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1.
Eur J Immunol ; 54(6): e2350643, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38581085

RESUMEN

We implicate a phenotype of trained immunity in bone-marrow-derived macrophages in the onset and progression of type 1 diabetes in nonobese diabetic mice. Treatment with FhHDM-1 reversed immune training, reducing histone methylation and glycolysis, and decreasing proinflammatory cytokine production to the same level as macrophages from nondiabetic immune-competent BALB/c mice.


Asunto(s)
Macrófagos , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Animales , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Diabetes Mellitus Tipo 1/inmunología , Citocinas/metabolismo , Fenotipo , Glucólisis , Histonas/metabolismo , Histonas/inmunología , Inflamación/inmunología
2.
J Exp Child Psychol ; 241: 105878, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38354446

RESUMEN

Adults represent the near future more concretely and vividly than the distant future, with important implications for future-oriented behavior (e.g., planning, self-control). Although children are adept at describing future events at around 5 years of age, we know little about how temporal distance (i.e., "near" vs "distant") affects their future event representations. In a series of three experiments, we sought to determine the effects of temporal distance, age, and event frequency on children's future event representations. Participants, 5- to 9-year-olds, were asked to describe frequent (e.g., snack) and infrequent (e.g., party) events, with half of children imagining that these events would happen in the near future and the other half imagining that they would happen in the distant future. We investigated the effect of temporal distance on numerous event representation indicators (e.g., clarity, details, pronouns), all theoretically grounded in previous literature. Although children perceived near events as closer in time than distant events (Experiments 2 and 2b) and temporal distance affected the clarity of event representations (Experiment 2), most indicators were not affected by temporal distance. In contrast, event frequency (examined in Experiment 1) played an important role in children's event representations, with infrequent events being described more concretely than frequent events. Results suggest that young children may begin perceiving differences in temporal distance but that this does not translate to their event representations (e.g., clarity, pronouns) until later in development. Implications for children's future thinking and future research are discussed.


Asunto(s)
Lenguaje , Adulto , Niño , Humanos , Preescolar , Tiempo , Predicción
3.
Parasitology ; 149(10): 1364-1373, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35621040

RESUMEN

The food-borne trematodes, Opisthorchis viverrini and Clonorchis sinensis, are classified as group 1 biological carcinogens: definitive causes of cancer. By contrast, infections with Fasciola hepatica, also a food-borne trematode of the phylum Platyhelminthes, are not carcinogenic. This review explores the premise that the differential activation of macrophages during infection with these food-borne trematodes is a major determinant of the pathological outcome of infection. Like most helminths, the latter stages of infection with all 3 flukes induce M2 macrophages, a phenotype that mediates the functional repair of tissue damaged by the feeding and migratory activities of the parasites. However, there is a critical difference in how the development of pro-inflammatory M1 macrophages is regulated during infection with these parasites. While the activation of the M1 macrophage phenotype is largely suppressed during the early stages of infection with F. hepatica, M1 macrophages predominate in the bile ducts following infection with O. viverrini and C. sinensis. The anti-microbial factors released by M1 macrophages create an environment conducive to mutagenesis, and hence the initiation of tumour formation. Subsequently, the tissue remodelling processes induced by the M2 macrophages promote the proliferation of mutated cells, and the expansion of cancerous tissue. This review will also explore the interactions between macrophages and parasite-derived signals, and their contributions to the stark differences in the innate immune responses to infection with these parasites.


Asunto(s)
Clonorchis sinensis , Fasciola hepatica , Fascioliasis , Opisthorchis , Parásitos , Animales , Fasciola hepatica/genética , Macrófagos , Opisthorchis/genética
4.
Dev Neurosci ; 43(1): 18-26, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33789288

