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1.
Molecules ; 29(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474545

RESUMO

Sol g 2 is the major protein in Solenopsis geminata fire ant venom. It shares the highest sequence identity with Sol i 2 (S. invicta) and shares high structural homology with LmaPBP (pheromone-binding protein (PBP) from the cockroach Leucophaea maderae). We examined the specific Sol g 2 protein ligands from fire ant venom. The results revealed that the protein naturally formed complexes with hydrocarbons, including decane, undecane, dodecane, and tridecane, in aqueous venom solutions. Decane showed the highest affinity binding (Kd) with the recombinant Sol g 2.1 protein (rSol g 2.1). Surprisingly, the mixture of alkanes exhibited a higher binding affinity with the rSol g 2.1 protein compared to a single one, which is related to molecular docking simulations, revealing allosteric binding sites in the Sol g 2.1 protein model. In the trail-following bioassay, we observed that a mixture of the protein sol g 2.1 and hydrocarbons elicited S. geminata worker ants to follow trails for a longer time and distance compared to a mixture containing only hydrocarbons. This suggests that Sol g 2.1 protein may delay the evaporation of the hydrocarbons. Interestingly, the piperidine alkaloids extracted have the highest attraction to the ants. Therefore, the mixture of hydrocarbons and piperidines had a synergistic effect on the trail-following of ants when both were added to the protein.


Assuntos
Venenos de Formiga , Formigas , Animais , Proteínas de Transporte/metabolismo , 60601 , Feromônios/química , Ligantes , Simulação de Acoplamento Molecular , Formigas/química , Alcanos/metabolismo
2.
Sci Rep ; 13(1): 21119, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036575

RESUMO

Invasive ants pose a risk to human well-being and social/ecosystem stability. Linepithema humile Mayr is among the most damaging invasive ants worldwide. Most L. humile populations invade ports/wharfs isolated from surrounding landscapes, but unfortunately, a new population was discovered in an inland urban area (Nara Prefecture) of Japan in 2021. In this study, first, the supercolony type of the Nara L. humile population was identified via a hostility test, and then its distribution pattern was characterized. In aggression tests between L. humile from Nara and four supercolonies (haplotypes LH1, LH2, LH3, LH4), this ant showed extremely strong hostility against all supercolonies exept LH2, which was detected only in Japan in its introduced range. In Nara, L. humile was abundant in and around the urban river. Simulations revealed that using this environment for movement/dispersal increased the annual dispersal ability by 14 times compared with that achieved via ground (125 m), as mentioned in the literature. Therefore, river channels can serve as major pathways of long-distance dispersal for L. humile invading inland urban areas. Since applying chemical strategies around rivers is problematic, preventing L. humile from moving to rivers from initial invasion sites is crucial.


Assuntos
Formigas , Animais , Humanos , Formigas/química , Ecossistema , Japão , Rios , Agressão
3.
Toxins (Basel) ; 15(10)2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37888631

RESUMO

Ants are among the most abundant terrestrial invertebrate predators on Earth. To overwhelm their prey, they employ several remarkable behavioral, physiological, and biochemical innovations, including an effective paralytic venom. Ant venoms are thus cocktails of toxins finely tuned to disrupt the physiological systems of insect prey. They have received little attention yet hold great promise for the discovery of novel insecticidal molecules. To identify insect-neurotoxins from ant venoms, we screened the paralytic activity on blowflies of nine synthetic peptides previously characterized in the venom of Tetramorium bicarinatum. We selected peptide U11, a 34-amino acid peptide, for further insecticidal, structural, and pharmacological experiments. Insecticidal assays revealed that U11 is one of the most paralytic peptides ever reported from ant venoms against blowflies and is also capable of paralyzing honeybees. An NMR spectroscopy of U11 uncovered a unique scaffold, featuring a compact triangular ring helix structure stabilized by a single disulfide bond. Pharmacological assays using Drosophila S2 cells demonstrated that U11 is not cytotoxic, but suggest that it may modulate potassium conductance, which structural data seem to corroborate and will be confirmed in a future extended pharmacological investigation. The results described in this paper demonstrate that ant venom is a promising reservoir for the discovery of neuroactive insecticidal peptides.


