Is tannic acid a promising option in local treatment of nasal diseases?

OBJECTIVE: We investigated the effects of tannic acid on viability and proliferation of nasal cells after topical application. It was also evaluated whether tannic acid served as an alternative treatment agent. MATERIALS AND METHODS: Collected primary nasal epithelium from healthy people who had undergone septoplasty operations were incubated in cell culture. Following the implementation of 2.5 µM tannic acid in cultured cells, both the number of total cells and their viability were measured using the trypan blue assay, while proliferation was assessed through the XTT method. The XTT method, which involves using "2,3-bis-(2-methoxy-4-nitro-5-sulphophenyl)-2H-tetrazolium-5-carboxanilide", is a reliable means of determining cellular toxicity. RESULTS: XTT experiment results showed that there was no harm was detected to nasal cells after tannic acid's topical implementation. There were no significant changes in cell proliferation; moreover, no matter what the doses were. Additionally, no cytotoxic effects were detected on nasal cells' primary culture at "the end of the 24 hours of implementation". There was no side effect of it, either. CONCLUSIONS: According to the research, the application of tannic acid topically did not result in any harmful effects on the nasal cell culture. Tannic acid's potential anti-inflammatory properties and its ability to decrease Th2-related cytokines suggest that it may be beneficial for patients with rhinosinusitis or allergic rhinitis, pending confirmation through clinical trials. Additionally, if clinical trials confirm its effectiveness, tannic acid may be useful in healing wounds for patients undergoing septorhinoplasty.