International Journal of Pharmacognosy and Phytochemical Research 2013; 5(2); 113-119
Gastroprotective Efficacy of Folic Acid and Omeprazole in
1Samar Morjan , *1Shaza Al Laham , 2Rana Atieh
1Pharmacology & Toxicology Department - Faculty of pharmacy- Damascus University- Damascus-Syria
2Histopathological Department - Medicin faculty- Damascus University- Damascus-Syria
ABSTRACT Gastric and intestinal mucosal damage is the commonest adverse effect of NSAIDs. Their use is associated with a significant risk of hemorrhage, erosions, and perforation of both gastric and intestinal ulcers. NSAID-induced ulcers can be prevented largely through co-administration of a proton pump inhibitor to block acid secretion in the stomach. Also there is a role for folic acid in the attenuation of indomethacin induced gastric ulceration. Study the effect of Folic acid and its association with the antisecretory drug Omeprazole (Proton pump inhibitor) for their abilities to protect gastric mucosa against the indomethacin-induced gastric ulcer. The experiments had been done on 10 white wistar rats for each group. Gastric ulcer was induced by administration of indomethacin (20 mg/kg i.p.). Folic acid (2 mg/kg, orally) has been given for the first group, while Omeprazole (20 mg/rat, orally) has been given for the second group and Folic acid (2 mg/kg, orally) with Omeprazole (10 mg/rat, orally) has been given for the third group as a repeated administration (once daily for 7 days). The gastric ulcers in stomach's rat were examined histological and macroscopical .The ulcer Index and protective Index were calculated. Then the glycoproteines of stomach's mucus gel was measured by spectrophotometer. The combination-treated group (Folic acid and Omeprazole ) gave significant increase in the amount of gastric mucosa as compared to Indomethacin group and in comparing to each drug alone the protective Index was increased while ulcer Index retreat. It could be concluded that the combination-treated groups afford a good gastro-protective potential against the gastric ulceration induced by indomethacin better than each drug alone. The antioxidant effects of folic acid and omeprazole are involved and ameliorating the oxidative stress induced by indomethacin in the gastric mucosa. Keywords: Ulcer, Omeprazole, Folic acid. INTRODUCTION
degraded at low pH and must be given in enteric-coated
Peptic ulcer occurs when there is an imbalance between the
granules1. The coating is removed in the alkaline
damaging effects of gastric acid and pepsin, and the
duodenum, and the prodrug, a weak base, is absorbed and
defense mechanisms, which protect the gastric and
transported to the parietal cell canaliculus. There, it is
duodenal mucosa from these substances1. The danger of
converted to the active form. Clinical studies have shown
epithelial arrosion and subsequent ulcer formation exists
that PPIs reduce the risk of bleeding from an ulcer caused
whenever the protective and reparative mechanisms are
weakened and/or the chemical attack by the acid–pepsin
Folic acid (or folate), is a water-soluble vitamin8. Folic
mixture is too strong and persists for too long2. The
acid is used to prevent or cure deficiency of folate which
majority of gastric ulcers can be attributed to either H.
is due either to a decreased supply or to an increased
pylori or NSAID-induced mucosal damage3, particularly
requirement. Deficiency of folic acid leads to a
in the elderly1. NSAIDs cause serious complications only
megaloblastic anaemia because it is necessary for the
in a small fraction of NSAID users. Hence, NSAID
production of purines and pyrimidines, which are essential
prophylaxis is advised for those older than 654, cases of
precursors of deoxyribonucleic acid (DNA)24. Folate
cardiac disease5, those with previous history of ulcers or
modulates a number of disorders as a result of its anti-
upper GI bleed4,5, and those using anticoagulants and
gastroprotective activity of folic acid supplementation at
Recent studies suggest that NSAID-induced ulcers in at-
the basal requirement supplemental dose of 2 mg/kg diet
risk patients can be prevented largely through co-
against the lipid peroxidative activity of indomethacin was
administration of a proton pump unhibitor6, such as
Omeprazole that bind to the H+/K+-ATPase enzymesystem (proton pump) of the parietal cell and suppress the
MATERIALS AND METHODS
secretion of hydrogen ions into the gastric lumen7. This
Animals: Fifty male albino rats of the Wistar strain
irreversibly inactivates the enzyme causing profound
weighing between 180-250 g were used for this study. The
inhibition of acid secretion: a single 20 mg dose reduces
animals were separated randomly into ten cages of five rats
gastric acid output by 90% over 24 h. Omeprazole is
each where they were kept for four weeks before the start
*Author for correspondence: Email: [email protected]Shaza Al Laham et.al./ Gastroprotective Efficacy of…
Table 1: Effect of folic acid, omeprazole and combination between them on ulcer number, ulcer acuity, ulcer index,and preventive index in indomethacin- (INDO-; 20 mg/kg, i.p.) induced gastric injury. Parametric data were expressed as mean ± S.E.M. P < 0.05. As compared to control (CONT) (**). As compared toINDO (*).
