The role of cyclooxygenase selective inhibitors in the gastrointestinal tract

Evaluation of gastric tolerability for long-term use of diclofenac and celecoxib in male albino rats and potential gastroprotective benefits of royal jelly: a randomized controlled trial

OBJECTIVES

Nonsteroidal anti-inflammatory drugs (NSAIDs) are used for pain and inflammation relief. Our study aimed to explore the ulcerogenic effect of long-term diclofenac and celecoxib administration on male albino stomachs, focusing on the possible gastroprotective effect of royal jelly (RJ) administration.

METHODS

Five equal groups of 50 male albino rats. The drug dosages were: diclofenac potassium (10 mg/kg/day), celecoxib (50 mg/kg/day), and RJ (300 mg/kg/day), for 4 weeks. Group 1 received no medication. Group 2 received oral diclofenac potassium. Group 3 received oral RJ plus diclofenac potassium. Group 4 received celecoxib orally. Group 4 received oral RJ plus celecoxib. When the experiment was over, rats were euthanized, blood samples were gathered, and stomachs were dissected out. Stomachs were examined for ulcer counts. Serum levels of MDA and SOD were determined. Gastric mucosa contents of MDA, SOD, PGE2, MPO, apoptotic (Bax), and anti-apoptotic (Bcl-2) genes were measured. Gastric tissue was also analyzed histopathologically.

RESULTS

Long-term administration of diclofenac and celecoxib, in such dose and duration, caused each of the aforementioned parameters to significantly deteriorate, with significant improvement with RJ co-administration. Diclofenac developed severe gastric ulcers in group 2, and RJ co-administration significantly reduced the gastric mucosa damage in group 3. Celecoxib developed no gastric ulcer in both groups 4 and 5.

CONCLUSIONS

Long-term use of diclofenac in male albino rats caused severe gastric ulcers with significant gastroprotective effects of RJ. Celecoxib provides preferable GI tolerability; thus, it should be prescribed for patients at increased risk of gastrointestinal bleeding requiring NSAIDs.

Nephro- and Cardiotoxic Effects of Etoricoxib: Insights into Arachidonic Acid Metabolism and Beta-Adrenergic Receptor Expression in Experimental Mice

Background: Etoricoxib is a widely used anti-inflammatory drug, but its safety profile concerning cardiovascular and renal health remains inadequately explored. This study aimed to assess the nephro- and cardiotoxic effects of etoricoxib in a murine model, with a focus on its impact on arachidonic acid-metabolizing enzymes and beta-adrenergic receptors associated with drug-induced toxicity. Methods: Thirty-five BALB/C mice were randomly assigned to five groups: control, low-dose etoricoxib, high-dose etoricoxib, low-dose celecoxib, and high-dose celecoxib (a well-known nephro- and cardiotoxic NSAID). The treatments were administered for 28 days, after which hearts and kidneys were excised for physical and histopathological analysis, and the expression of arachidonic acid-metabolizing enzymes (cytochrome P450s, lipoxygenases, cyclooxygenases) and beta-1 adrenergic receptor (adrb1) and angiotensin-converting enzyme (ace2) genes were quantified using quantitative reverse transcription PCR (qRT-PCR). Results: Etoricoxib administration resulted in dose-dependent nephro- and cardiotoxic effects. Renal histology revealed glomerular atrophy or hypertrophy and significant damage to the proximal and distal convoluted tubules, including epithelial flattening, cytoplasmic vacuolation, and luminal widening. Cardiac analysis showed disorganized muscle fibers and hyaline degeneration. These changes were associated with altered gene expression: the downregulation of cox2, cyp1a1, and cyp2c29 in the kidneys and the upregulation of cyp4a12, cox2, and adrb1, along with the downregulation of cyp2c29 and ace2 in the heart. Conclusions: Etoricoxib induces nephro- and cardiotoxicity, marked by alterations in arachidonic acid metabolism and beta-adrenergic signaling pathways. The drug affects the expression of arachidonic acid-metabolizing enzymes and adrb1 in the heart while downregulating cox2 and other related enzymes in the kidneys. These findings underscore the need for caution when prescribing etoricoxib, particularly in patients with pre-existing renal or cardiac conditions.

Cardioprotective role of royal jelly in the prevention of celecoxib-mediated cardiotoxicity in adult male albino rats

BACKGROUND

Celecoxib, a cyclooxygenase-2 selective inhibitor non-steroidal anti-inflammatory drugs, is used for the management of short- and long-term pain as well as in other inflammatory conditions. Unfortunately, its chronic use is highly associated with serious abnormal cardiovascular events. The current study was designed to explore the effect of long-term administration of celecoxib on the cardiac tissues of male albino rats. The study also examined the alleged cardioprotective effect of royal jelly.

