36 research outputs found
An Atypical Case of Late-Onset Wolfram Syndrome 1 without Diabetes Insipidus.
Wolfram syndrome 1, a rare autosomal recessive neurodegenerative disease, is caused by mutations in the WFS1 gene. It is characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and deafness (DIDMOAD), and other clinical manifestations such as urological and neurological disorders. Here we described the case of a patient with an atypical late-onset Wolfram syndrome 1 without DI. Our WS1 patient was a c.1620_1622delGTG (p.Trp540del)/c.124 C > T (p.Arg42*) heterozygous compound. The p.Arg42* nonsense mutation was also found in heterozygosity in his sister and niece, both suffering from psychiatric disorders. The p.Arg42* nonsense mutation has never been found in WS1 and its pathogenicity is unclear so far. Our study underlined the need to study a greater number of WS1 cases in order to better understand the clinical significance of many WFS1 variants
Case Report: Beyond type 1 diabetes: a case of delayed MODY1 diagnosis and successful transition to sulfonylurea therapy
Maturity-onset diabetes of the young (MODY) is a rare, genetically heterogeneous form of diabetes characterized by early-onset dysglycaemia, typically before 25 years of age, and autosomal dominant inheritance. Among the different forms of MODY, HNF4A-MODY (MODY1) is caused by mutations in the HNF4A gene, which encodes a transcription factor essential for glucose metabolism. Here, we describe a novel splicing variant in the HNF4A gene (c.319+1G>A) identified in a 15-year-old girl with non-ketoacidotic diabetes and a family history of diabetes. Initially diagnosed with Type 1 diabetes (T1D), she required low insulin doses and displayed negative autoimmune markers. Genetic testing revealed the heterozygous variant inherited from her father and functional studies confirmed the variant's impact on splicing. Following the diagnosis of HNF4A-MODY, the patient's treatment was switched from insulin to sulfonylureas, resulting in improved glycaemic control and time in range, along with an improved quality of life. The report highlights the importance of considering MODY in young patients with diabetes who lack typical T1D characteristics and the value of combining clinical, genetic, and functional testing for accurate diagnosis and personalized treatment
A novel CISD2 intragenic deletion, optic neuropathy and platelet aggregation defect in Wolfram syndrome type 2
Wolfram Syndrome: New Mutations, Different Phenotype
BACKGROUND: Wolfram Syndrome (WS) is an autosomal recessive neurodegenerative disorder characterized by Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy, and Deafness identified by the acronym "DIDMOAD". The WS gene, WFS1, encodes a transmembrane protein called Wolframin, which recent evidence suggests may serve as a novel endoplasmic reticulum calcium channel in pancreatic β-cells and neurons. WS is a rare disease, with an estimated prevalence of 1/550.000 children, with a carrier frequency of 1/354. The aim of our study was to determine the genotype of WS patients in order to establish a genotype/phenotype correlation. METHODOLOGY/PRINCIPAL FINDINGS: We clinically evaluated 9 young patients from 9 unrelated families (6 males, 3 females). Basic criteria for WS clinical diagnosis were coexistence of insulin-treated diabetes mellitus and optic atrophy occurring before 15 years of age. Genetic analysis for WFS1 was performed by direct sequencing. Molecular sequencing revealed 5 heterozygous compound and 3 homozygous mutations. All of them were located in exon 8, except one in exon 4. In one proband only an heterozygous mutation (A684V) was found. Two new variants c.2663 C>A and c.1381 A>C were detected. CONCLUSIONS/SIGNIFICANCE: Our study increases the spectrum of WFS1 mutations with two novel variants. The male patient carrying the compound mutation [c.1060_1062delTTC]+[c.2663 C>A] showed the most severe phenotype: diabetes mellitus, optic atrophy (visual acuity 5/10), deafness with deep auditory bilaterally 8000 Hz, diabetes insipidus associated to reduced volume of posterior pituitary and pons. He died in bed at the age of 13 years. The other patient carrying the compound mutation [c.409_424dup16]+[c.1381 A>C] showed a less severe phenotype (DM, OA)
p38 MAPK and JNK Antagonistically Control Senescence and Cytoplasmic p16INK4A Expression in Doxorubicin-Treated Endothelial Progenitor Cells
Patients treated with low-dose anthracyclines often show late onset cardiotoxicity. Recent studies suggest that this form of cardiotoxicity is the result of a progenitor cell disease. In this study we demonstrate that Cord Blood Endothelial Progenitor Cells (EPCs) exposed to low, sub-apoptotic doses of doxorubicin show a senescence phenotype characterized by increased SA-b-gal activity, decreased TRF2 and chromosomal abnormalities, enlarged cell shape, and disarrangement of F-actin stress fibers accompanied by impaired migratory ability. P16 INK4A localizes in the cytoplasm of doxorubicin-induced senescent EPCs and not in the nucleus as is the case in EPCs rendered senescent by different stimuli. This localization together with the presence of an arrest in G2, and not at the G1 phase boundary, which is what usually occurs in response to the cell cycle regulatory activity of p16INK4A, suggests that doxorubicin-induced p16 INK4A does not regulate the cell cycle, even though its increase is closely associated with senescence. The effects of doxorubicin are the result of the activation of MAPKs p38 and JNK which act antagonistically. JNK attenuates the senescence, p16 INK4A expression and cytoskeleton remodeling that are induced by activated p38. We also found that conditioned medium from doxorubicin-induced senescent cardiomyocytes does not attract untreated EPCs, unlike conditioned medium from apoptotic cardiomyocytes which has a strong chemoattractant capacity. In conclusion, this study provides a better understanding of the senescence of doxorubicin-treated EPCs, which may be helpful in preventing and treating late onset cardiotoxicity
Mother and daughter carrying the same KCNJ11 mutation but with a different response to switching from insulin to sulfonylurea
A mild impairment of K+ATP channel function caused by two different ABCC8 defects in an Italian newborn
“Pesto” Mutation: Phenotypic and Genotypic Characteristics of Eight GCK/MODY Ligurian Patients
Maturity Onset Diabetes of the Young (MODY) is a monogenic form of diabetes mellitus (DM) that accounts for around 2–5% of all types of diabetes. Autosomal dominant inheritance in pathogenic variations of 14 genes related to β-cell functions can lead to monogenic types of diabetes. In Italy, GCK/MODY is the most frequent form and it is caused by mutations of the glucokinase (GCK). Patients with GCK/MODY usually have stable mild fasting hyperglycaemia with mildly elevated HbA1c levels and rarely need pharmacological treatment. Molecular analysis of the GCK coding exons was carried out by Sanger sequencing in eight Italian patients. All the probands were found to be heterozygous carriers of a pathogenic gross insertion/deletion c.1279_1358delinsTTACA; p.Ser426_Ala454delinsLeuGln. It was previously described for the first time by our group in a large cohort of Italian GCK/MODY patients. The higher levels of HbA1c (6.57% vs. 6.1%), and the higher percentage of patients requiring insulin therapy (25% vs. 2%) compared to the previously studied Italian patients with GCK/MODY, suggest that the mutation discovered could be responsible for a clinically worse form of GCK/MODY. Moreover, as all the patients carrying this variant share an origin from the same geographic area (Liguria), we postulate a possible founder effect and we propose to name it the “pesto” mutation.</jats:p
