Glucokinase maturity-onset diabetes of the young (GCK-MODY) represents a distinct subgroup of MODY that does not require hyperglycemia-lowering treatment and has very few diabetes-related complications. Three patients from two families who presented with clinical signs of GCK-MODY were evaluated. Whole-exome sequencing was performed and the effects of the identified mutations were assessed using bioinformatics tools, such as PolyPhen-2, SIFT, and in silico modeling. We identified two mutations: p.Leu30Pro and p.Ser383Leu. In silico analyses predicted that these mutations result in structural conformational changes, protein destabilization, and thermal instability. Our findings may inform future GCK-MODY diagnosis; furthermore, the two mutations detected in two Korean families with GCK-MODY improve our understanding of the genetic basis of the disease.
Computational Biology ; Computer Simulation ; Diabetes Complications ; Diabetes Mellitus, Type 2* ; Diagnosis ; Glucokinase* ; Humans

Congenital hyperinsulinism (CHI), the most important cause of hyperglycemia in early infancy, is a heterogenous disease characterized by dysregulation of insulin secretion. Mutations in five proteins have been associated with CHI: sulfonyl urea receptor 1; Kir 6.2; glucokinase; glutamate dehydrogenase and mitochondrial enzyme short-chain 3-hydroxyacyl-coenzyme A dehydrogenase. Early recognition of hypoglycemia, diagnosis of CHI and appropriate management of the hypoglycemia are of the utmost importance to prevent neurologic damage. We report a case of persistent hyperinsulinemic hypoglycemia in 8-month-old male infant. This patient has no mutation in previously mentioned genes. Treatment with diazoxide was successful without any severe side effects in this patient.
Congenital Hyperinsulinism* ; Diagnosis ; Diazoxide* ; Glucokinase ; Glutamate Dehydrogenase ; Humans ; Hyperglycemia ; Hyperinsulinism ; Hypoglycemia ; Infant ; Insulin ; Male ; Oxidoreductases ; Urea

Diabetes mellitus is a chronic syndrome of abnormal metabolism, determined by interaction of multifactorial genetic and environmental factors. Some specific types of diabetes, such as MODY, Leprechaunism, lipoatrophic diabetes, and Rabson-Mendenhall syndrome, are monogenic forms of diabetes and are inherited as a Mendelian pattern. The article reviews the research development of these Mendelian inherited diabetes will be reviewed.
Diabetes Mellitus, Type 2 ; etiology ; genetics ; Genetic Predisposition to Disease ; Glucokinase ; genetics ; Humans ; Mutation ; genetics

Maturity onset diabetes of the young (MODY) is a monogenic autosomal dominant inherited disease. Its clinical manifestations are asymptomatic with slightly elevated fasting blood glucose and few complications. This paper reports a novel mutation W257R in glucokinase () gene from a Chinese patient with MODY. Heterozygous mutation c.769T>C (p.W257R) in exon 7 of gene (Chr744187343) was found in the proband, her father and brother. This W257R mutation was first reported in Chinese population.
China ; Diabetes Mellitus, Type 2 ; genetics ; Female ; Glucokinase ; genetics ; Humans ; Male ; Mutation ; Pedigree

Maturity-onset diabetes of the young (MODY) is a heterogenous form of diabetes characterized by the early onset of diabetes, autosomal dominant inheritance, and impaired insulin secretion. MODY is mostly caused by mutations of the hepatocyte nuclear factor 1-alpha (HNF1-alpha) and glucokinase genes in Caucasians. However most Korean, Japanese, and Chinese patients with MODY do not express known MODY genes. The cause of MODY in Asians has not yet been elucidated clearly. This review focuses on studies on Asian patients with MODY.
Asian Continental Ancestry Group ; Diabetes Mellitus, Type 2 ; Glucokinase ; Hepatocyte Nuclear Factor 1-alpha ; Humans ; Insulin ; Wills

