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1.
Lab Chip ; 21(19): 3675-3685, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581719

RESUMO

A pancreatic acinus is a functional unit of the exocrine pancreas producing digest enzymes. Its pathobiology is crucial to pancreatic diseases including pancreatitis and pancreatic cancer, which can initiate from pancreatic acini. However, research on pancreatic acini has been significantly hampered due to the difficulty of culturing normal acinar cells in vitro. In this study, an in vitro model of the normal acinus, named pancreatic acinus-on-chip (PAC), is developed using reprogrammed pancreatic cancer cells. The developed model is a microfluidic platform with an epithelial duct and acinar sac geometry microfabricated by a newly developed two-step controlled "viscous-fingering" technique. In this model, human pancreatic cancer cells, Panc-1, reprogrammed to revert to the normal state upon induction of PTF1a gene expression, are cultured. Bioinformatic analyses suggest that, upon induced PTF1a expression, Panc-1 cells transition into a more normal and differentiated acinar phenotype. The microanatomy and exocrine functions of the model are characterized to confirm the normal acinus phenotypes. The developed model provides a new and reliable testbed to study the initiation and progression of pancreatic cancers.


Assuntos
Pâncreas Exócrino , Neoplasias Pancreáticas , Células Acinares , Humanos , Pâncreas , Neoplasias Pancreáticas/genética , Fatores de Transcrição
2.
Science ; 373(6561): eabj0486, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34529467
3.
Am J Physiol Gastrointest Liver Physiol ; 321(5): G449-G460, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523348

RESUMO

Chronic pancreatitis (CP) is a complex inflammatory disorder with numerous associated genetic and environmental risk factors. The most distressing characteristic of CP is recalcitrant pain, often requiring surgical resection including total pancreatectomy with islet autotransplantation (TPIAT). We studied five consented subjects undergoing pancreatic resection and processed isolated cells for single-cell RNA sequencing (scRNA-Seq). Using high-dimensional transcriptomic cluster analysis, we identified 11 unique cell clusters in the pancreas tissue. These cell clusters include a cluster of undifferentiated/dedifferentiated cells and two unique clusters of acinar cells, one of which appears to be in a transitional stage. To determine the cellular response to protease inhibitor and stimulation, we treated aliquots of cells from one subject with a protease inhibitor cocktail with and without bethanechol (a muscarinic receptor agonist) at 100 and 400 µM and compared gene expression profiles. The protease inhibitors appeared to reduce cell stress. Pancreatic digestive enzymes and islet hormones were upregulated in both doses of bethanechol-treated cells compared with naïve cells. High-dose bethanechol appeared to be toxic and consistent with hyperstimulation. These studies demonstrate the feasibility of investigating human acinar cell physiology at the single-cell level and initial evidence that these cells retain responsiveness to agonist stimulation with predicted second messenger and transcriptomic responses.NEW & NOTEWORTHY We conducted single cell RNA sequencing on pancreas tissue from five individuals. We identified eleven unique cell clusters including a large population of dedifferentiated cells as well as two unique clusters of acinar cells, one of which appears to exist in a transitional state. We also examined the cellular response of pancreas tissue to stimulation and identified affected genes and pathways, including pancreatic digestive enzymes.


Assuntos
Células Acinares/metabolismo , Perfilação da Expressão Gênica , Pâncreas/metabolismo , Pancreatite Crônica/genética , RNA-Seq , Análise de Célula Única , Transcriptoma , Células Acinares/efeitos dos fármacos , Células Acinares/patologia , Desdiferenciação Celular , Análise por Conglomerados , Estudos de Viabilidade , Humanos , Agonistas Muscarínicos/farmacologia , Pâncreas/efeitos dos fármacos , Pâncreas/patologia , Pâncreas/cirurgia , Pancreatectomia , Pancreaticoduodenectomia , Pancreatite Crônica/metabolismo , Pancreatite Crônica/patologia , Pancreatite Crônica/cirurgia , Inibidores de Proteases/farmacologia
4.
Exp Eye Res ; 211: 108760, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34487726

