RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent chronic liver condition worldwide, demanding further investigation into its pathogenesis. Circular RNAs (circRNAs) are emerging as pivotal regulators in MASLD processes, yet their pathological implications in MASLD remain poorly understood. This study focused on elucidating the role of circular RNA ribonucleotide reductase subunit M2 (circRRM2) in MASLD progression. In this study, we used both in vitro and in vivo MASLD models using long-chain-free fatty acid (FFA)-treated hepatocytes and high-fat diet (HFD)-induced MASLD in mice, respectively. We determined the expression patterns of circRRM2, microRNA-142-5p (miR-142-5p), and neuregulin 1 (NRG1) in livers of MASLD-afflicted mice and MASLD hepatocytes by RT-qPCR. Dual-luciferase reporter assays verified the binding relationships among circRRM2, miR-142-5p, and NRG1. We conducted further analyses of their roles in MASLD hepatocytes and modulated circRRM2, miR-142-5p, and NRG1 expression in vitro by transfection. Our findings were validated in vivo. The results demonstrated reduced levels of circRRM2 and NRG1, along with elevated miR-142-5p expression in MASLD livers and hepatocytes. Overexpression of circRRM2 downregulated lipogenesis-related genes and decreased triglycerides accumulation in livers of MASLD mice. MiR-142-5p, which interacts with circRRM2, effectively counteracted the effects of circRRM2 in MASLD hepatocytes. Furthermore, NRG1 was identified as a miR-142-5p target, and its overexpression mitigated the regulatory impact of miR-142-5p on MASLD hepatocytes. In conclusion, circRRM2, via its role as a miR-142-5p sponge, upregulating NRG1, possibly influenced triglycerides accumulation in both in vitro and in vivo MASLD models.NEW & NOTEWORTHY CircRRM2 expression was downregulated in free fatty acid (FFA)-challenged hepatocytes and high-fat diet (HFD) fed mice. Overexpressed circular RNA ribonucleotide reductase subunit M2 (circRRM2) attenuated metabolic dysfunction-associated steatotic liver disease (MASLD) development by suppressing FFA-induced triglycerides accumulation. CircRRM2 targeted microRNA-142-5p (miR-142-5p), which served as an upstream inhibitor of neuregulin 1 (NRG1) and collaboratively regulated MASLD progression.

Asunto(s)

Dieta Alta en Grasa , Hepatocitos , MicroARNs , Neurregulina-1 , ARN Circular , Animales , MicroARNs/metabolismo , MicroARNs/genética , Ratones , Hepatocitos/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Masculino , Neurregulina-1/genética , Neurregulina-1/metabolismo , Ratones Endogámicos C57BL , Hígado Graso/metabolismo , Hígado Graso/genética , Humanos , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ribonucleósido Difosfato Reductasa

RESUMEN

The growth factor Neuregulin-1 (NRG1) has pleiotropic roles in proliferation and differentiation of the stem cell niche in different tissues. It has been implicated in gut, brain and muscle development and repair. Six isoform classes of NRG1 and over 28 protein isoforms have been previously described. Here we report a new class of NRG1, designated NRG1-VII to denote that these NRG1 isoforms arise from a myeloid-specific transcriptional start site (TSS) previously uncharacterized. Long-read sequencing was used to identify eight high-confidence NRG1-VII transcripts. These transcripts presented major structural differences from one another, through the use of cassette exons and alternative stop codons. Expression of NRG1-VII was confirmed in primary human monocytes and tissue resident macrophages and induced pluripotent stem cell-derived macrophages (iPSC-derived macrophages). Isoform switching via cassette exon usage and alternate polyadenylation was apparent during monocyte maturation and macrophage differentiation. NRG1-VII is the major class expressed by the myeloid lineage, including tissue-resident macrophages. Analysis of public gene expression data indicates that monocytes and macrophages are a primary source of NRG1. The size and structure of class VII isoforms suggests that they may be more diffusible through tissues than other NRG1 classes. However, the specific roles of class VII variants in tissue homeostasis and repair have not yet been determined.