Assuntos
Venenos de Formiga , Formigas , Animais , Venenos de Formiga/farmacologia , Venenos de Formiga/química , Peptídeos/farmacologia , Peptídeos/química , Formigas/química
4.
Int J Mol Sci ; 24(19)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37834262

RESUMO

Solenopsis geminata is recognized for containing the allergenic proteins Sol g 1, 2, 3, and 4 in its venom. Remarkably, Sol g 2.1 exhibits hydrophobic binding and has a high sequence identity (83.05%) with Sol i 2 from S. invicta. Notably, Sol g 2.1 acts as a mediator, causing paralysis in crickets. Given its structural resemblance and biological function, Sol g 2.1 may play a key role in transporting hydrophobic potent compounds, which induce paralysis by releasing the compounds through the insect's nervous system. To investigate this further, we constructed and characterized the recombinant Sol g 2.1 protein (rSol g 2.1), identified with LC-MS/MS. Circular dichroism spectroscopy was performed to reveal the structural features of the rSol g 2.1 protein. Furthermore, after treating crickets with S. geminata venom, immunofluorescence and immunoblotting results revealed that the Sol g 2.1 protein primarily localizes to the neuronal cell membrane of the brain and thoracic ganglia, with distribution areas related to octopaminergic neuron cell patterns. Based on protein-protein interaction predictions, we found that the Sol g 2.1 protein can interact with octopamine receptors (OctRs) in neuronal cell membranes, potentially mediating Sol g 2.1's localization within cricket central nervous systems. Here, we suggest that Sol g 2.1 may enhance paralysis in crickets by acting as carriers of active molecules and releasing them onto target cells through pH gradients. Future research should explore the binding properties of Sol g 2.1 with ligands, considering its potential as a transporter for active molecules targeting pest nervous systems, offering innovative pest control prospects.


Assuntos
Venenos de Formiga , Formigas , Críquete , Animais , Venenos de Formiga/química , Venenos de Formiga/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Formigas/química , Peçonhas , Proteínas de Ligação ao GTP/metabolismo , Proteínas Recombinantes/metabolismo , Sistema Nervoso Central/metabolismo , Paralisia
5.
Toxins (Basel) ; 15(7)2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37505709

RESUMO

Venoms produced by arthropods act as chemical weapons to paralyze prey or deter competitors. The utilization of venom is an essential feature in the biology and ecology of venomous arthropods. Solenopsis fire ants (Hymenoptera: Formicidae) are medically important venomous ants. They have acquired different patterns of venom use to maximize their competitive advantages rendered by the venom when facing different challenges. The major components of fire ant venom are piperidine alkaloids, which have strong insecticidal and antibiotic activities. The alkaloids protect fire ants from pathogens over the course of their lives and can be used to defend them from predators and competitors. They are also utilized by some of the fire ants' natural enemies, such as phorid flies to locate host ants. Collectively, these ants' diverse alkaloid compositions and functions have ecological significance for their survival, successful invasion, and rapid range expansion. The venom alkaloids with powerful biological activities may have played an important role in shaping the assembly of communities in both native and introduced ranges.


Assuntos
Alcaloides , Venenos de Formiga , Formigas , Venenos de Artrópodes , Dípteros , Animais , Venenos de Formiga/farmacologia , Venenos de Formiga/química , Formigas/química , Alcaloides/farmacologia , Alcaloides/química
6.
J Exp Biol ; 226(16)2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37497773

RESUMO

An insect's cuticle is typically covered in a layer of wax prominently featuring various hydrocarbons involved in desiccation resistance and chemical communication. In Argentine ants (Linepithema humile), cuticular hydrocarbons (CHCs) communicate colony identity, but also provide waterproofing necessary to survive dry conditions. Theory suggests different CHC compound classes have functional trade-offs, such that selection for compounds used in communication would compromise waterproofing, and vice versa. We sampled sites of invasive L. humile populations from across California to test whether CHC differences between them can explain differences in their desiccation survival. We hypothesized that CHCs whose abundance was correlated with environmental factors would determine survival during desiccation, but our regression analysis did not support this hypothesis. Interestingly, we found the abundance of most CHCs had a negative correlation with survival, regardless of compound class. We suggest that the CHC differences between L. humile nests in California are insufficient to explain their differential survival against desiccation, and that body mass is a better predictor of desiccation survival at this scale of comparison.