RESUMO

Little is known about the relationship between stimulation of lacrimal gland (LG) tear protein secretion by parasympathetic versus sympathetic nerves, particularly whether the spectrum of tear proteins evoked through each innervation pathway varies. We have previously shown that activity and abundance of cathepsin S (CTSS), a cysteine protease, is greatly increased in tears of Sjögren's syndrome (SS) patients and in tears from the male NOD mouse of autoimmune dacryoadenitis that recapitulates SS-associated dry eye disease. Beyond the increased synthesis of CTSS detected in the diseased NOD mouse LG, increased tear CTSS secretion in NOD mouse tears was recently linked to increased exocytosis from a novel endolysosomal secretory pathway. Here, we have compared secretion and trafficking of CTSS in healthy mouse LG acinar cells stimulated with either the parasympathetic acetylcholine receptor agonist, carbachol (CCh), or the sympathetic α1-adrenergic agonist, phenylephrine (PE). In situ secretion studies show that PE significantly increases CTSS activity and protein in tears relative to CCh stimulation by 1.2-fold (***, p = 0.0009) and ∼5-fold (*, p-0.0319), respectively. A similar significant increase in CTSS activity with PE relative to CCh is observed when cultured LGAC are stimulated in vitro. CCh stimulation significantly elevates intracellular [Ca2+], an effect associated with increases in the size of Rab3D-enriched vesicles consistent with compound fusion, and subsequently decreases in their intensity of labeling consistent with their exocytosis. PE stimulation induces a lower [Ca2+] response and has minimal effects on Rab3D-enriched SV diameter or the intensity of Rab3D-enriched SV labeling. LG deficient in Rab3D exhibit a higher sensitivity to PE stimulation, and secrete more CTSS activity. Significant increases in the colocalization of endolysosomal vesicle markers (Lamp1, Lamp2, Rab7) with the subapical actin suggestive of fusion of endolysosomal vesicles at the apical membrane occur both with CCh and PE stimulation, but PE demonstrates increased colocalization. In conclusion, the α1-adrenergic agonist, PE, increases CTSS secretion into tears through a pathway independent of the exocytosis of Rab3D-enriched mature SV, possibly representing an alternative endolysosomal secretory pathway.


Assuntos
Células Acinares/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos alfa 1/farmacologia , Catepsinas/metabolismo , Aparelho Lacrimal/efeitos dos fármacos , Fenilefrina/farmacologia , Via Secretória/efeitos dos fármacos , Lágrimas/metabolismo , Células Acinares/metabolismo , Animais , Western Blotting , Cálcio/metabolismo , Carbacol/farmacologia , Células Cultivadas , Agonistas Colinérgicos/farmacologia , Modelos Animais de Doenças , Feminino , Inativação Gênica , Aparelho Lacrimal/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , beta-N-Acetil-Hexosaminidases/metabolismo , Proteínas rab3 de Ligação ao GTP/genética
5.
J Histochem Cytochem ; 69(8): 523-534, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34339312

RESUMO

Radiation therapy-mediated salivary gland destruction is characterized by increased inflammatory cell infiltration and fibrosis, both of which ultimately lead to salivary gland hypofunction. However, current treatments (e.g., artificial saliva and sialagogues) only promote temporary relief of symptoms. As such, developing alternative measures against radiation damage is critical for restoring salivary gland structure and function. One promising option for managing radiation therapy-mediated damage in salivary glands is by activation of specialized proresolving lipid mediator receptors due to their demonstrated role in resolution of inflammation and fibrosis in many tissues. Nonetheless, little is known about the presence and function of these receptors in healthy and/or irradiated salivary glands. Therefore, the goal of this study was to detect whether these specialized proresolving lipid mediator receptors are expressed in healthy salivary glands and, if so, if they are maintained after radiation therapy-mediated damage. Our results indicate that specialized proresolving lipid mediator receptors are heterogeneously expressed in inflammatory as well as in acinar and ductal cells within human submandibular glands and that their expression persists after radiation therapy. These findings suggest that epithelial cells as well as resident immune cells represent potential targets for modulation of resolution of inflammation and fibrosis in irradiated salivary glands.


