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1.
Biochem Pharmacol ; : 116160, 2024 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-38522554

RESUMEN

Globally, despite extensive research and pharmacological advancement, cancer remains one of the most common causes of mortality. Understanding the signaling pathways involved in cancer progression is essential for the discovery of new drug targets. The adenylyl cyclase (AC) superfamily comprises glycoproteins that regulate intracellular signaling and convert ATP into cyclic AMP, an important second messenger. The present review highlights the involvement of ACs in cancer progression and suppression, broken down for each specific mammalian AC isoform. The precise mechanisms by which ACs contribute to cancer cell proliferation and invasion are not well understood and are variable among cancer types; however, AC overactivation, along with that of downstream regulators, presents a potential target for novel anticancer therapies. The expression patterns of ACs in numerous cancers are discussed. In addition, we highlight inhibitors of AC-related signaling that are currently under investigation, with a focus on possible anti-cancer strategies. Recent discoveries with small molecules regarding more direct modulation AC activity are also discussed in detail. A more comprehensive understanding of different components in AC-related signaling could potentially lead to the development of novel therapeutic strategies for personalized oncology and might enhance the efficacy of chemoimmunotherapy in the treatment of various cancers.

2.
J Pathol ; 262(1): 105-120, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37850574

RESUMEN

HOXB13 is a key lineage homeobox transcription factor that plays a critical role in the differentiation of the prostate gland. Several studies have suggested that HOXB13 alterations may be involved in prostate cancer development and progression. Despite its potential biological relevance, little is known about the expression of HOXB13 across the disease spectrum of prostate cancer. To this end, we validated a HOXB13 antibody using genetic controls and investigated HOXB13 protein expression in murine and human developing prostates, localized prostate cancers, and metastatic castration-resistant prostate cancers. We observed that HOXB13 expression increases during later stages of murine prostate development. All localized prostate cancers showed HOXB13 protein expression. Interestingly, lower HOXB13 expression levels were observed in higher-grade tumors, although no significant association between HOXB13 expression and recurrence or disease-specific survival was found. In advanced metastatic prostate cancers, HOXB13 expression was retained in the majority of tumors. While we observed lower levels of HOXB13 protein and mRNA levels in tumors with evidence of lineage plasticity, 84% of androgen receptor-negative castration-resistant prostate cancers and neuroendocrine prostate cancers (NEPCs) retained detectable levels of HOXB13. Notably, the reduced expression observed in NEPCs was associated with a gain of HOXB13 gene body CpG methylation. In comparison to the commonly used prostate lineage marker NKX3.1, HOXB13 showed greater sensitivity in detecting advanced metastatic prostate cancers. Additionally, in a cohort of 837 patients, 383 with prostatic and 454 with non-prostatic tumors, we found that HOXB13 immunohistochemistry had a 97% sensitivity and 99% specificity for prostatic origin. Taken together, our studies provide valuable insight into the expression pattern of HOXB13 during prostate development and cancer progression. Furthermore, our findings support the utility of HOXB13 as a diagnostic biomarker for prostate cancer, particularly to confirm the prostatic origin of advanced metastatic castration-resistant tumors. © 2023 The Pathological Society of Great Britain and Ireland.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Animales , Humanos , Masculino , Ratones , Genes Homeobox , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Próstata/patología , Neoplasias de la Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Reino Unido
3.
Cancer Res Commun ; 3(9): 1756-1769, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37674528

RESUMEN

Mechanisms for Helicobacter pylori (Hp)-driven stomach cancer are not fully understood. In a transgenic mouse model of gastric preneoplasia, concomitant Hp infection and induction of constitutively active KRAS (Hp+KRAS+) alters metaplasia phenotypes and elicits greater inflammation than either perturbation alone. Gastric single-cell RNA sequencing showed that Hp+KRAS+ mice had a large population of metaplastic pit cells that expressed the intestinal mucin Muc4 and the growth factor amphiregulin. Flow cytometry and IHC-based immune profiling revealed that metaplastic pit cells were associated with macrophage and T-cell inflammation. Accordingly, expansion of metaplastic pit cells was prevented by gastric immunosuppression and reversed by antibiotic eradication of Hp. Finally, MUC4 expression was significantly associated with proliferation in human gastric cancer samples. These studies identify an Hp-associated metaplastic pit cell lineage, also found in human gastric cancer tissues, whose expansion is driven by Hp-dependent inflammation. Significance: Using a mouse model, we have delineated metaplastic pit cells as a precancerous cell type whose expansion requires Hp-driven inflammation. In humans, metaplastic pit cells show enhanced proliferation as well as enrichment in precancer and early cancer tissues, highlighting an early step in the gastric metaplasia to cancer cascade.


