Theranostic properties of a survivin-directed molecular beacon in human melanoma cells.

Survivin is an inhibitor of apoptosis overexpressed in different types of tumors and undetectable in most terminally differentiated normal tissues. In the current study, we sought to evaluate the in vitro theranostic properties of a molecular beacon-oligodeoxynucleotide (MB) that targets survivin mRNA. We used laser scanning confocal microscopy to study MB delivery in living cells and real-time PCR and western blot to assess selective survivin-targeting in human malignant melanoma cells.

Anticancer activity of anandamide in human cutaneous melanoma cells.

Cannabinoids are implicated in the control of cell proliferation, but little is known about the role of the endocannabinoid system in human malignant melanoma. This study was aimed at characterizing the in vitro antitumor activity of anandamide (AEA) in A375 melanoma cells. The mRNA expression of genes that code for proteins involved in the metabolism and in the mechanism of AEA action was assessed by RT-PCR.

1,2,3-Triazol-carboxanilides and 1,2,3-triazol-(N-benzyl)-carboxamides as BK-potassium channel activators. XII.

The chemical structures of many synthetic activators of large-conductance calcium-activated potassium channels (BK channels) satisfy a simple pharmacophore model, consisting of two appropriately substituted phenyl rings connected by a linker of a heterogeneous nature. In this paper, a series of new compounds with modifications of the linker portion of the above pharmacophore are described. In particular, in these new derivatives, the linker portion is represented by a 1,2,3-triazole-carboxamide group, which can be viewed as a combination of two different kinds of linker, independently used in previous series of BK-openers: the amide function and the 1,2,3-triazole ring.

In vivo adenosine A(2B) receptor desensitization in guinea-pig airway smooth muscle: implications for asthma.

This study was aimed at characterizing the role of adenosine receptor subtypes in the contractility modulation of guinea-pig airway smooth muscle in normal and pathological settings. In vitro and in vivo experiments were performed by testing selective agonists and antagonists on isolated tracheal smooth muscle preparations and pulmonary inflation pressure, respectively, under normal conditions or following ovalbumin-induced allergic sensitization. In normal and sensitized animals, the adenosine A(2A)/A(2B) receptor agonist, NECA, evoked relaxing responses of isolated tracheal preparations precontracted with histamine, and such an effect was reversed by the adenosine A(2B) antagonist, MRS 1706, in the presence or in the absence of epithelium.

New amido derivatives as potential BKCa potassium channel activators. XI.

The vasorelaxing effects of exogenous activators of large-conductance calcium-activated potassium channels (BK channels) can furnish the pharmacological rational basis for the treatment of hypertension and/or other diseases related with an impaired contractility of vessels. Since in previous works some benzanilide derivatives showed BK channel-induced vasorelaxing activity, in this paper we have taken into consideration the introduction of methylene spacer(s) between the amide linker and one or both the aromatic substituents, to evaluate the pharmacological effect caused by these lengthenings and to obtain possible useful information about structure-activity relationships. Overall, the main findings of this work suggest that the introduction of one or two methylene group(s) in the amide linker exerts a negative influence on the BK-opening properties, which can be due to an excessive lengthening of the spacer between the two aromatic rings and/or to further degrees of conformational freedom.

Functional contribution of the endothelial component to the vasorelaxing effect of resveratrol and NS 1619, activators of the large-conductance calcium-activated potassium channels.

Large-conductance calcium-activated potassium channels (BK) of smooth muscle play a role in the relevant modulation of vascular tone, due to their calcium- and voltage-dependent mechanisms of activation. A potential role of endothelial BK channels has also been suggested by approaches on endothelial cell cultures. However, no functional study, aimed at evaluating the contribution of endothelial BK channels to the effect of BK-openers, has been reported.

Sequence characterized amplified region (SCAR) analysis on DNA from the three medicinal Echinacea species.

In our previous study, RAPD (Random Amplified Polymorphic DNA) analysis revealed species-specific markers for three medicinal Echinacea species (Asteraceae): E. angustifolia DC., E.

Structural modifications of benzanilide derivatives, effective potassium channel openers. X.

Large-conductance calcium-activated potassium (BK) channels are involved in many fundamental cell functions. Consistently, the ability to activate BK channels by exogenous compounds is considered as a promising pharmacodynamic pattern for the potential treatment of several pathologies. In this perspective, the development of new and selective BK-openers can be considered as an actual field of research.

Heterocyclic analogs of benzanilide derivatives as potassium channel activators. IX.