METHODS

Thirty, male albino rats were randomly divided into 3 equal groups; 10 each: (1) rats served as the control group and received no drug; (2) rats received celecoxib (50 mg/kg/day, orally), for 30 consecutive days; (3) rats received celecoxib (50 mg/kg/day, orally) plus royal jelly (300 mg/kg/day, orally) for 30 consecutive days. Sera were collected to assay cardiac enzymes and oxidant/antioxidant status. Rats were euthanatized and cardiac tissues were dissected for quantitative estimation of apoptotic genes (Bax) and anti-apoptotic gene (Bcl-2).

RESULTS

Long-term celecoxib administration caused cardiotoxicity in male albino rats as manifested by significant elevation of serum levels of creatine phosphokinase (CPK), creatine kinase-MB (CK-MB), and lactate dehydrogenase (LDH), with ameliorative effects of royal jelly against celecoxib-induced cardiotoxicity as manifested by significantly decrease in serum CPK, CK-MB, and LDH levels. It also showed a significant decrease in the oxidative stress indicator malondialdehyde (MDA) levels and the bax gene. Additionally, it demonstrated significant increases in the bcl-2 gene and superoxide dismutase (SOD) levels, which contribute to its therapeutic effects against celecoxib-induced cardiotoxicity.

CONCLUSION

Long-term celecoxib administration caused cardiotoxicity in male albino rats with protective effect of royal jelly being given together. It could be concluded that royal jelly may prove a useful adjunct in patients being prescribed celecoxib.

TRIAL REGISTRATION

Not applicable.

Acetylsalicylic Acid Supplementation Affects the Neurochemical Phenotyping of Porcine Duodenal Neurons

Aspirin (ASA) is a popular nonsteroidal anti-inflammatory drug (NSAID), which exerts its therapeutic properties through the inhibition of cyclooxygenase (COX) isoform 2 (COX-2), while the inhibition of COX-1 by ASA results in the formation of gastrointestinal side effects. Due to the fact that the enteric nervous system (ENS) is involved in the regulation of digestive functions both in physiological and pathological states, the aim of this study was to determine the influence of ASA on the neurochemical profile of enteric neurons in the porcine duodenum. Our research, conducted using the double immunofluorescence technique, proved an increase in the expression of selected enteric neurotransmitters in the duodenum as a result of ASA treatment. The mechanisms of the visualized changes are not entirely clear but are probably related to the enteric adaptation to inflammatory conditions resulting from aspirin supplementation. A detailed understanding of the role of the ENS in the development of drug-induced inflammation will contribute to the establishment of new strategies for the treatment of NSAID-induced lesions.

Epidemiology and role of nonsteroidal antiinflammatory drugs in causing gastrointestinal bleeding

This article outlines the epidemiology and role of nonsteroidal antiinflammatory drugs (NSAIDs) in causing gastrointestinal (GI) bleeding. The morbidity and mortality associated with NSAID-induced GI bleeding are discussed, and the mechanisms of NSAID-related GI injury, the potency of various NSAIDs, new NSAIDs associated with a decrease in GI pathology, dual-acting antiinflammatory drugs, hydrogen sulfide-releasing NSAIDs, lipoxygenase/cyclooxygenase, phospholipid NSAIDs, and the comprehensive effects of NSAIDs on the GI tract are described.

Gastrointestinal bleeding

Gastrointestinal bleeding is a common complaint encountered in the emergency department and frequent cause of hospitalization. Important diagnostic factors that increase morbidity and mortality include advanced age, serious comorbid conditions, hemodynamic instability, esophageal varices, significant hematemesis or melena, and marked anemia. Because gastrointestinal bleeding carries a 10% overall mortality rate, emergency physicians must perform timely diagnosis, aggressive resuscitation, risk stratification, and early consultation for these patients.

Synthesis and pharmacological evaluation of novel 5-substituted-1-(phenylsulfonyl)-2-methylbenzimidazole derivatives as anti-inflammatory and analgesic agents

A series of novel 5-substituted-1-(phenylsulfonyl)-2-methylbenzimidazole derivatives have been synthesized. The structures of these compounds were established by IR, 1H NMR, 13C NMR, Mass spectral data and elemental analyses. Compounds were evaluated for their anti-inflammatory and analgesic activity as well as gastric ulcerogenic effects. Derivatives 4a, 4b and 4c exhibited moderate to good anti-inflammatory and analgesic activity in carrageenan-induced rat paw edema and acetic acid-induced writhing in mice, respectively, with low ulcerogenicity compared with the standard drug indomethacin.

