Cell Damage In Mice Research Articles

Taurine mechanism in preventing retinal cell damage from acute ocular hypertension through GTPBP3 regulation.

We aimed to explore the protective effects and underlying mechanisms of taurine on retinal cells during acute ocular hypertension (AOH)-induced damage. Retinal morphology, apoptosis, mitochondrial structure, electroretinography, expression of GTP binding protein 3 (GTPBP3), and molecules in the unfolded protein response (UPR) were examined in an AOH mouse model and wild-type (WT) mice with or without intravitreal injection of taurine. For in vitro experiments, the GTPBP3 expression and endoplasmic reticulum (ER) stress were examined in R28 cell line under hydrogen peroxide (H2O2)-induced damage or hypoxia/reoxygenation (H/R)-induced damage, with or without taurine pretreatment. Taurine pretreatment alleviated retinal damage caused by AOH modeling. The GTPBP3 expression level decreased after AOH injury, and taurine pretreatment reversed this reduction. Retinas with decreased GTPBP3 expression showed reduced retinal ganglion cell (RGC) function, which could be reversed by intravitreal taurine injection. In H2O2-, H/R-, and AOH-induced damage, UPR were activated and alleviated by taurine pretreatment. GTPBP3 knockdown in R28 cells also activated the UPR, which was alleviated by taurine. A UPR activator downregulated GTPBP3 levels in normal R28 cells, whereas a UPR inhibitor upregulated GTPBP3 levels in GTPBP3 knockdown R28 cells. In conclusion, this study provides important evidence that taurine prevents retinal cell damage in mice exposed to AOH and modulates GTPBP3 expression via the UPR pathway. Interventions targeting this mechanism can be used as potential therapeutic targets for AOH damage.

DDIT4/mTOR signaling pathway mediates cantharidin-induced hepatotoxicity and cellular damage.

Cantharidin (CTD) extracted from the traditional Chinese medicine Mylabris has significant therapeutic effects on various tumors. However, the high toxicity of CTD can cause serious liver damage, although the related molecular mechanisms remain unclear. In this study, we established models of CTD-induced liver and L-O2 cell damage in mice in vivo and in vitro. Subsequently, liver function indicators were detected in mouse serum, while liver tissues were subjected to pathological and transmission electron microscopy observations. L-O2 cell activity was investigated using the CCK-8 assay, and the mRNA and protein expression of DNA damage-induced transcription factor 4 (DDIT4) in liver tissue and L-O2 cells was detected using qPCR, immunohistochemistry, and western blotting. Western blotting was also used to detect the expression levels of autophagy- and apoptosis-related proteins in liver tissue and L-O2 cells. After RNAi interference with DDIT4, Rap, and 3-MA treatment, autophagy and apoptosis of L-O2 cells were detected using western blotting, flow cytometry, transmission electron microscopy, and confocal microscopy. Following CTD exposure, the mouse liver showed significant pathological damage and an increase in autophagic lysosomes, while the vitality of L-O2 cells showed a significant decrease. CTD led to a significant increase in the mRNA and protein levels of DDIT4 in both liver tissue and L-O2 cells, as well as a significant increase in LC3-II, Beclin1, and Bax, whereas p-mTOR and Bcl-2 were significantly decreased. Following DDIT4 interference and 3-MA treatment, the levels of autophagy and apoptosis induced by CTD in L-O2 cells were reduced. After Rap treatment, both autophagy and apoptosis of CTD-induced L-O2 cells were significantly enhanced. The molecular mechanism of CTD-induced toxicity in mouse liver and L-O2 cells is mainly through DDIT4/mTOR signaling pathway activation, leading to an increase in autophagy and apoptosis levels.

