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ABSTRACT: Increasing incidence of small intestinal ulcers associated with nonsteroidal anti-inflammatory drugs (NSAIDs) has become a topic with recent advances of endoscopic technology. However, the pathogenesis and therapy are not fully understood. The aim of this study is to examine the effect of Rikkunshito (TJ-43), a traditional herbal medicine, on expression of HSP60 and cytoprotective ability in small intestinal cell line (IEC-6). Effect of TJ-43 on HSP60 expression in IEC-6 cells was evaluated by immunoblot analysis. The effect of TJ-43 on cytoprotective abilities of IEC-6 cells against hydrogen peroxide or indomethacin was studied by MTT assay, LDH-release assay, caspase-8 activity, and TUNEL. HSP60 was significantly induced by TJ-43. Cell necrosis and apoptosis were significantly suppressed in IEC-6 cells pretreated by TJ-43 with overexpression of HSP60. Our results suggested that HSP60 induced by TJ-43 might play an important role in protecting small intestinal epithelial cells from apoptosis and necrosis in vitro.
Evidence-based Complementary and Alternative Medicine 01/2012; 2012:278958. · 4.77 Impact Factor
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Kouji Tanimoto,
Kurumi Suzuki,
Eija Jokitalo,
Noriko Sakai,
Tomoaki Sakaguchi,
Daisuke Tamura,
Gourou Fujii,
Kenji Aoki,
Saya Takada,
Ryuichi Ishida,
Masako Tanabe, Hideaki Itoh,
Yukio Yoneda,
Miwa Sohda,
Yoshio Misumi,
Nobuhiro Nakamura
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ABSTRACT: The Yip1 domain family (YIPF) proteins are homologues of yeast Yip1p and Yif1p, which are proposed to function in ER to Golgi transport. Here, we report the characterization of YIPF3 and YIPF4, homologues of human Yif1p and Yip1p, respectively. Immunofluorescence and immuno-electron microscopy showed that both YIPF3 and YIPF4 are clearly concentrated in the cis-Golgi. While YIPF4 was detected as a single mobility form consistent with its predicted molecular weight, three different mobility forms of YIPF3 were detected by western blotting. Biochemical and immunofluorescence experiments strongly indicated that YIPF3 is synthesized in the ER as a N-glycosylated form (40 kDa), is then O-glycosylated in the Golgi apparatus to become a lower mobility form (46 kDa) and finally becomes a higher mobility form cleaved at its C-terminal luminal domain (36 kDa). YIPF3 and YIPF4 form a complex in the Golgi apparatus, and this was suggested to be important for their proper localization and function. The knockdown of YIPF3 or YIPF4 in HeLa cells induced fragmentation of the Golgi apparatus, suggesting their involvement in the maintenance of the Golgi structure.
Cell Structure and Function 07/2011; 36(2):171-85. · 2.29 Impact Factor
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ABSTRACT: In the clinical field, increasing incidence of small intestinal ulcers associated with nonsteroidal anti-inflammatory drugs (NSAIDs) has become a topic with the advances of capsule endoscopy and balloon enteroscopy technology for the detection of small intestinal lesions. However, the pathogenesis of NSAID-induced mucosal damage, defensive mechanism of intestinal epithelial cells, and therapy for small intestinal mucosal lesion have not been fully understood. Heat shock proteins (HSPs) are involved in cytoprotection mediated by their function as a molecular chaperone. Since the function of HSP90 in the intestinal epithelial cells has not been well investigated, we examined the cytoprotective ability of HSP90-overexpressing small intestinal epithelial cells against hydrogen peroxide-induced or indomethacin-induced cell damage.
cDNA of human HSP90 gene was transfected to rat small intestinal epithelial cells (IEC-6 cells), and HSP90-overexpressing cells (IEC-6-90 cells) were selected and cloned. Anti-necrotic abilities and anti-apoptotic abilities of IEC-6-90 cells were compared with IEC-6-mock cells (transfected with vector alone). To examine the specific contribution of HSP90 on cytoprotection of IEC-6-90 cells, cytoprotective ability of IEC-6-90 cells was analyzed with or without pretreatment with functional inhibitor of HSP90, geldanamycine analog, followed by hydrogen peroxide-challenge or indomethacin-challenge.
Hydrogen peroxide-induced or indomethacin-induced cell necrosis and apoptosis were significantly suppressed in IEC-6-90 cells. The cytoprotective ability of IEC-6-90 cells was suppressed by HSP90 inhibitor.
