Effect of salinity on the toxicity of diclofenac, ibuprofen and naproxen toward cyanobacterium Synechocystis salina.

Aquatic species are continuously exposed to pharmaceuticals and changeable water conditions simultaneously, which can induce changes in the toxicity of pollutants. Cyanobacterium are an organism for which less ecotoxicological tests have been performed compared to green algae. In this study, we decided to check how selected non-steroidal anti-inflammatory drugs (NSAID) affect the grow of Synechocystis salina, picocyanobacterium isolated from the Baltic Sea, with salinity as potential modulator of toxicity. S. salina was exposed to diclofenac (DCF), ibuprofen (IBF) and naproxen (NPX) (nominal 100 mg L-1) in BG11 medium and sea salt supplemented BG11 medium (38 PSU) over 96 h in continuous light at 23 °C. No acute toxicity was found in both tested salinity levels. The comparable grow rate in exposed culture compared to control culture over 4 days indicate lack of stress for several generations which need to be overcome with substantial energy consumption. S. salina was found to be halotolerant and can be species for ecotoxicology test where salinity in an additional stressor. Furthermore, resistant of S. salina to target NSAIDs provide a competitive advantage over other phytoplankton species.

Epiisopiloturine hydrochloride, an imidazole alkaloid isolated from Pilocarpus microphyllus leaves, protects against naproxen-induced gastrointestinal damage in rats.

OBJECTIVE: This study aimed to investigate the protective effect of epiisopiloturine hydrochloride (EPI), an imidazole alkaloid, on NAP-induced gastrointestinal damage in rats. METHODS: Initially, rats were pretreated with 0.5% carboxymethylcellulose (vehicle) or EPI (3, 10 and 30mg/kg, p.o. or i.p., groups 3-5, respectively) twice daily, for 2days. After 1h, NAP (80mg/kg, p.o.) was given. The control group received only vehicle (group 1) or vehicle+naproxen (group 2). Rats were euthanized on 2nd day, 4h after NAP treatment. Stomachs lesions were measured. Samples were collected for histological evaluation and glutathione (GSH), malonyldialdehyde (MDA), myeloperoxidase (MPO), and cytokines levels. Moreover, gastric mucosal blood flow (GMBF) was evaluated. RESULTS: EPI pretreatment prevented NAP-induced macro and microscopic gastric damage with a maximal effect at 10mg/kg. Histological analysis revealed that EPI decreased scores of damage caused by NAP. EPI reduced MPO (3.4±0.3U/mg of gastric tissue) and inhibited changes in MDA (70.4±8.3mg/g of gastric tissue) and GSH (246.2±26.4mg/g of gastric tissue). NAP increased TNF-α levels, and this effect was reduced by EPI pretreatment. Furthermore, EPI increased GMBF by 15% compared with the control group. CONCLUSION: Our data show that EPI protects against NAP-induced gastric and intestinal damage by reducing pro-inflammatory cytokines, reducing oxidative stress, and increasing GMBF.

Modulation by aspirin and naproxen of nucleotide alterations and tumors in the lung of mice exposed to environmental cigarette smoke since birth.

Chemoprevention provides an important strategy for cancer control in passive smokers. Due to the crucial role played by smoke-related chronic inflammation in lung carcinogenesis, of special interest are extensively used pharmacological agents, such as nonsteroidal anti-inflammatory drugs (NSAIDs). We evaluated the ability of aspirin and naproxen, inhibitors of both cyclooxygenase-1 and cyclooxygenase -2, to modulate environmental cigarette smoke (ECS)-induced lung carcinogenesis in A/J mice of both genders. Based on a subchronic toxicity study in 180 postweaning mice, we used 1600 mg/kg diet aspirin and 320 mg/kg diet naproxen. In the tumor chemoprevention study, using 320 mice, exposure to ECS started soon after birth and administration of NSAIDs started after weaning. At 10 weeks of life, the NSAIDs did not affect the presence of occult blood in feces. As assessed in a subset of 40 mice, bulky DNA adducts and 8-hydroxy-2'-deoxyguanosine levels were considerably increased in ECS-exposed mice and, irrespective of gender, both NSAIDs remarkably inhibited these nucleotide alterations. After exposure for 4 months followed by 5 months in filtered air, ECS induced a significant increase in the yield of surface lung tumors, the 43.7% of which were adenomas and the 56.3% were adenocarcinomas. Oct-4 (octamer-binding transcription factor 4), a marker of cell stemness, was detected in some adenocarcinoma cells. The NAIDs attenuated the yield of lung tumors, but prevention of ECS-induced lung adenomas was statistically significant only in female mice treated with aspirin, which supports a role for estrogens in ECS-related lung carcinogenesis and highlights the antiestrogenic properties of NSAIDs.

¹H NMR-based metabolic profiling of naproxen-induced toxicity in rats.

The dose-dependent perturbations in urinary metabolite concentrations caused by naproxen toxicity were investigated using ¹H NMR spectroscopy coupled with multivariate statistical analysis. Histopathologic evaluation of naproxen-induced acute gastrointestinal damage in rats demonstrated a significant dose-dependent effect. Furthermore, principal component analysis (PCA) of ¹H NMR from rat urine revealed a dose-dependent metabolic shift between the vehicle-treated control rats and rats treated with low-dose (10 mg/kg body weight), moderate-dose (50 mg/kg), and high-dose (100 mg/kg) naproxen, coinciding with their gastric damage scores after naproxen administration. The resultant metabolic profiles demonstrate that the naproxen-induced gastric damage exhibited energy metabolism perturbations that elevated their urinary levels of citrate, cis-aconitate, creatine, and creatine phosphate. In addition, naproxen administration decreased choline level and increased betaine level, indicating that it depleted the main protective constituent of the gastric mucosa. Moreover, naproxen stimulated the decomposition of tryptophan into kynurenate, which inhibits fibroblast growth factor-1 and delays ulcer healing. These findings demonstrate that ¹H NMR-based urinary metabolic profiling can facilitate noninvasive and rapid diagnosis of drug side effects and is suitable for elucidating possible biological pathways perturbed by drug toxicity.

