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Microglia are brain-resident macrophages that shape neural circuit development and are implicated in neurodevelopmental diseases. Multiple microglial transcriptional states have been defined, but their functional significance is unclear. Here, we identify a type I interferon (IFN-I)-responsive microglial state in the developing somatosensory cortex (postnatal day 5) that is actively engulfing whole neurons. This population expands during cortical remodeling induced by partial whisker deprivation. Global or microglial-specific loss of the IFN-I receptor resulted in microglia with phagolysosomal dysfunction and an accumulation of neurons with nuclear DNA damage. IFN-I gain of function increased neuronal engulfment by microglia in both mouse and zebrafish and restricted the accumulation of DNA-damaged neurons. Finally, IFN-I deficiency resulted in excess cortical excitatory neurons and tactile hypersensitivity. These data define a role for neuron-engulfing microglia during a critical window of brain development and reveal homeostatic functions of a canonical antiviral signaling pathway in the brain.
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Encéfalo , Interferon Tipo I , Microglia , Animais , Camundongos , Interferon Tipo I/metabolismo , Microglia/metabolismo , Neurônios/metabolismo , Peixe-Zebra , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimentoRESUMO
Synapse remodeling is essential to encode experiences into neuronal circuits. Here, we define a molecular interaction between neurons and microglia that drives experience-dependent synapse remodeling in the hippocampus. We find that the cytokine interleukin-33 (IL-33) is expressed by adult hippocampal neurons in an experience-dependent manner and defines a neuronal subset primed for synaptic plasticity. Loss of neuronal IL-33 or the microglial IL-33 receptor leads to impaired spine plasticity, reduced newborn neuron integration, and diminished precision of remote fear memories. Memory precision and neuronal IL-33 are decreased in aged mice, and IL-33 gain of function mitigates age-related decreases in spine plasticity. We find that neuronal IL-33 instructs microglial engulfment of the extracellular matrix (ECM) and that its loss leads to impaired ECM engulfment and a concomitant accumulation of ECM proteins in contact with synapses. These data define a cellular mechanism through which microglia regulate experience-dependent synapse remodeling and promote memory consolidation.
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Matriz Extracelular/metabolismo , Microglia/fisiologia , Plasticidade Neuronal/fisiologia , Envelhecimento , Animais , Medo , Regulação da Expressão Gênica , Hipocampo/metabolismo , Proteína 1 Semelhante a Receptor de Interleucina-1/genética , Proteína 1 Semelhante a Receptor de Interleucina-1/metabolismo , Interleucina-33/genética , Interleucina-33/metabolismo , Memória , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/metabolismo , Transdução de SinaisRESUMO
The Wnt/ß-catenin pathway contains multiple high-confidence risk genes that are linked to neurodevelopmental disorders, including autism spectrum disorder. However, its ubiquitous roles across brain cell types and developmental stages have made it challenging to define its impact on neural circuit development and behavior. Here, we show that TCF7L2, which is a key transcriptional effector of the Wnt/ß-catenin pathway, plays a cell-autonomous role in postnatal astrocyte maturation and impacts adult social behavior. TCF7L2 was the dominant Wnt effector that was expressed in both mouse and human astrocytes, with a peak during astrocyte maturation. The conditional knockout of Tcf7l2 in postnatal astrocytes led to an enlargement of astrocytes with defective tiling and gap junction coupling. These mice also exhibited an increase in the number of cortical excitatory and inhibitory synapses and a marked increase in social interaction by adulthood. These data reveal an astrocytic role for developmental Wnt/ß-catenin signaling in restricting excitatory synapse numbers and regulating adult social behavior.
