RESUMEN
The operating principle of conventional water electrolysis using heterogenous catalysts has been primarily focused on the unidirectional charge transfer within the heterostructure. Herein, multidirectional charge transfer concept has been adopted within heterostructured catalysts to develop an efficient and robust bifunctional water electrolysis catalyst, which comprises perovskite oxides (La0.5Sr0.5CoO3-δ, LSC) and potassium ion-bonded MoSe2 (K-MoSe2). The complementary charge transfer from LSC and K to MoSe2 endows MoSe2 with the electron-rich surface and increased electrical conductivity, which improves the hydrogen evolution reaction (HER) kinetics. Excellent oxygen evolution reaction (OER) kinetics of LSC/K-MoSe2 is also achieved, surpassing that of the noble metal (IrO2), attributed to the enhanced adsorption capability of surface-based oxygen intermediates of the heterostructure. Consequently, the water electrolysis efficiency of LSC/K-MoSe2 exceeds the performance of the state-of-the-art Pt/C||IrO2 couple. Furthermore, LSC/K-MoSe2 exhibits remarkable chronopotentiometric stability over 2,500 h under a high current density of 100 mA cm-2.
RESUMEN
We evaluated the effect of biofeedback therapy (BFT) on anorectal function after stoma closure when administered during the interval of temporary stoma after sphincter-preserving surgery for rectal cancer.Impaired anorectal function is common after lower anterior resections, though no specific treatment options are currently available to prevent this adverse outcome.Fifty-six patients who underwent neoadjuvant chemoradiation therapy after sphincter-preserving surgery with temporary stoma were randomized into 2 groups: group 1 (received BFT during the temporary stoma period) and group 2 (did not receive BFT). To evaluate anorectal function, anorectal manometry was performed in all patients and subjective symptoms were evaluated using the Cleveland Clinic Incontinence Score. The present study is a report at 6 months after rectal resection.Forty-seven patients, including 21 in group 1 and 26 in group 2, were evaluated by anorectal manometry. Twelve patients (57.1%) in group 1 and 13 patients (50%) in group 2 were scored above 9 points of Cleveland Clinic Incontinence Score, which is the reference value for fecal incontinence (Pâ=â0.770). With time, there was a significant difference (Pâ=â0.002) in the change of mean resting pressure according to time sequence between the BFT and control groups.BFT during the temporary stoma interval had no effect on preventing anorectal dysfunction after temporary stoma reversal at 6 months after rectal resection. However, BFT might be helpful for maintaining resting anal sphincter tone (NCT01661829).
Asunto(s)
Adenocarcinoma/cirugía , Canal Anal/fisiopatología , Biorretroalimentación Psicológica , Estreñimiento/prevención & control , Incontinencia Fecal/prevención & control , Neoplasias del Recto/cirugía , Adenocarcinoma/terapia , Anciano , Quimioradioterapia Adyuvante , Estreñimiento/etiología , Defecación , Enterostomía , Incontinencia Fecal/etiología , Femenino , Humanos , Masculino , Manometría , Persona de Mediana Edad , Terapia Neoadyuvante , Tratamientos Conservadores del Órgano/efectos adversos , Estudios Prospectivos , Neoplasias del Recto/terapiaRESUMEN
PURPOSE: We investigated the relationships between biomarkers related to endoplasmic reticulum stress proteins (glucose-regulated protein of molecular mass 78 [GRP78] and Cripto-1 [teratocarcinoma-derived growth factor 1 protein]), pathologic response, and prognosis in locally advanced rectal cancer. MATERIALS AND METHODS: All clinical stage II and III rectal cancer patients received 50.4 Gy over 5.5 weeks, plus 5-fluorouracil (400 mg/m(2)/day) and leucovorin (20 mg/m(2)/day) bolus on days 1 to 5 and 29 to 33, and surgery was performed at 7 to 10 weeks after completion of all therapies. Expression of GRP78 and Cripto-1 proteins was determined by immunohistochemistry and was assessed in 101 patients with rectal cancer treated with neoadjuvant chemoradiotherapy (CRT). RESULTS: High expression of GRP78 and Cripto-1 proteins was observed in 86 patients (85.1%) and 49 patients (48.5%), respectively. Low expression of GRP78 protein was associated with a significantly high rate of down staging (80.0% vs. 52.3%, respectively; p=0.046) and a significantly low rate of recurrence (0% vs. 33.7%, respectively; p=0.008) compared with high expression of GRP78 protein. Mean recurrence-free survival according to GRP78 expression could not be estimated because the low expression group did not develop recurrence events but showed a significant correlation with time to recurrence, based on the log rank method (p=0.007). GRP78 also showed correlation with overall survival, based on the log rank method (p=0.045). CONCLUSION: GRP78 expression is a predictive and prognostic factor for down staging, recurrence, and survival in rectal cancer patients treated with 5-fluorouracil and leucovorin neoadjuvant CRT.