RESUMEN

It has been reported that children may respond better than adults to a spinal cord injury (SCI) of similar severity. There are known biomechanical differences in the developing spinal cord that may contribute to this "infant lesion effect," but the underlying mechanisms are unknown. Using immunohistochemistry, we have previously demonstrated a different injury progression and immune cell response after a mild thoracic contusion SCI in infant rats, as compared to adult rats. Here, we investigated the acute inflammatory responses using flow cytometry and ELISA at 1 h, 24 h, and 1 week after SCI in neonatal (P7) and adult (9 weeks) rats, and locomotor recovery was examined for 6 weeks after injury. Adult rats exhibited a pronounced pro-inflammatory response characterized by neutrophils and M1-like macrophage infiltration and Th1 cytokine secretion. Neonatal rats exhibited a decreased pro-inflammatory response characterized by a higher proportion of M2-like macrophages and reduced Th1 cytokine responses, as compared to adults. These results suggest that the initial inflammatory response to SCI is predominantly anti-inflammatory in very young animals.


Asunto(s)
Traumatismos de la Médula Espinal , Animales , Animales Recién Nacidos , Antiinflamatorios/uso terapéutico , Macrófagos , Ratas , Recuperación de la Función , Médula Espinal , Traumatismos de la Médula Espinal/tratamiento farmacológico
5.
J Exp Child Psychol ; 192: 104767, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31887485

RESUMEN

Increasing psychological distance is an established method for improving children's performance in a number of self-regulation tasks. For example, using a delay of gratification (DoG) task, Prencipe and Zelazo (Psychological Science, 2005, Vol. 16, pp. 501-505) showed that 3-year-olds delay more for "other" than they do for "self," whereas 4-year-olds make similar choices for self and other. However, to our knowledge, no work has manipulated language to increase psychological distance in children. In two experiments, we sought to manipulate psychological distance by replicating Prencipe and Zelazo's age-related findings and extending them to older children (Experiment 1) and also sought to manipulate psychological distance using the auxiliary verbs "want" and "should" to prime more impulsive preference-based decisions or more normative optimal decisions (Experiment 2). In Experiment 1, 96 3- to 7-year-olds showed age-related improvements and interactive effects between age and perspective on DoG performance. In Experiment 2, 132 3- to 7-year-olds showed age-related improvements and a marginal interaction between age and perspective on DoG performance, but no effect of auxiliary verbs was detected. Results are discussed in terms of differing developmental trajectories of DoG for self and other due to psychological distancing, and how taking another's perspective may boost DoG in younger children but not older children.


Asunto(s)
Desarrollo Infantil/fisiología , Descuento por Demora/fisiología , Lenguaje , Adolescente , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Masculino
6.
Behav Brain Sci ; 43: e140, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32645798

RESUMEN

Gilead et al.'s theory presupposes that traversing temporal, spatial, social, and hypothetical distances are largely interchangeable acts of mental travel that co-occur in human ontogeny. Yet, this claim is at odds with recent developmental data suggesting that children's reasoning is differentially affected by the dimension which they must traverse, and that different representational abilities underlie travel across different dimensions.


Asunto(s)
Psicología del Desarrollo , Encéfalo , Niño , Humanos , Solución de Problemas
7.
J Gene Med ; 20(5): e3017, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29578255

RESUMEN

BACKGROUND: Gene therapy is one treatment that may ultimately cure type 1 diabetes. We have previously shown that the introduction of furin-cleavable human insulin (INS-FUR) to the livers in several animal models of diabetes resulted in the reversal of diabetes and partial pancreatic transdifferentiation of liver cells. The present study investigated whether streptozotocin-diabetes could be reversed in FRG mice in which chimeric mouse-human livers can readily be established and, in addition, whether pancreatic transdifferentiation occurred in the engrafted human hepatocytes. METHODS: Engraftment of human hepatocytes was confirmed by measuring human albumin levels. Following delivery of the empty vector or the INS-FUR vector to diabetic FRG mice, mice were monitored for weight and blood glucose levels. Intraperitoneal glucose tolerance tests (IPGTTs) were performed. Expression levels of pancreatic hormones and transcription factors were determined by a reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry. RESULTS: Diabetes was reversed for a period of 60 days (experimental endpoint) after transduction with INS-FUR. IPGTTs of the insulin-transduced animals were not significantly different from nondiabetic animals. Immunofluorescence microscopy revealed the expression of human albumin and insulin in transduced liver samples. Quantitative RT-PCR showed expression of human and mouse endocrine hormones and ß-cell transcription factors, indicating partial pancreatic transdifferentiation of mouse and human hepatocytes. Nonfasting human C-peptide levels were significantly higher than mouse levels, suggesting that transdifferentiated human hepatocytes made a significant contribution to the reversal of diabetes. CONCLUSIONS: These data show that human hepatocytes can be induced to undergo partial pancreatic transdifferentiation in vivo, indicating that the technology holds promise for the treatment of type 1 diabetes.


