a novel vitamin e derivative (tmg) protects gastric mucosal damage induced by ischemia and...

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April 2000 phoresis. The signals were quantified by spot-densitometry, relative to 18s rRNA values. Both CAT-l and Pep'I'l were expressed at equivalent levels in the duodenum and ileum of control animals. ASCT2 expression was approximately two-fold higher in the ileum than in the duodenum. CAT-l expression was not affected by TPN in either duodenum or ileum. Expres- sion of both Pep'TI and ASCT2 was significantly increased in the ileum of TPN fed animals. Pep'I'l transcripts were increased to 296% of control values (p<0.OO5) and ASCT2 transcripts to 220% (p<0.OO5). Expression of both transcripts was not significantly altered in the duodenum (Pep'I'l: 145%, p>0.05; ASCT2: 84%, p>O.4). The results demonstrate that ex- pression of these transporters is not solely dependent on the presence of luminal contents. In these calorifically-maintained animals, up-regulation of Pep'I'l and ASCT2 may reflect adaptational response to maintaining the metabolic requirements of the enterocytes in the absence of luminal nutri- tion. Supported by BBSRC 562 A NOVEL VITAMIN E DERIVATIVE (TMG) PROTECTS GAS- TRIC MUCOSAL DAMAGE INDUCED BY ISCHEMIA AND REPERFUSION. Hiroshi Ichikawa, Hirohisa Takano, Yuji Naito, Norimasa Yoshida, Toshikazu Yoshikawa, Motoharu Kondo, Kyoto Prefectural Univ of Med- icine, Kyoto, Japan. The antioxidative defense effect of a novel vitamin E derivative, 2-(a-D- glucopyranosyl) methyl-2,5,7,8-tetramethylchroman-6-01 (TMG), which has excellent water-solubility (> 1 x 10 3 mglml), was investigated using the reperfusion-induced rat gastric mucosal injury model in vivo. It has been reported that TMG is somewhat located within the membrane surface and acts as a powerful antioxidant by scavenging radicals generated either in the aqueous or in the lipid phase. Clamping the celiac artery for 30 min induced ischemia, and reoxygenation was produced by removal of the clamp 60 min after ischemia. Just before removal of the vascular clamp, TMG at a dose of 0.4 - 4 mglkg dissolved in physiological saline were injected intravenously. The area of gastric mucosal erosion or ulcerative lesion (ulcer index) significantly increased from mean basal levels after 60 min of reperfusion. This ulcer index was significantly inhibited by pre- treatment with TMG. The concentration of thiobarbituric acid-reactive substances (TBA-RS) in the gastric mucosa, an index of lipid peroxidation, were also significantly higher than basal level after 60 min of reperfusion. This increase in TBA-RS in the gastric mucosa after ischemia-reperfusion was inhibited by the pretreatment with TMG. Furthermore, myeloperoxi- dase (MPO) activity in the gastric mucosa, an index of neutrophil infiltra- tion, significantly increased by ischemia reperfusion, and pretreatment of TMG significantly reduced this increase of MPO activity in gastric mucosa. These results suggest that TMG may have protective effects against the oxidative stress in the reperfusion-induced injury models. 563 THE MECHANISM OF GERMINATED BARLEY FOODSTUFF IN ATTENUATING INTESTINAL INFLAMMATION IN COLITIS. Osamu Kanauchi, Akira Andoh, Yoshio Araki, Keiichi Mitsuyama, At- sushi Toyonaga, Michio Sata, Toshifumi Hibi, Toshihiko Iwanaga, Tadao Bamba, Kirin Brewery Co, Takasaki, Japan; Shiga Univ of Med Sci, Ohtsu, Japan; Kurume Univ Sch of Medicine, Kurume, Japan; Keio Univ Sch of Medicine, Tokyo, Japan; Hokkaido Univ, Sch of Veternary Medicine, Sapporo, Japan. Background and Aims: Germinated barley foodstuff (GBF) contains pro- tein and insoluble dietary fiber. We have previously shown in ulcerative colitis patients and colitis model that GBF