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1.
Am J Ophthalmol Case Rep ; 36: 102023, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39175931

RESUMO

Purpose: Unexplained vision loss after silicone oil removal is a well-documented but incompletely understood entity for which there is no effective treatment described in the existing literature. We present a case where intensive oral and periocular steroid treatment resulted in significant subjective and objective clinical improvement. Observations: After successful pars plana vitrectomy with silicone oil endotamponade to repair a macula sparing retinal detachment, the patient's best corrected visual acuity was 20/20 with silicone oil in the operative eye. However, seven weeks after uncomplicated combined silicone oil removal and cataract extraction with intraocular lens insertion, best corrected visual acuity was 20/250 with no new ophthalmic pathology to explain the vision loss. After a four week course of oral prednisone and three periocular triamcinolone injections over a period of nine weeks, visual acuity improved to 20/25 -2 in the operative eye. Serial multifocal electroretinography initially showed severely diminished amplitudes but improved markedly over the course of steroid treatment. Conclusions and Importance: Although no effective treatments are described in the existing literature, improvement in visual acuity, visual field, and electroretinogram in this case suggests that intensive steroid treatment (periocular and systemic) may be efficacious in treating unexplained vision loss after silicone oil removal.

2.
bioRxiv ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39211124

RESUMO

Genome-wide association studies have identified SH2B3 as an important non-MHC gene for islet autoimmunity and type 1 diabetes (T1D). In this study, we found a single SH2B3 haplotype significantly associated with increased risk for human T1D, and this haplotype carries the single nucleotide variant rs3184504*T in SH2B3. To better characterize the role of SH2B3 in T1D, we used mouse modeling and found a T cell-intrinsic role for SH2B3 regulating peripheral tolerance. SH2B3 deficiency had minimal effect on TCR signaling or proliferation across antigen doses, yet enhanced cell survival and cytokine signaling including common gamma chain-dependent and interferon-gamma receptor signaling. SH2B3 deficient CD8+T cells showed augmented STAT5-MYC and effector-related gene expression partially reversed with blocking autocrine IL-2 in culture. Using the RIP-mOVA model, we found CD8+ T cells lacking SH2B3 promoted early islet destruction and diabetes without requiring CD4+ T cell help. SH2B3-deficient cells demonstrated increased survival post-transfer compared to control cells despite a similar proliferation profile in the same host. Next, we created a spontaneous NOD .Sh2b3 -/- mouse model and found markedly increased incidence and accelerated T1D across sexes. Collectively, these studies identify SH2B3 as a critical mediator of peripheral T cell tolerance limiting the T cell response to self-antigens. Article Highlights: The rs3184504 polymorphism, encoding a hypomorphic variant of the negative regulator SH2B3, strongly associates with T1D.SH2B3 deficiency results in hypersensitivity to cytokines, including IL-2, in murine CD4+ and CD8+ T cells.SH2B3 deficient CD8+ T cells exhibit a comparable transcriptome to wild-type CD8+ T cells at baseline, but upon antigen stimulation SH2B3 deficient cells upregulate genes characteristic of enhanced JAK/STAT signaling and effector functions.We found a T-cell intrinsic role of SH2B3 leading to severe islet destruction in an adoptive transfer murine T1D model, while global SH2B3 deficiency accelerated spontaneous NOD diabetes across sexes.