Asunto(s)
Helicobacter pylori , Neoplasias Gástricas , Humanos , Animales , Ratones , Proteínas Proto-Oncogénicas p21(ras) , Modelos Animales de Enfermedad , Inflamación
4.
Nat Microbiol ; 8(5): 875-888, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37037942

RESUMEN

Previous urinary tract infections (UTIs) can predispose one to future infections; however, the underlying mechanisms affecting recurrence are poorly understood. We previously found that UTIs in mice cause differential bladder epithelial (urothelial) remodelling, depending on disease outcome, that impacts susceptibility to recurrent UTI. Here we compared urothelial stem cell (USC) lines isolated from mice with a history of either resolved or chronic uropathogenic Escherichia coli (UPEC) infection, elucidating evidence of molecular imprinting that involved epigenetic changes, including differences in chromatin accessibility, DNA methylation and histone modification. Epigenetic marks in USCs from chronically infected mice enhanced caspase-1-mediated cell death upon UPEC infection, promoting bacterial clearance. Increased Ptgs2os2 expression also occurred, potentially contributing to sustained cyclooxygenase-2 expression, bladder inflammation and mucosal wounding-responses associated with severe recurrent cystitis. Thus, UPEC infection acts as an epi-mutagen reprogramming the urothelial epigenome, leading to urothelial-intrinsic remodelling and training of the innate response to subsequent infection.


Asunto(s)
Infecciones por Escherichia coli , Infecciones Urinarias , Escherichia coli Uropatógena , Ratones , Animales , Escherichia coli Uropatógena/genética , Inmunidad Entrenada , Infecciones Urinarias/microbiología , Vejiga Urinaria/microbiología , Infecciones por Escherichia coli/microbiología
5.
Front Cell Infect Microbiol ; 12: 909799, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35782131

RESUMEN

The anaerobic actinobacterium Gardnerella was first isolated from the bladder by suprapubic aspiration more than 50 years ago. Since then, Gardnerella has been increasingly recognized as a common and often abundant member of the female urinary microbiome (urobiome). Some studies even suggest that the presence of Gardnerella is associated with urological disorders in women. We recently reported that inoculation of Gardnerella into the bladders of mice results in urothelial exfoliation. Here, we performed whole bladder RNA-seq in our mouse model to identify additional host pathways involved in the response to Gardnerella bladder exposure. The transcriptional response to Gardnerella reflected the urothelial turnover that is a consequence of exfoliation while also illustrating the activation of pathways involved in inflammation and immunity. Additional timed exposure experiments in mice provided further evidence of a potentially clinically relevant consequence of bladder exposure to Gardnerella-increased susceptibility to subsequent UTI caused by uropathogenic Escherichia coli. Together, these data provide a broader picture of the bladder's response to Gardnerella and lay the groundwork for future studies examining the impact of Gardnerella on bladder health.


Asunto(s)
Infecciones por Escherichia coli , Infecciones Urinarias , Escherichia coli Uropatógena , Animales , Infecciones por Escherichia coli/microbiología , Femenino , Gardnerella , Expresión Génica , Humanos , Ratones , Vejiga Urinaria/microbiología , Infecciones Urinarias/microbiología , Escherichia coli Uropatógena/genética
6.
Front Cell Infect Microbiol ; 11: 788229, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34938672

RESUMEN

Recurrent urinary tract infections (rUTI) are a costly clinical problem affecting millions of women worldwide each year. The majority of rUTI cases are caused by uropathogenic Escherichia coli (UPEC). Data from humans and mouse models indicate that some instances of rUTI are caused by UPEC emerging from latent reservoirs in the bladder. Women with vaginal dysbiosis, typically characterized by high levels of Gardnerella and other anaerobes, are at increased risk of UTI. Multiple studies have detected Gardnerella in urine collected by transurethral catheterization (to limit vaginal contamination), suggesting that some women experience routine urinary tract exposures. We recently reported that inoculation of Gardnerella into the bladder triggers rUTI from UPEC bladder reservoirs in a mouse model. Here we performed whole bladder RNA-seq to identify host pathways involved in Gardnerella-induced rUTI. We identified a variety host pathways differentially expressed in whole bladders following Gardnerella exposure, such as pathways involved in inflammation/immunity and epithelial turnover. At the gene level, we identified upregulation of Immediate Early (IE) genes, which are induced in various cell types shortly following stimuli like infection and inflammation. One such upregulated IE gene was the orphan nuclear receptor Nur77 (aka Nr4a1). Pilot experiments in Nur77-/- mice suggest that Nur77 is necessary for Gardnerella exposure to trigger rUTI from UPEC reservoirs. These findings demonstrate that bladder gene expression can be impacted by short-lived exposures to urogenital bacteria and warrant future examination of responses in distinct cell types, such as with single cell transcriptomic technologies. The biological validation studies in Nur77-/- mice lay the groundwork for future studies investigating Nur77 and the Immediate Early response in rUTI.


