Activation of Ca2+/
calmodulin-dependent protein kinase (
CaMKII) has been proved to play a vital role in
cardiovascular diseases. Receptor-interaction
protein kinase 3- (RIPK3-) mediated necroptosis has crucially participated in cardiac dysfunction. The study is aimed at investigating the effect as well as the mechanism of
CaMKII activation and necroptosis on
diabetic cardiomyopathy (DCM). Wild-type (WT) and the RIPK3 gene knockout (RIPK3-/-) mice were intraperitoneally injected with 60 mg/kg/d
streptozotocin (STZ) for 5 consecutive days. After 12 w of feeding, 100 μL recombinant adenovirus
solution carrying inhibitor 1 of
protein phosphatase 1 (I1PP1) gene was injected into the caudal vein of mice. Echocardiography, myocardial injury,
CaMKII activity, necroptosis, RIPK1 expression, mixed lineage
kinase domain-like
protein (MLKL) phosphorylation, and mitochondrial ultrastructure were measured. The results showed that cardiac dysfunction,
CaMKII activation, and necroptosis were aggravated in
streptozotocin- (STZ-) stimulated mice, as well as in (Lepr) KO/KO (db/db) mice. RIPK3 deficiency alleviated cardiac dysfunction,
CaMKII activation, and necroptosis in DCM. Furthermore, I1PP1 overexpression reversed cardiac dysfunction, myocardial injury and necroptosis augment, and
CaMKII activity enhancement in WT mice with DCM but not in RIPK3-/- mice with DCM. The present study demonstrated that
CaMKII activation and necroptosis augment in DCM via a RIPK3-dependent manner, which may provide therapeutic strategies for DCM.