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Kim W, Lee H, Kim S, Joo S, Jeong S, Yoo JW, Jung Y. Sofalcone, a gastroprotective drug, covalently binds to KEAP1 to activate Nrf2 resulting in anti-colitic activity. Eur J Pharmacol 2019; 865:172722. [PMID: 31614142 DOI: 10.1016/j.ejphar.2019.172722] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/26/2019] [Accepted: 10/02/2019] [Indexed: 12/23/2022]
Abstract
Sofalcone is a synthetic chalcone being used as a gastric mucosa protective agent in Japan. Sofalcone contains a 1,3-diaryl-2-propen-1-one moiety, which is a common chemical scaffold in naturally occurring chalcones. The α,β-unsaturated carbonyl group (Michael reaction acceptor) has electrophilic properties. We investigated the biochemical mechanisms by which sofalcone activated the cytoprotective and anti-inflammatory nuclear factor-erythroid 2 (NF-E2) p45-related factor 2 (Nrf2)-heme oxygenase (HO)-1 pathway. Furthermore, we investigated whether the activation of this pathway was involved in sofalcone -mediated protective effects in an experimental colitis model. Sofalcone induced HO-1 protein expression, which was dependent on increased nuclear accumulation of Nrf2 in human colon carcinoma cells. In addition, Sofalcone reacted with nucleophilic thiol compounds to form Michael adducts. A reduced form of sofalcone (SFCR) in which the Michael reaction acceptor was deactivated, did not exert biological or chemical activity. Biotin-tagged sofalcone bound to Kelch-like ECH-associated protein 1 (KEAP1), a cytosolic repressor of Nrf2. This binding was prevented by pretreatment with sofalcone and a thiol compound but not with SFCR. Furthermore, sofalcone treatment induced dissociation of the Nrf2-KEAP1 complex. Rectal administration of sofalcone alleviated colon damage and inflammation and increased colon nuclear accumulation of Nrf2 and HO-1 levels in a dinitrobenzene sulfonic acid-induced rat colitis model. The protective effects of sofalcone against colon damage and inflammation were significantly inhibited by co-administration of an HO-1 inhibitor. In conclusion, sofalcone activated the Nrf2-HO-1 pathway by covalently binding to KEAP1 via Michael addition, and may confer anti-colitic effects by inducing Nrf2 activation.
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Affiliation(s)
- Wooseong Kim
- College of Pharmacy, Pusan National University, Busan, Republic of Korea
| | - Hanju Lee
- College of Pharmacy, Pusan National University, Busan, Republic of Korea
| | - Soojin Kim
- College of Pharmacy, Pusan National University, Busan, Republic of Korea
| | - Sanghyun Joo
- College of Pharmacy, Pusan National University, Busan, Republic of Korea
| | - Seongkeun Jeong
- College of Pharmacy, Pusan National University, Busan, Republic of Korea
| | - Jin-Wook Yoo
- College of Pharmacy, Pusan National University, Busan, Republic of Korea
| | - Yunjin Jung
- College of Pharmacy, Pusan National University, Busan, Republic of Korea.
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The wound-healing effect of 7,3',4'-trimethoxyflavone through increased levels of prostaglandin E 2 by 15-hydroxyprostaglandin dehydrogenase inhibition. Biotechnol Lett 2017; 39:1575-1582. [PMID: 28664315 DOI: 10.1007/s10529-017-2386-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 06/22/2017] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To find an inhibitor of 15-hydroxyprostaglandin dehydrogenase (15-PGDH) that rapidly metabolises Prostaglandin E2 (PGE2) as a mediator of wound healing, we examined seven flavonoids for this role. RESULTS 7,3',4'-Trimethoxyflavone (TMF) had the lowest IC50 value of 0.34 µM for 15-PGDH inhibition but >400 µM for cytotoxicity, indicating a high therapeutic index. TMF elevated PGE2 levels in a concentration-dependent manner in both A549 lung cancer and HaCaT cells. It also significantly increased mRNA expression of multidrug resistance-associated protein 4 (MRP4) and of prostaglandin transporter (PGT) slightly in HaCaT cells. In addition, TMF facilitated in vitro wound healing in a HaCaT scratch model, which was completely inhibited by adding both 15-PGDH and NAD+ as cofactor, confirming the involvement of PGE2 in its wound healing effect. CONCLUSION TMF with a high therapeutic index can facilitate wound healing through PGE2 elevation by 15-PGDH inhibition.
