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1.
Front Immunol ; 13: 787713, 2022.
Article in English | MEDLINE | ID: mdl-35711429

ABSTRACT

Type 2 Innate lymphoid cells (ILC2s) are tissue-resident immune cells activated by epithelial-derived alarmins upon tissue damage. They regulate immunity against helminth parasites and allergies by expressing type 2 immune response cytokines including IL-9, known to be critical for inducing and potentiating the immune response in such context. Although ILC2s are reported to be the main source of IL-9 in mice during N. brasiliensis infection, the mechanisms that regulate the expression of IL-9 in these cells are yet to be described. Recent studies have shown that in addition to cytokines, multiple molecules can differentially modulate the functions of ILC2s in various contexts both in vitro and in vivo. Among these stimuli are lipid mediators and neuropeptides, which activate the PKA pathway and have been associated with the regulation of type 2 immune cytokines. In this work we found that ILC2s in mice infected with N. brasiliensis can be classified into different groups based on the expression of IL-9 and ST2. These distinct populations were distributed in the lung and the small intestine. Through the development of an in vitro culture system, we sought to determine the stimuli that regulate the expression of these markers in ILC2s. We identified the alarmin IL-33 as being a key player for increased IL-9 expression. Additionally, we found the PKA pathway to be a dual regulator of ILC2 cells, working synergistically with IL-33 to enhance IL-9 production and capable of modulating proliferation and the expression of ILC2 markers. These data provide further evidence of a high heterogeneity between ILC2 subsets in a context dependent manner and calls for careful consideration when choosing the markers to identify these cells in vivo. Distinguishing ILC2 subsets and dissecting their mechanisms of activation is critical for a deeper understanding of the biology of these cells, allowing their manipulation for therapeutic purposes.


Subject(s)
Immunity, Innate , Interleukin-33 , Animals , Cytokines , Interleukin-1 Receptor-Like 1 Protein/genetics , Interleukin-9/genetics , Lymphocytes , Mice
3.
J Ethnopharmacol ; 224: 563-578, 2018 Oct 05.
Article in English | MEDLINE | ID: mdl-29852265

ABSTRACT

ETHNOBOTANICAL RELEVANCE: Spondias mombin L. is a plant dispersed throughout the tropical regions of South America, Africa, and Asia, being found mainly in the North and Northeast of Brazil, where the leaves are used in preparations for neuropsychiatric disorders. Therefore, it is of great importance to carry out studies in different pharmacological models that can prove the traditional use of this plant species. MATERIALS AND METHODS: the hydroethanolic extract from S. mombin leaves (HELSm) was evaluated by oral administration (25 mg/kg) and by immersion (25 mg/l) in scototaxis test in zebrafish (Danio rerio). For this study, caffeine (100 mg/kg) and buspirone (25 mg/kg) were used as standard drugs. The antidepressant action of the HELSm was evaluated assessed in the novel tank diving test (NTDT). In this study, a group with 1% ethanol, one with unpredictable chronic mild stress (UCMS), and another with developmental, social isolation (DSI) were used as induction groups for depression-like behavior and fluoxetine (20 mg/kg) as a drug pattern. RESULTS: by the HPLC-UV fingerprint analysis, the HELSm presented several derivatives of polyphenolic compounds and flavonoids and identified ellagic acid and isoquercitrin, and by the gas-chromatographic, the majority of the identified compounds were fatty acids, esters, and alcohols. By immersion, the LC50 was 49.86 mg/l and by oral via the LD50 in 48 h, was 4.515 g/kg in zebrafish. For all spatiotemporal and behavioral variables (time spent, white compartment, latency, toggle, erratic swimming, freezing duration, thigmotaxis, and risk assessment), the treatment with HELSm produced a similar effect to buspirone and was significant when compared to the caffeine and control group (p < 0.01, Tukey-Kramer test). For all spatiotemporal and behavioral variables evaluated (time spent at the top of the apparatus, crossed quadrants, erratic swimming, and duration of freezing), treatment with HELSm produced a change in the depression-like behavior in the groups tested, with a similar effect to fluoxetine, both with a significant difference when compared to the control groups (p < 0.01). CONCLUSIONS: Our results suggest that the acute administration of the HELSm in the scototaxis and NTDT tests in a zebrafish model (Danio rerio) produced anxiolytic and antidepressant effects, devoid of hypnotic and sedative actions by immersion, and this action was improved when administered by oral via. Possibly, the presence of isoquercitrin in the leaves of Spondias mombin participates in the anxiolytic and antidepressant effects.


