Metformin inhibits the growth of anaplastic thyroid cancer cell by miRNA/mTOR pathway / 中华内分泌代谢杂志

Objective To investigate the effect of metformin on the growth of human anaplastic thyroid cancer cell HTh74Rdox which is doxorubicin resistant. Methods The HTh74Rdox was treated with different concentrations of metformin for 48 h. Cell morphology was observed by microscope, cell viability was tested by methylthiazoletetrazolium (MTT), cell apoptosis by annexin Ⅴ and propidium iodide double staining, the anti-oncogenic miRNA was assayed by realtime fluorescence quantitative PCR (RT-PCR), and the adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway tested by western blot. Furthermore, the anti-oncogenic miRNAs were knockdown by miRNA inhibitors (miR-34a, miR-101, miR-125b, and miR-138 inhibitors) and the cells were treated by metformin for 48 h, after that, cell apoptosis was detected by annexin Ⅴ and propidium iodide double staining, the expression of protein related to AMPK/mTOR signaling pathway was detected by western blot. Results Metformin inhibited the growth of human anaplastic thyroid cancer cell HTh74Rdox in a concentration-dependent manner, the cell apoptosis was induced by metformin, and there was a significantly lower expression of miR-34a, miR-101, miR-125b, and miR-138 in the HTh74Rdox. However, the four above miRNAs were upregulated by metformin, and AMPK/mTOR pathway was also activated by metformin. When these miRNAs were suppressed by miR-inhibitors (miR-34a, miR-101, miR-125b, miR-138 inhibitors), the stimulating effect of apoptosis and AMPK/mTOR pathway by metformin were reversed. Conclusion Metformin significantly suppresses cell viability of human anaplastic thyroid cancer cell HTh74Rdox, and stimulates AMPK/mTOR pathway and apoptosis by upregulating the expressions of miR-34a, miR-101, miR-125b, miR-138 in HTh74Rdox cell.

Daily calorie restriction and alternate day fasting for type 2 diabetes prevention / 中华内分泌代谢杂志

[Summary] Lifestyle intervention is one of the important strategies for the prevention of type 2 diabetes. Recently, caloric restriction regimen has become a hot topic as one of the cornerstone of lifestyle intervention. The alternate day fasting regimen is simple, and increases the patient compliance. Both daily calorie restriction and alternate day fasting regimen can reduce body-weight significantly in pre-diabetes subjects, and reduce the visceral fat mass and the fasting insulin levels, and improve the insulin sensitivity, as well as maintain the lean mass, though the effect on fasting blood glucose was not significant. Nevertheless, the most recent studies have demonstrated that daily calorie restriction,in particular, alternate day fasting regimens can be effective in individuals with pre-diebates in order to prevent type 2 diabetes.

Replacement therapy of hypothyroidism: Whether the use of levothyroxine is adequate? / 中华内分泌代谢杂志

Hypothyroidism is a common endocrine disease.Its treatment depends on thyroid hormone replacement therapy.Currently,levothyroxine (L-T4) is the preparation recommended by many guidelines.However,there are some L-T4-treated patients with normal TSH levels and persistent non-specific symptoms and discomforts.Therefore,combination therapy with L-T4and liothyronine (L-T3) has been considered as an alternative option for hypothyroidism.However,more prospective studies are needed to provide evidence-based effects for this kind of regimen.

Study on the prevalence of thyroid diseases during pregnancy in excess and sufficient water iodine area in Jiangsu Province / 中华内分泌代谢杂志

Objective To study the prevalence of thyroid disease in pregnant women living in both excess and sufficient water iodine area of in Jiangsu Province,and to establish an epidemiological database of thyroid disorders among pregnant women in different water iodine area in Jiangsu Province in order to guide our clinical practise.Methods Fengxian and Suining of Xuzhou were selected as excess and sufficient water iodine region.All the 439 pregnant women within the first trimester were enrolled in our study.The name,age,and previous history were recorded on questionnaire.The samples of fasting blood were obtained.Serum parameters such as free triiodothyronine ( FT3 ),free thyroxine ( FT4 ),total thyroxine ( TT4 ),thyrotropic stimulating hormone ( TSH ),and thyroid peroxidase (TPOAb) were measured by electrochemiluminescence assay.The data of the eligible 396 subjects were stored and analyzed by Epidata after excluding subjects with previous thyroid dysfuncion,renal disease,heart disease,and pregnancy-induced hypertension syndrome.Results Among the 396 subjects,197 women ( 49.7％ ) had thyroid disorders. The prevalence of hyperthyroidism, subclinical hyperthyroidism, hypothyroidism, subclinical hypothyroidism,hypothyroxinaemia,and thyroid autoimmunity were 0.5％,6.3％,3.3％,29.3％,9.3％,and 1.0％,respectively.The prevalence of subclinical hypothyroidism was significantly higher in excess water iodine region (32.4％) than that in sufficient water iodine area ( 19.6％ ),while the prevalence of other types of thyroid diseases such as subclinical hyperthyroidism,hyperthyroidism,hypothyroidism,hypothyroxinaemia,and TPOAbpositive cases in either excess or sufficient water iodine regions was not different.Conclusions Subclinical hyperthyridism,hypothyroxinaemia,and subclinical hypothyroidism are the main thyroid disorders in pregnant women in both excess and sufficient water iodine area.The prevalence of subclinical hypothyroidism increases obviously in excess water iodine region,indicating the relationship between thyroid disease and high iodine intake.

Clinical implications of thyrotropin receptor antibody measurement / 中华内分泌代谢杂志

It has been 50 years since the discovery of thyrotropin receptor autoantibody (TRAb). Advances in the knowledge of thyrotropin receptor ( TSHR) structure and function, combined with the elucidation of TSHR signaling and TSHR-autoantibody interaction have greatly facilitated our understanding of TRAb and their clinical applications. Measurement of TRAb activity plays an important role in the diagnosis of Graves' disease ( GD) and Graves' opthalmopathy. It has also been well recognized that TRAb is an effective predictor of GD relapse or remission after antithyroid drug and radioactive iodine treatment. TRAb test is of particular help in pregnant women and lactating mothers with recent iodine load, where radioactive iodine or technetium tests are contraindicated. In addition, it is useful in the diagnosis and differential diagnosis of fetal and neonatal hyperthyroidism as well as some rare forms of thyrotoxicosis in clinical practice. Accumulating evidence also indicates the possible correlation between thyroid cancer occurring in GD patients with positive TRAb and adverse outcomes. However, further innovation and standardization of TRAb tests are required to help pave the way for clinical applications.