Asunto(s)
Infecciones por Escherichia coli , Infecciones Urinarias , Escherichia coli Uropatógena , Animales , Femenino , Gardnerella , Ratones , Vejiga Urinaria , Escherichia coli Uropatógena/genética
7.
Life Sci Alliance ; 4(2)2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33310760

RESUMEN

More than 80% of gastric cancer is attributable to stomach infection with Helicobacter pylori (Hp). Gastric preneoplastic progression involves sequential tissue changes, including loss of parietal cells, metaplasia and dysplasia. In transgenic mice, active KRAS expression recapitulates these tissue changes in the absence of Hp infection. This model provides an experimental system to investigate additional roles of Hp in preneoplastic progression, beyond its known role in initiating inflammation. Tissue histology, gene expression, the immune cell repertoire, and metaplasia and dysplasia marker expression were assessed in KRAS+ mice +/-Hp infection. Hp+/KRAS+ mice had severe T-cell infiltration and altered macrophage polarization; a different trajectory of metaplasia; more dysplastic glands; and greater proliferation of metaplastic and dysplastic glands. Eradication of Hp with antibiotics, even after onset of metaplasia, prevented or reversed these tissue phenotypes. These results suggest that gastric preneoplastic progression differs between Hp+ and Hp- cases, and that sustained Hp infection can promote the later stages of gastric preneoplastic progression.


Asunto(s)
Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/microbiología , Helicobacter pylori/fisiología , Gastropatías/etiología , Gastropatías/patología , Animales , Ratones , Gastropatías/metabolismo
8.
J Vis Exp ; (166)2020 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-33346201

RESUMEN

Recurrent urinary tract infections (rUTI) caused by uropathogenic Escherichia coli (UPEC) are common and costly. Previous articles describing models of UTI in male and female mice have illustrated the procedures for bacterial inoculation and enumeration in urine and tissues. During an initial bladder infection in C57BL/6 mice, UPEC establish latent reservoirs inside bladder epithelial cells that persist following clearance of UPEC bacteriuria. This model builds on these studies to examine rUTI caused by the emergence of UPEC from within latent bladder reservoirs. The urogenital bacterium Gardnerella vaginalis is used as the trigger of rUTI in this model because it is frequently present in the urogenital tracts of women, especially in the context of vaginal dysbiosis that has been associated with UTI. In addition, a method for in situ bladder fixation followed by scanning electron microscopy (SEM) analysis of bladder tissue is also described, with potential application to other studies involving the bladder.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Gardnerella vaginalis/fisiología , Vejiga Urinaria/microbiología , Vejiga Urinaria/patología , Infecciones Urinarias/microbiología , Animales , Modelos Animales de Enfermedad , Reservorios de Enfermedades/microbiología , Infecciones por Escherichia coli/patología , Infecciones por Escherichia coli/orina , Femenino , Ratones Endogámicos C57BL , Recurrencia , Espectrofotometría , Vejiga Urinaria/ultraestructura , Infecciones Urinarias/patología , Infecciones Urinarias/orina , Orina/citología , Escherichia coli Uropatógena/fisiología
9.
PLoS Biol ; 18(8): e3000788, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32841232

RESUMEN

Women with bacterial vaginosis (BV), an imbalance of the vaginal microbiome, are more likely to be colonized by potential pathogens such as Fusobacterium nucleatum, a bacterium linked with intrauterine infection and preterm birth. However, the conditions and mechanisms supporting pathogen colonization during vaginal dysbiosis remain obscure. We demonstrate that sialidase activity, a diagnostic feature of BV, promoted F. nucleatum foraging and growth on mammalian sialoglycans, a nutrient resource that was otherwise inaccessible because of the lack of endogenous F. nucleatum sialidase. In mice with sialidase-producing vaginal microbiotas, mutant F. nucleatum unable to consume sialic acids was impaired in vaginal colonization. These experiments in mice also led to the discovery that F. nucleatum may also "give back" to the community by reinforcing sialidase activity, a biochemical feature of human dysbiosis. Using human vaginal bacterial communities, we show that F. nucleatum supported robust outgrowth of Gardnerella vaginalis, a major sialidase producer and one of the most abundant organisms in BV. These results illustrate that mutually beneficial relationships between vaginal bacteria support pathogen colonization and may help maintain features of dysbiosis. These findings challenge the simplistic dogma that the mere absence of "healthy" lactobacilli is the sole mechanism that creates a permissive environment for pathogens during vaginal dysbiosis. Given the ubiquity of F. nucleatum in the human mouth, these studies also suggest a possible mechanism underlying links between vaginal dysbiosis and oral sex.