3.
Front Cell Dev Biol ; 12: 1442488, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139449

RESUMO

Desmoplastic Small Round Cell Tumor (DSRCT) is a highly aggressive pediatric cancer caused by a reciprocal translocation between chromosomes 11 and 22, leading to the formation of the EWSR1::WT1 oncoprotein. DSRCT presents most commonly in the abdominal and pelvic peritoneum and remains refractory to current treatment regimens which include chemotherapy, radiotherapy, and surgery. As a rare cancer, sample and model availability have been a limiting factor to DSRCT research. However, the establishment of rare tumor banks and novel cell lines have recently propelled critical advances in the understanding of DSRCT biology and the identification of potentially promising targeted therapeutics. Here we review model and dataset availability, current understanding of the EWSR1::WT1 oncogenic mechanism, and promising preclinical therapeutics, some of which are now advancing to clinical trials. We discuss efforts to inhibit critical dependencies including NTRK3, EGFR, and CDK4/6 as well as novel immunotherapy strategies targeting surface markers highly expressed in DSRCT such as B7-H3 or neopeptides either derived from or driven by the fusion oncoprotein. Finally, we discuss the prospect of combination therapies and strategies for prioritizing clinical translation.

4.
J Exp Biol ; 227(20)2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39109475

RESUMO

Animals at early life stages are generally more sensitive to environmental stress than adults. This is especially true of oviparous vertebrates that develop in variable environments with little or no parental care. These organisms regularly experience environmental fluctuations as part of their natural development, but climate change is increasing the frequency and intensity of these events. The developmental plasticity of oviparous vertebrates will therefore play a critical role in determining their future fitness and survival. In this Review, we discuss and compare the phenotypic consequences of chronic developmental hypoxia on the cardiovascular system of oviparous vertebrates. In particular, we focus on species-specific responses, critical windows, thresholds for responses and the interactive effects of other stressors, such as temperature and hypercapnia. Although important progress has been made, our Review identifies knowledge gaps that need to be addressed if we are to fully understand the impact of climate change on the developmental plasticity of the oviparous vertebrate cardiovascular system.


Assuntos
Sistema Cardiovascular , Mudança Climática , Hipóxia , Estresse Fisiológico , Vertebrados , Animais , Hipóxia/fisiopatologia , Vertebrados/fisiologia , Vertebrados/crescimento & desenvolvimento , Sistema Cardiovascular/crescimento & desenvolvimento , Sistema Cardiovascular/fisiopatologia , Oviparidade , Adaptação Fisiológica
6.
Artigo em Inglês | MEDLINE | ID: mdl-39214166

RESUMO

Numerous studies report on the influence of temperature on blood gases in ectothermic vertebrates, but there is merely a cursory understanding of these effects in developing animals. Animals that develop in eggs are at the mercy of environmental temperature and are expected to lack the capacity to regulate gas exchange and may regulate blood gases by means of altered conductance for gas exchange. We, therefore, devised a series of studies to characterize the developmental changes in blood gases when embryonic alligators were exposed to 25, 30 and 35 °C. To determine how blood parameters were impacted by changes in embryonic temperature, blood was sampled from the chorioallantoic membrane artery. The blood in the chorioallantoic membrane artery is a mixture of oxygen-poor and oxygen-rich blood, which based on the embryonic vascular anatomy may reflect blood that perfuses the chemoreceptors of the developing animal. Our findings indicate that following a 48 h exposure to 25 °C or 35 °C, there was a positive relationship between CAM artery blood PO2, PCO2 and glucose. However, blood pH suggests embryonic alligators lack an acute regulatory mechanism for adjusting blood pH.

