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International audience; Integrin targeted therapies by natural bioactive compounds have attracted attention in the field of oncology and cancer treatment. This study evaluates the potential of phenolic extract from the medicinal herb Ecballium elaterium L. seed oil (PEO) to inhibit the adhesion and migration of the highly invasive human fibrosarcoma cell line HT1080. At safe concentrations (up to 40 mg mL −1), results show that PEO dosedependently inhibits adhesion and migration of HT1080 to fibronectin (IC 50 = 18 mg mL −1) and fibrinogen (IC 50 = 12.86 mg mL −1). These observations were associated with the reduction of cell motility and migration velocity as revealed in the Boyden chamber and random motility using two-dimensional assays, respectively. Additional experiments using integrin blocking antibodies showed that PEO at the highest safe concentration (40 mg mL −1) competitively inhibited the attachment of HT1080 cell to anti-avb3 (>98%), anti-a5b1 (>86%), and to a lesser extent anti-a2 (>50%) immobilized antibodies, suggesting that avb3 and a5b1 integrins were selectively targeted by PEO. Moreover, PEO specifically targeted these integrins in human microvascular endothelial cells (HMEC-1) and dose-dependently blocked the in vitro tubulogenesis. In the CAM model, PEO inhibited the VEGF-induced neoangiogenesis confirming its antiangiogenic effect. Collectively, these results indicate that PEO holds promise for the development of natural integrin-targeted therapies against fibrosarcoma.

The venoms of Tunisian wildlife snakes are complex mixtures containing proteins/ peptides and non-protein molecules. Proteins and peptides are the most abundant compounds responsible for the biological effects of venoms. Snake venoms proteins have enzymatic or nonenzymatic activities, which are grouped into different families, including C-type lectin proteins, disintegrins (long, medium and short disintegrins), Kunitz-type serine protease inhibitors, natriuretic- like peptides, vascular endothelial growth factor-related proteins, L-amino acid oxidases, phospholipases A2 and serine proteinases. With technological advancements, the toxic effects of venoms were turned into potential benefits for clinical diagnosis, basic research and development of new research tools and drugs of potential clinical use. Our research team has shown that Macrovipera lebetina and Cerastes cerastes venom components of Tunisian wildlife snakes had great potential for the development of new drugs for the treatment of cancer, angiogenesis disorders or cardiovascular diseases. This review is an overview of snake venom proteins from Macrovipera lebetina and Cerastes cerastes and their biochemical, pharmacological and molecular characterization and their importance as protein resources with therapeutic potential.

Mint species (Lamiaceae family) have been used as traditional remedies for the treatment of several diseases. In this work, we aimed to characterize the biological activities of the total phenolic and flavonoid contents of Mentha pulegium L. extracts collected from two different regions of Tunisia. The highest amounts of total phenols (74.45 ± 0.01 mg GAE/g DW), flavonoids (28.87 ± 0.02 mg RE/g DW), and condensed tannins (4.35 ± 0.02 mg CE/g DW) were found in the Bizerte locality. Methanolic leaf extracts were subjected to HPLC-UV analysis in order to identify and quantify the phenolic composition. This technique allowed us to identify seven phenolic compounds: two phenolic acids and five flavonoid compounds, such as eriocitrin, hesperidin, narirutin, luteolin, and isorhoifolin, which were found in both extracts with significant differences between samples collected from the different regions (p < 0.05). Furthermore, our results showed that the methanolic extract from leaves collected from Bizerte had the highest antioxidant activities (DPPH IC50 value of 16.31 μg/mL and 570.08 μmol Fe2+/g, respectively). Both extracts showed high radical-scavenging activity as well as significant antimicrobial activity against eight tested bacteria. The highest antimicrobial activities were observed against Gram-positive bacteria with inhibition zone diameters and MIC values ranging between 19 and 32 mm and 40 and 160 µg/mL, respectively. Interestingly, at 10 μg/mL, the extract had a significant effect on cell proliferation of U87 human glioblastoma cells. These findings open perspectives for the use of Mentha pulegium L. extract in green pharmacy, alternative/complementary medicine, and natural preventive therapies for the development of effective antioxidant, antibacterial, and/or antitumoral drugs.

