GLP-1 receptor agonist liraglutide inhibits the proliferation and migration of thyroid cancer cells.

This research was done to find out how liraglutide affected the growth and movement of two human thyroid cancer cell lines overexpressing GLP-1 receptor (migration of medullary thyroid cancer TT/GLP-1R and papillary thyroid carcinoma TCP-1/GLP-1R). Flow cytometer and cAMP assays were used to identify the expression and activation of GLP-1R in two stable cell lines. Counting Kit-8 for Cells was applied to examine the proliferative ability of cells in two stable cell lines after treatment with different concentrations of liraglutide at indicated time points. To track the capacity for cell migration, the Transwell test was utilized. We found that liralutide-activated GLP-1R could significantly reduce the growth and metastasis of two kinds of thyroid tumor cells, and the inhibitory effect was dose- and time- dependent. The phosphorylatios of Akt, S6K1, and 70SK declined after receiving liraglutide therapy In our previous studies, we found that the GLP-1 receptor agonist Liraglutide inhibited the proliferation and migration of thyroid cancer cells through the PI3K/Akt/mTOR pathway. This finding provides a theoretical basis for the treatment of diabetes mellitus complicated with medullary thyroid cancer, and is relatively safe.

FOXO3a regulates lipid accumulation and adipocyte inflammation in adipocytes through autophagy : Role of FOXO3a in obesity.

BACKGROUND: FOXO3a is a widely studied transcription factor and plays an important role in a variety of biology. The purpose of this study was to explore the role and potential mechanism of FOXO3a on lipid accumulation and adipocyte inflammation in adipocytes through regulation of autophagy. METHODS: The obese mouse model was successfully induced by high-fat diet. SiRNA targeting FOXO3a was transfected into differentiation of 3T3-L1 adipocytes to reduce the expression of FOXO3a. The culture medium of RAW264.7 cells was added to the differentiated 3T3-L1 adipocytes to form a co-culture system. Subsequently, ELISA or AdipoRed assay was performed to measure the expression of triglyceride (TG) and cholesterol (TC) in mouse adipose tissue or differentiation of 3T3-L1 adipocytes. Adipocyte differentiation was detected by Oil Red O-staining. Ad-mCherry-GFP-LC3II was used to detect the level of autophagy in differentiation of 3T3-L1 adipocytes. Western blotting or qRT-PCR was used to detect the expression of FOXO3a, autophagy-related proteins (beclin 1, CEBPß, PPARγ, ACC1 and KLF4), inflammatory cytokines (TNF-α, IL-1ß, IL-6 and MCP1), NF-κB signal pathway-related proteins or adipokines (Adiponectin, AdipoR1 and resistin) in differentiated 3T3-L1 or RAW264.7 cells. RESULTS: The expression of FOXO3a and autophagy levels were significantly increased in visceral adipose tissue of obese mice and differentiation of 3T3-L1 adipocytes. Downregulation of FOXO3a significantly inhibited the autophagy and lipid accumulation in differentiation of 3T3-L1 adipocytes. In addition, FOXO3a knockdown significantly reduced Lipopolysaccharide (LPS)-induced inflammation and adipokines release in RAW264.7 cells treated with the culture medium of 3T3-L1 adipocytes. These above activity changes could be reversed by autophagy inducer rapamycin. CONCLUSION: FOXO3a could promote lipid accumulation and inflammation in differentiated 3T3-L1 adipocytes by targeting autophagy. Our results provide a new theoretical basis for FOXO3a to regulate obesity.

Gender difference in the relationship between serum uric acid reduction and improvement in body fat distribution after laparoscopic sleeve gastrectomy in Chinese obese patients: a 6-month follow-up.

