“…OPIOIDS D-Ala(2)-D-Leu(5)-enkephalin (DADLE) is a synthetic hypometabolizing opioid (Oeltgen et al, 1988) of potential biomedical interest (Malatesta et al, 2007). In fact, DADLE is able to significantly prolong the preservation of explanted organs (Oeltgen et al, 1996;Bolling et al, 1997;Su, 2000;Inuo et al, 2007;Tisherman et al, 2013), to improve cardioprotection (Romano et al, 2004;Yao et al, 2007;Forster et al, 2007; and neuroprotection (Borlongan et al, 2004;Su et al, 2007;Wang et al, 2011;Arrich et al, 2012) under ischemic conditions, and to act as anti-tumour agent (Fichna and Janecka, 2004;Debruyne et al, 2010;Tsai et al, 2010).…”