Figure 3: Pin-point petechial hemorrhages
animals from contracting disease. They were fed with
standard commercial rat pellets and allowed water ad
of the experiment. The animals were housed understandard conditions of temperature (23 ± 2°C), humidity(55 ± 15%) and 12 hour light (7.00 am - 7.00 pm). The
cages were constantly cleaned in order to prevent the
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Table 2: Effect of folic acid, omeprazole as well as their combination on indomethacin-induced (INDO; 20 mg/kg, i.p.)gastric injury histoligically. Values given as mean+SEM. P < 0.05. As compared to control (CONT) (**),As compared to INDO (*).
Figure 4: Histological section of gastric mucosa in a rat from Group 1 (NORMAL). Microscopic grade: 0. Note: Thereis no disruption to the surface of epithelium with neither edema nor leucocytes infiltration of the submucosal layer(H&E stain, 20x magnification).
Grouping: The animals were divided into five groups of
Operative procedure13:After seven days of treatment with
the appropriate drug for each group, animals were
Group One (NORMAL): Animals were treated with
normal saline for seven days. They were called the
The rat was anesthetized and a midline incision was made
and the stomach is removed, then the stomach was opened
Group Two (INDO): Animals were treated with normal
along the greater curvature, stretched moderately by
saline for seven days before indomethacin (CSPC Ouyi
pinning on a cork board, and then the gastric mucosa was
pharmaceutical.co) administration (20 mg/kg).
examined by naked eye and magnifying lens to:
Group Three (FOLIC): Animals were treated with 2
mg/kg of folic acid (Ibn Sina laboratories) for seven
*determine the ulcer acuity for each group. Gastric lesions
days before indomethacin administration (20 mg/kg).
were scored according to the following system:
Group Four (OMEPRAZOLE): Animals were treated
0: no lesion; 1 : <5 lesions, all <2 mm; 2 : <5 lesions, at
with omeprazole (ASIA Pharmaceutical Industries) for
least one lesion >2 mm; 3 : 5- 10 lesions, all <2 mm; 4 : 5-
seven days (20 mg/rat)11 then indomethacin was
10 lesions, at least one lesion >2 mm; 5 : >10 lesions, all
administrated (20 mg/kg). This group served as the
<2 mm; 6 : >10 lesions, at least one lesion >2 mm14.
Each lesion was considered as an ulcer to calculate the
Group Five (FOLIC + OMEPRAZOLE): Animals were
ulcer index (UI) as described by Robert 15:
treated with omeprazole (10 mg/rat) + folic acid (2
mg/kg) for seven days then indomethacin was
a : percentage of animals with ulcers / 10
The route of administration for folic acid was oral. Folic
c : average of number of ulcers per group animals
acid was dissolved in normal saline to give a suspension.
Then the preventive index (P.I.) of a given drug was
Omeprazole pellets were administrated by feeding tube
calculated by the equation of Hano et al 16.
without dissolving to reach the duodenum in this form and
U.I. of IND group - U.I. of pretreated group
protect them from degradation at low pH in the stomach.
P.I. = ------------------------------------------------------X 100
Ulcer Induction12: Animals were singly housed and fasted
Histopathological techniques: Each stomach was fixed
for 36h in widemesh bottomcages, allowed free access to
with 10% formalin solution for 24 hours. After fixation,
water except for the last hour before the last dose of the
five specimens were taken from each stomach. Then
medication. Rats were injected intraperitoneally by
sections were stained with conventional EH stain; at least
indomethacin (20 mg/kg) 1 h after the last dose of the
four sections were prepared from each animal. The stained
medication and euthanized under deep ether anesthesia 4 h
sections were examined under light microscope and the
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Figure 5: Histological section of gastric mucosa in a rat
Figure 6: Histological section of gastric mucosa in a rat
from Group 2 (INDO). Microscopic grade: 3. Note: There
from Group 3 (FOLIC). Microscopic grade: 3. Note:
There is ulceration with inflammation and neutrophiles
inflammation (H&E stain, 20 x magnifications).
infiltration (H&E stain, 40 x magnifications).
Figure 7: Histological section of gastric mucosa in a rat
Figure 8: Histological section of gastric mucosa in a rat
from Group 4 (OMEPRAZOLE). Microscopic grade: 2.
from Group 5 (FOLIC + OMEPRAZOLE). Microscopic
Note: There is surface mucosal abrasion with old
grade: 2. Note: There is mucosal edema and Congestion
haemorrhages and hemosiderin precipitation (H&E stain,
(H&E stain, 20 x magnifications).
