J Korean Ophthalmol Soc.  2014 Aug;55(8):1195-1201.

Expression of TonEBP by Hypertonic and Hyperosmolar Stress in RGC-5 Cells

• Woo JE
• Kwon MY
• Chung SW
• Woo JM

Abstract

PURPOSE
In order to determine whether the Tonicity responsive enhancer binding protein (TonEBP) is expressed by hypertonic and hyperosmolar stress, TonEBP expression was investigated in the retinal ganglion cell (RGC) line, RGC-5 cells.
METHODS
After RGC-5 cells were cultured by Staurosporine, TonEBP expression was measured with Western immunoblotting analysis and real-time reverse transcription-polymerase chain reaction in 50 mM NaCl, 100 mM mannitol, 50 mM glucose, or 100 mM glucose at 3, 6, 12, and 24 hours after exposure to each environment.
RESULTS
In this study, the protein expression of TonEBP was determined to be statistically significantly checked in 50 mM NaCl after 3, and 6 hours, in 100 mM mannitol after 6 hours, and in 100 mM glucose after 3, and 6 hours. TonEBP messenger Ribonucleic acid (mRNA) expression was determined to be statistically significantly checked in 50 mM NaCl after 3 hours, in 100 mM mannitol after 3, and 24 hours, and in 50 mM glucose after 3, and 24 hours.
CONCLUSIONS
These results suggested that TonEBP was expressed by hypertonic and hyperosmolar stress at the protein and mRNA levels. Further studies are nedded to determine the role of TonEBP and the mechanism of expression and regulation of TonEBP.

Keyword

Hyperosmolar stress; Hypertonic stress; Retinal ganglion cell death; TonEBP expression

MeSH Terms

Blotting, Western
Glucose
Mannitol
NFATC Transcription Factors
Osmotic Pressure
Retinal Ganglion Cells
RNA
RNA, Messenger
Staurosporine
Glucose
Mannitol
NFATC Transcription Factors
RNA
RNA, Messenger
Staurosporine

Figure

• 

  Figure 1. Hypertonic inducers increase Tonicity responsive enhancer binding protein (TonEBP) protein expression in RGC-5 cells (A, C: 50 mM NaCl; B, D: 100 mM mannitol; -STD: before preconditioning; V: just after the preconditioning; 3: 3 hours after preconditioning; 6: 6 hours after preconditioning; 12: 12 hours after preconditioning; 24: 24 hours after preconditioning; *p< 0.05 by Mann-Whitney U -test). RGC = retinal ganglion cell; STD = staurosporine; GAPDH = glyceraldehyde-3-phosphate dehydrogenase.

• 

  Figure 2. High glucose increases Tonicity responsive enhancer binding protein (TonEBP) protein expression in RGC-5 cells (50 mM glucose, 100 mM glucose; A: Western blotting; B: Histogram; -STD: before preconditioning; V: just after the preconditioning; 3: 3 hours after preconditioning; 6: 6 hours after preconditioning; 12: 12 hours after preconditioning; 24: 24 hours after preconditioning; *p < 0.05 by Mann-Whitney U-test). RGC = retinal ganglion cell; STD = staurosporine; GAPDH = glyceraldehyde-3-phosphate dehydrogenase.

• 

  Figure 3. Hypertonic inducers increase Tonicity responsive enhancer binding protein (TonEBP) messenger Ribonucleic acid (mRNA) expression in RGC-5 cells (A: 50 mM NaCl; B: 100 mM mannitol; -STD: before preconditioning; +STD and -NaCl/-mannitol: just after the preconditioning; 3: 3 hours after preconditioning; 6: 6 hours after preconditioning; 12: 12 hours after preconditioning; 24: 24 hours after preconditioning; *p < 0.05 by Mann-Whitney U-test). RGC = retinal ganglion cell; STD = staurosporine.

• 

  Figure 4. High glucose increases Tonicity responsive enhancer binding protein (TonEBP) messenger Ribonucleic acid (mRNA) expression in RGC-5 cells (-STD: before preconditioning; +STD and -glucose: just after the preconditioning; 3: 3 hours after preconditioning; 6: 6 hours after preconditioning; 12: 12 hours after preconditioning; 24: 24 hours after preconditioning; *p < 0.05 by Mann-Whitney U-test). RGC = retinal ganglion cell; STD = staurosporine.

Reference

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