Inhibitory effect of fluvastatin on ileal ulcer formation in rats induced by nonsteroidal antiinflammatory drug

AIM: Nonsteroidal anti-inflammatory drugs (NSAIDs)cause gastrointestinal damage as one of their side effects in humans and experimental animals. Lipid peroxidation plays an important role in NSAID-induced ulceration. The aim of this study was to investigate the inhibitory effect of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA)reductase inhibitors on the ulceration in small intestines of rats.METHODS: The effects of three HMG-CoA reductase inhibitors, fluvastatin, pravastatin and atorvastatin on ileal ulcer formation in 5-bromo-2-(4-fluorophenyl)-3-(4-methylsulfonylphenyl) thiophene (BFMeT)-treated rats were examined. Antioxidative activity of the inhibitors was measured by a redox-linked colorimetric method.RESULTS: Fluvastatin, which was reported to have antioxidative activity, repressed the ileal ulcer formation in rats treated with BFMeT an NSAIDs. However, the other HMG-CoA reductase inhibitors (pravastatin and atorvastatin)did not repress the ileal ulcer formation. Among these HMG-CoA reductase inhibitors, fluvastatin showed a significantly stronger reducing power than the others(pravastatin, atorvastatin).CONCLUSION: Fluvastatin having the antioxidaitive activity suppresses ulcer formation in rats induced by NSAIDs.

Nonsteroidal anti-inflammatory drugs before endoscopic ultrasound guided tissue acquisition to reduce the incidence of post procedural pancreatitis

Endoscopic ultrasound(EUS)with fine needle aspiration or fine needle biopsy is the gold standard for sampling tissue to diagnose pancreatic cancer and auto-immune pancreatitis or to analyze cyst fluid.The most common reported adverse event of fine needle aspiration and/or fine needle biopsy is acute pancreatitis,which is likely induced by the same pathophysiological mechanisms as after en-doscopic retrograde cholangiopancreatography(ERCP).According to the current European Society of Gastrointestinal Endoscopy guideline,nonsteroidal anti-inflammatory drugs are administered prior to ERCP as a scientifically proven treatment to reduce post-ERCP pancreatitis incidence rate.A single suppository of diclofenac or indomethacin prior to EUS guided tissue acquisition(TA)is harm-less in healthy adults.Since it is associated with low costs and,most important,may prevent a dreadsome complication,we strongly recommend the adminis-tration of 100 mg diclofenac rectally prior to EUS-TA.We will explain this recom-mendation in more detail in this review as well as the risk and pathophysiology of post-EUS TA pancreatitis.

Triggers of histologically suspected drug-induced colitis

BACKGROUND Drug toxicity is a common and even serious problem in the gastrointestinal tract that is thought to be caused by a broad spectrum of agents.Although withdrawal of the causative agent would cure the disease knowledge is scarce and mostly derives from case reports and series.AIM To investigate potential triggers of drug-induced colitis(DiC).METHODS We conducted a retrospective,observational case control study.Patients were assigned to DiC or one of two age-and gender-matched control groups(noninflammatory controls and inflammatory colitis of another cause)based on histopathological findings.Histopathology was reassessed in a subset of patients(28 DiC with atherosclerosis,DiC without atherosclerosis and ischaemic colitis each)for validation purposes.Medical history was collected from the electronic database and patient records.Statistical analysis included chi-squared test,t-test,logistic and multivariate regression models.RESULTS Drug-induced colitis was detected in 211 endoscopically sampled biopsy specimens of the colon mucosa(7%of all screened colonoscopic biopsy samples);a total of 633 patients were included equally matched throughout the three groups(291 males,mean age:62.1±16.1 years).In the univariate analysis,DiC was associated with diuretics,dihydropyridines,glycosides,ASS,platelet aggregation inhibitors,nonsteroidal anti-inflammatory drugs(NSAIDs),statins and fibrates,and with atherosclerosis,particularly coronary heart disease,and hyperlipoproteinaemia.Echocardiographic parameters did not show substantial differences.In the multivariate analysis only fibrates[odds ratio(OR)=9.1],NSAIDs(OR=6.7)and atherosclerosis(OR=2.1)proved to be associated with DiC.Both DiC reassessment groups presented milder inflammation than ischaemic colitis.The DiC patients with atherosclerosis exhibited histological features from both DiC without atherosclerosis and ischaemic colitis.CONCLUSION Several drugs indicated for the treatment of cardiovascular and related diseases are associated with DiC.Atherosclerosis and microcirculatory disturbances seem to play an important pathogenetic role.

