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1.
Front Immunol ; 14: 1212167, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38022511

RESUMEN

Hepatocytes play a crucial role in host response to infection. Ehrlichia is an obligate intracellular bacterium that causes potentially life-threatening human monocytic ehrlichiosis (HME) characterized by an initial liver injury followed by sepsis and multi-organ failure. We previously showed that infection with highly virulent Ehrlichia japonica (E. japonica) induces liver damage and fatal ehrlichiosis in mice via deleterious MyD88-dependent activation of CASP11 and inhibition of autophagy in macrophage. While macrophages are major target cells for Ehrlichia, the role of hepatocytes (HCs) in ehrlichiosis remains unclear. We investigated here the role of MyD88 signaling in HCs during infection with E. japonica using primary cells from wild-type (WT) and MyD88-/- mice, along with pharmacologic inhibitors of MyD88 in a murine HC cell line. Similar to macrophages, MyD88 signaling in infected HCs led to deleterious CASP11 activation, cleavage of Gasdermin D, secretion of high mobility group box 1, IL-6 production, and inflammatory cell death, while controlling bacterial replication. Unlike macrophages, MyD88 signaling in Ehrlichia-infected HCs attenuated CASP1 activation but activated CASP3. Mechanistically, active CASP1/canonical inflammasome pathway negatively regulated the activation of CASP3 in infected MyD88-/- HCs. Further, MyD88 promoted autophagy induction in HCs, which was surprisingly associated with the activation of the mammalian target of rapamycin complex 1 (mTORC1), a known negative regulator of autophagy. Pharmacologic blocking mTORC1 activation in E. japonica-infected WT, but not infected MyD88-/- HCs, resulted in significant induction of autophagy, suggesting that MyD88 promotes autophagy during Ehrlichia infection not only in an mTORC1-indpenedent manner, but also abrogates mTORC1-mediated inhibition of autophagy in HCs. In conclusion, this study demonstrates that hepatocyte-specific regulation of autophagy and inflammasome pathway via MyD88 is distinct than MyD88 signaling in macrophages during fatal ehrlichiosis. Understanding hepatocyte-specific signaling is critical for the development of new therapeutics against liver-targeting pathogens such as Ehrlichia.


Asunto(s)
Ehrlichiosis , Inflamasomas , Animales , Humanos , Ratones , Autofagia , Caspasa 3/metabolismo , Ehrlichia , Ehrlichiosis/microbiología , Hepatocitos/metabolismo , Inflamasomas/metabolismo , Mamíferos/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo
2.
PLoS Pathog ; 19(11): e1011791, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37956169

RESUMEN

Ehrlichia is Gram negative obligate intracellular bacterium that cause human monocytotropic ehrlichiosis (HME). HME is characterized by acute liver damage and inflammation that may progress to fatal toxic shock. We previously showed that fatal ehrlichiosis is due to deleterious activation of inflammasome pathways, which causes excessive inflammation and liver injury. Mammalian cells have developed mechanisms to control oxidative stress via regulation of nuclear factor erythroid 2 related 2 (NRF2) signaling. However, the contribution of NRF2 signaling to Ehrlichia-induced inflammasome activation and liver damage remains elusive. In this study, we investigated the contribution of NRF2 signaling in hepatocytes (HCs) to the pathogenesis of Ehrlichia-induced liver injury following infection with virulent Ixodes ovatus Ehrlichia (IOE, AKA E. japonica). Employing murine model of fatal ehrlichiosis, we found that virulent IOE inhibited NRF2 signaling in liver tissue of infected mice and in HCs as evidenced by downregulation of NRF2 expression, and downstream target GPX4, as well as decreased NRF2 nuclear translocation, a key step in NRF2 activation. This was associated with activation of non-canonical inflammasomes pathway marked by activation of caspase 11, accumulation of reactive oxygen species (ROS), mitochondrial dysfunction, and endoplasmic reticulum (ER) stress. Mechanistically, treatment of IOE-infected HCs with the antioxidant 3H-1,2-Dithiole-3-Thione (D3T), that induces NRF2 activation, attenuated oxidative stress and caspase 11 activation, as well as restored cell viability. Importantly, treatment of IOE-infected mice with D3T resulted in attenuated liver pathology, decreased inflammation, enhanced bacterial clearance, prolonged survival, and resistance to fatal ehrlichiosis. Our study reveals, for the first time, that targeting anti-oxidative signaling pathway is a key approach in the treatment of severe and potential Ehrlichia-induced acute liver injury and sepsis.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Ehrlichiosis , Ratones , Humanos , Animales , Ehrlichia , Antioxidantes , Factor 2 Relacionado con NF-E2/metabolismo , Inflamasomas , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/patología , Ehrlichiosis/microbiología , Hígado/patología , Caspasas/metabolismo , Transducción de Señal , Inflamación/patología , Ratones Endogámicos C57BL , Mamíferos
3.
Cells ; 12(22)2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37998332

