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1.
Proc Natl Acad Sci U S A ; 119(47): e2208274119, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36383602

RESUMO

Lyme spirochetes have coevolved with ticks to optimize transmission to hosts using tick salivary molecules (TSMs) to counteract host defenses. TSMs modulate various molecular events at the tick-host interface. Lymphotoxin-beta receptor (LTßR) is a vital immune receptor and plays protective roles in host immunity against microbial infections. We found that Ltbr knockout mice were more susceptible to Lyme disease spirochetes, suggesting the involvement of LTßR signaling in tick-borne Borrelia infection. Further investigation showed that a 15-kDa TSM protein from Ixodes persulcatus (I. persulcatus salivary protein; IpSAP) functioned as an immunosuppressant to facilitate the transmission and infection of Lyme disease spirochetes. IpSAP directly interacts with LTßR to block its activation, thus inhibiting the downstream signaling and consequently suppressing immunity. IpSAP immunization provided mice with significant protection against I. persulcatus-mediated Borrelia garinii infection. Notably, the immunization showed considerable cross-protection against other Borrelia infections mediated by other ixodid ticks. One of the IpSAP homologs from other ixodid ticks showed similar effects on Lyme spirochete transmission. Together, our findings suggest that LTßR signaling plays an important role in blocking the transmission and pathogenesis of tick-borne Lyme disease spirochetes, and that IpSAP and its homologs are promising candidates for broad-spectrum vaccine development.


Assuntos
Grupo Borrelia Burgdorferi , Borrelia burgdorferi , Ixodes , Doença de Lyme , Camundongos , Animais , Borrelia burgdorferi/genética , Saliva , Ixodes/fisiologia , Receptor beta de Linfotoxina
2.
Toxicol Appl Pharmacol ; 487: 116978, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795847

RESUMO

Non-small cell lung cancer (NSCLC) is a complex malignancy with a high degree of heterogeneity, representing approximately 85% of all lung cancer cases. The treatment landscape for NSCLC has been revolutionised by incorporating targeted and immunotherapies; however, novel therapeutic modalities are consistently needed to enhance the treatment outcomes. Indeed, alternative anti-cancer therapies involving natural products have drawn the attention of clinicians and scientists owing to their remarkable chemopreventive potential, often displaying minimal toxicity. D-carvone (CN) is one such natural product that has exhibited numerous promising therapeutic benefits, yet its efficacy against NSCLC remains enigmatic. In the present study, network pharmacological studies and molecular docking in conjunction with in-vitro validation were used to elucidate the underlying mechanism of action of CN comprehensively. Different databases revealed a total of 77 putative anti-NSCLC targets of CN. The identified core targets were utilised to construct a "Compound- Target- Disease" network by Cytoscape (v3.9.0). Further analysis identified 5 core/ hub targets of CN including JAK2, ERK1, ESR1, GSK3B and HSP90AA1. Molecular docking indicated a strong binding interaction of the compound with these core targets. Also, Gene Ontology and KEGG analysis validated the involvement of multiple biological processes. Additionally, CN significantly inhibited cell proliferation, clonogenicity, and wound healing potential while promoting apoptosis in a dose-dependent manner in H1299 and A549 cell lines as examined by flow cytometry, morphological assessment, and western blotting. In conclusion, this study delineates the therapeutic effects of CN on NSCLC, thus highlighting CN as a putative drug candidate for further analysis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Monoterpenos Cicloexânicos , Neoplasias Pulmonares , Simulação de Acoplamento Molecular , Farmacologia em Rede , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Monoterpenos Cicloexânicos/farmacologia , Células A549 , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Mapas de Interação de Proteínas , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química
3.
Drug Chem Toxicol ; : 1-9, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38938090

