Construction of the Pkd1 gene knockout mouse model with polycystic kidney disease based on CRISPR/Cas9 technology / 中华肾脏病杂志

Objective:To establish a conditional knockout mouse model of polycystic kidney disease 1 ( Pkd1) gene based on CRISPR/Cas9 and Cre-loxP gene editing technology, and to provide an animal model for in-depth research on the role of Pkd1 gene in the development of polycystic kidney disease. Methods:In-Fusion technology was used to construct a targeting vector. Corresponding gRNAs, Cas9 mRNAs, and donor vectors carrying the loxP site were prepared based on the Pkd1 gene, and injected into the fertilized eggs of C57BL/6N mice. The fertilized eggs were transferred to the fallopian tubes of female mice with pseudopregnancy. After the newborn mice were identified by PCR and sequencing analysis, Pkd1 flox/flox F0 generation positive mice were selected. The F0 generation positive mice were bred with wild-type mice, and F1 generation heterozygous mice with Pkd1 flox/+ genotype were selected for offspring. F2 generation homozygous mice with Pkd1 flox/flox genotype were obtained through internal expansion, and then hybridized with Cre positive Ggt1/ Cre mice. F3 generation mice with Pkd1 flox/+Ggt1 Cre genotype were obtained. F4 generation mice with Pkd1 flox/flox Ggt1 Cre genotype were obtained by self crossing or backcrossing with F2 generation Pkd1 flox/flox, namely kidney-specific Pkd1 gene knockout mice ( Ggt1-cKO mice). PCR method was used to identify the genotype of mice, and then the mice were divided into wild-type control (WT) group ( n=6), Pkd1 homozygous control (PKD) group ( n=6), and Ggt1-cKO knockout validation (CKO) group ( n=6) according to the gene identification results. Real-time fluorescence quantitative PCR (RT-qPCR) was used to detect the expression of Pkd1 mRNA in the kidneys and other organs of mice in each group. HE staining was used to detect the pathological changes in renal tissues of mice in each group. The automatic biochemical detector was used to detect the blood urea nitrogen and serum creatinine levels of mice, and the kidney coefficient was calculated. Results:The PCR detection results showed that the genotype of offspring mice in CKO group was consistent with Pkd1floxflox Ggt1 Cre. Pkd1 gene was only specifically expressed in the kidney, but not in other tissues. The RT-qPCR results showed that the relative expression of Pkd1 mRNA in the renal medulla of CKO group was significantly lower than that of WT and PKD groups. The kidney volume of the CKO group had increased by about twice compared to the WT group. Under the microscope, it could be observed that there were multiple vacuoles of varying sizes and shapes in the kidneys of the CKO group, and there was a significant increase in the interstitial space of the medullary tissue. The kidney coefficient, blood urea nitrogen, and serum creatinine in the CKO group were significantly higher than those in the WT and PKD groups (all P<0.05). Conclusion:Based on CRISPR/Cas9 and Cre-loxP gene editing technology, Pkd1 gene kidney conditional knockout mice can be successfully constructed, providing an animal model for further studying the action mechanism of Pkd1 gene in polycystic kidney disease.

Exploring the mechanism by which acupuncture and moxibustion reduce colonic mucosal inflammation in rats with ulcerative colitis(UC)based on the P2X7R-NLRP3 inflammasome pathway / 针灸推拿医学（英文版）

Objective:To explore the mechanism of acupuncture and moxibustion for ulcerative colitis(UC)from the perspective of the P2X7 receptor(P2X7R)-nucleotide-binding oligomerization domain(NOD)-like receptor protein 3(NLRP3)inflammasome pathway. Methods:Sprague-Dawley rats were randomly assigned to a normal(N)group,a model(M)group,a herb-partitioned moxibustion(HM)group,and an electroacupuncture(EA)group.For modeling,the rats drank 4%dextran sulfate sodium for 7 d.Rats in the HM group and EA group received 7 consecutive days of HM or EA at bilateral Tianshu(ST25),respectively.The histopathological change in colon tissue was observed by hematoxylin-eosin(HE)staining;immunofluorescence staining was used to detect the protein expression of related molecules in the colon tissue,and enzyme-linked immunosorbent assay was used to detect the concentrations or contents of related molecules in the serum and colon tissue.Wild-type(WT)and P2X7R gene knockout(KO)mice were used to construct UC models,histopathological changes in the colon tissue were observed by HE staining,and the NLRP3 protein expression in the colon tissue was observed by immunohistochemistry. Results:Compared with the N group,the colon histopathological score in the M group was significantly increased,and the protein expression of P2X7R,NLRP3,apoptosis-associated speck-like protein containing CARD(ASC),Caspase-1,interleukin-1β(IL-1β),and interleukin-18(IL-18)in the colon tissue and the protein levels of IL-1β and IL-18 in the serum were significantly increased(P<0.05).Compared with the M group,the histopathological scores of the colon in the HM group and the EA group were significantly decreased,and the protein expression levels of P2X7R,NLRP3,ASC,Caspase-1,IL-1β,and IL-18 in the colon tissue and the protein level of IL-18 in the serum were significantly decreased(P<0.05).After UC modeling,the colonic mucosal epithelial damage and inflammatory cell infiltration in P2X7R KO mice were less than those in WT mice,and the NLRP3 protein expression in the colon was also decreased compared with that in WT mice(P<0.05). Conclusion:HM and EA at Tianshu(ST25)may inhibit the protein activities of P2X7R,NLRP3,ASC,and Caspase-1 in the colon tissue of rats with UC,thereby reducing the downstream molecules IL-1β and IL-18 in the P2X7R-NLRP3 inflammasome pathway to relieve UC inflammation.

