Elevated TGF-β2 level in aqueous humor of cataract patients with high myopia: Potential risk factor for capsule contraction syndrome

J Cataract Refract Surg. 2016 Feb;42(2):232-8. doi: 10.1016/j.jcrs.2015.09.027.

Abstract

Purpose: To evaluate the level of transforming growth factor-β2 (TGF-β2) in the aqueous humor of highly myopic cataract patients and its correlation with capsule contraction syndrome.

Setting: Eye and ENT Hospital of Fudan University, Shanghai, China.

Design: Prospective comparative case series.

Methods: The highly myopic cataract patients were divided into the following 2 groups according to the Lens Opacity Classification System III: nuclear color (NC) 2 to 3 and NC 5 to 6. Aqueous humor TGF-β2 concentrations were assayed in the highly myopic cataract and age-related cataract groups. The TGF-β2, TGF-βRII (the type II receptor for TGF-β2), and α-smooth muscle actin (α-SMA) expressions in lens epithelial cells (LECs) were detected by real-time polymerase chain reaction and immunofluorescent staining.

Results: The study comprised 40 highly myopic cataract patients (40 eyes) and 20 patients (20 eyes) with age-related cataract as the control group. Compared with the control group, the highly myopic cataract group had significantly higher TGF-β2 concentration in the aqueous humor and increased TGF-βRII expression in LECs, especially in NC 5 to 6 cases. Expression of α-SMA was barely detectable in both groups.

Conclusion: In highly myopic cataract patients, especially those with dark nuclei, elevated aqueous humor TGF-β2 levels and the upregulated TGF-βRII expression in LECs might contribute to the pathogenesis of capsule contraction syndrome through transdifferentiation of LECs into myofibroblasts.

Financial disclosure: None of the authors has a financial or proprietary interest in any material or method mentioned.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / genetics
  • Actins / metabolism
  • Aged
  • Anterior Capsule of the Lens / metabolism
  • Anterior Capsule of the Lens / pathology*
  • Aqueous Humor / metabolism*
  • Cataract / metabolism*
  • Contracture / etiology*
  • Contracture / metabolism
  • Epithelial Cells / metabolism
  • Female
  • Fluorescent Antibody Technique, Indirect
  • Gene Expression Regulation / physiology
  • Humans
  • Lens, Crystalline / cytology
  • Male
  • Middle Aged
  • Myopia, Degenerative / metabolism*
  • Prospective Studies
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Real-Time Polymerase Chain Reaction
  • Receptor, Transforming Growth Factor-beta Type II
  • Receptors, Transforming Growth Factor beta / genetics
  • Receptors, Transforming Growth Factor beta / metabolism
  • Risk Factors
  • Transforming Growth Factor beta2 / metabolism*

Substances

  • ACTA2 protein, human
  • Actins
  • Receptors, Transforming Growth Factor beta
  • Transforming Growth Factor beta2
  • Protein Serine-Threonine Kinases
  • Receptor, Transforming Growth Factor-beta Type II