Introduction : Excessive UV radiation on the skin can cause DNA damage that triggers the inflammatory
response and immunosuppression. This study aimed to verify whether the bixin lotion has the effect to
offer protection against inflammation and immunosuppression due to acute UVB irradiation in shaved
BALB /c mice.
Methods : Protection against inflammation and immunosuppression, respectively were studied in 4
groups of mice receiving the topical application of base lotion (control); bixin lotion doses of 0.5; 2.5 and
125 mg, 10 days prior to and during the UVB irradiation. Inflammation was induced by UVB irradiation
360 mJ/cm2 once a day for 3 consecutive days, whereas immunosuppression was induced for 5
consecutive days. The inflammatory response was measured as an increase in middorsal skinfold
thickness at the peak response. The immune response was measured as the contact hypersensitivity
(CHS) response to oxasolon sensitization.
Results : The results indicated that in all concentrations used, bixin lotion significantly decreased the
middorsal skinfold thickness at 72 hours after UVB radiation (p <0.05) compared to the control, but there
was no significant difference between couples of the dose of bixin. Bixin lotion was also able to restore
the suppression of CHS from 34.22% in the control group to 11.4; 0.5 and -67% (p <0.05) at doses of
0.5; 2.5 and 125 mg respectively.
Conclusion : Bixin lotion had potential to reduce the inflammatory edema reaction and the suppression
of CHS of mice induced by UVB radiation.
Keywords: Bixa orellana L., photoprotection, inflammation, immunosuppression, UVB radiation