A Case of Congenital Adrenal Hyperplasia due to 3-Beta-Hydroxysteroid Dehydrogenase Deficiency Presented With Acute Liver Failure

Congenital adrenal hyperplasia (CAH) is a group of rare autosomal disorders characterized by a variety of defects in adrenal steroidogenesis. Most cases of CAH are due to an enzyme deficiency in either 21-hydroxylase or 11-beta-hydroxylase. A much rarer form of CAH due to 3-betahydroxysteroid dehydrogenase (3B-HSD) deficiency results in impaired synthesis of all steroid hormones. The clinical presentation of undervirilization in 46 XY patients, hyponatremia, hyperkalemia, and recurrent hypoglycemia in 3B-HSD deficiency cases is well described in the literature. We describe a neonate with 3B-HSD deficiency that presented with ambiguous genitalia and hypoglycemia and was found to have comorbid coagulopathy, cholestasis, and direct hyperbilirubinemia with liver failure that resolved with glucocorticoid and mineralocorticoid treatment. Prompt recognition of this disease is imperative for timely intervention.

Insulin-Induced Recurrent Hypoglycemia Up-Regulates Glucose Metabolism in the Brain Cortex of Chemically Induced Diabetic Rats

Diabetes is a chronic metabolic disease that seriously compromises human well-being. Various studies highlight the importance of maintaining a sufficient glucose supply to the brain and subsequently safeguarding cerebral glucose metabolism. The goal of the present work is to clarify and disclose the metabolic alterations induced by recurrent hypoglycemia in the context of long-term hyperglycemia to further comprehend the effects beyond brain harm. To this end, chemically induced diabetic rats underwent a protocol of repeatedly insulin-induced hypoglycemic episodes. The activity of key enzymes of glycolysis, the pentose phosphate pathway and the Krebs cycle was measured by spectrophotometry in extracts or isolated mitochondria from brain cortical tissue. Western blot analysis was used to determine the protein content of glucose and monocarboxylate transporters, players in the insulin signaling pathway and mitochondrial biogenesis and dynamics. We observed that recurrent hypoglycemia up-regulates the activity of mitochondrial hexokinase and Krebs cycle enzymes (namely, pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase and succinate dehydrogenase) and the protein levels of mitochondrial transcription factor A (TFAM). Both insults increased the nuclear factor erythroid 2–related factor 2 (NRF2) protein content and induced divergent effects in mitochondrial dynamics. Insulin-signaling downstream pathways were found to be down-regulated, and glycogen synthase kinase 3 beta (GSK3β) was found to be activated through both decreased phosphorylation at Ser9 and increased phosphorylation at Y216. Interestingly, no changes in the levels of cAMP response element-binding protein (CREB), which plays a key role in neuronal plasticity and memory, were caused by hypoglycemia and/or hyperglycemia. These findings provide experimental evidence that recurrent hypoglycemia, in the context of chronic hyperglycemia, has the capacity to evoke coordinated adaptive responses in the brain cortex that will ultimately contribute to sustaining brain cell health.

Genetic pathogenesis, diagnosis, and treatment of short-chain 3-hydroxyacyl-coenzyme A dehydrogenase hyperinsulinism

Congenital hyperinsulinism (CHI), a major cause of persistent and recurrent hypoglycemia in infancy and childhood. Numerous pathogenic genes have been associated with 14 known genetic subtypes of CHI. Adenosine triphosphate-sensitive potassium channel hyperinsulinism (KATP-HI) is the most common and most severe subtype, accounting for 40–50% of CHI cases. Short-chain 3-hydroxyacyl-coenzyme A dehydrogenase hyperinsulinism (SCHAD-HI) is a rare subtype that accounts for less than 1% of all CHI cases that are caused by homozygous mutations in the hydroxyacyl-coenzyme A dehydrogenase (HADH) gene. This review provided a systematic description of the genetic pathogenesis and current progress in the diagnosis and treatment of SCHAD-HI to improve our understanding of this disease.

Hypoglycemia, an obstacle to achieving glycemic control. Importance of blood glucose self-monitoring

Hypoglycemia is a well-known factor, limiting the patient's ability to achieve adequate glycemic control, and capable of causing a number of car-diovascular diseases (CVDs). Recurrent hypoglycemia may result in severe, potentially fatal complication of diabetes mellitus (DM), the impaired hypoglycemia awareness, raising the risk of severe hypoglycemia up up to six times. Measuring blood glucose levels is a universally accepted com-ponent of glycemic control and one of the strategies for prevention of hypoglycemia, along with the structured patient education in DM manage-ment and the use of modern hypoglycemic medications. Prevention of severe hypoglycemia may be important for prevention of CVDs in patients with DM.

