Saudi Journal of Gastroenterology
Home About us Instructions Submission Subscribe Advertise Contact Login    Print this page  Email this page Small font sizeDefault font sizeIncrease font size 
Users Online: 39 


 
ARTICLES Table of Contents   
Year : 1998  |  Volume : 4  |  Issue : 2  |  Page : 90-95
Protective effect of amoxycillin on ethanol-induced gastric lesions in rats


Department of Medical Pharmacology, College of Medicine, King Saud University, Riyadh, Saudi Arabia

Click here for correspondence address and email

Date of Submission15-Oct-1997
Date of Acceptance25-Feb-1998
 

   Abstract 

Recent studies have suggested that amoxycillin may possess gastroprotective effects in addition to its known antimicrobial properties. Therefore, the present study was undertaken to investigate the potential gastric protective effects of amoxycillin and to determine its possible mechanism(s) of action in rats. Ethanol-induced gastric mucosal lesions in rats were used as an animal model. Nonprotein sulphydryl levels were measured spectrophotometrically. The antioxidant effect of amoxycillin was studied by luminol-dependent chemiluminescence technique in-vitro. Amoxycillin produced marked protection against ethanol-induced gastric lesions. The protective effect of amoxycillin was lost by prior treatment with a dose of indomethacin that is known to inhibit prostaglandin biosynthesis without induction of gastric ulcers. Furthermore, the concentration of nonprotein sulphydryls decreased significantly in gastric mucosa after administration of ethanol. Treatment with amoxycillin prevented this depletion. Additionally, amoxycillin dose-dependently inhibited the phorbol myristate acetate stimulated luminol dependent chemiluminescence responses of isolated human polymorphonuclear leukocytes in­vitro. These data indicate that the gastric protection effects of amoxycillin against ethanol­induced lesions may include generation of mucosal prostaglandins, prevention of nonprotein of sulphydryl depletion and antioxidant properties.

How to cite this article:
Al Swayeh OA. Protective effect of amoxycillin on ethanol-induced gastric lesions in rats. Saudi J Gastroenterol 1998;4:90-5

How to cite this URL:
Al Swayeh OA. Protective effect of amoxycillin on ethanol-induced gastric lesions in rats. Saudi J Gastroenterol [serial online] 1998 [cited 2020 Nov 24];4:90-5. Available from: https://www.saudijgastro.com/text.asp?1998/4/2/90/33896


Amoxycillin is a commonly used antimicrobial drug. Recent studies have implicated  Helicobacter pylori Scientific Name Search  pylori) in the pathogenesis of peptic ulcer diseases [1],[2],[3] . In 1987, Coghlan et al [4] reported that duodenal ulcer recurrence was dramatically reduced when H. pylori was eradicated. It has since been established that eradication of H. pylori prevents ulcer relapse, and this has been confirmed by many investigators [5],[6] . As H. pylori is a bacterial infection, a high rate of cure from any antimicrobial therapy should be expected. On the basis of this assumption, several studies in recent years, have reported the effectiveness of amoxycillin either alone [7] or in combination with other drugs in prevention of relapse of peptic ulcer diseases [8],[9],[10].

Recently, it has been suggested that amoxycillin might have other gastroprotective properties. Thus, it has been shown that amoxycillin afforded protection against gastric lesions induced by cysteamine [11] , reserpine [12] . Furthermore, Lam et al [13] , using an exvivo gastric chamber model in the rat, has reported that intragastric and intraperitoneal administration of amoxycillin dose-dependently protected the rat gastric mucosa from damage by ethanol. This protective effect of amoxycillin has been suggested to be mediated by prostaglandins since pretreatment with indomethacin was able to abolish this amoxycillin-induced gastric protection. However, the mechanism of action of amoxycillin has not been fully elucidated in this study. Therefore, the present study was undertaken in order to investigate the potential protective effect of amoxycillin and to determine its possible mechanisms of action against ethanol-induced gastric lesions in rats.


   Materials and Methods Top


Drugs and chemicals were obtained as indicated Amoxycillin injection (Beechams Pharmaceutical, UK) was purchased locally. Luminol, phorbol myristate acetate (PMA), 5-5 dithio-bis - (2­nitrobenzoic acid) (DTNB), ethylenediaminetetraacetic acid (EDTA), and reduced glutathione were purchased from Sigma Chemical Co, England. Indomethacin as "confortid" was purchased from Dumex, Denmark.