Asunto(s)
Quimioradioterapia Adyuvante/métodos , Proteínas Ligadas a GPI/metabolismo , Proteínas de Choque Térmico/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Terapia Neoadyuvante , Proteínas de Neoplasias/metabolismo , Neoplasias del Recto/metabolismo , Neoplasias del Recto/terapia , Anciano , Biomarcadores de Tumor , Chaperón BiP del Retículo Endoplásmico , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/uso terapéutico , Proteínas Ligadas a GPI/genética , Proteínas de Choque Térmico/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Laparoscopía , Leucovorina/administración & dosificación , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , PronósticoRESUMEN
OBJECTIVE: To analyze the gas generated from the transurethral resection of the prostate (TURP) and transurethral resection of bladder (TURB) tumor. METHODS: Thirty-six smoke samples were collected from a continuous irrigation suction system during the TURP and the TURB. Then, they were subdivided into 2 groups: the group I (n = 18; gases generated from the TURP) and the group II (n = 18; gases generated from the TURB). We performed qualitative and quantitative analysis of the samples on gas chromatography/mass spectrometry. RESULTS: A more diverse type of gas was generated from the TURB as compared with the TURP. A further quantitative analysis was performed for 7 of 16 gases and 13 of 39 gases in the group I and group II, respectively. This showed that there was no significant difference in the concentration of propylene (propylene: 148.36 ± 207.72 ug/g vs 96.956 ± 135.138 ug/g) and 1-pentene (5137.08 ± 2935.48 ug/g vs 4478.259 ± 5787.351 ug/g) between the TURP and the TURB (P >.05). CONCLUSION: Our results showed that 39 and 16 types of gases were generated from the TURB and the TURP, respectively. There were differences in the types of gases between benign hypertrophic prostate and malignant bladder tumor tissues. This indicates that electrosurgery of malignant tissue is possibly more hazardous to those who are involved in the surgical operation.
Asunto(s)
Electrocirugia , Gases/química , Hidrocarburos/análisis , Exposición Profesional , Hiperplasia Prostática/cirugía , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Anciano de 80 o más Años , Contaminantes Ocupacionales del Aire , Alquenos/análisis , Cromatografía de Gases y Espectrometría de Masas , Gases/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Quirófanos , Humo/efectos adversos , Resección Transuretral de la PróstataRESUMEN
Rectal burns caused by hot water enema have been reported only occasionally and the majority of them were treated in a conservative manner. Although intractable rectal stricture caused by rectal burn is rare, it may be treated by endoscopic intervention or surgery. A 52-year-old woman who had used various methods of enema to treat her chronic constipation eventually undertook a hot water enema herself. After that, anal pain and constipation became aggravated prompting her to visit our clinic. Although various nonoperative treatments including endoscopic stenting were performed, her obstructive symptom did not improve and endoscopic findings had not changed. Hence, we performed a laparoscopic proctosigmoidectomy and transanal coloanal anastomosis with ileal diversion to treat the disease, and as a result, her obstructive symptom improved well. Corrective surgery such as resection of involved segment with anastomosis may be beneficial in relieving obstructive symptoms of an intractable rectal stricture caused by hot water enema.
