scholarly journals In vivo reprogramming of pancreatic acinar cells to three islet endocrine subtypes

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Weida Li ◽  
Mio Nakanishi ◽  
Adrian Zumsteg ◽  
Matthew Shear ◽  
Christopher Wright ◽  
...  

Direct lineage conversion of adult cells is a promising approach for regenerative medicine. A major challenge of lineage conversion is to generate specific cell subtypes. The pancreatic islets contain three major hormone-secreting endocrine subtypes: insulin+ β-cells, glucagon+ α-cells, and somatostatin+ δ-cells. We previously reported that a combination of three transcription factors, Ngn3, Mafa, and Pdx1, directly reprograms pancreatic acinar cells to β-cells. We now show that acinar cells can be converted to δ-like and α-like cells by Ngn3 and Ngn3+Mafa respectively. Thus, three major islet endocrine subtypes can be derived by acinar reprogramming. Ngn3 promotes establishment of a generic endocrine state in acinar cells, and also promotes δ-specification in the absence of other factors. δ-specification is in turn suppressed by Mafa and Pdx1 during α- and β-cell induction. These studies identify a set of defined factors whose combinatorial actions reprogram acinar cells to distinct islet endocrine subtypes in vivo.

2021 ◽  
pp. 153537022110325
Author(s):  
Guang-Wen Li ◽  
Ji Li ◽  
Xiao-Yan Feng ◽  
Hui Chen ◽  
Ye Chen ◽  
...  

The pancreatic β cells can synthesize dopamine by taking L-dihydroxyphenylalanine, but whether pancreatic acinar cells synthesize dopamine has not been confirmed. By means of immunofluorescence, the tyrosine hydroxylase -immunoreactivity and aromatic amino acid decarboxylase (AADC)- immunoreactivity were respectively observed in pancreatic acinar cells and islet β cells. Treatment with L-dihydroxyphenylalanine, not tyrosine, caused the production of dopamine in the incubation of INS-1 cells (rat islet β cell line) and primary isolated islets, which was blocked by AADC inhibitor NSD-1015. However, only L-dihydroxyphenylalanine, but not dopamine, was detected when AR42J cells (rat pancreatic acinar cell line) were treated with tyrosine, which was blocked by tyrosine hydroxylase inhibitor AMPT. Dopamine was detected in the coculture of INS-1 cells with AR42J cells after treatment with tyrosine. In an in vivo study, pancreatic juice contained high levels of L-dihydroxyphenylalanine and dopamine. Both L-dihydroxyphenylalanine and dopamine accompanied with pancreatic enzymes and insulin in the pancreatic juice were all significantly increased after intraperitoneal injection of bethanechol chloride and their increases were all blocked by atropine. Inhibiting TH with AMPT blocked bethanechol chloride-induced increases in L-dihydroxyphenylalanine and dopamine, while inhibiting AADC with NSD-1015 only blocked the dopamine increase. Bilateral subdiaphragmatic vagotomy of rats leads to significant decreases of L-dihydroxyphenylalanine and dopamine in pancreatic juice. These results suggested that pancreatic acinar cells could utilize tyrosine to synthesize L-dihydroxyphenylalanine, not dopamine. Islet β cells only used L-dihydroxyphenylalanine, not tyrosine, to synthesize dopamine. Both L-dihydroxyphenylalanine and dopamine were respectively released into the pancreatic duct, which was regulated by the vagal cholinergic pathway. The present study provides important evidences for the source of L-dihydroxyphenylalanine and dopamine in the pancreas.


Endocrinology ◽  
2014 ◽  
Vol 155 (10) ◽  
pp. 3829-3842 ◽  
Author(s):  
Akari Inada ◽  
Oogi Inada ◽  
Nobuharu L. Fujii ◽  
Kei Fujishima ◽  
Tetsuichiro Inai ◽  
...  