Hepatocellular carcinoma (HCC) is the most common primary liver cancer in adults, the fifth most common malignancy worldwide and the third leading cause of cancer related death. An alternative to the surgical treatments and drugs, such as sorafenib, commonly used in medicine is necessary to overcome this public health problem. In this study, we determine the anticancer effect on HCC of Moroccan cobra Naja haje venom and its fraction obtained by gel filtration chromatography against Huh7.5 cancer cell line. Cells were grown together with WI38 human fibroblast cells, LX2 human hepatic stellate cell line, and human endothelial cells (HUVEC) in MCTS (multi-cellular tumor spheroids) models. The hepatotoxicity of venom and its fractions were also evaluated using the normal hepatocytes cell line (Fa2N-4 cells). Our results showed that an anti HCC activity of Moroccan cobra Naja haje venom and, more specifically, the F7 fraction of gel filtration chromatography exhibited the greatest anti-hepatocellular carcinoma effect by decreasing the size of MCTS. This effect is associated with a low toxicity against normal hepatocytes. These results strongly suggest that the F7 fraction of Moroccan cobra Naja haje venom obtained by gel filtration chromatography possesses the ability to inhibit cancer cells proliferation. More research is needed to identify the specific molecule(s) responsible for the anticancer effect and investigate their mechanism of action.

Platelets have a well-established role in atherosclerosis and related diseases. Lebetins from the venom of Vipera lebetina, lacking the RGD sequence, emerged as a new family of platelet aggregation inhibitors. However, the interaction sites and precise mechanism between lebetin and its substrate remain unclear. Here, we successfully synthesized two peptide analogs, which differ only by one glycine residue at the N-terminus: lebetin 2α (sL2α residues) and lebetin 2β (sL2ββ residues) were produced in sufficient quantities for structural and functional studies. NMR structure determination showed that the sL2α peptide adopts a compact ring conformation stabilized by a disulfide bond, from which emerge one loop and two extended regions, the C- and N-termini. Interestingly, two RGD-like motifs were identified in the structure of the peptides, suggesting an anti-platelet aggregation effect of the two isoforms. Indeed, activity was demonstrated on human and rabbit platelet-rich plasma where sL2α and sL2β showed more potent inhibitory effect on platelet aggregation compared to the previously described native lebetin 1. Synthetic lebetin 2 peptides constitute promising candidates for drug design toward chimeric compounds with high anti-platelet and natriuretic effects. These findings contribute to a novel field of research triggering platelet activation and natriuretic action.

Natural polyphenols are widely reported to have a large range of pharmacological properties, especially antioxidant activities and free radical scavenging capacities. In this study, we investigate the effects of naringin, chlorogenic acid, and quercetin mixtures (NCQ) on renal fibrosis in streptozotocin (STZ)-induced diabetic aged rats and its underlying mechanisms for ten consecutive weeks. The oxidative defense system in the kidneys of treated rats was found to be improved. Several biomarkers were investigated including the blood urea nitrogen, creatinine, and uric acid. Moreover, antioxidant parameters were evaluated and we found that superoxide dismutase, catalase, glutathione peroxidase, Na+-K+-ATPase activities, the nitric oxide production, the protein carbonyl, the advanced oxidation protein products, lipid peroxidation, and reduced glutathione levels were all significantly balanced and close to control values. In addition, NCQ restored renal injuries and fibrosis as assessed by histological method and molecular biology investigation of the matrix metalloproteinase, the transforming growth factor-beta TGF-β, the tumor necrosis factor TNFα, and p53 expression. Our study proposes the NCQ combination as potential plant-derived bioactive compounds to prevent diabetic nephropathy.

The excessive production of inflammatory mediators results in an overactive immune response leading to the worsening of various human diseases. Thus, there is a still need to identify molecules able to regulate the inflammatory response. Lebecetin, a C-type lectin protein isolated from Macrovipera lebetina snake venom, was previously characterized as a platelet aggregation inhibitor and antitumor active biomolecule. In the present work, we investigated its effect on the production of some cytokines linked to inflammatory response and the underlying mechanisms in lipopolysaccharide (LPS)-induced THP1 macrophages. Interestingly, we found that lebecetin reduced the levels of the pro-inflammatory cytokines TNF-α, IL-6, and IL-8 while it partially increased LPS-induced secretion of the immunomodulatory cytokine IL-10. Furthermore, this modulatory effect was accompanied by decreased activation of ERK1/2, p38, AKT kinases and NF-κB along with reduced expression of αvβ3 integrin. Thus, this study highlights the promising role of lebecetin as a natural biomolecule that could manage the inflammatory response involved in the development and progression of inflammatory diseases.