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To determine the clinical characteristics of and risk factors for suspected reinfection with coronavirus 2019 (COVID-19). This was a retrospective cohort study using population-based notification records of residents in Kyoto City (1.4 M) with laboratory-confirmed COVID-19 infection between 1 March 2020 and 15 April 2022. Reinfection was defined by two or more positive COVID-19 test results ⧠90 days apart. Demographic characteristics, the route and timing of infection and history of vaccination were analysed to identify risk factors for reinfection. Among the cohort of 107,475 patients, reinfection was identified in 0.66% (n = 709). The age group with the highest reinfection rate was 18-39 years (1.06%), followed by 40-59 years (0.58%). Compared to the medical and nursing professionals, individuals who worked in the construction and manufacturing industry (odds ratio [OR]: 2.86; 95% confidence interval [CI]: 1.66-4.92) and hospitality industry (OR: 2.05; 95% CI: 1.28-.31) were more likely to be reinfected. Symptomatic cases at initial infection, receiving more than 2 doses of vaccination and risk factors for severe infection at initial infection were protective factors against reinfection. Of the reinfected individuals, the reinfection route was unknown in 65%. Reinfection with COVID-19 is uncommon, with suspected reinfections more likely in adults, those with high exposure and unvaccinated individuals; the reinfection route was unknown in the majority of cases. This study confirmed the need to continue with self-protection efforts and to implement vaccination programs in high-risk populations.
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COVID-19 , Reinfecção , Adulto , Humanos , Adolescente , Adulto Jovem , Incidência , Estudos Retrospectivos , COVID-19/epidemiologia , Fatores de RiscoRESUMO
Household transmission is a primary source of SARS-CoV-2 spread. We used COVID-19 epidemiologic investigation data and viral genome analysis data collected in the city of Kyoto, Japan, during January 2020-June 2021 to evaluate the effects of different settings and viral strains on SARS-CoV-2 transmission. Epidemiologic investigations of 5,061 COVID-19 cases found that the most common category for close contact was within households (35.3%); this category also had the highest reverse transcription PCR positivity. The prevalent viral lineage shifted from B.1.1.214 in the third wave to the Alpha variant in the fourth wave. The proportion of secondary cases associated with households also increased from the third to fourth waves (27% vs. 29%). Among 564 contacts from 206 households, Alpha variant was significantly associated with household transmission (odds ratio 1.52, 95% CI 1.06-2.18) compared with B.1.1.214. Public health interventions targeting household contacts and specific variants could help control SARS-CoV-2 transmission.
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COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/transmissão , Busca de Comunicante , Humanos , Japão/epidemiologia , SARS-CoV-2/genéticaRESUMO
AIM: Extraction of the fetal body is typically performed immediately after delivery of the head in Western obstetric care. Reports justifying immediate extraction are few. Two-step delivery entails waiting for the next uterine contraction after delivery of the head. The present study evaluates neonatal asphyxia and respiratory impairment in two-step delivery using the head-to-body delivery interval. METHODS: This prospective observational study performed at a single birth clinic used the data of 262 low-risk pregnant women with two-step delivery. We measured the time interval of head-to-body delivery and correlation analysis and simple linear regression analysis between the head-to-body delivery interval and umbilical artery pH. The women were divided into two groups according to the head-to-body delivery interval: ≤60 or >60 s. The prevalence of neonatal asphyxia and neonatal respiratory impairment was compared between the groups. RESULTS: The mean head-to-body delivery interval was 88.9 ± 71.3 s. The umbilical artery pH tended to decrease with increasing head-to-body delivery interval; however, there was almost no correlation and the decline of pH was only 0.010 for every additional minute. Low Apgar score incidence at 5 min did not differ significantly between the groups. No cases of shoulder dystocia were reported, and tachypnea at 4 h after birth occurred in 3% of the births. CONCLUSIONS: A longer head-to-body delivery interval is not associated with negative outcomes in two-step delivery. We believe that two-step delivery could have some superior outcomes compared with one-step delivery outcomes, particularly as to improving fetal circulation and preventing shoulder dystocia.