7.
Hemodial Int ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960867

RESUMO

INTRODUCTION: This study aimed to compare the prevalence of potentially inappropriately prescribed drugs in hemodialysis patients and patients with chronic kidney disease who did not require renal replacement therapy, as well as to identify risk factors associated with potentially inappropriate prescribing. METHODS: The study was designed as a cross-sectional study conducted at the Department of Nephrology, Clinical Center in Nis, Serbia. The patients were divided into two groups: (1) patients on hemodialysis treatment and (2) patients with various degrees of chronic kidney disease without renal replacement therapy. The presence or absence of potentially inappropriate prescribing was determined using the 2015 AGS Beers criteria. FINDINGS: The study included a total of 218 patients aged 65 years and over. The number of patients with potentially inappropriate prescribed drugs did not differ significantly (chi-square = 0.000, p = 1.000) between patients on hemodialysis (27 of 83, i.e., 32.5%) and patients with various degrees of chronic kidney disease without renal replacement therapy (44 of 135, i.e., 32.6%). Factors associated with potentially inappropriate prescribing in hemodialysis patients were the number of drugs (hazard ratio [HR] = 1.919, 95% confidence interval [CI]: 1.325-2.780) and number of comorbidities (HR = 1.743, 95% CI: 1.109-2.740). The number of drugs (HR = 1.438, 95% CI: 1.191-1.736) was the only independent factor associated with increased risk of potentially inappropriate prescribing in patients without renal replacement therapy. DISCUSSION: Our study showed that potentially inappropriate prescribing is a relatively frequent phenomenon present in about a third of patients in both study groups. The number of prescribed drugs was the main factor associated with the increased risk of potentially inappropriate prescribing in both groups.

8.
Cancer Res ; 84(9): 1426-1442, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38588409

RESUMO

Desmoplastic small round cell tumors (DSRCT) are a type of aggressive, pediatric sarcoma characterized by the EWSR1::WT1 fusion oncogene. Targeted therapies for DSRCT have not been developed, and standard multimodal therapy is insufficient, leading to a 5-year survival rate of only 15% to 25%. Here, we depleted EWSR1::WT1 in DSRCT and established its essentiality in vivo. Transcriptomic analysis revealed that EWSR1::WT1 induces unique transcriptional alterations compared with WT1 and other fusion oncoproteins and that EWSR1::WT1 binding directly mediates gene upregulation. The E-KTS isoform of EWSR1::WT1 played a dominant role in transcription, and it bound to the CCND1 promoter and stimulated DSRCT growth through the cyclin D-CDK4/6-RB axis. Treatment with the CDK4/6 inhibitor palbociclib successfully reduced growth in two DSRCT xenograft models. As palbociclib has been approved by the FDA for the treatment of breast cancer, these findings demonstrate the sensitivity of DSRCT to palbociclib and support immediate clinical investigation of palbociclib for treating this aggressive pediatric cancer. SIGNIFICANCE: EWSR1::WT1 is essential for desmoplastic small round cell tumors and upregulates the cyclin D-CDK4/6-RB axis that can be targeted with palbociclib, providing a targeted therapeutic strategy for treating this deadly tumor type.


Assuntos
Quinase 4 Dependente de Ciclina , Quinase 6 Dependente de Ciclina , Tumor Desmoplásico de Pequenas Células Redondas , Proteínas de Fusão Oncogênica , Piperazinas , Piridinas , Proteína EWS de Ligação a RNA , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/genética , Tumor Desmoplásico de Pequenas Células Redondas/genética , Tumor Desmoplásico de Pequenas Células Redondas/tratamento farmacológico , Tumor Desmoplásico de Pequenas Células Redondas/patologia , Tumor Desmoplásico de Pequenas Células Redondas/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Proteína EWS de Ligação a RNA/genética , Proteína EWS de Ligação a RNA/metabolismo , Proteínas WT1/genética , Proteínas WT1/metabolismo , Camundongos Endogâmicos NOD
10.
Breastfeed Med ; 19(5): 368-377, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38506260