Asunto(s)
Proteínas Bacterianas/genética , Disbiosis/microbiología , Fusobacterium/metabolismo , Gardnerella vaginalis/metabolismo , Neuraminidasa/genética , Polisacáridos/metabolismo , Vaginosis Bacteriana/microbiología , Animales , Proteínas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana , Disbiosis/patología , Femenino , Fusobacterium/genética , Fusobacterium/aislamiento & purificación , Fusobacterium/patogenicidad , Gardnerella vaginalis/genética , Gardnerella vaginalis/aislamiento & purificación , Gardnerella vaginalis/patogenicidad , Expresión Génica , Humanos , Ratones , Ratones Endogámicos C57BL , Microbiota/genética , Neuraminidasa/metabolismo , ARN Ribosómico 16S/genética , Ácidos Siálicos/metabolismo , Simbiosis/genética , Vagina/microbiología , Vaginosis Bacteriana/patología
10.
Elife ; 82019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31429405

RESUMEN

A mucosal infectious disease episode can render the host either more or less susceptible to recurrent infection, but the specific mechanisms that tip the balance remain unclear. We investigated this question in a mouse model of recurrent urinary tract infection and found that a prior bladder infection resulted in an earlier onset of tumor necrosis factor-alpha (TNFɑ)-mediated bladder inflammation upon subsequent bacterial challenge, relative to age-matched naive mice. However, the duration of TNFɑ signaling activation differed according to whether the first infection was chronic (Sensitized) or self-limiting (Resolved). TNFɑ depletion studies revealed that transient early-phase TNFɑ signaling in Resolved mice promoted clearance of bladder-colonizing bacteria via rapid recruitment of neutrophils and subsequent exfoliation of infected bladder cells. In contrast, sustained TNFɑ signaling in Sensitized mice prolonged damaging inflammation, worsening infection. This work reveals how TNFɑ signaling dynamics can be rewired by a prior infection to shape diverse susceptibilities to future mucosal infections.


Asunto(s)
Inmunidad Mucosa , Factores Inmunológicos/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Infecciones Urinarias/inmunología , Animales , Modelos Animales de Enfermedad , Ratones , Recurrencia , Prevención Secundaria
11.
PLoS One ; 14(7): e0219941, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31329630

RESUMEN

Escherichia coli infection of the female reproductive tract is a significant cause of disease in humans and animals, but simple animal models are lacking. Here we report that vaginal inoculation of uropathogenic E. coli strains UTI89 and CFT073 in non-pregnant, estrogen-treated mice resulted in robust colonization of the vagina and uterine horns, whereas titers of the lab strain MG1655 were significantly lower. Non-estrogenized mice also became colonized, but there was more variation in titers. A dose of 104 colony-forming units (CFU) UTI89 was sufficient to result in colonization in all estrogenized mice, and we also observed bacterial transfer between inoculated and uninoculated estrogenized cage mates. UTI89 infection led to inflammation and leukocyte infiltration into the uterine horns as evidenced by tissue histology. Flow cytometry experiments revealed that neutrophil, monocyte and eosinophil populations were significantly increased in infected uterine horns. This model is a simple way to study host-pathogen interactions in E. coli vaginal colonization and uterine infection. There are immediate implications for investigators studying urinary tract infection using mouse models, as few E. coli are required to achieve reproductive colonization, resulting in an additional, underappreciated mucosal reservoir.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Escherichia coli Patógena Extraintestinal/patogenicidad , Enfermedades Uterinas/microbiología , Animales , Recuento de Colonia Microbiana , Infecciones por Escherichia coli/patología , Femenino , Ratones , Ratones Endogámicos C57BL , Enfermedades Uterinas/patología , Útero/microbiología , Útero/patología
12.
Infect Immun ; 87(7)2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31061142