CRISPR-CasRx-mediated disruption of Aqp1/Adrb2/Rock1/Rock2 genes reduces intraocular pressure and retinal ganglion cell damage in mice

Glaucoma affects approximately 80 million individuals worldwide, a condition for which current treatment options are inadequate. The primary risk factor for glaucoma is elevated intraocular pressure. Intraocular pressure is determined by the balance between the secretion and outflow of aqueous humor. Here we show that using the RNA interference tool CasRx based on shH10 adenovirus-associated virus can reduce the expression of the aqueous humor circulation related genes Rock1 and Rock2, as well as aquaporin 1 and β2 adrenergic receptor in female mice. This significantly reduced intraocular pressure in female mice and provided protection to the retina ganglion cells, ultimately delaying disease progression. In addition, we elucidated the mechanisms by which the knockdown of Rock1 and Rock2, or aquaporin 1 and β2 adrenergic receptor in female mice, reduces the intraocular pressure and secures the retina ganglion cells by single-cell sequencing.

Toll-like receptor 4-mediated endoplasmic reticulum stress induces intestinal paneth cell damage in mice following CLP-induced sepsis

A marked elevation of TLR4 was observed in various organs of septic mice. The mechanism of TLR4 in intestinal epithelial cell damage in sepsis remains unclear. CLP mice models were used to assess the role of TLR4 in intestinal Paneth cell damage by histological, polymerase chain reaction, western-blot analyses. The ileal expression of TLR4 was increased by more than five-fold after CLP. CLP significantly increased 7-day mortality and was associated with a higher murine sepsis score (MSS), closely related with increased TLR4 expression. Histological staining revealed that a reduced number of Paneth cells, accompanied by reduced lysozyme and defensin alpha 5(DEF-5) expression as detected by PCR. Of note, the expression levels of ATF6, XBP1 and CHOP increased in the ileal of the sepsis group. Meanwhile, the uncleaved p90 ATF6 was markedly reduced and cleaved p50 ATF6 was increased in the sepsis group. Intriguingly, The TAK-242 had improved intestinal mucosal injury, reduced the expression of ATF6, XBP1 and CHOP and relieved the cleavage of ATF6. We found that increased the expression level of TLR4 in the ileal of CLP mice promoted the depletion of Paneth cell and reduced LYZ and DEF-5 expression. Furthermore, our findings suggested that TLR4-mediated the hyperactivation of ER stress, via activating the ATF6/CHOP pathway, might be one of the mechanisms associated with Paneth cells loss and dysfunction during intestinal barrier impairment of sepsis.

POTENCY OF SOURSOP LEAF (ANNONA MURICATA L.) DECOCTION WATER AS A TRIGGER FOR MICE (MUS MUSCULLUS) LIVER CELL REGENERATION MARKED BY CYCLIN D1 EXPRESSION DUE TO RHODAMINE B INFECTION

Soursop leaf (Annona muricata L.) is one of the plants that contains chemical compounds such as acetogenins, flavonoids, saponins, tannins, triterpenoids and glycosides where this group of chemical compounds has the potential as antioxidants to ward off free radicals. This study aimed to determine the effect of soursop leaf decoction in regenerating liver cells of male mice of the Balb/C strain induced by rhodamine B through the expression of cyclin D1. The 25 mice were divided into 5 groups, namely group I was given standard feed, group II was given standard feed and rhodamine B 0.4 mg/ml, groups III, IV and V were given standard feed, rhodamine B 0.4 mg/ml, and water. soursop leaf decoction with doses of 3.64 mg/g BW, 7.28 mg/g BW, and 10.92 mg/g BW for each group. The treatment was carried out for 14 days by giving soursop leaf boiled water after rhodamine B induction for 7 days. The results showed that the boiled water of soursop leaves at a dose of 10.92 mg/g BW had a significant effect on reducing levels of SGOT and SGPT (p<0.05) and could regenerate mice liver cells through the expression of cyclin D1. Based on the results of the study, it can be concluded that the antioxidant content of soursop leaf boiled water can prevent liver cell damage in mice and increase cell regeneration power

Hexa Histidine-Tagged Recombinant Human Cytoglobin Deactivates Hepatic Stellate Cells and Inhibits Liver Fibrosis by Scavenging Reactive Oxygen Species.