RESUMO

Cardiotoxicity is a well-established adverse effect of several drugs across multiple therapeutic indications. It is particularly prevalent following anticancer therapy. In order to evaluate the changes in cellular metabolism associated with methotrexate cardiotoxicity, we treated Wistar rats with a single high dose of methotrexate (HDMTX), and after five days, the animals were sacrificed. We then analyzed the cardiotoxicity parameters in serum like Cardiac enzymes(CK-MB, Troponin T, ALP), Inflammatory markers (TNF-α and IL-6), oxidative stress markers (NO, NOX-2), histopathology and cardiac tissue with the goal of identifying a metabolic signature of cardiotoxicity using discovery-based metabolomics. The biochemical parameters for cardiac enzymes, oxidative stress and inflammatory markers showed a significant increase in all three categories in rats treated with HDMTX. These findings were mirrored in the histopathological analysis confirming cardiotoxicity due to HDMTX. The results showed a total of 95 metabolites that were found to be significantly (p < 0.05) modulated: either up- or downregulated in the HDMTX-treated group when compared with the control group. Using integrated pathway analysis we found these metabolites were associated with many important cardiac tissue metabolic pathways, such as the malate aspartate shuttle, taurine and hypotaurine metabolism, betaine metabolism, spermidine biosynthesis, and homocysteine degradation. Among them, L-arginine, homocysteine, and betaine were significantly upregulated, suggesting their possible association with cardiac tissue injury. Overall, we provided evidence for using untargeted metabolomics to identify novel metabolites associated with HDMTX cardiac toxicity.

4.
Opt Express ; 31(2): 1475-1485, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785182

RESUMO

As one of the simplest methods to construct snapshot spectral imagers, multispectral filter array (MSFA) has been applied to commercial miniatured spectral imagers. While most of them have fixed configurations of spectral channels, lacking flexibility and replaceability. Moreover, conventional MSFA only comprises filtering channels but lacks the panchromatic channel which is essential in detecting dim and indistinct objects. Here, we propose a modular assembly method for snapshot imager which can simultaneously acquire the object's multispectral and panchromatic information based on a customized filter array. The multispectral-panchromatic filter array is batch fabricated and integrated with the imaging senor through a modular mode. Five-band spectral images and a broadband intensity image can be efficiently acquired in a single snapshot photographing. The efficacy and accuracy of the imager are experimentally verified in imaging and spectral measurements. Owing to the modular architecture, our proposed assembly method owns the advantages of compactness, simple assembling, rapid replacement, and customized designing, which overcomes the expensiveness and complexity of scientific-level snapshot spectral imaging systems.

5.
Biomacromolecules ; 23(1): 34-46, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-34793129

RESUMO

The black-legged tick (Ixodes scapularis) is the primary vector for bacteria that cause Lyme disease (Borrelia burgdorferi), where numerous glycosylated tick proteins are involved at the interface of vector-host-pathogen interactions. Reducing the expression of key tick proteins, such as selenoprotein K (SelK), through RNA interference is a promising approach to reduce pathogen transmission, but efficient delivery of nucleic acids to arthropods has proven challenging. While cationic glycopolymers have been used as nonviral gene delivery vehicles in mammalian cells, their use in arthropod or insect gene transfection has not been established. In this study, statistical acrylamide-based cationic glycopolymers with glucose or galactose pendant groups were synthesized by reversible addition-fragmentation chain transfer polymerization, and the effects of the saccharide pendant group and cationic monomer loading on polymer cytotoxicity, RNA complexation, and SelK gene knockdown in ISE6 cells were evaluated. All polymers exhibited low cytotoxicity, yet RNA/copolymer complex cell uptake and gene knockdown were highly dependent on the saccharide structure and the N:P (amino to phosphate groups) ratio.


Assuntos
Borrelia burgdorferi , Ixodes , Doença de Lyme , Animais , Proteínas de Artrópodes/metabolismo , Borrelia burgdorferi/metabolismo , Ixodes/genética , Ixodes/metabolismo , Ixodes/microbiologia , Doença de Lyme/genética , Doença de Lyme/microbiologia , Interferência de RNA
6.
Int J Mol Sci ; 23(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35628370

