Comparison of ephedrine and pseudoephedrine contents in 34 Kampo extracts containing Ephedrae Herba used clinically in Japan.

Ephedrae Herba is among the important crude drugs prescribed in Kampo medicine for the treatment of cold, flue, rhinitis, nasal congestion, cough, and asthma. The active ingredients of Ephedrae Herba, ephedrine (E) and pseudoephedrine (PE), are potent sympathomimetic compounds that stimulate α-, ß1-, and ß2-adrenoceptors resulting in dilatation and alleviation of nasal mucosal hyperemia. Hypertension, palpitations, insomnia, and dysuria are the main adverse effects of E and PE, which can be avoided by determining the actual contents of these alkaloids in Kampo extracts containing Ephedrae Herba. However, the extraction efficiencies of E and PE from Ephedrae Herba contained in Kampo formulas in combination with other crude drugs remain unknown. Therefore, we comprehensively determined the E and PE contents of 34 Kampo extracts containing Ephedrae Herba used clinically in Japan. The E and PE contents per daily dosage in Kampo extracts were generally proportional to the compounding amount of Ephedrae Herba. In contrast, the extraction efficiencies of E or PE were not constant and not influenced by the pH of the extracts. We assume that the extraction efficiencies of E and PE may be independently affected by other constituent crude drugs. Thus, it is necessary to investigate the cause and mechanism in the future. In conclusion, these results show that the E and PE content of each Kampo formulation can be estimated from the compounding amount of Ephedrae Herba. Therefore, the amount of Ephedrae Herba should be carefully considered to ensure the safe use of Kampo formulations containing Ephedrae Herba.

Hochuekkito exerts the anti-allergic effects via activating regulatory T cells in a murine model of contact hypersensitivity.

Hochuekkito (HET) is a Kampo prescription, used for the clinical treatment of skin diseases such as atopic dermatitis (AD), in Japan. Oral administration of HET exerts anti-allergic effects in an experimental dermatitis mice model and in patients with atopic dermatitis; however, the mechanism underlying the anti-allergic effects of HET is still unclear. Therefore, we investigated the immunopharmacological properties of the anti-allergic actions of HET using a 2,4,6-trinitrochlorobenzene (TNCB)-induced murine contact hypersensitivity (CHS) model and adoptive cell transfer experiments. Oral administration of HET (1.4 g/kg) exhibited anti-allergic effects in a TNCB-induced CHS model via activation of Tregs; this activation was observed even without antigen sensitization in donor mice. Activation was dependent on the duration of HET administration and required at least 4 days of dosing. In addition, the anti-allergic effects of HET through the activation of Tregs were not antigen specific. Flow cytometry results indicated that the proportion of CD4+CD25+Foxp3+ cells in the splenic lymphocytes increased after oral administration of HET. Therefore, oral administration of HET induced both inducible regulatory T cells (iTregs) and thymus-derived naturally occurring regulatory T cells (nTregs). Ginseng radix and Bupleuri radix were involved in the anti-allergic actions of HET through the induction and/or activation of Tregs; Bupleuri radix participated in the activation of nTregs. In conclusion, our findings suggest that HET exerts the anti-allergic effects through the induction and/or activation of Tregs. These findings elucidate the usefulness of HET as an immunomodulator.

Orengedokuto exerts anti-allergic effects via inhibition of effector T cell activation in a murine model of contact hypersensitivity.

Orengedokuto (OGT) is a Kampo prescription that has been used for the treatment of inflammation, hypertension, gastrointestinal disorders, and liver and cerebrovascular diseases. It is also used for the treatment of skin diseases such as urticaria and atopic dermatitis. We previously studied its anti-allergic effects of OGT on the murine model of 2,4,6-trinitrochlorobenzene (TNCB)-induced contact hypersensitivity (CHS) and demonstrated that it significantly suppresses ear swelling in a dose-dependent manner. However, the mechanism underlying this activity remained unknown. Here, we sought to identify the mechanism involved. Using a murine model of TNCB-induced CHS, together with adoptive cell transfer experiments, we found that the anti-allergic effects of OGT may be due to the inhibition of effector T cell activation and not the induction and/or activation of regulatory T cells. Flow cytometry analysis revealed that oral administration of OGT suppressed the increase in CD8+CD44highCD62L+ cell number in draining lymph nodes (dLNs) of mice sensitized with 5% TNCB. Additionally, ex vivo experiments confirmed the suppressive effect of OGT on the activation of effector T cells, as interferon-γ (IFN-γ) production by cultured lymphocytes obtained from 5% TNCB-sensitized mice and stimulated with anti-CD3ε and anti-CD28 monoclonal antibodies was reduced by OGT administration. In conclusion, our finding suggests that OGT exerts anti-allergic effects by regulating the activation of effector T cells involved in inflammatory skin diseases such as atopic dermatitis.

