Vitamin D3 promotes oligodendrogenesis and modulates synucleinopathy in lead-induced nigral pars compacta neurotoxicity in rats.

BACKGROUND: Lead-induced neurotoxicity was marked with locomotor and Parkinsonian-like changes. Oligodendrocytes and synucleinopathy were signed to in the pathophysiology of some neurodegenerative diseases. Vitamin D3's (D3) role in substantia nigra pars compacta (SNpc) disorders is debated between neuroscientists. The aim of the study was to investigate lead-induced SNpc neurotoxic changes and explore the possible neuroprotective role of D3 and the possible involvement of oligodendrocytes and α-synuclein. MATERIALS AND METHODS: This study included 40 adult Wistar rats assigned into four equal groups: control, lead (Pb) (in drinking water, 1,000 mg/L), Pb + D3 (D3 injection, 1,000 IU/kg IM; 3 days/week), and D3. After 8 weeks, the rats were sacrificed, and their midbrain underwent biochemical and immunoblotting analysis. Midbrain paraffin blocks were stained for histological and immunohistochemical assessment. RESULTS: Lead (Pb) had increased significantly (p < 0.05) nigral α-synuclein and caspase-11 by immunoblotting analysis. Histologically, it induced neurodegeneration in SNpc and significantly decreased neuronal cell density by cresyl violet staining. Pb also significantly reduced SNpc tyrosine hydroxylase immunoreaction, significantly elevated glial fibrillatory acid protein (GFAP) and α-synuclein immunoreaction associated with a mild but significant increase in caspase-3. In the Pb + D3 group, all the previous deleterious changes were significantly alleviated in addition to significant upregulation of anti-oligodendrocytes immunoexpression. CONCLUSIONS: Lead (Pb) may induce SNpc neurotoxicity presumably via activation of caspase-11 and α-synuclein. D3 may modulate this neurotoxicity probably through an oligodendrogenic effect.

Patients with tumour necrosis factor (TNF) receptor-associated periodic syndrome (TRAPS) are hypersensitive to Toll-like receptor 9 stimulation.

Tumour necrosis factor receptor-associated periodic syndrome (TRAPS) is a hereditary autoinflammatory disorder characterized by recurrent episodes of fever and inflammation. It is associated with autosomal dominant mutations in TNFRSF1A, which encodes tumour necrosis factor receptor 1 (TNF-R1). Our aim was to understand the influence of TRAPS mutations on the response to stimulation of the pattern recognition Toll-like receptor (TLR)-9. Peripheral blood mononuclear cells (PBMCs) and serum were isolated from TRAPS patients and healthy controls: serum levels of 15 proinflammatory cytokines were measured to assess the initial inflammatory status. Interleukin (IL)-1ß, IL-6, IL-8, IL-17, IL-22, tumour necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), interferon (IFN)-γ, monocyte chemoattractant protein 1 (MCP-1) and transforming growth factor (TGF)-ß were significantly elevated in TRAPS patients' sera, consistent with constitutive inflammation. Stimulation of PBMCs with TLR-9 ligand (ODN2006) triggered significantly greater up-regulation of proinflammatory signalling intermediates [TNF receptor-associated factor (TRAF 3), IL-1 receptor-associated kinase-like 2 (IRAK2), Toll interacting protein (TOLLIP), TRAF6, phosphorylated transforming growth factor-ß-activated kinase 1 (pTAK), transforming growth factor-ß-activated kinase-binding protein 2 (TAB2), phosphorylated TAK 2 (pTAB2), IFN-regulatory factor 7 (IRF7), receptor interacting protein (RIP), nuclear factor kappa B (NF-κB) p65, phosphorylated NF-κB p65 (pNF-κB p65) and mitogen-activated protein kinase kinase (MEK1/2)] in TRAPS patients' PBMCs. This up-regulation of proinflammatory signalling intermediates and raised serum cytokines occurred despite concurrent anakinra treatment and no overt clinical symptoms at time of sampling. These novel findings further demonstrate the wide-ranging nature of the dysregulation of innate immune responses underlying the pathology of TRAPS and highlights the need for novel pathway-specific therapeutic treatments for this disease.

