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S M LeVine

Publications and source records attributed to S M LeVine.

At least 19 recordsLinked to original sources
PubMed2003

Heme oxygenase-1 in SJL mice with experimental allergic encephalomyelitis.

The expression of heme oxygenase-1 (HO-1) is increased in the CNS of mice and rats with experimental allergic encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). To investigate the role of HO-1 in EAE, a putative inhibitor [tin-protoporphyrin IX (Sn-PP IX)] of HO-1 was administered to SJL mice during active disease. Sn-PP IX (200 micromol/kg) attenuated clinical scores, weight loss, and some signs of pathology in comparison to vehicle treatment. Glutathione levels were greater in treated EAE mice than in those receiving vehicle, indicating lower oxidative stress in the former group. These data suggest that inhibition of HO-1 attenuated disease and suppressed free radical production. In the SJL model of EAE, extravasated blood is present in the CNS, and iron released by HO-1 from this heme source may not be adequately sequestered by ferritin, allowing for iron-mediated tissue damage. Thus, HO-1 may act to amplify the disease process in this model.

Animals↗
PubMed2003

Analysis of protein induction in the CNS of SJL mice with experimental allergic encephalomyelitis by proteomic screening and immunohistochemistry.

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease characterized by demyelination and inflammatory infiltrates in the CNS, and it is an animal model of multiple sclerosis. Piperonyl butoxide (PBO) suppresses disease in EAE mice, and it exhibits a dual effect on cytochrome P450s that manifests in a transient inhibitory phase followed by induction. In order to identify the expression of proteins associated with EAE, a proteomic screening was performed on hindbrain microsomes from control + vehicle, control + PBO, EAE + vehicle, and EAE + PBO female mice. Glucose regulated protein 94 (Grp94) and coagulation factor VIII were among the proteins identified in EAE + vehicle and EAE + PBO mice. Immunohistochemical staining of Grp94 was present in some neurons and oligodendrocytes in hindbrain sections from control animals, and in some cells within inflammatory infiltrates in EAE animals. Since Grp94 (also known as Gp96) can partake in antigen presentation and induction of proinflammatory cytokine expression, its presence in these cells suggests that it may play a role in the pathogenesis of EAE. Coagulation factor VIII is carried and protected by von Willebrand factor. Immunohistochemical staining of von Willebrand factor revealed its presence in some vessels within hindbrain sections from control animals. In EAE animals, the number of labeled vessels was significantly increased, and extracellular granular deposits were observed around labeled vessels indicating that the breakdown of the blood-brain barrier that occurs in EAE permitted its extravasation into the CNS. Additional proteins were identified in the different groups of mice by proteomic screening, but confirmation of their expression profile awaits investigations by independent measures.

Animals↗
PubMed2003

Sphingolipid profile in the CNS of the twitcher (globoid cell leukodystrophy) mouse: a lipidomics approach.

Globoid cell leukodystrophy (Krabbe disease) is caused by mutations in galactosylceramidase, a lysosomal enzyme that acts to digest galactosylceramide, a glycolipid concentrated in myelin, and psychosine (galactosylsphingosine). Globoid cell leukodystrophy has been identified in many species including humans and twitcher mice. Several studies on human tissue have examined the lipid profile in this disease by gas, liquid or thin layer chromatography. Electrospray ionization tandem mass spectrometry combined with reverse phase HPLC has become a powerful alternative strategy, used here to compare the sphingolipid profile of pons/medulla tissue from twitcher mice with control tissue. In this lipidomics LC-MS approach, we scanned for precursors of m/z 264 to obtain a semi-quantitative profile of ceramides and galactosylceramides. Sphingosine-1-phosphate, C18:0 ceramide, C22:0 ceramide and C24:0 ceramide levels were reduced in the pons/medulla of twitcher mice compared to levels in control mice at 31 and 35-37 days of age. The levels of C22:0 and C24:0 galactosylceramide were similar between twitcher and control specimens and there was a trend toward reduced levels of C24:1 galactosylceramide and C24:1 hydroxy-galactosylceramide in twitcher specimens. Psychosine, C 16:0 ceramide and C 18:0 galactosylceramide levels were increased in the CNS of twitcher mice compared to levels in control mice. These data indicate that there is a trend toward decreased levels of long chain fatty acids and increased levels of shorter chain fatty acids in galactosylceramides and ceramides from twitcher mice compared with control mice, and such changes may be due to demyelination characteristic of acute pathology.