International audience; Prostate cancer is the most highly diagnosed cancer in men worldwide. It is characterized by high proliferation, great invasion and metastatic potential. Sodium channel subtypes have been identified as highly expressed in different prostate cancer cell lines. In this study, we have screened the negatively charged fractions of Androctonus australis (Aa) scorpion venom to identify active peptides on DU145 prostate cancer cells proliferation. The most active compound was identified to be the sodium channel peptide AaHIV with an IC50 value of 15 μM. At this concentration, AaHIV had low effect on the adhesion of DU145 cells to fibronectin. When compared to other Na+ channel Aa toxins, AaHIV was found to be 2 times more active than AaHI and AaHII on DU145 cells proliferation and slightly less active than AaHII on their adhesion. The three peptides are inactive on DU145 cells migration. AaHIV was found to be 16 times more active than veratridine, asteroidal alkaloid from plants of the lily family widely used as a sodium channel activator. Electrophysiological experiments showed that the AaHIV toxin activates Nav1.6 channel, suggesting that this sodium channel subtype is implicated in the proliferation of DU145 prostate cancer cells.

International audience; Through the recent development of knowledge in biotechnology and bioinformatics, snake venoms are widely used to develop new drugs to treat diseases such as hypertension and cancer. We have previously reported that Lebetin 2 isolated from Macrovipera lebetina transmediterranea venom displays a potent anti-platelet activity and exerts a cardioprotective effect in ischemia-reperfusion (IR) injury model. Here, we report that Lebetin 2 possess an anti-tumor effect by targeting the integrin receptor function. It was thus able to inhibit both adhesion and migration of pheochromocytoma cells (PC12) and α1β1 integrin-expressing CHO cells (CHO-α1) to type I and IV collagens. Moreover, this peptide affects proliferation of PC12 cells by modulating AKT phosphorylation. Furthermore, Lebetin 2 exhibits a potent anti-angiogenic effect as assessed in vitro and ex vivo, using both the embryo chick chorioallantoic membrane model (CAM) and rat aortic ring assay. Interestingly, the interaction mode of Lebetin 2 with the integrin α1β1, assessed in silico, showed that the peptide represents a steric obstruction preventing the collagen from enforcing the interactions with the integrin.

Objective We synthesized new tamoxifen derivatives as anticancer drug candidates and elaborated on convection-enhanced delivery (CED) as a strategy for delivery. Methods To overcome the issue of their poor solubility, these ferrocenyl-tamoxifen derivatives were esterified and encapsulated into different nanocarriers, that is lipid (LNC) and polymeric nanocapsules (PNL-NC). We describe the chemistry, the encapsulation and the physicochemical characterization of these formulations. Key findings Starting compounds [phthalimido-ferrocidiphenol and succinimido-ferrocidiphenol], esterified prodrugs and their nanocapsules formulations were characterized. These drug candidates displayed a strong in vitro activity against breast and glioblastoma cancer cells. The ester prodrugs were toxic for glioblastoma cells (IC50 = 9.2 × 10−2 μm and 6.7 × 10−2 μm, respectively). The IC50 values for breast cancer cells were higher for these compounds. The encapsulation of the esterified compounds in LNCs (≈50 nm) or PCL-NCs (≈300 nm) did not prevent their efficacy on glioblastoma cells. These anticancer effects were due to both blockade in the S-phase of the cell cycle and apoptosis. Moreover, the tamoxifen derivatives-loaded nanocapsules induced no toxicity for healthy astrocytes and showed no haemolytic properties. Loaded Lipid Nanocapsules (LNCs) presented interesting profiles for the optimal delivery of active compounds. Conclusions Phthalimido- and Succinimido-esters represent an innovative approach to treat cancers with cerebral localizations such as glioblastoma or brain metastases from breast cancers.

Two series of 3,5-disubstituted isoxazoles (6a–e) and 1,4-disubstituted triazoles (8a–e) derivatives have been synthesized from tyrosol (1), a natural phenolic compound, detected in several natural sources such as olive oil, and well-known by its wide spectrum of biological activities. Copper-catalyzed microwave-assisted 1,3-dipolar cycloaddition reactions between tyrosol-alkyne derivative 2 and two series of aryl nitrile oxides (5a–e) and azides (7a-e) regiospecifically afforded 3,5-disubstituted isoxazoles (6a–e) and 1,4-triazole derivatives (8a–e), respectively in quantitative yields. Synthesized compounds were purified and characterized by spectroscopic means including 1D and 2D NMR techniques and HRMS analysis. The newly prepared hybrid molecules have been evaluated for their anticancer and hemolytic activities. Results showed that most derivatives displayed significant antiproliferative activity against human glioblastoma cancer cells (U87) in a dose-dependent manner. Compounds 6d (IC50 = 15.2 ± 1.0 μg/mL) and 8e (IC50 = 21.0 ± 0.9 μg/mL) exhibited more potent anticancer activity. Moreover, most derivatives displayed low hemolytic activity, even at higher concentrations which suggested that these classes of compounds are suitable candidates for further in vivo investigations. The obtained results allow us to consider the newly synthesized isoxazole- and triazole-linked tyrosol derivatives as promising scaffolds for the development of effective anticancer agents.

