OBJECTIVE: To explore the clinical characteristics and molecular basis for children and adolescents with monogenic diabetes.
METHODS: A retrospective analysis was carried out for the clinical manifestations and laboratory data of 116 children and adolescents diagnosed with diabetes at Ningbo Women and Children\'s Hospital from January 2020 to March 2023. Whole exome sequencing and mitochondrial gene sequencing were carried out on 21 children with suspected monogenic diabetes.
RESULTS: A total of 10 cases of monogenic diabetes were diagnosed, all of which were Maturity-onset Diabetes Of the Young (MODY). Six cases of MODY2 were due to GCK gene mutations, 1 case of MODY3 was due to HNF1A gene mutation, 2 cases of MODY12 were due to ABCC8 gene mutations, and 1 case of MODY13 was due to KCNJ11 gene mutation. Nine of the 10 patients with MODY had no typical symptoms of diabetes. A family history of diabetes was significantly more common in the MODY group compared with the T1DM and T2DM groups (P < 0.05). The BMI of the MODY group was higher than that of the T1DM group (P < 0.05). The initial blood glucose level was lower than that of the T1DM group (P < 0.05), and there was no significant difference compared with the T2DM group. The fasting C-peptide level of the MODY group was higher than that of the T1DM group (P < 0.05), and there was no significant difference compared with the T2DM group. Glycosylated hemoglobin of the MODY group was lower than both the T1DM and T2DM groups (P < 0.05).
CONCLUSIONS: In this study, MODY has accounted for the majority of monogenic diabetes among children and adolescents, and the common mutations were those of the GCK gene in association with MODY2. Blood glucose and glycosylated hemoglobin of children with MODY were slightly increased, whilst the islet cell function had remained, and the clinical manifestations and laboratory tests had overlapped with those of type 2 diabetes. WES and mitochondrial gene sequencing can clarify the etiology of monogenic diabetes and facilitate precise treatment.

Maturity Onset Diabetes of the Young (MODY) is a young-onset, monogenic form of diabetes without needing insulin treatment. Diagnostic testing is expensive. To aid decisions on who to test, we aimed to develop a MODY probability calculator for paediatric cases at the time of diabetes diagnosis, when the existing \"MODY calculator\" cannot be used. Firth logistic regression models were developed on data from 3541 paediatric patients from the Swedish \'Better Diabetes Diagnosis\' (BDD) population study (n = 46 (1.3%) MODY (HNF1A, HNF4A, GCK)). Model performance was compared to using islet autoantibody testing. HbA1c, parent with diabetes, and absence of polyuria were significant independent predictors of MODY. The model showed excellent discrimination (c-statistic = 0.963) and calibrated well (Brier score = 0.01). MODY probability > 1.3% (ie. above background prevalence) had similar performance to being negative for all 3 antibodies (positive predictive value (PPV) = 10% v 11% respectively i.e. ~ 1 in 10 positive test rate). Probability > 1.3% and negative for 3 islet autoantibodies narrowed down to 4% of the cohort, and detected 96% of MODY cases (PPV = 31%). This MODY calculator for paediatric patients at time of diabetes diagnosis will help target genetic testing to those most likely to benefit, to get the right diagnosis.

Maturity-onset diabetes of the young type 2 (MODY2) is an autosomal dominant disorder caused by mutations in the GCK gene. It is characterized by a non-progressive slight increase in glycosylated hemoglobin (HbA1c), and mildly raised fasting glucose. Here, we generated an induced pluripotent stem cell line SDQLCHi063-A from a five-year-old boy with MODY2 carrying exon 1 deletion of the GCK gene (OMIM*138079). The iPSC line carries original gene mutation, expresses pluripotency markers, has normal karyotype and differentiated spontaneously in the three germ layers.

The leaves of Ficus johannis Boiss (F. johannis), commonly known as Fig tree, Anjir, and Teen, are used by the folk medicinal practitioners in Iran for controlling hyperglycemia in diabetic patients. This study investigated the pharmacological basis for antidiabetic effect of the ethanolic extract of F. johannis leaves using in vitro and in vivo experimental models. Qualitative screening of phytochemicals, estimation of total phenolic and flavonoid contents, and in vitro antioxidant and α-amylase inhibition assays were performed. Moreover, the High-performance liquid chromatography (HPLC) quantification, acute toxicity, glucose tolerance, and in vivo antidiabetic effect along with the evaluation of gene expressions involved in diabetes mellitus were carried out. Significant quantities of phenolic (71.208 ± 2.89 mgg-1 GAE) and flavonoid (26.38 ± 3.53 mgg-1 QE) were present. Inhibitory concentration (IC50) of the plant extract exhibited an excellent in vitro antioxidant (IC50 = 33.81 µg/mL) and α-amylase (IC50 = 12.18 µg/mL) inhibitory potential. The HPLC analysis confirmed the gallic acid (257.79 mgg-1) as main constituent of the extract followed by kaempferol (22.86 mgg-1), myricetin (0.16 mgg-1), and quercetin (3.22 mgg-1). Ethanolic extract displayed glucose tolerance in normo-glycemic rats. Streptozotocin-induced hyperglycemia declined dose dependently in the extract treated rats with improvement in lipid profile and liver and renal function biomarkers. The F. johannis-treated groups showed an increase in mRNA expressions of glucose transporter 4 (GLUT-4), glucokinase, insulin growth like factor 1 and peroxisomal proliferator activating receptor gamma in pancreas. However, the Glucose-6-phosphatase was downregulated. Present study suggests that the ethanolic extract of F. johannis leaves demonstrates a good anti-diabetic profile by improving insulin sensitivity, GLUT-4 translocation, and carbohydrate metabolism while inhibiting lipogenesis.