Somatostatin Receptor Antagonism Reverses Glucagon Counterregulatory Failure in Recurrently Hypoglycemic Male Rats

Recent antecedent hypoglycemia is a known source of defective glucose counter-regulation in diabetes; the mechanisms perpetuating the cycle of progressive α-cell failure and recurrent hypoglycemia remain unknown. Somatostatin has been shown to suppress the glucagon response to acute hypoglycemia in rodent models of type 1 diabetes. We hypothesized that somatostatin receptor 2 antagonism (SSTR2a) would restore glucagon counterregulation and delay the onset of insulin-induced hypoglycemia in recurrently hypoglycemic, nondiabetic male rats. Healthy, male, Sprague–Dawley rats (n = 39) received bolus injections of insulin (10 U/kg, 8 U/kg, 5 U/kg) on 3 consecutive days to induce hypoglycemia. On day 4, animals were then treated with SSTR2a (10 mg/kg; n = 17) or vehicle (n = 12) 1 hour prior to the induction of hypoglycemia using insulin (5 U/kg). Plasma glucagon level during hypoglycemia was ~30% lower on day 3 (150 ± 75 pg/mL; P < .01), and 68% lower on day 4 in the vehicle group (70 ± 52 pg/mL; P < .001) compared with day 1 (219 ± 99 pg/mL). On day 4, SSTR2a prolonged euglycemia by 25 ± 5 minutes (P < .05) and restored the plasma glucagon response to hypoglycemia. Hepatic glycogen content of SSTR2a-treated rats was 35% lower than vehicle controls after hypoglycemia induction on day 4 (vehicle: 20 ± 7.0 vs SSTR2a: 13 ± 4.4 µmol/g; P < .01). SSTR2a treatment reverses the cumulative glucagon deficit resulting from 3 days of antecedent hypoglycemia in healthy rats. This reversal is associated with decreased hepatic glycogen content and delayed time to hypoglycemic onset. We conclude that recurrent hypoglycemia produces glucagon counterregulatory deficiency in healthy male rats, which can be improved by SSTR2a.

Glutamate Dehydrogenase as a Promising Target for Hyperinsulinism Hyperammonemia Syndrome Therapy.

: Hyperinsulinism-hyperammonemia syndrome (HHS) is a rare disease characterized by recurrent hypoglycemia and persistent elevation of plasma ammonia, and it can lead to severe epilepsy and permanent brain damage. It has been demonstrated that functional mutations of glutamate dehydrogenase (GDH), an enzyme in the mitochondrial matrix, are responsible for the HHS. Thus, GDH has become a promising target for the small molecule therapeutic intervention of HHS. Several medicinal chemistry studies are currently aimed at GDH, however, to date, none of the compounds reported has been entered clinical trials. This perspective summarizes the progress in the discovery and development of GDH inhibitors, including the pathogenesis of HHS, potential binding sites, screening methods, and research models. Future therapeutic perspectives are offered to provide a reference for discovering potent GDH modulators and encourage additional research that will provide more comprehensive guidance for drug development.

Brain Tissue Low-Level Mosaicism for MTOR Mutation Causes Smith–Kingsmore Phenotype with Recurrent Hypoglycemia—A Novel Phenotype and a Further Proof for Testing of an Affected Tissue

De novo somatic variants in genes encoding components of the PI3K–AKT3–mTOR pathway, including MTOR, have been linked to hemimegalencephaly or focal cortical dysplasia. Similarly to other malformations of cortical development, this condition presents with developmental delay and intractable epilepsy, often necessitating surgical treatment. We describe a first patient with the Smith–Kingsmore syndrome phenotype with recurrent hypoglycemia caused by low-level mosaic MTOR mutation restricted to the brain. We provide discussion on different aspects of somatic mosaicism. Deep exome sequencing combined with a variant search in multiple tissues and careful phenotyping may constitute a key to the diagnosis of the causes of rare brain anomalies.

Beyond the barriers of the use of continuous subcutaneous insulin therapy in type 1 diabetes: a new opportunity from catheter-less insulin pumps

Although it represents a valid alternative for patients with type 1 diabetes (T1DM) with insufficient glycemic control and/or with recurrent hypoglycemia, insulin pump therapy (Continuous Subcutaneous Insulin Infusion, CSII) in Italy is nowadays still relatively uncommon. The following review aims to investigate the barriers that limit the transition to CSII and the reasons behind the widespread cases of drop-out, particularly evident in younger patients. Among the interventions that could contribute to the solution of the problem, catheter-less insulin pumps (or patch-pumps) will be described: a tool potentially able to reduce, if not eliminate, some of the main obstacles encountered by patients. In particular, a new opportunity has become available today thanks to the evolution of the generation of catheter-less insulin pumps represented by Accu-Chek® Solo (Roche Diabetes Care GmbH), therefore three clinical cases of patients with T1DM undergoing therapy with the Accu-Chek® Solo insulin pump will be presented and discussed herein.