Background and AimsAntifibrotic therapy remains an unmet medical need in human chronic liver disease. We report the antifibrotic properties of cytoglobin (CYGB), a respiratory protein expressed in hepatic stellate cells (HSCs), the main cell type involved in liver fibrosis.Approach and Results Cygb‐deficient mice that had bile duct ligation–induced liver cholestasis or choline‐deficient amino acid–defined diet–induced steatohepatitis significantly exacerbated liver damage, fibrosis, and reactive oxygen species (ROS) formation. All of these manifestations were attenuated in Cygb‐overexpressing mice. We produced hexa histidine–tagged recombinant human CYGB (His‐CYGB), traced its biodistribution, and assessed its function in HSCs or in mice with advanced liver cirrhosis using thioacetamide (TAA) or 3,5‐diethoxycarbonyl‐1,4‐dihydrocollidine (DDC). In cultured HSCs, extracellular His‐CYGB was endocytosed and accumulated in endosomes through a clathrin‐mediated pathway. His‐CYGB significantly impeded ROS formation spontaneously or in the presence of ROS inducers in HSCs, thus leading to the attenuation of collagen type 1 alpha 1 production and α‐smooth muscle actin expression. Replacement the iron center of the heme group with cobalt nullified the effect of His‐CYGB. In addition, His‐CYGB induced interferon‐β secretion by HSCs that partly contributed to its antifibrotic function. Momelotinib incompletely reversed the effect of His‐CYGB. Intravenously injected His‐CYGB markedly suppressed liver inflammation, fibrosis, and oxidative cell damage in mice administered TAA or DDC mice without adverse effects. RNA‐sequencing analysis revealed the down‐regulation of inflammation‐ and fibrosis‐related genes and the up‐regulation of antioxidant genes in both cell culture and liver tissues. The injected His‐CYGB predominantly localized to HSCs but not to macrophages, suggesting specific targeting effects. His‐CYGB exhibited no toxicity in chimeric mice with humanized livers.ConclusionsHis‐CYGB could have antifibrotic clinical applications for human chronic liver diseases.

A standardized crush tool to produce consistent retinal ganglion cell damage in mice.

A standardized crush tool to produce consistent retinal ganglion cell damage in mice.

PENGARUH PEMBERIAN PROPOLIS LEBAH TERHADAP GAMBARAN HISTOPATOLOGI HEPAR MENCIT (Mus musculus) BETINA YANG DIPAPAR LOGAM BERAT PB ASETAT [Pb(C2H3O2)2

Lead acetate in the hepatobiliary system may cause peroxidation catalysis of unsaturated fatty acids, reduce nitrogenoxide and increase hydroxyl radical. Lead acetate produces oxidative stress characterized by free radical formation and inhibits lipid peroxidation. Giving antioxidants can neutralize free radicals from the detrimental effects that arise on the process or excess oxidation reactions. The purpose of this research was to find out how the effect of bee propolis on histopathologic images of hepatic mice (Mus musculus) of females exposed to lead acetate [Pb(C2H3O2)2]. The subjects were 25 mice (Mus musculus) mushulus of BALB/C strain with average weight 25-30 gram and 8 weeks old, divided into 5 treatment groups, each consisting of 5 heads per group. The K- group was given a Tween 80 solution at a doses of 0.5 mg/kgBW for 20 consecutive days. The K+ group, which was given only lead acetate at a doses of 10 mg/kgBW orally for 10 days. P1, P2, and P3 were given 10 mg/kgBW lead acetate solution orally for 10 days. The following 10 days were given bee propolis with doses of P1 200 mg/kgBW, P2 400 mg/kgBW, and P3 800 mg/kgBW. On the 21th days the mice were dissected, to observe the extent of the damage. All data were performed using a statistical test with Kruskal Wallis test and if there was a marked difference between treatment groups (p<0.05), then the Mann-Whitney test was followed. The results obtained that bee propolis can repair hepatic cell damage in mice (Mus musculus) of females exposed to lead acetate. Increased dose of bee propolis is ineffective in repairing hepatic cell damage in mice (Mus musculus) of females exposed to lead acetate.

