Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Preparation, in vitro release, in vivo absorption and biocompatibility studies of insulin-loaded microspheres in rabbits

The purpose of this study was to develop a single-dose insulin delivery system based on poly (lactide-co-glycolide) (PLGA) microspheres to provide basal insulin level for a prolonged period. Insulin-loaded PLGA microspheres were prepared by water-in-oil-in-water double emulsion (batch A) and solid-in0oil-in-water emulsion (batch B) methods. Microspheres were characterized for physical characteristics and in vitro release. In vivo absorption of insulin and biocompatibility of insulin-loaded PLGA microspheres were performed in diabetic New Zealand white rabbits. Light and transmission electron microscopy were performed on the skin tissues excised from microspheres injected sites in order to study the biocompatibility. The burst release of insulin was high (47%) from batch B and low (5%) from batch A. Therefore, we mixed microspheres of batch A and B in ratio of 3∶ w/w, which produced desirable in vitro release profile. In vivo absorption study showed that insulin-loaded microspheres provided a serum insulin level of 20–40 μU/ml up to 40 days. Biocompatibility study provided evidence of normal inflammatory and foreign body reactions, which were characterized by the presence of macrophages, fibroblasts and foreign body giant cells. Neither necrosis nor tissue damage was identified. At the end of 12 weeks, no distinct histological differences were observed in comparison to the control tissue samples. In conclusion, insulin-loaded PLGA microspheres controlled the in vivo absorption of insulin to maintain the basal insulin level for longer period and the delivery system was biocompatible

Anti-C1q autoantibodies in murine lupus nephritis

Autoantibodies against C1q can be found in the circulation of patients with several autoimmune diseases including systemic lupus erythematosus (SLE). In SLE there is an association between the occurrence of these antibodies and renal involvement. How anti-C1q autoantibodies contribute to renal disease is currently unknown. Cohorts of MRL-lpr mice, which are known to develop age-dependent SLE-like disease, were used to study the relationship between levels of anti-C1q autoantibodies and renal disease. We collected serum, urine and renal tissue and analysed autoantibodies, complement levels and renal deposition as well as renal function. At 2 months of age all mice already had elevated levels of anti-C1q autoantibodies, and elution of kidneys revealed the presence of these antibodies in renal immune deposits in MRL-lpr mice and not in control MRL(+/+) mice. In conclusion, anti-C1q antibodies are already present in serum and immune deposits of the kidney early in life and therefore can play a role in nephritis during experimental SLE-like disease in mice

Experimental lupus nephritis in severe combined immunodeficient (SCID) mice: remodelling of the glomerular lesions by bystander IgM antibodies

MRL/Mp-lpr/lpr (MRL/lpr) mice develop glomerular lesions with regular variations in their histopathological manifestations, similar to those in lupus nephritis. These lesions are mainly either cell-proliferative or wire loop-like and are associated with glomerular deposits of immunoglobulins, most frequently IgG and IgM. We previously established a nephritogenic IgG3-producing hybridoma clone, B1, from an MRL/lpr mouse, which induces only a ‘wire loop-like’ type of glomerular lesion when injected into SCID mice. Injection of SCID mice with an anti-trinitrophenyl IgM antibody-producing hybridoma clone, Sp6, following injection of the B1 clone, however, resulted in the development of a ‘cell-proliferative’ type of glomerular lesion, associated with an accumulation of both antibodies in glomeruli. This accumulation occurred even though Sp6 IgM antibodies did not react with B1 IgG3 antibodies and vice versa. A mutant clone of Sp6, T/13μE/3.1, which produces antibodies deficient in C1q binding, produced a similar effect as that of the Sp6 clone, i.e. ‘cell-proliferative’ lesions. Again the B1 antibodies did not react with T/13μE/3.1-IgM antibodies and vice versa. We therefore conclude that bystander IgM antibodies contribute to the remodelling of glomerular lesions in situ, following glomerular injury by the nephritogenic antibodies

Cryogels with Affinity Ligands as Tools in Protein Purification

Affinity chromatography is one of the well-known separation techniques especially if high purity is desired. Introducing ligands on monolithic structure gives the possibility for purifying complex media such as plasma and crude extract. This chapter is focusing on the preparation of cryogels as monolithic column and immobilization of concanavalin A on its surface as ligand for capturing the glycoprotein horseradish peroxidase