Juzentaihoto Exerts Anti-Allergic Effects by Inhibiting Effector T-Cell Activation and Inducing and/or Activating Regulatory T Cells in a Murine Model of Contact Hypersensitivity.

BACKGROUND: Juzentaihoto (JTT) is a Kampo prescription that has been used clinically for treating skin diseases such as atopic dermatitis in Japan. We have previously studied the anti-allergic effects of JTT on 2,4,6-trinitrochlorobenzene (TNCB)-induced contact hypersensitivity (CHS) in mice and demonstrated that it significantly suppresses ear swelling in a dose-dependent manner. However, the mechanism underlying the anti-allergic actions of JTT is obscure. METHODS: We investigated the mechanism underlying the anti-allergic effects of JTT using a TNCB-induced murine CHS model and adoptive cell transfer experiments. RESULTS: We showed that the anti-allergic effects of JTT are due to inhibition of effector T-cell activation and induction and/or activation of regulatory T cells. Furthermore, ex vivo experiments confirmed the effect of JTT on the activation of effector T cells and regulatory T cells, as interferon-γ production decreased, whereas interleukin (IL)-10 production increased, in the cultured lymphocytes obtained from 5% TNCB-sensitized mice treated with anti-CD3ε and anti-CD28 monoclonal antibodies. Flow cytometry showed that the CD4+CD25+Foxp3+, CD4+CD25+Foxp3-, and CD8+CD122+ cell population increased after oral administration of JTT. Finally, the anti-allergic effect of JTT by inducing and/or activating regulatory T cells (Tregs) was confirmed to be mediated by IL-10 through in vivo neutralization experiments with anti-IL-10 monoclonal antibodies. CONCLUSION: We suggested that JTT exerts anti-allergic effects by regulating the activation of effector T cells and Tregs involved in murine CHS model.

Effect of glucoglycyrrhizin on IgE-mediated immediate hypersensitivity in mice.

To evaluate the pharmacological property of glucoglycyrrhizin (GGL), a unique glycoside of glycyrrhetinic acid (GA), we investigated the anti-allergic effect of GGL on IgE-mediated immediate hypersensitivity in mice. GGL exhibited the antiallergic effect against IgE-mediated immediate hypersensitivity. At a dose of 100 mg/kg, GGL exhibited antiallergic activity equivalent to that of glycyrrhizin (GL). Furthermore, the pretreatment with anti-GA monoclonal antibody eliminated the antiallergic action of GGL. These results indicated that GGL may act in the same way as GL in the human body. Its safety should be verified for its use as a drug similar to GL.

Effect of hot water extract of a glycyrrhizin-deficient strain of Glycyrrhiza uralensis on contact hypersensitivity in mice.

To evaluate the medicinal properties of a glycyrrhizin (GL)-deficient strain of Glycyrrhiza uralensis, we investigated the anti-allergic effect of the hot water extract obtained from its roots on contact hypersensitivity in mice, and compared it with that of the hot water extract of a commercial crude drug, Glycyrrhiza Radix. The hot water root extract of the GL-deficient strain contained glucoglycyrrhizin (GGL) and rhaoglucoglycyrrhizin (RGL) instead of GL, and it showed anti-allergic activity against contact hypersensitivity in a fashion similar to that of the crude drug extract. We further confirmed the presence of glycyrrhetinic acid (GA), a major metabolite of GL, in mice serum after oral administration of the hot water root extract of a GL-deficient strain. We demonstrated that GGL underwent hydrolysis by intestinal microflora of mice to form GA. These results suggest that a GL-deficient strain of G. uralensis is a useful medicinal resource since the glycosides of GA work in a fashion similar to that of GL when orally administered.

Evaluation of the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems III: anti-allergic effects of hot water extracts on IgE-mediated immediate hypersensitivity in mice.

