ABSTRACT
Objective To observe the curative effect of transplantation of mesenchymal stem cells (MSCs) transfected with recombinant lentiviral vectors carrying brain-derived neurotrophic factor (BDNF) gene on intracerebral hemorrhage in rats.Methods MSCs were isolated from the rat bone marrow,cultured and transfected by recombinant lentiviral vectors carrying BDNF gene.Intracerebral hemorrhagic models were constructed and randomly divided into 4 groups:phosphate buffered saline transplanted (PBS) group,MSCs group,mesenchymal stem cells transfected with empty lentiviral vectors transplanted (MSCs-EGFP) group and mesenchymal stem cells transfected with recombinant lentiviral vectors carrying brain-derived neurotrophic factor gene transplanted (MSCs-EGFP-BDNF) group.PBS and MSCs were transplanted according to the groups 72 hours after the establishment of models.The improvements of the neurological function were recorded of each group 7 d,14 d,and 21 d after the transplantation.Double labeling immunofluorescent staining were used to detect the migration and the differentiation of transplanted MSCs.Results MSCs-EGFP-BDNF group had significant higher levels of BDNF gene and protein expression than MSCs group and MSCs-EGFP group.All MSCs transplanted groups (MSCs groups:7 d:1.6 ±0.2,14 d:1.2 ±0.3,21 d:0.8 ±0.2; MSCs-EGFP groups:7 d:1.6 ±0.3,14 d:1.1 ±0.2,21 d:0.8 ±0.3; MSCs-EGFP-BDNFgroup:7 d:1.2 ±0.3,14 d:0.6 ±0.1,21 d:0.2±0.2) had more improvements in the neural function (F=6.667,18.417,20.882,all P ＜0.05) than PBS group(7 d:2.0 ±0.4,14 d:1.7 ±0.2,21 d:1.3 ±0.2),and MSCs-EGFP-BDNF group had the most significant improvement.With double labeling immunofluorescent staining,the MSCs-EGFP-BDNF group had significantly higher positive rates of glial fibrilary acidicprotein,neuron specific nuclear protein,2',3 '-cyclic nucleotide 3'-phosphodiesterase than MSCs group and MSCs-EGFP group,while there was no significant differences between the latter two.Conclusions The expression levels of gene and protein are higher for the MSCs modified with recombinant lentiviral vectors carrying BDNF gene.The modified MSCs can migrate to the perihematomal brain issue of intracerebral hemorrhage,express the characteristic molecules of neurons and improve the neural function after intracerebral hemorrhage.
ABSTRACT
Objective To investigate expression of β-site APP-cleaving enzymel(BACE1) and Aβ in brain of diabetes mellitus of Wistar rats,to study pathophysiological mechanism of Alzheimer disease from diabetic metabolic disorder. Methods Animal model of diabetes mellitus was established by streptozocin with intraperitoneal injection. Wistar rats were randomly divided into normal group (N), sham-operation group (S), 4 weeks diabetes mellitus model group (M4), 6 weeks diabetes mellitus model group (M6) and 8 weeks diabetes mellitus model group (M8). Behaviour was tested with Morris water maze and shuttle box test. Expression of Aβ was measured by enzyme linked immunosorbent assay and BACE1 by immunohistochemistry, enzyme linked immunosorbent assay, Western blotting and RT-PCR. The absorbance value was measured by imaging analysis. Results The electric times and latancy of memory and study were more increased in model group than that in N and S group but the times of escape more decreased(P<0.01). The expression of Aβ_(1-40) increased from (64.13±6.76)pg/mg in normal group to (86.43±7.03)pg/mg in model group by ELISA(P<0.001) and Aβ_(1-42) from (67.43±5.12 )pg/mg in normal group to (89.45±5.28) pg/mg (P<0.001) in model group. The expression of BACE1 increased from (116.46±8.10)pg/mg in normal group to (158.73±6.24)pg/mg in model group by ELISA and from 0.61±0.11 in normal group to 1.52±0.16 by Western blotting absorbance valule and from 1.62±0.26 in normal group to 3.61±0.32 by RT-PCR absorbance valule and from 0.81±0.21 in normal group to 2.01±0.36 by immunohistochemistry absorbance valule (P<0.001). The expression of BACE1 and Aβ in MT group was higher than that of in N and S group (P<0.01). The level of BACE1 and Aβ had positive correlation with cognitive impairment.Conclusion The expression of BACE1 and Aβ is increased in diabetes mellitus rats. Diabetes mellitus contributes to Alzheimer diseases that.
ABSTRACT
Chronic cerebral hypoperfusion (CCH) increases the risk of Alzheimer disease (AD) through several biologically plausible pathways, but the relationship between CCH and the development of AD remains uncertain. To investigate expression of APP, BACE1 and A beta in the hippocampus of BCCAO rats and study pathophysiological mechanism of AD from CCH. CCH rat model was established by chronic bilateral common carotid artery occlusion (BCCAO). Behavior was evaluated after BCCAO with Morris water maze and open-field task. Expression of A beta was measured by enzyme linked immunosorbent assay (ELISA). beta-Amyloid precursor protein cleavage enzyme 1 (BACE1) and beta-amyloid precursor protein (APP) were tested by ELISA, Western blotting and RT-PCR. Cognitive impairment occurred with CCH by Morris water maze test and open-field task. The BACE1 and A beta level in BCCAO rats was more increased than sham-operation control rats (P < 0.01) but APP had no difference(P > 0.05). The expression of BACE1 and A beta has no inter-group difference in BCCAO rats (P > 0.05). The level of BACE1 and A beta had positive correlation with cognitive impairment (P < 0.01) while no correlation was observed between APP and cognitive impairment. Chronic cerebral ischemia contributes to cognitive impairment and vascular pathogenesis of Alzheimer's disease that chronic cerebral hypoperfusion increases BACE1 and A beta level in brain.
