scholarly journals Pro-Inflammatory Cytokines Induce Insulin and Glucagon Double Positive Human Islet Cells That Are Resistant to Apoptosis

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 320
Author(s):  
Marta Tesi ◽  
Marco Bugliani ◽  
Gianmarco Ferri ◽  
Mara Suleiman ◽  
Carmela De Luca ◽  
...  

The presence of islet cells double positive for insulin and glucagon (Ins+/Glu+) has been described in the pancreas from both type 2 (T2D) and type 1 (T1D) diabetic subjects. We studied the role of pro-inflammatory cytokines on the occurrence, trajectory, and characteristics of Ins+/Glu+ cells in human pancreatic islets. Pancreas samples, isolated islets, and dispersed islet cells from 3 T1D and 11 non-diabetic (ND) multi-organ donors were studied by immunofluorescence, confocal microscopy, and/or electron microscopy. ND islet cells were exposed to interleukin-1β and interferon-γ for up to 120 h. In T1D islets, we confirmed an increased prevalence of Ins+/Glu+ cells. Cytokine-exposed islets showed a progressive increase of Ins+/Glu+ cells that represented around 50% of endocrine cells after 120h. Concomitantly, cells expressing insulin granules only decreased significantly over time, whereas those containing only glucagon granules remained stable. Interestingly, Ins+/Glu+ cells were less prone to cytokine-induced apoptosis than cells containing only insulin. Cytokine-exposed islets showed down-regulation of β-cell identity genes. In conclusion, pro-inflammatory cytokines induce Ins+/Glu+ cells in human islets, possibly due to a switch from a β- to a β-/α-cell phenotype. These Ins+/Glu+ cells appear to be resistant to cytokine-induced apoptosis.

Diabetes ◽  
2021 ◽  
pp. db200847
Author(s):  
Wenting Wu ◽  
Farooq Syed ◽  
Edward Simpson ◽  
Chih-Chun Lee ◽  
Jing Liu ◽  
...  

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Wei He ◽  
Ting Yuan ◽  
Kathrin Maedler

AbstractObesity is associated with inflammatory macrophages in insulin responsive tissues and the resulting inflammatory response is a major contributor to insulin resistance. In insulin-producing pancreatic islets, the intra-islet accumulation of macrophages is observed in patients of type 2 diabetes (T2D), but such has not been investigated in obese individuals. Here, we show that pro-inflammatory cytokines (IL-1β, IL-6, and TNF), anti-inflammatory cytokines (IL-10 and TGF-β) and macrophage polarization markers (CD11c, CD163, and NOS2) were expressed in isolated human islets from non-diabetic donors. Clodronate-mediated depletion of resident macrophages revealed expression of IL1B and IL10 mostly from macrophages, while IL6, TNF, and TGFB1 came largely from a non-macrophage origin in human islets. NOS2 expression came exclusively from non-macrophage cells in non-obese individuals, while it originated also from macrophages in obese donors. Macrophage marker expression of CD68, CD163, and ITGAX was unchanged in islets of non-obese control and obese cohorts. In contrast, IL1B and NOS2 were significantly increased in islets from obese, compared to non-obese individuals, implying a more inflammatory macrophage phenotype in islets in obesity. Our study shows elevated macrophage-associated inflammation in human islets in obesity, which could be an initiating factor to the pro-inflammatory intra-islet milieu and contribute to the higher susceptibility to T2D in obese individuals.


2005 ◽  
Vol 385 (3) ◽  
pp. 815-821 ◽  
Author(s):  
Stephen R. CLARK ◽  
Peter B. ANNING ◽  
Marcus J. COFFEY ◽  
Andrew G. ROBERTS ◽  
Lawrence J. MARNETT ◽  
...  

