Clinical efficacy of esomeprazole in the prevention and healing of gastrointestinal toxicity associated with NSAIDs in elderly patients

Protective effect of luteolin on indomethacin-induced gastric ulcer in rats

BACKGROUND

Long-term use of nonsteroidal anti-inflammatory drugs can lead to gastric ulcer. However, there are many side effects associated with the commonly used therapeutic agents for gastric ulcer.

AIM

To investigate the protective effect of luteolin (Lut) on indomethacin (IND)-induced gastric ulcer in rats and the underlying mechanisms.

METHODS

Forty male Wistar rats were randomly divided into a control group, a model group, and low-, medium-, and high-dose Lut groups, with eight rats in each group. A rat gastric ulcer model was established by intragastric administration of IND (40 mg/kg) for 14 d. The low-, medium-, and high-dose Lut groups were given 1 mg/kg, 10 mg/kg, and 100 mg/kg Lut by gavage for 14 d. The control group was given the same volume of carboxymethylcellulose. The macroscopic morphology of the gastric mucosa was observed visually. The pathological changes of the gastric mucosa were examined by HE staining. Apoptosis in the gastric mucosa was detected with the ApopTag Peroxidase In Situ Apoptosis Detection Kit. The levels of superoxide dismutase (SOD), reduced glutathione (GSH), and malondialdehyde (MDA) in the gastric mucosa were determined with commercial kits.

RESULTS

Lut administration could reduce IND-induced gastric ulcer in a dose-dependent manner, improve the pathological morphology of gastric mucosal tissues, reduce the apoptosis of gastric mucosal epithelial cells, increase the levels of SOD and GSH in gastric mucosal tissues, and decrease the level of MDA.

CONCLUSION

Lut can alleviate IND-induced gastric ulcer in rats, and the mechanism may be related to the inhibition of gastric epithelial cell apoptosis and antioxidant stress.

Simultaneous determination of naproxen and esomeprazole in beagle dog plasma by supercritical fluid chromatography-tandem mass spectrometry coupled with evaporation-free liquid-liquid extraction

In order to avoid a risk of gastrointestinal toxic caused by naproxen (NAP), esomeprazole (ESOM) is generally used clinically in combination. The present work was undertaken to simultaneously determine NAP and ESOM in beagle dog plasma, and evaluated their pharmacokinetic behaviors in beagle dogs. Herein, ethyl acetate was used to extract the samples by using a time-saving evaporation-free liquid-liquid extraction (EF-LLE) method, then the samples were analyzed by supercritical fluid chromatography tandem mass spectrometry (SFC-MS/MS). The optimal analysis conditions were achieved with an ACQUITY UPC2™ BEH column maintained at 50℃ and eluted completely within 2 min using supercritical carbon dioxide and methanol with a gradient elution mode. Due to the large differences in plasma concentrations between NAP and ESOM, celecoxib and diazepam were selected as dual-internal standards (IS). The mass transition ion pairs were m/z 231.2 → 185.0, 346.9 → 198.2, 285.1 → 193.1 and 382.2 → 281.2 for NAP, ESOM, diazepam (IS for NAP) and celecoxib (IS for ESOM), respectively. The concentration of NAP and ESOM were linear within the range of 0.1-100 μg/mL (r > 0.993) and 0.005-5 μg/mL (r > 0.996) in beagle dog plasma, and the accuracy and precision of intra-day and inter-day of all quality control samples were within ±15 %. It was a method with the feature of rapid, sensitive and high-throughput, and would be practical for determining NAP and ESOM in biological samples simultaneously and for assessing their pharmacokinetic behaviors in clinical studies.

Rosmarinic Acid Enriched Fraction from Perilla frutescens Leaves Strongly Protects Indomethacin-Induced Gastric Ulcer in Rats

