Carrimycin ameliorates lipopolysaccharide and cecal ligation and puncture-induced sepsis in mice

Carrimycin(CA),sanctioned by China’s National Medical Products Administration(NMPA)in 2019 for treating acute bronchitis and sinusitis,has recently been observed to exhibit multifaceted biological activities,encompassing anti-inflammatory,antiviral,and anti-tumor properties.Despite these applications,its efficacy in sepsis treatment remains unexplored.This study introduces a novel function of CA,demonstrating its capacity to mitigate sepsis induced by lipopolysaccharide(LPS)and cecal ligation and puncture(CLP)in mice models.Our research employed in vitro assays,real-time quantitative polymerase chain reaction(RT-qPCR),and RNA-seq analysis to establish that CA significantly reduces the levels of pro-inflammatory cytokines,namely tumor necrosis factor-alpha(TNF-α),interleukin 1 beta(IL-1β),and interleukin 6(IL-6),in response to LPS stimulation.Additionally,Western blotting and immunofluorescence assays revealed that CA impedes Nuclear Factor Kappa B(NF-κB)activation in LPS-stimulated RAW264.7 cells.Complementing these findings,in vivo experiments demonstrated that CA effectively alleviates LPS-and CLP-triggered organ inflammation in C57BL/6 mice.Further insights were gained through 16S sequencing,highlighting CA’s pivotal role in enhancing gut microbiota diversity and modulating metabolic pathways,particularly by augmenting the production of short-chain fatty acids in mice subjected to CLP.Notably,a comparative analysis revealed that CA’s anti-inflammatory efficacy surpasses that of equivalent doses of aspirin(ASP)and TIENAM.Collectively,these findings suggest that CA exhibits significant therapeutic potential in sepsis treatment.This discovery provides a foundational theoretical basis for the clinical application of CA in sepsis management.

Accelerated Autophagy of Cecal Ligation and Puncture-Induced Myocardial Dysfunction and Its Correlation with Mammalian Target of Rapamycin Pathway in Rats

Background：Recent studies have indicated that autophagy is involved in sepsis-induced myocardial dysfunction.This study aimed to investigate the change of autophagy in cecal ligation and puncture （CLP）-induced myocardium dysfunction and its relationship with mammalian target of rapamycin （mTOR） pathway.Methods：Totally,12 rats were randomly divided into CLP group or sham-operated （SHAM） group.Cardiac tissues were harvested 18 h after CLP or sham operation.Pathology was detected by hematoxylin and eosin staining,cardiac functions by echocardiography,distribution ofmicrotubule-associated protein light chain 3 type Ⅱ （LC3II） by immunohistochemical staining,and autophagic vacuoles by transmission electron microscopy.Moreover,phosphorylation of mTOR （p-mTOR）,phosphorylation of S6 kinase-1 （PS6K1）,and LC3II and p62 expression were measured by western blotting.Pearson＇s correlation coefficient was used to analyze the correlation of two parameters.Results：The results by pathology and echocardiography revealed that there was obvious myocardial injury in CLP rats （left ventricle ejection fraction：SHAM 0.76 ± 0.06 vs.CLP 0.59 ± 0.l l,P 〈 0.01;fractional shortening：SHAM 0.51 ± 0.09 vs.CLP 0.37 ± 0.06,P 〈 0.05）.We also found that the autophagy process was elevated by CLE the ratio of LC3II/LC3I was increased （P 〈 0.05） while the expression of p62 was decreased （P 〈 0.05） in the CLP rats,and there were also more autophagosomes and autolysosomes in the CLP rats.Furthermore,the mTOR pathway in CLP myocardium was inhibited when compared with the sham-operated rats;p-mTOR （P 〈 0.01） and PS6K 1 （P 〈 0.05） were both significantly suppressed following CLP challenge.Interestingly,we found that the mTOR pathway was closely correlated with the autophagy processes.In our study,while p-mTOR in the myocardium was significantly correlated with p62 （r=0.66,P =0.02）,PS6K1 was significantly positively correlated with p62 （r =0.70,P =0.01） and negatively correlated with LC31I （r =-0.71,P =0.01）.Conclusions：The autophagy process in the myocardium was accelerated in CLP rats,which was closely correlated with the inhibition of the mTOR pathway.

Astragaloside IV Attenuates Polymicrobial Sepsis-Induced Cardiac Dysfunction in Rats via IKK/NF-κB Pathway

Objective To evaluate the protective effects of Astragaloside IV(AST)in a rat model of myocardial injury induced by cecal ligation and puncture(CLP).Methods The model of sepsis-induced cardiac dysfunction was induced by CLP.Using a random number table,50 specific pathogen free grade of Sprague Dawley rats were randomized into 5 groups:the sham group(sham),the model group(CLP,18 h/72 h)and AST group(18 h/72 h).Except the sham group,the rats in other groups received CLP surgery to induce sepsis.CLP groups received intragastric administration with normal saline after CLP.AST groups received intragastric administration with AST solution(40 mg/kg)once a day.The levels of inflammatory mediators and oxidative stress markers in the serum of the septic rats were determined via enzyme-linked immunosorbent assay(ELISA)at different time point,such as interleukin 6(IL-6),IL-10,high mobility group box-1 protein B1(HMGB-1),superoxide dismutase(SOD),and malondialdehyde(MDA).Cardiac function was determined by echocardiography.Moreover,changes in myocardial pathology were evaluated using hematoxylin and eosin staining.The levels of lactate dehydrogenase(LDH)and creatine kinase-MB(CK-MB)were analysed to determine the status of CLP-induced myocardium.In addition,the apotosis of myocardial cells was analysed by terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL).The protein levels of B-cell lymphoma-2(Bcl-2),Bcl-2-associated X(Bax),IκB kinaseα(IKKα),nuclear factor kappa B p65(NF-κB p65)were detected by Western blot analysis.Moreover,survival rate was investigated.Results AST improved the survival rate of CLP-induced rats by up to 33.3%(P<0.05).The cardioprotective effect of AST was observed by increased ejection fraction,fractional shortening and left ventricular internal diameter in diastole respectively(P<0.01 or P<0.05).Subsequently,AST attenuated CLP-induced myocardial apoptosis and the ratio of Bcl-2/Bax in the myocardium,as well as the histological alterations of myocardium(P<0.01 or P<0.05);the generation of inflammatory cytokines(IL-6,IL-10,HMGB-1)and oxidative stress markers(SOD,MDA)in the serum was significantly alleviated(P<0.01 or P<0.05).On the other hand,AST markedly suppressed CLP-induced accumulation of IKK-αand NF-κB p65 subunit phosphorylation(P<0.01 or P<0.05).Conclusions AST plays a significant protective role in sepsis-induced cardiac dysfunction and survival outcome.The possible mechanism of cardioprotection is dependent on the activation of the IKK/NF-κB pathway in cardiomyocytes.