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Distocia , Parto Obstétrico , Distocia/epidemiologia , Feminino , Humanos , Recém-Nascido , Parto , Gravidez , Estudos Prospectivos , OmbroRESUMO
INTRODUCTION: To check evidence that symptoms identical with those constituting "underactive bladder" (UAB) and "overactive bladder" (OAB) are caused by apical prolapse and cured by repair thereof. MATERIAL AND METHODS: After repair of apical prolapse by mesh tape reinforcement of lax uterosacral ligaments (USL) data form 1,671 women were retrospectively examined to determine the presence of OAB and UAB symptoms and to check, how many were cured surgically. Thereby 3 different techniques were performed: elevate (n = 277), "Posterior IVS" (n = 1,049), and TFS cardinal (CL)/USL (n = 345). RESULTS: Symptoms identical with those comprising UAB and OAB were cured in up to 80% of cases following surgical repair of the CL/USL complex. CONCLUSIONS: These symptoms may be consistent with symptoms of the posterior fornix syndrome, which comprises 4 main symptoms: micturition difficulties, urge/frequency, nocturia, chronic pelvic pain, all consequent on USL laxity. Surgical cure of OAB and UAB is inconsistent with existing definitions, which imply pathogenesis of the detrusor muscle itself. A reconsideration and reformulation of existing definitions may be required. Altering UAB definition to "bladder emptying difficulties" and return to former definitions for OAB such as "detrusor" or "bladder instability" may help to restore compatibility with surgical cure of these conditions.
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Slings Suburetrais , Bexiga Urinária Hiperativa/cirurgia , Bexiga Inativa/cirurgia , Feminino , Humanos , Indução de Remissão , Estudos Retrospectivos , Terminologia como Assunto , Bexiga Urinária Hiperativa/diagnóstico , Bexiga Urinária Hiperativa/etiologia , Bexiga Inativa/diagnóstico , Bexiga Inativa/etiologia , Procedimentos Cirúrgicos Urológicos/métodosRESUMO
AIM: The ageing population in Japan brings problems of pelvic organ prolapse (POP), bladder and bowel incontinence, and fragility as regards major pelvic surgery. Existing data from tissue fixation system (TFS) surgery show high cure rates for these conditions, but long-term data are lacking. We aimed to elucidate the usefulness of TFS by assessing 5-year postoperative outcomes. METHODS: A total of 68 patients, mean age 70 years, underwent total pelvic floor repair. Cystocele, apical prolapse, and rectocele were variously addressed by TFS repair of pubourethral, arcus tendineus fasciae pelvis, cardinal, uterosacral, and perineal body ligaments using a mean 3.2 tapes per patient (n = 216). Patients were followed up at 12 months then yearly. We included patients with third- or fourth-degree uterine/vaginal prolapse (POP Quantification classification). We excluded patients with serious comorbid conditions. RESULTS: The mean operating time was 88 min and the mean blood loss was 78 mL. There was minimal postoperative pain and urinary retention, as evidenced by a mean hospital stay of 0.8 days and early return to normal activities. The 5-year cure rates for urinary stress incontinence, urgency, nocturia, and frequency were 82%, 91.7%, 58%, and 52%, respectively. The surgical cure rate for POP was 87.1% at 12 months, falling to 79.0 at 60 months. The cumulative 5-year erosion rate was 0% and 1.7% for all ligaments except the perineal body (25.7%), reducing to 2.6% by year 5 following anchor placement into deep transversus perinei. Two cases of ileus were attributed to incorrect technique. CONCLUSION: Reinforcing up to four ligaments with the TFS was sufficient for cure of third- and fourth-degree POP. The technique is minimally invasive, suitable for elderly women, and effective at 5 years for both anatomical and symptom cure.
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Ligamento Largo/cirurgia , Procedimentos Cirúrgicos em Ginecologia/métodos , Avaliação de Resultados em Cuidados de Saúde , Prolapso de Órgão Pélvico/cirurgia , Fixação de Tecidos/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Visceral obesity has been defined as an important element of the metabolic syndrome and contributes to the development of insulin resistance and cardiovascular disease. Increasing endogenous levels of epoxyeicosatrienoic acids (EETs) are known for their analgesic, antihypertensive, and antiinflammatory effects. The availability of EETs is limited primarily by the soluble epoxide hydrolase (sEH, EPHX2), which metabolizes EETs to their less active diols. In this study, we tested the hypothesis that EETs are involved in glucose regulation and in retarding the development of insulin resistance. To address the role of EETs in regulating glucose homeostasis and insulin signaling, we used mice with targeted gene deletion of sEH (Ephx2-null mice) and a subsequent study with a selective sEH inhibitor. When wild-type mice are fed a high fat diet, insulin resistance develops. However, knockout or inhibition of sEH activity resulted in a significant decrease in plasma glucose. These findings are characterized by enhancement of tyrosyl phosphorylation of the insulin receptor, insulin receptor substrate 1, and their downstream cascade. In addition, pancreatic islets were larger when sEH was disrupted. This effect was associated with an increase in vasculature. These observations were supported by pharmacological inhibition of sEH. These data suggest that an increase in EETs due to sEH-gene knockout leads to an increase in the size of islets and improved insulin signaling and sensitivity.
