Proliferative Effect of Proanthocyanidins on HGF-1 and HPDLF Cells: An In Vitro Study

<i>Background and Objectives:</i> The use of proanthocyanidins (PACNs) alongside standard periodontal treatment procedures can improve periodontal and peri-implant tissue healing. The present study aimed to evaluate the effect of different concentrations of <i>Pelargonium sidoides</i> root extract (PSRE) on periodontal tissue proliferation in comparison with chlorhexidine digluconate (CHX). <i>Materials and Methods</i>: A cell culture study was performed using human gingival fibroblast (HGF-1) and human periodontal ligament fibroblast (HPDLF) lines. The HGF-1 cell line was exposed to CHX (the gold standard treatment in periodontal diseases) and PSRE at concentrations of up to 800 μg/mL, which were compared with negative controls. HGF-1 viability and proliferation were evaluated using fluorescence tests and the PrestoBlue assay, respectively. In addition, the cell proliferation induction ability of PSRE was evaluated by treating HGF-1 and HPDLF cells with PSRE at 25 and 50 μg/mL concentrations and measuring the TGFβ-1 levels using TGFβ-1 ELISA. <i>Results</i>: When comparing the effects of the 25 μg/mL PSRE treatment to the control, a statistically significant difference in HGF-1 cell growth was observed (0.297 ± 0.048 (mean ± SE) and 0.203 ± 0.01, respectively; <i>p</i> = 0.006). The strongest cytotoxic effect on HGF-1 cells was observed with CHX (0.007 ± 0.006, <i>p</i> < 0.001 vs. control). The HGF-1 and HPDLF cells showed statistically significant increases in TGFβ-1 levels when treated with PSRE at 25 and 50 μg/mL compared with the control (352.38 ± 31.32 (mean ± SE) and 330.99 ± 26.53 versus 161.07 ± 15.11 in HGF-1 cells; 397.53 ± 18.1 and 399.91 ± 27.61 versus 137.7 ± 16.54 in HPDLF cells, <i>p</i> < 0.001). Additionally, no negative effects were detected at low PSRE concentrations (less than 100 μg/mL). <i>Conclusions</i>: The results of this study suggested that PACNs may promote HGF-1 and HPDLF cell proliferation. In contrast, CHX showed cytotoxic effects.