Clinical trial: the incidence and early mortality after peptic ulcer perforation, and the use of low-dose aspirin and nonsteroidal anti-inflammatory drugs

BACKGROUND

It is not clear whether the incidence or early mortality related to peptic ulcer perforation has changed.

AIM

To evaluate the incidence and mortality related to peptic ulcer perforation while considering the intake of low-dose aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs).

METHODS

We recorded the numbers and details of all patients presenting in our region of Scotland with perforation between 1997 and 2006 including demography, drug usage and 30-day mortality.

RESULTS

In subjects aged >65 years, the annual incidence of perforation was 32.7 per 10(5) of the age-specific population, of whom 10.7 per 10(5) were taking low-dose aspirin and 12.0 taking NSAIDs. These were all significantly higher (P < 0.001) than the corresponding incidence in subjects aged < or =65 years (6.6 per 10(5) overall, 1.1 taking aspirin and 2.5 taking NSAIDs). There was an increasing trend with time in the number of patients taking NSAIDs (chi(2) = 4.57, P = 0.03). Using univariate analysis, 30-day mortality was associated with aspirin [odds ratio, 2.32 (95% C.I., 1.20-4.47), P = 0.01] but not with NSAIDs. The strongest predictors of mortality were increasing age and comorbidity.

CONCLUSIONS

Perforation remains common in elderly patients including users of NSAIDs and aspirin. Early mortality is also noted in association with increasing age and comorbidity, but not independently with drug intake.

Incidence of perforated diverticulitis and risk factors for death in a UK population

Background

Perforated diverticulitis (PD) remains a serious acute abdominal condition. The aims of this study were to measure its incidence in a large UK population and to identify factors affecting outcomes.

Methods

Computerized searches of hospital coding databases for PD were performed in five hospitals in East Anglia, UK. Data were collected from hospital records over 5 years (1995–2000). Incidence was calculated using population data, and factors associated with mortality and morbidity were identified using univariable and multivariable testing.

Results

Some 202 patients with PD were identified, of whom 93·1 per cent underwent surgery and 24·3 per cent died. The age-adjusted adult incidence of perforation was 3·5 per 100 000 per annum, with a standardized female to male ratio of 1·3 (95 per cent confidence interval (c.i.) 1·1 to 1·5) to 1. Risk factors for death were increased age (odds ratio (OR) 3·5 (95 per cent c.i. 1·9 to 6·1)), pre-existing renal disease (OR 18·7 (1·6 to 211·4)) and pre-existing use of non-steroidal anti-inflammatory drugs (NSAIDs) (OR 3·1 (1·3 to 7·3)).

Conclusion

PD is uncommon, with the highest incidence in women over 65 years old. Mortality rates are high, particularly in those taking NSAIDs or with pre-existing renal impairment.

Initial management of acute upper gastrointestinal bleeding: from initial evaluation up to gastrointestinal endoscopy

Acute upper gastrointestinal bleeding is a relatively common, potentially life-threatening medical emergency responsible for more than 300,000 hospital admissions and about 30,000 deaths per annum in America. The initial assessment focuses on bleeding activity, bleeding severity, hemodynamic compromise from the bleeding, and differentiating upper from lower gastrointestinal bleeding. The initial supportive therapy includes fluid resuscitation to reverse the hypovolemia, blood transfusions to replete the lost blood, respiratory support as necessary, and proton pump inhibitor therapy to stabilize mucosal blood clots and promote hemostasis. Esophagogastroduodenoscopy is the best test to determine the bleeding site and cause.

The role of cyclooxygenase in gastric mucosal protection

COX-1 and COX-2 are two cyclooxygenase enzymes responsible for prostanoid production. COX-2 is expressed in inflammatory cells and fibroblasts of the gastric mucosa, and through the production of various growth factors including hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF), plays a key role in the tissue repair process. Aspirin induces and acetylates COX-2 to produce 15-(R)-epi-lipoxinA4, an anti-inflammatory mediator thought to protect the gastric mucosa against aspirin-induced injury. Recently, three different PGE synthases have been identified, that convert COX-2 metabolites into PGE2. mPGE synthase (mPGES)-1 has been shown to be inducible, and to colocalize with COX-2 in fibroblasts and macrophages infiltrating the gastric ulcer bed. cPGES and mPGES-2 have been found expressed in normal gastric mucosa, with no change in expression levels seen in gastritis or gastric ulcer tissue. Finally, this review discusses the role of these enzymes in the pathophysiology of the gastric mucosa, as well as the biologcal significance of their inhibition.

