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1.
Front Microbiol ; 15: 1309160, 2024.
Article de Anglais | MEDLINE | ID: mdl-38680913

RÉSUMÉ

Introduction and objective: p62 is a human multifunctional adaptor protein involved in key cellular processes such as tissue homeostasis, inflammation, and cancer. It acts as a negative regulator of inflammasome complexes. It may thus be considered a good candidate for therapeutic use in inflammatory bowel diseases (IBD), such as colitis. Probiotics, including recombinant probiotic strains producing or delivering therapeutic biomolecules to the host mucosal surfaces, could help prevent and mitigate chronic intestinal inflammation. The objective of the present study was to combine the intrinsic immunomodulatory properties of the probiotic Lactococcus lactis NCDO2118 with its ability to deliver health-promoting molecules to enhance its protective and preventive effects in the context of ulcerative colitis (UC). Material and methods: This study was realized in vivo in which mice were supplemented with the recombinant strain. The intestinal barrier function was analyzed by monitoring permeability, secretory IgA total levels, mucin expression, and tight junction genes. Its integrity was evaluated by histological analyses. Regarding inflammation, colonic cytokine levels, myeloperoxidase (MPO), and expression of key genes were monitored. The intestinal microbiota composition was investigated using 16S rRNA Gene Sequencing. Results and discussion: No protective effect of L. lactis NCDO2118 pExu:p62 was observed regarding mice clinical parameters compared to the L. lactis NCDO2118 pExu: empty. However, the recombinant strain, expressing p62, increased the goblet cell counts, upregulated Muc2 gene expression in the colon, and downregulated pro-inflammatory cytokines Tnf and Ifng when compared to L. lactis NCDO2118 pExu: empty and inflamed groups. This recombinant strain also decreased colonic MPO activity. No difference in the intestinal microbiota was observed between all treatments. Altogether, our results show that recombinant L. lactis NCDO2118 delivering p62 protein protected the intestinal mucosa and mitigated inflammatory damages caused by dextran sodium sulfate (DSS). We thus suggest that p62 may constitute part of a therapeutic approach targeting inflammation.

2.
Probiotics Antimicrob Proteins ; 16(1): 275-292, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-36652108

RÉSUMÉ

Mucositis is a high-incidence side effect in cancer patients undergoing chemotherapy. Next-generation probiotics are emerging as new therapeutic tools for managing various disorders. Studies have demonstrated the potential of Akkermansia muciniphila to increase the efficiency of anticancer treatment and to mitigate mucositis. Due to the beneficial effect of A. muciniphila on the host, we evaluated the dose-response, the microorganism viability, and the treatment protocol of A. muciniphila BAA-835 in a murine model of chemotherapy-induced mucositis. Female Balb/c mice were divided into groups that received either sterile 0.9% saline or A. muciniphila by gavage. Mucositis was induced using a single intraperitoneal injection of 5-fluorouracil. The animals were euthanized three days after the induction of mucositis, and tissue and blood were collected for analysis. Prevention of weight loss and small intestine shortening and reduction of neutrophil and eosinophil influx were observed when animals were pretreated with viable A. muciniphila at 1010 colony-forming units per mL (CFU/mL). The A. muciniphila improved mucosal damage by preserving tissue architecture and increasing villus height and goblet cell number. It also improved the integrity of the epithelial barrier, decreasing intestinal permeability and bacterial translocation. In addition, the treatment prevented the expansion of Enterobacteriaceae. The immunological parameters were also improved by decreasing the expression of pro-inflammatory cytokines (IL6, IL1ß, and TNF) and increasing IL10. In conclusion, pretreatment with 1010 CFU/mL of viable A. muciniphila effectively controlled inflammation, protected the intestinal mucosa and the epithelial barrier, and prevented Enterobacteriaceae expansion in treated mice.


Sujet(s)
Antinéoplasiques , Inflammation muqueuse , Humains , Souris , Femelle , Animaux , Inflammation muqueuse/induit chimiquement , Inflammation muqueuse/traitement médicamenteux , Inflammation muqueuse/métabolisme , Cytokines/métabolisme , Muqueuse intestinale/métabolisme , Antinéoplasiques/pharmacologie , Akkermansia (genre)
3.
Article de Anglais | MEDLINE | ID: mdl-37097372

RÉSUMÉ

Next-generation microorganisms have recently gained prominence in the scientific community, mainly due to their probiotic and postbiotic potentials. However, there are few studies that investigate these potentials in food allergy models. Therefore, the present study was designed to evaluate the probiotic potential of Akkermansia muciniphila BAA-835 in an ovalbumin food allergy (OVA) model and also analyse possible postbiotic potential. To access the probiotic potential, clinical, immunological, microbiological, and histological parameters were evaluated. In addition, the postbiotic potential was also evaluated by immunological parameters. Treatment with viable A. muciniphila was able to mitigate weight loss and serum levels of IgE and IgG1 anti-OVA in allergic mice. In addition, the ability of the bacteria to reduce the injury of the proximal jejunum, the eosinophil and neutrophil influx, and the levels of eotaxin-1, CXCL1/KC, IL4, IL6, IL9, IL13, IL17, and TNF, was clear. Furthermore, A. muciniphila was able to attenuate dysbiotic signs of food allergy by mitigating Staphylococcus levels and yeast frequency in the gut microbiota. In addition, the administration of the inactivated bacteria attenuated the levels of IgE anti-OVA and eosinophils, indicating its postbiotic effect. Our data demonstrate for the first time that the oral administration of viable and inactivated A. muciniphila BAA-835 promotes a systemic immunomodulatory protective effect in an in vivo model of food allergy to ovalbumin, which suggests its probiotic and postbiotic properties.