Exosomal miRNA Let-7 from Menstrual Blood-Derived Endometrial Stem Cells Alleviates Pulmonary Fibrosis through Regulating Mitochondrial DNA Damage.

Idiopathic pulmonary fibrosis (IPF) is a prototype of chronic, progressive, and fibrotic lung disease with high morbidity and high mortality. Menstrual blood-derived stem cells (MenSCs) have proven to be an attractive tool for the treatment of acute lung injury and fibrosis-related diseases through immunosuppression and antifibrosis. However, whether MenSC-derived exosomes have the similar function on pulmonary fibrosis remains unclear. In the present study, exosomes secreted from MenSCs (MenSCs-Exo) were verified by transmission electron microscope (TEM), nanoparticle tracking analyzer (NTA), and western blotting. And MenSC-Exo addition significantly improved BLM-induced lung fibrosis and alveolar epithelial cell damage in mice, mainly reflected in BLM-mediated enhancement of the fibrosis score, blue collagen deposition, dry/wet gravity ratio, hydroxyproline and malondialdehyde levels, and downregulation of glutathione peroxidase, which were all robustly reversed by MenSC-Exo management. Additionally, BLM- and TGF-β1-evoked cellular reactive oxygen species (ROS), mitochondrial DNA (mtDNA) damage, and cell apoptosis were rescued by MenSCs-Exo in vivo and in vitro. Further study indicated that the MenSCs-Exo could transport miRNA Let-7 into recipient alveolar epithelial cells. Let-7 inhibitor administration significantly blocked the exosome-mediated improvement role on lung fibrosis in mice. Mechanistically, Let-7 was able to regulate the expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX1) through binding to its 3′-UTR region. Forced expression of LOX1 promoted the expression of apoptosis-related protein and mtDNA damage markers via regulating NLRP3 which was also confirmed in BLM model mice under the combination therapy of the exosome and Let-7 inhibitor. Collectively, this study demonstrates that exosomal Let-7 from MenSCs remits pulmonary fibrosis through regulating ROS, mtDNA damage, and NLRP3 inflammasome activation. This provides a new approach of exocytosis on the treatment of fibrotic lung disease.

Effect of trehalose on manganese-induced mitochondrial dysfunction and neuronal cell damage in mice.

Chronic overexposure to manganese (Mn) has been verified to induce mitochondrial dysfunction, which is related to oxidative damage. The autophagic-lysosomal degradation pathway plays a vital role in the removal of impaired mitochondria through a specific quality control mechanism termed mitophagy. However, trehalose functions as an inducer of autophagy by an mTOR-independent mechanism, and little data report its effect on Mn-induced mitochondrial dysfunction. To explore the possibility that trehalose could be effective in interfering with the Mn-induced mitochondrial dysfunction, we used trehalose (2% and 4% (g/vol (mL))) in a mouse model of manganism. Our data showed that mice developed weary motor and behavioural deficits after exposure to Mn for 6weeks. Overexposure to Mn resulted in mitochondrial dysfunction and neuronal cell damage in the basal nuclei of mice, which could be ameliorated by trehalose pre-treatment. Moreover, our results indicated that trehalose pre-treatment significantly reduced the oxidative damage and enhanced the activation of mitophagy. The findings clearly demonstrated that trehalose could relieve Mn-induced mitochondrial and neuronal cell damage through its antioxidative and mitophagy-inducing effects.

The signal transduction of xanthone as a protector on 2-methoxyethanol-induced cardiac cell damage in mice.

