The Impact of Pro-Inflammatory Cytokines on Alternative Splicing Patterns in Human Islets

AbstractPrecursor messenger RNA (pre-mRNA) splicing is a fundamental step in eukaryotic gene expression that systematically removes non-coding regions (introns) and ligates coding regions (exons) into a continuous message (mature mRNA). This process is highly regulated and can be highly flexible through a process known as alternative splicing, which allows for several transcripts to arise from a single gene, thereby greatly increasing genetic plasticity and the diversity of proteome. Alternative splicing is particularly prevalent in neuronal cells, where the splicing patterns are continuously changing to maintain cellular homeostasis and promote neurogenesis, migration and synaptic function. The continuous changes in splicing patterns and a high demand on many cis- and trans-splicing factors contribute to the susceptibility of neuronal tissues to splicing defects. The resultant neurodegenerative diseases are a large group of disorders defined by a gradual loss of neurons and a progressive impairment in neuronal function. Several of the most common neurodegenerative diseases involve some form of splicing defect(s), such as Alzheimer’s disease, Parkinson’s disease and spinal muscular atrophy. Our growing understanding of RNA splicing has led to the explosion of research in the field of splice-switching antisense oligonucleotide therapeutics. Here we review our current understanding of the effects alternative splicing has on neuronal differentiation, neuronal migration, synaptic maturation and regulation, as well as the impact on neurodegenerative diseases. We will also review the current landscape of splice-switching antisense oligonucleotides as a therapeutic strategy for a number of common neurodegenerative disorders.

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Macrophage-associated pro-inflammatory state in human islets from obese individuals

Nutrition and Diabetes ◽

10.1038/s41387-019-0103-z ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 9

Author(s):

Wei He ◽

Ting Yuan ◽

Kathrin Maedler

Keyword(s):

Inflammatory Cytokines ◽

Macrophage Polarization ◽

Human Islets ◽

Macrophage Phenotype ◽

Inflammatory State ◽

Obese Control ◽

Inflammatory Macrophages ◽

Inflammatory Macrophage ◽

Pro Inflammatory Cytokines

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.

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The Impact of Pro-inflammatory Cytokines on ROS Mediated Liver Damage

Free Radical Biology and Medicine ◽

10.1016/j.freeradbiomed.2017.10.326 ◽

2017 ◽

Vol 112 ◽

pp. 206 ◽

Cited By ~ 1

Author(s):

Andras Meszaros ◽

Adelheid Weidinger ◽

Sergiu Dumitrescu ◽

Andrea V Müllebner ◽

Johanna Catharina Duvigneau ◽

...

Keyword(s):

Inflammatory Cytokines ◽

Liver Damage ◽

The Impact ◽

Pro Inflammatory Cytokines

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A randomised controlled trial of two supervised exercise regimens and their impact on inflammatory burden in patients with intermittent claudication

Vascular ◽

10.1177/1708538115617622 ◽

2015 ◽

Vol 24 (3) ◽

pp. 264-272 ◽

Cited By ~ 4

Author(s):

CL Delaney ◽

JI Spark

Keyword(s):

Intermittent Claudication ◽

Inflammatory Cytokines ◽

Acute Exercise ◽

Interleukin 12 ◽

Acute Bout ◽

Supervised Exercise ◽

Group 2 ◽

The Impact ◽

Pro Inflammatory Cytokines ◽

Group 1

Objective This study assesses the impact of treadmill-based SET alone or in combination with resistance training on systemic inflammatory response, in patients with intermittent claudication (IC). Methods Thirty-five patients with IC were randomised to 12 weeks of treadmill-only SET (Group 1) or a combination of treadmill and lower-limb resistance SET (Group 2). A panel of pro- and anti-inflammatory markers were assessed before, during and after the SET. Results Over the duration of SET, homocysteine increased within Group 1 (12.0–15.5 µmol/L, p = 0.003) but not Group 2, (13.7–14.7 µmol/) while neutrophil elastase (NE) increased within Group 2 (174.5–238.2 ng/mL, p = 0.007) but not Group 1 (300.8–312.0 ng/mL). In both groups NE increased following acute exercise at the start of the SET. Differences in cytokine expression was evident between the two groups (in Group 1, pro-inflammatory cytokines interleukin-12 and interferon-gamma decreased following an acute bout of exercise at the end of SET, where as in Group 2 pro-inflammatory cytokines interleukin-6 and 8 were seen to increase after an acute bout of exercise at the end of SET). Conclusion SET in patients with IC influences the complex immune-modulatory state of atherosclerosis through inflammatory pathways that induce both pro-inflammatory and immunosuppressive responses.