RESUMEN

Half of all humans harbor Helicobacter pylori in their stomachs. Helical cell shape is thought to facilitate H. pylori's ability to bore into the protective mucus layer in a corkscrew-like motion, thereby enhancing colonization of the stomach. H. pylori cell shape mutants show impaired colonization of the mouse stomach, highlighting the importance of cell shape in infection. To gain a deeper understanding of how helical cell morphology promotes host colonization by H. pylori, we used three-dimensional confocal microscopy to visualize the clinical isolate PMSS1 and an isogenic straight-rod mutant (Δcsd6) within thick longitudinal mouse stomach sections. We also performed volumetric image analysis to quantify the number of bacteria residing within corpus and antral glands in addition to measuring total CFU. We found that straight rods show attenuation during acute colonization of the stomach (1 day or 1 week postinfection) as measured by total CFU. Our quantitative imaging revealed that wild-type bacteria extensively colonized antral glands at 1 week postinfection, while csd6 mutants showed variable colonization of the antrum at this time point. During chronic infection (1 or 3 months postinfection), total CFU were highly variable but similar for wild-type and straight rods. Both wild-type and straight rods persisted and expanded in corpus glands during chronic infection. However, the straight rods showed reduced inflammation and disease progression. Thus, helical cell shape contributes to tissue interactions that promote inflammation during chronic infection, in addition to facilitating niche acquisition during acute infection.


Asunto(s)
Infecciones por Helicobacter/microbiología , Helicobacter pylori/citología , Helicobacter pylori/crecimiento & desarrollo , Estómago/patología , Animales , Adhesión Bacteriana , Enfermedad Crónica , Femenino , Infecciones por Helicobacter/patología , Helicobacter pylori/genética , Humanos , Ratones Endogámicos C57BL , Antro Pilórico/microbiología , Antro Pilórico/patología , Estómago/microbiología
13.
PLoS Pathog ; 14(12): e1007457, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30543708

RESUMEN

Urinary tract infections (UTI) are extremely common and can be highly recurrent, with 1-2% of women suffering from six or more recurrent episodes per year. The high incidence of recurrent UTI, including recurrent infections caused by the same bacterial strain that caused the first infection, suggests that at least some women do not mount a protective adaptive immune response to UTI. Here we observed in a mouse model of cystitis (bladder infection) that infection with two different clinical uropathogenic Escherichia coli (UPEC) isolates, UTI89 or CFT073, resulted in different kinetics of bacterial clearance and different susceptibility to same-strain recurrent infection. UTI89 and CFT073 both caused infections that persisted for at least two weeks in similar proportions of mice, but whereas UTI89 infections could persist indefinitely, CFT073 infections began to clear two weeks after inoculation and were uniformly cleared within eight weeks. Mice with a history of CFT073 cystitis lasting four weeks were protected against recurrent CFT073 infection after antibiotic therapy, but were not protected against challenge with UTI89. In contrast, mice with a history of UTI89 cystitis lasting four weeks were highly susceptible to challenge infection with either strain after antibiotic treatment. We found that depletion of CD4+ and CD8+ T cell subsets impaired the ability of the host to clear CFT073 infections and rendered mice with a history of CFT073 cystitis lasting four weeks susceptible to recurrent CFT073 cystitis upon challenge. Our findings demonstrate the complex interplay between the broad genetic diversity of UPEC and the host innate and adaptive immune responses during UTI. A better understanding of these host-pathogen interactions is urgently needed for effective drug and vaccine development in the era of increasing antibiotic resistance.


Asunto(s)
Cistitis/inmunología , Susceptibilidad a Enfermedades/inmunología , Infecciones por Escherichia coli/inmunología , Interacciones Huésped-Patógeno/inmunología , Escherichia coli Uropatógena/inmunología , Animales , Ratones , Escherichia coli Uropatógena/genética
14.
PLoS Pathog ; 13(3): e1006238, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28358889

RESUMEN

Pathogens often inhabit the body asymptomatically, emerging to cause disease in response to unknown triggers. In the bladder, latent intracellular Escherichia coli reservoirs are regarded as likely origins of recurrent urinary tract infection (rUTI), a problem affecting millions of women worldwide. However, clinically plausible triggers that activate these reservoirs are unknown. Clinical studies suggest that the composition of a woman's vaginal microbiota influences her susceptibility to rUTI, but the mechanisms behind these associations are unclear. Several lines of evidence suggest that the urinary tract is routinely exposed to vaginal bacteria, including Gardnerella vaginalis, a dominant member of the vaginal microbiota in some women. Using a mouse model, we show that bladder exposure to G. vaginalis triggers E. coli egress from latent bladder reservoirs and enhances the potential for life-threatening outcomes of the resulting E. coli rUTI. Transient G. vaginalis exposures were sufficient to cause bladder epithelial apoptosis and exfoliation and interleukin-1-receptor-mediated kidney injury, which persisted after G. vaginalis clearance from the urinary tract. These results support a broader view of UTI pathogenesis in which disease can be driven by short-lived but powerful urinary tract exposures to vaginal bacteria that are themselves not "uropathogenic" in the classic sense. This "covert pathogenesis" paradigm may apply to other latent infections, (e.g., tuberculosis), or for diseases currently defined as noninfectious because routine culture fails to detect microbes of recognized significance.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Vejiga Urinaria/microbiología , Infecciones Urinarias/microbiología , Vagina/microbiología , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Gardnerella vaginalis , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Microscopía Electrónica de Rastreo , Escherichia coli Uropatógena
15.
Ann Neurol ; 81(3): 444-453, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28165634