The severity and the degree of mucosal damage were
All obtained values were expressed as mean + standard
assessed according to modified Sedny scale, so that the
error of mean (SEM). By using Mann-Whitney test the
following grades were obtained: Grade (0): no mucosal
proportion of histopathological changes and ulcer acuity in
lesions; Grade (1): mucosal edema, congestion, and
various groups of animals were compared. While the
neutrophils infiltration; Grade (2): surface mucosal
significance of differences between means of ulcers
erosion. Grade (3): ≤ 2 Gastric ulcers. Grade (4): > 2
number and mucin content were calculated using the
student’s t-test. P-values < 0.05 were considered
Mucin Content Determination:The gastric mucin was
significant. All analysis utilized Prizm4.
determined according to the method described byWinzler17. Briefly, to diluted samples orcinol (1.6%) and
sulphuric acid (60%) were added, vortexed, and boiled for
Macroscopic study: The macroscopic findings of the
10min. Mixtures were cooled in ice-cold water to stop the
opened stomach are shown in Fig. 1. Numerous, tiny, pin-
reaction and the absorbance was measured at 425 nm.
point petechial hemorrhages (figure 3) and large erosions(figure 2) were observed in the indomethacin administered
STATISTICAL ANALYSIS
group (INDO, Group 2). Folic acid alone (FOLIC, Group
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Table 3: Effect of folic acid, omeprazole as well as their combination on mucin secretion in indomethacin-induced(INDO; 20 mg/kg, i.p.) gastric injury. Values are means ± SEM; comparisons were carried out using Student t-test, P< 0.05. As compared to control (CONT)(**); INDO (*). Values given as mean+SEM. P < 0.05. As compared to control (CONT) (**), INDO (*).
3) had almost no effects on the stomach, and the
ulcer index, and decrease mucin content (75%) as
coadministration of folic acid with omeprazole inhibited
compared to control group. Research works on the effect
indomethacin-induced ulcer formation (FOLIC +
of indomethcin on the gastric mucosa are in agreement
with our results. In a previous study, indomethacin
Histological evaluation of gastric lesions
decrease gastric mucin concentration by 55.7% and
Group 1: Most rats in the control group revealed normal
increase ulcer index12. Histological observation showed
squamous gastric epithelium (figure 4). Only two of them
comparatively extensive damage to the gastric mucosa,
showed a mild degree of congestion of blood vessels.
and oedema and leucocytes infiltration of the submucosal
Group 2: Histological observation of indomethacin
layer in most of the animals in indomethacin group. There
induced gastric lesions in ulcer control group pre-treated
was a statistically significant difference on gastric erosion
with normal saline only, showed comparatively extensive
score between indomethacin group and control group (p
damage to the gastric mucosa, and oedema and leucocytes
infiltration of the submucosal layer (Figure 5). Most rats in
The molecular basis for the gastrointestinal toxicity of
indomethacin group experienced the gastric mucosal
NSAIDs is widely believed to their inhibitory activity
against cyclooxygenase, which causes them to block the
Group 3: Rats that received pretreatment with only folic
production of prostaglandins18. The physiological
acid didn’t have enough protection of the gastric mucosa
function of mucosal prostaglandins is cytoprotective, by
as compared to indomethacin group. Six rats in the group
inhibiting acid secretion, promoting the secretion of mucus
of folic acid (2 mg/kg) had ulcers in the stomach and
and strengthening resistance of the mucosal barrier to
leucocytes infiltration of the submucosal layer.
back-diffusion of acid from the gastric lumen into the
Group 4: Rats that received pretreatment with omeprazole
submucosal tissues where it causes damage1. NSAIDs
had comparatively better protection of the gastric mucosa
significantly decreased the mucosal prosta-glandin E2
as seen by reduction in ulcer area, reduced or absent
(PGE2) concentration. Charac¬teristically, the damage
submucosal edema and leucocytes infiltration (Figure 2).
was observed along the long axis of the stomach and
Group 5: The combination between folic acid and
consisted mostly of hemorrhagic lesions, with a few non-
omeprazole showed cytoprotective effects. Most rats in
hemorrhagic lesions22. Suppression of prostaglandin
this group experienced the gastric mucosal erosion with the
synthesis is associated with reduction of gastric mucosal
score 2. Mean gastric erosion scores were demonstrated in
blood flow, disturbance of microcirculation, decrease in
Table 2. Pretreatment with Omeprazole and folic acid 1
mucus secretion, lipid peroxidation, and neutrophil
hour before administration of indomethacin resulted in a
activation, which are involved in the pathogenesis of
decrease in mean gastric erosion score. In addition, there
gastrointestinal mucosal disorders18. All NSAIDs, except
was a statistically significant difference between the
aspirin, increased gastric motility at ulcerogenic doses,
combination group and indomethacin group (p <0.05).
