TMT Labeling Reveals the Effects of Exercises on the Proteomic Characteristics of the Subcutaneous Adipose Tissue of Growing High-Fat-Diet-Fed Rats

Growing period is an important period for fat remodeling. High-fat diet and exercise are reasons for adipose tissue (AT) remodeling, but existing evidence is not enough. Therefore, the effects of moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT) on the proteomic characteristics of the subcutaneous AT of growing rats on normal diet or high-fat diet (HFD) were determined.

The exercise stress response in the growing period was stronger but increased the energy metabolism and metabolism. MICT and HIIT can reduce fat, increase muscle percentage, and improve maximum oxygen uptake in rats fed with HFD. However, in rats with normal diet, MICT and HIIT triggered more immune responses of sWAT, especially HIIT. In addition, spliceosomes may be the key factors in AT remodeling triggered by exercise and diet.

Four-week-old male Sprague-Dawley rats (n = 48) were subdivided into six groups: normal diet control group, normal diet-MICT group, normal diet-HIIT group, HFD control group, HFD-MICT group, and HFD-HIIT group. Rats in the training group ran on a treadmill 5 days a week for 8 weeks (MICT: 50 min at 60-70% VO2max intensity; HIIT: 7 min of warm-up and recovery at 70% VO2max intensity, 6 sets of 3 min of 30% VO2max followed by 3 min 90% VO2max). Following physical assessment, inguinal subcutaneous adipose tissue (sWAT) was collected for proteome analysis using tandem mass tag labeling.

MICT and HIIT attenuated body fat mass and lean body mass but did not affect weight gain. Proteomics revealed the impact of exercise on ribosome, spliceosome, and the pentose phosphate pathway. However, the effect was reversed on HFD and normal diet. The differentially expressed proteins (DEPs) affected by MICT were related to oxygen transport, ribosome, and spliceosome. In comparison, the DEPs affected by HIIT were related to oxygen transport, mitochondrial electron transport, and mitochondrion protein. In HFD, HIIT was more likely to cause changes in immune proteins than MICT. However, exercise did not seem to reverse the protein effects of HFD.