Pereira B, Rosa L F, Safi D A, Bechara E J, Curi R
Department of Biochemistry, Universidade de São Paulo, Brazil.
J Endocrinol. 1994 Jan;140(1):73-7. doi: 10.1677/joe.0.1400073.
This study examined the effect of experimental hyper- and hypothyroidism on the superoxide dismutase, catalase and glutathione peroxidase activities of rat lymphoid organs (mesenteric lymph nodes, spleen and thymus) and muscles (soleus and gastrocnemius-white portion) for comparison. The capacity for the generation of reducing equivalents was also investigated: activities of glucose-6-phosphate dehydrogenase (pentose-phosphate pathway) and citrate synthase (Krebs cycle). Hyperthyroidism tended to enhance lipid peroxide content in all tissues. This effect may result from (1) a high capacity for the generation of reducing equivalents in cytosol and mitochondria and (2) a reduced activity of catalase in the lymphoid organs and of glutathione peroxidase in the muscles. The process of lipid peroxidation in these tissues caused by hyperthyroidism was probably slowed down by the augmentation of CuZn- and Mn-superoxide dismutase (Mn-SOD) activities observed under this condition. Hypothyroidism tended to diminish lipid peroxidation and did not affect citrate synthase and glucose-6-phosphate dehydrogenase activities in the lymphoid organs and muscles. Low levels of thyroid hormones tended to diminish Mn-SOD and glutathione peroxidase activities. These findings show that the thyroid hormones might be able to regulate the activities of CuZn- and Mn-SOD, and catalase and glutathione peroxidase in the lymphoid organs and skeletal muscles.
本研究检测了实验性甲状腺功能亢进和减退对大鼠淋巴器官（肠系膜淋巴结、脾脏和胸腺）及肌肉（比目鱼肌和腓肠肌白色部分）中超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性的影响，以作比较。还研究了还原当量的生成能力：葡萄糖-6-磷酸脱氢酶（戊糖磷酸途径）和柠檬酸合酶（克雷布斯循环）的活性。甲状腺功能亢进往往会提高所有组织中的脂质过氧化物含量。这种影响可能源于：（1）胞质溶胶和线粒体中还原当量的高生成能力，以及（2）淋巴器官中过氧化氢酶活性降低和肌肉中谷胱甘肽过氧化物酶活性降低。在这种情况下观察到的铜锌超氧化物歧化酶（CuZn-SOD）和锰超氧化物歧化酶（Mn-SOD）活性增强，可能减缓了甲状腺功能亢进导致的这些组织中的脂质过氧化过程。甲状腺功能减退往往会减少脂质过氧化，并且不影响淋巴器官和肌肉中柠檬酸合酶和葡萄糖-6-磷酸脱氢酶的活性。低水平的甲状腺激素往往会降低Mn-SOD和谷胱甘肽过氧化物酶的活性。这些发现表明，甲状腺激素可能能够调节淋巴器官和骨骼肌中CuZn-SOD、Mn-SOD、过氧化氢酶和谷胱甘肽过氧化物酶的活性。
