A novel mutation of KCNJ11 gene in a patient with permanent neonatal diabetes mellitus

Negative emotions, self-care activities on glycemic control in adults with type 2 diabetes: a cross-sectional study

Glycemic control has become a focus of concern among diabetic patients. However, only 26.71% of patients achieved better glycemic control in China. Given the complexity of glycemic control, it is worth investigating the potential mechanisms between negative emotions and glycemic control. A total of 428 participants were recruited from a tertiary hospital (the number of hospital beds>500). They completed questionnaires consisting of demographics, Zung Self-Assessed Anxiety Scale(SAS), Zung Self-Assessed Depression Scale(SDS), and the Summary of Diabetes Self-Care Activities (SDSCA). HbA1 c was used to measure glycemic control. Descriptive analysis, Pearson correlation analysis, and Bootstrap analysis were conducted to analyze data. A total of 428 questionnaires were distributed, with 28 invalid questionnaires (93.46% were valid). Depression and self-care activities (exercise, medication) were associated with glycemic control. At the same time, the Bootstrap analysis revealed that self-care activities (exercise: standardized coefficient β = 0.0181, p < 0.05, medication: standardized coefficient β = 0.0211, p < 0.05) mediated the relationship between depression and glycemic control.

New insights into KATP channel gene mutations and neonatal diabetes mellitus

The ATP-sensitive potassium channel (K_ATP channel) couples blood levels of glucose to insulin secretion from pancreatic β-cells. K_ATP channel closure triggers a cascade of events that results in insulin release. Metabolically generated changes in the intracellular concentrations of adenosine nucleotides are integral to this regulation, with ATP and ADP closing the channel and MgATP and MgADP increasing channel activity. Activating mutations in the genes encoding either of the two types of K_ATP channel subunit (Kir6.2 and SUR1) result in neonatal diabetes mellitus, whereas loss-of-function mutations cause hyperinsulinaemic hypoglycaemia of infancy. Sulfonylurea and glinide drugs, which bind to SUR1, close the channel through a pathway independent of ATP and are now the primary therapy for neonatal diabetes mellitus caused by mutations in the genes encoding K_ATP channel subunits. Insight into the molecular details of drug and nucleotide regulation of channel activity has been illuminated by cryo-electron microscopy structures that reveal the atomic-level organization of the K_ATP channel complex. Here we review how these structures aid our understanding of how the various mutations in the genes encoding Kir6.2 (KCNJ11) and SUR1 (ABCC8) lead to a reduction in ATP inhibition and thereby neonatal diabetes mellitus. We also provide an update on known mutations and sulfonylurea therapy in neonatal diabetes mellitus.

Mutation screening of INS and KCNJ11 genes in Taiwanese children with type 1B diabetic onset before the age of 5 years

Type 1 diabetes (T1D) is caused by β-cell destruction, usually leading to absolute insulin deficiency. T1D is a heterogeneous disease and is divided into two subtypes according to the presence or absence of pancreatic autoantibodies: type 1A (immune mediated) and type 1B (idiopathic). Genes such as KCNJ11 or INS, which play key roles in β-cell function, provide some insight into the pathogenesis of type 1B diabetes. In this study, we screened 110 Taiwanese children (61 males and 49 females) with T1D onset before the age of 5 years for mutations of INS and KCNJ11. We identified one missense heterozygous mutation in KCNJ11 (c.989A>G, p.Y330C) and no INS mutations among 28 probands. This is the first study to screen patients with autoantibody-negative T1D diagnosed before the age of 5 years for INS and KCNJ11 mutations in Taiwan. Although KCNJ11 mutations are always reported in patients with permanent neonatal diabetes, this gene mutation can be detected after 6 months of age. Further studies in other patients with type 1B diabetes and their families are required to elucidate the contributions of the KCNJ11 mutation to the T1D phenotype.