To evaluate the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems, we investigated anti-allergic action in mice using IgE-mediated immediate hypersensitivity. Hot water extracts obtained from the roots of Glycyrrhiza uralensis cultivated using two systems were orally administered at a dose of 100 mg/kg as glycyrrhizin (GL) and compared with the commercial crude drug, Glycyrrhizae Radix. Both the artificial hydroponic and artificial hydroponic-field hybrid cultivated root extracts showed anti-allergic effects on IgE-mediated immediate hypersensitivity in mice, as did the commercial crude drugs. These results highlight the potential for artificially cultivated roots of Glycyrrhiza uralensis to be used as an alternative medicinal source.

Effect of Schisandrae Fructus on glycyrrhizin content in Kampo extracts containing Glycyrrhizae Radix used clinically in Japan.

Glycyrrhizae Radix is an important crude drug in Japan and is the most frequently prescribed drug in Kampo medicines for the treatment of a wide range of diseases. Glycyrrhizin (GL), the major active ingredient of Glycyrrhizae Radix, has various pharmacological actions but causes adverse effects such as pseudoaldosteronism. In a previous study, the GL content of shoseiryuto was found to be unexpectedly low, and Schisandrae Fructus in shoseiryuto reduced the pH value of the decoction and drastically decreased the extraction efficiency of GL from Glycyrrhizae Radix. In the present study, we investigated the extraction efficiency of GL from Glycyrrhizae Radix in decoctions comprising Glycyrrhizae Radix and five different fruit-derived crude drugs. Among the five fruit-derived crude drugs tested, Schisandrae Fructus markedly decreased both the pH value of the decoction and the extraction efficiency of GL. A comparison of the pH value of the decoction and the GL content of 12 Kampo prescriptions (containing at least Glycyrrhizae Radix and Schisandrae Fructus) showed that the GL content per daily dose was proportional to the compounding amount of Glycyrrhizae Radix, and that the extraction efficiency of GL from Glycyrrhizae Radix was strongly correlated with the pH value of the decoction. In addition, the pH value of the decoction was similar to the pH value documented in interview forms provided by pharmaceutical companies. These results suggested that the GL content in Glycyrrhizae Radix-containing Kampo products can be estimated from both the compounding amounts of Glycyrrhizae Radix and the pH value documented in their interview forms. Knowledge of GL content will help avoid adverse reactions due to Glycyrrhizae Radix.

Evaluation of the safety and efficacy of Glycyrrhiza uralensis root extracts produced using artificial hydroponic-field hybrid cultivation systems II: comparison of serum concentration of glycyrrhetinic acid serum concentration in mice.

To evaluate the safety and efficacy of Glycyrrhiza uralensis root produced using artificial hydroponic and artificial hydroponic-field hybrid cultivation systems, we investigated the pharmacokinetics of a major metabolite of glycyrrhizin (GL), glycyrrhetinic acid (GA). Hot water extracts obtained from the roots of the artificial hydroponic-field hybrid cultivated Glycyrrhiza uralensis were orally administered at a dose of 100 mg/kg as GL in mice and, compared with a commercial crude drug, Glycyrrhizae Radix. The temporal changes in serum GA concentration was found to depend on the GL concentration of the hot-water extracts. When hot-water extracts containing relatively high GL were administered, bimodal peaks appeared. In contrast, a broad single peak was detected when a hot-water extract containing relatively low GL content was administered. These tendencies in the serum GA concentration time course were observed for all samples, regardless of their derivation. Moreover, we compared the pharmacokinetic parameters and found that the Cmax and AUC0-48 values after oral administration of the extracts from Glycyrrhiza uralensis roots produced by the artificial cultivation system are within the range of variation for the commercial crude drugs. These results suggest the possibility that roots of Glycyrrhiza uralensis cultivated by the artificial hydroponic-field hybrid cultivation system can be used in addition to currently available commercial crude drugs produced from wild plant resources.

Mutagenetic and anti-allergic studies for evaluation of extracts of Coptis Rhizome produced by an artificial hydroponic system.

As a part of the investigation of the safety and efficacy of the cultivated Coptis japonica rhizome extracts using an artificial hydroponic cultivation system, the mutagenetic and anti-allergic activities were evaluated. Some extracts of commercial crude drugs of Coptis sp. were also evaluated for the comparison. None of the extracts showed a significant mutagenicity in Salmonella typhimurium TA102 by the Ames tests, but all the extracts showed in S. typhimurium TA98. The extracts of the hydroponically cultivated rhizomes showed anti-allergic activities against contact hypersensitivity as well as those of commercial crude drugs of Coptis sp. These results suggested the potential of the hydroponically cultivated rhizomes as one of the alternative sources for the medicinal usage.