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Cutaneous glucocorticoid receptor sensitivity and pro-inflammatory cytokine levels in antidepressant-resistant depression

Psychological Medicine ◽

10.1017/s003329170500632x ◽

2005 ◽

Vol 36 (1) ◽

pp. 37-43 ◽

Cited By ~ 51

Author(s):

PETER FITZGERALD ◽

SINEAD M. O'BRIEN ◽

PAUL SCULLY ◽

KIM RIJKERS ◽

LUCINDA V. SCOTT ◽

...

Keyword(s):

Glucocorticoid Receptor ◽

Inflammatory Cytokines ◽

Topical Steroid ◽

Depression Scale ◽

Topical Steroids ◽

Hamilton Depression Scale ◽

Tnf Α ◽

Resistant Depression ◽

The Impact ◽

Pro Inflammatory Cytokines

Background. There is evidence to indicate that peripheral glucocorticoid receptor (GR) function is reduced in major depression, and a possible molecular explanation for this is the impact of raised pro-inflammatory cytokines. The topical steroid vasoconstriction assay provides a convenient probe of peripheral GR function. The present study sought to assess the sensitivity of peripheral GRs in antidepressant-resistant major depressives and investigate the association between GR sensitivity and circulating plasma cytokines.Method. Nineteen antidepressant-resistant depressives together with age- and sex-matched healthy controls underwent the steroid vasoconstriction assay using three commercial preparations of corticosteroids containing clobetasol propionate 0·05%, betamethasone valerate 0·1%, and clobetasone butyrate 0·05%, corresponding to very potent, potent, and moderately potent steroid creams respectively. The pro-inflammatory cytokines, tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were measured using enzyme-linked immunosorbent assays. The severity of the depressive episode was assessed using the Hamilton Depression Scale (HAMD).Results. Depressed subjects had a significantly reduced vasoconstriction response across all three strengths of steroid. They also had significantly higher concentrations of TNF-α and IL-6. There was a significant inverse correlation between TNF-α concentration and vasoconstriction response and also between the HAMD score and vasoconstriction response.Conclusions. These findings suggest that cutaneous GR function is abnormal in antidepressant-resistant depression, that circulating TNF-α may play a significant role in this abnormality and that the efficacy of topical steroids in antidepressant-resistant depressives is reduced.

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The FcγRIII Engagement Augments PMA-Stimulated Neutrophil Extracellular Traps (NETs) Formation by Granulocytes Partially via Cross-Talk between Syk-ERK-NF-κB and PKC-ROS Signaling Pathways

Biomedicines ◽

10.3390/biomedicines9091127 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1127

Author(s):

Cheng-Hsun Lu ◽

Ko-Jen Li ◽

Cheng-Han Wu ◽

Chieh-Yu Shen ◽

Yu-Min Kuo ◽

...

Keyword(s):

Signaling Pathways ◽

Inflammatory Cytokines ◽

Cross Talk ◽

Neutrophil Extracellular Traps ◽

Ros Generation ◽

Dependent Manner ◽

Extracellular Traps ◽

Tnf Α ◽

The Impact ◽

Pro Inflammatory Cytokines

Polymorphonuclear neutrophils (PMNs) are the most abundant white blood cell in the circulation capable of neutrophil extracellular traps (NETs) formation after stimulation. Both NADPH oxidase-dependent and -independent pathways are involved in NET formation. The IgG is the most abundant immunoglobulin in human serum. However, the impact of the circulating IgG on NET formation is totally unexplored. In this study, the all-trans retinoic acid (ATRA)-induced mature granulocytes (dHL-60) were pre-treated with monomeric human IgG, papain-digested Fab fragment, crystallizable IgG Fc portion, rituximab (a human IgG1), or IgG2. The NET formation of the dHL-60 in the presence/absence of phorbol 12-myristate 13-acetate (PMA) stimulation was then measured by the fluorescent area after SYTOX green nucleic acid stain. The intracellular reactive oxygen species (ROS) generation was measured by flow cytometry. Total and phosphorylated Syk, SHP-1, and ERK were detected by immunoblot. We found that human monomeric IgG and its subclasses IgG1 and IgG2 per se induced negligible NET formation of dHL-60, but the FcγRIII engagement by these IgG subclasses and Fc portion augment PMA-stimulated dHL-60 NET formation in a dose-dependent manner. Furthermore, we found that increased Syk and ERK phosphorylation, intracellular ROS generation, and pro-inflammatory cytokines, IL-8 and TNF-α, production could be induced after FcγRIII engagement. Blocking FcγRIII engagement by a specific antibody diminished the augmented NET formation. In conclusion, we discovered that cross-talk between FcγRIII engagement-induced Syk-ERK and PMA-induced PKC signaling pathways augment NET formation of dHL-60 via increased ROS generation and pro-inflammatory cytokines, IL-8 and TNF-α, production.

