scholarly journals Human intestinal enteroids with inducible neurogenin-3 expression as a novel model of gut hormone secretion

2019 ◽  
Author(s):  
Alexandra L. Chang-Graham ◽  
Heather A. Danhof ◽  
Melinda A. Engevik ◽  
Catherine Tomaro-Duchesneau ◽  
Umesh C. Karandikar ◽  
...  
Keyword(s):  
Hormone Secretion ◽  
Cell Types ◽  
Inducible Expression ◽  
Enteroendocrine Cells ◽  
Neurogenin 3 ◽  
Rotavirus Infection ◽  
Functional Studies ◽  
Gut Hormone ◽  
The Impact

AbstractBackgroundEnteroendocrine cells (EECs) are specialized epithelial cells that produce molecules vital for intestinal homeostasis, but due to their limited numbers, in-depth functional studies have remained challenging. Human intestinal enteroids (HIEs) that are derived from intestinal crypt stem cells are a biologically relevantin vitromodel of the intestinal epithelium. HIEs contain all intestinal epithelial cell types; however, like the intestine, HIEs spontaneously produce few EECs, which limits their study.MethodsTo increase the number of EECs in HIEs, we used lentivirus transduction to stably engineer jejunal HIEs with doxycycline-inducible expression of neurogenin-3 (NGN3), a transcription factor that drives EEC differentiation (tetNGN3-HIEs). We examined the impact ofNGN3induction on EECs by quantifying the increase in the enterochromaffin cells and other EEC subtypes. We functionally assessed secretion of serotonin and EEC hormones in response to norepinephrine and rotavirus infection.ResultsTreating tetNGN3-HIEs with doxycycline induced a dose-dependent increase of chromogranin A (ChgA)-positive and serotonin-positive cells, demonstrating increased enterochromaffin cell differentiation. Despite increased ChgA-positive cells, other differentiated cell types of the epithelium remained largely unchanged by gene expression and immunostaining. RNA sequencing of doxycycline-induced tetNGN3- HIEs identified increased expression of key hormones and enzymes associated with several other EEC subtypes. Doxycycline-induced tetNGN3-HIEs secreted serotonin, monocyte chemoattractant protein-1, glucose-dependent insulinotropic peptide, peptide YY, and ghrelin in response to norepinephrine and rotavirus infection, further supporting the presence of multiple EEC types.ConclusionsWe have combined HIEs and inducible-NGN3expression to establish a flexiblein vitromodel system for functional studies of EECs in enteroids and advance the molecular and physiological investigation of EECs.SynopsisEnteroendocrine cells have low abundance but exert widespread effects on gastrointestinal physiology. We engineered human intestinal enteroids with inducible expression of neurogenin-3, resulting in increased enteroendocrine cells and facilitating investigations of host responses to the dynamic intestinal environment.

scholarly journals The impact of cryopreservation on bone marrow-derived mesenchymal stem cells: a systematic review

2019 ◽  
Vol 17 (1) ◽  
Author(s):  
Soukaina Bahsoun ◽  
Karen Coopman ◽  
Elizabeth C. Akam
Keyword(s):  
Systematic Review ◽  
Stem Cells ◽  
Bone Marrow ◽  
Mesenchymal Stem Cells ◽  
Cell Types ◽  
Surface Marker Expression ◽  
Wide Range ◽  
And Migration ◽  
The Impact

AbstractMesenchymal stem cells (MSCs) represent an invaluable asset for the field of cell therapy. Human Bone marrow-derived MSCs (hBM-MSCs) are one of the most commonly used cell types in clinical trials. They are currently being studied and tested for the treatment of a wide range of diseases and conditions. The future availability of MSCs therapies to the public will require a robust and reliable delivery process. Cryopreservation represents the gold standard in cell storage and transportation, but its effect on BM-MSCs is still not well established. A systematic review was conducted to evaluate the impact of cryopreservation on BM-MSCs and to attempt to uncover the reasons behind some of the controversial results reported in the literature. Forty-one in vitro studies were analysed, and their results organised according to the cell attributes they assess. It was concluded that cryopreservation does not affect BM-MSCs morphology, surface marker expression, differentiation or proliferation potential. However, mixed results exist regarding the effect on colony forming ability and the effects on viability, attachment and migration, genomic stability and paracrine function are undefined mainly due to the huge variabilities governing the cryopreservation process as a whole and to the lack of standardised assays.

