myelin-basic-protein and 4-hydroxy-2-nonenal

Aroclor 1254 is a widespread toxic compound of Polychlorinated Biphenyls (PCBs), which can create significant nervous problems. No remedies have been found to date. The aim of this study was to reveal the damage that occurs in the central nervous system of rat pups exposed to Aroclor 1254 in the prenatal period and to show the inhibiting effect of curcumin, which is a strong anti-oxidant and neuroprotective substance.. The study established 3 groups of adult female and male Wistar albino rats. The rats were mated within these groups and the offspring rats were evaluated within the group given Aroclor 1254 only (n=10) and the group was given both Aroclor 1254 and curcumin (n=10) and the control group (n=10). The groups were compared in respect of pathomorphological damage. The immunohistochemical evaluation was made of 8-hydroxdeoxyguanosine (8-OHdG), 4-hydroxynoneal (4HNE), myelin basic protein (MBP) expressions and TUNEL reaction. The biochemical evaluation was made of the changes in the TAS-TOS and Neuron Specific Enolase (NSE) levels. Damage was seen to have been reduced with curcumin in the 8OHdG and TUNEL reactions, especially in the forebrain and the midbrain, although the dosage applied did not significantly change TAS and TOS levels. Consequently, it was understood that Aroclor 1254 caused damage in the central nervous system of the pup in the prenatal period, and curcumin reduced these negative effects, particularly in the forebrain and the midbrain.. It was concluded that curcumin could be a potential neuroprotective agent and would be more effective at higher doses.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Antioxidants; Brain; Chlorodiphenyl (54% Chlorine); Curcumin; Deoxyguanosine; Female; Immunohistochemistry; Male; Myelin Basic Protein; Neuroprotective Agents; Oxidants; Phosphopyruvate Hydratase; Pregnancy; Prenatal Exposure Delayed Effects; Rats

Traumatic brain injury (TBI) encompasses a broad range of injury mechanisms and severity. A detailed determination of TBI severity can be a complex challenge, with current clinical tools sometimes insufficient to tailor a clinical response to a spectrum of patient needs. Blood biomarkers of TBI may supplement clinical assessments but currently available biomarkers have limited sensitivity and specificity. While oxidative stress is known to feature in damage mechanisms following TBI, investigation of blood biomarkers of oxidative stress has been limited. This exploratory pilot study of a subset of 18 trauma patients with TBI of varying severity, quantifies circulating concentrations of the structural damage indicators S100b, and myelin basic protein (MBP), and the biomarkers of oxidative stress hydroxynonenal (HNE), malondialdehyde (MDA), carboxy-methyl-lysine (CML), and 8-hydroxy-2'-deoxy-guanosine (8-OHDG). Significant increases in circulating S100b, MBP, and HNE were observed in TBI patient samples compared to 8 uninjured controls, and there was a significant decrease in CML. This small exploratory study supports the current literature on S100b and MBP elevation in TBI, and reveals potential for the use of peripheral oxidative stress markers to assist in determination of TBI severity. Further investigation is required to validate results and confirm trends.

Topics: Adult; Aldehydes; Biomarkers; Brain Injuries, Traumatic; Female; Humans; Male; Myelin Basic Protein; Oxidative Stress; Pilot Projects; Prospective Studies; S100 Calcium Binding Protein beta Subunit; Treatment Outcome

Cerebellar dysfunction is a significant contributor to disability in multiple sclerosis (MS). Both white matter (WM) and grey matter (GM) injury occurs within MS cerebellum and, within GM, demyelination, inflammatory cell infiltration and neuronal injury contribute to on-going pathology. The precise nature of cerebellar GM injury is, however, unknown. Oxidative stress pathways with ultimate lipid peroxidation and cell membrane injury occur extensively in MS and the purpose of this study was to investigate these processes in MS cerebellar GM. Post-mortem human cerebellar GM from MS and control subjects was analysed immunohistochemically, followed by semi-quantitative analysis of markers of cellular injury, lipid peroxidation and anti-oxidant enzyme expression. We have shown evidence for reduction in myelin and neuronal markers in MS GM, coupled to an increase in expression of a microglial marker. We also show that the lipid peroxidation product 4-hydroxynonenal co-localises with myelin and its levels negatively correlate to myelin basic protein levels. Furthermore, superoxide dismutase (SOD1 and 2) enzymes, localised within cerebellar neurons, are up-regulated, yet the activation of subsequent enzymes responsible for the detoxification of hydrogen peroxide, catalase and glutathione peroxidase are relatively deficient. These studies provide evidence for oxidative injury in MS cerebellar GM and further help define disease mechanisms within the MS brain.

