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1.
Sci Rep ; 11(1): 16268, 2021 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-34381120

RESUMEN

Volume accommodation occurs via a novel mechanism involving interstitial cells in detrusor muscles. The interstitial cells in the bladder are PDGFRα+, and they restrain the excitability of smooth muscle at low levels and prevents the development of transient contractions (TCs). A common clinical manifestation of spinal cord injury (SCI)-induced bladder dysfunction is detrusor overactivity (DO). Although a myogenic origin of DO after SCI has been suggested, a mechanism for development of SCI-induced DO has not been determined. In this study we hypothesized that SCI-induced DO is related to loss of function in the regulatory mechanism provided by PDGFRα+ cells. Our results showed that transcriptional expression of Pdgfra and Kcnn3 was decreased after SCI. Proteins encoded by these genes also decreased after SCI, and a reduction in PDGFRα+ cell density was also documented. Loss of PDGFRα+ cells was due to apoptosis. TCs in ex vivo bladders during filling increased dramatically after SCI, and this was related to the loss of regulation provided by SK channels, as we observed decreased sensitivity to apamin. These findings show that damage to the mechanism restraining muscle contraction during bladder filling that is provided by PDGFRα+ cells is causative in the development of DO after SCI.


Asunto(s)
Contracción Muscular/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Traumatismos de la Médula Espinal/complicaciones , Vejiga Urinaria Hiperactiva/etiología , Vejiga Urinaria/metabolismo , Vejiga Urinaria/fisiopatología , Animales , Apamina/metabolismo , Apoptosis , Expresión Génica , Ratones , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/genética , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/metabolismo , Traumatismos de la Médula Espinal/genética , Vejiga Urinaria/citología , Vejiga Urinaria/patología , Vejiga Urinaria Hiperactiva/fisiopatología
2.
JCI Insight ; 5(21)2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-33001865

RESUMEN

Chronic kidney disease (CKD) induces the failure of arteriovenous fistulas (AVFs) and promotes the differentiation of vascular adventitial GLI1-positive mesenchymal stem cells (GMCs). However, the roles of GMCs in forming neointima in AVFs remain unknown. GMCs isolated from CKD mice showed increased potential capacity of differentiation into myofibroblast-like cells. Increased activation of expression of PDGFRA and hedgehog (HH) signaling were detected in adventitial cells of AVFs from patients with end-stage kidney disease and CKD mice. PDGFRA was translocated and accumulated in early endosome when sonic hedgehog was overexpressed. In endosome, PDGFRA-mediated activation of TGFB1/SMAD signaling promoted the differentiation of GMCs into myofibroblasts, extracellular matrix deposition, and vascular fibrosis. These responses resulted in neointima formation and AVF failure. KO of Pdgfra or inhibition of HH signaling in GMCs suppressed the differentiation of GMCs into myofibroblasts. In vivo, specific KO of Pdgfra inhibited GMC activation and vascular fibrosis, resulting in suppression of neointima formation and improvement of AVF patency despite CKD. Our findings could yield strategies for maintaining AVF functions.


Asunto(s)
Fístula Arteriovenosa/patología , Células Madre Mesenquimatosas/patología , Músculo Liso Vascular/patología , Miofibroblastos/patología , Neointima/patología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Insuficiencia Renal Crónica/complicaciones , Animales , Fístula Arteriovenosa/etiología , Fístula Arteriovenosa/metabolismo , Diferenciación Celular , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Músculo Liso Vascular/metabolismo , Miofibroblastos/metabolismo , Neointima/etiología , Neointima/metabolismo
3.
PLoS One ; 15(7): e0236741, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32730300

RESUMEN

Aryl hydrocarbon receptor (AHR) agonists such as dioxin have been associated with obesity and the development of diabetes. Whole-body Ahr knockout mice on high-fat diet (HFD) have been shown to resist obesity and hepatic steatosis. Tissue-specific knockout of Ahr in mature adipocytes via adiponectin-Cre exacerbates obesity while knockout in liver increases steatosis without having significant effects on obesity. Our previous studies demonstrated that treatment of subcutaneous preadipocytes with exogenous or endogenous AHR agonists disrupts maturation into functional adipocytes in vitro. Here, we used platelet-derived growth factor receptor alpha (Pdgfrα)-Cre mice, a Cre model previously established to knock out genes in preadipocyte lineages and other cell types, but not liver cells, to further define AHR's role in obesity. We demonstrate that Pdgfrα-Cre Ahr-floxed (Ahrfl/fl) knockout mice are protected from HFD-induced obesity compared to non-knockout Ahrfl/fl mice (control mice). The Pdgfrα-Cre Ahrfl/fl knockout mice were also protected from increased adiposity, enlargement of adipocyte size, and liver steatosis while on the HFD compared to control mice. On a regular control diet, knockout and non-knockout mice showed no differences in weight gain, indicating the protective phenotype arises only when animals are challenged by a HFD. At the cellular level, cultured cells from brown adipose tissue (BAT) of Pdgfrα-Cre Ahrfl/fl mice were more responsive than cells from controls to transcriptional activation of the thermogenic uncoupling protein 1 (Ucp1) gene by norepinephrine, suggesting an ability to burn more energy under certain conditions. Collectively, our results show that knockout of Ahr mediated by Pdgfrα-Cre is protective against diet-induced obesity and suggest a mechanism by which enhanced UCP1 activity within BAT might confer these effects.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/fisiología , Dieta Alta en Grasa/efectos adversos , Hígado Graso/prevención & control , Integrasas/metabolismo , Obesidad/prevención & control , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Receptores de Hidrocarburo de Aril/fisiología , Adiposidad , Animales , Metabolismo Energético , Hígado Graso/etiología , Hígado Graso/patología , Femenino , Resistencia a la Insulina , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/etiología , Obesidad/patología , Termogénesis
4.
J Neurosurg ; 134(5): 1535-1543, 2020 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-32442967

