TGFβ2 mediates oxidative stress-induced epithelial-to-mesenchymal transition of bladder smooth muscle

In Vitro Cell Dev Biol Anim. 2024 Aug;60(7):793-804. doi: 10.1007/s11626-024-00864-9. Epub 2024 Feb 26.

Abstract

Bladder outlet obstruction (BOO) is the primary clinical manifestation of benign prostatic hyperplasia, the most common urinary system disease in elderly men, and leads to associated lower urinary tract symptoms. Although BOO is reportedly associated with increased systemic oxidative stress (OS), the underlying mechanism remains unclear. The elucidation of this mechanism is the primary aim of this study. A Sprague-Dawley rat model of BOO was constructed and used for urodynamic monitoring. The bladder tissue of rats was collected and subjected to real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR), histological examination, and immunohistochemical staining. Through bioinformatics prediction, we found that transforming growth factor β2 (TGFβ2) expression was upregulated in rats with BOO compared with normal bladder tissue. In vitro analyses using primary bladder smooth muscle cells (BSMCs) revealed that hydrogen peroxide (H2O2) induced TGFβ2 expression. Moreover, H2O2 induced epithelial-to-mesenchymal transition (EMT) by reducing E-cadherin, an endothelial marker and CK-18, a cytokeratin maker, and increasing mesenchymal markers, including N-cadherin, vimentin, and α-smooth muscle actin (α-SMA) levels. The downregulation of TGFβ2 expression in BSMCs using siRNA technology alleviated H2O2-induced changes in EMT marker expression. The findings of the study indicate that TGFβ2 plays a crucial role in BOO by participating in OS-induced EMT in BSMCs.

Keywords: Benign prostatic hyperplasia; Bladder outlet obstruction; Epithelial-to-mesenchymal transition; Oxidative stress; Transforming growth factor β2.

MeSH terms

  • Animals
  • Epithelial-Mesenchymal Transition*
  • Hydrogen Peroxide / pharmacology
  • Male
  • Muscle, Smooth / metabolism
  • Muscle, Smooth / pathology
  • Myocytes, Smooth Muscle / metabolism
  • Myocytes, Smooth Muscle / pathology
  • Oxidative Stress*
  • Rats
  • Rats, Sprague-Dawley*
  • Transforming Growth Factor beta2* / metabolism
  • Urinary Bladder Neck Obstruction / metabolism
  • Urinary Bladder Neck Obstruction / pathology
  • Urinary Bladder* / metabolism
  • Urinary Bladder* / pathology

Substances

  • Hydrogen Peroxide
  • Transforming Growth Factor beta2
  • Tgfb2 protein, rat