Supervisors info:
Ράλλης Μιχαήλ, Επίκουρος Καθηγητής Τομέα Φαρμακευτικής Τεχνολογίας, Τμήμα Φαρμακευτικής, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Summary:
The effect of ultraviolet radiation on normal skin and carcinogenic activity has been extensively studied, while there is no corresponding studies for diabetic skin.
The purpose of the experiment was to cause squamous cell carcinoma in diabetic mice with diabetes type I and type II.
The induction of type I diabetes was mediated by streptozotocin. For the first time, four types of hairless male mice (SKH-hr-1 white, SKH-hr-2, SKH-hr-2 coffee and SKH-hr-2 + APOE) were tested to induce diabetes type II with two different protocols. The first protocol included administration of streptozotocin intraperitoneally in combination with a high-fat diet and sugars to create insulin resistance through metabolic syndrome, while the second one, administration of nicotinamide and streptozotocin intraperitoneally for partial loss of β-pancreatic cells. Protocols were evaluated by measuring the levels of glucose and insulin in the blood of the mice.
Based on the results of inducing diabetes type II, the SKH-hr-2 type with the nicotinamide and streptozotocin protocol was selected as a suitable model for carcinogenesis in normal and diabetic mice. Photocarcinogenesis was achieved with a high dose of ultraviolet radiation (3.5 M.E.D.) for 6 months 3 times a week. Blood glucose, hydration, loss of water, elasticity, skin thickness, body weight, sebum, erythema and melanin were measured. The clinical picture was evaluated, photographs were taken with professional camera, with dermatoscope and by using a special dermatological camera (Antera3D) and histopathological study was also performed. In addition, the levels of hydrophilic antioxidant molecules (uric and ascorbic acid) in the stratum corneum was evaluated by using the technique of strippings.
Normal irradiated mice all acquired squamous cell carcinoma in situ, and some ulcers and actinic keratoses, while diabetic irradiated mice did not give any evidence of squamous cell carcinoma or cell atypia and dysplasia. The irradiated normal skin was found to be more dehydrated, more fattened than the corresponding diabetic. Ultraviolet radiation significantly reduced the hydrophilic antioxidants in the skin of irradiated normal skin, compared to those of diabetics.
The results showed the protection of diabetes against ultraviolet radiation. Moreover, studies are needed to approach and verify the mechanisms to which the above observations are based.
Keywords:
Type I diabetes, Type II diabetes, Skin cancer, Squamous cell carcinoma, Ultraviolet radiation, Skin Antioxidants, Streptozotocin
