title: Oxyphytosterols as active ingredients in wheat bran suppress human colon cancer cell growth: identification, chemical synthesis, and biological evaluation.
abstract: Consumption of whole grains has been reported to be associated with a lower risk of colorectal cancer. Recent studies illustrated that phytochemicals in wheat bran (WB) may protect against colorectal cancer. There is a growing interest in the phytosterol contents of foods as either intrinsic or added components due to their beneficial health effects. However, little is known whether phytosterols in WB contribute the observed chemopreventative activity of the grain. In the present study, we directly purified and identified four oxyphytosterols 1-4 from sterol-enriched fraction of WB, and also successfully synthesized five sterol oxides 5-8 and 13. Using these nine compounds as references, we outlined a comprehensive profile of steroids in WB using tandem liquid chromatography mass spectrometry with electrospray ionization (LC-ESI/MS(n), n = 2-3) techniques for the first time. Among them, three sterol oxides 13, 14, and 18 are novel compounds, and 14 compounds 3, 4, 6-11, 13, 14, 16, and 18-20 were reported in WB for the first time. Our results on the inhibitory effects of available sterol oxides 1-8 and 13 against the growth of human colon cancer cells HCT-116 and HT-29 showed that compounds 2-8 exerted significant antiproliferative effects, with oxysterol 8 being the most active one in both cells. We further demonstrated that four most active sterol oxides 5-8 could induce cell death through the apoptosis pathway. Our results showed that phytosterols, particularly oxyphytosterols, in WB possess significant antiproliferative properties, and thereby may greatly contribute the observed chemoprevention of the whole grain wheat.
authors: Center for Excellence in Post-Harvest Technologies, North Carolina Research Campus, North Carolina Agricultural and Technical State University , 500 Laureate Way, Kannapolis, North Carolina 28081, United States.
authors: Yingdong
authors: Y
authors: Zhu
authors: Dominique
authors: D
authors: Soroka
authors: Shengmin
authors: S
authors: Sang
mesh_terms: D016588:Anticarcinogenic Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D003110:Colonic Neoplasms / Q000503:physiopathology; D004043:Dietary Fiber / Q000032:analysis*; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D013058:Mass Spectrometry; D015394:Molecular Structure; D010840:Phytosterols / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000138:chemical synthesis* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D016588:Anticarcinogenic Agents; D004043:Dietary Fiber; D010840:Phytosterols; D010936:Plant Extracts
keywords: apoptosis; chemical synthesis; colon cancer; cytotoxicity; sterol oxide; wheat bran