Induction of stress proteins in a panel of mouse tissues by fever-range whole body hyperthermia

When exposed to environmental stress, cell survival is supported by the upregulation of stress proteins such as heat shock proteins (HSPs) or glucose regulated proteins (GRPs), which help prevent protein denaturation. To begin to characterize the ability of a physiologically relevant heat exposure to induce stress protein expression, the cerebellum, cerebrum, colon, heart, kidney, liver, lung, lymph nodes, muscle, serum and thymus were extracted from BALB/c mice at various times after fever-range whole body hyperthermia (FR-WBH, 39.5-40 degrees C for 6 h) treatment. The expression of three stress proteins, HSP70, HSP110 and GRP170, was determined in these tissues and serum and compared to constitutive levels in control tissues and serum using Western analysis. Constitutive expression of GRP170 was not affected by FR-WBH in any tissue. In contrast, FR-WBH did enhance HSP expression: HSP70 in heart, kidney, lung, lymph nodes and thymus; and HSP110 in lung, lymph nodes and thymus. The lymphoid tissues displayed the most consistent upregulation of both HSP70 and HSP110 upon FR-WBH treatment. The apparent sensitivity of immunologically relevant tissues to FR-WBH may relate to the enhanced immune responses that are observed during febrile temperatures.