scholarly journals Targeted delivery of antisense oligonucleotides to pancreatic β-cells

2018 ◽  
Vol 4 (10) ◽  
pp. eaat3386 ◽  
Author(s):  
C. Ämmälä ◽  
W. J. Drury ◽  
L. Knerr ◽  
I. Ahlstedt ◽  
P. Stillemark-Billton ◽  
...  

Antisense oligonucleotide (ASO) silencing of the expression of disease-associated genes is an attractive novel therapeutic approach, but treatments are limited by the ability to deliver ASOs to cells and tissues. Following systemic administration, ASOs preferentially accumulate in liver and kidney. Among the cell types refractory to ASO uptake is the pancreatic insulin-secreting β-cell. Here, we show that conjugation of ASOs to a ligand of the glucagon-like peptide-1 receptor (GLP1R) can productively deliver ASO cargo to pancreatic β-cells both in vitro and in vivo. Ligand-conjugated ASOs silenced target genes in pancreatic islets at doses that did not affect target gene expression in liver or other tissues, indicating enhanced tissue and cell type specificity. This finding has potential to broaden the use of ASO technology, opening up novel therapeutic opportunities, and presents an innovative approach for targeted delivery of ASOs to additional cell types.

2020 ◽  
Author(s):  
Yao Wang ◽  
Xinxing Lin ◽  
Jin Lv ◽  
Jiachen Zhu ◽  
Haowen Fan ◽  
...  

Abstract Background: iPSCs-derived β-like cell differentiation provides a novel strategy for type 1 diabetes treatment. Clarifying the regulatory mechanisms of lncRNAs in β-like cells derived from induced pluripotent stem cells (iPSCs) is not only significant for understanding the development of pancreas or pancreatic β cells, but also helpful for improving the quality of β-like cells for stem cell therapy.Methods: β-like cells derived from iPSCs followed a three-step protocol. RNA-sequencing was carried out to screen the differentially expressed lncRNAs which was probably involved in the differentiation of pancreatic β cells. Bioinformatics was performed to analyze the putative target genes of significantly differentially expressed lncRNAs. LncRNA Malat1 was chosen for further research. Lentivirus victor, siRNA victor, antagomir victor and mimic victor were constructed for overexpression of lncRNA Malat1, knockdown of lncRNA Malat1, knockdown of miR-15b-5p and overexpression of miR-15b-5p respectively. Quantitative Real-Time PCR (qRT-PCR), Western Blot and Immunofluorescence (IF) staining were carried out to detect the functions of pancreatic β cells at mRNA and protein level separately. Cytoplasmic and nuclear RNA fractionation and Fluorescence in situ hybridization (FISH) were to ventilate the subcellar location of lncRNA Malat1 in β-like cells. Flow cytometry and ELISA were performed to examine differentiation efficiency and function of insulin secretion from β-like cells after being stimulated with different concentrations of glucose. Structural interactions between lncRNA Malat1 and miR-15b-5p and between miR-15b-5p and Ihh were detected by Dual luciferase reporter assay (LRA).Results: We found that expression of lncRNA Malat1 was on the decline during the differentiation and overexpression of this lncRNA obviously impaired the differentiation and maturation of β-like cells derived from iPSCs in vitro and in vivo. Localized to the cytoplasm, lncRNA Malat1 could function as a competing endogenous RNA (ceRNA) of miR-15b-5p to regulate the expression of Ihh according the bioinformatic prediction, mechanistic analysis and downstream experiments.Conclusion: This study built an unreported regulatory network of lncRNA Malat1 and miR-15b-5p/Ihh axis during differentiation of iPSCs into β-like cells. Except for acting as a proverbial oncogene promoting tumorigenesis, lncRNA Malat1 may provide effective and novel molecule for diabetes cell therapy in the future.


2021 ◽  
Author(s):  
Yao Wang ◽  
Xinxing Lin ◽  
Jin Lv ◽  
Jiachen Zhu ◽  
Haowen Fan ◽  
...  

