β-cell dysfunction under hyperglycemic stress

A molecular model

Florin Despa, R. Stephen Berry

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Background: Pancreatic β cells respond to chronic hyperglycemia by increasing the synthesis of proinsulin (the precursor molecule of insulin). Prolonged stimulations lead to accumulation of misfolded proinsulin in the secretory track, delayed insulin secretion, and release of unprocessed proinsulin in the blood. The molecular mechanisms connecting the state of endoplasmic reticulum overloading with the efficiency of proinsulin to insulin conversion remain largely unknown. Method: Computer simulations can help us to understand mechanistic features of the β-cell secretory defect and to design experiments that may reveal the molecular basis of this dysfunction. We used molecular crowding concepts and statistical thermodynamics to dissect possible biophysical mechanisms underlying the alteration of the secretory track of β cells and to elucidate the chemistry aspects of the secretory dysfunction. We then used numerical algorithms to relate the degree of biophysical alteration of these secretory compartments with the change of proinsulin to insulin conversion rate. Results: Our computer simulations suggest that overloading the endoplasmic reticulum initiates downstream molecular crowding effects that affect protein translational mechanisms, including proinsulin misfolding, delayed packing of proinsulin in secretory vesicles, and low kinetic coefficient of proinsulin to insulin conversion. Conclusions: Together with previous experimental data, the present study can help us to better understand chemistry aspects related to the secondary translational mechanisms in β cells and how hyperglycemic stress can alter secretory function. This can give a further impetus to the development of novel software to be used in a clinical setup for prediction and assessment of diabetic states in susceptible patients.

Original languageEnglish (US)
Pages (from-to)1447-1456
Number of pages10
JournalJournal of diabetes science and technology
Volume4
Issue number6
StatePublished - Nov 2010

Fingerprint

Proinsulin
Molecular Models
Insulin
Statistical mechanics
Endoplasmic Reticulum
Computer Simulation
Computer simulation
Blood
Secretory Vesicles
Proteins
Defects
Thermodynamics
Molecules
Kinetics
Hyperglycemia
Software
Experiments

Keywords

  • Endoplasmic reticulum stress
  • Hyperglycemia
  • Insulin
  • Molecular crowding
  • Proinsulin
  • Type 2 diabetes mellitus

ASJC Scopus subject areas

  • Endocrinology, Diabetes and Metabolism
  • Internal Medicine
  • Bioengineering
  • Biomedical Engineering

Cite this

β-cell dysfunction under hyperglycemic stress : A molecular model. / Despa, Florin; Stephen Berry, R.

In: Journal of diabetes science and technology, Vol. 4, No. 6, 11.2010, p. 1447-1456.

Research output: Contribution to journalArticle

Despa, Florin ; Stephen Berry, R. / β-cell dysfunction under hyperglycemic stress : A molecular model. In: Journal of diabetes science and technology. 2010 ; Vol. 4, No. 6. pp. 1447-1456.
@article{0704a22134ae4f2f89b39cdc53a69869,
title = "β-cell dysfunction under hyperglycemic stress: A molecular model",
abstract = "Background: Pancreatic β cells respond to chronic hyperglycemia by increasing the synthesis of proinsulin (the precursor molecule of insulin). Prolonged stimulations lead to accumulation of misfolded proinsulin in the secretory track, delayed insulin secretion, and release of unprocessed proinsulin in the blood. The molecular mechanisms connecting the state of endoplasmic reticulum overloading with the efficiency of proinsulin to insulin conversion remain largely unknown. Method: Computer simulations can help us to understand mechanistic features of the β-cell secretory defect and to design experiments that may reveal the molecular basis of this dysfunction. We used molecular crowding concepts and statistical thermodynamics to dissect possible biophysical mechanisms underlying the alteration of the secretory track of β cells and to elucidate the chemistry aspects of the secretory dysfunction. We then used numerical algorithms to relate the degree of biophysical alteration of these secretory compartments with the change of proinsulin to insulin conversion rate. Results: Our computer simulations suggest that overloading the endoplasmic reticulum initiates downstream molecular crowding effects that affect protein translational mechanisms, including proinsulin misfolding, delayed packing of proinsulin in secretory vesicles, and low kinetic coefficient of proinsulin to insulin conversion. Conclusions: Together with previous experimental data, the present study can help us to better understand chemistry aspects related to the secondary translational mechanisms in β cells and how hyperglycemic stress can alter secretory function. This can give a further impetus to the development of novel software to be used in a clinical setup for prediction and assessment of diabetic states in susceptible patients.",
keywords = "Endoplasmic reticulum stress, Hyperglycemia, Insulin, Molecular crowding, Proinsulin, Type 2 diabetes mellitus",
author = "Florin Despa and {Stephen Berry}, R.",
year = "2010",
month = "11",
language = "English (US)",
volume = "4",
pages = "1447--1456",
journal = "Journal of diabetes science and technology",
issn = "1932-2968",
publisher = "Diabetes Technology Society",
number = "6",