RESUMEN

OBJECTIVE: This study aimed to clarify the underlying mechanism of pathognomonic angiogenesis between the temporal muscle and neocortex after indirect bypass for moyamoya disease by shedding light on the role of platelet-derived growth factor receptor-α (PDGFRα) in angiogenesis. METHODS: The gene for PDGFRα was systemically inactivated in adult mice (α-KO mice). The Pdgfra-preserving mice (Flox mice) and α-KO mice were exposed to bilateral common carotid artery stenosis (BCAS) by using microcoils. One week later the animals underwent encephalomyosynangiosis (EMS) on the right side. Cerebral blood flow (CBF) was serially measured using a laser Doppler flowmeter. Histological analysis was performed on the distribution of CD31-positive vessels and collagen deposit at 28 days after BCAS. Reverse transcription polymerase chain reaction (RT-PCR) was performed to assess the expression of collagen mRNA in the skin fibroblasts derived from Flox and α-KO mice. RESULTS: BCAS significantly reduced CBF up to approximately 70% of the control level at 28 days after the onset. There was no significant difference in CBF between Flox and α-KO mice. EMS significantly enhanced the improvement of CBF on the ipsilateral side of Flox mice, but not α-KO mice. EMS significantly induced the development of CD31-positive vessels in both the neocortex and temporal muscle on the ipsilateral side of Flox mice, but not α-KO mice. Deposition of collagen was distinctly observed between them in Flox mice, but not α-KO mice. Expression of mRNA of collagen type 1 alpha 1 (Col1a1) and collagen type 3 alpha 1 (Col3a1) was significantly downregulated in the skin fibroblasts from α-KO mice. CONCLUSIONS: This is the first study that denotes the role of a specific growth factor in angiogenesis after EMS for moyamoya disease by inactivating its gene in mice. The findings strongly suggest that PDGFRα signal may play an important role in developing spontaneous angiogenesis between the temporal muscle and neocortex after EMS in moyamoya disease.


Asunto(s)
Estenosis Carotídea/fisiopatología , Revascularización Cerebral/métodos , Modelos Animales de Enfermedad , Enfermedad de Moyamoya , Neovascularización Fisiológica/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Animales , Estenosis Carotídea/cirugía , Circulación Cerebrovascular , Colágeno Tipo I/biosíntesis , Colágeno Tipo I/genética , Cadena alfa 1 del Colágeno Tipo I , Colágeno Tipo III/biosíntesis , Colágeno Tipo III/genética , Femenino , Fibroblastos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neocórtex/irrigación sanguínea , ARN Mensajero/biosíntesis , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Músculo Temporal/irrigación sanguínea
5.
FEBS Open Bio ; 10(5): 767-779, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32128992

RESUMEN

Osteosarcoma is the most common malignant bone tumor in adolescence and childhood. Metastatic osteosarcoma has a poor prognosis with an overall 5-year survival rate of approximately 20%. TAS-115 is a novel multiple receptor tyrosine kinase inhibitor that is currently undergoing clinical trials. Using the mouse highly lung-metastatic osteosarcoma cell line, LM8, we showed that TAS-115 suppressed the growth of subcutaneous grafted tumor and lung metastasis of osteosarcoma at least partially through the inhibition of platelet-derived growth factor receptor alpha, AXL, and Fms-like tyrosine kinase 3 phosphorylation. We also show that these signaling pathways are activated in various human osteosarcoma cell lines and are involved in proliferation. Our results suggest that TAS-115 may have potential for development into a novel treatment for metastatic osteosarcoma.