4.
Probiotics Antimicrob Proteins ; 15(5): 1180-1192, 2023 10.
Article de Anglais | MEDLINE | ID: mdl-35907169

RÉSUMÉ

Functional foods containing probiotics are generally administered as dairy products. Non-dairy beverages are another possibility, but probiotic functionality must be confirmed in such vehicles. In the present study, a craft wheat beer brewed with the probiotic yeast Saccharomyces cerevisiae UFMG A-905 (905) was evaluated in a murine model of Salmonella Typhimurium infection. Unfiltered or filtered beer brewed with 905, a commercial wheat beer used as a negative control, or saline were administered orally to mice before and during oral S. Typhimurium challenge. High fecal levels of yeast were only counted in mice treated with the unfiltered 905 beer, which also had reduced mortality and body weight loss due to S. Typhimurium infection. Increased levels of intestinal IgA, translocation to liver and spleen, liver and intestinal lesions, pro-inflammatory cytokines in liver and ileum, and hepatic and intestinal myeloperoxidase and eosinophilic peroxidase activities were observed in animals infected with S. Typhimurium. All these parameters were reduced by the treatment with unfiltered 905 beer. In conclusion, the results show that a craft wheat beer brewed with S. cerevisiae UFMG A-905 maintained the probiotic properties of this yeast when administered orally to mice challenged with S. Typhimurium.


Sujet(s)
Probiotiques , Salmonelloses , Animaux , Souris , Saccharomyces cerevisiae , Salmonella typhimurium , Triticum , Bière
5.
Life Sci ; 289: 120243, 2022 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-34922941

RÉSUMÉ

Intestinal mucositis (IM) is a critical side-effect associated with antineoplastic therapy. Treatment available is only palliative and often not effective. However, alternative therapeutic strategies, such as probiotics, have attracted significant attention due to their immune-modulatory action in several diseases. Thus, the present study aims to elucidate the therapeutic potential of the probiotic strain Bifidobacterium longum 51A in a murine model of mucositis induced by irinotecan. Due to the scarcity of studies on dose-response and viability (probiotic vs paraprobiotic), we first evaluated which dose and cell viability would be most effective in treating mucositis. In this study, the oral pretreatment with viable B. longum 51A at a concentration of 1 × 109 CFU/mL reduced the daily disease activity index (p < 0.01), protected the intestinal architecture, preserved the length of the intestine (p < 0.05), and reduced intestinal permeability (p < 0.01), inflammation, and oxidative damage (p < 0.01) induced by irinotecan. Also, treatment with B. longum 51A increased the production of secretory immunoglobulin A (p < 0.05) in the intestinal fluid of mice with mucositis. Furthermore, B. longum 51A reversed the mucositis-induced increase in Enterobacteriaceae bacterial group in the gut (p < 0.01). In conclusion, these results showed that oral administration of B. longum 51A protects mice against intestinal damage caused by irinotecan, suggesting its use as a potential probiotic in therapy during mucositis.


Sujet(s)
Bifidobacterium longum , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Maladies intestinales , Irinotécan/effets indésirables , Inflammation muqueuse , Probiotiques/pharmacologie , Animaux , Femelle , Maladies intestinales/induit chimiquement , Maladies intestinales/microbiologie , Maladies intestinales/thérapie , Irinotécan/pharmacologie , Souris , Souris de lignée BALB C , Inflammation muqueuse/induit chimiquement , Inflammation muqueuse/microbiologie , Inflammation muqueuse/thérapie
6.
Curr Neuropharmacol ; 20(3): 510-523, 2022 Mar 04.
Article de Anglais | MEDLINE | ID: mdl-34279203

