Gene Therapy with Adenoviral GDNF Vector in the Animal Model of Parkinson's Disease / 대한해부학회지

A recombinant adenoviral vector encoding human GDNF gene (Ad -GDNF) was developed to investigate the effect of GDNF gene in 6 -OHDA -induced Parkinson's disease rat. The changes of rotatory behavior and density of TH -immunoreactive axon terminals and number of cell bodies were observed by the GDNF expression. Adult male Sprague -Dawley rats were used. Parkinson's disease (PD) rat models were prepared by the injection of 6 -OHDA into the striatum. After 1 week, the animals showing apomorphine -induced rotatory behavior above 7 turns/ min were defined as PD rat model. Ad -GDNF was injected into the striatum of animal model and tested the apomorphine -induced rotatory behavior at 1 week after injection. These animals were perfused with Zamboni fixative to investigate the morphological changes after rotatory behavior test. Instead of Ad -GDNF, Ad -LacZ injected PD rats were used as a control. The following results are obtained: 1. The apomorphine -induced rotational behavior was significantly reduced by the treatment of PD rat by the injection of Ad -GDNF. The Ad -LacZ injected PD rat showed no change in rotatory behavior. 2. The density of TH -ir axon terminals in the striatum was significantly increased by the Ad -GDNF injection (75% of normal side), but there was no change in the density by the Ad -LacZ injection (37% of normal side) compared to 6 - OHDA lesioned striatum. This means the Ad -GDNF injection prevented the degenerative change of TH -ir axon terminals in the stritum of the PD rat. 3. The number of TH -ir cell body was significantly recovered by the Ad -GDNF (82% of normal side), but there was not recovered by the Ad -LacZ injection (60% of normal side) compared to 6 -OHDA lesion. This means the retrogradely transported Ad -GDNF induced the TH expression in the dopaminergic neurons of the substantia nigra. Gene therapy with Ad -GDNF prevented the degeneration of dopaminergic neurons and axon terminals in the 6 - OHDA -induced PD rat.

Morphological Changes in the Striatum after Dopaminergic Cell Transplantation to Parkinson's Disease Rat Model / 대한해부학회지

Parkinson's disease animal model was developed by the destruction of the striatonigral dopaminergic system. The morphological changes in the dopamine depleted striatum after the transplantation of the fetal mesencephalic dopaminergic neurons or tyrosine hydroxylase cDNA transfected human neural stem cells (C4-TH cells) were studied. Male Sprague-Dawley rats, weighting 250~300 gm, were used. To make unilateral lesion of nigrostriatal tract, 6-OHDA (6 microgram/microliter) was injected into the medial forebrain bundle. Two weeks after the lesion surgery, the effect of the 6-OHDA lesion was assessed by monitoring apomorphine (0.5 mg/kg, s.c)-induced turning behavior and confirmed by the lack of TH-immunoreactivity on tissue sections. Either cell suspension from ventral mesencephalic tissue obtained from embryonic day 14 fetus or C4-TH cells was grafted into the rostral striatum. After grafting, rats were tested with apomorphine every 2 weeks for 6 weeks. The grafted rats showing behavioral recovery were sacrificed and analysed by TH, neuropeptide Y (NPY), and parvalbumin (PV) immuno- histochemistry. TH-immunoreactive (ir) neurons were located around the graft and their processes extended into the striatum. The TH-ir axon terminals made a symmetrical synapse with the dendrites of the striatal neuron. Cell bodies either NPY- or PV-ir striatal neuron were observed around the graft and extended their processes into the graft. TH-ir C4-TH cells were also distributed along the needle track such as the transplanted fetal dopaminergic neurons, but had smaller soma and fewer processes than those. It is concluded that the grafted dopaminergic cells are survived in the dopamine depleted striatum and recovered the rotational behavior of Parkinson's disease animal model.