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Tanaka H, Nakamura S, Onda K, Tazaki T, Hirano T. Sofalcone, an anti-ulcer chalcone derivative, suppresses inflammatory crosstalk between macrophages and adipocytes and adipocyte differentiation: Implication of heme-oxygenase-1 induction. Biochem Biophys Res Commun 2009; 381:566-71. [DOI: 10.1016/j.bbrc.2009.02.086] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 02/18/2009] [Indexed: 10/21/2022]
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Simultaneous Characterization of Sofalcone and Its Metabolite in Human Plasma by Liquid Chromatography -Tandem Mass Spectrometry. B KOREAN CHEM SOC 2005. [DOI: 10.5012/bkcs.2005.26.5.729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Isomoto H, Furusu H, Ohnita K, Wen CY, Inoue K, Kohno S. Sofalcone, a mucoprotective agent, increases the cure rate of Helicobacter pylori infection when combined with rabeprazole, amoxicillin and clarithromycin. World J Gastroenterol 2005; 11:1629-33. [PMID: 15786539 PMCID: PMC4305943 DOI: 10.3748/wjg.v11.i11.1629] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: The mucoprotective agents, sofalcone and polaprezinc have anti-Helicobacter pylori (H pylori) activities. We determined the therapeutic effects of sofalcone and polaprezinc when combined with rabeprazole, amoxicillin and clarithromycin for Helicobacter pylori infection.
METHODS: One hundred and sixty-five consecutive outpatients with peptic ulcer and H pylori infection were randomly assigned to one of the following three groups and medicated for 7 d. Group A: triple therapy with rabeprazole (10 mg twice daily), clarithromycin (200 mg twice daily) and amoxicillin (750 mg twice daily). Group B: sofalcone (100 mg thrice daily) plus the triple therapy. Group C: polaprezinc (150 mg twice daily) plus the triple therapy. Eradication was considered successful if 13C-urea breath test was negative at least 4 wk after cessation of eradication regimens or successive famotidine in the cases of active peptic ulcer.
RESULTS: On intention-to-treat basis, H pylori cure was achieved in 43 of 55 (78.2%) patients, 47 of 54 (87.0%) and 45 of 56 (80.4%) for the groups A, B and C respectively. Using per protocol analysis, the eradication rates were 81.1% (43/53), 94.0% (47/50) and 84.9% (45/53) respectively. There was a significant difference in the cure rates between group A and B. Adverse events occurred in 10, 12 and 11 patients, from groups A, B and C respectively, but the events were generally mild.
CONCLUSION: The addition of sofalcone, but not polaprezinc, significantly increased the cure rate of H pylori infection when combined with the rabeprazole-amoxicillin-clarithromycin regimen.
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Affiliation(s)
- Hajime Isomoto
- Second Department of Internal Medicine, Nagasaki University School of medicine, Nagasaki, Japan.
