scholarly journals Cholecystokinin Suppresses β-Cell Apoptosis, Including in Human Islets in a Transplant Model

2021 ◽  
Author(s):  
Hung Tae Kim ◽  
Arnaldo H. de Souza ◽  
Heidi Umhoefer ◽  
JeeYoung Han ◽  
Lucille Anzia ◽  
...  

AbstractLoss of functional pancreatic β-cell mass and increased β-cell apoptosis are fundamental to the pathophysiology of both type 1 and type 2 diabetes. Pancreatic islet transplantation has the potential to cure type 1 diabetes but is often ineffective due to the death of the islet graft within the first few years after transplant. Therapeutic strategies to directly target pancreatic β-cell survival are needed to prevent and treat diabetes and to improve islet transplant outcomes. Reducing β-cell apoptosis is also a therapeutic strategy for type 2 diabetes. Cholecystokinin (CCK) is a peptide hormone typically produced in the gut after food intake, with positive effects on obesity and glucose metabolism in mouse models and human subjects. We have previously shown that pancreatic islets also produce CCK. The production of CCK within the islet promotes β-cell survival in rodent models of diabetes and aging. Now, we demonstrate a direct effect of CCK to reduce cytokine-mediated apoptosis in a β-cell line and in isolated mouse islets in a receptor-dependent manner. However, whether CCK can protect human β-cells was previously unknown. Here, we report that CCK can also reduce cytokine-mediated apoptosis in isolated human islets and CCK treatment in vivo decreases β-cell apoptosis in human islets transplanted into the kidney capsule of diabetic NOD/SCID mice. Collectively, these data identify CCK as a novel therapy that can directly promote β-cell survival in human islets and has therapeutic potential to preserve β-cell mass in diabetes and as an adjunct therapy after transplant.One Sentence SummaryCholecystokinin ameliorates pancreatic β-cell death under models of stress and after transplant of human islets.

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ting Yuan ◽  
Karthika Annamalai ◽  
Shruti Naik ◽  
Blaz Lupse ◽  
Shirin Geravandi ◽  
...  

AbstractDiabetes results from a decline in functional pancreatic β-cells, but the molecular mechanisms underlying the pathological β-cell failure are poorly understood. Here we report that large-tumor suppressor 2 (LATS2), a core component of the Hippo signaling pathway, is activated under diabetic conditions and induces β-cell apoptosis and impaired function. LATS2 deficiency in β-cells and primary isolated human islets as well as β-cell specific LATS2 ablation in mice improves β-cell viability, insulin secretion and β-cell mass and ameliorates diabetes development. LATS2 activates mechanistic target of rapamycin complex 1 (mTORC1), a physiological suppressor of autophagy, in β-cells and genetic and pharmacological inhibition of mTORC1 counteracts the pro-apoptotic action of activated LATS2. We further show a direct interplay between Hippo and autophagy, in which LATS2 is an autophagy substrate. On the other hand, LATS2 regulates β-cell apoptosis triggered by impaired autophagy suggesting an existence of a stress-sensitive multicomponent cellular loop coordinating β-cell compensation and survival. Our data reveal an important role for LATS2 in pancreatic β-cell turnover and suggest LATS2 as a potential therapeutic target to improve pancreatic β-cell survival and function in diabetes.


Physiology ◽  
2009 ◽  
Vol 24 (6) ◽  
pp. 325-331 ◽  
Author(s):  
Marc Y. Donath ◽  
Marianne Böni-Schnetzler ◽  
Helga Ellingsgaard ◽  
Jan A. Ehses

Onset of Type 2 diabetes occurs when the pancreatic β-cell fails to adapt to the increased insulin demand caused by insulin resistance. Morphological and therapeutic intervention studies have uncovered an inflammatory process in islets of patients with Type 2 diabetes characterized by the presence of cytokines, immune cells, β-cell apoptosis, amyloid deposits, and fibrosis. This insulitis is due to a pathological activation of the innate immune system by metabolic stress and governed by IL-1 signaling. We propose that this insulitis contributes to the decrease in β-cell mass and the impaired insulin secretion observed in patients with Type 2 diabetes.


Endocrinology ◽  
2017 ◽  
Vol 158 (11) ◽  
pp. 3900-3913 ◽  
Author(s):  
Xiao-Ting Huang ◽  
Shao-Jie Yue ◽  
Chen Li ◽  
Yan-Hong Huang ◽  
Qing-Mei Cheng ◽  
...  

