Soluble ICAM-1: a marker of vascular inflammation and lifestyle

The circulating form of a membrane-bound intercellular adhesion molecule-1 (ICAM-1), has been the source of recent debate as a candidate marker of vascular inflammation in atherosclerosis and myocardial infarction, although its increased levels were also observed in other diseases affecting the cardiovascular system, such as myocarditis, inflammatory cardiomyopathy and heart failure per se. Faulty dietary habits, a sedentary mode of life, smoking, and alcohol abuse, are factors which at least in part contribute to atherosclerosis. This paper describes the responses of sICAM-1 levels to nutrients, physical activity, smoke exposure and alcohol consumption.     

Caspase inhibition: a potential therapeutic strategy in neurological diseases

Caspases are intracellular proteases that participate in apoptotic pathways in mammalian cells, including neurons. Here we review evidence that caspase inhibition, through pharmacological or molecular means, may inhibit neuronal cell death in a number of in vitro and in vivo models of neurological disease. It has recently become clear that, at least in most cell culture models, caspase inhibition offers only transient protection, and that a caspase-independent death eventually occurs. This may be due to irreversible caspase-independent alterations at the level of the mitochondria. Despite concerns that targeting caspases alone may prove insufficient to truly reverse the effects of various death stimuli, in vivo studies indicate that caspase inhibition promotes survival and functional outcome in a variety of neurological disease models. In addition, studies of human post-mortem material suggest that caspases are activated in certain human neurological diseases. Caspase inhibition may therefore provide a novel strategy for the treatment of such disorders. Caspases, through the generation of toxic fragments of critical protein substrates, may also be involved in earlier steps of neuronal dysfunction, such as protein aggregation in Huntington's and Alzheimer's disease, and therefore caspase inhibition may be of additional value in the treatment of these particular disorders.     

Endocannabinoid, anandamide in gingival tissue regulates the periodontal inflammation through NF-kappaB pathway inhibition

Anandamide (AEA) exhibits anti-inflammatory effects. However, its role in the periodontal field remains unknown. Here, we found that gingival crevicular fluid contained a detectable level of AEA. The cannabinoid receptors CB1 and CB2 were expressed by human gingival fibroblasts (HGFs), and markedly upregulated under pathological conditions. AEA significantly reduced the production of pro-inflammatory mediators (IL-6, IL-8 and MCP-1) induced by Porphyromonas gingivalis LPS in HGFs, and this effect was attenuated by AM251 and SR144528, selective antagonists of CB1 and CB2, respectively. Moreover, AEA completely blocked LPS-triggered NF-kappaB activation, implying that AEA may regulate hyperinflammatory reactions in periodontitis.     

TriVax-HPV: an improved peptide-based therapeutic vaccination strategy against human papillomavirus-induced cancers

Background

Therapeutic vaccines for cancer are an attractive alternative to conventional therapies, since the later result in serious adverse effects and in most cases are not effective against advanced disease. Human papillomavirus (HPV) is responsible for several malignancies such as cervical carcinoma. Vaccines targeting oncogenic viral proteins like HPV16-E6 and HPV16-E7 are ideal candidates to elicit strong immune responses without generating autoimmunity because: (1) these products are not expressed in normal cells and (2) their expression is required to maintain the malignant phenotype. Our group has developed peptide vaccination strategy called TriVax, which is effective in generating vast numbers of antigen-specific T cells in mice capable of persisting for long time periods.

Materials and methods

We have used two HPV-induced mouse cancer models (TC-1 and C3.43) to evaluate the immunogenicity and therapeutic efficacy of TriVax prepared with the immunodominant CD8 T-cell epitope HPV16-E7_49-57, mixed with poly-IC adjuvant and costimulatory anti-CD40 antibodies.

Results

TriVax using HPV16-E7_49-57 induced large and persistent T-cell responses that were therapeutically effective against established HPV16-E7 expressing tumors. In most cases, TriVax was successful in attaining complete rejections of 6–11-day established tumors. In addition, TriVax induced long-term immunological memory, which prevented tumor recurrences. The anti-tumor effects of TriVax were independent of NK and CD4 T cells and, surprisingly, did not rely to a great extent on type-I or type-II interferon.

Conclusions

These findings indicate that the TriVax strategy is an appealing immunotherapeutic approach for the treatment of established viral-induced tumors. We believe that these studies may help to launch more effective and less invasive therapeutic vaccines for HPV-mediated malignancies.     