RESUMO

Background: In the United States, 11.1% of households experience food insecurity; however, pregnant women are disproportionately affected. Maternal food insecurity may affect infant feeding practices, for example, through being a source of chronic stress that may alter the decision to initiate and continue breastfeeding. Thus, we sought to determine whether prenatal food insecurity was associated with breastfeeding (versus not) and exclusive breastfeeding duration among Oregon women. Method: The Oregon Pregnancy Risk Assessment Monitoring System (PRAMS) data of live births from 2008 to 2015 and the Oregon PRAMS-2 follow-up survey were used (n = 3,624) in this study. Associations with breastfeeding initiation and duration were modeled with multivariable logistic regression and accelerated failure time (AFT), respectively. Models were adjusted for maternal sociodemographic and pre-pregnancy health characteristics. Results: Nearly 10% of women experienced prenatal food insecurity. For breastfeeding initiation, unadjusted models suggested non-significant decreased odds (odds ratio (OR) 0.88 [confidence intervals (CI): 0.39, 1.99]), whereas adjusted models revealed a non-significant increased odds (OR 1.41 [CI: 0.58, 3.47]). Unadjusted AFT models suggested that food-insecure mothers had a non-significant decrease in exclusive breastfeeding duration (OR 0.76 [CI: 0.50, 1.17]), but adjustment for covariates attenuated results (OR 0.89 [CI: 0.57, 1.39]). Conclusions: Findings suggest minimal differences in breastfeeding practices when exploring food security status in the prenatal period, though the persistence of food insecurity may affect exclusive breastfeeding duration. Lower breastfeeding initiation may be due to other explanatory factors correlated with food insecurity and breastfeeding, such as education and marital status.


Assuntos
Aleitamento Materno , Insegurança Alimentar , Humanos , Feminino , Aleitamento Materno/estatística & dados numéricos , Oregon/epidemiologia , Adulto , Gravidez , Estudos Longitudinais , Recém-Nascido , Adulto Jovem , Fatores de Tempo , Mães/estatística & dados numéricos , Mães/psicologia , Lactente , Modelos Logísticos
11.
Sci Rep ; 14(1): 4919, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418502

RESUMO

Flat hydrodynamic shells likely represent an evolutionary trade-off between adaptation to an aquatic lifestyle and the instability of more rounded shells, thought beneficial for self-righting. Trade-offs often result in compromises, this is particularly true when freshwater turtles, with flatter shells, must self-right to avoid the negative effects of inverting. These turtles, theoretically, invest more biomechanical effort to achieve successful and timely self-righting when compared to turtles with rounded carapaces. This increase in effort places these hatchlings in a precarious position; prone to inversion and predation and with shells seemingly maladapted to the act of self-righting. Here, we examine hatchling self-righting performance in three morphologically distinct freshwater turtle species (Apalone spinifera, Chelydra serpentina and Trachemys scripta scripta) that inhabit similar environmental niches. We demonstrate that these hatchlings were capable of rapid self-righting and used considerably less biomechanical effort relative to adult turtles. Despite differences in shell morphology the energetic efficiency of self-righting remained remarkably low and uniform between the three species. Our results confound theoretical predictions of self-righting ability based on shell shape metrics and indicate that other morphological characteristics like neck or tail morphology and shell material properties must be considered to better understand the biomechanical nuances of Testudine self-righting.


Assuntos
Tartarugas , Animais , Tartarugas/anatomia & histologia , Evolução Biológica , Exoesqueleto/anatomia & histologia , Água Doce , Hidrodinâmica
12.
Artigo em Inglês | MEDLINE | ID: mdl-38220129

RESUMO

The baroreflex involves cardiovascular homeostatic mechanisms that buffer the system against acute deviations in arterial blood pressure. It is comprised of the cardiac limb which involves adjustments in heart rate and the peripheral limb which involves adjustments in vascular resistance. This negative feedback loop mechanism has been investigated in numerous species of adult vertebrates, however our understanding of the maturation and functional importance of the reflex in developing animals remains poorly understood. In egglaying species, our knowledge of this mechanism is limited to the domestic chicken embryo and the embryonic alligator. While each of these species possess a cardiac baroreflex prior to hatching, they differ in the timing when it becomes functional, with the embryonic chicken possessing the reflex at 90% of incubation, while the alligator possesses the reflex at 70% of incubation. In an effort to determine if bird species might share similar patterns of active baroreflex function, we studied embryonic emus (Dromiceius novaehollandiae). However, we hypothesized that emus would possess a pattern of baroreflex function similar to that of the American alligator given the emu embryo possesses functional vagal tone at 70% of incubation, possibly indicating a more mature collection of cardiovascular control mechanism than those found in embryonic chickens. Our findings illustrate that emu embryos possess a hypotensive baroreflex at 90% of incubation. Therefore, our data fail to support our original hypothesis. While only two species of birds have been studied in this context, it could indicate that baroreflex function is not essential for cardiovascular homeostasis in birds for the majority of in ovo development.