This research aims at investigating the role of antioxidant of xanthone on 2-methoxyethanol (2-ME)-induced cardiac cell damage in mice. Forty mice were grouped into: (1) The control group (mice were given with distilled water), (2) the ME group (mice were given with 2-ME 200 mg/kg BW orally), and (3) the treatment group (mice were given of xanthone with doses 60 mg, 120 mg, 240 mg/kg BW orally and were also given 2-ME 200 mg/kg BW). Their blood samples were taken to measure the level of lactate dehydrogenase (LDH) and creatinine kinase-MB (CK-MB). Heart tissues were also taken to determine the malondialdehyde (MDA), histological findings of heart damage, and the immunohistochemical of the expression of superoxide dismutase (SOD) and glutathione peroxidase (GPx). The administration of 2-ME resulted in a significant increase level of the LDH, CK-MB, MDA, and a decrease in SOD and GPx expression were compared with the control group. The 2-ME also induced loss of the normal structure of heart cells and necrosis. However, treatment with the xanthone, only dose 240 mg/kg BW significantly decrease the level of LDH, CK-MB, MDA, and increase SOD, GPx expression. The xanthone 240 mg/kg BW also demonstrated significantly improved heart cell damage. From the results, it is concluded that the xanthone are a potent antioxidant in against 2-ME-induced cardiac toxicity in mice, through increasing SOD and GPx expression, and also inhibiting LDH, CK-MB and MDA.

Genetic inhibition of cyclophilin D protects against bile acid or ethanol and fatty acid induced pancreatic ductal epithelial cell damage in mice

Genetic inhibition of cyclophilin D protects against bile acid or ethanol and fatty acid induced pancreatic ductal epithelial cell damage in mice

Obesity-Mediated Autophagy Insufficiency Exacerbates Proteinuria-induced Tubulointerstitial Lesions

Obesity is an independent risk factor for renal dysfunction in patients with CKDs, including diabetic nephropathy, but the mechanism underlying this connection remains unclear. Autophagy is an intracellular degradation system that maintains intracellular homeostasis by removing damaged proteins and organelles, and autophagy insufficiency is associated with the pathogenesis of obesity-related diseases. We therefore examined the role of autophagy in obesity-mediated exacerbation of proteinuria-induced proximal tubular epithelial cell damage in mice and in human renal biopsy specimens. In nonobese mice, overt proteinuria, induced by intraperitoneal free fatty acid-albumin overload, led to mild tubular damage and apoptosis, and activated autophagy in proximal tubules reabsorbing urinary albumin. In contrast, diet-induced obesity suppressed proteinuria-induced autophagy and exacerbated proteinuria-induced tubular cell damage. Proximal tubule-specific autophagy-deficient mice, resulting from an Atg5 gene deletion, subjected to intraperitoneal free fatty acid-albumin overload developed severe proteinuria-induced tubular damage, suggesting that proteinuria-induced autophagy is renoprotective. Mammalian target of rapamycin (mTOR), a potent suppressor of autophagy, was activated in proximal tubules of obese mice, and treatment with an mTOR inhibitor ameliorated obesity-mediated autophagy insufficiency. Furthermore, both mTOR hyperactivation and autophagy suppression were observed in tubular cells of specimens obtained from obese patients with proteinuria. Thus, in addition to enhancing the understanding of obesity-related cell vulnerability in the kidneys, these results suggest that restoring the renoprotective action of autophagy in proximal tubules may improve renal outcomes in obese patients.

Nigrostriatal damage after systemic rotenone and/or lipopolysaccharide and the effect of cannabis

