Improvement of patient outcomes following therapeutic optimization of chronic urticaria: two-year data from France as part of the international real-life AWARE study.

BACKGROUND: It is important to assess the burden of chronic urticaria (CU) with real-life studies. The AWARE study was performed in 36 countries over two years in CU patients resistant to H1-antihistamines. OBJECTIVES: To correlate patient-reported outcomes and available therapeutic options in CU patients. MATERIALS & METHODS: The AWARE study was a prospective, non-interventional, international study that included adult patients who have had H1-antihistamine-resistant CU for at least two months. The primary endpoints were the evolution of disease activity (UAS7), urticaria control (UCT), dermatological quality of life (DLQI) and treatment satisfaction (visual analogic scale) during a two-year follow-up. The data from French centres are reported. RESULTS: Ninety-two patients were included (mean age: 47.8 years; women: 70.7%; mean disease duration: 6.5 years; angioedema: 34.1%). The percentage of patients with CU treatment increased from 56.5% at inclusion to 86.0% after two years (for patients with non-sedative H1-antihistamines from 52.2% to 74.4%, and omalizumab from 2.2% to 25.6%). During the follow-up, the percentage of patients with UAS7 score <6 increased from 12.5% to 60.9%, and patients with well-controlled CU (UCT score >12) increased from 11.1% to 62.2%. The negative impact on quality of life (DLQI >10) decreased from 34.1% to 10.5%. The mean score of patient satisfaction for treatment increased from 4.6 to 7.6. CONCLUSION: The management of CU patients resistant to H1-antihistamines was not optimal at inclusion with uncontrolled disease, impaired quality of life and insufficient treatment. After a two-year follow-up, disease symptoms and quality of life improved, but the therapeutic management could be further optimized.

The burden of chronic spontaneous urticaria: unsatisfactory treatment and healthcare resource utilization in France (the ASSURE-CSU study).

Data on the clinical burden of chronic spontaneous urticaria (CSU) and economic consequences are lacking in France. To characterize the clinical and economic burden of CSU in symptomatic patients despite treatment by analysing data of French patients from the ASSURE-CSU study. ASSURE-CSU was an international observational study that included CSU patients with symptoms that lasted for 12 months or more despite treatment. Disease characteristics and healthcare resource use were obtained from medical records. Data on disease history, health-related quality of life (HR-QoL), and work productivity were collected from a patient survey. A total of 101 patients were analysed (76.2% female; mean age: 48.9 years) with moderate to severe disease (UAS7 score ≥16) in 43.4% and angioedema in 72.3%. The mean (S.D.) total scores of Chronic Urticaria Quality of Life (CU-Q2oL) and Dermatology Life Quality Index (DLQI) were 37.7 (22.3) and 9.7 (6.9), respectively, thus indicating a significant impact of the disease on HR-QoL. Mean absenteeism and presenteeism were 6.4% and 20.8%, respectively, with a mean loss of work productivity estimated at 20.7%. The mean (S.D.) total direct cost of CSU was €2,397 per patient per year and was mainly driven by therapies (€1,435) and inpatient costs (€859). The indirect costs for four weeks were mainly presenteeism (€421) and loss of work productivity (€420). CSU significantly impairs HR-QoL, which increases with the severity of the disease. The direct and indirect costs for the management of symptomatic CSU are an important economic burden.

Bacterial lipopolysaccharide induces type 2 deiodinase in cultured rat astrocytes.

In the brain, 3,5,3'-triiodothyronine, which binds to the thyroid hormone receptor with high affinity, is locally generated from thyroxine by type 2 iodothyronine deiodinase (D2) expressed mainly in astrocytes and tanycytes. We have investigated the effects of bacterial lipopolysaccharide (LPS) on D2 in cultured rat astrocytes. LPS induced D2 activity with a lag-time of 4-8 h and a maximum at 24 h. LPS also promoted D2 mRNA accumulation. Glucocorticoids enhanced both the basal and LPS-stimulated D2 activity and mRNA accumulation. These glucocorticoid effects were blocked by the glucocorticoid receptor antagonist RU486. Our results obtained with different specific signaling pathway inhibitors indicated that D2 induction by LPS required ERK and p38-MAPK signaling pathways. NF-κB inhibitor sulfasalazine blocked the effects of LPS on both D2 activity and mRNA accumulation. Hence, D2 induction by LPS appeared to implicate NF-κB pathway in astrocytes. NF-κB responsiveness of the rat dio2 gene was studied in astrocytes with dio2 5'-flanking region promoter assays. The long form of the dio2 promoter was transactivated by NF-κB. CCAAT/enhancer-binding protein ß, which is upregulated by LPS in astrocytes, increased the transcriptional activity of the dio2 promoter in its long or truncated forms containing CCAATs. Our observations, which demonstrate D2 induction by LPS in astrocytes and specify some characteristics of D2 induction mechanism, support the possible implication of brain D2 in adaptative responses to an infectious stress.

Oxidative stress regulates type 3 deiodinase and type 2 deiodinase in cultured rat astrocytes.