Gastric ulcers are a common problem in upper gastrointestinal tract (GI) disorders. Nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the most aggressive factors leading to inducing gastric ulcers. Natural products with lower toxicity and safety are currently sought as a potential source to minimize the effect of the gastric ulcers. Perilla frutescens or Nga-mon (in Thai) leaves are rich in rosmarinic acid (RA), which has antioxidant, anti-inflammatory, and anticancer effects. This study investigates the protective effect of ethanolic extract (EE) and aqueous fraction (AF) from Perilla frutescens leaves, which are rich in RA, on indomethacin- (IND-) induced gastric ulcer in a rat model. The EE at the doses of 50 and 500 mg/kg body weight, AF at the doses of 50, 250, and 500 mg/kg body weight, or famotidine (a standard drug) were administered for 14 days prior to ulcer induction. The ulceration was performed by intragastric administration of IND. Gross gastric ulcers and biological and histological parameters were examined. The pretreatment with AF had more significant effects than EE, including reduced ulcer index, decreased gastric secretion volume and decreased acidity, but it had an elevated gastric pH relative to the IND-induced gastric ulcer. In a histopathological study, the EE and AF decreased mucosal ulcer, inflammatory infiltration, and degenerative lining cells. The IND-induced expression of inflammatory mediators was significantly attenuated with EE and AF. The experiment also remarkably showed the preservation of mucus and apoptosis protection of EE and AF on a gastric mucosal ulcer. The findings demonstrated that the EE and AF of perilla leaves were capable of protecting the stomach against gastric ulcers induced by IND through anti-inflammatory and antiapoptotic mechanisms that should be further investigated. It is suggested that Perilla frutescens leaf could be a potential alternative source of RA as a therapeutic agent and food supplement for NSAID-induced gastric injuries.

Healing and Antisecretory Effects of Aqueous Extract of Eremomastax speciosa (Acanthaceae) on Unhealed Gastric Ulcers

OBJECTIVE

This work investigated the healing and antisecretory effects of the aqueous extract of Eremomastax speciosa on "unhealed gastric ulcers" associated with gastric acid hypersecretion.

MATERIALS AND METHODS

"Unhealed gastric ulcers" were induced using indomethacin following the establishment of acetic-acid-induced chronic gastric ulcers. The extract (200 and 400 mg/kg, per os) was administered concomitantly with indomethacin (1 mg/kg, subcutaneously). The effects of the extract on both basal and histamine-stimulated gastric acid secretion were determined. Mucus secretion and oxidative stress parameters were measured, and histological assessment of ulcer healing was carried out.

RESULTS

The extract significantly promoted the healing process in rats subjected to "unhealed gastric ulcers" (82.4-88.5% healing rates). Treatment with the extract significantly reduced the basal (25.95-49.51% reduction rates) and histamine-stimulated (24.25-47.41%) acid secretions. The healing effect of the extract was associated with a significant (p < 0.05) increase of mucus secretion and concentrations of antioxidant enzymes compared with the controls. The extract at the highest dose showed normalization of the mucosa, without glandular destruction and with the disappearance of fibrosis and lymphocyte infiltration.

CONCLUSION

The abilities of the extract to increase mucus secretion, to reinforce antioxidant status, and to inhibit acid secretion would be some of the mechanisms by which this extract would accelerate the healing process in "unhealed gastric ulcers."

Pharmacogenomic testing: the case for CYP2C19 proton pump inhibitor gene-drug pairs

The use of proton pump inhibitors (PPIs) in the treatment of gastroesophageal reflux and related diseases is increasing, especially in the pediatric population. Prolonged use of PPIs has been associated with several adverse effects, including potentially life-threatening gastric and respiratory infections, which are related to dose or to the degree of gastric acid suppression. Genetic variation in the CYP2C19 gene gives rise to poor and extensive metabolizer phenotypes, which influence PPI clearance, efficacy and exposure. A recent paper linked lansoprazole-associated respiratory infections in children with the poor metabolizer phenotype. The case is made for implementing pharmacogenomic testing for the CYP2C19-PPI gene-drug pair and to dose accordingly in order to minimize PPI-associated infections.

Expression of PGE2 and COX in intestinal injury induced with non-steroidal anti-inflammatory drugs in rats: Implications for protective effects of drugs

AIM: To investigate the expression of prostaglandin E₂ (PGE₂), cyclooxygenase 1 (COX-1) and cyclooxygenase 2 (COX-2) in diclofenac sodium-induced intestinal injury in rats and to analyze their implications for protective effects of drugs.

METHODS: Thirty-two male Wistar rats were randomly and equally divided into four groups: a normal control group (given normal saline), a model control group (given diclofenac sodium), and two treatment groups (given Jinghua Weikang Jiaowan and esomeprazole, respectively). Except for the normal control group, intestinal injury was induced with diclofenac sodium in the other groups. Jinghua Weikang Jiaowan and esomeprazole were administered in the two treatment groups from the day before diclofenac sodium was given. Intestinal injury was observed by microscopy. The content of PGE₂ in the small intestine tissues was tested by ELISA. The expression of COX-1 and COX-2 proteins was detected by Western blot.