RESUMO

MicroRNAs (miRNAs) are a class of small non-coding RNAs involved in many biological processes, including the immune pathways that control bacterial, parasitic, and viral infections. Pathogens probably modify host miRNAs to facilitate successful infection, so they might be useful targets for vaccination strategies. There are few data on differentially expressed miRNAs in the black-legged tick Ixodes scapularis after infection with Borrelia burgdorferi, the causative agent of Lyme disease in the United States. Small RNA sequencing and qRT-PCR analysis were used to identify and validate differentially expressed I. scapularis salivary miRNAs. Small RNA-seq yielded 133,465,828 (≥18 nucleotides) and 163,852,135 (≥18 nucleotides) small RNA reads from Borrelia-infected and uninfected salivary glands for downstream analysis using the miRDeep2 algorithm. As such, 254 miRNAs were identified across all datasets, 25 of which were high confidence and 51 low confidence known miRNAs. Further, 23 miRNAs were differentially expressed in uninfected and infected salivary glands: 11 were upregulated and 12 were downregulated upon pathogen infection. Gene ontology and network analysis of target genes of differentially expressed miRNAs predicted roles in metabolic, cellular, development, cellular component biogenesis, and biological regulation processes. Several Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, including sphingolipid metabolism; valine, leucine and isoleucine degradation; lipid transport and metabolism; exosome biogenesis and secretion; and phosphate-containing compound metabolic processes, were predicted as targets of differentially expressed miRNAs. A qRT-PCR assay was utilized to validate the differential expression of miRNAs. This study provides new insights into the miRNAs expressed in I. scapularis salivary glands and paves the way for their functional manipulation to prevent or treat B. burgdorferi infection.


Assuntos
Ixodes , Doença de Lyme , MicroRNAs , Animais , Vetores de Doenças , Ixodes/genética , Doença de Lyme/genética , MicroRNAs/genética , Nucleotídeos
7.
Int J Mol Sci ; 23(4)2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35216429

RESUMO

Colorectal cancer (CRC) is the third leading cause of death in men and the fourth in women worldwide and is characterized by deranged cellular energetics. Thymoquinone, an active component from Nigella sativa, has been extensively studied against cancer, however, its role in affecting deregulated cancer metabolism is largely unknown. Further, the phosphoinositide 3-kinase (PI3K) pathway is one of the most activated pathways in cancer and its activation is central to most deregulated metabolic pathways for supporting the anabolic needs of growing cancer cells. Herein, we provide evidence that thymoquinone inhibits glycolytic metabolism (Warburg effect) in colorectal cancer cell lines. Further, we show that such an abrogation of deranged cell metabolism was due, at least in part, to the inhibition of the rate-limiting glycolytic enzyme, Hexokinase 2 (HK2), via modulating the PI3/AKT axis. While overexpression of HK2 showed that it is essential for fueling glycolytic metabolism as well as sustaining tumorigenicity, its pharmacologic and/or genetic inhibition led to a reduction in the observed effects. The results decipher HK2 mediated inhibitory effects of thymoquinone in modulating its glycolytic metabolism and antitumor effects. In conclusion, we provide evidence of metabolic perturbation by thymoquinone in CRC cells, highlighting its potential to be used/repurposed as an antimetabolite drug, though the latter needs further validation utilizing other suitable cell and/or preclinical animal models.


Assuntos
Benzoquinonas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Glicólise/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Células HCT116 , Hexoquinase/metabolismo , Humanos , Nigella sativa/efeitos dos fármacos , Nigella sativa/metabolismo , Transdução de Sinais/fisiologia
8.
Parasite Immunol ; 43(5): e12830, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33713348

RESUMO

Ticks are haematophagous arthropods with unique molecular mechanisms for digesting host blood meal while acting as vectors for various pathogens of public health significance. The tick's pharmacologically active saliva plays a fundamental role in modulating the host's immune system for several days to weeks, depending on the tick species. The vector tick has also developed sophisticated molecular mechanisms to serve as a competent vector for pathogens, including the spotted fever group (SFG) rickettsiae. Evidence is still inadequate concerning tick-rickettsiae-host interactions and saliva-assisted transmission of the pathogen to the mammalian host. Rickettsia parkeri, of the SFG rickettsia, can cause a milder version of Rocky Mountain spotted fever known as American Boutonneuse fever. The Gulf Coast tick (Amblyomma maculatum) often transmits this pathogenic rickettsia in the USA. This review discusses the knowledge gap concerning tick-rickettsiae-host interactions by highlighting the SFG rickettsia and the Am maculatum model system. Filling this knowledge gap will provide a better understanding of the tick-rickettsiae-host interactions in disease causation, which will be crucial for developing effective methods for preventing tick-borne diseases.


