Instability of microsatellites linked to targeted genes inCRISPR/Cas9-edited and traditional gene knockout mouse strains

The classic method for gene knockout (KO) is based on homologous recombination (HR) and embryonic stem cell technique (Gerlai,1996).Actually,the procedure of homologous replacement is complicated and time consuming,although it has been popular during the past decades.Recent years,genome editing which can cause DNA sequence-specific mutations in the genomes of cellular

SOCS3 Expression Correlates with Severity of Inflammation in Mouse Hepatitis Virus Strain 3-induced Acute Liver Failure and HBV-ACLF

Summary： Recently, suppressor of cytokine signaling-3 （SOCS3） has been shown to be an inducible endogenous negative regulator of Janus kinase/signal transducers and activators of transcription （JAK/STAT） pathway which is relevant in inflammatory response, while its functions in acute liver failure and HBV-induced acute-on-chronic liver failure （HBV-ACLF） have not been fully elucidated. In this study, we explored the role of SOCS3 in the development of mouse hepatitis virus strain 3 （MHV-3）-induced acute liver failure and its expression in liver and peripheral blood mononuclear cells （PBMCs） of patients with HBV-ACLF. Inflammation-related gene expression was detected by real-time PCR, immtmohistochemistry and Western blotting. The correlation between SOCS3 level and liver injury was studied. Our results showed that the SOCS3 expression was significantly elevated in both the liver tissue and PBMCs from patients with HBV-ACLF compared to mild chronic hepatitis B （CHB）. Moreover, a time course study showed that SOCS3 level was increased remarkably in the liver of BALB/cJ mice at 72 h post-infection. Pro-inflammatory cytokines, interleukin （IL）-1 β, IL-6, and tumor necrosis factor （TNF）-α, were also increased significantly at 72 h post-infection. There was a close correlation between hepatic SOCS3 level and IL-6, and the severity of liver injury defined by alanine aminotransferase （ALT） and aspartate aminotransferase （AST） levels, respectively. These data suggested that SOCS3 may play a pivotal role in the pathogenesis of MHV-3-induced acute liver failure and HBV-ACLF.

Collection of superovulated mouse oocytes continuously by surgery and their development after activation

Objective:To establish a new way to collect superovulated oocytes or zygotes repeatedlyfrom an individual mouse.Methods:Superovulations were induced by injection PMSG and hCG in Kunming strainmice.The ampullaes of oviduct of all anaesthetised mouse were put in a specially designed'U'sink and released.The second and third times of PMSG injection were made on the sixth day andeleventh day after the first superovulation injection.The capacity of development was examinedby in vitro culture of parthenogenesis activation oocytes.Results:Development to blastocyst stage was not significantly different between the first andsecond time collection.The percentage of blastocyst stage in CD and Sr^(++) treatment was signifi-cantly higher(P<0.05)than the oocytes treated in CB and Sr^(++).Conclusion:This method enables us to collect oocytes or zygotes repeatedly from one individ-ual mouse in an interval as short as 5 days and without influence on the quality of oocytes.

Effects of LW-AFC,a new formula derived from Liuwei Dihuang decoction,on intestinal microbiome in senescence-accelerated mouse prone 8 strain,a mouse model of Alzheimer disease

OBJECTIVE To investigate the effects of LW-AFC,a new formula derived fromLiuwei Dihuang decoction,on gut microbiota and the behavior of learning and memory of SAMP8 mice,a mouse model of Alzheimer Disease(AD),and identify the specific intestinal microbiota correlating with cognitive ability.METHODS Morris-water maze test,novel object recognition test and shuttle-box test were conducted to observe the ability of learning and memory.16S rRNA amplicon sequencing(Illumina,San Diego,CA,USA)was employed to investigate gut microbiota.RESULTS The treatment of LW-AFC improved cognitive impairments of SAMP8 mice,including spatial learning and memory ability,active avoidance response,and object recognition memory capability.Our data indicated that there were significantly 8 increased and 12 decreased operational taxonomic units(OTUs)in the gut microbiota of SAMP8 mice compared with senescence accelerated mouse resistant 1(SAMR1) strains,the control of SAMP8 mice.The treatment of LW-AFC altered 22(16 increased and 6 decreased)OTUs in SAMP8 mice and among them,15 OTUs could be reversed by LW-AFC treatment resulting in a microbial composition similar to that of SAMR1 mice.We further showed that there were7(3 negative and 4 positive correlation)OTUs significantly correlated with all the three types of cognitive abilities,at the order level,including Bacteroidales,Clostridiales,Desulfovibrionales,CW040,and two unclassified orders.LW-AFC had influences on bacterial taxa correlated with the abilities of learning and memory in SAMP8 mice and restored them to SAMR1 mice.CONCLUSION The effects of LW-AFC on improving cognitive impairments of SAMP8 mice might be via modulating intestinal microbiome and LW-AFC could be used as a potential anti-AD agent.

Strain-and sex-specific differences in intestinal microhemodynamics and gut microbiota composition

Background:Intestinal microcirculation is a critical interface for nutrient exchange and energy transfer,and is essential for maintaining physiological integrity.Our study aimed to elucidate the relationships among intestinal microhemodynamics,genetic background,sex,and microbial composition.Methods:To dissect the microhemodynamic landscape of the BALB/c,C57BL/6J,and KM mouse strains,laser Doppler flowmetry paired with wavelet transform analysis was utilized to determine the amplitude of characteristic oscillatory patterns.Microbial consortia were profiled using 16S rRNA gene sequencing.To augment our investigation,a broad-spectrum antibiotic regimen was administered to these strains to evaluate the impact of gut microbiota depletion on intestinal microhemodynamics.Immunohistochemical analyses were used to quantify platelet endothelial cell adhesion molecule-1(PECAM-1),estrogen receptorα(ESR1),and estrogen receptorβ(ESR2)expression.Results:Our findings revealed strain-dependent and sex-related disparities in microhemodynamic profiles and characteristic oscillatory behaviors.Significant differences in the gut microbiota contingent upon sex and genetic lineage were observed,with correlational analy-ses indicating an influence of the microbiota on microhemodynamic parameters.Following antibiotic treatment,distinct changes in blood perfusion levels and velocities were observed,including a reduction in female C57BL/6J mice and a general decrease in perfusion velocity.Enhanced erythrocyte aggregation and modulated endothelial function post-antibiotic treatment indicated that a systemic response to microbiota depletion impacted cardiac amplitude.Immunohistochemical data revealed strain-specific and sex-specific PECAM-1 and ESR1 expression patterns that aligned with observed intestinal microhemodynamic changes.Conclusions:This study highlights the influence of both genetic and sex-specific factors on intestinal microhemodynamics and the gut microbiota in mice.These findings also emphasize a substantial correlation between intestinal microhemodynamics and the compositional dynamics of the gut bacterial community.