Our results suggest that HSP90 might play an important role in protecting small intestinal epithelial cells from hydrogen peroxide-induced or indomethacin-induced cell injury in vitro, and raised the possibility of protection of small intestinal epithelial cells by manipulation of HSP90 expression.
Digestive Diseases and Sciences 01/2011; 56(7):1954-61. · 2.12 Impact Factor
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Hiroshi Kubota,
Soh Yamamoto,
Eri Itoh,
Yuki Abe,
Asami Nakamura,
Yukina Izumi,
Hirotaka Okada,
Masatake Iida,
Hiroshi Nanjo, Hideaki Itoh,
Yuzo Yamamoto
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ABSTRACT: Co-chaperone HOP (also called stress-inducible protein 1) is a co-chaperone that interacts with the cytosolic 70-kDa heat shock protein (HSP70) and 90-kDa heat shock protein (HSP90) families using different tetratricopeptide repeat domains. HOP plays crucial roles in the productive folding of substrate proteins by controlling the chaperone activities of HSP70 and HSP90. Here, we examined the levels of HOP, HSC70 (cognate of HSP70, also called HSP73), and HSP90 in the tumor tissues from colon cancer patients, in comparison with the non-tumor tissues from the same patients. Expression level of HOP was significantly increased in the tumor tissues (68% of patients, n = 19). Levels of HSC70 and HSP90 were also increased in the tumor tissues (95% and 74% of patients, respectively), and the HOP level was highly correlated with those of HSP90 (r = 0.77, p < 0.001) and HSC70 (r = 0.68, p < 0.01). Immunoprecipitation experiments indicated that HOP complexes with HSC70 or HSP90 in the tumor tissues. These data are consistent with increased formation of co-chaperone complexes in colon tumor specimens compared to adjacent normal tissue and could reflect a role for HOP in this process.
Cell Stress and Chaperones 11/2010; 15(6):1003-11. · 3.01 Impact Factor
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ABSTRACT: Recent studies have indicated that heat shock proteins (HSPs), which function as molecular chaperones, play important roles in cellular responses to stress-related events. However, the gender difference in the expression of HSP in the gastric mucosa remains unclear. In order to understand the mechanism of gender difference in the prevalence or severity of gastric mucosal lesions, the expression level of HSP and the correlation of estrogen to HSP induction in the gastric mucosa were evaluated in this study. The basal expression levels of HSP60 and HSP90 in the gastric mucosa were significantly higher in females than those in males. The gastric ulcer index was significantly higher in male rats compared to female rats observed after 12 h water immersion stress exposure. At this time point, the expression levels of HSP60 and HSP90 in the gastric mucosa were significantly higher in females than those in males. An estrogen-treatment significantly induced the expression of HSP60, HSP70 and HSP90 in the gastric mucosa. Inversely, an ovariectomy dramatically reduced the expression of HSP60, HSP70 and HSP90 in the gastric mucosa. Our results suggested that estrogen might play an important role in gastric mucosal protection with the induction of gastric mucosal HSPs.
Journal of Clinical Biochemistry and Nutrition 07/2010; 47(1):64-73. · 1.98 Impact Factor
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Makiko Takada,
Michiro Otaka,
Taiji Takahashi,
Yuko Izumi,
Kumiko Tamaki,
Tomoyoshi Shibuya,
Naoto Sakamoto,
Taro Osada,
Sou Yamamoto,
Ryuichi Ishida,
Masaru Odashima, Hideaki Itoh,
Sumio Watanabe
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ABSTRACT: With the advancement of small intestinal (double balloon and capsule) endoscopy technology, incidence of small intestinal lesion caused by nonsteroidal anti-inflammatory drugs (NSAIDs) has been known to be high. However, therapy for small intestinal mucosal lesion has not yet been developed. Previous studies have shown that heat shock proteins (HSPs) are involved in cytoprotection mediated by their function as a molecular chaperone. In this study, we examined the effect of HSP60 or HSP70 overexpression on hydrogen peroxide-induced (H2O2) or indomethacin-induced cell damage in the small intestinal epithelial cells.
cDNA of human HSP60 or HSP70 was transfected to rat small intestinal (IEC-6) cells, and HSP60- or HSP70-overexpressing cells were cloned. IEC-6 cells transfected with vector only were used as control cells. These cells were treated with H2O2 (0-0.14mM) or indomethacin (0-2.5mM). The cell viability was determined by MTT-assay. Cell necrosis was evaluated by LDH-release assay. Further, apoptosis was evaluated by caspases-3/7 activity and TUNEL assay.