Amoxycillin was dissolved in water, whereas indomethacin was prepared in its solvent. The concentration of drugs was prepared in such a way that each rat received 0.5 ml/100 g body weight of drug solution. Amoxycillin was given intraperitoneally (i.p.) while indomethacin was injected subcutaneously (s.c.)

Male Wistar albino rats, of approximately the same age, weighing 200-250 g were obtained from the College of Medicine's Animal House, King Saud University, Riyadh, Saudi Arabia. The rats were maintained on a standard chow pellet diet and tap water ad libitum.


   Experimental Gastric Lesions Top


The animals were food-deprived and kept in individual cages with raised mesh bottom to prevent coprophagia. They were allowed free access to water. After 24 hours, the rats were randomly allocated to groups of six or eight animals in each group, and water was withdrawn. The groups were then subjected to one of the following experiments.

Ethanol-Induced Gastric Lesions. Gastric mucosal injury was induced by the oral administration of 1 ml of 100% ethanol per rat and the animals were sacrificed one hour later under ether anesthesia. Immediately after opening the stomach by cutting along the greater curvature, the stomach was pinned on a cork board, lightly rinsed with saline, and the examination of gastric lesions was carried out under an illuminated stereomicroscope. The gastric lesions were identified by an independent observer unfamiliar with the protocol and scored according to the method described by Schiantarelli et al [14] . The sum of the scores in each group of rats was divided by the number of animals and expressed as mean score for lesions. In test animals, amoxycillin (12.5­100 mg/kg, i.p.) was given 30 minutes before the administration of ethanol. Controls received the same volume of distilled water i.p. In some experiments, indomethacin (10 mg/kg, s.c) was administered one hour before the administration of ethanol to both control and treated groups.

Determination of Nonprotein Sulphydryl (NP-SH) Groups. In these experiments, following the same drug treatment schedules as described above, gastric glandular NP-SH concentration was measured according to the method of Sedlak and Lindsay[15] Briefly, the glandular part of the stomach was cut, weighed and homogenized in ice-cold 0.02 MEDTA to give 5% homogenates. Aliquots of 5 ml of the homogenates were mixed in 15-m1 test tubes with 4 ml of distilled water and 1 ml of 50% trichloroacetic acid (TCA). The tubes were shaken intermittently for 15 minutes and centrifuged at 3000 x g for 10/minutes. Two milliliters of supernatant were mixed with 4 ml of 0.4 M Tris buffer at pH 8.9; 0.1 ml of DTNB was added and the sample was shaken. The absorbance was read within five minutes of addition of DTNB at 412 nM against a reagent blank (with no homogenates) in a spectrophotometer (Perkin-Elmer, Lamda 5). The final NP-SH concentrations were calculated by comparing the absorbance of test with calibration curve prepared by using reduced glutathione solution and expressed as µmole per gram of glandular tissue.


   Measurement of Reactive Oxygen Metabolites Production Top


Chemiluminescence Measurement. The principle of the chemiluminescence (CL) assay is the oxidation of luminol by reactive oxygen species produced during phagocytosis. This was carried out according to previously reported methods [16],[17] . Briefly, the blood was drawn from healthy human volunteers and the polymorphonuclear leukocytes (PMNs) were separated, counted and the viability was determined as described previously [16],[17] . The reaction mixture consisted of 0.1 ml of isolated PMNs (5 x 10 6 /ml), 0.2 ml luminol (10 -5 M), 0.5 ml PBS (Phosphate - buffered saline) to which 0.2 ml of soluble PMA (2 ng/ml) was added. The light output in millivolt (mV) was immediately read and continuously recorded on an LKB (Wallac) chart recorder for a period of 30 minutes. The maximum CL response observed was taken. The effect of the drug on the luminol­dependent CL was determiend following addition of different concentrations of amoxycillin (0.312 - 5 mg/ml) to the cells prior to stimulation by PMA at 37°C and was measured in a luminometer (LKB 1251, Wallac). The results were expressed as CL maximum peak response in mV.


   Statistical Analysis Top


The results are presented as mean + S.E.M. Statistically significant differences between means were calculated by Unpaired Student's t-test or by analysis of variance (ANOVA) as appropriate.

A probability of P < 0.05 was considered significant.