Assuntos
Formigas , Animais , Formigas/química , Dessecação , Hidrocarbonetos/química , Tamanho Corporal
7.
Toxins (Basel) ; 15(2)2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828419

RESUMO

The red imported fire ant (Solenopsis invicta) is a worldwide invasive and dangerous insect that is controlled mainly by chemical insecticides. Plant-derived insecticidal compounds are generally better than synthetic insecticides for environmental compatibility and the biosafety of non-targets. The toxicity of the ethanol extract of Sophora flavescens roots against S. invicta was evaluated under laboratory conditions. The ethanol extract showed toxicity against minor and medium workers of S. invicta with 7-day LC50 values of 1426.25 and 2292.60 mg/L, respectively. By bioactivity-directed chromatographic separations using the minor worker as the test insect, two active compounds, matrine and sophocarpine, were isolated from the S. flavescens total alkaloids; their chemical structure was identified by 13C NMR data. Matrine showed toxicities against minor and medium workers with 7-day LC50 values of 46.77 and 71.49 mg/L, respectively, and for sophocarpine, 50.08 and 85.87 mg/L, respectively. The two compounds could substantially reduce the foraging response, food consumption, and aggregation of S. invicta workers at a sublethal concentration of 15 mg/L. The present research suggests that S. flavescens roots have potential as a natural control agent for red imported fire ants.


Assuntos
Formigas , Inseticidas , Animais , Formigas/química , Inseticidas/toxicidade , Sophora flavescens , Dose Letal Mediana
8.
Artigo em Inglês | MEDLINE | ID: mdl-36767271

RESUMO

Imported fire ants (IFAs), Solenopsis invicta, release their venom through multiple stings that induce inflammation, allergies, shock, and even death. Although IFA venom protein sensitization and related subcutaneous immunotherapy have been studied, few studies have examined the potential toxicity or pathogenicity of alkaloids, the main substances in IFA venom. Here, IFA alkaloids were identified and analyzed by gas chromatography-mass spectrometry; we further determined an appropriate extraction method and its effectiveness for extracting high-purity alkaloids through comparative analysis and guinea pig skin sensitivity tests. The alkaloids released from the IFA abdomen included those present in the head and thorax, and the alkaloids in the abdomen accounted for the highest proportion of the total extract. The abdominal extirpation method yielded alkaloids with a purity above 97%, and the skin irritation response score and histopathological diagnosis suggest that intradermal injection of the extracted alkaloids produced symptoms effectively simulating those of IFA stings. The successful establishment of an inflammatory model in guinea pigs stung by IFAs provides a basis for further research on the mechanism of inflammatory diseases caused by IFAs.


Assuntos
Alcaloides , Anafilaxia , Venenos de Formiga , Formigas , Mordeduras e Picadas , Cobaias , Animais , Formigas/química , Venenos de Formiga/toxicidade , Alcaloides/toxicidade
9.
Int J Biol Macromol ; 220: 193-203, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35981672

RESUMO

Botanical pesticides are biological pesticides that are environment friendly. However, their instability and short persistence limit their application. In this study, pH sensitive chitosan based rotenone (Rot) nanoparticles (CS/CMCS/Rot-NPs) were prepared using chitosan and carboxymethyl chitosan to take advantage of the acidic nature of the red fire ant midgut. Chitosan based nanoparticles showed photoprotective and slow sustained release effects on Rot and significantly increased the insecticidal activity of Rot against red fire ants. The 24-96hLC50 of CS/CMCS/Rot-NPs against red fire ants was 3.28-6.84 fold that of Rot. The CS/CMCS/Rot-NPs significantly reduced the venom alkaloid content of red fire ants and their living environment and weakened their survival by increasing their survival cost in the ecological environment. Nanotechnology combined with botanical pesticides can be used as a novel, safe, effective, and ecofriendly method to control red fire ants.