In this study, we compared the effects of systemic rotenone, lipopolysaccharide (LPS), or both rotenone and LPS on oxidative stress and nigrostriatal cell damage in mice. We further investigated the therapeutic potential of cannabis in these rodent models of Parkinson's disease. Rotenone (1.5 mg/kg, subcutaneously, three times per week), LPS (0.2 mg/kg, intraperitoneally, daily), or LPS plus rotenone was given alone or in combination with cannabis (20 mg/kg, expressed as Δ9-tetrahydrocannabinol, subcutaneously daily) for 2 weeks. Mice were tested for behavioral changes on the 14th day after different treatments. Biochemical markers of oxidative stress such as malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (nitrite), paraoxonase 1 (PON1) activity as well as monoamine neurotransmitters in the brain were determined. Histopathology, tyrosine hydroxylase immunoreactivity (TH-ir), inducible nitric oxide synthase (iNOS), and caspase-3 immunohistochemistry were also performed. Either rotenone or LPS injection was followed by increased MDA and decreased GSH in the cortex, striatum, and the rest of the brain (subcortex). There was increased nitrite and decreased PON1 activity in the cortex and subcortex. The increase in nitrite by combined LPS–rotenone in the cortex was significantly higher than that caused only LPS. In the subcortex, nitrite was significantly increased compared with either agent alone. The biochemical changes induced by rotenone, LPS, or rotenone + LPS were reduced, but not prevented by cannabis. In the striatum, the administration of only cannabis induced mild degenerative changes with shrunken neurons and pyknotic nuclei, a slight decrease in TH-ir, and mild iNOS and caspase-3 immunoreactivities. LPS injection was followed by pyknotic and apoptotic nuclei and perinuclear cytoplasmic vacuoles and decreased TH-ir with mild iNOS and caspase-3 immunoreactivities. Meanwhile, marked striatal neurodegeneration was observed after rotenone with shrunken and distorted neurons, pericellular haloes, inflammation, and hemorrhage. Markedly decreased TH-ir and increased iNOS and caspase-3 immunoreactivities were observed. The loss of pigmented neurons, the decrease of TH-ir, and the increase in both iNOS and caspase-3 immunoreactivities were markedly increased by administering both rotenone and LPS. The administration of cannabis did not reduce nigrostriatal damage due to rotenone, LPS, or rotenone + LPS, although an improvement in striatal TH-ir was observed. Thus, (1) systemic rotenone or LPS increased oxidative and nitrosative stress in brain and (2) induced nigrostriatal neuronal damage; (3) the effect was not limited to the striatum but involved other areas such as the cerebral cortex and hippocampus; (4) the neuronal damage caused by rotenone was increased in the presence of systemic inflammation; (5) rotenone induced caspase-3-mediated apoptosis; (6) cannabis reduced brain oxidative stress but failed to alleviate nigrostriatal damage due to rotenone, LPS, or rotenone + LPS; and (7) cannabis increased TH immnunostaining in the striatum after rotenone, LPS, or rotenone + LPS. This effect of cannabis does not appear to reflect a neuroprotective effect and might be due to increased striatal dopamine levels by cannabis.

Diphlorethohydroxycarmalol, isolated from the brown algae Ishige okamurae, protects against radiation-induced cell damage in mice

The aim of this study was to evaluate the radioprotective effects of diphlorethohydroxycarmalol (DPHC), isolated from the brown algae Ishige okamurae, in mice subjected to gamma irradiation. DPHC significantly decreased the level of radiation-induced intracellular reactive oxygen species in cultured Chinese hamster lung fibroblast (V79-4) cells ( p < 0.05), enhanced cell viability that decreased after exposure to γ-rays, and reduced radiation-induced apoptosis in the V79-4 cells. Pretreatment with DPHC (100 mg/kg) in mice prior to irradiation significantly protected the intestinal crypt cells in the jejunum ( p < 0.01) and maintained villi height ( p < 0.01), compared with those of the vehicle-treated irradiated group. Mice pretreated with DPHC also exhibited dose-dependent increases in the bone marrow cell viability. The dose-reduction factor for gamma irradiation in the DPHC-pretreated mice was 2.05 at 3.5 days after irradiation. These results suggest that DHPC plays a role in protecting cells from irradiation-induced apoptosis, through the scavenging of reactive oxygen species in vitro, and that DPHC significantly protected intestinal progenitor cells and bone marrows cells that were decreased by gamma irradiation in vivo.

