Cytotoxicity, Genotoxicity and Cytokines Modulation of N-acetylcysteine, Calcium Hydroxide, Chlorhexidine and their Combinations

This study aimed to evaluate the cytotoxicity, genotoxicity and effect on cytokine production of n-acetylcysteine (NAC), calcium hydroxide [Ca(OH)₂], chlorhexidine (CHX) and their combinations on murine macrophage cells (RAW 264.7) and human osteoblasts-like cells (MG-63). Cytotoxicity was evaluated by MTT colorimetric assay after 5 min and 24 h. Genotoxicity evaluation was evaluated by cytokinesis-block micronucleus assay. In addition, cytometry bead arrays to quantify different cytokine production by RAW 264.7 and MG63 cells. Data were statistically analyzed with a significant level of α ≤ 0.05. All medications promoted high cellular viability of RAW 264.7 after 5 min, and of MG63 after 24h. All medications presented a low number of micronuclei except for CHX in Raw 264.7. NAC was highlighted as it stimulates high production of IL-12p70, IL-6, and IFN-γ in RAW 264.7 cells, in addition to IL-12p70, TNF-α, IL-10, IL-6, and IL-1β in MG63. Therefore, NAC demonstrated a potential immunomodulatory effect by promoting a balance between pro-inflammatory activation and regulatory cytokine responses.