The anxiolytic activity of n-3 PUFAs enriched egg yolk phospholipids in rat behavioral studies.

Phospholipids play an important role in the biochemical and physiological processes of cells. An association between disturbed phospholipids metabolism in neuronal tissue and anxiety it was shown. The aim of this study was to examine the anxiolytic properties of phospholipids obtained from a new generation of eggs enriched in n-3 PUFA and its effect on locomotor activity in rat behavioral studies N-3 PUFA-enriched egg yolk phospholipids ("super lecithin") were added to the standard feed. Rats were fed by chow without (control group) or with (experimental group) addition of phospholipids. After six weeks of supplementation, the effect of phospholipids on locomotor activity in the open field test and anxiolytic properties in elevated plus maze and Vogel conflict test were examined. In the open field test the total distance traveled in the experimental group was similar to the control group. In the elevated plus maze test a six weeks phospholipids' administration significantly prolonged the time spent on the open arms by rats from experimental group compared to control group. The number of entries into the open arms was also increased but the difference was not statistically significant. The number of punished drinking water in the Vogel conflict test increased significantly in experimental versus control group. The obtained results suggest that the phospholipids isolated from n-3 PUFA enriched egg yolk have a specific anxiolytic effect, without general sedative influence.

Effects of supplementation with fish oil and n-3 PUFAs enriched egg yolk phospholipids on anhedonic-like response and body weight in the rat chronic mild stress model of depression.

Polyunsaturated fatty acids play an important role in the human organism. They guarantee a normal function of nervous cells, influence neurotransmission, and build some elements of cellular membranes. Several reports indicate an association between a deficiency of polyunsaturated fatty acids and depression. The aim of this study was to examine the effects of diet supplemented with fish oil, which is rich in omega-3 polyunsaturated fatty acids (n-3 PUFAs) and n-3 PUFAs enriched phospholipids ("super lecithin") obtained from designed eggs on anhedonic-like response and body weight in the rat chronic mild stress (CMS) model of depression. The results showed that neither fish oil nor n-3 PUFAs enriched egg yolk phospholipids supplementation reversed disturbances caused by CMS, such as anhedonic-like state or reduction of body weight gain.

Effect of selected drugs on plasma asymmetric dimethylarginine (ADMA) levels.

Asymmetric dimethylarginine (ADMA) is an endogenous methylated amino acid derived from arginine which can inhibit the activity of nitric oxide synthases. In various pathological states such as hypercholesterolemia, hyperglycemia, hyperhomocysteinemia, hypertension, coronary artery disease, heart failure, and stroke, plasma levels of ADMA may be increased and lead to inhibition of NO synthesis and endothelial dysfunction. Inhibition of ADMA synthesis or intensification of metabolism of this compound might indirectly lower ADMA. Antioxidants, estrogen, vitamin A, angiotensin converting enzyme inhibitors, angiotensin AT1 receptor antagonists, and also some hypolipemic, hypoglycemic and beta-adrenoreceptor blocking drugs decrease ADMA levels. In some situations like neurological disorders, decreased plasma levels of ADMA are noticed and drugs increasing the concentration of this compound could exert protective effects. It is reasonable to explore which drugs can increase or decrease ADMA levels and what their mechanism of that action is.

Temporal correlation analysis of penumbral dynamics in focal cerebral ischemia.

A novel temporal correlation technique was used to map the first-pass transit of iodinated contrast agents through the brain. Transit profiles after bolus injections were measured with dynamic computed tomography (CT) scanning (1 image/s over 50 s). A rabbit model of focal cerebral ischemia (n = 6) was used, and dynamic CT scans were performed at 30, 60, 90, and 120 min postocclusion. Within the ischemic core, no bolus transit was detectable, demonstrating that complete ischemia was present after arterial occlusion. In the periphery of the ischemic distribution, transit dynamics showed smaller peaks, broadened profiles, and overall delay in bolus transit. A cross-correlation method was used to generate maps of delays in ischemic transit profiles compared with normal transit profiles from the contralateral hemisphere. These maps showed that penumbral regions surrounding the ischemic core had significantly delayed bolus transit profiles. Enlargement of the ischemic core over time (from 30 to 120 min postocclusion) was primarily accomplished by the progressive deterioration of the penumbral regions. These results suggest that (a) temporal correlation methods can define regions of abnormal perfusion in focal cerebral ischemia, (b) peripheral regions of focal cerebral ischemia are characterized by delays in bolus transit profiles, and (c) these regions of bolus transit delay deteriorate over time and thus represent a hemodynamic penumbra.

