A concise formation of N-substituted 3,4-diarylpyrroles - synthesis and cytotoxic activity.

International audienceA short synthesis of N-substituted 3,4-diarylpyrroles by condensation of a phenacyl halide with a primary amine and a phenylacetaldehyde is reported. The key step is an intramolecular cyclization of an in situ generated enamine onto a ketone. Using differently substituted aromatic reactants and N-(3-aminopropyl)azatricyclodecane as the amine component, the preparation of analogs of the cytotoxic marine alkaloid halitulin could be achieved. The cytotoxicity of some of the compounds obtained by this method was studied, and one of them proved to be a very potent derivative, acting at a nanomolar concentration, in a caspase-independent cell death mechanism

Synthesis and biological evaluation of C-13′ substituted 7′-homo-anhydrovinblastine derivatives

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Overexpression of the natural tetrapeptide acetyl-N-ser-asp-lys-pro derived from thymosin beta 4 in neoplastic diseases

International audienceThe natural tetrapeptide acetyl-ser-asp-lys-pro (AcSDKP) is formed in vivo by enzymatic cleavage of the N terminus of thymosin beta4 by prolyl oligopeptidase (POP). Recently, AcSDKP was shown to promote angiogenesis. Because of the critical role of neovascularization in cancer development, the levels of AcSDKP and POP activity in a number of different malignant tissues were investigated. Our studies revealed that AcSDKP levels were markedly elevated in neoplastic diseases including hematologic malignancies and solid neoplasms. Consistent with this finding, the enhanced activity of POP was also detected in all analyzed specimens of cancer tissues. Both these novel findings are in concert with the previously reported overexpression of thymosin beta4 in a large variety of malignant tumors and with its potential role in cancerogenesis. The physiological relevance of these findings awaits further studies; however, our first results strongly suggest a key role for AcSDKP in the pathogenesis of cancer

In Vitro and In Vivo Properties of Ellagic Acid in Malaria Treatment▿

Malaria is one of the most significant causes of infectious disease in the world. The search for new antimalarial chemotherapies has become increasingly urgent due to the parasites’ resistance to current drugs. Ellagic acid is a polyphenol found in various plant products. In this study, antimalarial properties of ellagic acid were explored. The results obtained have shown high activity in vitro against all Plasmodium falciparum strains whatever their levels of chloroquine and mefloquine resistance (50% inhibitory concentrations ranging from 105 to 330 nM). Ellagic acid was also active in vivo against Plamodium vinckei petteri in suppressive, curative, and prophylactic murine tests, without any toxicity (50% effective dose by the intraperitoneal route inferior to 1 mg/kg/day). The study of the point of action of its antimalarial activity in the erythrocytic cycle of Plasmodium falciparum demonstrated that it occurred at the mature trophozoite and young schizont stages. Moreover, ellagic acid has been shown to potentiate the activity of current antimalarial drugs such as chloroquine, mefloquine, artesunate, and atovaquone. This study also proved the antioxidant activity of ellagic acid and, in contrast, the inhibitory effect of the antioxidant compound N-acetyl-l-cysteine on its antimalarial efficacy. The possible mechanisms of action of ellagic acid on P. falciparum are discussed in light of the results. Ellagic acid has in vivo activity against plasmodia, but modification of the compound could lead to improved pharmacological properties, principally for the oral route

A New Series of Succinimido-ferrociphenols and Related Heterocyclic Species Induce Strong Antiproliferative Effects, Especially against Ovarian Cancer Cells Resistant to Cisplatin

Ferrociphenols are known to display anticancer properties by original mechanisms dependent on redox properties and generation of active metabolites such as quinone methides. Recent studies have highlighted the positive impact of oxidative stress on chemosensitivity and prognosis of ovarian cancer patients. Ovarian adenocarcinomas are shown to be an excellent model for defining the impact of selected ferrociphenols as new therapeutic drugs for such cancers. This work describes the syntheses and preliminary mechanistic research of unprecedented multitargeting heterocyclic ferrociphenols bearing either a succinimidyl or phthalimidyl group that show exceptional antiproliferative behavior against epithelial ovarian cancer cells resistant to cisplatin. Owing to the failure of the present pharmaceutical options, such as carboplatin a metallodrug based on Pt coordination chemistry, these species may help to overcome the problem of lethal resistance. Currently, ferrociphenolic entities generally operate via apoptotic and senescence pathways. We present here our first results in this new cyclic-imide series

N-myristoyltransferases inhibitory activity of ellagitannins from Terminalia bentzoe (L.) L. f. subsp. bentzoe.