RESUMEN
Berberine has a wide range of biochemical and pharmacologic effects, including antitumor activity, but the mechanisms involved in berberine-induced apoptosis remain unclear. The purpose of the present study was to investigate the changes in oxidative stress and endoplasmic reticulum (ER)-related molecules, which are closely associated with cell death-signaling transduction pathways, in human glioblastoma T98G cells treated with berberine. Berberine significantly decreased the cell viability of T98G cells in a dose-dependent manner. Berberine increased the production of reactive oxygen species (ROS) and level of intracellular Ca(2+). Berberine induced ER stress as evidenced by the detection of ER stress-associated molecules such as phosphorylated protein kinase-like ER kinase, eukaryotic translation initiation factor-2α, glucose-regulated protein 78/immunoglobulin heavy chain-binding protein, and CCAAT/enhancer-binding protein (C/EBP)-homologous protein/growth arrest and DNA damage-inducible gene 153, which was associated with the activation of caspase-3. Furthermore, the administration of the antioxidants, N-acetylcysteine and glutathione, reversed berberine-induced apoptosis. Berberine also markedly enhanced apoptosis in T98G cells through the induction of a higher ratio of Bax/Bcl-2 proteins, disruption of the mitochondrial membrane potential, activation of caspase-9 and -3, and cleavage of the poly(ADP-ribose) polymerase (PARP). The inhibition of ER stress using salubrinal led to an increased the level of Bcl-2, whereas the level of Bax, cleavage of procaspase-9 and -3, and PARP were decreased when compared with cells treated with berberine alone, indicating that berberine-induced apoptosis is associated with mitochondrial dysfunction. These results demonstrate that berberine induces apoptosis via ER stress through the elevation of ROS and mitochondrial-dependent pathway in human glioblastoma T98G cells.
Asunto(s)
Apoptosis/efectos de los fármacos , Berberina/farmacología , Retículo Endoplásmico/efectos de los fármacos , Glioblastoma/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/metabolismo , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/uso terapéutico , Antioxidantes/farmacología , Berberina/uso terapéutico , Calcio/metabolismo , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Cinamatos/farmacología , Relación Dosis-Respuesta a Droga , Retículo Endoplásmico/metabolismo , Glioblastoma/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Extractos Vegetales/uso terapéutico , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/efectos de los fármacos , Tiourea/análogos & derivados , Tiourea/farmacología , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Ebselen, an organoselenium compound that acts as a glutathione peroxidase mimetic, has been demonstrated to possess antioxidant and anti-inflammatory activities. However, the molecular mechanism underlying this effect is not fully understood in auditory cells. The purpose of the present study is to investigate the protective effect of ebselen against cisplatin-induced toxicity in HEI-OC1 auditory cells, organotypic cultures of cochlear explants from two-day postnatal rats (P(2)) and adult Balb/C mice. Pretreatment with ebselen ameliorated apoptotic death induced by cisplatin in HEI-OC1 cells and organotypic cultures of Corti's organ. Ebselen pretreatment also significantly suppressed cisplatin-induced increases in intracellular reactive oxygen species (ROS), intracellular reactive nitrogen species (RNS) and lipid peroxidation levels. Ebselen dose-dependently increased the expression level of an antioxidant response element (ARE)-luciferase reporter in HEI-OC1 cells through the translocation of Nrf2 into the nucleus. Furthermore, we found that pretreatment with ebselen significantly restored Nrf2 function, whereas it ameliorated the cytotoxicity of cisplatin in cells transfectants with either a pcDNA3.1 (control) or a DN-Nrf2 (dominant-negative) plasmid. We also observed that Nrf2 activation by ebselen increased the expression of phase II antioxidant genes, including heme oxygenase (HO-1), NAD(P)H:quinine oxidoreductase, and gamma-glutamylcysteine synthetase (gamma-GCS). Treatment with ebselen resulted in an increased expression of HO-1 and intranuclear Nrf2 in hair cells of organotypic cultured cochlea. After intraperitoneal injection with cisplatin, auditory brainstem responses (ABRs) threshold was measured on 8th day in Balb/C mice. ABR threshold shift was marked occurred in mice injected with cisplatin (16 mg/kg, n=5; Click and 8-kHz stimuli, p<0.05; 4, 16 and 32 kHz, p<0.01), whereas that of animal group which was treated with cisplatin and ebselen was not significantly changed. These results suggest that ebselen activates the Nrf2-ARE signaling pathway, which ultimately prevents free radical stresses from cisplatin and further contributes to protect auditory sensory hair cells from free radicals produced by cisplatin.
