Journal of Applied Physiology, Vol 79, Issue 5 1673-1678, Copyright © 1995 by American Physiological Society

ARTICLES

HSP70 accumulation in tissues of heat-stressed rats is blunted with advancing age

K. C. Kregel, P. L. Moseley, R. Skidmore, J. A. Gutierrez and V. Guerriero Jr
Department of Exercise Science, University of Iowa, Iowa City 52242, USA.

To determine whether aging results in reduced accumulation of the 70-kDa heat shock protein (HSP70) in response to a thermal challenge, experiments were conducted in conscious and freely moving mature (12-mo-old) and senescent (24-mo-old) male Fischer 344 rats. Rats were assigned to a euthermic control group or a nonexertionally heated group that was exposed to an ambient temperature of 42 degrees C until colonic temperature reached 41 degrees C. Samples were subsequently obtained from the liver and myocardium, and absolute levels of both the constitutive and inducible forms of HSP70 were quantitated. Heat-stressed rats had significantly elevated HSP70 levels in the liver compared with the euthermic groups. Post hoc comparisons revealed that heat stress elicited marked elevations in liver HSP70 in mature rats compared with age-matched control animals. In contrast, HSP70 values were unchanged in the senescent heated group vs. the control group. In the myocardium, heat stress produced marked increases in HSP70 levels in both the mature and senescent groups compared with age-matched control animals, with accumulation significantly blunted in the senescent vs. mature rats. Thus the increases in liver and myocardial HSP70 accumulation in response to nonexertional heat stress are attenuated with senescence. Because these proteins are postulated to protect cells from injury and enhance cellular recovery from heat stress, the data suggest that an aging organism has a reduced ability to properly maintain cellular function and integrity after a thermal challenge.

This article has been cited by other articles:

				H. J. Zhang, S. R. Doctrow, L. W. Oberley, and K. C. Kregel Chronic antioxidant enzyme mimetic treatment differentially modulates hyperthermia-induced liver HSP70 expression with aging J Appl Physiol, April 1, 2006; 100(4): 1385 - 1391. [Abstract] [Full Text] [PDF]

				J. W. Starnes, A. M. Choilawala, R. P. Taylor, M. J. Nelson, and M. D. Delp Myocardial Heat Shock Protein 70 Expression in Young and Old Rats After Identical Exercise Programs J. Gerontol. A Biol. Sci. Med. Sci., August 1, 2005; 60(8): 963 - 969. [Abstract] [Full Text] [PDF]

				B. Gonzalez and R. Manso Induction, modification and accumulation of HSP70s in the rat liver after acute exercise: early and late responses J. Physiol., April 15, 2004; 556(2): 369 - 385. [Abstract] [Full Text] [PDF]

				K. C. Kregel Molecular Biology of Thermoregulation: Invited Review: Heat shock proteins: modifying factors in physiological stress responses and acquired thermotolerance J Appl Physiol, May 1, 2002; 92(5): 2177 - 2186. [Abstract] [Full Text] [PDF]

				Y. Oishi, K. Taniguchi, H. Matsumoto, A. Ishihara, Y. Ohira, and R. R. Roy Muscle type-specific response of HSP60, HSP72, and HSC73 during recovery after elevation of muscle temperature J Appl Physiol, March 1, 2002; 92(3): 1097 - 1103. [Abstract] [Full Text] [PDF]

				L. H. E. H. Snoeckx, R. N. Cornelussen, F. A. Van Nieuwenhoven, R. S. Reneman, and G. J. Van der Vusse Heat Shock Proteins and Cardiovascular Pathophysiology Physiol Rev, October 1, 2001; 81(4): 1461 - 1497. [Abstract] [Full Text] [PDF]

				D. M. Hall, G. L. Sattler, C. A. Sattler, H. J. Zhang, L. W. Oberley, H. C. Pitot, and K. C. Kregel Aging Lowers Steady-State Antioxidant Enzyme and Stress Protein Expression in Primary Hepatocytes J. Gerontol. A Biol. Sci. Med. Sci., June 1, 2001; 56(6): B259 - B267. [Abstract] [Full Text] [PDF]

				D. M. Hall, L. Xu, V. J. Drake, L. W. Oberley, T. D. Oberley, P. L. Moseley, and K. C. Kregel Aging reduces adaptive capacity and stress protein expression in the liver after heat stress J Appl Physiol, August 1, 2000; 89(2): 749 - 759. [Abstract] [Full Text] [PDF]

				C. C. Gray, M. Amrani, R. T. Smolenski, G. L. Taylor, and M. H. Yacoub Age dependence of heat stress mediated cardioprotection Ann. Thorac. Surg., August 1, 2000; 70(2): 621 - 626. [Abstract] [Full Text] [PDF]

				D. M. HALL, T. D. OBERLEY, P. M. MOSELEY, G. R. BUETTNER, L. W. OBERLEY, R. WEINDRUCH, and K. C. KREGEL Caloric restriction improves thermotolerance and reduces hyperthermia-induced cellular damage in old rats FASEB J, January 1, 2000; 14(1): 78 - 86. [Abstract] [Full Text]

				L. P. Perrault, P. Menasche, A. Bel, T. de Chaumaray, J. Peynet, A. Mondry, P. Olivero, R. Emanoil-Ravier, and J.-M. Moalic ISCHEMIC PRECONDITIONING IN CARDIAC SURGERY: A WORD OF CAUTION J. Thorac. Cardiovasc. Surg., November 1, 1996; 112(5): 1378 - 1386. [Abstract] [Full Text]

				H. J. Zhang, V. J. Drake, J. P. Morrison, L. W. Oberley, and K. C. Kregel Molecular Biology of Thermoregulation: Selected Contribution: Differential expression of stress-related genes with aging and hyperthermia J Appl Physiol, April 1, 2002; 92(4): 1762 - 1769. [Abstract] [Full Text] [PDF]