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Biomedical subjects

I Singh

Publications and source records attributed to I Singh.

At least 109 records · Page 6Linked to original sources
PubMed1999

Manganese superoxide dismutase in rat liver peroxisomes: biochemical and immunochemical evidence.

By using highly purified peroxisomes from rat liver, we have shown that peroxisomes contain manganese superoxide dismutase (MnSOD) activity and a 23 kDa protein immunoreactive with antibodies against purified mitochondrial MnSOD. Immunocytochemical studies have also revealed immunoreaction (immunogold) with MnSOD antibodies in mitochondria and peroxisomes. Studies of the intraperoxisomal localization of MnSOD have shown that in peroxisomes MnSOD is a component of the peroxisomal limiting membranes and dense core. Furthermore, the MnSOD level in peroxisomes was modulated by oxidative stress conditions such as ischemia-reperfusion or the treatment with ciprofibrate, a peroxisomal proliferator. These findings suggest that MnSOD in peroxisomes may play an important role in the dismutation of superoxide generated on the peroxisomal membrane for keeping the delicate balance of the redox state.

Animals↗
PubMed1999

Increased peroxisomal fatty acid beta-oxidation and enhanced expression of peroxisome proliferator-activated receptor-alpha in diabetic rat liver.

To determine whether the increased fatty acid beta-oxidation in the peroxisomes of diabetic rat liver is mediated by a common peroxisome proliferation mechanism, we measured the activation of long-chain (LC) and very long chain (VLC) fatty acids catalyzed by palmitoyl CoA ligase (PAL) and lignoceryl CoA ligase and oxidation of LC (palmitic acid) and VLC (lignoceric acid) fatty acids by isotopic methods. Immunoblot analysis of acyl-CoA oxidase (ACO), and Northern blot analysis of peroxisome proliferator-activated receptor (PPAR-alpha), ACO, and PAL were also performed. The PAL activity increased in peroxisomes and mitochondria from the liver of diabetic rats by 2.6-fold and 2.1 -fold, respectively. The lignoceroyl-CoA ligase activity increased by 2.6-fold in diabetic peroxisomes. Palmitic acid oxidation increased in the diabetic peroxisomes and mitochondria by 2.5-fold and 2.7-fold, respectively, while lignoceric acid oxidation increased by 2.0-fold in the peroxisomes. Immunoreactive ACO protein increased by 2-fold in the diabetic group. The mRNA levels for PPAR-alpha, ACO and PAL increased 2.9-, 2.8- and 1.6-fold, respectively, in the diabetic group. These results suggest that the increased supply of fatty acids to liver in diabetic state stimulates the expression of PPAR-alpha and its target genes responsible for the metabolism of fatty acids.

ATP-Binding Cassette Transporters↗
PubMed1999

Role of P-selectin expression in hepatic ischemia and reperfusion injury.

BACKGROUND: Researchers have shown that reperfusion of ischemic tissues initiates a complex series of reactions that paradoxically injure tissues. Although several mechanisms have been proposed to explain the pathobiology of ischemic/reperfusion (I/R) injury, much attention has focused on adhesion molecules. Our research is intended to show the kinetics of P-selectin in the liver in response to I/R injury. METHODS: Left-lobar hepatic ischemia was induced for 30 min in 35 C57BL-6 mice and 20 P-selectin-deficient (K-O) mice. P-selectin expression was measured in these mice at 20 min, 2, 5, 12 and 24 h reperfusion times, as well as in control and sham animals. The animals were injected with radio-labeled P-selectin monoclonal antibody and the organs were harvested for counts/g tissue, expressed as the percentage injected dose. Serum liver enzymes were measured and pathological sections of ischemic and control livers were performed. The unpaired t-test was used for statistical analysis. RESULTS: P-selectin expression showed two peaks in this animal model. The first peak was at 20 min and the second peak at 5 h of reperfusion (p < 0.001). We documented an 8-fold increase in aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) levels 10 h following I/R injury. Pathological specimens showed periportal necrosis consistent with an ischemic event. P-selectin K-O mice showed no up-regulation as a separate control group, and the liver enzymes were significantly lower than the wild-type mice at 10 h (p < 0.001). CONCLUSION: P-selectin has a bimodal expression following hepatic I/R injury. The first peak is attributed to the Weibel-Palade bodies and the second to new translational P-selectin. We noted no difference in the up-regulation of P-selectin in the ischemic and non-ischemic liver lobes in the same animal.

