Melanocortin receptors (MCRs) and their accessory proteins (MRAPs) evolutionarily first appear in the genome of sea lamprey. The most ancient melanocortin system consists of only two melanocortin receptors (slMCa and slMCb) and one MRAP2 (slMRAP2) protein, but the physiological roles have not been fully explored in this primitive species. Here, we synthesize and characterize the pharmacological features of slMRAP2 protein on two slMCRs. Our results show that the slMRAP2 protein lacks the long carboxyl terminus; it directly interacts and decreases the surface expression but enhances the α-MSH-induced agonism of slMCa and slMCb. In comparison with higher organisms such as elephant shark and zebrafish, we also demonstrate the constantly evolving regulatory function of the carboxyl terminus of MRAP2 protein, the unique antiparallel topology of slMRAP2 dimer and the homo- and hetero-dimerization of two slMCRs. This study elucidates the presence and modulation of melanocortin receptor by the accessory protein of the agnathans for the first time, which provides a better insight of the melanocortin system in ancient species of chordates.
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Ming Zhu, Bingxin Xu, Meng Wang, Shangyun Liu, Yue Zhang and Chao Zhang
Jia Li, Yan Zhao, Caoxin Huang, Zheng Chen, Xiulin Shi, Long Li, Zhong Chen and Xuejun Li
Exercise benefits people with nonalcoholic fatty liver disease (NAFLD). The aim of this study was to identify a panel of biomarkers and to provide the possible mechanism for the effect of exercise on NAFLD patients via an untargeted mass spectrometry-based serum metabolomics study.
NAFLD patients were classified randomly into a control group (n = 74) and a 6-month vigorous exercise (n = 68) group. Differences in serum metabolic profiles were analyzed using untargeted ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) technology. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to validate the differences between these two groups, and altered metabolites were obtained by ANOVA (fold change >2, P < 0.05) and identified with the online database Metlin and an in-house database.
Metabolic profiling and multiple statistical analyses of the serum samples indicated significant differences between the NAFLD patients in the control and the 6-month vigorous exercise groups. Finally, 36 metabolites were identified between the control vs exercise groups. These metabolites were mainly associated with glycerophospholipid- and sphingolipid-related pathways.
Our study demonstrates that glycerophospholipid and sphingolipid alterations may contribute to the mechanism underlying the effect of exercise on NAFLD patients. A LC-MS-based metabolomics approach has a potential value for screening exercise-induced biomarkers.
Ananda A Santana-Ribeiro, Giulliani A Moreira-Brasileiro, Manuel H Aguiar-Oliveira, Roberto Salvatori, Vitor O Carvalho, Claudia K Alvim-Pereira, Carlos R Araújo-Daniel, Júlia G Reis-Costa, Alana L Andrade-Guimarães, Alécia A Oliveira-Santos, Edgar R Vieira and Miburge B Gois-Junior
Walking and postural balance are extremely important to obtain food and to work. Both are critical for quality of life and ability to survive. While walking reflects musculoskeletal and cardiopulmonary systems, postural balance depends on body size, muscle tone, visual, vestibular and nervous systems. Since GH and IGF-I act on all these systems, we decided to study those parameters in a cohort of individuals with severe short stature due to untreated isolated GH deficiency (IGHD) caused by a mutation in the GHRH receptor gene. These IGHD subjects, despite reduction in muscle mass, are very active and have normal longevity.
In a cross-sectional study, we assessed walking (by a 6-min walk test), postural balance (by force platform) and fall risk (by the 'Timed Up and Go' test) in 31 IGHD and 40 matched health controls.
The percentage of the walked distance measured in relation to the predicted one was similar in groups, but higher in IGHD, when corrected by the leg length. Absolute postural balance data showed similar velocity of unipodal support in the two groups, and better values, with open and closed eyes and unipodal support, in IGHD, but these differences became non-significant when corrected for height and lower-limb length. The time in 'Timed Up and Go' test was higher in IGHD cohort, but still below the cut-off value for fall risk.
IGHD subjects exhibit satisfactory walking and postural balance, without increase in fall risk.
Weixi Wang, Rulai Han, Lei Ye, Jing Xie, Bei Tao, Fukang Sun, Ran Zhuo, Xi Chen, Xiaxing Deng, Cong Ye, Hongyan Zhao and Shu Wang
Up to 40% of multiple endocrine neoplasia type 1 (MEN1) patients may have adrenal cortical tumors. However, adrenocortical carcinoma (ACC) is rare. The clinical manifestations, prevalence, inheritance and prognosis of ACC associated with MEN1 remain unclear. Here we report the clinical manifestations and prevalence of ACC in patients with MEN1.
Design and methods
A retrospective analysis of ACC associated with MEN1 patients at a single tertiary care center from December 2001 to June 2017. Genetic analysis of MEN1 and other ACC associated genes, loss of heterozygosity (LOH) of MEN1 locus, immunohistochemistry staining of menin, P53 and β-catenin in ACC tissue were performed.