Asunto(s)
Transdiferenciación Celular/genética , Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Hepatocitos/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Hígado/metabolismo , Animales , Trasplante de Células/métodos , Células Cultivadas , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Tipo 1/genética , Modelos Animales de Enfermedad , Hepatocitos/citología , Humanos , Insulina/genética , Células Secretoras de Insulina/citología , Lentivirus/genética , Hígado/citología , Ratones , Trasplante Heterólogo
8.
FASEB J ; 31(1): 85-95, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27682204

RESUMEN

The NLRP3 inflammasome is a multimeric protein complex that controls the production of IL-1ß, a cytokine that influences the development of both innate and adaptive immune responses. Helminth parasites secrete molecules that interact with innate immune cells, modulating their activity to ultimately determine the phenotype of differentiated T cells, thus creating an immune environment that is conducive to sustaining chronic infection. We show that one of these molecules, FhHDM-1, a cathelicidin-like peptide secreted by the helminth parasite, Fasciola hepatica, inhibits the activation of the NLRP3 inflammasome resulting in reduced secretion of IL-1ß by macrophages. FhHDM-1 had no effect on the synthesis of pro-IL-1ß. Rather, the inhibitory effect was associated with the capacity of the peptide to prevent acidification of the endolysosome. The activation of cathepsin B protease by lysosomal destabilization was prevented in FhHDM-1-treated macrophages. By contrast, peptide derivatives of FhHDM-1 that did not alter the lysosomal pH did not inhibit secretion of IL-1ß. We propose a novel immune modulatory strategy used by F. hepatica, whereby secretion of the FhHDM-1 peptide impairs the activation of NLRP3 by lysosomal cathepsin B protease, which prevents the downstream production of IL-1ß and the development of protective T helper 1 type immune responses that are detrimental to parasite survival.-Alvarado, R., To, J., Lund, M. E., Pinar, A., Mansell, A., Robinson, M. W., O'Brien, B. A., Dalton, J. P., Donnelly, S. The immune modulatory peptide FhHDM-1 secreted by the helminth Fasciola hepatica prevents NLRP3 inflammasome activation by inhibiting endolysosomal acidification in macrophages.


Asunto(s)
Fasciola hepatica/metabolismo , Proteínas del Helminto/metabolismo , Macrófagos/fisiología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Animales , Catepsina B/genética , Catepsina B/metabolismo , Citocinas/genética , Citocinas/metabolismo , Fasciola hepatica/genética , Regulación de la Expresión Génica/fisiología , Proteínas del Helminto/genética , Concentración de Iones de Hidrógeno , Lisosomas/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Dióxido de Silicio/toxicidad
9.
BMC Immunol ; 18(1): 43, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28974200