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Epóxido Hidrolases/deficiência , Glucose/metabolismo , Resistência à Insulina , Ilhotas Pancreáticas/citologia , Animais , Ácido Araquidônico/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Epóxido Hidrolases/genética , Epóxido Hidrolases/fisiologia , Homeostase , Insulina/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Obesidade Abdominal , Pâncreas/metabolismo , Transdução de SinaisRESUMO
A 32-year-old woman had bilateral tubal and intrauterine pregnancies after hyperovulation with clomiphene citrate and subsequent artificial insemination with husband's semen. Laparoscopic surgery revealed bilateral tubal pregnancies. Salpingectomy was performed on the left tube and linear salpingotomy was performed on the right tube. The postoperative course was uneventful. The patient delivered a healthy girl vaginally at 39 weeks' gestation. Only eight cases with bilateral and intrauterine pregnancy have been reported. The live birth rate of bilateral tubal pregnancy and intrauterine pregnancy is 60% (6/10), which is similar to that of heterotopic pregnancy. Laparoscopic surgery is effective for confirming the diagnosis and treating heterotopic pregnancy.
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Gravidez Heterotópica/diagnóstico , Gravidez Tubária/diagnóstico , Diagnóstico Pré-Natal , Dor Abdominal/etiologia , Adulto , Feminino , Humanos , Inseminação Artificial Homóloga/efeitos adversos , Laparoscopia/efeitos adversos , Nascido Vivo , Indução da Ovulação/efeitos adversos , Gravidez , Primeiro Trimestre da Gravidez , Gravidez Heterotópica/fisiopatologia , Gravidez Heterotópica/cirurgia , Gravidez Tubária/fisiopatologia , Gravidez Tubária/cirurgia , Prognóstico , Salpingectomia/efeitos adversos , Resultado do TratamentoRESUMO
Descending perineal syndrome (DPS) was described by Parks et al. as descent of the anus on straining, typically 3-4 cm below a line drawn from the coccyx to the lower end of the. DPS is associated with obstructed defecation, with increased bulging of the perineum with straining, although perineal descent can also be seen at rest. In their review, Chaudhry and Tarnay stated: "It is controversial whether surgical management is even an option for patients with DPS". The deep transversus perinei (DTP) ligaments are the suspensory ligaments of the perineal body (PB). DTP are approximately 4 cm long. They attach behind the upper 2/3 and lower 1/3 of the descending ramus. If, at childbirth, the PB is overstretched and displaced laterally and inferiorly, the DTP lengthens. DPS is described as descent of the anus on straining, typically 3-4 cm below a line drawn from the coccyx to the lower end of the symphysis. DPS is associated with obstructed and often, assisted defecation, with increased bulging of the perineum with straining descent of the anus on straining. The surgical methodology begins as a standard PB repair which dissects the rectum from the vagina and PB and approximates the displaced components of the PB. We added an additional step: identifying the DTPs, shortening and reinforcing them with the Tissue Fixation System (TFS) minisling or No. 2 polyester sutures. High cure rates for obstructed defecation were achieved with the TFS minisling, and initial results using No. 2 polyester sutures are favourable. The key messages from both operations is DPS is caused by stretching and elongation of DPS ligaments, and these are surgically repairable.
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The structural basis of the Integral Theory is holistic. Four main pelvic muscles interact holistically with five main pelvic ligaments to maintain pelvic organ structure and function. The vagina is structurally weak. The support it provides to the bladder base is contingent on being stretched by opposite pelvic muscle forces, much like a trampoline. Its main role is to transmit muscle forces to facilitate continence, evacuation and control of urgency. Therefore, as an organ that cannot regenerate, the vagina should be conserved, and not excised. The ligaments provide the main structural support for the organs and are the most vulnerable part of the anatomical system to injury because their structural collagen is depolymerized prior to labour, and stretched during labour. Further ligament weakening occurs after menopause due to collagen breakdown. Hence, collagen loss is the main cause of organ prolapse and lower urinary tract symptoms (LUTS). The strengthening of damaged ligaments, whether surgically or non-surgically, can improve or cure symptoms and prolapse. Because collagen loss in ligaments is a principal cause of dysfunction in older women, collagen-creating techniques are advised: precisely inserted tapes to create neoligaments, or wide-bore No. 2 or No. 3 polyester ligament sutures instead of dissolvable sutures.