Topics: Adult; Aged; Aged, 80 and over; Aldehydes; Cerebellum; Female; Gray Matter; Humans; Lipid Peroxidation; Male; Microglia; Middle Aged; Multiple Sclerosis; Myelin Basic Protein; Myelin Sheath; Neurons; Oxidative Stress; RNA, Messenger; Superoxide Dismutase; Superoxide Dismutase-1; White Matter

We hypothesized that heme oxygenase (HO)-1, the inducible form of HO, represents an important defense against early oxidative injury in the traumatized spinal cord by stabilizing the blood-spinal cord barrier and limiting the infiltration of leukocytes. To test this hypothesis, we first examined the immunoexpression of HO-1 and compared barrier permeability and leukocyte infiltration in spinal cord-injured HO-1-deficient (+/-) and wild-type (WT, +/+) mice. Heme oxygenase was expressed in both endothelial cells and glia of the injured cord. Barrier disruption to luciferase and infiltration of neutrophils were significantly greater in the HO-1+/- than WT mice at 24 h postinjury (P

Topics: Aldehydes; Animals; Blood Vessels; Blotting, Western; Brain; Enzyme Induction; Heme Oxygenase (Decyclizing); Heme Oxygenase-1; Immunohistochemistry; Inflammation; Male; Malondialdehyde; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin Basic Protein; Neutrophil Infiltration; Oxidative Stress; Spinal Cord; Spinal Cord Injuries

NFE2-related factor 2 (Nrf2), an oxidant-activated CNC bZip transcription factor, has been implicated in defense against oxidative stress and chemical insults in a range of cell and tissue types, including the central nervous system. Here, we report that deletion of the Nrf2 gene in mice caused vacuolar (spongiform) leukoencephalopathy with widespread astrogliosis. The leukoencephalopathy was present in all Nrf2-null mice more than 10 months of age, was characterized by vacuolar degeneration involving all major brain regions, and was most apparent in the white tracts of the cerebellum and pons. Vacuolar degeneration in white tracts was attributable to myelin unwinding and intramyelinic cysts, and double-label immunofluorescence for 4-hydroxy-2-nonenal and myelin basic protein localized free-radical-induced oxidative damage to the myelin sheath. Moreover, the brains of Nrf2-null mice exhibited widespread astrocyte activation with profusion of glial fibrillary acidic protein-immunoreactive glial processes. The study uncovered a possible physiological role for Nrf2 in maintaining central nervous system myelin. If this role is confirmed, it may suggest new approaches to treating genetically and chemically induced myelin degenerative diseases.

Topics: Aldehydes; Animals; Astrocytes; Autoimmune Diseases; Cysteine Proteinase Inhibitors; Mice; Mice, Knockout; Myelin Basic Protein; Neurodegenerative Diseases; NF-E2-Related Factor 2; Vacuoles

The lipid peroxidation product 4-hydroxy-2-nonenal (HNE) is generated as a consequence of oxidative stress and can readily react with nucleophilic sites of proteins (e.g., histidine residues), mainly via a Michael addition. The formation of such lipid-protein conjugates can alter protein properties and biological functions, thus leading to highly deleterious effects. The present work describes a rapid (very limited sample preparation) and sensitive (low-femtomole range) procedure to identify HNE-modified peptides (Michael adducts) within unfractionated tryptic digests. The protocol involves the formation of dinitrophenylhydrazones of the Michael adducts, when using 2,4-dinitrophenylhydrazine as reactive matrix, followed by analysis using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS). The hydrazone derivatives present high desorption/ionization yield and can thus be preferentially detected compared to unmodified peptides. The MALDI mass spectrum obtained is therefore drastically different from the one obtained with the classical 4-hydroxy-alpha-cyanocinnamic acid matrix. Moreover, the presence of HNE, or more generally speaking carbonylated peptides, could be highlighted by 180 mass units differences (corresponding to the dinitrophenylhydrazone moiety) between these two MALDI mass spectra. Further information (e.g., localization/identification of the modified residues, peptide sequences) could be obtained by performing MALDI postsource decay (or electrospray) MS/MS experiments on the ions of interest.