We studied the anti-diabetic effects of medicinal herb water extracts on expression of hepatic glucokinase (GCK), pyruvate dehydrogenase (PDH), and acetyl-CoA carboxylase (ACC) mRNA. The medicinal herbs used for experiments were Cornus officinalis (CO), Paeonia suffruticosa Andrews (PSA), Discorea japonica Thunb. (DJ), Rehmannia glutinosa (RG), Lycium chinense (LC), and Pyrus pyrifolia (PP). For GCK mRNA expression, CO, RG, and LC water extracts exhibited a more effective activity than other extracts. Cells treated with RG and LC water extracts showed an increase in expression of PDH mRNA to 191% and 124%, respectively, compared to control. Expression of ACC mRNA was significantly higher in LC water extract. These data indicate that CO, RG, and LC water extracts stimulates expression of hepatic GCK, PDH, and ACC mRNA.
Acetyl Coenzyme A ; Acetyl-CoA Carboxylase ; Cornus ; Glucokinase ; Lycium ; Oxidoreductases ; Paeonia ; Plants, Medicinal ; Pyrus ; Pyruvic Acid ; Rehmannia ; RNA, Messenger ; Water

OBJECTIVES: Mutations in the glucokinase (GCK) gene are considered a possible cause of maturity-onset diabetes of the young. The purpose of this study was to evaluate the contribution of this gene to the development of non insulin dependent diabetes mellitus (NIDDM), gestational diabetes mellitus (GDM) and post-renal transplantation diabetes mellitus (PTDM). METHOD: Identification of GCK mutation was attempted on 39 NIDDM patients, 2 GDM patients and 58 selected renal allograft recipients with PTDM and 45 normal controls. The exons in the GCK gene were examined by polymerase chain reaction (PCR), followed by analysis of single-stranded DNA conformational polymorphism (SSCP). The abnormal bands were also confirmed by DNA sequenc- ing analysis. The exons of affected family members were also investigated for mutations of the GCK gene. RESULTS: Two of the 58 PTDM patients (3.4%) were found to have GCK mutations. One had the mutation on exon 5 and the other on intron 7. One control subject had the mutation on intron 9. The mutation of exon 5 was identified as a substitution of CCT(proline) for CTT (leucine) at codon 164, which has not ever reported before. The family members of the PTDM patient with mutation of exon 5 were analyzed by PCR followed by SSCP, and two of them revealed the same mutation. The abnormal band on the SSCP analysis of exon 7 was identified as the insertion of base C/T at the 39th nucleotide in intron 7. Two family members of this patients also had same band on SSCP. The one mutation of 45 normal controls was CT located at the 8th nucleotide in intron 9, which was a common polymorphism. CONCLUSON: We found GCK mutations in subjects with PTDM and we speculate that these mutations may be one of the contributing cause of PTDM.
Allografts ; Codon ; Diabetes Mellitus ; Diabetes Mellitus, Type 2* ; Diabetes, Gestational ; DNA ; DNA, Single-Stranded ; Exons ; Female ; Glucokinase* ; Humans ; Insulin ; Introns ; Polymerase Chain Reaction ; Polymorphism, Single-Stranded Conformational ; Pregnancy

Rhemannie Radix Preparata (RRP) has been previously employed in traditional oriental medicine as a treatment for diabetic thirst and improving blood flow. The aim of this study was to evaluate its hypoglycemic control by assaying the activities of key enzymes of carbohydrate metabolism in streptozotocin-(STZ)-induced diabetic rats. Further, RRP extracts were prepared in water (RRPW), in 50% ethanol (RRP50), and in 100% ethanol (RRP100), respectively, and compared for their actions in diabetic rats. The oral treatment of RRP (5 mg/kg b.w./d) to diabetic rats for 21 days resulted in a significant decline in blood glucose by 67% compared to diabetic control rats (P < 0.05). The altered activities of glucokinase, glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), and acetyl CoA carboxylase (ACC) in the livers of diabetic rats were reversed significantly to near-normal levels by the administration of RRP (P < 0.05). Among the three RRP extracts, RRP100 was the most effective in terms of hypoglycemic action. However, the administration of RRP to diabetic rats did not improve insulin production. The modulatory effects of RRP100 on the attenuation of carbohydrate enzyme activities appear to hold promise for widespread use for the treatment of diabetes in the future.
Acetyl-CoA Carboxylase ; Animals ; Blood Glucose ; Carbohydrate Metabolism ; Ethanol ; Glucokinase ; Gluconates ; Glucosephosphate Dehydrogenase ; Hypoglycemic Agents ; Insulin ; Liver ; Medicine, East Asian Traditional ; Phosphogluconate Dehydrogenase ; Rats ; Thirst ; Water