feeding attenuates mucosal damage by increasing luminal butyrate levels (Aliment Pharmacol Ther 12:1225, 1998). However, the detailed mechanism remains unclear because of its heterogeneous nature. The present study was carried out to (1) evaluate the active ingredient in GBF, (2) to examine its effect on the repair process in colonic inflammation, and (3) to estimate its effect on luminal microflora by using a dextran sulfate sodium (DSS) colitis model. Meth- ods: Colitis was induced by feeding a 0.5 % to 3.5 % DSS containing diet to male SD rats. (1) Active ingredient: GBF was fractionated enzymatically into fiber- and protein-rich fractions. Each fraction was administered to DSS-colitis rats. Clinical signs, cecal short chain fatty acid (SCFA) con- centrations and serum aI-acid glycoprotein (AAG) were determined. (2) Effect on mucosal repair: GBF with or without sulfasalazine (SASP), or SASP alone was administered to rats after the onset of colitis. Seven days after initial treatment, the number of epithelial cells in H&E sections were evaluated morphologically in a blind fashion and serum AAG was deter- mined. (3) Effect on microflora: Bacterial microflora and SCFA measure- ments in the luminal content was performed in colitis rats treated with or without GBF. Results: (1) GBF and GBF-fiber significantly attenuated clinical signs of colitis (p<0.05) and decreased serum AAG (35.7 in GBF, 43.6 in GBF-fiber vs 262.3 in control; p.g/ml p<O.OOl), with a significant increase in cecal butyrate production (20.1 in GBF, 23.4 in GBF-fiber, 2.1 in control p. moll g, p<0.05), while GBF-protein did not. (2)Treatment of GBF alone and GBF with SASP significantly accelerated colonic epithelial repair (76% in GBF, 70% in GBF with SASP vs 41% in control, p<0.05) and improved clinical signs (p<0.05). These effects were more potent than with SASP alone. (3) GBF feeding led to a significant increase in Eubac- terium (8.2 in GBF vs 6.8 in control; log Ig, p<0.05) and a decrease in Bacteroidaceae (p<0.05) were observed. Furthermore, Bifidobacterium was also increased along with a significant increase on butyrate production AGAA73 (p<0.05). Conclusions: These findings suggest that the fiber fraction of GBF may effectively enhance luminal butyrate production by Eubacterium and Bifidobacterium, and thereby accelerate colonic epithelial repair in colitis. 564 A NON-TOXIC HEAT SHOCK PROTEIN 70 INDUCER, GERA- NYLGERANYLACETONE, EFFECTIVELY RESTORES THE HEAT SHOCK RESPONSE IN GASTRIC MUCOSA OF PROTEIN- MALNOURISHED RATS. Kazuhito Rokutan, Tomoko Kawai, Shigetada Teshima, Tsukasa Kawa- hara, Takeshi Nikawa, Kyoichi Kishi, Sch of Medicine, Univ of To- kushima, Tokushima, Japan. Background: Protein malnutrition is inevitable for chronically ill patients with wasting diseases and is linked to cachexia, immune dysfunction, and poor prognosis. Protein-malnourished patients occasionally suffer from severe gastric mucosal damage when confronted with additionally stressful situations. However, it is usually difficult to effectively improve the nutri- tional state due to the underlying diseases. We report here that protein malnutrition inhibits heat shock protein (HSP) 70 induction in rat gastric mucosa and impairs the mucosal defense against stress ulcer. We also examined whether a non-toxic HSP70 inducer, geranylgeranylacetone (GGA), effectively improved the mucosal integrity by stimulating HSP70 induction under protein malnutrition. Methods: The present experiments were approved by the Animal Care Committe, University of Tokushima. Male Wistar rats fed a 5% or a 20% casein diet for 3 weeks were exposed to restraint and water-immersion stress, and the ulcer index was measured. The activation of heat shock factor 1 (HSFl) was examined by