Multifunctional Heterometallic IrIII -AuI Probes as Promising Anticancer and Antiangiogenic Agents.

A new class of emissive cyclometallated IrIII -AuI complexes with a bis(diphenylphosphino) methanide bridging ligand was successfully synthesised from the diphosphino complex [Ir(N^C)2 (dppm)]+ (1). The different gold ancillary ligand, a triphenylphosphine (2), a chloride (3) or a thiocytosine (4) did not reveal any significant effect on the photophysical properties, which are mainly due to metal-to-ligand charge-transfer (3 MLCT) transitions based on IrIII . However, the AuI fragment, along with the ancillary ligand, seemed crucial for the bioactivity in A549 lung carcinoma cells versus endothelial cells. Both cell types display variable sensitivities to the complexes (IC50 =0.6-3.5 µM). The apoptotic pathway is activated in all cases, and paraptotic cell death seems to take place at initial stages in A549 cells. Species 2-4 showed at least dual lysosomal and mitochondrial biodistribution in A549 cells, with an initial lysosomal localisation and a possible trafficking process between both organelles with time. The bimetallic IrIII -AuI complexes disrupted the mitochondrial transmembrane potential in A549 cells and increased reactive oxygen species (ROS) generation and thioredoxin reductase (TrxR) inhibition in comparison with that displayed by the monometallic complex 1. Angiogenic activity assays performed in endothelial cells revealed the promising antimetastatic potential of 1, 2 and 4.

New contributions to the study of common double mutants in the human LDL receptor gene.

Variations in the gene encoding the low-density lipoprotein receptor (LDLR) can cause familial hypercholesterolemia (FH), one of the most common inherited metabolic disorders in humans. The functional effects of the p.Gln92Glu and p.Asn564His alterations are predicted as benign, but the c.313 + 1G>C and p.Lys799_Phe801del changes are believed to cause disease. Although p.Gln92Glu and c.313 + 1G>C have been observed only in Spain, p.Asn564His and p.Lys799_Phe801del are widespread in Western Europe. In order to estimate the ages (t generations) of these four variants of the gene, to determine their possible origin and to consider the influence of age and selective pressure on their spread, we analyzed 86 healthy individuals and 126 FH patients in Spain. Most of the FH patients investigated carried two of these four LDLR variants simultaneously, while only one patient carried three of them simultaneously. Haplotype analyses were based on five LDLR SNPs: c.81T>C, c.1413G>A, c.1725C>T, c.1959T>C and c.2232G>A. The results suggest that p.Gln92Glu and c.313 + 1G>C arose at about the same time (99 and 103 generations ago, respectively) in the CACTG haplotype and that p.Asn564His and p.Lys799_Phe801del appeared in the CGCCG haplotype and might be slightly more recent variations (92 and 95 generations ago, respectively). Low selective pressures could explain the maintenance of these variants in spite of their ages. The origin of p.Gln92Glu and c.313 + 1G>C appears to be in Spain whereas p.Asn564His and p.Lys799_Phe801del could have been introduced in Spain by Celtic migrations in the seventh to fifth centuries BC.

FABP4 plasma levels are increased in familial combined hyperlipidemia.

The lipid profile of familial combined hyperlipidemia (FCHL) shares some characteristics with atherogenic dyslipidemia seen in diabetes, metabolic syndrome, and obesity. Adipocyte fatty acid-binding protein 4 (FABP4) appears to be a determinant of atherogenic dyslipidemia. We examined relationships between FABP4 plasma concentrations, dyslipidemia, and metabolic variables in patients with FCHL. We studied 273 unrelated FCHL patients and 118 control subjects. FABP4 was higher in FCHL than controls, with mean levels of 21.8 (10.1) microg/l and 19.2 (9.2) microg/l, respectively (adjusted P= 0.012). In FCHL, FABP4 correlated to body mass index (BMI), waist circumference, insulin levels, and homeostasis model assessment (HOMA) index (all P< 0.05), but not to lipid levels, whereas in obese patients, FABP4 correlated to triglyceride levels (r = 0.303, P= 0.014) and very low density lipoprotein size (r = 0.502, P = 0.001), as determined by nuclear magnetic resonance. Associations of FABP4 with BMI and waist circumference, but not with insulin levels, persisted in this subgroup. Plasma FABP4 does not influence the lipid phenotype of FCHL. In a small subgroup of obese FCHL, FABP4 levels were associated with triglyceride-rich lipoproteins independent of insulin resistance. These results support a hyperlipidemic mechanism of FCHL different from similar metabolic conditions where fat mass is strongly related to FABP4 and hypertriglyceridemia.

Frequency of low-density lipoprotein receptor gene mutations in patients with a clinical diagnosis of familial combined hyperlipidemia in a clinical setting.

OBJECTIVES: The purpose of this study was to determine the frequency of mutations in the low-density lipoprotein receptor (LDLR) and apolipoprotein B (APOB) genes in consecutive patients with a clinical diagnosis of familial combined hyperlipidemia (FCH) in a nonresearch setting. BACKGROUND: The lipid phenotype frequently overlaps in familial hypercholesterolemia (FH) and FCH. Detection of causative mutations in LDLR or APOB provides an unequivocal diagnosis of FH, but such genetic testing has not been systematically performed in FCH. METHODS: We used Lipochip (Progenika, Derio, Spain), a microarray that includes 203 causative mutations in LDLR and 4 APOB defects, to investigate 143 unrelated FCH patients. RESULTS: Mutations of LDLR were found in 28 patients (overall prevalence, 19.6%). No APOB defects were found. Compared with patients who had a normal LDLR gene, patients with mutations had lower waist circumference (p = 0.02); significantly (p < 0.005) higher total cholesterol, non-high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and apoB; nonsignificantly (p = 0.063) lower triglycerides; and a lower frequency of diabetes mellitus (22% vs. 0%, respectively; p = 0.002). Total cholesterol and apoB levels showed the best receiver-operator characteristics curves in the prediction of LDLR mutations, with areas under the curve (95% CI: of 0.750 (95% confidence interval [CI]: 0.647 to 0.853) and 0.744 (95% CI: 0.636 to 0.851), respectively. Total cholesterol of 335 mg/dl and apoB of 185 mg/dl were the best thresholds for diagnosis of LDLR mutations. CONCLUSIONS: Screening for LDLR defects is advisable for patients with a clinical diagnosis of FCH showing high total cholesterol or apoB levels. Diagnostic criteria for FH should not exclude patients whose personal and familial lipid values appear to fit the clinical criteria of FCH.