A Study Of 2-bromopalmitate-induced Inflammation Leading To Visceral And Testicular Dysfunction In Mice

Post-translational protein modification(PTM),such as acetylation,ubiquitination,methylation and fatty acylation modifications,can change the structure,chemical properties and functions of proteins,and are important regulatory mechanisms for cellular proteins.Proteins can be modified by fatty acylation by adding a variety of lipid groups,including different fatty acids.Most lipid modifications are irreversible,but the addition of 16 or 18 carbon atoms of saturated palmitic acid or stearate groups to the sulfhydryl group of cysteine(Cys)to form thioester bonds,that is,S-Palmitoylation,is a reversible modification that has an important regulatory effect on the localization,function,and physiological activity of the modified protein.2-bromopalmitate(2-BP)is a commonly used protein palmitation inhibitor to explore the palmitoylation modification status and role of some specific proteins.In this study,an experimental animal model was constructed by intraperitoneal injection of 2-BP into adult male mice,and the effects of different concentrations of 2-BP on visceral inflammation,intestinal microorganisms and male reproductive function of mice were explored by HE staining,IHC,RT-q PCR,GC,16 S r DNA sequencing,CASA and other technologies.The main results of this study are as follows:(1)Intraperitoneal injection of 50 mg/kg and 100 mg/kg 2-BP promoted spleen and kidney inflammation in mice.HE results showed that nucleus chromatin concentration in spleen tissues of 2-BP treated group increased spleen cell necrosis.Nebular tube wall vacuoleization and interstitial inflammatory cell infiltration.RT-q PCR showed that 2-BP caused an increase in the expression of pro-inflammatory factors IL-1a,TNF-a and IL-6 in the spleen and kidneys of mice.The livers of mice in the 50 mg/kg 2-BP group exhibited steteatosis on day 36,while 100 mg/kg 2-BP inhibited liver inflammation in mice.(2)The body weight of mice continued to decrease during intraperitoneal injection of100 mg/kg 2-BP,and returned to normal within a few days of discontinuation;Intestinal strictures and adhesions in mice in the 100 mg/kg 2-BP group on day 36.Compared with the Control group,the 2-BP treatment changed the structure of the intestinal flora of mice,and compared with the Control group,the phylum Firmicutes,Clostridiales,and RC9genera(Rikenellaceae＿RC9＿gut＿group)in the intestines of mice in the 2-BP group on day10 were significantly enriched.On day 36,50 mg/kg 2-BP group was significantly enriched in Desulfovibrio,and 100 mg/kg 2-BP group Muri and Alistipes were significantly enriched.(3)Intraperitoneal injection of 50 mg/kg and 100 mg/kg 2-BP both had the effect of inhibiting testicular inflammation on day 10,but significantly promoted the development of testicular inflammation on day 36.Intraperitoneal injection of 100 mg/kg 2-BP caused intratesticular spermatogenesis damage,dysbacteriogenesis of germ cell arrangement,and disappearance of the lumen of the spermatogenic tubule;The rate of sperm malformation in the tail of the epididymis of mice increased,and the number and motility were significantly reduced.This study shows that 2-BP may induce visceral and testicular inflammation by changing the structure of mouse gut microorganisms,causing dysfunction of internal organs and testicles.This study can provide a scientific basis for understanding the effects of high doses of 2-BP on mammals,and also provide important support for exploring the process of protein palmitation.