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A core concept of the Integral Theory System is that "ligaments are for structure; vagina is for function". The vagina and uterus should be conserved. Because the vagina is an organ, its collagen and elastin, which are so necessary for its function, cannot regenerate once they are removed. Removing the uterus involves severing the descending uterine artery, which is the principal blood supply of the proximal part of the uterosacral ligaments (USLs), and so may cause atrophy, which can cause future incontinence problems because of collagen loss after menopause. The diagnostic algorithm guides which of the five pelvic ligaments need repair. Native ligament plication can be adequate for prolapse/symptom cure, but only in premenopausal women. Postmenopausal women are usually collagen deficient and require collagen-creating tapes or wide-bore polyester sutures to restore structural collagen in the ligaments. Of extreme importance, vaginal tissue excision should be avoided, as consequent scarring may cause "tethered vagina syndrome" (TVS). TVS can cause massive uncontrolled urine loss because the scar tissue in the bladder neck area of the vagina can link the more powerful posterior muscles to the anterior, so the posterior urethra wall is forcibly pulled open, when given the signal to close. Instead of vaginal excision, a "concertina" suture technique re-assigns and shrinks excess vaginal tissue to normal anatomy by 6 weeks. In conclusion, the five key surgical principles of the Integral Theory System are: ligaments are for structure, vagina is for function; structure (prolapse) and function (symptoms) are related; repair the structure and you will restore the function; avoid vaginal excision and hysterectomy; create new collagen to reinforce the damaged ligaments.
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An approach to genetically engineered resistance to pseudorabies virus (PRV) infection was examined by using a mouse model with defined point mutation in primary receptor for alphaherpesviruses, nectin-1, by the CRISPR/Cas9 system. It has become clear that phenylalanine at position 129 of nectin-1 is important for binding to viral glycoprotein D (gD), and mutation of phenylalanine 129 to alanine (F129A) prevents nectin-1 binding to gD and virus entry in vitro. Here, to assess the antiviral potential of the single amino acid mutation of nectin-1, F129A, in vivo, we generated genome-edited mutant mouse lines; F129A and 135 knockout (KO). The latter, 135 KO used as a nectin-1 knockout line for comparison, expresses a carboxy-terminal deleted polypeptide consisting of 135 amino acids without phenylalanine 129. In the challenge with 10 LD50 PRV via intranasal route, perfect protection of disease onset was induced by expression of the mutation of nectin-1, F129A (survival rate: 100% in F129A and 135 KO versus 0% in wild type mice). Neither viral DNA/antigens nor pathological changes were detected in F129A, suggesting that viral entry was prevented at the primary site in natural infection. In the challenge with 50 LD50 PRV, lower but still strong protective effect against disease onset was observed (survival rate: 57% in F129A and 75% in 135 KO versus 0% in wild type mice). The present results indicate that single amino acid mutation of nectin-1 F129A provides significant resistance against lethal pseudorabies.