International audience; In the present study, the effect of Ecbalium elaterium seed oil on adhesion, migration and proliferation of human brain cancer cell line (U87) was determined. Treatment of U87 cell line with the seed oil resulted in strong inhibition of their adhesion to fibrinogen (Fg), fibronectin (Fn). It also reduced their migration and proliferation in a dose-dependent manner without being cytotoxic. Concomitantly, by using Matrigel™ assays, the oil significantly inhibited angiogenesis. The anti- tumor effect of the oil is specifically mediated by αvβ3 and α5β1 integrins. The presence of integrin antagonists in seed oil from E. elaterium could be used for the development of anticancer drugs with targeted "multi-modal" therapies combining anti-adhesif, antiproliferative, antimetastasic and anti-angiogenic, approaches.

International audience; the first scorpion peptide with dual disintegrin activity on α1β1 and αvβ3 integrins. Abstract: Scorpion peptides are well known for their pharmaceutical potential on different targets. These include mainly the ion channels which were found to be highly expressed in many diseases, including cancer, auto-immune pathologies and Alzheimer. So far, however, the disintegrin activity had only been characterized for snake venom molecules. Herein, we present the first short peptide, purified from the venom of Buthus occitanus tunetanus, (termed RK) able to inhibit the cell adhesion of Glioblastoma, Melanoma and Rat pheochromocytoma to different extracellular matrix (ECM) receptors. Anti-integrin antibody assay suggests that RK interacts with both α1β1 and αvβ3 with a more pronounced effect for the former. The examination of the primary structure of RK suggests the involvement of two motifs: KSS, analogue to KTS which was characterized for α1β1 Snake venom disintegrins, and ECD, analogue to RGD which was found to be active on αvβ3. To assess their roles in the disintegrin activity of RK, we conducted a computational analysis. The molecular docking study shows that RK involves mainly two segments to interact with the α1β1 integrin, but the peptide does not implicate the KSS motif in the interaction. The molecular modeling study, suggests the key contribution of the ECD segment in the interaction with αvβ3 integrin.

The decavanadate compound with inorganic cations, (NH4)4Li2V10O28.10H2O, was synthesized by slow evaporation from aqueous solution. It was characterized by Infrared (IR) spectroscopy, Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX) as well as thermal analysis such as Differential Scanning Calorimetry (DSC), differential thermal analysis (DTA) and thermogravimetry (TG). The formula unit consists of one decavanadate cluster [V10O28]6−, two lithium cations, four ammonium ions and ten water molecules. In the crystal, molecules are linked into a three-dimensional network by O-H…O and N-H…O hydrogen bonds. The prevalence of these intermolecular interactions was confirmed by an analysis of the Hirshfeld surface (HS) and fingerprint plots (FP). The relative contribution of different interactions to the HS indicates that the O…H/H…O and H…H contacts account 86.8% of the total HS area. In this study, the cytotoxic and the antiproliferative activities of (NH4)4Li2V10O28.10H2O on human cancer cells (U87, IGR39 and MDA-MB-231) were investigated. This compound demonstrated dose-dependent antiproliferative activity on U87, MDA-MB-231 and IGR39 with IC50 values of 2 µg/mL, 18 µg/mL and 12 µg /mL, respectively. These data provide evidence on the potential anticancer activity of (NH4)4Li2V10O28.10H2O.

In this study, we verify the possible activity of Artemisia herba-alba and A. campestris (Asteraceae) essential oil against the snake venoms. The leaves of A. campestris has been used in the folk medicine against snake moisture. The aerial part extracts of both plants have been tested for their action against snake venom. Interaction of A. campestris (E1) and A. herba alba (E2) essential oils with proteins extracted from snake venom has been tested. Lethality in mice, inflammation and cytotoxicity induced by Cerastes cerastes venoms were significantly inhibited by the mixture of different amounts of E1 and E2 and the venom. However, both extracts showed neutralization of the venoms hemolytic activity which is more important with E2. Chemical characterization of E1 and E2 revealed there is an important amount of polyphenols and tannins which are known by their bio-active effect. The result could lead as to think that these components have an action by inhibiting the toxicity of snake venoms in vitro. We can conclude therefore that the use of the essential oil from the two Artemisia species have a curative effect on the snake venom. These results confirmed the traditional use of A. campestris and we discovered a similar effect of A. herba-alba. No data have been reported till now about the essential oil curative effect of both species. © 2016 Friends Science Publishers