Asunto(s)
Azoles/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Fármacos Neuroprotectores/farmacología , Órgano Espiral/efectos de los fármacos , Órgano Espiral/metabolismo , Compuestos de Organoselenio/farmacología , Animales , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Línea Celular Transformada , Cisplatino/toxicidad , Potenciales Evocados Auditivos del Tronco Encefálico/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Genes Reporteros , Isoindoles , Peroxidación de Lípido/efectos de los fármacos , Luciferasas/genética , Ratones , Ratones Endogámicos BALB C , Factor 2 Relacionado con NF-E2/genética , Técnicas de Cultivo de Órganos , Órgano Espiral/citología , Fenoles/metabolismo , Extractos Vegetales/genética , Extractos Vegetales/metabolismo , Especies Reactivas de Oxígeno/metabolismo , TransfecciónRESUMEN
AIM OF THE STUDY: Sasim, a traditional prescription composed of seven herbal mixtures, has been widely used as an oriental medicine for the treatment of cerebral infarction in Korea. However, the regulatory mechanisms by which the formula affects immune processing in cerebral infarction patients remain unknown. MATERIALS AND METHODS: The levels of secretory protein of tumor necrosis factor (TNF)-alpha were determined in both THP-1 differentiated macrophage-like (THP-1/M) cells and Peripheral blood mononuclear cells (PBMCs) from cerebral infarction patients. Also, the levels of protein and mRNA of TNF-alpha and heme oxygenase-1 (HO-1) were detected in THP-1/M cells under our experimental condition. RESULTS: Sasim markedly suppressed lipopolysaccharide (LPS)-induced TNF-alpha at the levels of secretory protein and mRNA in both PBMCs from cerebral infarction patients and THP-1/M cells. Interestingly, Sasim strongly induced HO-1, the rate-limiting enzyme of heme catabolism, at both the protein and mRNA levels in THP-1/M cells. Treatment with tin protoporphyrin IX (SnPP), an inhibitor of the catalytic activity of HO, significantly abolished the suppressive effect of Sasim on LPS-induced TNF-a production in THP-1/M cells. CONCLUSIONS: These data indicate that Sasim may be beneficial in the cessation of inflammatory processes associated with cerebral infarction through the induction of HO-1 expression.
