A 24-amino acid leader peptide of a new human recombinant manganese superoxide dismutase can enter cells and carry molecules. Here, we demonstrated that six of the 24 amino acids penetrate cells through a particular gate represented by a specific amino acid sequence of the oestrogen receptor (ER). We analysed the internalization of the synthetic hexapeptide and the cytotoxic activity of the hexapeptide conjugated to cisplatin on a cell line panel. In most cell lines, the hexapeptide delivered an amount of cisplatin that was 2 to 8 times greater than that released by cisplatin when the drug was used alone. This increased delivery increases the therapeutic index of cisplatin and reduces side effects caused by a high dosage or long-term treatment times. We may consider this hexapeptide a new molecular carrier to deliver molecules with therapeutic activity into ER+ cells for diagnostic purposes and clinical or immune therapy.

In humans red blood cells live on average of 120 days. Senescent erythrocytes are removed from circulation by macrophages; this process, called erythrophagocytosis (EPC), takes place mainly in the liver but also in the bone marrow. We studied this process in loggerhead turtles Caretta caretta, inhabiting the Mediterranean Sea. Leukocytes of reptiles include heterophils, eosinophils, lymphocytes, basophils, thrombocytes, monocytes, and of these heterophils and monocytes represent the main phagocytic cells. The aim of this study was to investigate the blood of C. caretta specimens and to observe, in the blood smears, heterophils phagocytizing erythrocytes. The phagocytizing cells were also identified by cytochemical reactions. Furthermore some examples of tear-shaped erythrocytes (dacrocytes) were observed. A mechanism presuming a causative link between erythrophagocytosis and teardrop-erythrocyte detection have been proposed to explain this seemingly general pattern of all specimens both wild and housed.

Physiological processes, as aerobic metabolism and inflammatory response, generate reactive oxygen species (ROS) that may induce cellular injury when their amount is increased and antioxidant defense mechanisms are overwhelmed. Also, ROS are generated following UV skin irradiation able to deplete the natural antioxidant defenses in the skin. The increase in exposure to UV may lead to photoaging and precancerous skin lesions (actinic keratosis). New antioxidant strategies in the prevention and therapy of skin lesions are urgently needed. In this study, we evaluated the antioxidant efficacy of a recombinant form of human manganese superoxide dismutase able to inhibit reactive oxygen species production in some patients affected by severe photoaging and actinic keratosis.