Thalidomide reduces IL-18, IL-8 and TNF-alpha release from alveolar macrophages in interstitial lung disease

Thalidomide exhibits diverse actions of anti-inflammation, immunomodulation and anti-angiogenesis. The efficacy of thalidomide treatment in sarcoidosis with lupus pernio is thought to be due to inhibition of tumour necrosis factor (TNF)-alpha. The mechanisms that underlie the properties of thalidomide are still unclear in interstitial lung disease. The current authors investigated the potential inhibitory effects of thalidomide at concentrations of 0.1, 0.01 and 0.001 mM on the production of transforming growth factor-beta, TNF-alpha, interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70, IL-12p40 and IL-18 by alveolar macrophages from bronchoalveolar lavage in patients with sarcoidosis (n = 8), hypersensitivity pneumonitis (HP; n = 8) and idiopathic pulmonary fibrosis (IPF; n = 12). In sarcoidosis and HP patients, thalidomide induced a dose-dependent, partial suppression of lipopolysacchride (LPS)-stimulated TNF-alpha, IL-12p40 and IL-18 release. At the highest thalidomide concentration (0.1 mM), LPS-stimulated IL-8 production was also suppressed. In IPF patients, although spontaneous production of TNF-alpha, IL-12p40, IL-18 and IL-8 was lower than in sarcoidosis and HP patients, with LPS stimulation the cytokines were significantly elevated and also partially inhibited by thalidomide. In conclusion, thalidomide has the potential to improve the therapeutic regimens for sarcoidosis, hypersensitivity pneumonitis and idiopathic pulmonary fibrosis by reducing tumour necrosis factor-alpha, interleukin-12p40, interleukin-18 and interleukin-8 production.

Expression of tumour necrosis factor receptors by bronchoalveolar cells in hypersensitivity pneumonitis

Tumour necrosis factor receptors (TNFR) and the Fas receptor (FasR) have been implicated in the pathogenesis of interstitial lung diseases. The current authors examined the expression of TNFR-1, TNFR-2 and FasR by bronchoalveolar cells in hypersensitivity pneumonitis (HP). Cell surface receptor expression on bronchoalveolar lavage cells was analysed by immunocytochemistry in 11 HP patients, 11 idiopathic pulmonary fibrosis (IPF) patients and 10 controls. TNFR-1, TNFR-2 and FasR were expressed on a higher percentage of alveolar macrophages (AM) in HP compared with controls and IPF patients. TNFR-2 and FasR expression on lymphocytes was also higher in HP than in controls and in IPF. TNFR-1, TNFR-2 and FasR expression correlated positively with the percentage of lymphocytes, and negatively with the percentage of AM in HP. Expression of TNFR-1 on AM and TNFR-2 on lymphocytes correlated with the percentage of neutrophils in HP. In conclusion, this study shows evidence of altered expression of tumour necrosis factor superfamily receptors in hypersensitivity pneumonitis.

Copper sorption by chitosan in the presence of citrate ions: influence of metal speciation on sorption mechanism and uptake capacities

The presence of organic ligands in a solution containing metal ions modifies metal speciation, which in turn changes the sorption mechanism, optimum pH range and maximum sorption capacity. The present work investigates the sorption of copper by chitosan in the presence of citrate at different metal/ligand ratios. Copper uptake in acidic solution takes place through electrostatic attraction between the protonated amine groups of chitosan and anionic copper-citrate complexes (mainly Cu(OH)L2- but also a small fraction of CuL-). Sorption was negligible below pH 3 due to competition from dissociated anionic ligand and counter ions brought about by dissociation of the acid used for pH control. Actually, copper sorption begins to be significant when the fraction of anionic copper-complexes exceeds that of anionic copper-free ligand. So sorption capacity strongly increases up to pH 4.5-5.5. Above pH 5.5, the progressive decrease of amine protonation leads to a linear decrease in sorption capacity. An excess of ligand leads to an increase in the fraction of free dissociated (anionic) ligand that may compete for electrostatic attraction on protonated amine groups and therefore leads to a decrease in sorption capacities.