Assuntos
Tolerância a Radiação , Receptores de Quimiocinas/genética , Receptores de Formil Peptídeo/genética , Receptores Acoplados a Proteínas G/genética , Receptores do Leucotrieno B4/genética , Receptores de Lipoxinas/genética , Glândula Submandibular/efeitos da radiação , Células Acinares/citologia , Células Acinares/metabolismo , Células Acinares/efeitos da radiação , Adulto , Idoso , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Células Endoteliais/efeitos da radiação , Feminino , Raios gama , Expressão Gênica , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Receptores de Quimiocinas/metabolismo , Receptores de Formil Peptídeo/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores do Leucotrieno B4/metabolismo , Receptores de Lipoxinas/metabolismo , Glândula Submandibular/citologia , Glândula Submandibular/metabolismo
6.
Trends Endocrinol Metab ; 32(11): 842-845, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34373155

RESUMO

The widespread extrapulmonary complications of coronavirus disease 2019 (COVID-19) have gained momentum; the pancreas is another major target for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we take a closer look into potential pathological interactions. We provide an overview of the current knowledge and understanding of SARS-CoV-2 infection of the pancreas with a special focus on pancreatic islets and propose direct, indirect, and systemic mechanisms for pancreas injury as result of the COVID-19-diabetes fatal bidirectional relationship.


Assuntos
COVID-19/metabolismo , Diabetes Mellitus/metabolismo , Células Secretoras de Insulina/metabolismo , Células Acinares/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Células Secretoras de Glucagon/metabolismo , Humanos , Ilhotas Pancreáticas/metabolismo , Pâncreas/metabolismo , Receptores de Coronavírus/metabolismo , SARS-CoV-2/metabolismo , Serina Endopeptidases/metabolismo , Tropismo Viral
7.
Korean J Gastroenterol ; 78(2): 138-143, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34446637

RESUMO

Acinar cell cystadenoma, also known as an acinar cystic transformation of the pancreas, is an exceedingly rare but benign pancreatic lesion. A 51-year-old woman was transferred to Inje University Busan Paik Hospital because of an 8 cm-sized calcified, multiseptated, and multilocular cystic mass in the pancreatic tail observed during abdominal CT performed at another hospital. The patient did not complain of abdominal pain or other symptoms, and her laboratory findings were normal. MRI showed that the cyst was not connected to the main pancreatic duct. A pancreatic serous cystadenoma was suspected, and a laparoscopic distal pancreatectomy was performed. The resected mass was composed of variable sized multilocular cysts with incomplete septa and focally lined by epithelium with acinar differentiation. The patient was diagnosed with acinar cell cystadenoma and is currently being followed up regularly. No complications or recurrences have been observed.


Assuntos
Cistadenoma Seroso , Cistadenoma , Neoplasias Pancreáticas , Células Acinares , Cistadenoma/diagnóstico , Cistadenoma/cirurgia , Cistadenoma Seroso/diagnóstico , Cistadenoma Seroso/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia
8.
Biochem Biophys Res Commun ; 572: 72-79, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34358966

RESUMO

Hypoxia-inducible factor-1α (Hif1α) is activated in hypoxia and is closely related to oxidative stress, immunity and cell metabolism. Recently, it is reported that Hif1α is involved in atherosclerosis, ischemia-reperfusion (I/R) injury, alcoholic liver disease and pancreatic tumors. In this study, we found that Hif1 signal pathway is significantly changed in pancreas of acute pancreatitis (AP) mice. Meanwhile, we verified that the high expression of Hif1α injured pancreatic tissues of cerulean-induced AP mice, which prompting that Hif1α participated in the progress of histopathology on AP. We applied a Hif1α inhibitor PX478 and observed that it could alleviate histological injury of pancreas as well as the levels of serum amylase, lipase and proinflammatory cytokine in the murine model of AP induced by caerulein. In addition, PX478 could reduce the formation of necrosome (RIP3 and p-MLKL) and the generation of reactive oxygen species (ROS) in AP mice. Correspondingly, we further confirmed the effectiveness of PX478 in vitro and found that inhibiting Hif1α could mitigated the necrosis of pancreatic acinar cells via reducing the RIP3 and p-MLKL expression and the ROS production. In conclusion, inhibiting Hif1α could protect against acinar cells necrosis in AP, which may provide a new target for the prevention and treatment of AP clinically.


