Recombinant human thrombomodulin attenuated sepsis severity in a non-surgical preterm mouse model

Abstract

neonatal sepsis is characterised by dysregulated immune responses. Lipid mediators (LMs) are involved in the regulation of inflammation. Human recombinant thrombomodulin (rhTM), an anticoagulant, has anti-inflammatory effects and might be useful for sepsis treatment. A stock caecal slurry (CS) solution was prepared from adult caeca. To induce sepsis, 1.5 mg/g of CS was administered intraperitoneally to 4 d-old wild-type FVB mouse pups. Saline (Veh-CS) or rhTM (3 or 10 mg/kg; rhTM3-CS or rhTM10-CS) was administered subcutaneously 6 h prior to sepsis induction, and liver LM profiles at 3 and 6 h postsepsis induction and survival up to 7 days were examined. Mortality was significantly lower (47%) in the rhTM3-CS group and significantly higher (100%) in the rhTM10-CS group, compared with the Veh-CS group (79%, p < 0.05). Eleven LMs (12-HEPE, EPA, 14-HDHA, DHA, PD1, PGD 2 , 15d-PGJ 2 , 12S-HHT, lipoxin B 4 , 12-HETE, AA) were significantly increased at 3 h, and five LMs (5-HEPE, 15-HEPE, 18-HEPE, 17-HDHA, PD1) were significantly increased at 6 h post-sepsis induction. Increased EPA, DHA, 12S-HHT, lipoxin B 4 , and AA were significantly suppressed by rhTM pre-treatment. rhTM was protective against neonatal sepsis. This protective effect might be mediated via LM modulation. Further post-sepsis studies are needed to determine clinical plausibility.

Protective Role of an Initial Low-Dose Septic Challenge against Lethal Sepsis in Neonatal Mice: A Pilot Study

“…At least three different litters were used for survival experiments to eliminate any litter bias effects. For identification, the back or tail of each pup was labeled using a Sharpie marker as described previously [22]. This study was carried out in accordance with the ARRIVE guidelines and performed as approved by the Kobe University Institutional Animal Care and Use Committee (Protocol P180505).…”

“…As described previously [21][22][23], a single stock CS solution was prepared from adult ceca and then stored at −80 • C in 1 mL aliquots until use. For examining bacterial viability, an aliquot of stock CS was thawed at room temperature, and 50 µL was plated onto 1.5% agar containing brain/heart infusion (BHI) broth [23].…”

“…To induce sepsis, seven-day-old mouse pups that are immunologically equivalent to human term infants [24], were given various doses of CS intraperitoneally (IP) and then closely monitored daily for health and survival up to seven days, based on the method used in our previous studies [21,22]. Similar to that in a previous report, clear dose-dependent increase in mortality (0% for 0.5 mg/kg bodyweight (BW), 61% for 1.0 mg/kg BW, 83% for 1.5 mg/kg BW, and 100% for 2.0 mg/kg BW, n ≥ 10 in each group (Figure 1) was found [21,22]. For subsequent studies, a CS of 0.5 and 1.5 mg/kg BW were used for the initial low-dose septic challenge (non-lethal) and lethal septic induction, respectively.…”

“…Samples underwent solid-phase extraction on C18 columns and were subjected to LC-MS/MS. The levels of targeted LMs were quantified by a multiple reaction monitoring method, and the LMs were identified using published criteria [22,27].…”

Protective Effects of Ulinastatin Combined With Thrombomodulin Against Lipopolysaccharide Induced Liver and Kidney Injury in Septic Rats

“…In previous studies, both UTI and TM have been found to have therapeutic effects on sepsis (Jiang et al 2018;Wu et al 2019;Wang et al 2019;Ashina et al 2020), and more meaningfully, a number of studies have shown that UTI combined with other drugs can effectively improve the treatment effect of sepsis (Meng et al 2020;Wang et al 2020). At present, there are many research projects on sepsis, but the research based on drug combination therapy is not su cient.…”