Objective:To observe any effect of 12 weeks of moderate-intensity continuous training (MICT) and of high-intensity interval training (HIIT) on intestinal inflammation and the expression of α7 nicotinic acetylcholine receptor (α7nAChR) and nuclear factor kappa B p65 (NF-κΒp65) in rats fed a high-fat diet.Methods:Thirty-two healthy 5-week-old male Sprague-Dawley rats were divided at random into a normal diet and quiet group, a high-fat diet and quiet group, a high-fat diet MICT group, and a high-fat diet HIIT group, each of 8. The high-fat diet MICT group underwent continuous treadmill exercise at 70% of their maximum oxygen uptake (VO 2max), while the high-fat diet HIIT group did treadmill exercise at 40% to 45% of their VO 2max alternating with intervals at 95% to 99% of their VO 2max. The two quiet groups did no exercise. After 12 weeks, hematoxylin-eosin staining was used to observe the morphology of the rats′ intestinal tissue. Serum levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and free fatty acids (FFA) were determined, and immunofluorescence double labeling and western blotting were applied to detect the expression levels of α7nAChR, NF-κB p65 and tumor necrosis factor α (TNF-α) in the rats′ intestines. Results:Compared with the normal diet quiet group, the quiet group on a high fat diet had, on average, significantly heavier final body weights, lower total food intake, higher serum LDL, TG and FFA, lower HDL levels, and less protein expression of intestinal α 7nAChR. They showed higher average fluorescence intensity and expression of NF-κB p65 and TNF-α protein. Compared with the high-fat diet quiet group, the high-fat diet MICT and HIIT groups had significantly lighter final body weight, on average, lower total food intake, lower LDL and FFA levels and higher average fluorescence intensity. They showed significantly greater expression of α 7nAChR and NF-κB p65 protein, and lower expression of TNF-α protein. Compared with the high-fat diet MICT group, there was a significantly higher HDL content and lower average fluorescence intensity of NF-κ -Bp65 observed in the high-fat diet HIIT group. Moreover, reduced inflammatory infiltration, epithelial damage and mucosal crypt destruction were found in the colon tissue sections of both the high-fat diet MICT and HIIT groups.Conclusions:Twelve weeks of either MICT or HIIT can relieve intestinal inflammation resulting from a high-fat diet, at least in rats. The training increases the intestinal expression of α 7nAChR protein, and reduces the expression of NF-κBp65 and TNF-α. HIIT is superior to MICT in its effects.

Objective:To observe any effect of 12 weeks of moderate-intensity continuous training (MICT) and of high-intensity interval training (HIIT) on intestinal inflammation and the expression of α7 nicotinic acetylcholine receptor (α7nAChR) and nuclear factor kappa B p65 (NF-κΒp65) in rats fed a high-fat diet.Methods:Thirty-two healthy 5-week-old male Sprague-Dawley rats were divided at random into a normal diet and quiet group, a high-fat diet and quiet group, a high-fat diet MICT group, and a high-fat diet HIIT group, each of 8. The high-fat diet MICT group underwent continuous treadmill exercise at 70% of their maximum oxygen uptake (VO 2max), while the high-fat diet HIIT group did treadmill exercise at 40% to 45% of their VO 2max alternating with intervals at 95% to 99% of their VO 2max. The two quiet groups did no exercise. After 12 weeks, hematoxylin-eosin staining was used to observe the morphology of the rats′ intestinal tissue. Serum levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and free fatty acids (FFA) were determined, and immunofluorescence double labeling and western blotting were applied to detect the expression levels of α7nAChR, NF-κB p65 and tumor necrosis factor α (TNF-α) in the rats′ intestines. Results:Compared with the normal diet quiet group, the quiet group on a high fat diet had, on average, significantly heavier final body weights, lower total food intake, higher serum LDL, TG and FFA, lower HDL levels, and less protein expression of intestinal α 7nAChR. They showed higher average fluorescence intensity and expression of NF-κB p65 and TNF-α protein. Compared with the high-fat diet quiet group, the high-fat diet MICT and HIIT groups had significantly lighter final body weight, on average, lower total food intake, lower LDL and FFA levels and higher average fluorescence intensity. They showed significantly greater expression of α 7nAChR and NF-κB p65 protein, and lower expression of TNF-α protein. Compared with the high-fat diet MICT group, there was a significantly higher HDL content and lower average fluorescence intensity of NF-κ -Bp65 observed in the high-fat diet HIIT group. Moreover, reduced inflammatory infiltration, epithelial damage and mucosal crypt destruction were found in the colon tissue sections of both the high-fat diet MICT and HIIT groups.Conclusions:Twelve weeks of either MICT or HIIT can relieve intestinal inflammation resulting from a high-fat diet, at least in rats. The training increases the intestinal expression of α 7nAChR protein, and reduces the expression of NF-κBp65 and TNF-α. HIIT is superior to MICT in its effects.