Skip to main content
Log in

Effect of Okadaic Acid, a Protein Phosphatase Inhibitor, on Heat Stress-Induced HSP72 Synthesis and Thermotolerance

  • Published:
Cardiovascular Drugs and Therapy Aims and scope Submit manuscript

Abstract

Heat stress proteins (HSPs), in particular HSP72, seem to play a major role in cell protection against lethal stresses such as hyperthermia or ischemia. HSP synthesis is negatively regulated by protein phosphatases, which are implicated in dephosphorylation processes. In the present study, we have investigated the effect of okadaic acid (OA, a protein phosphatase inhibitor) on heat stress-induced HSP72 synthesis and thermotolerance in smooth muscle cells (SMC).

SMC were heat stressed (42°C for 20 minutes) in the presence of 250 nM OA (HS+OA cells) or its vehicle (HS+V cells). Control (OA or V) cells were not heat stressed. HSP72 mRNA expression was determined 1, 1.5, 3, and 6 hours after heat stress by RT-PCR, and HSP72 synthesis was determined 6, 12, 24, 48, and 72 hours after heat stress by Western blotting. SMC survival of lethal hyperthermia (47°C for 90 minutes) was assessed 6, 24, and 48 hours after heat stress by a tetrazolium assay.

The maximal expression of HSP72 mRNA was markedly prolonged in HS+OA cells (until 6 hours after heat stress) compared to HS+V cells (1 hour after heat stress). The kinetics of HSP72 synthesis and thermotolerance of SMC were not different between HS+OA and HS+V cells. Baseline HSP72 mRNA and protein expression were similar in control V and OA cells.

In conclusion, okadaic acid treatment of SMC potentiated HSP72 mRNA expression without affecting heat stress-induced HSP72 synthesis and thermotolerance.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Mestril R, Dillmann WH. Heat shock proteins and protection against myocardial ischemia. J Mol Cell Cardiol 1995;27:45-52.

    Google Scholar 

  2. Kiang JG, Tsokos GC. Heat shock protein 70 kDa: molecular biology, biochemistry, and physiology. Pharmacol Ther 1998;80:183-201.

    Google Scholar 

  3. Beckmann RP, Mizzen LE, Welch WJ. Interaction of Hsp 70 with newly synthesized proteins: implication for protein folding and assembly. Science 1990;248:850-854.

    Google Scholar 

  4. Williams RS, Thomas JA, Fina M, German Z, Benjamin IJ. Human heat shock protein 70 (HSP70) protects murine cells from injury during metabolic stress. J Clin Invest 1993;92:503-508.

    Google Scholar 

  5. Mestril R, Chi SH, Sayen MR, O'reilly K, Dillmann WH. Expression of inducible stress protein 70 in rat heart myogenic cells confers protection against simulated ischemia-induced injury. J Clin Invest 1994;93:759-767.

    Google Scholar 

  6. Cumming DV, Heads RJ, Watson A, Latchman DS, Yellon DM. Differential protection of primary rat cardiocytes by transfection of specific heat stress proteins. J Mol Cell Cardiol 1996;28:2343-2349.

    Google Scholar 

  7. Heads RJ, Latchman DS, Yellon DM. Stable high level expression of a transfected human HSP70 gene protects a heart-derivated muscle cell line against thermal stress. J Mol Cell Cardiol 1994;26:695-699.

    Google Scholar 

  8. Rabindran SK, Haroun RI, Clos J, Wisniewski J, Wu C. Regulation of heat shock factor trimer formation: role of a conserved leucine zipper. Science 1993;259:230-234.

    Google Scholar 

  9. Chang NT, Huang LE, Liu AY. Okadaic acid markedly potentiates the heat-induced hsp 70 promoter activity. J Biol Chem 1993;268:1436-1439.

    Google Scholar 

  10. Mivechi NF, Murai T, Hahn GM. Inhibitors of tyrosine and Ser/Thr phosphatases modulate the heat shock response. J Cell Biochem 1994;54:186-197.

    Google Scholar 

  11. Hardie DG, Haystead TA, Sim AT. Use of okadaic acid to inhibit protein phosphatases in intact cells. Methods Enzymol 1991;201:469-476.

    Google Scholar 

  12. Latchman DS. Heat shock proteins: protective effect and potential therapeutic use. Int J Mol Med 1998;2:375-381.

    Google Scholar 

  13. Lagneux C, Innocenti-Francillard P, Godin-Ribuot D, Bader M, Ribuot C. Heat stress-induced B1 receptor synthesis in the rat: an ex vivo study. Br J Pharmacol 1998;125:812-816.

    Google Scholar 

  14. Laemmli UK. Cleavage of structural proteins during the assembly of the head of the bacteriophage T4. Nature 1970;227:680-685.

    Google Scholar 

  15. Parat MO, Richard MJ, Favier A, Beani JC. Metal chelator NNNN-tetrakis-(2-pyridymethyl)ethylene diamine inhibits the induction of heat shock protein 70 synthesis by heat in cultured keratinocytes. Biol Trace Elem Res 1998;65:261-270.