BACKGROUND: Hyperuricemia is related to obesity and fat accumulation. This study aimed to observe the effects of laparoscopic sleeve gastrectomy (LSG) on serum uric acid (sUA) level and body fat distribution in obese patients. The relationships between post-LSG improvement in sUA levels and body fat distribution changes, as well as their sex-related differences, were also explored. METHODS: In total, 128 obese patients (48 men; 80 women) who underwent LSG were enrolled. Anthropometric indicators, glucose and lipid metabolic indicators, and sUA levels were measured pre-LSG and 6 months post-LSG. The body compositions were measured via dual-energy X-ray absorptiometry. The patients were divided into normal-sUA (NUA) and high-sUA (HUA) groups based on preoperative sUA levels. RESULTS: Compared with the NUA group, the reduction of sUA levels 6 months post-LSG was more significant in the HUA group. In addition, sUA reduction in the female HUA group was more significant than that of the male HUA group (P < 0.01). Changes in serum uric acid levels (ΔsUA) in the male HUA group was positively correlated with changes in body weight, body mass index, neck circumference, and hip circumference (r = 0.618, 0.653, 0.716, and 0.501, respectively; P < 0.05 in all cases). It was also positively correlated with changes in fat mass in the gynoid region, android region, and legs, (r = 0.675, 0.551, and 0.712, respectively; P < 0.05 in all cases), and negatively correlated with changes in total testosterone (ΔTT) (r = - 0.517; P = 0.040). Furthermore, ΔTT in this group was closely associated with the improved sex-related fat distribution. The ΔsUA in the female HUA group was positively correlated with changes in fasting serum C peptide and ΔLNIR (r = 0.449 and 0.449, respectively; P < 0.05 in both cases). In addition, it was also positively correlated with changes in visceral adipose tissue (VAT) fat mass, VAT fat volume, and VAT fat area (r = 0.749, 0.749, and 0.747, respectively; P < 0.01 in all cases). CONCLUSIONS: sUA levels of obese patients with hyperuricemia improved 6 months after LSG. Reduction of sUA after LSG was correlated with improved body fat distribution, and the relationships also displayed sex-based differences. Uric acid might be an important metabolic regulator associated with fat distribution and sex hormones.

The Effect of Diacerein on Type 2 Diabetic Mellitus: A Systematic Review and Meta-Analysis of Randomized Controlled Trials with Trial Sequential Analysis.

AIMS: To figure out the effect of diacerein supplementation on type 2 diabetes mellitus (T2DM). METHODS: An electronic search was processed on Pubmed, Embase, and Cochrane library for randomized controlled trials (RCTs) comparing the efficacy of diacerein with placebo on T2DM. The primary outcome was fasting blood glucose (FBG). Trial sequential analysis (TSA) was used to test the reliability of this pooled outcome. Secondary outcomes were glycosylated hemoglobin A1c (HbA1c), body mass index (BMI), lipid profiles, hematological indexes including hematocrit and platelet count, and systematic inflammatory level expressed as a C-reactive protein (CRP) level. Safety outcome was the rate of complications. The difference in continuous data was measured by mean difference (MD) and 95% confidence interval (CI), while the difference of dichotomous data was calculated by relative risk (RR) and 95% CI. A two-tailed P < 0.05 was regarded as statistically significant. RESULTS: Five RCTs with 278 participants were included. Compared with control, diacerein provided significant improvement on FBG (MD -0.52; 95% CI (-0.89~-0.14); P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. P < 0.05 was regarded as statistically significant. CONCLUSION: Based on the current analysis, diacerein as an add-on treatment provided better glycemic control for T2DM but this benefit requires more verification. Compared with control, additional diacerein also lowered body weight and CRP level in T2DM, but increased the rate of gastrointestinal syndromes.

[The effect and pathophysiological mechanism of high free fatty acids(FfAs) on the cardiac structure and function].

