Evaluating Eating Behaviour, Energy Homeostasis, and Obesity in Childhood-Onset Craniopharyngioma: A Feasibility Study.

INTRODUCTION: Craniopharyngiomas are rare brain tumours (incidence 1.1-1.7 cases/million/year). Although non-malignant, craniopharyngioma causes major endocrine and visual morbidities including hypothalamic obesity, yet mechanisms leading to obesity are poorly understood. This study investigated the feasibility and acceptability of eating behaviour measures in patients with craniopharyngioma to inform the design of future trials. METHODS: Patients with childhood-onset craniopharyngioma and controls matched for sex, pubertal stage, and age were recruited. After an overnight fast, participants received the following measures: body composition, resting metabolic rate, oral glucose tolerance test including magnetic resonance imaging (patients only), appetite ratings, eating behaviour, and quality of life questionnaires, ad libitum lunch, and an acceptability questionnaire. Data are reported as median ± IQR, with effect size measure (Cliff's delta) and Kendall's tau for correlations, due to the small sample size. RESULTS: Eleven patients (median age = 14 years; 5 F/6 M) and matched controls (median age = 12 years; 5 F/6 M) were recruited. All patients had received surgery, and 9/11 also received radiotherapy. Hypothalamic damage post-surgery was graded (Paris grading): grade 2 n = 6; grade 1 n = 1; grade 0 n = 2. The included measures were deemed highly tolerable by participants and their parent/carers. Preliminary data suggest a difference in hyperphagia between patients and controls (d = 0.5), and a relationship between hyperphagia with body mass index standard deviation score (BMISDS) in patients (τ = 0.46). DISCUSSION: These findings demonstrate that eating behaviour research is feasible and acceptable to craniopharyngioma patients and there is an association between BMISDS and hyperphagia in patients. Thus, food approach and avoidance behaviours may be useful targets for interventions to manage obesity in this patient group.

Case report: Molecular characterisation of adipose-tissue derived cells from a patient with ROHHAD syndrome.

There have been over 100 cases of Rapid-onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation (ROHHAD) syndrome reported, but there is currently no curative treatment for children with this condition. We aimed to better characterise adipose cells from a child with ROHHAD syndrome. We isolated pre-adipocytes from a 4 year-old female patient with ROHHAD syndrome and assessed proliferation rate of these cells. We evaluated levels of DLP-Pref-1(pre-adipocyte marker) using western blotting, and concentrations of interleukin-6(IL-6) using ELISA. We performed next-generation sequencing (NGS) and bioinformatic analyses on these cells compared to tissue from an age/sex-matched control. The two most up-/down-regulated genes were validated using QPCR. We successfully isolated pre-adipocytes from a fat biopsy, by confirming the presence of Pref-1 and differentiated them to mature adipocytes. Interleukin 6, (Il-6) levels were 5.6-fold higher in ROHHAD cells compared to a control age/sex-matched biopsy. NGS revealed 25,703 differentially expressed genes (DEGs) from ROHHAD cells vs. control of which 2,237 genes were significantly altered. The 20 most significantly up/down-regulated genes were selected for discussion. This paper describes the first transcriptomic analysis of adipose cells from a child with ROHHAD vs. normal control adipose tissue as a first step in identifying targetable pathways/mechanisms underlying this condition with novel therapeutic interventions.

Rapid-onset obesity, hypothalamic dysfunction, hypoventilation, and autonomic dysregulation syndrome - neuro-endocrine tumours (ROHHAD-NET): case series and learning points.

OBJECTIVES: Rapid-onset obesity with hypoventilation, hypothalamic dysfunction, autonomic dysregulation (ROHHAD) is a rare syndrome associated with high morbidity and mortality. Diagnosis is often challenging. We describe three cases of ROHHAD with heterogeneous presentations but some consistent clinical features, including hyperprolactinaemia at diagnosis. We highlight when the diagnosis of ROHHAD should be considered at an early stage. CASE PRESENTATION: All three patients presented between 4 and 6 years old with rapid-onset obesity. They all have central hypoventilation requiring nocturnal BiPAP, varying degrees of hypothalamic dysfunction with hyperprolactinaemia being a consistent feature, and autonomic dysfunction. One patient has a neuro-endocrine tumour (NET) and two have glucose dysregulation. CONCLUSIONS: High prolactin was a consistent early feature. Central hypoventilation and NET may present later and therefore regular sleep studies and screening for NETs are required. A high suspicion of ROHHAD is warranted in patients with rapid, early-onset obesity and hyperprolactinaemia without structural pituitary abnormality.

Rituximab therapy in ROHHAD(NET) syndrome.