Assuntos
Antioxidantes/fisiologia , Infecções por Rickettsia/microbiologia , Rickettsia/fisiologia , Carrapatos/microbiologia , Carrapatos/fisiologia , Animais , Modelos Animais de Doenças , Ixodidae/microbiologia , Ixodidae/fisiologia , Microbiota , Oxirredução , Rickettsia/classificação , Infecções por Rickettsia/transmissão , Saliva/microbiologia , Selenoproteínas/genética , Selenoproteínas/metabolismo , Simbiose
9.
Am J Pathol ; 189(1): 115-123, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30315767

RESUMO

Many aspects of rickettsial infections have been characterized, including pathogenic and immune pathways and mechanisms of rickettsial survival within the vertebrate host and tick vector. However, very few studies are focused on the complex pathogen-vector-host interactions during tick feeding. Therefore, our objective was to develop a tick transmission model of the spotted fever group of rickettsial infections to study the initial events in disease development. The most appropriate strain of mouse was identified for evaluation as a transmission model, and the course of infection, bacterial levels, histopathologic changes, and antibody response during tick transmission in mice infested with Amblyomma maculatum ticks carrying the emerging pathogen, Rickettia parkeri, were studied. Results showed distinct clinical signs in C3H/HeN mice infected intravenously, leading to selection of this mouse strain for tick transmission studies. Active infection of animals was observed after tick vector transmission. The bacteria disseminated systemically and spread to several organs at 24 hours after tick attachment, with peak bacterial load at day 6 after tick attachment. Skin, lung, and liver showed the greatest pathologic changes, with inflammatory cellular infiltration and necrosis. These findings indicate the feasibility of using murine infection with R. parkeri by A. maculatum tick transmission as a model to study different aspects of the spotted fever group of rickettsial disease establishment.


Assuntos
Vetores Aracnídeos/microbiologia , Ixodidae/microbiologia , Rickettsia/patogenicidade , Rickettsiose do Grupo da Febre Maculosa , Animais , Anticorpos Antibacterianos/imunologia , Formação de Anticorpos , Vetores Aracnídeos/imunologia , Modelos Animais de Doenças , Humanos , Inflamação/imunologia , Inflamação/patologia , Ixodidae/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Necrose , Especificidade de Órgãos , Especificidade da Espécie , Rickettsiose do Grupo da Febre Maculosa/imunologia , Rickettsiose do Grupo da Febre Maculosa/patologia , Rickettsiose do Grupo da Febre Maculosa/transmissão
10.
J Exp Biol ; 222(Pt 18)2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31413101

RESUMO

In this study, we present phenotypic and genetic data characterizing the impact of imidacloprid and caging stress on honey bee Apis mellifera physiological responses and regulation of 45 genes using targeted-RNA seq. The term 'caging stress' characterizes the effects of depriving honey bees of all hive aspects and conditions. Two cohorts of 1 day old sister bees were subjected to different conditions. One cohort was caged and fed different imidacloprid-tainted sugar solutions and the second was marked and introduced back to its natal hive. Physiological bee parameters and diet behavior were monitored daily for caged bees over several weeks. Bee samples from both cohorts were sampled weekly for RNA sequencing and oxidative stress analyses. Imidacloprid induced significant protein damage and post-ingestive aversion responses in caged bees, leading to lower tainted syrup consumption and higher water intake compared with the controls. No differentially expressed genes were observed among caged bees in regards to imidacloprid treatment. However, significant upregulation in antioxidant genes was recorded in caged bees as compared with hive bees, with overwhelming downregulation in all gene categories in caged bees at week 4. We identified two sets of genes that were constantly regulated in caged bees, including Rsod with unknown function in insects that could potentially characterize caging stress in honey bees.


Assuntos
Abelhas/fisiologia , Regulação da Expressão Gênica , Estresse Fisiológico , Animais , Abelhas/efeitos dos fármacos , Abelhas/genética , Carboidratos , Ingestão de Líquidos/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Estresse Oxidativo , RNA-Seq
11.
Mol Phylogenet Evol ; 114: 153-165, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28625763