   Results Top


Ethanol-Induced Gastric Lesions

Administration of ethanol resulted in the production of gastric mucosal lesions consisting of elongated dark bands generally parallel to the long axis of the corpus of the stomach. Pretreatment with amoxycillin attenuated ethanol-induced gastric lesions in a dose-dependent manner [Table - 1].

Effect of Pretreatment with Indomethacin on Amoxycillin-induced Gastric Protection

Prior treatment of animals with indomethacin slightly aggravated ethanol-induced gastric lesions. However, indomethacin pretreatment greatly reduced the gastric protection by amoxycillin against ethanol-induced gastric mucosal injury [Table - 1].

Effect of Amoxycillin on Gastric Mucosal NP-SH Content

The gastric mucosal NP-SH content was significantly depleted after the administration of ethanol. Amoxycillin alone did not produce any significant change in NP-SH levels in the stomach of rats which were not exposed to ethanol. However, treatment with amoxycillin significantly inhibited ethanol-induced depletion of NP-SH levels and restored it towards control values [Table - 2].

Effect of Amoxycillin on the Luminol-Dependent Chemiluminescence (CL) Responses of PMNs Stimulated with PMA

Amoxycillin dose-dependently inhibited PMA­stimulated CL responses of isolated human PMNs [Table - 3]. Amoxycillin, in the concentrations used, did not induce CL response of unstimulated PMNs in the presence of luminol. Similarly, the viability of the cells was unaffected in the presence of various concentrations of amoxycillin (data not shown).


   Discussion Top


This study demonstrates that the antimicrobial agent, amoxycillin, significantly attenuates ethano­induced gastric lesions in rats. Furthermore, it furnishes data that elucidates the potential mechanisms of amoxycillin-induced gastric protection. These results confirmed the previously published reports that amoxycillin possesses antioxidant and cytoprotective properties [12],[13] .

Amoxycillin exerts a dose-dependent inhibitory action on gastric mucosal lesions induced by ethanol. The fact that pretreatment of rats with a dose of indomethacin which is known to inhibit PGs biosynthesis [18] , reduced the protective effects of amoxycillin against ethanol-induced gastric injury may suggest that the endogenous release of mucosal PGs is a prerequisite for the protective effect of the drug. This finding is consistent with a previously published report [13] . In this context, PGs are known as cytoprotective agents and have been implicated as a defensive factor for the protection against gastroduodenal injuries [19],[20] including those induced by ehtanol in rats [20] .

Along with PGs, NP-SH have also been implicated in the defensive mechanism of gastric mucosal injury. Thus, gastric mucosal injury has been shown to be associated with a depletion of NP­SH concentration in the gastric mucosa of experimental animals and in humans, while its restoration to a critical level affords protection [21],[22],[23],[24] .

Furthermore, the inability of cytoprotective PGs to exert their effect in the presence of SH-blockers suggests that thiol groups may play an important role in mucosal defense [25] . In the present study, pretreatment with amoxycillin dose-dependently reversed ethanol-induced depletion of NP-SH and restored the level towards normal. These findings suggest that NP-SH may be involved in the gastric protective effect of amoxycillin.

There is evidence to suggest that oxygen derived free-radicals (ODFRs) are involved in the pathogenesis of gastric lesions induced by ethanol [26],[27],[28],[29] . Besides the animal studies, ODFRs have also been implicated in the pathogensis of human gastroduodenal diseases. Thus, increased free radical activities have been reported to be present in plasma [30] and in duodenal biopsies of duodenal ulcer patients [31] . Furthermore, H. Pylori infection causes enhancement of free radical activities implicating the role of H. pylori in the pathogenic mechanisms [32],[33] . The ability of amoxycillin to inhibit PMA-stimulated luminol dependent CL response of PMNs suggest an antioxidant effect of amoxycillin in-vitro. This finding corroborates the observation of Hao et al [12] who also reported an antioxidant mechanism of action of amoxycillin against reserpine-induced gastric lesions. Thus, the mechanism of gastric protection of amoxycillin against ethanol-induced gastric lesions may be, at least in part, due to an antioxidant effect.

In conclusion, this study demonstrates that amoxycillin possesses gastric protection effects against ethanol-induced gastric lesions and confiurus the gastroprotective effect of amoxycillin. The mechanisms of gastric protection afforded by amoxycillin may be attributed to: a) prevention of ethanol-induced mucosal PGs depletion b) prevention of ethanol-induced depletion of gastric NP-SH concentrations; and c) antioxidant effects.