Split-dose or hybrid nonsteroidal anti-inflammatory drugs and Nacetylcysteine therapy for prevention of post-retrograde cholangiopancreatography pancreatitis

BACKGROUND Despite significant technical and training improvements, the incidence of postendoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP) has not significantly dropped. Although many studies have evaluated the efficacy of various agents, e.g. nonsteroidal anti-inflammatory drugs, octreotide,antioxidants, administered via various dosages, routes(oral, intrarectal or parenteral), and schedules(before or after the procedure), the results have been conflicting.AIM To evaluate efficacy of three pharmacologic prophylactic methods for prevention of PEP.METHODS In this prospective, single-center randomized trial, patients who underwent firsttime ERCP for choledocholithiasis were randomly assigned to three groups. The first group received 600 mg N-acetylcysteine 15 min prior to ERCP, and perrectum administration of 50 mg indomethacin both prior to and after completion of the ERCP. The second group was administered only the 50 mg indomethacin per-rectum both prior to and after the ERCP. The third group was administeredper-rectum 100 mg indomethacin only after the ERCP, representing the control group given the guideline-recommended regimen. The primary end-point was PEP prevention.RESULTS Among the total 211 patients evaluated during the study, 186 fulfilled the inclusion criteria and completed the protocol. The percentages of patients who developed PEP in each of the three groups were not significantly different(χ2 =2.793, P = 0.247). Among the acute PEP cases, for all groups, 14 patients developed mild pancreatitis(77.77%) and 4 moderate. No severe cases of PEP occurred, and in all PEP cases the resolution was favorable. No adverse events related to the medications(digestive hemorrhage, rectal irritation, or allergies)occurred.CONCLUSION The efficacies of split-dose indomethacin and combined administration(Nacetylcysteine with indomethacin) for preventing PEP were similar to that of the standard regimen.

Cyclooxygenases in hepatocellular carcinoma

Many epidemiological studies demonstrate that treatment with non-steroidal anti-inflammatory drugs （NSAIDs） reduce the incidence and mortality of certain malignancies, especially gastrointestinal cancer. The cyclooxygenase （COX） enzymes are well-known targets of NSAIDs. However, conventional NSAIDs nonselectively inhibit both the constitutive form COX-1, and the inducible form COX-2. Recent evidence indicates that COX-2 is an important molecular target for anticancer therapies. Its expression is undetectable in most normal tissues, and is highly induced by proinflammatory cytokines, mitogens, tumor promoters and growth factors. It is now well-established that COX-2 is chronically overexpressed in many premalignant, malignant, and metastastic cancers, including hepatocellular carcinoma （HCC）. Overexpression of COX-2 in patients with HCC is generally higher in welldifferentiated HCCs compared with less-differentiated HCCs or histologically normal liver, suggesting that COX-2 may be involved in the early stages of hepatocarcinogenesis, and increased expression of COX-2 in noncancerous liver tissue has been significantly associated with shorter disease-free survival in patients with HCC. In tumors, overexpression of COX-2 leads to an increase in prostaglandin （PG） levels, which affect many mechanisms involved in carcinogenesis, such as angiogenesis, inhibition of apoptosis, stimulation of cell growth as well as the invasiveness and metastatic potential of tumor cells. The availability of novel agents that selectively inhibit COX-2 （COXIB）, has contributed to shedding light on the role of this molecule. Experimental studies on animal models of liver cancer have shown that NSAIDs, including both selective and non-selective COX-2 inhibitors, exert chemopreventive as well as therapeutic effects. However, the key mechanism by which COX-2 inhibitors affect HCC cell growth is as yet not fully understood. Increasing evidence suggests the involvement of molecular targets other than COX-2 in the antiproliferative effects of COX-2 selective inhibitors. Therefore, COX-inhibitors may use both COX-2- dependent and COX-2-independent mechanisms to mediate their antitumor properties, although their relative contributions toward the in vivo effects remain less clear. Here we review the features of COX enzymes, the role of the expression of COX isoforms in hepatocarcinogenesis and the mechanisms by which they may contribute to HCC growth, the pharmacological properties of COX-2 selective inhibitors, the antitumor effects of COX inhibitors, and the rationale and feasibility of COX-2 inhibitors for the treatment of HCC.

Efficacy of intramuscular diclofenac and fluid replacement in prevention of post-ERCP pancreatitis

AIM： TO assess the efficacy of intramuscular diclofenac and fluid replacement for prevention of post-endoscopic retrograde cholangiopancreatography （ERCP） pancreatitis.METHODS： A prospective, placebo-controlled study was conducted in 80 patients who underwent ERCP. Patients were randomized to receive parenteral diclofenac at a loading dose of 75 mg followed by the infusion of 5-10 mL/kg per hour isotonic saline over 4 h after the procedure, or the infusion of 500 mL isotonic saline as placebo. Patients were evaluated clinically, and serum amylase levels were measured 4, 8 and 24 h after the procedure.RESULTS： The two groups were matched for age, sex, underlying disease, ERCP findings, and type of treatment. The overall incidence of pancreatitis was 7.5% in the diclofenac group and 17.5% in the placebo group （12.5% in total）. There were no significant differences in the incidence of pancreatitis and other variables between the two groups. In the subgroup analysis, the frequency of pancreatitis in the patients without sphincter of Oddi dysfunction （SOD） was significantly lower in the diclofenac group than in the control group （ρ = 0.047）.CONCLUSION： Intramuscular diclofenac and fluid replacement lowered the rate of pancreatitis in patients without SOD.