Protective antibodies against Clostridium difficile are present in intravenous immunoglobulin and are retained in humans following its administration.

The prevalence of serum antibodies against Clostridium difficile (CD) toxins A and B in healthy populations have prompted interest in evaluating the therapeutic activity of intravenous immunoglobulin (IVIg) in individuals experiencing severe or recurrent C. difficile infection (CDI). Despite some promising case reports, a definitive clinical role for IVIg in CDI remains unclear. Contradictory results may be attributed to a lack of consensus regarding optimal dose, timing of administration and patient selection as well as variability in specific antibody content between commercial preparations. The purpose of this study was to investigate retrospectively the efficacy of three commercial preparations of IVIg for treating severe or recurrent CDI. In subsequent mechanistic studies using protein microarray and toxin neutralization assays, all IVIg preparations were analysed for specific binding and neutralizing antibodies (NAb) to CD antigens in vitro and the presence of anti-toxin NAbs in vivo following IVIg infusion. A therapeutic response to IVIg was observed in 41% (10 of 17) of the CDI patients. Significant variability in multi-isotype specific antibodies to a 7-plex panel of CD antigens and toxin neutralization efficacies were observed between IVIg preparations and also in patient sera before and after IVIg administration. These results extend our current understanding of population immunity to CD and support the inclusion of surface layer proteins and binary toxin antigens in CD vaccines. Future strategies could enhance IVIg treatment response rates by using protein microarray to preselect donor plasma/serum with the highest levels of anti-CD antibodies and/or anti-toxin neutralizing capacities prior to fractionation.

Association of antibodies to hepatitis C virus glycoproteins 1 and 2 (anti-E1E2) with HCV disease.

Hepatitis C virus (HCV) causes acute and chronic liver diseases in humans. Its two envelope glycoproteins, E1 and E2, provide a target for host immune recognition. HCV genotypes are classified into six genetic groups. To study the role of anti-HCV E1 and E2 (anti-E1E2) in HCV disease, the correlation between antibody level and viral load, genotype, disease severity and response to treatment was investigated. The levels of antibodies to HCV glycoproteins E1 and E2 antibodies were evaluated in 230 sera of patients with chronic hepatitis C by enzyme-linked immunosorbent assay. The antigens used were recombinant HCV glycoproteins derived from genotype 1 (H77c) and genotype 3 (UKN3A1.28). Seroreactivity was greater when sera were tested against antigen derived from their homologous genotype than against heterologous antigen. Reactivity against UKN3A1.28 in sera from patients infected with genotype 3 was significantly higher than corresponding reactivity between patients infected with genotype 1 and H77c. The seroreactivity was inversely proportional to the viral load and to the degree of liver fibrosis. The pre-treatment level of anti-E1E2 was higher in sustained responders to combination therapy. These results demonstrate that seroreactivity against E1E2 depends upon the genotypic origin of the E1E2 antigens and the infecting genotype, and suggest a possible protective effect of anti-E1E2 against disease progression.

Influence of protein malnutrition on teratogenicity of acetylsalicylic acid in rats.

The effect of protein malnutrition (PM) on the embryotoxicity and teratogenicity of aspirin in rats has been studied. Protein malnourishment was produced from Days 7 to 21 of gestation by limiting the casein content of the diet to 5% in comparison to 20% for the normal animals. Six dose levels of aspirin (50-175 mg kg-1) were administered p.o. from Days 8 to 11 of pregnancy. Aspirin from 75 mg kg-1 d-1 induced growth retardation, embryolethality and teratogenicity, as shown by external, skeletal and visceral malformations. All these effects were potentiated by protein malnutrition.