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Open access

Ju-shuang Li, Tao Wang, Jing-jing Zuo, Cheng-nan Guo, Fang Peng, Shu-zhen Zhao, Hui-hui Li, Xiang-qing Hou, Yuan Lan, Ya-ping Wei, Chao Zheng, and Guang-yun Mao

Diabetic retinopathy (DR), the most common microvascular complication of diabetes and leading cause of visual impairment in adults worldwide, is suggested to be linked to abnormal lipid metabolism. The present study aims to comprehensively investigate the relationship between n-6 polyunsaturated fatty acids (PUFAs) and DR. This was a propensity score matching based case–control study, including 69 pairs of DR patients and type 2 diabetic patients without DR with mean age of 56.7 ± 9.2 years. Five n-6 PUFAs were determined by UPLC-ESI-MS/MS system. Principle component regression (PCR) and multiple conditional logistic regression models were used to investigate the association of DR risk with n-6 PUFAs depending on independent training and testing sets, respectively. According to locally weighted regression model, we observed obvious negative correlation between levels of five n-6 PUFAs (linoleic acid, γ-linolenic acid, eicosadienoic acid, dihomo-γ-linolenic acid and arachidonicacid) and DR. Based on multiple PCR model, we also observed significant negative association between the five n-6 PUFAs and DR with adjusted OR (95% CI) as 0.62 (0.43,0.87). When being evaluated depending on the testing set, the association was still existed, and PCR model had excellent classification performance, in which area under the curve (AUC) was 0.88 (95% CI: 0.78, 0.99). In addition, the model also had valid calibration with a non-significant Hosmer–Lemeshow Chi-square of 9.44 (P = 0.307) in the testing set. n-6 PUFAs were inversely associated with the presence of DR, and the principle component could be potential indicator in distinguishing DR from other T2D patients.

Open access

Malgorzata Oczko-Wojciechowska, Agnieszka Czarniecka, Tomasz Gawlik, Barbara Jarzab, and Jolanta Krajewska

Medullary thyroid cancer (MTC) is a rare thyroid malignancy, which arises from parafollicular C-cells. It occurs in the hereditary or sporadic form. Hereditary type is a consequence of activation of the RET proto-oncogene by germline mutations, whereas about 80% of sporadic MTC tumors harbor somatic, mainly RET or rarely RAS mutations. According to the current ATA guidelines, a postoperative MTC risk stratification and long-term follow-up are mainly based on histopathological data, including tumor stage, the presence of lymph node and/or distant metastases (TNM classification), and serum concentration of two biomarkers: calcitonin (Ctn) and carcinoembryonic antigen (CEA). The type of RET germline mutation also correlates with MTC clinical characteristics. The most common and the best known RET mutation in sporadic MTC, localized at codon 918, is related to a more aggressive MTC course and poorer survival. However, even if histopathological or clinical features allow to predict a long-term prognosis, they are not sufficient to select the patients showing aggressive MTC courses requiring immediate treatment or those, who are refractory to different therapeutic methods. Besides the RET gene mutations, there are currently no other reliable molecular prognostic markers. This review summarizes the present data of genomic investigation on molecular prognostic factors in medullary thyroid cancer.

Open access

Jing Zhang, Zhiyong Zhao, Li Dong, Tao Han, Guojin Zhang, Yuntai Cao, and Junlin Zhou

Introduction and aim

It is difficult to distinguish between non-functioning pituitary macroadenomas (NFPMAs) and sellar meningiomas because of their overlapping imaging manifestations on routine MRI, especially in cases of meningiomas growing into the saddle. Here, we aimed to differentiate between these two tumors using apparent diffusion coefficient (ADC) values and MRI characteristics.

Methods

A total of 60 NFPMA and 52 sellar meningioma cases confirmed by the pathological analysis were retrospectively reviewed. All patients were examined via routine MRI and diffusion-weighted imaging (DWI) before undergoing surgery. The clinical characteristics, MRI characteristics, and max ADC (ADCmax), average ADC (ADCmean), and minimum ADC (ADCmin) values were compared between the two tumors via Chi-square test and two sample t-tests. Receiver operating characteristic (ROC) curve and binary logistic regression analyses were conducted to determine the discrimination ability.

