This study aims to investigate the impact of hepatocyte nuclear factor 1β (HNF1b) on macrophage sortilin-mediated lipid metabolism and aortic atherosclerosis and explore the role of the flavone of Polygonatum odoratum (PAOA-flavone)-promoted small ubiquitin-related modifier (SUMO) modification in the atheroprotective efficacy of HNF1b. HNF1b was predicted to be a transcriptional regulator of sortilin expression via bioinformatics, dual-luciferase reporter gene assay, and chromatin immunoprecipitation. HNF1b overexpression decreased sortilin expression and cellular lipid contents in THP-1 macrophages, leading to a depression in atherosclerotic plaque formation in low-density lipoprotein (LDL) receptor-deficient (LDLR^-/-) mice. Multiple SUMO1-modified sites were identified on the HNF1b protein and co-immunoprecipitation confirmed its SUMO1 modification. The SUMOylation of HNF1b protein enhanced the HNF1b-inhibited effect on sortilin expression and reduced lipid contents in macrophages. PAOA-flavone treatment promoted SUMO-activating enzyme subunit 1 (SAE1) expression and SAE1-catalyzed SUMOylation of the HNF1b protein, which prevented sortilin-mediated lipid accumulation in macrophages and the formation of atherosclerotic plaques in apolipoprotein E-deficient (ApoE^-/-) mice. Interference with SAE1 abrogated the improvement in lipid metabolism in macrophage cells and atheroprotective efficacy in vivo upon PAOA-flavone administration. In summary, HNF1b transcriptionally suppressed sortilin expression and macrophage lipid accumulation to inhibit aortic lipid deposition and the development of atherosclerosis. This anti-atherosclerotic effect was enhanced by PAOA-flavone-facilitated, SAE1-catalyzed SUMOylation of the HNF1b protein.
Mice ; Animals ; Polygonatum/metabolism* ; Sumoylation ; Hepatocyte Nuclear Factor 1-beta/metabolism* ; Atherosclerosis/metabolism* ; Flavones ; Lipids

OBJECTIVEThere is a paucity of published works that systematically evaluate gene anomalies or clinical features of patients with renal cysts and diabetes syndrome (RCAD)/maturity onset diabetes of the young type 5 (MODY5). The purpose of this review was to systematically assess the detection rate, genetic and phenotypic implications of heterozygous autosomal dominant TCF2 anomalies.

DATA SOURCESMEDLINE database was searched to select articles recorded in English from 1997 to 2008. The focus was monoallelic germline TCF2 gene mutations/deletions. Biallelic inactivation, polymorphisms, DNA modification (hypomethylation and hypermethylation), loci associated with cancer risk, and somatic TCF2 anomalies were all excluded.

STUDY SELECTIONAfter searching the literature, 50 articles were selected.

RESULTSThe detection rate of TCF2 anomalies was 9.7% and varied considerably among MODY (1.4%), renal structure anomalies (RSA) (21.4%) and RSA with MODY (41.2%) subgroups. Mutations were strikingly located within the DNA binding domain and varied among exons of the DNA binding domain: exons 2 and 4 were the hottest spots, while mutations were sporadically distributed in exon 3. The consistent phenotypes were RSA (89.6%) and diabetes mellitus (DM) (45.0%). However, the concurrence of RSA and DM was relatively low (27.5%), which hinders the optimal performance of genetic testing and obtainment of timely diagnosis. Other organ involvements were complementary and necessary for the early identification of patients with TCF2 anomalies. Analysis of phenotypes of TCF2 point mutations showed significant differences in the detection rates of RSA, impaired renal function (IRF) and DM according to mutation type but not mutation location.

CONCLUSIONThese valuable features of TCF2 anomalies that previously did not receive sufficient attention should not be neglected.