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Herpesvirus Suídeo 1 , Pseudorraiva , Animais , Camundongos , Aminoácidos/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Mutação , Nectinas/genética , Nectinas/metabolismo , Fenilalanina/genética , Fenilalanina/metabolismo , Pseudorraiva/prevenção & controle , Proteínas do Envelope Viral/genéticaRESUMO
Bacteria are equipped with complex cell surface structures, such as cell walls. How they maintain cell surface integrity through cell wall metabolism during growth and adaptation to unfavorable environmental conditions is still elusive. In the Gram-positive soil bacterium Bacillus subtilis, one extracytoplasmic function (ECF) sigma factor, SigM, is believed to play a primary role in cell surface integrity. Here, we find that expression of CsbB, which is known to be involved in the extracellular stress response, causes constitutive activation of SigM when YfhO, a membrane protein with unknown function, is lost. CsbB has similarity with the well-characterized bactoprenol glucosyltransferase GtrB found in Gram-negative bacteria. Substitution of a single amino acid residue at the putative catalytic site of CsbB abolishes this constitutive activation, and expression of Escherichia coli GtrB in B. subtilis causes similar effects as expression of CsbB, suggesting that SigM is activated by the glycosyltransferase activity of CsbB. A comparison with the Gtr system in Gram-negative bacteria suggests that accumulation of glycosylated bactoprenol catalyzed by CsbB reduces the bactoprenol pool in the absence of YfhO. Reduction of bactoprenol synthesis causes similar effects as expression of CsbB. We propose that it is the shortage of available bactoprenol within a cell that induces SigM activity.
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Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Glicosiltransferases/metabolismo , Terpenos/química , Proteínas de Bactérias/genética , Parede Celular/metabolismo , Deleção de Genes , Biblioteca Gênica , Genes Bacterianos , Glicosiltransferases/genética , Mutação , Fenótipo , Fatores de Tempo , beta-Galactosidase/metabolismoRESUMO
PURPOSE: Renal cell carcinoma often presents asymptomatically and patients are commonly diagnosed at the metastatic stage, when treatment options are limited and survival is poor. Since progression-free survival using current therapy for metastatic renal cell carcinoma is only 1 to 2 years and existing drugs are associated with a high resistance rate, new pharmacological targets are needed. We identified and evaluated the nuclear exporter protein CRM1 as a novel potential therapy for renal cell carcinoma. MATERIALS AND METHODS: We tested the efficacy of the CRM1 inhibitors KPT-185 and 251 in several renal cell carcinoma cell lines and in a renal cell carcinoma xenograft model. Apoptosis and cell cycle arrest were quantified and localization of p53 family proteins was assessed using standard techniques. RESULTS: KPT-185 attenuated CRM1 and showed increased cytotoxicity in renal cell carcinoma cells in vitro with evidence of increased apoptosis as well as cell cycle arrest. KPT-185 caused p53 and p21 to remain primarily in the nucleus in all renal cell carcinoma cell lines, suggesting that the mechanism of action of these compounds depends on tumor suppressor protein localization. Furthermore, when administered orally in a high grade renal cell carcinoma xenograft model, the bioavailable CRM1 inhibitor KPT-251 significantly inhibited tumor growth in vivo with the expected on target effects and no obvious toxicity. CONCLUSIONS: The CRM1 inhibitor protein family is a novel therapeutic target for renal cell carcinoma that deserves further intensive investigation for this and other urological malignancies.
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Acrilatos/farmacologia , Antineoplásicos/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Carioferinas/efeitos dos fármacos , Neoplasias Renais/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Triazóis/farmacologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Linhagem Celular Tumoral/efeitos dos fármacos , Modelos Animais de Doenças , Citometria de Fluxo , Humanos , Immunoblotting , Imuno-Histoquímica , Carioferinas/genética , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Distribuição Aleatória , Receptores Citoplasmáticos e Nucleares/genética , Sensibilidade e Especificidade , Taxa de Sobrevida , Carga Tumoral/efeitos dos fármacos , Proteína Exportina 1RESUMO
The mechanisms underlying the anti-inflammatory and antihypertensive effects of long-chain ω-3 polyunsaturated fatty acids (ω-3 PUFAs) are still unclear. The epoxides of an ω-6 fatty acid, arachidonic acid epoxyeicosatrienoic acids also exhibit antihypertensive and anti-inflammatory effects. Thus, we hypothesized that the major ω-3 PUFAs, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may lower the blood pressure and attenuate renal markers of inflammation through their epoxide metabolites. Here, we supplemented mice with an ω-3 rich diet for 3 weeks in a murine model of angiotensin-II-dependent hypertension. Also, because EPA and DHA epoxides are metabolized by soluble epoxide hydrolase (sEH), we tested the combination of an sEH inhibitor and the ω-3 rich diet. Our results show that ω-3 rich diet in combination with the sEH inhibitor lowered Ang-II, increased the blood pressure, further increased the renal levels of EPA and DHA epoxides, reduced renal markers of inflammation (ie, prostaglandins and MCP-1), downregulated an epithelial sodium channel, and upregulated angiotensin-converting enzyme-2 message and significantly modulated cyclooxygenase and lipoxygenase metabolic pathways. Overall, our findings suggest that epoxides of the ω-3 PUFAs contribute to lowering systolic blood pressure and attenuating inflammation in part by reduced prostaglandins and MCP-1 and by upregulation of angiotensin-converting enzyme-2 in angiotensin-II-dependent hypertension.