Results

The ADCmax, ADCmean, and ADCmin values were significantly higher in NFPMAs compared to sellar meningiomas (P < 0.001 for all). Among ADC values, ADCmax demonstrated good performance with an AUC of 0.896 (95% CI, 0.823–0.969) and accuracy of 88.7%. A cut-off value of 0.97 × 10−3 mm2/s was used for ADCmax for differentiation between tumors. A combination of ADCmax values and clinicoradiological features showed the best discrimination ability for differential diagnosis between the two tumors, with an AUC of 0.981 (95% CI, 0.958–1.000) and accuracy of 96.9%.

Conclusion

A combination of ADCmax and clinicoradiological features demonstrates good discrimination ability and high accuracy for differentiation between NFPMAs and sellar meningiomas, and is a potential quantitative tool to aid in the selection of surgical techniques.

Open access

Jasmin Asberger, Thalia Erbes, Markus Jaeger, Gerta Rücker, Claudia Nöthling, Andrea Ritter, Kai Berner, Ingolf Juhasz-Böss, and Marc Hirschfeld

Breast cancer (BC) represents the most common type of cancer in females worldwide. Endocrine therapy evolved as one of the main concepts in treatment of hormone-receptor positive BC. Current research focuses on the elucidation of tumour resistance mechanisms against endocrine therapy. In a translational in vitro approach, potential regulatory effects of clinically implemented BC anti-oestrogens on ERα, its coactivators DDX5, DDX17 and other DEADbox proteins as well as on the proliferation markers cyclin D1 and Ki67 were investigated on both the RNA and protein level. BC in vitro models for hormone-receptor positive (MCF-7, T-47D) and hormone-receptor negative cells (BT-20) were subjected to endocrine therapy. Anti-oestrogen-dependent expression regulation of target genes on the transcriptional and translational level was quantified and statistically assessed. Endocrine therapy decreases the expression levels of Ki67, cyclin D1 and ERα in hormone-receptor positive cells. In the hormone-receptor negative cells, the three parameters remained stable after endocrine therapy. Endoxifen triggers a downregulation of DDX5 and DDX23 in MCF-7 cells. Fulvestrant treatment downregulates the expression levels of all investigated DEADbox proteins in MCF-7 cells. In T-47D cells, endoxifen and fulvestrant lead to a decrease of all target gene expression levels. Interestingly, endocrine therapy affects DEADbox RNA expression levels in BT-20 cells, too. However, this result could only be confirmed for DDX1, immunocytologically. The investigated DEADbox proteins appear to correlate with the oestrogen-dependent tumourigenesis in hormone-receptor positive BC and show expression alterations after endocrine treatment.

Open access

Emanuelle Nunes-Souza, Mônica Evelise Silveira, Monalisa Castilho Mendes, Seigo Nagashima, Caroline Busatta Vaz de Paula, Guilherme Guilherme Vieira Cavalcante da Silva, Giovanna Silva Barbosa, Julia Belgrowicz Martins, Lúcia de Noronha, Luana Lenzi, José Renato Sales Barbosa, Rayssa Danilow Fachin Donin, Juliana Ferreira de Moura, Gislaine Custódio, Cleber Machado-Souza, Enzo Lalli, and Bonald Cavalcante de Figueiredo

Objective

Adaptive changes in DHEA and sulfated-DHEA (DHEAS) production from adrenal zona reticularis (ZR) have been observed in normal and pathological conditions. Here we used three different cohorts to assess timing differences in DHEAS blood level changes and characterize the relationship between early blood DHEAS reduction and cell number changes in women ZR.

Materials and methods

DHEAS plasma samples (n = 463) were analyzed in 166 healthy prepubertal girls before pubarche (<9 years) and 324 serum samples from 268 adult females (31.9–83.8 years) without conditions affecting steroidogenesis. Guided by DHEAS blood levels reduction rate, we selected the age range for ZR cell counting using DHEA/DHEAS and phosphatase and tensin homolog (PTEN), tumor suppressor and cell stress marker, immunostaining, and hematoxylin stained nuclei of 14 post-mortem adrenal glands.

