Malignant melanoma is the most aggressive type of skin cancer, and due to the numerous limitations of current treatment methods, there is an urgent need to develop novel approaches for both the prevention and treatment of malignant melanoma, with research-oriented bioactive substances representing a notable first step. The current study decided to expand on previous rhodoxanthin research by investigating the possible anti-tumor effect as well as the effect on the antioxidant status in the case of murine melanoma in an experimental model. The 21-day study was carried out on female C57BL/6J mice. On the first day of the experiment, they were subcutaneously inoculated with 106 B16F10 cells and were given rhodoxanthin orally until the end of the study. Rhodoxanthin supplementation significantly reduced tumor growth (42.18%) and weight (15.74%). Furthermore, the epidermal growth factor (EGF) activity was reduced and the concentration of 8-OHdG dropped in the treated melanoma-bearing mice compared to the untreated ones, demonstrating the role of rhodoxanthin in slowing tumor growth, one of the mechanisms being the reduction of EGF level and the decrease of DNA oxidation. The administration of rhodoxanthin determined variations in antioxidant enzymes, both at the plasma level and at the tissue level.

Nowadays, 3R (replacement, reduction, refinement) concept lies in the core of laboratory animals science, one of the most important refinement strategies being the pain control. Rat Grimace Scale (RGS) is an actual and effective method used to assess pain in laboratory animals. The purpose of this study was to find the most effective post surgery analgesic protocol, by grading the changes in the animal's facial expression. In the present study we used 5 Wistar rats, one as control and four animals subjected to ovariectomy. Tramadol was administrated subcutaneously as it follows: 1 rat in pre-surgery dose of 25 mg/kg, 2 rats in post-surgery a dose of 25 mg/kg and respectively 50 mg/kg. The evaluation of pain was done across at the time 0, 2, 4 and 6 hours post-surgery using the scores of 0, 1 and 2, 0 representing the absence of pain, 1 a moderate level of pain and 2 a high level of pain. The results of the study revealed that the spayed rat without Tramadol presented the highest level of pain (1.25 -1.75). The pre-surgery analgesia enhanced the narcosis effect, but analgesia had a short term effect, with a moderate to high level of pain (1 -1.5). To the animal treated with a dose of 25 mg/kg post-surgery, a moderate pain level was observed (0.5 -1.25) and to the animal with the highest dose an optimal analgesia was determined (0.25). The expected analgesic effect was put forward by the 50 mg/kg dose of Tramadol and the RGS method was found to be suitable for the assessment of animal suffering in surgical experimental procedures.