Assuntos
Sistema Cardiovascular , Dromaiidae , Embrião de Galinha , Animais , Barorreflexo/fisiologia , Galinhas , Pressão Arterial , Frequência Cardíaca/fisiologia , Pressão Sanguínea/fisiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-38220130

RESUMO

Assessments of arterial and venous blood gases are required to understand the function of respiratory organs in animals at different stages of development. We measured blood gases in the arteries entering and veins leaving the chorioallantoic membrane (CAM) in embryonic alligators (Alligator mississippiensis). The CAM accounts for virtually all gas exchange in these animals, and we hypothesized that the CAM vasculature would be larger in eggs incubated in hypoxia (10% O2 for 50% or 70% of incubation), which would be reflected in a lower partial pressure of CO2 (PCO2). Contrary to this hypothesis, our measurements revealed no effects of hypoxic incubation on PCO2, and seemingly no increase in vascularization of the CAM in response to incubation in 10% O2. PCO2 was lower on the venous side, but only significantly different from arterial blood at 70% of incubation. The calculated blood flow to the CAM increased with development and was lower in both groups of alligators that had been incubated in hypoxia. Future studies should include measurements of blood parameters taken from embryos held in conditions that mirror incubation O2 levels, in combination with direct measurements of CAM artery blood flow.


Assuntos
Jacarés e Crocodilos , Membrana Corioalantoide , Animais , Gases , Artérias , Hipóxia
14.
Oncogenesis ; 13(1): 2, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177125

RESUMO

Desmoplastic small round cell tumor (DSRCT) is an aggressive pediatric cancer caused by the EWSR1-WT1 fusion oncoprotein. The tumor is refractory to treatment with a 5-year survival rate of only 15-25%, necessitating the development of novel therapeutics, especially those able to target chemoresistant subpopulations. Novel in vitro cancer stem cell-like (CSC-like) culture conditions increase the expression of stemness markers (SOX2, NANOG) and reduce DSRCT cell line susceptibility to chemotherapy while maintaining the ability of DSRCT cells to form xenografts. To gain insights into this chemoresistant model, RNA-seq was performed to elucidate transcriptional alterations between DSRCT cells grown in CSC-like spheres and normal 2-dimensional adherent state. Commonly upregulated and downregulated genes were identified and utilized in pathway analysis revealing upregulation of pathways related to chromatin assembly and disassembly and downregulation of pathways including cell junction assembly and extracellular matrix organization. Alterations in chromatin assembly suggest a role for epigenetics in the DSRCT CSC-like state, which was further investigated with ATAC-seq, identifying over 10,000 differentially accessible peaks, including 4444 sphere accessible peaks and 6,120 adherent accessible peaks. Accessible regions were associated with higher gene expression, including increased accessibility of the CSC marker SOX2 in CSC-like culture conditions. These analyses were further utilized to identify potential CSC therapeutic targets, leading to the identification of B-lymphocyte kinase (BLK) as a CSC-enriched, EWSR1-WT1-regulated, druggable target. BLK inhibition and knockdown reduced CSC-like properties, including abrogation of tumorsphere formation and stemness marker expression. Importantly, BLK knockdown reduced DSRCT CSC-like cell chemoresistance, making its inhibition a promising target for future combination therapy.

