Collagen type I prevents glyoxal-induced apoptosis in osteoblastic cells cultured on titanium alloy.

Abstract

Advanced glycation end products (AGEs) irreversibly cross-link proteins with sugars and accumulate at a higher age and in diabetes, processes which can interfere with the integration of implants into the tissue. Glyoxal is a highly reactive glycating agent involved in the formation of AGEs and is known to induce apoptosis, as revealed by the upregulation of caspase-3 and fractin (caspase-3 being a key enzyme activated during the late stage of apoptosis and fractin being a caspase-cleaved actin fragment). In this study, we investigated the influence of collagen type I coating on the cytotoxic effect of glyoxal on rat calvarial osteoblastic cells and on human osteosarcoma cells (Saos-2) grown on titanium alloy, Ti6Al4V. Activation of caspase-3 and fractin was measured by counting immunohistochemically stained cells and by flow cytometry with propidium iodide (detection of the apoptosis indicating a sub-G1 peak). Our results showed an increased number of apoptotic osteoblasts after incubation with glyoxal on Ti6Al4V discs. However, the number of apoptotic cells on collagen-coated titanium was significantly smaller than on uncoated titanium after the same treatment. The present findings demonstrate that osteoblasts treated with glyoxal undergo apoptosis, whereas collagen type I coating of titanium alloys (used for implants) has an antiapoptotic function.

• Authors: S Tippelt, C Ma, M Witt, S Bierbaum, R H W Funk
• Journal: Cells, tissues, organs (Cells Tissues Organs) Vol. 177 Issue 1 Pg. 29-36 ( 2004) ISSN: 1422-6405 [Print] Switzerland
• PMID: 15237193 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright 2004 S. Karger AG, Basel

Chemical References

• Alloys
• Chromatin
• Collagen Type I
• Cross-Linking Reagents
• Glycation End Products, Advanced
• Glyoxal
• Titanium
• CASP3 protein, human
• Casp3 protein, rat
• Caspase 3
• Caspases

Topics

• Alloys (pharmacology)
• Animals
• Apoptosis
• Caspase 3
• Caspases (metabolism)
• Cell Culture Techniques (methods)
• Cell Line
• Cell Line, Tumor
• Cells, Cultured
• Chromatin (metabolism)
• Collagen Type I (physiology)
• Cross-Linking Reagents (pharmacology)
• Dose-Response Relationship, Drug
• Glycation End Products, Advanced (metabolism)
• Glyoxal (pharmacology)
• Humans
• Immunohistochemistry
• Microscopy, Fluorescence
• Osteoblasts (metabolism, pathology)
• Osteosarcoma (metabolism)
• Rats
• Time Factors
• Titanium (pharmacology)
• Up-Regulation