The role of interleukin-1ß and extracellular signal-regulated kinase 1/2 in glucose-stimulated insulin secretion.

Glucose-stimulated insulin secretion (GSIS) is one of the important physiological characteristics of islet ß cells, and extracellular-regulated protein kinase 1/2 (ERK1/2) is an important member of the mitogen-activated protein kinase family that regulates this process. The inflammatory cytokine interleukin (IL)-1ß can inhibit the insulin secretion of pancreatic ß cells, but the exact mechanism is unclear. This study was designed to investigate the inhibitory effect of IL-1ß on GSIS in ßTC-6 cells and its relation with the ERK1/2 signal transduction pathway. ß-TC6 cells were cultured and stimulated with 0mM, 1.38mM, or 5.5mM glucose. In addition, GSIS in ß-TC6 cells was blocked by IL-1ß at concentrations of 0.15 ng/mL, 1.5 ng/mL, and 15 ng/mL. After glucose stimulation and IL-1ß intervention, the insulin level in the cell supernatant was detected by radioimmunoassay, and the phosphorylation level of ERK1/2 was detected by western blotting assay. The insulin level in the 1.38mM glucose group was 108.52 ± 5.94 uIU/mL, which was significantly higher than the 0mM and 5.5mM glucose groups (p < 0.05). Compared with the 0mM glucose group, the level of ERK1/2 phosphorylation was increased in the 1.38mM and 5.5mM glucose groups. After intervention by 0.15 ng/mL, 1.5 ng/mL, and 15 ng/mL IL-1ß, the level of ERK1/2 phosphorylation induced by 1.38mM glucose stimulation decreased in a dose-dependent manner, and the insulin level correspondingly decreased. IL-1ß can inhibit GSIS in ßTC-6 cells, which is related to its inhibition of the phosphorylation of ERK1/2.

Papillary thyroid carcinoma risk factors in the Yunnan plateau of southwestern China.

OBJECTIVE: This study investigated clinical and pathological characteristics and risk factors in papillary thyroid carcinoma (PTC) patients' native to Yunnan plateau in southwestern China. METHODS: Clinical data from 1,198 patients diagnosed with PTC (n=578) and control subjects (n=620) with benign thyroid disease (ie, thyroid nodule disease, benign thyroid diseases [BTD]) in Yunnan province were analyzed retrospectively. RESULTS: The mean patient age was lower for PTC than for BTD. Positive ratios of thyroid peroxidase antibody, thyroglobulin antibody (TGAb), and thyrotrophin receptor antibody (TRAb) were higher in PTC than in BTD patients. The ratio of PTC coexisting with Hashimoto's thyroiditis (HT) or with lymphocytic thyroiditis was higher than that of BTD. The number of patients whose age at menarche was ≤13 years, who had given birth to less than or equal to two children, or who were in premenopause were higher in the PTC than in the BTD group. Multivariate conditional logistic regression analyses revealed that age >45 years, nodal size >1 cm, and elevated TG levels were protective factors against PTC. Abnormally elevated TGAb and TRAb levels were independent risk factors for PTC in females. CONCLUSION: HT was not an independent risk factor for but was associated with PTC. TRAb is a risk factor for PTC in individuals living in the Yunnan plateau, but not for those in the plains region.