Animals↗
PubMed2001

Cuprizone and piperonyl butoxide, proposed inhibitors of T-cell function, attenuate experimental allergic encephalomyelitis in SJL mice.

Multiple sclerosis (MS) and its animal model, experimental allergic encephalomyelitis (EAE), are autoimmune demyelinating diseases with autoreactive T-cells acting as important mediators of pathogenesis. Cuprizone, a copper chelator, and piperonyl butoxide (PBO), a pesticide synergist, are implicated to inhibit T-cell activation and function. The purpose of this study was to assess whether either of these agents would suppress PLP-peptide-induced EAE in the SJL mouse. Indeed, treatment with cuprizone beginning 1 week prior to disease induction, and PBO administration from days 1 to 9 of EAE, significantly attenuated EAE clinical severity. Furthermore, both agents decreased blood CD4+/CD8+ ratios, and reduced signs of chronic graft vs. host disease (GVHD) indicating attenuation of an immune T-cell response. These results suggest that cuprizone and PBO suppress EAE and use of these agents will provide insights into the mechanisms of T-cell mediated diseases.

Animals↗
PubMed2001

IL-6 deficiency allows for enhanced therapeutic value after bone marrow transplantation across a minor histocompatibility barrier in the twitcher (globoid cell leukodystrophy) mouse.

Bone marrow transplantation (BMT) has therapeutic value for twitcher (globoid cell leukodystrophy) mice, which suffer from a genetic deficiency of the lysosomal enzyme galactosylceramidase that leads to progressive demyelination and early death. Preliminary investigations indicated that a semiallogeneic BMT resulted in graft vs. host disease (GVHD) in twitcher mice but not normal mice. Increased production of the cytokine IL-6 has been demonstrated in twitcher mice, and it has been linked with induction of GVHD. We investigated the effects of BMT in twitcher/IL-6 deficient mice and compared these findings with those from transplanted twitcher and control mice. After a semiallogeneic BMT, 11.4% of controls died within few weeks while the rest survived >100 days without GVHD. In contrast, 85% of the transplanted twitcher mice died by 70 days and 65% developed clinical signs of GVHD, e.g., alopecia and weight loss. In transplanted twitcher/IL-6 deficient mice, only 21% died by Day 70, none had alopecia, and 23% had weight loss. There was no difference in the onset day and severity of twitching between twitcher and twitcher/IL-6 deficient mice after BMT. In transplanted twitcher/IL-6 deficient mice, there was improvement of BBB integrity and a decrease in globoid cell number compared with nontransplanted twitcher/IL-6 deficient mice. In summary, these results demonstrate that an underlying pathology like globoid cell leukodystrophy leads to activation of GVHD responses in a donor-host combination that would not normally induce GVHD. Furthermore, IL-6 seems to play a key role because a deficiency of IL-6 results in a better prognosis.

Animals↗
PubMed2000

TNF-receptor 1 deficiency fails to alter the clinical and pathological course in mice with globoid cell leukodystrophy (twitcher mice) but affords protection following LPS challenge.