 
   References Top

1.Labenz J, Borsch G. Evidence for the essential role of Helicobacter pylori in gastric ulcer disease. Gut 1994;35:19-22.  Back to cited text no. 1    
2.Graham DY, Go MF. Helicobacter pylori. Current status. Gastroenterology 1993;105:279-82.  Back to cited text no. 2    
3.Dixon MF. Helicobacter pylori and peptic ulceration histopathological aspects. J Gastroenterol Hepatol 1991;6:125-30.  Back to cited text no. 3  [PUBMED]  
4.Colgan JG, Gilligan D, Humphries H. Campylobacter pylori and recurrence of duodenal ulcers: a 12-month follow up study. Lancet 1987;ii:1109-11.  Back to cited text no. 4    
5.Marshall BJ, et al. Perspective double-blind trial of duodenal ulcer relapse after eradication of campylobacter pylori. Lancet 1988;ii:1437-42.  Back to cited text no. 5    
6.Graham DY, et al. Effect of treatment of Helicobacter pylori infection on the long-term recurrence of gastric or duodenal ulcer. A randomized, controlled study. Ann Intern Med 1992;116:705.  Back to cited text no. 6    
7.Axon ATR. Helicobacter pylori therapy. Effect on peptic ulcer disease. J Gastroenterol Hepatol 1991;6:131-7.  Back to cited text no. 7    
8.Labenz J, Gyenes E, Ruhl GH, Borsch G. Omeprazole plus amoxycillin. Efficacy of various treatment regimens to eradicate Helicobacter pylori. Am J Gastroenterol ­1993;88:491-5.  Back to cited text no. 8    
9.Hentschel E, et al. Effect of ranitidine and amoxycillin plus metronidazole on the eradication of Helicobacter pylori and the recurrence of duodenal ulcer. N Engl J Med 1993;328:308-12.  Back to cited text no. 9  [PUBMED]  [FULLTEXT]
10.Drake IM, Axon TTR, Clarke AHE. Ranitidine in a twice daily triple-therapy regimen for the eradication of Helicobacter pylori. Fur J Gastroenterol Hepatol 1996;8:1169-73.  Back to cited text no. 10    
11.Fang G, Li YN, Ye SM. Protective effect of amoxycillin on duodenal ulceration experimental and clinical studies. J Gastroenterol Hepatol 1993;8(suppl 2):S200.  Back to cited text no. 11    
12.Hao ZM, Zhang SZ, Cheng ZZ, Li LH, Bai CX. The protective effect and mechanism of amoxycillin against reserpine-induced gastric ulceration in rats. J Gastroenterol Hepatol 1993;8(suppl.2): S 146.  Back to cited text no. 12    
13.Lam SK, Cho CH, Chen BW, Lai KC, Chin.- CK, Ho CS, Li YN. Gastric cytoprotection by amoxycillin in rat. J Gastroenterol Hepatol 1994;9:514-8.  Back to cited text no. 13    
14.Schiantarelli P, Cadel S, Falco GC. Gastroprotective effects of morniflumate, an esterified anti inflammatory drug. Arzneim Forsch 1984;34:885-90.  Back to cited text no. 14    
15.Sedlak J, Lindsay RH. Estimation of total, protein bound and nonprotein sulfhydryl groups in tissue with Ellman's reagent. Anal Biochem 1968;25:192-5.  Back to cited text no. 15  [PUBMED]  
16.Al-Mofleh IA, Al-Tuwaijri AS, Mahmoud AA, Alam M. Entameba histolytica depresses chemiluminescence in stimulated human polymorphonuclear leukocytes. Int J Immunopharmac 1989;5:529-36.  Back to cited text no. 16    
17.AI-Tuwaijri AS, Al-Dohayan AD. The pattern of respiratory burst of leucocytes in patients with Echinococcus granulosus. Microbios 1995;83:167-74.  Back to cited text no. 17    
18.Robert A, Nezamis JE, Lancaster C, Davis JP, Field SO, Itanchar. AJ. Milder irritants prevent gastric necrosis through "adaptive cytoprotection" mediated by prostaglandin. Am. J. Physiol, 1983;245:G113-G21.  Back to cited text no. 18    
19.Aase S. Disturbances in the balance between aggressive and protective factors in the gastric and duodenal mucosa. Scand J Gastroenterol 1989;24(suppl.163):17-23.  Back to cited text no. 19    
