EurekaMag.com logo
+ Translate

Regulation of glycogen metabolism in primary cultures of rat hepatocytes. Restoration of acute effects of glucose in cells from diabetic rats involves protein synthesis


, : Regulation of glycogen metabolism in primary cultures of rat hepatocytes. Restoration of acute effects of glucose in cells from diabetic rats involves protein synthesis. Journal of Biological Chemistry 262(9): 4000-4006

Defective acute regulation of hepatic glycogen synthase by glucose and insulin, caused by severe insulin deficiency, can be corrected in adult rat hepatocytes in primary culture by inclusion of insulin, triiodothyronine, and cortisol in a chemically defined serum-free culture medium over a 3-day period (Miller, T. B., Jr., Garnache, A. K., Cruz, J., McPherson, R. K., and Wolleben, C. (1986) J. Biol. Chem. 261, 785-790). Using primary cultures of hepatocytes isolated from normal and diabetic rats in the same serum-free chemically defined medium, the present study addresses the effects of cycloheximide and actinomycin D on the chronic actions of insulin, triiodothyronine, and cortisol to facilitate the direct effects of glucose on the short-term activation of glycogen synthase. The short-term presence (1 h) of the protein synthesis blockers had no effect on acute activation of glycogen synthase by glucose in primary hepatocyte cultures from normal rats. Normal cells maintained in the presence of cycloheximide or actinomycin D for 2 and 3 days exhibited unimpaired responsiveness to glucose activation of synthase. The protein synthesis inhibitors were effective at blocking the restoration of glucose activation of synthase in diabetic cells in media which restored the activation in their absence. Restoration of glycogen synthase phosphatase activity by insulin, triiodothyronine, and cortisol in primary cultures of diabetic hepatocytes was also blocked by cycloheximide or actinomycin D. These data clearly demonstrate that restoration of acute glycogen synthase activation by glucose and restoration of glycogen synthase phosphatase activity in primary cultures of hepatocytes from adult diabetic rats are dependent upon the synthesis of new protein.

(PDF 0-2 workdays service)

Accession: 006288167

PMID: 3104335

Submit PDF Full Text: Here


Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:
Close
Close

Related references

Miller, T.B.; Garnache, A.K.; Cruz, J.; McPherson, R.K.; Wolleben, C., 1986: Regulation of glycogen metabolism in primary cultures of rat hepatocytes. Restoration of acute effects of insulin and glucose in cells from diabetic rats. Defects in the deposition of glycogen and the regulation of glycogen synthesis in the livers of severely insulin-deficient rats can be reversed, in vivo, within hours of insulin administration. Using primary cultures of hepatocytes isolated from n...

Miller, T.B., 1979: Glucose activation of liver glycogen synthase. Insulin-mediated restoration of glucose effect in diabetic rats is blocked by protein synthesis inhibitor. The loss of glucose regulation of glycogen synthase in perfused livers from diabetic rats was associated with a substantial reduction in synthase phosphatase activity. Treatment of diabetic rats with insulin alone resulted in total restoration of...

Miller T.B.Jr, 1979: Glucose activation of liver glycogen synthase insulin mediated restoration of glucose effect in diabetic rats in blocked by protein synthesis inhibitor. The loss of glucose regulation of glycogen synthase in perfused livers from diabetic rats was associated with a substantial reduction in synthase phosphatase activity. Treatment of diabetic rats with insulin alone resulted in total restoration of...

Bellemann, P.; Fry, J.R.; Bridges, J.W.; Schlote, W.; Mecke, D., 1977: Effect of insulin on glycogen and protein synthesis in monolayer cultures of hepatocytes from normal and alloxan diabetic rats. The effects of insulin on net glycogen synthesis and amino acid incorporation into protein were studied in cultured hepatocytes from adult normal and alloxan diabetic rats. Insulin stimulated glycogen synthesis in monolayer cells throughout a four...

Amatruda J.M.; Chang C.L., 1983: Regulation of lipid synthesis in primary cultures of hepatocytes from nonketotic streptozotocin diabetic rats. Primary cultures of rat hepatocytes were utilized to study insulin resistance in the liver of nonketotic streptozotocin diabetic animals. Normal control and 72-h fasted animals were also studied for comparison. Basal lipogenesis in primary culture...

Amatruda, J.M.; Chang, C.L., 1983: The regulation of lipid synthesis in primary cultures of hepatocytes from nonketotic streptozotocin diabetic rats. Primary cultures of rat hepatocytes were used to study insulin resistance in the liver of nonketotic streptozotocin diabetic animals. Basal lipogenesis in primary cultures of hepatocytes from rats deprived of food for 72 h is 47% of that in hepato...

Morales, M.; López-Delgado, M.I.; Alcántara, A.; Luque, M.A.; Clemente, F.; Márquez, L.; Puente, J.; Viñambres, C.; Malaisse, W.J.; Villanueva-Peñacarrillo, M.L.; Valverde, I., 1997: Preserved GLP-I effects on glycogen synthase a activity and glucose metabolism in isolated hepatocytes and skeletal muscle from diabetic rats. To search if biological effects of GLP-I on glucose metabolism in extrapancreatic tissue are present in diabetic states, we have studied the action of GLP-I and insulin on glycogen-enzyme activity, glycogen synthesis, and glucose metabolism in iso...

Ciaraldi, T.P.; Carter, L.; Nikoulina, S.; Mudaliar, S.; Mcclain, D.A.; Henry, R.R., 1999: Glucosamine regulation of glucose metabolism in cultured human skeletal muscle cells: Divergent effects on glucose transport/phosphorylation and glycogen synthase in non-diabetic and type 2 diabetic subjects. Chronic exposure (48 h) to glucosamine resulted in a dose-dependent reduction of basal and insulin-stimulated glucose uptake activities in human skeletal muscle cell cultures from nondiabetic and type 2 diabetic subjects. Insulin responsiveness of...

Ciaraldi, T.P.; Carter, L.; Nikoulina, S.; Mudaliar, S.; McClain, D.A.; Henry, R.R., 1999: Glucosamine regulation of glucose metabolism in cultured human skeletal muscle cells: divergent effects on glucose transport/phosphorylation and glycogen synthase in non-diabetic and type 2 diabetic subjects. Chronic exposure (48 h) to glucosamine resulted in a dose-dependent reduction of basal and insulin-stimulated glucose uptake activities in human skeletal muscle cell cultures from nondiabetic and type 2 diabetic subjects. Insulin responsiveness of...

Morales, M.; Lopez Delgado, M.I.; Alcantara, A.; Luque, M.A.; Clemente, F.; Marquez, L.; Puente, J.; Vinambres, C.; Malaisse, W.J.; Villanueva Penacarrillo, M.L.; Valverde, I., 1997: Preserved GLP-I effects on glycogen synthase alpha activity and glucose metabolism in isolated hepatocytes and skeletal muscle from diabetic rats. To search if biological effects of GLP-1 on glucose metabolism in extrapancreatic tissue are present in diabetic states, we have studied the action of GLP-I and insulin on glycogen-enzyme activity, glycogen synthesis, and glucose metabolism in iso...