Neuroprotective effects of Polygonum multiflorum on nigrostriatal dopaminergic degeneration induced by paraquat and maneb in mice.
The neuroprotective effects of Polygonum multiflorum extract (PME) and its two fractions, ethanol-soluble PME (PME-I) and -insoluble PME (PME-II), on the degeneration of nigrostriatal dopaminergic neurons induced by a combination of paraquat and maneb (PQMB) were investigated in male C57BL/6 mice. The mice were treated twice a week for 6 weeks with intraperitoneal injections of PQMB. This combination caused a reduction of spontaneous locomotor activity, motor incoordination, and declines of dopamine level in the striatum and tyrosine hydroxylase-positive neurons in the substantia nigra. Administration of PME and PME-I once daily for 47 days during 6 weeks of PQMB treatment and last 8 days after PQMB significantly attenuated the impairment of behavioral performance and the decrease in striatal dopamine level and substantia nigral tyrosine hydroxylase-positive neurons in the PQMB-treated animals, whereas the administration of PME-II had no effect on these behavioral, neurochemical and histological indices. The present findings suggest that PME has a beneficial influence on parkinsonism induced by PQMB and that the effects of PME are attributable to some substance(s) included in the ethanol-soluble fraction of PME (PME-I).
Li
Xia
X
Division of Natural Products Chemistry, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan.
Matsumoto
Kinzo
K
Murakami
Yukihisa
Y
Tezuka
Yasuhiro
Y
Wu
Yingliang
Y
Kadota
Shigetoshi
S
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D000978:Antiparkinson Agents / Q000627:therapeutic use; D002851:Chromatography, High Pressure Liquid; D004298:Dopamine / Q000378:metabolism / Q000502:physiology*; D005659:Fungicides, Industrial / Q000633:toxicity*; D006540:Herbicides / Q000633:toxicity*; D007150:Immunohistochemistry; D007980:Levodopa / Q000627:therapeutic use; D008297:Male; D008344:Maneb / Q000633:toxicity*; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000187:drug effects; D017072:Neostriatum / Q000473:pathology*; D009410:Nerve Degeneration / Q000139:chemically induced / Q000473:pathology* / Q000517:prevention & control*; D018696:Neuroprotective Agents / Q000494:pharmacology*; D010269:Paraquat / Q000633:toxicity*; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000517:prevention & control; D008517:Phytotherapy; D018517:Plant Roots / Q000737:chemistry; D028502:Polygonum / Q000737:chemistry*; D013378:Substantia Nigra / Q000473:pathology*; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
D000978:Antiparkinson Agents; D005659:Fungicides, Industrial; D006540:Herbicides; D018696:Neuroprotective Agents; D015102:3,4-Dihydroxyphenylacetic Acid; D008344:Maneb; D007980:Levodopa; D014446:Tyrosine 3-Monooxygenase; D010269:Paraquat; D004298:Dopamine