Nasal polyps show decreased mucociliary transport despite vigorous ciliary beating.

OBJECTIVE: Mucociliary transport function in the airway mucosa is essential for maintaining a clean mucosal surface. This function is impaired in upper and lower airway diseases. Nasal polyps are a noticeable pathological feature that develop in some of the patients with chronic rhinosinusitis. Like ordinary nasal mucosae, nasal polyps have a ciliated pseudostratified epithelium with vigorous ciliary beating. We measured ex vivo Mucociliary Transport Velocity (MCTV) and Ciliary Beat Frequency (CBF) and explored the expressions of Planar Cell Polarity (PCP) proteins in nasal polyps in comparison with turbinate mucosae. METHODS: Inferior turbinates and nasal polyps were surgically collected from patients with chronic rhinosinusitis. Ex vivo MCTV and CBF were measured using a high-speed digital imaging system. Expressions of PCP proteins were explored by fluorescence immunohistochemistry and quantitative RT-PCR. RESULTS: The MCTV of nasal polyps was significantly lower than that of the turbinates (7.43 ±â€¯2.01 vs. 14.56 ±â€¯2.09 µm/s; p = 0.0361), whereas CBF did not differ between the two tissues. The MCTV vector was pointed to the posteroinferior direction in all turbinates with an average inclination angle of 41.0 degrees. Immunohistochemical expressions of Dishevelled-1, Dishevelled-3, Frizzled3, Frizzled6, Prickle2 and Vangl2 were lower in the nasal polyps than in the turbinates. Confocal laser scanning microscopy showed that Frizzled3 was localized along the cell junction on the apical surface. The expression levels of mRNAs for Dishevelled-1, Dishevelled-3 and Frizzled3 in the nasal polyps were also decreased in comparison with the turbinates. CONCLUSION: These results indicate that muco ciliary transport in nasal polyps is impaired although vigorous ciliary beating is maintained, and that the impairment may be caused by a decrease in Dishevelled/Frizzled proteins and resultant PCP disarrangement. LEVEL OF EVIDENCE: Level 3.

Nasal polyps show decreased mucociliary transport despite vigorous ciliary beating

Abstract Objective Mucociliary transport function in the airway mucosa is essential for maintaining a clean mucosal surface. This function is impaired in upper and lower airway diseases. Nasal polyps are a noticeable pathological feature that develop in some of the patients with chronic rhinosinusitis. Like ordinary nasal mucosae, nasal polyps have a ciliated pseudostratified epithelium with vigorous ciliary beating. We measured ex vivo Mucociliary Transport Velocity (MCTV) and Ciliary Beat Frequency (CBF) and explored the expressions of Planar Cell Polarity (PCP) proteins in nasal polyps in comparison with turbinate mucosae. Methods Inferior turbinates and nasal polyps were surgically collected from patients with chronic rhinosinusitis. Ex vivo MCTV and CBF were measured using a high-speed digital imaging system. Expressions of PCP proteins were explored by fluorescence immunohistochemistry and quantitative RT-PCR. Results The MCTV of nasal polyps was significantly lower than that of the turbinates (7.43 ± 2.01 vs. 14.56 ± 2.09 μm/s; p= 0.0361), whereas CBF did not differ between the two tissues. The MCTV vector was pointed to the posteroinferior direction in all turbinates with an average inclination angle of 41.0 degrees. Immunohistochemical expressions of Dishevelled-1, Dishevelled-3, Frizzled3, Frizzled6, Prickle2 and Vangl2 were lower in the nasal polyps than in the turbinates. Confocal laser scanning microscopy showed that Frizzled3 was localized along the cell junction on the apical surface. The expression levels of mRNAs for Dishevelled-1, Dishevelled-3 and Frizzled3 in the nasal polyps were also decreased in comparison with the turbinates. Conclusion These results indicate that muco ciliary transport in nasal polyps is impaired although vigorous ciliary beating is maintained, and that the impairment may be caused by a decrease in Dishevelled/Frizzled proteins and resultant PCP disarrangement. Level of evidence: Level 3.

Temperature effect on the maximum swimming speed of jack mackerelTrachurus japonicus through muscle contraction monitoring