RESUMEN

Activating inflammatory caspases and releasing pro-inflammatory mediators are two essential functions of inflammasomes which are triggered in response to pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs). The canonical inflammasome pathway involves the activation of inflammasome and its downstream pathway via the adaptor ASC protein, which causes caspase 1 activation and, eventually, the cleavage of pro-IL-1b and pro-IL-18. The non-canonical inflammasome pathway is induced upon detecting cytosolic lipopolysaccharide (LPS) by NLRP3 inflammasome in Gram-negative bacteria. The activation of NLRP3 triggers the cleavage of murine caspase 11 (human caspase 4 or caspase 5), which results in the formation of pores (via gasdermin) to cause pyroptosis. Ehrlichia is an obligately intracellular bacterium which is responsible for causing human monocytic ehrlichiosis (HME), a potentially lethal disease similar to toxic shock syndrome and septic shock syndrome. Several studies have indicated that canonical and non-canonical inflammasome activation is a crucial pathogenic mechanism that induces dysregulated inflammation and host cellular death in the pathophysiology of HME. Mechanistically, the activation of canonical and non-canonical inflammasome pathways affected by virulent Ehrlichia infection is due to a block in autophagy. This review aims to explore the significance of non-canonical inflammasomes in ehrlichiosis, and how the pathways involving caspases (with the exception of caspase 1) contribute to the pathophysiology of severe and fatal ehrlichiosis. Improving our understanding of the non-canonical inflammatory pathway that cause cell death and inflammation in ehrlichiosis will help the advancement of innovative therapeutic, preventative, and diagnostic approaches to the treatment of ehrlichiosis.


Asunto(s)
Ehrlichiosis , Inflamasomas , Animales , Ratones , Humanos , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR , Caspasa 1 , Ehrlichiosis/metabolismo , Ehrlichiosis/patología , Caspasas/metabolismo , Inflamación , Piroptosis
4.
Antimicrob Agents Chemother ; 67(11): e0057423, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37819119

RESUMEN

Indiscriminate use of antibiotics has imposed a selective pressure for the rapid rise in bacterial resistance, creating an urgent need for novel therapeutics for managing bacterial infectious diseases while counteracting bacterial resistance. Carbapenem-resistant Klebsiella pneumoniae strains have become a major challenge in modern medicine due to their ability to cause an array of severe infections. Recently, we have shown that the 20-mer random peptide mixtures are effective therapeutics against three ESKAPEE pathogens. Here, we evaluated the toxicity, biodistribution, bioavailability, and efficacy of the ultra-short palmitoylated 5-mer phenylalanine:lysine (FK5P) random peptide mixtures against multiple clinical isolates of carbapenem-resistant K. pneumoniae and K. oxytoca. We demonstrate the FK5P rapidly and effectively killed various strains of K. pneumoniae, inhibited the formation of biofilms, and disrupted mature biofilms. FK5P displayed strong toxicity profiles both in vitro and in mice, with prolonged favorable biodistribution and a long half-life. Significantly, FK5P reduced the bacterial burden in mouse models of acute pneumonia and bacteremia and increased the survival rate in a mouse model of bacteremia. Our results demonstrate that FK5P is a safe and promising therapy against Klebsiella species as well as other ESKAPEE pathogens.