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Igarashi M, Takagi A, Jiang X, Hasumi K, Watanabe S, Deguchi R, Miwa T. Analysis of Helicobacter pylori and nonsteroidal anti-inflammatory drug-induced gastric epithelial injury. Aliment Pharmacol Ther 2002; 16 Suppl 2:235-9. [PMID: 11966547 DOI: 10.1046/j.1365-2036.16.s2.6.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Helicobacter pylori and nonsteroidal anti-inflammatory drugs (NSAIDs) are important factors in gastric mucosal injury. However, the relationship between H. pylori and NSAID-related gastroduodenal mucosal injury has not been clarified. AIM To determine the role of H. pylori in NSAID-induced gastric mucosal injury and to examine the effects of H. pylori, indomethacin and sofalcone on gastric epithelial cells in culture, as a useful model to study gastric mucosal injury. In addition, we studied the effect of sofalcone, a gastric mucosal protection agent, on H. pylori and NSAID-induced gastric mucosal injury. METHODS Cytotoxic and noncytotoxic strains of H. pylori were used, each with an inoculum of 10(7) cfu/mL. The effect on the growth of RGM-1 cells (a rat gastric epithelial cell line) was studied by MTT assay, and levels of prostaglandin E2 in culture supernatants were measured by EIA. RESULTS Both cytotoxic and noncytotoxic strains of H. pylori tended to induce cell injury in RGM-1 cells at 48 h after inoculation. Indomethacin alone induced gastric epithelial injury in a dose-dependent manner, but did not augment cell injury induced by H. pylori. In addition, sofalcone (10(-5) mol/L) showed a suppressive effect on indomethacin-induced gastric epithelial injury. CONCLUSION These findings indicate that indomethacin induces gastric mucosal injury regardless of H. pylori infection, and suggests that sofalcone may be a useful drug in the treatment of NSAID-induced mucosal injury.
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Affiliation(s)
- M Igarashi
- Division of Gastroenterology, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Kanagawa, Japan
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Yoshiyama H, Nakamura H, Okamoto T, Okita K, Nakazawa T. A novel in vitro effect of the mucosal protective agent sofalcone--inhibition of chemotactic motility in Helicobacter pylori. Aliment Pharmacol Ther 2000; 14 Suppl 1:230-6. [PMID: 10807429 DOI: 10.1046/j.1365-2036.2000.014s1230.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Motility of Helicobacter pylori is essential for colonization. H. pylori has been shown to exhibit chemotactic activity toward urea and sodium and bicarbonate ions, which are secreted from the gastric epithelia. The importance of urease activity for chemotactic motility of H. pylori in a viscous environment has also been shown. Consequently, application of drugs inhibiting chemotactic motility has been proposed as a strategy for H. pylori eradication. This inhibitory effect can be evaluated through assay of chemotaxis and swarming. MATERIALS AND METHODS H. pylori CPY3401 and ATCC43504 were grown on brucella agar plates/broth supplemented with 3% horse serum under microaerobic conditions (N2, 85%; O2, 5%; CO2, 10%). For motility assay, H. pylori cells grown on brucella-serum agar were stabbed into motility agar containing 0.35% refined agar in brucella-serum broth and the swarming zone was measured. For the chemotaxis assay, cells were suspended in 10 mM potassium phosphate buffer, pH 7.0, with 3% polyvinyl-pyrrolidone and assayed as described previously. Bacterial swimming in the fluid environment was observed under dark-field microscopy. RESULTS Numbers of bacteria attracted toward 1 microM flurofamide were reduced with increasing concentrations of sofalcone (0.2-222 microM). In addition, the size of the swarming zone was reduced in motility agar containing 22 and 222 microM sofalcone. On the other hand, 22 microM sofalcone did not inhibit bacterial growth on day 3. Bacterial swimming speed in brucella broth was slower in the presence of 22 and 222 microM sofalcone than in its absence. CONCLUSION Sofalcone was found to inhibit chemotactic motility of H. pylori. This drug may be useful for inhibiting the bacterium's ability to colonize the human stomach.