RESUMEN

OBJECTIVE: To determine whether common polymorphisms in CACNA1G, CACNA1H, CACNA1I, and ABCB1 are associated with differential short-term seizure outcome in childhood absence epilepsy (CAE). METHODS: Four hundred forty-six CAE children in a randomized double-blind trial of ethosuximide, lamotrigine, and valproate had short-term seizure outcome determined. Associations between polymorphisms (minor allele frequency ≥ 15%) in 4 genes and seizure outcomes were assessed. In vitro electrophysiology on transfected CACNA1H channels determined impact of 1 variant on T-type calcium channel responsiveness to ethosuximide. RESULTS: Eighty percent (357 of 446) of subjects had informative short-term seizure status (242 seizure free, 115 not seizure free). In ethosuximide subjects, 2 polymorphisms (CACNA1H rs61734410/P640L, CACNA1I rs3747178) appeared more commonly among not-seizure-free participants (p = 0.011, odds ratio [OR] = 2.63, 95% confidence limits [CL] = 1.25-5.56; p = 0.026, OR = 2.38, 95% CL = 1.11-5.00). In lamotrigine subjects, 1 ABCB1 missense polymorphism (rs2032582/S893A; p = 0.015, OR = 2.22, 95% CL = 1.16-4.17) was more common in not-seizure-free participants, and 2 CACNA1H polymorphisms (rs2753326, rs2753325) were more common in seizure-free participants (p = 0.038, OR = 0.52, 95% CL = 0.28-0.96). In valproate subjects, no common polymorphisms were associated with seizure status. In vitro electrophysiological studies showed no effect of the P640L polymorphism on channel physiology in the absence of ethosuximide. Ethosuximide's effect on rate of decay of CaV 3.2 was significantly less for P640L channel compared to wild-type channel. INTERPRETATION: Four T-type calcium channel variants and 1 ABCB1 transporter variant were associated with differential drug response in CAE. The in vivo P640L variant's ethosuximide effect was confirmed by in vitro electrophysiological studies. This suggests that genetic variation plays a role in differential CAE drug response. Ann Neurol 2017;81:444-453.


Asunto(s)
Anticonvulsivantes/farmacología , Canales de Calcio Tipo T/genética , Epilepsia Tipo Ausencia/tratamiento farmacológico , Epilepsia Tipo Ausencia/genética , Evaluación de Resultado en la Atención de Salud , Farmacogenética/métodos , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Niño , Preescolar , Estudios Cruzados , Método Doble Ciego , Electroencefalografía , Epilepsia Tipo Ausencia/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Polimorfismo Genético
16.
Nat Microbiol ; 2: 16196, 2016 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-27798558

RESUMEN

Recurrent bacterial infections are a significant burden worldwide, and prior history of infection is often a significant risk factor for developing new infections. For urinary tract infection (UTI), a history of two or more episodes is an independent risk factor for acute infection. However, mechanistic knowledge of UTI pathogenesis has come almost exclusively from studies in naive mice. Here we show that, in mice, an initial Escherichia coli UTI, whether chronic or self-limiting, leaves a long-lasting molecular imprint on the bladder tissue that alters the pathophysiology of subsequent infections, affecting host susceptibility and disease outcome. In bladders of previously infected versus non-infected, antibiotic-treated mice, we found (1) an altered transcriptome and defects in cell maturation, (2) a remodelled epithelium that confers resistance to intracellular bacterial colonization, and (3) changes to cyclooxygenase-2-dependent inflammation. Furthermore, in mice with a history of chronic UTI, cyclooxygenase-2-dependent inflammation allowed a variety of clinical E. coli isolates to circumvent intracellular colonization resistance and cause severe recurrent UTI, which could be prevented by cyclooxygenase-2 inhibition or vaccination. This work provides mechanistic insight into how a history of infection can impact the risk for developing recurrent infection and has implications for the development of therapeutics for recurrent UTI.