Assuntos
Células Acinares/efeitos dos fármacos , Modelos Animais de Doenças , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Compostos de Mostarda/farmacologia , Necrose/tratamento farmacológico , Pancreatite/tratamento farmacológico , Fenilpropionatos/farmacologia , Células Acinares/metabolismo , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Necrose/metabolismo , Pancreatite/metabolismo
9.
Cell Stem Cell ; 28(11): 2009-2019.e4, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34358441

RESUMO

The tissue dynamics that govern maintenance and regeneration of the pancreas remain largely unknown. In particular, the presence and nature of a cellular hierarchy remains a topic of debate. Previous lineage tracing strategies in the pancreas relied on specific marker genes for clonal labeling, which left other populations untested and failed to account for potential widespread phenotypical plasticity. Here we employed a tracing system that depends on replication-induced clonal marks. We found that, in homeostasis, steady acinar replacement events characterize tissue dynamics, to which all acinar cells have an equal ability to contribute. Similarly, regeneration following pancreatitis was best characterized by an acinar self-replication model because no evidence of a cellular hierarchy was detected. In particular, rapid regeneration in the pancreas was found to be driven by an accelerated rate of acinar fission-like events. These results provide a comprehensive and quantitative model of cell dynamics in the exocrine pancreas.


Assuntos
Pâncreas Exócrino , Pancreatite , Células Acinares , Homeostase , Humanos , Pâncreas
10.
Cells ; 10(8)2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34440877

RESUMO

Saliva secretion requires effective translocation of aquaporin 5 (AQP5) water channel to the salivary glands (SGs) acinar apical membrane. Patients with Sjögren's syndrome (SS) display abnormal AQP5 localization within acinar cells from SGs that correlate with sicca manifestation and glands hypofunction. Several proteins such as Prolactin-inducible protein (PIP) may regulate AQP5 trafficking as observed in lacrimal glands from mice. However, the role of the AQP5-PIP complex remains poorly understood. In the present study, we show that PIP interacts with AQP5 in vitro and in mice as well as in human SGs and that PIP misexpression correlates with an altered AQP5 distribution at the acinar apical membrane in PIP knockout mice and SS hMSG. Furthermore, our data show that the protein-protein interaction involves the AQP5 C-terminus and the N-terminal of PIP (one molecule of PIP per AQP5 tetramer). In conclusion, our findings highlight for the first time the role of PIP as a protein controlling AQP5 localization in human salivary glands but extend beyond due to the PIP-AQP5 interaction described in lung and breast cancers.


Assuntos
Aquaporina 5/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Glândulas Salivares/metabolismo , Síndrome de Sjogren/metabolismo , Células Acinares/metabolismo , Animais , Aquaporina 5/química , Aquaporina 5/genética , Sítios de Ligação , Linhagem Celular , Humanos , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Knockout , Ligação Proteica , Síndrome de Sjogren/genética
11.
Sci Rep ; 11(1): 17220, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446743

RESUMO

Primary cilia protrude from the apical surface of many cell types and act as a sensory organelle that regulates diverse biological processes ranging from chemo- and mechanosensation to signaling. Ciliary dysfunction is associated with a wide array of genetic disorders, known as ciliopathies. Polycystic lesions are commonly found in the kidney, liver, and pancreas of ciliopathy patients and mouse models. However, the pathogenesis of the pancreatic phenotype remains poorly understood. Chibby1 (Cby1), a small conserved coiled-coil protein, localizes to the ciliary base and plays a crucial role in ciliogenesis. Here, we report that Cby1-knockout (KO) mice develop severe exocrine pancreatic atrophy with dilated ducts during early postnatal development. A significant reduction in the number and length of cilia was observed in Cby1-KO pancreta. In the adult Cby1-KO pancreas, inflammatory cell infiltration and fibrosis were noticeable. Intriguingly, Cby1-KO acinar cells showed an accumulation of zymogen granules (ZGs) with altered polarity. Moreover, isolated acini from Cby1-KO pancreas exhibited defective ZG secretion in vitro. Collectively, our results suggest that, upon loss of Cby1, concomitant with ciliary defects, acinar cells accumulate ZGs due to defective exocytosis, leading to cell death and progressive exocrine pancreatic degeneration after birth.