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Affiliation(s)
- H Yoshiyama
- Department of Microbiology, Yamaguchi University School of Medicine, Ube, Japan
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Kabir AM, Shimizu K, Aiba Y, Igarashi M, Takagi A, Koga Y. The effect of sofalcone on indomethacin-induced gastric ulcers in a Helicobacter pylori-infected gnotobiotic murine model. Aliment Pharmacol Ther 2000; 14 Suppl 1:223-9. [PMID: 10807428 DOI: 10.1046/j.1365-2036.2000.014s1223.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Abstract
BACKGROUND Sofalcone has been reported to exert anti-ulcer and gastroprotective actions, but its exact mechanism of action remains unknown. In our laboratory, we found that indomethacin-induced gastric ulcers become worse when associated with Helicobacter pylori infection. METHODS We employed the H. pylori-infected gnotobiotic murine model to examine the effect of sofalcone on indomethacin-induced gastric ulcers in the presence of H. pylori infection. In vitro experiments were also done to evaluate the effects of sofalcone on H. pylori growth, adherence of H. pylori to the MKN45 cells (a human gastric epithelial cell line), and these cells' IL-8 production in the presence of H. pylori. RESULTS We found that sofalcone produced a significant improvement in ulcer size as well as a substantial reduction in the number of H. pylori colonies in H. pylori-infected gnotobiotic mice. In vitro sofalcone has a significant bacteriocidal effect against H. pylori and can also significantly prevent adherence of this bacterium to MKN45 cells, thus remarkably reducing IL-8 production of these cells in response to stimulation by H. pylori. CONCLUSION Our results suggest that sofalcone can improve ulcer healing by the mechanisms mentioned above.
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Affiliation(s)
- A M Kabir
- Department of Infectious Diseases, Tokai University School of Medicine, Isehara, Kanagawa, Japan
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Mochizuki S, Matsumoto M, Wakabayashi S, Kosakai K, Tomiyama A, Kishimoto S. Therapeutic effect of egualen sodium (KT1-32), a new antiulcer agent, on chronic gastritis induced by sodium taurocholate in rats. J Gastroenterol 1996; 31:785-92. [PMID: 9027640 DOI: 10.1007/bf02358603] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We investigated the therapeutic effects of egualen sodium (KT1-32), a new antiulcer agent, on chronic erosive and atrophic gastritis induced by 5 months' administration of sodium taurocholate (TCA; 5 mM) in rats. The chronic gastritis was manifested by mucosal surface injuries (erosions), reduced mucosal thickness, reduction of the number of parietal cells, infiltration of inflammatory cells, and proliferation of collagenous fiber. Egualen sodium, (10-100 mg/kg, t.i.d.) administered orally to the rats for 2 weeks after the withdrawal of TCA, dose-dependently and significantly decreased the total length of erosions. The indicators of atrophic gastritis, i.e., reduced mucosal thickness and reduction in the number of parietal cells, were improved dose-dependently by the administration of this agent. Egualen sodium also reduced the inflammatory cell infiltration and the proliferation of collagenous fiber in the gastric mucosa in a dose-dependent manner. The reduced staining of neutral gastric mucus was improved by a high dose (100 mg/kg) of egualen sodium. The therapeutic effects of egualen sodium on experimental gastritis were superior to those of sofalcone and sodium guaiazulene 3-sulfonate. These results suggest that egualen sodium may be a promising agent for the treatment of erosive and atrophic gastritis.
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Affiliation(s)
- S Mochizuki
- Research Laboratories, Kotobuki Pharmaceutical Co. Ltd., Nagano, Japan
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Hori Y, Odaguchi K, Jyoyama H, Yasui K, Mizui T. Differential effect of benexate hydrochloride betadex on prostaglandin levels in stomach and inflammatory site in rats. JAPANESE JOURNAL OF PHARMACOLOGY 1996; 72:183-90. [PMID: 8912919 DOI: 10.1254/jjp.72.183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We compared the effects of an anti-ulcer agent, benexate hydrochloride betadex (BHB), on prostaglandin (PG) levels in gastric tissue and inflammatory exudate in untreated and indomethacin-treated rats. BHB (100, 300 and 1000 mg/kg, p.o.) showed dose-dependent inhibition of gastric mucosal lesions induced by indomethacin (30 mg/kg, p.o.). Sustained decrease of PGs (PGE2 and 6-keto-PGF(1alpha)) in the gastric wall was observed from 0.5 to 6 hr after indomethacin treatment. BHB (300 and 1000 mg/kg) dose-dependently led to recovery of the indomethacin-induced decrease of gastric PGs at 1 and 6 hr after dosing. It did not antagonize the indomethacin-induced decrease of PG levels in the pleural exudate of carrageenin pleurisy nor did it affect the anti-inflammatory effects of indomethacin. BHB (100 to 1000 mg/kg) alone increased gastric PGE2 by 61% to 113%, while it decreased PGE2 levels in the pleural exudate by 9% to 71% at 6 hr after dosing. These results suggest that sustained increase of gastric PGE2 by BHB could be responsible for protection against indomethacin-induced gastric mucosal lesions and that BHB is a suitable anti-ulcer agent for NSAIDs without compromising their anti-inflammatory effects.