Fish protein hydrolysate was prepared from muscle of small red scorpionfish (Scorpaena notata) by treatment with a protease from the fungus Penicillium digitatum. Protein hydrolysate was found to strongly inhibit the angiotensin I converting enzyme and exhibited high antioxidative activity through 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay. After ultrafiltration, peptides were isolated by a two-step procedure: size exclusion chromatography on a Toyopearl HW-40 followed by reversed-phase high-performance liquid chromatography with a high purification yield of 2.5 mg of peptide per gram of initial protein. Two major peptides were then identified by nanoscale liquid chromatography coupled to tandem mass spectrometry (nano-LC-MS/MS), corresponding to the following sequences: Leu-Val-Thr-Gly-Asp-Asp-Lys-Thr-Asn-Leu-Lys (1,204.665 Da) and Asp-Thr-Gly-Ser-Asp-Lys-Lys-Gln-Leu (992.511 Da). These peptides, mainly composed of hydrophilic amino acids, showed high antioxidative and angiotensin I converting enzyme inhibitory activities. These data suggest that the two novel peptides isolated from the muscle hydrolysate of small red scorpionfish can be a beneficial ingredient for functional foods or pharmaceuticals against hypertension and oxidative stress.

International audience; We recently purified an heterodimeric phospholipase A2 named Sm-PLGV from the venom glands of scorpion Scorpio maurus containing a Long chain, a penta-peptide insertion, which is cut out during the maturation, followed by a short chain. Three recombinant forms of Sm-PLGV were produced in Escherichia coli: rPLA2(+5) containing the full-length sequence including the penta-peptide insert, rPLA2(-5) a fused continuous chain of the Long and the short chains without the penta-peptide and the Long chain alone without the short one. In this study, we showed that Sm-PLGV, rPLA2(+5) and rPLA2(-5) displayed more potent anti-angiogenic properties than the recombinant Long chain and the short chain obtained by chemical synthesis. These phospholipases A2 inhibited in a dose-dependent manner adhesion, migration and invasion of human microvascular endothelial cells through the alteration of α5β1 and αvβ3 integrins function. Using Matrigel™ and chick chorioallantoic membrane assays, we demonstrated that Sm-PLGV, rPLA2(+5) and rPLA2(-5) significantly inhibited both in vitro and in vivo angiogenesis. We also showed a clear dissociation of the anti-angiogenic effect of Sm-PLGV and its catalytic activity. This is the first study describing an anti-angiogenic effect for recombinant scorpion venom enzymes.

The aim of this study was to evaluate the antioxidant, the anti-inflammatory, and the antitumoral activities of the aqueous ethanolic extract fromPhoenix dactyliferaL. parthenocarpic dates. The antioxidant activity was carried using DPPH radical scavenging activity. The result showed that parthenocarpic dates had strongly scavenging activity on DPPH reaching 94% with an IC50value of 0.15 ± 0.011 mg/mL (p < 0.05). The anti-inflammatory potential was determined by the inhibitory effect of the aqueous ethanolic extract on phospholipase A2activity as well as on carrageenan-induced paw oedema in mice. Thein vitrostudy showed that the extract inhibited the phospholipase A2activity with an IC50value of 130 μg/mL and thein vivostudy showed a significantly decrease in the paw oedema after 1 h compared to the control group. Finally, the antiproliferative activity of the aqueous ethanolic extract was assessed by MTT test against MCF-7 and MDA-MB-231 cancer cell lines. This extract was effective in inhibiting MDA-MB-231 and MCF-7 cancer cells growth with IC50values of 8 and 18 mg/mL, respectively, after 72 h treatment. These results confirm the ethnopharmacological significance ofPhoenix dactyliferaL. parthenocarpic dates, which could add support for its pharmaceutical use.

Scorpion peptides are well known for their pharmaceutical potential on different targets. These include mainly the ion channels which were found to be highly expressed in many diseases, including cancer, auto-immune pathologies and Alzheimer. So far, however, the disintegrin activity had only been characterized for snake venom molecules. Herein, we present the first short peptide, purified from the venom of Buthus occitanus tunetanus, (termed RK) able to inhibit the cell adhesion of Glioblastoma, Melanoma and Rat pheochromocytoma to different extracellular matrix (ECM) receptors. Anti-integrin antibody assay suggests that RK interacts with both α

