The Effect of 1, 25-Dihydroxyvitamin D3 on Dopaminergic Neurons and Microglial Activation in Parkinsonian Rat Model Induced by 6-Hydroxydopamine.
- Author:
Seon Young RYU
1
;
Joong Seok KIM
;
Young Bin CHOI
;
Si Ryung HAN
;
Jeong Wook PARK
;
Sung Kyung PARK
;
Yeong In KIM
Author Information
1. Department of Neurology, The Catholic University of Korea College of Medicine, Seoul, Korea. nuyikim@cmc.cuk.ac.kr
- Publication Type:Original Article
- Keywords:
Vitamin D3;
Microglia;
Parkinson's disease;
6-hydroxydopamine
- MeSH:
Adult;
Animals;
Cholecalciferol;
Dopaminergic Neurons*;
Ethanol;
Humans;
Immunohistochemistry;
Male;
Medial Forebrain Bundle;
Microglia;
Models, Animal*;
Nerve Growth Factors;
Neurodegenerative Diseases;
Neurons;
Neuroprotective Agents;
Oxidopamine*;
Parkinson Disease;
Rats*;
Rats, Sprague-Dawley;
Substantia Nigra;
Tyrosine 3-Monooxygenase
- From:Journal of the Korean Neurological Association
2005;23(3):368-373
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Recent studies have shown increasing evidence for microglial activation in neuronal degeneration in Parkinson's disease (PD), although the cause of PD remains unclear. Recent studies have also shown that 1alpha, 25-dihydroxyvitamin D3 (vitamin D3) exert neuroprotective effects by inducing an increased expression of neurotrophic factors, suggesting the possibility of vitamin D3 for the treatment of PD and other neurodegenerative diseases. The purpose of this study was to investigate the effect of vitamin D3 on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity and microglial activation in adult rats. METHODS: Adult male Sprague-Dawley rats were subcutaneously injected with vitamin D3 or 0.1% ethanol for seven consecutive days and then infused unilaterally with 6-OHDA in the medial forebrain bundle. After 7 days of injection with 6-OHDA, the substantia nigra was examined by immunohistochemistry. RESULTS: The number of tyrosine hydroxylase (TH)-positive neurons in the lesioned substantia nigra pars compacta of vitamin D3 and ethanol groups was 84.8 +/- 18.84 and 52.6 +/- 13.23, respectively, fewer than that of the contralateral side (122.35 +/- 9.79 and 123.81 +/- 12.11, respectively) (P<0.05). The vitamin D3 group showed significantly higher numbers of the TH-positive neurons than that of the ethanol group (P<0.05). CD11b-positive microglial immunoreactivity was stronger in the lesion side than that of the normal side, and it was much weaker in the vitamin D3 group than that of the ethanol group (P<0.05). CONCLUSIONS: These results indicate that vitamin D3 protects dopaminergic neurons from the neuronal injury induced by 6-OHDA, possibly by the mechanism involving microglial activation.