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Affiliation(s)
- Y Hori
- Division of Pharmacology, Discovery Research Laboratories II, Shionogi & Co., Ltd., Osaka, Japan
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Murakami S, Muramatsu M, Aihara H, Otomo S. Inhibition of gastric H+,K(+)-ATPase by the anti-ulcer agent, sofalcone. Biochem Pharmacol 1991; 42:1447-51. [PMID: 1656986 DOI: 10.1016/0006-2952(91)90458-h] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Effects of the anti-ulcer agent, sofalcone, on gastric H+,K(+)-ATPase were studied as well as those of other chalcone derivatives, chalcone and sophoradin. These drugs inhibited pig gastric H+,K(+)-ATPase in a dose-dependent manner. They were 5-10-fold less inhibitory toward Na+,K(+)-ATPase than H+,K(+)-ATPase. The potencies of these drugs on the inhibition of enzymes were as follows: sophoradin greater than sofalcone greater than chalcone. Kinetic studies showed that the inhibition of H+,K(+)-ATPase by sofalcone was competitive with respect to ATP and was non-competitive with respect to K+. Sofalcone also inhibited H+,K(+)-ATPase mediated proton transport and reduced the phosphoenzyme level. These results suggest that sofalcone inhibits gastric H+,K(+)-ATPase competitively with ATP at the ATP site and thereby blocks the phosphorylation of the enzyme. This may be the cause of the anti-secretory activity of sofalcone.
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Affiliation(s)
- S Murakami
- Research Center, Taisho Pharmaceutical Co. Ltd, Saitama, Japan
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12
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Fujimoto Y, Nakatani E, Minamino H, Takahashi M, Sakuma S, Fujita T. Effective use of rabbit gastric antral mucosal slices in prostaglandin synthesis and metabolism studies. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1044:65-9. [PMID: 2111174 DOI: 10.1016/0005-2760(90)90219-n] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Intact slice preparations of rabbit stomach (antral mucosa, corporal mucosa, antral muscle and corporal muscle) were incubated and the released prostaglandins (PGs) were measured by reverse-phase high-performance liquid chromatography using 9-anthryldiazomethane for derivatization. With respect to total PG production, the highest amounts were generated by antral mucosal slices. Antral mucosal slices produced PGE2, 6-keto PGF1 alpha, thromboxane B2, PGF2 alpha and PGD2 (in descending order of magnitude) and possessed a high capacity for producing 13,14-dihydro-15-keto derivatives of both PGE2 and PGF2 alpha. Studies utilizing aspirin, EGTA or Ca2+ revealed that PG release by antral mucosal slices in the present in vitro system reflects a composite of the activities of phospholipase A3, PG cyclooxygenase and PG-metabolizing enzymes. These results show that antral mucosal slices will be useful in physiological and pharmacological studies on PG synthesis and metabolism of the stomach.
