Chemokine Expression Is Upregulated in Chondrocytes in Diabetic Fracture Healing

Loading...
Thumbnail Image
Penn collection
Departmental Papers (Dental)
Degree type
Discipline
Subject
Animals
Chemokines
Chondrocytes
Diabetes Mellitus
Experimental
Fracture Healing
Immunohistochemistry
Mice
RNA Interference
RNA
Messenger
Up-Regulation
Amino Acids, Peptides, and Proteins
Dentistry
Endocrinology, Diabetes, and Metabolism
Osteopathic Medicine and Osteopathy
Funder
Grant number
License
Copyright date
Distributor
Related resources
Author
Alblowi, Jazia
Tian, Chen
Kayal, Rayyan A
McKenzie, Erin
Behl, Yugal
Gerstenfeld, Louis
Einhorn, Thomas A
Contributor
Abstract

Chemokines are thought to play an important role in several aspects of bone metabolism including the recruitment of leukocytes and the formation of osteoclasts. We investigated the impact of diabetes on chemokine expression in normal and diabetic fracture healing. Fracture of the femur was performed in streptozotocin-induced diabetic and matched normoglycemic control mice. Microarray analysis was carried out and chemokine mRNA levels in vivo were assessed. CCL4 were examined in fracture calluses by immunohistochemistry and the role of TNF in diabetes-enhanced expression was investigated by treatment of animals with the TNF-specific inhibitor, pegsunercept. In vitro studies were conducted with ATDC5 chondrocytes. Diabetes significantly upregulated mRNA levels of several chemokines in vivo including CCL4, CCL8, CCL6, CCL11, CCL20, CCL24, CXCL2, CXCL5 and chemokine receptors CCR5 and CXCR4. Chondrocytes were identified as a significant source of CCL4 and its expression in diabetic fractures was dependent on TNF (P < 0.05). TNF-α significantly increased mRNA levels of several chemokines in vitro which were knocked down with FOXO1 siRNA (P < 0.05). CCL4 expression at the mRNA and proteins levels was induced by FOXO1 over-expression and reduced by FOXO1 knockdown. The current studies point to the importance of TNF-α as a mechanism for diabetes enhanced chemokine expression by chondrocytes, which may contribute to the accelerated loss of cartilage observed in diabetic fracture healing. Moreover, in vitro results point to FOXO1 as a potentially important transcription factor in mediating this effect.

Advisor
Date Range for Data Collection (Start Date)
Date Range for Data Collection (End Date)
Digital Object Identifier
Series name and number
Publication date
2013-03-01
Journal title
Bone
Volume number
Issue number
Publisher
Publisher DOI
Journal Issue
Comments
Recommended citation
Collection