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Geranylgeranylacetone induces heat shock protein-73 in rat small intestine
Geranylgeranylacetone Induces Heat Shock Protein-73 in Rat Small Intestine T. Tsuruma, A. Yagihashi, S. Koide, J. Araya, K. Tarumi, N. Watanabe, and K. Hirata
W
E PREVIOUSLY reported that the induction of heat shock protein (hsp) in rat small intestine by injection of sodium arsenite reduced the small intestinal ischemia-reperfusion injury.1 However, sodium arsenite would act as a toxic agent if more than a certain amount were injected. Therefore, we conducted a study to investigate a less toxic agent that could induce hsp in the small intestine. In this study, we used geranylgeranylacetone (GGA), known as an antiulcer agent (Teprenone).
MATERIALS AND METHODS Brawn-Norway rats weighing approximately 200 to 300 g were purchased from CLEA Japan Inc (Shizuoka, Japan). In each experiment, three rats were used. All animals were anesthetized with an intraperitoneal (IP) injection of 35 mg/kg body weight of sodium pentobarbital. To determine the suitable amount of GGA that could induce hsp in rat small intestine, the rats were divided into three experimental groups, all of which were administrated oral GGA: group 1 rats (50 mg/kg body weight; as emulsion with 5% gum arabic and 0.008% a-tocopherol), group 2 rats (100 mg/kg body weight), and group 3 rats (200 mg/kg body weight). To assess the induction of hsp in the small intestine, tissue samples were collected 8 hours after oral injection and processed by routine techniques before embedding in paraffin. Sections were stained with monoclonal antibody NT-22, which reacts with hsp-73.2 In addition, a blood sample was taken 8 hours after oral injection and the plasma concentration of teprenone was measured.
RESULTS
In group 1, at 8 hours after oral injection, the plasma concentration of teprenone was either at a very low level or not detectable and hsp-73 was not expressed. In groups 2 and 3, the plasma concentration of teprenone had increased and was strongly expressed. Figure 1 showed histologic finding expressed hsp-73 in group 3. Thus, oral administration of more than 100 mg/kg body weight GGA could induce hsp-73 in the small intestine of a rat.
Fig 1. Small intestine of Brown-Norway rat was stained with monoclonal antibody NT-22, which reacts with hsp-73, 8 hours after oral administration of geranylgeranylacetone.
acquire remarkably enhanced tolerance to subsequent nonthermal stress (eg, gastric cytoprotection against ethanolinduced damage,4 reduced organ damage in sepsis-induced lung injury5 and provide significant cardioprotection in isolated rat hearts subjected to ischemia-reperfusion injury.6 We previously reported that injection of sodium arsenite (6 mg/kg body weight, IP), could induce hsp-73 in the small intestine of a rat and its induction reduced the ischemiareperfusion injury in the small intestine by decreasing the plasma peak levels of inflammatory cytokines, such as tumor necrosis factor alpha and interleukin-8 (CINC), and tissue myeloperoxidase activity, as an indicator of the number of infiltrated neutrophils into the small intestine after ischemia-reperfusion.1 In this report, rats that received 6 mg/kg IP of sodium arsenite did not appear to be lethargic or anorectic. Thus, doses of less than or equal to 6 mg/kg IP revealed no signs of acute poisoning. However, sodium arsenite has toxic effects. Sodium arsenite is very
DISCUSSION
Hsp is induced by seemingly unrelated environmental stresses (such as caused by ethanol or sodium arsenite) and pathophysiological states (such as ischemia-reperfusion, inflammation, and oxidant injury3 other than thermal stress). There are reports that tissue-induced hsp can 0041-1345/99/$–see front matter PII S0041-1345(98)01559-0
From the Departments of Surgery and Laboratory Diagnosis, Sapporo Medical University School of Medicine, Sapporo, Japan. Address reprint requests to Dr Tsuruma, Department of Surgery, Sapporo Medical University School of Medicine, S-1, W16, Chuo-ku, Sapporo 060, Japan. © 1999 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010
572
Transplantation Proceedings, 31, 572–573 (1999)
GERANYLGERANYLACETONE
poisonous with an oral median lethal dose in rats of 41 mg/kg.7 Thus, a safer agent capable of inducing hsp is necessary if these treatments are to be performed clinically. Therefore, we investigated GGA, which is known as an antiulcer agent (Teprenone). The induction of hsp is mainly mediated by activation of pre-existing transcription factors. Recently, a family of heat shock factors has been identified,8 –11 and heat shock factor 1 has been identified as the mediator of stress-induced transcription of heat shock genes.11,12 Hirakawa et al suggest that the mechanism of hsp induction by GGA is that it may specifically induce transcriptional activation of heat shock genes.11 Our study showed that oral administration of GGA induced hsp-73 in the small intestine of a rat. In addition, we previously reported that the induction of hsp-73 reduced the rat’s small intestinal ischemia-reperfusion injury.1 Taken together with these reports, GGA may be a non-poisonous and beneficial agent capable of reducing ischemia-reperfusion injury in small intestine transplantation.