Asunto(s)

Diferenciación Celular , Macrófagos , Neurregulina-1 , Isoformas de Proteínas , Humanos , Neurregulina-1/metabolismo , Neurregulina-1/genética , Macrófagos/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Monocitos/metabolismo , Monocitos/citología , Sitio de Iniciación de la Transcripción , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/citología , Exones/genética , Empalme Alternativo , Células Mieloides/metabolismo , Células Mieloides/citología

RESUMEN

The age-related alterations in pituitary function, including changes in prolactin (PRL) production contributes to the systemic susceptibility to age-related diseases. Our previous research has shown the involvement of Nrg1 in regulating the expression and secretion of PRL. However, the precise role of Nrg1 in mitigating the senescence of pituitary lactotrophs and the underlying mechanisms are yet to be comprehended. Here, data from the GEPIA database was used to evaluate the association between transient receptor potential cation channel subfamily M member 8 (TRPM8) and PRL in normal human pituitary tissues, followed by immunofluorescence verification using a human pituitary tissue microarray. TRPM8 levels showed a significant positive association with PRL expression in normal human pituitary tissues, and both TRPM8 and PRL levels declined during aging, suggesting that TRPM8 may regulate pituitary aging by affecting PRL production. It was also found that treatment with exogenous neuregulin 1 (Nrg1) markedly delayed the senescence of GH3 cells (rat lactotroph cell line) generated by D-galactose (D-gal). In addition, melatonin reduced the levels of senescence-related markers in senescent pituitary cells by promoting Nrg1 / ErbB4 signaling, stimulating PRL expression and secretion. Further investigation showed that Nrg1 attenuated senescence in pituitary cells by increasing TRPM8 expression. Downregulation of TRPM8 activation eliminated Nrg1-mediated amelioration of pituitary cell senescence. These findings demonstrate the critical function of Nrg1 / ErbB signaling in delaying pituitary lactotroph cell senescence and enhancing PRL production via promoting TRPM8 expression under the modulation of melatonin.

Asunto(s)

Senescencia Celular , Lactotrofos , Melatonina , Neurregulina-1 , Prolactina , Transducción de Señal , Canales Catiónicos TRPM , Prolactina/metabolismo , Canales Catiónicos TRPM/metabolismo , Canales Catiónicos TRPM/genética , Humanos , Senescencia Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Lactotrofos/metabolismo , Lactotrofos/efectos de los fármacos , Melatonina/farmacología , Animales , Ratas , Neurregulina-1/metabolismo , Neurregulina-1/genética , Hipófisis/metabolismo , Hipófisis/efectos de los fármacos , Envejecimiento/metabolismo , Receptor ErbB-4/metabolismo , Receptor ErbB-4/genética , Línea Celular , Masculino , Femenino

RESUMEN

Cancer is rarely the straightforward consequence of an abnormality in a single gene, but rather reflects a complex interplay of many genes, represented as gene modules. Here, we leverage the recent advances of model-agnostic interpretation approach and develop CGMega, an explainable and graph attention-based deep learning framework to perform cancer gene module dissection. CGMega outperforms current approaches in cancer gene prediction, and it provides a promising approach to integrate multi-omics information. We apply CGMega to breast cancer cell line and acute myeloid leukemia (AML) patients, and we uncover the high-order gene module formed by ErbB family and tumor factors NRG1, PPM1A and DLG2. We identify 396 candidate AML genes, and observe the enrichment of either known AML genes or candidate AML genes in a single gene module. We also identify patient-specific AML genes and associated gene modules. Together, these results indicate that CGMega can be used to dissect cancer gene modules, and provide high-order mechanistic insights into cancer development and heterogeneity.

Asunto(s)

Neoplasias de la Mama , Aprendizaje Profundo , Redes Reguladoras de Genes , Leucemia Mieloide Aguda , Redes Neurales de la Computación , Humanos , Leucemia Mieloide Aguda/genética , Neoplasias de la Mama/genética , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Neurregulina-1/genética , Neurregulina-1/metabolismo

RESUMEN

Gut microbiota is responsible for essential functions in human health. Several communication axes between gut microbiota and other organs via neural, endocrine, and immune pathways have been described, and perturbation of gut microbiota composition has been implicated in the onset and progression of an emerging number of diseases. Here, we analyzed peripheral nerves, dorsal root ganglia (DRG), and skeletal muscles of neonatal and young adult mice with the following gut microbiota status: a) germ-free (GF), b) gnotobiotic, selectively colonized with 12 specific gut bacterial strains (Oligo-Mouse-Microbiota, OMM12), or c) natural complex gut microbiota (CGM). Stereological and morphometric analyses revealed that the absence of gut microbiota impairs the development of somatic median nerves, resulting in smaller diameter and hypermyelinated axons, as well as in smaller unmyelinated fibers. Accordingly, DRG and sciatic nerve transcriptomic analyses highlighted a panel of differentially expressed developmental and myelination genes. Interestingly, the type III isoform of Neuregulin1 (NRG1), known to be a neuronal signal essential for Schwann cell myelination, was overexpressed in young adult GF mice, with consequent overexpression of the transcription factor Early Growth Response 2 (Egr2), a fundamental gene expressed by Schwann cells at the onset of myelination. Finally, GF status resulted in histologically atrophic skeletal muscles, impaired formation of neuromuscular junctions, and deregulated expression of related genes. In conclusion, we demonstrate for the first time a gut microbiota regulatory impact on proper development of the somatic peripheral nervous system and its functional connection to skeletal muscles, thus suggesting the existence of a novel 'Gut Microbiota-Peripheral Nervous System-axis.'