Cell viability after H2O2 or indomethacin treatment was significantly higher in HSP60-overexpressing cells compared with that in control cells and HSP60-overexpressing cells. Apoptotic cells were also reduced in HSP60-overexpressing. Conclusion: These results indicate that HSP60 plays an important role in protecting small intestinal mucosal cells from H2O2-induced or indomethacin-induced cell injury. HSP70-overexpressing cells did not show anti-apoptotic ability.
These findings possibly suggest that function of each HSP is different in the small intestine. Therefore, for the therapy of small intestinal mucosal lesion, HSP60-induction therapy could be a new therapeutic strategy.
Life sciences 02/2010; 86(13-14):499-504. · 2.56 Impact Factor
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Soh Yamamoto,
Shunsuke Nakano,
Kensuke Owari,
Kazuhiko Fuziwara,
Nobuaki Ogawa,
Michiro Otaka,
Kumiko Tamaki,
Sumio Watanabe,
Atsushi Komatsuda,
Hideki Wakui,
Ken-Ichi Sawada,
Hiroshi Kubota, Hideaki Itoh
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ABSTRACT: We previously reported that gentamicin (GM) specifically binds to heat-shock protein with subunit molecular masses of 70 kDa (HSP70). In the present study, we have investigated the effects of GM binding on HSP70-assisted protein folding in vitro. The C-terminal, and not the N-terminal of HSP70 was found to bind to GM. GM significantly suppressed refolding of firefly luciferase in the presence of HSP70 and HSP40, although the ATPase activity of HSP70 was unaffected by GM. A surface plasmon resonance analysis revealed that GM specifically interferes with the binding of HSP70 to a model peptide that mimics the exposed hydrophobic surface of the folding intermediates. These results indicated that GM inhibits the chaperone activity of HSP70 and may suppress protein folding via inhibition of HSP70 in vivo.
FEBS letters 12/2009; 584(4):645-51. · 3.54 Impact Factor
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Journal of Polymer Science Part A Polymer Chemistry 09/2009; 47(21):5835 - 5844. · 3.92 Impact Factor
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ABSTRACT: The aim of this study is to investigate the expression and cytoprotective function of a 72-kDa heat shock protein (HSP72) using a reflux esophagitis model in rats.
Expression of HSP60, HSP72, and HSP90 in rat esophageal mucosa was evaluated by Western blot analysis before and after hyperthermia (42.5 degrees C, 20 min). Rats received the operation to produce reflux esophagitis with or without pretreatment with hyperthermia to induce HSPs. The esophageal mucosal damage was evaluated 12 h after the operation.
Expression of HSP72 was significantly increased by hyperthermia in rat esophageal mucosa. Reflux esophagitis was dramatically prevented when HSP72 was preinduced by hyperthermia. Furthermore, activation of TNF-alpha and IL-1beta in esophageal mucosa was also suppressed.
These results suggested that hyperthermia protects the esophageal mucosa in reflux esophagitis model by inducing HSP72 and suppressing proinflammatory cytokine activation. These findings might suggest that HSP-inducing therapy could be a novel and unique therapy for reflux esophagitis.
Life sciences 05/2009; 84(15-16):517-22. · 2.56 Impact Factor
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Michiro Otaka,
Masaru Odashima,
Yuko Izumi,
Akihito Nagahara,
Taro Osada,
Naoto Sakamoto,
Makiko Takada,
Taiji Takahashi,
Yuji Shimada,
Kumiko Tamaki,
Daisuke Asaoka, Hideaki Itoh,
Sumio Watanabe
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ABSTRACT: Several recent studies, including ours, have indicated the importance of heat shock proteins (HSPs) in cytoprotection against cytotoxic agents and environmental stresses mediated by the chaperone function of HSPs (molecular chaperones). However, the target molecule that is recognized by HSPs in damaged cells currently remains unknown. As HSPs rapidly recognize and bind to degenerated protein in cells, target molecules of HSPs might be key molecules for the initiation and pathogenesis of cellular damage. In the present study, gastric mucosal proteins that specifically bind to the HSP70 family (HSC70) were analyzed using HSC70-affinity chromatography.
The gastric mucosa was removed from Sprague-Dawley rats after exposure to water immersion-stress for 0, 1, 3 or 5 h. Soluble fractions of each gastric mucosa were applied to the HSC70-affinity column separately. After washing off non-specific binding proteins, specific binding proteins were eluted by ATP-containing buffer. Binding proteins were analyzed by SDS-polyacrylamide gel electrophoresis. In addition, the amino acid sequence of purified proteins was also analyzed.
