In 2006, Ding et al. examined the chemopreventive and chemotherapeutic activity of cyanidin-3-glucoside (C3G), a key active ingredient in blackberry. C3G was shown to scavenge UVB-induced hydroxyl and superoxide radicals in cultured JB6 cells. The investigators observed reductions in the number of nonmalignant and malignant skin tumors per mouse induced by TPA in 7,12-dimethylbenz[a]anthracene-initiated mouse skin. In addition, UVB- and TPA-induced transactivation of NF-kappaB and AP-1 and expression of cyclooxygenase-2 and tumor necrosis factor–alpha were suppressed by the pretreatment with C3G of JB6 cells. The researchers suggested that the inhibition of MAPK activity may be important in mediating such effects. TPA-induced neoplastic transformation in JB6 cells was also hindered via C3G pretreatment. Further, C3G suppressed proliferation of the human lung carcinoma cell line A549, diminished the size of A549 tumor xenograft growth, and significantly limited metastasis in nude mice. The investigators concluded that C3G, an important constituent of blackberry, displays significant anticancer activity by dint of its capacity to scavenge free radicals. As such, they suggested that this blackberry derivative, which exhibits scant cytotoxicity to healthy tissue, warrants additional study as a preventive and therapeutic agent in human cancers (J. Biol. Chem. 2006;281:17359-68).
Conclusion
The most recent evidence suggests that blackberry warrants attention for medical applications, including dermatology. In fact, in a small (n = 33) single-center, open-label study led by the author, significant improvement in most metrics of photoaged skin was observed after the use of a day and night regimen containing blackberry leaf extract, dill extract, and Zn-Cu(II) bi-mineral complex in patients with mild to moderate photodamage. (Baumann LS, Figueras KA, Bell M, Flitter CJ. Assessing the efficacy and tolerance of a day and night regimen containing blackberry leaf extract, dill extract, and Cu-Zinc bi-mineral complex in subjects with mild to moderate photoaged skin. Unpublished results.) It remains to be seen if and when blackberry extract alone may be harnessed for dermatologic indications, but present data are promising, and justify continued study.
Dr. Baumann is in private practice in Miami Beach. She did not disclose any conflicts of interest. To respond to this column, or to suggest topics for future columns, write to her at sknews@frontlinemedcom.com.