Recent advances in equine abdominal surgery

Laparoscopy is a minimally invasive procedure that has applications as a diagnostic, therapeutic and prognostic technique. Specialized equipment is necessary to perform equine laparoscopy, and there is a large range of instruments, both disposable and non-disposable available. Laparoscopic procedures described include ovariectomy, cryptorchidectomy, adhesiolysis and herniorrhaphy. Laparoscopy can be performed in a standing or dorsally recumbent position, depending on surgeon preference, patient status and the procedure to be performed. Stapling equipment is frequently used in gastrointestinal surgery in horses. Advantages include decreased surgical time and a decrease in the risk of contamination. Stapling equipment is often used in creating anastomoses, both in the large and small intestines, as well as in vessel ligation. New surgical techniques intended to decrease adhesion formation include the use of carboxymethylcellulose and bioresorbable patches. Indwelling abdominal drains can be used for peritoneal lavage following surgery and also appear to decrease the risk of adhesion formation. Improvements in post-operative care, including the treatment of post-operative ileus and endotoxaemia can significantly improve the outcome of horses that have undergone surgery for abdominal disorders. Recommendations for the use of prokinetic agents in horses with ileus vary widely. Prokinetic agents include local anaesthetics, macrolide antimicrobials, cholinergic agonists and dopamine antagonists. Endotoxaemia is common in horses following surgery for gastrointestinal disorders. The antibiotic polymyxin B binds to the circulating endotoxin molecule, decreasing its half-life in the intra-vascular space and reducing associated inflammation. This drug appears to be an effective and affordable treatment option for horses with endotoxaemia. The use of specific cyclooxygenase inhibitors in veterinary medicine have been studied recently. Selective cyclooxygenase-2 inhibitors may provide comparable anti-inflammatory and analgesic properties to the non-selective non-steroidal anti-inflammatory drugs. These drugs appear to have similar clinical effectiveness and will hopefully minimize deleterious side effects. The optimal healing of ventral midline incisions in horses is related to many factors including appropriate suture patterns and bite size, in addition to appropriate post-operative exercise recommendations. Recent advances in surgical techniques and post-operative care should decrease the morbidity and mortality associated with abdominal surgery. This article provides an overview of some of these advances.

Effect of cyclo-oxygenase inhibitors on Helicobacter pylori susceptibility to metronidazole and clarithromycin

BACKGROUND

We previously reported that aspirin inhibited Helicobacter pylori growth and suppressed the mutagenic effect of metronidazole.

AIM

To determine the effects of a cyclo-oxygenase (COX)-2-specific inhibitor, SC-236, and a non-selective COX inhibitor, indometacin, on the growth, urease activity and antimicrobial susceptibility of H. pylori.

METHODS

Three H. pylori reference strains, and 18 clinical isolates were treated with SC-236 or indometacin for 24 and 48 h. Growth, urease activity and susceptibility to clarithromycin and metronidazole of the bacteria were assessed by viable colony counting, spectrophotometry and E-test respectively.

RESULTS

SC-236 and indometacin inhibited H. pylori growth in a dose-dependent manner with the lowest inhibitory concentrations of 0.03 and 0.1 mm, and the lethal concentrations of 0.09 and 0.3 mm, respectively. The numbers of CFU/mL in Brucella broth containing 0.09 mm SC-236 were 2 log lower at 24 h, and even 3 log lower at 48 h than that at 0 h (P = 0.035, compared with the vehicle control). Treatment of 0.3 mm indometacin reduced the number of CFU/mL by 1 log at 24 h compared with that at 0 h (P = 0.037 compared with the vehicle control). Helicobacter pylori urease activity began to decrease with 0.06 mm SC-236 at 24 h (P = 0.016), and 0.3 mm indometacin at 48 h (P = 0.025). MICs of metronidazole and clarithromycin against H. pylori were decreased significantly in the presence of 0.03 mm SC-236 or 0.1 mm indometacin (all P < 0.001).

CONCLUSION

Both SC-236 and indometacin suppressed the growth and urease activity of H. pylori in a dose-dependent manner, and increased its susceptibility to the antibiotics.