Specific HSC70-binding proteins with a molecular weight of 200-kDa and 45-kDa were eluted from an affinity column when gastric mucosal homogenate of 1-h stress exposure was applied. The amino acid sequencing showed that these binding proteins were cytoskeletal myosin (heavy chain) and actin, respectively.
During the pathogenesis of stress-induced gastric mucosal damage, structurally degenerated cytoskeletal myosin (heavy chain) and actin may be key or initiation molecules which structural changes were firstly recognized by molecular chaperone.
Life sciences 04/2009; 84(19-20):664-7. · 2.56 Impact Factor
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Ryuichi Ishida,
Yuka Takaoka,
Soh Yamamoto,
Toshio Miyazaki,
Michiro Otaka,
Sumio Watanabe,
Atushi Komatsuda,
Hideki Wakui,
Ken-Ichi Sawada,
Hiroshi Kubota, Hideaki Itoh
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ABSTRACT: The 90-kDa heat shock protein (HSP90) is a molecular chaperone that assists in the folding and assembly of proteins in the cytosol. We previously demonstrated that the antineoplastic reagent, cisplatin, inhibits the aggregation prevention activity of mammalian HSP90. We now show that cisplatin binds both the amino terminal and carboxyl terminal domains of the human HSP90 and differently affects these two domains. Cisplatin blocks the aggregation prevention activity of HSP90C, but not HSP90N. In contrast, cisplatin induces a conformational change in HSP90N, but not HSP90C. These results indicate that cisplatin modulates the HSP90 activities through two different mechanisms using the two distinct binding sites of the HSP90 molecule.
FEBS Letters 12/2008; 582(28):3879-83. · 3.54 Impact Factor
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ABSTRACT: The major heat shock protein, HSP70, is known to be involved in cytoprotection against environmental stresses mediated by their function as a "molecular chaperone." However, the influence of HSP70 on gastric mucosal healing under physical stimulation or stress is not completely understood. Rat gastric mucosal cells (RGM-1) were stably transfected with pBK-CMV containing the human HSP70 gene (7018-RGM-1) or pBK-CMV alone (pBK-CMV-12). Artificial wounds were created. Mechanical stretch was applied to 7018-RGM-1 cells or pBK-CMV-12 cells. The effect of mechanical stretch on HSP70 expression was assessed by Western blot analysis. Expression of HSP70 was decreased by mechanical stretch in pBK-CMV-12 cells. However, expression of HSP70 was not decreased by mechanical stretch in 7018-RGM-1 cells. Furthermore, the wound restoration of pBK-CMV-12 cells was suppressed under mechanical stretch condition. On the other hand, the wound restoration of 7018-RGM-1 cells was not affected by mechanical stretch. These results suggest that HSP70 plays an important role in gastric wound healing under physical stress.
Digestive Diseases and Sciences 12/2007; 52(11):3087-91. · 2.12 Impact Factor
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ABSTRACT: Recent in vitro studies have suggested a chaperone function of 73 kDa heat-shock protein (HSP73) in targeting denatured proteins to lysosomes for degradation. We previously reported the induction of HSP73 in rat kidneys with gentamicin-induced acute tubular injury, and suggested that HSP73 might accumulate in injured lysosomes by observations at light microscopic level. In this study, we examined serial intracellular localizations of HSP73 in this animal model at electron microscopic level. Sprague-Dawley rats received gentamicin (80 mg/kg per day) for 14 days, and developed acute proximal tubular injury. After the gentamicin exposure, HSP73 moved from the nucleus to the cytoplasm, and was expressed within enlarged lysosomes in the injured proximal tubular epithelial cells. These accumulations started to appear from 36 h after the first gentamicin exposure, enlarged in size until day 12, and gradually diminished after day 18. At day 27, the HSP73 localization pattern returned to that of the normal kidney. We next observed serial intracellular localizations of a renal isoform of argininosuccinate synthetase (ASS), which is not a chaperone protein. Argininosuccinate synthetase was mainly expressed in the cytoplasm of normal proximal tubular epithelial cells. After the gentamicin exposure, ASS also accumulated within the lysosomes, but the magnitude of this lysosomal accumulation was less than that of HSP73. These findings in vivo support the suggested function of HSP73 in lysosomal protein degradation pathways. HSP73 may have a role in the disposition of damaged proteins for the repair of target cells from gentamicin nephrotoxicity.