Asunto(s)
Bacteriemia , Infecciones por Klebsiella , Ratones , Animales , Klebsiella pneumoniae , Distribución Tisular , Infecciones por Klebsiella/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Carbapenémicos/farmacología , Carbapenémicos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana
5.
Int J Mol Sci ; 24(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37511399

RESUMEN

The period during which tissue and organ development occurs is particularly vulnerable to the influence of environmental exposures. However, the specific mechanisms through which biological pathways are disrupted in response to developmental insults, consequently elevating the risk of hormone-dependent diseases, such as uterine fibroids (UFs), remain poorly understood. Here, we show that developmental exposure to the endocrine-disrupting chemical (EDC), diethylstilbestrol (DES), activates the inflammatory pathways in myometrial stem cells (MMSCs), which are the origin of UFs. Significantly, the secretome of reprogrammed MMSCs enhances the expression of critical inflammation-related genes in differentiated myometrial cells through the paracrine mechanism, which amplifies pro-inflammatory and immune suppression signaling in the myometrium. The expression of reprogrammed inflammatory responsive genes (IRGs) is driven by activated mixed-lineage leukemia protein-1 (MLL1) in MMSCs. The deactivation of MLL reverses the reprogramming of IRG expression. In addition, the inhibition of histone deacetylases (HDACs) also reversed the reprogrammed IRG expression induced by EDC exposure. This work identifies the epigenetic mechanisms of MLL1/HDAC-mediated MMSC reprogramming, and EDC exposure epigenetically targets MMSCs and imparts an IRG expression pattern, which may result in a "hyper-inflammatory phenotype" and an increased hormone-dependent risk of UFs later in life.


Asunto(s)
Leiomioma , Neoplasias Uterinas , Femenino , Humanos , Miometrio/metabolismo , Leiomioma/genética , Leiomioma/metabolismo , Células Madre/metabolismo , Hormonas/metabolismo , Epigénesis Genética , Neoplasias Uterinas/genética
6.
Cells ; 12(9)2023 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-37174734

RESUMEN

Autophagy is a cellular process that involves the cell breakdown and recycling of cellular components, such as old, damaged, or abnormal proteins, for important cellular functions including development, immune function, stress, and starvation [...].


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Ehrlichia , Humanos , Autofagia , Fenómenos Fisiológicos Celulares
7.
Zoonoses (Burlingt) ; 2(1)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35876763

RESUMEN

Human monocytic ehrlichiosis, a tick transmitted infection, ranges in severity from apparently subclinical to a fatal toxic shock-like fatal disease. Models in immunocompetent mice range from an abortive infection to uniformly lethal depending on the infecting Ehrlichia species, dose of inoculum, and route of inoculation. Effective immunity is mediated by CD4+ T lymphocytes and gamma interferon. Lethal infection occurs with early overproduction of proinflammatory cytokines and overproduction of TNF alpha and IL-10 by CD8+ T lymphocytes. Furthermore, fatal ehrlichiosis is associated with signaling via TLR 9/MyD88 with upregulation of several inflammasome complexes and secretion of IL-1 beta, IL-1 alpha, and IL-18 by hepatic mononuclear cells, suggesting activation of canonical and noncanonical inflammasome pathways, a deleterious role for IL-18, and the protective role for caspase 1. Autophagy promotes ehrlichial infection, and MyD88 signaling hinders ehrlichial infection by inhibiting autophagy induction and flux. Activation of caspase 11 during infection of hepatocytes by the lethal ehrlichial species after interferon alpha receptor signaling results in the production of inflammasome-dependent IL-1 beta, extracellular secretion of HMGB1, and pyroptosis. The high level of HMGB1 in lethal ehrlichiosis suggests a role in toxic shock. Studies of primary bone marrow-derived macrophages infected by highly avirulent or mildly avirulent ehrlichiae reveal divergent M1 and M2 macrophage polarization that links with generation of pathogenic CD8 T cells, neutrophils, and excessive inflammation or with strong expansion of protective Th1 and NKT cells, resolution of inflammation and clearance of infection, respectively.

