BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate ...BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion. METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls. Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry. SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence. RESULTS:Insulinoma patients presented the typical demons-trations of Whipple’s triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients. Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets. CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1. In contrast,MRP1,which is down-regulated in insulinomas, might reflect a negative feedback in insulin secretion.展开更多
BACKGROUND Transient neonatal diabetes mellitus(TNDM)is a rare form of diabetes mellitus that usually presents within the first 6 mo of life.Patients often enter remission within several months,although relapse can oc...BACKGROUND Transient neonatal diabetes mellitus(TNDM)is a rare form of diabetes mellitus that usually presents within the first 6 mo of life.Patients often enter remission within several months,although relapse can occur later in life.Mutations in the ABCC8 gene,which encodes the sulfonylurea receptor 1 of the ATP-sensitive potassium channel in pancreatic beta cells,are associated with TNDM and permanent neonatal diabetes.This study describes a novel de novo c.3880C>T heterozygous ABCC8 variant that causes TNDM and can be treated with sulfonylurea therapy.CASE SUMMARY We retrospectively analyzed 2 Chinese patients with TNDM who were diagnosed,treated,or referred for follow-up between September 2017 and September 2023.The patients were tested for mutations using targeted next-generation sequencing.Patients with neonatal diabetes mellitus caused by a c.3880C>T heterozygous missense variant in the ABCC8 gene have not been reported before.Both children had an onset of post-infectious diabetic ketoacidosis,which is worth noting.At a follow-up visit after discontinuing insulin injection,oral glyburide was found to be effective with no adverse reactions.CONCLUSION Early genetic testing of neonatal diabetes mellitus aids in accurate diagnosis and treatment and helps avoid daily insulin injections that may cause pain.展开更多
文摘BACKGROUND:Sulfonylurea receptor 1(SUR1)and multidrug resistance protein 1(MRP1)are two prominent members of multidrug resistance proteins associated with insulin secretion. The aims of this study were to investigate their expression in insulinomas and their sole and synergistic effects in modulating abnormal insulin secretion. METHODS:Fasting glucose,insulin and C-peptide were measured in 11 insulinoma patients and 11 healthy controls. Prolonged oral glucose tolerance tests were performed in 6 insulinoma patients.Insulin content,SUR1 and MRP1 were detected in 11 insulinoma patients by immunohistochemistry. SUR1 and MRP1 were also detected in 6 insulinoma patients by immunofluorescence. RESULTS:Insulinoma patients presented the typical demons-trations of Whipple’s triad.Fasting glucose of each insulinoma patient was lower than 2.8 mmol/L,and simultaneous insulin and C-peptide were increased in insulinoma patients. Prolonged oral glucose tolerance tests showed that insulin secretion in insulinoma patients were also stimulated by high glucose.Immunohistochemistry and immunofluorescence staining showed that SUR1 increased,but MRP1 decreased in insulinoma compared with the adjacent islets. CONCLUSIONS:The hypersecretion of insulin in insulinomas might be,at least partially,due to the enrichment of SUR1. In contrast,MRP1,which is down-regulated in insulinomas, might reflect a negative feedback in insulin secretion.
基金Supported by the Department of Science and Technology of Henan Province,China,No.222102310461。
文摘BACKGROUND Transient neonatal diabetes mellitus(TNDM)is a rare form of diabetes mellitus that usually presents within the first 6 mo of life.Patients often enter remission within several months,although relapse can occur later in life.Mutations in the ABCC8 gene,which encodes the sulfonylurea receptor 1 of the ATP-sensitive potassium channel in pancreatic beta cells,are associated with TNDM and permanent neonatal diabetes.This study describes a novel de novo c.3880C>T heterozygous ABCC8 variant that causes TNDM and can be treated with sulfonylurea therapy.CASE SUMMARY We retrospectively analyzed 2 Chinese patients with TNDM who were diagnosed,treated,or referred for follow-up between September 2017 and September 2023.The patients were tested for mutations using targeted next-generation sequencing.Patients with neonatal diabetes mellitus caused by a c.3880C>T heterozygous missense variant in the ABCC8 gene have not been reported before.Both children had an onset of post-infectious diabetic ketoacidosis,which is worth noting.At a follow-up visit after discontinuing insulin injection,oral glyburide was found to be effective with no adverse reactions.CONCLUSION Early genetic testing of neonatal diabetes mellitus aids in accurate diagnosis and treatment and helps avoid daily insulin injections that may cause pain.
