Assessment of Collagen Metabolism by Human Gingival Fibroblasts Reared in Serum‐free Conditions

Abstract

Periodontal disease is present in 48% of people over the age of 30 years and 70% over the age of 65 years. It is marked by an inflammatory state that affects the gum tissue, periodontal ligaments, and the alveolar bone itself. It has several different causes, but a significant risk factor is smoking because it impairs the healthy biological pathway of repair of the tissues. In a generally healthy patient, there is a balance of broken down collagen and repair with intact collagen. The enzyme responsible for this collagen type 1 degradation is matrix metalloproteinase‐8 (MMP‐8). In this study, the metabolic activity of primary human gingival fibroblasts (HGVF) isolated from inflamed non‐smoker (IFN) and inflamed smoker (IFC) were cultured in serum‐free media over a 48 hour period. We measured production of intact and degraded collagen type I in the secreted fraction (conditioned media) and in the incorporated extracellular matrix. In the secreted and incorporated fractions at both time points (24 and 48hr), HGVF isolated from a smoker (IFC) produced more intact collagen (100% more secreted and incorporated) and more degraded collagen (97% more secreted and 95% more incorporated) than HGVF isolated from the non‐smoker (IFN) (p<0.001). These data support the hypothesis that inflamed tissue isolated from a current smoker exhibits a profile of collagen metabolism in line with more acute diseased state (fibrotic collagen profile). In addition, the culture of primary human gingival fibroblasts in serum‐free medium for at least 48 hours is a viable method to study the disease mechanism of periodontitis and potential therapeutics to treat the disease.Support or Funding InformationThis work is supported by the Division of Research at PCOM