Novel insight into Robert's cytoprotection: complex therapeutic effect of cytoprotective pentadecapeptide pentadecapeptide BPC 157 in rats with perforated stomach throughout modulation of nitric oxide-system. Comparison with L-arginine, ranitidine and pantoprazole therapy and L-NG-nitro-L-arginine methyl ester worsening

Surgically perforated stomach (since direct injury in rats until persisting defect and huge adhesions (day 1, day 7)) fairly represent an unresolved cytoprotection issue, and thereby, we focused resolving of the immediate triad, particular vascular failure (vessels 'disappear'/empty), prolonged bleeding, debilitated defect large widening. Agents (mg/kg) or saline (controls) were given at 1 min post-injury as an abdominal bath (10 ml/rat throughout 2 min). Within 1 - 15 min post-injury period, with cytoprotective BPC 157 (0.01 μg), the rapidly restored vessels 'run' (vessels filled/reappeared) toward the perforated defect, and there is less bleeding, and defect contraction; advanced perforated lesion healing (day 1) to complete healing (day 7), and less adhesions. With pantoprazole (10 mg), early (vessels (worsening), bleeding (prolongation), defect (attenuated widening)) effect means eventual lesions and adhesions severity as in controls. Ranitidine (10 mg) early effect (vessels (improvement), bleeding (less bleeding), defect (eliminated widening, defect not changed)) means final lesions attenuation, but not complete healing, less adhesions. L-NAME (5 mg) early (vessels worsening, less bleeding, attenuated defect widening) and final (lesions aggravation, more adhesions) effect, versus L-arginine (100 mg) early (vessels improvement, more bleeding, attenuated defect widening) and final (lesions attenuation, less adhesions) effect, combined few simultaneously occurring nitric oxide (NO)-system distinct processes. Finally, in the stomach tissue surrounding defect, increased malondialdehyde (MDA)- and decreased NO-values, BPC 157 reversed to the normal healthy values, and mRNA expression studies (Cox2, VEGFa, Nos1, Nos 2, Nos3, Nkap (NF-kappa-B-activating protein gene)), done at that very early post-perforation-time, indicate a way how BPC 157 may act beneficially in the perforated stomach lesion throughout NO- and prostaglandinds-system.

Cardiovascular effects in vitro of aqueous extract of wild strawberry (Fragaria vesca, L.) leaves

In contrast to the strawberry fruits, strawberry leaves as a source of bioactive compounds with potentially beneficial biological effects have been largely overlooked. In this study we examined direct, dose-dependent effects of wild strawberry (Fragaria vesca, L.) leaves aqueous extract, in two experimental models and animal species, the isolated guinea pig hearts and rat aortic rings. Vasodilatory potential of the wild strawberry leaves extract was compared with vasodilatory activity of aqueous extract of hawthorn (Crataegus oxycantha, L) leaves with flowers, which can be regarded as a reference plant extract with a marked vasodilatory activity. The extracts were analysed by their "phenolic fingerprints", total phenolic content and antioxidative capacity. Their vasodilatory activity was determined and compared in the isolated aortic rings from 24 rats that were exposed to the extracts doses of 0.06, 0.6, 6, and 60 mg/100ml. Both extracts induced similar, dose-dependent vasodilation. Maximal relaxation was 72.2+/-4.4% and 81.3+/-4.5%, induced by the strawberry and hawthorn extract, respectively. To determine vasodilatory mechanisms of the wild strawberry leaves extract, endothelium-denuded and intact rings exposed to nitric oxide (NO) synthase inhibitor L-NAME or cyclooxygenase inhibitor indomethacin were used. Removal of the endothelium prevented and exposure to L-NAME or indomethacin strongly diminished the vasodilatatory response to the extract. In the isolated hearts (n=12), the wild strawberry extract was applied at concentrations of 0.06, 0.18, 0.6, and 1.8 mg/100ml. Each dose was perfused for 3.5 min with 15 min of washout periods. Heart contractility, electrophysiological activity, coronary flow and oxygen consumption were continuously monitored. The extract did not significantly affect heart rate and contractility, main parameters of the cardiac action that determine oxygen demands, while coronary flow increased up to 45% over control value with a simultaneous decrease of oxygen extraction by 34%. The results indicate that the aqueous extract of wild strawberry leaves is a direct, endothelium-dependent vasodilator, action of which is mediated by NO and cyclooxygenase products and which potency is similar to that of the hawthorn aqueous extract.

Dose dependent effects of standardized nose-horned viper (Vipera ammodytes ammodytes) venom on parameters of cardiac function in isolated rat heart

Direct, dose dependent effects of the nose-horned vipers (Vipera ammodytes ammodytes) venom on various parameters of cardiac action in isolated rat hearts were examined. Biochemical (protein content, SDS polyacrylamide gel electrophoresis) and biological (minimum haemorrhagic and necrotizing dose and lethal dose (LD(50))) characterization of the venom was performed before testing. The hearts were infused with venom doses of 30, 90 and 150 microg/mL for 10 min followed by 30 min of wash out period. Left ventricular pressure, coronary flow, heart rate, atrioventricular conduction, myocardial oxygen consumption, incidence and duration of arrhythmias were measured and relative cardiac efficiency was calculated. Cardiac CPK, LDH, AST and troponin I were measured as biochemical markers of myocardial damage. The venom caused dose dependent electrophysiological instability and depression of contractility and coronary flow. Effects on the heart rate were biphasic; transient increase followed by significant slowing of the frequency. Relative cardiac efficiency decreased as oxygen consumption remained high relative to the heart rate-contractility product, indicating purposeless expenditure of oxygen and energy. Effects by the dose of 30 microg/mL were highly reversible while the dose of 90 mug/mL caused damages that were mostly irreversible. The dose of 150 mug/mL induced irreversible asystolic cardiac arrest.