The Germinal Center Kinase III (GckIII) pathway is a Hippo-like kinase module defined by sequential activation of Ste20 kinases Thousand and One (Tao) and GckIII, followed by nuclear dbf2-related (NDR) kinase Tricornered (Trc). We previously uncovered a role for the GckIII pathway in Drosophila melanogaster tracheal (respiratory) tube morphology. The trachea form a network of branched epithelial tubes essential for oxygen transport, and are structurally analogous to branched tubular organs in vertebrates, such as the vascular system. In the absence of GckIII pathway function, aberrant dilations form in tracheal tubes characterized by mislocalized junctional and apical proteins, suggesting that the pathway is important in maintaining tube integrity in development. Here, we observed a genetic interaction between trc and Cerebral cavernous malformations 3 (Ccm3), the Drosophila ortholog of a human vascular disease gene, supporting our hypothesis that the GckIII pathway functions downstream of Ccm3 in trachea, and potentially in the vertebrate cerebral vasculature. However, how GckIII pathway signaling is regulated and the mechanisms that underpin its function in tracheal development are unknown. We undertook biochemical and genetic approaches to identify proteins that interact with Trc, the most downstream GckIII pathway kinase. We found that known GckIII and NDR scaffold proteins are likely to control GckIII pathway signaling in tracheal development, consistent with their conserved roles in Hippo-like modules. Furthermore, we show genetic interactions between trc and multiple enzymes in glycolysis and oxidative phosphorylation, suggesting a potential function of the GckIII pathway in integrating cellular energy requirements with maintenance of tube integrity.

UNASSIGNED: Congenital hyperinsulinism (HI) is the most common cause of persistent hypoglycemia in children. In addition to typical focal or diffuse HI, some cases with diazoxide-unresponsive congenital HI have atypical pancreatic histology termed Localized Islet Nuclear Enlargement (LINE) or mosaic HI, characterized by histologic features similar to diffuse HI, but confined to only a region of pancreas. Our objective was to characterize the phenotype and genotype of children with LINE-HI.
UNASSIGNED: The phenotype and genotype features of 12 children with pancreatic histology consistent with LINE-HI were examined.
UNASSIGNED: We compiled clinical features of 12 children with LINE-HI and performed next-generation sequencing on specimens of pancreas from eight of these children to look for mosaic mutations in genes known to be associated with diazoxide-unresponsive HI (ABCC8, KCNJ11, and GCK).
UNASSIGNED: Children with LINE-HI had lower birth weights and later ages of presentation compared to children with typical focal or diffuse HI. Partial pancreatectomy in LINE-HI cases resulted in euglycemia in 75% of cases; no cases have developed diabetes. Low-level mosaic mutations were identified in the pancreas of six cases with LINE-HI (three in ABCC8, three in GCK). Expression studies confirmed that all novel mutations were pathogenic.
UNASSIGNED: These results indicate that post-zygotic low-level mosaic mutations of known HI genes are responsible for some cases of LINE-HI that lack an identifiable germ-line mutation and that partial pancreatectomy may be curative for these cases.

Nonalcoholic fatty liver disease (NAFLD) is defined by excessive accumulation of lipid droplets within hepatocytes. The STE20-type kinases comprising the germinal center kinase III (GCKIII) subfamily - MST3, MST4, and STK25 - decorate intrahepatocellular lipid droplets and have recently emerged as critical regulators of the initiation and progression of NAFLD. While significant advancement has been made toward deciphering the role of GCKIII kinases in hepatic fat accumulation (i.e., steatosis) as well as the aggravation of NAFLD into its severe form nonalcoholic steatohepatitis (NASH), much remains to be resolved. This review provides a brief overview of the recent studies in patient cohorts, cultured human cells, and mouse models, which have characterized the function of MST3, MST4, and STK25 in the regulation of hepatic lipid accretion, meta-inflammation, and associated cell damage in the context of NAFLD/NASH. We also highlight the conflicting data and emphasize future research directions that are needed to advance our understanding of GCKIII kinases as potential targets in the therapy of NAFLD and its comorbidities. Conclusions: Several lines of evidence suggest that GCKIII proteins govern the susceptibility to hepatic lipotoxicity and that pharmacological inhibition of these kinases could mitigate NAFLD development and aggravation. Comprehensive characterization of the molecular mode-of-action of MST3, MST4, and STK25 in hepatocytes as well as extrahepatic tissues is important, especially in relation to their impact on carcinogenesis, to fully understand the efficacy as well as safety of GCKIII antagonism.