8.
Antibiotics (Basel) ; 11(3)2022 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-35326876

RESUMEN

Antibiotic resistance is one of the greatest crises in human medicine. Increased incidents of antibiotic resistance are linked to clinical overuse and overreliance on antibiotics. Among the ESKAPE pathogens, Acinetobacter baumannii, especially carbapenem-resistant isolates, has emerged as a significant threat in the context of blood, urinary tract, lung, and wound infections. Therefore, new approaches that limit the emergence of antibiotic resistant A. baumannii are urgently needed. Recently, we have shown that random peptide mixtures (RPMs) are an attractive alternative class of drugs to antibiotics with strong safety and pharmacokinetic profiles. RPMs are antimicrobial peptide mixtures produced by incorporating two amino acids at each coupling step, rendering them extremely diverse but still defined in their overall composition, chain length, and stereochemistry. The extreme diversity of RPMs may prevent bacteria from evolving resistance rapidly. Here, we demonstrated that RPMs rapidly and efficiently kill different strains of A. baumannii, inhibit biofilm formation, and disrupt mature biofilms. Importantly, RPMs attenuated bacterial burden in mouse models of acute pneumonia and soft tissue infection and significantly reduced mouse mortality during sepsis. Collectively, our results demonstrate RPMs have the potential to be used as powerful therapeutics against antibiotic-resistant A. baumannii.

9.
Front Cell Infect Microbiol ; 12: 1059825, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36590579

RESUMEN

Every year, millions of women are affected by genital tract disorders, such as bacterial vaginosis (BV), endometrial cancer, polycystic ovary syndrome (PCOS), endometriosis, and uterine fibroids (UFs). These disorders pose a significant economic burden on healthcare systems and have serious implications for health and fertility outcomes. This review explores the relationships between gut, vaginal, and uterine dysbiosis and the pathogenesis of various diseases of the female genital tract. In recent years, reproductive health clinicians and scientists have focused on the microbiome to investigate its role in the pathogenesis and prevention of such diseases. Recent studies of the gut, vaginal, and uterine microbiomes have identified patterns in bacterial composition and changes across individuals' lives associated with specific healthy and diseased states, particularly regarding the effects of the estrogen-gut microbiome axis on estrogen-driven disorders (such as endometrial cancer, endometriosis, and UFs) and disorders associated with estrogen deficiency (such as PCOS). Furthermore, this review discusses the contribution of vitamin D deficiency to gut dysbiosis and altered estrogen metabolism as well as how these changes play key roles in the pathogenesis of UFs. More research on the microbiome influences on reproductive health and fertility is vital.


Asunto(s)
Neoplasias Endometriales , Endometriosis , Microbiota , Síndrome del Ovario Poliquístico , Femenino , Humanos , Disbiosis/microbiología , Síndrome del Ovario Poliquístico/metabolismo , Vagina/microbiología , Estrógenos
10.
EBioMedicine ; 75: 103736, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34922321

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has killed millions of people worldwide. The current crisis has created an unprecedented demand for rapid test of SARS-CoV-2 infection. METHODS: Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a fast and convenient method to amplify and identify the transcripts of a targeted pathogen. However, the sensitivity and specificity of RT-LAMP were generally regarded as inferior when compared with the gold standard RT-qPCR. To address this issue, we combined bioinformatic and experimental analyses to improve the assay performance for COVID-19 diagnosis. FINDINGS: First, by experimental screening as well as high-throughput sequencing studies, we discovered new primer features that impacted LAMP sensitivity and specificity. These features were then used to build an improved bioinformatics algorithm to design LAMP primers targeting SARS-CoV-2. We further rigorously validated these new assays for their efficacy and specificity. We demonstrated that multiplexed RT-LAMP assay could directly detect as low as 1.5 copies/µL of SARS-CoV-2 particles in saliva, without the need of RNA isolation. We further tested this ultra-sensitive and specific RT-LAMP assay using saliva samples from COVID-19 patients. Clinical validation results indicated that the new RT-LAMP assay was comparable to standard RT-qPCR in overall assay sensitivity and specificity. INTERPRETATION: In summary, our new LAMP primer design algorithm along with the validated assays provide a fast and reliable method for the diagnosis of COVID-19 cases. FUNDING: National Institutes of Health.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19 , COVID-19 , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , ARN Viral/genética , SARS-CoV-2/genética , Saliva/virología , COVID-19/diagnóstico , COVID-19/genética , Humanos , Sensibilidad y Especificidad
11.
Light Sci Appl ; 10(1): 176, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34465726

