Neutral high-generation phosphorus dendrimers inhibit macrophage-mediated inflammatory response in vitro and in vivo.

Inflammation is part of the physiological response of the organism to infectious diseases caused by organisms such as bacteria, viruses, fungi, or parasites. Innate immunity, mediated by mononuclear phagocytes, including monocytes and macrophages, is a first line of defense against infectious diseases and plays a key role triggering the delayed adaptive response that ensures an efficient defense against pathogens. Monocytes and macrophages stimulation by pathogen antigens results in activation of different signaling pathways leading to the release of proinflammatory cytokines. However, inflammation can also participate in the pathogenesis of several diseases, the autoimmune diseases that represent a relevant burden for human health. Dendrimers are branched, multivalent nanoparticles with a well-defined structure that have a high potential for biomedical applications. To explore new approaches to fight against the negative aspects of inflammation, we have used neutral high-generation phosphorus dendrimers bearing 48 (G3) or 96 (G4) bisphosphonate groups on their surface. These dendrimers show no toxicity and have good solubility and chemical stability in aqueous solutions. Here, we present data indicating that neutral phosphorus dendrimers show impressive antiinflammatory activities both in vitro and in vivo. In vitro, these dendrimers reduced the secretion of proinflammatory cytokines from mice and human monocyte-derived macrophages. In addition, these molecules present efficient antiinflammatory activity in vivo in a mouse model of subchronic inflammation. Taken together, these data suggest that neutral G3-G4 phosphorus dendrimers have strong potential applications in the therapy of inflammation and, likely, of autoimmune diseases.

From metallodrugs to metallodendrimers for nanotherapy in oncology: a concise overview.

Metallodrugs (organometallic complexes) bearing at least one metal-carbon bond - represent original and powerful tools for diverse therapeutic applications based on the development of "bioorganometallic chemistry". To date, various metallodrugs were described with very interesting biological activities as antimalarials, antibacterials, neuroprotectors, against arthritis, for chemotherapy etc. Anticancer Pt-based drugs are the main complexes used in the treatment of several cancers, but unfortunately these complexes show elicit and severe toxicities and resistance effects. The remarkably unique and tunable properties of dendrimers have made them promising tools for diverse biomedical applications such as diagnostics, gene therapy and drug delivery including in oncology. Recent studies have shown that well designed dendritic carriers overcome such as poor solubility, permeability, biocompatibility, bioavailability and toxicity of the native drug. This review reports on the recent advances for the use of metallodrugs and dendritic based carriers (drug-dendrimer conjugates and drug encapsulation) in oncology. Advantages, limitations and opportunities in oncology of such materials are discussed and compared.

Contrast-enhanced US and MRI for assessing the response of breast cancer to neoadjuvant chemotherapy().

PURPOSE: To evaluate the response of breast cancers to neoadjuvant chemotherapy (NAC) with second-generation contrast-enhanced ultrasound (CEUS) and magnetic resonance (MR). MATERIALS AND METHODS: We studied 16 women aged 33-74 years (mean, 53 years; median, 38 years) with locally advanced breast carcinoma or large operable breast cancer (>2 cm; T2-T4, N0-N3, M0) that had been detected by mammography, conventional ultrasonography, and biopsy. CEUS (with SonoVue, 5 ml) and MR (with Gd-DTPA; 0.2 mM/kg) were performed under blinded conditions before, during, and after 6-8 cycles of NAC. Lesions were measured and time/signal intensity (T/SI) curves were calculated during both the examinations. The data obtained were analyzed in light of the results of surgical pathology. RESULTS: Six patients had complete responses manifested by the disappearance of enhancement at both CEUS and MR. Six others had partial responses (reduction of lesion enhancement >50%). In 5/6, T/SI curves obtained with CEUS and MR were both indicative of malignancy (flat curves at CEUS, type I curves at MR); the sixth had a discontinuous curve at CEUS and a type II curve at MR. Four patients had lesional enhancement reductions of <50%. In 3, concordant pictures emerged from the analysis of T/SI curves (discontinuous curves in CEUS, type II and III curves in MR); the fourth had a flat CEUS curve and a type I MR curve. Responses to NAC classified on the basis of MR and CEUS findings showed good correlation with the pathological response. CONCLUSIONS: T/SI curves recorded during CEUS correlate with those obtained during MR and may be a valid index of response to the therapy.

RPR 119990, a novel alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid antagonist: synthesis, pharmacological properties, and activity in an animal model of amyotrophic lateral sclerosis.

Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor antagonists are of potential interest for the treatment of certain acute and chronic neurodegenerative diseases, including amyotrophic lateral sclerosis. Here, we describe the synthesis and pharmacological properties of 9-carboxymethyl-4-oxo-5H,10H-imidazo[1,2-a]indeno[1,2-e]pyrazin-2-phosphonic acid (RPR 119990). The compound displaced [3H]AMPA from rat cortex membranes with a K(i) of 107 nM. In oocytes expressing human recombinant AMPA receptors, RPR 119990 depressed ion flux with a K(B) of 71 nM. The antagonist properties of this compound were confirmed on rat native AMPA receptors in cerebella granule neurons in culture and in hippocampal slices where it antagonized electrophysiological responses with IC50 values of 50 and 93 nM, respectively. RPR 119990 antagonized hippocampal evoked responses in vivo, demonstrating brain penetration at active concentrations. RPR 119990 is a potent anticonvulsant in the supramaximal electroshock in the mouse with an ED50 of 2.3 mg/kg 1 h post s.c. administration, giving it a workably long action. Pharmacokinetic studies show good passage into the plasma after subcutaneous administration, whereas brain penetration is low but with slow elimination. This compound was found active in a transgenic mouse model of familial amyotrophic lateral sclerosis (SOD1-G93A) where it was able to improve grip muscle strength and glutamate uptake from spinal synaptosomal preparations, and prolong survival with a daily dose of 3 mg/kg s.c.

Synthesis of anticonvulsive AMPA antagonists: 4-oxo-10-substituted-imidaz.

The overstimulation of excitatory amino acid receptors such as the glutamate AMPA receptor has been implicated in the physiopathogenesis of epilepsy as well as in acute and chronic neurodegenerative disorders. An original series of readily water soluble 4-oxo-10-substituted-imidazo[1,2-a]indeno[1,2-e]pyrazin-2-carboxylic acid derivatives was synthesized. The most potent derivative 6a exhibited nanomolar binding affinity (IC50 = 35nM) and antagonist activity (IC50 = 6nM) at ionotropic AMPA receptor. This compound also demonstrated potent anticonvulsant properties in MES in mice and rats with long durations of action with ED50 values in the 1-3 mg/kg dose range following ip and iv administration.

Bioisosteres of 9-carboxymethyl-4-oxo-imidazo[1,2-a]indeno-[1,2-e]pyrazin-2-carboxylic acid derivatives. Progress towards selective, potent in vivo AMPA antagonists with longer durations of action.

A novel series of 2- and 9-disubstituted heterocyclic-fused 4-oxo-indeno[1,2-e]pyrazin derivatives was synthesized. One of them, the 9-(1H-tetrazol-5-ylmethyl)-4-oxo-5,10-dihydroimidazo[1,2-a]indeno[1,2-e]pyrazin-2-yl phosphonic acid 4i exhibited a strong and a selective binding affinity for the AMPA receptor (IC50 = 13 nM) and demonstrated potent antagonist activity (IC50 = 6nM) at the ionotropic AMPA receptor. This compound also displayed good anticonvulsant properties against electrically-induced convulsions after ip and iv administration with ED50 values between 0.8 and 1 mg/kg. Furthermore, a strong increase in potency was observed when given iv 3 h before test (ED50 = 3.5 instead of 25.6 mg/kg for the corresponding 9-carboxymethyl-2-carboxylic acid analogue). These data confirmed that there is an advantage in replacing the classical carboxy substituents by their bioisosteres such as tetrazole or phosphonic acid groups.

8-Methylureido-10-amino-10-methyl-imidazo[1,2-a]indeno[1,2-e] pyrazine-4-ones: highly in vivo potent and selective AMPA receptor antagonists.

Water soluble 8-methylureido-10-amino-10-methyl-imidazo[1,2-a]indeno[1,2-e]pyraz ine-4-one 4 represents a novel class of highly potent and selective AMPA receptors antagonists with in vivo activity. The dextrorotatory isomer (+)-4 was found to display the highest affinity with an IC50 of 10 nM. It also exhibited very good anticonvulsant effects after i.p., s.c. and i.v. administration in mice subjected to electrical convulsions (MES) and i.p. in audiogenic seizure-e in DBA/2 mice (ED50's < or = 10 mg/kg).

Indeno[1,2-b]pyrazin-2,3-diones: a new class of antagonists at the glycine site of the NMDA receptor with potent in vivo activity.