Abstract Background: Differentiation of induced pluripotent stem cell (iPSC)-derived β-like cells is a novel strategy for treatment of type 1 diabetes. Elucidation of the regulatory mechanisms of long noncoding RNAs (lncRNAs) in β-like cells derived from iPSCs is important for understanding the development of the pancreas and pancreatic β-cells and may improve the quality of β-like cells for stem cell therapy.Methods: β-like cells were derived from iPSCs in a three-step protocol. RNA sequencing and bioinformatics analysis were carried out to screen the differentially expressed lncRNAs and identify the putative target genes separately. LncRNA Malat1 was chosen for further research. Series of loss and gain of functions experiments were performed to study the biological function of this lncRNA. Quantitative real-time PCR (qRT-PCR), Western blot analysis and immunofluorescence (IF) staining were carried out to separately detect the functions of pancreatic β-cells at the mRNA and protein levels. Cytoplasmic and nuclear RNA fractionation and fluorescence in situ hybridization (FISH) were used to determine the subcellar location of lncRNA Malat1 in β-like cells. Flow cytometry and enzyme-linked immunosorbent assays (ELISAs) were performed to examine the differentiation and insulin secretion of β-like cells after stimulation with different glucose concentrations. Structural interactions between lncRNA Malat1 and miR-15b-5p and between miR-15b-5p and Ihh were detected by dual luciferase reporter assays (LRAs).Results: We found that the expression of lncRNA Malat1 declined during differentiation, and overexpression of this lncRNA notably impaired the differentiation and maturation of β-like cells derived from iPSCs in vitro and in vivo. Localized to the cytoplasm, lncRNA Malat1 could function as a competing endogenous RNA (ceRNA) of miR-15b-5p to regulate the expression of Ihh according to bioinformatics prediction, mechanistic analysis and downstream experiments.Conclusion: This study established an unreported regulatory network of lncRNA Malat1 and the miR-15b-5p/Ihh axis during the differentiation of iPSCs into β-like cells. In addition to acting as an oncogene promoting tumorigenesis, lncRNA Malat1 may be an effective and novel target for treatment of diabetes in the future.


2021 ◽  
Vol 165 ◽  
pp. 44
Author(s):  
Eleonora Cremonini ◽  
Maëlys Rouget ◽  
Solenne Arredi ◽  
Charlotte Devulder-Mercier ◽  
Robin Cellier ◽  
...  

RMD Open ◽  
2018 ◽  
Vol 4 (2) ◽  
pp. e000744 ◽  
Author(s):  
Kerstin Klein

The reading of acetylation marks on histones by bromodomain (BRD) proteins is a key event in transcriptional activation. Small molecule inhibitors targeting bromodomain and extra-terminal (BET) proteins compete for binding to acetylated histones. They have strong anti-inflammatory properties and exhibit encouraging effects in different cell types in vitro and in animal models resembling rheumatic diseases in vivo. Furthermore, recent studies that focus on BRD proteins beyond BET family members are discussed.


2019 ◽  
Vol 9 ◽  
Author(s):  
Rashmi Rajappa ◽  
Dornadula Sireesh ◽  
Magesh B. Salai ◽  
Kunka M. Ramkumar ◽  
Suryanarayanan Sarvajayakesavulu ◽  
...  

2020 ◽  
Vol 21 (13) ◽  
pp. 4668
Author(s):  
Rebecca Scheuer ◽  
Stephan Ernst Philipp ◽  
Alexander Becker ◽  
Lisa Nalbach ◽  
Emmanuel Ampofo ◽  
...  