Caspases, the Enemy Within, and Their Role in Oxidative Stress-Induced Apoptosis of Inner Ear Sensory Cells

This review covers the general roles of members of the cysteine protease family of caspases in the process of apoptosis (programmed cell death) looking at their participation in both the "extrinsic" cell death receptor and the "intrinsic" mitochondrial cell death pathways. It defines the difference between initiator and effector caspases and shows the progression of caspase activations that ends up in the apoptotic cell death and elimination of a damaged cell. The review then presents what is currently know about the participation of caspases in the programmed cell death of inner ear sensory cells during the process of normal development and maturation of the inner ear and their importance in this process as illustrated by the results of caspase-3 gene knockout experiments. The participation of specific caspases and the sequence of their activation in the elimination (apoptosis) of damaged sensory cells from adult inner ears after an injury that generates oxidative stress are reviewed. Both the possibility and the potential efficacy of caspase inhibition with a broad-spectrum pancaspase inhibitor as an interventional therapy to treat and rescue oxidative stress-damaged inner ear sensory cells from apoptosis are presented and discussed.

[Pulmonary fibrosis. Classification, diagnosis, therapy]

A new classification of the idiopathic interstitial pneumonia has recently been proposed, defining idiopathic pulmonary fibrosis (IPF) more rigorously and in contrast to further subentities. The new classification is of prognostic and clinical relevance. Diagnosis requires a combined clinical, radiological and pathological effort. In patients with characteristic clinical and HR-CT findings, the diagnosis of IPF can be made with sufficient confidence without surgical lung biopsy. Recent evidence suggests that the primary pathogenetic event in IPF involves epithelial injury and abnormal wound heeling. This explains the ineffectiveness of the usual anti-inflammatory therapy in the majority of patients. Since no antifibrotic drugs are available at present, the recommended standard therapy is a combination of prednisone with azathioprine or cyclophosphamide. New antifibrotic molecules are already tested in clinical trials.

Idiopathic bronchiolitis mimicking diffuse panbronchiolitis

Diffuse panbronchiolitis (DPB) is a distinct sinobronchial syndrome which has been almost exclusively reported in East Asia; only a few cases have been observed in non-Asians so far. Since 1990, when one of us described the first European case, we have screened all patients presenting with a clinical, physiopathological and radiological pattern compatible with DPB, in order to assess if the paucity of proven cases in Europe could reflect a lack of awareness of this disease among both pulmonologists and pathologists. Over a 10-years period we identified four additional DPBs, but also interestingly observed five cases of "idiopathic" bronchiolitis (IB) that had both clinical symptoms and high-resolution computed tomography (HRCT) findings indistinguishable from those of DPB, but did not show the typical histological changes. All these patients were Caucasians and presented with dyspnea, productive cough, an obstructive or mixed impairment on pulmonary function tests and chest HRCT features strongly suggesting a grade II to IV DPB. We suggest that diseases classified as IB in this study might be homogeneous entities which are clinically and radiologically similar to DPB.

Differential gene expression of adenosine A1, A2a, A2b, and A3 receptors in the human enteric nervous system

Adenosine receptors (ADORs) in the enteric nervous system may be of importance in the control of motor and secretomotor functions. Gene expression and distribution of neural adenosine A1, A2a, A2b, or A3 receptors (Rs) in the human intestine was investigated using immunochemical, Western blotting, RT-PCR, and short-circuit current (I(sc)) studies. Adenosine A1R, A2aR, A2bR, or A3R mRNAs were differentially expressed in neural and nonneural layers of the jejunum, ileum, colon, and cecum and in HT-29, T-84, T98G, and Bon cell lines. A1R, A2aR, A2bR, and A3R immunoreactivities (IRs) were differentially expressed in PGP 9.5-immunoreactive neurons. A2bR IR occurs exclusively in 50% of submucosal vasoactive intestinal peptide (VIP) neurons (interneurons, secretomotor or motor neurons) in jejunum, but not colon; A2aR is also found in other neurons. A3R IR occurs in 57% of substance P-positive jejunal submucosal neurons (putative intrinsic primary afferent neurons) and less than 10% of VIP neurons. Western blots revealed bands for A3R at 44 kDa, 52 kDa, and 66 kDa. A2aR and A2bR are coexpressed in enteric neurons and epithelial cells. 5'-N-methylcarboxamidoadenosine or carbachol evoked an increase in I(sc). A2bR IR is more prominent than A2aR IR in myenteric neurons, nerve fibers, or glia. A1R is expressed in jejunal myenteric neurons and colonic submucosal neurons. Regional differences also exist in smooth muscle expression of ADOR IR(s). It is concluded that neural and nonneural A1, A2a, A2b, and A3Rs may participate in the regulation of neural reflexes in the human gut. Clear cell and regional differences exist in ADOR gene expression, distribution, localization, and coexpression.