Twitcher mice have an autosomal recessive mutation in the gene for the lysosomal enzyme galactosylceramidase, which is the same gene that is affected in human globoid cell leukodystrophy (Krabbe's disease). The failure to digest galactosylceramide and psychosine leads to initial pathological changes in oligodendrocytes. Secondary pathological changes that include infiltrating macrophages and other inflammatory responses have been postulated to promote the disease course. TNFalpha levels are elevated in twitcher mice compared to control animals, and studies on another demyelinating disease, experimental allergic encephalomyelitis, indicate that TNF promotes pathogenesis via TNF-receptor 1 (TNF-R1). In the present study, twitcher/TNF-R1 deficient mice were generated, and the clinical and pathological course was compared between these mice and regular twitcher mice. There was no statistical evidence for any differences between these two groups of mice for all clinical (life span, weight loss, onset day of twitching) and pathological (demyelination, astrocyte gliosis, macrophage infiltration) measures that were examined. If mice were administered an intraperitoneal injection of LPS, then twitcher/TNF-R1 deficient mice had a longer [corrected] life span and a decreased [corrected] disruption to the blood-brain barrier compared to regular twitcher mice. These results showed that TNF-R1 is not sufficiently activated to affect the pathological and/or clinical signs during the natural course of this disease. However, when there is a secondary insult, TNF-R1 activation does lead to a significant acceleration of the development of clinical and pathological signs.

Animals↗
PubMed2000

L-cycloserine slows the clinical and pathological course in mice with globoid cell leukodystrophy (twitcher mice).

Globoid cell leukodystrophy (Krabbe's disease) is an autosomal recessive disease that affects the lysosomal enzyme galactosylceramidase. Galactosylceramidase removes galactose from galactosylceramide and psychosine, which are derived from sphingosine. In the present study, L-cycloserine (an inhibitor of 3-ketodyhydrosphingosine synthase) was administered to the twitcher mouse, an authentic model of globoid cell leukodystrophy. Twitcher mice treated with L-cycloserine had a significantly longer life span and a delayed onset of weight loss than vehicle-injected twitcher mice. Pathological features such as macrophage infiltration and astrocyte gliosis also were less in treated twitcher mice. These results indicate that substrate reduction therapy may have therapeutic value for individuals with residual enzymatic activity, e.g., individuals with late onset disease or individuals with partial enzyme replacement via bone marrow transplantation. In these cases, a reduction in galactosylceramide and psychosine synthesis would enable residual enzymatic activity to keep up with the accumulation of these substrates that would otherwise lead to pathology.

Animals↗
PubMed2000

Heme oxygenase-1 and NADPH cytochrome P450 reductase expression in experimental allergic encephalomyelitis: an expanded view of the stress response.

Oxidative stress is implicated in the pathogenesis of experimental allergic encephalomyelitis (EAE), a model for multiple sclerosis. Heme oxygenase-1 (HO-1) is a heat shock protein induced by oxidative stress. HO-1 metabolizes the pro-oxidant heme to the antioxidant biliverdin and CO. HO-1 requires electrons, donated by NADPH cytochrome P450 reductase (henceforth, reductase), for catalytic activity. EAE was induced with a peptide of proteolipid protein in SJL mice, and the expression of HO-1 and reductase in the hindbrain was analyzed. HO-1 protein levels were significantly increased in EAE animals compared with control mice. HO-1 expression was present in ameboid macrophages, reactive microglia, and astrocytes in white matter tracks. Bergmann glia and ameboid macrophages also were occasionally stained in the molecular layer of the cerebellum. Unlike HO-1, reductase protein levels decreased with disease severity. HO-1 and reductase were associated with each other in endoplasmic reticulum micelles, suggesting that the decrease in reductase does not interfere with its association with HO-1. In cells that express HO-1, the association of reductase with HO-1 should competitively inhibit the interaction of reductase with cytochrome P450 isozymes and thereby limit free radical production as the latter two enzymes act cooperatively to produce superoxide. The increase in HO-1 together with the decrease in reductase may be part of a common defense mechanism attempting to minimize tissue damage in several neurological conditions.

Animals↗
PubMed2000

Chemical changes in the photoreceptor outer segments due to iron induced oxidative stress: analysis by Fourier transform infrared (FT-IR) microspectroscopy.

