INS and early-onset autosomal dominant Alzheimer disease: Previous studies related to the insulin signaling pathway have focused on tissues and other aspects.[14–16] Chen Yanxing et al studied insulin signaling in brain tissues and concluded that insulin signaling pathway plays an important role in Alzheimer disease.[17] Some researchers suggested that defective protein kinase A (PKA) activation in diabetic cardiomyocytes, partly mediated by lack of insulin signaling, lead to abnormal activation of primary metabolic regulators.