Abstract Simulating a bacterial-induced pulpitis environment in vitro may contribute to exploring mechanisms and bioactive molecules to counteract these adverse effects. Objective To investigate the chronic exposure of human dental pulp cells (HDPCs) to lipopolysaccharides (LPS) aiming to establish a cell culture protocol to simulate the impaired odontogenic potential under pulpitis conditions. Methodology HDPCs were isolated from four healthy molars of different donors and seeded in culture plates in a growth medium. After 24 h, the medium was changed to an odontogenic differentiation medium (DM) supplemented or not with E. coli LPS (0 - control, 0.1, 1, or 10 µg/mL) (n=8). The medium was renewed every two days for up to seven days, then replaced with LPS-free DM for up to 21 days. The activation of NF-κB and F-actin expression were assessed (immunofluorescence) after one and seven days. On day 7, cells were evaluated for both the gene expression (RT-qPCR) of odontogenic markers (COL1A1, ALPL, DSPP, and DMP1) and cytokines (TNF, IL1B, IL8, and IL6) and the production of reactive nitrogen (Griess) and oxygen species (Carboxy-H2DCFDA). Cell viability (alamarBlue) was evaluated weekly, and mineralization was assessed (Alizarin Red) at 14 and 21 days. Data were analyzed with ANOVA and post-hoc tests (α=5%). Results After one and seven days of exposure to LPS, NF-κB was activated in a dose-dependent fashion. LPS at 1 and 10 µg/mL concentrations down-regulated the gene expression of odontogenic markers and up-regulated cytokines. LPS at 10 µg/mL increased both the production of reactive nitrogen and oxygen species. LPS decreased cell viability seven days after the end of exposure. LPS at 1 and 10 µg/mL decreased hDPCs mineralization in a dose-dependent fashion. Conclusion The exposure to 10 µg/mL LPS for seven days creates an inflammatory environment that is able to impair by more than half the odontogenic potential of HDPCs in vitro, simulating a pulpitis-like condition. bacterialinduced bacterial induced effects (HDPCs (LPS conditions 2 h (DM E 0 ( control 01 0.1 µgmL µg mL n=8. n8 n n=8 . 8 (n=8) LPSfree free NFκB NF κB Factin F actin immunofluorescence (immunofluorescence 7 RTqPCR RT qPCR (RT-qPCR COL1A1, COL1A1 COLA COL A (COL1A1 ALPL DSPP DMP1 DMP TNF, TNF (TNF IL1B ILB IL B IL8 IL6 Griess (Griess CarboxyH2DCFDA. CarboxyH2DCFDA CarboxyHDCFDA Carboxy H2DCFDA H DCFDA (Carboxy-H2DCFDA) alamarBlue (alamarBlue weekly Alizarin Red posthoc post hoc α=5%. α5 α α=5% 5 (α=5%) dosedependent dose dependent fashion downregulated down regulated upregulated pulpitislike like condition 0. n= (n=8 COL1A (COL1A CarboxyH HDCFDA (Carboxy-H2DCFDA α=5 (α=5% (n= α= (α=5 (n (α= (α

Formigas cortadoras de folhas são consideradas pragas para a agricultura devido à grande quantidade de material vegetal utilizado por elas para cultivar um fungo simbionte que lhes serve de alimento e enzimas. O mutualismo entre o fungo e as formigas é um ponto a ser explorado quando se considera sua possível aplicação em métodos alternativos para o controle desses insetos. Sabendo-se que algumas plantas são naturalmente resistentes aos insetos fitófagos, alguns produtos naturais (metabólitos secundários) devem ser avaliados em relação às suas propriedades inseticidas e/ou fungicidas. Neste trabalho foram isoladas oito cumarinas de quatro espécies de plantas e o efeito no desenvolvimento do fungo simbionte das formigas cortadeiras Atta sexdens foi determinado. Com exceção da clausarina, todas as outras cumarinas foram inibitórias de 64 µg mL-1 à 80 µg mL-1 sendo que a xantiletina inibiu o fungo na concentração de 25 µg mL-1.