RÉSUMÉ

Nicotine induces long-term changes in the neural activity of the mesocorticolimbic reward pathway structures. The mechanisms involved in this process have not been fully characterized. The hypothesis discussed here proposed that epigenetic regulation participates in the installation of persistent adaptations and long-lasting synaptic plasticity generated by nicotine action on the mesolimbic dopamine neurons of zebrafish. The epigenetic mechanisms induced by nicotine entail histone and DNA chemical modifications, which have been described to lead to changes in gene expression. Among the enzymes that catalyze epigenetic chemical modifications, histone deacetylases (HDACs) remove acetyl groups from histones, thereby facilitating DNA relaxation and making DNA more accessible to gene transcription. DNA methylation, which is dependent on DNA methyltransferase (DNMTs) activity, inhibits gene expression by recruiting several methyl binding proteins that prevent RNA polymerase binding to DNA. In zebrafish, phenylbutyrate (PhB), an HDAC inhibitor, abolishes nicotine rewarding properties together with a series of typical reward-associated behaviors. Furthermore, PhB and nicotine alter long- and short-term object recognition memory in zebrafish, respectively. Regarding DNA methylation effects, a methyl group donor L-methionine (L-met) was found to dramatically reduce nicotine-induced conditioned place preference (CPP) in zebrafish. Simultaneous treatment with DNMT inhibitor 5-aza-2'-deoxycytidine (AZA) was found to reverse the L-met effect on nicotine-induced CPP as well as nicotine reward-specific effects on genetic expression in zebrafish. Therefore, pharmacological interventions that modulate epigenetic regulation of gene expression should be considered as a potential therapeutic method to treat nicotine addiction.


Sujet(s)
Nicotine , Danio zébré , Animaux , Épigenèse génétique , Inhibiteurs de désacétylase d'histone/pharmacologie , Nicotine/pharmacologie , Récompense , Danio zébré/génétique
7.
Rev. bras. ciênc. mov ; 28(2): 142-148, abr.-jun. 2020. tab
Article de Portugais | LILACS | ID: biblio-1127744

RÉSUMÉ

A prescrição de exercícios para o ganho de força e potência muscular é utilizado com o objetivo de ajudar na reabilitação de lesões musculares e para o aprimoramento físico nas práticas esportivas. Dentre as técnicas que são apontadas como possíveis condutas que poderiam auxiliar no fortalecimento muscular e potência destaca-se a Liberação Miofascial. Deste m o do, o estudo buscou analisar e comparar um programa de treinamento para ganho de potência muscular com fortalecimento muscular resistido isolado e os resultados de sua combinação com a Liberação Miofascial. Trata-se de um estudo quantitativo, transversal, analítico, de caráter experimental, comparativo, controlado e randomizado. A amostra foi composta por 11 mulheres com idade de 18 a 40 anos subdivididas em dois grupos de intervenção. As intervenções ocorerram 3 vezes por semana durante 4 semanas. Os membros do Grupo controle realizaram apenas o fortalecimento muscular com exercício de agachamento a partir de 0 º de flexão de joelhos até o limite de 90º de flexão e retornando ao grau 0. As voluntárias do Grupo Liberação Miofascial associado ao treino de força inicialmente foram submetidas a intervenções de Liberação Miofascial dos músculos quadríceps bilateralmente e posteriormente ao treino de fortalecimento muscular descrito no grupo controle. Foram avaliadas as variáveis distância do salto vertical e carga suportada em 1 Repetição Máxima. A estatística inferencial utilizada foi através do t este T de Student emparelhado para verificar a diferença entre as médias do antes e depois dos tratamentos em cada grupo. Para verificar as diferenças em relação às técnicas utilizadas em grupos diferentes foi realizado o teste T de Student não compartilhado. Os resultados demonstraram não haver diferença estatisticamente significante entre os grupos no que se refere a carga máxima suportada em 1 Repetição Máxima (p=0,484), mesmo sendo essa diferença numericamente de 3,31kg a mais de ganho para o Grupo que utilizou a Liberação Miofascial associada ao treino de força, e não foi encontrada diferença significativa (p=0,068) entre a distância de salto vertical nos grupos, apesar desta distânicia ser 4,35 cm maior também no grupo Liberação Miofascial associada ao treino de força. Foi possível demonstrar, desta form a, que a liberação miofascial não otimiza o ganho da potencia muscular associado ao exercício resistido . Desta forma, através dos resultados deste estudo, não é possível recomendar a utilização da LM como um recurso para ser utilizado pré treino com objetivo de ganho de potência muscular...(AU)


The prescription of exercises to gain muscle strength and power is used to help in the rehabilitation of muscle injuries and for physical improvement in sport practices. Among the techniques that are pointed as possible ways that could help in muscle strengthening and power, Myofascial Release stands out. Thus, the study sought to analyze and compare a training program for muscle power gain with isolated resistance muscle strengthening and the results of its combination with myofascial release. It is a quantitative, cross-sectional, analytical, experimental, comparative, controlled and randomized study. Our sample consisted of 11 women aged 18 to 40 years old, subdivided into two interventio n gro ups. Th e interventions occurred 3 times a week for 4 weeks. Control Group members only perform muscle strengthening with squats from 0º of knee flexion up to the limit of 90º of flexion and return of grade 0. As volunteers of the Myofascial Release Group associated with strength training, t hey were subm it ted t o Myofascial Release of the quadriceps muscles bilaterally and after the muscle st rengt hening t raining described in the control group. The variables vertical jump distance and load supported in 1 Maximum Repetition were evaluated. The inferential statistics used was through the paired Student's T test to verify the difference between the means of before and after treatments in each group. To verify the differences in relation to the techniques used in different groups, the Student's t-test was not shared. T here was n o statistically significant difference between the groups regarding the maximum load supported in 1 Maximum Repeat (p=0.484), even though this difference was numerically 3 .3 1kg m o re gain fo r t he Myofascial Release Group.No significant difference (p=0.068) was found either between t he v ertical jump distance, which was 4.35 cm higher ­ also in the Myofascial Release group. Thus, it was demonstrated that myofascial release does not optimize the gain in muscle power associat ed with resistance exercises. Thus, through the results of this study, it is not possible to recommend the use of SCI as a resource to be used pre-training in order to gain muscle power...(AU)