Abstract Previously we have generated transgenic (Tg) mice developing severe diabetes early in life with a profound depletion of β-cells with β-cell-directed expression of inducible cAMP early repressor-Iγ. Only male mice continue to demonstrate hyperglycemia throughout life. To investigate this sexual dimorphism, we treated severely diabetic male Tg mice with orchiectomy (ORX) or 17β-estradiol (E2) pellet implantation alone or in combination with ORX and E2-implantation to change the circulating levels and patterns of the ratio of estradiol to androgens. In the Tg-ORX group, the blood-glucose levels decreased to a certain level within several weeks but never reached the female Tg-control level. In contrast, the Tg-ORX+E2 or Tg-E2 group showed a more rapid drop in blood glucose to the basal level with a substantial increase in β-cells, thus preventing the occurrence of severe diabetes in the male mice. The β-cells, not only within islet but also in and adjacent to ducts and scattered β-cell clusters, were strongly induced by 1 week after treatment, and the islet morphology dramatically changed. Enhanced β-cell induction in the ducts occurred concomitantly with markedly increased levels of pancreatic duodenal homeobox-1 and related transcription factors. The glucose-lowering and β-cell-increasing effects were independent of the age at which the treatment is started. These data provide evidence that the circulating level of E2 and the ratio of E2 to T greatly affect the blood glucose levels, the β-cell induction, and the islet morphology in diabetic male Tg mice. This novel mechanism offers great potential for developing strategies to increase the number of β-cells in vivo.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 264
Author(s):  
Seon-Heui Cha ◽  
Chunying Zhang ◽  
Soo-Jin Heo ◽  
Hee-Sook Jun

Pancreatic β-cell loss is critical in diabetes pathogenesis. Up to now, no effective treatment has become available for β-cell loss. A polyphenol recently isolated from Polysiphonia japonica, 5-Bromoprotocatechualdehyde (BPCA), is considered as a potential compound for the protection of β-cells. In this study, we examined palmitate (PA)-induced lipotoxicity in Ins-1 cells to test the protective effects of BPCA on insulin-secreting β-cells. Our results demonstrated that BPCA can protect β-cells from PA-induced lipotoxicity by reducing cellular damage, preventing reactive oxygen species (ROS) overproduction, and enhancing glucose-stimulated insulin secretion (GSIS). BPCA also improved mitochondrial morphology by preserving parkin protein expression. Moreover, BPCA exhibited a protective effect against PA-induced β-cell dysfunction in vivo in a zebrafish model. Our results provide strong evidence that BPCA could be a potential therapeutic agent for the management of diabetes.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Dror Sever ◽  
Anat Hershko-Moshe ◽  
Rohit Srivastava ◽  
Roy Eldor ◽  
Daniel Hibsher ◽  
...  

AbstractNF-κB is a well-characterized transcription factor, widely known for its roles in inflammation and immune responses, as well as in control of cell division and apoptosis. However, its function in β-cells is still being debated, as it appears to depend on the timing and kinetics of its activation. To elucidate the temporal role of NF-κB in vivo, we have generated two transgenic mouse models, the ToIβ and NOD/ToIβ mice, in which NF-κB activation is specifically and conditionally inhibited in β-cells. In this study, we present a novel function of the canonical NF-κB pathway during murine islet β-cell development. Interestingly, inhibiting the NF-κB pathway in β-cells during embryogenesis, but not after birth, in both ToIβ and NOD/ToIβ mice, increased β-cell turnover, ultimately resulting in a reduced β-cell mass. On the NOD background, this was associated with a marked increase in insulitis and diabetes incidence. While a robust nuclear immunoreactivity of the NF-κB p65-subunit was found in neonatal β-cells, significant activation was not detected in β-cells of either adult NOD/ToIβ mice or in the pancreata of recently diagnosed adult T1D patients. Moreover, in NOD/ToIβ mice, inhibiting NF-κB post-weaning had no effect on the development of diabetes or β-cell dysfunction. In conclusion, our data point to NF-κB as an important component of the physiological regulatory circuit that controls the balance of β-cell proliferation and apoptosis in the early developmental stages of insulin-producing cells, thus modulating β-cell mass and the development of diabetes in the mouse model of T1D.


