title: Insulin resistance in the liver: deficiency or excess of insulin?
abstract: In insulin-resistant states (obesity, pre-diabetes, and type 2 diabetes), hepatic production of glucose and lipid synthesis are heightened in concert, implying that insulin deficiency and insulin excess coexists in this setting. The fact that insulin may be inadequate or excessive at any one point in differing organs and tissues has many biologic ramifications. In this context the concept of metabolic compartmentalization in the liver is offered herein as one perspective of this paradox. In particular, we focus on the hypothesis that insulin resistance accentuates differences in periportal and perivenous hepatocytes, namely periportal glucose production and perivenous lipid synthesis. Subsequently, excessive production of glucose and accumulation of lipids could be expected in the livers of patients with obesity and insulin resistance. Overall, in this review, we provide our integrative perspective regarding how excessive production of glucose in periportal hepatocytes and accumulation of lipids in perivenous hepatocytes interact in insulin resistant states.
authors.affiliation: a Department of Pharmacology and Therapeutics ; State University of Maringá ; Maringá , Paraná , PR Brazil.
authors.forename: Roberto B
authors.initials: RB
authors.lastname: Bazotte
authors.forename: Lorena G
authors.initials: LG
authors.lastname: Silva
authors.forename: Fabiana Pm
authors.initials: FP
authors.lastname: Schiavon
mesh_terms: D000818:Animals; D005947:Glucose / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000172:deficiency / Q000378:metabolism*; D007333:Insulin Resistance; D050356:Lipid Metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism*
chemical_list: D007328:Insulin; D005947:Glucose
keywords: hyperinsulinism; insulin resistance; liver glucose production; liver lipogenesis; nonparenchymal liver cells; obesity; periportal hepatocytes; perivenous hepatocytes; type 2 diabetes