A research group at Niigata University has shown that hinokitiol, a plant component, can treat pneumonia caused by Streptococcus pneumoniae (including resistant bacteria) using a mouse model.
Even excluding the new coronavirus infection, pneumonia is the third leading cause of death in Japan, with more than 3 domestic deaths from pneumonia each year.One of the reasons is that drug-resistant Streptococcus pneumoniae is increasing year by year due to frequent use of antibiotics.
In a previous study, this research group used hinokitiol, a component collected from plants such as "Atebi (Hiba Hinoki Asunaro)", which is a tree in Sado City, Niigata Prefecture, to kill Streptococcus pneumoniae including drug-resistant bacteria in vitro. I reported that.This time, it was verified whether hinokitiol can kill Streptococcus pneumoniae and whether it has a therapeutic effect on pneumonia in a biological pneumonia model using mice.
First, hinokitiol was administered to mice infected with Streptococcus pneumoniae, and the bactericidal action in vivo was investigated.As a result, Streptococcus pneumoniae (including resistant bacteria) in mouse alveoli was reduced by about 80% by administration of hinokitiol, demonstrating a bactericidal action by hinokitiol.
Subsequently, we observed the distribution of the enzyme elastase, which leaks from immune cells during infection with Streptococcus pneumoniae and damages self-tissues, and measured the concentration of cytokines that induce inflammation.As a result, in mice treated with hinokitiol, suppression of extracellular leakage of elastase was observed, and it was quantified that the activity of leaked elastase was reduced by about 90%.In addition, the production of inflammatory cytokines associated with Streptococcus pneumoniae infection was appropriately suppressed.That is, it was suggested that hinokitiol has an effect of suppressing damage to lung tissue and excessive inflammation.
From the above, it was clarified that hinokitiol kills Streptococcus pneumoniae including resistant bacteria even in the living body and exerts a therapeutic effect on pneumonia.This result is expected to be applied to a wide range of treatments for pneumonia including new coronavirus infections.
Paper information:[PLOS ONE] Treatment of severe pneumonia by hinokitiol in a murine antibiotic-resistant pneumococcal pneumonia model
