title: Rosuvastatin Treatment Affects Both Basal and Glucose-Induced Insulin Secretion in INS-1 832/13 Cells.
abstract: Rosuvastatin is a member of the statin family. Like the other statins it is prescribed to lower cholesterol levels and thereby reduce the risk of cardiovascular events. Rosuvastatin lowers the cholesterol levels by inhibiting the key enzyme 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA reductase) in the cholesterol producing mevalonate pathway. It has been recognized that apart from their beneficial lipid lowering effects, statins also exhibit diabetogenic properties. The molecular mechanisms behind these remain unresolved. To investigate the effects of rosuvastatin on insulin secretion, we treated INS-1 832/13 cells with varying doses (20 nM to 20 μM) of rosuvastatin for 48 h. At concentrations of 2 μM and above basal insulin secretion was significantly increased. Using diazoxide we could determine that rosuvastatin did not increase basal insulin secretion by corrupting the KATP channels. Glucose-induced insulin secretion on the other hand seemed to be affected differently at different rosuvastatin concentrations. Rosuvastatin treatment (20 μM) for 24-48 h inhibited voltage-gated Ca(2+) channels, which lead to reduced depolarization-induced exocytosis of insulin-containing granules. At lower concentrations of rosuvastatin (≤ 2 μM) the stimulus-secretion coupling pathway was intact downstream of the KATP channels as assessed by the patch clamp technique. However, a reduction in glucose-induced insulin secretion could be observed with rosuvastatin concentrations as low as 200 nM. The inhibitory effects of rosuvastatin on glucose-induced insulin secretion could be reversed with mevalonate, but not squalene, indicating that rosuvastatin affects insulin secretion through its effects on the mevalonate pathway, but not through the reduction of cholesterol biosynthesis. Taken together, these data suggest that rosuvastatin has the potential to increase basal insulin secretion and reduce glucose-induced insulin secretion. The latter is possibly an unavoidable side effect of rosuvastatin treatment as it occurs through the same mechanisms as the lipid-lowering effects of the drug.
authors.affiliation: Unit of Islet Cell Exocytosis, Lund University Diabetes Centre, Dept. Clinical Sciences in Malmö, Lund University, Clinical Research Centre, SUS Malmö, Malmö, Sweden.
authors.forename: Vishal A
authors.initials: VA
authors.lastname: Salunkhe
authors.affiliation: Unit of Islet Cell Exocytosis, Lund University Diabetes Centre, Dept. Clinical Sciences in Malmö, Lund University, Clinical Research Centre, SUS Malmö, Malmö, Sweden.
authors.forename: Olof
authors.initials: O
authors.lastname: Elvstam
authors.affiliation: Unit of Islet Cell Exocytosis, Lund University Diabetes Centre, Dept. Clinical Sciences in Malmö, Lund University, Clinical Research Centre, SUS Malmö, Malmö, Sweden.
authors.forename: Lena
authors.initials: L
authors.lastname: Eliasson
authors.affiliation: Unit of Islet Cell Exocytosis, Lund University Diabetes Centre, Dept. Clinical Sciences in Malmö, Lund University, Clinical Research Centre, SUS Malmö, Malmö, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Wendt
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism; D002460:Cell Line; D003981:Diazoxide / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000494:pharmacology*; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects* / Q000378:metabolism; D015640:Ion Channel Gating / Q000187:drug effects; D054086:KATP Channels / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D008798:Mevalonic Acid / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D051381:Rats; D000068718:Rosuvastatin Calcium / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D015220:Calcium Channels; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007328:Insulin; D054086:KATP Channels; D014665:Vasodilator Agents; D000068718:Rosuvastatin Calcium; D005947:Glucose; D003981:Diazoxide; D008798:Mevalonic Acid; D002118:Calcium