International audience; Voltage-gated potassium (Kv) channels are known to play a pivotal role in the progression of various cancer types and considered as new targets for designing anti-cancer therapy. However, the fact that many Kv channels are expressed in different cell lines makes it difficult to ascribe a functional role for a given Kv channel on a specific aspect of the tumorogenesis. In this work, we showed that although both Kv1.1 and Kv1.3 channels are expressed in U87 (glioblastoma), MDA-MB-231 (breast cancer) and LS174 (colon adenocarcinoma) cells, these respond differently to KAaH1 or KAaH2, two homologous Kv1 blockers from scorpion venom. KAaH1 is active on Kv1.1 and Kv1.3 and was found to inhibit migration and adhesion of U87 cells whereas KAaH2 which is slightly active only on Kv1.1 channel, inhibits their proliferation via the EGFR signaling pathway. The correlation between the electro-physiological activity of the scorpion peptides and their anti-migratory effects suggests the involvement of the Kv1.1 and Kv1.3 channels in the mobility of the three cancer cell lines. Our results showed that besides they can elucidate the implication of Kv1.1 and Kv1.3 channels in molecular mechanisms of neoplastic progression, KAaH1 and KAaH2 may be used as therapeutic tools against glioblastoma.

International audience; In a previous study, we purified Sm-PLGV an heterodimeric phospholipase A2, from the venom glands of the Tunisian scorpion Scorpio maurus. This enzyme contains a Long chain, a penta-peptide insertion, which is cut out during the maturation process, followed by a short chain. A disulfide bridge links the two chains. Three recombinant forms of this enzyme were produced in Escherichia coli: rPLA2(+5) with a penta-peptide insert, rPLA2(-5) without the penta-peptide, and the Long chain alone without the short one. In the present study, we showed that Sm-PLGV, rPLA2(+5) and rPLA2(-5) displayed more potent anti-angiogenic activity in vitro than the recombinant Long chain and the short one obtained by chemical synthesis. These phospholipases A2 inhibited in a dose-dependent manner adhesion, migration and invasion of Human Umbilical Vein Endothelial Cells. Using Matrigel™, we demonstrated that Sm-PLGV, rPLA2(+5) and rPLA2(-5) significantly inhibited tubulogensesis. We also showed a clear dissociation between the anti-angiogenic effect of Sm-PLGV and its catalytic activity.

In a previous study, we purified Sm-PLGV an heterodimeric phospholipase A

We recently purified an heterodimeric phospholipase A

Allium roseum L. (Alliaceae) endemic mediterranean specie was represented in the North Africa by 12 different taxa. In the present study, chemical composition, antiproliferative, antioxidant and antimicrobial activities of the essential oil extracted from A. roseum var. grandiflorum Briq. bulbs collected in the North of Tunisia were investigated. Chemical characterization has shown methyl methanethiosulfinate as major sulphurous compounds. A. roseum bulbs essential oil provides interesting antiproliferative activity against two human colonic adenocarcinoma HT29 and CACO2 cell lines in dose-dependent manner with a half-maximal inhibition (IC50) of 4.64 µg/mL and 8.22 µg/mL respectively. The antioxidant activity, as determined by FRAP assay, was 285 µmol equivalent Trolox/g of essential oil. The scavenging effect on DPPH radicals of essential oil was estimated as IC50 values at 156 µg/mL. The inhibition of superoxide anion production in a model of cancer cell lines was significant for both lines HT29 and CACO2 with IC50 of 20.25 µg/mL and 29.12 µg/mL respectively. Allium roseum essential oil exhibited antibacterial and antifungal activities with a high effectiveness against Candida albicans given by an MIC value of 0.019 mg/mL. This biological effect appears to be related mainly to the presence of organosulfur compounds.

International audience; Hard ticks (Acari: Ixodidae) are blood-sucking ectoparasites characterized by the extended period of their attachment to their host. To access their bloodmeal, ticks secrete saliva containing a range of molecules that target the host's inflammation, immune system, and hemostatic components. Some of these molecules reportedly possess antiangiogenic and antitumor properties. The present study describes our investigation, the first of its kind, of the antiangiogenic and antitumoral effects of the Hyalomma dromedarii Koch, 1844 (Acari: Ixodidae), salivary gland extract (SGE), which inhibited the adhesion and migration of Human Umbilical Vein Endothelial Cells (HUVECs) in a dose-dependent manner, as well as angiogenesis in the Chick Chorioallantoic Membrane model. Interestingly, H. dromedarii SGE exerted an antiproliferative effect on U87 glioblastoma cells and inhibited their adhesion and migration to fibrinogen. These results open up new possibilities for characterizing and developing new molecules involved in the key steps of tumor progression.

