Asthma control and exacerbations in patients with severe asthma treated with omalizumab in Portugal

The analysis of outcomes from patients with severe asthma treated with omalizumab, using real-life prospective data, should contribute to future informed decisions about this treatment in Portugal. The aim of this study was to assess the clinical effect of omalizumab in Portuguese patients with severe persistent allergic asthma, considering specifically asthma control and exacerbations. This was an observational, prospective, multicentre study. Data were collected at routine care over a 12-month period. Disease control was defined by Control of Allergic Rhinitis and Asthma Test (CARAT) global score >24. All asthma patients already under treatment with omalizumab in 7 departments from 6 Portuguese hospitals were included (n=48). Most (77%) patients were female and the mean (SD) age was 51.9 (10.2) years old. During the study period, asthma was controlled in 34% of the visits and the 12-month exacerbation rate was 1.7 per patient (0.6 with unscheduled medical care). One-third of the patients needed unscheduled medical care because of asthma and 29% had to start or increase oral corticosteroid. There was still a 41% reduction in the total sum of oral corticosteroids usage from the first to the last trimester of the study. During routine treatment with omalizumab, Portuguese patients with severe asthma achieved asthma control in 1/3 of the visits and only 1/3 needed unscheduled or Emergency Room care because of asthma exacerbations. These outcomes support the maintenance of the clinical effect during treatment with omalizumab in routine care in Portugal.

Peroxisome proliferator-activated receptor gamma ligands inhibit development of atherosclerosis in LDL receptor-deficient mice

The peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear receptor that regulates fat-cell development and glucose homeostasis and is the molecular target of a class of insulin-sensitizing agents used for the management of type 2 diabetes mellitus. PPARgamma is highly expressed in macrophage foam cells of atherosclerotic lesions and has been demonstrated in cultured macrophages to both positively and negatively regulate genes implicated in the development of atherosclerosis. We report here that the PPARgamma-specific agonists rosiglitazone and GW7845 strongly inhibited the development of atherosclerosis in LDL receptor-deficient male mice, despite increased expression of the CD36 scavenger receptor in the arterial wall. The antiatherogenic effect in male mice was correlated with improved insulin sensitivity and decreased tissue expression of TNF-alpha and gelatinase B, indicating both systemic and local actions of PPARgamma. These findings suggest that PPARgamma agonists may exert antiatherogenic effects in diabetic patients and provide impetus for efforts to develop PPARgamma ligands that separate proatherogenic activities from antidiabetic and antiatherogenic activities.

Cholesteryl ester transfer between high density lipoprotein and phospholipid bilayers

High density lipoprotein-associated cholesteryl esters (HDL CE) are taken up by many cells without parallel uptake of HDL apoproteins, a pathway we have termed "selective uptake." The first step in this pathway, the reversible incorporation of HDL CE into the plasma membrane, is the subject of the present study. To examine the role of membrane proteins, the rate of HDL CE incorporation into isolated rat liver plasma membrane was compared with the rate of incorporation into synthetic membranes devoid of protein. Both membrane systems exhibited saturable uptake of CE, and at rates that were similar (t1/2 approximately 2 h, measured with 50 micrograms of HDL protein). Addition of unlabeled HDL to "chase" CE tracer from the biological and synthetic membranes revealed two kinetically distinct CE pools (t1/2 approximately 0.5 h and t1/2 approximately 30 h). Both biological and synthetic membranes accepted similar amounts of CE into both pools, with a maximum incorporation of 2-4 mol % relative to membrane phospholipids. CE transfer between HDL and membranes was kinetically second-order, in contrast to the first-order transfer of unesterified cholesterol. There was no evidence for direct participation of any apolipoprotein in CE uptake; CE in HDL or in protein-free microemulsions of similar particle size transferred to membranes at similar rates. To examine the possibility that CE transfer requires transient fusion of the HDL amphipathic coat with the membrane outer leaflet, radiolabeled cardiolipin was incorporated into either HDL particles or into synthetic membranes as an amphipathic coat marker that does not diffuse through the aqueous phase; transfer between HDL and membranes was not observed. Thus, CE are transferred between HDL and cell membranes in a collision-mediated process that does not involve amphipathic coat fusion and is not dependent on either membrane protein or apolipoproteins.