J Korean Ophthalmol Soc.  2018 Nov;59(11):1056-1061. 10.3341/jkos.2018.59.11.1056.

Effects of Valproic Acid on the Survival of Human Tennon's Capsule Fibroblasts

• Lee SE
• Kim JW

• KMID: 2426367
• DOI: http://doi.org/10.3341/jkos.2018.59.11.1056

Abstract

PURPOSE
To investigate the effects of valproic acid on the survival of cultured human Tenon's capsule fibroblasts (HTFBs).
METHODS
Primary cultured HTFBs were exposed to 0, 0.25, 0.5, and 1.0 mM valproic acid with or without 0, 1.0, 2.5 µg/mL mitomycin C, and incubated for 5 days. Cell survival was assessed using an MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay and the degree of apoptosis was assessed by flow cytometry using annexin-V/propidium iodide double staining.
RESULTS
Valproic acid decreased the survival of HTFBs in a dose-dependent manner, and survival was further decreased by adding mitomycin C to valproic acid. Both valproic acid and mitomycin C induced apoptosis of HTFBs. Valproic acid induced less apoptosis than mitomycin C.
CONCLUSIONS
Valproic acid decreased the cellular survival of HTFBs and induced apoptosis. The antiproliferative effects of valproic acid were further enhanced by the addition of mitomycin C.

Keyword

Apoptosis; Fibroblast; Flow cytometry; Mitomycin C; Valproic acid

MeSH Terms

Apoptosis
Cell Survival
Fibroblasts*
Flow Cytometry
Humans*
Mitomycin
Tenon Capsule
Valproic Acid*
Mitomycin
Valproic Acid

Figure

• 

  Figure 1 Effect of valproic acid and mitomycin C on the survival of human Tenon's capsule fibroblasts. Both valproic acid (V, mM) and mitomycin C (M, µg/mL) decreased cellular survival in a dose-dependent manner (*p < 0.05).

• 

  Figure 2 Additive effect of valproic acid (V, mM) on the survival of human Tenon's capsule fibroblasts when co-exposed to 1.0 µg/mL of mitomycin C (M). Valproic acid further decreased mitomycin C-induced reduction of cellular survival significantly (*p < 0.05).

• 

  Figure 3 Additive effect of valproic acid (V, mM) on the survival of human Tenon's capsule fibroblasts when co-exposed to 2.5 µg/mL of mitomycin C (M). Valproic acid further decreased mitomycin C-induced reduction of cellular survival significantly (*p < 0.05).

• 

  Figure 4 Flow cytometric analysis of apoptosis using annexin-propidium iodide (PI) double staining. Cells in quadrant B1, B2, B3, B4 represent necrotic cells, late apoptotic cells, living cells and early apoptotic cells, respectively. (A) Exposed to 0.5 mM valproic acid. (B) Exposed to 2.5 µg/mL of mitomycin C. Cell count = 10,000. FITC = fluorescein isothiocyanate.

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