Nephrology 04/2007; 3(6):413 - 419. · 1.31 Impact Factor
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ABSTRACT: We previously reported the induction of 90 kDa heat-shock protein (HSP90) in rat kidneys with cisplatin-induced acute tubular injury, gentamicin-induced acute renal failure and ischaemia-induced acuterenal failure. In the present study, we examined the expression of HSP90 in normal and diseased human kidneys. the 90-kDa heat-shock protein (HSP90) from mouse brains was purified, and a specific antibody against the protein in a rabbit was produced. This antibody cross-reacted with human renal HSP90 on immunoblot analysis. Using this antibody we observed the intrarenal immunohistochemical localization of HSP90 in both normal and various human diseased kidneys. We also examined the differences between the distributions of macrophages and HSP90 in cellular crescents. In the normal kidney, HSP90 was present in glomerular podocytes, Bowman's epithelia and epithelial cells from the distal tubules to the collecting duct. In diseased kidneys HSP90 was markedly expressed in the cytoplasm of proliferative cells within cellular crescents, but not in fibrocellular crescents. the localization of HSP90 in crescents did not coincide with that of macrophages. These results demonstrated that HSP90 is induced in the cytoplasm of cellular crescents. Heat-shock protein 90 may be expressed partly in response to some factors produced by macrophages.
Nephrology 04/2007; 2(2):87 - 91. · 1.31 Impact Factor
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ABSTRACT: Indole beta-cyclodextrin (beta-1) was found to be able to prevent aggregation of citrate synthase (CS) on heating condition. As a result, beta-1 showed anti-CS aggregation in this system by regulating in early stage. The depression mechanism of beta-1 for aggregation of CS is as follows: the beta-1 formed a complex with hydrophobic parts of the beta-sheet structure of CS. From CD spectra, CS was changed own conformation was changed by beta-1 addition. So, it was concluded that beta-1 works as beta-sheet inducer in thermal condition. On the other hand, native beta-cyclodextrin (beta-CyD) shows small suppression capability for CS aggregation.
Bioorganic & Medicinal Chemistry 04/2007; 15(5):1983-8. · 2.92 Impact Factor
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Michiro Otaka,
Soh Yamamoto,
Kaori Ogasawara,
Yuka Takaoka,
Susumu Noguchi,
Toshio Miyazaki,
Akira Nakai,
Masaru Odashima,
Tamotsu Matsuhashi,
Sumio Watanabe, Hideaki Itoh
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ABSTRACT: To elucidate the induction mechanism of HSP70 by geranylgeranylacetone (GGA), we investigated GGA specific binding proteins using a GGA-affinity column. Alteration of chaperone activity of HSP70 and binding affinity of HSP70 to heat shock factor-1 (HSF-1) was evaluated in the presence or absence of GGA. The binding domain of HSP70 to GGA was also analyzed. A 70-kDa protein eluted by 10 mM GGA from the GGA-affinity column was identical to constitutively expressed HSP70 on immunoblotting. GGA-binding domain of HSP70 was C-terminal of the protein as peptide-binding domain (HSP70C). The chaperone activity of HSP70 and recombinant HSP70C was suppressed by GGA. Furthermore, dissociation of the HSP70 from HSF-1 was observed in the presence of GGA. GGA preferentially binds to the C-terminal of HSP70 which binds to HSF-1. After dissociation of HSP70, free HSF-1 could acquire the ability to bind to HSE (the promoter region of HSP70) gene.
Biochemical and Biophysical Research Communications 03/2007; 353(2):399-404. · 2.48 Impact Factor
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ABSTRACT: Antibody binding to bovine serum albumin (BSA) and human serum albumin (HSA) immobilized onto gold nanoparticles was studied by means of localized surface plasmon resonance (LSPR) spectroscopy. Amine-modified glass was prepared by self-assembly of amine-terminated silane on substrate, and gold (Au) nanoparticles were deposited on the amine-modified glass substrate. Au nanoparticles deposited on the glass surface were functionalized by BSA and HSA. BSA immobilization was confirmed by LSPR spectroscopy in conjunction with surface-enhanced Raman scattering spectroscopy. Then, LSPR response attributable to the binding of anti-BSA and anti-HSA to BSA- and HSA-functionalized Au nanoparticles, respectively, was examined. Anti-HSA at levels larger than approximately 10 nM could be detected by HSA-immobilized chips with LSPR optical response, which was saturated at concentrations greater than approximately 650 nM of anti-HSA.
