Effects of histone deacetylase inhibitors on rat mesangial cells

Area of Science:

• Nephrology
• Molecular Biology
• Pharmacology

Background:

• Glomerular mesangial cells (MCs) are implicated in progressive renal diseases through proliferation and extracellular matrix production.
• Histone deacetylase inhibitors (HDIs) have demonstrated antiproliferative and antifibrogenic properties in preclinical models.

Purpose of the Study:

• To investigate the effects of HDIs, specifically trichostatin A (TSA) and valproic acid, on mesangial cell proliferation and extracellular matrix production.
• To evaluate the therapeutic potential of HDIs in an in vivo model of glomerulonephritis.

Main Methods:

• Utilized the [(3)H]-thymidine incorporation assay to assess MC proliferation.
• Performed cell-cycle analysis to determine the phase of cell-cycle arrest induced by TSA.
• Measured protein synthesis of alpha-smooth muscle actin, transforming growth factor-beta1, and collagen.
• Administered TSA and valproic acid in an anti-Thy1.1-induced glomerulonephritis model to assess proteinuria.

Main Results:

• TSA significantly inhibited MC proliferation at nontoxic nanomolar concentrations, with valproic acid also showing inhibitory effects.
• TSA induced G(0)/G(1) cell-cycle arrest, associated with increased p21/Waf1 and p27/Kip1 expression.
• TSA suppressed key fibrotic markers including alpha-smooth muscle actin, transforming growth factor-beta1, and collagen synthesis.
• In vivo, both TSA and valproic acid treatments markedly reduced proteinuria in the glomerulonephritis model.

Conclusions:

• HDIs, including TSA and valproic acid, demonstrate potent antiproliferative and antifibrogenic effects on mesangial cells.
• HDIs show promise as a therapeutic strategy for mesangial proliferative diseases and glomerulosclerosis.
• The findings support further investigation of HDIs for treating progressive kidney diseases characterized by mesangial cell dysfunction.