Assuntos
Alcaloides , Formigas , Quitosana , Inseticidas , Agricultura , Alcaloides/química , Animais , Formigas/química , Agentes de Controle Biológico , Preparações de Ação Retardada , Inseticidas/farmacologia , Rotenona
10.
Environ Sci Technol ; 56(17): 12440-12451, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35944015

RESUMO

Ants easily accumulate cadmium (Cd) from the food web in terrestrial ecosystems. Cd contamination may cause olfactory dysfunction and consequently disorders in the social behavior of ants. To explore the molecular mechanism underlying the effect of Cd exposure on the chemosensory process of ants, we characterized the Cd-induced variations in the expression of genes involved in chemoreception and electrophysiological and behavioral sensitivity to semiochemicals by using the red imported fire ant, Solenopsis invicta, as a model system. As a result, Cd exposure increased Cd accumulation and decreased the survival rate of S. invicta. Cd exposure altered the expression profiles of odor binding protein genes of S. invicta (SiOBPs). Specifically, SiOBP15 protein expression was upregulated upon Cd exposure. Both SiOBP7 and SiOBP15 exhibited high binding affinities to limonene, nonanal, and 2,4,6-trimethylpyridine. S. invicta exposed to Cd showed less sensitive electrophysiological and behavioral response to the three chemicals but exhibited sensitive perception to undecane. Silencing of SiOBP7 and SiOBP15 abolished the behavioral response of S. invicta to nonanal and undecane, respectively, suggesting that SiOBP7 and SiOBP15 play essential roles in the chemoreception of S. invicta. In general, our results suggest that Cd contamination may interfere with olfactory signal transduction by altering the expression of SiOBPs, consequently evoking chemosensory dysfunction in fire ants.


Assuntos
Formigas , Animais , Formigas/química , Formigas/genética , Cádmio/toxicidade , Ecossistema
11.
Ecotoxicol Environ Saf ; 238: 113592, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35526452

RESUMO

Surfactants are commonly used in detergents, soaps and agrichemical products. After use, the residual surfactants can be dispersed into environmental compartments, directly or indirectly affecting aquatic and terrestrial organisms. Ants are one of the few insects that are able to make and use tools when foraging for liquid food. However, this unique behavior of ants may be greatly affected by environmental pollutants. Here, we hypothesized that surfactants have adversarial impacts on ant foraging behavior, and tested this hypothesis by investigating the effect of TWEEN 80 (a common nonionic surfactant) on the tool use behavior of black imported fire ants (Solenopsis richteri) when foraging for liquid food (sugar water). Natural pine needles and man-made sponges were provided as tools for ants. The results revealed increasing surfactant concentration induced ants to deposit more tools and caused a higher drowning rate of ants. S. richteri tended to deposit more pine needles and tools of smaller size when exposed to surfactant. Interactions between tool type and surfactant concentration showed significant effects on tool deposition and drowning rate of ants. Addition of surfactant into sugar water increased the drowning rate and reduced the foraging activity and food collection of ant workers, suggesting that surfactant in liquid food can affect the foraging efficiency of ants. However, availability of tools reduced drowning rate and increased sugar water collected compared to without tools. Our results demonstrated that ants can adjust their tool use strategies to manage the foraging risk caused by environmental surfactant, such as increasing the amount and selecting appropriate size of the tools and assembling tools of different structures. Therefore, long-term exposure to surfactants may alter foraging behavior of ants and contribute to evolve new foraging strategy.