20.Robert A, Nezamis JE, Lancaster C, Hanchar AJ. Cytoprotection by prostaglandins in rats. Prevention of gastric necrosis produced by alcohol, HCl, NaOH, hypertonic NaCl, and thermal injury. Gastroenterology 1979;77:433-43.  Back to cited text no. 20    
21.Szabo S, Brown A. Prevention of ethanol-induced vascular injury and gastric mucosal lesions by sucralfate and its components: possible role of endogenous sulfhydryls. Proc Soc Exp Bio Med 1987;185:493-7.  Back to cited text no. 21    
22.Rogers C, Brown A, Szabo S. Gastric mucosa protection by new aryl sulfhydryl drugs. Dig Dis Sci 1988; 33:324-9.  Back to cited text no. 22  [PUBMED]  
23.Ali ATMM. The role of nitric oxide and sulfhydryls in gastric mucosal protection by sodium cromoglycate in rats. J Pharm Pharmacol 1995;47:739-43.  Back to cited text no. 23    
24.Loguercio C, Taranto D, Beneduce F, Blanco CV, de Vincentiis A. Glutathione prevents ethanol-induced gastric mucosal damage and depletion of sulfhydryl compounds in humans. Gut 1993;34:161-5.  Back to cited text no. 24    
25.Szabo S, Trier JS, Frankel PW. Sulfhydryl compounds may mediate cytoprotection Science 1981;214:200-2.  Back to cited text no. 25    
26.Szelenyi I, Brune K. Possible role of oxygen free radicals in ethanol-induced gastric mucosal damage in rats. Dig Dis Sci 1988;33:865-71.  Back to cited text no. 26  [PUBMED]  
27.Salim AS. Role of oxygen-derived free radicals in mechanism of acute and chronic duodenal ulceration in the rat. Dig Dis Sci 1990;35:73-9.  Back to cited text no. 27  [PUBMED]  
28.Ligumsky M, Sestieri M, Okon E, Ginsberg 1. Antioxidants inhibit ethanol-induced gastric injury in the rat. Scand J Gastroenterol 1995;30:854-60.  Back to cited text no. 28    
29.Moghadasian MH. Ethanol-induced gastrointestinal damage. Influence of endogenous antioxidant compounds and gender. Dig Dis Sci 1996;41:791-7.  Back to cited text no. 29    
30.Jankowski J, Bridges AB, Scott N, Wormsley KG, Belch JJF. Circulating free-radical markers and peptic ulcer disease. Eur J Gastroenterol Hepatol 1991;3:823-8.  Back to cited text no. 30    
31.Davies GR, Simmonds NJ, Stevens TRJ, Grandison A, Blake DR, Rampton DS. Mucosal reactive oxygen metabolite production in duodenal ulcer disease. Gut 1992;33:1467-72.  Back to cited text no. 31    
32.Nielsen H, Andersen LP. Activation of phagocyte oxidative metabolism by Helicobacter pylori. Gastroenterology 1992;103:1747-53.  Back to cited text no. 32  [PUBMED]  
33.Davies GR, Simmonds NJ, Stevens TRJ, et al. Helicobacter pylori stimulates antral mucosal reactive oxygen metabolite production in-vivo. Gut 1994;35:179-85.  Back to cited text no. 33    

Top
Correspondence Address:
Othman Abdullah Al Swayeh
Department of Medical Pharmacology (31), College of Medicine, King Saud University, P.O. Box 2925, Riyadh 11461
Saudi Arabia
Login to access the Email id

Source of Support: None, Conflict of Interest: None


PMID: 19864775

Rights and PermissionsRights and Permissions



 
 
    Tables

  [Table - 1], [Table - 2], [Table - 3]



 

Top
 
  Search
 
  
  
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
    Email Alert *
    Add to My List *
* Registration required (free)  


    Abstract
    Materials and Me...
    Experimental Gas...
    Measurement of R...
    Statistical Analysis
    Results
    Discussion
    References
    Article Tables

 Article Access Statistics
    Viewed3931    
    Printed128    
    Emailed2    
    PDF Downloaded0    
    Comments [Add]    

Recommend this journal