    Google Scholar 

  16. Morris SD, Cumming DV, Latchman DS, Yellon DM. Specific induction of the 70-kD heat stress proteins by the tyrosine kinase inhibitor herbimycin-A protects rat neonatal cardiomyocytes. A new pharmacological route to stress protein expression? J Clin Invest 1996;97:706-712.

    Google Scholar 

  17. Carmichael J, Degraff WG, Gazdar AF, Minna JD, Mitchell JB. Evaluation of a tetrazolium-based semiautomated colorimetric assay: assessment of radiosensitivity. Cancer Res 1987;47:943-946.

    Google Scholar 

  18. Angelidis CE, Lazaridis I, Pagoulatos GN. Constitutive expression of heat-shock protein 70 in mammalian cells confers thermoresistance. Eur J Biochem 1991;199:35-39.

    Google Scholar 

  19. Li GC, Li LG, Liu YK, Mak JY, Chen LL, Lee WM. Thermal response of rat fibroblasts stably transfected with thehuman 70-kDa heat shock protein-encoding gene. Proc Natl Acad Sci USA 1991;88:1681-1685.

    Google Scholar 

  20. Chi SH, Mestril R. Stable expression of a human HSP70 gene in rat myogenic cell line confers protection against endotoxine. Am J Physiol 1996;270:C1017-C1021.

    Google Scholar 

  21. Marber MS, Mestril R, Chi SH, Sayen MR, Yellon DM, Dillmann WH. Overexpression of the rat inducible 70-kD heat stress protein in a transgenic mouse increase the resistance of the heart to ischemic injury. J Clin Invest 1995;95:1446-1456.

    Google Scholar 

  22. Plumier JC, Ross BM, Currie RW, et al. Transgenic mice overexpressing the human heat shock protein 70 have improved post-ischemic myocardial recovery. J Clin Invest 1995;95:1854-1860.

    Google Scholar 

  23. Hutter JJ, Mestril R, Tam EK, Sievers RE, Dillmann WH, Wolfe CL. Overexpression of heat shock protein 72 in transgenic mice decreases infarct size in vivo. Circulation 1996;94:1408-1411.

    Google Scholar 

  24. Radford NB, Fina M, Benjamin IJ, et al. Cardioprotective effects of 70-kDa heat shock protein in transgenic mice. Proc Natl Acad Sci USA 1996;93:2339-2342.

    Google Scholar 

  25. Jurivich DA, Sistonen L, Kroes RA, Morimoto RI. Effect of sodium salicylate on the human heat shock response. Science 1992;255:1243-1245.

    Google Scholar 

  26. Vigh L, Literati PN, Horvath I, et al. Bimoclomol: a nontoxic, hydroxylamine derivative with stress protein-inducing activity and cytoprotective effects. Nat Med 1997;3:1150-1154.

    Google Scholar 

  27. Larson JS, Schuetz TJ, Kingston RE. Activation in vitro of sequence-specific DNA binding by a human regulatory factor. Nature 1988;335:372-375.

    Google Scholar 

  28. Ding XZ, Tsokos GC, Kiang JG. Heat shock factor-1 protein in heat shock factor-1 gene-transfected human epidermoid A431 cells requires phosphorylation before inducing heat shock protein-70 production. J Clin Invest 1997;99:136-143.

    Google Scholar 

  29. Ding XZ, Tsokos GC, Kiang JG. Overexpression of HSP-70 inhibits the phosphorylation of HSF1 by activating protein phosphatase and inhibiting protein kinase C activity. FASEB J 1998;12:451-459.

    Google Scholar 

  30. Kim D, Ouyang H, Li GC. Heat shock protein hsp70 accelerates the recovery of heat-shocked mammalian cells through its modulation of heat shock transcription factor HSF1. Proc Natl Acad Sci USA 1995;92:2126-2130.

    Google Scholar 

  31. Chen KD, Chu JJ, Lai YK. Modulation of protein phosphorylation and stress protein expression by okadaic acid on heat shock cells. J Cell Biochem 1996;61:255-265.

    Google Scholar 

  32. Ito H, Hasegawa K, InagumaY, Kozawa O, Asano T, Kato K. Modulation of the stress-induced synthesis of stress proteins by a phorbol ester and okadaic acid. J Biochem 1995;118:629-634.

    Google Scholar 

  33. Currie RW, Tanguay RM. Analysis of RNA for transcripts for catalase and SP71 in rat hearts after in vivo hyperthermia. Biochem Cell Biol 1991;69:375-382.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Joyeux, M., Arnaud, C., Richard, MJ. et al. Effect of Okadaic Acid, a Protein Phosphatase Inhibitor, on Heat Stress-Induced HSP72 Synthesis and Thermotolerance. Cardiovasc Drugs Ther 14, 441–446 (2000). https://doi.org/10.1023/A:1007824502285

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/A:1007824502285

Navigation