Topics: Aldehydes; Amino Acid Sequence; Animals; Apoproteins; Horses; Molecular Sequence Data; Myelin Basic Protein; Myoglobin; Peptide Fragments; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

White matter of the neonatal brain is highly sensitive to hypoxic-ischemic insult. The susceptibility of premature oligodendrocytes (OLs) to free radicals (FRs) produced during hypoxia-ischemia (HI) has been proposed as one of the mechanisms involved. To test this hypothesis, and to further investigate if the FR scavenger alpha-phenyl-N-tert-butyl-nitrone (PBN) attenuates hypoxic-ischemic white matter damage (WMD), postnatal day 4 (P4) SD rats were subjected to bilateral common carotid artery ligation (BCAL), followed by 8% oxygen exposure for 20 min. Pathological changes were evaluated on P6 and P9, 2 and 5 days after the HI insult. HI caused severe WMD including rarefaction, necrosis and cavity formation in the corpus callosum, external and internal capsule areas. OL injury was evidenced by degeneration of O4 positive OLs on P6. Disrupted myelination was verified by decreased immunostaining of myelin basic protein (MBP) on P9. Axonal injury was demonstrated by increased amyloid precursor protein (APP) immunostaining on both P6 and P9. Two lipid peroxidation end products, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), showed a one-fold elevation within 1-24 h following HI. 4-HNE immunostaining was found to specifically localize in the white matter area. Furthermore, pyknotic O4+ OLs were double-labeled with 4-HNE. These findings suggest that FRs are involved in the pathogenesis of neonatal WMD. PBN (100 mg/kg, i.p.) treatment alleviated the pathological changes of WMD following HI. It improved the survival of O4 positive OLs, attenuated hypomyelination and reduced axonal damage. PBN treatment also decreased the brain concentration of MDA/4-HNE and positive 4-HNE staining in the white matter area. These findings indicate that in the current WMD model, PBN protects both OLs and axons, the two main components in the white matter, from neonatal HI insult. FR scavenging appears to be the primary mechanism underlying its neuroprotective effect.

Topics: Age Factors; Aldehydes; Amyloid beta-Peptides; Analysis of Variance; Animals; Animals, Newborn; Antigens, Differentiation; Brain; Cell Count; Cell Survival; Cyclic N-Oxides; Free Radical Scavengers; Hypoxia-Ischemia, Brain; Immunohistochemistry; Infarction, Middle Cerebral Artery; Malondialdehyde; Myelin Basic Protein; Nitrogen Oxides; Oligodendroglia; Rats; Staining and Labeling; Time Factors

Low density lipoprotein (LDL), the major carrier of plasma cholesterol, may enter the parenchyma of early multiple sclerosis (MS) lesions as a result of blood-brain barrier damage. We have used antibodies against LDL and epitopes found in LDL oxidized by two peroxidative end-products, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), to immunocytochemically stain MS plaques at different stages of pathology. Native LDL, epitopes of MDA-LDL, peptides of myelin basic protein and neutral lipid oil red O (ORO) staining were found to be co-localized within foamy macrophages in early and actively demyelinating MS plaques. Thus cholesterol esters, which are seen as Maltese crosses under polarized light in a proportion of foamy macrophages, appear to be derived from both LDL and myelin. ORO-negative astrocytes were strongly stained with the antibodies against 4-HNE-LDL and MDA-LDL, suggesting uptake of oxidatively modified protein products alone. Our findings suggest that a large proportion of the plasma LDL which enters the parenchyma of MS plaques is oxidatively modified in the lesion. Lipid peroxidation and oxidized LDL uptake by activated microglia and infiltrating macrophages in the early stages of MS plaque development may play important roles in demyelination.

Topics: Adult; Aged; Aldehydes; Astrocytes; Demyelinating Diseases; Humans; Immunohistochemistry; Lipoproteins, LDL; Macrophages; Malondialdehyde; Middle Aged; Multiple Sclerosis; Myelin Basic Protein; Oxidation-Reduction