RESUMEN

Efforts to mitigate the COVID-19 crisis revealed that fast, accurate, and scalable testing is crucial for curbing the current impact and that of future pandemics. We propose an optical method for directly imaging unlabeled viral particles and using deep learning for detection and classification. An ultrasensitive interferometric method was used to image four virus types with nanoscale optical path-length sensitivity. Pairing these data with fluorescence images for ground truth, we trained semantic segmentation models based on U-Net, a particular type of convolutional neural network. The trained network was applied to classify the viruses from the interferometric images only, containing simultaneously SARS-CoV-2, H1N1 (influenza-A virus), HAdV (adenovirus), and ZIKV (Zika virus). Remarkably, due to the nanoscale sensitivity in the input data, the neural network was able to identify SARS-CoV-2 vs. the other viruses with 96% accuracy. The inference time for each image is 60 ms, on a common graphic-processing unit. This approach of directly imaging unlabeled viral particles may provide an extremely fast test, of less than a minute per patient. As the imaging instrument operates on regular glass slides, we envision this method as potentially testing on patient breath condensates. The necessary high throughput can be achieved by translating concepts from digital pathology, where a microscope can scan hundreds of slides automatically.

12.
Stem Cell Res Ther ; 12(1): 388, 2021 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-34233746

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in reproductive-age women. Excessive inflammation and elevated androgen production from ovarian theca cells are key features of PCOS. Human bone marrow mesenchymal stem cells (BM-hMSC) and their secreted factors (secretome) exhibit robust anti-inflammatory capabilities in various biological systems. We evaluated the therapeutic efficacy of BM-hMSC and its secretome in both in vitro and in vivo PCOS models. METHODS: For in vitro experiment, we treated conditioned media from BM-hMSC to androgen-producing H293R cells and analyzed androgen-producing gene expression. For in vivo experiment, BM-hMSC were implanted into letrozole (LTZ)-induced PCOS mouse model. BM-hMSC effect in androgen-producing cells or PCOS model mice was assessed by monitoring cell proliferation (immunohistochemistry), steroidogenic gene expression (quantitative real-time polymerase chain reaction [qRT-PCR] and Western blot, animal tissue assay (H&E staining), and fertility by pup delivery. RESULTS: BM-hMSC significantly downregulate steroidogenic gene expression, curb inflammation, and restore fertility in treated PCOS animals. The anti-inflammatory cytokine interleukin-10 (IL-10) played a key role in mediating the effects of BM-hMSC in our PCOS models. We demonstrated that BM-hMSC treatment was improved in metabolic and reproductive markers in our PCOS model and able to restore fertility. CONCLUSION: Our study demonstrates for the first time the efficacy of intra-ovarian injection of BM-hMSC or its secretome to treat PCOS-related phenotypes, including both metabolic and reproductive dysfunction. This approach may represent a novel therapeutic option for women with PCOS. Our results suggest that BM-hMSC can reverse PCOS-induced inflammation through IL-10 secretion. BM-hMSC might be a novel and robust therapeutic approach for PCOS treatment.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Síndrome del Ovario Poliquístico , Animales , Femenino , Fertilidad , Humanos , Interleucina-10/genética , Ratones , Síndrome del Ovario Poliquístico/terapia
13.
medRxiv ; 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33948614