RESUMO

Hyalomma Koch, 1844 are ixodid ticks that infest mammals, birds and reptiles, to which 27 recognized species occur across the Afrotropical, Palearctic and Oriental regions. Despite their medical and veterinary importance, the evolutionary history of the group is enigmatic. To investigate various taxonomic hypotheses based on morphology, and also some of the mechanisms involved in the diversification of the genus, we sequenced and analysed data derived from two mtDNA fragments, three nuclear DNA genes and 47 morphological characters. Bayesian and Parsimony analyses based on the combined data (2242 characters for 84 taxa) provided maximum resolution and strongly supported the monophyly of Hyalomma and the subgenus Euhyalomma Filippova, 1984 (including H. punt Hoogstraal, Kaiser and Pedersen, 1969). A predicted close evolutionary association was found between morphologically similar H. dromedarii Koch, 1844, H. somalicum Tonelli Rondelli, 1935, H. impeltatum Schulze and Schlottke, 1929 and H. punt, and together they form a sister lineage to H. asiaticum Schulze and Schlottke, 1929, H. schulzei Olenev, 1931 and H. scupense Schulze, 1919. Congruent with morphological suggestions, H. anatolicum Koch, 1844, H. excavatum Koch, 1844 and H. lusitanicum Koch, 1844 form a clade and so also H. glabrum Delpy, 1949, H. marginatum Koch, 1844, H. turanicum Pomerantzev, 1946 and H. rufipes Koch, 1844. Wide scale continental sampling revealed cryptic divergences within African H. truncatum Koch, 1844 and H. rufipes and suggested that the taxonomy of these lineages is in need of a revision. The most basal lineages in Hyalomma represent taxa currently confined to Eurasia and molecular clock estimates suggest that members of the genus started to diverge approximately 36.25 million years ago (Mya). The early diversification event coincides well with the collision of the Indian and Eurasian Plates, an event that was also characterized by large scale faunal turnover in the region. Using S-Diva, we also propose that the closure of the Tethyan seaway allowed for the genus to first enter Africa approximately 17.73Mya. In concert, our data supports the notion that tectonic events and large scale global changes in the environment contributed significantly to produce the rich species diversity currently found in the genus Hyalomma.


Assuntos
Evolução Biológica , Ixodidae/classificação , Animais , Sequência de Bases , Teorema de Bayes , Mudança Climática , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/classificação , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Variação Genética , Histonas/classificação , Histonas/genética , Ixodidae/anatomia & histologia , Filogenia , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , RNA Ribossômico 28S/classificação , RNA Ribossômico 28S/genética
12.
Saudi Pharm J ; 23(2): 138-42, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25972732

RESUMO

TITLE: Comparative evaluation of metered-dose inhaler technique demonstration among community pharmacists in Al Qassim and Al Ahsa regions, Saudi Arabia. BACKGROUND: Patients rely on the information about use of proper inhaler technique when dispensed by community pharmacists however; several studies have shown that patients are unable to show correct inhalation technique. The aim of this study is to assess the ability of community pharmacists in Al Qassim region to demonstrate proper inhalation technique of metered dose inhaler and compare the baseline outcomes with a similar study at Al-Ahsa region. METHOD: We approach 96 pharmacies in Al Qassim region as mock patient (Investigator). The investigator asks the Pharmacist to guide him about proper inhalation technique of metered dose inhaler. Investigator completes a standardized and validated checklist of 8 steps of inhaler device use immediately after leaving the pharmacy. Baseline data were compared between the two study groups et al. Ahsa and Al-Qassim for variables for effectiveness of pharmacist handling of patient queries. RESULT: A total number of 96 community pharmacies were approached in five cities of the Al Qassim province in Saudi Arabia This study has found that majority (93.7%) of community pharmacists failed to demonstrate proper inhalation technique of pMDI inhaler. CONCLUSION: The pharmacists demonstrated particularly poor skills involving steps for coordination of the actuation process with the mechanics of inhalation with MDI. The errors detected in this simple assessment session, if translated to patient self-medication errors, are potentially significant.

13.
Acta Crystallogr D Biol Crystallogr ; 70(Pt 3): 789-801, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24598748

RESUMO

Glutaminyl cyclases (QCs) from mammals and Drosophila are zinc-dependent enzymes that catalyze N-terminal pyroglutamate formation of numerous proteins and peptides. These enzymes have been found to be critical for the oviposition and embryogenesis of ticks, implying that they are possible physiological targets for tick control. Here, 1.10-1.15 Šresolution structures of a metal-independent QC from the black-legged tick Ixodes scapularis (Is-QC) are reported. The structures exhibit the typical scaffold of mammalian QCs but have two extra disulfide bridges that stabilize the central ß-sheet, resulting in an increased thermal stability. Is-QC contains ~0.5 stoichiometric zinc ions, which could be removed by 1 mM EDTA. Compared with the Zn-bound form, apo-Is-QC has a nearly identical active-site structure and stability, but unexpectedly possesses significantly increased QC activities towards both synthetic and physiological substrates. Enzyme-kinetic analysis revealed that apo-Is-QC has a stronger substrate-binding affinity, suggesting that bound zinc interferes with substrate binding during catalysis. The structures of Is-QC bound to the inhibitor PBD150 revealed similar binding modes to both forms of Is-QC, with the exception of the inhibitor imidazole ring, which is consistent with the comparable inhibition activities of the inhibitor towards both forms of Is-QC. These findings have implications for the design of new QC inhibitors.