Asunto(s)

Ganglios Espinales , Microbioma Gastrointestinal , Unión Neuromuscular , Animales , Unión Neuromuscular/microbiología , Ratones , Ganglios Espinales/metabolismo , Ganglios Espinales/microbiología , Vida Libre de Gérmenes , Nervios Periféricos/microbiología , Nervios Periféricos/crecimiento & desarrollo , Músculo Esquelético/microbiología , Ratones Endogámicos C57BL , Neurregulina-1/metabolismo , Neurregulina-1/genética , Masculino , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Células de Schwann/microbiología , Células de Schwann/metabolismo

RESUMEN

Schizophrenia is associated with altered cortical circuitry. Although the schizophrenia risk gene NRG1 is known to affect the wiring of inhibitory interneurons, its role in excitatory neurons and axonal development is unclear. Here, we investigated the role of Nrg1 in the development of the corpus callosum, the major interhemispheric connection formed by cortical excitatory neurons. We found that deletion of Nrg1 impaired callosal axon development in vivo. Experiments in vitro and in vivo demonstrated that Nrg1 is cell-autonomously required for axonal outgrowth and that intracellular signaling of Nrg1 is sufficient to promote axonal development in cortical neurons and specifically in callosal axons. Furthermore, our data suggest that Nrg1 signaling regulates the expression of Growth Associated Protein 43, a key regulator of axonal growth. In conclusion, our study demonstrates that NRG1 is involved in the formation of interhemispheric callosal connections and provides a novel perspective on the relevance of NRG1 in excitatory neurons and in the etiology of schizophrenia.

Asunto(s)

Axones , Cuerpo Calloso , Neurregulina-1 , Transducción de Señal , Animales , Neurregulina-1/metabolismo , Neurregulina-1/genética , Cuerpo Calloso/metabolismo , Axones/metabolismo , Ratones , Esquizofrenia/metabolismo , Esquizofrenia/genética , Esquizofrenia/etiología , Esquizofrenia/patología , Ratones Noqueados , Neuronas/metabolismo , Proteína GAP-43/metabolismo , Proteína GAP-43/genética , Ratones Endogámicos C57BL

RESUMEN

Candida albicans is a polymorphic human fungal pathogen and the prime etiological agent responsible for candidiasis. The main two aspects of C. albicans virulence that have been suggested are yeast-to-hyphal (Y-H) morphological transitions and biofilm development. Anti-fungal agents targeting these virulence attributes enhances the antifungal drug development process. Repositioning with other non-fungal drugs offered a one of the new strategies and a potential alternative option to counter the urgent need for antifungal drug development. In the current study, an antiviral drug ganciclovir was screened as an antifungal agent against ATCC 90028, 10231 and clinical isolate (C1). Ganciclovir at 0.5 mg/ml concentration reduced 50% hyphal development on a silicon-based urinary catheter and was visualized using scanning electron microscopy. Ganciclovir reduced ergosterol biosynthesis in both strains and C1 isolate of C. albicans in a concentration-dependent manner. Additionally, a gene expression profile study showed that ganciclovir treatment resulted in upregulation of hyphal-specific repressors MIG1, TUP1, and NRG1 in C. albicans. Additionally, an in vivo study on the Bombyx mori silkworm model further evidenced the virulence inhibitory ability of ganciclovir (0.5 mg/ml) against C. albicans. This is the first report that explore the novel anti-morphogenic activities of ganciclovir against the pathogenic C. albicans strains, along with clinical isolates. Further, ganciclovir may be considered for therapeutic purpose after combinations with standard antifungal agents.