OBJECTIVE: To study the pathophysiological links between elevated circulating FFAs concentration and the cardiac structure, and their function in obese insulin resistance rat model. METHODS: 4 weeks age male SD rats were fed with high-fat chow (OB) or standard laboratory chow (NC) respectively. Whole-body insulin sensitivity, the maximum velocity of myocardial contraction (+dp/dt(max)) and the maximum velocity of myocardial diastole (-dp/dt(max)) of intracardiac pressure, and myocardiac cell diameter (MCD) were measured. The concentrations of triglyceride (TG), FFAs and angiotensin II (Ang II) both in blood and in left ventricular portions of heart and the expressions of NF-kappaB, I-kappaB and iNOS in myocardium were analyzed. RESULTS: OB group developed obesity and left ventricular hypertrophy, and their insulin sensitivity was much lower than that of control group. Obese rats had higher plasma concentrations of TG, FFAs and Ang II. Accordingly, dramatic lipid deposition occurred within cardiomyocytes of obese rats, and the value of myocardiac Ang II was also increased. High-fat diet also induced a progressive decrease in values of +dp/dt(max) and -dp/dt(max). The higher expressions of NF-kappaB and iNOS in myocardium were observed in OB group, while IkappaB lower. Intramyocardial lipid deposition was associated with plasma FFAs concentrations (r = 0.80, P < 0.01). Intramyocardial FFAs concentration was associated with myocardial Ang II concentration (r = 0.74, P < 0.05) and changes in expressions of NF-kappaB (r = 0.86, P < 0.01), iNOS (r = 0.66, P < 0.05). The contractile dysfunction was associated with intramyocardial lipid deposition (r = -0.87, P < 0.01), Ang II (r = -0.52, P < 0.05) and expressions of NF-kappaB (r = -0.57, P < 0. 01), iNOS (r = -0.70, P < 0. 01). The diastolic dysfunction was associated with intramyocardial lipid deposition ( r = -0.85, P < 0.01), Ang II (r = -0.82, P<0.01) and expressions of NF-kappaB (r = -0.75, P < 0.01), iNOS (r = -0.78, P < 0.01). CONCLUSION: In obese/insulin resistance, state ectopic lipid accumulation in myocardium as the results of elevated circulating FFAs and TG concentration impairs cardiac systolic and diastolic functions. It is logical to deduce that ectopic lipid accumulation in myocardium may increase RAS activity and expressions of NF-kappaB, iNOS in myocardium, all of them have important roles to increase the risk of congestive heart failure in obese subjects.

Contribution of birth weight and adult waist circumference to cardiovascular disease risk in a longitudinal study.

To determine the association of birth weight (BW) and waist circumference (WC) on cardiovascular disease (CVD). The longitudinal cohort study consisted of 745 participants who were able to provide their birth weight information and were followed from 2002 to 2014. During the follow-up, 83 events of CVD were confirmed. After adjusting for confounding factors, subjects with birth weight <2500 g were at a significantly increased CVD risk when compared to subjects with birth weight between 2500-3999 g (OR 2·47, 95%CI, 1·07-5·71). When high waist circumference (HWC), a measurement of adult obesity, was incorporated into stratifying factors according to presence or absence of low birth weight (LBW, birth weight <2500 g), adjusted CVD risk was significantly elevated in -LBW/+ HWC group (OR 1·94, 95%CI, 1·10-3·43) and marginally significantly increased in +LBW/-HWC group (OR 2·94, 95%CI, 1·00-8·64). CVD risk was highest in subjects with LBW and HWC (+LBW/+HWC), OR 4·74 (95%CI, 1·48-15·21). Higher waist circumference in adulthood is an especially strong risk factor for cardiovascular disease among those small at birth. In this cohort, birth size and adiposity in adulthood interact to predict events of cardiovascular disease.

Gender-related affecting factors of prediabetes on its 10-year outcome.

