17 research outputs found
Therapeutic targeting of cathepsin C::from pathophysiology to treatment
Cathepsin C (CatC) is a highly conserved tetrameric lysosomal cysteine dipeptidyl aminopeptidase. The best characterized physiological function of CatC is the activation of pro-inflammatory granule-associated serine proteases. These proteases are synthesized as inactive zymogens containing an N-terminal pro-dipeptide, which maintains the zymogen in its inactive conformation and prevents premature activation, which is potentially toxic to the cell. The activation of serine protease zymogens occurs through cleavage of the N-terminal dipeptide by CatC during cell maturation in the bone marrow. In vivo data suggest that pharmacological inhibition of pro-inflammatory serine proteases would suppress or attenuate deleterious effects of inflammatory/auto-immune disorders mediated by these proteases. The pathological deficiency in CatC is associated with Papillon-LefĂšvre syndrome. The patients however do not present marked immunodeficiency despite the absence of active serine proteases in immune defense cells. Hence, the transitory pharmacological blockade of CatC activity in the precursor cells of the bone marrow may represent an attractive therapeutic strategy to regulate activity of serine proteases in inflammatory and immunologic conditions. A variety of CatC inhibitors have been developed both by pharmaceutical companies and academic investigators, some of which are currently being employed and evaluated in preclinical/clinical trials
Functional study of macrophage MMp-12 in order to its therapeutic targeting in chronic obstructive pulmonary disease
La bronchopneumopathie chronique obstructive ou BPCO est une atteinte des voies respiratoires causĂ©e par le tabagisme. Cette maladie pulmonaire chronique et non rĂ©versible pour laquelle il nây pas de traitement curatif se caractĂ©rise par une inflammation permanente du tractus respiratoire. Celle-ci est due Ă lâafflux massif de cellules de lâinflammation, principalement des neutrophiles et macrophages, qui libĂšrent aprĂšs activation, de nombreuses protĂ©ases actives. Ces protĂ©ases vont alors dĂ©grader les protĂ©ines de structure comme lâĂ©lastine, ce qui va entraĂźner la dĂ©gradation progressive des alvĂ©oles pulmonaires et au final une altĂ©ration de plus en plus marquĂ©e de la fonction respiratoire. Parmi les diffĂ©rentes protĂ©ases prĂ©sentes dans le poumon, la MMP-12 de macrophage, joue un rĂŽle clĂ© dans la physiopathologie de la maladie.Chronic obstructive pulmonary disease or COPD is a lung disease caused by tobacco smoking. This is a chronic and non reversible disease for which no curative treatment is available yet. Permanent inflammation of the airways is a hallmark of COPD because immune cells such as neutrophils and macrophages are continuously recruited. Once activated, these cells release numerous active proteases which participate to the degradation of structural proteins of the lungs such as elastin, leading to lung emphysema as a consequence of lung alveoli degradation. Among the different proteases found in the lungs, macrophage MMP-12 has been reported to play a key pathogenic role in COPD development
Processing and Maturation of Cathepsin C Zymogen: A Biochemical and Molecular Modeling Analysis
Cysteine cathepsin C (CatC) is a ubiquitously expressed, lysosomal aminopeptidase involved in the activation of zymogens of immune-cell-associated serine proteinases (elastase, cathepsin G, proteinase 3, neutrophil serine proteinase 4, lymphocyte granzymes, and mast cell chymases). CatC is first synthetized as an inactive zymogen containing an intramolecular chain propeptide, the dimeric form of which is processed into the mature tetrameric form by proteolytic cleavages. A molecular modeling analysis of proCatC indicated that its propeptide displayed a similar fold to those of other lysosomal cysteine cathepsins, and could be involved in dimer formation. Our in vitro experiments revealed that human proCatC was processed and activated by CatF, CatK, and CatV in two consecutive steps of maturation, as reported for CatL and CatS previously. The unique positioning of the propeptide domains in the proCatC dimer complex allows this order of cleavages to be understood. The missense mutation Leu172Pro within the propeptide region associated with the PapillonâLefĂšvre and HaimâMunk syndrome altered the proform stability as well as the maturation of the recombinant Leu172Pro proform