Asunto(s)

Antifúngicos , Candida albicans , Proteínas Fúngicas , Ganciclovir , Hifa , Candida albicans/efectos de los fármacos , Candida albicans/genética , Candida albicans/crecimiento & desarrollo , Hifa/efectos de los fármacos , Hifa/crecimiento & desarrollo , Antifúngicos/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Ganciclovir/farmacología , Animales , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Candidiasis/microbiología , Candidiasis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Neurregulina-1/genética , Neurregulina-1/metabolismo , Virulencia/efectos de los fármacos , Humanos , Morfogénesis/efectos de los fármacos , Proteínas Represoras/genética , Proteínas Represoras/metabolismo

RESUMEN

In addition to controlling smooth muscle tone in coronary vessels, endothelial cells also influence subjacent cardiomyocyte growth. Because heparanase, with exclusive expression in endothelial cells, enables extracellular matrix remodeling, angiogenesis, metabolic reprogramming, and cell survival, it is conceivable that it could also encourage development of cardiac hypertrophy. Global heparanase overexpression resulted in physiologic cardiac hypertrophy, likely an outcome of HSPG clustering and activation of hypertrophic signaling. The heparanase autocrine effect of releasing neuregulin-1 could have also contributed to this overexpression. Hyperglycemia induced by streptozotocin-induced diabetes sensitized the heart to flow-induced release of heparanase and neuregulin-1. Despite this excess secretion, progression of diabetes caused significant gene expression changes related to mitochondrial metabolism and cell death that led to development of pathologic hypertrophy and heart dysfunction. Physiologic cardiac hypertrophy was also observed in rats with cardiomyocyte-specific vascular endothelial growth factor B overexpression. When perfused, hearts from these animals released significantly higher amounts of both heparanase and neuregulin-1. However, subjecting these animals to diabetes triggered robust transcriptome changes related to metabolism and a transition to pathologic hypertrophy. Our data suggest that in the absence of mechanisms that support cardiac energy generation and prevention of cell death, as seen after diabetes, there is a transition from physiologic to pathologic cardiac hypertrophy and a decline in cardiac function.

Asunto(s)

Cardiomegalia , Diabetes Mellitus Experimental , Glucuronidasa , Remodelación Ventricular , Animales , Masculino , Ratas , Cardiomegalia/metabolismo , Cardiomegalia/patología , Diabetes Mellitus Experimental/metabolismo , Glucuronidasa/metabolismo , Glucuronidasa/genética , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Neurregulina-1/metabolismo , Neurregulina-1/genética , Remodelación Ventricular/fisiología , Femenino

RESUMEN

Neuregulin-1 (Nrg1, gene symbol: Nrg1), a ligand of the ErbB receptor family, promotes intestinal epithelial cell proliferation and repair. However, the dynamics and accurate derivation of Nrg1 expression during colitis remain unclear. By analyzing the public single-cell RNA-sequencing datasets and employing a dextran sulfate sodium (DSS)-induced colitis model, we investigated the cell source of Nrg1 expression and its potential regulator in the process of epithelial healing. Nrg1 was majorly expressed in stem-like fibroblasts arising early in mouse colon after DSS administration, and Nrg1-Erbb3 signaling was identified as a potential mediator of interaction between stem-like fibroblasts and colonic epithelial cells. During the ongoing colitis phase, a significant infiltration of macrophages and neutrophils secreting IL-1ß emerged, accompanied by the rise in stem-like fibroblasts that co-expressed Nrg1 and IL-1 receptor 1. By stimulating intestinal or lung fibroblasts with IL-1ß in the context of inflammation, we observed a downregulation of Nrg1 expression. Patients with inflammatory bowel disease also exhibited an increase in NRG1+IL1R1+ fibroblasts and an interaction of NRG1-ERBB between IL1R1+ fibroblasts and colonic epithelial cells. This study reveals a novel potential mechanism for mucosal healing after inflammation-induced epithelial injury, in which inflammatory myeloid cell-derived IL-1ß suppresses the early regeneration of intestinal tissue by interfering with the secretion of reparative neuregulin-1 by stem-like fibroblasts.

