The present study assessed comparatively the antioxidant activities of silymarin and its major active component silibinin and their neuroprotective effects against hydrogen peroxide (H2O2)-induced oxidative stress in rat pheochromocytoma PC12 cells. It was found that despite newly prepared silymarin and silibinin solution possessing comparable superoxide anion (O2.–)-scavenging activities, with time the activity of silymarin lowered slightly, but that of silibinin decreased dramatically. Both silymarin and silibinin suppressed H2O2-induced oxidative stress and apoptosis, and the neuroprotective effect of silymarin was overall relatively stronger than that of silibinin. The findings provided clues for future studies on therapeutic potentials of the whole silymarin or purified silibinin for neurodegenerative diseases.
DiM.V., EspositoE. (2003) Biochemical and therapeutic effects of antioxidants in the treatment of Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Current Drug Targets CNS Neurological Disorders, 2, 95–107.
10.
EspositoE., RotilioD., Di MatteoV., Di GiulioC., CacchioM., AlgeriS. (2002) A review of specific dietary antioxidants and the effects on biochemical mechanisms related to neurodegenerative processes. Neurobiology Aging, 23, 719–735.
11.
FloraK., HahnM., RosenH., BennerK. (1998) Milk thistle (Silybum marianum) for the therapy of liver disease. American Journal of Gastroenterology, 93, 139–143.
12.
WellingtonK., JarvisB. (2001) Silymarin: a review of its clinical properties in the management of hepatic disorders. BioDrugs, 15, 465–489.
BorahA., PaulR., ChoudhuryS., ChoudhuryA., BhuyanB., Das TalukdarA., Dutta ChoudhuryM., MohanakumarK.P. (2013) Potential of silymarin against CNS disorders: insight into the pathways and molecular mechanisms of action. CNS Neuroscience Therapy, 19, 847–853.
15.
SinghalN.K., SrivastavaG., PatelD.K., JainS.K., SinghM.P. (2011) Melatonin or silymarin reduces maneb- and paraquat-induced Parkinson's disease phenotype in the mouse. Journal of Pineal Research., 50. 97–109.
16.
KimM.H., KimS.H., YangW.M. (2014) Mechanisms of action of phytochemicals from medicinal herbs in the treatment of Alzheimer's disease. Planta Medica, 80, 1249–1258.
17.
MilićN., MiloševićN., SuvajdžićL., ŽarkovM., AbenavoliL. (2013) New therapeutic potentials of milk thistle (Silybum marianum). Natural Product Communications.8. 1801–1810.
18.
LuP., MamiyaT., LuL.L., MouriA., ZouL., NagaiT., HiramatsuM., IkejimaT., NabeshimaT. (2009) Silibinin prevents amyloid beta peptide-induced memory impairment and oxidative stress in mice. British Journal of Pharmacology, 157, 1270–1277.
19.
MurataN., MurakamiK., OzawaY., KinoshitaN., IrieK., ShirasawaT., ShimizuT. (2010) Silymarin attenuated the amyloid β plaque burden and improved behavioral abnormalities in an Alzheimer's disease mouse model. Bioscience Biotechnology and Biochemistry, 74, 2299–2306.
20.
WesterinkR.H.S., EwingA.G. (2008) The PC12 cell as model for neurosecretion. Acta Physiologica, 192, 273–285.
21.
ShenL., JiH.F. (2012) Vitamin E: supplement versus diet in neurodegenerative diseases. Trends in Molecular Medicine, 18, 443–445.
22.
JiH.F., ShenL. (2014) The multiple pharmaceutical potential of curcumin in Parkinson's disease. CNS Neurological Disorders Drug Targets, 13, 369–373.
23.
JiH.F., LiX.J., ZhangH.Y. (2009) Natural products and drug discovery. Can thousands of years of ancient medical knowledge lead us to new and powerful drug combinations in the fight against cancer and dementia?EMBO Reports, 10, 194–200.
24.
ZhangJ., LuanQ., LiuY., LeeD.Y., WangZ. (2011) A comparison of the diastereoisomers, silybin A and silybin B, on the induction of apoptosis in K562 cells. Natural Product Communications, 6, 1653–1656.
25.
ZhangP., HanG., GaoP., QiaoK., RenY., LiangC., LengB., WuZ. (2015) Protective effect of silymarin against rapamycin-induced apoptosis and proliferation inhibition in endothelial progenitor cells. Natural Product Communications, 10, 263–266.
26.
TangN., WuD., LuY., ChenJ., ZhangB., WuW. (2009) A comparative study on the stability of silybin and that in silymarin in buffers and biological fluids. Drug Metabolism Letters, 3, 115–119.
27.
WilliamsonE.M. (2001) Synergy and other interactions in phytomedicines. Phytomedicine, 8, 401–409.
28.
YaghmaeiP., AzarfarK., DezfulianM., Ebrahim-HabibiA. (2014) Silymarin effect on amyloid-β plaque accumulation and gene expression of APP in an Alzheimer's disease rat model. Daru, 22, 24.
29.
YinF., LiuJ., JiX., WangY., ZidichouskiJ., ZhangJ. (2011) Silibinin: A novel inhibitor of Aβ aggregation. Neurochemistry International, 58, 399–403.
30.
Post-WhiteJ., LadasE.J., KellyK.M. (2007) Advances in the use of milk thistle (Silybum marianum). Integrative Cancer Therapies, 6, 104–109.
31.
LiX. (2012) Improved pyrogallol autoxidation method: a reliable and cheap superoxide-scavenging assay suitable for all antioxidants. Journal of Agricultural Food Chemistry, 60, 6418–6424.
32.
WangH., JosephJ.A. (1999) Quantifying cellular oxidative stress by dichlorofluorescein assay using microplate reader. Free Radical Biology Medicine, 27, 612–616.