ICAM-1 in acute myocardial infarction: a potential therapeutic target

Current treatments for AMI centre on prompt restoration of epicardial coronary blood flow. Despite improvements, AMI is still associated with significant morbidity and mortality. Novel approaches are therefore keenly sought. Intercellular adhesion molecule-1 (ICAM-1, CD54) is a member of the immunoglobulin superfamily. It is implicated in neutrophil and monocyte-endothelial cell adhesion, processes contributing to myocardial neutrophil infiltration and microvascular coronary slow flow, both viewed as important to the pathophysiologic responses in AMI. ICAM-1 would therefore appear an important potential therapeutic target in this context, and is the subject of this review.     

Antisense-mediated exon skipping: a versatile tool with therapeutic and research applications

Antisense-mediated modulation of splicing is one of the few fields where antisense oligonucleotides (AONs) have been able to live up to their expectations. In this approach, AONs are implemented to restore cryptic splicing, to change levels of alternatively spliced genes, or, in case of Duchenne muscular dystrophy (DMD), to skip an exon in order to restore a disrupted reading frame. The latter allows the generation of internally deleted, but largely functional, dystrophin proteins and would convert a severe DMD into a milder Becker muscular dystrophy phenotype. In fact, exon skipping is currently one of the most promising therapeutic tools for DMD, and a successful first-in-man trial has recently been completed. In this review the applicability of exon skipping for DMD and other diseases is described. For DMD AONs have been designed for numerous exons, which has given us insight into their mode of action, splicing in general, and splicing of the DMD gene in particular. In addition, retrospective analysis resulted in guidelines for AON design for DMD and most likely other genes as well. This knowledge allows us to optimize therapeutic exon skipping, but also opens up a range of other applications for the exon skipping approach.     

Role of inflammation and oxidative stress in tissue damage associated with cystic fibrosis: CAPE as a future therapeutic strategy

Molecular and Cellular Biochemistry - Cystic fibrosis (CF) is an autosomal recessive disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, responsible...     

Kynurenine pathway inhibition as a therapeutic strategy for neuroprotection

The oxidative pathway for the metabolism of tryptophan along the kynurenine pathway generates quinolinic acid, an agonist at N-methyl-D-aspartate receptors, as well as kynurenic acid which is an antagonist at glutamate and nicotinic receptors. The pathway has become recognized as a key player in the mechanisms of neuronal damage and neurodegenerative disorders. As a result, manipulation of the pathway, so that the balance between the levels of components of the pathway can be modified, has become an attractive target for the development of pharmacological agents with the potential to treat those disorders. This review summarizes some of the relevant background information on the pathway itself before identifying some of the chemical strategies for its modification, with examples of their successful application in animal models of infection, stroke, traumatic brain damage, cerebral malaria and cerebral trypanosomiasis.     

Cerivastatin suppresses lipopolysaccharide-induced ICAM-1 expression through inhibition of Rho GTPase in BAEC

Both LIM15/DMC1 and RAD51 are thought to be essential for meiosis in which homologous chromosomes pair and recombine. The primary purpose of the present study was to investigate the homotypic and heterotypic interactions among their terminal domains. We prepared cDNAs and recombinant proteins of the full-length, N-terminal, and the C-terminal domains of LIM15/DMC1 (CoLIM15) and RAD51 (CoRAD51) from the basidiomycete Coprinus cinereus. In both two-hybrid assay in vivo and pull-down assay in vitro, either CoLim15 or CoRad51 interacted homotypically between the C-terminal domains, respectively, but no heterotypic interaction was observed between CoLim15 and CoRad51. The N-terminal domain of CoLim15 bound to ssDNA and dsDNA, while the C-terminal domain of CoRad51 appeared to interact weakly with ssDNA. Based on these results, the interaction among the strand-exchange proteins and meiosis was discussed.     