Sujet(s)
Humains , Femelle , Adolescent , Adulte , Réadaptation , Femmes , Exercice physique , Puissance , Groupes témoins , Manipulations de l'appareil locomoteur , Muscle quadriceps fémoral , Force musculaire , Entraînement en résistance , Sports , Thérapeutique , Bénévoles , Muscles
8.
J Comp Neurol ; 528(12): 2000-2020, 2020 08.
Article de Anglais | MEDLINE | ID: mdl-31997350

RÉSUMÉ

Injured retinas in mammals do not regenerate and heal with loss of function. The adult retina of zebrafish self-repairs after damage by activating cell-intrinsic mechanisms, which are regulated by extrinsic signal interactions. Among relevant regulatory extrinsic systems, purinergic signaling regulates progenitor proliferation during retinogenesis and regeneration and glia proliferation in proliferative retinopathies. ATP-activated P2X7 (P2RX7) and adenosine (P1R) receptors are involved in the progression of almost all retinopathies leading to blindness. Here, we examined P2RX7 and P1R participation in the retina regenerative response induced by photoreceptor damage caused by a specific dose of CoCl2 . First, we found that treatment of uninjured retinas with a potent agonist of P2RX7 (BzATP) provoked photoreceptor damage and mitotic activation of multipotent progenitors. In CoCl2 -injured retinas, blockade of endogenous extracellular ATP activity on P2RX7 caused further neurodegeneration, Müller cell gliosis, progenitor proliferation, and microglia reactivity. P2RX7 inhibition in injured retinas also increased the expression of lin28a and tnfα genes, which are related to multipotent progenitor proliferation. Levels of hif1α, vegf3r, and vegfaa mRNA were enhanced by blockade of P2RX7 immediately after injury, indicating hypoxic like damage and endothelial cell growth and proliferation. Complete depletion of extracellular nucleotides with an apyrase treatment strongly potentiated cell death and progenitor proliferation induced with CoCl2 . Blockade of adenosine P1 and A2A receptors (A2A R) had deleterious effects and deregulated normal timing for progenitor and precursor cell proliferation following photoreceptor damage. ATP via P2RX7 and adenosine via A2A R are survival extracellular signals key for retina regeneration in zebrafish.


Sujet(s)
Régénération nerveuse/physiologie , Neurones/anatomopathologie , Cellules photoréceptrices de vertébré/métabolisme , Récepteur A2A à l'adénosine/métabolisme , Récepteurs purinergiques P2X7/métabolisme , Animaux , Mort cellulaire/physiologie , Cobalt/toxicité , Dégénérescence nerveuse/induit chimiquement , Neurones/effets des médicaments et des substances chimiques , Neurones/métabolisme , Cellules photoréceptrices de vertébré/effets des médicaments et des substances chimiques , Cellules photoréceptrices de vertébré/anatomopathologie , Danio zébré
9.
Front Microbiol ; 8: 2424, 2017.
Article de Anglais | MEDLINE | ID: mdl-29270163

RÉSUMÉ

The sfk1 (suppressor of four kinase) gene has been mainly studied in Saccharomyces cerevisiae, where it was shown to be involved in growth and thermal stress resistance. This gene is widely conserved within the phylum Ascomycota. Despite this, to date sfk1 has not been studied in any filamentous fungus. Previously, we found that the orthologous of sfk1 was differentially expressed in a strain of Penicillium roqueforti with an altered phenotype. In this work, we have performed a functional characterization of this gene by using RNAi-silencing technology. The silencing of sfk1 in P. roqueforti resulted in decreased apical growth and the promotion of conidial germination, but interesting, it had no effect on conidiation. In addition, the attenuation of the sfk1 expression sensitized the fungus to osmotic stress, but not to thermal stress. RNA-mediated gene-silencing of sfk1 also affected cell wall integrity in the fungus. Finally, the silencing of sfk1 depleted the production of the main secondary metabolites of P. roqueforti, namely roquefortine C, andrastin A, and mycophenolic acid. To the best of our knowledge this is the first study of the sfk1 gene in filamentous fungi.

