ACTA ENDOCRINOLOGICA (BUC)

Objective. To observe the impact of quercetin and isoquercitrin on gluconeogenesis in hepatocytes. Methods. Mouse primary hepatocytes were cultured with lactic acid and pyruvic acid. After treatment with quercetin and isoquercitrin for 24 hours, the glucose concentration in the culture supernatant was determined. RT-PCR was used to detect the mRNAs of PEPCK, G6Pase, LKB1, and AMPKα. Protein levels of LKB1, AMPKα, and Thr172 phosphorylation were evaluated by Western blot. Results. The glucose concentration in the gluconeogenesis group (GN) was significantly higher than in the control group (C), but the glucose concentrations in the high level quercetin(group 80Q) and high level isoquercitrin (group 80I) were significantly lower than in the group GN, P<0.01. In the group 80Q, and group 80I, the mRNA levels of PEPCK and LKB1were significantly lower than in the group GN (P<0.01), and the G6Pase mRNA were significantly lower than in the group GN (P<0.05). The protein levels of LKB1 and the phosphorylation of AMPKα Thr172 in the group 80Q, group 40I, and group 80I were higher than in the group GN. The effects of quercetin and isoquercitrin on LKB1 and AMPKα were similar to those of metformin. Conclusions. Quercetin and isoquercitrin inhibit gluconeogenesis in hepatocytes, which may be related to the LKB1 upregulation and phosphorylation of AMPKα.

Objective. In this study we investigated the effect of dorsomedial hypothalamus (DMH) neuropeptide Y (NPY) knock-down on hepatic insulin sensitivity in high-fat (HF) diet-fed rats. Methods. Forty-eight Sprague-Dawley rats were randomly assigned to receive bilateral DMH injections of adeno-associated virus AAVshNPY or AAVshCTL and then accessed to regular chow. Five weeks after viral injection, half rats in each group were given access to the HF diet. At 16 weeks, rat livers were collected. Insulin receptor substrate-1 (IRS-1) and phosphoinositide 3-kinase (PI3K) mRNA expression was measured by qRT-PCR. Blood glucose levels were measured by the oxidase method, serum insulin, triglyceride, and TC levels were measured by Elisa. Pathological changes in the liver were assessed by hematoxylin-eosin (HE) staining. AKT, p-AKT, and GSK-3 levels were measured by western blotting. Results. Compared with AAVshCTL-injected rats, AAVshNPY-injected rats showed a significant decrease in blood glucose concentrations; serum insulin, triglyceride, and TC; HOMA-IR; and IRS-1 and PI3K mRNA levels (P<0.05). ISI, GSK-3, and p-AKT levels were significantly increased (P<0.05). HE staining showed that AAVshNPYinjected rats fed the HF diet had mild fatty degeneration. Conclusion. These results suggest that DMH NPY knock-down improves hepatic insulin sensitivity in HF diet-fed rats by activating the hepatic PI3K/AKT insulin signalling pathway.

Background. This study aimed to assess the mechanism through which Wnt/ beta - catenin signaling pathway, and StarD7, prometes testosterone synthesis, and to explore a new pathway for the regulation of testosterone synthesis. Animals and Methods. Leydig cells were isolated from male Sprague-Dawley rats divided into four groups and treated with Annexin 5 in concentration of 0, 0.1, 1 and 10 nmol/L. Testosterone secretion, expression of StarD7, StarD7 mRNA, β-catenin and changes of β – catenin localization in Leydig cells of testis of rats were tested in the four groups. Results. mRNA and protein levels of StarD7 and β-catenin increased significantly, upon stimulation with 1 nmol/L annexin 5. Accumulation of β-catenin inside the cells and the nucleus, was observed by immunofluorescence staining, in cells treated with annexin 5. These findings indicate a possible role of StarD7 and β-catenin in the process of annexin5-mediated stimulation of testosterone synthesis. Conclusions. Wnt/β-catenin signaling pathway and StarD7 are involved in the process of annexin5 stimulation of testosterone synthesis. Activation of Wnt/ β-catenin signaling pathway by Annexin5, and increase in StarD7 expression lead to elevated expression of key regulatory enzymes in testosterone synthesis, thus promoting testosterone synthesis.