Effects of CACNA1H gene knockout on autistic-like behaviors and the morphology of hippocampal neurons in mice / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effects of CACNA1H gene knockout (KO) on autistic-like behaviors and the morphology of hippocampal neurons in mice.@*METHODS@#In the study, 25 CACNA1H KO mice of 3-4 weeks old and C57BL/6 background were recruited as the experimental group, and 26 wild type (WT) mice of the same age and background were recruited as the control group. Three-chamber test and open field test were used to observe the social interaction, anxiety, and repetitive behaviors in mice. After that, their brain weight and size were measured, and the number of hippocampal neurons were observed by Nissl staining. Furthermore, the CACNA1H heterozygote mice were interbred with Thy1-GFP-O mice to generate CACNA1H-/--Thy1+(KO-GFP) and CACNA1H+/+-Thy1+ (WT-GFP) mice. The density and maturity of dendritic spines of hippocampal neurons were observed.@*RESULTS@#In the sociability test session of the three-chamber test, the KO mice spent more time in the chamber of the stranger mice than in the object one (F1, 14=95.086, P < 0.05; Post-Hoc: P < 0.05), without any significant difference for the explored preference index between the two groups (t=1.044, P>0.05). However, in the social novelty recognition test session, no difference was observed between the time of the KO mice spend in the chamber of new stranger mice and the stranger one (F1, 14=18.062, P < 0.05; Post-Hoc: P>0.05), and the explored preference index of the KO mice was less than that of the control group (t=2.390, P < 0.05). In the open field test, the KO mice spent less time in the center of the open field apparatus than the control group (t=2.503, P < 0.05), but the self-grooming time was significantly increased compared with the control group (t=-2.299, P < 0.05). Morphological results showed that the brain weight/body weight ratio (t=0.356, P>0.05) and brain size (t=-0.660, P>0.05) of the KO mice were not significantly different from those of the control group, but the number of neurons were significantly reduced in hippocampal dentate gyrus compared with the control group (t=2.323, P < 0.05). Moreover, the density of dendritic spine of dentate gyrus neurons in the KO-GFP mice was significantly increased compared with the control group (t=-2.374, P < 0.05), without any significant difference in spine maturity (t=-1.935, P>0.05).@*CONCLUSION@#CACNA1H KO mice represent autistic-like behavior, which may be related to the decrease in the number of neurons and the increase in the density of dendritic spine in the dentate gyrus.

Construction of a Spink5 conditional knockout mouse model and analysis of its phenotype / 中华皮肤科杂志

