Class I HDACs specifically regulate E-cadherin expression in human renal epithelial cells.

Area of Science:

• Nephrology
• Molecular Biology
• Biochemistry

Background:

• Chronic kidney disease (CKD) is characterized by renal fibrosis and epithelial-mesenchymal transition (EMT).
• Histone deacetylase (HDAC) inhibition shows anti-fibrotic potential in various conditions.
• The specific roles of HDAC isoforms and classes in renal fibrosis are not well understood.

Purpose of the Study:

• To investigate the role of class I HDACs in regulating EMT and extracellular matrix (ECM) production in kidney cells.
• To determine the effects of specific HDAC inhibitors and knockdown of HDACs on fibrosis markers.

Main Methods:

• Utilized a human proximal tubular cell line (HK-2) stimulated with transforming growth factor β1 (TGF-β1).
• Administered various HDAC inhibitors (TSA, MS275, PCI34051, LMK235) and performed small interfering RNA (siRNA) knockdown of class I HDACs (HDAC1, 2, 3, 8).
• Assessed levels of EMT markers (E-cadherin, N-cadherin) and ECM proteins (collagen type I, fibronectin).

Main Results:

• HDAC inhibitors (TSA, MS275, PCI34051, LMK235) reduced TGF-β1-induced ECM proteins.
• TSA and MS275 restored E-cadherin levels, while PCI34051 and LMK235 did not.
• siRNA targeting HDAC8, but not HDAC1, 2, or 3, prevented or restored ECM protein and EMT marker levels.
• E-cadherin regulation was dependent on HDAC8 expression, not its enzymatic activity.

Conclusions:

• Class I HDACs, particularly HDAC8, are crucial regulators of EMT and ECM production in kidney cells.
• HDAC8 expression, rather than its activity, mediates E-cadherin regulation in this context.
• Targeting specific class I HDACs, like HDAC8, may offer therapeutic strategies for mitigating renal fibrosis in CKD.