leading to the development of gastric lesions. Gastric
Mucin Content Determination: Indomethacin, as shown in
Table 3, leveled off mucin concentration in the gastric
especially at specific sites on mucosal folding, leading to
juice by 75% while folic acid, as well as omeprazole and
their combination elevated it (24%, 79%, 95%),
interaction. In addition, indomethacin caused oxyradical
respectively, as compared to the indomethacin-treated rats.
production and lipid peroxidation in the gastric mucosa,probably resulting from the ischemic-reperfusion changes
DISCUSSION
due to rhythmic hypercontraction of the stomach that is
Experimental studies have demonstrated that nonsteroidal
mediated by a vagal-cholinergic mechanism22.
anti-inflammatory drugs (NSAIDs) such as indomethacin
Stress, nonsteroidal anti-inflammatory drugs, and H. pylori
are capable of producing injury to gastrointestinal mucosa
cause mucosal damage through a number of mechanisms,
in experimental animals and humans18. In the present
of which some reactive oxygen species (ROS) such as O2•-
study, injecting indomethacin intraperitoneally (20 mg
and OH• are now considered to be one of the major
/kg) induced raise in ulcer acuity, number of ulcers and
causative factors for mucosal lesions through oxidativedamage. Lipid peroxidation, an important parameter for
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OH•-induced oxidative damage of membrane, is increased
In addition to the gastroprotective effect of omeprazole
in gastric lesions caused by ethanol, indomethacin, and
through inhibiting gastric acid secretion, a recent study
water immersion stress. Increased lipid peroxidation,
showed antioxidant and antiapoptotic role of omeprazole
increased protein oxidation, and decreased glutathione
to block gastric ulcer through scavenging of endogenous
level are also evident in restraint cold stress-induced
hydroxyl radical associated lipid peroxidation and protein
gastric lesions as a result of oxidative damage caused by
oxidation, indicating that its antioxidant role plays a major
the significant generation of OH• . Recent studies also
part in preventing oxidative damage. omeprazole prevents
indicate that programmed cell death or apoptosis plays a
loss of membrane permeability and dysfunction of the
significant role in gastric ulceration. Gastric mucosal
cellular proteins, leading to survival of the functionally
lesions caused by stress, indomethacin, ethanol, and H.
active cells. Moreover, it offers an antiapoptotic effect by
pylori are also due to increased cell death by apoptosis 19.
blocking DNA fragmentation during ulceration19.
The gastroprotective activity of folic acid supplementation
As a result, the effect of co-administration of folic acid and
at the basal requirement supplemental dose of 2 mg/kg diet
omeprazole in preventing indomethacin-induced gastric
against the lipid peroxidative activity of indomethacin was
ulcer can be explained through their antioxidant role. So
mentioned10. Folate, an important factor in the de novo
they are able to attenuate oxidative stress induced after
synthesis of purines, and thymidine, Deoxyribonucleic
indomethacin administration. Indomethacin produces an
acid (DNA) stability, and apoptosis, is able to attenuate the
increase in formation of ROS that catalyze lipid
development of gastric ulcer. Increase the superoxide
peroxidative and gastric epithelial damage, while folic acid
dismutase and mucus concentration observed in the folic
and omeprazole play antioxidant and antisecretory roles,
acid pre-treated group suggests gastroprotective activity of
scavenge ROS and reduce their harmful effects thus as a
folates, because they are scavengers which mop up and
result prevent gastric ulcer formation.
resist free radicals predisposing the stomach toinflammation. Moreover, this is underscored by a decrease
CONCLUSIONS
in the MDA concentration observed in this group of
The combination between folic acid and omeprazole have
animals. This could mean that folate inhibits the lipid
preventive effect against indomethacin-induced gastric
peroxidative activity of indomethacin 9.
ulcer in rats. Using folic acid (2 mg/kg) for seven days is
Folic acid (2 mg/kg) was used in previous studies for 21
ineffective in preventing indomethacin-induced gastric
days. It showed a gastroprotective activity according to its
the antioxidative and antisecretory properties 9, 10. Whilein our study it was used in that dose for 7 days and it didn’t
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Diplomate American Board of Allergy and Immunology IMMUNOTHERAPY – HYPOSENSITIZATION – ALLERGY SHOTS Allergic hyposensitization therapy is a well-established form of medical treatment that attempts to decrease the allergy sufferer’s allergic sensitivity. It entails giving the patient repeated injections of the allergenic materials to which he is most sensitive. The offending substances
Brand Management in Pharmaceuticals James G. Conley1, Morton I. Kamien2 and Israel Zang3 Extended Abstract This paper is concerned with trade marks and patented products. While patent protection is limited in time, trademarks are practically indefinite (Conley 2005). Hence, Conley and Szobocsan (2001) suggested that trade marking a product, protected by a patent, can create a product v