Results

We confirmed that overweight girls exhibited higher and earlier DHEAS levels and no difference was found compared with the average European and South American girls with a similar body mass index (BMI). Adrenopause onset threshold (AOT) defined as DHEAS blood levels <2040 nmol/L was identified in >35% of the females >40 years old and associated with significantly reduced ZR cell number (based on PTEN and hematoxylin signals). ZR cell loss may in part account for lower DHEA/DHEAS expression, but most cells remain alive with lower DHEA/DHEAS biosynthesis.

Conclusion

The timely relation between significant reduction of blood DHEAS levels and decreased ZR cell number at the beginning of the 40s suggests that adrenopause is an additional burden for a significant number of middle-aged women, and may become an emergent problem associated with further sex steroids reduction during the menopausal transition.

Open access

Caishun Zhang, Junhua Yuan, Qian Lin, Manwen Li, Liuxin Wang, Rui Wang, Xi Chen, Zhengyao Jiang, Kun Zhu, Xiaoli Chang, Bin Wang, and Jing Dong

Ghrelin plays a pivotal role in the regulation of food intake, body weight and energy metabolism. However, these effects of ghrelin in the lateral parabrachial nucleus (LPBN) are unexplored. C57BL/6J mice and GHSR−/− mice were implanted with cannula above the right LPBN and ghrelin was microinjected via the cannula to investigate effect of ghrelin in the LPBN. In vivo electrophysiological technique was used to record LPBN glucose-sensitive neurons to explore potential udnderlying mechanisms. Microinjection of ghrelin in LPBN significantly increased food intake in the first 3 h, while such effect was blocked by [D-Lys3]-GHRP-6 and abolished in GHSR−/− mice. LPBN ghrelin microinjection also significantly increased the firing rate of glucose-excited (GE) neurons and decreased the firing rate of glucose-inhibited (GI) neurons. Additionally, LPBN ghrelin microinjection also significantly increased c-fos expression. Chronic ghrelin administration in the LPBN resulted in significantly increased body weight gain. Meanwhile, no significant changes were observed in both mRNA and protein expression levels of UCP-1 in BAT. These results demonstrated that microinjection of ghrelin in LPBN could increase food intake through the interaction with growth hormone secretagogue receptor (GHSR) in C57BL/6J mice, and its chronic administration could also increase body weight gain. These effects might be associated with altered firing rate in the GE and GI neurons.

Open access

Qinglei Yin, Zhou Jin, Yulin Zhou, Dalong Song, Chenyang Fu, FengJiao Huang, and Shu Wang

Graves’ disease (GD) is a common autoimmune disease that affects the thyroid gland. As a new class of modulators of gene expression, long noncoding RNAs (lncRNAs) have been reported to play a vital role in immune functions and in the development of autoimmunity and autoimmune disease. The aim of this study is to identify lncRNAs in CD4+ T cells as potential biomarkers of GD. lncRNA and mRNA microarrays were performed to identify differentially expressed lncRNAs and mRNAs in GD CD4+ T cells compared with healthy control CD4+ T cells. Quantitative PCR (qPCR) was used to validate the results, and correlation analysis was used to analyze the relationship between these aberrantly expressed lncRNAs and clinical parameters. The microarray identified 164 lncRNAs and 93 mRNAs in GD CD4+ T cells differentially expressed compared to healthy control CD4+ T cells (fold change >2.0 and a P < 0.05). Further analysis consistently showed that the expression of HMlincRNA1474 (P < 0.01) and TCONS_00012608 (P < 0.01) was suppressed, while the expression of AK021954 (P < 0.01) and AB075506 (P < 0.01) was upregulated from initial GD patients. In addition, their expression levels were recovered in euthyroid GD patients and GD patients in remission. Moreover, these four aberrantly expressed lncRNAs were correlated with GD clinical parameters. Moreover, the areas under the ROC curve were 0.8046, 0.7579, 0.8115 for AK021954, AB075506, HMlincRNA1474, respectively. The present work revealed that differentially expressed lncRNAs were associated with GD, which might serve as novel biomarkers of GD and potential targets for GD treatment.

