Fig. 2. Proposed model of how protein kinase C beta activation causes adipose dysfunction by initiating a mitochondrial axis involving 66 kDa isoform of mammalian ShcA gene, leading to adipocyte hypertrophy, oxidative stress, and
inflammation. protein kinase C beta activation by high-fat diet-induced or genetic obesity initiates a signaling cascade causing mitochondrial dysfunction, which results in downregulation of autophagy and
contributes to obesity and insulin resistance. Dysfunctional mitochondria may create a vicious cycle of protein kinase C beta activation, further jeopardizing mitochondrial function. Mitochondrial
dysfunction can activate protein kinase C beta in two ways: (i) by interfering with oxidation of fatty acyl-CoA and consequently causing accumulation of intracellular lipid and diacylglycerol,
and (ii) by generation of reactive oxygen species that activate protein kinase C beta. Such mechanisms are capable of causing or maintaining protein kinase C beta activation and adipose tissue dysfunction
in obesity, potentially linking obesity to associated disorders.