Asunto(s)
Osteosarcoma/metabolismo , Quinolinas/farmacología , Tiourea/análogos & derivados , Animales , Neoplasias Óseas/patología , Neoplasias Óseas/secundario , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Neoplasias Pulmonares , Ratones , Ratones Endogámicos C3H , Osteosarcoma/genética , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-met/metabolismo , Quinolinas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Tirosina Quinasas Receptoras/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Transducción de Señal/efectos de los fármacos , Tiourea/metabolismo , Tiourea/farmacología , Tirosina Quinasa 3 Similar a fms/metabolismo , Tirosina Quinasa 3 Similar a fms/fisiología , Tirosina Quinasa del Receptor Axl
6.
Clin Nephrol ; 93(4): 195-202, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32049626

RESUMEN

AIM: By observing the expression and distribution of platelet-derived growth factor receptor α-positive (PDGFRα+) cells in ureteropelvic junction obstruction (UPJO), to explore their role in the pathogenesis of children with congenital hydronephrosis. MATERIALS AND METHODS: The control group involved specimens of the normal ureter (nephrectomy for tumor; n = 10), and the UPJO group contained specimens of ureteropelvic junction (UPJ) segment excised during pyeloplasty (n = 30). The specimens were investigated using immunofluorescence for the expression and distribution of PDGFRα+ cells in each group by light microscopy with computerized image analysis. Real-time PCR (RT-PCR) was used to study PDGFRα gene expression levels. In addition, small conductance calcium-activated potassium channel 3 (SK3) and closely associated cells consisting of smooth muscle cells (SMCs), interstitial cells of Cajal (ICCs), and nerve fibers were investigated. RESULTS: PDGFRα+ cells were in close proximity to SMCs, ICCs, and nerve fibers. PDGFRα+ cells expressed SK3 channels, which are found to regulate purinergic inhibitory neurotransmission in SMCs. Regarding the expression of PDGFRα+ cells no significant difference was seen between the two groups, while the expression of SK3 channels in PDGFRα+ cells was significantly decreased in the UPJO group versus the control group. CONCLUSION: This study identified the expression of PDGFRα+ cells in the human UPJ. Our results demonstrate the expression of SK3 channels in PDGFRα+ cells was decreased in UPJO, and SK3 channels may be involved in the pathogenesis of UPJO by perturbing the UPJ peristalsis.


Asunto(s)
Pelvis Renal/patología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/análisis , Uréter/patología , Obstrucción Ureteral/etiología , Niño , Preescolar , Constricción Patológica , Humanos , Lactante , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/fisiología
7.
FASEB J ; 34(4): 5563-5577, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32086857

RESUMEN

Transcriptome data revealed α1 adrenoceptors (ARs) expression in platelet-derived growth factor receptor α+ cells (PDGFRα+ cells) in murine colonic musculature. The role of PDGFRα+ cells in sympathetic neural regulation of murine colonic motility was investigated. Norepinephrine (NE), via α1A ARs, activated a small conductance Ca2+ -activated K+ (SK) conductance, evoked outward currents and hyperpolarized PDGFRα+ cells (the α1A AR-SK channel signal pathway). α1 AR agonists increased intracellular Ca2+ transients in PDGFRα+ cells and inhibited spontaneous phasic contractions (SPCs) of colonic muscle through activation of a SK conductance. Sympathetic nerve stimulation inhibited both contractions of distal colon and propulsive contractions represented by the colonic migrating motor complexes (CMMCs) via the α1A AR-SK channel signal pathway. Postsynaptic signaling through α1A ARs in PDGFRα+ cells is a novel mechanism that conveys part of stress responses in the colon. PDGFRα+ cells appear to be a primary effector of sympathetic neural regulation of murine colonic motility.


Asunto(s)
Colon/fisiología , Músculo Liso/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Receptores Adrenérgicos alfa 1/metabolismo , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/metabolismo , Sistema Nervioso Simpático/fisiología , Potenciales Sinápticos , Adenosina Trifosfato , Animales , Calcio/metabolismo , Colon/citología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Músculo Liso/citología , Transducción de Señal , Sistema Nervioso Simpático/citología
8.
Neurosci Lett ; 715: 134594, 2020 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-31678431

RESUMEN

White matter lesions are associated with impairment of the blood-brain barrier (BBB), an essential component of the cerebrovasculature. The BBB allows the brain to maintain its highly specialized microenvironment by restricting entry of blood-borne substances including molecules that induce myelin damage. Accumulating evidence suggests that interactions between brain endothelial cells and neighboring cells, including oligodendrocyte progenitor cells (OPCs), are required for the induction and maintenance of BBB function. Here, we compared the ability of OPCs and oligodendrocytes to modulate BBB integrity using co-cultures of rat brain endothelial cells with OPCs or oligodendrocytes. We found that OPCs lowered the brain endothelial permeability to sodium fluorescein, and this enhancement of BBB function was prevented by treatment with AG1296 (a PDGFRα inhibitor). Oligodendrocytes also enhanced BBB integrity. Pharmacological inhibition of PDGFRα did not affect the oligodendrocyte-induced BBB facilitation. These data indicate that oligodendrocytes enhance BBB integrity through pathways other than PDGF-BB/PDGFRα signaling triggered by the brain endothelial cell-derived PDGF-BB. Therefore, our findings suggest that oligodendrocytes constitutively support BBB integrity through soluble factors. Crosstalk between brain endothelial cells and oligodendrocytes could play a facilitatory role in maintaining BBB integrity in the white matter.