International audience; Snail secretion is currently revolutionizing the world of cosmetics and human skin care. The efficacy of snail secretion in wounds healing has been proven both in vitro and by clinical studies. However, the potential anti-tumor effect of snail secretion was poorly investigated. In this report, our in vitro study showed that Helix aspersa maxima species snail slime (SS) could not only treat melanogenesis but also endowed with anti-tumoral activity against human melanoma cells. Indeed, SS reduced melanin content and tyrosinase activity on B16F10 cells with IC50 values of 288 μg/mL and 286 μg/mL, respectively, without altering cell viability. This effect was also observed, at a lesser extent, on human melanoma IGR-39 and SK-MEL-28 cell lines. On another hand, SS specifically inhibited the viability of IGR-39 and SK-MEL-28 cells associated to an apoptotic effect highlighted by PARP cleavage. It is worth to note that SS did not affect the viability of B16F10 cells and non tumorigenic HaCaT cells. Interestingly, this extract was found to inhibit migration and invasion of both human melanoma cells through reducing the expression of Matrix metalloproteinase MMP2. Snail slime also exerted a high inhibitory effect on IGR-39 cell adhesion through blocking the function of α2β1 (45%), αvβ3 (38%) integrins and by reducing the expression levels of αv and β1 integrins. The presented results shed light on the potential anti-melanoma effect of SS and support its use against skin diseases.

International audience; Fish protein hydrolysate was prepared from muscle of small red scorpionfish (Scorpaena notata) by treatment with a protease from the fungus Penicillium digitatum. Protein hydrolysate was found to strongly inhibit the angiotensin I converting enzyme and exhibited high antioxidative activity through 1,1-diphenyl-2-picrylhydrazyl free radical scavenging assay. After ultrafiltration, peptides were isolated by a two-step procedure: size exclusion chromatography on a Toyopearl HW-40 followed by reversed-phase high-performance liquid chromatography with a high purification yield of 2.5 mg of peptide per gram of initial protein. Two major peptides were then identified by nanoscale liquid chromatography coupled to tandem mass spectrometry (nano-LC-MS/MS), corresponding to the following sequences: Leu-Val-Thr-Gly-Asp-Asp-Lys-Thr-Asn-Leu-Lys (1,204.665 Da) and Asp-Thr-Gly-Ser-Asp-Lys-Lys-Gln-Leu (992.511 Da). These peptides, mainly composed of hydrophilic amino acids, showed high antioxidative and angiotensin I converting enzyme inhibitory activities. These data suggest that the two novel peptides isolated from the muscle hydrolysate of small red scorpionfish can be a beneficial ingredient for functional foods or pharmaceuticals against hypertension and oxidative stress.

Angiogenesis is a cause of visual impairment and blindness in the wet form of age-related macular degeneration and in ischemic retinopathies. Current therapies include use of anti-VEGF agents to reduce choroidal neovascularization (CNV) and edema. These treatments are effective in most cases, but spontaneous or acquired resistance to anti-VEGF and possible adverse effects of long-term VEGF inhibition in the retina and choroid highlight a need for additional alternative therapies. Integrins αvβ3 and αvβ5, which regulate endothelial cell proliferation and stabilization, have been implicated in ocular angiogenesis. Lebecetin (LCT) is a 30-kDa heterodimeric C-type lectin that is isolated from Macrovipera lebetina venom and interacts with α5β1- and αv-containing integrins. We previously showed that LCT inhibits human brain microvascular endothelial cell adhesion, migration, proliferation, and tubulogenesis. To evaluate the inhibitory effect of LCT on ocular angiogenesis, we cultured aortic and choroidal explants in the presence of LCT and analyzed the effect of LCT on CNV in the mouse CNV model and on retinal neovascularization in the oxygen-induced retinopathy model. Our data demonstrate that a single injection of LCT efficiently reduced CNV and retinal neovascularization in these models.-Montassar, F., Darche, M., Blaizot, A., Augustin, S., Conart, J.-B., Millet, A., Elayeb, M., Sahel, J.-A., Reaux-Le Goazigo, A., Sennlaub, F., Marrakchi, N., Messadi, E., Guillonneau, X. Lebecetin, a C-type lectin, inhibits choroidal and retinal neovascularization.