On the basis of our previous works, addressed to synthesise new activators of BK potassium channels, and of many suggestions from the international literature, a simple pharmacophoric model, consisting of two suitably substituted phenyl rings bound to various kinds of linkers, was hypothesised. In particular, the effectiveness of the amidic linker was demonstrated, since several benzanilide derivatives showed interesting BK-opener properties. As a development of these benzanilides, in this work we introduced heterocyclic substituents, replacing the aryl ring on the acid side or on the basic one of the amide linker of the above pharmacophore.

New NO-releasing pharmacodynamic hybrids of losartan and its active metabolite: design, synthesis, and biopharmacological properties.

In a preliminary work, we reported two NO-sartans, possessing the characteristics of an AT(1) antagonist and a "slow NO donor", obtained by adding NO-donor side chains to losartan 1. The NO release from an NO-sartan should be modulated in order to strengthen the antihypertensive activity of the native drug and to ensure additional effects, such as the antiplatelet and anti-ischemic ones. To obtain a collection of prototypical NO-sartans, showing different rates of NO release, new NO-donor moieties have been linked to 1 or its active metabolite 2 (EXP 3174).

Benzoyl and/or benzyl substituted 1,2,3-triazoles as potassium channel activators. VIII.

This paper reports the preparation of new benzoyl and/or benzyl substituted 1,2,3-triazole derivatives and their pharmacological evaluation as potential BK channel openers, as a part of a research program which hypothesized a pharmacophoric structure containing the 1,2,3-triazole ring. The synthetic procedures consist essentially with the 1,3-dipolar cycloaddition of aryl or benzyl azides to the asymmetric alkyne benzoylacetylene to give the wished 4-benzoyl-1,2,3-triazole isomers in larger amount. The pharmacological results show that the 1-(2-hydroxybenzyl)-4-benzyl-1H-1,2,3-triazole possesses high vasorelaxing activity involving the opening of the BK channels.

1,4- and 2,4-substituted-1,2,3-triazoles as potential potassium channel activators. VII.

New 1,4- and 2,4-substituted 1,2,3-triazole derivatives were synthesized and tested as potential BK(Ca) channel openers, as a part of a research program, which hypothesizes a pharmacophoric structure containing the 1,2,3-triazole ring. The structure-activity relationships were studied introducing some structural changes concerning molecular geometry and the presence of a hydrogen bond donor as a primary amino group and a phenolic or alcoholic hydroxy function. The compounds were prepared by nucleophilic substitution on the 1,2,3-triazole ring and by 1,3-dipolar cycloaddition of azides to selected alkynes and to phenylacetone.

Drug-induced block of cardiac HERG potassium channels and development of torsade de pointes arrhythmias: the case of antipsychotics.

The prolongation of the cardiac repolarization process, a result of the blocking of the Human Ether-ago-go Related Gene potassium channel, is an undesired accessory property shared by many pharmacological classes of non-cardiovascular drugs. Often the delayed cardiac repolarization process can be identified by a prolongation of the QT interval of the electrocardiograph. In these conditions, premature action potentials can trigger a dangerous polymorphic ventricular tachyarrhythmia, known as torsade de pointes, which occasionally can result in lethal ventricular fibrillation.

Vasorelaxant effects of the chloroformic crude extract of Bupleurum fruticosum L. (Umbelliferae) roots on rat thoracic aorta.

The chloroformic crude extract of roots of Bupleurum fruticosum L. (Umbelliferae) showed a concentration-dependent vasorelaxing effect on aortic rings endothelium-deprived and pre-contracted by norepinephrine (NE). The pharmacological effect was not produced through the stimulation of cyclooxygenase, adenyl cyclase, or guanylyl cyclase, since selective inhibitors did not prevent the extract-induced responses.

NO-sartans: a new class of pharmacodynamic hybrids as cardiovascular drugs.

The aim of this work was to develop lead pharmacodynamic hybrids, NO-sartans, possessing the characteristics of a typical AT1-antagonist and of a "slow NO donor", by adding NO-donor side chains to losartan. These new compounds, 2a and 2b, displayed vasorelaxing effects, due to the release of NO, and antagonized the vasocontractile effects of angiotensin II, with potency values similar to that of losartan. In vivo, the antihypertensive effects of 2a were similar to those of losartan and captopril.

Vasorelaxing effects of flavonoids: investigation on the possible involvement of potassium channels.

A flavonoid-rich diet has been associated with a lower incidence of cardiovascular diseases, probably because of the antioxidant and vasoactive properties of flavonoids. Indeed, many flavonoids show vasorelaxing properties, due to different and often not yet completely clarified mechanisms of action. Among them, the activation of vascular potassium channels has been indicated as a possible pathway, accounting, at least in part, for the vasodilatory action of some flavonoid derivatives, such as apigenin and dioclein.

Synthesis and biological activity of novel substituted benzanilides as potassium channel activators. V.