Clinical, Pathological, and Molecular Correlates in Ferroportin Disease. A Study of Two Novel Mutations.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 706-706
Author(s):  
Domenico Girelli ◽  
Ivana De Domenico ◽  
Claudia Bozzini ◽  
Ilaria Tenuti ◽  
Nadia Soriani ◽  
...  
Keyword(s):  
Iron Overload ◽  
Cellular Localization ◽  
Transferrin Saturation ◽  
Cell Types ◽  
Mouse Bone Marrow ◽  
Pathological Features ◽  
Functional Studies ◽  
Type Iv

Abstract Background: Mutations in the iron exporter Ferroportin (Fpn) lead to type IV hemochromatosis (Ferroportin Disease, FD), a dominantly inherited disorder with heterogeneous clinical and biochemical patterns. Some patients present with predominant macrophage iron overload (M), marked elevation of serum ferritin, normal-to-low transferrin saturation (TS), and, possibly, iron restricted erythropoiesis. Others present with a phenotype resembling classical HFE-related hemochromatosis, i.e. characterized by high TS and predominant hepatocyte iron overload (H). These differences are thought to reflect heterogeneity in the functional behaviour of Fpn mutant proteins. Methods: Two unrelated probands referring to the Centre for Iron Overload Disorders in Verona because of non-HFE hemochromatosis were screened for Fpn mutations by DHPLC (Cremonesi L, Br J Haematol 2005). The functional behaviour of mutants Fpn was studied by generating Fpn-GFP constructs transfected into different cell types (HEK293T, Cos7, and mouse bone marrow macrophages), and analyzing their cellular localization, as well as their capabilities to bind hepcidin and export iron (De Domenico I, PNAS 2005). The two mutations were also expressed in zebrafish, to evaluate their impact on iron-dependent erythropoiesis. Results: Patient 1, a 59 year old male, had clinical, biochemical (TS 74.8%, ferritin 9,000 μg/l), and pathological features (marked iron overload in either macrophages and hepatocytes, absence of overt cirrhosis) somewhat ambiguous, possibly suggesting a type M Fpn variant with late secondary hepatocyte overload. He was found to be heterozygous for the new L233P mutation. Functional studies revealed that Fpn L233P does not appropriately traffic to the cell surface, resulting in inappropriate inhibition by hepcidin. Fpn L233P expression in vivo in zebrafish resulted in iron limited erythropoiesis, consistent with a type M mutation leading to macrophage iron retention. Patient 2, a 59 year old female, had features more clearly suggesting a type M Fpn variant (TS 22.7%, ferritin 1,771 μg/l, macrophage iron load), but tolerated very well phlebotomies without developing signs of anemia. She was found to be heterozygous for the new I152F mutation. Functional studies revealed a unique pattern (never observed until now), since Fpn I152F localized appropriately on cell membrane, bound near normally to hepcidin, but showed a “primary” deficit of iron export capability. I152F expression in zebrafish resulted in a trend towards iron limited erythropoiesis, though quantitatively less clear than L223P. Conclusions: FD is a heterogeneous disease caused by generally “private” mutations in Fpn. The clinical, biochemical, and pathological features vary depending on the different behaviour of mutant Fpn. In vitro and in vivo molecular expression studies are very useful to clarify the pathophysiogical spectrum of this disease.

scholarly journals miR-96 Regulates Liver Tumor-Initiating Cells Expansion and Sorafenib Resistance

2020 ◽  
Author(s):  
Yonggang Huang ◽  
Jin Zhang ◽  
Wei Dong ◽  
Huiping Peng ◽  
Maolin Gu ◽  
...  
Keyword(s):  
Liver Tumor ◽  
Underlying Mechanism ◽  
Tumor Initiating Cells ◽  
Self Renewal ◽  
Sorafenib Treatment ◽  
Functional Studies ◽  
Optimal Target ◽  
The Impact