Objective:To construct a serine protease inhibitor Kazal type-5 (Spink5) conditional knockout mouse model, and to identify its phenotype.Methods:B cell-specific Spink5 conditional knockout mice of genotype Mb1 cre/+Spink5 floxp/floxp were constructed by using clustered regularly interspaced short palindromic repeats (CRISPR) /CRISPR-associated protein 9 (Cas9) technology, and served as the knockout group. Mice of genotype Mb1 +/+Spink5 floxp/floxp served as the control group. The mice of genotype Mb1 cre/+Spink5 floxp/floxp or Mb1 +/+Spink5 floxp/floxp were sacrificed when they were 4 to 6 weeks old, splenic mononuclear cells were isolated, and B lymphocytes and non-B lymphocytes were sorted by flow cytometry and fluorescence-activated cell sorting. Genotype identification was performed by PCR, and protein expression of lymphoepithelial Kazal-type-related inhibitor (LEKTI) was determined by Western blot analysis. Skin tissues were resected from the mice, and subjected to hematoxylin-eosin staining for measuring the epidermal thickness. Immunofluorescence staining was performed to determine fluorescence intensity of LEKTI protein in the mouse skin tissues. Paired t test or two-independent-sample t test was used for comparisons between groups. Results:Genotype identification results demonstrated that the stable B lymphocyte-specific Spink5 conditional knockout mouse model was successfully constructed. Western blot analysis revealed that the relative protein expression of LEKTI in the B lymphocytes in the knockout group was 0.01 ± 0.02, which was significantly lower than that in the non-B lymphocytes in the knockout group (0.66 ± 0.11, t = 9.99, P < 0.001) , and that in the B lymphocytes in the control group (1.08 ± 0.13, t = 13.78, P < 0.001) . Among 39 mice in the knockout group, 4 presented with dry skin and scattered scaly hypertrophic maculopapules. The epidermal thickness of the lesional skin tissues in the knockout group was 90.42 ± 21.31 μm, significantly higher than that of the non-lesional skin tissues in the knockout group (29.71 ± 3.63 μm, t = 5.05, P = 0.002) and that of normal skin tissues in the control group (12.42 ± 2.21 μm, t = 6.74, P < 0.001) . Immunofluorescence staining showed no significant difference in the fluorescence intensity of LEKTI protein among the lesional skin tissues (46.21 ± 1.21) , non-lesional skin tissues (46.62 ± 2.13) in the knockout group and normal skin tissues in the control group (47.69 ± 1.71, P > 0.05) . Conclusion:The B lymphocyte-specific Spink5 conditional knockout mouse model was successfully constructed, which provides a basis for further exploring mechanisms underlying skin barrier defects and immune dysfunction in Netherton syndrome.

Effect of tumor necrosis factor-related apoptosis-inducing ligand gene knock-out on the gut microbiota in mice with dextran sodium sulphate induced colitis / 中华消化杂志

Objective@#To investigate the influence of tumor necrosis factor-related apoptosis-inducing ligant (TRAIL) deficiency on mice colitis and the gut microbiota composition by inclding the expermental colitis model in tumor necrosis factor-related apoptosis-inducing ligand gene knockout (TRAIL-/-) mice.@*Methods@#C57BL/6 TRAIL-/- mice and wild type (WT) mice were selected and assigned into TRAIL-/- control group (eight mice), TRAIL-/- colitis group (16 mice), WT control group (eight mice) and WT colitis group (16 mice). The mice of two colitis groups were oral administrated with 3.5% dextran sulphate sodium (DSS) in drinking water for seven consecutive days to induce experimental colitis model. The severity of colitis was evaluated by clinical appearance and histopathological examination. The colonic tissue samples of mice were collected and microbiota profile was analyzed by 16S rDNA sequencing method. USEARCH software and R language were used to analyze the difference of gut microbiota among TRAIL-/- control group, TRAIL-/- colitis group, WT control group and WT colitis group. T test and Mann-Whitney U test were used for statistical analysis.@*Results@#After modeling, the disease activity index (DAI) of WT colitis mice and TRAIL-/- colitis mice both gradually increased over time. Furthermore, compared with colitis mice, TRAIL-/- colitis mice developed body weight loss, diarrhea and hemafecia earlier. On the seventh day after modeling, the percentage of body weight loss of TRAIL-/- colitis mice and WT colitis mice was (28.98±2.84)% and (17.87±3.70)%, respectively; and the difference was statistically significant (t=9.53, P<0.01). The length of colon of TRAIL-/- colitis mice was shorter than that of WT colitis mice ((4.63±0.28) cm vs. (6.02±0.41) cm), and the difference was statistically significant (t=11.20, P<0.01). The DAI of TRAIL-/- colitis mice was higher than that of WT colitis mice (3.00±0.00 vs. 2.32±0.05), and the difference was statistically significant (t=54.40, P<0.01). The histological score of TRAIL-/- colitis mice was higher than that of WT colitis mice (6.19±0.25 vs. 3.87±0.22), and the difference was statistically significant (t=27.87, P<0.01). Under the microscope, colonic mucosal epithelial injury, crypt structure destruction and inflammatory cell infiltration were more obvious in TRAIL-/- colitis mice than in WT colitis mice. The alpha diversity of colonic flora was more significant in TRAIL-/- colitis group compared with that of WT colitis group. At the family level, the relative richness of Deferribacteraceae, Ruminococcaceae, Rikenellaceae, F16 and Paraprevotellaceae significantly increased in TRAIL-/- colitis group, but the relative richness of Enterococcaceae obviously reduced ((19.839±19.991)% vs. (7.224±11.241)%, (3.564±2.543)% vs.(2.861±3.821)%, (0.123±0.066)% vs. (0.068±0.049)%, (0.032±0.033)% vs. (0.006±0.011)%, (0.153±0.098)% vs. (0.062±0.054)% and (0.013±0.027)% vs. (0.054±0.121)%, respectively; U=51, 69, 53, 35, 49 and 69, respectively; P<0.01 and 0.05, respectively). In addition, at the genus level the relative richness of Oscillospira, Mucispirillum and Cytophaga in TRAIL-/- colitis group remarkably elevated, and the relative richness of Enterococcus significantly decreased ((2.363±2.147)% vs. (1.813±2.847)%, (19.839±19.991)% vs. (7.223±11.241)%, (0.104±0.153)% vs. (0.046±0.069)% and (0.076±0.049)% vs. (0.135±0.074)%, respectively; U=70, 51, 66 and 65, respectively; P <0.05 and 0.01, respectively).@*Conclusion@#TRAIL deficiency aggravate DSS-induced colitis, and increase the alpha diversity of colonic microbiota in colitis mice.