Alanine Transaminase↗
PubMed1999

An evaluation of the no-scalpel vasectomy technique.

OBJECTIVE: To evaluate the magnitude and range of complications encountered during no-scalpel vasectomy (NSV) and to identify any limiting factor or contraindication to NSV. SUBJECTS AND METHODS: A total of 4255 men visiting a family welfare clinic of a city hospital in Delhi, India, or outpatients of the surgery department, opted for NSV; 4253 procedures were performed from September 1989 to December 1997, with two not performed because of technical difficulties. The success and complication rates were recorded. RESULTS: The complication rates with NSV were surprisingly low; seven complications were encountered, comprising two small haematomas (0.047%), three painful nodules (0.07%), three wound infections (0.07%) and two vasal fistulae, a complication not previously described. A meticulous procedure should avoid this last complication. The mean duration of NSV was 9.5 min. CONCLUSION: NSV is a refined and rapid technique of vasectomy with an extremely low complication rate. Being a minimally invasive procedure, it allays the fear of incision commonly encountered in men choosing vasectomy.

Contraindications↗
PubMed1999

Induction of the manganese superoxide dismutase gene by sphingomyelinase and ceramide.

The present study reports the effect of ceramide generated by hydrolysis of membrane sphingomyelin with bacterial sphingomyelinase (SMase) and of cell-permeable ceramide analogues on the expression of manganese superoxide dismutase (MnSOD). Incubation of the rat primary astrocytes with SMase led to a time- and dose-dependent increase in MnSOD activity. The increase in MnSOD activity was accompanied by an increase in MnSOD protein and mRNA. A similar effect on the expression of MnSOD was observed with the addition of cell-permeable ceramide analogues (C2 and C6). On the other hand, C2-dihydroceramide (N-acetylsphinganine), which lacks the functional critical double bond, was ineffective in inducing the expression of MnSOD. Nuclear run-on analysis showed that SMase and ceramide increased the rate of transcription of the MnSOD gene. Besides astrocytes, SMase was also found to induce the expression of MnSOD in rat mesangial cells, C6 glial cells, PC12 cells, and human skin fibroblasts. Markedly higher expression of mRNA, protein, and activity of MnSOD in skin fibroblasts from patients with Farber disease, a human disorder with pathognomonic accumulation of ceramide due to a deficiency of ceramidase, than in normal skin fibroblasts indicate that ceramide may act as a physiological inducer of MnSOD gene expression. However, stimulation of ceramide-mediated DNA fragmentation by antisense knockdown of MnSOD suggests that induction of MnSOD by ceramide is a protective response of the cell.

Animals↗
PubMed1999

Effect of nitric oxide on rhinovirus replication and virus-induced interleukin-8 elaboration.

Nitric oxide (NO) has been reported to have disparate effects in different viral infections. We conducted a study to determine whether rhinovirus (RV) infection is associated with production of NO, and to assess the effect of NO on RV-induced interleukin-8 (IL-8) elaboration both in vitro in monolayers of BEAS-2B cells, an immortalized respiratory epithelial cell line, and in MRC-5 cells, a diploid human embryonic lung fibroblast cell line, challenged with purified RV type 39, as well as in vivo, in experimental infections with RV type 23. Virus replication was not affected by pretreatment of cell monolayers with any of three different NO donors, and RV infection did not stimulate production of NO. Pretreatment of cell monolayers with either NO donors or inhibitors of NO synthase had no effect on RV-induced IL-8 elaboration measured either 6 or 24 h after virus challenge. Nasal wash specimens from RV-infected volunteers contained low concentrations of nitrite that were not different from the concentrations in specimens from sham-challenged subjects. The concentration of nitrite in these specimens did not change over the course of the subjects' rhinoviral illness. These results suggest that NO does not participate in the pathogenesis of RV infections.

Cell Line↗
PubMed1999

A transgenic animal model of osmotic cataract. Part 1: over-expression of bovine Na+/myo-inositol cotransporter in lens fibers.

