Down-regulation of miR-21-5p by pirfenidone to inhibit fibroblast proliferation in the treatment of acquired tracheal stenosis.

OBJECTIVE: Treatment options for acquired tracheal stenosis (ATS) are limited due to a series of pathophysiological changes including inflammation and cell proliferation. Micro ribonucleic acid-21-5p (miR-21-5p) may promote the excessive proliferation of fibroblasts. However, various types of fibrosis can be prevented with pirfenidone (PFD). Currently, the effect of PFD on miR-21-5p and its biological function has not been clarified. In this study, PFD was evaluated as a potential treatment for ATS by inducing fibroblast proliferation in lipopolysaccharide (LPS)-induced fibroblasts by targeting miR-21-5p. METHODS: For 48 h, 1 g/ml LPS was used to generate fibroblasts in vitro, followed by the separation of cells into four groups: control, PFD, mimic, and mimic + PFD. The Cell Counting Kit-8 (CCK-8) technique was adopted to measure the proliferation of fibroblasts. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB) were used to measure the relative expressions of tumor necrosis factor-α (TNF-α), transforming growth factor-ß1 (TGF-ß1), drosophila mothers against decapentaplegic 7 (Smad7) and collagen type I alpha 1(COL1A1) messenger RNA (mRNA) and proteins, respectively. RESULTS: (1) At 0, 24, 48, and 72 h, fibroblast growth was assessed using the CCK-8 method. Compared with the control group, the mimic group showed the highest fibroblast viability, and the PFD group showed the lowest fibroblast viability. However, fibroblast viability increased in the mimic + PFD group but decreased in the mimic one. (2) RT-qPCR and WB showed that the mimic group exhibited a significant up-regulation in the relative expressions of TNF-α, TGF-ß1, and COL1A1 mRNA and proteins but a down-regulation in the relative expression of Smad7 mRNA and protein compared with the control one. In the PFD group, the results were the opposite. Nevertheless, the relative expressions of TNF-α, TGF-ß1, and COL1A1 mRNA and proteins were increased, whereas that of Smad7 mRNA was decreased in the mimic + PFD group. The change was less in the mimic group. CONCLUSION: PFD may have a preventive and curative effect on ATS by inhibiting fibroblast proliferation and the fibrotic process and possibly through down-regulating miR-21-5p and up-regulating Smad7 and its mediated fibrotic and inflammatory responses.

Acquired tracheal stenosis: Cervical slide tracheoplasty.

Acquired tracheal stenosis can result from iatrogenic injury or, less commonly, tracheal tumors. Symptoms can arise insidiously and typically include respiratory distress, sleep disordered breathing, or exercise intolerance. Diagnostic evaluation includes cross-sectional imaging and endoscopy. Various endoscopic and open procedures exist to address acquired tracheal stenosis and treatment should be tailored to the patient. Cervical slide tracheoplasty without cardiopulmonary bypass is a versatile technique that can address different types of tracheal stenosis. It allows for immediate reconstruction with vascularized tissue and continued opportunity for growth as the child ages, with high success rates with minimal morbidity.

Tratamiento quirúrgico de la estenosis traqueal adquirida en pediatría / Surgical treatment of acquired tracheal stenosis in pediatrics

La estenosis traqueal adquirida es muy poco frecuente en la edad pediátrica y puede responder a múltiples causas; la estenosis posintubación y la secundaria a traqueotomía son las más comunes.El manejo de la estenosis traqueal adquirida sigue siendo controvertido. El tratamiento endoscópico proporciona el alivio inmediato de los síntomas, pero se asocia a una alta tasa de recurrencia, y el uso de prótesis endoluminales puede incrementar la longitud de la estenosis y complicar una cirugía futura. Por el contrario, se han documentado buenos resultados a largo plazo con la resección traqueal con anastomosis primaria.Se describe nuestra experiencia con la resección traqueal con anastomosis término-terminal para el tratamiento de la estenosis traqueal posintubación en 8 pacientes.

Acquired tracheal stenosis is a very infrequent lesion in the pediatric age group and may be due to diverse causes, being post-intubation stenosis and stenosis secondary to tracheostomy the most common ones.The management of acquired tracheal stenosis remains controversial. Endoscopic treatment provides immediate relief of symptoms but it is associated with a high recurrence rate, and the use of endoluminal prostheses can increase the length of the stricture complicating future surgery. Conversely, good long-term results have been documented with tracheal resection and primary anastomosis.We describe our experience with tracheal resection followed by end-to-end anastomosis for the treatment of post-intubation tracheal stenosis in 8 patients.

