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

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

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

PURPOSE: Previous studies have shown that treatment with Smilax china L. leaf extract (SCLE) produces antidiabetic effects due to alpha-glucosidase inhibition. In this study, we examined the mechanism underlying these antidiabetic effects by examining glucose uptake in HepG2 cells cultured with SCLE. METHODS: Glucose uptake and glucokinase activity were examined using an assay kit. Expression of glucose transporter (GLUT)-2, GLUT-4, and HNF-1alpha was measured by RT-PCR or western blot. RESULTS: Treatment with SCLE resulted in enhanced glucose uptake in HepG2 cells, and this effect was especially pronounced when cells were cultured in an insulin-free medium. SCLE induced an increase in expression of GLUT-2 but not GLUT-4. The increase in the levels of HNF-1alpha, a GLUT-2 transcription factor, in total protein extract and nuclear fraction suggest that the effects of SCLE may occur at the level of GLUT-2 transcription. In addition, by measuring the change in glucokinase activity following SCLE treatment, we confirmed that SCLE stimulates glucose utilization by direct activation of this enzyme. CONCLUSION: These results demonstrate that the potential antidiabetic activity of SCLE is due at least in part to stimulation of glucose uptake and an increase in glucokinase activity, and that SCLE-stimulated glucose uptake is mediated through enhancement of GLUT-2 expression by inducing expression of its transcription factor, HNF-1alpha.
Absorption* ; alpha-Glucosidases ; Blotting, Western ; China* ; Glucokinase ; Glucose Transport Proteins, Facilitative ; Glucose* ; Hep G2 Cells* ; Hepatocyte Nuclear Factor 1-alpha ; Smilax* ; Transcription Factors

BACKGROUND/OBJECTIVES: The goal of this study was to examine the effect of Sargassum coreanum extract (SCE) on blood glucose concentration and insulin resistance in C57BL-KsJ-db/db mice. MATERIALS/METHODS: For 6 weeks, male C57BL/KsJ-db/db mice were administrated SCE (0.5%, w/w), and rosiglitazone (0.005%, w/w). RESULTS: A supplement of the SCE for 6 weeks induced a significant reduction in blood glucose and glycosylated hemoglobin concentrations, and it improved hyperinsulinemia compared to the diabetic control db/db mice. The glucokinase activity in the hepatic glucose metabolism increased in the SCE-supplemented db/db mice, while phosphoenolpyruvate carboxykinase and glucose-6-phosphatase activities in the SCE-supplemented db/db mice were significantly lower than those in the diabetic control db/db mice. The homeostatic index of insulin resistance was lower in the SCE-supplemented db/db mice than in the diabetic control db/db mice. CONCLUSIONS: These results suggest that a supplement of the SCE lowers the blood glucose concentration by altering the hepatic glucose metabolic enzyme activities and improves insulin resistance.
Animals ; Blood Glucose ; Glucokinase ; Glucose ; Glucose-6-Phosphatase ; Hemoglobin A, Glycosylated ; Humans ; Hyperglycemia* ; Hyperinsulinism ; Insulin Resistance* ; Insulin* ; Male ; Metabolism ; Mice* ; Phosphoenolpyruvate ; Sargassum*

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

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