Tuberculosis-infected macrophage exosomal miR-125b-5p induces osteoporosis by targeting IGF2 through the PI3K/AKT

Chenhao Zhao1,2, Qiuwei Li1,2, PeiLin Jin1,2

  • 1Department of Orthopedics and Spine Surgery, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, 230022, Anhui, China.

Abstract

Insights

Tuberculosis (TB) triggers osteoporosis by increasing exosomal miR-125b-5p, which targets IGF2 and disrupts bone formation. Targeting this pathway offers a potential therapeutic strategy for TB-induced bone loss.

Area of Science:

  • Molecular Biology
  • Immunology
  • Bone Metabolism

Background:

  • Tuberculosis (TB) can cause systemic complications like osteoporosis, especially in immunocompromised individuals.
  • Exosomal microRNAs (miRNAs) from TB-infected macrophages influence bone metabolism.
  • This study focuses on exosomal miR-125b-5p's role in TB-induced osteoporosis.

Purpose of the Study:

  • Investigate how exosomal miR-125b-5p from TB-infected macrophages contributes to osteoporosis.
  • Determine if miR-125b-5p targets insulin-like growth factor 2 (IGF2).
  • Elucidate the modulation of the PI3K/AKT signaling pathway by exosomal miR-125b-5p.

Main Methods:

  • Analysis of NHANES data for bone mineral density comparison.
  • In vitro studies using Mycobacterium tuberculosis-infected mouse macrophages and exosome isolation.
  • Western blot, flow cytometry, and bioinformatics to assess miR-125b-5p's role in osteogenic markers.
  • In vivo mouse models to evaluate exosomal miR-125b-5p's impact on bone.

Main Results:

  • Exosomes from TB-infected macrophages showed elevated miR-125b-5p levels.
  • miR-125b-5p targeted IGF2, inhibiting the PI3K/AKT pathway and impairing osteoblast function.
  • Knockdown of miR-125b-5p partially restored osteogenic markers and bone density.
  • IGF2 silencing exacerbated bone loss, confirming its critical role.

Conclusions:

  • Exosomal miR-125b-5p from TB-infected macrophages promotes osteoporosis by disrupting the IGF2/PI3K/AKT signaling axis.
  • Targeting this pathway presents a potential therapeutic strategy for TB-induced osteoporosis.
  • Further clinical studies are needed to validate findings and explore therapeutic options.

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