10.
Purinergic Signal ; 13(4): 443-465, 2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-28710541

RÉSUMÉ

Damage in fish activates retina repair that restores sight. The purinergic signalling system serves multiple homeostatic functions and has been implicated in cell cycle control of progenitor cells in the developing retina. We examined whether changes in the expression of purinergic molecules were instrumental in the proliferative phase after injury of adult zebrafish retinas with ouabain. P2RY1 messenger RNA (mRNA) increased early after injury and showed maximal levels at the time of peak progenitor cell proliferation. Extracellular nucleotides, mainly ADP, regulate P2RY1 transcriptional and protein expression. The injury-induced upregulation of P2RY1 is mediated by an autoregulated mechanism. After injury, the transcriptional expression of ecto-nucleotidases and ecto-ATPases also increased and ecto-ATPase activity inhibitors decreased Müller glia-derived progenitor cell amplification. Inhibition of P2RY1 endogenous activation prevented progenitor cell proliferation at two intervals after injury: one in which progenitor Müller glia mitotically activates and the second one in which Müller glia-derived progenitor cells amplify. ADPßS induced the expression of lin28a and ascl1a genes in mature regions of uninjured retinas. The expression of these genes, which regulate multipotent Müller glia reprogramming, was significantly inhibited by blocking the endogenous activation of P2RY1 early after injury. We consistently observed that the number of glial fibrillary acidic protein-BrdU-positive Müller cells after injury was larger in the absence than in the presence of the P2RY1 antagonist. Ecto-ATPase activity inhibitors or P2RY1-specific antagonists did not modify apoptotic cell death at the time of peak progenitor cell proliferation. The results suggested that ouabain injury upregulates specific purinergic signals which stimulates multipotent progenitor cell response.


Sujet(s)
Régulation de l'expression des gènes/physiologie , Régénération nerveuse/physiologie , Cellules souches pluripotentes/physiologie , Récepteurs purinergiques P2Y1/métabolisme , Rétine/physiologie , Animaux , Mitose , Cellules souches neurales , Neurogenèse/physiologie , Rétine/cytologie , Transduction du signal/physiologie , Régulation positive , Danio zébré
11.
Front Microbiol ; 8: 813, 2017.
Article de Anglais | MEDLINE | ID: mdl-28529508

RÉSUMÉ

Penicillium roqueforti is a filamentous fungus involved in the ripening of several kinds of blue cheeses. In addition, this fungus produces several secondary metabolites, including the meroterpenoid compound andrastin A, a promising antitumoral compound. However, to date the genomic cluster responsible for the biosynthesis of this compound in P. roqueforti has not been described. In this work, we have sequenced and annotated a genomic region of approximately 29.4 kbp (named the adr gene cluster) that is involved in the biosynthesis of andrastin A in P. roqueforti. This region contains ten genes, named adrA, adrC, adrD, adrE, adrF, adrG, adrH, adrI, adrJ and adrK. Interestingly, the adrB gene previously found in the adr cluster from P. chrysogenum, was found as a residual pseudogene in the adr cluster from P. roqueforti. RNA-mediated gene silencing of each of the ten genes resulted in significant reductions in andrastin A production, confirming that all of them are involved in the biosynthesis of this compound. Of particular interest was the adrC gene, encoding for a major facilitator superfamily transporter. According to our results, this gene is required for the production of andrastin A but does not have any role in its secretion to the extracellular medium. The identification of the adr cluster in P. roqueforti will be important to understand the molecular basis of the production of andrastin A, and for the obtainment of strains of P. roqueforti overproducing andrastin A that might be of interest for the cheese industry.

12.
Front Microbiol ; 7: 1518, 2016.
Article de Anglais | MEDLINE | ID: mdl-27790186

RÉSUMÉ

Termites are considered one of the most efficient decomposers of lignocelluloses on Earth due to their ability to produce, along with its microbial symbionts, a repertoire of carbohydrate-active enzymes (CAZymes). Recently, a set of Pro-oxidant, Antioxidant, and Detoxification enzymes (PAD) were also correlated with the metabolism of carbohydrates and lignin in termites. The lower termite Coptotermes gestroi is considered the main urban pest in Brazil, causing damage to wood constructions. Recently, analysis of the enzymatic repertoire of C. gestroi unveiled the presence of different CAZymes. Because the gene profile of CAZy/PAD enzymes endogenously synthesized by C. gestroi and also by their symbiotic protists remains unclear, the aim of this study was to explore the eukaryotic repertoire of these enzymes in worker and soldier castes of C. gestroi. Our findings showed that worker and soldier castes present similar repertoires of CAZy/PAD enzymes, and also confirmed that endo-glucanases (GH9) and beta-glucosidases (GH1) were the most important glycoside hydrolase families related to lignocellulose degradation in both castes. Classical cellulases such as exo-glucanases (GH7) and endo-glucanases (GH5 and GH45), as well as classical xylanases (GH10 and GH11), were found in both castes only taxonomically related to protists, highlighting the importance of symbiosis in C. gestroi. Moreover, our analysis revealed the presence of Auxiliary Activity enzyme families (AAs), which could be related to lignin modifications in termite digestomes. In conclusion, this report expanded the knowledge on genes and proteins related to CAZy/PAD enzymes from worker and soldier castes of lower termites, revealing new potential enzyme candidates for second-generation biofuel processes.