OBJECTIVE: To investigate the gender-related affecting factors of prediabetes on its 10-year outcome, in a longitudinal study. METHODS AND RESULTS: This longitudinal population-based study was performed in the Ping Liang community, Yangpu district, Shanghai, between November 2002 and October 2014. There were 334 participants with prediabetes enrolled in the final analysis. While a certain proportion of the prediabetic population progress to diabetes, the majority remain at the same level or even revert to normal glucose regulation. No gender difference was observed in the change of glucose regulation. However, results from an adjusted logistic regression analysis in males showed that physical activity was significantly associated with both elevated odds of reverting to normal glucose regulation (active vs inactive, OR 3.00, 95% CI 1.09 to 8.30) and developing diabetes (OR 0.34, 95% CI 0.13 to 0.92). Age, baseline 2 h glucose, triglycerides and smoking status were also risk factors significantly associated with diabetes development; while for females, waist circumference played a key role in the outcome. Every unit elevation of waist circumference was associated with lower odds of reverting to normal glucose regulation (OR, 0.94; 95% CI 0.89 to 0.98) and higher odds of progressing to diabetes (OR, 1.05; 95% CI 1.01 to 1.10). Baseline hypertension and family history of diabetes carried higher risk for developing diabetes as well. CONCLUSIONS: Physical activity in males and waist circumference in females are important factors predicting both progression to diabetes and regression to normal glucose regulation, indicating that more exercise for males and lower waist circumference for females are beneficial for prediabetes to achieve reversion.

Roles of SHARP1 in thyroid cancer.

SHARP1 is a basic helix­loop­helix transcription factor involved in various cellular processes, including proliferation and differentiation. The present study assessed the role of SHARP1 in the progression and invasion of thyroid cancer. PCR and western blot analysis demonstrated that in thyroid cancer tissues, SHARP1 was significantly downregulated at the mRNA and protein level compared with that in normal tissues. Furthermore, SHARP1 was downregulated in the TT and TPC­1 thyroid cancer cell lines compared with a normal thyroid cell line, while it was upregulated in other thyroid cancer cell lines. Overexpression of SHARP1 in TT and TPC­1 cells significantly inhibited the cell viability, migration and invasion in vitro. Furthermore, the protein and mRNA levels of HIF­1α were found to be decreased in TT and TPC­1 cells following forced overexpression of SHARP1. In addition, silencing of HIF­1α reduced the viability, migration and invasion of TT and TPC-1 cells. In conclusion, the present study indicated that SHARP1 acts as a tumor suppressor in thyroid cancer and that its downregulation may contribute to the proliferation, migration and invasion of thyroid cancer cells through mechanisms possibly involving HIF­1α, suggesting that SHARP1 may be an important therapeutic target for the treatment of thyroid cancer.

[A study on the mechanism of islet cell insulin resistance in high-fat-diet obese rats].

OBJECTIVE: To study the changes of insulin signal transduction in islet cells of high-fat-diet rats with peripheral insulin resistance (IR). METHODS: Thirty male Wistar rats were randomly divided into 2 equal groups: high-fat-diet group and control group to be fed with high-fat food and normal food respectively. Twenty weeks after the rats were sacrificed. The contents of insulin and glucagon in homogenate of pancreas were detected during islet cell perifusion, and insulin receptor (IRc) and insulin receptor substrates (IRS-1 and IRS-2) were detected by immunohistochemistry. RESULTS: (1) The insulin sensitive index (ISI) was significantly decreased in the high-fat-diet rats in comparison with the normal rats, while the contents of glucagon in blood and in homogenate of pancreas were both significantly increased in the high-fat-diet rats (362 pg/ml +/- 58 pg/ml vs 291 pg/ml +/- 35 pg/ml; 442 pg/ml +/- 56 pg/ml vs 287 pg/ml +/- 48 pg/ml, both P < 0.05). (2) The glucose stimulated insulin secretion (GSIS) was impaired in the high-fat-diet rats. 16.7 nmol/L glucose could inhibit the glucagon secretion by the alpha cells of the normal rats, but not of the high-fat-diet rats. (3) The expression of IRc, IRS-1 and IRS-2 in islets was stronger in the peripheral cells (non-insulin secretion cells) than in the center cells (insulin secretion cells). The expression of IRc and IRS-2 was significantly decreased by 28% and 22% respectively in the high-fat-diet rats compared with the normal controls (both P < 0.01). CONCLUSION: High-fat-diet rats have impairment of insulin signal transduction in islet cells, which may contribute to the insulin resistance of islet alpha and beta cells and explain, at least in part, the dysfunction of the islet cells under peripheral IR.