Assuntos
Aminoaciltransferases/antagonistas & inibidores , Aminoaciltransferases/química , Proteínas de Artrópodes/química , Ixodes/enzimologia , Aminoaciltransferases/metabolismo , Animais , Proteínas de Artrópodes/antagonistas & inibidores , Proteínas de Artrópodes/metabolismo , Biocatálise , Domínio Catalítico , Estabilidade Enzimática , Imidazóis/química , Imidazóis/metabolismo , Ixodes/metabolismo , Ligação Proteica/genética , Especificidade por Substrato , Temperatura , Zinco/química
14.
J Med Entomol ; 51(1): 119-29, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24605461

RESUMO

The aim of this study was to survey the bacterial diversity of Amblyomma maculatum Koch, 1844, and characterize its infection with Rickettsia parkeri. Pyrosequencing of the bacterial 16S rRNA was used to determine the total bacterial population in A. maculatum. Pyrosequencing analysis identified Rickettsia in A. maculatum midguts, salivary glands, and saliva, which indicates successful trafficking in the arthropod vector. The identity of Rickettsia spp. was determined based on sequencing the rickettsial outer membrane protein A (rompA) gene. The sequence homology search revealed the presence of R. parkeri, Rickettsia amblyommii, and Rickettsia endosymbiont ofA. maculatum in midgut tissues, whereas the only rickettsia detected in salivary glands was R. parkeri, suggesting it is unique in its ability to migrate from midgut to salivary glands, and colonize this tissue before dissemination to the host. Owing to its importance as an emerging infectious disease, the R. parkeri pathogen burden was quantified by a rompB-based quantitative polymerase chain reaction (qPCR) assay and the diagnostic effectiveness of using R. parkeri polyclonal antibodies in tick tissues was tested. Together, these data indicate that field-collected A. maculatum had a R. parkeri infection rate of 12-32%. This study provides an insight into the A. maculatum microbiome and confirms the presence of R. parkeri, which will serve as the basis for future tick and microbiome interaction studies.


Assuntos
Vetores Artrópodes/microbiologia , Ixodidae/microbiologia , Microbiota , Rickettsia/isolamento & purificação , Animais , Feminino , Interações Hospedeiro-Patógeno , Masculino , Camundongos , Coelhos
15.
Front Cell Infect Microbiol ; 14: 1427562, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086604

RESUMO

Background: MicroRNAs (miRNAs) represent a subset of small noncoding RNAs and carry tremendous potential for regulating gene expression at the post-transcriptional level. They play pivotal roles in distinct cellular mechanisms including inhibition of bacterial, parasitic, and viral infections via immune response pathways. Intriguingly, pathogens have developed strategies to manipulate the host's miRNA profile, fostering environments conducive to successful infection. Therefore, changes in an arthropod host's miRNA profile in response to pathogen invasion could be critical in understanding host-pathogen dynamics. Additionally, this area of study could provide insights into discovering new targets for disease control and prevention. The main objective of the present study is to investigate the functional role of differentially expressed miRNAs upon Ehrlichia chaffeensis, a tick-borne pathogen, infection in tick vector, Amblyomma americanum. Methods: Small RNA libraries from uninfected and E. chaffeensis-infected Am. americanum midgut and salivary gland tissues were prepared using the Illumina Truseq kit. Small RNA sequencing data was analyzed using miRDeep2 and sRNAtoolbox to identify novel and known miRNAs. The differentially expressed miRNAs were validated using a quantitative PCR assay. Furthermore, a miRNA inhibitor approach was used to determine the functional role of selected miRNA candidates. Results: The sequencing of small RNA libraries generated >147 million raw reads in all four libraries and identified a total of >250 miRNAs across the four libraries. We identified 23 and 14 differentially expressed miRNAs in salivary glands, and midgut tissues infected with E. chaffeensis, respectively. Three differentially expressed miRNAs (miR-87, miR-750, and miR-275) were further characterized to determine their roles in pathogen infection. Inhibition of target miRNAs significantly decreased the E. chaffeensis load in tick tissues, which warrants more in-depth mechanistic studies. Conclusions: The current study identified known and novel miRNAs and suggests that interfering with these miRNAs may impact the vectorial capacity of ticks to harbor Ehrlichia. This study identified several new miRNAs for future analysis of their functions in tick biology and tick-pathogen interaction studies.