RESULTS: Compared to the normal control group, the morphological score increased significantly in the model control group (4.63 ± 0.52 vs 0.00 ± 0.00, P < 0.05); however, the morphological score was significantly lower in the two treatment groups than in the model control group (1.88 ± 0.99, 2.75 ± 1.28, both P < 0.05). Compared to the normal control group, the content of PGE₂ was significantly lower in the model control group (19.32 ng/L ± 8.22 ng/L vs 36.64 ng/L ± 3.27 ng/L, P < 0.05); however, the content of PGE₂ increased significantly in the two treatment group increased significantly compared to the model control group (29.51 ng/L ± 7.61 ng/L, 29.20 ng/L ± 7.51 ng/L, both P < 0.05). The expression level of COX-1 was significantly lower in the model control group than in the normal control group (0.47 ± 0.32 vs 0.78 ± 0.39, P < 0.05); however, the expression of COX-1 increased significantly in the treatment group compared to the model control group (1.29 ± 0.63, 1.53 ± 1.00, both P < 0.05). Compared to the normal control group, the expression of COX-2 increased significantly in the model control group (1.00 ± 0.72 vs 0.00 ± 0.00, P < 0.05); however, the expression of COX-2 increased significantly in the Jinghua Weikang Jiaowen treatment group (6.86 ± 9.81, P < 0.05). Compared to the model control group, the expression of COX-2 increased in the esomeprazole treatment group, but the difference was not significant (2.59 ± 2.87, P > 0.05).

CONCLUSION: Decreased content of PGE₂ in the small intestine tissue may be associated with diclofenac sodium-induced small intestinal injury. Jinghua Weikang Jiaowan and esomeprazole exert preventive effects against diclofenac sodium-induced intestinal injury possibly by raising the level of PGE₂. The therapeutic effect of Jinghua Weikang Jiaowan may be related to high expression of COX-1 and COX-2, and that of esomeprazole may be related to the high expression of COX-1.

H(2)S-releasing aspirin protects against aspirin-induced gastric injury via reducing oxidative stress

The aim of this study was to examine the effect of ACS14, a hydrogen sulfide (H(2)S)-releasing derivative of aspirin (Asp), on Asp-induced gastric injury. Gastric hemorrhagic lesions were induced by intragastric administration of Asp (200 mg/kg, suspended in 0.5% carboxymethyl cellulose solutions) in a volume of 1 ml/100 g body weight. ACS14 (1, 5 or 10 mg/kg) was given 30 min before the Asp administration. The total area of gastric erosions, H(2)S concentration and oxidative stress in gastric tissues were measured three hours after administration of Asp. Treatment with Asp (200 mg/kg), but not ACS14 (430 mg/kg, at equimolar doses to 200 mg/kg Asp), for 3 h significantly increased gastric mucosal injury. The damage caused by Asp was reversed by ACS14 at 1-10 mg/kg in a concentration-dependent manner. ACS14 abrogated Asp-induced upregulation of COX-2 expression, but had no effect on the reduced PGE(2) level. ACS14 reversed the decreased H(2)S concentrations and blood flow in the gastric tissue in Asp-treated rats. Moreover, ACS14 attenuated Asp-suppressed superoxide dismutase-1 (SOD-1) expression and GSH activity, suggesting that ACS14 may stimulate antioxidants in the gastric tissue. ACS14 also obviously inhibited Asp-induced upregulation of protein expression of oxidases including XOD, p47(phox) and p67(phox). In conclusion, ACS14 protects Asp induced gastric mucosal injury by inhibiting oxidative stress in the gastric tissue.

Pharmacokinetics and relative bioavailability of a fixed-dose combination of enteric-coated naproxen and non-enteric-coated esomeprazole magnesium

This randomized, 4-way crossover study assessed the single-dose pharmacokinetics and relative bioavailability of naproxen and esomeprazole after administration of a fixed-dose combination tablet of enteric-coated (EC) naproxen 500 mg and non-EC esomeprazole magnesium 20 mg (NAP/ESO tablet). Equivalent doses of an EC naproxen tablet plus an EC esomeprazole magnesium capsule taken concomitantly, an EC naproxen tablet alone, or an EC esomeprazole magnesium capsule alone were used as comparators. Forty healthy adults were randomized to receive 4 study treatments with a washout interval ≥12 days. Naproxen plasma profiles were similar between the NAP/ESO tablet and EC naproxen, although median t(max) was longest for the NAP/ESO tablet (5.3 vs 3.5-4.0 hours). Naproxen C(max), AUC(0-∞), and AUC(0-t) showed bioequivalence between naproxen formulations. The NAP/ESO tablet produced much shorter esomeprazole t(max) than the EC esomeprazole formulation (0.45 vs 2.5 hours). Esomeprazole C(max) and AUCs were comparable between the EC esomeprazole formulation administered with or without EC naproxen but were lower with the NAP/ESO tablet. In conclusion, there are no pharmacokinetic drug interactions between naproxen and esomeprazole. The NAP/ESO tablet is bioequivalent to EC naproxen, and as expected, the bioavailability of non-EC esomeprazole from the NAP/ESO tablet is lower than the EC esomeprazole formulation.