13.
PLoS One ; 11(1): e0147047, 2016.
Article de Anglais | MEDLINE | ID: mdl-26751579

RÉSUMÉ

The filamentous fungus Penicillium roqueforti is widely known as the ripening agent of blue-veined cheeses. Additionally, this fungus is able to produce several secondary metabolites, including the meroterpenoid compound mycophenolic acid (MPA). Cheeses ripened with P. roqueforti are usually contaminated with MPA. On the other hand, MPA is a commercially valuable immunosuppressant. However, to date the molecular basis of the production of MPA by P. roqueforti is still unknown. Using a bioinformatic approach, we have identified a genomic region of approximately 24.4 kbp containing a seven-gene cluster that may be involved in the MPA biosynthesis in P. roqueforti. Gene silencing of each of these seven genes (named mpaA, mpaB, mpaC, mpaDE, mpaF, mpaG and mpaH) resulted in dramatic reductions in MPA production, confirming that all of these genes are involved in the biosynthesis of the compound. Interestingly, the mpaF gene, originally described in P. brevicompactum as a MPA self-resistance gene, also exerts the same function in P. roqueforti, suggesting that this gene has a dual function in MPA metabolism. The knowledge of the biosynthetic pathway of MPA in P. roqueforti will be important for the future control of MPA contamination in cheeses and the improvement of MPA production for commercial purposes.


Sujet(s)
Fromage/microbiologie , Microbiologie alimentaire , Famille multigénique , Acide mycophénolique/biosynthèse , Penicillium/génétique , Voies de biosynthèse , Biologie informatique , Extinction de l'expression des gènes , Cadres ouverts de lecture , Plasmides , Interférence par ARN , RT-PCR
14.
J Pediatr Adolesc Gynecol ; 29(3): 304-11, 2016 Jun.
Article de Anglais | MEDLINE | ID: mdl-26620384

RÉSUMÉ

STUDY OBJECTIVE: To compare maternal and newborn pregnancy outcomes from adolescents and mature women. DESIGN, SETTING, AND PARTICIPANTS: A cross-sectional study was carried out in a public hospital, including women with singleton pregnancies, who were classified according to their age, as follows: group 1: younger than 16 years old (n = 37), group 2: 16-19 years old (n = 288), and group 3: 20-34 years old (n = 632). INTERVENTIONS AND MAIN OUTCOME MEASURES: Information on clinical characteristics, gynecological and obstetric history, pregnancy complications, and perinatal outcomes was obtained through interviews and from clinical records. RESULTS: Thirty-four percent of deliveries were from adolescents. Mature women were more likely to have prepregnancy overweight or obesity than adolescents (odds ratio [OR] = 2.4, 95% confidence interval [CI], 1.7-3.4). The frequency of maternal complications during pregnancy or delivery was not different between groups. Birth asphyxia was more frequent in group 2 (P = .02). Women with inadequate prenatal care had an increased risk of preterm deliveries (OR = 1.64; 95% CI, 1.06-2.54) and of having newborns with low birth weight (OR = 2.02; 95% CI, 1.22-3.35). Weight of newborns from noncomplicated pregnancies was lower in group 1 (P = .02), after adjustment for prepregnancy body mass index, gestational weight gain, preterm delivery, and newborn sex. CONCLUSION: The frequency of maternal and perinatal complications was similar in adolescents and mature women. Birth weight was decreased in noncomplicated pregnancies of adolescents younger than 16 years of age. Adequate prenatal care might be helpful in prevention of some adverse perinatal outcomes.


Sujet(s)
Facteurs âges , Hôpitaux publics/statistiques et données numériques , Issue de la grossesse , Adolescent , Adulte , Poids de naissance , Études transversales , Accouchement (procédure)/statistiques et données numériques , Femelle , Humains , Nourrisson à faible poids de naissance , Nouveau-né , Mexique/épidémiologie , Obésité/épidémiologie , Odds ratio , Surpoids/épidémiologie , Grossesse , Complications de la grossesse/épidémiologie , Naissance prématurée/épidémiologie , Prise en charge prénatale/statistiques et données numériques , Facteurs de risque , Prise de poids , Jeune adulte
15.
Front Microbiol ; 6: 903, 2015.
Article de Anglais | MEDLINE | ID: mdl-26441853

RÉSUMÉ

Natural product search is undergoing resurgence upon the discovery of a huge previously unknown potential for secondary metabolite (SM) production hidden in microbial genomes. This is also the case for filamentous fungi, since their genomes contain a high number of "orphan" SM gene clusters. Recent estimates indicate that only 5% of existing fungal species have been described, thus the potential for the discovery of novel metabolites in fungi is huge. In this context, fungi thriving in harsh environments are of particular interest since they are outstanding producers of unusual chemical structures. At present, there are around 16 genomes from extreme environment-isolated fungi in databases. In a preliminary analysis of three of these genomes we found that several of the predicted SM gene clusters are probably involved in the biosynthesis of compounds not yet described. Genome mining strategies allow the exploitation of the information in genome sequences for the discovery of new natural compounds. The synergy between genome mining strategies and the expected abundance of SMs in fungi from extreme environments is a promising path to discover new natural compounds as a source of medically useful drugs.

