Pdk4, or pyruvate dehydrogenase kinase 4, is a crucial mitochondrial matrix enzyme involved in cellular energy regulation. It is associated with multiple metabolic pathways, such as glycolysis and mitochondrial respiration. Pdk4 plays a significant role in various biological processes and diseases, and genetic models like KO/CKO mouse models are valuable for studying its functions [3].

In obesity, Pdk4 interacts with and stabilizes a complex at the mitochondria-associated endoplasmic reticulum membrane, augmenting its formation and suppressing insulin signaling. Pdk4-/-mice exhibit reduced membrane formation and are protected against diet-induced skeletal muscle insulin resistance [1].

In vascular calcification, knocking down Pdk4 restores autophagic activity and abrogates the Warburg-like metabolic reprogramming of vascular smooth muscle cells, thereby preventing calcification [3].

In ferroptosis resistance, PDK4 inhibits ferroptosis by blocking pyruvate oxidation, and inhibiting PDK4 enhances the anticancer activity of system xc-inhibitors in vitro and in preclinical mouse models [2].

Also, in diabetic wound healing, overexpression of Pdk4 in STZ-induced diabetic mice and human dermal fibroblasts accelerates wound healing and improves the senescent phenotype via enhancing glycolysis and regulating YAP and JNK pathways [4].

In conclusion, Pdk4 is essential in regulating cellular energy metabolism and has a profound impact on multiple disease conditions. Studies using KO/CKO mouse models have revealed its role in obesity-related insulin resistance, vascular calcification, ferroptosis resistance, and diabetic wound healing, highlighting its potential as a therapeutic target in these disease areas.