miR-29a up-regulation in AR42J cells contributes to apoptosis via targeting TNFRSF1A gene

Qiang Fu1, Tao Qin1, Lin Chen1

  • 1Qiang Fu, Tao Qin, Lin Chen, Chuan-Jiang Liu, Xu Zhang, Yu-Zhu Wang, Ming-Xing Hu, Hao-Yuan Chu, Hong-Wei Zhang, Department of Hepatobiliary Pancreatic Surgery, People's Hospital of Zhengzhou University, School of Medicine, Zhengzhou University, Zhengzhou 450003, Henan Province, China.

Abstract

Insights

MicroRNA-29a (miR-29a) expression increases in rat acute pancreatitis and promotes acinar cell apoptosis by upregulating TNFRSF1A. This finding offers insights into pancreatitis mechanisms and potential therapeutic targets.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Gastroenterology

Background:

  • Acute pancreatitis (AP) is a severe inflammatory condition of the pancreas.
  • MicroRNAs (miRNAs) play crucial roles in regulating cellular processes, including apoptosis.
  • The specific role of miR-29a in the pathogenesis of acute pancreatitis remains largely unexplored.

Purpose of the Study:

  • To investigate the expression levels of miR-29a in a rat model of acute pancreatitis.
  • To elucidate the functional role of miR-29a in regulating apoptosis of pancreatic acinar cells (AR42J).
  • To identify the potential target gene of miR-29a involved in apoptosis.

Main Methods:

  • Acute edematous pancreatitis (AEP) induced in rats using L-arginine; apoptosis assessed by TUNEL assay.
  • miRNA chip assay and qRT-PCR used to quantify miR-29a expression in pancreatic tissue and AR42J cells.
  • AR42J cells transfected with miR-29a mimic or antisense oligonucleotide (AMO); apoptosis analyzed by flow cytometry; TNFRSF1A expression assessed by qRT-PCR and Western blot; target validation via luciferase assay.

Main Results:

  • miR-29a expression was significantly upregulated in the AEP rat model and in TNF-α-induced AR42J cell apoptosis.
  • Overexpression of miR-29a using mimic enhanced AR42J cell apoptosis and TNFRSF1A expression.
  • Inhibition of miR-29a using AMO reduced AR42J cell apoptosis and TNFRSF1A expression, suggesting TNFRSF1A as a target gene.

Conclusions:

  • miR-29a expression is elevated during acute pancreatitis and promotes pancreatic acinar cell apoptosis.
  • miR-29a appears to exert its pro-apoptotic effect by upregulating the expression of its target gene, TNFRSF1A.
  • These findings highlight miR-29a as a potential mediator in acute pancreatitis pathogenesis and a target for therapeutic intervention.

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