Study on Role and Mechanism of Claudin-2 in Formation of Cholesterol Gallstone / 胃肠病学

Background: Claudin protein family is an important component for construction of tight cell junction. Claudin-2 is a forming protein of paracellular channel and is highly expressed in hepatocytes and bile duct cells, which has selective permeability of water molecules and cations. Claudin-2 plays a vital role in the physiological regulation of digestive and urinary systems. Aims: To investigate the role and mechanism of claudin-2 in formation of cholesterol gallstone and bile secretion. Methods: Liver and gallbladder tissues from claudin-2 knockout (Cldn-2-/-) and wild type (Cldn-2+/+) mice were collected. Expressions of claudin family protein were determined by Western blotting. HE staining, immunofluorescence staining, electron microscope were used to analyze the effect of claudin-2 gene knockout on liver and gallbladder tissue structure. Regulatory roles of claudin-2 in bile component and flow were analyzed. Results: Claudin family proteins were highly expressed in liver and gallbladder tissue in Cldn-2+/+ mice. No significant difference in structure of liver and gallbladder tissue was found between Cldn-2-/- mice and Cldn-2+/+ mice. Compared with Cldn-2+/+ mice, bile flow rate was significantly decreased (P<0.05), concentration of bile was significantly increased (P<0.05), and contents of bile acid, cholesterol, bilirubin, phospholipid in liver and gallbladder bile were significantly increased in Cldn-2-/- mice (P<0.05). Conclusions: Claudin-2 regulates paracellular water flow which is required for proper regulation of bile composition and flow. Dysregulation of this process increases the susceptibility to cholesterol gallstone related diseases in mice.

Effect of tumor necrosis factor-related apoptosis-inducing ligand gene knock-out on the gut microbiota in mice with dextran sodium sulphate induced colitis / 中华消化杂志