}

TY - JOUR

T1 - β-cell dysfunction under hyperglycemic stress

T2 - A molecular model

AU - Despa, Florin

AU - Stephen Berry, R.

PY - 2010/11

Y1 - 2010/11

N2 - Background: Pancreatic β cells respond to chronic hyperglycemia by increasing the synthesis of proinsulin (the precursor molecule of insulin). Prolonged stimulations lead to accumulation of misfolded proinsulin in the secretory track, delayed insulin secretion, and release of unprocessed proinsulin in the blood. The molecular mechanisms connecting the state of endoplasmic reticulum overloading with the efficiency of proinsulin to insulin conversion remain largely unknown. Method: Computer simulations can help us to understand mechanistic features of the β-cell secretory defect and to design experiments that may reveal the molecular basis of this dysfunction. We used molecular crowding concepts and statistical thermodynamics to dissect possible biophysical mechanisms underlying the alteration of the secretory track of β cells and to elucidate the chemistry aspects of the secretory dysfunction. We then used numerical algorithms to relate the degree of biophysical alteration of these secretory compartments with the change of proinsulin to insulin conversion rate. Results: Our computer simulations suggest that overloading the endoplasmic reticulum initiates downstream molecular crowding effects that affect protein translational mechanisms, including proinsulin misfolding, delayed packing of proinsulin in secretory vesicles, and low kinetic coefficient of proinsulin to insulin conversion. Conclusions: Together with previous experimental data, the present study can help us to better understand chemistry aspects related to the secondary translational mechanisms in β cells and how hyperglycemic stress can alter secretory function. This can give a further impetus to the development of novel software to be used in a clinical setup for prediction and assessment of diabetic states in susceptible patients.

AB - Background: Pancreatic β cells respond to chronic hyperglycemia by increasing the synthesis of proinsulin (the precursor molecule of insulin). Prolonged stimulations lead to accumulation of misfolded proinsulin in the secretory track, delayed insulin secretion, and release of unprocessed proinsulin in the blood. The molecular mechanisms connecting the state of endoplasmic reticulum overloading with the efficiency of proinsulin to insulin conversion remain largely unknown. Method: Computer simulations can help us to understand mechanistic features of the β-cell secretory defect and to design experiments that may reveal the molecular basis of this dysfunction. We used molecular crowding concepts and statistical thermodynamics to dissect possible biophysical mechanisms underlying the alteration of the secretory track of β cells and to elucidate the chemistry aspects of the secretory dysfunction. We then used numerical algorithms to relate the degree of biophysical alteration of these secretory compartments with the change of proinsulin to insulin conversion rate. Results: Our computer simulations suggest that overloading the endoplasmic reticulum initiates downstream molecular crowding effects that affect protein translational mechanisms, including proinsulin misfolding, delayed packing of proinsulin in secretory vesicles, and low kinetic coefficient of proinsulin to insulin conversion. Conclusions: Together with previous experimental data, the present study can help us to better understand chemistry aspects related to the secondary translational mechanisms in β cells and how hyperglycemic stress can alter secretory function. This can give a further impetus to the development of novel software to be used in a clinical setup for prediction and assessment of diabetic states in susceptible patients.

KW - Endoplasmic reticulum stress

KW - Hyperglycemia

KW - Insulin

KW - Molecular crowding

KW - Proinsulin

KW - Type 2 diabetes mellitus

UR - http://www.scopus.com/inward/record.url?scp=79953010862&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79953010862&partnerID=8YFLogxK

M3 - Article

VL - 4

SP - 1447

EP - 1456

JO - Journal of diabetes science and technology

JF - Journal of diabetes science and technology

SN - 1932-2968

IS - 6

ER -