2017 ◽  
Vol 233 (3) ◽  
pp. 217-227 ◽  
Author(s):  
Maaike M Roefs ◽  
Françoise Carlotti ◽  
Katherine Jones ◽  
Hannah Wills ◽  
Alexander Hamilton ◽  
...  

Type 2 diabetes (T2DM) is associated with pancreatic islet dysfunction. Loss of β-cell identity has been implicated via dedifferentiation or conversion to other pancreatic endocrine cell types. How these transitions contribute to the onset and progression of T2DM in vivo is unknown. The aims of this study were to determine the degree of epithelial-to-mesenchymal transition occurring in α and β cells in vivo and to relate this to diabetes-associated (patho)physiological conditions. The proportion of islet cells expressing the mesenchymal marker vimentin was determined by immunohistochemistry and quantitative morphometry in specimens of pancreas from human donors with T2DM (n = 28) and without diabetes (ND, n = 38) and in non-human primates at different stages of the diabetic syndrome: normoglycaemic (ND, n = 4), obese, hyperinsulinaemic (HI, n = 4) and hyperglycaemic (DM, n = 8). Vimentin co-localised more frequently with glucagon (α-cells) than with insulin (β-cells) in the human ND group (1.43% total α-cells, 0.98% total β-cells, median; P < 0.05); these proportions were higher in T2DM than ND (median 4.53% α-, 2.53% β-cells; P < 0.05). Vimentin-positive β-cells were not apoptotic, had reduced expression of Nkx6.1 and Pdx1, and were not associated with islet amyloidosis or with bihormonal expression (insulin + glucagon). In non-human primates, vimentin-positive β-cell proportion was larger in the diabetic than the ND group (6.85 vs 0.50%, medians respectively, P < 0.05), but was similar in ND and HI groups. In conclusion, islet cell expression of vimentin indicates a degree of plasticity and dedifferentiation with potential loss of cellular identity in diabetes. This could contribute to α- and β-cell dysfunction in T2DM.


Endocrinology ◽  
2009 ◽  
Vol 150 (9) ◽  
pp. 4074-4083 ◽  
Author(s):  
Ji-Won Kim ◽  
Young-Hye You ◽  
Dong-Sik Ham ◽  
Jae-Hyoung Cho ◽  
Seung-Hyun Ko ◽  
...  

Abstract Peroxisome proliferator-activated receptor γ-coactivator-1α (PGC-1α) is significantly elevated in the islets of animal models of diabetes. However, the molecular mechanism has not been clarified. We investigated whether the suppression of PGC-1α expression protects against β-cell dysfunction in vivo and determined the mechanism of action of PGC-1α in β-cells. The studies were performed in glucolipotixicity-induced primary rat islets and INS-1 cells. In vitro and in vivo approaches using adenoviruses were used to evaluate the role of PGC-1α in glucolipotoxicity-associated β-cell dysfunction. The expression of PGC-1α in cultured β-cells increased gradually with glucolipotoxicity. The overexpression of PGC-1α also suppressed the expression of the insulin and β-cell E-box transcription factor (BETA2/NeuroD) genes, which was reversed by PGC-1α small interfering RNA (siRNA). BETA2/NeuroD, p300-enhanced BETA2/NeuroD, and insulin transcriptional activities were significantly suppressed by Ad-PGC-1α but were rescued by Ad-siPGC-1α. PGC-1α binding at the glucocorticoid receptor site on the BETA2/NeuroD promoter increased in the presence of PGC-1α. Ad-siPGC-1α injection through the celiac arteries of 90% pancreatectomized diabetic rats improved their glucose tolerance and maintained their fasting insulin levels. The suppression of PGC-1α expression protects the glucolipotoxicity-induced β-cell dysfunction in vivo and in vitro. A better understanding of the functions of molecules such as PGC-1α, which play key roles in intracellular fuel regulation, could herald a new era of the treatment of patients with type 2 diabetes mellitus by providing protection from glucolipotoxicity, which is an important cause of the development and progression of the disease.