Assuntos
Proteínas de Transporte/genética , Cílios/metabolismo , Pâncreas Exócrino/metabolismo , Pâncreas/metabolismo , Pancreatite/genética , Células Acinares/metabolismo , Animais , Atrofia , Proteínas de Transporte/metabolismo , Ciliopatias/genética , Ciliopatias/metabolismo , Exocitose/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Pâncreas/patologia , Pâncreas/ultraestrutura , Pâncreas Exócrino/patologia , Pancreatite/metabolismo , Vesículas Secretórias/metabolismo
12.
Cells ; 10(8)2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34440749

RESUMO

The cellular mechanisms of basement membrane (BM) invasion remain poorly understood. We investigated the invasion-promoting mechanisms of actin cytoskeleton reorganization in BM-covered MCF10A breast acini. High-resolution confocal microscopy has characterized actin cell protrusion formation and function in response to tumor-resembling ECM stiffness and soluble EGF stimulation. Traction force microscopy quantified the mechanical BM stresses that invasion-triggered acini exerted on the BM-ECM interface. We demonstrate that acini use non-proteolytic actin microspikes as functional precursors of elongated protrusions to initiate BM penetration and ECM probing. Further, these microspikes mechanically widened the collagen IV pores to anchor within the BM scaffold via force-transmitting focal adhesions. Pre-invasive basal cells located at the BM-ECM interface exhibited predominantly cortical actin networks and actin microspikes. In response to pro-invasive conditions, these microspikes accumulated and converted subsequently into highly contractile stress fibers. The phenotypical switch to stress fiber cells matched spatiotemporally with emerging high BM stresses that were driven by actomyosin II contractility. The activation of proteolytic invadopodia with MT1-MMP occurred at later BM invasion stages and only in cells already disseminating into the ECM. Our study demonstrates that BM pore-widening filopodia bridge mechanical ECM probing function and contractility-driven BM weakening. Finally, these EMT-related cytoskeletal adaptations are critical mechanisms inducing the invasive transition of benign breast acini.


Assuntos
Actinas/metabolismo , Membrana Basal/metabolismo , Miosina Tipo II/metabolismo , Fibras de Estresse/metabolismo , Células Acinares/citologia , Células Acinares/metabolismo , Mama/citologia , Mama/metabolismo , Adesão Celular , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Matriz Extracelular/metabolismo , Feminino , Humanos , Microscopia Confocal , Podossomos/metabolismo , Pseudópodes/metabolismo , Fibras de Estresse/química
13.
Elife ; 102021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34240705

RESUMO

Salivary fluid secretion involves an intricate choreography of membrane transporters to result in the trans-epithelial movement of NaCl and water into the acinus lumen. Current models are largely based on experimental observations in enzymatically isolated cells where the Ca2+ signal invariably propagates globally and thus appears ideally suited to activate spatially separated Cl and K channels, present on the apical and basolateral plasma membrane, respectively. We monitored Ca2+ signals and salivary secretion in live mice expressing GCamp6F, following stimulation of the nerves innervating the submandibular gland. Consistent with in vitro studies, Ca2+ signals were initiated in the apical endoplasmic reticulum. In marked contrast to in vitro data, highly localized trains of Ca2+ transients that failed to fully propagate from the apical region were observed. Following stimuli optimum for secretion, large apical-basal gradients were elicited. A new mathematical model, incorporating these data was constructed to probe how salivary secretion can be optimally stimulated by apical Ca2+ signals.


