Endocrine Abstracts

Nicotinamide nucleotide transhydrogenase (NNT) is a NADPH-generating mitochondrial proton pump with a central role in mitochondrial antioxidant pathways. Recent studies revealed inactivating NNT mutations in patients with familial glucocorticoid deficiency, indicating a selective susceptibility of the adrenal cortex to NNT deficiency and oxidative stress. Here we explored the potential value of NNT as a therapeutic target in adrenocortical cancer. We delineated the distinct ef...

Mutations in CYP11A1, like those in STAR cause lipoid congenital adrenal hyperplasia manifesting with adrenal and gonadal insufficiencies along with derangements of the renin/angiotensin system. Increased adrenal size is usually a feature of STAR but not of CYP11A1 mutation. Milder forms presenting without all of these features have also been described. We present six patients from four families with CYP11A1 mutations discovered by ...

The index case, born to non-consanguineous British parents, was born with a normal birth weight. He grew along the −2.9 S.D. centile from the age of 2 years. Eczema was diagnosed at the age of 2 weeks. Investigations at 3–4 years of age showed: IGF1<25 ng/ml, IGFBP3 1.29 (N 0.8–3.9), prolactin 265–653 mU/l (N 59–271), GH peak (glucagon test) 17.3 ug/l, normal GH peaks on overnight sampling, and an IGF1<25 ng/ml...

Familial glucocorticoid deficiency (FGD) results from the inability of the adrenal cortex to produce cortisol in response to ACTH stimulation and can be fatal if unrecognised. The disease manifests clinically with increased ACTH and reduced cortisol levels. Our group has recently demonstrated that oxidative stress is implicated in the pathogenesis of this disorder.We previously identified mutations in nicotinamide nucleotide transhydrogenase (NNT) in pat...

Introduction: Loss of function mutations in SGPL1, a key component of sphingolipid metabolism, are associated with accumulation of sphingolipid intermediates giving rise to a multisystemic disease incorporating primary adrenal insufficiency (PAI) and progressive renal and neurological disease. Sphingolipid accumulation is implicated in mitochondrial pathology.Objective: To investigate the impact of SGPL1 deficiency on mitochondrial morphology/ f...

Background: Disturbances of pubertal timing affect >4% of the population and are associated with adverse health outcomes. Studies estimate 60–80% of variation in pubertal onset is genetically determined, but few genetic factors are known. We hypothesise that causal variants will be low-frequency, intermediate-impact variants and will be enriched in populations at the extremes of normal pubertal timing. Families with constitutional delay in growth and puberty (CDGP) ha...

Introduction: In recent years a growing number of gene mutations have been identified which cause a myriad of syndromes having adrenal insufficiency as a core characteristic. The evolution of each syndrome is dependent on the variant and the particular gene affected. Common practice is for candidate genes to be sequenced individually, which can be time consuming and is complicated by overlapping clinical phenotypes. The increasing availability and cost effectiveness of whole e...

Background: Pubertal timing has importance both for the individual, but also for public health. Previous studies estimate that 60–80% of variation in pubertal onset is genetically determined. Recently, a large genome-wide association study (GWAS) meta-analysis identified 42 loci for age-at-menarche (AAM), which explained 3.6–6.1% of the variation in the general population, but causal genes have not been identified.CDGP is defined as pubertal on...

Familial glucocorticoid deficiency is an autosomal recessive disorder characterised by resistance to ACTH of the adrenal cortex, leading to isolated glucocorticoid deficiency and life-threatening hypoglycaemia. Half of all cases are caused by mutations in MC2R, MRAP, MCM4 or STAR. Recent work in our group has identified defects in nicotinamide nucleotide transhydrogenase (NNT) to be causal in a further 10% of cases. NNT generates the high con...

Background: Familial Glucocorticoid Deficiency is an autosomal recessive disorder characterised by ACTH resistance of the adrenal cortex, leading to isolated glucocorticoid deficiency. Causative genes include MC2R, its accessory protein MRAP and StAR which account for 50% of cases. Recently nicotinamide nucleotide transhydrogenase (NNT) has been associated with a further 10% of cases. NNT generates the high concentrations of NADPH in mitochondria necessary for detoxification o...