Water Extract of Mentha x villosa: Phenolic Fingerprint and Effect on Ischemia-Reperfusion Injury.

Qualitative analysis of the water extract of Mentha x villosa Huds. leaves was performed by liquid chromatography mass spectrometry (LC-MS/MS) and quantitative analysis was made by reverse-phase liquid chromatography coupled with photodiode array detection (LC-DAD). Sixteen phenolic compounds were identified and quantified consisting of 8 phenolic acids/derivatives and 8 flavonoid glycosides (quinic acid, chlorogenic acid, coumaroyl-hexoside, caffeic acid, coumaroylquinic acid, lithospermic acid, rosmarinic acid, salvianolic acid A, luteolin-7-O-glucuronide, luteolin-7-O-glucoside, luteolin-7-O-rutinoside, eriodictyol-7-O-rutinoside, apigenin-7-O-glucuronide, kaempferol-3-O-glucuronide, chrysoeriol-7-O-rutinoside, and hesperetin-7-O-rutinoside).

Efficacy of quercetin derivatives in prevention of ulcerative colitis in rats.

Reactive oxygen species has been implicated to contribute significantly to tissue injury associated with ulcerative colitis. Thus compounds with antioxidant properties could be potential therapeutic agents in this disease. Flavonoid compounds are known to possess antioxidative and antiinflammatory properties.

Protection of the vascular endothelium in experimental situations.

One of the factors proposed as mediators of vascular dysfunction observed in diabetes is the increased generation of reactive oxygen species (ROS). This provides support for the use of antioxidants as early and appropriate pharmacological intervention in the development of late diabetic complications. In streptozotocin (STZ)-induced diabetes in rats we observed endothelial dysfuction manifested by reduced endothelium-dependent response to acetylcholine of the superior mesenteric artery (SMA) and aorta, as well as by increased endothelaemia.

Chemiluminescence response induced by mesenteric ischaemia/reperfusion: effect of antioxidative compounds ex vivo.

Ischaemia and reperfusion (I/R) play an important role in human pathophysiology as they occur in many clinical conditions and are associated with high morbidity and mortality. Interruption of blood supply rapidly damages metabolically active tissues. Restoration of blood flow after a period of ischaemia may further worsen cell injury due to an increased formation of free radicals.

Assessment of ischemic vascular damage.

This protocol describes a model convenient for acute experiments in anesthetized rats, performed by selective occlusion of the superior mesenteric artery. Such a model provides a means for assessing the role played by various pathophysiological mechanisms in the development of intestinal ischemic injury. It is especially suitable for studying different treatments, mainly pharmacological ones, to help cope with this problem in clinical practice.

Protective effect of melatonin in acetic acid induced colitis in rats.

Possible protective effects of exogenous melatonin on colonic inflammation were studied in rats. Colitis was induced by intracolonic (i.c.

Mesenteric ischemia/reperfusion-induced intestinal and vascular damage: effect of stobadine.

This study examined the effects of the pyridoindole compound stobadine on intestinal and vascular injury following mesenteric ischemia/reperfusion (I/R) in rats. Ischemia was induced by occlusion of the superior mesenteric artery (SMA) for 60 min, followed by 30 min reperfusion. To characterize gut impairment, some parameters of intestinal damage and biochemical variables, such as GSH content, activity of a lysosomal enzyme N-acetyl-beta-D-glucuronidase and activity of gamma-glutamyl transpeptidase, were determined.

Changes in the function and ultrastructure of vessels in the rat model of multiple low dose streptozotocin-induced diabetes.

In this study we investigated functional changes in the femoral artery and ultrastructural alterations in mesenteric vessels and capillaries in the rat model of multiple low dose streptozotocin (STZ)-induced diabetes. Participation of oxidative stress in this model of diabetes was established by studying the effect of the pyridoindole antioxidant stobadine (STB) on diabetes-induced impairment. Experimental diabetes was induced by i.

Participation of reactive oxygen species in diabetes-induced endothelial dysfunction.

Objectives: In the present study, the relationship between diabetes-induced hyperglycemia, reactive oxygen species production and endothelium-mediated arterial function was examined. The effect of antioxidant on the reactive oxygen species induced damage was tested.

Methods: Diabetes was induced by streptozotocin (STZ), 3 x 30 mg/kg i.

Ischaemia/reperfusion-induced organ injury in low dose streptozotocin diabetes.

Objectives: The influence of low dose streptozotocin diabetes on intestinal and vascular injury induced by mesenteric ischaemia/reperfusion (I/R) was studied in rats. The role of reactive oxygen species (ROS) in the exacerbation of ischaemic/postischaemic damage in diabetes was addressed.