Glucokinase is expressed only in both liver and pancreatic beta cells and has a key role in the regulation of glucose metabolism in these tissues. A number of gene defects associated with glucokinase gene and the cause of non-insulin-dependent diabetes mellitus are known, and the defects along the -30bp promoter site in particular are thought to be related to diabetes and glucose intolerance. To research on gene study related to diabetes, we looked into the relationship between the variation at -30bp of pancreatic beta cell specific glucokinase gene promoter and gestational diabetes mellitus(GDM) in Korea. METHODS: Forty patients with GDM and 62 normal controls were studied. Genomic DNA was extracted from peripheral leukocyte of patients with GDM and normal controls. The nucleotide variation at -30 bp of pancreatic beta cell specific glucokinase gene promoter was analyzed by PCR-SSCP methods. The sequences of amplified DNA were confirmed with direct sequencing method. The clinical features and the response of insulin secretion to oral glucose were analyzed between patients with GDM according to genotypes. RESULTS: Allelic frequency of position -30 bp of pancreatic beta cell specific glucokinase gene promoter did not differ between patients with GDM and normal subjects. However the frequency of G/A and A/A genotypes seemed to show a higher tendency in patients with GDM compare to the normal subjects. Clinical features, insulin response to oral glucose did not differ according to the type of variation at -30bp of pancreatic beta cell specific glucokinase gene promoter. CONCLUSION: These data suggested that the variation at -30 bp of pancreatic beta cell specific glucokinase gene promoter in patients with GDM are unlikely to be one of the possibilities of the genetic factors in the development of GDM. Therefore more sophisticated studies will be needed to elucidate the role of variation at -30bp of pancreatic beta cell specific glucokinase gene promoter in the insulin secretion to oral glucose.
Diabetes Mellitus, Type 2 ; Diabetes, Gestational* ; DNA ; Female ; Genotype ; Glucokinase* ; Glucose ; Glucose Intolerance ; Humans ; Insulin ; Insulin-Secreting Cells ; Korea ; Leukocytes ; Liver ; Metabolism ; Pregnancy

Glucokinase is expressed only in both liver and pancreatic beta cells and has a key role in the regulation of glucose metabolism in these tissues. A number of gene defects associated with glucokinase gene and the cause of non-insulin-dependent diabetes mellitus are known, and the defects along the -30bp promoter site in particular are thought to be related to diabetes and glucose intolerance. To research on gene study related to diabetes, we looked into the relationship between the variation at -30bp of pancreatic beta cell specific glucokinase gene promoter and gestational diabetes mellitus(GDM) in Korea. METHODS: Forty patients with GDM and 62 normal controls were studied. Genomic DNA was extracted from peripheral leukocyte of patients with GDM and normal controls. The nucleotide variation at -30 bp of pancreatic beta cell specific glucokinase gene promoter was analyzed by PCR-SSCP methods. The sequences of amplified DNA were confirmed with direct sequencing method. The clinical features and the response of insulin secretion to oral glucose were analyzed between patients with GDM according to genotypes. RESULTS: Allelic frequency of position -30 bp of pancreatic beta cell specific glucokinase gene promoter did not differ between patients with GDM and normal subjects. However the frequency of G/A and A/A genotypes seemed to show a higher tendency in patients with GDM compare to the normal subjects. Clinical features, insulin response to oral glucose did not differ according to the type of variation at -30bp of pancreatic beta cell specific glucokinase gene promoter. CONCLUSION: These data suggested that the variation at -30 bp of pancreatic beta cell specific glucokinase gene promoter in patients with GDM are unlikely to be one of the possibilities of the genetic factors in the development of GDM. Therefore more sophisticated studies will be needed to elucidate the role of variation at -30bp of pancreatic beta cell specific glucokinase gene promoter in the insulin secretion to oral glucose.
Diabetes Mellitus, Type 2 ; Diabetes, Gestational* ; DNA ; Female ; Genotype ; Glucokinase* ; Glucose ; Glucose Intolerance ; Humans ; Insulin ; Insulin-Secreting Cells ; Korea ; Leukocytes ; Liver ; Metabolism ; Pregnancy