Asunto(s)
Becaplermina/fisiología , Barrera Hematoencefálica/fisiología , Células Endoteliales/fisiología , Células Precursoras de Oligodendrocitos/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Transducción de Señal/fisiología , Animales , Barrera Hematoencefálica/citología , Barrera Hematoencefálica/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Células Cultivadas , Técnicas de Cocultivo , Células Endoteliales/efectos de los fármacos , Células Precursoras de Oligodendrocitos/efectos de los fármacos , Oligodendroglía/efectos de los fármacos , Oligodendroglía/fisiología , Ratas , Ratas Wistar , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Tirfostinos/farmacología
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 38(3): 274-282, 2018 Mar 20.
Artículo en Chino | MEDLINE | ID: mdl-29643032

RESUMEN

OBJECTIVE: To investigate the regulatory role of classical Shh signaling pathway in the development of the epithelium and mesenchyme (bronchial cartilage and smooth muscles) during lung development in fetal mice. METHODS: Immunohistochemical technique was used to detect the expression of Shh signaling pathway receptor Smo and Pdgfr-α in murine fetal lungs to explore the spatial and temporal characteristics of their expression. Based on the interstitial specificity of Pdgfr-α expression, we constructed a Pdgfr-α-cre to establish a E12.5 - E16.5 transgenic mice with specific knockout of the key Shh signaling molecule Smo in the pulmonary interstitium with tamoxifen induction. Immunofluorescence technique was used to observe the epithelium and mesenchyme (bronchial cartilage and smooth muscle) during fetal lung development in the transgenic mice to assess the role of Shh signaling pathway in the epithelial-to-mesenchymal (EMT) transition during the lung development. RESULTS: Smo was highly expressed in the epithelial and stromal lung tissues in the pseudoglandular stage and was gradually lowered over time with its distribution mainly in the interstitial tissues. Pdgfr-α was enriched in the distal lung epithelial and mesenchy tissues in early embryonic lungs and gradually migrated to the proximal stroma until becoming concentrated around the main bronchial proximal stroma. We successfully specific established mouse models of specific mesenchymal Smo knockout. Compared with the control group, the transgenic mice during E12.5-E16.5 showed significantly reduced lung the volume and bronchial branching with also decreased expression of the proximal epithelial P63 (P<0.05). The transgenic mice exhibited alterations in the expression of α-smooth muscle actin with delayed bronchial cartilage development and decreased expression of mucoprotein. CONCLUSION: The temporospatial specific expression of Shh signaling pathway plays an important role in developmental regulation of mouse embryonic lung epithelium and mesenchyme (bronchial cartilage and smooth muscle).


Asunto(s)
Epitelio/embriología , Proteínas Hedgehog/fisiología , Pulmón/embriología , Transducción de Señal , Animales , Transición Epitelial-Mesenquimal , Ratones , Ratones Noqueados , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Receptor Smoothened/genética , Receptor Smoothened/fisiología
10.
Proc Natl Acad Sci U S A ; 115(14): E3173-E3181, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29559533

RESUMEN

Wnts and R-spondins (RSPOs) support intestinal homeostasis by regulating crypt cell proliferation and differentiation. Ex vivo, Wnts secreted by Paneth cells in organoids can regulate the proliferation and differentiation of Lgr5-expressing intestinal stem cells. However, in vivo, Paneth cell and indeed all epithelial Wnt production is completely dispensable, and the cellular source of Wnts and RSPOs that maintain the intestinal stem-cell niche is not known. Here we investigated both the source and the functional role of stromal Wnts and RSPO3 in regulation of intestinal homeostasis. RSPO3 is highly expressed in pericryptal myofibroblasts in the lamina propria and is several orders of magnitude more potent than RSPO1 in stimulating both Wnt/ß-catenin signaling and organoid growth. Stromal Rspo3 ablation ex vivo resulted in markedly decreased organoid growth that was rescued by exogenous RSPO3 protein. Pdgf receptor alpha (PdgfRα) is known to be expressed in pericryptal myofibroblasts. We therefore evaluated if PdgfRα identified the key stromal niche cells. In vivo, Porcn excision in PdgfRα+ cells blocked intestinal crypt formation, demonstrating that Wnt production in the stroma is both necessary and sufficient to support the intestinal stem-cell niche. Mice with Rspo3 excision in the PdgfRα+ cells had decreased intestinal crypt Wnt/ß-catenin signaling and Paneth cell differentiation and were hypersensitive when stressed with dextran sodium sulfate. The data support a model of the intestinal stem-cell niche regulated by both Wnts and RSPO3 supplied predominantly by stromal pericryptal myofibroblasts marked by PdgfRα.


