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Obesity affects an increasing number of individuals in the human population and significant importance is attached to research leading to the discovery of drug which would effectively reduce weight. The search for new drugs with anorectic activity and acting within the adrenergic system has attracted the interest of researchers. This study concerns the experimental effects on body weight of α 2 -adrenoceptor antagonists from the group of pyrrolidin-2-one derivatives in rats with diet-induced obesity. Methods: The intrinsic activity of the test compounds at the α-adrenoreceptors was tested. Obesity in rats was obtained by the use of fatty diet and then the influence of the test compounds on body weight, food and water intakes, lipid and glucose profiles and glycerol and cortisol levels were determinated. The effects of the compounds on locomotor activity, body temperature, blood pressure and heart rate were tested. Results: One of the test compounds (1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one) reduces the animal's body weight and the amount of peritoneal adipose tissue during chronic administration, at the same time it does not cause significant adverse effects on the cardiovascular system. This compound decreases temperature and elevates glycerol levels and does not change the locomotor activity and cortisol level at anti-obese dose. Conclusions: Some derivatives of pyrrolidin-2-one that act as antagonists of the α 2 -adrenoreceptor may reduce body weight. Reducing body weight for 1-(3-(4-phenylpiperazin-1-yl)propyl)pyrrolidin-2-one can be associated with decrease in food intake, body fat reduction, reduction of blood glucose, and increased thermogenesis and lipolysis. This effect cannot be the result of changes in spontaneous activity or stress.

Benign prostatic hyperplasia (BPH) is the most common male clinical problem impacting the quality of life of older men. Clinical studies have indicated that the inhibition of &alpha, 1A-/&alpha, 1D adrenoceptors might offer effective therapy in lower urinary tract symptoms. Herein, a limited series of arylsulfonamide derivatives of (aryloxy)ethyl alicyclic amines was designed, synthesized, and biologically evaluated as potent &alpha, 1-adrenoceptor antagonists with uroselective profile. Among them, compound 9 (3-chloro-2-fluoro-N-([1-(2-(2-(2,2,2-trifluoroethoxy)phenoxy]ethyl)piperidin-4-yl)methyl)benzenesulfonamide) behaved as an &alpha, 1D-adrenoceptor antagonist (Ki(&alpha, 1) = 50 nM, EC50(&alpha, 1A) = 0.8 nM, EC50(&alpha, 1D) = 1.1 nM), displayed selectivity over &alpha, 2-adrenoceptors (Ki(&alpha, 2) = 858 nM), and a 5-fold functional preference over the &alpha, 1B subtype. Compound 9 showed adequate metabolic stability in rat-liver microsome assay similar to the reference drug tamsulosin (Clint = 67 and 41 &micro, L/min/mg, respectively). Compound 9 did not decrease systolic and diastolic blood pressure in normotensive anesthetized rats in the dose of 2 mg/kg, i.v. These data support development of uroselective agents in the group of arylsulfonamides of alicyclic amines with potential efficacy in the treatment of lower urinary tract symptoms associated to benign prostatic hyperplasia.

Background Interaction between dopaminergic and nitrergic neurotransmission in the brain plays a crucial role in the control of motor function and in the regulation of blood pressure (BP). In Parkinson’s disease (PD), dopaminergic denervation of the striatum leads to disturbances in the nitrergic system in the basal ganglia. Recently, it has been demonstrated that addition of a low dose of the nitric oxide donor molsidomine to l -DOPA therapy improves dopaminergic neurotransmission in the denervated nigrostriatal system and weakens dyskinesias in rodent models of the disease. Methods The aim of the present study was to examine the impact of chronic administration of molsidomine (2 mg/kg) and l -DOPA (25 mg/kg), alone and in combination, on systolic (SBP) and diastolic (DBP) blood pressure in the anesthetized, unilaterally 6-OHDA-lesioned rats. The measurement of SBP and DBP was performed 24 h after the penultimate and immediately after the last drug doses. Results In 6-OHDA-lesioned rats receiving saline, spontaneous, small decreases in SBP and DBP were observed during the measurements lasting 60 min. Administration of molsidomine alone or in combination with l -DOPA distinctly decreased the BP in 6-OHDA-lesioned rats already after 10 min compared to those treated with saline or l -DOPA alone, respectively. In both groups, the molsidomine-mediated declines in BP persisted till the end of measurement but they disappeared after 24 h. Conclusions Our results indicate that in this PD model molsidomine evokes a short-lasting decrease in BP in contrast to conventional antihypertensive drugs that maintain long-term effect and worsen orthostatic hypotension in parkinsonian patients.