The objective of this study is to investigate the relationship between paraoxonase 1 (PON1) activity and dyslipidaemia in Northern Chinese diabetic patients with chronic renal failure (DM-CRF). For this purpose, 45 diabetic patients with CRF, 63 non-diabetic patients with CRF, 90 type 2 diabetic patients without CRF were investigated, as well as 70 subjects without diabetes and CRF. The serum PON1 activity and serum lipids, high-density lipoprotein cholesterol (HDLc) were determined. The results showed that, as compared to control subjects, serum ArE1/PON1 activities were significantly decreased in patients with diabetes, CRF and DM-CRF. In a further investigation of the relationship among ArE/PON1 and lipid parameters in all groups, not only serum ArE/PON1 activity, but also ratios of serum ArE/TC and ArE/HDL3c were found to be significantly decreased in the three groups, and the degree of decrement was DM-CRF>CRF>diabetes. In DM-CRF group, multiple regression analysis showed that ArE/PON1 was closely related to HDL2C, Apo A1 and HDLC. ArE/TC was also related to HDL2C, Apo A1, HDLC/TC and HDLC. In conclusion, serum ArE/PON1 can be one of the signals reflecting the disorder of lipid metabolism of CRF, especially in DM-CRF patients.

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Objective. To study the correlation between neck circumference(NC) and umbilical artery blood flow in physiologic pregnancies. Methods. One hundred and one healthy pregnant woman in the third trimester were enrolled. Anthropometric measurements and ultrasonic testing were done. Results. The women with NC ≥34.7cm had a more elevated umbilical artery pulsatility index(PI) and systolic/diastolic ratio (S/D) than the women with NC <34.7cm (P<0.01). NC were positively correlated with PI(r=0.224,P=0.024) and S/D ratio(r=0.415,P=0.0001). In multivariate analysis, NC was independently associated with PI (β=0.026, P=0.016) and S/D ratio (β=0.132, P=0.0001). Conclusions. Obesity has an adverse impact on feto-placetal vessels, and NC was superior to body mass index.

Aim. To evaluate the diagnostic performance of radiomics features of two-dimensional (2D) and threedimensional (3D) ultrasound (US) in predicting extrathyroidal extension (ETE) status in papillary thyroid carcinoma (PTC). Patients and Methods. 2D and 3D thyroid ultrasound images of 72 PTC patients confirmed by pathology were retrospectively analyzed. The patients were assigned to ETE and non-ETE. The regions of interest (ROIs) were obtained manually. From these images, a larger number of radiomic features were automatically extracted. Lastly, the diagnostic abilities of the radiomics models and a radiologist were evaluated using receiver operating characteristic (ROC) analysis. We extracted 1693 texture features firstly. Results. The area under the ROC curve (AUC) of the radiologist was 0.65. For 2D US, the mean AUC of the three classifiers separately were: 0.744 for logistic regression (LR), 0.694 for multilayer perceptron (MLP), 0.733 for support vector machines (SVM). For 3D US they were 0.876 for LR, 0.825 for MLP, 0.867 for SVM. The diagnostic efficiency of the radiomics was better than radiologist. The LR model had favorable discriminate performance with higher area under the curve. Conclusion. Radiomics based on US image had the potential to preoperatively predict ETE. Radiomics based on 3D US images presented more advantages over radiomics based on 2D US images and radiologist.

Background. Saturated free fatty acids, such as palmitate, can cause pancreatic β-cell apoptosis. Although the toxicity of palmitate could be mediated partly through endoplasmic reticulum (ER) stress, the mechanism by which fatty acid over-accumulation led to lipoapoptosis in β-cells has not been fully understood. Recently, the fat mass and obesity associated (FTO) gene is proved to be related to obesity and type 2 diabetes, but its function in β-cells remains largely unknown. Whether or not FTO could counteract palmitate induced β-cell apoptosis remains to be investigated. Methods. INS-1 cells were infected with FTO expression adenovirus and incubated with palmitate. Then, viability and induction of apoptosis were measured by MTT assay and Hoechst-staining, respectively. Western blot analyses were performed for unfolded protein response specific proteins and mRNA expression of target molecules was determined by real time-PCR. Results. Palmitate incubation led to β-cell apoptosis, whereas adenovirus-mediated FTO overexpression significantly ameliorated the effect of palmitate. Increased activation of X-box binding protein 1 (Xbp1) mRNA and phosphorylation of eIF2α were also observed after palmitate treatment, whereas FTO overexpression significantly ameliorated the effect of palmitate. The proapoptotic transcription factor CHOP was significantly enhanced by palmitate incubation. In contrast, in accordance with sustained cell survival, FTO overexpression resulted in notably decreased CHOP levels. Interestingly, mRNA expression of the chaperones Pdi, Calnexin and Grp94 was not altered by palmitate treatment, while FTO overexpression notably increased the expression of Bip. Conclusion. Our data showed that FTO overexpression could protect β-cells from palmitate-induced apoptosis partly through suppression of ER stress.

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