RESUMO
Objective@#To examine the effects of high intensity interval training (HIIT) on body composition and cardiorespiratory fitness of obese primary school students, so as to provide a theoretical basis and practical reference for HIIT exercise prescription in schools.@*Methods@#From August to December 2022, 25 obese children [age:(11.0±0.4)years, BMI:(23.3±0.8)kg/m 2] from a primary school in Shenzhen were recruited and divided into an exercise group ( n =13) and a control group ( n =12). After 12 weeks of exercise intervention [The durations of load period and intermittent period were 15 s, load exercise intensity was 100% maximal aerobic speed (MAS), and intermittent exercise intensity was 50% MAS, each time there were 2 groups× 8 rounds, and the rest between groups was 2 minutes, totaling 10 minutes, and 20 meter shuttle run test (20 m-SRT) was performed once every 4 weeks to adjust and update MAS], the changes in body composition and cardio respiratory fitness indexes of obese subjects before and after the intervention were compared.@*Results@#After the intervention, body weight, BMI, body fat, body fat percentage, and visceral adipose tissue area of obese subjects in the exercise group decreased from (55.6±6.2)kg, (22.7±0.6)kg/m 2, (41.8±6.9)kg, ( 23.4± 5.5)% and (102.4±39.0)cm 2 to (52.3±5.8)kg, (21.1±0.8)kg/m 2, (38.6±6.3)kg, (20.2±4.5)% and (84.2±26.9)cm 2, respectively( t =8.73, 10.96, 7.02, 4.92, 4.95, P <0.05). SBP decreased from (115.4±9.7)mmHg to (112.3±8.7)mmHg ( t = 2.96 , P <0.05). The content of skeletal muscle, 20 m-SRT and VO 2max increased from (21.3±5.3)kg, (21.6±4.9) times and (39.4±2.0)mL/(kg ·min) to (21.8±5.2)kg, (31.4±6.3)times and (43.6±2.6)mL/(kg ·min), respectively ( t =-3.33, -8.37, -10.56 , P <0.05).@*Conclusions@#HIIT is an effective way to improve the body composition and cardiorespiratory fitness of obese primary school students. It is recommended that schools with the necessary conditions use this method as an intervention measure to help reduce weight and improve cardiovascular health among obese students.
RESUMO
Pancreatic cancer is well known to be the most deadly malignancy with the worst survival rate of all cancers. High temperature requirement factor A1 (HtrA1) plays an important role in cancer cell proliferation, migration, apoptosis, and differentiation. This study aimed to explore the function of HtrA1 in pancreatic cancer cell growth and its underlying mechanism. We found that the expression of HtrA1 was lower in pancreatic cancer tissue compared to the adjacent normal tissue. Consistently, HtrA1 levels were also decreased in two human pancreatic cancer cell lines, PANC-1 and BXPC-3. Moreover, enforced expression of HtrA1 inhibited cell viability and colony formation of PANC-1 and BXPC-3 cells. Overexpression of HtrA1 promoted apoptosis and suppressed migratory ability of tumor cells. On the contrary, siRNA-mediated knockdown of HtrA1 promoted the growth potential of pancreatic cancer cells. In addition, we found that up-regulation of HtrA1 reduced the expression of Notch-1 in pancreatic cancer cells. On the contrary, knockdown of HtrA1 increased the expression levels of Notch-1. Furthermore, overexpression of Notch-1 abolished the anti-proliferative effect of HtrA1 on pancreatic cancer cells. Taken together, our findings demonstrated that HtrA1 could inhibit pancreatic cancer cell growth via regulating Notch-1 expression, which implied that HtrA1 might be developed as a novel molecular target for pancreatic cancer therapy.