The purpose of this study is to know the effect of temperature on fish muscle contraction of jack mackerel (Trachurus japonicus), which muscle contraction will determine the tail beat frequency and maximum swimming speed. The maximum swimming speed of was evaluated according to the measurement of the muscle contraction time with electric stimuli of 2-7 V, 50 ms. Fish were separated into four groups for temperature acclimation at 10, 15, 18 and 22ºC to reflect typical changes in seasonal water temperature in Japan. Results showed that the swimming speed of the fish was positively related to the tail-beat frequency at all temperatures. The muscle contraction time was also affected by the acclimated temperature, which longer at the lower temperature than higher ones. Mean contraction time (Tm) was 45.1 ms at 10 ºC, 32.7 ms at 15 ºC, 32.9 ms at 18 ºC, and 31.9 ms at 22 ºC, respectively. The mean of maximum tail-beat frequency (Fmax) obtained from Fmax = ½ Tm was 11.4 Hz at 10 ºC, 15.8 Hz at 15 ºC, 16,4 Hz at 18 ºC, and 16.6 Hz at 22 ºC. These were used to estimate the maximum swimming speed (Umax) at each temperature, resulting in 9.45 FL s-¹ at 10 ºC, 13.5 FL s-¹ at 15 ºC, 14.0 FL s-¹ 18 ºC, and 14.2 FL s-¹ at 22 ºC. The seasonal temperature effects on the swimming performance of T. japonicus, which lower water temperature in the winter made low swimming performance.

Temperature effect on the maximum swimming speed of jack mackerelTrachurus japonicus through muscle contraction monitoring

The purpose of this study is to know the effect of temperature on fish muscle contraction of jack mackerel (Trachurus japonicus), which muscle contraction will determine the tail beat frequency and maximum swimming speed. The maximum swimming speed of was evaluated according to the measurement of the muscle contraction time with electric stimuli of 2-7 V, 50 ms. Fish were separated into four groups for temperature acclimation at 10, 15, 18 and 22ºC to reflect typical changes in seasonal water temperature in Japan. Results showed that the swimming speed of the fish was positively related to the tail-beat frequency at all temperatures. The muscle contraction time was also affected by the acclimated temperature, which longer at the lower temperature than higher ones. Mean contraction time (Tm) was 45.1 ms at 10 ºC, 32.7 ms at 15 ºC, 32.9 ms at 18 ºC, and 31.9 ms at 22 ºC, respectively. The mean of maximum tail-beat frequency (Fmax) obtained from Fmax = ½ Tm was 11.4 Hz at 10 ºC, 15.8 Hz at 15 ºC, 16,4 Hz at 18 ºC, and 16.6 Hz at 22 ºC. These were used to estimate the maximum swimming speed (Umax) at each temperature, resulting in 9.45 FL s-¹ at 10 ºC, 13.5 FL s-¹ at 15 ºC, 14.0 FL s-¹ 18 ºC, and 14.2 FL s-¹ at 22 ºC. The seasonal temperature effects on the swimming performance of T. japonicus, which lower water temperature in the winter made low swimming performance.(AU)

An autocrine ATP release mechanism regulates basal ciliary activity in airway epithelium.

KEY POINTS: Extracellular ATP, in association with [Ca2+ ]i regulation, is required to maintain basal ciliary beat frequency. Increasing extracellular ATP levels increases ciliary beating in airway epithelial cells, maintaining a sustained response by inducing the release of additional ATP. Extracellular ATP levels in the millimolar range, previously associated with pathophysiological conditions of the airway epithelium, produce a transient arrest of ciliary activity. The regulation of ciliary beat frequency is dependent on ATP release by hemichannels (connexin/pannexin) and P2X receptor activation, the blockage of which may even stop ciliary movement. The force exerted by cilia, measured by atomic force microscopy, is reduced following extracellular ATP hydrolysis. This result complements the current understanding of the ciliary beating regulatory mechanism, with special relevance to inflammatory diseases of the airway epithelium that affect mucociliary clearance. ABSTRACT: Extracellular nucleotides, including ATP, are locally released by the airway epithelium and stimulate ciliary activity in a [Ca2+ ]i -dependent manner after mechanical stimulation of ciliated cells. However, it is unclear whether the ATP released is involved in regulating basal ciliary activity and mediating changes in ciliary activity in response to chemical stimulation. In the present study, we evaluated ciliary beat frequency (CBF) and ciliary beating forces in primary cultures from mouse tracheal epithelium, using videomicroscopy and atomic force microscopy (AFM), respectively. Extracellular ATP levels and [Ca2+ ]i were measured by luminometric and fluorimetric assays, respectively. Uptake of ethidium bromide was measured to evaluate hemichannel functionality. We show that hydrolysis of constitutive extracellular ATP levels with apyrase (50 U ml-1 ) reduced basal CBF by 45% and ciliary force by 67%. The apyrase effect on CBF was potentiated by carbenoxolone, a hemichannel inhibitor, and oxidized ATP, an antagonist used to block P2X7 receptors, which reduced basal CBF by 85%. Additionally, increasing extracellular ATP levels (0.1-100 µm) increased CBF, maintaining a sustained response that was suppressed in the presence of carbenoxolone. We also show that high levels of ATP (1 mm), associated with inflammatory conditions, lowered basal CBF by reducing [Ca2+ ]i and hemichannel functionality. In summary, we provide evidence indicating that airway epithelium ATP release is the molecular autocrine mechanism regulating basal ciliary activity and is also the mediator of the ciliary response to chemical stimulation.