573
REFERENCES 1. Tsuruma T, Yagihashi A, Watanabe N, et al: Surgery (submitted) 2. Tsuboi N, Ishikawa M, Tamura Y, et al: Hybridoma 13:373, 1994 3. Welch WJ: Sci Am 268:56, 1993 4. Nakamura K, Rokutan K, Marui N, et al: Gastroenterology 101:161, 1991 5. Villar J, Ribiero SP, Mullen JBM, et al: Crit Care Med 22:914, 1994 6. Currie RW, Karmazyn M, Klco M, et al: Circ Res 63:543, 1988 7. Budavari S: The Merck Index, 11th ed. Rahway, NJ: Merck & Co; 1989, p 1356 8. Rabindran SKG, Giorgi G, Clos J, et al: Proc Natl Acad Sci USA 88:6906, 1991 9. Schuetz TJ, Gallo GJ, Sheldon L, et al: Proc Natl Acad Sci USA 88:6911, 1991 10. Nakai A, Morimoto RI: Mol Cell Biol 13:1983, 1993 11. Hirakawa T, Rokutan K, Nikawa T, et al: Gastroenterology 111:345, 1996 12. Baler R, Dahl G, Voellmy R: Mol Cell Biol 13:2486, 1993
W
E PREVIOUSLY reported that the induction of heat shock protein (hsp) in rat small intestine by injection of sodium arsenite reduced the small intestinal ischemia-reperfusion injury.1 However, sodium arsenite would act as a toxic agent if more than a certain amount were injected. Therefore, we conducted a study to investigate a less toxic agent that could induce hsp in the small intestine. In this study, we used geranylgeranylacetone (GGA), known as an antiulcer agent (Teprenone).
MATERIALS AND METHODS Brawn-Norway rats weighing approximately 200 to 300 g were purchased from CLEA Japan Inc (Shizuoka, Japan). In each experiment, three rats were used. All animals were anesthetized with an intraperitoneal (IP) injection of 35 mg/kg body weight of sodium pentobarbital. To determine the suitable amount of GGA that could induce hsp in rat small intestine, the rats were divided into three experimental groups, all of which were administrated oral GGA: group 1 rats (50 mg/kg body weight; as emulsion with 5% gum arabic and 0.008% a-tocopherol), group 2 rats (100 mg/kg body weight), and group 3 rats (200 mg/kg body weight). To assess the induction of hsp in the small intestine, tissue samples were collected 8 hours after oral injection and processed by routine techniques before embedding in paraffin. Sections were stained with monoclonal antibody NT-22, which reacts with hsp-73.2 In addition, a blood sample was taken 8 hours after oral injection and the plasma concentration of teprenone was measured.
RESULTS
In group 1, at 8 hours after oral injection, the plasma concentration of teprenone was either at a very low level or not detectable and hsp-73 was not expressed. In groups 2 and 3, the plasma concentration of teprenone had increased and was strongly expressed. Figure 1 showed histologic finding expressed hsp-73 in group 3. Thus, oral administration of more than 100 mg/kg body weight GGA could induce hsp-73 in the small intestine of a rat.