Naproxen-PC: a GI safe and highly effective anti-inflammatory.

UNLABELLED: We have been developing a family of phosphatidylcholine (PC)-associated NSAIDs, which appear to have improved GI safety and therapeutic efficacy in both rodent model systems and pilot clinical trials. As naproxen has been demonstrated to be associated with the lowest cardiovascular adverse events in comparison with both COX-2 selective inhibitors and conventional NSAIDs, we have been developing a Naproxen-PC formulation for evaluation in animal models and clinical trials. We have determined that an oil-based formulation of naproxen and triple strength soy lecithin provides excellent GI protection in both: 1) an acute NSAID-induced intestinal bleeding model in rats pretreated with L-NAME that are intragastrically administered a single dose of naproxen (at a dose of 50 mg/kg) vs the equivalent dose of Naproxen-PC; and 2) a more chronic model (at a naproxen dose of 25 mg/kg BID) in rats that have pre-existing hindpaw inflammation (induced with a intradermal injection of Complete Freund's Adjuvant/CFA). Both models demonstrate the superior GI safety of Naproxen-PC vs naproxen while this novel formulation had significant anti-inflammatory efficacy to reduce hindpaw edema and the generation of PGE(2) in the collected joint synovial fluid. CONCLUSION: Naproxen-PC appears to induce significantly less GI injury and bleeding in two rodent model systems while maintaining anti-inflammatory and COX-inhibitory activity.

Protective effect of astaxanthin on naproxen-induced gastric antral ulceration in rats.

Frequently used for humans as non-steroidal anti-inflammatory drug, naproxen has been known to induce ulcerative gastric lesion. The present study investigated the in vivo protective effect of astaxanthin isolated from Xanthophyllomyces dendrorhous against naproxen-induced gastric antral ulceration in rats. The oral administration of astaxanthin (1, 5, and 25 mg/kg of body weight) showed a significant protection against naproxen (80 mg/kg of body weight)-induced gastric antral ulcer and inhibited elevation of the lipid peroxide level in gastric mucosa. In addition, pretreatment of astaxanthin resulted in a significant increase in the activities of radical scavenging enzymes such as superoxide dismutase, catalase, and glutathione peroxidase. A histologic examination clearly proved that the acute gastric mucosal lesion induced by naproxen nearly disappeared after the pretreatment of astaxanthin. These results suggest that astaxanthin removes the lipid peroxides and free radicals induced by naproxen, and it may offer potential remedy of gastric ulceration.

[Effects of drugs on cultured cells (III)].

Toxicity of drugs cultured cell line (RK12-, EL-cell line) were exposed to various concentrations/ml medium for 48 hours and for 14 days. The morphologic changes of both cell lines observed included granulation and shrinkage of the cytoplasm, formation of long and narrow cytoplasmic projection, and appearance of giant like cells. ID50 values of ibuprofen, naproxen, Y-5544, diclofenac and aminopyrine to RK13 cell were found to be 130, 290, 200, 140 and greater than 500 mug/ml respectively. On the other hand, ID50 values of each drug to FL-cell were found to be 105, greater than 500, 180, 170 and less than 500 mug/ml respectively. Minimum concentration, cuased by the detachment of the cell from the vessel wall, was as follows: to RK13 were ibuprofen 125 approximately 250, paproxen 250 approximately 500, Y-5554 125 approximately 250, diclofenac 62.5 approximately 125, aminopyrine 1000 approximately 2000 each mug/ml. On the other hand, to FL-cell were ibuprofen 62.5 approximately 125, naproxen 125 approximately 250, Y-5554 62.5 approximately 125, DIClofenac 62.5 approximately and aminopyrine 1000 approximately 2000 each mug/ml respectively.

[Effects of drugs on cell culture (I)].

Effects of drugs were studied on L-cell line: L, of mouse subcutaneous tissue origin. Results are as follows: the concentrations of 62.50 approximately 500 mug/ml for each drug were examined regarding inhibition of the growth of L-cell line. ID50 values of ibuprofen, naproxen, Y-5554, DICHLOFENAC AND AMINOPYRINE WERE FOUND TO BE 185, 185, 175, 145 AND GREATER THAN 500 MUG/ML RESPECTIVELY. Minimum concentration, caused by the detachment of the cell from the vessel wall, was as follows: ibuprofen 125 approximately 250, naproxen 250 approximately 500, Y-5554 125 approximately 250, dichlofenac 62.50 and aminopyrine 1,000 approximately 2,000 mug/ml respectively.

[Effects of drugs on cell culture (II)].

The toxicity of drugs was determined using embryonic skin and muscle from humans (Flow 1,000). The dosage causing a 50% inhibition culture growth (ID50) and minimum concentration, caused by the detachment of the cell from the vessel wall, were determined. ID50 values of ibuprofen, naproxen, Y-5554, dichlofenac and aminopyrine were found to be 150, 320,220, 110 and greater 500 mug/ml respectively. Minimum concentration, caused by the detachment of the from the vessel wall, was as follows: ibuprofen 250, naproxen 250-500, Y-5554 250-500, dichlofenac 62.50-125 and aminopyrine 1,000-2,000 mug/ml respectively.