Oxidative stress is thought to be an important pathogenic mechanism in many diseases of the retina. The purpose of this study was to investigate the chemical changes that are present in the photoreceptor outer segments of the retina following exposure to oxidative stress. Fourier transform infrared (FT-IR) microspectroscopy enables the characterization and semi-quantitation of chemical functional groups in microscopic regions of tissue sections. This technique was used to evaluate the chemical changes in the outer segments following exposure to ferrous sulfate, which promotes oxidative tissue damage. A reduction of C=C-H and C=O functional groups was observed in the outer segments of iron-injected eyes compared to vehicle-injected eyes at 3 days following injection, which is prior to major histological changes that occur by 7 days. These functional groups are found in docosahexaenoic acid (DHA), which is present at a high concentration in the outer segments. DHA contains a series of six cis-conjugated double bonds, which are vulnerable to free radical attack, and the reduction of these unsaturation group absorptions suggests that DHA was degraded and/or removed from the outer segments. An unexpected finding was that several other chemical functional groups increased in concentration over time in the outer segments of vehicle-injected eyes compared to non-injected eyes. These increases generally did not include C=C-H or C=O, which suggests that either DHA was being degraded while other organic molecules were being concentrated, or that production of DHA failed to be upregulated in vehicle-injected eyes. In summary, there was a loss of both C=C-H and C=O functional group concentrations in the outer segments of iron-injected eyes, and there was an increased concentration of several other chemical functional groups following trauma induced by vehicle injection.

Animals↗
PubMed2000

A multiple course trial of desferrioxamine in chronic progressive multiple sclerosis.

Chronic progressive multiple sclerosis (MS) is a debilitating disease that is often refractory to treatment. We have previously published a pilot study using a single 2-week course of the iron chelating drug, desferrioxamine (DFO), as a candidate drug for treatment of this form of MS. In this study, we gave 9 patients up to 8 courses of this regimen over 2 years. The patients tolerated the medication well. During the study, 1 patient improved, 3 remained stable, and 5 worsened by 0.5 on the Kurtzke expanded disability status scale (EDSS). These results suggest that, while the drug is well tolerated, no effect on disease progression can be identified at this dosage level. A more continuous dosage schedule could be studied as a candidate for treatment in this disease process.

Adult↗
PubMed1999

Microchemical analysis of retina layers in pigmented and albino rats by Fourier transform infrared microspectroscopy.

Fourier transform infrared (FT-IR) microspectroscopy is a powerful technique that can be used to collect infrared spectra from microscopic regions of tissue sections. The infrared spectra are evaluated to chemically characterize the absorbing molecules. This technique can be applied to normal or diseased tissues. In the latter case, FT-IR microspectroscopy can reveal chemical changes that are associated with discrete regions of lesion sites, which can provide insights into the chemical mechanisms of disease processes. In the present study, FT-IR microspectroscopy was used to analyze sections of retina from normal (pigmented) and albino rats. The outer segments of retinas from pigmented animals were found to have unusually strong absorption values for C&z.dbnd6;C-H unsaturation and carbonyl functional groups. Docosahexaenoic acid (DHA), a major constituent of lipids in the outer segments, also had particularly high absorption values for these functional groups, which suggests that it is responsible for those enhanced absorption values. Absorbance values for the unsaturation and carbonyl functional groups were substantially reduced in the outer segments of retinas from albino animals. This finding, together with data from other studies on light-induced oxidative events in the retina, indicates a loss of DHA by a light-induced mechanism in albino animals. The outer nuclear layer had strong absorbance values for H-C-OH and P&z. dbnd6;O functional groups, which is likely due to the sugar phosphate backbone of DNA. The outer and inner plexiform layers were found to contain greater concentrations of CH(2) and C&z.dbnd6;O functional groups than the outer and inner nuclear layers, which is due to the high concentration of synaptic connections in the former layers. In summary, FT-IR microspectroscopy revealed a unique chemical profile in the outer segments compared to other retinal layers, and this profile was altered in albino animals.

Animals↗
PubMed1999

Ferritin, transferrin and iron concentrations in the cerebrospinal fluid of multiple sclerosis patients.