Asunto(s)

Colitis , Sulfato de Dextran , Fibroblastos , Mucosa Intestinal , Neurregulina-1 , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Colitis/metabolismo , Colitis/inducido químicamente , Colitis/patología , Sulfato de Dextran/efectos adversos , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Fibroblastos/metabolismo , Interleucina-1beta/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Ratones Endogámicos C57BL , Células Mieloides/metabolismo , Neurregulina-1/metabolismo , Neurregulina-1/genética , Receptor ErbB-3/metabolismo , Receptor ErbB-3/genética , Receptores Tipo I de Interleucina-1/metabolismo , Receptores Tipo I de Interleucina-1/genética

RESUMEN

Zebrafish have a lifelong cardiac regenerative ability after damage, whereas mammals lose this capacity during early postnatal development. This study investigated whether the declining expression of growth factors during postnatal mammalian development contributes to the decrease of cardiomyocyte regenerative potential. Besides confirming the proliferative ability of neuregulin 1 (NRG1), interleukin (IL)1b, receptor activator of nuclear factor kappa-Β ligand (RANKL), insulin growth factor (IGF)2, and IL6, we identified other potential pro-regenerative factors, with BMP7 exhibiting the most pronounced efficacy. Bmp7 knockdown in neonatal mouse cardiomyocytes and loss-of-function in adult zebrafish during cardiac regeneration reduced cardiomyocyte proliferation, indicating that Bmp7 is crucial in the regenerative stages of mouse and zebrafish hearts. Conversely, bmp7 overexpression in regenerating zebrafish or administration at post-mitotic juvenile and adult mouse stages, in vitro and in vivo following myocardial infarction, enhanced cardiomyocyte cycling. Mechanistically, BMP7 stimulated proliferation through BMPR1A/ACVR1 and ACVR2A/BMPR2 receptors and downstream SMAD5, ERK, and AKT signaling. Overall, BMP7 administration is a promising strategy for heart regeneration.

Asunto(s)

Proteína Morfogenética Ósea 7 , Proliferación Celular , Miocitos Cardíacos , Regeneración , Pez Cebra , Animales , Femenino , Masculino , Ratones , Proteína Morfogenética Ósea 7/metabolismo , Proteína Morfogenética Ósea 7/genética , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/metabolismo , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Ratones Endogámicos C57BL , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Miocitos Cardíacos/metabolismo , Neurregulina-1/metabolismo , Neurregulina-1/genética , Transducción de Señal , Proteína Smad5/metabolismo , Pez Cebra/metabolismo , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética

RESUMEN

Ovarian fibrosis contributes to age-related ovarian dysfunction. In our previous study, we observed ovarian fibrosis in both obese and aging mice with intracellular lipid droplets in the fibrotic ovaries. Although the importance of mitochondria in ovarian fibrosis has been recognized in pharmacological studies, their role in lipid metabolism remains unclear. Globin peptide (GP), derived from hemoglobin, enhances lipid metabolism in obese mice. This study aimed to elucidate the importance of lipid metabolism in ovarian fibrosis by using GP. Treatment of ovarian stromal cells with GP increased mitochondrial oxygen consumption during ß-oxidation. Lipid accumulation was also observed in the ovaries of granulosa cell-specific Nrg1 knockout mice (gcNrg1KO), and the administration of GP to gcNrg1KO mice for two months reduced ovarian lipid accumulation and fibrosis in addition to restoring the estrous cycle. GP holds promise for mitigating lipid-related ovarian issues and provides a novel approach to safeguarding ovarian health by regulating fibrosis via lipid pathways.

Asunto(s)

Envejecimiento , Fertilidad , Fibrosis , Globinas , Células de la Granulosa , Metabolismo de los Lípidos , Ratones Noqueados , Neurregulina-1 , Animales , Femenino , Ratones , Células de la Granulosa/efectos de los fármacos , Células de la Granulosa/metabolismo , Fertilidad/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Globinas/metabolismo , Globinas/genética , Neurregulina-1/metabolismo , Neurregulina-1/genética , Ovario/efectos de los fármacos , Ovario/metabolismo , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Ciclo Estral/efectos de los fármacos , Péptidos/farmacología

RESUMEN

Motivation-driven mating is a basic affair for the maintenance of species. However, the underlying molecular mechanisms that control mating motivation are not fully understood. Here, we report that NRG1-ErbB4 signaling in the medial amygdala (MeA) is pivotal in regulating mating motivation. NRG1 expression in the MeA negatively correlates with the mating motivation levels in adult male mice. Local injection and knockdown of MeA NRG1 reduce and promote mating motivation, respectively. Consistently, knockdown of MeA ErbB4, a major receptor for NRG1, and genetic inactivation of its kinase both promote mating motivation. ErbB4 deletion decreases neuronal excitability, whereas chemogenetic manipulations of ErbB4-positive neuronal activities bidirectionally modulate mating motivation. We also identify that the effects of NRG1-ErbB4 signaling on neuronal excitability and mating motivation rely on hyperpolarization-activated cyclic nucleotide-gated channel 3. This study reveals a critical molecular mechanism for regulating mating motivation in adult male mice.

