Apoptotic genes are differentially expressed in aged gingival tissue.
O A González1, A J Stromberg, P M Huggins
1Center for Oral Health Research, College of Dentistry, Department of Statistics, University of Kentucky, Lexington, KY 40536-0305, USA. ogonz2@email.uky.edu
Journal of Dental Research
|April 8, 2011
Summary
Aging impacts cellular processes in the periodontium, altering apoptotic gene expression. This study reveals distinct apoptotic pathway involvement in periodontal disease in adult versus aged non-human primates.
Area of Science:
- Oral biology
- Cellular and molecular biology
- Gerontology
Background:
- Aging is linked to increased oral disease prevalence, yet cellular changes in the periodontium remain understudied.
- Impaired apoptosis (programmed cell death) in aging may contribute to chronic inflammatory conditions like periodontitis.
Purpose of the Study:
- To investigate alterations in apoptotic gene expression in healthy and periodontitis-affected gingival tissues across different age groups.
- To understand the role of aging in the molecular mechanisms underlying periodontal disease.
Main Methods:
- Gene expression analysis of 88 apoptotic pathway genes using the GeneChip® Rhesus Macaque Genome Array.
- Comparison of gingival biopsies from young, adult, and aged non-human primates (Macaca mulatta) in healthy and periodontitis states.
Main Results:
- Healthy young gingival tissue showed lower anti-apoptotic and higher pro-apoptotic gene expression compared to aged tissue.
- Minimal gene expression differences were found in healthy gingival tissue between adult and aged animals.
- Apoptotic gene regulation in diseased gingival tissue differed between adult and aged groups.
Conclusions:
- Apoptotic processes in gingival tissues may be reduced during aging.
- Distinct apoptotic pathway mechanisms are potentially involved in periodontal disease pathophysiology, varying between adult and aged individuals.
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