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Research Article

Protection of Islet Beta Cells from Iron Overload-Induced Injury by Long Non-Coding RNA Maternally Expressed Gene 3

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DOI:

10.3791/70942

June 12th, 2026

In This Article

Summary

Iron overload reduced MEG3 expression in pancreatic tissue. MEG3 may play a protective role against iron-induced islet β-cell apoptosis, potentially involving modulation of the NF-ĸB pathway. This mechanism may contribute to islet dysfunction in patients with β-TM with iron overload.

Abstract

Patients with beta-thalassemia major (β-TM) commonly present with abnormal glucose metabolism, and factors such as iron overload, chronic anaemia, hormonal imbalances, liver dysfunction and inflammation-associated insulin resistance are considered important contributors to pancreatic islet dysfunction. Long non-coding ribonucleic acids (lncRNAs) are increasingly recognised for their regulatory roles in cell apoptosis and glucose homeostasis. This study explores the function of the lncRNA, maternally expressed gene 3 (MEG3), in iron-induced islet β-cell injury. An iron-overload mouse model was induced via intraperitoneal injection of iron dextran. Iron deposition and tissue damage in the pancreas were evaluated using Prussian blue and hematoxylin and eosin staining, and MEG3 expression was quantified via reverse transcription polymerase chain reaction (RT-PCR). In vitro, MIN6 cells were transfected with MEG3 small interfering RNA to examine apoptosis via flow cytometry, and NF-kappa (ĸ)B signaling pathway activity was assessed by Western blotting. Histological staining confirmed significant iron deposition and structural damage in the pancreatic tissue of iron-overloaded mice. The RT-PCR analysis revealed a marked reduction of MEG3 expression in the pancreas (p<0.05). In vitro, MEG3 knockdown significantly increased apoptosis of MIN6 cells compared with controls. Western blot analysis showed an elevated level of NF-ĸB, indicating activation of the NF-ĸB signaling pathway in MEG3-silenced cells. These findings suggest that MEG3 downregulation may enhance islet β-cell apoptosis via NF-ĸB signaling under iron overload conditions. The MEG3 gene may play a protective role against iron-induced islet β-cell apoptosis, potentially involving modulation of the NF-ĸB pathway. This mechanism may contribute to islet dysfunction in patients with β-TM with iron overload.

Introduction

Beta (β)-thalassemias are a group of inherited hematological disorders characterized by reduced or absent β-globin chain production, resulting in chronic anemia and ineffective erythropoiesis1. In patients with transfusion-dependent β-thalassemia major (β-TM), repeated blood transfusions and hemolysis frequently lead to systemic iron overload, which can damage multiple organs and contribute to a range of endocrine complications, including abnormal glucose metabolism2. Additionally, chronic anemia increases the burden on the pancreas, hormonal imbalances affecting glucose regulation, liver dysfunction ....

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Protocol

The experimental protocols employed in the present study were approved by the Ethics Committee of Hainan General Hospital (protocol no. 2021-239). The US National Institutes of Health Guide for the Care and Use of Laboratory Animals and the Declaration of Helsinki were strictly followed in all experimental procedures. The reagents and the equipment used in this study are listed in the Table of Materials.

1. Animal Model and Experimental Design

Thirty-six male C57BL/6J mice (4 weeks old, approx. 20 g) were used in this study. All mice were housed under standard laboratory conditions....

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Results

Evaluation of the iron-overload mouse model and measurement of maternally expressed gene 3 expression in pancreatic tissues

To investigate the role of MEG3 in vivo, we established an iron-overload model in mice via intraperitoneal injection of iron dextran. Compared with the Control group, serum iron levels in the Model group were significantly increased (p<0.05) (Figure 1A). Histological examination revealed notable iron deposition in pancreat.......