Asunto(s)

Motivación , Transducción de Señal , Ratones , Masculino , Animales , Neuronas/metabolismo , Receptor ErbB-4/metabolismo , Amígdala del Cerebelo/metabolismo , Neurregulina-1/metabolismo

RESUMEN

Neuregulin 1 (NRG1) belonging to the transmembrane growth factors family is widespread in living organisms. It acts through ErbB family receptors and first of all takes part in embryogenesis, as well as in developmental, regenerative and adaptive processes occurring in various internal organs and systems. It is known that NRG1 and its receptors are present in various parts of the gastrointestinal (GI) tract. First of all NRG1 and ErbB receptors have been detected in the enteric nervous system (ENS) localized in the wall of the esophagus, stomach and intestine and regulating the majority of the GI tract functions, but also in the mucosal and muscular layers of the GI tract. The NRG1/ErbB pathway is involved in the development and differentiation of the ENS and regulation of the intestinal epithelium functions. Moreover, dysregulation of this pathway results in a wide range of gastrointestinal diseases. However, till now there are no summarizations of previous studies concerning distribution and functions of NRG1 and its receptors in the GI tract. The present review fills this gap.

Asunto(s)

Sistema Nervioso Entérico , Tracto Gastrointestinal , Neurregulina-1 , Neurregulina-1/metabolismo , Sistema Nervioso Entérico/metabolismo , Humanos , Animales , Tracto Gastrointestinal/inervación , Tracto Gastrointestinal/metabolismo , Receptores ErbB/metabolismo , Transducción de Señal

RESUMEN

Gene fusions and rearrangements play a crucial role in tumor biology. They are rare events typically detected in KRAS wild-type (WT) pancreatic tumors. Their identification can inform clinical management by enabling precision oncology, as fusions involving BRAF, FGFR2, RET, NTRK, NRG1, and ALK represent actionable targets in KRAS-WT cancers, and serve diagnostic purposes since fusions involving PRKACA/B represent the diagnostic hallmark of intraductal oncocytic papillary neoplasms (IOPNs). Although they are rare, the therapeutic and diagnostic importance of these genomic events should not be underestimated, highlighting the need for quality-ensured molecular diagnostics in the management of cancer. Herein we review the existing literature on the role of fusion genes in pancreatic tumors and their clinical potential as effective biomarkers and therapeutic targets.

Asunto(s)

Proteínas de Fusión Oncogénica , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Proteínas de Fusión Oncogénica/genética , Biomarcadores de Tumor/genética , Receptor trkA/genética , Proteínas Proto-Oncogénicas c-ret/genética , Proteínas Proto-Oncogénicas B-raf/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Neurregulina-1/genética , Neurregulina-1/metabolismo , Quinasa de Linfoma Anaplásico/genética , Fusión Génica

Asunto(s)

Neurregulina-1 , Transducción de Señal , Aislamiento Social , Animales , Aislamiento Social/psicología , Neurregulina-1/metabolismo , Neurregulina-1/genética , Trastorno Autístico/psicología , Trastorno Autístico/fisiopatología , Complejo Nuclear Corticomedial/metabolismo , Humanos , Adolescente , Ratones , Masculino , Amígdala del Cerebelo/metabolismo

