Lipopolysaccharide-induced suppression of periodontal ligament cell proliferation and apoptosis are strengthened under high glucose conditions.

•Primary cultures of human PDL cells were prepared from extracted teeth of patients.•LPS-induced suppression of cell proliferation were strengthened by high glucose.•LPS-induced cell apoptosis were strengthened under high glucose condition.•LPS-induced decrease in Bcl-2/Bax ratio were strengthened by high glucose.•Glucose and LPS had a significant interaction for cell apoptosis.