Asunto(s)
Células Epiteliales/citología , Intestinos/citología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Nicho de Células Madre/fisiología , Células Madre/citología , Células del Estroma/citología , Trombospondinas/metabolismo , Proteína Wnt1/metabolismo , Aciltransferasas/fisiología , Animales , Diferenciación Celular , Proliferación Celular , Células Epiteliales/metabolismo , Homeostasis , Mucosa Intestinal/metabolismo , Proteínas de la Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Organoides/citología , Organoides/metabolismo , Células Madre/metabolismo , Células del Estroma/metabolismo , Trombospondinas/genética , Proteína Wnt1/genética
11.
Biochim Biophys Acta Rev Cancer ; 1868(2): 372-393, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28669749

RESUMEN

Extracellular vesicle (EV) production is a universal feature of metazoan cells as well as prokaryotes (bMVs - bacterial microvesicles). They are small vesicles with phospholipid membrane carrying proteins, DNA and different classes of RNAs and are heavily involved in intercellular communication acting as vectors of information to target cells. For the last decade, the interest in EV research has exponentially increased though thorough studies of their roles in various pathologies that was not previously possible due to technical limitations. This review focuses on research evaluating the role of EV production in gastrointestinal (GI) cancer development in conjunction with GI microbiota and inflammatory diseases. We also discuss recent studies on the promising role of EVs and their content as biomarkers for early diagnosis of GI cancers. The bMVs have also been implicated in the pathogenesis of GI chronic inflammatory diseases, however, possible role of bMVs in tumorigenesis remains underestimated. We propose that EVs from eukaryotic cells as well as from different microbial, fungi, parasitic species and edible plants in GI tract act as mediators of intracellular and inter-species communication, particularly facilitating tumor cell survival and multi-drug resistance. In conclusion, we suggest that matching sequences from EV proteomes (available from public databases) with known protein sequences of microbiome gut bacteria will be useful in identification of antigen mimicry between evolutionary conservative protein sequences. Using this approach we identified Bacteroides spp. pseudokinase with activation loop and homology to PDGFRα, providing a proof-of-concept strategy. We speculate that existence of microbial pseudokinase that 'mimics' PDGFRα may be related to PDGFRα and Bacteroides spp. roles in colorectal carcinogenesis that require further investigation.


Asunto(s)
Vesículas Extracelulares/fisiología , Microbioma Gastrointestinal/fisiología , Neoplasias Gastrointestinales/etiología , Animales , Comunicación Celular , Humanos , Imitación Molecular , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología
12.
Invest Ophthalmol Vis Sci ; 58(2): 1179-1186, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28245298

RESUMEN

Purpose: The goal of this study was to examine the mechanism behind the unique differential action of transforming growth factor ß3 (TGF-ß3) and TGF-ß1 on SMA expression. It was our hypothesis that platelet-derived growth factor receptor α (PDGFRα) played a key role in determining TGF-ß3's response to wounding. Methods: A stable cell line, human corneal fibroblast (HCF)-P, was created from HCFs by knocking down PDGFRα expression using a lentivirus-delivered shRNA sequence. A three-dimensional (3D) in vitro model was constructed by culturing HCF or HCF-P on poly-transwell membranes for 4 weeks in the presence and absence of 0.1 ng/mL TGF-ß1 or -ß3. At the end of 4 weeks, the constructs were processed for immunofluorescence and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, HCF and HCF-P cell migration was evaluated. Results: In HCF, TGF-ß3 treatment resulted in significantly lower α-smooth muscle actin (SMA) mRNA expression and immunolocalization when compared to TGF-ß1, while in HCF-P, both TGF-ß1 and -ß3 treatment increased the SMA mRNA expression and immunolocalization compared to both the untreated HCF-P control and TGF-ß3-treated HCF. Human corneal fibroblast-P also had a lower migration rate and construct thickness when compared to HCF. Conclusions: These results show that TGF-ß3 decreases SMA in HCF, while remarkably increasing SMA in HCF-P, thus indicating that the presence or absence of PDGFRα elicits contrasting responses to the same TGF-ß3 treatment. Understanding the role of PDGFRα in TGF-ß3's ability to stimulate SMA may potentially help in understanding the differential functions of TGF-ß1 and TGF-ß3 in corneal wound healing.


Asunto(s)
Actinas/metabolismo , Córnea/citología , Fibroblastos/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Factor de Crecimiento Transformador beta1/fisiología , Factor de Crecimiento Transformador beta3/fisiología , Análisis de Varianza , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Fibroblastos/efectos de los fármacos , Humanos , Reacción en Cadena de la Polimerasa , Factor de Crecimiento Transformador beta1/farmacología , Factor de Crecimiento Transformador beta3/farmacología , Cicatrización de Heridas/fisiología
13.
Development ; 144(1): 83-94, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28049691

RESUMEN

Adipose tissue is distributed in depots throughout the body with specialized roles in energy storage and thermogenesis. PDGFRα is a marker of adipocyte precursors, and increased PDGFRα activity causes adipose tissue fibrosis in adult mice. However, the function of PDGFRα during adipose tissue organogenesis is unknown. Here, by analyzing mice with juxtamembrane or kinase domain point mutations that increase PDGFRα activity (V561D or D842V), we found that PDGFRα activation inhibits embryonic white adipose tissue organogenesis in a tissue-autonomous manner. By lineage tracing analysis, we also found that collagen-expressing precursor fibroblasts differentiate into white adipocytes in the embryo. PDGFRα inhibited the formation of adipocytes from these precursors while favoring the formation of stromal fibroblasts. This imbalance between adipocytes and stromal cells was accompanied by overexpression of the cell fate regulator Zfp521. PDGFRα activation also inhibited the formation of juvenile beige adipocytes in the inguinal fat pad. Our data highlight the importance of balancing stromal versus adipogenic cell expansion during white adipose tissue development, with PDGFRα activity coordinating this crucial process in the embryo.