PURPOSE: Intracellular osmotic stress is believed to be linked to the advancement of diabetic cataract. Although the accumulation of organic osmolytes (myo-inositol, sorbitol, taurine) is thought to protect the lens by maintaining osmotic homeostasis, the physiologic implication of osmotic imbalance (i.e., hyperosmotic stress caused by intracellular over-accumulation of organic osmolytes) on diabetic cataract formation is not clearly understood. Studies from this laboratory have identified several osmotic compensatory mechanisms thought to afford the lens epithelium, but not the lens fibers, protection from water stress during intervals of osmotic crisis. This model is founded on the supposition that the fibers of the lens are comparatively more susceptible to damage by osmotic insult than is the lens epithelium. To test this premise, several transgenic mouse lines were developed that over-express the bovine sodium/myo-inositol cotransporter (bSMIT) gene in lens fiber cells. METHODS: Of the several transgenic mouse lines generated, two, MLR14 and MLR21, were analyzed in detail. Transgenic mRNA expression was analyzed in adult and embryonic transgenic mice by a coupled reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization on embryonic tissue sections, respectively. Intralenticular myo-inositol content from individual mouse lenses was quantified by anion exchange chromatography and pulsed electrochemical detection. Ocular histology of embryonic day 15.5 (E15.5) embryos from both transgenic (TG) families was analyzed and compared to their respective nontransgenic (NTG) littermates. RESULTS: Both RT-PCR and in situ hybridization determined that transgene expression was higher in line MLR21 than in line MLR14. Consistent with this, intralenticular myo-inositol from MLR21 TG mice was markedly higher compared with NTG littermates or MLR14 TG mice. Histologic analysis of E15.5 MLR21 TG embryos disclosed a marked swelling in the differentiating fibers of the bow region and subcapsular fibers of the central zone, whereas the lens epithelium appeared morphologically normal. The lenticular changes, initiated early during lens development in TG MLR21 embryos, result in severe bilateral nuclear cataracts readily observable in neonates under normal rearing and dietary conditions. In contrast, TG MLR14 pups reared under standard conditions produced no lens opacity. CONCLUSIONS: Lens fiber swelling and related cataractous outgrowth positively correlated to the degree of lens bSMIT gene expression and intralenticular myo-inositol content. The affected (i.e., swollen) lens fibers appeared to be unable to cope with the water stress generated by the transgene-induced over-accumulation of myo-inositol and, as a result of this inability to osmoregulate, suffered osmotic damage due to water influx.

Animals↗
PubMed1999

The WHO simplified study protocol in practice: investigation of combined formulations supplied by the WHO.

SETTING: The benefits of fixed-dose combination (FDC) formulations of rifampicin, isoniazid and pyrazinamide over individual formulations are well recognised. OBJECTIVES: To evaluate the comparative bioavailability of antituberculosis drugs in FDC formulations and the same doses in separate formulations of antituberculosis drugs, using a simplified protocol developed by the World Health Organization (WHO). METHODS: Twenty healthy volunteers were included in the study and evaluated for bioequivalence of rifampicin in a cross-over experimental design. After administration of drugs the plasma concentration of rifampicin and desacetyl-rifampicin was measured repeatedly up to 8 hours in both plasma and urine. Various pharmacokinetic parameters of rifampicin, such as Cmax, Tmax, elimination rate constant, area under the curve (AUC) up to 8 hours and absorption efficiency were calculated. RESULTS: No significant differences were observed between the FDCs and separate formulations when Cmax, Tmax, AUC and absorption efficiencies were compared by parametric test and Hauschke's analysis. CONCLUSION: The WHO simplified protocol is suitable for evaluating bioequivalence of antituberculosis drugs.

Adolescent↗
PubMed1999

Bioequivalence study of rifampicin in fixed-dose combination of rifampicin and isoniazid vs. separate formulations.

The benefits of fixed-dose combinations of antituberculosis agents are well recognized by the World Health Organization (WHO) and International Union Against Tuberculosis and Lung Disease (IUATLD) and preferred over separate formulations. Therefore, a comparative bioequivalence study of rifampicin and isoniazid together in a fixed-dose combination and separately (at the same dose levels) was performed on a group of 12 healthy subjects. The study was designed as a single-blind, crossover experiment. Nine blood samples were collected from each subject over a period of 24 h. The plasma concentrations of rifampicin were assessed by a method developed in this laboratory. Various pharmacokinetic parameters of rifampicin such as AUC, Cmax, Tmax and t1/2 were also calculated. The study demonstrates that a fixed-dose combination (test formulation) and separate formulations (standard formulations) are bioequivalent for rifampicin.