RESUMEN

The coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has killed millions of people worldwide. The current crisis has created an unprecedented demand for rapid test of SARS-CoV-2 infection. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a fast and convenient method to amplify and identify the transcripts of a targeted pathogen. However, the sensitivity and specificity of RT-LAMP were generally regarded as inferior when compared with the gold standard RT-qPCR. To address this issue, we combined bioinformatic and experimental analyses to improve the assay performance for COVID-19 diagnosis. First, we developed an improved algorithm to design LAMP primers targeting the nucleocapsid (N), membrane (M), and spike (S) genes of SARS-CoV-2. Next, we rigorously validated these new assays for their efficacy and specificity. Further, we demonstrated that multiplexed RT-LAMP assays could directly detect as low as a few copies of SARS-CoV-2 RNA in saliva, without the need of RNA isolation. Importantly, further testing using saliva samples from COVID-19 patients indicated that the new RT-LAMP assays were in total agreement in sensitivity and specificity with standard RT-qPCR. In summary, our new LAMP primer design algorithm along with the validated assays provide a fast and reliable method for the diagnosis of COVID-19 cases.

14.
Hepatol Commun ; 5(1): 33-51, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33437899

RESUMEN

Inflammasomes are an important innate immune host defense against intracellular microbial infection. Activation of inflammasomes by microbial or host ligands results in cleavage of caspase-1 (canonical pathway) or caspase-11 (noncanonical pathway), release of interleukin (IL)-1ß, IL-18, high mobility group box 1 (HMGB1), and inflammatory cell death known as pyroptosis. Ehrlichia are obligate, intracellular, gram-negative bacteria that lack lipopolysaccharide but cause potentially life-threatening monocytic ehrlichiosis in humans and mice that is characterized by liver injury followed by sepsis and multiorgan failure. Employing murine models of mild and fatal ehrlichiosis caused by infection with mildly and highly virulent Ehrlichia muris (EM) and Ixodes ovatus Ehrlichia (IOE), respectively, we have previously shown that IOE infection triggers type I interferon (IFN-I) response and deleterious caspase-11 activation in liver tissues, which promotes liver injury and sepsis. In this study, we examined the contribution of IFN-I signaling in hepatocytes (HCs) to Ehrlichia-induced liver injury. Compared to EM infection, we found that IOE enter and replicate in vitro cultured primary murine HCs and induce secretion of IFNß and several chemokines, including regulated upon activation, normal T-cell expressed, and secreted (RANTES), monocyte chemoattractant protein 1 (MCP1), monokine induced by gamma (MIG)/chemokine (C-X-C motif) ligand 9 (CXCL9), macrophage inflammatory protein 1 alpha (MIP1α), keratinocyte-derived chemokine (KC), and granulocyte-macrophage colony-stimulating factor (GM-CSF). Notably, in vitro stimulation of uninfected and Ehrlichia-infected HCs with recombinant IFNß triggered activation of caspase-1/11, cytosolic translocation of HMGB1, and enhanced autophagy and intracellular bacterial replication. Secretion of HMGB1 by IOE-infected HCs was dependent on caspase-11. Primary HCs from IOE- but not EM-infected mice also expressed active caspase-1/11. Conclusion: HC-specific IFN-I signaling may exacerbate liver pathology during infection with obligate intracellular Ehrlichia by promoting bacterial replication and detrimental caspase-11-mediated inflammasome activation.


Asunto(s)
Ehrlichia/inmunología , Ehrlichiosis/inmunología , Hepatocitos/metabolismo , Inflamasomas/inmunología , Interferón Tipo I/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Caspasa 1/genética , Caspasa 1/inmunología , Ehrlichiosis/genética , Femenino , Proteína HMGB1/genética , Proteína HMGB1/inmunología , Interferón Tipo I/genética , Interferón gamma/inmunología , Interleucina-18/inmunología , Interleucina-1beta/inmunología , Ixodes/microbiología , Ratones , Ratones Endogámicos C57BL , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/metabolismo
16.
J Cell Immunol ; 2(3): 108-115, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32719831

RESUMEN

Human monocytic ehrlichiosis (HME) is an emerging life-threatening tick-borne disease caused by the obligate intracellular bacterium Ehrlichia chaffeensis. HME is often presented as a nonspecific flu-like illness characterized by presence of fever, headache, malaise, and myalgia. However, in some cases the disease can evolve to a severe form, which is commonly marked by acute liver injury followed by multi-organ failure and toxic shock-like syndrome [1-3]. Macrophages and monocytes are the major target cells for Ehrlichia, although this bacterium can infect other cell types such as hepatocytes and endothelial cells [4]. In this article, we discuss how macrophages polarization to M1 or M2 phenotypes dictate the severity of ehrlichiosis and the outcome of infection. We will also discuss the potential mechanisms that regulate such polarization.