Abstract Background Liver tumor-initiating cells (T-ICs) contribute to tumorigenesis, progression, recurrence and drug resistance of hepatocellular carcinoma (HCC). However, the underlying mechanism for the propagation of liver T-ICs remains unclear. Methods Real-time PCR was used to detect the expression of miR-96 in liver tumor-initiating cells (T-ICs). The impact of miR-96 on liver T-ICs expansion was investigated both in vivo and in vitro . The correlation between miR-96 expression and sorafenib benefits in HCC was further evaluated in patient-derived xenografts (PDXs). Results Our finding shows that miR-96 is upregulated in liver T-ICs. Functional studies revealed that forced miR-96 promotes liver T-ICs self-renewal and tumorigenesis. Conversely, knockdown miR-96 inhibits liver T-ICs self-renewal and tumorigenesis. Mechanistically, miR-96 downregulates SOX6 via its mRNA 3’UTR in liver T-ICs. Furthermore, the miR-96 expression determines the responses of hepatoma cells to sorafenib treatment. Analysis of patient-derived xenografts (PDXs) further demonstrated that the miR-96 may predict sorafenib benefits in HCC patients. Conclusion Our findings revealed the crucial role of the miR-96 in liver T-ICs expansion and sorafenib response, rendering miR-96 as an optimal target for the prevention and intervention of HCC.

scholarly journals RNA interference dynamics in juvenile Fasciola hepatica are altered during in vitro growth and development

2020 ◽  
Author(s):  
Paul McCusker ◽  
Wasim Hussain ◽  
Paul McVeigh ◽  
Erin McCammick ◽  
Nathan G. Clarke ◽  
...  
Keyword(s):  
Rna Interference ◽  
Functional Genomics ◽  
Liver Fluke ◽  
Fasciola Hepatica ◽  
Life Stage ◽  
Life Stages ◽  
Functional Studies ◽  
Rnai Efficiency ◽  
The Impact

AbstractFor over a decade RNA interference (RNAi) has been an important molecular tool for functional genomics studies in parasitic flatworms. Despite this, our understanding of RNAi dynamics in many flatworm parasites, such as the temperate liver fluke (Fasciola hepatica), remains rudimentary. The ability to maintain developing juvenile fluke in vitro provides the opportunity to perform functional studies during development of the key pathogenic life stage. Here, we investigate the RNAi competence of developing juvenile liver fluke. Firstly, all life stages examined possess, and express, core candidate RNAi effectors encouraging the hypothesis that all life stages of F. hepatica are RNAi competent. RNAi effector analyses supported growing evidence that parasitic flatworms have evolved a separate clade of RNAi effectors with unknown function. Secondly, we assessed the impact of growth / development during in vitro culture on RNAi in F. hepatica juveniles and found that during the first week post-excystment liver fluke juveniles exhibit quantitatively lower RNAi mediated transcript knockdown when maintained in growth inducing media. This did not appear to occur in older in vitro juveniles, suggesting that rapidly shifting transcript dynamics over the first week following excystment alters RNAi efficacy after a single 24 hour exposure to double stranded (ds)RNA. Finally, RNAi efficiency was found to be improved through use of a repeated dsRNA exposure methodology that has facilitated silencing of genes in a range of tissues, thereby increasing the utility of RNAi as a functional genomics tool in F. hepatica.

scholarly journals Mechanisms controlling hormone secretion in human gut and its relevance to metabolism

2020 ◽  
Vol 244 (1) ◽  
pp. R1-R15 ◽  
Author(s):  
Alyce M Martin ◽  
Emily W Sun ◽  
Damien J Keating
Keyword(s):  
Hormone Secretion ◽  
Enteroendocrine Cells ◽  
Microbial Metabolites ◽  
Human Gut ◽  
Glucose Lowering ◽  
Endocrine Organ ◽  
Metabolic Functions ◽  
Gut Epithelium ◽  
Gut Hormone ◽  
Regulation Of Metabolism