gel mobility shift assay with the heat shock element oligonucleotide. The level s of HSP70 mRNA and protein were measured by Northern blotting and Western blotting, respectively. Results and Conclusion: Protein malnutri- tion did not change the HSFllevel in the gastric mucosa, while the protein deficiency attenuated the HSFI activation and inhibited the HSP70 mRNA expression and HSP70 induction after exposure to the stress, leading to aggravate mucosal damage. A single or short-term administration of GGA (200 mglkg twice a day) to the protein-malnourished rats for up to one week failed to stimulate the heat shock response, while administration of GGA for longer than 2 weeks restored the HSP70 induction, and 3 weeks later, the HSP70-inducing capacity of gastric mucosa of the protein- malnourished rats recovered to the level of normally nourished rats. The teatment of protein deficient rats with GGA for 3 weeks induced higher resistance against stress ulcer than that in control rats, suggesting other mechanism besides HSP70-inducing action may be involved in the en- hanced mucosal integrity by GGA. GOA has been widely used in Japan as an antiulcer drug for more than 15 years without any serious adverse effects. Our results suggest that GOA may have a potential benefit for the prevention of stress ulcer in chronically and/or critically ill patients with protein malnutrition. 565 FERMENTATION PRODUCTS OF ALCOHOLIC BEVERAGES MALEIC AND SUCCINIC ACID STIMULATE CCK RELEASE. Karlheinz Kiehne, Jan H. Egberts, Cornelia Wilgus, Stephan Teyssen, Ulrich R. Folsch, Karl-Heinz Herzig, I. Dept of Internal Medicine, Chris- tian-Albrechts-Univ, Kiel, Germany; Univ of Heidelberg, Mannheim, Ger- many. Alcoholic beverages with low ethanol content are powerful stimulants of gastrin release and gastric acid output in humans (Singer et al. 1991). Subsequent studies revealed that fermentation but not distillation produced the stimulators (Teyssen et al. 1997). Recently, maleic and succinic acid have been identified as stimulants of gastric acid secretion from fermented alcoholic beverages (Teyssen et al. 1999). Furthermore, wine and beer significantly increased meal-stimulated pancreatic secretion in humans (Hajnal et al. 1990). Therefore, in this study we investigated the effect of maleic and succinic acid on CCK release using isolated perfused mucosal cells and the neuroendocrine cell line STC-l. Methods: Isolated cells were obtained by incubation of rat prox. small bowel in Ca 2 + -free buffer. After centrifugation, washing, filtration the cells were mixed with Sephadex G50 and transferred into a perfusion apparatus and continously perfused. The neuroendocrine cell line STC-l was seeded (l05 cells/ml) into 6-well plates reaching more than 90% confluence after 3-4 days. CCK determination was measured using a pancreatic bioassay system. Maleic and succinic acid did not affect amylase secretion from isolated acini. Results: In isolated duo- denal cells, maleic and succinic acid dose-dependently stimulated CCK release from 2,7:t0,3 to B,I:tl,7 and 27,1:t3,4pM at lmM, an amount, which is found in finished beer (Piendl 1980). At lOOnM succinic but not maleic acid still stimulated CCK release to 8±0,9pM. In addition, in the neuroendocrine cell line STC-I maleic and succinic acid dose-dependently stimulated CCK release from 3,1:to,3 to 8,9:t 1,5 and Il,7:t2,3pM at 100nM, respectively. Pretreatment of the cells with the voltage-gated L-type calcium channel blocker diltiazem significantly inhibited maleic and succinic acid stimulated CCK release. Conclusion: These data identify maleic and succinic acid as potent direct stimuli of CCK release via increases in intracellular calcium mediated by voltage-gated L-type cal- cium channels.