17.
Reprod Sci ; 27(3): 823-832, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32046450

RESUMEN

Uterine fibroids (UFs) or leiomyoma are frequently associated with somatic mutations in the mediator complex subunit 12 (MED12) gene; however, the function of these mutations in human UF biology is yet to be determined. Herein, we determined the functional role of the most common MED12 somatic mutation in the modulation of oncogenic Wnt4/ß-catenin and mammalian target of rapamycin (mTOR) signaling pathways. Using an immortalized human uterine myometrial smooth muscle cell line (UtSM), we constitutively overexpressed either MED12-Wild Type or the most common MED12 somatic mutation (c.131G>A), and the effects of this MED12 mutation were compared between these cell lines. This immortalized cell line was used as a model because it expresses wild type MED12 protein and do not possess MED12 somatic mutations. By comparing the effect between MED12-WT and MED12-mutant (mut) stable cell populations, we observed increased levels of protein expression of Wnt4 and ß-catenin in MED12-mut cells as compared with MED12-WT cells. MED12-mut cells also expressed increased levels of mTOR protein and oncogenic cyclin D1 which are hallmarks of cell growth and tumorigenicity. This somatic mutation in MED12 showed an effect on cell-cycle progression by induction of S-phase cells. MED12-mut cells also showed inhibition of autophagy as compared with MED12-WT cells. Together, these findings indicate that the MED12 somatic mutation has the potentials for myometrial cell transformation by dysregulating oncogenic Wnt4/ß-catenin and its downstream mTOR signaling which might be associated with autophagy abrogation, cell proliferation, and tumorigenicity.


Asunto(s)
Autofagia , Leiomioma/genética , Leiomioma/metabolismo , Complejo Mediador/genética , Complejo Mediador/metabolismo , Miometrio/metabolismo , Proteína Wnt4/metabolismo , beta Catenina/metabolismo , Ciclo Celular , Ciclina D1/metabolismo , Femenino , Humanos , Mutación , Serina-Treonina Quinasas TOR/metabolismo , Vía de Señalización Wnt
18.
Nat Microbiol ; 5(1): 67-75, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31740764

RESUMEN

Gram-negative bacterial infections are a significant public health concern, and the lack of new drug classes for these pathogens is linked to the inability of most drug leads to accumulate inside Gram-negative bacteria1-7. Here, we report the development of a web application-eNTRyway-that predicts compound accumulation (in Escherichia coli) from its structure. In conjunction with structure-activity relationships and X-ray data, eNTRyway was utilized to re-design Debio-1452-a Gram-positive-only antibiotic8-into versions that accumulate in E. coli and possess antibacterial activity against high-priority Gram-negative pathogens. The lead compound Debio-1452-NH3 operates as an antibiotic via the same mechanism as Debio-1452, namely potent inhibition of the enoyl-acyl carrier protein reductase FabI, as validated by in vitro enzyme assays and the generation of bacterial isolates with spontaneous target mutations. Debio-1452-NH3 is well tolerated in vivo, reduces bacterial burden in mice and rescues mice from lethal infections with clinical isolates of Acinetobacter baumannii, Klebsiella pneumoniae and E. coli. This work provides tools for the facile discovery and development of high-accumulating compounds in E. coli, and a general blueprint for the conversion of Gram-positive-only compounds into broad-spectrum antibiotics.


