Current Pharmaceutical Design - Volume 19, Issue 6, 2013

Human neutrophil proteinase 3 (PR3) and elastase (HNE) are homologous serine proteinases involved in the proteolytic events associated with inflammation and infection. Their close structural and functional resemblance makes it difficult to understand their respective biological functions. Thus, all natural inhibitors of PR3 identified to date preferentially target HNE, and only recently have inhibitors that target PR3 selectivel Read More

The HtrA proteases degrade damaged proteins and thus control the quality of proteins and protect cells against the consequences of various stresses; they also recognize specific protein substrates and in this way participate in regulation of many pathways. In many pathogenic bacteria strains lacking the HtrA function lose virulence or their virulence is decreased. This is due to an increased vulnerability of bacteria to stre Read More

The giant proteolytic factory called the proteasome came a long way from a biochemical curio to a major regulator of cellular physiology and a renowned drug target within the ubiquitin proteasome pathway (UPP). Thanks to availability of highly specific inhibitors of the proteasome, in less than twenty years it was possible to identify major transcription factors, cyclins, and products of oncogenes as crucial substrates for the Read More

Processing of antigens within antigen presenting cells (APCs) is necessary for an immune response. Two pathways exist to present antigens to T cells: the major histocompatibility complex class I (MHC I) pathway to activate cytotoxic T cells (CTLs) and the MHC II route to stimulate T helper cells (Ths). Prior to efficient antigen presentation to MHC II, antigens have to be proteolytically degraded by proteases, the cathepsins, in Read More

Neuropeptides play crucial, mediatory roles in many processes that occur in both CNS and PNS. The commonly accepted dogma for the release of bioactive peptides involves cleavage of inactive precursor by sequential action of proteinases recognizing dibasic stretches, followed by truncation of C-terminal Arg/Lys by the carboxypeptidase-like enzyme(s). Dynorphin convertases play an important role in CNS by regulating dynor Read More

Matriptase-2 is a cell surface serine protease with a modular structure. The exploration of its function in iron homeostasis was of significance for the understanding of the regulation of hepcidin expression, the master protein in iron control. Mutations in matriptase- 2 cause iron-refractory iron deficiency anemia (IRIDA), an iron deficiency disorder where the level of hepcidin is inappropriately high. Matriptase-2 controls hepcidin Read More

Proteolysis is doubtlessly the most widespread mechanism of biological regulation. By controlling protein synthesis, turnover and activity, it is involved in fundamental physiological processes including apoptosis, cell differentiation, growth and signaling, fertilization, immune response, blood coagulation and digestion. Yet, uncontrolled proteolysis can be harmful for organisms, causing - amongst others - such diseases as canc Read More

The deregulated proteolysis is associated with various diseases in humans. Proteases are commonly regarded as the therapeutic targets. Almost one-third of all proteolytic enzymes in humans are serine proteases. This work provides a brief characteristic of the proteinaceous natural inhibitors, mostly of serine proteases. The examples of some classical and recently identified canonical and noncanonical inhibitors as w Read More

Matrix metalloproteinases (MMPs) are either secreted or membrane-bound proteases, capable to degrade extracellular matrix (ECM) proteins as well as a large number of non-ECM proteins, such as growth factors, cytokines, chemokines, cell surface receptors, serine proteinase inhibitors and other MMPs. MMPs play major physiological roles in reproduction, growth, development, angiogenesis, immune response, wound healing Read More

Pathogenic bacteria have evolved multiple mechanisms aimed to evade host defenses. This review summarizes selected examples of how bacteria utilize proteolytic enzymes to efficiently establish and spread infection systemically. First, the role of proteases in intracellular survival and persistence – the primary means used by bacteria to endure phagocytosis and/or avoid the vigilance of the immune system – is discusse Read More

Mast cells are critical effectors in inflammatory diseases, including cardiovascular and metabolic diseases and their associated complications. These cells exert their physiological and pathological activities by releasing granules containing histamine, cytokines, chemokines, and proteases, including mast cell-specific chymases and tryptases. Several recent human and animal studies have shown direct or indirect participatio Read More

In order to productively infect a host, viruses must enter the cell and force host cell replication mechanisms to produce new infectious virus particles. The success of this process unfortunately results in disease progression and, in the case of infection with many viral species, may cause mortality. The discoveries of Louis Pasteur and Edward Jenner led to one of the greatest advances in modern medicine - the developme Read More

α-Aminoalkylphosphonate diaryl esters are potent, irreversible, and highly selective site-directed inhibitors of serine proteases. The structure of the phosphonate group resembles the transition state observed during a peptide bond hydrolysis and therefore phosphonates are referred as transition state analogues. They react with the hydroxyl group of the active site serine residue leading to formation of a stable enzyme-inhibitor co Read More