ABSTRACT
AIMS: Combined magnetic resonance imaging (MRI) of molecular and morpho-functional changes might prove highly valuable for the elucidation of pathological processes involved in the development of cardiac diseases. Our aim was to test a novel MRI reporter gene for in vivo assessment of the canonical Wnt/ß-catenin/TCF pathway activation, an important regulator of post-ischaemic cardiac remodelling. METHODS AND RESULTS: We designed and developed a chimeric construct encoding for both of iron-binding human ferritin heavy chain (hFTH) controlled by the ß-catenin-responsive TCF/lymphoid-enhancer binding factor (Lef) promoter and constitutively expressed green fluorescent protein (GFP). It was carried by adeno-associated virus serotype 9 (rAAV9) vectors and delivered to the peri-infarct myocardium of rats subjected to coronary ligation (n = 11). By 1.5 T MRI and a multiecho T2* gradient echo sequence, we detected iron accumulation only in the border zone of the transduced infarcted hearts. In the same cardiac area, post-mortem histological analysis confirmed the co-existence of iron accumulation and GFP. The iron signal was absent when rats (n = 6) were chronically treated with SEN195 (10 mg/kg/day), a small-molecular inhibitor of ß-catenin/TCF-dependent gene transcription. Canonical Wnt pathway inhibition attenuated the post-ischaemic remodelling process, as demonstrated by the significant preservation of cardiac function, the 42 ± 1% increase of peri-infarct arteriolar density and 43 ± 3% reduction in infarct scar size compared with untreated animals. CONCLUSIONS: The TCF/Lef promoter-hFTH construct is a novel and reliable MRI reporter gene for in vivo detection of the canonical Wnt/ß-catenin/TCF activation state in response to cardiac injury and therapeutic interventions.
Subject(s)
Genes, Reporter , Magnetic Resonance Imaging, Cine/methods , Molecular Imaging/methods , Myocardial Infarction/diagnostic imaging , Myocardium/metabolism , TCF Transcription Factors/metabolism , Ventricular Function, Left , Ventricular Remodeling , Wnt Signaling Pathway , Animals , Apoferritins/biosynthesis , Apoferritins/genetics , Dependovirus/genetics , Disease Models, Animal , Genetic Vectors , Green Fluorescent Proteins/biosynthesis , Green Fluorescent Proteins/genetics , HEK293 Cells , Humans , Iron/metabolism , Male , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Myocardium/pathology , Predictive Value of Tests , Promoter Regions, Genetic , Rats, Wistar , Reproducibility of Results , TCF Transcription Factors/genetics , TransfectionABSTRACT
A series of amides bearing a variety of amidine head groups was investigated as BACE1 inhibitors with respect to inhibitory activity in a BACE1 enzyme as well as a cell-based assay. Determination of their basicity as well as their properties as substrates of P-glycoprotein revealed that a 2-amino-1,3-oxazine head group would be a suitable starting point for further development of brain penetrating compounds for potential Alzheimer's disease treatment.
Subject(s)
Amides/chemistry , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Aspartic Acid Endopeptidases/antagonists & inhibitors , Protease Inhibitors/chemistry , Alzheimer Disease/drug therapy , Amides/metabolism , Amides/therapeutic use , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/metabolism , Binding Sites , Humans , Molecular Docking Simulation , Protease Inhibitors/metabolism , Protease Inhibitors/therapeutic use , Protein Binding , Protein Structure, Tertiary , Structure-Activity RelationshipABSTRACT
We report the synthesis and evaluation of aminoalkylguanidine analogues and derivatives in C57BL/KsJ db/db diabetic mice, following identification by random screening of 1a and 1b as potential antihyperglycemics and/or modulators of food intake. These compounds are related to galegine, a gamma,gamma-dimethylallylguanidine. Between the newly identified compounds, 1h N-(cyclopropylmethyl)- N'-(4-(aminomethyl)cyclohexylmethyl)guanidine showed the most balanced activity as antihyperglycemic and food intake-reducing agent.