Methods: Diabetes was induced by i.

Gut and vessel alterations induced by mesenteric ischaemia/reperfusion in rats.

A rat model of transient occlusion of the superior mesenteric artery was used to study the intestinal and vascular injury induced by ischaemia/ reperfusion (I/R). A pronounced intestinal injury was observed, ranging from hyperaemia to severe haemorrhagic necrosis and bleeding. The length of the damaged intestinal segments reached 58.

Contribution to safe anti-inflammatory therapy with indomethacin.

Non-steroidal anti-inflammatory drugs possess not only therapeutic but also adverse effects, mainly on the gastrointestinal tract. The aim of this pilot study was to establish the ulcerogenic dose caused by daily administration of indomethacin to male Lewis rats. Further, the model of rat adjuvant arthritis (AA) was used to evaluate the protective effect of stobadine dipalmitate against indomethacin-induced gastroenteropathy.

Differences between gastric antiulcer effects of trapencaine enantiomers.

The spatial arrangement of single stereoisomers may influence pharmacodynamic, pharmacokinetic and toxicological properties of a drug. Trapencaine (I. N.

Effects of pleuran (beta-glucan isolated from Pleurotus ostreatus) on experimental colitis in rats.

The effects of pleuran, beta-1,3 glucan isolated from Pleurotus ostreatus, were studied in a model of acute colitis induced by intracolonic administration of acetic acid. There was a reduction of the colonic damage score, colonic wet weight and wet/dry weight ratio 48 h after single luminal 2% pleuran suspension pretreatment. Similar results were obtained after repeated intraperitoneal administration of pleuran in doses of 30 and 100 mg/kg.

Effect of pleuran (beta-glucan from Pleurotus ostreatus) in diet or drinking fluid on colitis in rats.

The effects of pleuran, beta-glucan isolated from Pleurotus ostreatus, were studied in a model of acute colitis in rats. Pleuran was given either as a 2% food component or as 0.44% pleuran hydrogel drink over 4 weeks.

Effect of N-acetylcysteine on colitis induced by acetic acid in rats.

(1) To verify the proposed role of reactive oxygen species (ROS) in ulcerative colitis, the effect of an antioxidant N-acetylcysteine (NAC) was studied in acetic acid (AA)-induced colonic inflammation. (2) Depending on the dose used, NAC administered intracolonically was found to reduce the extent of colonic damage, along with a decrease in myeloperoxidase (MPO) activity, colonic wet weight and wet/dry weight ratio. (3) NAC attenuated the enhanced vascular permeability and prevented the depletion of colonic reduced glutathione (GSH) caused by AA administration.

Streptozotocin diabetes-induced changes in aorta, peripheral nerves and stomach of Wistar rats.

In rats with diabetes induced by streptozotocin (STZ), we studied the reactivity of the aorta in response to vasoconstrictor and vasorelaxant agents, changes in conduction velocity in the sciatic nerve, and glutathion (GSH) content in the gastric mucosa as well as the occurrence of spontaneous gastric lesions. STZ-induced diabetes was found to be accompanied by endothelial injury, exhibited by diminished endothelium-dependent relaxation and by increased noradrenaline- and H2O2-induced contraction. Conduction velocity in the nerves from STZ-treated animals was significantly lower compared to that in nerves from control animals.

Protective effect of stobadine in experimental colitis.

To assess the possible role of reactive oxygen species in inflammatory bowel disease, the effect of the antioxidant and free radical scavenger stobadine was studied in acetic acid-induced experimental colitis. Stobadine administered locally into the colon was found to reduce the extent of colonic mucosal injury, abolish the increase in myeloperoxidase activity, attenuate the enhanced vascular permeability, and prevent the depletion of reduced glutathione. The attempt to reduce pharmacologically excessive free radical production and oxidative damage in the inflamed colonic mucosa may be regarded as a complementary treatment of ulcerative colitis.

Effects of histamine H1 antagonist dithiaden on acetic acid-induced colitis in rats.

To assess the possible involvement of mast cells and/or their mediators in inflammatory bowel diseases, the effect of the histamine H1 antagonist Dithiaden was studied on a model of acetic acid-induced colitis in rats. Dithiaden pretreatment by intracolonic administration was found to reduce the extent of acute inflammatory colonic injury. This was manifested by a decrease in the score of gross mucosal injury, by lowered colonic wet weight and by diminished myeloperoxidase activity reflecting reduced leukocyte infiltration.

Gastric transmucosal potential difference: effect of antisecretory and gastroprotective drugs.

1. Ion transport and electrical resistance of the gastric mucosa are responsible for the generation of the transmucosal potential difference (PD), which is considered an index of mucosal integrity. 2.