Assuntos
Formigas , Afogamento , Comportamento de Utilização de Ferramentas , Animais , Formigas/química , Comportamento Alimentar , Açúcares , Tensoativos/toxicidade , Água/farmacologia
12.
Toxins (Basel) ; 14(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-35051015

RESUMO

Some species of primitive predatory ants, despite living in a colony, exercise their hunting collection strategy individually; their venom is painful, paralyzing, digestive, and lethal for their prey, yet the toxins responsible for these effects are poorly known. Ectatomma opaciventre is a previously unrecorded solitary hunting ant from the Brazilian Cerrado. To overcome this hindrance, the present study performed the in vitro enzymatic, biochemical, and biological activities of E. opaciventre to better understand the properties of this venom. Its venom showed several proteins with masses ranging from 1-116 kDa, highlighting the complexity of this venom. Compounds with high enzymatic activity were described, elucidating different enzyme classes present in the venom, with the presence of the first L-amino acid oxidase in Hymenoptera venoms being reported. Its crude venom contributes to a state of blood incoagulability, acting on primary hemostasis, inhibiting collagen-induced platelet aggregation, and operating on the fibrinolysis of loose red clots. Furthermore, the E. opaciventre venom preferentially induced cytotoxic effects on lung cancer cell lines and three different species of Leishmania. These data shed a comprehensive portrait of enzymatic components, biochemical and biological effects in vitro, opening perspectives for bio-pharmacological application of E. opaciventre venom molecules.


Assuntos
Venenos de Formiga/química , Venenos de Formiga/toxicidade , Formigas/química , Venenos de Crotalídeos/química , Proteínas de Insetos/química , Venenos de Escorpião/química , Animais , Brasil
13.
mBio ; 12(6): e0188521, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34933458

RESUMO

Many fungus-growing ants engage in a defensive symbiosis with antibiotic-producing ectosymbiotic bacteria in the genus Pseudonocardia, which help protect the ants' fungal mutualist from a specialized mycoparasite, Escovopsis. Here, using germfree ant rearing and experimental pathogen infection treatments, we evaluate if Acromyrmex ants derive higher immunity to the entomopathogenic fungus Metarhizium anisopliae from their Pseudonocardia symbionts. We further examine the ecological dynamics and defensive capacities of Pseudonocardia against M. anisopliae across seven different Acromyrmex species by controlling Pseudonocardia acquisition using ant-nonnative Pseudonocardia switches, in vitro challenges, and in situ mass spectrometry imaging (MSI). We show that Pseudonocardia protects the ants against M. anisopliae across different Acromyrmex species and appears to afford higher protection than metapleural gland (MG) secretions. Although Acromyrmex echinatior ants with nonnative Pseudonocardia symbionts receive protection from M. anisopliae regardless of the strain acquired compared with Pseudonocardia-free conditions, we find significant variation in the degree of protection conferred by different Pseudonocardia strains. Additionally, when ants were reared in Pseudonocardia-free conditions, some species exhibit more susceptibility to M. anisopliae than others, indicating that some ant species depend more on defensive symbionts than others. In vitro challenge experiments indicate that Pseudonocardia reduces Metarhizium conidiospore germination area. Our chemometric analysis using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) reveals that Pseudonocardia-carrying ants produce more chemical signals than Pseudonocardia-free treatments, indicating that Pseudonocardia produces bioactive metabolites on the Acromyrmex cuticle. Our results indicate that Pseudonocardia can serve as a dual-purpose defensive symbiont, conferring increased immunity for both the obligate fungal mutualist and the ants themselves. IMPORTANCE In some plants and animals, beneficial microbes mediate host immune response against pathogens, including by serving as defensive symbionts that produce antimicrobial compounds. Defensive symbionts are known in several insects, including some leaf-cutter ants where antifungal-producing Actinobacteria help protect the fungal mutualist of the ants from specialized mycoparasites. In many defensive symbioses, the extent and specificity of defensive benefits received by the host are poorly understood. Here, using "aposymbiotic" rearing, symbiont switching experiments, and imaging mass spectrometry, we explore the ecological and chemical dynamics of the model defensive symbiosis between Acromyrmex ants and their defensive symbiotic bacterium Pseudonocardia. We show that the defensive symbiont not only protects the fungal crop of Acromyrmex but also provides protection from fungal pathogens that infect the ant workers themselves. Furthermore, we reveal that the increased immunity to pathogen infection differs among strains of defensive symbionts and that the degree of reliance on a defensive symbiont for protection varies across congeneric ant species. Taken together, our results suggest that Acromyrmex-associated Pseudonocardia have evolved broad antimicrobial defenses that promote strong immunity to diverse fungal pathogens within the ancient fungus-growing ant-microbe symbiosis.


