Mupirocin reduces ciliary beat frequency of human nasal epithelial cells

Impact of Bepanthen® and dexpanthenol on human nasal ciliary beat frequency in vitro

BACKGROUND

Dexpanthenol-containing ointments/fluids are recommended to restore impaired nasal mucosa. To date, there are no data about the influence of dexpanthenol or formulations including dexpanthenol on ciliary beat frequency (CBF) of nasal epithelial cells.

METHODS

We tested the ciliary beat frequency of human nasal epithelial cells in RPMI 1640 cell solution using in vitro high-frequency video microscopy every 60 s over a period of 15 min (min). Bepanthen^® solution and dexpanthenol in two clinically relevant concentrations (1.67% and 3.33%) were added to the cells. Addition of sterile water served as control group. To get a better overview, the measurements after 1 min, 5 min and 15 min were combined.

RESULTS

The CBF in the control group (n = 17) after 15 min was 7.3 ± 2.6 Hz. In comparison, the CBF after 15 min was 1.8 ± 1.0 Hz in the 3.33% Bepanthen^® group (n = 17) and 3.2 ± 1.2 Hz in the 1.67% group, which was statistically significantly lower in both groups (p < 0.001). With regard to the dexpanthenol group (n = 17) a CBF of 6.0 ± 2.6 Hz with 3.33% and 6.1 ± 2.4 Hz with 1.67% dexpanthenol, was detected, which was again statistically significantly lower (p = 0.06) compared to the control group except CBF at 15 min with 1.57% (n = 17; p = 0.04). In general, the effect on CBF was less pronounced with dexpanthenol compared with Bepanthen^® with a statistically significant difference between the two formulations. The results were verified by calculating an analysis of variance (ANOVA).

CONCLUSIONS

Bepanthen^® as an ointment, solution or inhalation is commonly used in ENT for mucosal care. Our results have shown that both substances reduce CBF in clinically relevant concentrations, although the effect was more pronounced with Bepanthen^® compared to dexpanthenol solution, which could be related to additives or change of physical properties in the solution. Further research is needed to assess potential clinical relevance.

Effects of tranexamic acid on human nasal ciliary beat frequency

Background

Patients with recurrent epistaxis, particularly due to hereditary hemorrhagic telangiectasia (HHT) are recommended to apply topical tranexamic acid (TXA) to reduce bleeding events. Those patients may suffer ciliary dysfunction due to TXA’s effects on ciliary beating frequency (CBF) and their consequences.

Methodology/principal

Human nasal epithelial cells were harvested with a nasal brush in 30 healthy subjects. We investigated the CBF in RPMI medium using high-frequency video microscopy. TXA was added to the cells in various concentrations ranging from 2 to 5%, including the therapeutic concentration (2%) and a control (0%).

Results

CBF in the control condition was 6.1 ± 1.6 Hz. TXA reduces CBF in a time and concentration dependent manner, to, e.g. 4.3 ± 1.2 Hz with 2% TXA and 3.3 ± 0.9 Hz with 5% TXA after 16–20 min. The differences in CBF were statistically significant for all concentrations of TXA.

Conclusions

TXA has the potential to significantly impair nasal epithelial function. Therefore, frequent or regular topical nasal application of TXA should be done under close monitoring of nasal function, especially in patients with co-morbidities like chronic rhinosinusitis.

Tolerability and effectiveness of povidone-iodine or mupirocin versus saline sinus irrigations for chronic rhinosinusitis

OBJECTIVES

The role of topical anti-infectives in acute exacerbations of chronic rhinosinusitis is controversial. Povidone-iodine is an anti-bacterial and anti-viral that is affordable and available over-the-counter and may demonstrate advantages over mupirocin as a sinus irrigation therapy. The objective was to compare povidone-iodine or mupirocin versus saline sinus irrigations for sinusitis exacerbations in post-surgery subjects as well as to assess tolerability of povidone-iodine sinus irrigations.

MATERIALS AND METHODS

This was a prospective single-blinded (clinician only) randomized controlled trial. Subjects were post-surgery with acute exacerbations of chronic rhinosinusitis and gram-positive bacteria on culture. They received povidone-iodine, mupirocin, or saline sinus irrigations, twice daily for 30 days. Outcomes were post-treatment culture negativity (primary) and Sinonasal Outcome Test-20 and Lund-Kennedy endoscopic score change (secondary).

RESULTS

Of the 62 subjects analyzed, post-treatment culture negativity rate was higher in the MUP (14/20, 70%) group compared to the PI (9/21, 43%) and SAL (9/19, 47%) groups, although this was not significant (p = 0.29). Povidone-iodine sinus irrigations at the 1% concentration were very well-tolerated, similar to saline irrigations. There were no significant differences in Sinonasal Outcome Test-20 score (povidone-iodine -0.3 [-0.6, 0.05] vs. mupirocin -0.3 [-0.7, 0.05] vs. saline -0.4 [-0.8, 0.05]; p = 0.86) or Lund-Kennedy endoscopic score (povidone-iodine -3.5 [-7, -0.5] vs. mupirocin -2 [-4, 2] vs. saline -3 [-5, 0]; p = 0.45) change. No serious adverse effects were reported.

CONCLUSIONS

In patients who have had prior sinus surgery with acute exacerbations of CRS and gram-positive bacteria on culture, mupirocin sinus irrigations achieved a better post-treatment culture "control" rate compared to saline and povidone-iodine. In addition, 1% povidone-iodine solution was well-tolerated as a sinus irrigation and may represent a feasible method for temporarily disinfecting the sinonasal cavity of bacteria and viruses such as COVID-19.

Influence of Intranasal Drugs on Human Nasal Mucociliary Clearance and Ciliary Beat Frequency

The nasal mucociliary clearance system, which comprises epithelial cilia and mucus from goblet cells, is an important intrinsic defense mechanism of the upper respiratory tract. Intranasal drugs and additives can have a detrimental effect on ciliary activity and mucociliary clearance, and thus impact the integrity of nasal defense mechanisms. This article discusses the current literature on the effects of different classes of intranasal drugs including intranasal corticosteroids, antihistamines, decongestants, antimicrobials and antivirals, as well as various drug excipients and nasal irrigation solutions on human nasal mucociliary clearance and ciliary beat frequency. Available data indicate that some intranasal formulations tend to hamper nasal ciliary function and mucociliary clearance. Therefore, it is of great importance to assess the effects of intranasal drugs and additives on mucociliary function before they are recommended as therapy for different nasal conditions.