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Page 1: A novel vitamin E derivative (TMG) protects gastric mucosal damage induced by ischemia and reperfusion

April 2000

phoresis. The signals were quantified by spot-densitometry, relative to 18srRNA values. Both CAT-l and Pep'I'l were expressed at equivalent levelsin the duodenum and ileum of control animals. ASCT2 expression wasapproximately two-fold higher in the ileum than in the duodenum. CAT-lexpression was not affected by TPN in either duodenum or ileum. Expres­sion of both Pep'TI and ASCT2 was significantly increased in the ileum ofTPN fed animals. Pep'I'l transcripts were increased to 296% of controlvalues (p<0.OO5) and ASCT2 transcripts to 220% (p<0.OO5). Expressionof both transcripts was not significantly altered in the duodenum (Pep'I'l:145%, p>0.05; ASCT2: 84%, p>O.4). The results demonstrate that ex­pression of these transporters is not solely dependent on the presence ofluminal contents. In these calorifically-maintained animals, up-regulationof Pep'I'l and ASCT2 may reflect adaptational response to maintaining themetabolic requirements of the enterocytes in the absence of luminal nutri­tion. Supported by BBSRC

562A NOVEL VITAMIN E DERIVATIVE (TMG) PROTECTS GAS­TRIC MUCOSAL DAMAGE INDUCED BY ISCHEMIA ANDREPERFUSION.Hiroshi Ichikawa, Hirohisa Takano, Yuji Naito, Norimasa Yoshida,Toshikazu Yoshikawa, Motoharu Kondo, Kyoto Prefectural Univ of Med­icine, Kyoto, Japan.

The antioxidative defense effect of a novel vitamin E derivative, 2-(a-D­glucopyranosyl) methyl-2,5,7,8-tetramethylchroman-6-01 (TMG), whichhas excellent water-solubility (> 1 x 103 mglml), was investigated using thereperfusion-induced rat gastric mucosal injury model in vivo. It has beenreported that TMG is somewhat located within the membrane surface andacts as a powerful antioxidant by scavenging radicals generated either inthe aqueous or in the lipid phase. Clamping the celiac artery for 30 mininduced ischemia, and reoxygenation was produced by removal of theclamp 60 min after ischemia. Just before removal of the vascular clamp,TMG at a dose of 0.4 - 4 mglkg dissolved in physiological saline wereinjected intravenously. The area of gastric mucosal erosion or ulcerativelesion (ulcer index) significantly increased from mean basal levels after 60min of reperfusion. This ulcer index was significantly inhibited by pre­treatment with TMG. The concentration of thiobarbituric acid-reactivesubstances (TBA-RS) in the gastric mucosa, an index of lipid peroxidation,were also significantly higher than basal level after 60 min of reperfusion.This increase in TBA-RS in the gastric mucosa after ischemia-reperfusionwas inhibited by the pretreatment with TMG. Furthermore, myeloperoxi­dase (MPO) activity in the gastric mucosa, an index of neutrophil infiltra­tion, significantly increased by ischemia reperfusion, and pretreatment ofTMG significantly reduced this increase of MPO activity in gastric mucosa.These results suggest that TMG may have protective effects against theoxidative stress in the reperfusion-induced injury models.

563THE MECHANISM OF GERMINATED BARLEY FOODSTUFF INATTENUATING INTESTINAL INFLAMMATION IN COLITIS.Osamu Kanauchi, Akira Andoh, Yoshio Araki, Keiichi Mitsuyama, At­sushi Toyonaga, Michio Sata, Toshifumi Hibi, Toshihiko Iwanaga, TadaoBamba, Kirin Brewery Co, Takasaki, Japan; Shiga Univ of Med Sci, Ohtsu,Japan; Kurume Univ Sch of Medicine, Kurume, Japan; Keio Univ Sch ofMedicine, Tokyo, Japan; Hokkaido Univ, Sch of Veternary Medicine,Sapporo, Japan.

