| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Regular Articles |
From the Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
Studies with I125-labeled low-density lipoproteins
(LDLs) have shown the presence of high-affinity LDL receptors on
insulin-producing ß cells but not on neighboring 
cells. By using
gold-labeled lipoproteins, we demonstrate receptor-mediated
endocytosis of LDLs and very low-density lipoproteins in rat and human
ß cells. Specific for human ß cells is the fusion of LDL-containing
endocytotic vesicles with lipid-storing vesicles (LSVs;
diameter, 0.6–3.6 µm), which are absent in rodent
ß cells. LSVs also occur in human pancreatic and duct
cells, but these sequester little gold-labeled LDL. In humans
<25 years old, LSVs occupy 1% of the cytoplasmic surface area
in ß, , and duct cells. In humans >50 years
old, LSV surface area in ß cells (11 ± 2% of
cytoplasmic surface area) is fourfold higher than in and duct cells
and 10-fold higher than in ß cells at younger ages
(P < 0.001); the mean LSV diameter in these ß
cells (1.8 ± 0.04 µm) is larger than at younger ages (1.1
± 0.2 µm; P < 0.005). Oil red O staining on
pancreatic sections confirms that neutral lipids accumulate in ß
cells of older donors. We conclude that human ß cells can incorporate
LDL and very low-density lipoprotein material in LSVs. The marked
increase in the LSV area of aging human ß cells raises the question
whether it is caused by prolonged exposure to high lipoprotein levels
such as occurs in Western populations and whether it is causally
related to the higher risk for type 2 diabetes with
aging.
This article has been cited by other articles:
 |
|
 |
|
  L. Marselli, J. Thorne, Y.-B. Ahn, A. Omer, D. C. Sgroi, T. Libermann, H. H. Otu, A. Sharma, S. Bonner-Weir, and G. C. Weir Gene Expression of Purified {beta}-Cell Tissue Obtained from Human Pancreas with Laser Capture Microdissection J. Clin. Endocrinol. Metab., March 1, 2008; 93(3): 1046 - 1053. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Ovalle and D. S.H. Bell Effect of Rosiglitazone Versus Insulin on the Pancreatic {beta}-Cell Function of Subjects With Type 2 Diabetes Diabetes Care, November 1, 2004; 27(11): 2585 - 2589. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M.-E. Roehrich, V. Mooser, V. Lenain, J. Herz, J. Nimpf, S. Azhar, M. Bideau, A. Capponi, P. Nicod, J.-A. Haefliger, et al. Insulin-secreting beta -Cell Dysfunction Induced by Human Lipoproteins J. Biol. Chem., May 9, 2003; 278(20): 18368 - 18375. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Cnop, J. C. Hannaert, A. Y. Grupping, and D. G. Pipeleers Low Density Lipoprotein Can Cause Death of Islet {beta}-Cells by Its Cellular Uptake and Oxidative Modification Endocrinology, September 1, 2002; 143(9): 3449 - 3453. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Andreolas, G. da Silva Xavier, F. Diraison, C. Zhao, A. Varadi, F. Lopez-Casillas, P. Ferre, F. Foufelle, and G. A. Rutter Stimulation of Acetyl-CoA Carboxylase Gene Expression by Glucose Requires Insulin Release and Sterol Regulatory Element Binding Protein 1c in Pancreatic MIN6 {beta}-Cells Diabetes, August 1, 2002; 51(8): 2536 - 2545. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. J. G. Hanley, G. McKeown-Eyssen, S. B. Harris, R. A. Hegele, T. M. S. Wolever, J. Kwan, and B. Zinman Cross-Sectional and Prospective Associations between Abdominal Adiposity and Proinsulin Concentration J. Clin. Endocrinol. Metab., January 1, 2002; 87(1): 77 - 83. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. E. Kahn The Importance of {beta}-Cell Failure in the Development and Progression of Type 2 Diabetes J. Clin. Endocrinol. Metab., September 1, 2001; 86(9): 4047 - 4058. [Full Text] [PDF]
|
|
|
|
 |
|
 R. H. UNGER and L. ORCI Diseases of liporegulation: new perspective on obesity and related disorders FASEB J, February 1, 2001; 15(2): 312 - 321. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