Asunto(s)
Adipocitos/fisiología , Adipogénesis/genética , Tejido Adiposo/embriología , Organogénesis/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Células del Estroma/fisiología , Tejido Adiposo/crecimiento & desarrollo , Tejido Adiposo/fisiología , Sustitución de Aminoácidos , Animales , Animales Recién Nacidos , Linaje de la Célula/genética , Células Cultivadas , Embrión de Mamíferos , Femenino , Lipodistrofia/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutación Puntual , Embarazo
14.
J Pathol ; 240(4): 410-424, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27569721

RESUMEN

Fibrosis is a characteristic of Duchenne muscular dystrophy (DMD), yet the cellular and molecular mechanisms responsible for DMD fibrosis are poorly understood. Utilizing the Collagen1a1-GFP transgene to identify cells producing Collagen-I matrix in wild-type mice exposed to toxic injury or those mutated at the dystrophin gene locus (mdx) as a model of DMD, we studied mechanisms of skeletal muscle injury/repair and fibrosis. PDGFRα is restricted to Sca1+, CD45- mesenchymal progenitors. Fate-mapping experiments using inducible CreER/LoxP somatic recombination indicate that these progenitors expand in injury or DMD to become PDGFRα+, Col1a1-GFP+ matrix-forming fibroblasts, whereas muscle fibres do not become fibroblasts but are an important source of the PDGFRα ligand, PDGF-AA. While in toxin injury/repair of muscle PDGFRα, signalling is transiently up-regulated during the regenerative phase in the DMD model and in human DMD it is chronically overactivated. Conditional expression of the constitutively active PDGFRα D842V mutation in Collagen-I+ fibroblasts, during injury/repair, hindered the repair phase and instead promoted fibrosis. In DMD, treatment of mdx mice with crenolanib, a highly selective PDGFRα/ß tyrosine kinase inhibitor, reduced fibrosis, improved muscle strength, and was associated with decreased activity of Src, a downstream effector of PDGFRα signalling. These observations are consistent with a model in which PDGFRα activation of mesenchymal progenitors normally regulates repair of the injured muscle, but in DMD persistent and excessive activation of this pathway directly drives fibrosis and hinders repair. The PDGFRα pathway is a potential new target for treatment of progressive DMD. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Asunto(s)
Colágeno Tipo I/biosíntesis , Distrofia Muscular de Duchenne/patología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Animales , Bencimidazoles/farmacología , Bencimidazoles/uso terapéutico , Células Cultivadas , Modelos Animales de Enfermedad , Distrofina/genética , Inhibidores Enzimáticos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Fibrosis , Masculino , Ratones Transgénicos , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Distrofia Muscular de Duchenne/tratamiento farmacológico , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Mutación , Piperidinas/farmacología , Piperidinas/uso terapéutico , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Regeneración/efectos de los fármacos , Regeneración/fisiología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
16.
J Urol ; 194(6): 1797-805, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26055827

RESUMEN

PURPOSE: Bladder outlet obstruction is a finding in many urological disorders, leading to bladder wall hyperplasia. We investigated platelet derived growth factor and its receptor in human bladder smooth muscle cells and urothelial cells exposed to hydrostatic pressure or PDGF in vitro. MATERIALS AND METHODS: Bladder smooth muscle cells and urothelial cells were exposed to elevated hydrostatic pressure for 1 hour. The expression of PDGF and PDGFR was evaluated using reverse transcriptase-polymerase chain reaction and Western blot analysis. Pressure or PDGF induced proliferation of bladder smooth muscle cells with or without pretreatment with lovastatin or imatinib was measured by enzyme-linked immunosorbent assay. PDGFRα was knocked down with siRNA. RESULTS: After hydrostatic pressure bladder smooth muscle cells showed increased PDGFRα and ß expression. PDGF was not expressed in bladder smooth muscle cells. Urothelial cells showed no expression of PDGFR but PDGF expression was noted. Western blot analysis of bladder smooth muscle cells revealed a pressure induced increase in PDGFR in the membrane fraction. Phosphorylation of PDGFR occurred with pressure induction. Bladder smooth muscle cell proliferation was increased in pressure and PDGF mediated fashion. Pretreatment with lovastatin or imatinib prevented proliferation. There was no cell proliferation after PDGFRα knockdown. CONCLUSIONS: Increased expression and phosphorylation of PDGFR in bladder smooth muscle cells after hydrostatic pressure suggests a pivotal role of the PDGF pathway in pressure induced hyperplasia of bladder smooth muscle cells. PDGF expressed in urothelial cells may act in a paracrine way. Cholesterol depletion, inhibition of receptor tyrosine kinase activity and knockdown of PDGFRα in bladder smooth muscle cells prevent pressure and PDGF mediated cell proliferation. Targeting PDGFR seems a promising way to influence pressure induced bladder wall hyperplasia.