Adult↗
PubMed1998

Presence of heterogeneous peroxisomal populations in the rat nervous tissue.

Peroxisomes were purified from the nervous tissue of 14-day-old rats by means of a Nycodenz gradient. Peroxisomal enzymes exhibited different sedimentation patterns: dihydroxyacetone phosphate acyl-transferase equilibrates at 1.142 g/ml together with the first peak of catalase; palmitoyl-CoA oxidase and D-amino acid oxidase activities are mainly recovered at 1.154 g/ml; the second peak of catalase is found at 1.175 g/ml. Morphological and semi-quantitative analyses of immunogold-labelled peroxisomes reveal profound heterogeneity of the particles. Very small (=0.2 microm diameter), electron dense vesicles containing catalase or thiolase, but devoid of other tested enzymes, are preferentially found in the light region, together with larger ( > 0.2 < 0.3 microm) and less electron dense palmitoyl-CoA oxidase-positive peroxisomes. At intermediate density (1.154 g/ml) peroxisomes of more uniform size (0.25-0.27 microm), containing palmitoyl-CoA oxidase or thiolase with or without catalase are preferentially found. This population extends toward the densest region of the gradient, where very large D-amino acid oxidase-containing peroxisomes are also found. In this region, smaller peroxisomes, often polymorphic, which are catalase- and thiolase-positive and D-amino acid oxidase/palmitoyl-CoA oxidase-negative, are also observed. The possibility that the heterogeneity of neural peroxisomes may reflect both cellular heterogeneity and ongoing peroxisomal biogenesis is discussed.

Acetyl-CoA C-Acetyltransferase↗
PubMed1998

Cytokine-mediated induction of ceramide production is redox-sensitive. Implications to proinflammatory cytokine-mediated apoptosis in demyelinating diseases.

The present study underlines the importance of reactive oxygen species in cytokine-mediated degradation of sphingomyelin (SM) to ceramide. Treatment of rat primary astrocytes with tumor necrosis factor-alpha (TNF-alpha) or interleukin-1beta led to marked alteration in cellular redox (decrease in intracellular GSH) and rapid degradation of SM to ceramide. Interestingly, pretreatment of astrocytes with N-acetylcysteine (NAC), an antioxidant and efficient thiol source for glutathione, prevented cytokine-induced decrease in GSH and degradation of sphingomyelin to ceramide, whereas treatment of astrocytes with diamide, a thiol-depleting agent, alone caused degradation of SM to ceramide. Moreover, potent activation of SM hydrolysis and ceramide generation were observed by direct addition of an oxidant like hydrogen peroxide or a prooxidant like aminotriazole. Similar to NAC, pyrrolidinedithiocarbamate, another antioxidant, was also found to be a potent inhibitor of cytokine-induced degradation of SM to ceramide indicating that cytokine-induced hydrolysis of sphingomyelin is redox-sensitive. Besides astrocytes, NAC also blocked cytokine-mediated ceramide production in rat primary oligodendrocytes, microglia, and C6 glial cells. Inhibition of TNF-alpha- and diamide-mediated depletion of GSH, elevation of ceramide level, and DNA fragmentation (apoptosis) in primary oligodendrocytes by NAC, and observed depletion of GSH, elevation of ceramide level, and apoptosis in banked human brains from patients with neuroinflammatory diseases (e.g. X-adrenoleukodystrophy and multiple sclerosis) suggest that the intracellular level of GSH may play a critical role in the regulation of cytokine-induced generation of ceramide leading to apoptosis of brain cells in these diseases.

Acetylcysteine↗
PubMed1998

Restoration of phytanic acid oxidation in Refsum disease fibroblasts from patients with mutations in the phytanoyl-CoA hydroxylase gene.