Chemical composition modulates the adverse effects of particles on the mucociliary epithelium

OBJECTIVE:We compared the adverse effects of two types of real ambient particles; i.e., total suspended particles from an electrostatic precipitator of a steel mill and fine air particles from an urban ambient particulate matter of 2.5 µm, on mucociliary clearance.METHOD:Mucociliary function was quantified by mucociliary transport, ciliary beating frequency and the amount of acid and neutral mucous in epithelial cells through morphometry of frog palate preparations. The palates were immersed in one of the following solutions: total suspended particles (0.1 mg/mL), particulate matter 2.5 µm 0.1 mg/mL (PM0.1) or 3.0 mg/mL (PM3.0) and amphibian Ringer’s solution (control). Particle chemical compositions were determined by X-ray fluorescence and gas chromatography/mass spectrometry.RESULTS:Exposure to total suspended particles and PM3.0 decreased mucociliary transport. Ciliary beating frequency was diminished by total suspended particles at all times during exposure, while particulate matter of 2.5 µm did not elicit changes. Particulate matter of 2.5 µm reduced epithelial mucous and epithelium thickness, while total suspended particles behaved similarly to the control group. Total suspended particles exhibited a predominance of Fe and no organic compounds, while the particulate matter 2.5 µm contained predominant amounts of S, Fe, Si and, to a lesser extent, Cu, Ni, V, Zn and organic compounds.CONCLUSION:Our results showed that different compositions of particles induced different airway epithelial responses, emphasizing that knowledge of their individual characteristics may help to establish policies aimed at controlling air pollution.

TNF alfa modifica la respuesta de la frecuencia de batido ciliar a la carga viscosa, asociado a alteraciones en el calcio intracelular en células ciliadas respiratorias humanas / TNF alpha modifies ciliary beat frequency in response to viscous overload, associated to changes in intracellular calcium in human respiratory ciliated cells

Introducción: Secreciones sinonasales patológicas y elevados niveles de factor de necrosis tumoral alfa (TNF alfa) se han encontrado en mucosa sin usal de pacientes con sinusitis crónica. Las células ciliadas respiratorias tienen una reserva funcional que les permite autorregular su frecuencia de batido ciliar (FBC) en respuesta a cambios en la viscosidad, modificando los niveles de calcio intraacelular [Ca+²]ic. Objetivo: Nuestro objetivo es determinóar si TNFalfa afecta el mecanismo de autorregulación y la homeostasis del calcio intraacelular frente a cambios en la viscosidad. Material y método: Cultivos primarios de explantes de tejido adenoideo. Registro de FBC mediante microfotodensitometría. Cultivos tratados con TNFalfa (10 ng/ml) o control durante 24 y 48 horas. Se in crementó la viscosidad agregando dextrano 500 al 10 por ciento y 20 por ciento. Se midió [Ca+²]ic en células cargadas con Fura 2AM. Resultados: El tratamiento con TNFalfa por 48 horas produjo una significativa disminución de la FBC a baja viscosidad, aumento significativo de [Ca+²]ic y caída mayor de FBC en cultivos tratados con tapsigargina (bloqueador bomba calcio-ATPasa retículo). in o se encontró diferencia a alta viscosidad. Conclusión: Después de 48 horas de exposición a TNFalfa se observa un efecto negativo en el mecanismo de adaptación de las células ciliadas a un medio con baja viscosidad, probablemente secundario a cambios en la homeostasis del [Ca+²]ic.

Introduction: Pathologic sinonasal secretions and elevated levels of tumor necrosis factor alpha (TNFalpha) have been in oted in sin us mucosa ofpatients with chronic sinusitis. Respiratory ciliated cells have a functional reserve that allows them to autoregulate their ciliary beat in response to the changesin viscosity, modify in g intraacellular calcium levels [Ca+²]ic. Aim: Our goal was to determinate if TNFalpha affect this autoregulation to viscosity and calcium homeostasis. Material and Method: Primary cultures from adenoid tissue expiants. Ciliary beat frequency (CBF) was recorded usin g microphotodensitometry Cultures viere treated with TNF alpha (10 ng/ml) or control during 24 and 48 hours. Viscosity was increased by add in g dextran 500 10 percent and 20 percent. [Ca+²]ic was determined in cells loaded with Fura-2AM. Results: 48 hours treatment with TNFalpha produced a significant decrease in CBF at low viscosity significant increase in [Ca+²]ic and greater decrese in CBF in cultures treated with thapsigargin (endoplasmic calcium-ATPase pump blocker). Conclusions: After 48 hours of exposure to TNF alpha a negative effect in the adaptation mechanism to a low viscous media is observed in ciliated cells, probably secondary to changesin homeostasis of [Ca+²]ic.