MTOR and hypertensive heart disease: In hypertensive heart disease, factor-alpha-related protein 9 (CTRP9) decreased phosphorylation levels of phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), and mammalian target of rapamycin (mTOR) proteins, which led to reduced vascular endothelial cell injury (Pan et al., 2022).