Refsum disease (RD) is biochemically characterized by the excessive accumulation of phytanic acid in tissues and body fluids due to deficiency of phytanoyl-CoA hydroxylase (PAHX). In this study, we screened three RD patients and identified a novel deletion (88 amino acids), and a missense mutation (Arg275Trp) in the previously reported PAHX cDNA (Jansen et al., 1997; Mihalik et al., 1997). Moreover, transfection of skin fibroblasts from two RD patients with wild-type PAHX gene restored the activity for alpha-oxidation of phytanic acid. Southern analysis on a somatic cell hybrid panel detected the PAHX gene on chromosome 10, corroborating radiation hybrid and homozygosity mapping data (Mihalik et al., 1997; Nadal et al., 1995).

Chromosome Mapping↗
PubMed1998

Inhibitors of protein phosphatase 1 and 2A differentially regulate the expression of inducible nitric-oxide synthase in rat astrocytes and macrophages.

Nitric oxide produced by inducible nitric-oxide synthase (iNOS) in different cells including brain cells in response to proinflammatory cytokines plays an important role in the pathophysiology of stroke and other neurodegenerative diseases. The present study underlines the importance of protein phosphatase (PP) 1 and 2A in the regulation of the differential expression of iNOS in rat primary astrocytes and macrophages. Compounds (calyculin A, microcystin, okadaic acid, and cantharidin) that inhibit PP 1 and 2A were found to stimulate the lipopolysaccharide (LPS)- and cytokine-mediated expression of iNOS and production of NO in rat primary astrocytes and C6 glial cells. However, these inhibitors inhibited the LPS- and cytokine-mediated expression of iNOS and production of NO in rat resident macrophages and RAW 264.7 cells. Similarly, okadaic acid, an inhibitor of PP 1/2A, stimulated the iNOS promoter-derived chloramphenicol acetyltransferase activity in astrocytes and inhibited the iNOS promoter-derived chloramphenicol acetyltransferase activity in macrophages, indicating that okadaic acid also differentially regulates the transcription of the iNOS gene in astrocytes and macrophages. The observed stimulation of the expression of iNOS in astrocytes and the inhibition of the expression of iNOS in macrophages with the inhibition of PP 1/2A activity clearly delineate a novel role of PP 1/2A in the differential regulation of iNOS in rat astrocytes and macrophages. Because the activation of NF-kappaB is necessary for the induction of iNOS and the expression of tumor necrosis factor (TNF)-alpha also depends on the activation of NF-kappaB, we examined the effect of okadaic acid on the LPS-mediated activation of NF-kappaB and production of TNF-alpha in rat primary astrocytes and macrophages. Interestingly, in both cell types, okadaic acid stimulated the LPS-mediated DNA binding as well as transcriptional activity of NF-kappaB and production of TNF-alpha. This study suggests that the stimulation of iNOS expression in astrocytes by inhibitors of PP 1/2A is possibly due to the stimulation of NF-kappaB activation; however, activation of NF-kappaB is not sufficient for the induction of iNOS in macrophages and that apart from NF-kappaB some other signaling pathway(s) sensitive to PP 1 and/or PP 2A is/are possibly involved in the regulation of iNOS in macrophages. This differential induction of iNOS as compared with similar activation of NF-kappaB by inhibitors of PP 1/2A indicates the involvement of different intracellular signaling events for the induction of iNOS in two cell types of the same animal species.

Animals↗
PubMed1998

Lovastatin and sodium phenylacetate normalize the levels of very long chain fatty acids in skin fibroblasts of X- adrenoleukodystrophy.

The present study underlines the importance of lovastatin, an inhibitor of 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) reductase, and the sodium salt of phenylacetic acid (NaPA), an inhibitor of mevalonate pyrophosphate decarboxylase, in normalizing the pathognomonic accumulation of saturated very long chain fatty acids (VLCFA) in cultured skin fibroblasts of X-adrenoleukodystrophy (X-ALD) in which the ALD gene is either mutated or deleted. Lovastatin or NaPA alone or in combination stimulated the beta-oxidation of lignoceric acid (C24:0) and normalized the elevated levels of VLCFA in skin fibroblasts of X-ALD. Ability of lovastatin and NaPA to normalize the pathognomonic accumulation of VLCFA in skin fibroblasts of X-ALD may identify these drugs as possible therapeutics for X-ALD.

Adrenoleukodystrophy↗
PubMed1998

Abnormality in catalase import into peroxisomes leads to severe neurological disorder.

