| Popis: |
Radiotherapy, an established treatment of malignant diseases of the head and neck, increases the risk of chronic metabolic disorders. However, the molecular mechanisms responsible for metabolic dysfunction after irradiation remain unknown. We aimed to determine whether single head-neck irradiation intervention changes the levels of thyroid hormones and affects energy metabolism in high-fat diet mice and in chow diet mice. C57BL/6 mice were treated with a single dose of 6 Gy X-ray head-neck irradiation and were fed a high-fat diet. Body weight, accumulated food intake, fasting blood glucose and glucose tolerance were measured during the study. Plasma, brown adipose tissue, thyroid, liver and white adipose tissue were collected for histological analysis. We found that head-neck irradiation significantly increased food intake and decreased body weight in high-fat diet mice. However, there were no obvious changes in chow diet mice. Further studies showed that head-neck irradiation significantly increased levels of 3,5,3’-triiodothyronine and thyroid-stimulating hormone, as well as expression of uncoupling protein 1 in brown adipose tissue and glucose transporter 2 in liver in high-fat diet mice. Our results suggest that single head-neck irradiation intervention increases thyroid hormones levels and enhances energy metabolism in high-fat diet mice. |