RESUMEN

BACKGROUND: Macrophages are key players in the initiation, perpetuation and regulation of both innate and adaptive immune responses. They largely perform these roles through modulation of the expression of genes, especially those encoding cytokines. Murine bone marrow derived macrophages (BMDMs) are commonly used as a model macrophage population for the study of immune responses to pro-inflammatory stimuli, notably lipopolysaccharide (LPS), which may be pertinent to the human situation. Evaluation of the temporal responses of LPS stimulated macrophages is widely conducted via the measurement of gene expression levels by RT-qPCR. While providing a robust and sensitive measure of gene expression levels, RT-qPCR relies on the normalisation of gene expression data to a stably expressed reference gene. Generally, a normalisation gene(s) is selected from a list of "traditional" reference genes without validation of expression stability under the specific experimental conditions of the study. In the absence of such validation, and given that many studies use only a single reference gene, the reliability of data is questionable. RESULTS: The stability of expression levels of eight commonly used reference genes was assessed during the peak (6 h) and resolution (24 h) phases of the BMDM response to LPS. Further, this study identified two additional genes, which have not previously been described as reference genes, and the stability of their expression levels during the same phases of the inflammatory response were validated. Importantly, this study demonstrates that certain "traditional" reference genes are in fact regulated by LPS exposure, and, therefore, are not reliable candidates as their inclusion may compromise the accuracy of data interpretation. Testament to this, this study shows that the normalisation of gene expression data using an unstable reference gene greatly affects the experimental data obtained, and, therefore, the ultimate biological conclusions drawn. CONCLUSION: This study reaffirms the importance of validating reference gene stability for individual experimental conditions. Given that gene expression levels in LPS stimulated macrophages is routinely used to infer biological phenomena that are of relevance to human conditions, verification of reference gene expression stability is crucial.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Inflamación/genética , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Adyuvantes Inmunológicos/farmacología , Animales , Células Cultivadas , Expresión Génica/genética , Expresión Génica/inmunología , Perfilación de la Expresión Génica , Genes Esenciales/genética , Genes Esenciales/inmunología , Inflamación/inducido químicamente , Activación de Macrófagos/efectos de los fármacos , Ratones , Análisis por Micromatrices , Reproducibilidad de los Resultados , Factores de Tiempo
10.
Int J Mol Sci ; 17(4): 534, 2016 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-27070593

RESUMEN

Due to the limitations of current treatment regimes, gene therapy is a promising strategy being explored to correct blood glucose concentrations in diabetic patients. In the current study, we used a retroviral vector to deliver either the human insulin gene alone, the rat NeuroD1 gene alone, or the human insulin gene and rat NeuroD1 genes together, to the rat liver cell line, H4IIE, to determine if storage of insulin and pancreatic transdifferentiation occurred. Stable clones were selected and expanded into cell lines: H4IIEins (insulin gene alone), H4IIE/ND (NeuroD1 gene alone), and H4IIEins/ND (insulin and NeuroD1 genes). The H4IIEins cells did not store insulin; however, H4IIE/ND and H4IIEins/ND cells stored 65.5 ± 5.6 and 1475.4 ± 171.8 pmol/insulin/5 × 106 cells, respectively. Additionally, several ß cell transcription factors and pancreatic hormones were expressed in both H4IIE/ND and H4IIEins/ND cells. Electron microscopy revealed insulin storage vesicles in the H4IIE/ND and H4IIEins/ND cell lines. Regulated secretion of insulin to glucose (0-20 mmol/L) was seen in the H4IIEins/ND cell line. The H4IIEins/ND cells were transplanted into diabetic immunoincompetent mice, resulting in normalization of blood glucose. This data shows that the expression of NeuroD1 and insulin in liver cells may be a useful strategy for inducing islet neogenesis and reversing diabetes.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Ingeniería Celular/métodos , Transdiferenciación Celular , Glucosa/metabolismo , Insulina/genética , Insulina/metabolismo , Hígado/citología , Animales , Línea Celular , Diabetes Mellitus/genética , Diabetes Mellitus/terapia , Técnicas de Transferencia de Gen , Terapia Genética , Humanos , Hígado/metabolismo , Masculino , Ratones SCID , Ratas
11.
Br J Dev Psychol ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923552

RESUMEN

Do children consider temporal distance in their reasoning about the world? Using a novel method that relied minimally on verbal ability, we asked N = 106 3- to 6-year-olds to judge which of two characters felt more 'happy'/'sad' right now: one engaging in a pleasant/unpleasant activity tomorrow or another engaging in this same activity when they are a year older. That is, we examined whether children understood that the closer in time a future event, the more intense the currently felt emotion. Starting at age 4, children correctly judged which child was more 'happy'/'sad' right now. However, 4- to 6-year-olds tended not to explain their judgements by referring to temporal distance, per se. Results suggest that children are sensitive to temporal distance early in development, but do not yet verbally express this understanding. Implications for theories about children's future thinking and future areas of research are discussed.

