Effect of Treatment with Pyridostigmine on the Levels of IL‐10, IFN‐α and IL‐1β in the Bronchoalveolar Lavage (BAL) Supernatant in an Experimental Model of Acute Respiratory Distress Syndrome (ARDS) in Mice
Authors: Lira Beatriz Oliveira Mauricio , de Morais Tercio Lemos , Cavini Yolanda Gomes , Borges Vitor Barbosa , Choque Pamela , de Oliveira Ana Paula Ligeiro , Colombo Fernanda 
Published: June 2021

IntroductionAcute Respiratory Distress Syndrome (ARDS) is a severe clinical syndrome, with a high mortality rate. Its main milestone is the change in alveolar‐capillary permeability, culminating in pulmonary epithelial injury. The mechanism of injury of ARDS involves immune events, activated by various inflammatory cytokines, including IL‐1, INF‐α, which counteract the production of anti‐inflammatory cytokines, such as IL‐10. The extent of the lesion depends on the balance between the pro‐inflammatory and anti‐inflammatory responses. Recently, the role of the autonomic nervous system in the modulation of the immune response has been demonstrated. The concept of “cholinergic anti‐inflammatory reflex” has been studied as a new treatment in different models of septic and aseptic inflammation, due to its property in reducing the inflammatory response through the activation of the vagus nerve and, consequently, tissue damage. However, little is known about the relationship between “cholinergic anti‐inflammatory reflex” and acute lung injury.ObjectiveTo evaluate the effects of cholinergic pathway stimulation, by administration of anticholinesterase, pyridostigmine (PYR), on IL‐10, INF‐α and IL‐1β levels in the bronchoalveolar lavage supernatant (BAL) in an experimental model of ARDS.MethodsWe used C57BI/6 male mice that were divided into 4 experimental groups: control group (n = 4); LPS group (n = 12); LPS group treated with 1 dose of PYR per day (n = 6); and LPS group treated with 2 doses of PYR per day (n = 10). ARDS was induced by daily intratracheal administration of lipopolysaccharide (LPS) at a concentration of 10μg/ml + 0.9% saline solution which was applied with the aid of a 20μl micropipette and PYR was given daily by gavage, divided into two doses of 1.5mg/kg/day diluted in 150μl saline, the LPS + PYR 1 dose per day and LPS + PYR 2 doses per day, received the first dose after 1 hour of LPS administration, and after 12 hours of the first dose, the LPS + PYR 2 doses received the second dose, completing 3mg/kg/day which is the dose described in the literature to inhibited 85% of acetylcholinesterase activity. After 72 hours of follow‐up the animals were euthanized. After the euthanasia the BAL was collected, where it was possible to quantify the cytokines IFN‐α, IL‐1β and IL‐10 by the ELISA method. For statistical analysis we used the ANOVA test.ResultsAdministration of LPS induced increased IFN‐α and IL‐1βcytokine concentrations in lung tissue but did not modify IL‐10 levels. Mice treated with two daily doses of PYR for 72h had significantly lower levels of IFN‐α and IL‐1β when compared to the untreated groups and the group treated with only one daily dose as we can see in table 1 and graphics 1 and 2.ConclusionWe observed in this experimental model that administration of pyridostigmine, which increases cholinergic activity, decreased the production of proinflammatory cytokines in the lung in a mice ARDS model.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.