Modification of α-synuclein by lipid peroxidation products derived from polyunsaturated fatty acids promotes toxic oligomerization: its relevance to Parkinson disease.

Recently, toxic α-synuclein oligomer, which can mediate cell-to-cell propagation is suggested to cause sporadic Parkinson disease. α-Synuclein interacts with membrane lipids especially polyunsaturated fatty acids to stabilize its three-dementional structure. Peroxidation of polyunsaturated fatty acids may reduce their affinity to α-synuclein and peroxidation byproducts might modify α-synuclein. 4-Hydroxy-2-nonenal derived from n-6 polyunsaturated fatty acids was reported to modify α-synuclein to produce a toxic oligomer. Moreover, the accumulation of 4-hydroxy-2-nonenal, which could induce oligomeriztion of α-synuclein, was found in parkinsonian brains. Docosahexaenoic acid, an n-3 polyunsaturated fatty acids abundant in the neuronal membrane, was also found to enhance α-synuclein oligomerization; however, the precise details of the chemical reaction involved are unclear. Propanoylated lysine, a specific indicator of docosahexaenoic acid oxidation, was increased in neuronal differentiated human neuroblastoma SH-SY5Y cells overexpressing α-synuclein. α-Synuclein might be modified by the peroxidation products and then, is degraded by the autophagy-lysosome system. In addition, in the cells overexpressing α-synuclein, the mitochondrial electrone transfer chain was found to be inhibited. Accumulation of abnormal α-synuclein modified by lipid radicals derived from polyunsaturated fatty acids may be not only an indicator of brain oxidative stress but also causative of neurodegeneration such as Parkinson disease by impairing mitochondrial function.

Correction to: Comparison of glycyrrhizin content in 25 major kinds of Kampo extracts containing Glycyrrhizae Radix used clinically in Japan.

The article Comparison of glycyrrhizin content in 25 major kinds of Kampo extracts containing Glycyrrhizae Radix used clinically in Japan, written by Mitsuhiko Nose, Momoka Tada, Rika Kojima, Kumiko Nagata, Shinsuke Hisaka, Sayaka Masada, Masato Homma and Takashi Hakamatsuka, was originally published Online First without open access. After publication in volume 71, issue 4, page 711-722 the author decided to opt for Open Choice and to make the article an open access publication. Therefore, the copyright of the article has been changed to

Comparison of glycyrrhizin content in 25 major kinds of Kampo extracts containing Glycyrrhizae Radix used clinically in Japan.

Glycyrrhizae Radix is the most frequently used crude drug in Japan and is prescribed in Kampo medicine for the treatment of a wide range of diseases. The major active ingredient of Glycyrrhizae Radix, glycyrrhizin (GL), has been shown to possess various pharmacological actions, but is also known to cause adverse effects such as pseudoaldosteronism. To avoid the adverse effects of GL, precautions have been indicated on the package inserts of Glycyrrhizae Radix-containing formulas depending on the amount of Glycyrrhizae Radix they contain. However, it remains unknown whether the extraction efficiency of GL from Glycyrrhizae Radix is constant throughout the different combinations of crude drugs in Glycyrrhizae Radix-containing formulas. To confirm the basis of the safety regulation, in this study we comprehensively determined the GL content of 25 major kinds of Kampo extracts compounding Glycyrrhizae Radix. We found that the GL content per daily dosage in all Kampo extracts are generally proportional to the compounding amount of Glycyrrhizae Radix, except in the case of shoseiryuto (Sho-seiryu-To). We also found that Schisandrae Fructus in Sho-seiryu-To decoction caused a lowered pH condition and drastically decreased the extraction efficacy of GL from Glycyrrhizae Radix. Moreover, we were able to confirm that the extraction efficiency of GL from Glycyrrhizae Radix is dependent on the pH value of the extraction solvent. The extraction efficiency of GL in the 25 kinds of Kampo extracts was not constant but it correlates significantly with the pH value of the decoction. Furthermore, the GL contents are well correlated with pseudoaldosteronism incidence data obtained from the Japanese Adverse Drug Event Report (JADER) database on the 25 kinds of Kampo extracts. This suggests that the GL content is a better index to consider to avoid the adverse effects of Glycyrrhizae Radix-containing Kampo formulas.