PGHS-2 (prostaglandin H synthase-2) is induced in mammalian cells by pro-inflammatory cytokines in tandem with iNOS [high-output (‘inducible’) nitric oxide synthase], and is co-localized with iNOS and nitrotyrosine in human atheroma macrophages. Herein, murine J774.2 macrophages incubated with lipopolysaccharide and interferon γ showed induction of PGHS-2 and generated NO using iNOS that could be completely depleted by 12(S)-HPETE [12(S)-hydroperoxyeicosatetraenoic acid; 2.4 μM] or hydrogen peroxide (500 μM) (0.42±0.084 and 0.38±0.02 nmol·min−1·106 cells−1 for HPETE and H2O2 respectively). COS-7 cells transiently transfected with human PGHS-2 also showed HPETE- or H2O2-dependent NO decay (0.44±0.016 and 0.20±0.04 nmol·min−1·106 cells−1 for 2.4 μM HPETE and 500 μM H2O2 respectively). Finally, purified PGHS-2 consumed NO in the presence of HPETE or H2O2 (168 and 140 μM·min−1·μM enzyme−1 for HPETE and H2O2 respectively), in a haem-dependent manner, with 20 nM enzyme consuming up to 4 μM NO. Km (app) values for NO and 15(S)-HPETE were 1.7±0.2 and 0.45±0.16 μM respectively. These data indicate that PGHS-2 catalytically consumes NO during peroxidase turnover and that pro-inflammatory cytokines simultaneously upregulate NO synthesis and degradation pathways in murine macrophages. Catalytic NO consumption by PGHS-2 represents a novel interaction between NO and PGHS-2 that may impact on the biological effects of NO in vascular signalling and inflammation.


2010 ◽  
Vol 206 (2) ◽  
pp. 183-193 ◽  
Author(s):  
José Edgar Nicoletti-Carvalho ◽  
Tatiane C Araújo Nogueira ◽  
Renata Gorjão ◽  
Carla Rodrigues Bromati ◽  
Tatiana S Yamanaka ◽  
...  

Unfolded protein response (UPR)-mediated pancreatic β-cell death has been described as a common mechanism by which palmitate (PA) and pro-inflammatory cytokines contribute to the development of diabetes. There are evidences that interleukin 6 (IL6) has a protective action against β-cell death induced by pro-inflammatory cytokines; the effects of IL6 on PA-induced apoptosis have not been investigated yet. In the present study, we have demonstrated that PA selectively disrupts IL6-induced RAC-alpha serine/threonine-protein kinase (AKT) activation without interfering with signal transducer and activator of transcription 3 phosphorylation in RINm5F cells. The inability of IL6 to activate AKT in the presence of PA correlated with an inefficient protection against PA-induced apoptosis. In contrast to PA, IL6 efficiently reduced apoptosis induced by pro-inflammatory cytokines. In addition, we have demonstrated that IL6 is unable to overcome PA-stimulated UPR, as assessed by activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP) expression, X-box binding protein-1 gene mRNA splicing, and pancreatic eukaryotic initiation factor-2α kinase phosphorylation, whereas no significant induction of UPR by pro-inflammatory cytokines was detected. This unconditional stimulation of UPR and apoptosis by PA was accompanied by the stimulation of CHOP and tribble3 (TRIB3) expression, irrespective of the presence of IL6. These findings suggest that IL6 is unable to protect pancreatic β-cells from PA-induced apoptosis because it does not repress UPR activation. In this way, CHOP and ATF4 might mediate PA-induced TRIB3 expression and, by extension, the suppression of IL6 activation of pro-survival kinase AKT.


Author(s):  
Н.А. Воронина ◽  
В.Г. Кучеряну ◽  
Л.А. Ветрилэ ◽  
В.В. Голоборщева ◽  
И.Г. Капица ◽  
...  