Leaf-cutting ants are known to be a serious pest for agriculture due to the high amounts of vegetal matter from crops used by them in order to cultivate a symbiotic fungus on which they rely for food and enzymes. The mutualism between the fungus and the ants is a point to be explored when alternative methods of control are being thought of. Considering that some plants are naturally resistant to phytophagous insects, some natural products (secondary metabolites) should be evaluated with respect to their insecticide and/or fungicide properties. In this paper we isolated eight coumarins from four different plant species and we determined their effect on the development of the symbiotic fungus of the leaf-cutting ant Atta sexdens. With the exception of clausarin, all the other coumarins were inhibitory from 64 µg mL-1 through 80 µg mL-1 and xanthyletin inhibited the fungus at 25 µg mL-1

Da casca do caule de Picramnia teapensis Tul. foram isolados dois novos benzoatos triterpênicos, o 3alfa,7beta-dibenzoato do ácido lup-20(29)-en-28-óico e o 7beta-benzoato do ácido 3alfa-hidroxi-lup-20(29)-en-28-óico. A elucidação estrutural desses compostos foi fundamentada na análise dos dados espectroscópicos. Outros compostos conhecidos, beta-sitosterol, estigmasterol, lupeol e epilupeol, foram identificados em mistura por CG-EM. Nenhum dos triterpenos benzoilados mostrou efeito inibitório no crescimento in-vitro do Leucoagaricus gongylophorus (Fisher), também citado como Leucocoprinus gongylophorus (Heim), syn Rozites gongylophora (Möller), o fungo simbionte cultivado pelas formigas cortadeiras de folhas Atta sexdens L.

Two new benzoic acid esters of triterpene alcohols [lup-20(29)-en-28-oic acid 3alpha,7beta-dibenzoate and 3alpha-hydroxy-lup-20(29)-en-28-oic acid 7beta-benzoate] were isolated from the stem bark of Picramnia teapensis Tul. The structures of these compounds were established on the basis of spectral analyses. Other known compounds, beta-sitosterol, estigmasterol, lupeol and epilupeol, were identified in mixture by GC-MS. The triterpene esters have not shown in-vitro inhibitory effect on the growth of Leucoagaricus gongylophorus (Fisher), referred also as Leucocoprinus gongylophorus (Heim), syn Rozites gongylophora (Möller), the symbiotic fungus cultivated by the leaf-cutting ant Atta sexdens L.

O fungo simbionte Leucoagaricus gongylophorus (Möller) Singer, sin. de Rozites gongylophora Möller, cultivado pela formiga cortadeira Atta sexdens L. teve seu desenvolvimento fortemente inibido por frações obtidas das folhas de gergelim, Sesamum indicum L. (Pedaliaceae). Total inibição foi observada na concentração de 2,5 mg/ml, sendo verificada inibição de 50% com algumas frações na concentração de 1,25 mg/ml. A análise cromatográfica do extrato hexânico revelou a ocorrência de uma mistura de ácidos graxos, onde os componentes majoritários foram os ácidos tetradecanóico, hexadecanóico, octadecanóico, icosanóico, docosanóico e 9,12,15 octadecatrienóico. A separação desses compostos durante as várias etapas do fracionamento resultou em perda ou diminuição da atividade inibitória sobre o fungo, indicando que a inibição observada pode ser consequência da ação conjunta de alguns dos compostos presentes nas folhas e não de uma única substância.

The symbiotic fungus Leucoagaricus gongylophorus (Möller) Singer (syn. Rozites gongylophora Möller) cultivated by the leaf-cutting ant Atta sexdens L. had its development strongly inhibited by crude extracts obtained from leaves of sesame, Sesamum indicum L. (Pedaliaceae). With most of the fractions from these extracts total inhibition was observed at 2.5 mg/ml, whereas inhibition of 50% was observed with some fractions at 1.25 mg/ml. Chromatographic analysis of the hexane extract showed that it was composed by a mixture of fatty acids, of which tetradecanoic, hexadecanoic, octadecanoic, icosanoic, docosanoic and 9,12,15 octadecatrienoic acids were the major components. The separation of these compounds during the different steps of purification resulted in no or lower inhibitory effect for most of these fractions, indicating that the inhibitory activity observed could be due to the joint action of these compounds present in the leaf tissue, rather than to the action of a single substance.