The concentrations of ferritin, transferrin and iron were measured in the cerebrospinal fluid (CSF) of multiple sclerosis (MS) and control patients. Ferritin levels were significantly elevated in the CSF of chronic progressive active MS patients (4.71+/-0.54 ng/ml) compared to levels in normal individuals (3.07+/-0.17 ng/ml). MS patients with active or stable relapsing-remitting disease had ferritin levels that were comparable to those found in normal individuals. There were no significant differences in transferrin or iron levels in the CSF between MS and normal individuals. Both ferritin and transferrin levels were elevated in patients that had high CSF IgG values but not in patients with a high IgG index. Since ferritin binds iron, the increase of CSF ferritin levels in chronic progressive MS patients could be a defense mechanism to protect against iron induced oxidative injury. Ferritin levels could be a laboratory measure that helps to distinguish between chronic progressive and relapsing-remitting MS.

Chronic Disease↗
PubMed1999

IL-6 deficiency causes enhanced pathology in Twitcher (globoid cell leukodystrophy) mice.

The expression of IL-6 is greatly enhanced in the twitcher mouse (S. M. LeVine and D. C. Brown, 1997, J. Neuroimmunol. 73, 47-56), which is an authentic animal model of globoid cell leukodystrophy (Krabbe's disease). In order to investigate the role of IL-6 in this disease, twitcher/IL-6-deficient mice were generated and the pathology was compared between them and regular twitcher mice. Twitcher/IL-6-deficient mice had a more severe disease than regular twitcher mice: they had an earlier onset day of twitching, a greater number of PAS-positive cells, a greater susceptibility to LPS, an exaggerated gliotic response around some vessels, an elevated level of TNF-alpha, and a compromised blood-brain barrier, which was evaluated by three independent measures. This latter finding indicates that IL-6 plays a role in maintaining the integrity of the BBB, and it raises the possibility that IL-6 functions in a similar manner in other diseases of the CNS. LPS was found to greatly shorten the life of twitcher and twitcher/IL-6-deficient mice compared to genotyped-matched saline-injected mice. This result indicates that a proinflammatory condition can exacerbate an underlying CNS pathology, which could help explain why some leukodystrophy patients display their initial symptoms following a fever or blow to the head.

Animals↗
PubMed1998

Iron quantification in cerebrospinal fluid.

Several studies have attempted to measure iron levels in cerebrospinal fluid (CSF), which is believed to contain very low levels of iron. In general, the assays used in these studies suffered from poor reproducibility or lack of sensitivity. In the present study, an assay was developed that enables iron quantitation in CSF using 150 microliters of undiluted CSF, sample digestion, dot blotting, Perls' histochemistry, 3,3'-diaminobenzidine enhancement, and densitometry. Inter- and intraassay variability was low and sensitivity high (279 pg iron in 100 microliters). There were negligible readings for standard curves utilizing copper in place of iron. The iron content in eight normal CSF samples was 61.01 +/- 18.3 (SD) micrograms/liter, and in nine normal sera it was 1332.7 +/- 408.2 (SD) micrograms/liter. The present assay enables reliable measures of iron levels in biological samples. This assay should enable future studies that address how CSF iron levels change during the course of various disease states.

Histocytochemistry↗
PubMed1998

Chemical analysis of multiple sclerosis lesions by FT-IR microspectroscopy.

