-
Maria Carla Marcotullio,
Federica Messina,
Massimo Curini,
Antonio Macchiarulo, Marco Cellanetti,
Donata Ricci,
Laura Giamperi,
Anahi Bucchini,
Alba Minelli,
Anna Lisa Mierla,
Ilaria Bellezza
[show abstract]
[hide abstract]
ABSTRACT: By bioguided fractionation of the hexane extract of Commiphora erythraea resin we isolated four furanosesquiterpenoids that were tested for their protective activity against oxidative stress. Furanodienone and 1,10(15)-furanogermacra-dien-6-ones showed to be potent inhibitors of lipid peroxidation (IC(50) of -0.087 μM), being more active than the methoxylated analogues. Furthermore, using BV2 microglial cells, we found that furanodienone from C. erythraea is able to counteract LPS-induced cell death and decrease LPS-induced NO generation thus protecting microglial cells from LPS-induced cytotoxicity. Finally, docking studies were undertaken to gain insight into the possible binding mode of the isolated compounds at 5-LOX binding site.
Molecules 01/2011; 16(12):10357-69. · 2.39 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The Small Heterodimer Partner (SHP) is an orphan nuclear receptor and an atypical member of the nuclear receptor superfamily Since its discovery, a growing body of evidences have pointed out a pivotal role for SHP in the transcriptional regulation of a variety of target genes involved in diverse metabolic pathways. While we have previously developed a homology model of the structure of SHP that was instrumental to identify a putative ligand binding pocket and suggest the possibility of the development of synthetic modulators, others reported that some atypical retinoids may represent the first synthetic ligands for this receptor. In this work, we report a combined computational approach aimed at shedding further lights on the binding mode and mechanism of action of some atypical retinoids as ligands of SHP. The results have been instrumental to design mutagenesis experiments whose preliminary data suggest the presence of a functional site in SHP as defined by residues Phe96, Arg138 and Arg238. While further experimental studies are ongoing, these findings constitute the basis for the design and identification of novel synthetic modulators of SHP functions.
Journal of Computer-Aided Molecular Design 09/2010; 24(11):943-56. · 3.39 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We identified three heterozygous nonsynonymous single nucleotide polymorphisms in the small heterodimer partner (SHP, NROB2) gene in normal subjects and CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy)-like patients, including two novel missense mutations (p.R38H, p.K170N) and one of the previously reported polymorphism (p.G171A). Four novel heterozygous mutations were also identified in the intron ((Intron)1265T-->A), 3'-untranslated region ((3'-UTR)101C-->G, (3'-UTR)186T-->C), and promoter ((Pro)-423C-->T) of the SHP gene. The exonic R38H and K170N mutants exhibited impaired nuclear translocation. K170N made SHP more susceptible to ubiquitination mediated degradation and blocked SHP acetylation, which displayed lost repressive activity on its interacting partners ERRgamma and HNF4alpha but not LRH-1. In contrast, G171A increased SHP mRNA and protein expression and maintained normal function. In general, the interaction of SHP mutants with LRH-1 and EID1 was enhanced. K170N also markedly impaired the recruitment of SHP, HNF4alpha, HDAC1, and HDAC3 to the apoCIII promoter. Molecular dynamics simulations of SHP showed that G171A stabilized the nuclear receptor boxes, whereas K170N promoted the conformational destabilization of all the structural elements of the receptor. This study suggests that genetic variations in SHP are common among human subjects and the Lys-170 residue plays a key role in controlling SHP ubiquitination and acetylation associated with SHP protein stability and repressive function.
Journal of Biological Chemistry 08/2010; 285(32):24871-81. · 4.77 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We identified three heterozygous nonsynonymous single nucleotide polymorphisms in the small heterodimer partner (SHP, NROB2) gene in normal subjects and CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy)-like
patients, including two novel missense mutations (p.R38H, p.K170N) and one of the previously reported polymorphism (p.G171A).
Four novel heterozygous mutations were also identified in the intron (Intron1265T→A), 3′-untranslated region (3′-UTR101C→G, 3′-UTR186T→C), and promoter (Pro-423C→T) of the SHP gene. The exonic R38H and K170N mutants exhibited impaired nuclear translocation. K170N made SHP more
susceptible to ubiquitination mediated degradation and blocked SHP acetylation, which displayed lost repressive activity on
its interacting partners ERRγ and HNF4α but not LRH-1. In contrast, G171A increased SHP mRNA and protein expression and maintained
normal function. In general, the interaction of SHP mutants with LRH-1 and EID1 was enhanced. K170N also markedly impaired
the recruitment of SHP, HNF4α, HDAC1, and HDAC3 to the apoCIII promoter. Molecular dynamics simulations of SHP showed that
G171A stabilized the nuclear receptor boxes, whereas K170N promoted the conformational destabilization of all the structural
elements of the receptor. This study suggests that genetic variations in SHP are common among human subjects and the Lys-170
residue plays a key role in controlling SHP ubiquitination and acetylation associated with SHP protein stability and repressive
function.
Journal of Biological Chemistry 08/2010; 285(32):24871-24881. · 4.77 Impact Factor