12.
J Diabetes Res ; 2024: 8555211, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39022651

RESUMEN

We have previously identified a parasite-derived peptide, FhHDM-1, that prevented the progression of diabetes in nonobese diabetic (NOD) mice. Disease prevention was mediated by the activation of the PI3K/Akt pathway to promote ß-cell survival and metabolism without inducing proliferation. To determine the molecular mechanisms driving the antidiabetogenic effects of FhHDM-1, miRNA:mRNA interactions and in silico predictions of the gene networks were characterised in ß-cells, which were exposed to the proinflammatory cytokines that mediate ß-cell destruction in Type 1 diabetes (T1D), in the presence and absence of FhHDM-1. The predicted gene targets of miRNAs differentially regulated by FhHDM-1 mapped to the biological pathways that regulate ß-cell biology. Six miRNAs were identified as important nodes in the regulation of PI3K/Akt signaling. Additionally, IGF-2 was identified as a miRNA gene target that mediated the beneficial effects of FhHDM-1 on ß-cells. The findings provide a putative mechanism by which FhHDM-1 positively impacts ß-cells to permanently prevent diabetes. As ß-cell death/dysfunction underlies diabetes development, FhHDM-1 opens new therapeutic avenues.


Asunto(s)
Apoptosis , Citocinas , Células Secretoras de Insulina , MicroARNs , Transducción de Señal , MicroARNs/metabolismo , MicroARNs/genética , Animales , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Apoptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Citocinas/metabolismo , Ratones , Ratones Endogámicos NOD , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos
13.
J Gene Med ; 15(1): 28-41, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23293075

RESUMEN

BACKGROUND: Type 1 diabetes (T1D) results from an autoimmune attack against the insulin-producing ß-cells of the pancreas. The present study aimed to reverse T1D by gene therapy. METHODS: We used a novel surgical technique, which involves isolating the liver from the circulation before the delivery of a lentiviral vector carrying furin-cleavable human insulin (INS-FUR) or empty vector to the livers of diabetic non-obese diabetic mice (NOD). This was compared with the direct injection of the vector into the portal circulation. Mice were monitored for body weight and blood glucose. Intravenous glucose tolerance tests were performed. Expression of insulin and pancreatic transcription factors was determined by the reverse transcriptase-polymerase chain reaction and immunohistochemistry and immunoelectron microscopy was used to localise insulin. RESULTS: Using the novel surgical technique, we achieved long-term transduction (42% efficiency) of hepatocytes, restored normoglycaemia for 150 days (experimental endpoint) and re-established normal glucose tolerance. We showed the expression of ß-cell transcription factors, murine insulin, glucagon and somatostatin, and hepatic storage of insulin in granules. The expression of hepatic markers, C/EBP-ß, G6PC, AAT and GLUI was down-regulated in INS-FUR-treated livers. Liver function tests remained normal, with no evidence of intrahepatic inflammation or autoimmune destruction of the insulin-secreting liver tissue. By comparison, direct injection of INS-FUR reduced blood glucose levels, and no pancreatic transdifferentiation or normal glucose tolerance was observed. CONCLUSIONS: This gene therapy protocol has, for the first time, permanently reversed T1D with normal glucose tolerance in NOD mice and, as such, represents a novel therapeutic strategy for the treatment of T1D.


Asunto(s)
Diabetes Mellitus Tipo 1/terapia , Terapia Genética/métodos , Hígado/metabolismo , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Glucemia/análisis , Transdiferenciación Celular/efectos de los fármacos , Femenino , Furina/metabolismo , Vectores Genéticos , Glucagón/genética , Glucagón/metabolismo , Prueba de Tolerancia a la Glucosa , Hepatocitos/metabolismo , Proteína Homeobox Nkx-2.2 , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Insulina/biosíntesis , Insulina/sangre , Células Secretoras de Insulina/metabolismo , Lentivirus/genética , Ratones , Ratones Endogámicos NOD , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Factores de Transcripción Paired Box/genética , Factores de Transcripción Paired Box/metabolismo , Somatostatina/genética , Somatostatina/metabolismo , Transactivadores/genética , Transactivadores/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transducción Genética , Proteínas de Pez Cebra
14.
FASEB J ; 26(11): 4614-27, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22872675

