To explore the effects of bariatric metabolic surgery on body composition.Methods:The retrospective cohort study was conducted. The clinicopathological data of 66 patients with metabolic diseases who were admitted to the Third Xiangya Hospital of Central South University from January 2013 to December 2014 were collected. There were 42 males and 24 females, aged (40±11)years, with a range from 17 to 63 years. Of the 66 patients, 27 undergoing laparoscopic sleeve gastrectomy (LSG) and 39 undergoing laparoscopic Roux-en-Y gastric bypass (LRYGB) were allocated into LSG group and LRYGB group, respectively. The body composition of all patients was determined by dual-energy X-ray absorptiometry at preoperation and postoperative 6 months. Observation indicators: (1) the changes of anthropometric parameters, glucolipid metabolism, body fat mass percentage (BF%) and the ratio of Android BF% and Gynoid BF% (A/G ratio) from preoperation to postoperative 6 months; (2) the changes of whole and local body composition from preoperation to postoperative 6 months; (3) analysis of the correlation between BF% and anthropometric parameters, glucolipid metabolism. (4) Follow-up. Follow-up was conducted using outpatient or hospitalization examination to detect the changes of body composition at the time of postoperative 6 month. The follow-up time was up to July 2015. Measurement data with normal distribution were represented as Mean± SD, paired-samples t test was used for intra-group comparison, and independent-samples t test when baseline data were consistency or covariance analysis when baseline data were not consistency was used for inter-group comparison. Measurement data with skewed distribution were represented as M ( P25, P75), and comparison between groups was analyzed using Wilcoxon signed rank test. The correlation test was undertaken with the Pearson bivariate analysis. Results:(1) The changes of anthropometric parameters, glucolipid metabolism, BF% and A/G ratio from preoperation to postoperative 6 months: for patients in the LSG group, the body mass, body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), diastolic blood pressure (DBP), systolic blood pressure (SBP), fasting plasma glucose (FPG), HbA1c, high density lipoprotein cholesterol (HDL-C), triglyceride (TG), whole BF%, arms BF%, legs BF%, trunk BF%, Android BF%, Gynoid BF% and A/G ratio at preoperation and postoperative 6 months were (102±17)kg, (37±5)kg/m 2, (118±14)cm, 1.01±0.06, (94±14)mmHg(1 mmHg=0.133 kPa), (137±15)mmHg, (8.1±4.2)mmol/L, 7.3%±2.4%, (1.11±0.26)mmol/L, 2.14 mmol/L(1.73 mmol/L, 2.59 mmol/L), 40%±6%, 46%±10%, 36%±8%, 42%±6%, 45%±6%, 37%±7%, 1.23±0.18 and (82±15)kg, (29±4)kg/m 2, (101±13)cm, 0.95±0.08, (76±10)mmHg, (118±16)mmHg, (7.2±1.2)mmol/L, 5.4%±0.8%, (1.26±0.32)mmol/L, 1.21 mmol/L(0.88 mmol/L, 1.55 mmol/L), 36%±8%, 41%±9%, 34%±10%, 38%±8%, 41%±8%, 35%±10%, 1.20±0.17, respectively. There was no significant difference in the intra-group comparison of the Gynoid BF% and A/G ratio ( t=1.903, 1.730, P>0.05) and there were significant differences in the intra-group comparison of the rest of above indicators ( t=12.748, 13.283, 9.013, 3.804, 6.031, 6.226, 2.393, 4.287, -2.900, 3.193, 2.932, 5.198, 2.167, 3.357, 3.116, P<0.05). For patients in the LRYGB group, the body mass, BMI, WC, WHR, DBP, SBP, FPG, HbA1c, HDL-C, TG, whole BF%, arms BF%, legs BF%, trunk BF%, Android BF%, Gynoid BF% and A/G ratio at preoperation and postoperative 6 months were (80±12)kg, (28±4)kg/m 2, (98±9)cm, 0.96±0.05, (85±10)mmHg, (134±17)mmHg, (8.6±2.8)mmol/L, 8.3%±1.7%, (1.13±0.26)mmol/L, 2.06 mmol/L(1.15 mmol/L, 3.30 mmol/L), 30%±8%, 29%±11%, 23%±9%, 37%±7%, 40%±7%, 29%±8%, 1.42±0.26 and (69±9)kg, (24±3)kg/m 2, (91±8)cm, 0.93±0.05, (80±9)mmHg, (129±18)mmHg, (7.4±1.8)mmol/L, 7.0%±1.5%, (1.18±0.29)mmol/L, 1.29 mmol/L(0.85 mmol/L, 2.02 mmol/L), 25%±8%, 23%±12%, 20%±9%, 29%±9%, 32%±10%, 25%±9%, 1.29±0.25, respectively. There was no significant difference in the intra-group comparison of the SBP and HDL-C ( t=1.733, -1.073, P>0.05) and there were significant differences in the intra-group comparison of the rest of above indicators ( t=10.525, 10.200, 7.129, 2.887, 2.805, 2.517, 3.699, 2.608, 7.997, 8.018, 6.029, 8.342, 8.069, 5.813, 6.391, P<0.05). There were significant differences in DBP, SBP, HbA1c, trunk BF%, Android BF% and A/G ratio at postoperative 6 months between LSG group and LRYGB group ( F=6.408, t=2.641, F=20.673, 5.140, 5.735, 4.714, P<0.05). (2) The changes of whole and local body composition from preoperation to postoperative 6 months: for patients in the LSG group, the whole fat mass, muscle mass, fat-free mass at preoperation and postoperative 6 months were (38.74±9.68)kg, (57.71±11.62)kg, (60.14±11.95)kg and (26.64±8.29)kg, (48.65±13.80)kg, (51.00±14.27)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=5.256, 5.413, 5.315, P<0.05); the arms fat mass, muscle mass, fat-free mass were (5.19±1.67)kg, (5.78±1.58)kg, (6.10±1.64)kg and (3.73±1.19)kg, (5.10±1.53)kg, (5.43±1.57)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=7.564, 5.405, 5.363, P<0.05); the legs muscle mass and fat-free mass were (19.05±4.19)kg, (19.93±4.35)kg and (15.93±4.71)kg, (16.81±4.87)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=5.623, 5.568, P<0.05); the trunk fat mass and fat-free mass were (21.93±4.90)kg, (29.7±5.94)kg and (14.69±4.79)kg, (24.78±7.02)kg respectively, showing significant differences in the intra-group comparison of the above indicators ( t=8.903, 5.421, P<0.05); the Android fat mass and fat-free mass were (4.16±1.19)kg, (5.01±1.12)kg and (2.57±0.90)kg, (3.83±1.20)kg respectively, showing significant differences in the intra-group comparison of the above indicators ( t=8.288, 7.637, P<0.05); the Gynoid fat mass and fat-free mass were (5.51±1.42)kg, (9.27±1.86)kg and (3.85±1.16)kg, (7.65±2.31)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=7.461, 5.672, P<0.05); the skeletal muscle index were (8.86±1.38)kg/m 2 and (7.49±1.71)kg/m 2, respectively, showing a significant differences in the intra-group comparison ( t=5.724, P<0.05). For patients in the LRYGB group, the whole fat mass, muscle mass, bone mineral content, fat-free mass at preoperation and postoperative 6 months were (23.58±7.80)kg, (51.76±8.35)kg, (2.55±0.48)kg, (54.31±8.63)kg and (16.88±6.86)kg, (49.41±7.70)kg, (2.47±0.50)kg, (51.88±8.05)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=9.001, 3.974, 4.354, 4.075, P<0.05); the arms fat mass were (2.72±2.37)kg and (1.73±1.02)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=3.470, P<0.05); the legs fat mass, muscle mass, fat-free mass were (5.21±2.46)kg, (16.68±3.50)kg, (17.60±3.66)kg and (4.01±2.12)kg, (15.63±2.90)kg, (16.54±3.05)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=6.592, 3.372, 3.319, P<0.05); the trunk fat mass were (14.87±4.11)kg and (10.38±4.00)kg, respectively, showing a significant difference in the intra-group comparison of the above indicators ( t=8.431, P<0.05); the Android fat mass and fat-free mass were (2.61±0.86)kg, (3.96±0.87)kg and (1.81±0.79)kg, (3.78±0.67)kg respectively, showing significant differences in the intra-group comparison of the above indicators ( t=8.032, 2.153, P<0.05); the Gynoid fat mass and fat-free mass were (3.14±1.17)kg, (7.89±1.58)kg and (2.44±0.96)kg, (7.43±1.26)kg, respectively, showing significant differences in the intra-group comparison of the above indicators ( t=6.112, 3.207, P<0.05); the skeletal muscle index were (8.04±1.22)kg/m 2 and (7.43±1.13)kg/m 2, respectively, showing significant differences in the intra-group comparison ( t=4.953, P<0.05). There were significant differences in whole muscle mass, whole fat-free mass, arms fat mass, legs muscle mass, legs fat-free mass, trunk fat-free mass, Android fat-free mass, Gynoid fat-free mass and skeletal muscle index at postoperative 6 months between LSG group and LRYGB group ( F=13.846, 13.614, 23.696, 7.100, 7.127, 15.243, 16.921, 8.625, 5.497, P<0.05). (3) Analysis of the correlation between BF% and anthropometric parameters, glucolipid metabolism: the whole BF% of 66 patients was positively correlated with body mass, BMI, WC and WHR ( r=0.405, 0.663, 0.625, 0.331, P<0.05); the arms BF% was positively correlated with body mass, BMI, WC and WHR ( r=0.432, 0.682, 0.639, 0.309, P<0.05); the legs BF% was positively correlated with body mass, BMI and WC ( r=0.366, 0.646, 0.564, P<0.05); the trunk BF% was positively correlated with body mass, BMI, WC and WHR ( r=0.332, 0.560, 0.554, 0.335, P<0.05); the Android BF% was positively correlated with body mass, BMI, WC and WHR ( r=0.327, 0.537, 0.543, 0.336, P<0.05); the Gynoid BF% was positively correlated with BMI and WC ( r=0.561, 0.488, P<0.05), and negatively correlated with FPG ( r=-0.491, P<0.05); the A/G ratio was negatively correlated with BMI ( r=-0.334, P<0.05), and positively correlated with FPG ( r=0.506, P<0.05); the skeletal muscle index was positively correlated with body mass, BMI, WC and WHR ( r=0.757, 0.641, 0.609, 0.519, P<0.05), and negatively correlated with HDL-C ( r=-0.369, P<0.05). (4) Follow-up: 66 patients were followed up at the time of postoperative 6 month. Conclusions:Both LSG and LRYGB significantly change body composition. LRYGB is superior to LSG in reducing trunk BF% and Android BF%. The effects of the two surgical methods on fat mass and bone mineral content are similar. LSG lead to a more significant decrease in whole muscle mass, and LRYGB lead to a more significant decrease in legs muscle mass and skeletal muscle index.