Indeno¿1,2-bpyrazin-2,3-diones have been identified as a novel series of potent ligands on the glycine site of the NMDA receptor. To improve their in vivo activities, an acetic acid-type side chain was introduced to the 5-position, giving water-soluble compounds when formulated as the sodium salt (>10 mg/mL). Introduction of a chlorine atom in the 8-position led to a dramatic improvement of anticonvulsant activity and this was surprising since this change did not improve binding affinity. A plausible explanation is a reduced recognition by a Na(+),K(+)-ATPase active transport system responsible for the excretion of these compounds from the brain and kidney. This promising new chemical series led to the optically active isomer (-)-10i (RPR 118723), a glycine/NMDA antagonist with nanomolar binding affinity and in vivo activity in animal model of convulsions and electrophysiology at doses in the range of 2-3 mg/kg following iv administration.

4,10-Dihydro-4-oxo-4H-imidazo[1,2-a]indeno[1,2-e]pyrazin-2-carboxylic acid derivatives: highly potent and selective AMPA receptors antagonists with in vivo activity.

A novel series of 2-substituted-4,5-dihydro-4-oxo-4H-imidazo[1,2-a]indeno[1,2-e]pyrazine derivatives was synthesised. One of them, 4e-a highly water soluble compound exhibited a nanomolar affinity and demonstrated competitive antagonist properties at the ionotropic AMPA receptors. This compound also displayed potent anticonvulsant properties against electrically or sound-induced convulsions in mice after systemic administration, thus suggesting adequate brain penetration.

8-Methylureido-4,5-dihydro-4-oxo-10H-imidazo[1,2-a]indeno[1,2-e]pyrazines: highly potent in vivo AMPA antagonists.

A novel series of readily water soluble 8-methylureido-4,5-dihydro-4-oxo-10H-imidazo[1,2-a]indeno[1,2-e]++ +pyrazines were synthesized. The -10-yl acetic acid ((+)-3) and -10-carboxylidene (4) derivatives exhibit potent affinities (IC50=4 and 19 nM, respectively) and antagonist properties (IC50 = 2 and 3 nM, respectively) at the ionotropic AMPA receptor. These compounds also display anticonvulsant properties against both electrically and sound-induced convulsions in mice after ip, sc and iv administration with ED50 values between 0.9 and 11 mg/kg, thus suggesting adequate brain penetration.

Synthesis and potent anticonvulsant activities of 4-oxo-imidazo[1,2-a]inden.

The over-stimulation of excitatory amino acid receptors such as the glutamate AMPA receptor has been suggested to be associated with neurodegenerative disorders. Here we describe an original series of readily water soluble 4-oxo-imidazo[1,2-a] indeno[1,2-e]pyrazin-8- and -9-carboxylic (acetic) acid derivatives. One of these compounds, 4f, exhibited nanomolar binding affinity, potent competitive antagonism at the ionotropic AMPA receptor and a long duration of anticonvulsant activity after administration by parenteral route in vivo.

Spiro-imidazo[1,2-a]indeno[1,2-e]pyrazine-4-one derivatives are mixed AMPA and NMDA glycine-site antagonists active in vivo.

Original spiro-imidazo[1,2-a]indeno[1,2-e]pyrazine-4-one derivatives were synthesised and led to the identification of 3e which showed good affinities for both the AMPA and the NMDA glycine-site receptors, and displayed good anticonvulsant effects after i.p. and i.v. administrations in the electroshock-induced convulsion assay in mice. The corresponding dextrorotatory isomer (+)-3e was notably more potent than the levorotatory isomer (-)-3e in in vitro and in vivo assays.

Riluzole series. Synthesis and in vivo "antiglutamate" activity of 6-substituted-2-benzothiazolamines and 3-substituted-2-imino-benzothiazolines.

Two series of analogues of riluzole, a blocker of excitatory amino acid mediated neurotransmission, have been synthesized: monosubstituted 2-benzothiazolamines and 3-substituted derivatives. Of all the compounds prepared in the first series, only 2-benzothiazolamines bearing alkyl, polyfluoroalkyl, or polyfluoroalkoxy substituents in the 6-position showed potent anticonvulsant activity against administration of glutamic acid in rats. The most active compounds displaying in vivo "antiglutamate" activity were the 6-OCF(3) (riluzole), 6-OCF(2)CF(3), 6-CF(3), and 6-CF(2)CF(3) substituted derivatives with ED(50) values between 2.5 and 3.2 mg/kg i.p. Among the second series of variously substituted benzothiazolines, compounds as active as riluzole or up to 3 times more potent were identified in two series: benzothiazolines bearing a beta-dialkylaminoethyl moiety and compounds with an alkylthioalkyl chain and their corresponding sulfoxides and sulfones. The most potent derivatives were 2-imino-3-(2-methylthio)- and 2-imino-3-(2-methylsulfinyl)-ethyl-6-trifluoromethoxybenzothiazolines (61 and 64, ED(50) = 1.0 and 1.1 mg/kg i.p., respectively). In addition, intraperitoneal administration of some of the best benzothiazolines protected mice from mortality produced by hypobaric hypoxia.