Analytical and Bioanalytical Chemistry 11/2006; 386(3):639-44. · 3.78 Impact Factor
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Isao Wada,
Michiro Otaka,
Mario Jin,
Masaru Odashima,
Koga Komatsu,
Noriaki Konishi,
Tamotsu Matsuhashi,
Youhei Horikawa,
Reina Ohba, Hideaki Itoh,
Sumio Watanabe
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ABSTRACT: The real mechanism of adaptive cytoprotection in the gastric mucosa is not well established. In the present study, we investigated the effect of acid suppressing agents on a 72-kDa heat shock protein (HSP72) expression, which is known as endogenous cytoprotective factor, in the gastric mucosa. Also, the association of gastric mucosal protective function against HCl-challenge was compared between HSP72-induced and -reduced group.
Expression of HSP72 was measured by Western blotting in the gastric mucosa before and after administration of famotidine or omeprazole. The gastric mucosal protective function against 0.6 N HCl was compared between control group and HSP72-reduced group. Also, the effect of increased expression of gastric HSP72 by additional administration of zinc sulfate or zinc L-carnosine, which is known as HSP72-inducer, on mucosal protective function was studied.
HSP72 expression in the gastric mucosa was reduced by acid suppressing agents. The lowest expression level of HSP72 was observed 12 h (famotidine, H2-receptor antagonist) or 48 h (omeprazole, proton pump inhibitor) after administration. The gastric mucosal protective ability against 0.6 N HCl was also reduced when HSP72 expression was decreased by famotidine or omeprazole. This phenomenon was reversed by HSP72 induction by additional administration of zinc derivatives.
Our results might indicate that the expression of HSP72 in the gastric mucosa is physiologically regulated by gastric acid, and that HSP72 induction could be important in view of mucosal protection especially when HSP72 expression is reduced by administration of acid suppressing agents such as proton pump inhibitor or H2 receptor antagonist.
Biochemical and Biophysical Research Communications 11/2006; 349(2):611-8. · 2.48 Impact Factor
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Jinko Oyake,
Michiro Otaka,
Tamotsu Matsuhashi,
Mario Jin,
Masaru Odashima,
Koga Komatsu,
Isao Wada,
Youhei Horikawa,
Reina Ohba,
Natsumi Hatakeyama, Hideaki Itoh,
Sumio Watanabe
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ABSTRACT: The major heat shock protein, HSP70, is known to be involved in cytoprotection against environmental stresses mediated by their function as a "molecular chaperone". Monochloramine (NH(2)Cl) is a potent cytotoxic oxidant generated by neutrophil-derived hypochlorous acid and Helicobacter pylori urease-induced ammonia. In this study, to evaluate the cytoprotective effect of HSP70 against NH(2)Cl-induced gastric mucosal cell injury, rat gastric mucosal cells (RGM-1) were stably transfected with pBK-CMV containing the human HSP70 gene (7018-RGM-1) or pBK-CMV alone (pBK-CMV-12) as control cells. These cells were treated with various concentrations of NH(2)Cl. Cell Viability was determined by MTT assay and the direct plasma membrane damage was analyzed by lactate dehydrogenase (LDH) release assay. Apoptosis was determined by DNA fragmentation analysis. NH(2)Cl caused injury to pBK-CMV-12 cells in a concentration-dependent manner. NH(2)Cl-induced gastric cell injury was significantly diminished in HSP70 over-expressing cell line (7018-RGM-1) both necrosis and apoptosis compared to the control cell line (pBK-CMV-12) transfected with CMV vector alone. These result suggest that overexpression of HSP70 plays an important role in protecting gastric cells against NH(2)Cl-induced injury.
Life Sciences 07/2006; 79(3):300-5. · 2.53 Impact Factor
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ABSTRACT: Pleurocybella porrigens related encephalopathy exhibits consciousness disturbance and convulsion in the patients after taking and patients show bilateral basal ganglia lesion resulted in high mortality rate. This encephalopathy is a very similar to the moldy sugarcane encephalopathy epidemic in China in the past. We investigated the relationship between Pleurocybella porrigens related encephalopathy and 3-nitropropionic acid which had caused the moldy sugarcane encephalopathy. We have tried to detect 3-NPA in the various specimens from patients and Pleurocybella porrigens, but failed. Further examinations for elucidating the causation of Pleurocybella porrigens related encephalopathy are needed.
Nō to shinkei = Brain and nerve 05/2006; 58(4):311-7.
