RESUMEN
The study investigated the effect of high- and low-intensity exercise training on inflammatory reaction of blood and skeletal muscle in streptozotocin (STZ)-induced diabetic male Sprague-Dawley rats (243 ± 7 g, 8 weeks). The rats completed treadmill running in either high-intensity exercise (6 weeks of exercise training, acute bouts of exercise) or low-intensity exercise (6 weeks of exercise training). Non-running, sedentary rats served as controls. To induce diabetes mellitus, rats received a peritoneal injection of STZ (50 mg · kg(-1)). Rats were sacrificed immediately after an acute bout of exercise and 6 weeks of exercise training. Inflammatory factors were analyzed by ELISA and by immune blotting from the soleus and extensor digitorum longus muscles. In the serum, inflammatory cytokines (IL-1ß, TNF-α, IL-6, IL-4) and reactive oxygen species (ROS) (nitric oxide and malondialdehyde) increased in diabetic rats. However, all exercise training groups displayed reduced inflammatory cytokines and reactive oxygen species. In skeletal muscles, low-intensity exercise training, but not high intensity exercise, reduced the levels of COX-2, iNOS, and MMP-2, which were otherwise markedly elevated in the presence of STZ. Moreover, the levels of GLUT-4 and MyoD were effectively increased by different exercise intensity and exercise duration. Low-intensity exercise training appeared most effective to reduce diabetes-related inflammation. However, high-intensity training also reduced inflammatory factors in tissue-specific muscles. The data implicate regular exercise in protecting against chronic inflammatory diseases, such as diabetes.
RESUMEN
BACKGROUND: The presence and extent of osteolytic bone lesions in untreated patients with multiple myeloma are important factors in the staging of the disease, and the extent of bone lesions in multiple myeloma cases significantly influences decisions regarding therapy. Recently, fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) have been used to detect bone marrow involvement in patients with multiple myeloma. PURPOSE: To compare the efficacy of FDG-PET and MRI for the detection of bone marrow infiltration into the spine in untreated patients with multiple myeloma. MATERIAL AND METHODS: Twenty-two patients with multiple myeloma underwent both FDG-PET and spine MRI. The examined spinal regions by MRI included 21 thoracic and lumbar spines, one lumbar spine, and 12 cervical spines. The following imaging sequences were performed: T1-weighted spin-echo MRI with and without fat suppression, and T2-weighted spin-echo MRI in the sagittal plane. In the patients with bone marrow abnormalities, an additional contrast-enhanced T1-weighted spin-echo MR image and a fat-suppressed T1-weighted spin-echo MR image were obtained. Patients were divided into three groups on the basis of the criteria defined by Durie and Salmon: stage I (n=9), stage II (n=3), and stage III (n=10). The number and location of lesions detected in both FGD-PET and MRI were recorded, and the lesions were compared using the McNemar test. Bone marrow biopsy results, the patient's clinical examinations, and other imaging findings (MRI, FDG-PET, etc.) were used as references. RESULTS: In stages I and II (37 lesions in 12 patients), FDG-PET and MRI detected lesions in 78% (29 of 37 lesions) and 86% (32 of 37 lesions), respectively. However, the difference between the abilities of FDG-PET and MRI to detect lesions was not statistically significant (P=0.317). In stage III (101 lesions in 10 patients), FDG-PET and MRI detected lesions in 80% (81 of 101 lesions) and 92% (93 of 101 lesions), respectively. The difference between the abilities of FDG-PET and MRI to detect lesions was statistically significant (P=0.038). CONCLUSION: MRI is superior to FDG-PET in detecting bone marrow involvement in the spine of patients with advanced multiple myeloma.