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Affiliation(s)
- Y Fujimoto
- Department of Hygienic Chemistry, Osaka University of Pharmaceutical Sciences, Japan
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Oda T, Ushiyama S, Matsuda K, Iijima Y. Effect of an anti-ulcer drug, plaunotol, and its metabolites on NAD+ dependent 15-hydroxyprostaglandin dehydrogenase from gastric mucosa. Life Sci 1988; 43:1647-52. [PMID: 3193851 DOI: 10.1016/0024-3205(88)90537-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
15-Hydroxyprostaglandin dehydrogenase was partially purified from hog gastric mucosa by about 1000-fold with a 13.5% yield. Its molecular weight was estimated to be 32,000 daltons by gel filtration. The enzyme was inhibited by some metabolites of plaunotol [(2E, 6Z, 10E)-7-hydroxymethyl-3,11,15-trimethyl-2,6,10,14-hexadecatetrae n-1- ol], a new anti-ulcer drug. The inhibition patterns for substrates, prostaglandin E1 and NAD+ were both uncompetitive with Ki values of 7.8 and 19.7 microM, respectively.
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Affiliation(s)
- T Oda
- New Lead Research Laboratories, Sankyo Co., Ltd., Tokyo, Japan
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BILSKI J, SAROSIEK J, SLOMIANY A, SLOMIANY BL. Effect of Sofalcone on the Peptic Degradation of Gastric Mucus. Ann N Y Acad Sci 1987. [DOI: 10.1111/j.1749-6632.1987.tb45821.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Slomiany BL, Liau YH, Mizuta K, Slomiany A. Fatty acid acylation of mucin by gastric mucosa: effects of sofalcone and sucralfate. Biochem Pharmacol 1987; 36:3273-6. [PMID: 3663240 DOI: 10.1016/0006-2952(87)90644-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The effects of antiulcer drugs, sofalcone and sucralfate, on the activity of gastric mucosal mucus glycoprotein fatty acyltransferase were investigated. The acyltransferase enzyme, contained in the detergent extracts of the microsomal fraction of rat gastric mucosa, was incubated with the deacylated gastric mucin and palmitoyl-CoA substrates in the presence and absence of drugs, and the formed fatty acid acylated glycoprotein product was quantitated. In the absence of drugs, the enzymatic activity increased proportionally with increased concentrations of both substrates and of enzyme, and gave an apparent Km value of 5.6 X 10(-7) M. Introduction of sofalcone to the reaction mixtures led to an enhancement in the rate of mucus glycoprotein acylation. The rate of enhancement was proportional to sofalcone concentration up to 1.0 X 10(-5) M, with an apparent Km value of 3.7 X 10(-7) M. In contrast to sofalcone, the acyltransferase activity was inhibited by sucralfate. The rate of inhibition of mucus glycoprotein acylation by sucralfate was of the competitive type and at 1.0 X 10(-4) M reached a value of 25%. The apparent KI value calculated from the double-reciprocal plots for sucralfate was 9.1 X 10(-7) M. As the acylation of mucin with fatty acids plays an important role in the maintenance of gastric mucosal integrity, the results suggest that stimulation of the fatty acyltransferase enzyme by sofalcone may be one of the beneficial effects of this drug towards ulcer healing.
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Affiliation(s)
- B L Slomiany
- Department of Medicine, New York Medical College, Valhalla 10595
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Muramatsu M, Tanaka M, Murakami S, Aihara H. Inhibition of 15-hydroxy prostaglandin dehydrogenase and increase of prostaglandin E2: effect of sofalcone on rat gastric mucosa. Life Sci 1987; 41:315-22. [PMID: 3474485 DOI: 10.1016/0024-3205(87)90155-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The effect of sofalcone, an anti-ulcer agent, on gastric mucosal prostaglandin (PG) metabolism was studied. Gastric mucosal PGE2 was determined in rats in which PGE2 synthesis was inhibited by preadministration of indomethacin. Oral administration of sofalcone at doses of 200 and 400 mg/kg significantly inhibited the PG metabolizing enzyme, 15-hydroxy-PG-dehydrogenase (15-OH-PG-DH) activity and increased PGE2 contents in the rat gastric mucosa. The inhibition of 15-OH-PG-DH activity was accompanied by an increase of PGE2 contents up to 6 hours after the administration of sofalcone. These changes, however, were not observed 12 hours after its administration. Intraperitoneally administered sofalcone also inhibited 15-OH-PG-DH activity and increased PGE2 content. The inhibition of 15-OH-PG-DH activity by sofalcone was noncompetitive and uncompetitive against substrates NAD and PGE1, respectively. These results suggest that the increase of the gastric PGE2 level is mainly due to the inhibition of 15-OH-PG-DH activity, and this increase in PGE2 may be involved in the anti-ulcer effect of sofalcone.
