Conclusion
Neonatal E. coli sepsis leads to increased expression of renal tissue inflammation and injury biomarkers consistent with AKI, which may be attenuated with PTX combined with antibiotic treatment.
Methods
Postnatal (PN) day 1 C57BL/6J mice were injected with E. coli K1 strain at 105 colony forming units per gram weight or saline control. After 1.5 hours, septic pups randomly received saline, gentamicin or cefotaxime, with/without PTX. 5.5h after sepsis initiation, kidneys and blood were harvested for measurements of biomarkers of inflammation and kidney injury. Renal sections from PN7 mice were used for histology and immunofluorescence. Linear mixed effect models were employed to fit the outcomes including interaction between treatment group and sex.
Results
Septic mice demonstrated robust expression of pro-inflammatory cytokines, chemokines and biomarkers of tubular injury in renal tissue, which were attenuated in response to combined PTX and antibiotics (gentamicin or cefotaxime): chemokines (p<0.001), plasma (p<0.01) and tissue IL-6 (p<0.05), plasma TNF (p<0.001), NGAL (p<0.01), CXCL10 (p<0.01), osteopontin (p<0.05), and VEGF (p<0.05), with a trend for KIM-1 (tissue concentration: p=0.21, fluorescence area: p=0.12). Interactions between treatment and sex were present for several cytokines and kidney injury biomarkers. Immunofluorescence findings for the tubular injury markers (NGAL and KIM-1) were consistent with biomarker expression in tissue lysates.