[Surgical treatment of acquired tracheal stenosis in pediatrics]. / Tratamiento quirúrgico de la estenosis traqueal adquirida en pediatría.

Acquired tracheal stenosis is a very infrequent lesion in the pediatric age group and may be due to diverse causes, being post-intubation stenosis and stenosis secondary to tracheostomy the most common ones. The management of acquired tracheal stenosis remains controversial. Endoscopic treatment provides immediate relief of symptoms but it is associated with a high recurrence rate, and the use of endoluminal prostheses can increase the length of the stricture complicating future surgery. Conversely, good long-term results have been documented with tracheal resection and primary anastomosis. We describe our experience with tracheal resection followed by end-to-end anastomosis for the treatment of post-intubation tracheal stenosis in 8 patients.

La estenosis traqueal adquirida es muy poco frecuente en la edad pediátrica y puede responder a múltiples causas; la estenosis posintubación y la secundaria a traqueotomía son las más comunes. El manejo de la estenosis traqueal adquirida sigue siendo controvertido. El tratamiento endoscópico proporciona el alivio inmediato de los síntomas, pero se asocia a una alta tasa de recurrencia, y el uso de prótesis endoluminales puede incrementar la longitud de la estenosis y complicar una cirugía futura. Por el contrario, se han documentado buenos resultados a largo plazo con la resección traqueal con anastomosis primaria. Se describe nuestra experiencia con la resección traqueal con anastomosis término-terminal para el tratamiento de la estenosis traqueal posintubación en 8 pacientes.

[Long-term results of the early endoscopic treatment of acquired tracheal-subglottic stenosis: 10 years of experience]. / Resultados a largo plazo del tratamiento endoscópico precoz de las estenosis subglóticas y traqueales adquiridas: 10 años de experiencia.

INTRODUCTION: Acquired stenosis of the airway is a common complication after endotracheal intubation. Endoscopic dilation has been accepted as the treatment of choice in cases detected precociously. Our goal is to know the current status of the patients treated in our hospital with endoscopic dilation in the last 10 years. MATERIAL AND METHODS: Retrospective cohort study of patients with subglottic and tracheal acquired stenosis (STAS) early treated endoscopically with balloon dilation at our center in the last 10 years. Bronchoscopy control at 2 weeks, a month, 3 and 6 months post-dilation were performed and later on depending on the symptoms. RESULTS: 32 patient were treated in the period considered. The median age was 4.5 (3-120) months. There were necessary 2.5 (1-5) dilations per patient. All cases were extubated in the operating room or in the following 24 hours. There were no complications during the procedure. Follow-up time was 6 (1-10) years. Only 1 of the 32 patients have had recurrence of stenosis 2 years after, it was secondary to reintubations due to new surgical interventions; which it was dilated successfully. CONCLUSIONS: Early endoscopic dilation in the acquired airway stenosis is a safe and effective long-term procedure. The results support the use of this technique as a treatment of choice in these patients.

INTRODUCCION: La estenosis adquirida de la vía aérea es una complicación frecuente tras la intubación endotraqueal. La dilatación endoscópica ha sido aceptada como tratamiento de elección en los casos detectados de forma precoz. Nuestro objetivo es conocer el estado actual de los pacientes tratados en nuestro centro mediante dilatación endoscópica en los últimos 10 años. MATERIAL Y METODOS: Estudio de cohorte retrospectivo de pacientes con estenosis subglóticas y traqueales adquiridas (ESTA) tratadas endoscópicamente mediante dilatación con balón en nuestro centro en los últimos 10 años. Se realizaron broncoscopias de control a las 2 semanas, al mes, a los 3 y 6 meses postdilatación y posteriormente en función de la clínica. RESULTADOS: Se trataron 32 pacientes de ESTA de reciente aparición en dicho periodo. La mediana de edad fue de 4,5 (3-120) meses. Fueron necesarias 2,5 (1-5) dilataciones por paciente. Todos los pacientes fueron extubados en quirófano o en las 24 horas siguientes al procedimiento. No hubo complicaciones durante los procedimientos ni durante el postoperatorio. El tiempo de seguimiento fue de 6 (1-10) años. Solo 1 de los 32 pacientes presentó recidiva de la estenosis 2 años después que fue secundaria a reintubaciones por nuevas intervenciones quirúrgicas; la cual se dilató nuevamente. CONCLUSIONES: La dilatación endoscópica precoz en las estenosis adquiridas de la vía aérea es un procedimiento seguro y eficaz a largo plazo. Los resultados avalan el uso de esta técnica como tratamiento de elección en estos pacientes.