The homoeostatic regulation of metabolism is highly complex and involves multiple inputs from both the nervous and endocrine systems. The gut is the largest endocrine organ in our body and synthesises and secretes over 20 different hormones from enteroendocrine cells that are dispersed throughout the gut epithelium. These hormones include GLP-1, PYY, GIP, serotonin, and CCK, each of which play pivotal roles in maintaining energy balance and glucose homeostasis. Some are now the basis of several clinically used glucose-lowering and weight loss therapies. The environment in which these enteroendocrine cells exist is also complex, as they are exposed to numerous physiological inputs including ingested nutrients, circulating factors and metabolites produced from neighbouring gut microbiome. In this review, we examine the diverse means by which gut-derived hormones carry out their metabolic functions through their interactions with different metabolically important organs including the liver, pancreas, adipose tissue and brain. Furthermore, we discuss how nutrients and microbial metabolites affect gut hormone secretion and the mechanisms underlying these interactions.

scholarly journals Cell proliferation induced by modified cationic dextran

2018 ◽  
Vol 14 (4) ◽  
Author(s):  
Kamil Kamiński ◽  
Krystyna Stalińska ◽  
Anna Niziołek ◽  
Maria Wróbel ◽  
Maria Nowakowska ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Lines ◽  
Positive Impact ◽  
Cell Aggregation ◽  
Fibroblast Cell ◽  
Cell Types ◽  
Cationic Modification ◽  
Diphenyl Tetrazolium Bromide ◽  
The Impact

Abstract The interaction between oppositely charged membranes and polycations causes cell aggregation, loss of membrane fluidity, and membrane degeneration and may cause an increase of its permeability. Unfortunately, the interaction is the reason why the use of polycations in medicine is severely limited. Therefore, in this paper, we share our observations related to the action of 40-kDa dextran modified using glycidyltrimethylammonium chloride, resulting in increased fibroblast cell proliferation. Using viability and proliferation tests [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, crystal violet, 3H-thymidine incorporation], we have observed that cationic dextran derivatives exert a positive impact on nonepithelial cell proliferation in vitro. This phenomenon has been noted for human and mouse fibroblasts and several other nonepithelial cell lines. However, the effect seems to be most pronounced for fibroblast cell lines. The presented studies allow to examine the impact of the polymer structure and the methods of its cationic modification on this newly observed phenomenon. The observation is unique because positively charged macromolecules usually exhibit high toxicity in all cell types in vitro.

scholarly journals Human Intestinal Enteroids With Inducible Neurogenin-3 Expression as a Novel Model of Gut Hormone Secretion

2019 ◽  
Vol 8 (2) ◽  
pp. 209-229 ◽  
Author(s):  
Alexandra L. Chang-Graham ◽  
Heather A. Danhof ◽  
Melinda A. Engevik ◽  
Catherine Tomaro-Duchesneau ◽  
Umesh C. Karandikar ◽  
...  
Keyword(s):  
Hormone Secretion ◽  
Neurogenin 3 ◽  
Gut Hormone ◽  
Novel Model

scholarly journals CurvChip - chip platform for investigating cell responses to curved surface features

2018 ◽  
Vol 4 (1) ◽  
pp. 453-456
Author(s):  
Ralf Kemkemer ◽  
Kerstin Frey ◽  
Alena Fischer ◽  
Rumen Krastev
Keyword(s):  
Low Cost ◽  
Cell Types ◽  
Cell Responses ◽  
Surface Topographies ◽  
Sharp Edges ◽  
Pdms Molding ◽  
The Impact ◽  
Thermal Reflow

AbstractSurface topographies are often discussed as an important parameter influencing basic cell behavior. Whereas most in-vitro studies deal with microstructures with sharp edges, smooth, curved microscale topographies might be more relevant concerning in-vivo situations. Addressing the lack of highly defined surfaces with varying curvature, we present a topography chip system with 3D curved features of varying spacing, curvature radii as well as varying overall dimensions of curved surfaces. The CurvChip is produced by low-cost photolithography with thermal reflow, subsequent (repetitive) PDMS molding and hot embossing. The platform facilitates the systematic invitro investigation of the impact of substrate curvature on cell types like epithelial, endothelial, smooth muscle cells, or stem cells. Such investigations will not only help to further understand the mechanism of curvature sensation but may also contribute to optimize cellmaterial interactions in the field of regenerative medicine.

scholarly journals Impact of a High-fat Diet on Tissue Acyl-CoA and Histone Acetylation Levels

