Antioxidative properties of brown algae polyphenolics and their perspectives as chemopreventive agents against vascular risk factors.
Several polyphenolic compounds and complex mixtures were isolated from brown algae species. The 1,1-diphenyl-2-picryhydarzyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP) of these compounds were evaluated to determine their physiological usefulness as antioxidants for vascular protection. The antioxidative protection of low-density lipoprotein (LDL) was also evaluated and compared with that of catechin, because the generation of oxidized LDL is one of the most active and specific risk factors contributing to atherogenesis. Oral administration to rats of a commercially available sample (VNP) containing 30% of these polyphenolic compounds and 70% dietary fiber revealed that the serum reducing capacity measured in terms of FRAP value was significantly elevated 30 min after the treatment, but declined rather quickly thereafter, indicating the good oral absorption of the compounds and their fast binding to the lumenal surface of the blood vessels. An eight-week, human, clinical trial (n=31) of VNP showed significant improvement in erectile function measured by IIEF (international index of erectile function) score. These results collectively demonstrated the usefulness of these polyphenolic compounds as fundamental chemopreventive agents against vascular risk factors originating from oxidative stress.
Laboratory of Aging and Degenerative Diseases, Hanbat National University, Dukmyung-Dong, Yuseong-Gu, Daejeon 305-719, Korea.
Keejung
K
Kang
Yongju
Y
Park
Hye Jeong
HJ
Hwang
Seong Ho
SH
Kim
Jeong Gu
JG
Lee
Hyeon-Cheol
HC
Shin
D000818:Animals; D000975:Antioxidants / Q000737:chemistry*; D001713:Biphenyl Compounds; D005591:Chemical Fractionation; D018890:Chemoprevention; D005419:Flavonoids / Q000737:chemistry* / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007783:Lactones / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000037:antagonists & inhibitors / Q000378:metabolism; D008297:Male; D009835:Oligochaeta / Q000378:metabolism; D010410:Penile Erection / Q000187:drug effects* / Q000502:physiology*; D000459:Phaeophyceae / Q000737:chemistry* / Q000378:metabolism*; D010636:Phenols / Q000737:chemistry* / Q000494:pharmacology*; D010851:Picrates / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D059808:Polyphenols; D051381:Rats; D017207:Rats, Sprague-Dawley; D012307:Risk Factors; D013997:Time Factors; D014652:Vascular Diseases / Q000517:prevention & control*
D000975:Antioxidants; D001713:Biphenyl Compounds; D005419:Flavonoids; D016166:Free Radical Scavengers; D007783:Lactones; D008077:Lipoproteins, LDL; D010636:Phenols; D010851:Picrates; D010936:Plant Extracts; D059808:Polyphenols; C086784:ecklonialactone A; C004931:1,1-diphenyl-2-picrylhydrazyl