Assuntos
Amblyomma , Ehrlichia chaffeensis , Interações Hospedeiro-Patógeno , MicroRNAs , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Ehrlichia chaffeensis/genética , Interações Hospedeiro-Patógeno/genética , Amblyomma/microbiologia , Amblyomma/genética , Ehrlichiose/microbiologia , Perfilação da Expressão Gênica , Glândulas Salivares/microbiologia , Regulação da Expressão Gênica
16.
J Innate Immun ; 16(1): 66-79, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38142680

RESUMO

INTRODUCTION: Hematophagous arthropods can acquire and transmit several pathogens of medical importance. In ticks, the innate immune system is crucial in the outcome between vector-pathogen interaction and overall vector competence. However, the specific immune response(s) elicited by the immune cells known as hemocytes remains largely undefined in Ehrlichia chaffeensis and its competent tick vector, Amblyomma americanum. METHODS: We utilized injection of clodronate liposome to deplete tick granulocytes combined with infection with E. chaffeensis to demonstrate their essential role in microbial infection. RESULTS: Here, we show that granulocytes, professional phagocytic cells, are integral in eliciting immune responses against commensal and pathogen infection. The chemical depletion of granulocytes led to decreased phagocytic efficiency of tissue-associated hemocytes. We demonstrate that E. chaffeensis can infect circulating hemocytes, and both cell-free plasma and hemocytes from E. chaffeensis-infected ticks can establish Ehrlichia infection in recipient ticks. Lastly, we provide evidence to show that granulocytes play a dual role in E. chaffeensis infection. Depleting granulocytic hemocytes increased Ehrlichia load in the salivary gland and midgut tissues. In contrast, granulocyte depletion led to a reduced systemic load of Ehrlichia. CONCLUSION: This study has identified multiple roles for granulocytic hemocytes in the control and systemic dissemination of E. chaffeensis infection.


Assuntos
Ehrlichia chaffeensis , Ehrlichiose , Ixodidae , Animais , Ehrlichia chaffeensis/fisiologia , Amblyomma , Hemócitos , Fagócitos
17.
bioRxiv ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38765993

RESUMO

Background: MicroRNAs (miRNAs) represent a subset of small noncoding RNAs and carry tremendous potential for regulating gene expression at the post-transcriptional level. They play pivotal roles in distinct cellular mechanisms including inhibition of bacterial, parasitic, and viral infections via immune response pathways. Intriguingly, pathogens have developed strategies to manipulate the host's miRNA profile, fostering environments conducive to successful infection. Therefore, changes in an arthropod host's miRNA profile in response to pathogen invasion could be critical in understanding host-pathogen dynamics. Additionally, this area of study could provide insights into discovering new targets for disease control and prevention. The main objective of the present study is to investigate the functional role of differentially expressed miRNAs upon Ehrlichia chaffeensis, a tick-borne pathogen, infection in tick vector, Amblyomma americanum. Methods: Small RNA libraries from uninfected and E. chaffeensis-infected Am. americanum midgut and salivary gland tissues were prepared using the Illumina Truseq kit. Small RNA sequencing data was analyzed using miRDeep2 and sRNAtoolbox to identify novel and known miRNAs. The differentially expressed miRNAs were validated using a quantitative PCR assay. Furthermore, a miRNA inhibitor approach was used to determine the functional role of selected miRNA candidates. Results: The sequencing of small RNA libraries generated >147 million raw reads in all four libraries and identified a total of >250 miRNAs across the four libraries. We identified 23 and 14 differentially expressed miRNAs in salivary glands, and midgut tissues infected with E. chaffeensis, respectively. Three differentially expressed miRNAs (miR-87, miR-750, and miR-275) were further characterized to determine their roles in pathogen infection. Inhibition of target miRNAs significantly decreased the E. chaffeensis load in tick tissues, which warrants more in-depth mechanistic studies. Conclusions: The current study identified known and novel miRNAs and suggests that interfering with these miRNAs may impact the vectorial capacity of ticks to harbor Ehrlichia. This study identified several new miRNAs for future analysis of their functions in tick biology and tick-pathogen interaction studies.