2017 ◽  
Vol 292 (8) ◽  
pp. 3312-3322 ◽  
Author(s):  
Alessandro Carrer ◽  
Joshua L. D. Parris ◽  
Sophie Trefely ◽  
Ryan A. Henry ◽  
David C. Montgomery ◽  
...  
Keyword(s):  
Histone Acetylation ◽  
High Fat Diet ◽  
Cell Types ◽  
High Fat ◽  
Atp Citrate Lyase ◽  
Acetyl Coa ◽  
Citrate Lyase ◽  
Liver And Pancreas ◽  
The Impact

Cellular metabolism dynamically regulates the epigenome via availability of the metabolite substrates of chromatin-modifying enzymes. The impact of diet on the metabolism-epigenome axis is poorly understood but could alter gene expression and influence metabolic health. ATP citrate-lyase produces acetyl-CoA in the nucleus and cytosol and regulates histone acetylation levels in many cell types. Consumption of a high-fat diet (HFD) results in suppression of ATP citrate-lyase levels in tissues such as adipose and liver, but the impact of diet on acetyl-CoA and histone acetylation in these tissues remains unknown. Here we examined the effects of HFD on levels of acyl-CoAs and histone acetylation in mouse white adipose tissue (WAT), liver, and pancreas. We report that mice consuming a HFD have reduced levels of acetyl-CoA and/or acetyl-CoA:CoA ratio in these tissues. In WAT and the pancreas, HFD also impacted the levels of histone acetylation; in particular, histone H3 lysine 23 acetylation was lower in HFD-fed mice. Genetic deletion of Acly in cultured adipocytes also suppressed acetyl-CoA and histone acetylation levels. In the liver, no significant effects on histone acetylation were observed with a HFD despite lower acetyl-CoA levels. Intriguingly, acetylation of several histone lysines correlated with the acetyl-CoA: (iso)butyryl-CoA ratio in liver. Butyryl-CoA and isobutyryl-CoA interacted with the acetyltransferase P300/CBP-associated factor (PCAF) in liver lysates and inhibited its activity in vitro. This study thus provides evidence that diet can impact tissue acyl-CoA and histone acetylation levels and that acetyl-CoA abundance correlates with acetylation of specific histone lysines in WAT but not in the liver.

scholarly journals Screening for GPR101 defects in pediatric pituitary corticotropinomas

2016 ◽  
Vol 23 (5) ◽  
pp. 357-365 ◽  
Author(s):  
Giampaolo Trivellin ◽  
Ricardo R Correa ◽  
Maria Batsis ◽  
Fabio R Faucz ◽  
Prashant Chittiboina ◽  
...  
Keyword(s):  
Adrenocorticotropic Hormone ◽  
Somatic Mutations ◽  
Hormone Secretion ◽  
Camp Signaling ◽  
Pituitary Hormone ◽  
Significant Percentage ◽  
Functional Studies ◽  
Acth Secreting ◽  
G Protein Coupled

Cushing’s disease (CD) in children is caused by adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. Germline or somatic mutations in genes such as MEN1, CDKIs, AIP, and USP8 have been identified in pediatric CD, but the genetic defects in a significant percentage of cases are still unknown. In this study, we investigated the orphan G-protein-coupled receptor GPR101, a gene known to be involved in somatotropinomas, for its possible involvement in corticotropinomas. We performed GPR101 sequencing, expression analyses by RT-qPCR and immunostaining, and functional studies (cell proliferation, pituitary hormone secretion, and cAMP measurement) in a series of patients with sporadic CD secondary to ACTH-secreting adenomas in whom we extracted DNA from peripheral blood and pituitary tumor samples (n=36). No increased GPR101 expression was observed in tumors compared with normal pituitary (NP) tissues, nor did we find a correlation between GPR101 and ACTH expression levels. Sequence analysis revealed a very rare germline heterozygous GPR101 variant (p.G31S) in one patient with CD. Overexpression of the p.G31S variant did not lead to increased growth and proliferation, although modest effects on cAMP signaling were observed. GPR101 is not overexpressed in ACTH-secreting tumors compared with NPs. In conclusion, rare germline GPR101 variant was found in one patient with CD, but in vitro studies did not support a consistent pathogenic effect. GPR101 is unlikely to be involved in the pathogenesis of CD.

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