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Discussion

Abnormal glucose metabolism is a common and serious complication in patients with β-TM, often manifesting as IGT or DM. In this study, we found that iron overload led to pancreatic injury and significantly decreased the expression of lncRNA MEG3 in pancreatic tissue, accompanied by increased apoptosis of islet β cells. Moreover, knockdown of MEG3 in MIN6 cells promoted β-cell apoptosis and was associated with NF-ĸB activation, indicating a potential mechanistic link between MEG3 and iron overload-indu.......

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Disclosures

The authors declare no conflicts of interest.

Acknowledgements

This research was funded by Hainan Provincial Natural Science Foundation of China (822QN445) and Foundation of Hainan Educational Committee (Hnky2024-30).

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Materials

List of materials used in this article
NameCompanyCatalog NumberComments
1M Tris-HCL (pH=6.8)Beijing Solarbio Science & Technology Co.,LtdT1020
50bp DNA LadderTIANGENMD108
50bp DNA LadderTIANGENMD108
6×DNA Loading BufferTIANGENGH101-01
6×DNA Loading BufferTRANSGH101-01
-80ºC refrigeratorBIOBASEBDF-86V348
ABI 7500 real-time PCR systemApplied Biosystems, USA
Annexin V-FITC/PI Apoptosis KitMULTI SCIENCESAP101-100-kit
BCA Protein Assay KitElabscience Biotechnology Co.,Ltd.E-BC-K318-M
Biopulverizerbiospec
BSABeijing Solarbio Science & Technology Co.,LtdA8020
C57BL/6J male miceGempharmatech Co,Jiangsu,China
CCK-8 Cell Proliferation Assay KitKeyGEN BioTECHKGA317
ChamQ Universal SYBR qPCR Master MixVazymeQ711-02
ChamQ Universal SYBR qPCR Master MixVazymeQ711-02
DMEMKeyGEN BioTECH
Flow cytometryACEA Biosciences, USANovoCyte 2060R
Fluorescence PCR instrumentBio-Rad Laboratories, Shanghai
GlycineBeijing Solarbio Science & Technology Co.,LtdG8200
High-capacity cDNA reverse transcription kitApplied Biosystems, Carlsbad, CA, USA
HiScript II Q RT SuperMix for qPCR (+gDNA wiper)VazymeR223-01
HiScript II Q RT SuperMix for qPCR (+gDNA wiper)VazymeR223-01
HRP conjugated Goat Anti-Mouse IgG (H+L)ServicebioGB233011/2000
HRP conjugated Goat Anti-Rabbit IgG (H+L)ServicebioGB233031/2000
Human LncRNA Array V5.0Arraystar,Rockville, Maryland, USA
Lipofectamine 3000 Transfection ReagentInvitrogenL3000015
Microarray scannerAgilent Technologies ,California, USA
MIN6 cellprocellKGM12800N
Mini-Bead-Beater-16biospec
Mouse Anti-GAPDHTransGen BiotechHC3011/2000
NanoDrop spectrophotometerNanoDrop Products, Wilmington, DE, USAND-2000
PAGE Pre-SolutionBeijing Solarbio Science & Technology Co.,LtdA1010
PrimersGeneray Biotech,Anhui, China
PrimeScript RT Reagent Kit with gDNA EraserCWBIO,Jiangsu, China
PVDFMilliporeIPVH00010
Rabbit Anti Baxproteintech50599-2-ig1/5000
Rabbit Anti Bcl-2abcamab1945831/1000
Rabbit Anti Caspase3abcamab1847871/2000
Rabbit Anti P65abcamab325361/8000
Rabbit Anti p-P65Affinityaf20061/1000
TB Green Premix Ex Taq IITaKaRa, Japan
TRIzolInvitrogen life technologies, Carlsbad, CA, USA
TRIzol reagent CWBIO,Jiangsu, China
Ultra-sensitive chemiluminescence imaging system instrumentBio-Rad Laboratories, ShanghaiChemi DocTM XRS+
Ultraviolet spectrophotometerNanoPhotometerNP80

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Tags

MEG3 ExpressionBeta Cell ApoptosisNF Kappa B PathwayPrussian Blue StainingReverse Transcription PCRFlow CytometryWestern Blot