Subject(s)
Anacardiaceae , Anti-Anxiety Agents/pharmacology , Antidepressive Agents/pharmacology , Plant Extracts/pharmacology , Animals , Behavior, Animal/drug effects , Female , Male , Plant Leaves , Social Isolation , Stress, Psychological/drug therapy , Zebrafish/physiology
4.
Int J Antimicrob Agents ; 49(1): 88-92, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27939675

ABSTRACT

Acinetobacter baumannii is an emergent opportunistic bacterial pathogen responsible for recalcitrant infections owing to its high intrinsic tolerance to most antibiotics; therefore, suitable strategies to treat these infections are needed. One plausible approach is the repurposing of drugs that are already in use. Among them, anticancer drugs may be especially useful due their cytotoxic activities and ample similarities between bacterial infections and growing tumours. In this work, the effectiveness of four anticancer drugs on the growth of A. baumannii ATTC BAA-747 was evaluated, including the antimetabolite 5-fluorouracil and three DNA crosslinkers, namely cisplatin, mitomycin C (MMC) and merphalan. MMC was the most effective drug, having a minimum inhibitory concentration for 50% of growth in Luria-Bertani medium at ca. 7 µg/mL and completely inhibiting growth at 25 µg/mL. Hence, MMC was tested against a panel of 21 clinical isolates, including 18 multidrug-resistant (MDR) isolates, 3 of which were sensitive only to colistin. The minimum inhibitory concentrations and minimum bactericidal concentrations of MMC in all tested strains were found to be similar to those of A. baumannii ATCC BAA-747, and MMC also effectively killed stationary-phase, persister and biofilm cells. Moreover, MMC was able to increase survival of the insect larvae Galleria mellonella against an otherwise lethal A. baumannii infection from 0% to ≥53% for the antibiotic-sensitive A. baumannii ATCC BAA-747 strain and the MDR strains A560 and A578. Therefore, MMC is highly effective at killing the emergent opportunistic pathogen A. baumannii.


Subject(s)
Acinetobacter baumannii/drug effects , Anti-Bacterial Agents/pharmacology , Antibiotics, Antineoplastic/pharmacology , Drug Repositioning , Mitomycin/pharmacology , Acinetobacter Infections/drug therapy , Acinetobacter Infections/microbiology , Acinetobacter baumannii/growth & development , Animals , Anti-Bacterial Agents/administration & dosage , Antibiotics, Antineoplastic/administration & dosage , Cisplatin/pharmacology , Disease Models, Animal , Fluorouracil/pharmacology , Larva/microbiology , Lepidoptera/microbiology , Melphalan/pharmacology , Microbial Sensitivity Tests , Microbial Viability/drug effects , Mitomycin/administration & dosage , Survival Analysis , Treatment Outcome
5.
Biol Open ; 5(10): 1473-1484, 2016 Oct 15.
Article in English | MEDLINE | ID: mdl-27489304

ABSTRACT

Stress granules are cytoplasmic foci that directly respond to the protein synthesis status of the cell. Various environmental insults, such as oxidative stress or extreme heat, block protein synthesis; consequently, mRNA will stall in translation, and stress granules will immediately form and become enriched with mRNAs. P54 DEAD box RNA helicases are components of RNA granules such as P-bodies and stress granules. We studied the expression, in cytoplasmic foci, of both zebrafish P54 RNA helicases (P54a and P54b) during development and found that they are expressed in cytoplasmic granules under both normal conditions and stress conditions. In zebrafish embryos exposed to heat shock, some proportion of P54a and P54b helicases move to larger granules that exhibit the properties of genuine stress granules. Knockdown of P54a and/or P54b in zebrafish embryos produces developmental abnormalities restricted to the posterior trunk; further, these embryos do not form stress granules, and their survival upon exposure to heat-shock conditions is compromised. Our observations fit the model that cells lacking stress granules have no resilience or ability to recover once the stress has ended, indicating that stress granules play an essential role in the way organisms adapt to a changing environment.

