Glucocorticoid pretreatment protects cardiac function and induces cardiac heat shock protein 72

G Valen, T Kawakami, P Tähepôld… - American Journal …, 2000 - journals.physiology.org
G Valen, T Kawakami, P Tähepôld, A Dumitrescu, C Löwbeer, J Vaage
American Journal of Physiology-Heart and Circulatory Physiology, 2000journals.physiology.org
Acute administration of glucocortiocoids reduces inflammation. Increasing knowledge of the
mechanisms of action indicate that pretreatment with glucocorticoids could have organ-
protective effects. We investigated whether pretreatment with methylprednisolone (MP)
protected the heart against ischemia-reperfusion dysfunction, and we hypothetized that this
protection might be due to induction of the cardioprotective heat shock protein 72 (HSP72).
Rats were given vehicle or MP-40 mg/kg im as a double injection starting either 24 or 120 h …
Acute administration of glucocortiocoids reduces inflammation. Increasing knowledge of the mechanisms of action indicate that pretreatment with glucocorticoids could have organ-protective effects. We investigated whether pretreatment with methylprednisolone (MP) protected the heart against ischemia-reperfusion dysfunction, and we hypothetized that this protection might be due to induction of the cardioprotective heat shock protein 72 (HSP72). Rats were given vehicle or MP-40 mg/kg im as a double injection starting either 24 or 120 h (5 days) before their hearts were excised for Langendorff perfusion (n = 6–11 hearts in each group). MP improved left ventricular function and coronary flow during reperfusion after 30 min of global ischemia and reduced infarct size. Cardiac HSP72 gradually increased in a 24-h time course after MP treatment, and the increase was sustained 5 days afterward (immunoblotting). HSP72 mRNA was either reduced or unchanged, indicating a posttranscriptional regulation. Pretreatment with hydrocortisone or dexamethasone (n = 7–8 hearts of each) similarily increased cardiac HSP72 24 h afterward. This paper demonstrates that glucocorticoids increase cardiac HSP72 and protect organ function against ischemia-reperfusion injury.
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