Reduction of islet amylin expression and basal secretion by adenovirus-mediated delivery of amylin antisense cDNA.
Reduction of amylin content and secretion in rat islets was attempted by transduction with an adenovirus bearing a 0.2-kb fragment of rat amylin cDNA inserted in the antisense orientation (AdCMV-alpha amylin). Exposure of islets to AdCMV-alpha amylin at a multiplicity of infection (moi) of 200 (1.2 x 10(7) pfu/ml) reduced amylin mRNA levels by 37 +/- 5% (p < 0.005), whereas infection with an adenovirus expressing the reporter gene of beta-galactosidase (AdCMV-lacz) did not modify amylin expression. Transduction with the antisense construct was specifically associated with the decrease (30 +/- 6%; p < 0.001) in the amylin content. Insulin content was unaltered in AdCMV-alpha amylin islets compared to AdCMV-lacz-transduced or untransduced cells. Basal amylin secretion (2.8 mM glucose) was 36 +/- 3% (p < 0.005) lower in AdCMV-alpha amylin islets than in untransduced or AdCMV-lacz-transduced islets. In contrast, no difference in amylin secretion in response to high glucose concentrations (16.7 mM) was detected in AdCMV-alpha amylin-transduced islets. Thus, a reduction of amylin content and basal secretion in islet cells can be achieved by the adenovirus-mediated expression of antisense RNA.
Departament d'Endocrinologia i Diabetis, Hospital Clínic, Universitat de Barcelona, Spain.
A
A
Novials
J C
JC
Jiménez-Chillarón
C
C
Franco
R
R
Casamitjana
R
R
Gomis
A M
AM
Gómez-Foix
D000256:Adenoviridae / Q000235:genetics*; D000682:Amyloid / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D017931:DNA Primers / Q000737:chemistry; D016373:DNA, Antisense / Q000235:genetics*; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D007328:Insulin / Q000235:genetics; D058228:Islet Amyloid Polypeptide; D007515:Islets of Langerhans / Q000166:cytology / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D001616:beta-Galactosidase / Q000378:metabolism
D000682:Amyloid; D017931:DNA Primers; D016373:DNA, Antisense; D007328:Insulin; D058228:Islet Amyloid Polypeptide; D001616:beta-Galactosidase