Central Nervous System Diseases ; metabolism ; Dental Enamel ; abnormalities ; metabolism ; Diabetes Mellitus ; metabolism ; Diabetes Mellitus, Type 2 ; metabolism ; Hepatocyte Nuclear Factor 1-beta ; metabolism ; Humans ; Kidney Diseases, Cystic ; metabolism

OBJECTIVETo study the expressions of β-catenin in hepatocellular carcinoma (HCC) tissue, adjacent cirrhotic liver tissue and hemangioma-surrounding liver tissue to understand whether their difference in expression will influence on the prognosis and to study the relationship between Wnt/β-catenin signaling pathway and HNF-1α expression.

METHODS50 specimens of HCC, 50 specimens of adjacent cirrhotic liver tissue and 7 specimens of hemangioma-surrounding liver tissue were used to detect the differences in the expression of β-catenin and HNF-1α in them by immunohistochemistry.

RESULTSThe expression rate of &beta;-catenin was 74.0% (37/50) in the HCC tissue, 18.0% (9/50) in cirrhotic liver tissue, and 14.3% (1/7) in hemangioma-surrounding liver tissue. The expression rate of &beta;-catenin in HCC tissue was significantly higher than that in the hemangioma-surrounding liver tissue (P = 0.002) and cirrhotic liver tissue (P < 0.001). The patients with abnormal expression had worse prognosis. Among the 50 HCC cases, the expression of HNF-1α was negative in 20.0% (10/50), weak positive in 40.0% (20/50), moderately positive in 26.0% (13/50), and strong positive in 14.0% (7/50). Among the 50 adjacent cirrhotic liver tissues, the expression of HNF-1α was negative in 12.0% (6/50), weak positive in 20.0% (10/50), moderately positive in 52.0% (26/50) and strong positive in 16.0% (8/50). In the 7 cases of hemangioma-surrounding liver tissue, the expression of HNF-1α was negative in 0(0/7), weak positive in 14.3% (1/7), moderately positive in 28.6% (2/7) and strong positive in 57.1% (4/7). The positive expression rate of HNF-1α in the HCC tissue was significantly lower than that in the hemangioma-surrounding liver tissues (P = 0.029) and adjacent cirrhotic liver tissues (P = 0.008). The patients with positive HNF-1α expression had a better prognosis. The abnormal expression of &beta;-catenin was negatively correlated with positive HNF-1α expression (r = -0.673, P < 0.001).

CONCLUSIONSThe occurrence and development of HCC is related to the abnormal &beta;-catenin expression. There is a negative correlation between Wnt/&beta;-catenin signaling pathway and HNF-1α expression.

Carcinoma, Hepatocellular ; diagnosis ; metabolism ; Hemangioma ; Hepatocyte Nuclear Factor 1-alpha ; genetics ; metabolism ; Humans ; Immunohistochemistry ; Liver Neoplasms ; diagnosis ; metabolism ; Prognosis ; beta Catenin ; genetics ; metabolism

Owing to the progress of imaging techniques, benign hepatocellular nodules are increasingly discovered in the clinical practice. This group of lesions mostly arises in the context of a putatively normal healthy liver and includes either pseudotumoral and tumoral nodules. Focal nodular hyperplasia and hepatocellular adenoma are prototypical examples of these two categories of nodules. In this review we aim to report the main pathological criteria of differential diagnosis between focal nodular hyperplasia and hepatocellular adenoma, which mainly rests upon morphological and phenotypical features. We also emphasize that for a correct diagnosis the clinical context such as sex, age, assumption of oral contraceptives, associated metabolic or vascular disturbances is of paramount importance. While focal nodular hyperplasia is a single entity epidemiologically more frequent than adenoma, the latter is representative of a more heterogeneous group which has been recently and extensively characterized from a clinical, morphological, phenotypical and molecular profile. The use of the liver biopsy in addition to imaging and the clinical context are important diagnostic tools of these lesions. In this review we will survey their systematic pathobiology and propose a diagnostic algorithm helpful to increase the diagnostic accuracy of not dedicated liver pathologists. The differential diagnosis between so-called typical and atypical adenoma and well differentiated hepatocellular carcinoma will also be discussed.
Adenoma/*diagnosis/surgery ; Carcinoma, Hepatocellular/diagnosis ; Diagnosis, Differential ; Focal Nodular Hyperplasia/*diagnosis/surgery ; Hepatocyte Nuclear Factor 1-alpha/metabolism ; Humans ; Liver/pathology ; Liver Neoplasms/*diagnosis/surgery ; beta Catenin/genetics/metabolism