Asunto(s)
Músculo Liso/patología , Comunicación Paracrina/fisiología , Factor de Crecimiento Derivado de Plaquetas/fisiología , Vejiga Urinaria/patología , Urodinámica/fisiología , Western Blotting , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Proliferación Celular/fisiología , Niño , Técnicas de Silenciamiento del Gen , Humanos , Presión Hidrostática , Hiperplasia , Mesilato de Imatinib/farmacología , Técnicas In Vitro , Lovastatina/farmacología , Músculo Liso/efectos de los fármacos , Comunicación Paracrina/efectos de los fármacos , Comunicación Paracrina/genética , Fosforilación/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/efectos de los fármacos , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Vejiga Urinaria/efectos de los fármacos , Obstrucción del Cuello de la Vejiga Urinaria/genética , Obstrucción del Cuello de la Vejiga Urinaria/patología , Obstrucción del Cuello de la Vejiga Urinaria/fisiopatología
17.
Exp Dermatol ; 24(6): 468-70, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25708924

RESUMEN

Embryonic hair follicle (HF) induction and formation is dependent on signalling crosstalk between the dermis and specialized dermal condensates on the mesenchymal side and epidermal cells and incipient placodes on the epithelial side, but the precise nature and succession of signals remain unclear. Platelet-derived growth factor (PDGF) signalling is involved in the development of several organs and the maintenance of adult tissues, including HF regeneration in the hair cycle. As both PDGF receptors, PDGFRα and PDGFRß, are expressed in embryonic dermis and dermal condensates, we explored in this study the role of PDGF signalling in HF induction and formation in the developing skin mesenchyme. We conditionally ablated both PDGF receptors with Tbx18(Cre) in early dermal condensates before follicle formation, and with Prx1-Cre broadly in the ventral dermis prior to HF induction. In both PDGFR double mutants, HF induction and formation ensued normally, and the pattern of HF formation and HF numbers were unaffected. These data demonstrate that mesenchymal PDGF signalling, either in the specialized niche or broadly in the dermis, is dispensable for HF induction and formation.


Asunto(s)
Dermis/embriología , Folículo Piloso/embriología , Morfogénesis/fisiología , Factor de Crecimiento Derivado de Plaquetas/fisiología , Transducción de Señal/fisiología , Animales , Dermis/citología , Dermis/fisiología , Regulación del Desarrollo de la Expresión Génica , Técnicas de Inactivación de Genes , Folículo Piloso/citología , Folículo Piloso/fisiología , Mesodermo/citología , Mesodermo/embriología , Mesodermo/fisiología , Ratones , Ratones Mutantes , Modelos Animales , Morfogénesis/genética , Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/fisiología , Transducción de Señal/genética
18.
Int Forum Allergy Rhinol ; 4(11): 909-14, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25256824

RESUMEN

BACKGROUND: The pathogenesis of human chronic rhinosinusitis with nasal polyps (CRSwNP) comprising eosinophilic CRSwNP (ECRSwNP) and non-eosinophilic (nECRSwNP) is not completely understood. Recent evidence has suggested that platelet-derived growth factor receptor alpha (PDGFRα) is implicated in cell growth, transformation, proliferation, migration, and vascular permeability and platelet-derived growth factor-A (PDGF-A) is a specific ligand for PDGFRα. However, little is known about their roles in CRSwNP. Therefore, we aimed to investigate the expression and role of PDGFRα and PDGF-A in CRSwNP. METHODS: PDGFRα protein expression was investigated by immunohistochemistry method and messenger RNA (mRNA) expression of PDGFRα and PDGF-A were assessed by real-time polymerase chain reaction (PCR) in CRSwNP patients and control subjects. Moreover, the effects of various stimulators with different concentrations and time on PDGFRα were evaluated on nasal explant culture. RESULTS: Quantitative analysis of immunostaining for PDGFRα showed an obvious elevation in immunolabeling of PDGFRα in CRSwNP groups compared with controls. Furthermore, PDGFRα protein was significantly stronger expressed in ECRSwNP group than nECRSwNP group and atopic patients showed stronger expression of PDGFRα protein than nonatopic patients. The mRNA of PDGFRα and PDGF-A were overexpressed in CRSwNP, especially in ECRSwNP. PDGFRα mRNA expression was closely related to PDGF-A mRNA. In nasal explant culture and stimulation, PDGFRα mRNA was augmented by interleukin 4 (IL-4), IL-5, or IL-1ß respectively, but suppressed by IL-27. CONCLUSION: PDGFRα may play a pivotal role in the pathophysiology of ECRSwNP and nECRSwNP by combining with PDGF-A. IL-4, IL-5, or IL-1ß may be critical for PDGFRα gene expression.


