The picture shows large lumps of E. coli (in red) that infects the bladder of a mouse with diabetes. Photo: Soumitra Mohanty |
Reduced immune systems and recurrent infections are common in type 1 and type 2 diabetes. Now researchers at Karolinska Institutet show that people with diabetes have lower levels of the antimicrobial peptide psoriasis, which is part of the body's immune system, which impacts the leaves' cell barrier with increased risk of urinary tract infection. The study is published in Nature Communications.
Diabetes is due to insulin deficiency or reduced insulin sensitivity. The hormone insulin regulates glucose (sugar) and thus energy to the body's cells. In people with type 1 diabetes, the body has stopped making insulin and in type 2 diabetes, cells have become less sensitive to insulin, which contributes to high blood glucose levels. Diabetes is a common disease that affects health in several ways.
Among other things, the innate immune system determinants and many get recurrent infections, such as urinary tract infections caused by E. colibacteria. In people with diabetes, there is an increased risk that these will lead to general blood poisoning, sepsis, which is based on the urinary tract.
A body-sealed antibiotic
Researchers at Karolinska Institutet have now investigated the relationship between psoriatic disease, a body-specific antibiotic that is part of the innate immune system, and blood glucose levels in people with diabetes (type 1, type 2 or prediabetes).
In urine, leaf cells and blood (serum) from patients, the researchers analyzed psoriasis and other peptides that are important for keeping the mucous membrane of the leaf intact and protecting against infection. The findings were then verified in mice and leaf cells with and without infection.
We found that high glucose levels lower the levels of antimicrobial peptide psoriasis, however, insulin has no effect. The lower levels of psoriasis that we see in diabetic patients, among other things, result in impaired function of the cells that normally protect the bladder from bacterial attacks, which increases the risk of infection in the bladder, says Annelie Brauner, professor at Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, who led the study.
Estrogen treatment reduced the amount of bacteria
Annelie Brauner's research team has previously been able to show that estrogen treatment restores the protective function of the leaf cells in humans and mice and thus can help regulate the immune response in urinary tract infection. The researchers therefore tested how estrogen therapy affects infected cells exposed to high glucose levels and were then able to show that treatment increased psoriatic levels and adjusted bacterial levels, indicating that estrogen can also have an effect in patients with diabetes.
Most recently, we plan to further the study of underlying mechanisms for infections in individuals with diabetes. The long-term goal is to reduce the risk of infection in this large and growing patient group, says the study's first author Soumitra Mohanty, who is a researcher at the same institution.
The study was conducted in collaboration with Karolinska University Hospital, Region Stockholm and Capio as well as Uppsala University and the University Clinic Schleswig-Holstein (Germany). It was mainly funded by the Olle Engkvist Builders Foundation, Stockholm Region (ALF funds), KI Research Foundation, Swedish Medical Association, Swedish Society for Medical Research (SSMF), the Clas Groschinsky Memorial Fund, Åke Wiberg Foundation and the Magnus Bergvalls Foundation. There are no reported conflicts of interest.
Source/Credit: Karolinska Institutet | Felicia Lindberg
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