Biocompatibility and inflammatory response of silver tungstate, silver molybdate, and silver vanadate microcrystals

Silver tungstate (alpha-Ag2WO4), silver molybdate (beta-Ag2MoO4), and silver vanadate (alpha-AgVO3) microcrystals have shown interesting antimicrobial properties. However, their biocompatibility is not yet fully understood. Cytotoxicity and the inflammatory response of silver-containing microcrystals were analyzed in THP-1 and THP-1 differentiated as macrophage-like cells, with the alamarBlue (TM) assay, flow cytometry, confocal microscopy, and ELISA. The present investigation also evaluated redox signaling and the production of cytokines (TNF alpha, IL-1 beta, IL-6, and IL-8) and matrix metalloproteinases (MMP-8 and -9). The results showed that alpha-AgVO3 (3.9 mu g/mL) did not affect cell viability (p > 0.05). alpha-Ag2WO4 (7.81 mu g/mL), beta-Ag2MoO4 (15.62 mu g/mL), and alpha-AgVO3 (15.62 mu g/mL) slightly decreased cell viability (p <= 0.003). All silver-containing microcrystals induced the production of O-2(-) and this effect was mitigated by Reactive Oxygen Species (ROS) scavenger and N-acetylcysteine (NAC). TNF alpha, IL-6 and IL-1 beta were not detected in THP-1 cells, while their production was either lower (p <= 0.0321) or similar to the control group (p >= 0.1048) for macrophage-like cells. The production of IL-8 by both cellular phenotypes was similar to the control group (p >= 0.3570). The release of MMP-8 was not detected in any condition in THP-1 cells. Although MMP-9 was released by THP-1 cells exposed to alpha-AgVO3 (3.9 mu g/mL), no significant difference was found with control (p = 0.7). Regarding macrophage-like cells, the release of MMP-8 and -9 decreased in the presence of all microcrystals (p <= 0.010). Overall, the present work shows a promising biocompatibility profile of, alpha-Ag2WO4, beta-Ag2MoO4, and alpha-AgVO3 microcrystals.

Automated summary

Silver tungstate (alpha-Ag2WO4), silver molybdate (beta-Ag2MoO4), and silver vanadate (alpha-AgVO3) microcrystals exhibit interesting antimicrobial properties, but their biocompatibility is not fully understood. This study analyzed the cytotoxicity and inflammatory response of silver-containing microcrystals in different cell models and evaluated the production of cytokines and matrix metalloproteinases. The results showed promising biocompatibility profiles for alpha-Ag2WO4, beta-Ag2MoO4, and alpha-AgVO3 microcrystals.