Assuntos
Formigas/microbiologia , Metarhizium/fisiologia , Pseudonocardia/fisiologia , Simbiose , Animais , Formigas/química , Formigas/imunologia , Formigas/fisiologia , Quimiometria , Espectrometria de Massas , Pseudonocardia/química
14.
Food Funct ; 12(14): 6309-6322, 2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34085683

RESUMO

This work is aimed to evaluate the nutritional composition, and the techno-functional and in vitro physiological properties of flours made using six different insect species and the sensorial feasibility of including them in bakery products. The insect flours exhibited high protein and fat contents as their main components, highlighting the presence of chitin in ant samples. The techno-functional properties showed high oil holding, swelling, and emulsifying capacities in all the analysed insect flours, whereas their bulk density, hydration properties, and foaming capacity showed average values and no gelation capacity. Moreover, these edible insect flours exhibited effective hyperglycaemia and hyperlipidaemia properties, which together with their high antioxidant capacity are associated with beneficial in vitro physiological effects. The beetle and caterpillar flours stand out in these properties, and thus were selected to make a cupcake. The sensory evaluation confirmed that the edible beetle powder can be successfully included in baked goods to provide excellent sensory properties and very high acceptance. Thus, these insect flours may be of great interest to the food industry as a healthy source of protein, exerting a positive impact on functional and sensory food properties, and with a potential role in the prevention of diseases associated with hyperglycaemia and hyperlipidaemia.


Assuntos
Insetos Comestíveis/química , Valor Nutritivo , Animais , Antioxidantes/química , Formigas/química , Quitina/análise , Besouros/química , Gorduras na Dieta/análise , Proteínas na Dieta/análise , Manipulação de Alimentos/métodos , Indústria Alimentícia/métodos , Gryllidae/química , Humanos , Lepidópteros/química , Locusta migratoria/química , Microscopia Eletrônica de Varredura/métodos , Mariposas/química , Tenebrio/química
15.
Sci Rep ; 11(1): 10712, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34040019

RESUMO

Alien ant species (Formicidae, Hymenoptera) cause serious damage worldwide. Early detection of invasion and rapid management are significant for controlling these species. However, these attempts are sometimes hindered by the need for direct detection techniques, such as capture, visual observation, or morphological identification. In this study, we demonstrated that environmental DNA (eDNA) analysis can be used as a monitoring tool for alien ants using Linepithema humile (Argentine ant), one of the most invasive ants, as a model species. We designed a new real-time PCR assay specific to L. humile and successfully detected eDNA from the surface soil. The reliability of eDNA analysis was substantiated by comparing eDNA detection results with traditional survey results. Additionally, we examined the relationship between eDNA concentration and distance from nests and trails. Our results support the effectiveness of eDNA for alien ant monitoring and suggest that this new method could improve our ability to detect invasive ant species.


Assuntos
DNA Ambiental/isolamento & purificação , Monitoramento Ambiental , Solo/química , Animais , Formigas/química , Formigas/genética , DNA Ambiental/genética , Humanos , Espécies Introduzidas
16.
Int J Mol Sci ; 22(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922345

