Dendropanax morbifera Léveille extract ameliorates cadmium-induced impairment in memory and hippocampal neurogenesis in rats.
BACKGROUND
Cadmium leads to learning and memory impairment. Dendropanax morbifera Léveille stem extract (DMS) reduces cadmium-induced oxidative stress in the hippocampus. We investigated the effects of DMS on cadmium-induced impairments in memory in rats.


METHODS
Cadmium (2 mg/kg), with or without DMS (100 mg/kg), was orally administered to 7-week-old Sprague-Dawley rats for 28 days. Galantamine (5 mg/kg), an acetylcholinesterase inhibitor, was intraperitoneally administered as a positive control. A novel-object recognition test was conducted 2 h after the final administration. Cell proliferation and neuroblast differentiation were assessed by immunohistochemistry for Ki67 and doublecortin, respectively. Acetylcholinesterase activity in the synaptosomes of the hippocampus was also measured based on the formation of 5,5'-dithio-bis-acid nitrobenzoic acid.


RESULTS
An increase in the preferential exploration time of new objects was observed in both vehicle-treated and cadmium-treated rats. In addition, DMS administration increased cell proliferation and neuroblast differentiation in the dentate gyrus of vehicle-treated and cadmium-treated rats. Acetylcholinesterase activity in the hippocampal synaptosomes was also significantly higher in the DMS-treated group than in the vehicle-treated group. The effect of DMS on cadmium-induced memory impairment and cell proliferation in the hippocampus was comparable to that of galantamine.


CONCLUSIONS
These results suggest that DMS ameliorates cadmium-induced memory impairment via increase in cell proliferation, neuroblast differentiation, and acetylcholinesterase activity in the hippocampus. The consumption of DMS may reduce cadmium-induced neurotoxicity in animals or humans.
Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea.
Woosuk
W
Kim
Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Kangneung-Wonju National University, Gangneung, 25457, South Korea.
Hee Sun
HS
Yim
Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea.
Dae Young
DY
Yoo
Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea.
Hyo Young
HY
Jung
Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea.
Jong Whi
JW
Kim
Department of Anatomy, College of Veterinary Medicine, Kangwon National University, Chuncheon, 24341, South Korea.
Jung Hoon
JH
Choi
Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea.
Yeo Sung
YS
Yoon
Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Kangneung-Wonju National University, Gangneung, 25457, South Korea.
Dae Won
DW
Kim
Department of Anatomy and Cell Biology, College of Veterinary Medicine, and Research Institute for Veterinary Science, Seoul National University, Seoul, 08826, South Korea. vetmed2@snu.ac.kr.|Department of Anatomy and Cell Biology, College of Veterinary Medicine, Seoul National University, Seoul, 08826, South Korea. vetmed2@snu.ac.kr.
In Koo
http://orcid.org/0000-0002-0533-4638
IK
Hwang
D000818:Animals; D027481:Araliaceae / Q000737:chemistry*; D002104:Cadmium / Q000633:toxicity*; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D000089662:Doublecortin Protein; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects; D008569:Memory Disorders / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D055495:Neurogenesis / Q000187:drug effects*; D009474:Neurons / Q000166:cytology / Q000187:drug effects; D010936:Plant Extracts / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley
C000714848:Dcx protein, rat; D000089662:Doublecortin Protein; D010936:Plant Extracts; D002104:Cadmium
Acetylcholinesterase; Cadmium; Dendropanax morbifera extract; Memory; Neurogenesis