OBJECTIVES: Rapid-onset obesity with hypoventilation, hypothalamic dysfunction, autonomic dysregulation, and neural-crest tumour (ROHHAD(NET)) is a rare syndrome presenting in early childhood associated with high morbidity and mortality. There is no specific diagnostic biomarker and diagnosis is based on clinical features. An autoimmune origin has been postulated. CASE PRESENTATION: Management is largely supportive. We report a case of a five-year old female who presented in respiratory arrest after 6-months of rapid weight gain. She had central hypoventilation, central diabetes insipidus, growth hormone deficiency and hyperprolactinaemia. She displayed elevated interleukin-6 levels on cytokine serology which normalised after rituximab treatment. After rituximab treatment, her weight reduced significantly from greatly above the 99.6th to the 50th centile in 12 months. CONCLUSIONS: This response possibly reflects an underlying, immune-inflammatory pathology driving excess adiposity in this condition. Potentially, other aspects of ROHHAD(NET) may be mediated through autoimmune dysregulation in which case rituximab may provide benefits for prognosis and survival.

Treatment of Barth Syndrome by Cardiolipin Manipulation (CARDIOMAN) With Bezafibrate: Protocol for a Randomized Placebo-Controlled Pilot Trial Conducted in the Nationally Commissioned Barth Syndrome Service.

BACKGROUND: Barth syndrome is a rare, life-threatening, X-linked recessive genetic disease that predominantly affects young males and is caused by abnormal mitochondrial lipid metabolism. Currently, there is no definitive treatment for Barth syndrome other than interventions to ameliorate acute symptoms, such as heart failure, cardiac arrhythmias, neutropenia, and severe muscle fatigue. Previous mechanistic studies have identified the lipid-lowering drug bezafibrate as a promising potential treatment; however, to date, no human trials have been performed in this population. OBJECTIVE: The aim of this study is to determine whether bezafibrate (and resveratrol in vitro) will increase mitochondrial biogenesis and potentially modify the cellular ratio of monolysocardiolipin (MLCL) to tetralinoleoyl-cardiolipin (L4-CL), ameliorating the disease phenotype in those living with the disease. METHODS: The CARDIOMAN (Cardiolipin Manipulation) study is a UK single-center, double-blinded, randomized, placebo-controlled crossover study investigating the efficacy of bezafibrate in participants with Barth syndrome. Treatment was administered in two 15-week phases with a minimum washout period of 1 month between the phases where no treatment was administered. The primary outcome is peak oxygen consumption (VO2 peak). Secondary outcomes include MLCL/L4-CL ratio and CL profile in blood cells, amino acid expression, phosphocreatine to adenosine triphosphate ratio in cardiac muscle and skeletal muscle oxidative function on phosphorus-31 magnetic resonance spectroscopy, quality of life using the Pediatric Quality of Life Inventory questionnaire, absolute neutrophil count, cardiac function and rhythm profiles at rest and during exercise, and mitochondrial organization and function assessments. Outcomes were assessed at baseline and during the final week of each treatment phase. RESULTS: A total of 12 patients were scheduled to participate across three consecutive research clinics between March and April 2019. In total, 11 participants were recruited, and the follow-up was completed in January 2020. Data analysis is ongoing, with publication expected in 2021. CONCLUSIONS: This trial was approved by the United Kingdom National Research Ethics Service Committee and the Medicines and Healthcare products Regulatory Agency. The feasibility of the CARDIOMAN study will help to inform the future conduct of randomized controlled trials in rare disease populations as well as testing the efficacy of bezafibrate as a potential treatment for the disease and advancing the mechanistic understanding of Barth syndrome. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN): 58006579; https://www.isrctn.com/ISRCTN58006579. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/22533.

Nutrition and physical activity intervention for families with familial hypercholesterolaemia: protocol for a pilot randomised controlled feasibility study.