15.
Folia Morphol (Warsz) ; 83(1): 215-220, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-36688406

RESUMO

A 77-year-old female cadaver was observed to have a rare branching pattern of the right axillary artery (AA). The first part of the AA typically gives off only a superior thoracic artery (STA) but was observed to give off three branches in the case: a lateral thoracic artery (LTA), a thoracoacromial trunk, and a large common trunk (CT). The LTA travelled to provide a variant STA to the 1st and 2nd intercostal spaces. The CT provided an accessory LTA and accessory thoracodorsal artery before bifurcating into a subscapular artery (SA) and posterior humeral circumflex artery. As expected, the SA further divided into the circumflex scapular artery and thoracodorsal artery. A pectoral artery and the anterior humeral circumflex artery originated directly from the second and third parts of the AA, respectively. Knowledge of AA branching variations is of great clinical significance to anatomists, radiologists, and surgeons due to the high rate of injury to this artery.


Assuntos
Braço , Artéria Axilar , Feminino , Humanos , Idoso , Úmero , Cadáver , Conhecimento
16.
J Intern Med ; 295(3): 346-356, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38011942

RESUMO

BACKGROUND: Choline acetyltransferase (ChAT) is required for the biosynthesis of acetylcholine, the molecular mediator that inhibits cytokine production in the cholinergic anti-inflammatory pathway of the vagus nerve inflammatory reflex. Abundant work has established the biology of cytoplasmic ChAT in neurons, but much less is known about the potential presence and function of ChAT in the extracellular milieu. OBJECTIVES: We evaluated the hypothesis that extracellular ChAT activity responds to inflammation and serves to inhibit cytokine release and attenuate inflammation. METHODS: After developing novel methods for quantification of ChAT activity in plasma, we determined whether ChAT activity changes in response to inflammatory challenges. RESULTS: Active ChAT circulates within the plasma compartment of mice and responds to immunological perturbations. Following the administration of bacterial endotoxin, plasma ChAT activity increases for 12-48 h, a time period that coincides with declining tumor necrosis factor (TNF) levels. Further, a direct activation of the cholinergic anti-inflammatory pathway by vagus nerve stimulation significantly increases plasma ChAT activity, whereas the administration of bioactive recombinant ChAT (r-ChAT) inhibits endotoxin-stimulated TNF production and anti-ChAT antibodies exacerbate endotoxin-induced TNF levels, results of which suggest that ChAT activity regulates endogenous TNF production. Administration of r-ChAT significantly attenuates pro-inflammatory cytokine production and disease activity in the dextran sodium sulfate preclinical model of inflammatory bowel disease. Finally, plasma ChAT levels are also elevated in humans with sepsis, with the highest levels observed in a patient who succumbed to infection. CONCLUSION: As a group, these results support further investigation of ChAT as a counter-regulator of inflammation and potential therapeutic agent.


Assuntos
Acetilcolina , Colina O-Acetiltransferase , Humanos , Colina O-Acetiltransferase/metabolismo , Inflamação , Fator de Necrose Tumoral alfa/metabolismo , Citocinas , Endotoxinas
17.
J Med Chem ; 66(24): 17086-17104, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-38079537

RESUMO

A set of focused analogues have been generated around a lead indirect adenosine monophosphate-activated kinase (AMPK) activator to improve the rat clearance of the molecule. Analogues were focused on inhibiting amide hydrolysis by the strategic placement of substituents that increased the steric environment about the secondary amide bond between 4-aminopiperidine and pyridine-5-carboxylic acid. It was found that placing substituents at position 3 of the piperidine ring and position 4 of the pyridine could all improve clearance without significantly impacting on-target potency. Notably, trans-3-fluoropiperidine 32 reduced rat clearance from above liver blood flow to 19 mL/min/kg and improved the hERG profile by attenuating the basicity of the piperidine moiety. Oral dosing of 32 activated AMPK in mouse liver and after 2 weeks of dosing improved glucose handling in a db/db mouse model of Type II diabetes as well as lowering fasted glucose and insulin levels.