Fig 1. Small intestine of Brown-Norway rat was stained with monoclonal antibody NT-22, which reacts with hsp-73, 8 hours after oral administration of geranylgeranylacetone.
acquire remarkably enhanced tolerance to subsequent nonthermal stress (eg, gastric cytoprotection against ethanolinduced damage,4 reduced organ damage in sepsis-induced lung injury5 and provide significant cardioprotection in isolated rat hearts subjected to ischemia-reperfusion injury.6 We previously reported that injection of sodium arsenite (6 mg/kg body weight, IP), could induce hsp-73 in the small intestine of a rat and its induction reduced the ischemiareperfusion injury in the small intestine by decreasing the plasma peak levels of inflammatory cytokines, such as tumor necrosis factor alpha and interleukin-8 (CINC), and tissue myeloperoxidase activity, as an indicator of the number of infiltrated neutrophils into the small intestine after ischemia-reperfusion.1 In this report, rats that received 6 mg/kg IP of sodium arsenite did not appear to be lethargic or anorectic. Thus, doses of less than or equal to 6 mg/kg IP revealed no signs of acute poisoning. However, sodium arsenite has toxic effects. Sodium arsenite is very
DISCUSSION
Hsp is induced by seemingly unrelated environmental stresses (such as caused by ethanol or sodium arsenite) and pathophysiological states (such as ischemia-reperfusion, inflammation, and oxidant injury3 other than thermal stress). There are reports that tissue-induced hsp can 0041-1345/99/$–see front matter PII S0041-1345(98)01559-0
From the Departments of Surgery and Laboratory Diagnosis, Sapporo Medical University School of Medicine, Sapporo, Japan. Address reprint requests to Dr Tsuruma, Department of Surgery, Sapporo Medical University School of Medicine, S-1, W16, Chuo-ku, Sapporo 060, Japan. © 1999 by Elsevier Science Inc. 655 Avenue of the Americas, New York, NY 10010
572
Transplantation Proceedings, 31, 572–573 (1999)
GERANYLGERANYLACETONE
poisonous with an oral median lethal dose in rats of 41 mg/kg.7 Thus, a safer agent capable of inducing hsp is necessary if these treatments are to be performed clinically. Therefore, we investigated GGA, which is known as an antiulcer agent (Teprenone). The induction of hsp is mainly mediated by activation of pre-existing transcription factors. Recently, a family of heat shock factors has been identified,8 –11 and heat shock factor 1 has been identified as the mediator of stress-induced transcription of heat shock genes.11,12 Hirakawa et al suggest that the mechanism of hsp induction by GGA is that it may specifically induce transcriptional activation of heat shock genes.11 Our study showed that oral administration of GGA induced hsp-73 in the small intestine of a rat. In addition, we previously reported that the induction of hsp-73 reduced the rat’s small intestinal ischemia-reperfusion injury.1 Taken together with these reports, GGA may be a non-poisonous and beneficial agent capable of reducing ischemia-reperfusion injury in small intestine transplantation.
573
REFERENCES 1. Tsuruma T, Yagihashi A, Watanabe N, et al: Surgery (submitted) 2. Tsuboi N, Ishikawa M, Tamura Y, et al: Hybridoma 13:373, 1994 3. Welch WJ: Sci Am 268:56, 1993 4. Nakamura K, Rokutan K, Marui N, et al: Gastroenterology 101:161, 1991 5. Villar J, Ribiero SP, Mullen JBM, et al: Crit Care Med 22:914, 1994 6. Currie RW, Karmazyn M, Klco M, et al: Circ Res 63:543, 1988 7. Budavari S: The Merck Index, 11th ed. Rahway, NJ: Merck & Co; 1989, p 1356 8. Rabindran SKG, Giorgi G, Clos J, et al: Proc Natl Acad Sci USA 88:6906, 1991 9. Schuetz TJ, Gallo GJ, Sheldon L, et al: Proc Natl Acad Sci USA 88:6911, 1991 10. Nakai A, Morimoto RI: Mol Cell Biol 13:1983, 1993 11. Hirakawa T, Rokutan K, Nikawa T, et al: Gastroenterology 111:345, 1996 12. Baler R, Dahl G, Voellmy R: Mol Cell Biol 13:2486, 1993