The naphtosultam derivative RP 62203 (fananserin) has high affinity for the dopamine D4 receptor.

The dopamine D4 receptor is a potential target for novel antipsychotic drugs. Most available compounds with affinity for the dopamine D4 receptor also bind to dopamine D2 receptors. This report describe the affinity of the 5-HT2A receptor antagonist RP 62203 (fananserin) for the human dopamine D4 receptor. Fananserin displaces [3H]spiperone binding to recombinant human dopamine D4 receptors with a Ki of 2.93 nM. This compares with an affinity (Ki) of 0.37 nM for the rat 5-HT2A receptor and of 726 mM for the rat dopamine D2 receptor. [3H]Fananserin can be used to label the recombinant dopamine D4 receptor expressed in Chinese hamster ovary cells with a KD of 0.725 nM. Fananserin is, thus, the first compound to be reported that distinguishes between dopamine D4 and D2 receptors.

Neuroprotective effects of RPR 104632, a novel antagonist at the glycine site of the NMDA receptor, in vitro.

The NMDA antagonist and neuroprotective effects of RPR 104632 (2H-1,2,4-benzothiadiazine-1-dioxide-3-carboxylic acid), a new benzothiadiazine derivative, with affinity for the glycine site of the NMDA receptor-channel complex are described. RPR 104632 antagonized the binding of [3H]5,7-dichlorokynurenic acid to the rat cerebral cortex, with a Ki of 4.9 nM. This effect was stereospecific, since the (-)-isomer was 500-fold more potent than the (+)-isomer. The potent affinity of RPR 104632 for the glycine site was confirmed by the observation that RPR 104632 inhibited [3H]N-[1-(2-thienyl)cyclohexyl]-3,4-piperidine ([3H]TCP) binding in the presence of N-methyl-D-aspartate (NMDA) (IC50 = 55 nM), whereas it had no effect on the competitive NMDA site or on the dissociative anaesthetic site. RPR 104632 inhibited the NMDA-evoked increase in guanosine 3',5'-cyclic monophosphate (cGMP) levels of neonatal rat cerebellar slices (IC50 = 890 nM) in a non-competitive manner and markedly reduced NMDA-induced neurotoxicity in rat hippocampal slices and in cortical primary cell cultures. These results suggest that RPR 104632 is a high-affinity specific antagonist of the glycine site coupled to the NMDA receptor channel with potent neuroprotective properties in vitro.

Microcalcifications in ductal carcinoma in situ of the breast: histochemical and immunohistochemical study.

Thirty cases of ductal carcinoma in situ (DCIS) of the breast, showing histological microcalcifications, were studied to clarify their mechanism of formation. Undecalcified sections revealed three types of calcium precipitates: type I and II granular calcifications (GCs) and laminar calcifications (LCs). In type I GCs the core on which the calcium had deposited was constituted mainly by nuclear debris. Type II GCs were predominantly composed by mucosubstances. LCs were the result of calcium deposits on mucoid or proteinaceous material, arranged in concentric lamellae. LCs and type II GCs were mainly present in well and intermediately differentiated DCIS. Type I GCs were observed in only DCIS with necrosis, frequently being present in intermediately and poorly differentiated DCIS.

New indole derivatives as potent and selective serotonin uptake inhibitors.

A series of new indole derivatives (2-28) has been prepared in the search for novel 5-HT uptake inhibitors. These compounds were obtained by the condensation of N-(chloroalkyl) naphthalenesultam derivatives with the appropriate amine in presence of a base, at reflux of DMF or THF. The yields were moderate (12-56%), except for the piperazine derivative 20 (85%). The affinity of the compounds for uptake site and 5-HT2, alpha 1, and D2 receptors was measured. Some compounds were studied in vivo by their potentiating effect of 5-HTP-induced symptomatology. The most potent and selective (uptake, 5-HT2 versus alpha 1, D2 sites) compounds contain a 3-[(4-piperidinyl)methyl]indole moiety. 5-Fluoro-3-[(4-piperidinyl)methyl]indole itself (compound 1) displayed a high affinity for the uptake site but was devoided of in vivo activity. N-Methylation of this compound abolished the affinity. In contrast N-substitution by a two-carbon chain linked to a naphthalenesultam or related heterocycle led to compounds exhibiting high affinity for the uptake site. One of them, 1-[2-[4-((5-fluoro-1H-indol-3-yl)methyl-1- piperidinyl]ethyl]-5,6-dihydro-1H,4H-1,2,5-thiadiazolo[4,3,2- ij]quinoline 2,2-dioxide (compound 24), was found as active as fluoxetine in vivo.