N-myristoylation (Myr) is an eukaryotic N-terminal co- or post-translational protein modification in which the enzyme N-myristoyltransferase (NMT) transfers a fatty acid (C14:0) to the N-terminal glycine residues of several cellular key proteins. Depending on the cellular context, NMT may serve as a molecular target in anticancer or anti-infectious therapy, and drugs that inhibit this enzyme may be useful in the treatment of cancer or infectious diseases. As part of an on-going project to identify natural Homo sapiens N-myristoyltransferase 1 inhibitors (HsNMT1), two ellagitannins, punicalagin (1) and isoterchebulin (2), along with eschweilenol C (3) and ellagic acid (4) were isolated from the bark of Terminalia bentzoe (L.) L. f. subsp. bentzoe. Their structures were determined by means of spectroscopic analyses and comparison with literature data. Punicalagin (1) and isoterchebulin (2) showed significant inhibitory activity towards HsNMT1, and also against Plasmodium falciparum NMT (PfNMT) both in vitro and in cellulo, opening alternative paths for new NMT inhibitors development. This is the first report identifying natural products from a botanical source as inhibitors of HsNMT and PfNMT

Bronchopulmonary infection-colonization patterns in Spanish cystic fibrosis patients: Results from a national multicenter study

Background: Clinical and demographical knowledge on Spanish cystic fibrosis (CF) patients is incomplete as no national registry exists. CF-microbiology has not been studied at national level. The results of the first Spanish multicenter study on CF microbiology are presented.Methods: 24 CF-Units for adult (n = 12) and pediatric (n = 12) patients from 17 hospitals provided sputa and clinical data from 15 consecutive patients. Cultures and susceptibility testing were performed. Colonization impact on pulmonary function was assessed.Results: 341 patients [mean (SD) age 21 (11) years, 180 >= 18 years, mean (SD) FEV1 = 68 (25)%] were included. Pseudomonas aeruginosa was reported as chronic, intermittent or absent in 46%, 22% and 32% of patients, respectively. The annual prevalence was 62%. Positive P. aeruginosa and methicillin-resistant Staphylococcus aureus cultures were significantly associated with lower FEV1 (p = 18 years, mean (SD) FEV1 = 68 (25)%] were included. Pseudomonas aeruginosa was reported as chronic, intermittent or absent in 46%, 22% and 32% of patients, respectively. The annual prevalence was 62%. Positive P. aeruginosa and methicillin-resistant Staphylococcus aureus cultures were significantly associated with lower FEV1 (

mTOR inhibition via displacement of phosphatidic acid induces enhanced cytotoxicity specifically in cancer cells

International audienceThe mTOR is a central regulator of cell growth and is highly activated in cancer cells to allow rapid tumor growth. The use of mTOR inhibitors as anticancer therapy has been approved for some types of tumors, albeit with modest results. We recently reported the synthesis of ICSN3250, a halitulin analogue with enhanced cytotoxicity. We report here that ICSN3250 is a specific mTOR inhibitor that operates through a mechanism distinct from those described for previous mTOR inhibitors. ICSN3250 competed with and displaced phosphatidic acid from the FRB domain in mTOR, thus preventing mTOR activation and leading to cytotoxicity. Docking and molecular dynamics simulations evidenced not only the high conformational plasticity of the FRB domain, but also the specific interactions of both ICSN3250 and phosphatidic acid with the FRB domain in mTOR. Furthermore, ICSN3250 toxicity was shown to act specifically in cancer cells, as noncancer cells showed up to 100-fold less sensitivity to ICSN3250, in contrast to other mTOR inhibitors that did not show selectivity. Thus, our results define ICSN3250 as a new class of mTOR inhibitors that specifically targets cancer cells.Significance: ICSN3250 defines a new class of mTORC1 inhibitors that displaces phosphatidic acid at the FRB domain of mTOR, inducing cell death specifically in cancer cells but not in noncancer cells