6.
Drug Dev Res ; 75(2): 59-67, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24648132

ABSTRACT

In the present study, the mechanism of action of MMPP (1-(4-methoxy-2-methylphenyl) piperazine) in the acquisition (pretraining administration), formation (posttraining administration), and consolidation (pretest administration) of memory was assessed in the passive avoidance test using a short- and long-term memory protocol in mice. MMPP modified avoidance in the acquisition and formation of memory protocols but not in the consolidation protocol. Scopolamine (0.1 mg/kg i.p.), dizocilpine (0.003 mg/kg i.p.), and buspirone (0.1 mg/kg i.p.) completely inhibited MMPP-induced effects on memory acquisition and partially inhibited memory formation in the short-term but not long-term paradigm. This suggested that cholinergic, N-methyl-D-aspartate (NMDA) and 5-hydroxytryptamine-1A (5-HT1A ) receptors were implicated in the MMPP-induced improvements in memory. The sedative, anxiolytic, motor impairment, myorelaxant, and anticonvulsive (pentylenetetrazole-induced seizures) properties of MMPP were also assessed with the compound only showing a nondose-dependent myorelaxation. These results suggest that MMPP can enhance acquisition and formation, but not consolidation, of memory in short-term and long-term protocol via cholinergic, NMDA-glutamatergic, and 5-HT1A receptors.


Subject(s)
Avoidance Learning/drug effects , Memory, Long-Term/drug effects , Memory, Short-Term/drug effects , Nootropic Agents/pharmacology , Piperazines/pharmacology , Receptor, Serotonin, 5-HT1A/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Animals , Avoidance Learning/physiology , Behavior, Animal/drug effects , Dose-Response Relationship, Drug , Male , Memory, Long-Term/physiology , Memory, Short-Term/physiology , Mice, Inbred ICR , Nootropic Agents/administration & dosage , Piperazines/administration & dosage , Rotarod Performance Test
7.
J Ethnopharmacol ; 119(1): 47-52, 2008 Sep 02.
Article in English | MEDLINE | ID: mdl-18582555

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: The decoction of dried fruits of Ternstroemia pringlei (Rose) Standl. (Theaceae), commonly known as "Flor de Tila", is used in the Mexican traditional medicine to diminish insomnia and fear. AIM OF THE STUDY: To examine the sedative effects of the dried fruits of Ternstroemia pringlei and investigate a possible synergistic pharmacodynamic interaction between the sedative effect of aqueous extract of this plant and six central nervous system (CNS) depressant drugs. MATERIALS AND METHODS: The sedative effect was performed using the exploratory cylinder test in ICR mice. The extracts and drugs were intraperitoneally administered 30 min before testing in different doses, with exception of ethanol and buspirone which were administered 5 and 20 min before testing, respectively. An isobolographic analysis was used to characterize the interaction between Ternstroemia pringlei extract and six CNS depressant drugs. RESULTS: The intraperitoneal administration of the hexane, dichloromethane, methanol and aqueous extracts of Ternstroemia pringlei showed a dose-dependent sedative effect. Ternstroemia pringlei aqueous extract combined with buspirone, diazepam, diphenhydramine, haloperidol or pentobarbital exerted a super-additive (synergistic) sedative interaction. Whereas the combination Ternstroemia pringlei extract plus ethanol resulted in a sub-additive (attenuate) sedative interaction. CONCLUSIONS: These findings are in agreement with the traditional use of Ternstroemia pringlei in the treatment of insomnia, however it is a plant that interacts in a complex form with CNS depressant drugs. It may represent an advertence on the use of this plant concomitantly with other neuroactive drugs.


