The volatile fraction of cigarette smoke induces alterations in the human gingival fibroblast cytoskeleton

Several in vitro investigations have indicated that the particulate phase of cigarette smoke, such as nicotine, affects many cell types, including gingival fibroblasts. However, few studies have been performed on the effects of the volatile fraction on the cellular structures that are involved in cell functions, such as adhesion and proliferation. Since the survival and reproduction of gingival fibroblasts are fundamental in maintaining the integrity of the oral connective tissue, as well as in wound healing, the effects on the cytoskeleton of acrolein and acetaldehyde, which are the volatile fractions of cigarette smoke, were examined in vitro for human gingival fibroblasts (HGFs). HGF strains that were taken from healthy subjects with non-inflamed-gingiva were utilized in this investigation. The cells were incubated in the presence of different concentrations of acrolein and acetaldehyde. Cell adhesion and viability were evaluated after incubation for 3 h and 5 days, respectively. The influence on cytoskeletal structures (tubulin, actin and vimentin intermediate filaments) was investigated with the indirect immunofluorescence technique. The results show that both substances produced similar effects, which resulted in a dose-dependent inhibition of HGF adhesion and viability. Disturbance of the HGF cytoskeleton consisted of disruption of the microtubules, actin filaments and vimentin microfilaments, which was accompanied by alterations to cell shape. Our experimental findings suggest that the volatile fractions of cigarette smoke, such as acrolein and acetaldehyde, have a cytotoxic effect on HGFs, with the result that they lose their capacity for adhesion and proliferation. The consequences of this could be impairment of the maintenance, integrity and remodelling of the oral connective tissue. According to our morphological evidence, these findings show that cigarette smoke can lead to the development and progression of periodontal disease, and indicate the need for appropriate therapy.