Development of XIAP Antagonists Based On De Novo 8,5-Fused Bicyclic Lactams.

In order to develop original water soluble antagonists of X-linked inhibitor of apoptosis protein (XIAP), a novel bicyclic scaffold was designed based on 8,5-fused bicyclic lactam. During its preparation, a spontaneous rearrangement from 8,5- to 7,5-fused bicyclic lactam was observed and confirmed by MS and NMR analyses, in particular the HMBC spectra. DFT calculations were performed to understand the corresponding mechanism. It was finally prevented through changing the reaction order in the synthesis route and a Smac mimetic with this core structure, ZJ-1 was successfully obtained. The structure of this new bicyclic scaffold was well confirmed by HRMS and NMR (1H, 13C, NOESY) analyses. ZJ-1 presented in addition a binding affinity to XIAP-BIR3, nearly 6 times better than that of AVPI, similar to the reported SM-128 in an in vitro fluorescence polarization (FP) assay. This preliminary result suggests that this new bicyclic scaffold could be very attractive in the development of novel anticancer agents targeting XIAP.

Association of Apolipoproteins B and A-1 With Markers of Vascular Health or Cardiovascular Events.

BACKGROUND: Apolipoprotein B (apoB) and apolipoprotein A-1 (apoA-1) are markers of lipoprotein metabolism. Although their relationship to cardiovascular disease has been well documented, little is known regarding their correlation to measures of vascular structure and function. This study was conducted to investigate the relationship between apoA-1, apoB, and measures of vascular function, as well their relationship to adverse cardiovascular events. Moreover, we evaluated whether apoB or the apoB/apoA-1 ratio was more closely related to vascular markers than was low-density lipoprotein cholesterol (LDL-C) or non-high-density lipoprotein cholesterol (non-HDL-C). METHODS: One thousand five hundred twenty-two healthy middle-aged men of the Firefighters and Their Endothelium (FATE) cohort were assessed for risk factors and flow-mediated dilatation (FMD), hyperemic velocity (VTI), and carotid intima-media thickness (CIMT). Participants were then followed for 7.2 ± 1.7 years. ApoA-1 and apoB levels were measured at baseline. RESULTS: ApoA-1 was not correlated with VTI, FMD, or CIMT, whereas apoB was significantly related to VTI and CIMT. Multiple regression analyses confirmed apoB as being related to both VTI (ß = -0.083; P = 0.001) and CIMT (ß = 0.055; P = 0.022) in models adjusted for age; blood pressure; high-density lipoprotein C (HDL-C), triglyceride and insulin levels; waist circumference; and C-reactive protein levels. In substituted models, LDL-C (ß = -0.092; P < 0.001) and non-HDL-C (ß = -0.089; P = 0.001) levels appeared to have the same degree of association as apoB for VTI but were not associated with CIMT. ApoB was found to be associated with cardiovascular events (hazard ratio, 1.349; 95% confidence interval, 1.073-1.695; P = 0.010). CONCLUSIONS: ApoB had an independent but weak relationship with indices of microvascular health. Nevertheless, it was associated with occurrence rates of adverse cardiovascular events.

Association of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) With Cardiovascular Risk in Primary Prevention.

OBJECTIVE: Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays an important role in the modulation of low-density lipoprotein metabolism. This study was conducted to evaluate the relationship between serum PCSK9 concentrations and measures of vascular health, subclinical atherosclerosis, and adverse cardiovascular events. The relationship between traditional risk factors and PCSK9 concentrations was also examined. APPROACH AND RESULTS: The cohort consisted of 1527 middle-aged men enrolled in the Firefighters and Their Endothelium (FATE) study, who were free of vascular disease and followed up over a mean period of 7.2±1.7 years. Baseline evaluation included assessment of traditional cardiovascular risk factors and measurements of flow-mediated dilation, reactive hyperemic velocity time integral, and carotid intima-media thickness. Biochemical parameters, including serum PCSK9 concentrations, were analyzed to determine predictors of vascular measures and to evaluate the role of PCSK9 in the occurrence of adverse cardiovascular events. Multivariate linear regression analyses indicated that body mass index, insulin, low-density lipoprotein-cholesterol, and triglycerides were independent predictors of PCSK9. Further modeling revealed no correlation between PCSK9 concentration and carotid intima media thickness, flow-mediated dilation, or reactive hyperemic velocity time integral. Analyses indicated no significant association between PCSK9 concentrations and cardiovascular event occurrences. CONCLUSIONS: Although correlated with low-density lipoprotein-cholesterol, insulin, and triglycerides, PCSK9 was not associated with measures of vascular function or structure. There was also no significant relationship between PCSK9 concentrations and cardiovascular events. Thus, although PCSK9 is an important therapeutic target to reduce circulating low-density lipoprotein-cholesterol concentrations, it is unlikely to be a biomarker of atherosclerotic risk or vascular health.

Fluid transport by human nonpigmented ciliary epithelial layers in culture: a homeostatic role for aquaporin-1.

We report for the first time that cultured nonpigmented human ciliary epithelial (NPE) cell layers transport fluid. Cells were grown to confluence on permeable membrane inserts, and fluid transport across the resulting cell layers was determined by volume clamp at 37 degrees C. These cell layers translocated fluid from the apical to the basal side at a steady rate of 3.6 microl x h(-1) x cm(-2) (n = 4) for 8 h. This fluid movement was independent of hydrostatic pressure and was completely inhibited by 1 mM ouabain, suggesting it arose from fluid transport. Mercuric chloride, a nonspecific but potent blocker of Hg(2+)-sensitive aquaporins, and aquaporin-1 antisense oligonucleotides both partially inhibited fluid transport across the cell layers, which suggests that water channels have a role in NPE cell homeostasis. In addition, these results suggest that of the two ciliary epithelial layers in tandem, the NPE layer by itself can transport fluid. This cultured layer, therefore, constitutes an interesting model that may be useful for physiological and pharmacological characterization of ciliary epithelial fluid secretion.