Angiogenin is a protein crucial in angiogenesis, and it is overexpressed in many cancers and downregulated in neurodegenerative diseases, respectively. The protein interaction with actin, through the loop encompassing the 6-68 residues, is an essential step in the cellular cytoskeleton reorganization. This, in turn, influences the cell proliferation and migration processes. Angiogenin (ANG) is a secretory ribonuclease that promotes the proliferation of endothelial cells, leading to angiogenesis. This function relies on its ribonucleolytic activity, which is low for simple RNA substrates. Upon entry into the cytosol, ANG is sequestered by the ribonuclease inhibitor protein (RNH1). ANG is a potent cytotoxin for RNH1-knockout HeLa cells, belying its inefficiency as a nonspecific catalyst. The toxicity does, however, rely on the ribonucleolytic activity of ANG and a cytosolic localization, which lead to the accumulation of particular tRNA fragments (tRFs), such as tRF-5 Gly-GCC. These up-regulated tRFs are highly cytotoxic at physiological concentrations. Although ANG is well-known for its promotion of cell growth. Angiogenin and osteoprotegerin are triceps specific myokines with beta-cell protective actions against proinflammatory cytokines. Angiogenin and EPCs are modulated by rehabilitation after cerebral ischemia, suggesting that both angiogenin and EPCs could serve as biomarkers of improvement during rehabilitation or future therapeutic targets.