Objective To investigate the influence of tumor necrosis factor-related apoptosis-inducing ligant (TRAIL) deficiency on mice colitis and the gut microbiota composition by inclding the expermental colitis model in tumor necrosis factor-related apoptosis-inducing ligand gene knockout ( TRAIL-/-) mice. Methods C57BL/6 TRAIL-/-mice and wild type (WT) mice were selected and assigned into TRAIL-/-control group (eight mice), TRAIL-/-colitis group (16 mice), WT control group (eight mice) and WT colitis group (16 mice).The mice of two colitis groups were oral administrated with 3.5% dextran sulphate sodium (DSS) in drinking water for seven consecutive days to induce experimental colitis model .The severity of colitis was evaluated by clinical appearance and histopathological examination .The colonic tissue samples of mice were collected and microbiota profile was analyzed by 16S rDNA sequencing method.USEARCH software and R language were used to analyze the difference of gut microbiota among TRAIL-/-control group, TRAIL-/-colitis group, WT control group and WT colitis group .T test and Mann-Whitney U test were used for statistical analysis . Results After modeling, the disease activity index (DAI) of WT colitis mice and TRAIL-/-colitis mice both gradually increased over time .Furthermore, compared with colitis mice, TRAIL-/-colitis mice developed body weight loss, diarrhea and hemafecia earlier .On the seventh day after modeling , the percentage of body weight loss of TRAIL-/-colitis mice and WT colitis mice was (28.98 ±2.84)%and (17.87 ±3.70)%, respectively; and the difference was statistically significant (t＝9.53, P?0.01).The length of colon of TRAIL-/-colitis mice was shorter than that of WT colitis mice ((4.63 ±0.28) cm vs.(6.02 ±0.41) cm), and the difference was statistically significant (t＝11.20, P?0.01).The DAI of TRAIL-/-colitis mice was higher than that of WT colitis mice (3.00 ±0.00 vs.2.32 ±0.05), and the difference was statistically significant (t ＝54.40, P? 0.01).The histological score of TRAIL-/-colitis mice was higher than that of WT colitis mice (6.19 ±0.25 vs. 3.87 ±0.22), and the difference was statistically significant (t ＝27.87, P?0.01).Under the microscope, colonic mucosal epithelial injury , crypt structure destruction and inflammatory cell infiltration were more obvious in TRAIL-/-colitis mice than in WT colitis mice.The alpha diversity of colonic flora was more significant in TRAIL-/-colitis group compared with that of WT colitis group .At the family level, the relative richness of Deferribacteraceae, Ruminococcaceae, Rikenellaceae, F16 and Paraprevotellaceae significantly increased in TRAIL-/-colitis group, but the relative richness of Enterococcaceae obviously reduced ((19.839 ±19.991)%vs. (7.224 ±11.241)%, (3.564 ±2.543)% vs.(2.861 ±3.821)%, (0.123 ±0.066)% vs.(0.068 ± 0.049)%, (0.032 ±0.033)% vs.(0.006 ±0.011)%, (0.153 ±0.098)% vs.(0.062 ±0.054)% and (0.013 ±0.027)%vs.(0.054 ±0.121)%, respectively; U＝51, 69, 53, 35, 49 and 69, respectively; P? 0.01 and 0.05, respectively).In addition, at the genus level the relative richness of Oscillospira, Mucispirillum and Cytophaga in TRAIL-/-colitis group remarkably elevated , and the relative richness of Enterococcus significantly decreased ((2.363 ±2.147)% vs.(1.813 ±2.847)%, (19.839 ±19.991)% vs.(7.223 ± 11.241)%, (0.104 ±0.153)%vs.(0.046 ±0.069)% and (0.076 ±0.049)% vs.(0.135 ±0.074)%, respectively; U＝70, 51, 66 and 65, respectively; P ?0.05 and 0.01, respectively).Conclusion TRAIL deficiency aggravate DSS-induced colitis, and increase the alpha diversity of colonic microbiota in colitis mice .

Effect of Hic-5 gene knockout on NF-κB/p65 expression and CCl4-induced liver fibrosis degree in mice / 临床肝胆病杂志

@#ObjectiveTo investigate the effect of Hic-5 gene knockout on NF-κB/p65 expression and liver fibrosis. MethodsTen wild-type male C57BL/6 mice were randomly divided into wild-type control group (WT-Control group with 5 mice) and wild-type experimental group (WT-CCl4 group with 5 mice), and ten male C57BL/6 mice with Hic-5 gene knockout were randomly divided into Hic-5 knockout control group (Hic-5 KO-Control group with 5 mice) and Hic-5 knockout experimental group (Hic-5 KO-CCl4 group with 5 mice). The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. Picrosirius red staining was used to observe collagen deposition in liver tissue. Immunohistochemistry was used to measure the expression of alpha-smooth muscle actin (α-SMA) and p65 protein, and real-time quantitative PCR was used to measure the mRNA expression of α-SMA, collagen 1, and p65 in liver tissue. The primary hepatic stellate cells of mice were isolated and stimulated with different concentrations of TGF-β1, and then real-time quantitative PCR was used to measure the mRNA expression of α-SMA, collagen 1, and p65 in primary hepatic stellate cells. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t-test was used for further comparison between two groups. ResultsPicrosirius red staining showed that compared with the WT-CCl4 group, the Hic-5 KO-CCl4 group had a significant reduction in collagen fibers in liver tissue (P＜0.001). Measurement of serum ALT and AST showed that there were significant differences in ALT and AST between the WT-Control group, the WT-CCl4 group, the Hic-5 KO-Control group, and the Hic-5 KO-CCl4 group (F=22.85 and 25.15, both P＜0.001), and the Hic-5 KO-CCl4 group had significantly lower serum levels of ALT and AST than the WT-CCl4 group (both P＜0.05). Immunohistochemistry showed that there were significant differences in the expression levels of α-SMA and p65 protein in liver tissue between the WT-Control group, the WT-CCl4 group, the Hic-5 KO-Control group, and the Hic-5 KO-CCl4 group (F=207.10 and 98.16, both P＜0.001), and the Hic-5 KO-CCl4 group had significantly lower expression of α-SMA and p65 protein in liver tissue than the WT-CCl4 group (both P＜0.01). The results of real-time quantitative PCR showed that there were significant differences in the relative mRNA expression of α-SMA, collagen 1, and p65 in liver tissue between the WT-Control group, the WT-CCl4 group, the Hic-5 KO-Control group, and the Hic-5 KO-CCl4 group (F=41.62, 13.93, and 98.16, all P＜0.001), and the Hic-5 KO-CCl4 group had significantly lower relative mRNA expression of α-SMA, collagen 1, and p65 in liver tissue than the WT-CCl4 group (all P＜0.05). After the primary hepatic stellate cells were stimulated by TGF-β1 at concentrations of 0, 5, and 10 ng/ml, there were significant differences in the relative mRNA expression of α-SMA, collagen 1, and p65 between the WT 0 ng/ml group, the WT 5 ng/ml group, the WT 10 ng/ml group, the KO 0 ng/ml group, the KO 5 ng/ml group, and the KO 10 ng/ml group (F=53.9, 75.82, and 52.41, all P＜0.001), and the Hic-5 KO group had significantly lower relative mRNA expression of α-SMA, collagen 1, and p65 than the WT group (all P＜0.01). ConclusionHic-5 knockout inhibits NF-κB/p65 expression and hepatic stellate cell activation and alleviates CCl4-induced liver fibrosis.