Osteopontin as a Link between Inflammation and Cancer: The Thorax in the Spotlight
The glycoprotein osteopontin (OPN) possesses multiple functions in health and disease. To this end, osteopontin has beneficial roles in wound healing, bone homeostasis, and extracellular matrix (ECM) function. On the contrary, osteopontin can be deleterious for the human body during disease. Indeed, osteopontin is a cardinal mediator of tumor-associated inflammation and facilitates metastasis. The purpose of this review is to highlight the importance of osteopontin in malignant processes, focusing on lung and pleural tumors as examples
Les produits minceurs (conseils Ă l'officine)
Ces derniĂšres annĂ©es, les diktats de la mode ont imposĂ© le culte de la minceur. Les laboratoires ont alors envahi le marchĂ© de produits divers et variĂ©s. Si leur efficacitĂ© est souvent remise en cause par des associations de consommateurs, paradoxalement nombreux sont ceux, rĂȘvant toujours de l idĂ©al minceur, qui espĂšrent en tirer un bĂ©nĂ©fice mĂȘme si de façon rĂ©currente des scandales Ă©clatent dĂ©nonçant la dangerositĂ© de certains d entre eux. Le pharmacien au centre de l offre et de la demande doit constamment se tenir informĂ© de leurs intĂ©rĂȘts et de leurs possibles effets indĂ©sirables afin d assurer un conseil Ă©clairĂ© aux personnes souhaitant perdre du poids. On trouvera ici la critique de certains moyens proposĂ©s ainsi que les conseils qui leur seront associĂ©s.These last few year, the fashion s dictates have imposed the worship of slimness. Then, the market has been flooded by a large range of products by the laboratories. While their effectiveness is often questioned by consumers associations, many people paradoxically, still dream of the ideal slimness, hope to get advantage of them even if scandals break repeatedly denouncing the dangers of some of them . The chemist in the center of this offer and demand must keep be held informed about its interest to assure an advice to people wishing to lose weight. This section contains the critics of some means offered as well as advice wich will be linked to them.AMIENS-BU SantĂ© (800212102) / SudocSudocFranceF
New insights into the substrate specificity of macrophage elastase MMP-12
International audienceMacrophage elastase, or MMP-12, is mainly produced by alveolar macrophages and is believed to play a major role in the development of chronic obstructive pulmonary disease (COPD). The catalytic domain of MMP-12 is unique among MMPs in that it is very highly active on numerous substrates including elastin. However, measuring MMP-12 activity in biological fluids has been hampered by the lack of highly selective substrates. We therefore synthesized four series of fluorogenic peptide substrates based on the sequences of MMP-12 cleavage sites in its known substrates. Human MMP-12 efficiently cleaved peptide substrates containing a Pro at P3 in the sequence ProX-X down arrow Leu but lacked selectivity towards these substrates compared to other MMPs, including MMP-2, MMP-7, MMP-9 and MMP-13. On the contrary, the substrate Abz-RNALAVERTAS-EDDnp derived from the CXCR5 chemokine was the most selective substrate for MMP-12 ever reported. All substrates were cleaved more efficiently by full-length MMP-12 than by its catalytic domain alone, indicating that the C-terminal hemopexin domain influences substrate binding and/or catalysis. Docking experiments revealed unexpected interactions between the peptide substrate Abz-RNALAVERTAS-EDDn and MMP-12 residues. Most of our substrates were poorly cleaved by murine MMP-12 suggesting that human and murine MMP-12 have different substrate specificities despite their structural similarity
Caspase-11 and AIM2 inflammasome are involved in smoking-induced COPD and lung adenocarcinoma
Cigarette smoking is the leading risk factor for COPD and lung cancer establishment. Epidemiologically, COPD patients are 6.35 times more likely to develop lung cancer.
