The Protective Effect of Lercanidipine on Indomethacin-Induced Gastric Ulcers in Rats

Abstract Nonsteroidal anti-inflammatory drugs (NSAID) are among the aggressive factors causing gastric ulcer. They cause oxidative damage in the gastric tissue and lead to intracellular calcium deposition. Lercanidipine is a calcium channel blocker derived from the third generation dihydropyridine. The aim of this study is to analyse the effect of lercanidipine on indomethacin-induced gastric ulcers. A total of 24 albino Wistar male rats were divided into four groups; those who received indomethacin 25 mg/kg (IND), 5 mg mg/kg lercanidipine +25 mg/kg indomethacin (LC-5), 10 mg/kg lercanidipine+25mg/kg indomethacin (LC-10) and healthy rats who received 0.5 mL distilled water. Six hours after the application of indomethacin, the animals were sacrificed by high dose thiopental sodium. The stomachs of the animals were excised to perform a macroscopic analysis and the ulcerous region was measured on millimeter paper. All the stomachs were subjected to a biochemical analysis. Macroscopic analysis revealed hyperaemia on the gastric surface of the indomethacin group. Ulcerous tissues formed by oval, circular or irregular mucosal defects in varying diameters and depths were observed on the whole surface of the stomach. Hyperaemia was lower and ulcerous region was smaller in groups LC-5 and LC-10 compared to IND group. Malondialdehyde and myeloperoxidase levels were significantly lower and total glutathione and cyclooxygenase-1 activity were higher in groups LC-5 and LC-10. Lercanidipine did not change the cyclooxygenase-2 activity. Lercanidipine in doses 10 mg/kg is more effective compared to 5 mg/kg. Lercanidipinine can be useful in the treatment of NSAID-induced gastric damage.

Effect of ethyl acetate extract of usnea longissima on esophagogastric adenocarcinoma in rats

Abstract Purpose: To investigate the effects of the EtOAc extract of U. longissima which is uninvestigated previously on esophagogastric cancer induced in rats with N-methyl-N-nitro-N-nitrosoguanidin (MNNG). Methods: The anticancer activity of EtOAc extract of U. longissima was examined in the esophagogastric adenocarcinoma models induced in rats with MNNG. EtOAc extract of U. longissima, 50 and 100 mg/kg oral doses were administered once daily for six months. MNNG induced differentiated and undifferentiated type adenocarcinomas in the esophageal and gastric tissues of rats. Results: EtOAc extract of U. longissima obtained from U. longissima prevented gastric and esophageal cancerogenesis induced in rats with MNNG. EtOAc extract of U. longissima did not have a lethal effect at doses of 500, 1000 and 2000 mg/kg. The prominent anticarcinogenic activity of EtOAc extract of U. longissima 50 and 100 mg/kg suggests that it is not toxic and it is selective to the cancer tissue. Conclusion: This information may shed light on clinical implementation of EtOAc extract of U. longissima in future.

The effect of metyrosine on oxidative gastric damage induced by ischemia/reperfusion in rats. Biochemical and histopathological evaluation

Abstract Purpose: To investigate the effect of metyrosine against I/R induced gastric damage in rats. Methods: Eighteen albino Wistar male rats were divided into groups; gastric I/R (GIR), 50 mg/kg metyrosine+gastric I/R (MGIR), and sham (SG) groups. 50 mg/kg metyrosine was given to the MGIR group, and distilled water was given to the GIR and SG groups by the oral gavage. After 30 minutes, 25 mg/kg thiopental sodium was injected intraperitoneally. Ischemia was achieved for 1 hour by clamping the celiac artery of the MGIR and GIR groups, then reperfusion was achieved for 3 hours. After that, animals were killed with 50 mg/kg thiopental. Biochemical and histopathological examinations performed on the gastric tissues. Results: Metyrosine decreased the MDA and MPO and the increased the tGSH and SOD. In addition, it reduced inflammation by suppressing the decrease of COX-1 and the increase of COX-2. Histopathologically, metyrosine decreased symptoms caused by I/R such as mucosal necrosis, hemorrhage, edema, PMNL infiltration, and dilated congested blood vessels. Conclusions: Metyrosine prevented the I/R induced oxidative stress in the gastric tissue. Metyrosine may be beneficial for gastric I/R injury.

Effect of thiamine pyrophosphate on retinopathy induced by hyperglycemia in rats: A biochemical and pathological evaluation.

Purpose: Information is lacking on the protective effects of thiamine pyrophosphate (TPP) against hyperglycemia‑induced retinopathy in rats. This study investigated the biochemical and histopathological aspects of the effect of TPP on hyperglycemia‑induced retinopathy induced by alloxan in rats. Materials and Methods: The rats were separated into a diabetic TPP‑administered group (DTPG), a diabetes control group (DCG) and a healthy group (HG). While the DTPG was given TPP, the DCG and HG were administered distilled water as a solvent at the same concentrations. This procedure was repeated daily for 3 months. At the end of this period, all of the rats were euthanized under thiopental sodium anesthesia, and biochemical and histopathological analyses of the ocular retinal tissues were performed. The results of the DTPG were compared with those of the DCG and HG. Results: TPP prevented hyperglycemia by increasing the amount of malondialdehyde and decreasing endogen antioxidants, including total glutathione, glutathione reductase, glutathione S‑transferase and superoxide dismutase. In addition, the amounts of the DNA oxidation product 8‑hydroxyguanine were significantly lower in the retinas of the DTPG compared to the DCG. In the retinas of the DCG, there was a marked increase in vascular structures and congestion, in addition to edema. In contrast, little vascularization and edema were observed in the DTPG, and there was no congestion. The results suggest that TPP significantly reduced the degree of hyperglycemia‑induced retinopathy. Conclusions: The results of this study indicate that TPP may be useful for prophylaxis against diabetic retinopathy.

Can thiamine pyrophosphate prevent desflurane induced hepatotoxicity in rats?

ABSTRACT PURPOSE : To investigate the effects of thiamine pyrophosphate (TPP) against desflurane induced hepatotoxicity. METHODS : Thirty experimental animals were divided into groups as healthy (HG), desflurane control (DCG) , TPP and desflurane group (TDG). 20 mg/kg TPP was injected to intraperitoneally TDG. After one hour of TPP administration, desflurane was applied for two hours. After 24 hours, liver tissues of the animals killed with decapitation were removed. The oxidant/antioxidant levels and ALT, AST and LDH activities were measured. The histopathological examinations were performed in the liver tissues for all rats. RESULTS : Notwithstanding the levels of oxidants and liver enzymes were significantly increased (p<0.0001), antioxidant levels were significantly decreased in DCG (p<0.0001). On contrary to the antioxidant parameters were increased (p<0.05) the oxidant parameters and liver enzymes were decreased in TDG (p<0.0001). Whereas multiple prominent, congestion, hemorrhage and dilatation were observed in sinusoids and lymphocyte-rich inflammation results in the centrilobular and portal areas of liver tissue in DCG, these findings were observed less frequently in TDG. CONCLUSİON : Thiamine pyrophosphate prevented liver oxidative damage induced with desflurane and may be useful in prophylaxis of desflurane induced hepatotoxicity.