Estudio de los efectos de los extractos de punica granatum y theobroma cacao sobre un modelo de fotocarcinogénesis en ratones SKH-1

Resumen

Introduction: Non-melanoma skin cancer (NMSC) has a high and increasing incidence all over the world. Solar radiation is the main aetiology for humans. Although most research into photocarcinogenesis uses UVB as a source of radiation, UVA is also carcinogenic in long term. Objectives: Pomegranate (PGE) and cocoa (CE) extracts have been used for medicinal purposes for time immemorial. Recently, it has been claimed that some of their properties may be an effective preventative measure against photocarcinogenesis and photoaging, but to date in vivo models have not been tested using RUVA, the objective of the present work. Materials and methods: We used 27 female SKH-1 / CRL mice, which were divided into three groups: Group 1 (irradiated control, n = 9), Group 2 (irradiated mice treated with pomegranate extract, n = 9) and Group 3 (irradiated treated mice with cocoa extract, n = 9). All animals were irradiated with the Type HB 554/01 / A cosmetic tanning lamp that emits 98.6% of UVA and 1.4% UVB) 3 times a week, for one hour, with a total of 80 sessions A macroscopic study was performed with the measurement of lesion areas by image analysis, as well as a microscopic study of the dorsal part of the skin of animals with Hematoxylin-Eosin to determine the type and severity of the lesions, as well as the immunohistochemical study with PCNA, p53, MMP-9 and TIMP-1 markers. Results: A lower incidence of lesions was observed in SKH-1 mice treated with PGE (p<0.001), and lower incidence of invasive squamous carcinoma in both treatment groups (p<0.001 for PGE and p<0.05 for CE); the PGE group also showed a lower level of cell proliferation than the control group (p<0.001). Significantly greater p53 alteration was observed in the control group than the treatment groups (p<0.001 for PGE and p=0.05 for CE). No significant differences were found in relation to TIMP-1 and MMP-9. Conclusions: Taken together, the results suggest that oral feeding of PGE and CE to SKH-1 mice affords substantial protection against the adverse effects of RUVA, especially PGE.