RESUMEN

We previously reported the identification of a novel family of immunomodulatory proteins, termed helminth defense molecules (HDMs), that are secreted by medically important trematode parasites. Since HDMs share biochemical, structural, and functional characteristics with mammalian cathelicidin-like host defense peptides (HDPs), we proposed that HDMs modulate the immune response via molecular mimicry of host molecules. In the present study, we report the mechanism by which HDMs influence the function of macrophages. We show that the HDM secreted by Fasciola hepatica (FhHDM-1) binds to macrophage plasma membrane lipid rafts via selective interaction with phospholipids and/or cholesterol before being internalized by endocytosis. Following internalization, FhHDM-1 is rapidly processed by lysosomal cathepsin L to release a short C-terminal peptide (containing a conserved amphipathic helix that is a key to HDM function), which then prevents the acidification of the endolysosomal compartments by inhibiting vacuolar ATPase activity. The resulting endolysosomal alkalization impedes macrophage antigen processing and prevents the transport of peptides to the cell surface in conjunction with MHC class II for presentation to CD4(+) T cells. Thus, we have elucidated a novel mechanism by which helminth pathogens alter innate immune cell function to assist their survival in the host.


Asunto(s)
Adenosina Trifosfatasas/antagonistas & inhibidores , Adenosina Trifosfatasas/clasificación , Antígenos Helmínticos/metabolismo , Fasciola hepatica/metabolismo , Proteínas del Helminto/metabolismo , Macrófagos/metabolismo , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Secuencia de Aminoácidos , Animales , Catepsina L/genética , Catepsina L/metabolismo , Fasciola hepatica/inmunología , Regulación de la Expresión Génica/fisiología , Genes MHC Clase II , Proteínas del Helminto/genética , Humanos , Macrófagos/inmunología , Microdominios de Membrana/metabolismo , Datos de Secuencia Molecular , Unión Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
15.
Front Endocrinol (Lausanne) ; 14: 1205219, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37564976

RESUMEN

Diabetes is the fastest growing chronic disease globally, with prevalence increasing at a faster rate than heart disease and cancer. While the disease presents clinically as chronic hyperglycaemia, two distinct subtypes have been recognised. Type 1 diabetes (T1D) is characterised as an autoimmune disease in which the insulin-producing pancreatic ß-cells are destroyed, and type 2 diabetes (T2D) arises due to metabolic insufficiency, in which inadequate amounts of insulin are produced, and/or the actions of insulin are diminished. It is now apparent that pro-inflammatory responses cause a loss of functional ß-cell mass, and this is the common underlying mechanism of both T1D and T2D. Macrophages are the central immune cells in the pathogenesis of both diseases and play a major role in the initiation and perpetuation of the proinflammatory responses that compromise ß-cell function. Furthermore, it is the crosstalk between macrophages and ß-cells that orchestrates the inflammatory response and ensuing ß-cell dysfunction/destruction. Conversely, this crosstalk can induce immune tolerance and preservation of ß-cell mass and function. Thus, specifically targeting the intercellular communication between macrophages and ß-cells offers a unique strategy to prevent/halt the islet inflammatory events underpinning T1D and T2D. Due to their potent ability to regulate mammalian immune responses, parasitic worms (helminths), and their excretory/secretory products, have been examined for their potential as therapeutic agents for both T1D and T2D. This research has yielded positive results in disease prevention, both clinically and in animal models. However, the focus of research has been on the modulation of immune cells and their effectors. This approach has ignored the direct effects of helminths and their products on ß-cells, and the modulation of signal exchange between macrophages and ß-cells. This review explores how the alterations to macrophages induced by helminths, and their products, influence the crosstalk with ß-cells to promote their function and survival. In addition, the evidence that parasite-derived products interact directly with endocrine cells to influence their communication with macrophages to prevent ß-cell death and enhance function is discussed. This new paradigm of two-way metabolic conversations between endocrine cells and macrophages opens new avenues for the treatment of immune-mediated metabolic disease.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Helmintos , Animales , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/prevención & control , Diabetes Mellitus Tipo 2/metabolismo , Macrófagos/metabolismo , Insulina/metabolismo , Mamíferos
16.
Front Immunol ; 14: 1018076, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36761766