Ketoprofen,peginterferon 2a and ribavirin for genotype 1 chronic hepatitis C:A phaseⅡ study

AIM:To evaluate the safety of adding ketoprofen to pegylated-interferon(PEG-IFN)with or without ribavirin and the effect on viral kinetics,STAT1 activity and expression of 2'-5'-oligoadenylate synthetase (2'-5'OAS)in genotype 1 chronic hepatitis C in a phaseⅡstudy. METHODS:Forty-five patients were studied:fifteen were randomized to PEG-IFN plus ribavirin(PR),16 to PEGIFN plus ketoprofen and 14 to PR and ketoprofen.Themolecular study of IFN-dependent signal transduction was conducted in 9 patients from each group. RESULTS:The combination of ketoprofen and PEG- IFN with or without ribavirin was safe and well tolerated.An early activation of STAT1 was observed in ke-toprofen-treated patients,but this activation was less sustained over time.Conversely,ketoprofen plus PEG- IFN and ribavirin induced an early and sustained increase of 2'-5'OAS transcription starting 24 h after the first dose until the 36th wk.These data are consistent with the clinical results,showing a better sustained virological response and a lower relapse rate in patients receiving ketoprofen plus PEG-IFN and ribavirin. CONCLUSION:The addition of ketoprofen to the standard therapy of chronic hepatitis C should be explored in larger randomized clinical studies.

Expert consensus of Chinese Association for the Study of Pain on the non-opioid analgesics for chronic musculoskeletal pain

Chronic musculoskeletal pain(CMP)is a common occurrence in clinical practice and there are a variety of options for the treatment of it.However,the pharmacological therapy is still considered to be a primary treatment.The recent years have witnessed the emergence of opioid crisis,yet there are no relevant guidelines on how to treat CMP with non-opioid analgesics properly.The Chinese Medical Association for the Study of Pain convened a panel meeting to develop clinical practice consensus for the treatment of CMP with non-opioid analgesics.The purpose of this consensus is to present the application of nonsteroidal antiinflammatory drugs,serotonin norepinephrine reuptake inhibitors,serotonin and norepinephrine reuptake inhibitors,muscle relaxants,ion channel drugs and topical drugs in CMP.

A tribute to Dr.Frank I Tovey on his 90th birthday

This paper pays a tribute to Dr.Frank I Tovey on his 90th birthday which happens on September 1,2011,and briefly describes the major findings in his research career and contributions as follows.The geographical prevalence of duodenal ulceration is related to staple diets.Unrefined wheat and maize,soya,certain pulses and millets are associated with a low prevalence while refined wheat,maize and rice,yams,cassava and green banana with a high prevalence.Predominant foodstuffs from low prevalence areas are ulceroprotective in rat peptic ulcer models.The protective activity lies in the lipid fraction present in these foodstuffs.The lipid fraction also promotes ulcer healing,is active both orally and intramuscularly and is ulceroprotective against nonsteroidal anti-inflammatory drugs(NSAIDs).The phospholipids and phytosterols present in the lipid have been identified to be responsible for this protective activity.The combination of phospholipids and phytosterols may be of value in the prevention and treatment of duodenal ulceration and protection against the ulcerogenic effect of NSAIDs.

Synthesis and Pharmacological Evaluation of Novel Conjugates of Indomethacin with Antioxidant Activity

A series of new conjugates of indomethacin with phenolic anfioxidants were synthesized for enhanced antiinflammatory activity as well as reduced ulcerogenic potency. It was found that all conjugates were very potent antioxidants in vitro. They could inhibit lipid peroxidafion significantly, while 11b-11e and 13b-13e could also interact with DPPH. However these conjugates showed little inhibition against croton oil induced mouse ear swelling.

Esophageal ulcer induced by ibuprofen tablets

To the editor: The Non-steroidal antiinflammatory drugs (NSAIDs) are one of the most widely prescribed drugs,commonly used for rheumatoid diseases and illnesses accompanied by pain.However,the use of NSAIDs is often limited by the gastrointestinal toxicity.The NSAIDs inhibit cyclooxygenase (COX),which is an enzyme in the prostaglandin synthetic pathway,thereby decreasing pain,fever,and inflammation.