Background and Aims: Germinated barley foodstuff (GBF) contains pro­tein and insoluble dietary fiber. We have previously shown in ulcerativecolitis patients and colitis model that GBF feeding attenuates mucosaldamage by increasing luminal butyrate levels (Aliment Pharmacol Ther12:1225, 1998). However, the detailed mechanism remains unclear becauseof its heterogeneous nature. The present study was carried out to (1)evaluate the active ingredient in GBF, (2) to examine its effect on the repairprocess in colonic inflammation, and (3) to estimate its effect on luminalmicroflora by using a dextran sulfate sodium (DSS) colitis model. Meth­ods: Colitis was induced by feeding a 0.5 % to 3.5 % DSS containing dietto male SD rats. (1) Active ingredient: GBF was fractionated enzymaticallyinto fiber- and protein-rich fractions. Each fraction was administered toDSS-colitis rats. Clinical signs, cecal short chain fatty acid (SCFA) con­centrations and serum aI-acid glycoprotein (AAG) were determined. (2)Effect on mucosal repair: GBF with or without sulfasalazine (SASP), orSASP alone was administered to rats after the onset of colitis. Seven daysafter initial treatment, the number of epithelial cells in H&E sections wereevaluated morphologically in a blind fashion and serum AAG was deter­mined. (3) Effect on microflora: Bacterial microflora and SCFA measure­ments in the luminal content was performed in colitis rats treated with orwithout GBF. Results: (1) GBF and GBF-fiber significantly attenuatedclinical signs of colitis (p<0.05) and decreased serum AAG (35.7 in GBF,43.6 in GBF-fiber vs 262.3 in control; p.g/ml p<O.OOl), with a significantincrease in cecal butyrate production (20.1 in GBF, 23.4 in GBF-fiber, 2.1in control p. moll g, p<0.05), while GBF-protein did not. (2)Treatment ofGBF alone and GBF with SASP significantly accelerated colonic epithelialrepair (76% in GBF, 70% in GBF with SASP vs 41% in control, p<0.05)and improved clinical signs (p<0.05). These effects were more potent thanwith SASP alone. (3) GBF feeding led to a significant increase in Eubac­terium (8.2 in GBF vs 6.8 in control; log Ig, p<0.05) and a decrease inBacteroidaceae (p<0.05) were observed. Furthermore, Bifidobacteriumwas also increased along with a significant increase on butyrate production

AGAA73

(p<0.05). Conclusions: These findings suggest that the fiber fraction ofGBF may effectively enhance luminal butyrate production by Eubacteriumand Bifidobacterium, and thereby accelerate colonic epithelial repair incolitis.

564

A NON-TOXIC HEAT SHOCK PROTEIN 70 INDUCER, GERA­NYLGERANYLACETONE, EFFECTIVELY RESTORES THEHEAT SHOCK RESPONSE IN GASTRIC MUCOSA OF PROTEIN­MALNOURISHED RATS.Kazuhito Rokutan, Tomoko Kawai, Shigetada Teshima, Tsukasa Kawa­hara, Takeshi Nikawa, Kyoichi Kishi, Sch of Medicine, Univ of To­kushima, Tokushima, Japan.