TOP1 inhibition therapy protects against SARS-CoV-2-induced lethal inflammation

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ICAM-1-dependent fibroblast-lymphocyte adhesion: discordance between surface expression and function of ICAM-1

We have previously reported that stimulation of human fibroblasts (FB) with interferon-gamma (IFN-gamma) leads to their increased adhesiveness for resting peripheral blood T lymphocytes. With the use of blocking monoclonal antibodies, we determined that intercellular adhesion molecule-1 (ICAM-1) and its T cell ligand, lymphocyte function-associated antigen-1 (LFA-1) are the major, if not only ligands involved in this system. Using an ELISA, we have confirmed earlier reported observations that IFN-gamma induces an increase of ICAM-1 expression on the surface of FB suggesting that this increase mediates lymphocyte adhesion. However, we show that treatment of FB with IL-1, while leading to comparable increases in ICAM-1 synthesis and expression, failed to induce increased adhesion. In contrast, treatment of fibroblasts with the phorbol ester, TPA, stimulated ICAM-1-dependent adhesion without an increase in ICAM-1 surface expression. This suggested that the detection of ICAM-1 by monoclonal antibody techniques may not always correlate with its functional capabilities. The contrasting effects of IFN-gamma and IL-1 on ICAM-1-dependent FB adhesion suggest that qualitative as well as quantitative alterations of the ICAM-1 molecule may regulate ligand interaction.     

Beta-synuclein inhibits formation of alpha-synuclein protofibrils: a possible therapeutic strategy against Parkinson's disease

Parkinson's disease (PD) is an age-associated and progressive movement disorder that is characterized by dopaminergic neuronal loss in the substantia nigra and, at autopsy, by fibrillar alpha-synuclein inclusions, or Lewy bodies. Despite the qualitative correlation between alpha-synuclein fibrils and disease, in vitro biophysical studies strongly suggest that prefibrillar alpha-synuclein oligomers, or protofibrils, are pathogenic. Consistent with this proposal, transgenic mice that express human alpha-synuclein develop a Parkinsonian movement disorder concurrent with nonfibrillar alpha-synuclein inclusions and the loss of dopaminergic terminii. Double-transgenic progeny of these mice that also express human beta-synuclein, a homologue of alpha-synuclein, show significant amelioration of all three phenotypes. We demonstrate here that beta- and gamma-synuclein (a third homologue that is expressed primarily in peripheral neurons) are natively unfolded in monomeric form, but structured in protofibrillar form. Beta-synuclein protofibrils do not bind to or permeabilize synthetic vesicles, unlike protofibrils comprising alpha-synuclein or gamma-synuclein. Significantly, beta-synuclein inhibits the generation of A53T alpha-synuclein protofibrils and fibrils. This finding provides a rationale for the phenotype of the double-transgenic mice and suggests a therapeutic strategy for PD.     

Retinoic acid potentiates TNF-alpha-induced ICAM-1 expression in normal human epidermal keratinocytes

ICAM-1 protein in keratinocytes is thought to contribute to cutaneous inflammatory reactions. Its induction depends-among others-on cytokines such as TNF-alpha, IFN-gamma, IL-1 or on retinoic acid (RA), a key regulator of epidermal homeostasis. We investigated the effect of treatments with TNF-alpha, RA or their combination on ICAM-1 expression on proliferative or differentiating keratinocytes over an 8 day culture period. Basal ICAM-1 levels were undetectable at low (30 microM) and standard (88 microM) Ca2+ and RA alone did not induce ICAM-1. However, at high Ca2+ (1500 microM), ICAM-1 levels were augmented in response to RA-treatment. TNF-alpha induced a transient ICAM-1 increase in NHK, which reached peak-levels 2-4 days post cytokine stimulus. RA potentiated the TNF-alpha-induced ICAM-1 response in all Ca2+-concentrations. This potentiating effect of RA was confirmed at the mRNA level. In summary, our results establish retinoic acid as an enhancer of TNF-alpha-induced ICAM-1 levels in NHK.     

Poly(ADP-ribose) polymerase-1 inhibition protects the brain against systemic inflammation

Poly(ADP-ribose) polymerase-1 (PARP-1) is involved in DNA repair, but its overactivation can induce cell death. Our aim was to investigate the role of PARP-1 in activation of programmed cell death processes in the brain during systemic inflammation.

Our data indicated that lipopolysaccharide (1 mg/kg b.w., i.p.)-evoked systemic inflammation enhanced PARP-1 activity in the mouse brain, leading to the lowering of β-NAD⁺ concentration, to translocation of apoptosis inducing factor from mitochondria to the nucleus, and to enhanced lipid peroxidation. Inhibitor of PARP-1, 3-aminobenzamide (30 mg/kg b.w., i.p.), protected the brain against prooxidative and cell death processes, suggesting involvement of PARP-1 in systemic inflammation-related processes in the brain.