RESUMEN

Candida albicans is one of the most common causes of superficial and invasive fungal diseases in humans. Its ability to cause disease is closely linked to its ability to undergo a morphological transition from budding yeast to filamentous forms (hyphae and pseudohyphae). The extent to which C. albicans strains isolated from patients undergo filamentation varies significantly. In addition, the filamentation phenotypes of mutants involving transcription factors that positively regulate hyphal morphogenesis can also vary from strain to strain. Here, we characterized the virulence, in vitro and in vivo filamentation, and in vitro and in vivo hypha-associated gene expression profiles for four poorly filamenting C. albicans isolates and their corresponding deletion mutants of the repressor of filamentation NRG1. The two most virulent strains, 57055 and 78048, show robust in vivo filamentation but are predominately yeast phase under in vitro hypha induction; the two low-virulence strains (94015 and 78042) do not undergo filamentation well under either condition. In vitro, deletion of NRG1 increases hyphae formation in the SC5314 derivative SN250, but only pseudohyphae are formed in the clinical isolates. Deletion of NRG1 modestly increased the virulence of 78042, which was accompanied by increased expression of hypha-associated genes without an increase in filamentation. Strikingly, deletion of NRG1 in 78048 reduced filamentation in vivo, expression of candidalysin (ECE1), and virulence without dramatically altering establishment of infection. Thus, the function of the conserved repressor NRG1 in C. albicans shows strain-based heterogeneity during infection.IMPORTANCEClinical isolates of the human fungal pathogen Candida albicans show significant variation in their ability to undergo in vitro filamentation and in the function of well-characterized transcriptional regulators of filamentation. Here, we show that Nrg1, a key repressor of filamentation and filament specific gene expression in standard reference strains, has strain-dependent functions, particularly during infection. Most strikingly, loss of NRG1 function can reduce filamentation, hypha-specific gene expression such as the toxin candidalysin, and virulence in some strains. Our data emphasize that the functions of seemingly fundamental and well-conserved transcriptional regulators such as Nrg1 are contextual with respect to both environment and genetic backgrounds.

Asunto(s)

Candida albicans , Candidiasis , Humanos , Candidiasis/microbiología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Virulencia , Neurregulina-1/genética , Neurregulina-1/metabolismo

RESUMEN

BACKGROUND: Facial nerve injury often results in poor prognosis due to the challenging process of nerve regeneration. Neuregulin-1, a human calmodulin, is under investigation in this study for its impact on the reparative capabilities of Dental Pulp Stem Cells (DPSCs) in facial nerve injury. METHODS: Lentivirus was used to transfect and construct Neuregulin-1 overexpressed DPSCs. Various techniques assessed the effects of Neuregulin-1: osteogenic induction, lipid induction, Reverse Transcription Polymerase Chain Reaction, Western Blot, Cell Counting Kit-8 assay, wound healing, immunofluorescence, Phalloidin staining, nerve stem action potential, Hematoxylin-eosin staining, transmission electron microscopy, and immunohistochemistry. RESULTS: Neuregulin-1 effectively enhanced the proliferation, migration, and cytoskeletal rearrangement of DPSCs, while simultaneously suppressing the expression of Ras homolog gene family member A (RhoA) and Microfilament actin (F-actin). These changes facilitated the neural differentiation of DPSCs. Additionally, in vivo experiments showed that Neuregulin-1 expedited the restoration of action potential in the facial nerve trunk, increased the thickness of the myelin sheath, and stimulated axon regeneration. CONCLUSION: Neuregulin-1 has the capability to facilitate the repair of facial nerve injuries by promoting the regenerative capacity of DPSCs. Thus, Neuregulin-1 is a significant potential gene in the reparative processes of nerve damage.

Asunto(s)

Pulpa Dental , Traumatismos del Nervio Facial , Humanos , Axones , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Traumatismos del Nervio Facial/metabolismo , Regeneración Nerviosa/fisiología , Neurregulina-1/metabolismo , Células Madre/metabolismo

RESUMEN

BACKGROUND: Neuregulin-1 (NRG1) is implicated in both cancer and neurologic diseases such as amyotrophic lateral sclerosis (ALS); however, to date, there has been little cross-field discussion between neurology and oncology in regard to these genes and their functions. MAIN BODY: Approximately 0.15-0.5% of cancers harbor NRG1 fusions that upregulate NRG1 activity and hence that of the cognate ERBB3/ERBB4 (HER3/HER4) receptors; abrogating this activity with small molecule inhibitors/antibodies shows preliminary tissue-agnostic anti-cancer activity. Notably, ERBB/HER pharmacologic suppression is devoid of neurologic toxicity. Even so, in ALS, attenuated ERBB4/HER4 receptor activity (due to loss-of-function germline mutations or other mechanisms in sporadic disease) is implicated; indeed, ERBB4/HER4 is designated ALS19. Further, secreted-type NRG1 isoforms may be upregulated (perhaps via a feedback loop) and could contribute to ALS pathogenesis through aberrant glial cell stimulation via enhanced activity of other (e.g., ERBB1-3/HER1-3) receptors and downstream pathways. Hence, pan-ERBB inhibitors, already in use for cancer, may be agents worthy of testing in ALS. CONCLUSION: Common signaling cascades between cancer and ALS may represent novel therapeutic targets for both diseases.

