ObjectiveThe generation of acinar and ductal cells from human pluripotent stem cells (PSCs) is a poorly studied process, although various diseases arise from this compartment.DesignWe designed a straightforward approach to direct human PSCs towards pancreatic organoids resembling acinar and ductal progeny.ResultsExtensive phenotyping of the organoids not only shows the appropriate marker profile but also ultrastructural, global gene expression and functional hallmarks of the human pancreas in the dish. Upon orthotopic transplantation into immunodeficient mice, these organoids form normal pancreatic ducts and acinar tissue resembling fetal human pancreas without evidence of tumour formation or transformation. Finally, we implemented this unique phenotyping tool as a model to study the pancreatic facets of cystic fibrosis (CF). For the first time, we provide evidence that in vitro, but also in our xenograft transplantation assay, pancreatic commitment occurs generally unhindered in CF. Importantly, cystic fibrosis transmembrane conductance regulator (CFTR) activation in mutated pancreatic organoids not only mirrors the CF phenotype in functional assays but also at a global expression level. We also conducted a scalable proof-of-concept screen in CF pancreatic organoids using a set of CFTR correctors and activators, and established an mRNA-mediated gene therapy approach in CF organoids.ConclusionsTaken together, our platform provides novel opportunities to model pancreatic disease and development, screen for disease-rescuing agents and to test therapeutic procedures.
Urocortin 2 (Ucn2) is a cardioactive peptide exhibiting beneficial effects in normal and failing heart. In cardiomyocytes, it elicits cAMP- and Ca(2+)-dependent positive inotropic and lusitropic effects. We tested the hypothesis that, in addition, Ucn2 activates cardiac nitric oxide (NO) signaling and elucidated the underlying signaling pathways and mechanisms. In isolated rabbit ventricular myocytes, Ucn2 caused concentration- and time-dependent increases in phosphorylation of Akt (Ser473, Thr308), endothelial NO synthase (eNOS) (Ser1177), and ERK1/2 (Thr202/Tyr204). ERK1/2 phosphorylation, but not Akt and eNOS phosphorylation, was suppressed by inhibition of MEK1/2. Increased Akt phosphorylation resulted in increased Akt kinase activity and was mediated by corticotropin-releasing factor 2 (CRF2) receptors (astressin-2B sensitive). Inhibition of phosphatidylinositol 3-kinase (PI3K) diminished both Akt as well as eNOS phosphorylation mediated by Ucn2. Inhibition of protein kinase A (PKA) reduced Ucn2-induced phosphorylation of eNOS but did not affect the increase in phosphorylation of Akt. Conversely, direct receptor-independent elevation of cAMP via forskolin increased phosphorylation of eNOS but not of Akt. Ucn2 increased intracellular NO concentration ([NO]i), [cGMP], [cAMP], and cell shortening. Inhibition of eNOS suppressed the increases in [NO]i and cell shortening. When both PI3K-Akt and cAMP-PKA signaling were inhibited, the Ucn2-induced increases in [NO]i and cell shortening were attenuated. Thus, in rabbit ventricular myocytes, Ucn2 causes activation of cAMP-PKA, PI3K-Akt, and MEK1/2-ERK1/2 signaling. The MEK1/2-ERK1/2 pathway is not required for stimulation of NO signaling in these cells. The other two pathways, cAMP-PKA and PI3K-Akt, converge on eNOS phosphorylation at Ser1177 and result in pronounced and sustained cellular NO production with subsequent stimulation of cGMP signaling.
Human pluripotent stem cells represent a powerful tool to study human embryonic development and disease but also open up novel strategies for cell replacement therapies. Their capacity to give rise to every cell type of the human body, meanwhile, enables researchers to generate high yields of mesodermal, ectodermal, but also endodermal-derived tissues such as hepatic, pancreatic, or intestinal cells. Another progress in the field came with the advent of 3-dimensional culture conditions, so-called organoids, which facilitate maturation of stem cells and in turn more faithfully recapitulate human tissue architecture. While several studies reported the derivation of organoid cultures from adult intestinal tissue, the derivation of intestinal organoids derived from plucked human hair of Crohn's disease patients has not been reported. The current research project reports such successful generation and characterization of induced pluripotent stem cells (iPSCs) derived from hair sheet keratinocyte cultures of a patient with Crohn's disease. Stepwise differentiation along the intestinal lineage showed no differences in intermediate stages such as definitive endoderm formation. We also directed the patterned primitive gut tube toward intestinal organoids resembling the cellular architecture of human "miniguts". As expected from current pathophysiological knowledge on Crohn's disease, there were no obvious morphological differences in the "miniguts" derived from healthy control and diseased patient-induced pluripotent stem cells. Taken together, our platform will enable for detailed and complementary phenotyping of the pathophysiology of Crohn's disease in a novel disease-in-a-dish format.
Objective To assess the effectiveness of oral spironolactone for acne vulgaris in adult women. Design Pragmatic, multicentre, phase 3, double blind, randomised controlled trial. Setting Primary and secondary healthcare, and advertising in the community and on social media in England and Wales. Participants Women (≥18 years) with facial acne for at least six months, judged to warrant oral antibiotics. Interventions Participants were randomly assigned (1:1) to either 50 mg/day spironolactone or matched placebo until week six, increasing to 100 mg/day spironolactone or placebo until week 24. Participants could continue using topical treatment. Main outcome measures Primary outcome was Acne-Specific Quality of Life (Acne-QoL) symptom subscale score at week 12 (range 0-30, where higher scores reflect improved QoL). Secondary outcomes were Acne-QoL at week 24, participant self-assessed improvement; investigator’s global assessment (IGA) for treatment success; and adverse reactions. Results From 5 June 2019 to 31 August 2021, 1267 women were assessed for eligibility, 410 were randomly assigned to the intervention (n=201) or control group (n=209) and 342 were included in the primary analysis (n=176 in the intervention group and n=166 in the control group). Baseline mean age was 29.2 years (standard deviation 7.2), 28 (7%) of 389 were from ethnicities other than white, with 46% mild, 40% moderate, and 13% severe acne. Mean Acne-QoL symptom scores at baseline were 13.2 (standard deviation 4.9) and at week 12 were 19.2 (6.1) for spironolactone and 12.9 (4.5) and 17.8 (5.6) for placebo (difference favouring spironolactone 1.27 (95% confidence interval 0.07 to 2.46), adjusted for baseline variables). Scores at week 24 were 21.2 (5.9) for spironolactone and 17.4 (5.8) for placebo (difference 3.45 (95% confidence interval 2.16 to 4.75), adjusted). More participants in the spironolactone group reported acne improvement than in the placebo group: no significant difference was reported at week 12 (72% v 68%, odds ratio 1.16 (95% confidence interval 0.70 to 1.91)) but significant difference was noted at week 24 (82% v 63%, 2.72 (1.50 to 4.93)). Treatment success (IGA classified) at week 12 was 31 (19%) of 168 given spironolactone and nine (6%) of 160 given placebo (5.18 (2.18 to 12.28)). Adverse reactions were slightly more common in the spironolactone group with more headaches reported (20% v 12%; p=0.02). No serious adverse reactions were reported. Conclusions Spironolactone improved outcomes compared with placebo, with greater differences at week 24 than week 12. Spironolactone is a useful alternative to oral antibiotics for women with acne. Trial registration ISRCTN12892056
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