Abstract Type 2 diabetes, which features β-cell failure, is caused by the decrease of β-cell mass and insulin secretory function. Current treatments fail to halt the decrease of functional β-cell mass. Strategies to prevent β-cell apoptosis and dysfunction are highly desirable. Recently, our group and others have reported that blockade of N-methyl-d-aspartate receptors (NMDARs) in the islets has been proposed to prevent the progress of type 2 diabetes through improving β-cell function. It suggests that a sustained activation of the NMDARs may exhibit deleterious effect on β-cells. However, the exact functional impact and mechanism of the sustained NMDAR stimulation on islet β-cells remains unclear. Here, we identify a sustained activation of pancreatic NMDARs as a novel factor of apoptotic β-cell death and function. The sustained treatment with NMDA results in an increase of intracellular [Ca2+] and reactive oxygen species, subsequently induces mitochondrial membrane potential depolarization and a decrease of oxidative phosphorylation expression, and then impairs the mitochondrial function of β-cells. NMDA specifically induces the mitochondrial-dependent pathway of apoptosis in β-cells through upregulation of the proapoptotic Bim and Bax, and downregulation of antiapoptotic Bcl-2. Furthermore, a sustained stimulation of NMDARs impairs β-cell insulin secretion through decrease of pancreatic duodenal homeobox-1 (Pdx-1) and adenosine triphosphate synthesis. The activation of nuclear factor–κB partly contributes to the reduction of Pdx-1 expression induced by overstimulation of NMDARs. In conclusion, we show that the sustained stimulation of NMDARs is a novel mediator of apoptotic signaling and β-cell dysfunction, providing a mechanistic insight into the pathological role of NMDARs activation in diabetes.


2008 ◽  
Vol 8 (2_suppl) ◽  
pp. S19-S25 ◽  
Author(s):  
Baptist Gallwitz

The clinical course of type 2 diabetes mellitus is characterised by a progressive decline in β -cell mass. The changing β-cell mass reflects a shifting balance between β-cell neogenesis, islet neogenesis and β-cell apoptosis. In persons with diabetes, administration of exogenous glucagon-like peptide-1 (GLP-1) improves glucose sensitivity and insulin synthesis and may help increase β cell mass. As the effects of GLP-1 on the β cell are becoming better understood at both the molecular and cellular levels, it has become possible to develop therapies with the potential to harness and sustain the positive effects of endogenous GLP-1 in patients with type 2 diabetes. Data from in vitro, preclinical and phase II studies show promising results with GLP-1 analogues in improving β-cell function in patients with type 2 diabetes. For example, in vitro models have shown the GLP-1 analogue liraglutide inhibits β-cell apoptosis in isolated neonatal rat islets. In vitro, animal models demonstrate increasing β-cell mass with liraglutide administration. Results from a recently completed phase II clinical trial with liraglutide in patients with type 2 diabetes demonstrate that daily treatment markedly improves β -cell function as shown by an increased first-phase insulin response and secretory capacity and a decreased proinsulin:insulin ratio. Now, phase III trials continue to bear out the potential for liraglutide for treatment of patients with type 2 diabetes.Br J Diabetes Vasc Dis 2008;8 (Suppl 2): S19-S25


2021 ◽  
Author(s):  
Chieh-Hsin Yang ◽  
Danise Ann-Onda ◽  
Xuzhu Lin ◽  
Stacey Fynch ◽  
Shaktypreya Nadarajah ◽  
...  

Loss of functional β-cell mass is a key factor contributing to the poor glycaemic control in type 2 diabetes. However, therapies that directly target these underlying processes remains lacking. Here we demonstrate that gene expression of neuropeptide Y1 receptor and its ligand, neuropeptide Y, was significantly upregulated in human islets from subjects with type 2 diabetes. Importantly, the reduced insulin secretion in type 2 diabetes was associated with increased neuropeptide Y and Y1 receptor expression in human islets. Consistently, pharmacological inhibition of Y1 receptors by BIBO3304 significantly protected β-cells from dysfunction and death under multiple diabetogenic conditions in islets. In a preclinical study, Y1 receptor antagonist BIBO3304 treatment improved β-cell function and preserved functional β-cell mass, thereby resulting in better glycaemic control in both high-fat-diet/multiple low dose streptozotocin- and db/db type 2 diabetic mice. Collectively, our results uncovered a novel causal link of increased islet NPY-Y1 receptor signaling to β-cell dysfunction and failure in human type 2 diabetes. These results further demonstrate that inhibition of Y1 receptor by BIBO3304 represents a novel and effective β-cell protective therapy for improving functional β-cell mass and glycaemic control in type 2 diabetes.


