In Vivo Adenoviral Delivery of Recombinant Human Protein Kinase C-ζ Stimulates Glucose Transport Activity in Rat Skeletal Muscle

• Published in: The Journal of biological chemistry 1999-08, Vol.274 (32), p.22139
• Main Authors: Garret J. Etgen, Kathleen M. Valasek, Carol L. Broderick, Anne R. Miller
• Format: Article
• Language: English
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1074/jbc.274.32.22139

An in vivo adenoviral gene delivery system was utilized to assess the effect of overexpressing protein kinase C (PKC)-ζ on rat skeletal muscle glucose transport activity. Female lean Zucker rats were injected with adenoviral/human PKC-ζ (hPKC-ζ) and adenoviral/LacZ in opposing tibialis anterior muscles. One week subsequent to adenoviral/gene delivery rats were subjected to hind limb perfusion. The hPKC-ζ protein was expressed at the same level (fast-twitch white) or at ∼80% of the level (fast-twitch red) of endogenous PKC-ζ, thus approximately doubling the amount of PKC-ζ in tibialis anterior. Basal glucose transport activity was elevated ∼3.4- and 2-fold, respectively, in fast-twitch white and red hPKC-ζ muscle relative to control. Submaximal insulin-stimulated glucose transport activity, corrected for basal transport, was ∼90 and 40% over control values, respectively, in fast-twitch white and red hPKC-ζ muscle. The enhancement of glucose transport activity in muscle expressing hPKC-ζ occurred in the absence of any change in GLUT1 or GLUT4 protein levels, suggesting a redistribution of existing transporters to the cell surface. These results demonstrate that an adenoviral vector can be used to deliver expressible hPKC-ζ to adult rat skeletal muscle in vivo and also affirm a role for PKC-ζ in the regulation of glucose transport activity.