Open access

David S Mathiesen, Jonatan I Bagger, Katrine B Hansen, Anders E Junker, Astrid Plamboeck, Signe Harring, Thomas Idorn, Mads Hornum, Jens J Holst, Anna E Jonsson, Torben Hansen, Tina Vilsbøll, Asger Lund, and Filip K Knop

The T allele of TCF7L2 rs7903146 is a common genetic variant associated with type 2 diabetes (T2D), possibly by modulation of incretin action. In this study, we evaluated the effect of the TCF7L2 rs7903146 T allele on the incretin effect and other glucometabolic parameters in normal glucose tolerant individuals (NGT) and participants with T2D. The rs7903146 variant was genotyped in cohorts of 61 NGT individuals (23 were heterozygous (CT) or homozygous (TT) T allele carriers) and 43 participants with T2D (20 with CT/TT). Participants were previously examined by an oral glucose tolerance test (OGTT) and a subsequent isoglycemic intravenous glucose infusion (IIGI). The incretin effect was assessed by quantification of the difference in integrated beta cell secretory responses during the OGTT and IIGI. Glucose and hormonal levels were measured during experimental days, and from these, indices of beta cell function and insulin sensitivity were calculated. No genotype-specific differences in the incretin effect were observed in the NGT group (P = 0.70) or the T2D group (P = 0.68). NGT T allele carriers displayed diminished glucose-dependent insulinotropic polypeptide response during OGTT (P = 0.01) while T allele carriers with T2D were characterized by lower C-peptide AUC after OGTT (P = 0.04) and elevated glucose AUC after OGTT (P = 0.04). In conclusion, our findings do not exclude that this specific TCF7L2 variant increases the risk of developing T2D via diminished incretin effect, but genotype-related defects were not detectable in these cohorts.

Open access

Jeyanthini Risikesan, Birgitte Nellemann, Britt Christensen, Jens Otto Lunde Jørgensen, and Søren Nielsen

Studies indicate that erythropoietin (EPO) has effect on lipid and energy metabolism; however, the impact of EPO on lipid oxidation in vivo has not been well documented. Here, we evaluate whether long-term erythropoiesis-stimulating agent (ESA) treatment affects the oxidation of plasma very low-density lipoprotein triglycerides (VLDL-TG) fatty acids (FA), plasma free fatty acids (FFA) and non-plasma (residual) FA in healthy, young, sedentary men. Infusion of [1-14C]VLDL-TG and [9,10-3H]palmitate was used in combination with indirect calorimetry to assess resting lipid fuel utilization and kinetics, and resting energy expenditure (REE) before and after 10 weeks of ESA exposure compared with placebo. REE increased significantly during ESA compared with placebo (P = 0.023, RM-ANOVA). Oxidation rates of VLDL-TG FA, FFA, and residual FA remained unchanged during ESA compared with placebo. The relative contribution of the lipid stores was greatest for FFA (47.1%) and the total lipid oxidation rate and was not significantly different between ESA and placebo-treated subjects. We conclude that long-term ESA treatment of healthy young men increases REE but does not alter the oxidation rates of plasma and non-plasma FA sources.

Open access

Bernardo Maia, Leandro Kasuki, and Mônica R Gadelha

Acromegaly is a systemic disease associated with increased morbidity and mortality. Most of these comorbidities can be prevented or delayed with adequate disease treatment. Although three modalities of treatment (surgery, medical treatment, and radiotherapy) are available and new drugs were approved in the last decades, there are still some patients that maintain disease activity despite treatment. Therefore, there is a need for novel therapies for acromegaly and for that purpose new formulations of currently used drugs and also new drugs are currently under study. In this review, we summarize the novel therapies for acromegaly.