BACKGROUND: Untreated heterozygous familial hypercholesterolaemia (FH) causes high low-density lipoprotein cholesterol (LDL-C) levels and increased cardiovascular disease (CVD) risk. Despite pharmacological treatment, many treated individuals remain at higher CVD risk than non-affected individuals. This may be due to LDL-C targets not being met and presence of other CVD risk factors. Adhering to dietary and physical activity (PA) recommendations developed for individuals with FH may further reduce CVD risk. However, there is insufficient research to support the efficacy of adhering to these guidelines on LDL-C and other CVD risk factors. The need for studies to investigate the effectiveness of nutrition and PA interventions in the FH population has been widely recognised and recommended. This paper describes the protocol of a pilot, randomised controlled trial designed to evaluate the feasibility and acceptability of a specifically developed nutrition and PA intervention aimed at improving the dietary intakes and PA levels of families with FH. METHODS: A two-arm randomised waitlist-controlled pilot trial will be conducted across three National Health Service (NHS) sites in England, UK. Twenty-four young people with FH, aged 10-18 years, and their affected parent, will be recruited and randomly assigned to the intervention or waitlist and usual care control. The primary aim is to provide evidence for the feasibility and acceptability of delivering the intervention, explored quantitatively (rates of recruitment, retention and outcome measure completeness) and qualitatively (qualitative interviews). The secondary aim is to provide evidence for the potential efficacy of the intervention on dietary intake, PA, sedentary time, body composition, CVD risk factors and quality of life determined at baseline and endpoint assessments. The intervention will involve an hour-long consultation with a dietitian at baseline and four follow-up contacts across the 12-week intervention. It has been specifically developed for use with individuals with FH and incorporates behavioural change techniques to target identified enablers and barriers to adherence in this population. DISCUSSION: This trial will estimate the feasibility and acceptability of the nutrition and PA intervention delivered to young people and parents with FH. If appropriate, this study can be used to inform the design of an adequately powered definitive trial. TRIAL REGISTRATION: ISRCTN, ISRCTN24880714. Registered 07/06/2018, http://www.isrctn.com/ISRCTN24880714.

How do the experiences and beliefs of adults and children with heterozygous familial hypercholesterolaemia influence their adherence to treatment? A systematic review of qualitative evidence protocol.

BACKGROUND: Heterozygous familial hypercholesterolaemia (FH) is a genetic disorder characterised by elevated levels of low density lipoprotein (LDL) cholesterol from birth, estimated to affect 1 in 250 of the UK population. Left untreated, FH substantially increases an individual's risk of premature coronary heart disease (CHD) and associated mortality. This risk can be minimised with timely diagnosis and successful treatment with medication and lifestyle changes, as advocated in national and international guidelines. Despite these recommendations, the limited research available suggests adherence to treatment may be sub-optimal. This review will identify and synthesise the available qualitative research regarding the experiences and beliefs of adults and children with FH in relation to their condition and its treatment, and the influence of these upon treatment adherence. METHODS: The following electronic databases will be searched from their inception: Cochrane library, MEDLINE, Embase, PsycINFO (via OVID) and CINAHL. Studies available in English and reporting primary qualitative data will be included. Database searching will be supplemented with searches in relevant specialist websites. The references of identified papers will also be hand searched. Two reviewers will independently screen titles and abstracts of identified studies, with full texts of potentially relevant papers retrieved for review against pre-defined inclusion and exclusion criteria. The Critical Appraisal Skills Programme (CASP) Qualitative Research checklist will be used to assess quality of the included studies, and the results will be taken into consideration when reporting the findings. A data extraction tool will be created for use in this review to extract study findings relevant to the review questions. A thematic synthesis approach will be taken to analyse the results. DISCUSSION: Adherence to treatment recommendations is crucial for the successful management of FH and subsequent decrease in risk of CHD later in life. Common identified themes could provide an understanding of the beliefs and experiences which influence adherence to treatment recommendations and provide an insight into perceived barriers and facilitators. The findings are intended to be used in the development of future interventions or guidelines regarding treatment of children and adults with FH. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number: CRD42018085946.

Insulin-like growth factor-II in adipocyte regulation: depot-specific actions suggest a potential role limiting excess visceral adiposity.

The IGF system has an important role in growth and development. IGF-II is a recognized fetal growth promoter. However, its physiological postnatal role remains uncertain, although it is maintained in the circulation at a substantially high level throughout life. IGF-II has been strongly linked to obesity in genetic studies, and more recent evidence suggests a metabolic role. We examined fat depot differences in IGF-II's action on differentiation and metabolism. We speculate a specific effect on visceral adipocytes in relation to the differential distribution of insulin receptors between visceral and subcutaneous fat depots. We used a previously established adipocyte, cell culture system of matched pairs of visceral and subcutaneous fat biopsies from 20 normal weight children undergoing routine surgery for nonmalignant, nonseptic conditions. Preadipocytes were differentiated for 14 days in the presence or absence of IGF-II. Oil Red O staining, Western blotting, and reverse transcription polymerase chain reaction techniques were employed to assess levels of adipogenesis markers and levels of the insulin receptor and insulin receptor isoforms. Our data indicate that IGF-II promotes preadipocyte differentiation in subcutaneous preadipocytes but showed a protective, opposing effect restricting visceral preadipocyte differentiation, confirmed by reductions in the differentiation markers peroxisome proliferator-activated receptor gamma and adiponectin and in triglyceride staining. Additionally, IGF-II reduced mRNA expression of the insulin receptor in adipocytes and downregulated insulin receptor isoform A and glucose transporter 4 abundance and corresponding glucose uptake in visceral adipocytes. In conclusion, IGF-II is a regulator of preadipocyte differentiation and metabolism by acting as a differential modulator of fat accumulation favoring less visceral fat deposition in children.