A mushroom-derived amino acid, ergothioneine, is a potential inhibitor of inflammation-related DNA halogenation.

Myeloperoxidase (MPO)-generated halogenating molecules, such as hypochlorous acid and hypobromous acid (HOBr), in inflammatory regions are postulated to contribute to disease progression. In this study, we showed that ergothioneine (EGT), derived from an edible mushroom, inhibited MPO activity as well as the formation of 8-bromo-2'-deoxyguanosine in vitro. The HOBr scavenging effect of EGT is higher than those of ascorbic acid and glutathione. We initially observed that the administration of Coprinus comatus, an edible mushroom containing a high amount of EGT, inhibited the UV-B-induced inflammatory responses and DNA halogenation, suggesting that EGT is a promising anti-inflammatory agent from mushrooms.

Farnesyltransferase inhibitor, tipifarnib, prevents galactosamine/lipopolysaccharide-induced acute liver failure.

Acute liver failure (ALF) is a fatal syndrome associated with massive hepatocyte death. There is no cure for ALF except liver transplantation. Protein farnesylation is a lipid modification of cysteine residues that is catalyzed by farnesyltransferase (FTase) and has been proposed as an integral component of acute inflammation. Previously, we have demonstrated that FTase inhibitors improve survival in mouse models of endotoxemia and sepsis. Here we studied the effects of FTase inhibitor, tipifarnib, on galactosamine (GalN)/lipopolysaccharide (LPS)-induced ALF. The effects of tipifarnib (10 mg/kg, i.p.) were studied in GalN (400 mg/kg, i.p.)- and LPS (3 µg/kg)-challenged mice by histological and biochemical analyses. Galactosamine/LPS administration caused prominent liver injury characterized by the increased plasma alanine aminotransferase and aspartic aminotransferase levels, leading to significant mortality in mice. Tipifarnib inhibited GalN/LPS-induced caspase 3 activation, inflammatory cytokine production, and c-Jun N-terminal kinase phosphorylation in the liver. On the other hand, tipifarnib upregulated antiapoptotic protein, Bcl-xL, in the liver after GalN/LPS challenge. Tipifarnib also protected primary hepatocytes from GalN/tumor necrosis factor α-induced cell death by inhibiting caspase 3 activation and upregulating antiapoptotic proteins. Galactosamine/LPS-induced liver injury was associated with increased protein farnesylation in the liver. Tipifarnib prevented protein farnesylation in the liver and markedly attenuated liver injury and mortality in GalN/LPS-challenged mice. These results suggest that protein farnesylation is a novel potential molecular target to prevent hepatocyte death and acute inflammatory liver failure in fulminant hepatitis.

Effect of the hot water extract of Artocarpus camansi leaves on 2,4,6-trinitrochlorobenzene (TNCB)-induced contact hypersensitivity in mice.

Medicinal plants with reported anti-inflammatory activity could have the potential use as anti-allergens and inhibitors of allergic contact dermatitis reactions produced by allergens and chemicals. Some species from the genus Artocarpus were reported to have anti-inflammatory activity. In the Philippines one local source is Artocarpus camansi BLANCO (Moraceae), which is utilized as an ingredient of their cuisine, and decoction of leaves is used for diabetes and baths of people with rheumatism. The objective of this study was to evaluate the effect of the hot water extract of A. camansi leaves on contact hypersensitivity (CHS) in mice. Contact hypersensitivity was induced using 2,4,6-trinitrochlorobenzene (TNCB). The results showed that the A. camansi hot water extract exhibited significant activity against the swelling produced during 24 h and 48 h post-challenge. The same responses were observed from the mice that received the kamansi ethanol-precipitate (KEP) and kamansi ethanol precipitate water-soluble (KEPWS) fractions. Since the high molecular mass fraction showed the significant activity, we therefore speculate that the compound responsible might be a polysaccharide and/or glycoprotein. In conclusion, our results suggest that the hot water extract of A. camansi leaves might be an effective natural product to treat allergic contact dermatitis. However, further investigations are required to understand the mechanisms involved.

Lipid hydroperoxide-derived adduction to amino-phospholipid in biomembrane.