Целью данных исследований явилось изучение влияния гимантана (N-(2-адамантил)-гексаметиленимина гидрохлорида) на уровень провоспалительных цитокинов IL-1β, IL-6, интерферона-γ (ИФН-γ) и фактора некроза опухоли-α (ФНО-α) в нигрокаудатном комплексе мышей на ранней и поздней клинической фазе экспериментального паркинсонического синдрома (ПС), для выяснения его антипаркинсонического эффекта. Методы исследования: Раннюю и позднюю клиническую фазу ПС создавали у мышей линии C57BL/6J внутрибрюшинным введением пронейротоксина 1-метил-4-фенил-1,2,3,6-тетрагидропиридина (МФТП) в дозах 12 мг/кг или 20 мг/кг по 4 инъекции с интервалом 2 часа, соответственно. Гимантан вводили мышам внутрибрюшинным в дозе 20 мг/кг, предварительно каждый раз за 30 мин до введения МФТП. Содержание цитокинов в структурах мозга мышей определяли методом иммуноферментного анализа с использованием тест-систем производства «Cloud-Clone Corporation», США и считывающего устройства «ИФА-reader» прибора «ImmunoChem-2100», США. Результаты: Показано, что уровень IL-1β, IL-6, ИФН-γ и ФНО-α в нигрокаудатном комплексе мозга мышей возрастает как на ранней, так и на поздней фазах развития ПС. Предварительное применение гимантана снижало в нигрокаудатном комплексе мышей содержание цитокинов IL-1β, ИФН-γ и ФНО-α на ранней фазе, и только одного из 4 изученных (IL-6) - на поздней фазе развития ПС. Предполагается, что антипаркинсонический эффект гимантана на ранней клинической стадии МФТП-индуцированного ПС осуществляется, в том числе, за счёт снижения уровня провоспалительных цитокинов в нигростриатной системе, предупреждая снижение жизнеспособности дофаминергических нейронов. The aim of this work was to study the effect of Hemantane (N-(2-adamantyl)-hexamethyleneimine hydrochloride) on the level of pro-inflammatory cytokines IL-1β, IL-6, interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) in the nigrocaudate complex of mice in early and late clinical phases of experimental Parkinsonian syndrome (PS) to elucidate its antiparkinsonian effect. Material and methods: The early and late clinical phases of PS were created in C57BL / 6J mice by 4 intraperitoneal injections at 2-h intervals of a proneurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), at a dose of 12 mg/kg or 20 mg/kg. Hemantane was injected intraperitoneally at a dose of 20 mg/kg 30 min before each MPTP administration. Concentrations of cytokines in mouse brain structures were measured by enzyme-linked immunosorbent assay (ELISA) using Cloud-Clone Corporation (USA) test systems and an ImmunoChem-2100 (USA) ELISA reader. Results: Concentrations of IL-1β, IL-6, IFN-γ, and TNF-α in the nigrocaudate complex were increased both in the early and late phases of PS. Prior administration of hemantane reduced the content of IL-1β, IFN-γ, and TNF-α in the nigrocaudate complex at the early phase and the content of only one of the 4 studied cytokines (IL-6) at the late phase of PS. It was assumed that the antiparkinsonian effect of hemantane at the early clinical stage of MPTP-induced PS involves a decrease in proinflammatory cytokines in the nigrostriatal system, which prevents the impairment of the viability of dopaminergic neurons.


2021 ◽  
Vol 30 ◽  
pp. 096368972110397
Author(s):  
Ming Yao ◽  
Anna Domogatskaya ◽  
Nils Ågren1 ◽  
Masaaki Watanabe ◽  
Kazuaki Tokodai ◽  
...  

During intra-portal pancreatic islet transplantation (PITx), innate immune reactions such as the instant blood mediated inflammatory reaction (IBMIR) cause an immediate loss of islets. The non-hematopoietic erythropoietin analogue cibinetide has previously shown islet-protective effects in mouse PITx. Herein, we aimed to confirm cibinetide’s efficacy on human islets, and to characterize its effect on IBMIR. We cultured human islets with pro-inflammatory cytokines for 18 hours with or without cibinetide. ATP content and caspase 3/7 activity were measured. Dynamic glucose perfusion assay was used to evaluate islet function. To evaluate cibinetides effect on IBMIR, human islets were incubated in heparinized polyvinyl chloride tubing system with ABO compatible blood and rotated for 60 minutes to mimic the portal vein system. Moreover, human islets were transplanted into athymic mice livers via the portal vein with or without perioperative cibinetide treatment. The mice were sacrificed six days following transplantation and the livers were analyzed for human insulin and serum for human C-peptide levels. Histological examination of recipient livers to evaluate islet graft infiltration by CD11b+ cells was performed. Our results show that cibinetide maintained human islet ATP levels and reduced the caspase 3/7 activity during culture with pro-inflammatory cytokines and improved their insulin secreting capacity. In the PVC loop system, administration of cibinetide reduced the IBMIR-induced platelet consumption. In human islet to athymic mice PITx, cibinetide treatment showed an increased amount of human insulin in the livers and higher serum human C-peptide, while histological examination of the livers showed reduced infiltration of pro-inflammatory CD11b+ cells around islets grafts compared to the controls. In summary, Cibinetide protected isolated human islets in a pro-inflammatory milieu and reduced IBMIR related platelet consumption. It improved engraftment of human islets in athymic mice. The study confirms that cibinetide is a promising agent to be used in clinical PITx.


Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 728
Author(s):  
Hira Shakoor ◽  
Jack Feehan ◽  
Vasso Apostolopoulos ◽  
Carine Platat ◽  
Ayesha Salem Al Dhaheri ◽  
...  