RESUMO

Six new water extracts (E1-E6) were obtained from nest carton produced by jet black ants Lasius fuliginosus and tested for their biochemical and bioactive properties, including antioxidative and anticancer effects. The present study demonstrated significant qualitative and quantitative differences in the content of individual biochemical constituents, as well as bioactive properties between the investigated samples. All tested extracts demonstrated antioxidant properties (determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods), and the highest antioxidative potential was recorded in extracts E1 and E2 (188.96 and 313.67 µg/mL of ascorbic acid equivalent for ABTS and 176.42 and 202.66 µg/mL for DPPH reagent). Furthermore the six extracts exhibited strong inhibitory activity towards human melanoma cells of the A-375 CRL-1619 line in a dose-dependent manner. The most interesting chemopreventive activity was exhibited by extract E2, which inhibited the proliferation of A-375 cells to the greatest extent, while having a minimal effect on Vero cells. The effect on cancer cells has been confirmed using the Electric Cell-substrate Impedance Sensing (ECIS) technique. Significant impedance changes have been detected in A-375 and Vero cells following the administration of extract E2. The obtained results are really promising and constitute the basis for further research on the nest carton of jet black ant.


Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Formigas/química , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Extratos de Tecidos/farmacologia , Animais , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
17.
Molecules ; 26(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562181

RESUMO

The African weaver ant, Oecophylla longinoda, is used as a biological control agent for the management of pests. The ant has several exocrine glands in the abdomen, including Dufour's, poison, rectal, and sternal glands, which are associated with pheromone secretions for intra-specific communication. Previous studies have analyzed the gland secretions of Dufour's and poison glands. The chemistry of the rectal and sternal glands is unknown. We re-analyzed the secretions from Dufour's and poison glands plus the rectal and sternal glands to compare their chemistries and identify additional components. We used the solid-phase microextraction (SPME) technique to collect gland headspace volatiles and solvent extraction for the secretions. Coupled gas chromatography-mass spectrometry (GC-MS) analysis detected a total of 78 components, of which 62 were being reported for the first time. These additional components included 32 hydrocarbons, 12 carboxylic acids, 5 aldehydes, 3 alcohols, 2 ketones, 4 terpenes, 3 sterols, and 1 benzenoid. The chemistry of Dufour's and poison glands showed a strong overlap and was distinct from that of the rectal and sternal glands. The different gland mixtures may contribute to the different physiological and behavioral functions in this ant species.


Assuntos
Formigas/química , Glândulas Exócrinas/química , Controle Biológico de Vetores , Abdome , Álcoois/química , Álcoois/isolamento & purificação , Aldeídos/química , Aldeídos/isolamento & purificação , Animais , Formigas/metabolismo , Ácidos Carboxílicos/química , Ácidos Carboxílicos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos/química , Hidrocarbonetos/isolamento & purificação , Cetonas/química , Cetonas/isolamento & purificação , Feromônios/biossíntese , Feromônios/química , Feromônios/isolamento & purificação , Microextração em Fase Sólida , Esteróis/química , Esteróis/isolamento & purificação , Terpenos/química , Terpenos/isolamento & purificação
18.
J Agric Food Chem ; 68(44): 12252-12258, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33089981

RESUMO

Actinidine, a methylcyclopentane monoterpenoid pyridine alkaloid, has been found in many iridoid-rich plants and insect species. In a recent research on a well-known actinidine- and iridoid-producing ant species, Tapinoma melanocephalum (Fabricius) (Hymenoptera: Formicidae), no actinidine was detected in its hexane extracts by gas chromatography-mass spectrometry analysis using a common sample injection method, but a significant amount of actinidine was detected when a solid injection technique with a thermal separation probe was used. This result led us to hypothesize that heat can induce the production of actinidine in iridoid-rich organisms. To test our hypothesis, the occurrence of actinidine was investigated in four iridoid-rich organisms under different sample preparation temperatures, including two ant species, T. melanocephalum and Iridomyrmex anceps Roger (Hymenoptera: Formicidae), and two plant species, Actinidia polygama Maxim (Ericales: Actinidiaceae) and Nepeta cataria L. (Lamiales: Lamiaceae). Within a temperature range of 50, 100, 150, 200, and 250 °C, no actinidine was detected at 50 °C, but it appeared at temperatures above 100 °C for all four species. A positive relationship was observed between the heating temperature and actinidine production. The results indicate that actinidine could be generated at high temperatures. We also found that the presence of methylcyclopentane monoterpenoid iridoids (iridodials and nepetalactone) was needed for thermally induced actinidine production in all tested samples. These results suggest that the presence of actinidine in iridoid-rich plants and ants might be a consequence of using high temperatures during sample preparation.