Asunto(s)
Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/fisiopatología , Escherichia coli/aislamiento & purificación , Vejiga Urinaria/microbiología , Infecciones Urinarias/microbiología , Infecciones Urinarias/fisiopatología , Animales , Ciclooxigenasa 2/metabolismo , Modelos Animales de Enfermedad , Epitelio/patología , Perfilación de la Expresión Génica , Inflamación/patología , Ratones , Recurrencia
17.
Microbiol Spectr ; 4(1)2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26999391

RESUMEN

Urinary tract infections (UTI) are among the most common bacterial infections in humans, affecting millions of people every year. UTI cause significant morbidity in women throughout their lifespan, in infant boys, in older men, in individuals with underlying urinary tract abnormalities, and in those that require long-term urethral catheterization, such as patients with spinal cord injuries or incapacitated individuals living in nursing homes. Serious sequelae include frequent recurrences, pyelonephritis with sepsis, renal damage in young children, pre-term birth, and complications of frequent antimicrobial use including high-level antibiotic resistance and Clostridium difficile colitis. Uropathogenic E. coli (UPEC) cause the vast majority of UTI, but less common pathogens such as Enterococcus faecalis and other enterococci frequently take advantage of an abnormal or catheterized urinary tract to cause opportunistic infections. While antibiotic therapy has historically been very successful in controlling UTI, the high rate of recurrence remains a major problem, and many individuals suffer from chronically recurring UTI, requiring long-term prophylactic antibiotic regimens to prevent recurrent UTI. Furthermore, the global emergence of multi-drug resistant UPEC in the past ten years spotlights the need for alternative therapeutic and preventative strategies to combat UTI, including anti-infective drug therapies and vaccines. In this chapter, we review recent advances in the field of UTI pathogenesis, with an emphasis on the identification of promising drug and vaccine targets. We then discuss the development of new UTI drugs and vaccines, highlighting the challenges these approaches face and the need for a greater understanding of urinary tract mucosal immunity.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Bacterianas/prevención & control , Vacunas Bacterianas , Infecciones Urinarias/prevención & control , Animales , Infecciones Bacterianas/tratamiento farmacológico , Humanos , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología
18.
Curr Opin Infect Dis ; 28(1): 97-105, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25517222

RESUMEN

PURPOSE OF REVIEW: Recurrent urinary tract infection (rUTI) is a serious clinical problem, yet effective therapeutic options are limited, especially against multidrug-resistant uropathogens. In this review, we explore the development of a clinically relevant model of rUTI in previously infected mice and review recent developments in bladder innate immunity that may affect susceptibility to rUTI. RECENT FINDINGS: Chronic bladder inflammation during prolonged bacterial cystitis in mice causes bladder mucosal remodelling that sensitizes the host to rUTI. Although constitutive defenses help prevent bacterial colonization of the urinary bladder, once infection occurs, induced cytokine and myeloid cell responses predominate and the balance of immune cell defense and bladder immunopathology is critical for determining disease outcome, in both naïve and experienced mice. In particular, the maintenance of the epithelial barrier appears to be essential for preventing severe infection. SUMMARY: The innate immune response plays a key role in determining susceptibility to rUTI. Future studies should be directed towards understanding how the innate immune response changes as a result of bladder mucosal remodelling in previously infected mice, and validating these findings in human clinical specimens. New therapeutics targeting the immune response should selectively target the induced innate responses that cause bladder immunopathology, while leaving protective defenses intact.


Asunto(s)
Infecciones por Escherichia coli/patología , Escherichia coli/patogenicidad , Membrana Mucosa/patología , Vejiga Urinaria/patología , Infecciones Urinarias/patología , Animales , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Infecciones por Escherichia coli/inmunología , Interacciones Huésped-Patógeno , Humanos , Inmunidad Innata , Ratones , Membrana Mucosa/inmunología , Factores de Tiempo , Vejiga Urinaria/microbiología , Infecciones Urinarias/inmunología , Infecciones Urinarias/microbiología
19.
J Pharmacol Exp Ther ; 347(1): 181-92, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23922447