Asunto(s)
Infarto Cerebral/tratamiento farmacológico , Hemo-Oxigenasa 1/efectos de los fármacos , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Adulto , Anciano , Línea Celular , Infarto Cerebral/metabolismo , Inducción Enzimática/efectos de los fármacos , Femenino , Hemo-Oxigenasa 1/metabolismo , Humanos , Corea (Geográfico) , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Medicina Tradicional de Asia Oriental , Persona de Mediana Edad , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Hibiscus sabdariffa L., a tropical beverage material and medical herb, is used commonly as in folk medicines against hypertension, pyrexia, inflammation, liver disorders, and obesity. This report was designed to investigate the inhibitory mechanisms of hibiscus extract on adipocyte differentiation in 3T3-L1 preadipocytes. The possible inhibitory pathways that regulate the adipocyte differentiation contain the adipogenic transcription factors, C/EBPalpha and PPARgamma, PI3-kinase, and MAPK pathway. In this study, we examined whether hibiscus extract affected the adipogenesis via these three pathways. To differentiate preadipocyte in adipocyte, confluent 3T3-L1 preadipocytes were treated with the hormone mixture including isobutylmethylxanthine, dexamethasone, and insulin (MDI). Hibiscus extract inhibited significantly the lipid droplet accumulation by MDI in a dose-dependent manner and attenuated dramatically the protein and mRNA expressions of adipogenic transcriptional factors, C/EBPalpha and PPARgamma, during adipogenesis. The increase of phosphorylation and expression of PI3-K/Akt during adipocytic differentiation was markedly inhibited by treatment with hibiscus extract or PI3-K inhibitors. Furthermore, the phosphorylation and expression of MEK-1/ERK known to regulate the early phase of adipogenesis were clearly decreased with the addition of hibiscus extract. Taken together, this report suggests that hibiscus extract inhibits the adipocyte differentiation through the modulation of PI3-K/Akt and ERK pathway that play pivotal roles during adipogenesis.
Asunto(s)
Adipocitos/efectos de los fármacos , Hibiscus/química , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Inhibidores de las Quinasa Fosfoinosítidos-3 , Transducción de Señal/efectos de los fármacos , Células 3T3 , Adipocitos/fisiología , Adipogénesis/efectos de los fármacos , Animales , Compuestos Azo , Western Blotting , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colorantes , Relación Dosis-Respuesta a Droga , Metabolismo de los Lípidos/efectos de los fármacos , Ratones , Proteínas Quinasas Activadas por Mitógenos/biosíntesis , Proteínas Quinasas Activadas por Mitógenos/fisiología , Fosfatidilinositol 3-Quinasas/biosíntesis , Fosfatidilinositol 3-Quinasas/fisiología , Fosforilación , Extractos Vegetales/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Sasim, a prescription composed of seven herbal mixtures, has been widely used for the treatment of cerebral infarction as an oriental medicine in Korea. However, the mechanisms by which the formula affects on the production of pro-inflammatory cytokines in cerebral infarct patients remain unknown yet. The levels of secretory protein and mRNA of pro-inflammatory cytokines, including tumor necrosis factor (TNF)-alpha, interlukin (IL)-1beta, and IL-6, were significantly increased in both THP-1 differentiated macrophage-like cells (T/M) and peripheral blood mononuclear cells (PBMCs) from cerebral infarct patients at 24h after stimulation with phytohemagglutinin (PHA) (p<0.05). However, pretreatment of Sasim strongly suppressed the secretion of pro-inflammatory cytokines in PHA-stimulated T/M cells and PBMCs. Moreover, Sasim significantly suppressed the transcriptional levels of pro-inflammatory cytokines in PHA-stimulated THP-1/M cells. These data indicate that Sasim may be beneficial in the cessation of inflammatory processes of cerebral infarction through suppression on the production of pro-inflammatory cytokines via inhibition of mRNA expression.
Asunto(s)
Antiinflamatorios/farmacología , Infarto Cerebral/sangre , Citocinas/biosíntesis , Leucocitos Mononucleares/metabolismo , Monocitos/metabolismo , Extractos Vegetales/farmacología , Línea Celular , Citocinas/genética , Humanos , Técnicas In Vitro , Corea (Geográfico) , Activación de Macrófagos , Medicina Tradicional de Asia Oriental , Fitohemaglutininas/farmacología , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
We studied the effect of 4-acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol (AETD) isolated from Isaria japonica, one of the most popular Chinese fungal medicines, on the induction of apoptosis in rat bladder carcinoma NBT-II cells. AETD was cytotoxic to NBT-II cells, and this cytotoxic effect appears to be attributed to its induction of apoptotic cell death, as AETD induced nuclear morphological changes and internucleosomal DNA fragmentation, and increased the proportion of hypodiploid cells and activity of caspase-3. AETD treatment also decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the pro-apoptotic protein Bax. These results provide important information in understanding the mechanism(s) of AETD-induced apoptosis.
Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Tricotecenos/farmacología , Neoplasias de la Vejiga Urinaria/patología , Animales , Carcinoma/metabolismo , Caspasa 3 , Caspasas/metabolismo , Línea Celular Tumoral/efectos de los fármacos , Fragmentación del ADN , ADN de Neoplasias/análisis , Microscopía Fluorescente , Ratas , Neoplasias de la Vejiga Urinaria/metabolismo , Proteína X Asociada a bcl-2RESUMEN
Scopoletin (1-50 microg/ml) inhibited the release of PGE2, TNF-alpha, IL-1beta and IL-6 and suppressed the expression of COX-2 in a concentration-dependent manner. These results suggest that scopoletin might suppress the production of such pro-inflammatory cytokines and exert inhibitory activity on LPS-induced PGE2 production through the depression of COX-2 expression.
Asunto(s)
Antiinflamatorios/farmacología , Artemisia , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Fitoterapia , Escopoletina/farmacología , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/uso terapéutico , Línea Celular/efectos de los fármacos , Ciclooxigenasa 2 , Dinoprostona/metabolismo , Relación Dosis-Respuesta a Droga , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Isoenzimas/metabolismo , Lipopolisacáridos , Ratones , Prostaglandina-Endoperóxido Sintasas/metabolismo , Escopoletina/administración & dosificación , Escopoletina/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The inhibitory effects of tanshinone IIA, a diterpene isolated from Salvia miltiorrhiza root, on the production of nitric oxide (NO), interleukin-1beta (IL-1beta), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), and the expression of inducible nitric oxide synthase (iNOS) were investigated in activated RAW 264.7 cells. This compound markedly inhibited the production of NO, IL-1beta and TNF-alpha, and suppressed the expression of iNOS in a dose-dependent manner. These results suggest that the traditional use of S. miltiorrhiza as an anti-inflammatory herbal medicine may be explained, in part, by the inhibition of NO, IL-1beta, IL-6 and TNF-alpha production, and expression of iNOS.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Óxido Nítrico Sintasa/biosíntesis , Fenantrenos/farmacología , Fitoterapia , Salvia miltiorrhiza , Abietanos , Animales , Antiinflamatorios no Esteroideos/química , Relación Dosis-Respuesta a Droga , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico Sintasa/efectos de los fármacos , Óxido Nítrico Sintasa de Tipo II , Fenantrenos/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
The root of Paeonia suffruticosa ANDREWS is an important Chinese crude drug used in many traditional prescriptions. 1,2,3,4,6-Penta-O-galloyl-beta-D-glucose (PGG), a major component of this crude drug, has been shown to possess potent anti-oxidant, anti-mutagenic and anti-proliferative effects. In the present study, we examined the effect of PGG on the expression of neuronal heme oxygenase-1 (HO-1), an inducible stress protein that degrades heme to the neuroactive molecule, carbon monoxide and the anti-oxidant, biliverdin. Exposure of Neuro 2A cells to PGG (10-50 microM) resulted in a concentration- and time-dependent induction of HO-1 mRNA, and protein expressions and heme oxygenase activity. Interestingly, pretreatment of the neuronal cells with PGG resulted in enhanced cellular resistance to hydrogen peroxide. This cytoprotective effect was reversed by zinc protoporphyrin IX, an inhibitor of heme oxygenase. This study showed that PGG could protect neuronal cells from oxidative stress via the induction of HO-1 gene expression.