Acute myocardial infarction (AMI) is a leading cause of mortality and morbidity worldwide, especially in developed countries. The most serious problem after myocardial infarction is reperfusion injury that manifests as functional impairment, arrhythmia, and accelerated progression of cell death in certain critically injured myocytes. Subsequently the infarcted myocardium develops features of necrosis and reactive inflammation. To reduce lethal reperfusion injury in patient with AMI antioxidants, anti-inflammatory agents, adenosine, opioids, metabolic modulators (glucose, insulin, and potassium, nicorandil and agents which reduce intracellular Ca(2+) overload and inhibit Na(+)-H(+) exchange) are used. In this study a novel compound (compound 9) 1-(1 h-indol-4-yloxy)-3-{[2-(2-methoxyphenoxy) ethyl]amino}propan-2-ol and its enantiomers are examined in arrhythmia associated with coronary artery occlusion and reperfusion in a rat model. Antioxidant properties are also determined for test compounds using the malondialdehyde (MDA) lipid peroxidation and ferric reducing antioxidant power (FRAP) tests. In summary, the tested compounds, especially the S enantiomer has a strong antiarrhythmic activity in a model of occlusion and reperfusion of the left coronary artery which is probably related to their adrenolytic action. In contrast to carvedilol, none of the test compound reduced the lipid peroxidation but increased ferric reducing antioxidant power. In the antioxidant effect, there was no difference between the optical forms of compound 9.

Older and even new antidepressants cause adverse effects, such as orthostatic hypotension, hyper- or hypoglycemia, liver injury or lipid disorders. In our previous experiments we showed significant antidepressant- and anxiolytic-like activities of dual 5-HT1A and 5-HT7 antagonists with α1-adrenolitic properties i.e. 1-[(2,6-dimethylphenoxy)ethoxyethyl]-4-(2-methoxyphenyl)piperazine hydrochloride (HBK-14) and 1-[(2-chloro-6-methylphenoxy)ethoxyethyl]-4-(2-methoxyphenyl)piperazine hydrochloride (HBK-15). Here, we evaluated the influence of chronic administration of HBK-14 and HBK-15 on blood pressure (non-invasive blood pressure measurement system for rodents), lipid profile (total cholesterol, low density lipoproteins-LDL, high density lipoproteins-HDL, triglycerides), glucose level, and liver enzymes activity (aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transferase). We determined potential antihistaminic (isolated guinea pig ileum) and antioxidant properties (ferric reducing ability of plasma-FRAP, non-protein thiols-NPSH, stable free radical diphenylpicrylhydrazyl-DPPH) cytotoxicity. Our experiments revealed that HBK-14 and HBK-15 did not influence blood pressure, lipid profile, glucose level or liver enzymes activity in rats after 2-week treatment. We also showed that none of the compounds possessed antioxidant or cytotoxic properties at antidepressant- and anxiolytic-like doses. HBK-14 and HBK-15 very weakly blocked H1 receptors in guinea pig ileum. Positive results of our preliminary experiments on the safety of HBK-14 and HBK-15 encourage further studies concerning their effectiveness in the treatment of depression and/or anxiety disorders.