Background: Protein malnutrition is inevitable for chronically ill patientswith wasting diseases and is linked to cachexia, immune dysfunction, andpoor prognosis. Protein-malnourished patients occasionally suffer fromsevere gastric mucosal damage when confronted with additionally stressfulsituations. However, it is usually difficult to effectively improve the nutri­tional state due to the underlying diseases. We report here that proteinmalnutrition inhibits heat shock protein (HSP) 70 induction in rat gastricmucosa and impairs the mucosal defense against stress ulcer. We alsoexamined whether a non-toxic HSP70 inducer, geranylgeranylacetone(GGA), effectively improved the mucosal integrity by stimulating HSP70induction under protein malnutrition. Methods: The present experimentswere approved by the Animal Care Committe, University of Tokushima.Male Wistar rats fed a 5% or a 20% casein diet for 3 weeks were exposedto restraint and water-immersion stress, and the ulcer index was measured.The activation of heat shock factor 1 (HSFl) was examined by gel mobilityshift assay with the heat shock element oligonucleotide. The level s ofHSP70 mRNA and protein were measured by Northern blotting andWestern blotting, respectively. Results and Conclusion: Protein malnutri­tion did not change the HSFllevel in the gastric mucosa, while the proteindeficiency attenuated the HSFI activation and inhibited the HSP70 mRNAexpression and HSP70 induction after exposure to the stress, leading toaggravate mucosal damage. A single or short-term administration of GGA(200 mglkg twice a day) to the protein-malnourished rats for up to oneweek failed to stimulate the heat shock response, while administration ofGGA for longer than 2 weeks restored the HSP70 induction, and 3 weekslater, the HSP70-inducing capacity of gastric mucosa of the protein­malnourished rats recovered to the level of normally nourished rats. Theteatment of protein deficient rats with GGA for 3 weeks induced higherresistance against stress ulcer than that in control rats, suggesting othermechanism besides HSP70-inducing action may be involved in the en­hanced mucosal integrity by GGA. GOA has been widely used in Japan asan antiulcer drug for more than 15 years without any serious adverseeffects. Our results suggest that GOA may have a potential benefit for theprevention of stress ulcer in chronically and/or critically ill patients withprotein malnutrition.

565

FERMENTATION PRODUCTS OF ALCOHOLIC BEVERAGESMALEIC AND SUCCINIC ACID STIMULATE CCK RELEASE.Karlheinz Kiehne, Jan H. Egberts, Cornelia Wilgus, Stephan Teyssen,Ulrich R. Folsch, Karl-Heinz Herzig, I. Dept of Internal Medicine, Chris­tian-Albrechts-Univ, Kiel, Germany; Univ of Heidelberg, Mannheim, Ger­many.

Alcoholic beverages with low ethanol content are powerful stimulants ofgastrin release and gastric acid output in humans (Singer et al. 1991).Subsequent studies revealed that fermentation but not distillation producedthe stimulators (Teyssen et al. 1997). Recently, maleic and succinic acidhave been identified as stimulants of gastric acid secretion from fermentedalcoholic beverages (Teyssen et al. 1999). Furthermore, wine and beersignificantly increased meal-stimulated pancreatic secretion in humans(Hajnal et al. 1990). Therefore, in this study we investigated the effect ofmaleic and succinic acid on CCK release using isolated perfused mucosalcells and the neuroendocrine cell line STC-l. Methods: Isolated cells wereobtained by incubation of rat prox. small bowel in Ca2+ -free buffer. Aftercentrifugation, washing, filtration the cells were mixed with Sephadex G50and transferred into a perfusion apparatus and continously perfused. Theneuroendocrine cell line STC-l was seeded (l05 cells/ml) into 6-well platesreaching more than 90% confluence after 3-4 days. CCK determination wasmeasured using a pancreatic bioassay system. Maleic and succinic acid didnot affect amylase secretion from isolated acini. Results: In isolated duo­denal cells, maleic and succinic acid dose-dependently stimulated CCKrelease from 2,7:t0,3 to B,I:tl,7 and 27,1:t3,4pM at lmM, an amount,which is found in finished beer (Piendl 1980). At lOOnM succinic but notmaleic acid still stimulated CCK release to 8±0,9pM. In addition, in theneuroendocrine cell line STC-I maleic and succinic acid dose-dependentlystimulated CCK release from 3,1:to,3 to 8,9:t 1,5 and Il,7:t2,3pM at100nM, respectively. Pretreatment of the cells with the voltage-gatedL-type calcium channel blocker diltiazem significantly inhibited maleicand succinic acid stimulated CCK release. Conclusion: These data identifymaleic and succinic acid as potent direct stimuli of CCK release viaincreases in intracellular calcium mediated by voltage-gated L-type cal­cium channels.