Relationship of TN-C, MMP-9 and TGF-β1 with aorta atherosclerotic plaues in mice / 中华老年心脑血管病杂志

Objective To study the relationship of TN-C,MMP-9 and TGF-β1 expression with aorta atherosclerotic plaue stability in mice on long-term high fat diet.Methods Fifty male apo E/ mice on high fat diet served as an experimental group and 50 male C57BL/6 mice on basic diet served as a control group.The morphology of plaques was observed with HE staining and the expression of TN-C,MMP-9 and TGF-β1 was detected with immunohistochemical staining.Results The serum TC and LDL-C levels were significantly higher in experimental group than in control group at weeks 16,24,32 and 40 (P＜0.05).The serum TG level was significantly higher in experimental group than in control group at week 16 (P＜0.05) and was significantly lower in experimental group than in control group at week 40 (P＜0.05).With the lengthening of the feeding time,the plaque area,the ratio of plaque to lumen area,and the expression of TN-C and MMP-9 increased gradually,but the expression of TGF-β1 decreased gradually (P＜0.05).Conclusion The expression of TN-C,MMP-9 and TGF-β1 can show the stability of atherosclerotic plaques.

Expermental study on hepatic ischemia and reperfusion injury in Rag1 and Rag2/IL2rγ knockout mice / 国际外科学杂志

Objective To explore the effect of lymphocytes on the innate immune cells in Rag1 and Rag2/IL2rγ gene knockout mice after hepatic ischemia and reperfusion injury (HIRI).Methods C57BL/6 mice (n =10),Rag1 knockout mice (n =10) and Rag2/IL2rγ knockout mice (n =10) were respectively divided into sham group and hepatic ischemia-reperfusion injury group by simple randomization,5 mice in each group.By using the model of hepatic ischemia-reperfusion injury in mice,changes of intrahepatic immune cells were detected by flow cytometry.Hepatic ischemia and reperfusion injury and changes of intrahepatic cell subsets were observed in immune system-deficient mice,both Rag1 and Rag2/IL2rγ knockout.Measurement data were expressed as ((x) ±s),and analyzed using independent samples t test.Results Flow cytometry results showed that immune cells,including NK cells,NKT cells,CD4+T cells,DNT cells,Kupffer cells,BMMs and neutrophils were increased after HIRI.Compared with sham group,Rag1 knockout mice displayed markedly increased proportion of Kupffer cells,BMMs and neutrophils after HIRI.And decreased serum ALT levels [from (1 776.25 ± 219.37) U/L to (932.33 ±58.77) U/L,P=0.003,t =7.350] and less hepatocellular necrosis were exhibited in Rag1 knockout mice after HIRI,comparing to C57BL/6 HIRI group.In addition,increased neutrophils were still observed in Rag2/IL2rγ knockout mice after HIRI,without increased proportion of Kupffer cells and BMMs.Compared with Rag1 knockout mice,ALT levels were further decreased from (932.33 ± 58.77) U/L to (309.00 ± 163.53) U/L (P=0.002,t =6.182) in Rag2/IL2rγ knockout mice.Conclusion Both Rag1 and Rag2/IL2rγ knockout mice exhibite less liver injury after HIRI comparing with C57BL/6 mice,indicating that T cells and NK cells aggravate the liver injury.Moreover,T cells do not affect the recruitment of Kupffer cells,BMMs and neutrophils,but regulate the recruitment of NK cells,while NK cells contribute to the activation of Kupffer cells and BMMs,but not neutrophil influx.

