HSPB8 and cardiomyopathy: However, TG mice overexpressing HSPB8 K141N in cardiac tissue show aggregating HSPB8 and mitochondrial dysfunction in cardiomyocytes and develop signs of cardiomyopathy at the age of 6 months (Sanbe et al., 2013), while KO mice show cardiac defects with aging (Wu et al., 2021).