BACKGROUND: Studies have suggested that endoplasmic reticulum stress is involved in the process of diabetic peripheral neuropathy, and improving the state of endoplasmic reticulum stress can reduce the degree of diabetic peripheral neuropathy. Whether exercise has a positive effect on endoplasmic reticulum stress in diabetic peripheral nerves is rarely documented. OBJECTIVE: To observe the effects of aerobic and resistance exercise on the expression of Grp78, Chop and Caspase-12 in the endoplasmic reticulum stress signal pathway in the sciatic nerve of type 2 diabetic mellitus (T2DM) rats. METHODS: Sixty Sprague-Dawley male rats were divided into normal control group (normal diet, n=24) and T2DM model group (n=36). Rats in the T2DM model group were fed with high-fat and high-sugar diet for 8 weeks to establish T2DM models. Rats in the normal control group were randomly subdivided into quiet control group, aerobic exercise group and resistance exercise group, while those in the T2DM model group were randomized into quiet T2DM group, T2DM aerobic exercise group, and T2DM resistance exercise group. Aerobic and resistance exercises in corresponding groups lasted for 8 weeks. After 8 weeks exercise, fasting blood glucose, insulin level, insulin resistance index, mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured. The structural changes of the sciatic nerve were observed by transmission electron microscope. The expression levels of Grp78, Chop and Caspase-12 in the sciatic nerve were detected by western blot. An ethic approval was obtained from the Animal Experimental Ethics Committee of Chengdu Sport University (approval No. 2018024A). RESULTS AND CONCLUSION: After 8 weeks of exercise, compared with the quiet control group, fasting blood glucose and HOMA-IRI in all T2DM rats increased significantly (P < 0.01). Compared with the quiet T2DM group, fasting blood glucose and insulin resistance index in the two T2DM exercise groups were significantly reduced (P < 0.01), while fasting blood glucose in the T2DM resistance exercise group was significantly lower than that of T2DM aerobic exercise group (P < 0.05). Compared with the quiet control group, the structure of the sciatic nerve in all T2DM rats showed typical demyelination changes, including disordered and loose myelin sheath arrangement, lamellar separation and shrinkage. Compared with the quiet T2DM group, the two T2DM groups had tighter myelin structure of the sciatic nerve and milder lamellar separation. Compared with the quiet control group, the MWT and TWL in the quiet T2DM group and T2DM resistance exercise group declined significantly (P < 0.01), whereas the TWL in the T2DM aerobic exercise group was significantly higher than that in the T2DM resistance exercise group (P < 0.05). Compared with the quiet control group, the expression of Grp78, Chop, and Caspase-12 in the quiet T2DM group was significantly increased (P < 0.01). Compared with the quiet T2DM group, the expression of Grp78, Chop, and Caspase-12 in the T2DM aerobic exercise group was significantly decreased (P < 0.01; P < 0.05). The expression of Grp78 and Caspase-12 in the T2DM resistance exercise group was significantly higher than that in the T2DM aerobic exercise group (P < 0.05). To conclude, endoplasmic reticulum stress in the peripheral nerve of diabetic rats results in demyelination of peripheral nerve and decrease of MWT and TWL in diabetic rats. Both aerobic exercise and resistance exercise can reduce the endoplasmic reticulum stress in the peripheral nerve of diabetic rats, and improve the structure and function of the sciatic nerve. Moreover, the effect of aerobic exercise on the endoplasmic reticulum stress is better than that of resistance exercise.

OBJECTIVE: To explore the expression and significance of Eotaxin and RANTES in the rat model of allergic rhinitis (AR). METHOD: 20 female SD rats in 6-7 weeks were randomly divided into control group and AR group (n = 10, respectively). AR rat model was made with ovalbumin stimulation. To detect pathological changes in mucosa and chemokine Eotaxin, RANTES in their nasal and lung tissues after execution. RESULT: Compared with the control group, Lung EOS cell counted higher in AR group and the difference was significant (P < 0.01); the AR rats nasal mucosa and lung tissue of Eotaxin, RANTES expression was significantly increased (P < 0.01). CONCLUSION There exist high expression of Eotaxin, RANTES, infiltration of eosinophils in nasal and lung tissue of model rats with allergic rhinitis, inferring that the upper and lower respiratory tract inflammatory response has obvious consistency.
Animals ; Chemokine CCL11 ; metabolism ; Chemokine CCL5 ; metabolism ; Disease Models, Animal ; Female ; Lung ; metabolism ; Nasal Mucosa ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic ; metabolism

Objective:To investigate the efficacy and mechanism of static progressive stretch (SPS) with different parameters in the treatment of stiff knee in rats.Methods:Fifty-six male 8-week SD rats were randomly divided into an operation group ( n=48) and a blank group ( n=8, normal feeding rats without any treatment). The knee joints of the rats in the operation group were fixed with Kirschner wire for 4 weeks to create models of right knee flexion stiffness. The 42 rats with successful modeling were randomly divided into 6 groups ( n=7): the model group was executed and sampled after successful modeling, the spontaneous recovery group was not given any treatment after successful modeling, group T1 was given SPS treatment for 20 min once per day, group T2 was given SPS treatment for 30 min once per day, group T3 was given SPS treatment for 20 min once every 2 days, and group T4 was given SPS treatment for 30 min once every 2 days. After 16 days, the range of knee motion, number of myofibroblasts, and positive proportion of transforming growth factor- β1 (TGF- β1) in the joint capsule were detected and compared between groups. Results:The ranges of knee motion in the spontaneous recovery group and the 4 SPS treatment groups were significantly greater than those before treatment ( P<0.05), and the improvements in the range of knee motion in the 4 SPS treatment groups were significantly greater than that in the spontaneous recovery group ( P<0.05). The range of knee motion in group T2 (112.29°±1.89°) was improved the most significantly. The number of myofibroblasts was (23.72±10.75)/HP, which was significantly smaller than that in T3 group [(55.72±33.56)/HP] or in T4 group [(50.72±33.34)/HP] ( P<0.05). The positive proportions of TGF- β1 in the joint capsule in the 4 SPS treatment groups were significantly lower than that in the model group, and the positive proportion of TGF- β1 in the joint capsule in group T2 (0.51%±0.38%) was significantly lower than those in group T3 and T4 ( P<0.05). Conclusions:As SPS treatment can reduce the expression of TGF- β1 in the joint and inhibit the excessive proliferation of myofibroblasts to alleviate the pathological changes in a stiff knee, it has a significant effect on the stiff knee in rats. The SPS treatment for 30 minutes and once per day may lead to the best efficacy.