As part of our program toward designing potassium channel openers, the synthesis of a novel series of substituted benzanilides and their vasodilating activity are presented. The facile synthetic pathway generally involves coupling between the appropriate benzoyl chloride and commercial available anilines, followed by the selective or non-selective cleavage of methyl ether substituent(s), affording the corresponding phenol or bisphenol derivatives. The pharmacological evaluation of these structurally novel potential BK-openers on vascular contractile activity was studied in vitro, using isolated rat aortic rings pre-contracted with KCl 20 mM.

Vasodilator activity of Michelia figo Spreng. (Magnoliaceae) by in vitro functional study.

The methanolic extract of leaves of Michelia figo Spreng. (Magnoliaceae), as well as several purified fractions, showed a concentration-dependent vasorelaxing effect on aortic rings endothelium-deprived and pre-contracted by norepinephrine (NE). For further pharmacological investigation on the mechanism of action, the fraction S4 was selected, since it showed the best vasodilator properties.

1,5-Diarylsubstituted 1,2,3-triazoles as potassium channel activators. VI.

As part of our program toward designing potassium channel openers, synthesis of a novel series of 1,5-diphenylsubstituted 1,2,3-triazoles, as potential activators of the large-conductance calcium-activated potassium channels (BK), as well as their vasorelaxant activity are presented. The functional effect of these potential structurally novel BK-openers on vascular contractile function were studied in vitro, using isolated rat aortic rings pre-contracted with KCl 20 mM. Among the target compounds, only 16 showed appreciable effectiveness, exhibiting an efficacy parameter (57%) lower than that of NS1619 and a comparable potency index (pIC50: 5.

CB1- and CB2-cannabinoid receptor-independent lipolysis induced by WIN 55,212-2 in male rat adipocytes.

The expression of genes encoding the cannabinoid CB(1) and CB(2) receptors and fatty acid amide hydrolase (FAAH) and the lipolytic activity of cannabinoid agonists were investigated in rat adipose tissue.RT-PCR studies indicated that the genes encoding CB(1) and CB(2) receptors and FAAH are not expressed in epididymal adipocytes. In functional studies, the non-selective cannabinoid receptor agonist WIN 55,212-2 concentration-dependently (0.

The xanthones gentiacaulein and gentiakochianin are responsible for the vasodilator action of the roots of Gentiana kochiana.

Gentiana kochiana Perr. et Song. (Gentianaceae), a plant used in the traditional medicine of Tuscany (Italy) as antihypertensive remedy, exerts a vasodilator action on in vitro aortic rings that is probably linked to the blocking of the ryanodine-sensitive Ca++ channels.

Effects of cannabinoids on non-adrenergic non-cholinergic-mediated relaxation in guinea-pig trachea.

The effects of cannabinoid receptor agonists on the non-adrenergic non-cholinergic (NANC) inhibitory responses to electrical field stimulation in guinea-pig trachea were assessed. R-(+)-[2,3-dihydro-5-methyl-3-[(morpholilinyl) methyl]pyrrolo [1,2,3-de]-1,4-benzoxazin-6-yl]-(1-naphthalenyl)methanone mesylate (WIN 55,212-2; 10(-5) M) significantly enhanced the frequency-dependent response to electrical stimulation. The same concentration of R-(N)-(2-hydroxy-1-methylethyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (R(+)methanandamide) and 1-propyl-2-methyl-3-(1-naphthoyl)indole (JWH-015) did not affect significantly the electrically induced inhibitory NANC responses.

Highly potent 1,4-benzothiazine derivatives as K(ATP)-channel openers.

A series of 1,4-benzothiazines, suitably functionalized at the N-4 and C-6 positions, arising from the replacement of a benzopyran-based structure of cromakalim with a 1,4-benzothiazine nucleus, has been synthesized as potassium channel openers (KCOs). Most of the tested compounds show high vasorelaxant potency that is considerably higher than that of the reference levcromakalim (LCRK). In the presence of the well-established selective K(ATP) blocker, glibenclamide, the vasorelaxing effects were antagonized in a competitive fashion, indicating the involvement of the K(ATP) channel in their pharmacological effect.

R+-methanandamide inhibits tracheal response to endogenously released acetylcholine via capsazepine-sensitive receptors.

The effects of cannabinoid drugs on the cholinergic response evoked by electrical field stimulation (0.2 ms pulse width, 20 V amplitude, 10 Hz, 7.5 s train duration) in guinea-pig tracheal preparations were investigated.

Cardiovascular effects of Urtica dioica L. (Urticaceae) roots extracts: in vitro and in vivo pharmacological studies.

Urtica dioica (Urticaceae) is a plant principally used in the traditional medicine of oriental Marocco as antihypertensive remedy (J. Ethnopharmacol., 58 (1997), 45).