2014 ◽  
Vol 5 (3) ◽  
pp. 278-288 ◽  
Author(s):  
Amelia K. Linnemann ◽  
Mieke Baan ◽  
Dawn Belt Davis

Abstract Because obesity rates have increased dramatically over the past 3 decades, type 2 diabetes has become increasingly prevalent as well. Type 2 diabetes is associated with decreased pancreatic β-cell mass and function, resulting in inadequate insulin production. Conversely, in nondiabetic obesity, an expansion in β-cell mass occurs to provide sufficient insulin and to prevent hyperglycemia. This expansion is at least in part due to β-cell proliferation. This review focuses on the mechanisms regulating obesity-induced β-cell proliferation in humans and mice. Many factors have potential roles in the regulation of obesity-driven β-cell proliferation, including nutrients, insulin, incretins, hepatocyte growth factor, and recently identified liver-derived secreted factors. Much is still unknown about the regulation of β-cell replication, especially in humans. The extracellular signals that activate proliferative pathways in obesity, the relative importance of each of these pathways, and the extent of cross-talk between these pathways are important areas of future study.


2018 ◽  
Vol 10 (3) ◽  
pp. 577-590 ◽  
Author(s):  
Ayumi Kanno ◽  
Shun‐ichiro Asahara ◽  
Mao Kawamura ◽  
Ayuko Furubayashi ◽  
Shoko Tsuchiya ◽  
...  

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Patlada Suthamwong ◽  
Manabu Minami ◽  
Toshiaki Okada ◽  
Nonomi Shiwaku ◽  
Mai Uesugi ◽  
...  

2016 ◽  
Vol 30 (4) ◽  
pp. 446-454 ◽  
Author(s):  
T. Gurlo ◽  
J. F. Rivera ◽  
A. E. Butler ◽  
M. Cory ◽  
J. Hoang ◽  
...  

The islet in type 2 diabetes is characterized by β-cell loss, increased β-cell apoptosis, and islet amyloid derived from islet amyloid polypeptide (IAPP). When protein misfolding protective mechanisms are overcome, human IAPP (h-IAPP) forms membrane permeant toxic oligomers that induce β-cell dysfunction and apoptosis. In humans with type 2 diabetes (T2D) and mice transgenic for h-IAPP, endoplasmic reticulum (ER) stress has been inferred from nuclear translocation of CCAAT/enhancer-binding protein homologous protein (CHOP), an established mediator of ER stress. To establish whether h-IAPP toxicity is mediated by ER stress, we evaluated diabetes onset and β-cell mass in h-IAPP transgenic (h-TG) mice with and without deletion of CHOP in comparison with wild-type controls. Diabetes was delayed in h-TG CHOP−/− mice, with relatively preserved β-cell mass and decreased β-cell apoptosis. Deletion of CHOP attenuates dysfunction of the autophagy/lysosomal pathway in β-cells of h-TG mice, uncovering a role for CHOP in mediating h-IAPP-induced dysfunction of autophagy. As deletion of CHOP delayed but did not prevent h-IAPP-induced β-cell loss and diabetes, we examined CHOP-independent stress pathways. JNK, a target of the IRE-1pTRAF2 complex, and the Bcl-2 family proapoptotic mediator BIM, a target of ATF4, were comparably activated by h-IAPP expression in the presence and absence of CHOP. Therefore, although these studies affirm that CHOP is a mediator of h-IAPP-induced ER stress, it is not the only one. Therefore, suppression of CHOP alone is unlikely to be a durable therapeutic strategy to protect against h-IAPP toxicity because multiple stress pathways are activated.


2004 ◽  
Vol 24 (13) ◽  
pp. 5721-5732 ◽  
Author(s):  
Matthew G. Hartman ◽  
Dan Lu ◽  
Mi-Lyang Kim ◽  
Gary J. Kociba ◽  
Tala Shukri ◽  
...  

ABSTRACT Activating transcription factor 3 (ATF3) is a stress-inducible gene and encodes a member of the ATF/CREB family of transcription factors. However, the physiological significance of ATF3 induction by stress signals is not clear. In this report, we describe several lines of evidence supporting a role of ATF3 in stress-induced β-cell apoptosis. First, ATF3 is induced in β cells by signals relevant to β-cell destruction: proinflammatory cytokines, nitric oxide, and high concentrations of glucose and palmitate. Second, induction of ATF3 is mediated in part by the NF-κB and Jun N-terminal kinase/stress-activated protein kinase signaling pathways, two stress-induced pathways implicated in both type 1 and type 2 diabetes. Third, transgenic mice expressing ATF3 in β cells develop abnormal islets and defects secondary to β-cell deficiency. Fourth, ATF3 knockout islets are partially protected from cytokine- or nitric oxide-induced apoptosis. Fifth, ATF3 is expressed in the islets of patients with type 1 or type 2 diabetes, and in the islets of nonobese diabetic mice that have developed insulitis or diabetes. Taken together, our results suggest ATF3 to be a novel regulator of stress-induced β-cell apoptosis.


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