Assuntos
Diabetes Mellitus Tipo 2 , Camundongos , Ratos , Animais , Proteínas Quinases Ativadas por AMP , Diamida , Glucose , Piridinas/farmacologia , Piperidinas , Amidas
18.
Mol Med ; 29(1): 149, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907853

RESUMO

BACKGROUND: Acute pancreatitis is a common and serious inflammatory condition currently lacking disease modifying therapy. The cholinergic anti-inflammatory pathway (CAP) is a potent protective anti-inflammatory response activated by vagus nerve-dependent α7 nicotinic acetylcholine receptor (α7nAChR) signaling using splenic CD4+ T cells as an intermediate. Activating the CAP ameliorates experimental acute pancreatitis. Galantamine is an acetylcholinesterase inhibitor (AChEI) which amplifies the CAP via modulation of central muscarinic ACh receptors (mAChRs). However, as mAChRs also activate pancreatitis, it is currently unknown whether galantamine would be beneficial in acute pancreatitis. METHODS: The effect of galantamine (1-6 mg/kg-body weight) on caerulein-induced acute pancreatitis was evaluated in mice. Two hours following 6 hourly doses of caerulein (50 µg/kg-body weight), organ and serum analyses were performed with accompanying pancreatic histology. Experiments utilizing vagotomy, gene knock out (KO) technology and the use of nAChR antagonists were also performed. RESULTS: Galantamine attenuated pancreatic histologic injury which was mirrored by a reduction in serum amylase and pancreatic inflammatory cytokines and an increase the anti-inflammatory cytokine IL-10 in the serum. These beneficial effects were not altered by bilateral subdiaphragmatic vagotomy, KO of either choline acetyltransferase+ T cells or α7nAChR, or administration of the nAChR ganglionic blocker mecamylamine or the more selective α7nAChR antagonist methyllycaconitine. CONCLUSION: Galantamine improves acute pancreatitis via a mechanism which does not involve previously established physiological and molecular components of the CAP. As galantamine is an approved drug in widespread clinical use with an excellent safety record, our findings are of interest for further evaluating the potential benefits of this drug in patients with acute pancreatitis.


Assuntos
Galantamina , Pancreatite , Humanos , Camundongos , Animais , Galantamina/farmacologia , Galantamina/uso terapêutico , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Acetilcolinesterase/metabolismo , Acetilcolinesterase/uso terapêutico , Ceruletídeo/metabolismo , Ceruletídeo/uso terapêutico , Doença Aguda , Pancreatite/tratamento farmacológico , Pancreatite/patologia , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Peso Corporal
19.
Proc Biol Sci ; 290(2006): 20231353, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37700647

RESUMO

In hypoxia, air-breathing fish obtain O2 from the air but continue to excrete CO2 into the water. Consequently, it is believed that some O2 obtained by air-breathing is lost at the gills in hypoxic water. Pangasionodon hypophthalmus is an air-breathing catfish with very large gills from the Mekong River basin where it is cultured in hypoxic ponds. To understand how P. hypophthalmus can maintain high growth in hypoxia with the presumed O2 loss, we quantified respiratory gas exchange in air and water. In severe hypoxia (PO2: ≈ 1.5 mmHg), it lost a mere 4.9% of its aerial O2 uptake, while maintaining aquatic CO2 excretion at 91% of the total. Further, even small elevations in water PO2 rapidly reduced this minor loss. Charting the cardiovascular bauplan across the branchial basket showed four ventral aortas leaving the bulbus arteriosus, with the first and second gill arches draining into the dorsal aorta while the third and fourth gill arches drain into the coeliacomesenteric artery supplying the gut and the highly trabeculated respiratory swim-bladder. Substantial flow changes across these two arterial systems from normoxic to hypoxic water were not found. We conclude that the proposed branchial oxygen loss in air-breathing fish is likely only a minor inefficiency.


Assuntos
Peixes-Gato , Oxigênio , Animais , Dióxido de Carbono , Hipóxia/veterinária , Transporte Biológico
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