Assuntos
Actinidia/metabolismo , Alcaloides/química , Formigas/metabolismo , Nepeta/metabolismo , Piridinas/química , Terpenos/química , Actinidia/química , Alcaloides/metabolismo , Animais , Formigas/química , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Iridoides/química , Iridoides/metabolismo , Estrutura Molecular , Nepeta/química , Piridinas/metabolismo , Terpenos/metabolismo
19.
Recent Pat Drug Deliv Formul ; 14(2): 98-107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32942982

RESUMO

Onychomycosis is a fungal infection of the nail plate or nail bed that leads to the gradual destruction of the nail. The main difficulties in the treatment of onychomycosis refer to the duration of treatments and their side effects. Thus, it becomes relevant to look for new therapeutic alternatives in the treatment of such common diseases that are efficient without causing the undesirable side effects on the patient's body. In this way, the objective of this study was to develop an anthroposophical formula for the treatment of onychomycosis, based on Phosphorus and Formica rufa, from an extensive bibliographic survey on the functions of these components, evaluating within the principles of Anthroposophy. Considering the set of knowledge and practices on the use of these components, it was possible to arrive at a proposal therapy that can be effective for the treatment of onychomycosis. After an extensive review of several existing patents, it was observed that formulations containing Phosphorus and Formica rufa together have not been described in other studies. Subsequently, our research group published a patent of the anthroposophical formula using these two components, with the number BR1020180750755, which will be efficient to help the recovery of nails, and facilitate normal growth.


Assuntos
Medicina Antroposófica , Antifúngicos/química , Formigas/química , Onicomicose/tratamento farmacológico , Fósforo/química , Animais , Composição de Medicamentos , Humanos , Unhas/microbiologia , Patentes como Assunto
20.
Sci Rep ; 10(1): 10642, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32606423

RESUMO

Chagas disease is an important disease affecting millions of patients in the New World and is caused by a protozoan transmitted by haematophagous kissing bugs. It can be treated with drugs during the early acute phase; however, effective therapy against the chronic form of Chagas disease has yet to be discovered and developed. We herein tested the activity of solenopsin alkaloids extracted from two species of fire ants against the protozoan parasite Trypanosoma cruzi, the aetiologic agent of Chagas disease. Although IC50 determinations showed that solenopsins are more toxic to the parasite than benznidazole, the drug of choice for Chagas disease treatment, the ant alkaloids presented a lower selectivity index. As a result of exposure to the alkaloids, the parasites became swollen and rounded in shape, with hypertrophied contractile vacuoles and intense cytoplasmic vacuolization, possibly resulting in osmotic stress; no accumulation of multiple kinetoplasts and/or nuclei was detected. Overexpressing phosphatidylinositol 3-kinase-an enzyme essential for osmoregulation that is a known target of solenopsins in mammalian cells-did not prevent swelling and vacuolization, nor did it counteract the toxic effects of alkaloids on the parasites. Additional experimental results suggested that solenopsins induced a type of autophagic and programmed cell death in T. cruzi. Solenopsins also reduced the intracellular proliferation of T. cruzi amastigotes in infected macrophages in a concentration-dependent manner and demonstrated activity against Trypanosoma brucei rhodesiense bloodstream forms, which is another important aetiological kinetoplastid parasite. The results suggest the potential of solenopsins as novel natural drugs against neglected parasitic diseases caused by kinetoplastids.


Assuntos
Alcaloides/toxicidade , Venenos de Artrópodes/toxicidade , Tripanossomicidas/toxicidade , Trypanosoma cruzi/efeitos dos fármacos , Animais , Formigas/química , Apoptose , Autofagia , Células CHO , Cricetinae , Cricetulus , Macaca mulatta , Macrófagos/parasitologia , Pressão Osmótica , Trypanosoma cruzi/metabolismo , Trypanosoma cruzi/patogenicidade
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