16.
PLoS One ; 10(3): e0120740, 2015.
Article de Anglais | MEDLINE | ID: mdl-25811807

RÉSUMÉ

Proteins containing Zn(II)(2)Cys(6) domains are exclusively found in fungi and yeasts. Genes encoding this class of proteins are broadly distributed in fungi, but few of them have been functionally characterized. In this work, we have characterized a gene from the filamentous fungus Penicillium roqueforti that encodes a Zn(II)(2)Cys(6) protein, whose function to date remains unknown. We have named this gene pcz1. We showed that the expression of pcz1 is negatively regulated in a P. roqueforti strain containing a dominant active Gαi protein, suggesting that pcz1 encodes a downstream effector that is negatively controlled by Gαi. More interestingly, the silencing of pcz1 in P. roqueforti using RNAi-silencing technology resulted in decreased apical growth, the promotion of conidial germination (even in the absence of a carbon source), and the strong repression of conidiation, concomitant with the downregulation of the genes of the central conidiation pathway brlA, abaA and wetA. A model for the participation of pcz1 in these physiological processes in P. roqueforti is proposed.


Sujet(s)
Protéines fongiques/génétique , Protéines fongiques/métabolisme , Penicillium/physiologie , Carbone/métabolisme , Protéines fongiques/composition chimique , Régulation de l'expression des gènes fongiques , Extinction de l'expression des gènes , Phénotype , Sous-unités de protéines , Interférence par ARN , Petit ARN interférent/génétique
17.
PLoS One ; 9(5): e98208, 2014.
Article de Anglais | MEDLINE | ID: mdl-24858105

RÉSUMÉ

Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules.


Sujet(s)
Carcinome épidermoïde/métabolisme , Contacts focaux/métabolisme , Régulation de l'expression des gènes tumoraux , Protéines tumorales/biosynthèse , Tumeurs expérimentales/métabolisme , Taline/biosynthèse , Tumeurs de la langue/métabolisme , Animaux , Carcinome épidermoïde/génétique , Carcinome épidermoïde/anatomopathologie , Mouvement cellulaire/génétique , Contacts focaux/génétique , Contacts focaux/anatomopathologie , Hétérogreffes , Humains , Mâle , Souris , Souris de lignée BALB C , Souris nude , Invasion tumorale , Protéines tumorales/génétique , Transplantation tumorale , Tumeurs expérimentales/génétique , Tumeurs expérimentales/anatomopathologie , Protéomique/méthodes , Taline/génétique , Tumeurs de la langue/génétique , Tumeurs de la langue/anatomopathologie , Régulation positive/génétique
18.
BMC Genomics ; 14: 91, 2013 Feb 11.
Article de Anglais | MEDLINE | ID: mdl-23394930

RÉSUMÉ

BACKGROUND: The ascomycete fungus Ceratocystis cacaofunesta is the causal agent of wilt disease in cacao, which results in significant economic losses in the affected producing areas. Despite the economic importance of the Ceratocystis complex of species, no genomic data are available for any of its members. Given that mitochondria play important roles in fungal virulence and the susceptibility/resistance of fungi to fungicides, we performed the first functional analysis of this organelle in Ceratocystis using integrated "omics" approaches. RESULTS: The C. cacaofunesta mitochondrial genome (mtDNA) consists of a single, 103,147-bp circular molecule, making this the second largest mtDNA among the Sordariomycetes. Bioinformatics analysis revealed the presence of 15 conserved genes and 37 intronic open reading frames in C. cacaofunesta mtDNA. Here, we predicted the mitochondrial proteome (mtProt) of C. cacaofunesta, which is comprised of 1,124 polypeptides - 52 proteins that are mitochondrially encoded and 1,072 that are nuclearly encoded. Transcriptome analysis revealed 33 probable novel genes. Comparisons among the Gene Ontology results of the predicted mtProt of C. cacaofunesta, Neurospora crassa and Saccharomyces cerevisiae revealed no significant differences. Moreover, C. cacaofunesta mitochondria were isolated, and the mtProt was subjected to mass spectrometric analysis. The experimental proteome validated 27% of the predicted mtProt. Our results confirmed the existence of 110 hypothetical proteins and 7 novel proteins of which 83 and 1, respectively, had putative mitochondrial localization. CONCLUSIONS: The present study provides the first partial genomic analysis of a species of the Ceratocystis genus and the first predicted mitochondrial protein inventory of a phytopathogenic fungus. In addition to the known mitochondrial role in pathogenicity, our results demonstrated that the global function analysis of this organelle is similar in pathogenic and non-pathogenic fungi, suggesting that its relevance in the lifestyle of these organisms should be based on a small number of specific proteins and/or with respect to differential gene regulation. In this regard, particular interest should be directed towards mitochondrial proteins with unknown function and the novel protein that might be specific to this species. Further functional characterization of these proteins could enhance our understanding of the role of mitochondria in phytopathogenicity.


