Autophagy and cardiovascular aging

Figures & data

Figure 1. Stages involved in the formation of autolysosome from phagophore for various cellular components.

Figure 2. Signaling pathways regulating the activity of mTORC1. Growth factor (such as insulin and IGF1) stimulation activates Akt which inactivates TSC2 via phosphorylation leading to the conversion of Rheb-GTP to Reb-GD preventing inhibition of mTORC1. On the other hand, low levels of ATP can result in the activation of AMPK which can inhibit mTORC1. Activated mTORC1 can induce translation of mRNA via the phosphorylation of 4E-BP1 and p70S6 kinase. mTORC1 also results in suppression of autophagy.

Table 1. Upregulation or downregulation of autophagy in the heart under various pathophysiological conditions

	Autophagy
Ischemia	↑	Protective
Reperfusion	↑↑	Detrimental
Compensatory hypertrophy	↓	Adaptive mechanism
Decompensatory hypertrophy	↑↑	Detrimental (cell death)
Starvation	↑	Protective, survival