RESUMEN

The organic cation transporter 1 (OCT1), also known as solute carrier family 22 member 1, is strongly and specifically expressed in the human liver. Here we show that the hepatocyte nuclear factor 1 (HNF1) regulates OCT1 transcription and contributes to the strong, liver-specific expression of OCT1. Bioinformatic analyses revealed strong conservation of HNF1 binding motifs in an evolutionary conserved region (ECR) in intron 1 of the OCT1 gene. Electrophoretic mobility shift and chromatin immunoprecipitation assays confirmed the specific binding of HNF1 to the intron 1 ECR. In reporter gene assays performed in HepG2 cells, the intron 1 ECR increased SV40 promoter activity by 22-fold and OCT1 promoter activity by 13-fold. The increase was reversed when the HNF1 binding sites in the intron 1 ECR were mutated or the endogenous HNF1α expression was downregulated with small interfering RNA. Following HNF1α overexpression in Huh7 cells, the intron 1 ECR increased SV40 promoter activity by 11-fold and OCT1 promoter activity by 6-fold. Without HNF1α overexpression, the increases were only 3- and 2-fold, respectively. Finally, in human liver samples, high HNF1 expression was significantly correlated with high OCT1 expression (r = 0.48, P = 0.002, n = 40). In conclusion, HNF1 is a strong regulator of OCT1 expression. It remains to be determined whether genetic variants, disease conditions, or drugs that affect HNF1 activity may affect the pharmacokinetics and efficacy of OCT1-transported drugs such as morphine, tropisetron, ondansetron, tramadol, and metformin. Beyond OCT1, this study demonstrates the validity and usefulness of interspecies comparisons in the discovery of functionally relevant genomic sequences.


Asunto(s)
Secuencia Conservada/genética , Evolución Molecular , Factor Nuclear 1 del Hepatocito/genética , Intrones/genética , Transportador 1 de Catión Orgánico/biosíntesis , Transportador 1 de Catión Orgánico/genética , Adolescente , Adulto , Anciano , Animales , Bovinos , Niño , Preescolar , Perros , Femenino , Regulación de la Expresión Génica , Células Hep G2 , Hepatocitos/fisiología , Humanos , Macaca mulatta , Masculino , Ratones , Persona de Mediana Edad , Pan troglodytes , Unión Proteica/genética , Ratas , Especificidad de la Especie , Transcripción Genética , Adulto Joven
20.
Glob Adv Health Med ; 2(5): 59-69, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24416696

RESUMEN

The urinary tract is a common site of infection in humans. During pregnancy, urinary tract infection (UTI) is associated with increased risks of maternal and neonatal morbidity and mortality, even when the infection is asymptomatic. By mapping available rates of UTI in pregnancy across different populations, we emphasize this as a problem of global significance. Many countries with high rates of preterm birth and neonatal mortality also have rates of UTI in pregnancy that exceed rates seen in more developed countries. A global analysis of the etiologies of UTI revealed familiar culprits as well as emerging threats. Screening and treatment of UTI have improved birth outcomes in several more developed countries and would likely improve maternal and neonatal health worldwide. However, challenges of implementation in resource-poor settings must be overcome. We review the nature of the barriers occurring at each step of the screening and treatment pipeline and highlight steps necessary to overcome these obstacles. It is our hope that the information compiled here will increase awareness of the global significance of UTI in maternal and neonatal health and embolden governments, nongovernmental organizations, and researchers to do their part to make urine screening and UTI treatment a reality for all pregnant women.


El tracto urinario es un lugar frecuente de infección en los seres humanos. Durante el embarazo, la infección del tracto urinario (ITU) va asociada a un aumento del riesgo de morbilidad y mortalidad maternas y neonatales, incluso cuando la infección es asintomática. Al trazar un mapa de los índices disponibles de ITU durante el embarazo en diferentes poblaciones, subrayamos que se trata de un problema de importancia mundial. Muchos países con elevados índices de nacimientos prematuros y de mortalidad neonatal tienen también índices de ITU durante el embarazo superiores a los que se observan en los países más desarrollados. Un análisis a nivel global de las etiologías de la ITU puso en evidencia responsables ya conocidos, pero también amenazas emergentes. La detección y el tratamiento de la ITU han mejorado los resultados de los partos en varios de los países más desarrollados, y probablemente mejorarán en todo el mundo la salud materna y neonatal. Sin embargo, se han de superar los retos que plantea la puesta en práctica en entornos con bajos recursos. Revisamos la naturaleza de las barreras que aparecen en cada etapa del desarrollo de la detección y el tratamiento, y destacamos los pasos necesarios para vencer esos obstáculos. Tenemos la esperanza de que la información que aquí hemos reunido aumentará la conciencia de la importancia a nivel mundial de la ITU en la salud materna y neonatal, y animará a los gobiernos, las organizaciones no gubernamentales y los investigadores a poner de su parte para que la detección en la orina y el tratamiento de la ITU sean una realidad para todas las mujeres embarazadas.

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