Construction of BRCC3 gene knockout mice and preliminary analysis of the pheno-type / 军事医学

Objective To construct BRCC3(BRCA1/BRCA2-containing complex subunit 3)gene knockout mice and preliminarily study the phenotypes.Methods Using the Cas9/sgRNA-Mediated genome Editing, the BRCC3 knockout mouse models were constructed.Genomic DNAs of mouse tail tissues were extracted and identified, the genotypes of mice were determined at the DNA level,and RNAs and proteins of tissues, such as the heart, liver, spleen, lung, kidney of mice were extracted and the expression of BRCC3 gene was detected by real-time-PCR and Western blotting(WB).The trend of relative body mass change and indexes that might affect the growth development and metabolism were observed. Major organs were hematoxylin-eosin(HE)stained and observed.The routine blood test of peripheral blood of mice was conducted.Results The mouse model of BRCC3 knockout was successfully constructed.BRCC3 knockout mouse survived and were fertile, indexes of blood lipid and liver function were normal, organs were not degenerative and indexes of peripheral blood in routine blood test were all in the normal range.The relative body mass of BRCC3 knockout mice was higher than that of wild type mice,and the level of serum cholesterol was increased.Conclusion BRCC3 may be involved in relative body mass regulation and cholesterol metabolism in mice.

Effects of apolipoprotein E deficiency on sphingosine-1-phosphate distribution in plasma and lipoproteins of mice / 中华心血管病杂志

Objective@#To investigate the effects of apolipoprotein E deficiency (Apo E-/-) on plasma and lipoprotein distribution of sphingosine-1-phosphate (S1P) in mice.@*Methods@#Five male or female Apo E-/- or wild type (WT) mice were fed with chow diet and sacrificed at 32-week-age and plasma was collected. The constituents of lipoprotein(very low density lipoprotein (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL)) were separated by ultracentrifuge. The protein concentration of constituents was detected by BCA protein quantitative kit, and the S1P concentration in plasma and various lipoprotein constituents was detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Western blot was used to determine the plasma, liver, and kidney protein expression of apolipoprotein M(Apo M), which is considered as specific ligand of S1P.The S1P concentration in plasma and various constituents of lipoprotein in the Apo E-/- mice was compared to respective WT mice.@*Results@#(1)Plasma S1P content was significantly higher in the Apo E-/- groups than that of WT groups (male: (535.7±78.5)nmol/L vs. (263.3±22.0)nmol/L; female: (601.1±64.0)nmol/L vs. (279.0±33.9)nmol/L; all P<0.01). (2) Compared with WT mice, S1P content in non-HDL(LDL+ VLDL) was significantly higher in Apo E-/- mice (male: (504.9±52.8)nmol/L vs. (28.7±9.0)nmol/L; female: (427.7±27.4) vs. (27.8±4.7)nmol/L; after standardization of protein concentration, male: (385.0±41.2)pmol/mg protein vs. (71.4±6.6)pmol/mg protein; female: (330.2±22.0)pmol/mg protein vs. (67.2±12.1)pmol/mg protein; all P<0.01). (3) The expression of Apo M in plasma, liver and kidney was significantly higher in Apo E-/- groups than that of WT groups(all P<0.05).@*Conclusion@#The deficiency of Apo E could lead to upregulated S1P expression in the non-HDL, the underlying mechanism might be the increased transfer of HDL into the non-HDL by Apo M-S1P.

Role of nuclear factor erythroid 2-related factor in hydrogen-induced reduction of intestinal injury in mice with sepsis / 中华麻醉学杂志

Objective To evaluate the role of nuclear factor erythroid 2-related factor (Nrf2) in hydrogen-induced reduction of intestinal injury in mice with sepsis.Methods Eighteen pathogen-free male wild type mice and 18 male Nrf2 gene knockout mice,aged 6-8 weeks,weighing 20-25 g,were studied.The mice of either type were assigned into 3 groups (n =6 each) using a random number table:sham operation group (group Sham),sepsis group (group Sep) and hydrogen group (group H2).Sepsis was induced by cecal ligation and puncture in chloral hydrate-anesthetized mice.The mice inhaled 2％ hydrogen for 1 h starting from 1 and 6 h after operation in group H2.The mice were sacrificed at 24 h after operation,and small intestinai tissues were removed for determination of the tumor necrosis factor-alpha (TNF-α),interleukin-1beta (IL-1β) and high-mobility group box 1 protein (HMGB 1) contents (by enzyme-linked immunosorbent assay),superoxide dismutase (SOD) and catalase (CAT) activities and malondialdehyde (MDA) content (using a spectrophotometer),8-iso-prostaglandin F2α (8-iso-PGF2α) content (with Multiskan Spectrum plate reader),and expression of heme oxygenase-1 (HO-1) and HMGB1 protein and mRNA (by Western blot or real-time polymerase chain reaction).Results For wild type and Nrf2 gene knockout mice:compared with group Sham,the contents of TNF-α,IL-1β,HMGB1,MDA and 8-iso-PGF2α were significantly increased,the expression of HO-1 and HMGB1 protein and mRNA was up-regulated,and the activities of CAT and SOD were decreased in group Sep (P＜0.05).For wild type mice:compared with group Sep,the levels of TNF-α,IL-1β,MDA and 8-iso-PGF2α were significantly decreased,the expression of HMGB1 protein and mRNA was down-regulated,the expression of HO-1 protein and mRNA was upregulated,and the activities of CAT and SOD were increased in group H2 (P＜0.05).For Nrf2 gene knockout mice:no significant difference was found in the parameters mentioned above between group H2 and group Sep (P＞0.05).Compared with group H2 of wild type mice,the levels of TNF-α,IL-1β,MDA and 8-iso-PGF2α were significantly increased,the expression of HMGB1 protein and mRNA was up-regulated,the expression of HO-1 protein and mRNA was down-regulated,and the activities of CAT and SOD were decreased in group H2 of Nrf2 gene knockout mice (P＜0.05).Conclusion The mechanism by which hydrogen reduces the intestinal injury is related to Nrf2 in mice with sepsis.