// Florent Dufour 1, 2 , Thibault Rattier 1, 2 , Andrei Alexandru Constantinescu 1, 2 , Luciana Zischler 1, 2, 3 , Aymeric Morle 1, 2 , Hazem Ben Mabrouk 4 , Etienne Humblin 1, 2 , Guillaume Jacquemin 1, 2 , Eva Szegezdi 5 , Fabien Delacote 6 , Naziha Marrakchi 4 , Gilles Guichard 7 , Catherine Pellat-Deceunynck 8 , Pierre Vacher 9 , Patrick Legembre 10 , Carmen Garrido 1, 2, 11 , Olivier Micheau 1, 2, 11 1 INSERM, UMR866, « Equipe labellisee Ligue contre le Cancer » and Laboratoire d’Excellence LipSTIC, Dijon, France 2 Univ. Bourgogne Franche-Comte, Dijon, France 3 Pos-graduacao emCiencias da Saude, Escola de Medicina, Pontificia Univ. Catolica do Parana, Curitiba, Parana, Brazil 4 Laboratoire des Venins et Biomolecules Therapeutiques LR11IPT08, Institut Pasteur de Tunis, Tunis, Tunisia 5 Department of Biochemistry and National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland 6 Cellectis, Paris, France 7 Univ. de Bordeaux, CNRS, IPB, UMR 5248, CBMN, Institut Europeen de Chimie et de Biologie, Pessac, France 8 INSERM, UMR892, CNRS 6299, Universite de Nantes, Nantes, France 9 INSERM U1218, Univ. de Bordeaux, Institut Bergonie, Bordeaux, France 10 CLCC Eugene Marquis, INSERM ER440 Oncogenesis, Stress & Signaling, Rennes, France 11 Centre Georges-Francois Leclerc, Dijon, France Correspondence to: Micheau Olivier, email: olivier.micheau@inserm.fr Keywords: receptor, TRAIL, signaling, apoptosis, cancer Received: September 02, 2016 Accepted: November 30, 2016 Published: December 27, 2016 ABSTRACT TRAIL induces selective tumor cell death through TRAIL-R1 and TRAIL-R2. Despite the fact that these receptors share high structural homologies, induction of apoptosis upon ER stress, cell autonomous motility and invasion have solely been described to occur through TRAIL-R2. Using the TALEN gene-editing approach, we show that TRAIL-R1 can also induce apoptosis during unresolved unfolded protein response (UPR). Likewise, TRAIL-R1 was found to co-immunoprecipitate with FADD and caspase-8 during ER stress. Its deficiency conferred resistance to apoptosis induced by thaspigargin, tunicamycin or brefeldin A. Our data also demonstrate that tumor cell motility and invasion-induced by TRAIL-R2 is not cell autonomous but induced in a TRAIL-dependant manner. TRAIL-R1, on the other hand, is unable to trigger cell migration owing to its inability to induce an increase in calcium flux. Importantly, all the isogenic cell lines generated in this study revealed that apoptosis induced TRAIL is preferentially induced by TRAIL-R1. Taken together, our results provide novel insights into the physiological functions of TRAIL-R1 and TRAIL-R2 and suggest that targeting TRAIL-R1 for anticancer therapy is likely to be more appropriate owing to its lack of pro-motile signaling capability.

International audience; Cardiac ischemia is one of the leading causes of death worldwide. It is now well established that natriuretic peptides can attenuate the development of irreversible ischemic injury during myocardial infarction. Lebetin 2 (L2) is a new discovered peptide isolated from Macrovipera lebetina venom with structural similarity to B-type natriuretic peptide (BNP). Our objectives were to define the acute cardioprotective actions of L2 in isolated Langendorff-perfused rat hearts after regional or global ischemia-reperfusion (IR). We studied infarct size, left ventricular contractile recovery, survival protein kinases and mitochondrial permeability transition pore (mPTP) opening in injured myocardium. L2 dosage was determined by preliminary experiments at its ability to induce cyclic guanosine monophosphate (cGMP) release without changing hemodynamic effects in normoxic hearts. L2 was found to be as effective as BNP in reducing infarct size after the induction of either regional or global IR. Both peptides equally improved contractile recovery after regional IR, but only L2 increased coronary flow and reduced severe contractile dysfunction after global ischemia. Cardioprotection afforded by L2 was abolished after isatin or 5-hydroxydecanote pretreatment suggesting the involvement of natriuretic peptide receptors and mitochondrial KATP (mitoKATP) channels in the L2-induced effects. L2 also increased survival protein expression in the reperfused myocardium as evidenced by phosphorylation of signaling pathways PKCε/ERK/GSK3β and PI3K/Akt/eNOS. IR induced mitochondrial pore opening, but this effect was markedly prevented by L2 treatment. These data show that L2 has strong cardioprotective effect in acute ischemia through stimulation of natriuretic peptide receptors. These beneficial effects are mediated, at least in part, by mitoKATP channel opening and downstream activated survival kinases, thus delaying mPTP opening and improving IR-induced mitochondrial dysfunction.