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by persistent hyperglycemia and is associated with serious complications. The risk factors for T2DM include both genetic and lifestyle factors. Genome‑wide association studies have indicated the association of genetic variations with many diseases, including T2DM. Glucokinase (GCK) plays a key role in the regulation of insulin release in the pancreas and catalyzes the first step in glycolysis in the liver. Genetic alterations in the GCK gene have been implicated in both hyperglycemia and hypoglycemia. MicroRNAs (miRNAs/miRs) are small non‑coding RNA molecules that are involved in the important physiological processes including glucose metabolism. In the present study, the association of the single nucleotide polymorphisms (SNPs) in the GCK, MIR‑196A‑2 and MIR‑423 genes with susceptibility to T2DM in patients from two regions of Saudi Arabia were examined, using the tetra‑primer amplification refractory mutation system. The results showed that the AA genotype and the A allele of GCK rs1799884 were associated with T2DM [odds ratio (OR)=2.25, P=0.032 and OR=1.55, P=0.021, respectively]. Likewise, the CT genotype and T allele of MIR‑196A‑2 rs11614913 were associated with an increased risk of T2DM (OR=2.36, P=0.0059 and OR=1.74, P=0.023, respectively). In addition, the CA genotype of MIR‑423 rs6505162 C>A was found to be linked with T2DM (OR=2.12 and P=0.021). It was concluded in the present research study that gene variations in GCK, MIR‑196A‑2 and MIR‑423 are potentially associated with an increased risk of T2DM. These results, in the future, may help in the identification and stratification of individuals susceptible to T2DM. Future longitudinal studies with larger sample sizes and in different ethnic populations are recommended to validate these findings.

Cavernous cerebral malformations can arise because of mutations in the CCM1, CCM2, or CCM3 genes, and lack of Cdc42 has also been reported to induce these malformations in mice. However, the role of the CCM3 (cerebral cavernous malformation 3)-associated kinases in cavernoma development is not known, and we, therefore, have investigated their role in the process.
We used a combination of an in vivo approach, using mice genetically modified to be deficient in the CCM3-associated kinases STK24 and STK25 (serine/threonine kinases 24 and 25), and the in vitro model of human endothelial cells in which expression of STK24 and STK25 was inhibited by RNA interference.
Mice deficient for both Stk24 and Stk25, but not for either of them individually, developed aggressive vascular lesions with the characteristics of cavernomas at an early age. Stk25 deficiency also gave rise to vascular anomalies in the context of Stk24 heterozygosity. Human endothelial cells deficient for both kinases phenocopied several of the consequences of CCM3 loss, and single STK25 deficiency also induced KLF2 expression, Golgi dispersion, altered distribution of β-catenin, and appearance of stress fibers.
The CCM3-associated kinases STK24 and STK25 play a major role in the inhibition of cavernoma development.

OBJECTIVE: To investigate the frequency and spectrum of glucokinase (GCK) mutations in a cohort of adults from an island population having a high prevalence of diabetes mellitus (DM).
METHODS: A single-centre cohort study was conducted, including 145 non-obese adults of Maltese-Caucasian ethnicity with impaired fasting glycaemia (IFG) or non-autoimmune diabetes diagnosed before the age of 40 years. Bidirectional sequencing of the GCK coding regions was performed. Genotype-phenotype associations and familial segregation were explored and the effects of missense variants on protein structure were evaluated using computational analysis.
RESULTS: Three probands with pathogenic/likely pathogenic GCK variants in the heterozygous state having clinical features consistent with GCK-diabetes were detected. The missense variants have structurally destabilising effects on protein structure. GCK variant carriers exhibited a significantly lower body mass index and serum triglyceride levels when compared to GCK variant non-carriers.
CONCLUSIONS: The frequency of GCK-diabetes is approximately 2% in non-obese Maltese adults with diabetes or prediabetes. This study broadens the mutational spectrum of GCK and highlights clinical features that could be useful in discriminating GCK-DM from type 2 DM or prediabetes. It reinforces the need for increased molecular testing in young adults with diabetes having a suspected monogenic aetiology.