Application of Perfluorooctylbromide Nanoparticles with Ulinastatin for Early Brain Injury Caused by Carbon Monoxide Poisoning

ABSTRACTThis study aimed to explore the mechanism of perfluorooctylbromide (PFOB) nanoparticles (NPs) combined with ulinastatin (UTI) on early brain injury (EBI) caused by carbon monoxide poisoning (CMP). Firstly, PFOB NPs were prepared by high-speed dispersion and high-speed homogenization. The physicochemical characteristics of the particle size distribution and Zeta potential distribution of the NPs were analyzed using a laser particle size analyzer. The thermal and photoinduced phase transition characteristics of the NPs were analyzed under heating and laser irradiation conditions. Then, 50 Sprague Dawley (SD) rats were deemed as the research objects to establish the CMP rat models using hyperbaric oxygen chambers. According to different treatment methods, they were rolled into a healthy control group, a carbon monoxide (CO) model group, a PTOB treatment group, an UTI treatment group, and a PTOB + UTI treatment group. The brain tissues of each group of rats were collected 3 days after treatment. The neuronal cell apoptosis, expression of Caspase-3, messenger ribonucleic acid (mRNA) of inflammatory factors interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in rat brain tissue were detected through immunohistochemical staining, in situ cell apoptosis detection, Reverse transcription-polymerase chain reaction (RT-PCR), and Western blotting, so did the relative expression of target proteins B-cell lymphoma-2 (Bcl-2), Bcl2-Associated X (Bax) and myelin basic protein (MBP). As a result, the average particle size and the average Zeta potential of the prepared PFOB NPs was 103±31 nm and −23 ± 15 mV, respectively. When the PFOB NPs were heated to 80 °C, the particle size increased greatly and cracks appeared. The particle size of PFOB NPs also increased obviously after laser irradiation, and the PFOB inside the particles changed into gas phase. Compared to CO group, expression of Caspase-3, neuronal cell apoptosis rate, mRNA expression of IL-1β and TNF-α, and protein expression of Bax and Bcl-2 in the brain tissue of PTOB group, UTI group, and PFOB + UTI group were notably decreased (P < 0.05), while the MBP protein expression increased considerably (P < 0.05). Changes in PFOB + UTI group were more obvious than those in PTOB group and UTI group, and those indicators weren’t considerably different from the controls. In summary, PFOB NPs were successfully prepared with favorable phase transition characteristics. Moreover, PFOB NPs combined with UTI could reduce the apoptosis of brain neurons after CMP, improve the inflammatory response, and play a protective effect on EBI of CMP.