Assuntos
Sinalização do Cálcio/fisiologia , Saliva/metabolismo , Glândulas Salivares/metabolismo , Células Acinares/metabolismo , Animais , Cálcio/metabolismo , Biologia Computacional , Retículo Endoplasmático/metabolismo , Feminino , Canais Iônicos/metabolismo , Masculino , Camundongos , Glândulas Salivares/patologia , Glândula Submandibular
14.
Nat Commun ; 12(1): 4386, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-34282152

RESUMO

Acute pancreatitis (AP) is serious inflammatory disease of the pancreas. Accumulating evidence links diabetes with severity of AP, suggesting that endogenous insulin may be protective. We investigated this putative protective effect of insulin during cellular and in vivo models of AP in diabetic mice (Ins2Akita) and Pancreatic Acinar cell-specific Conditional Insulin Receptor Knock Out mice (PACIRKO). Caerulein and palmitoleic acid (POA)/ethanol-induced pancreatitis was more severe in both Ins2Akita and PACIRKO vs control mice, suggesting that endogenous insulin directly protects acinar cells in vivo. In isolated pancreatic acinar cells, insulin induced Akt-mediated phosphorylation of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2) which upregulated glycolysis thereby preventing POA-induced ATP depletion, inhibition of the ATP-dependent plasma membrane Ca2+ ATPase (PMCA) and cytotoxic Ca2+ overload. These data provide the first mechanistic link between diabetes and severity of AP and suggest that phosphorylation of PFKFB2 may represent a potential therapeutic strategy for treatment of AP.


Assuntos
Células Acinares/metabolismo , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Glicólise/efeitos dos fármacos , Insulina/metabolismo , Insulina/farmacologia , Pancreatite/metabolismo , Substâncias Protetoras/farmacologia , Células Acinares/efeitos dos fármacos , Doença Aguda , Animais , ATPases Transportadoras de Cálcio/metabolismo , Ceruletídeo , Diabetes Mellitus Experimental/metabolismo , Ácidos Graxos Monoinsaturados , Masculino , Camundongos , Camundongos Knockout , Pâncreas/metabolismo , Pancreatite/tratamento farmacológico , Pancreatite/patologia
15.
Cells ; 10(7)2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201461

RESUMO

Cholinergic innervation in the pancreas controls both the release of digestive enzymes to support the intestinal digestion and absorption, as well as insulin release to promote nutrient use in the cells of the body. The effects of muscarinic receptor stimulation are described in detail for endocrine beta cells and exocrine acinar cells separately. Here we describe morphological and functional criteria to separate these two cell types in situ in tissue slices and simultaneously measure their response to ACh stimulation on cytosolic Ca2+ oscillations [Ca2+]c in stimulatory glucose conditions. Our results show that both cell types respond to glucose directly in the concentration range compatible with the glucose transporters they express. The physiological ACh concentration increases the frequency of glucose stimulated [Ca2+]c oscillations in both cell types and synchronizes [Ca2+]c oscillations in acinar cells. The supraphysiological ACh concentration further increases the oscillation frequency on the level of individual beta cells, inhibits the synchronization between these cells, and abolishes oscillatory activity in acinar cells. We discuss possible mechanisms leading to the observed phenomena.


Assuntos
Acetilcolina/farmacologia , Células Acinares/metabolismo , Sinalização do Cálcio , Citosol/metabolismo , Células Secretoras de Insulina/metabolismo , Animais , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Citosol/efeitos dos fármacos , Feminino , Glucose/farmacologia , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Receptores Muscarínicos/metabolismo , Fatores de Tempo
16.
Am J Surg Pathol ; 45(8): 1028-1037, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34091485