Owing to the progress of imaging techniques, benign hepatocellular nodules are increasingly discovered in the clinical practice. This group of lesions mostly arises in the context of a putatively normal healthy liver and includes either pseudotumoral and tumoral nodules. Focal nodular hyperplasia and hepatocellular adenoma are prototypical examples of these two categories of nodules. In this review we aim to report the main pathological criteria of differential diagnosis between focal nodular hyperplasia and hepatocellular adenoma, which mainly rests upon morphological and phenotypical features. We also emphasize that for a correct diagnosis the clinical context such as sex, age, assumption of oral contraceptives, associated metabolic or vascular disturbances is of paramount importance. While focal nodular hyperplasia is a single entity epidemiologically more frequent than adenoma, the latter is representative of a more heterogeneous group which has been recently and extensively characterized from a clinical, morphological, phenotypical and molecular profile. The use of the liver biopsy in addition to imaging and the clinical context are important diagnostic tools of these lesions. In this review we will survey their systematic pathobiology and propose a diagnostic algorithm helpful to increase the diagnostic accuracy of not dedicated liver pathologists. The differential diagnosis between so-called typical and atypical adenoma and well differentiated hepatocellular carcinoma will also be discussed.
Adenoma/*diagnosis/surgery ; Carcinoma, Hepatocellular/diagnosis ; Diagnosis, Differential ; Focal Nodular Hyperplasia/*diagnosis/surgery ; Hepatocyte Nuclear Factor 1-alpha/metabolism ; Humans ; Liver/pathology ; Liver Neoplasms/*diagnosis/surgery ; beta Catenin/genetics/metabolism

Mutation in HNF1B, the hepatocyte nuclear factor-1beta (HNF-1beta) gene, results in maturity-onset diabetes of the young (MODY) 5, which is characterized by gradual impairment of insulin secretion. However, the functional role of HNF-1beta in insulin secretion and glucose metabolism is not fully understood. We identified a family with early-onset diabetes that fulfilled the criteria of MODY. Sanger sequencing revealed that a heterozygous P159L (CCT to CTT in codon 159 in the DNA-binding domain) mutation in HNF1B was segregated according to the affected status. To investigate the functional consequences of this HNF1B mutation, we generated a P159L HNF1B construct. The wild-type and mutant HNF1B constructs were transfected into COS-7 cells in the presence of the promoter sequence of human glucose transporter type 2 (GLUT2). The luciferase reporter assay revealed that P159L HNF1B had decreased transcriptional activity compared to wild-type (p < 0.05). Electrophoretic mobility shift assay showed reduced DNA binding activity of P159L HNF1B. In the MIN6 pancreatic beta-cell line, overexpression of the P159L mutant was significantly associated with decreased mRNA levels of GLUT2 compared to wild-type (p < 0.05). However, INS expression was not different between the wild-type and mutant HNF1B constructs. These findings suggests that the impaired insulin secretion in this family with the P159L HNF1B mutation may be related to altered GLUT2 expression in beta-cells rather than decreased insulin gene expression. In conclusion, we have identified a Korean family with an HNF1B mutation and characterized its effect on the pathogenesis of diabetes.
Animals ; Codon ; COS Cells ; Diabetes Mellitus, Type 2* ; DNA ; Electrophoretic Mobility Shift Assay ; Gene Expression ; Glucose ; Glucose Transporter Type 2 ; Hepatocyte Nuclear Factor 1-beta ; Humans ; Insulin ; Luciferases ; Metabolism ; Point Mutation ; RNA, Messenger