To mimic COPD, we exposed mice to nose-only cigarette smoke and used human samples of lung adenocarcinoma patients according to the smoking and COPD status.
Smoking C57Bl/6N mice had higher enlargement of alveoli, deposition of collagen and mucus production, associated to the release of IL-1-like cytokines, such as IL-1α and IL-1ÎČ at early time points and IL-18 at later time points. AIM2 expression was higher in lung recruited dendritic cells and macrophages in smoking mice, associated to the activation of caspase-11, rather than caspase-1. In support,129Sv mice, which are dysfunctional for caspase-11, had lower collagen deposition and mucus production, associated to lower release of IL-1-like and fibrotic TGFÎČ. Interestingly, higher expression of AIM2 in non-cancerous tissue of smoking COPD adenocarcinoma patients was correlated to a higher hazard ratio of poor survival rate than in patients who presented lower levels of AIM2.
We found that AIM2 inflammasome is at the crossroad between COPD and lung cancer in that its higher presence is correlated to lower survival rate of smoking COPD adenocarcinoma patients
Cathepsin C inhibition as a potential treatment strategy in cancer
International audienceEpidemiological studies established an association between chronic inflammation and higher risk of cancer. Inhibition of proteolytic enzymes represents a potential treatment strategy for cancer and prevention of cancer metastasis. Cathepsin C (CatC) is a highly conserved lysosomal cysteine dipeptidyl aminopeptidase required for the activation of pro-inflammatory neutrophil serine proteases (NSPs, elastase, proteinase 3, cathepsin G and NSP-4). NSPs are locally released by activated neutrophils in response to pathogens and non-infectious danger signals. Activated neutrophils also release neutrophil extracellular traps (NETs) that are decorated with several neutrophil proteins, including NSPs. NSPs are not only NETs constituents but also play a role in NET formation and release. Although immune cells harbor large amounts of CatC, additional cell sources for this protease exists. Upregulation of CatC expression was observed in different tissues during carcinogenesis and correlated with metastasis and poor patient survival. Recent mechanistic studies indicated an important interaction of tumor-associated CatC, NSPs, and NETs in cancer development and metastasis and suggested CatC as a therapeutic target in a several cancer types. Cancer cell-derived CatC promotes neutrophil recruitment in the inflammatory tumor microenvironment. Because the clinical consequences of genetic CatC deficiency in humans resulting in the elimination of NSPs are mild, small molecule inhibitors of CatC are assumed as safe drugs to reduce the NSP burden. Brensocatib, a nitrile CatC inhibitor is currently tested in a phase 3 clinical trial as a novel anti-inflammatory therapy for patients with bronchiectasis. However, recently developed CatC inhibitors possibly have protective effects beyond inflammation. In this review, we describe the pathophysiological function of CatC and discuss molecular mechanisms substantiating pharmacological CatC inhibition as a potential strategy for cancer treatment
Processing and Maturation of Cathepsin C Zymogen: A Biochemical and Molecular Modeling Analysis
International audienceCysteine cathepsin C (CatC) is a ubiquitously expressed, lysosomal aminopeptidase involved in the activation of zymogens of immune-cell-associated serine proteinases (elastase, cathepsin G, proteinase 3, neutrophil serine proteinase 4, lymphocyte granzymes, and mast cell chymases). CatC is first synthetized as an inactive zymogen containing an intramolecular chain propeptide, the dimeric form of which is processed into the mature tetrameric form by proteolytic cleavages. A molecular modeling analysis of proCatC indicated that its propeptide displayed a similar fold to those of other lysosomal cysteine cathepsins, and could be involved in dimer formation. Our in vitro experiments revealed that human proCatC was processed and activated by CatF, CatK, and CatV in two consecutive steps of maturation, as reported for CatL and CatS previously. The unique positioning of the propeptide domains in the proCatC dimer complex allows this order of cleavages to be understood. The missense mutation Leu172Pro within the propeptide region associated with the PapillonâLefĂšvre and HaimâMunk syndrome altered the proform stability as well as the maturation of the recombinant Leu172Pro proform