Functional and nutraceutical foods provide an alternative way to improve immune function to aid in the management of various diseases. Traditionally, many medicinal products have been derived from natural compounds with healing properties. With the development of research into nutraceuticals, it is becoming apparent that many of the beneficial properties of these compounds are at least partly due to the presence of polyphenols. There is evidence that dietary polyphenols can influence dendritic cells, have an immunomodulatory effect on macrophages, increase proliferation of B cells, T cells and suppress Type 1 T helper (Th1), Th2, Th17 and Th9 cells. Polyphenols reduce inflammation by suppressing the pro-inflammatory cytokines in inflammatory bowel disease by inducing Treg cells in the intestine, inhibition of tumor necrosis factor-alpha (TNF-α) and induction of apoptosis, decreasing DNA damage. Polyphenols have a potential role in prevention/treatment of auto-immune diseases like type 1 diabetes, rheumatoid arthritis and multiple sclerosis by regulating signaling pathways, suppressing inflammation and limiting demyelination. In addition, polyphenols cause immunomodulatory effects against allergic reaction and autoimmune disease by inhibition of autoimmune T cell proliferation and downregulation of pro-inflammatory cytokines (interleukin-6 (IL-6), IL-1, interferon-γ (IFN-γ)). Herein, we summarize the immunomodulatory effects of polyphenols and the underlying mechanisms involved in the stimulation of immune responses.


Molecules ◽  
2019 ◽  
Vol 24 (11) ◽  
pp. 2035 ◽  
Author(s):  
Bo Zhang ◽  
Ping-Ping Wang ◽  
Kai-Li Hu ◽  
Li-Na Li ◽  
Xue Yu ◽  
...  

There is growing evidence that neuroinflammation is closely linked to depression. Honokiol, a biologically active substance extracted from Magnolia officinalis, which is widely used in traditional Chinese medicine, has been shown to exert significant anti-inflammatory effects and improve depression-like behavior caused by inflammation. However, the specific mechanism of action of this activity is still unclear. In this study, the lipopolysaccharide (LPS) mouse model was used to study the effect of honokiol on depression-like behavior induced by LPS in mice and its potential mechanism. A single administration of LPS (1 mg/kg, intraperitoneal injection) increased the immobility time in the forced swimming test (FST) and tail suspension test (TST), without affecting autonomous activity. Pretreatment with honokiol (10 mg/kg, oral administration) for 11 consecutive days significantly improved the immobility time of depressed mice in the FST and TST experiments. Moreover, honokiol ameliorated LPS-induced NF-κB activation in the hippocampus and significantly reduced the levels of the pro-inflammatory cytokines; tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and interferon γ (IFN-γ). In addition, honokiol inhibited LPS-induced indoleamine 2,3-dioxygenase (IDO) activation and quinolinic acid (a toxic product) increase and reduced the level of free calcium in brain tissue, thereby inhibiting calcium overload. In summary, our results indicate that the anti-depressant-like effects of honokiol are mediated by its anti-inflammatory effects. Honokiol may inhibit the LPS-induced neuroinflammatory response through the NF-κB signaling pathway, reducing the levels of related pro-inflammatory cytokines, and furthermore, this may affect tryptophan metabolism and increase neuroprotective metabolites.


Genes ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1694
Author(s):  
Tina Fløyel ◽  
Caroline Frørup ◽  
Joachim Størling ◽  
Flemming Pociot

Emerging evidence suggests that several of the lysosomal cathepsin proteases are genetically associated with type 1 diabetes (T1D) and participate in immune-mediated destruction of the pancreatic β cells. We previously reported that the T1D candidate gene cathepsin H is downregulated by pro-inflammatory cytokines in human pancreatic islets and regulates β-cell function, apoptosis, and disease progression in children with new-onset T1D. In the present study, the objective was to investigate the expression patterns of all 15 known cathepsins in β-cell model systems and examine their role in the regulation of cytokine-induced apoptosis. Real-time qPCR screening of the cathepsins in human islets, 1.1B4 and INS-1E β-cell models identified several cathepsins that were expressed and regulated by pro-inflammatory cytokines. Using small interfering RNAs to knock down (KD) the cytokine-regulated cathepsins, we identified an anti-apoptotic function of cathepsin C as KD increased cytokine-induced apoptosis. KD of cathepsin C correlated with increased phosphorylation of JNK and p38 mitogen-activated protein kinases, and elevated chemokine CXCL10/IP-10 expression. This study suggests that cathepsin C is a modulator of β-cell survival, and that immune modulation of cathepsin expression in islets may contribute to immune-mediated β-cell destruction in T1D.


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