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Anti-Inflamatórios não Esteroides/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Suplementos Nutricionais , Modelos Animais de Doenças , Epóxido Hidrolases/antagonistas & inibidores , Ácidos Graxos Ômega-3/uso terapêutico , Hipertensão Renal/dietoterapia , Angiotensina II , Enzima de Conversão de Angiotensina 2 , Animais , Anti-Inflamatórios não Esteroides/metabolismo , Anti-Hipertensivos/metabolismo , Terapia Combinada , Inibidores Enzimáticos/uso terapêutico , Bloqueadores do Canal de Sódio Epitelial/metabolismo , Bloqueadores do Canal de Sódio Epitelial/uso terapêutico , Canais Epiteliais de Sódio/química , Canais Epiteliais de Sódio/metabolismo , Epóxido Hidrolases/química , Epóxido Hidrolases/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Hipertensão Renal/tratamento farmacológico , Hipertensão Renal/imunologia , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/imunologia , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Peptidil Dipeptidase A/biossíntese , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Distribuição Aleatória , SolubilidadeRESUMO
Microglia are critical regulators of brain development that engulf synaptic proteins during postnatal synapse remodeling. However, the mechanisms through which microglia sense the brain environment are not well defined. Here, we characterized the regulatory program downstream of interleukin-33 (IL-33), a cytokine that promotes microglial synapse remodeling. Exposing the developing brain to a supraphysiological dose of IL-33 altered the microglial enhancer landscape and increased binding of stimulus-dependent transcription factors including AP-1/FOS. This induced a gene expression program enriched for the expression of pattern recognition receptors, including the scavenger receptor MARCO. CNS-specific deletion of IL-33 led to increased excitatory/inhibitory synaptic balance, spontaneous absence-like epileptiform activity in juvenile mice, and increased seizure susceptibility in response to chemoconvulsants. We found that MARCO promoted synapse engulfment, and Marco-deficient animals had excess thalamic excitatory synapses and increased seizure susceptibility. Taken together, these data define coordinated epigenetic and functional changes in microglia and uncover pattern recognition receptors as potential regulators of postnatal synaptic refinement.
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Interleucina-33 , Microglia , Animais , Camundongos , Microglia/metabolismo , Interleucina-33/metabolismo , Sinapses/metabolismo , Encéfalo/metabolismo , Convulsões/metabolismo , Camundongos Endogâmicos C57BLRESUMO
Microglia are brain resident phagocytes that can engulf synaptic components and extracellular matrix as well as whole neurons. However, whether there are unique molecular mechanisms that regulate these distinct phagocytic states is unknown. Here we define a molecularly distinct microglial subset whose function is to engulf neurons in the developing brain. We transcriptomically identified a cluster of Type I interferon (IFN-I) responsive microglia that expanded 20-fold in the postnatal day 5 somatosensory cortex after partial whisker deprivation, a stressor that accelerates neural circuit remodeling. In situ, IFN-I responsive microglia were highly phagocytic and actively engulfed whole neurons. Conditional deletion of IFN-I signaling (Ifnar1fl/fl) in microglia but not neurons resulted in dysmorphic microglia with stalled phagocytosis and an accumulation of neurons with double strand DNA breaks, a marker of cell stress. Conversely, exogenous IFN-I was sufficient to drive neuronal engulfment by microglia and restrict the accumulation of damaged neurons. IFN-I deficient mice had excess excitatory neurons in the developing somatosensory cortex as well as tactile hypersensitivity to whisker stimulation. These data define a molecular mechanism through which microglia engulf neurons during a critical window of brain development. More broadly, they reveal key homeostatic roles of a canonical antiviral signaling pathway in brain development.