Asunto(s)
Eosinofilia/etiología , Pólipos Nasales/etiología , Factor de Crecimiento Derivado de Plaquetas/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Rinitis/etiología , Sinusitis/etiología , Adulto , Enfermedad Crónica , Femenino , Humanos , Inmunohistoquímica , Interleucinas/farmacología , Masculino , Senos Paranasales/metabolismo , Factor de Crecimiento Derivado de Plaquetas/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/efectos de los fármacos , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Factor de Necrosis Tumoral alfa/farmacología
19.
Am J Physiol Lung Cell Mol Physiol ; 307(8): L618-31, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25150063

RESUMEN

Signaling through platelet-derived growth factor receptor-α (PDGFRα) is required for alveolar septation and participates in alveolar regeneration after pneumonectomy. In both adipose tissue and skeletal muscle, bipotent pdgfrα-expressing progenitors expressing delta-like ligand-1 or sex-determining region Y box 9 (Sox9) may differentiate into either lipid storage cells or myofibroblasts. We analyzed markers of mesenchymal progenitors and differentiation in lung fibroblasts (LF) with different levels (absent, low, or high) of pdgfrα gene expression. A larger proportion of pdgfrα-expressing than nonexpressing LF contained Sox9. Neutral lipids, CD166, and Tcf21 were more abundant in LF with a lower compared with a higher level of pdgfrα gene expression. PDGF-A increased Sox9 in primary LF cultures, suggesting that active signaling through PDGFRα is required to maintain Sox9. As alveolar septation progresses from postnatal day (P) 8 to P12, fewer pdgfrα-expressing LF contain Sox9, whereas more of these LF contain myocardin-like transcription factor-A, showing that Sox9 diminishes as LF become myofibroblasts. At P8, neutral lipid droplets predominate in LF with the lower level of pdgfrα gene expression, whereas transgelin (tagln) was predominantly expressed in LF with higher pdgfrα gene expression. Targeted deletion of pdgfrα in LF, which expressed tagln, reduced Sox9 in α-actin (α-SMA, ACTA2)-containing LF, whereas it increased the abundance of cell surface delta-like protein-1 (as well as peroxisome proliferator-activated receptor-γ and tcf21 mRNA in LF, which also expressed stem cell antigen-1). Thus pdgfrα deletion differentially alters delta-like protein-1 and Sox9, suggesting that targeting different downstream pathways in PDGF-A-responsive LF could identify strategies that promote lung regeneration without initiating fibrosis.


Asunto(s)
Diferenciación Celular , Fibroblastos/citología , Lípidos/fisiología , Proteínas de Microfilamentos/fisiología , Proteínas Musculares/fisiología , Miofibroblastos/citología , Alveolos Pulmonares/citología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Animales , Biomarcadores/análisis , Células Cultivadas , Femenino , Fibroblastos/metabolismo , Citometría de Flujo , Integrasas/metabolismo , Masculino , Ratones , Ratones Noqueados , Miofibroblastos/metabolismo , Fenotipo , Alveolos Pulmonares/metabolismo , Mecánica Respiratoria , Factor de Transcripción SOX9/metabolismo , Transducción de Señal
20.
Ann Hematol ; 93(9): 1473-81, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24763514

RESUMEN

FIP1-like 1 (FIP1L1) is associated with two leukemogenic fusion genes: FIP1L1-retinoic acid receptor alpha (RARA) and FIP1L1-platelet-derived growth factor receptor alpha (PDGFRA). Analyses of a series of deletion mutants revealed that the FIP1 motif in FIP1L1-RARA plays a pivotal role in its homodimerization and transcriptional repressor activity. However, in FIP1L1-PDGFRA, the C-terminal PDGFRA portion possesses the ability of forming a homodimer by itself, making FIP1L1 dispensable for constitutive activation of this kinase. Both the full-length and the C-terminal PDGFRA portion of FIP1L1-PDGFRA could transform the IL-3-dependent hematopoietic cell line, BAF-B03. Moreover, when either the full-length or the C-terminal PDGFRA portion of FIP1L1-PDGFRA was introduced in these cells, they grew in the absence of IL-3. The cells having the C-terminal PDGFRA portion of FIP1L1-PDGFRA, however, were partially IL-3 dependent, whereas the cells having the full-length FIP1L1-PDGFRA became completely IL-3 independent for their growth. Taken together, these results show that FIP1L1 differentially contributes to the pathogenesis of distinct types of leukemia.


Asunto(s)
Leucemia/clasificación , Leucemia/genética , Proteínas de Fusión Oncogénica/fisiología , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/fisiología , Factores de Escisión y Poliadenilación de ARNm/fisiología , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Células HEK293 , Células HeLa , Humanos , Interleucina-3/farmacología , Proteínas de Fusión Oncogénica/química , Dominios y Motivos de Interacción de Proteínas/genética , Multimerización de Proteína/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/química , Factores de Escisión y Poliadenilación de ARNm/química
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