18.
Ticks Tick Borne Dis ; 15(6): 102384, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39053323

RESUMO

Alpha-Gal Syndrome (AGS) is a delayed allergic reaction triggered by IgE antibodies targeting galactose-α-1,3-galactose (α-gal), prevalent in red meat. Its global significance has increased, with over 450,000 estimated cases in the United States alone. AGS is linked to tick bites, causing sensitization and elevated α-gal specific IgE levels. However, the precise mechanisms and tick intrinsic factors contributing to AGS development post-tick bites remain unclear. This study aims to characterize the alpha-gal conjugated lipid antigens in Amblyomma americanum (Am. americanum) salivary glands and saliva. Nanospray ionization mass spectrometry (NSI-MS) analysis revealed the identification of α-gal bound lipid antigens in Am. americanum saliva. Additionally, the activation of basophils by extracted alpha-gal bound lipids and proteins provides evidence of their antigenic capabilities.

19.
Discov Oncol ; 15(1): 257, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960937

RESUMO

To address the prevalent genistein (GST) metabolism and inadequate intestinal absorption, an oral long-acting and gastric in-situ gelling gel was designed to encapsulate and localize the intestinal release of the loaded genistein-ginseng (GST-GNS) solid dispersion. Because of the high breast perfusion of GST upon oral absorption, the GST-GNS solid dispersion was developed to enhance GST's dissolution and penetration while offering a synergistic impact against breast cancer (BC). Physiochemical analysis of the GST-GNS solid dispersion, release analysis, gel characterizations, storage stability, penetration, and in vitro cytotoxicity studies were carried out. GST-GNS solid dispersion showed improved dissolution and penetration as compared to raw GST. GST-GNS solid dispersion homogenous shape particles and hydrophilic contacts were revealed by scanning electron microscopy and Fourier Transform-Infrared analysis, respectively. GST-GNS solid dispersion's diffractogram shows the amorphous character. A second modification involved creating a gastric in-situ gelling system loaded with GST-GNS solid dispersion. This system demonstrated improved GST penetration employing the solid dispersion, as well as the localizing of the GST release at the intestinal media and antitumor synergism against BC. For a better therapeutic approach for BC, the innovative oral GST long-acting gel encasing the GST-GNS solid dispersion would be recommended.

20.
Front Cell Dev Biol ; 12: 1460705, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376631

RESUMO

Ticks are important blood feeding ectoparasites that transmit pathogens to wildlife, domestic animals, and humans. Hard ticks can feed for several days to weeks, nevertheless they often go undetected. This phenomenon can be explained by a tick's ability to release analgesics, immunosuppressives, anticoagulants, and vasodilators within their saliva. Several studies have identified extracellular vesicles (EVs) as carriers of some of these effector molecules. Further, EVs, and their contents, enhance pathogen transmission, modulate immune responses, and delay wound healing. EVs are double lipid-membrane vesicles that transport intracellular cargo, including microRNAs (miRNAs) to recipient cells. miRNAs are involved in regulating gene expression post-transcriptionally. Interestingly, tick-derived miRNAs have been shown to enhance pathogen transmission and affect vital biological processes such as oviposition, blood digestion, and molting. miRNAs have been found within tick salivary EVs. This review focuses on current knowledge of miRNA loading into EVs and homologies reported in ticks. We also describe findings in tick miRNA profiles, including miRNAs packed within tick salivary EVs. Although no functional studies have been done to investigate the role of EV-derived miRNAs in tick feeding, we discuss the functional characterization of miRNAs in tick biology and pathogen transmission. Lastly, we propose the possible uses of tick miRNAs to develop management tools for tick control and to prevent pathogen transmission. The identification and functional characterization of conserved and tick-specific salivary miRNAs targeting important molecular and immunological pathways within the host could lead to the discovery of new therapeutics for the treatment of tick-borne and non-tick-borne human diseases.

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