New hepatic targets for glycaemic control in diabetes.
Type-2 diabetes is associated with impaired glucose clearance by the liver in the postprandial state, and with elevated glucose production in the post-absorptive state. New targets within the liver are currently being investigated for development of antihyperglycaemic drugs for type-2 diabetes. They include glucokinase, which catalyses the first step in glucose metabolism, the glucagon receptor, and enzymes of gluconeogenesis and/or glycogenolysis such as glucose 6-phosphatase, fructose 1,6-bisphosphatase and glycogen phosphorylase. Preclinical studies with candidate drugs on animal models or cell-based assays suggest that these targets have the potential for pharmacological glycaemic control. Data from clinical studies is awaited. Further work is required for better understanding of the implications of targeting these sites in terms of possible side-effects or tachyphylaxis. The advantage of combined targeting of two or more sites within the liver for minimizing side-effects and tachyphylaxis caused by single-site targeting is discussed.
Institute of Cellular Medicine, School of Clinical Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK. Loranne.Agius@ncl.ac.uk
Loranne
L
Agius
D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D006597:Fructose-Bisphosphatase / Q000037:antagonists & inhibitors; D005934:Glucagon / Q000037:antagonists & inhibitors; D005941:Glucokinase / Q000037:antagonists & inhibitors; D005943:Gluconeogenesis / Q000187:drug effects; D005952:Glucose-6-Phosphatase / Q000037:antagonists & inhibitors; D024981:Glycogen Phosphorylase / Q000037:antagonists & inhibitors; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D008099:Liver / Q000187:drug effects* / Q000378:metabolism
D001786:Blood Glucose; D004791:Enzyme Inhibitors; D007004:Hypoglycemic Agents; D005934:Glucagon; D024981:Glycogen Phosphorylase; D005941:Glucokinase; D006597:Fructose-Bisphosphatase; D005952:Glucose-6-Phosphatase