Advances in the clinical applications of esomeprazole

Esomeprazole is the first proton pump inhibitor (PPI) to be developed as a single optical isomer. Ever since its first clinical application seven years ago, esomeprazole has attracted more and more attention due to relatively unique metabolism (compared to other PPIs), efficient and durable acid control, better safety and lower incidence of adverse reactions. In this article, we will review the clinical applications of esomeprazole in the treatment of gastroesophageal reflux disease (GERD), Helicobacter pylori infection, peptic ulcers, NSAID-related gastrointestinal disorders and upper gastrointestinal bleeding.

Characterization of mechanisms underlying the effects of esomeprazole on the impairment of gastric ulcer healing with addition of NSAID treatment

BACKGROUND

The efficacy of proton pump inhibitors in patients at high risk of gastrointestinal injury receiving non-steroidal anti-inflammatory drugs is currently debated.

AIMS

To evaluate the effects of esomeprazole on the impairment of gastric ulcer healing associated with non-steroidal anti-inflammatory drug treatment.

METHODS

Gastric ulcers were induced in rats by acetic acid. Four days later, animals were treated daily with equivalent acid-inhibiting doses of esomeprazole or famotidine, alone or in combination with indomethacin. At day 3 or 7 of treatment, ulcerated tissues were processed to assess: ulcer area; malondialdehyde; prostaglandin E(2); nuclear factor-kB; proliferating cell nuclear antigen and caspase-3 (Western blot).

RESULTS

In indomethacin-treated animals, esomeprazole was more effective than famotidine or the antioxidant melatonin in promoting ulcer healing. Malondialdehyde levels were increased by indomethacin, and this effect was counteracted by esomeprazole, but not famotidine. Esomeprazole and famotidine, given alone or in combination with indomethacin, increased proliferating cell nuclear antigen expression. Increased levels of prostaglandin E(2) were detected in ulcerated tissues. Ulcer prostaglandin E(2) production was reduced by indomethacin, alone or in combination with esomeprazole or famotidine, while it was enhanced when esomeprazole or famotidine were tested alone. The activation of caspase-3 was induced by indomethacin, and this effect was prevented by esomeprazole, but not famotidine. In the presence of indomethacin, esomeprazole, but not famotidine, enhanced nuclear factor-kB activation in gastric ulcers.

CONCLUSIONS

Esomeprazole counteracts the detrimental action of indomethacin on ulcer repair through both acid-dependent and acid-independent effects. The acid-independent actions are related to decrease in tissue oxidation and apoptosis and to enhancement of nuclear factor-kB activation.

Role of coxibs in the strategies for gastrointestinal protection in patients requiring chronic non-steroidal anti-inflammatory therapy

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most commonly prescribed drugs due to their high efficacy in the treatment of pain, fever, inflammation and rheumatic disorders. However, their use is associated with the occurrence of adverse effects at the level of digestive tract, ranging from dyspeptic symptoms, gastrointestinal erosions and peptic ulcers to more serious complications, such as overt bleeding or perforation. To overcome problems related to NSAID-induced digestive toxicity, different therapeutic strategies can presently be considered, including the co-administration of drugs endowed with protective activity on the upper gastrointestinal tract, such as the proton pump inhibitors, or the prescription of coxibs, which have been clinically developed as anti-inflammatory/analgesic drugs characterized by reduced damaging activity on gastrointestinal mucosa. The availability of different treatment options, to reduce the risk of NSAID-induced adverse digestive effects, has fostered intensive preclinical and clinical research aimed at addressing a number of unresolved issues and to establish rational criteria for an appropriate use of coxibs in the medical practice. Particular attention is being paid to the management of patients with high degrees of digestive risk, resulting by concomitant treatment with low-dose aspirin for anti-thrombotic prophylaxis or ongoing symptomatic gastroduodenal ulcers. The present review discusses the most relevant lines of evidence concerning the position of coxibs in the therapeutic strategies for gastrointestinal protection in patients who require NSAID therapy and hold different levels of risk of developing adverse effects at the level of digestive tract.