Type 2 deiodinase (D2) and type 3 deiodinase (D3) locally achieve the determination of the concentration of T3, which binds to the thyroid hormone receptor with high affinity. D2 converts T4 into T3, and D3 degrades T4 and T3. Neurons take up T3 released by astrocytes, the main cerebral site for the D2 expression. Because oxidative stress is believed to be involved in several neurological disorders, we explored the effects of oxidative stress on D3 and D2 in primary culture of rat astrocytes. H2O2 (250 microm) increased D3 activity with maximal effects around 8 h. Stimulation of D3 activity by H2O2 was synergistic with T4, phorbol ester, and also cAMP. H2O2 (250 microm) did not affect basal D2 activity but inhibited the stimulation of D2 activity by cAMP and factors implicating cAMP-independent pathways in astrocytes, TSH, and phorbol ester. N-Acetyl cysteine and selenium repletion, which respectively increase intracellular glutathione and glutathione peroxidase, inhibited D2 and D3 regulation by H2O2, whereas L-buthionine sulfoximine, which decreases intracellular glutathione, mimicked H2O2 effects. Oxidative stress up-regulated D3 and inhibited cAMP-stimulated D2 by transcriptional mechanisms. A decrease in cAMP by oxidative stress could contribute to the inhibition of cAMP-stimulated D2. Using specific inhibitors of signaling pathways, we show that the ERK pathway was required in D2 and D3 regulation by oxidative stress and that the p38 MAPK pathway was implicated in H2O2-induced D3. We suggest that the expected decrease in T3 might modulate the cellular injury of oxidative stress in some pathological brain conditions.

Hypoxia stabilizes type 2 deiodinase activity in rat astrocytes.

T(4) activation into T(3) is catalyzed by type 2 deiodinase (D2) in the brain. The rapid induction of D2 in astrocytes by transient brain ischemia has prompted us to explore the effects of hypoxia on D2 in cultures of astrocytes. Hypoxia (2.5% O(2)) of cultured astrocytes increased D2 activity, alone or in association with agents stimulating the cAMP pathway. Hypoxia had no effect on D2 mRNA accumulation. Cycloheximide did not block the effect of hypoxia on D2 activity and D2 half-life was enhanced under hypoxia demonstrating a posttranslational action of hypoxia. Furthermore, the D2 activity increase by hypoxia was not additive with the increase promoted by the proteasome inhibitor carbobenzoxy-L-leucyl-L-leucyl-L-leucinal (MG132). This strongly suggests that hypoxia leads to stabilization of D2 by slowing its degradation by the proteasome pathway. Hypoxia, in contrast to MG132, did not block the T(4)-induced D2 inactivation. A contribution of prolyl hydroxylase to the hypoxia effects on D2 was also suggested on the basis of increased D2 activity after addition of different prolyl hydroxylase inhibitors (cobalt chloride, desferrioxamine, dimethyloxalylglycine, dimethylsuccinate). Specific inhibitors of ERK, p38 MAPK, or phosphatidylinositol 3-kinase pathways were without any effect on hypoxia-increased D2 activity, eliminating their role in the effects of hypoxia. Interestingly, diphenyleneiodonium, an inhibitor of nicotinamide adenine dinucleotide phosphate oxidase inhibited the hypoxia-increased D2 indicating a role for some reactive oxygen species in the mechanism of D2 increase. Further studies are required to clarify the precise molecular mechanisms involved in the D2 stabilization by hypoxia.

Thyroid hormone deiodinases in the central and peripheral nervous system.

Thyroid hormones play a critical role in development and functioning of the nervous system. Deiodinases (type 2 [D2] and type 3 [D3]) contribute to the control of thyroid hormone action in the nervous system by regulating the local concentrations of triiodothyronine (T(3)), the main active thyroid hormone. Most brain T(3) is indeed locally formed by deiodination of thyroxine (T(4)). This reaction is catalyzed by D2 expressed in astrocytes throughout the brain and in tanycytes in the mediobasal hypothalamus. D3, which inactivates both T(4) and T(3), is mainly expressed in neurons also throughout the brain, with high expression in hippocampus and pyriform cortex. The regulation of deiodinases by many factors in addition to the thyroid hormones indicate that their role is not limited to mitigate the fluctuations in plasma T(4) and T(3). In contrast to the brain, deiodinases are not expressed in the adult peripheral nerve. Nerve lesions induce D2 in peripheral nerve sheaths and D3 in the endoneurial compartment containing Schwann cells. On the basis of available data summarized in this review, D2 and D3 clearly contribute to determine T(3) concentrations depending on the area of the nervous system, the state of development, and the pathophysiologic conditions.

Selective recruitment of p160 coactivators on glucocorticoid-regulated promoters in Schwann cells.

In the nervous system, glucocorticoid hormones play a major role during development and throughout life. We studied the mechanisms of action of the glucocorticoid receptor (GR) and its interactions with p160 coactivator family members [steroid receptor coactivator (SRC)-1 (a and e), SRC-2 and SRC-3] in mouse Schwann cells (MSC80). We found that the three p160s were expressed in MSC80 cells. We have shown by functional overexpression and RNA interference experiments that the recruitment of these coactivators by the GR is promoter dependent. A minimal promoter containing two glucocorticoid response elements, (GRE)2-TATA, recruits SRC-1 (a and e) and SRC-3, whereas SRC-2 is excluded. Within the context of the more complex mouse mammary tumor virus promoter, GR recruits SRC-1e and SRC-2, whereas SRC-1a and SRC-3 are not implicated. Furthermore, we have identified cytosolic aspartate aminotransferase as a GR target gene in MSC80 cells by microarray experiments. The GR recruits exclusively SRC-1e in the context of the cytosolic aspartate aminotransferase promoter. Because SRC-1 is the omnipresent coactivator of GR, we further investigated the interactions between GR and this coactivator in Schwann cells by reporter assays and immunocytochemistry experiments with deleted forms of SRC-1. We have shown that SRC-1 unexpectedly interacts with GR via its two nuclear receptor binding domains, thus providing a novel mechanism of GR signaling within the nervous system.