Asunto(s)

Esclerosis Amiotrófica Lateral , Neoplasias , Neurregulina-1 , Receptor ErbB-4 , Humanos , Esclerosis Amiotrófica Lateral/genética , Neoplasias/genética , Neurregulina-1/genética , Neurregulina-1/metabolismo , Receptor ErbB-4/genética , Receptor ErbB-4/metabolismo , Transducción de Señal

RESUMEN

BACKGROUND: Patients with Alzheimer's disease (AD) are often co-morbid with unprovoked seizures, making clinical diagnosis and management difficult. Although it has an important role in both AD and epilepsy, abnormal γ-aminobutyric acid (GABA)ergic transmission is recognized only as a compensative change for glutamatergic damage. Neuregulin 1 (NRG1)-ErbB4 signaling can promote GABA release and suppress epileptogenesis, but its effects on cognition in AD are still controversial. METHODS: Four-month-old APPswe/PS1dE9 mice (APP mice) were used as animal models in the early stage of AD in this study. Acute/chronic chemical-kindling epilepsy models were established with pentylenetetrazol. Electroencephalogram and Racine scores were performed to assess seizures. Behavioral tests were used to assess cognition and emotion. Electrophysiology, western blot and immunofluorescence were performed to detect the alterations in synapses, GABAergic system components and NRG1-ErbB4 signaling. Furthermore, NRG1 was administrated intracerebroventricularly into APP mice and then its antiepileptic and cognitive effects were evaluated. RESULTS: APP mice had increased susceptibility to epilepsy and resulting hippocampal synaptic damage and cognitive impairment. Electrophysiological analysis revealed decreased GABAergic transmission in the hippocampus. This abnormal GABAergic transmission involved a reduction in the number of parvalbumin interneurons (PV+ Ins) and decreased levels of GABA synthesis and transport. We also found impaired NRG1-ErbB4 signaling which mediated by PV+ Ins loss. And NRG1 administration could effectively reduce seizures and improve cognition in four-month-old APP mice. CONCLUSION: Our results indicated that abnormal GABAergic transmission mediated hippocampal hyperexcitability, further excitation/inhibition imbalance, and promoted epileptogenesis in the early stage of AD. Appropriate NRG1 administration could down-regulate seizure susceptibility and rescue cognitive function. Our study provided a potential direction for intervening in the co-morbidity of AD and epilepsy.

Asunto(s)

Enfermedad de Alzheimer , Epilepsia , Humanos , Ratones , Animales , Lactante , Receptor ErbB-4/metabolismo , Enfermedad de Alzheimer/complicaciones , Hipocampo/metabolismo , Ácido gamma-Aminobutírico , Convulsiones , Neurregulina-1/metabolismo

RESUMEN

INTRODUCTION: NRG1 gene fusions are clinically actionable alterations identified in NSCLC and other tumors. Previous studies have reported that NRG1 fusions signal through HER2 and HER3 but, thus far, strategies targeting HER3 specifically or HER2-HER3 signaling have exhibited modest activity in patients with NSCLC bearing NRG1 fusions. Although NRG1 fusion proteins can bind HER4 in addition to HER3, the contribution of HER4 and other HER family members in NRG1 fusion-positive cancers is not fully understood. METHODS: We investigated the role of HER4 and EGFR-HER3 signaling in NRG1 fusion-positive cancers using Ba/F3 models engineered to express various HER family members in combination with NRG1 fusions and in vitro and in vivo models of NRG1 fusion-positive cancer. RESULTS: We determined that NRG1 fusions can stimulate downstream signaling and tumor cell growth through HER4, independent of other HER family members. Moreover, EGFR-HER3 signaling is also activated in cells expressing NRG1 fusions, and inhibition of these receptors is also necessary to effectively inhibit tumor cell growth. We observed that cetuximab, an anti-EGFR antibody, in combination with anti-HER2 antibodies, trastuzumab and pertuzumab, yielded a synergistic effect. Furthermore, pan-HER tyrosine kinase inhibitors were more effective than tyrosine kinase inhibitors with greater specificity for EGFR, EGFR-HER2, or HER2-HER4, although the relative degree of dependence on EGFR or HER4 signaling varied between different NRG1 fusion-positive cancers. CONCLUSIONS: Our findings indicate that pan-HER inhibition including HER4 and EGFR blockade is more effective than selectively targeting HER3 or HER2-HER3 in NRG1 fusion-positive cancers.

Asunto(s)

Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neurregulina-1/genética , Neurregulina-1/metabolismo , Receptor ErbB-2 , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Transducción de Señal