Polycystic Kidney Disease with Hyperinsulinemic Hypoglycemia Caused by a Promoter Mutation in Phosphomannomutase 2.

Hyperinsulinemic hypoglycemia (HI) and congenital polycystic kidney disease (PKD) are rare, genetically heterogeneous disorders. The co-occurrence of these disorders (HIPKD) in 17 children from 11 unrelated families suggested an unrecognized genetic disorder. Whole-genome linkage analysis in five informative families identified a single significant locus on chromosome 16p13.2 (logarithm of odds score 6.5). Sequencing of the coding regions of all linked genes failed to identify biallelic mutations. Instead, we found in all patients a promoter mutation (c.-167G>T) in the phosphomannomutase 2 gene (PMM2), either homozygous or in trans with PMM2 coding mutations. PMM2 encodes a key enzyme in N-glycosylation. Abnormal glycosylation has been associated with PKD, and we found that deglycosylation in cultured pancreatic ß cells altered insulin secretion. Recessive coding mutations in PMM2 cause congenital disorder of glycosylation type 1a (CDG1A), a devastating multisystem disorder with prominent neurologic involvement. Yet our patients did not exhibit the typical clinical or diagnostic features of CDG1A. In vitro, the PMM2 promoter mutation associated with decreased transcriptional activity in patient kidney cells and impaired binding of the transcription factor ZNF143. In silico analysis suggested an important role of ZNF143 for the formation of a chromatin loop including PMM2 We propose that the PMM2 promoter mutation alters tissue-specific chromatin loop formation, with consequent organ-specific deficiency of PMM2 leading to the restricted phenotype of HIPKD. Our findings extend the spectrum of genetic causes for both HI and PKD and provide insights into gene regulation and PMM2 pleiotropy.

Mutations in NLRP5 are associated with reproductive wastage and multilocus imprinting disorders in humans.

Human-imprinting disorders are congenital disorders of growth, development and metabolism, associated with disturbance of parent of origin-specific DNA methylation at imprinted loci across the genome. Some imprinting disorders have higher than expected prevalence of monozygotic twinning, of assisted reproductive technology among parents, and of disturbance of multiple imprinted loci, for which few causative trans-acting mutations have been found. Here we report mutations in NLRP5 in five mothers of individuals affected by multilocus imprinting disturbance. Maternal-effect mutations of other human NLRP genes, NLRP7 and NLRP2, cause familial biparental hydatidiform mole and multilocus imprinting disturbance, respectively. Offspring of mothers with NLRP5 mutations have heterogenous clinical and epigenetic features, but cases include a discordant monozygotic twin pair, individuals with idiopathic developmental delay and autism, and families affected by infertility and reproductive wastage. NLRP5 mutations suggest connections between maternal reproductive fitness, early zygotic development and genomic imprinting.

The HNF4A R76W mutation causes atypical dominant Fanconi syndrome in addition to a ß cell phenotype.

BACKGROUND: Mutation specific effects in monogenic disorders are rare. We describe atypical Fanconi syndrome caused by a specific heterozygous mutation in HNF4A. Heterozygous HNF4A mutations cause a beta cell phenotype of neonatal hyperinsulinism with macrosomia and young onset diabetes. Autosomal dominant idiopathic Fanconi syndrome (a renal proximal tubulopathy) is described but no genetic cause has been defined. METHODS AND RESULTS: We report six patients heterozygous for the p.R76W HNF4A mutation who have Fanconi syndrome and nephrocalcinosis in addition to neonatal hyperinsulinism and macrosomia. All six displayed a novel phenotype of proximal tubulopathy, characterised by generalised aminoaciduria, low molecular weight proteinuria, glycosuria, hyperphosphaturia and hypouricaemia, and additional features not seen in Fanconi syndrome: nephrocalcinosis, renal impairment, hypercalciuria with relative hypocalcaemia, and hypermagnesaemia. This was mutation specific, with the renal phenotype not being seen in patients with other HNF4A mutations. In silico modelling shows the R76 residue is directly involved in DNA binding and the R76W mutation reduces DNA binding affinity. The target(s) selectively affected by altered DNA binding of R76W that results in Fanconi syndrome is not known. CONCLUSIONS: The HNF4A R76W mutation is an unusual example of a mutation specific phenotype, with autosomal dominant atypical Fanconi syndrome in addition to the established beta cell phenotype.