ABSTRACT
To examine the ability of intrastriatal gene transfer of vascular endothelial growth factor 165 mediated by adenoviral vector to rescue dopaminergic neurons in a rat model of Parkinson's disease (PD), we constructed recombinant replication-deficent adenoviral vectors carrying the gene of VEGF165 (Ad-VEGF), and injected Ad-VEGF (or Ad-LacZ and PBS as controls) into the striatum of rats 7 days after the lesion by 6-hydroxydopamine. The rat rotational behavior analysis and tyrosine hydroxylase (TH) immunohistochemistry were performed to assess the change of dopaminergic neurons. Our results showed that the rats receiving Ad-VEGF injection displayed a significant improvement in apomorphine-induced rotational behavior and a significant preservation of TH-positive neurons and fibers compared with control animals. It is concluded that intrastriatal gene transfer by Ad-VEGF may rescue the dopaminergic neurons from degeneration in a rat model of PD.
ABSTRACT
Objective To investigate the role of overexpression of Smad7,the inhibitory factor of TGF-?/Smads signaling,in epithelial-mesenchymal transition (EMT) of peritoneal mesothelial cells.Methods Peritoneal fibrosis rat model was built by daily intraperitoneal injection with 4.25% Dineal (100 ml/kg) and lipopolysaccharide(LPS) (0.6 mg/kg) at day 8,10,12,22,24,26. Smad7 or control empty vectors was transferred at day 0,14 and was induced by doxycline in the daily drinking water (200 mg/L).Rats were sacrificed on day 28 and the expression of TGF-beta/ Smads,?-SMA and E-cadherin was examined.Results Compared with normal rats,empty vector rats showed higher expression of phosphorylated Smad2/3.?-SMA expression was elevated but E-cadherin was reduced.Under electron microscope,the mesothelial cells removed to submesothelial zone and showed large bundles of actin microfilaments and dense bodies within the cytoplasm. Basement membrane was broken.After induction of Smad7 in peritoneal fibrosis rats,the morphology of mesothelial ceils normalized partly,phosphorylated Smad2/3 was reduced.Moreover,expression of E-cadherin was increased,expression of?-SMA was dramatically reduced.Conclusion Inhibition of TGF-?/Smad signaling by Smad7 overexpression may inhibit the epithelial-mesenchymal transition of mesothelial cell,which may provide a new therapeutic method for peritoneal fibrosis by overexpression of Smad7.