Two related patients had ACC associated with MEN1. The father had ENSAT stage IV tumor with excessive production of cortisol; the daughter had nonfunctional ENSAT stage I tumor. Both patients carried novel germline heterozygous mutation (c.400_401insC) of MEN1. The wild-type MEN1 allele was lost in the resected ACC tissue from the daughter with no menin staining. The ACC tissue had nuclear β-catenin staining, with heterozygous CTNNB1 mutation of 357del24 and P53 staining in only 20% cells.
ACC associated with MEN1 is rare and may occur in familial aggregates.
Nicola Tufton, Lucy Shapiro, Anju Sahdev, Ajith V Kumar, Lee Martin, William M Drake, Scott A Akker and Helen L Storr
Phaeochromocytomas (PCC) and paragangliomas (PGL) are rare in children. A large proportion of these are now understood to be due to underlying germline mutations. Here we focus on succinate dehydrogenase subunit B (SDHB) gene mutation carriers as these tumours carry a high risk of malignant transformation. There remains no current consensus with respect to optimal surveillance for asymptomatic carriers and those in whom the presenting tumour has been resected.
We undertook a retrospective analysis of longitudinal clinical data of all children and adolescents with SDHB mutations followed up in a single UK tertiary referral centre. This included index cases that pre-dated the introduction of surveillance screening and asymptomatic carriers identified through cascade genetic testing. We also conducted a literature review to inform a suggested surveillance protocol for children and adolescents harbouring SDHB mutations.
Clinical outcomes of a total of 38 children are presented: 8 index cases and 30 mutation-positive asymptomatic carriers with 175 patient years of follow-up data. Three of the eight index cases developed metachronous disease and two developed metastatic disease. Of the 30 asymptomatic carriers, 3 were found to have PGLs on surveillance screening.
Surveillance screening was well tolerated in our paediatric cohort and asymptomatic paediatric subjects. Screening can identify tumours before they become secretory and/or symptomatic, thereby facilitating surgical resection and reducing the chance of distant spread. We propose a regular screening protocol commencing at age 5 years in this at-risk cohort of patients.
Weiwei He, Bin Wang, Kaida Mu, Jing Zhang, Yanping Yang, Wei Yao, Sheli Li and Jin-an Zhang
Accumulating data have shown that interleukin-27 (IL27) polymorphisms are linked to the susceptibility of some autoimmune diseases. We assessed whether there was an association between three single-nucleotide polymorphisms (SNPs) of IL27 gene and autoimmune thyroid diseases (AITDs).
Three SNPs (rs153109, rs17855750 and rs181206) of IL27 gene were genotyped by Hi-SNP high-throughput genotyping in 843 patients with AITDs (516 Graves’ disease (GD) and 327 Hashimoto’s thyroiditis (HT)) and 677 healthy controls in Chinese Han population.
Compared with controls, rs153109 displayed significant associations with GD in allele and genotype frequencies (P = 0.002 and P = 0.008, respectively) and rs17855750 displayed significant associations with HT in allele frequencies (P = 0.02), whereas no differences in genotype or allele frequencies were found between AITD patients and controls at rs181206.
Our study, for the first time, showed the significant association of the IL27 gene SNPs with AITD.
Anna C Simcocks, Kayte A Jenkin, Lannie O’Keefe, Chrishan S Samuel, Michael L Mathai, Andrew J McAinch and Deanne H Hryciw
Atypical cannabinoid compounds O-1602 and O-1918 are ligands for the putative cannabinoid receptors G protein-coupled receptor 55 and G protein-coupled receptor 18. The role of O-1602 and O-1918 in attenuating obesity and obesity-related pathologies is unknown. Therefore, we aimed to determine the role that either compound had on body weight and body composition, renal and hepatic function in diet-induced obesity. Male Sprague–Dawley rats were fed a high-fat diet (40% digestible energy from lipids) or a standard chow diet for 10 weeks. In a separate cohort, male Sprague–Dawley rats were fed a high-fat diet for 9 weeks and then injected daily with 5 mg/kg O-1602, 1 mg/kg O-1918 or vehicle (0.9% saline/0.75% Tween 80) for a further 6 weeks. Our data demonstrated that high-fat feeding upregulates whole kidney G protein receptor 55 expression. In diet-induced obesity, we also demonstrated O-1602 reduces body weight, body fat and improves albuminuria. Despite this, treatment with O-1602 resulted in gross morphological changes in the liver and kidney. Treatment with O-1918 improved albuminuria, but did not alter body weight or fat composition. In addition, treatment with O-1918 also upregulated circulation of pro-inflammatory cytokines including IL-1α, IL-2, IL-17α, IL-18 and RANTES as well as plasma AST. Thus O-1602 and O-1918 appear not to be suitable treatments for obesity and related comorbidities, due to their effects on organ morphology and pro-inflammatory signaling in obesity.