Sujet(s)
Ascomycota/génétique , ADN mitochondrial/génétique , Génome mitochondrial , Protéines mitochondriales/génétique , Ascomycota/classification , Ascomycota/pathogénicité , Cacaoyer/génétique , Cacaoyer/microbiologie , Biologie informatique , Régulation de l'expression des gènes fongiques , Mitochondries/génétique , Mitochondries/métabolisme , Phylogenèse , Maladies des plantes/génétique , Maladies des plantes/microbiologie , Protéome/analyse , Protéome/génétique
19.
Psychopharmacology (Berl) ; 226(3): 551-60, 2013 Apr.
Article de Anglais | MEDLINE | ID: mdl-23192315

RÉSUMÉ

RATIONALE: Prior exposure to drugs of abuse may increase or decrease the reinforcing effects of the drug in later consumptions. Based on the initial locomotor activity (LA) response to an acute drug administration or to novelty in an open-field arena, animals can be classified as low or high LA responders (LR or HR). Few studies have used this classification with nicotine, and the results are controversial. Some authors suggested that nicotine can induce conditioned-place preference (CPP) following prior nicotine exposure, whereas others suggested that previous nicotine exposure extinguishes nicotine-CPP. OBJECTIVE: To explore if the administration of nicotine in a novel environment without explicit behavioral consequences to classify animals in low and high nicotine responders (LNR and HNR) could affect the establishment of nicotine CPP in male Sprague-Dawley rats. RESULTS: Prior exposure to a single dose of nicotine (0.4 mg/kg, subcutaneously) induced CPP in LNR rats after 14 days of conditioning (seven-trial) but not after two or eight conditioning days. In contrast, HNR rats did not show CPP under any condition. In addition, our results indicated that previous exposure to nicotine decreased its rewarding effects in eight conditioning days CPP (four-trial), which can be regularly established without prior exposure to nicotine. CONCLUSION: The results suggested that response to a single exposure to nicotine predicts the acquisition of nicotine preference in a 14-day conditioning protocol only for LNR rats. Thus, our findings demonstrated the relevance of using LNR and HNR classification when the individual susceptibility to nicotine preference is studied.


Sujet(s)
Conditionnement psychologique/effets des médicaments et des substances chimiques , Activité motrice/effets des médicaments et des substances chimiques , Nicotine/pharmacologie , Récompense , Animaux , Injections sous-cutanées , Mâle , Nicotine/administration et posologie , Rats , Rat Sprague-Dawley , 12476 , Facteurs temps
20.
PLoS One ; 7(9): e45929, 2012.
Article de Anglais | MEDLINE | ID: mdl-23029323

RÉSUMÉ

The widespread SCP/TAPS superfamily (SCP/Tpx-1/Ag5/PR-1/Sc7) has multiple biological functions, including roles in the immune response of plants and animals, development of male reproductive tract in mammals, venom activity in insects and reptiles and host invasion by parasitic worms. Plant Pathogenesis Related 1 (PR-1) proteins belong to this superfamily and have been characterized as markers of induced defense against pathogens. This work presents the characterization of eleven genes homologous to plant PR-1 genes, designated as MpPR-1, which were identified in the genome of Moniliophthora perniciosa, a basidiomycete fungus responsible for causing the devastating witches' broom disease in cacao. We describe gene structure, protein alignment and modeling analyses of the MpPR-1 family. Additionally, the expression profiles of MpPR-1 genes were assessed by qPCR in different stages throughout the fungal life cycle. A specific expression pattern was verified for each member of the MpPR-1 family in the conditions analyzed. Interestingly, some of them were highly and specifically expressed during the interaction of the fungus with cacao, suggesting a role for the MpPR-1 proteins in the infective process of this pathogen. Hypothetical functions assigned to members of the MpPR-1 family include neutralization of plant defenses, antimicrobial activity to avoid competitors and fruiting body physiology. This study provides strong evidence on the importance of PR-1-like genes for fungal virulence on plants.


Sujet(s)
Agaricales/génétique , Cacaoyer/génétique , Cacaoyer/microbiologie , Protéines fongiques/génétique , Maladies des plantes/microbiologie , Protéines végétales/génétique , Agaricales/composition chimique , Agaricales/physiologie , Séquence d'acides aminés , Cacaoyer/composition chimique , Protéines fongiques/composition chimique , Régulation de l'expression des gènes fongiques , Gènes fongiques , Gènes de plante , Interactions hôte-pathogène , Modèles moléculaires , Données de séquences moléculaires , Protéines végétales/composition chimique , Conformation des protéines
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