[Chromium carcinogenicity]. / Rakotwórczosc chromu.

Chromium belongs to the group of trace elements hich are essential in numerous functions of the human body. Chromium deficiency may be responsible for various dysfunctions, whereas exposure to chromium at higher concentrations is toxic and may lead to the occurrence of neoplastic diseases. Epidemiological studies of chromium exposure proved its carcinogenity, and thus the IARC recognised Cr(VI) and its compounds as one of ascertained carcinogens. Some findings of these studies were reviewed in the first part of this work. The second part presents some molecular aspects of chromium carcinogenity which are still the subject of medical research. The direct and indirect effects of chromium and its compounds on DNA are analysed as are the relationships between the level of chromium oxidation and carcinogenity, and between the presence of reductants and the kind of DNA damage. Methods for the assessment of chromium mutagenity and genotoxicity are also discussed, and special attention is paid to tests of mutation in bacteria and yeast as well as to sister chromatid exchange (SCE) test.

The protective effect of the Cornus mas fruits (cornelian cherry) on hypertriglyceridemia and atherosclerosis through PPARα activation in hypercholesterolemic rabbits.

Cornelian cherry (Cornus mas L.) fruits have been used in traditional cuisine and in folk medicine in various countries. This study was conducted to evaluate the constituents and impact of cornelian cherry (C. mas L.) fruits lyophilisate on lipid levels, PPARα protein expression, atheromatous changes in the aorta, oxido-redox state, and proinflammatory cytokines in hypercholesterolemic rabbits. The HPLC-MS method was used for determining active constituents in cornelian cherry. In a subsequent in vivo study the protective effect of the cornelian cherry on diet-induced hyperlipidemia was studied using a rabbit model fed 1% cholesterol. Cornelian cherry (100mg/kg b.w.) or simvastatin (5mg/kg b.w.) were administered orally for 60 days. Two iridoids - loganic acid and cornuside - and five anthocyanins were identified as the main constituents of the cornelian cherry. The administering of the cornelian cherry led to a 44% significant decrease in serum triglyceride levels, as well as prevented development of atheromatous changes in the thoracic aorta. Cornelian cherry significantly increased PPARα protein expression in the liver, indicating that its hypolipidemic effect may stem from enhanced fatty acid catabolism. Simvastatin treatment did not affect PPAR-α expression. Moreover, the cornelian cherry had a significant protective effect on diet-induced oxidative stress in the liver, as well as restored upregulated proinflammatory cytokines serum levels. In conclusion, we have shown loganic acid to be the main iridoid constituent in the European cultivar of the cornelian cherry, and proven that the cornelian cherry could have protective effects on diet-induced hypertriglicerydemia and atherosclerosis through enhanced PPARα protein expression and via regulating oxidative stress and inflammation.

Effects of morin-5'-sulfonic acid sodium salt (NaMSA) on cyclophosphamide-induced changes in oxido-redox state in rat liver and kidney.

Cyclophosphamide (CPX) is an anticancer drug with immunosuppressive properties. Its adverse effects are partly connected to the induction of oxidative stress. Some studies indicate that water-soluble derivative of morin-morin-5'-sulfonic acid sodium salt (NaMSA) exhibits strong antioxidant activity. The aim of present study was to evaluate the effect of NaMSA on CPX-induced changes in oxido-redox state in rat. Experiment was carried out on Wistar rats divided in three experimental groups (N = 12) receiving: 0.9% saline, CPX (15 mg/kg) or CPX (15 mg/kg) + NaMSA (100 mg/kg), respectively, and were given intragastrically for 10 days. Malondialdehyde (MDA) and glutathione (GSH) concentrations and superoxide dismutase (SOD) activity were determined in liver and kidneys. Catalase (CAT) activity was assessed only in liver. Treatment with CPX resulted in significant decrease in MDA level in both tissues, which was completely reversed by NaMSA treatment only in liver. In comparison to the control group significant decrease in SOD activity were observed in both tissues of CPX receiving group. In kidneys this parameter was fully restored by NaMSA administration. CPX evoked significant decrease in GSH concentration in kidneys, which was completely reversed by NaMSA treatment. No significant changes were seen in GSH levels and CAT activity between all groups in liver. Results of our study suggest that CPX may exert significant impact on oxido-redox state in both organs. NaMSA fully reversed the CPX-induced changes, especially MDA level in liver, SOD activity and GSH concentration in kidneys and it may be done by enhancement of activity/concentration of endogenous antioxidants.