RESUMEN

We have previously identified an immune modulating peptide, termed FhHDM-1, within the secretions of the liver fluke, Fasciola hepatica, which is sufficiently potent to prevent the progression of type 1 diabetes and multiple sclerosis in murine models of disease. Here, we have determined that the FhHDM-1 peptide regulates inflammation by reprogramming macrophage metabolism. Specifically, FhHDM-1 switched macrophage metabolism to a dependence on oxidative phosphorylation fuelled by fatty acids and supported by the induction of glutaminolysis. The catabolism of glutamine also resulted in an accumulation of alpha ketoglutarate (α-KG). These changes in metabolic activity were associated with a concomitant reduction in glycolytic flux, and the subsequent decrease in TNF and IL-6 production at the protein level. Interestingly, FhHDM-1 treated macrophages did not express the characteristic genes of an M2 phenotype, thereby indicating the specific regulation of inflammation, as opposed to the induction of an anti-inflammatory phenotype per se. Use of an inactive derivative of FhHDM-1, which did not modulate macrophage responses, revealed that the regulation of immune responses was dependent on the ability of FhHDM-1 to modulate lysosomal pH. These results identify a novel functional association between the lysosome and mitochondrial metabolism in macrophages, and further highlight the significant therapeutic potential of FhHDM-1 to prevent inflammation.


Asunto(s)
Fasciola hepatica , Proteínas del Helminto , Animales , Ratones , Macrófagos , Péptidos/metabolismo , Inflamación
17.
J Diabetes ; 14(4): 247-260, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35191175

RESUMEN

Type 1 diabetes (T1D) is an autoimmune disease caused by the destruction of the insulin-producing ß-cells within the pancreas. Islet transplantation represents one cure; however, during islet preparation and post transplantation significant amounts of ß-cell death occur. Therefore, prevention and cure of T1D is dependent upon the preservation of ß-cell function and the prevention of ß-cell death. Phosphoinositide 3-kinase (PI3K)/Akt signaling represents a promising therapeutic target for T1D due to its pronounced effects on cellular survival, proliferation, and metabolism. A growing amount of evidence indicates that PI3K/Akt signaling is a critical determinant of ß-cell mass and function. Modulation of the PI3K/Akt pathway, directly (via the use of highly specific protein and peptide-based biologics, excretory/secretory products of parasitic worms, and complex constituents of plant extracts) or indirectly (through microRNA interactions) can regulate the ß-cell processes to ultimately determine the fate of ß-cell mass. An important consideration is the identification of the specific PI3K/Akt pathway modulators that enhance ß-cell function and prevent ß-cell death without inducing excessive ß-cell proliferation, which may carry carcinogenic side effects. Among potential PI3K/Akt pathway agonists, we have identified a novel parasite-derived protein, termed FhHDM-1 (Fasciola hepatica helminth defense molecule 1), which efficiently stimulates the PI3K/Akt pathway in ß-cells to enhance function and prevent death without concomitantly inducing proliferation unlike several other identified stimulators of PI3K/Akt signaling . As such, FhHDM-1 will inform the design of biologics aimed at targeting the PI3K/Akt pathway to prevent/ameliorate not only T1D but also T2D, which is now widely recognized as an inflammatory disease characterized by ß-cell dysfunction and death. This review will explore the modulation of the PI3K/Akt signaling pathway as a novel strategy to enhance ß-cell function and survival.