RESUMO

Mucoepidermoid carcinoma (MEC) is generally characterized by an admixture of mucous, epidermoid and intermediate type cells. Numerous variants morphologies are described and defined by stromal and/or cytoplasmic tinctorial characteristics. We now report 11 cases of MEC with serous acinar differentiation, reflecting a distal intercalated duct/acinar phenotype, which we designate as mucoacinar carcinomas. Seven patients were female while 4 were male with a mean age of 55 years (range: 21 to 72 y). Ten cases were from the parotid while 1 was from the submandibular gland. Mean size of the tumors was 1.8 cm (range: 0.7 to 4.5 cm). Three cases were low grade, 7 were intermediate grade, and 1 was high grade. Low to intermediate grade cases demonstrated prominent clear to vacuolated cells with focal serous acinar differentiation. The high-grade case showed a distinctive scattering of acinar cells interspersed between epidermoid cells. Periodic acid Schiff after diastase (9/9), SOX-10 (9/9), and DOG-1 (9/10) highlighted the acinar component. Six of 7 cases showed a focal acinar predominant NR4A3 expression. MAML2 fluorescence in situ hybridization was positive in all cases, in both acinar and mucoepidermoid components. Two cases tested by next generation sequencing showed standard CRTC1-MAML2 fusions. MSANTD3 and NR4A3 fluorescence in situ hybridization on the other hand were negative. Evidence thus suggests that mucoacinar carcinoma represents an acinar variant morphology in MEC, rather than a true MEC-acinic cell carcinoma hybrid, or collision tumor. The acinar differentiation, SOX-10, DOG-1, and even focal NR4A3 reactivity may thus be diagnostic pitfalls.


Assuntos
Células Acinares/patologia , Carcinoma Mucoepidermoide/patologia , Neoplasias das Glândulas Salivares/patologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Carcinoma Mucoepidermoide/genética , Carcinoma Mucoepidermoide/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/metabolismo
17.
Cell Stem Cell ; 28(6): 987-988, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34087158

RESUMO

In this issue of Cell Stem Cell, Huang et al. (2021) and Breunig et al. (2021) developed human stem-cell-derived organoid culture systems to recapitulate pancreatic acinar and ductal lineages. This provides opportunities to study cellular plasticity and transformation in pancreatic cancer initiation and progression.


Assuntos
Pâncreas Exócrino , Neoplasias Pancreáticas , Células-Tronco Pluripotentes , Células Acinares , Humanos , Organoides , Pâncreas , Ductos Pancreáticos
18.
J Clin Invest ; 131(15)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34128834

RESUMO

Disordered lysosomal/autophagy pathways initiate and drive pancreatitis, but the underlying mechanisms and links to disease pathology are poorly understood. Here, we show that the mannose-6-phosphate (M6P) pathway of hydrolase delivery to lysosomes critically regulates pancreatic acinar cell cholesterol metabolism. Ablation of the Gnptab gene encoding a key enzyme in the M6P pathway disrupted acinar cell cholesterol turnover, causing accumulation of nonesterified cholesterol in lysosomes/autolysosomes, its depletion in the plasma membrane, and upregulation of cholesterol synthesis and uptake. We found similar dysregulation of acinar cell cholesterol, and a decrease in GNPTAB levels, in both WT experimental pancreatitis and human disease. The mechanisms mediating pancreatic cholesterol dyshomeostasis in Gnptab-/- and experimental models involve a disordered endolysosomal system, resulting in impaired cholesterol transport through lysosomes and blockage of autophagic flux. By contrast, in Gnptab-/- liver the endolysosomal system and cholesterol homeostasis were largely unaffected. Gnptab-/- mice developed spontaneous pancreatitis. Normalization of cholesterol metabolism by pharmacologic means alleviated responses of experimental pancreatitis, particularly trypsinogen activation, the disease hallmark. The results reveal the essential role of the M6P pathway in maintaining exocrine pancreas homeostasis and function, and implicate cholesterol disordering in the pathogenesis of pancreatitis.


Assuntos
Células Acinares/metabolismo , Colesterol/metabolismo , Manosefosfatos/metabolismo , Pâncreas Exócrino/metabolismo , Pancreatite/metabolismo , Células Acinares/patologia , Animais , Colesterol/genética , Modelos Animais de Doenças , Humanos , Manosefosfatos/genética , Camundongos , Camundongos Knockout , Pâncreas Exócrino/patologia , Pancreatite/patologia , Transferases (Outros Grupos de Fosfato Substituídos)/deficiência , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
19.
J Virol ; 95(17): e0069321, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34132572