Phospholipids such as phosphatidylethanolamine and phosphatidylcholine play crucial roles in the biological system to maintain the cellular environmental condition. Despite that, oxidative stress targets these phospholipids containing polyunsaturated fatty acids and accompanies the oxidized phospholipids. Recent studies have been suggested that oxidized phospholipids have the relationship with inflammation and might induce the atherosclerosis formation by uptake of oxidized LDL through scavenger receptor as ligands. Red blood cells, which have been studied the bilayer model, are also modified by oxidative stress because hemoglobin can mediate and produce the reactive oxygen species, which leads to lipid peroxidation of biomembrane. In these oxidation processes of biomolecules, hexanoylation against phosphatidylethanolamine and phosphatidylserine, which has the primary amine and is the target of this modification, generates the oxidized membrane such as erythrocyte ghosts. This unique structure of phosphatidylethanolamine and phosphatidylserine is possibly the useful biomarker to evaluate the oxidation of biomembrane in vivo using liquid chromatography tandem mass spectrometry and monoclonal antibody.

Role of lipid peroxide in the neurodegenerative disorders.

Nervous system controls all the organs in the living like a symphony. In this chapter, the mechanism of neuronal death in aged is discussed in relation to oxidative stress. Polyunsaturated fatty acid (PUFA) is known to be rich in the membranous component of the neurons and plays an important role in maintaining the neuronal functions. Recent reports revealed that oxidation of omega-3 and omega-6 PUFAs, such as docosahexaenoic acid (DHA) and arachidonic acid (ARA), are potent antioxidant but simultaneously, their oxidation products are potentially toxic. In this chapter, the existence of early oxidation products of PUFA is examined in the samples from neurodegenerative disorders and the cellular model. Accumulation of proteins with abnormal conformation is suggested to induce neuronal death by disturbance of proteolysis and mitochondrial function. The role of lipid peroxide and lipid-derived aldehyde adduct proteins is discussed in relation to brain ageing and age-related neurodegeneration.

Suppressive effect of the hot-water extract of Ficus pseudopalma Blanco leaves on the postprandial increase in blood glucose level in mice.

The use of medicinal plants with anti-diabetic properties continues because of the high cost of diabetes mellitus treatment. In the Bicol region of the Philippines, one local source is the leaves of Ficus pseudopalma Blanco (Philippine fig), which is utilized as an ingredient of their cuisine, and the decoction of its leaves is believed to have a blood-glucose lowering effect. The aim of this study was to evaluate the blood-glucose lowering effect of F. pseudoplama using sugar/carbohydrate-loaded and normoglycemic mice. The results showed that the hot-water extract of the leaves significantly suppressed the increase of blood glucose levels after glucose, maltose and starch loading. On the other hand, the extract did not show any hypoglycemic activity in either fasted or non-fasted mice as compared to the positive control drugs. These results suggest that F. pseudopalma is potentially useful for the management of blood glucose levels in the postprandial condition, as believed in the Bicol region of the Philippines.

Immunohistochemical detection of polyunsaturated fatty acid oxidation markers in acetaminophen-induced liver injury in rats.

To clarfity whether polyunsaturated fatty acid (PUFA) oxidation is involved in the mechanism of acetaminophen (APAP)-induced apoptotic cell death, the production and localization of PUFA oxidation markers N(ε)-propanoyl-modified lysine, N(ε)-hexanoyl-modified lysine, 4-hydroxyhexenal-modified histidine and crotonaldehyde-modified lysine were evaluated in the development of APAP-induced liver injury. The immunoexpression of these markers in the liver was examined up to 24 hr post-APAP intraperitoneal injection in rats (1 g/kg body weight). The histopathological changes in the liver appeared 3 hr after APAP injection and became exacerbated with time. Proapoptotic protein Bax immunoreactivity was first detected in the degenerative hepatocytes 3 hr after the injection and areas positively immunostained for Bax reached a peak level at 6 hr, and then decreased at 12 and 24 hr. There was a significant increase in the TUNEL-positive rate at 12 and 24 hr. Immunohistological expression of all these oxidation markers was first detected in the degenerative hepatocytes 3 hr after the injection, and earlier than the occurrence of hepatocyte apoptosis. Immunohistochemical expression of these markers were observed in almost all degenerative hepatocytes 3-24 hr after APAP injection. Areas positively immunostained for these markers reached a peak level at 6 hr, and then decreased at 12 and 24 hr. The results thus suggest that the generation of PUFA oxidation markers may be the signature of early events preceding the induction of liver cell apoptosis and thus useful for early detection of oxidative stress-related liver cell injury.