Expression pattern of 12-lipoxygenase in human islets with type 1 diabetes and type 2 diabetes.

Abstract

CONTEXT:

Inflammation in the pancreas can cause β-cell stress, leading to diabetes development. Access to human pancreas tissues via the Network for Pancreatic Organ Donors with Diabetes (nPOD) has allowed characterization of pathways leading to this inflammation.

OBJECTIVE:

12-Lipoxygenase (12-LO) induces inflammation and has been implicated in diabetes development. Our goal was to determine expression of 12-LO in human islets from control, autoantibody-positive, type 1 diabetic, and type 2 diabetic nPOD pancreas donors.

DESIGN:

Pancreas tissues from nPOD donors were examined by immunohistochemistry and immunofluorescence for islet expression of 12-LO in different subsets of islet cells.

PARTICIPANTS:

Donor pancreas samples were obtained from nPOD based on disease status (control, n = 7; autoantibody-positive, n = 8; type 1 diabetic, n = 17; or type 2 diabetic donors, n = 15).

MAIN OUTCOME MEASURE:

Determination of 12-LO expression within human islets served as the main outcome measure, including distinguishing which types of islet cells expressed 12-LO.

RESULTS:

Islets from control participants (nondiabetic) lacked islet expression of 12-LO. Of donors in the other groups, 25% to 37% expressed islet 12-LO with a clear inverse relation between the numbers of β-cells and 12-LO(+) cells within islets of 12-LO(+) cases. 12-LO expression was not seen within macrophages, endothelial cells, α-cells, or β-cells, but only within cells expressing low levels of pancreatic polypeptide (PP) and increased levels of vimentin.

CONCLUSIONS:

12-LO expression colocalizes within a specific type of islet PP(+) cell under prediabetic and diabetic conditions. The costaining of PP and vimentin suggests that 12-LO participates in the process leading to β-cell dedifferentiation in the islet.

• Authors: Wojciech J Grzesik, Joseph L Nadler, Yui Machida, Jerry L Nadler, Yumi Imai, Margaret A Morris
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 100 Issue 3 Pg. E387-95 (Mar 2015) ISSN: 1945-7197 [Electronic] United States
• PMID: 25532042 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Autoantibodies
• Vimentin
• Pancreatic Polypeptide
• Arachidonate 12-Lipoxygenase

Topics

• Arachidonate 12-Lipoxygenase (genetics, metabolism)
• Autoantibodies (metabolism)
• Cell Dedifferentiation (genetics)
• Diabetes Mellitus, Type 1 (genetics, metabolism, pathology)
• Diabetes Mellitus, Type 2 (genetics, metabolism, pathology)
• Gene Expression Regulation, Enzymologic
• Humans
• In Situ Hybridization, Fluorescence
• Islets of Langerhans (metabolism, pathology)
• Pancreas Transplantation
• Pancreatic Polypeptide (metabolism)
• Tissue Donors
• Vimentin (metabolism)