A Na+/Ca2+ exchanger isoform, NCX1, is involved in retinal cell death after N‐methyl‐D‐aspartate injection and ischemia–reperfusion

We investigated the expression of Na(+)/Ca(2+) exchanger (NCX) and the functional role of NCX in retinal damage by using NCX1-heterozygous deficient mice (NCX1(+/-)) and SEA0400 (2-[4-[(2,5-difluorophenyl)methoxy] phenoxy]-5-ethoxyaniline), a selective NCX inhibitor in vivo. We also examined the role of NCX in oxygen-glucose deprivation (OGD) stress with a retinal ganglion cell line (RGC-5) cell culture in vitro. The expression of NCX1 was confirmed and entirely localized in retina by immunoblotting and immunohistochemistry, respectively. NCX1(+/-) mice possessed significant protection against retinal damage induced by intravitreal injection of N-methyl-D-aspartate (NMDA). SEA0400 at 3 and 10 mg/kg significantly reduced NMDA- or high intraocular pressure-induced retinal cell damage in mice. Furthermore, SEA0400 reduced the number of TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling)-positive cells and the expression of phosphorylated mitogen-activated protein kinases (ERK1/2, JNK, p38) induced by NMDA injection. In RGC-5, SEA0400 at 0.3 and 1 microM significantly inhibited OGD-induced cell damage. OGD-induced cell damage was aggravated by ouabain (a Na(+),K(+)-ATPase inhibitor) at 100 microM, and this increased damage was significantly reduced by SEA0400 at 1 microM. In conclusion, these results suggest that NCX1 may play a role in retinal cell death induced by NMDA and ischemia-reperfusion.

Supplementation of taurine and β-cyclodextrin to mice administered ethanol restores lipid metabolism and damaged liver

In this study we investigated the effects of taurine and β-cyclodextrin (β-CD) supplementation on lipid metabolism and hepatic cell damage in mice administered with ethanol. The supplemented mice consisted of a control (CO) group, an ethanol (AL) group, and an ethanol + taurine + β-CD (ATB) group. The ethanol (45 g/L) and/or taurine (76.5 mg/L) + β-CD (153 mg/L) treatments were administered for 6 months via the drinking water. At the termination of the treatment period the following measurements were made: serum and hepatic lipids, serum enzymes, and the extent of hepatic lipid peroxidation. The serum total cholesterol and triacylglycerol levels were higher in the AL group than in the CO and ATB groups. In the ATB group, there were significant decreases in total cholesterol and triacylglycerol levels, as well as a slight decrease in the low-density lipoprotein cholesterol level. Hepatic triacylglycerol and malondialdehyde levels were higher in the AL group than in the CO and ATB groups. Furthermore, the ATB group had significant decreases in hepatic triacylglycerol and malondialdehyde levels. The serum levels of glutamic-oxaloacetic transaminase, glutamic-pyruvic transaminase, alkaline phosphatase, and lactate dehydrogenase were higher in the AL group than in the CO group. The ATB group had significant decreases in glutamic-pyruvic transaminase and the liver damage index, as well as slight decreases of glutamic-oxaloacetic transaminase, alkaline phosphatase, and lactate dehydrogenase. These data suggest that the combined supplementation of taurine and β-CD improves and restores lipid metabolism and liver cell damage in mice with ethanol-induced injuries.

Serum thymic factor prevents LPS-induced pancreatic cell damage in mice via up-regulation of Bcl-2 expression in pancreas.

The protective effect of synthetic serum thymic factor (FTS) nonapeptide on lipopolysaccharide (LPS)-induced pancreatic cell damage in 10-week-old BALB/c male mice was investigated. Mice were divided into three groups. Group I was treated with LPS (10 micro g/head; i.p.) (LPS-treated mice). Group II was administered with FTS (50 micro g/head; i.p.) 24 hr before treatment with LPS and complemented immediately before LPS injection with FTS (50 micro g/head; i.p.) (FTS-administered mice). Group III was only treated with the same volume of saline (control mice). Treatment of LPS in vivo resulted in the destruction of pancreatic acinar cells. In those cells, many apoptotic cells were detected by immunohistochemistry using an anti-single stranded DNA antibody. Immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) revealed that LPS treatment also caused low or a lack of insulin expression in pancreatic islets. In contrast, morphological change was not seen and apoptotic cell death was suppressed in pancreatic cells of FTS-administered mice. Moreover, insulin expression was normal in those mice. FTS administration enhanced expression of Bcl-2 mRNA levels in pancreatic tissues and IL-6 mRNA levels in splenocytes significantly compared with those of LPS treatment at 3 hr after LPS injection. These findings suggest that FTS prevents LPS-induced cell damage via enhancing Bcl-2 expression in the pancreas and systemic IL-6 production.