The regulation of insulin biosynthesis and secretion in pancreatic β-cells is essential for glucose homeostasis in humans. Previous findings point to the highly conserved, ubiquitously expressed serine/threonine kinase CK2 as having a negative regulatory impact on this regulation. In the cell culture model of rat pancreatic β-cells INS-1, insulin secretion is enhanced after CK2 inhibition. This enhancement is preceded by a rise in the cytosolic Ca2+ concentration. Here, we identified the serine residues S2362 and S2364 of the voltage-dependent calcium channel CaV2.1 as targets of CK2 phosphorylation. Furthermore, co-immunoprecipitation experiments revealed that CaV2.1 binds to CK2 in vitro and in vivo. CaV2.1 knockdown experiments showed that the increase in the intracellular Ca2+ concentration, followed by an enhanced insulin secretion upon CK2 inhibition, is due to a Ca2+ influx through CaV2.1 channels. In summary, our results point to a modulating role of CK2 in the CaV2.1-mediated exocytosis of insulin.


2017 ◽  
Vol 448 ◽  
pp. 108-121 ◽  
Author(s):  
Lukas A. Berchtold ◽  
Michela Miani ◽  
Thi A. Diep ◽  
Andreas N. Madsen ◽  
Valentina Cigliola ◽  
...  

2020 ◽  
Author(s):  
Andrew Tae-Jun Kwon ◽  
Kohta Mohri ◽  
Satoshi Takizawa ◽  
Takahiro Arakawa ◽  
Maiko Takahashi ◽  
...  

AbstractAntibody-drug conjugates offers many advantages as a drug delivery platform that allows for highly specific targeting of cell types and genes. Ideally, testing the efficacy of these systems requires two cell types to be different only in the gene targeted by the drug, with the rest of the cellular machinery unchanged, in order to minimize other potential differences from obscuring the effects of the drug. In this study, we created multiple variants of U87MG cells with targeted mutation in the TP53 gene using the CRISPR-Cas9 system, and determined that their major transcriptional differences stem from the loss of p53 function. Using the transcriptome data, we predicted which mutant clones would have less divergent phenotypes from the wild type and thereby serve as the best candidates to be used as drug delivery testing platforms. Further in vitro and in vivo assays of cell morphology, proliferation rate and target antigen-mediated uptake supported our predictions. Based on the combined analysis results, we successfully selected the best qualifying mutant clone. This study serves as proof-of-principle of the approach and paves the way for extending to additional cell types and target genes.


2019 ◽  
Author(s):  
Abhinav Choubey ◽  
Aditya K Kar ◽  
Khyati Girdhar ◽  
Tandrika Chattopadhyay ◽  
Surbhi Dogra ◽  
...  

SummaryInsulin resistance results from several pathophysiologic mechanisms, including chronic tissue inflammation and defective insulin signaling. Pancreatic β-cells hypersecretion (hyperinsulinemia), is a central hallmark of peripheral insulin resistance. However, the underlying mechanism by which hyperinsulinemia perpetuates towards the development of insulin resistance remains unclear and is still a bigger therapeutic challenge. Here, we found hyperinsulinemia triggers inflammation and insulin resistance by stimulating TLR4-driven inflammatory cascades. We show that hyperinsulinemia activates the TLR4 signaling through HMGB1, an endogenous TLR4 ligand emanating from hyperinsulinemia exposed immune cells and peripheral organs like adipose tissue and liver. Further, our observation suggests hyperinsulinemia ensuring hyperacetylation, nuclear-to-cytoplasmic shuttling and release of HMGB1 into the extracellular space. HMGB1 was also found to be elevated in serum of T2DM patients. We found that extracellular HMGB1 plays a crucial role to promote proinflammatory responses and provokes systemic insulin resistance. Importantly, in-vitro and in-vivo treatment with naltrexone, a TLR4 antagonist led to an anti-inflammatory phenotype with protection from hyperinsulinemia mediated insulin resistance. In-vitro treatment with naltrexone directly enhanced SIRT1 activity, blocked the release of HMGB1 into extracellular milieu, suppressed release of proinflammatory cytokines and ultimately led to insulin-sensitizing effects. These observations elucidate a regulatory network between pancreatic β-cells, macrophage and hepatocytes and assign an unexpected role of TLR4 - HMGB1 signaling axis in hyperinsulinemia mediated systemic insulin resistance.Graphical Abstract


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