title: Saponins from Tribulus terrestris L. protect human keratinocytes from UVB-induced damage.
abstract: Chronic exposure to solar UVB radiation damages skin, increasing the risk to develop cancer. Hence the identification of compounds with a photoprotective efficacy is essential. This study examined the role of saponins derived from Tribulus terrestris L. (TT) on the modulation of apoptosis in normal human keratinocytes (NHEK) exposed to physiological doses of UVB and to evaluate their antitumoral properties. In NHEK, TT saponins attenuate UVB-induced programmed cell death through inhibition of intrinsic apoptotic pathway. In squamous cell carcinomas (SCC) TT saponins do not make the malignant keratinocytes more resistant to UVB and determine an enhanced apoptotic response. The photoprotective effect of TT saponins is tightly correlated to the enhancement of NER genes expression and the block of UVB-mediated NF-κB activation. Collectively, our study shows experimental evidence that TT has a preventive efficacy against UVB-induced carcinogenesis and the molecular knowledge on the mechanisms through which TT saponins regulate cell death suggests great potential for TT to be developed into a new medicine for cancer patients.
authors.affiliation: Department of Basic Medical Sciences, Section of Human Anatomy and Histology, University of Bari, Bari, Italy. margherita.sisto@uniba.it
authors.forename: Margherita
authors.initials: M
authors.lastname: Sisto
authors.forename: Sabrina
authors.initials: S
authors.lastname: Lisi
authors.forename: Massimo
authors.initials: M
authors.lastname: D'Amore
authors.forename: Raffaella
authors.initials: R
authors.lastname: De Lucro
authors.forename: Davide
authors.initials: D
authors.lastname: Carati
authors.forename: Donatello
authors.initials: D
authors.lastname: Castellana
authors.forename: Velia
authors.initials: V
authors.lastname: La Pesa
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Zuccarello
authors.forename: Dario D
authors.initials: DD
authors.lastname: Lofrumento
mesh_terms: D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D004260:DNA Repair / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D018450:Disease Progression; D000078404:Epidermal Cells; D005786:Gene Expression Regulation / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D016328:NF-kappa B / Q000378:metabolism; D011740:Pyrimidine Dimers / Q000378:metabolism; D012503:Saponins / Q000302:isolation & purification / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects / Q000528:radiation effects; D012878:Skin Neoplasms / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D032444:Tribulus / Q000737:chemistry*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D000970:Antineoplastic Agents; D016328:NF-kappa B; D011740:Pyrimidine Dimers; D012503:Saponins