Fourier transform infrared microspectroscopy can be used to collect infrared spectra from microscopic regions of tissue sections. If spectra are collected along a grid pattern, then maps of chemical functional groups can be produced and correlated to tissue histopathology. In the present study, white matter from multiple sclerosis and control brains were examined. Mapping experiments were designed such that 17 spectra were collected at 200 microm intervals along a line that was partially or wholly within a multiple sclerosis lesion site or within a representative white matter region of control tissue. Data analysis was based on earlier in vitro studies which found that the carbonyl at 1740 cm(-1) increases when lipids become oxidized (Free Rad. Biol. Med. 16:591-601, 1994), and the amide I peak at approximately 1660 cm(-1) broadens when proteins become oxidized (FEBS Let. 362:165-170, 1995). The results indicated that the C=O to CH2 ratio (1740 cm(-1):1468 cm(-1)) was elevated at several collection points in lesion sites from multiple sclerosis brains compared to values from white matter of control brains. Inspection of the amide I peak at 1657 cm(-1) revealed that it was broadened towards 1652 cm(-1) in multiple sclerosis tissues but not control tissues. These results suggest that lipids and proteins could be oxidized at active multiple sclerosis lesion sites. The localization of these products to lesion sites supports a role for free radicals in the pathogenesis of multiple sclerosis.

Aged↗
PubMed1998

Desferrioxamine suppresses experimental allergic encephalomyelitis induced by MBP in SJL mice.

Data from several studies indicate that free radicals have a pathogenic role in experimental allergic encephalomyelitis (EAE). Iron can contribute to free radical damage by catalyzing the formation of hydroxyl radical, inducing secondary initiation of lipid peroxidation and by promoting the oxidation of proteins. The iron chelator, desferrioxamine, can limit these oxidative reactions and it can scavenge peroxynitrite independent of iron chelation. Two previous studies have examined the therapeutic value of desferrioxamine in EAE. One study observed an effect when disease was induced by spinal cord homogenates (J. Exp. Med. 160, p. 1532, 1984), but a second study found no therapeutic value of desferrioxamine for myelin basic protein (MBP)-induced EAE (J. Neuroimmunol. 17, p. 127, 1988). In the second study, the drug was only administered during the preclinical stages of disease. Since desferrioxamine scavenges free radicals and prevents their formation, we hypothesized that the drug should be given during the active stage of disease to have therapeutic value. We first demonstrated that the drug enters the CNS around inflammatory cells in EAE animals. In animals treated during the active stage of MBP-induced EAE, the clinical signs were significantly reduced compared to vehicle-treated animals. The iron-bound form of this drug, ferrioxamine, was without therapeutic value. A derivative of desferrioxamine, hydroxylethyl starch (HES)-desferrioxamine, has a greater plasma half-life than desferrioxamine and it was also tested. Although there was a suggestion of improvement in these animals, the effects were less than that observed for desferrioxamine which may be related to the greater molecular size of HES-desferrioxamine. In summary, these data suggest that chelation of iron is an effective therapeutic target for EAE.

Animals↗
PubMed1998

Iron deposits in the central nervous system of SJL mice with experimental allergic encephalomyelitis.

Iron has been proposed to promote oxidative tissue damage in multiple sclerosis (MS). In order to gain insights about how iron gets processed during MS, the deposition of iron was investigated in the CNS of mice with experimental allergic encephalomyelitis (EAE), which is a commonly used animal model of MS. Control mice (adjuvant only) and EAE mice (myelin basic protein plus adjuvant), were sacrificed at 4-8 days (preclinical phase), 10-13 days (clinical phase), or 18 days (recovery phase) post injection. Sections from the cerebrum, hindbrain, and cervical, thoracic and lumbar spinal cord were stained as previously described (J. Neurosci. Res. 29:413, 1991), and scored blindly for histopathological staining. There was minimal histopathological staining at any age in control animals or during the preclinical stage in EAE animals. At the clinical stage of EAE, stained pathological features (macrophages, extravasated RBC and granular staining) were significantly increased compared to the preclinical stage. In the recovery phase, macrophage and granular staining persisted but there was loss of extravasated RBC. Dual labeling studies revealed that granular deposits were present in astrocytes and in locations that appeared to be extracellular. In order to gain insights about the origin of iron deposits in EAE mice, additional studies were performed on brains of mice with extravasated blood lesions. These brains had granular, macrophage and RBC staining. Thus, each of the stained features in EAE animals could be due to the extravasation of blood which occurs in the SJL model of EAE, although some of the iron could have originated from myelin and oligodendrocytes damaged during EAE.

Animals↗