Betahistine inhibits food intake in rats.

Betahistine, administered intraperitoneally, decreased, in a dose-dependent manner and in a statistically significant degree, total food intake in different experimental models in rats.

Temporal correlation mapping analysis of the hemodynamic penumbra in mutant mice deficient in endothelial nitric oxide synthase gene expression.

BACKGROUND AND PURPOSE: Mice containing deletions in the genes encoding nitric oxide (NO) synthase have been useful to dissect the role of NO in cerebral ischemia. We recently reported that mice lacking expression of the endothelial isoform of NO synthase (eNOS) develop larger infarcts after middle cerebral artery occlusion. Because NO or a related product of NO synthase activity is important for relaxation of cerebral blood vessels, we examined for possible hemodynamic differences in the peri-ischemic zone of eNOS-deficient and wild-type mice after middle cerebral artery occlusion using functional CT scanning techniques. METHODS: Wild-type SV129 mice (n = 10) and mice deficient in eNOS gene expression (n = 10) were subjected to middle cerebral artery occlusion under halothane anesthesia. Thirty minutes after ischemia, functional CT scanning was performed with dynamic scanning protocols to measure the cerebral transit profiles of injected contrast agents. A temporal correlation mapping technique was used to analyze the pattern of hemodynamic perturbations based on alterations in the shape of the cerebral transit profiles. Statistical thresholds defined the hemodynamic core and penumbra. RESULTS: Hemodynamic deficits were more severe in the mutant than wild-type mouse. When expressed as a percentage of the total insult, core areas were significantly increased in mutant mice (39.8 +/- 3.7%) compared with wild types (28.8 +/- 3.4%). Conversely, areas of the hemodynamic penumbra were significantly smaller in mice deficient in eNOS activity (60.2 +/- 3.7%) than in wild-type mice (71.2 +/- 3.4%). Furthermore, the calculated relative perfusion index within the hemodynamic penumbra was significantly lower in the group with eNOS gene deletion (35.6 +/- 1.5% in mutants versus 43.0 +/- 2.4% in wild types). CONCLUSIONS: These data indicate that mice lacking eNOS expression show a greater degree of hemodynamic compromise after middle cerebral artery occlusion and suggest that a product of eNOS activity (eg. NO) may protect brain after focal cerebral ischemia, possibly by improving blood flow within the penumbral zone.

Design and evaluation of nitrosylated alpha-adrenergic receptor antagonists as potential agents for the treatment of impotence.

We designed and evaluated a new class of molecules, nitrosylated alpha-adrenergic receptor antagonists, as potential agents for the treatment of impotence. In in vitro studies with human and rabbit corpus cavernosum strips in organ chambers, the alpha-adrenergic receptor antagonists (alpha-ARAs) moxisylyte and yohimbine and their corresponding nitrosylated compounds, SNO-moxisylyte (NMI-221) and SNO-yohimbine (NMI-187), concentration-dependently relaxed endothelin-induced contraction. The nitrosylated compounds were significantly more potent than the parent alpha-ARA. In human tissues, the specific phosphodiesterase type 5 inhibitor zaprinast potentiated the relaxing effects of the nitrosylated compounds. Only nitrosylated compounds induced accumulation of cyclic GMP in rabbit corpus cavernosum strips. Yohimbine and NMI-187 demonstrated a potent alpha2-blocking activity, with no significant differences in pA2 values (8.9 versus 8.2, respectively). Moxisylyte and NMI-221 showed moderate potency in antagonizing phenylephrine contraction, with comparable pA2 values for both molecules (6.5 versus 6.6, respectively). alpha-Adrenergic receptor-binding studies showed similar binding affinities for the alpha-ARA and their corresponding nitrosylated compounds. In vivo, intracavernosal injection of nitrosylated molecules caused greater increases in intracavernosal pressure (NMI-221 versus moxisylyte) that were more long lasting than those of moxisylyte or yohimbine. There were no significant differences between nitrosylated and non-nitrosylated compounds in the magnitude of systemic mean arterial pressure decrease after intracavernosal injection. alpha-ARA and the nitrosylated compounds showed no pain-inducing activity as evaluated with the paw-lick model in mice. In summary, nitrosylated alpha-ARA have the dual functionalities of nitric oxide donors and alpha-ARA. These drugs induced penile erection in animals, suggesting their possible therapeutic value as agents for the local pharmacological treatment of impotence.