Asunto(s)
Productos Biológicos , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 1/terapia , Humanos , Fosfatidilinositol 3-Quinasa/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
18.
J Behav Ther Exp Psychiatry ; 74: 101694, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34543804

RESUMEN

BACKGROUND AND OBJECTIVES: This study replicates and extends Houle-Johnson et al.'s (2019) findings to better understand the role of feedback modality, ambiguity and social anxiety in the recognition and recall of self-relevant feedback. METHODS: Participants gave a speech and were provided with positive, negative, and ambiguous feedback via written text, (n = 33) or recorded sentences (n = 31) and later completed a recognition and recall task for the feedback. RESULTS: Recognition (p = .80, ηp2 = 0) and recall (p = .09, ηp2 = 0.08) did not differ between written or recorded feedback. All participants demonstrated a negative response bias (p < .001, ηp2 = 0.22) and recalled more negative than positive feedback (p = .02, ηp2 = 0.10) but were no more accurate in recognizing negative compared to positive feedback (p = .08, ηp2 = 0). Although social anxiety did not impact recognition accuracy (p = .94, ηp2 = 0), participants with high social anxiety demonstrated a more pronounced negative response bias (p < .01, ηp2 = 0.11) and negative recall bias (p = .02, SE = 1.12) than low social anxiety participants. Moreover, the more negatively ambiguous items were perceived, the more likely they were identified old in the high social anxiety group, whereas the opposite was true for the low social anxiety group (B = .13, p < .10). LIMITATIONS: Task believability was relatively low across all participants. CONCLUSIONS: Our findings suggest that modality does not influence memory for feedback. Moreover, social anxiety might be characterized by a negative bias in recall and response bias, but not necessarily increased accuracy in recognition of negative feedback.


Asunto(s)
Recuerdo Mental , Habla , Ansiedad , Retroalimentación , Humanos , Reconocimiento en Psicología
19.
Cells ; 11(14)2022 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-35883588

RESUMEN

Type 1 diabetes is a chronic illness in which the native beta (ß)-cell population responsible for insulin release has been the subject of autoimmune destruction. This condition requires patients to frequently measure their blood glucose concentration and administer multiple daily exogenous insulin injections accordingly. Current treatments fail to effectively treat the disease without significant side effects, and this has led to the exploration of different approaches for its treatment. Gene therapy and the use of viral vectors has been explored extensively and has been successful in treating a range of diseases. The use of viral vectors to deliver ß-cell transcription factors has been researched in the context of type 1 diabetes to induce the pancreatic transdifferentiation of cells to replace the ß-cell population destroyed in patients. Studies have used various combinations of pancreatic and ß-cell transcription factors in order to induce pancreatic transdifferentiation and have achieved varying levels of success. This review will outline why pancreatic transcription factors have been utilised and how their application can allow the development of insulin-producing cells from non ß-cells and potentially act as a cure for type 1 diabetes.


Asunto(s)
Transdiferenciación Celular , Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Transdiferenciación Celular/genética , Técnicas de Reprogramación Celular/métodos , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/terapia , Humanos , Insulina , Factores de Transcripción/genética
20.
Dev Psychol ; 57(3): 376-385, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33539121

RESUMEN

Future-oriented thought is ubiquitous in humans but challenging to study in children. Adults not only think about the future but can also represent a future state of the world that differs from the present. However, behavioral tasks to assess the development of future thought have not traditionally required children to do so as most can be solved based solely on representations of the present. To overcome this limitation, we modified an existing task such that children could not simply rely on a representation of the present to succeed (i.e., the correct answer for "right now" was different than the correct answer for "tomorrow"). A sample of 117 4- to 7-year-olds (64 girls and 53 boys) from Ottawa, Canada, and surrounding area, who were predominantly European Canadian (78.6% of sample) and had a family income of over $100,000 CAN (66.1% of sample) participated. Children remembered the information required to solve our task, and there were age-related changes in performance, but only 7-year-olds made an adaptive future-oriented decision significantly more often than chance. With the task modification removed (so the correct answer for the present and the future was the same), even 4-year-olds were above chance. Our work challenges the notion that starting at age 4, children solve behavioral tasks of future thinking by acting on their representations of the future. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Desarrollo Infantil , Pensamiento , Canadá , Niño , Preescolar , Femenino , Predicción , Humanos , Masculino , Tiempo
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