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A functional role of the cyclin-dependent kinase inhibitor 1 (p21(WAF1/CIP1)) for neuronal preconditioning.

ABSTRACT: Hypoxic preconditioning is thought to rely on gene products regulated by hypoxia-inducible factor (HIF)-1. Here, we show that the HIF-1 target gene cyclin-dependent kinase inhibitor 1, p21(WAF1/CIP1), is essential for neuroprotection by hypoxic/aglycemic or erythropoietin preconditioning using wild-type and p21(WAF1/CIP1)-deficient neurons. Furthermore, overexpression of wild-type p21(WAF1/CIP1) or phospho-mutants significantly increased cell death after hypoxia/aglycemia. Moreover, deferoxamine-induced endogenous tolerance did not involve p21(WAF1/CIP1) expression in cortical neurons. Our data suggest that balanced expression and potentially posttranslational regulation of p21(WAF1/CIP1) is required for hypoxic preconditioning.

SUBMITTER: Mergenthaler P

PROVIDER: S-EPMC3587824 | biostudies-other | 2013 Mar

REPOSITORIES: biostudies-other

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A functional role of the cyclin-dependent kinase inhibitor 1 (p21(WAF1/CIP1)) for neuronal preconditioning.

Mergenthaler Philipp P Muselmann Claudia C Sünwoldt Juliane J Isaev Nickolay K NK Wieloch Tadeusz T Dirnagl Ulrich U Meisel Andreas A Ruscher Karsten K

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20130109 3

Hypoxic preconditioning is thought to rely on gene products regulated by hypoxia-inducible factor (HIF)-1. Here, we show that the HIF-1 target gene cyclin-dependent kinase inhibitor 1, p21(WAF1/CIP1), is essential for neuroprotection by hypoxic/aglycemic or erythropoietin preconditioning using wild-type and p21(WAF1/CIP1)-deficient neurons. Furthermore, overexpression of wild-type p21(WAF1/CIP1) or phospho-mutants significantly increased cell death after hypoxia/aglycemia. Moreover, deferoxamine ...[more]

PMID: 23299246

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