Subject(s)
Central Nervous System Depressants/pharmacology , Herb-Drug Interactions , Plant Extracts/pharmacology , Theaceae/chemistry , Animals , Central Nervous System Depressants/administration & dosage , Dose-Response Relationship, Drug , Drug Synergism , Exploratory Behavior/drug effects , Fruit , Injections, Intraperitoneal , Male , Medicine, Traditional , Mexico , Mice , Mice, Inbred ICR , Plant Extracts/administration & dosage , Solvents/chemistry
8.
Eukaryot Cell ; 6(4): 710-20, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17277172

ABSTRACT

Polyketide synthases (PKSs) and/or nonribosomal peptide synthetases (NRPSs) are central components of secondary metabolism in bacteria, plants, and fungi. In filamentous fungi, diverse PKSs and NRPSs participate in the biosynthesis of secondary metabolites such as pigments, antibiotics, siderophores, and mycotoxins. However, many secondary metabolites as well as the enzymes involved in their production are yet to be discovered. Both PKSs and NRPSs require activation by enzyme members of the 4'-phosphopantetheinyl transferase (PPTase) family. Here, we report the isolation and characterization of Aspergillus nidulans strains carrying conditional (cfwA2) and null (DeltacfwA) mutant alleles of the cfwA gene, encoding an essential PPTase. We identify the polyketides shamixanthone, emericellin, and dehydroaustinol as well as the sterols ergosterol, peroxiergosterol, and cerevisterol in extracts from A. nidulans large-scale cultures. The PPTase CfwA/NpgA was required for the production of these polyketide compounds but dispensable for ergosterol and cerevisterol and for fatty acid biosynthesis. The asexual sporulation defects of cfwA, DeltafluG, and DeltatmpA mutants were not rescued by the cfwA-dependent compounds identified here. However, a cfwA2 mutation enhanced the sporulation defects of both DeltatmpA and DeltafluG single mutants, suggesting that unidentified CfwA-dependent PKSs and/or NRPSs are involved in the production of hitherto-unknown compounds required for sporulation. Our results expand the number of known and predicted secondary metabolites requiring CfwA/NpgA for their biosynthesis and, together with the phylogenetic analysis of fungal PPTases, suggest that a single PPTase is responsible for the activation of all PKSs and NRPSs in A. nidulans.


Subject(s)
Aspergillus nidulans/enzymology , Bacterial Proteins/metabolism , Reproduction, Asexual/physiology , Transferases (Other Substituted Phosphate Groups)/metabolism , Alleles , Aspergillus nidulans/cytology , Aspergillus nidulans/growth & development , Bacterial Proteins/chemistry , Biological Factors/chemistry , Ergosterol/analogs & derivatives , Ergosterol/chemistry , Fermentation , Genes, Fungal , Lysine/biosynthesis , Mutation/genetics , Phylogeny , Pigmentation , Protein Structure, Tertiary , Siderophores/biosynthesis , Spores, Fungal/metabolism , Transferases (Other Substituted Phosphate Groups)/chemistry
9.
Ginecol. obstet. Méx ; 69(6): 218-226, jun. 2001. ilus
Article in Spanish | LILACS | ID: lil-309712

ABSTRACT

El conocimiento en la regulación de las funciones del ovario se ha extendido del concepto clásico de la regulación endocrina por hormonas sexuales y gonadotropinas al conocimiento de regulación intraovárica, por medio de factores parácrinos y autócrinos. El crecimiento folicular y la esteroidogénesis es regulada principalmente por las gonadotropinas (hormona folículo estimulante, FSH; y la hormona luteinizante, LH) y los esteroides. Por otra parte, últimamente han aumentado las evidencias que revelan que los factores de crecimiento intraováricos juegan un papel importante en la modulación de los efectos de las gonadotropinas en las funciones del ovario.


Subject(s)
ErbB Receptors , Polycystic Ovary Syndrome/physiopathology , Transforming Growth Factor alpha , Apoptosis , Ovarian Follicle/physiopathology
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