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Ushiyama S, Matsuda K, Asai F, Yamazaki M. Stimulation of prostaglandin production by (2E,6Z,10E)-7-hydroxymethyl-3,11,15-trimethyl-2,6,10,14-++ +hexadecatetrae n-1-ol (plaunotol), a new anti-ulcer drug, in vitro and in vivo. Biochem Pharmacol 1987; 36:369-75. [PMID: 3101705 DOI: 10.1016/0006-2952(87)90296-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Plaunotol [(2E,6Z,10E)-7-hydroxymethyl-3,11,15-trimethyl-2,6,10,14- hexadecatetraen-1-ol], a new anti-ulcer drug, was investigated for its effect on prostaglandin (PG) production. In cultured cells of 3T6 fibroblasts, plaunotol and its main metabolite (1-carboxylic plaunotol) at concentrations of 10-100 microM increased PGE2 and PGI2 production 2- to 4-fold. These compounds increased the release of radioactive arachidonic acid from [14C]arachidonic acid prelabeled 3T6 fibroblast cells 2-fold at 30 microM, and this increase was inhibited by addition of mepacrine, a phospholipase inhibitor. Plaunotol and its main metabolite had no effect on PG cyclooxygenase activity. These results indicate that plaunotol and its main metabolite stimulate PG production by activating cellular phospholipase. In gastric-mucosa slices, PGE2 and PGI2 production was increased significantly either by oral administration of plaunotol to rats at a dose of 300 mg/kg or by addition of the main metabolite to the incubation medium. All these results suggest that plaunotol increases the PG levels in gastric mucosa by stimulating the PG biosynthesis, particularly the cellular phospholipase activity. The increased levels of PG may participate in the anti-ulcer activity of plaunotol.
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Garner A. Future opportunities for drug therapy in peptic ulcer disease. SCANDINAVIAN JOURNAL OF GASTROENTEROLOGY. SUPPLEMENT 1986; 125:203-10. [PMID: 2881345 DOI: 10.3109/00365528609093838] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Attempts to develop antisecretory agents showing a significant increase in potency and duration of action over currently available H2 antagonists have had to contend with the problem of gastric tumour induction during long-term toxicity testing in rats, and their clinical future is currently uncertain. A number of potential pharmacological approaches to ulcer therapy, unrelated to inhibition of acid secretion, can be identified upon which to base the search for new antiulcer drugs. Whether such agents are a commercially attractive proposition is debatable, given the disappointing early clinical experience with prostaglandins in acute healing studies together with the established efficacy and safety of cimetidine and ranitidine. Indeed it is difficult to foresee any agent challenging the dominance of H2 blockers during this century. By analogy with beta adrenoceptor antagonists, it is likely that new developments will take the form of some additions to the H2 range, improved formulations, additional indications, and possibly combination therapies with other drugs. Future research must address the different aetiologies of gastric and duodenal ulcer and other acid-peptic conditions as well as attempting to cure the disease rather than simply heal the ulcer. Advances in fields traditionally unrelated to peptic ulcer research such as growth regulation, vascular disorders, and inflammation may well provide the most profitable basis for longer-term drug research. Finally, animal toxicity studies with second generation antisecretory agents have inadvertently focused attention on gastric cancer, a disease where the need for new drugs is unquestionable.
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