Peroxisomal disorders are lethal inherited diseases caused by either defects in peroxisome assembly or dysfunction of single or multiple enzymatic function(s). The peroxisomal matrix proteins are targeted to peroxisomes via the interaction of peroxisomal targeting signal sequences 1 and 2 (PTS1 or PTS2) with their respective cytosolic receptors. We have studied human skin fibroblast cell lines that have multiple peroxisomal dysfunctions with normal packaging of PTS1 and PTS2 signal-containing proteins but lack catalase in peroxisomes. To understand the defect in targeting of catalase to peroxisomes and the loss of multiple enzyme activities, we transfected the mutant cells with normal catalase modified to contain either PTS1 or PTS2 signal sequence. We demonstrate the integrity of these pathways by targeting catalase into peroxisomes via PTS1 or PTS2 pathways. Furthermore, restoration of peroxisomal functions by targeting catalase-SKL protein (a catalase fused to the PTS1 sequence) to peroxisomes indicates that loss of multiple functions may be due to their inactivation by H2O2 or other oxygen species in these catalase-negative peroxisomes. In addition to enzyme activities, targeting of catalase-SKL chimera to peroxisomes also corrected the in situ levels of fatty acids and plasmalogens in these mutant cell lines. In normal fibroblasts treated with aminotriazole to inhibit catalase, we found that peroxisomal functions were inhibited to the level found in mutant cells, an observation that supports the conclusion that multiple peroxisomal enzyme defects in these patients are caused by H2O2 toxicity in catalase-negative peroxisomes. Moreover, targeting of catalase to peroxisomes via PTS1 and PTS2 pathways in these mutant cell lines suggests that there is another pathway for catalase import into peroxisomes and that an abnormality in this pathway manifests as a peroxisomal disease.

Animals↗
PubMed1998

Sphingomyelinase and ceramide stimulate the expression of inducible nitric-oxide synthase in rat primary astrocytes.

The sphingomyelin signal transduction pathway is known to play a role in mediating the action of various cytokines. Here we examined the possible role of the sphingomyelin signaling pathway on lipopolysaccharide (LPS)- and cytokine-mediated production of NO and the expression of inducible nitric-oxide synthase (iNOS). Sphingomyelinase (SMase) treatment of astrocytes increased the cellular levels of ceramide without the induction of NO production. However, incubation of LPS or cytokine-stimulated astrocytes with SMase or by increasing intracellular ceramide by cell-permeable ceramide analogs (C2- or C6-ceramide) or inhibitor of ceramidase (N-oleoyl ethanolamine) led to a time- and dose-dependent increase in the production of NO. This increase in NO production was accompanied by an increase in iNOS activity, iNOS protein, and iNOS mRNA. Similar to astrocytes, SMase or ceramide analogs also stimulated the LPS- and cytokine-mediated expression of iNOS in the C6 glial cell line. Since activation of NF-kappaB is necessary for the induction of iNOS, we examined the effect of SMase and C2-ceramide on the activation of NF-kappaB. Although SMase or C2-ceramide alone was ineffective in activating NF-kappaB, both stimulated the LPS-mediated activation of NF-kappaB in LPS-activated astrocytes. Inhibition of ceramide and LPS-mediated induction of iNOS by antioxidant inhibitors of NF-kappaB (N-acetylcysteine and pyrrolidine dithiocarbamate) suggest that the stimulatory effect of ceramide on the induction of iNOS is due to the stimulation of NF-kappaB activation and that cellular redox plays a role in the activation of NF-kappaB and induction of iNOS. Inhibition of LPS-mediated as well as LPS and ceramide-mediated induction of iNOS and activation of NF-kappaB by PD98059, a specific inhibitor of activation of mitogen-activated protein (MAP) kinase kinase (MEK), and FPT inhibitor II, a selective inhibitor of Ras farnesyl protein transferase, indicate that the Ras-MAP kinase pathway is involved in LPS-ceramide induced activation of NF-kappaB and induction of iNOS, and that ceramide-mediated signaling events probably converge into the LPS-modulated MAP kinase signaling pathway resulting in greater activation of NF-kappaB and iNOS induction. This study illustrates a novel role of the sphingomyelin-ceramide signaling pathway in stimulating the expression of iNOS via LPS- or cytokine-mediated activation of NF-kappaB in astrocytes.

Acetylcysteine↗