2018 ◽  
Vol 103 (6) ◽  
pp. 2126-2135 ◽  
Author(s):  
Abu Saleh Md Moin ◽  
Megan Cory ◽  
Jennifer Choi ◽  
Allison Ong ◽  
Sangeeta Dhawan ◽  
...  

Abstract Context Chronic pancreatitis (CP) is characterized by inflammation, fibrosis, and a loss of pancreatic acinar cells, which can result in exocrine and eventually endocrine deficiency. Pancreatitis has been reported to induce formation of new endocrine cells (neogenesis) in mice. Our recent data have implicated chromogranin A–positive hormone-negative (CPHN) cells as potential evidence of neogenesis in humans. Objective We sought to establish if CPHN cells were more abundant in CP in humans. Design, Setting, and Participants We investigated the frequency and distribution of CPHN cells and the expression of the chemokine C-X-C motif ligand 10 (CXCL10) and its receptor chemokine C-X-C motif receptor 3 in pancreas of nondiabetic subjects with CP. Results CPHN cell frequency in islets was increased sevenfold in CP [2.1% ± 0.67% vs 0.35% ± 0.09% CPHN cells in islets, CP vs nonpancreatitis (NP), P &lt; 0.01], as were the CPHN cells found as scattered cells in the exocrine areas (17.4 ± 2.9 vs 4.2 ± 0.6, CP vs NP, P &lt; 0.001). Polyhormonal endocrine cells were also increased in CP (2.7 ± 1.2 vs 0.1 ± 0.04, CP vs NP, % of polyhormonal cells of total endocrine cells, P &lt; 0.01), as was expression of CXCL10 in α and β cells. Conclusion There is increased islet endogenous expression of the inflammation marker CXCL10 in islets in the setting of nondiabetic CP and an increase in polyhormonal (insulin-glucagon expressing) cells. The increase in CPHN cells in CP, often in a lobular distribution, may indicate foci of attempted endocrine cell regeneration.


2020 ◽  
Vol 49 (15) ◽  
pp. 4732-4740 ◽  
Author(s):  
Thomas J. Clough ◽  
Nicoleta Baxan ◽  
Emma J. Coakley ◽  
Charlotte Rivas ◽  
Lan Zhao ◽  
...  

A novel probe based on an exendin-4-dota(ga) conjugate, GdEx, is presented. GdEx accumulates in the pancreas, allowing organ-specific contrast enhancement which is reduced in mouse models where pancreatic β-cells are depleted.


2008 ◽  
Vol 36 (3) ◽  
pp. 334-339 ◽  
Author(s):  
Danielle Melloul

Apoptotic β-cell death appears to be central to the pathogenesis of Type 1 diabetes mellitus and in islet graft rejection. The β-cell destruction is partially mediated by cytokines, such as IL-1β (interleukin 1β), TNFα (tumour necrosis factor α) and IFN-γ (interferon γ). IL-1β and TNFα mediate activation of the transcription factor NF-κB (nuclear factor κB) pathway. Use of a degradation-resistant NF-κB protein inhibitor (ΔNIκBα), specifically expressed in β-cells, significantly reduced IL-1β+IFN-γ-induced apoptosis. Moreover, in vivo, it protected against multiple low-dose streptozocin-induced diabetes, with reduced intra-islet lymphocytic infiltration. Thus β-cell-specific activation of NF-κB is a key event in the progressive loss of β-cells in diabetes. Inhibition of this process could be a potential effective strategy for β-cell protection.


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