Background Lipoic acid (LA) was shown to possess anti-inflammatory properties. In this study, we present evidence supporting the hypothesis that the anti-inflammatory properties of LA are associated with the formation of hydrogen sulfide (H 2 S). Methods The study was conducted on male albino Swiss mice. The animals were treated with carrageenan by subcutaneous ( sc ) injection into the right hind paw to induce acute inflammation. Animals were treated intraperitoneally ( ip ) with LA (30, 50 and 100 mg/kg) or indomethacin (20 mg/kg) 30 min before carrageenan administration. The control group was given ip the vehicle (1% Tween 80) 30 min before carrageenan administration. Additional experiment involved ip combined treatment of mice with glibenclamide (10 mg/kg) or glibenclamide (10 mg/kg) and LA(100 mg/kg) 30 min before carrageenan administration. LA, indomethacin and glibenclamide were suspended in 1% Tween 80. At 1, 2 and 3 h after treatment with carrageenan the degree of the paw edema was evaluated by the measurement of the paw volume using aqueous plethysmometer. Results Injection of carrageenan into the mouse hind paw increased paw volume. The increase in paw edema was completely suppressed by pretreatment with LA. The reduction of paw edema by LAwas abolished by pretreatment with the K ATP channel antagonist, glibenclamide. Conclusion Our findings demonstrate for the first time in vivo that the anti-inflammatory activity of LA might be connected with the formation of H 2 S.

Background Nanoparticles (a part of matter which size is less than 100 nm) have numerous potential applications in biomedicine, due to their unique surface, electronic and optical properties. The goal of the present study was to examine the distribution of gold nanoparticles (GNPs) in mice after single intravenous administration. Methods Spherical GNPs were synthesized by chemical reduction of tetrachloroauric acid with ascorbic acid as a reductant. GNPs were stabilized using polyvinyl alcohol (PVA, m.w. = 67000Da) a substance approved for use in the pharmaceutical industry. The size of colloidal gold particles (diameter equals 25 ± 8 nm) was determined using HR SEM and DLS techniques; ς potential of GNPs was determined using Malvern Zetasizer Nano ZS and it equals –5.2 ± 5.4 mV. An aqueous dispersion of GNPs was administered to mice in a dose of about 10 cm 3 /kg and 24 h later the amount of gold in different organs was determined using the inductively coupled plasma mass spectrometer (ICP MS). Initial concentration of GNPs equals 29.55 mg/l. Results GNPs after single intravenous administration preferentially accumulated in the liver (12.7 % of the applied dose), while the other organs accumulated around 0.1 % or less. Conclusion Colloidal GNPs of the used size (about 25 ± 8 nm) provide new potential route for direct delivery system to the liver, which may be important e.g., in liver cancer diagnosis.

The search for drugs with anorectic activity, acting within the adrenergic system has attracted the interest of researchers. Partial α2-adrenoceptor agonists might offer the potential for effective and safe treatment of obesity. We compared the effectiveness and safety of α2-adrenoceptor ligands in reducing body mass. We also analyzed if antagonist and partial agonists of α2-adrenoceptor--yohimbine and guanfacine--act similarly, and determined which course of action is connected with anorectic activity. We tested intrinsic activity and effect on the lipolysis of these compounds in cell cultures, evaluated their effect on meal size, body weight in Wistar rats with high-fat diet-induced obesity, and determined their effect on blood pressure, heart rate, lipid profile, spontaneous locomotor activity, core temperature and glucose, as well as glycerol and cortisol levels. Both guanfacine and yohimbine showed anorectic activity. Guanfacine was much more effective than yohimbine. Both significantly reduced the amount of intraperitoneal adipose tissue and had a beneficial effect on lipid profiles. Decreased response of α2A-adrenoceptors and partial stimulation of α2B-receptors seem to be responsible for the anorectic action of guanfacine. The stimulation of α1-adrenoceptors by guanfacine is responsible for cardiovascular side effects but may also be linked with improved anorexic effect. α1-adrenoceptor blockade is connected with the side effects of yohimbine, but it is also associated with the improvement of lipid profiles. Guanfacine has been approved by the Food and Drug Administration (FDA) to treat hypertension and conduct disorder, but as it reduces body weight, it is worth examining its effectiveness and safety in models of obesity.