Browsing by Subject "short chain fatty acid"

Chlamydia pneumoniae is an intracellular Gram-negative bacterium, that can cause respiratory infections. Infections are typically mild or asymptomatic, but it can also lead to more severe infections, for example, pneumonia. Severe infections might need antibiotic treatment. When the bacteria are exposed to stressful conditions, they can change to a chronic, persistent form. Amoxicillin and penicillin are known to transform bacterium into persistent forms. Antibiotics are not effective for persistent infection very often. Amoxicillin is the recommended treatment for pneumonia in Finland and worldwide, which is problematic from the perspective of C. pneumoniae. That is why there is a need for effective treatment for persistent C. pneumoniae infection. Probiotics and their by-products short chain fatty acids (SCFAs) are known to have beneficial effects on human health. Based on the current knowledge, SCFAs and other probiotic by-products are known to inhibit pathogen bacterial growth. Thus, SCFAs could have a potential effect on the treatment of C. pneumoniae infection. The aim of this work is to study the impact of SCFAs, acetate, propionate, and butyrate on C. pneumoniae infection and its antibiotic susceptibility. To study the impact of acetate, propionate and butyrate on C. pneumoniae infection and its antibiotic susceptibility, three different infection models were used: productive C. pneumoniae infection model with A549 cells, amoxicillin-induced persistent infection model with A549 cells, and persistent infection model with THP1 cells. Bacterial growth was followed with immunofluorescence and the number of the bacterial genome was studied with quantitative polymerase chain reaction (qPCR). The studied SCFAs did not have a significant impact on productive C. pneumoniae infection. With amoxicillin- induced persistent infection, the results were varying. For example, sodium acetate, and propionate showed some increase in bacterial growth on the first infection, but with sodium butyrate, there were not any impact. The only SCFA that decreased the bacterial growth in the persistent infection model with THP1 cells was sodium butyrate (200 μM). The same treatment also decreased the number of bacterial genomes with qPCR in the same infection model. In addition, the same condition increased the antibiotic susceptibility of persistent C. pneumoniae to azithromycin in THP1 cells. In conclusion, the studied SCFAs seemed to have more impact on C. pneumoniae infection with human immune cells compared to human lung epithelial cells. Based on this study, sodium butyrate could have positive impacts against persistent C. pneumoniae infection. Nevertheless, further studies of the impact of sodium butyrate on persistent C. pneumoniae infection are needed.