Insulin secretion is highly sensitive to desorption of plasma membrane cholesterol.

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Cholesterol-rich clusters of SNARE (soluble NSF attachment protein receptor) proteins have been implicated as being important for exocytosis. Here we demonstrate the significance of cholesterol for normal biphasic insulin secretion in mouse beta cells by removal of cholesterol from the plasma membrane using methyl-beta-cyclodextrin (MBCD). Maximal inhibition of insulin secretion in static incubations was achieved using 0.1 mM MBCD. In in situ pancreatic perfusion measurements, both first and second phase insulin secretions were reduced by approximately 50% (P<0.05). This was accompanied by a reduced number of docked large dense core vesicles (LDCVs) ( approximately 40%; P<0.01) and a reduced exocytotic response (>50%; P<0.01). Further, subcellular fractionations demonstrated movement of the synaptosomal protein of 25 kDa (SNAP-25) from the plasma membrane to the cytosol after MBCD treatment. The inhibitory actions of MBCD were counteracted by subsequent addition of cholesterol. We hypothesize that desorption of cholesterol leads to the disturbance of a basic exocytotic mechanism partly due to migration of SNAP-25, and we conclude that insulin secretion is highly sensitive to changes in plasma membrane cholesterol.-Vikman, J., Jimenez-Feltström, J., Nyman, P., Thelin, J., Eliasson, L. Insulin secretion is highly sensitive to desorption of plasma membrane cholesterol.

Detaljer

Författare
  • Jenny Vikman
  • Javier Jimenez
  • Per Nyman
  • Johan Thelin
  • Lena Eliasson
Enheter & grupper
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Cell- och molekylärbiologi
Originalspråkengelska
Sidor (från-till)58-67
TidskriftThe FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Volym23
Utgåva nummer1
StatusPublished - 2009
PublikationskategoriForskning
Peer review utfördJa