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The Impact of Pro-Inflammatory Cytokines on Alternative Splicing Patterns in Human Islets

10.2337/figshare.16828255 ◽

2021 ◽

Author(s):

Wenting Wu ◽

Farooq Syed ◽

Edward Simpson ◽

Chih-Chun Lee ◽

Jing Liu ◽

...

Keyword(s):

Alternative Splicing ◽

Mhc Class Ii ◽

Single Molecule ◽

Rna Binding ◽

Rna Binding Proteins ◽

Ex Vivo ◽

Class Ii ◽

Human Islets ◽

Β Cell ◽

The Impact

Alternative splicing (AS) within the β cell has been proposed as one potential pathway that may exacerbate autoimmunity and unveil novel immunogenic epitopes in type 1 diabetes (T1D). We employed a computational strategy to prioritize pathogenic splicing events in human islets treated with IL-1β + IFN-γ as an <i>ex vivo</i> model of T1D and coupled this analysis with a k-mer based approach to predict RNA binding proteins involved in AS. In total, 969 AS events were identified in cytokine-treated islets, with the majority (44.8%) involving a skipped exon. ExonImpact identified 129 events predicted to impact protein structure. AS occurred with high frequency in MHC Class II-related mRNAs, and targeted qPCR validated reduced inclusion of Exon5 in the MHC Class II gene HLA-DMB. Single-molecule RNA FISH confirmed increased HLA-DMB splicing in pancreatic sections from human donors with established T1D and autoantibody positivity. Serine and Arginine Rich Splicing Factor 2 was implicated in 37.2% of potentially pathogenic events, including Exon5 exclusion in HLA-DMB. Together, these data suggest that dynamic control of AS plays a role in the β cell response to inflammatory signals during T1D evolution.

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The Impact of Pro-Inflammatory Cytokines on Alternative Splicing Patterns in Human Islets

10.2337/figshare.16828255.v1 ◽

2021 ◽

Author(s):

Wenting Wu ◽

Farooq Syed ◽

Edward Simpson ◽

Chih-Chun Lee ◽

Jing Liu ◽

...

Keyword(s):

Alternative Splicing ◽

Mhc Class Ii ◽

Single Molecule ◽

Rna Binding ◽

Rna Binding Proteins ◽

Ex Vivo ◽

Class Ii ◽

Human Islets ◽

Β Cell ◽

The Impact

Alternative splicing (AS) within the β cell has been proposed as one potential pathway that may exacerbate autoimmunity and unveil novel immunogenic epitopes in type 1 diabetes (T1D). We employed a computational strategy to prioritize pathogenic splicing events in human islets treated with IL-1β + IFN-γ as an <i>ex vivo</i> model of T1D and coupled this analysis with a k-mer based approach to predict RNA binding proteins involved in AS. In total, 969 AS events were identified in cytokine-treated islets, with the majority (44.8%) involving a skipped exon. ExonImpact identified 129 events predicted to impact protein structure. AS occurred with high frequency in MHC Class II-related mRNAs, and targeted qPCR validated reduced inclusion of Exon5 in the MHC Class II gene HLA-DMB. Single-molecule RNA FISH confirmed increased HLA-DMB splicing in pancreatic sections from human donors with established T1D and autoantibody positivity. Serine and Arginine Rich Splicing Factor 2 was implicated in 37.2% of potentially pathogenic events, including Exon5 exclusion in HLA-DMB. Together, these data suggest that dynamic control of AS plays a role in the β cell response to inflammatory signals during T1D evolution.

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Cibinetide Protects Isolated Human Islets in a Stressful Environment and Improves Engraftment in the Perspective of Intra Portal Islet Transplantation

Cell Transplantation ◽

10.1177/09636897211039739 ◽

2021 ◽

Vol 30 ◽

pp. 096368972110397

Author(s):

Ming Yao ◽

Anna Domogatskaya ◽

Nils Ågren1 ◽

Masaaki Watanabe ◽

Kazuaki Tokodai ◽

...

Keyword(s):

Portal Vein ◽

Histological Examination ◽

Human Insulin ◽

Inflammatory Cytokines ◽

Caspase 3 ◽

Human Islets ◽

Human Islet ◽

Athymic Mice ◽

C Peptide ◽

Pro Inflammatory Cytokines

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.

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