RESUMO

The cytomegaloviruses (CMVs) spread systemically via myeloid cells and demonstrate broad tissue tropism. Human CMV (HCMV) UL128 encodes a component of the virion pentameric complex (PC) that is important for entry into epithelial cells and cell-cell spread in vitro. It possesses N-terminal amino acid sequences similar to those of CC chemokines. While the species specificity of HCMV precludes confirmation of UL128 function in vivo, UL128-like counterparts in experimental animals have demonstrated a role in salivary gland infection. How they achieve this has not been defined, although effects on monocyte tropism and immune evasion have been proposed. By tracking infected cells following lung infection, we show that although the UL128-like protein in mouse CMV (MCMV) (designated MCK-2) facilitated entry into lung macrophages, it was dispensable for subsequent viremia mediated by CD11c+ dendritic cells (DCs) and extravasation to the salivary glands. Notably, MCK-2 was important for the transfer of MCMV infection from DCs to salivary gland acinar epithelial cells. Acinar cell infection of MCMVs deleted of MCK-2 was not rescued by T-cell depletion, arguing against an immune evasion mechanism for MCK-2 in the salivary glands. In contrast to lung infection, peritoneal MCMV inoculation yields mixed monocyte/DC viremia. In this setting, MCK-2 again promoted DC-dependent infection of salivary gland acinar cells, but it was not required for monocyte-dependent spread to the lung. Thus, the action of MCK-2 in MCMV spread was specific to DC-acinar cell interactions. IMPORTANCE Cytomegaloviruses (CMVs) establish myeloid cell-associated viremias and persistent shedding from the salivary glands. In vitro studies with human CMV (HCMV) have implicated HCMV UL128 in epithelial tropism, but its role in vivo is unknown. Here, we analyzed how a murine CMV (MCMV) protein with similar physical properties, designated MCK-2, contributes to host colonization. We demonstrate that MCK-2 is dispensable for initial systemic spread from primary infection sites but within the salivary gland facilitates the transfer of infection from dendritic cells (DCs) to epithelial acinar cells. Virus transfer from extravasated monocytes to the lungs did not require MCK-2, indicating a tissue-specific effect. These results provide new information about how persistent viral tropism determinants operate in vivo.


Assuntos
Células Acinares/virologia , Quimiocinas CC/metabolismo , Células Dendríticas/virologia , Infecções por Herpesviridae/virologia , Muromegalovirus/fisiologia , Glândulas Salivares/virologia , Proteínas Virais/metabolismo , Replicação Viral , Células Acinares/metabolismo , Animais , Quimiocinas CC/genética , Células Dendríticas/metabolismo , Feminino , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/metabolismo , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Camundongos , Camundongos Endogâmicos BALB C , Glândulas Salivares/metabolismo , Proteínas Virais/genética , Vírion , Internalização do Vírus
20.
Sci Rep ; 11(1): 12614, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131249

RESUMO

In the adult pancreas, the presence of progenitor or stem cells and their potential involvement in homeostasis and regeneration remains unclear. Here, we identify that SET domain-containing protein 4 (SETD4), a histone lysine methyltransferase, is expressed in a small cell population in the adult mouse pancreas. Genetic lineage tracing shows that during pancreatic development, descendants of SETD4+ cells make up over 70% of pancreatic cells and then contribute to each pancreatic lineage during pancreatic homeostasis. SETD4+ cells generate newborn acinar cells in response to cerulein-induced pancreatitis in acinar compartments. Ablation of SETD4+ cells compromises regeneration of acinar cells, in contrast to controls. Our findings provide a new cellular narrative for pancreatic development, homeostasis and response to injury via a small SETD4+ cell population. Potential applications may act to preserve pancreatic function in case of pancreatic disease and/or damage.


Assuntos
Metiltransferases/genética , Pâncreas/metabolismo , Pancreatite/genética , Regeneração/genética , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Linhagem da Célula/genética , Ceruletídeo/toxicidade , Modelos Animais de Doenças , Homeostase/efeitos dos fármacos , Homeostase/genética , Humanos , Camundongos , Pâncreas/crescimento & desenvolvimento , Pâncreas/lesões , Pâncreas/patologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
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