Asunto(s)
Antibacterianos/farmacología , Descubrimiento de Drogas/métodos , Enoil-ACP Reductasa (NADH)/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Animales , Antibacterianos/química , Antibacterianos/farmacocinética , Benzofuranos/química , Benzofuranos/farmacocinética , Benzofuranos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Enoil-ACP Reductasa (NADH)/genética , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacocinética , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Bacterias Gramnegativas/metabolismo , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Humanos , Ratones , Pruebas de Sensibilidad Microbiana , Pironas/química , Pironas/farmacocinética , Pironas/farmacología , Programas Informáticos , Relación Estructura-Actividad
19.
Int J Endocrinol ; 2019: 3519093, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31885556

RESUMEN

BACKGROUND: Despite the high prevalence of type 2 diabetes mellitus in Gulf countries, standards of diabetes care at the primary care level have not been widely studied. AIM: To compare the results of diabetes clinical indicators from the American Diabetes Association (ADA) 2017 guidelines to the reference benchmarks in the Behavioral Risk Factor Surveillance System. MATERIALS AND METHODS: A cross-sectional analysis of electronic medical records in 643 randomly selected adult patients with type 2 diabetes was undertaken. A checklist enabled the collection of sociodemographic, clinical, biochemical, and quality measurement data. Data were analyzed using Stata 9.0. The chi-squared test was used to compare two or more proportions. RESULTS: There were 643 patients (male = 60.3%; female = 39.7%), and the majority (71.7%) aged between 40 and 64 years. Common comorbidities were dyslipidemia (72.3%), hypertension (70%), obesity (50.1%), and preobesity (overweight) (37.9%). Over 15% were smokers. The most commonly prescribed diabetes medications were metformin (89.9%), dipeptidyl peptidase-4 inhibitors (61.1%), and sulfonylureas (49.3%). Only 35.5% (p < 0.0001) of patients met the reference glycated hemoglobin (HbA1c) cutoff level of 7.0%. The reference level for blood pressure control was met by 70.2% (p < 0.0001) and for low-density lipoprotein cholesterol, 73.8% (p < 0.0001). Albuminuria was present in 39.2%, and very low vitamin D level (<20 ng/ml) in 39.1%. Most patients had annual foot (89.6%, p < 0.0001) and eye (72.3%, p < 0.0001) examinations. Only 39.9% had referrals for dietary counseling, and there were lower rates of referrals and uptake for pneumococcal, influenza, and hepatitis B vaccines. Most (76.2%) did not have screening for depression. CONCLUSION: The majority of the results met the ADA standards, while glycemic control, dietary counseling, and screening for depression were poor in comparison to the standards. Continuing education for clinicians, patient education for self-management, and targeted weight management are recommended.

20.
Immunity ; 51(6): 1088-1101.e5, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31732168

RESUMEN

The B cell response to Ehrlichia muris is dominated by plasmablasts (PBs), with few-if any-germinal centers (GCs), yet it generates protective immunoglobulin M (IgM) memory B cells (MBCs) that express the transcription factor T-bet and harbor V-region mutations. Because Ehrlichia prominently infects the liver, we investigated the nature of liver B cell response and that of the spleen. B cells within infected livers proliferated and underwent somatic hypermutation (SHM). Vh-region sequencing revealed trafficking of clones between the spleen and liver and often subsequent local clonal expansion and intraparenchymal localization of T-bet+ MBCs. T-bet+ MBCs expressed MBC subset markers CD80 and PD-L2. Many T-bet+ MBCs lacked CD11b or CD11c expression but had marginal zone (MZ) B cell phenotypes and colonized the splenic MZ, revealing T-bet+ MBC plasticity. Hence, liver and spleen are generative sites of B cell responses, and they include V-region mutation and result in liver MBC localization.


Asunto(s)
Linfocitos B/inmunología , Ehrlichia/inmunología , Ehrlichiosis/inmunología , Inmunoglobulina M/inmunología , Hígado/inmunología , Bazo/inmunología , Animales , Antígeno B7-1/biosíntesis , Región Variable de Inmunoglobulina/genética , Memoria Inmunológica/inmunología , Hígado/citología , Ratones , Ratones Endogámicos C57BL , Proteína 2 Ligando de Muerte Celular Programada 1/biosíntesis , Hipermutación Somática de Inmunoglobulina/genética , Bazo/citología , Proteínas de Dominio T Box/metabolismo
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