Raymond J Rodgers, Jodie C Avery, Vivienne M Moore, Michael J Davies, Ricardo Azziz, Elisabet Stener-Victorin, Lisa J Moran, Sarah A Robertson, Nigel K Stepto, Robert J Norman and Helena J Teede
Many complex diseases exhibit co-morbidities often requiring management by more than one health specialist. We examined cross-speciality issues that ultimately affect the health and wellbeing of patients with polycystic ovary syndrome (PCOS). PCOS was originally described as a reproductive condition but is now recognised to also be a metabolic and psychological condition affecting 8–13% of women of reproductive age. With a four-fold increased risk of type 2 diabetes (DM2), the Population Attributable Risk of DM2 that could be avoided if PCOS were eliminated is a substantial 19–28% of women of reproductive age. To determine the extent to which PCOS is an important consideration in diabetes development, we examined publications, funding, guidelines and predictors of risk of developing DM2.
We found that the topic of PCOS appeared in specialist diabetes journals at only 10% the rate seen in endocrinology journals – about 1 in 500 articles. We found research funding to be substantially less than for diabetes and found that diabetes guidelines and predictive tools for DM2 risk mostly ignore PCOS. This is surprising since insulin resistance in women with PCOS has a different aetiology and additionally women with PCOS are at increased risk of becoming overweight or obese – high risk factors for DM2.
We consider the causes of these concerning anomalies and discuss current activities to address the co-morbidities of PCOS, including the recent development of international guidelines, an international PCOS awareness program and potentially changing the name of PCOS to better reflect its metabolic consequences.
M Jensterle, A Podbregar, K Goricar, N Gregoric and A Janez
Lifestyle measures (LSMs) should be the first-line approach offered for obesity-related functional hypogonadism (FH). When LSMs fail, the role of testosterone replacement treatment (TRT) is unclear. GLP1 receptor agonist liraglutide is linked to progressive and sustained weight loss. A potential direct impact of GLP1 on hypothalamus-pituitary-testicular (HPT) axis was reported in animal models. We aimed to compare the effects of liraglutide and TRT on FH in obese men that had been poor responders to LSM, by means of reversal of FH and weight reduction. We designed a 16-week prospective randomized open-label study with 30 men (aged 46.5 ± 10.9 years, BMI 41.2 ± 8.4 kg/m2, mean ± s.d.) that were randomized to liraglutide 3.0 mg QD (LIRA) or 50 mg of 1% transdermal gel QD (TRT). Sexual function and anthropometric measures were assessed. Fasting blood was drawn for determination of endocrine and metabolic parameters followed by OGTT. Model-derived parameters including HOMAIR and calculated free testosterone (cFT) were calculated. Total testosterone significantly increased in both arms (+5.9 ± 7.2 in TRT vs +2.6 ± 3.5 nmol/L in LIRA) and led to improved sexual function. LIRA resulted in a significant increase of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (P < 0.001 for between-treatment effect). Subjects treated with LIRA lost on average 7.9 ± 3.8 kg compared with a 0.9 ± 4.5 kg loss in TRT (P < 0.001). Metabolic syndrome was resolved in two patients in LIRA and in no subjects in TRT. Liraglutide was superior to TRT in improving an overall health benefit in men with obesity-associated FH after LSM failed.
Corina Verónica Sasso, Flavia Eliana Santiano, Fiorella Campo Verde Arboccó, Leila Ester Zyla, Silvana Noemí Semino, Martin Eduardo Guerrero-Gimenez, Virginia Pistone Creydt, Constanza Matilde López Fontana and Rubén Walter Carón
Epidemiological studies describe estrogens as protectors in the development of colon cancer in postmenopausal women treated with hormone replacement therapy. However, the role of progesterone in colon cancer has been minimally studied and the results are controversial. For the above, the objective of this work was to determine the hormonal regulation exerted by natural ovarian steroids on proliferation and apoptosis in an experimental model of colon cancer in ovariectomized rats treated with 17-beta estradiol and progesterone. Sprague–Dawley rats were exposed to the carcinogen 1,2-dimethylhydrazine to induce colon tumors. Thirty days later, the rats were ovariectomized and treated with estradiol (60 μg/kg), progesterone (10 mg/kg), estradiol plus progesterone (60 μg/kg and 10 mg/kg) or vehicle. We observed no significant differences in colon cancer incidence and tumor multiplicity between the groups. Nevertheless, we observed a decrease in PCNA expression and a greater number of apoptotic index, higher expression of caspase 3, cleaved PARP and cleaved caspase 8 in tumors, confirming the activation of the extrinsic pathway of apoptosis by the combined treatment. In addition, we observed a higher expression of estrogen receptor beta in these tumors. We conclude that the action of both hormones, estradiol and progesterone, is necessary to reduce proliferation and increase apoptosis in colon tumors, probably through estrogen receptor beta activation.