Immunohistochemical Detection of Cyp2E1 and 2-S-Glutathionyl Acetate in Murine Lung Tumors: Diminished Formation of Reactive Intermediates of 1,1-Dichloroethylene

This study investigates the potential of urethane-induced lung tumors to activate 1,1-dichloro-ethylene (DCE), a chemical that causes Clara cell damage in mice. Metabolism of DCE is catalyzed by the cytochrome P450 isozyme CYP2E1 to the DCE-epoxide, as assessed by formation of 2-S-gluta-thionyl acetate (GTA), the glutathione (GSH)-conjugated product of the epoxide. Immunohistochemical studies were performed in normal non-tumor- and tumor-bearing mice to determine lung cells that contained CYP2E1 available for DCE metabolism. The site of GTA formation was also determined. The results showed that most of the CYP2E1 were expressed in Clara cells from normal lung and in uninvolved tissue of tumor-bearing lung. In contrast, CYP2E1 was minimally expressed in neoplastic tissue, including hyperplasias, adenomas, and carcinomas. Parallel studies of adjacent lung sections revealed that GTA immunostaining was most intense in Clara cells of normal lung tissue and in uninvolved tissue of tumor-bearing lungs from DCE-treated mice. However, GTA staining was negligible at all tumor sites. These results demonstrated that the cellular sites where CYP2E1 was expressed were the same as those in which the GTA metabolite was identified. They further showed that expression of both CYP2E1 and GTA was markedly reduced in hyperplasias, adenomas, and carcinomas. These observations suggest that these tissue types are defective in their capability for bioactivation of DCE.

The role of acrolein in allyl alcohol-induced lipid peroxidation and liver cell damage in mice

Male NMRI mice were fed a sucrose diet for 48 hr in order to reduce the hepatic glutathione content and to level off its diurnal variation. After administration of allyl alcohol (AA: 1.1 mmol/kg), hepatic glutathione (24.3 ± 7.0 nmol GSH/mg protein) was almost totally lost within the first 15min (<0.5 nmol GSH/mg protein). Subsequently, a massive lipid perioxidation was observed, i.e. the animals exhaled 414 ± 186 nmol ethane/kg/hr compared to 0.9 ± 0.8 of controls, and the hepatic TBA- reactive compounds had increased from 55 ± 16 pmol/mg protein in controls to 317 ± 163 after 1 hr. Concomitantly, a 40–45% loss of the polyunsaturated fatty acids (arachidonic and docosahexaenoic acid) in the liver lipids was observed. About 80% of the cytosolic alcohol dehydrogenase activity and about 50% of the microsomal P450-content were destroyed. In vivo-inhibition of alcohol dehydrogenase by pyrazole or induction of aldehyde dehydrogenase by phenobarbital abolished AA-induced liver damage as well as glutathione depletion and lipid peroxi- dation, while inhibition of aldehyde dehydrogenase by cyanamide made a subtoxic dose of AA (0.60 mmol/kg) highly toxic. These results strongly favour the importance of acrylic acid formation as an additional detoxification pathway. Enhanced hepatic levels of glutathione protected in vivo against the damaging effects of AA. Depletion of the liver glutathione content by phorone or diethylmaleate alone caused marginally enhanced lipid peroxidation (phorone) but no liver cell damage. Mono- oxygenase inhibitors (metyrapone, diethyldithiocarbamate, α-naphthoflavone) or an inducer (benz( a)pyrene) did not affect AA-induced toxicity. The ferric iron chelator desferoxamine- methanesulfonate prevented AA-induced lipid peroxidation and liver cell damage in vivo. In vitro, acrolein alone failed to initiate lipid peroxidation in soy bean phospholipid liposomes or in mouse liver microsomes. Thus, acrolein not only impairs the glutathione defense system but also directly destroys cellular proteins and evokes lipid peroxidation by an indirect iron-depending mechanism.