Effect of inducible costmulator/inducible costmulator ligand signaling pathway on hepatic fibrosis in mice infected with Schistosoma japonicum / 中华传染病杂志

Objective To analyze the effect of inducible costmulator (ICOS)/inducible costmulator ligand (ICOSL) signaling pathway on hepatic fibrosis in mice infected with Schistosoma japonicum.Methods Seventy-eight ICOSL knockout (ICOSL-KO) mice and 77 wild type C57BL/6J mice were used as experimental schistosomiasis model infected with Schistosoma japonicum.The sera of mice were collected on the day before infection (0 week),and at 4,7,12,16 and 20 weeks post infection.Then,the concentrations of hyaluronic acid (HA) and hydroxyproline (HYP) in mice sera were measured by sandwich enzyme linked immunosorbent assay (ELISA) kits.The expressions of transforming growth factor β1 (TGF-β1),α-smooth muscle actin (a-SMA) and Collagen-Ⅰ in livers from ICOSL-KO/wild type mice were assessed by immunohistochemical staining.The granulomatous pathology and fibrosis level in mice liver were dynamically observed by hematoxylin and eosin (HE) staining and Masson's staining,respectively.The difference between groups was detected by t test or x2 test when appropriate.Results After infection with Schistosoma japonicum,the levels of HA and HYP were gradually increased.In ICOSL-KO mice,the levels of HA at 7,12,16 and 20 weeks post infection were all significantly lower than those in wild type mice [(161.32±15.44) vs (186.01±21.24) ng/mL,t=2.528 2,P＜0.05; (166.73±18.18) vs (231.39±20.12) ng/mL,t=4.342 4,P＜0.05; (193.58±21.06) vs (252.51±25.29) ng/mL,t=4.003 9,P＜0.05; (253.98±24.53) vs (310.88±23.86) ng/mL,t=3.718 0,P＜0.05].Similarly,HYP levels in ICOSL-KO mice at 12,16 and 20 weeks post infection were all significantly lower than those in wild type mice (all P＜0.05).Immunohistochemical staining showed that TGF-β1,α-SMA and Collagen-Ⅰ expressions in liver of ICOSL-KO mice from 7 to 20 weeks post infection were all significantly lower than those of wild type mice (all P＜0.05).HE staining showed,the volume of liver egg granulomas of ICOSL-KO mice was significantly smaller than that of wild type C57BL/6J mice (P＜0.01).Furthermore,Masson's staining showed that the level of hepatic fibrosis in ICOSL-KO mice was lower than that in wild type mice and the fibrosis scores were statistically different between two groups (all P＜0.05).The mortality rate of the wilde type C57BL/6J mice was higher than that of ICOSL-KO mice.After 20 weeks of infection,the difference was statistically significant (55.84 ％ vs 37.18 ％,x2 =5.427,P＜0.05).Conclusions The degree of hepatic fibrosis and related indicators are obviously down-regulated in ICOSL-KO mice infected with Schistosoma japonicum.These findings suggest that ICOS/ICOSL signaling pathway has an important impact on the process of hepatic fibrosis caused by Schistosoma japonicum.

Functional analysis of platelet-derived growth factor-β receptor in self-renewal of neural stem cells / 中华神经科杂志

Objective To investigate the role of platelet-derived growth factor-β receptor (PDGFR-β) in self-renewal of neural stem cells (NSCs).Methods In this study,NSCs of subventricular zone were isolated and cultured from PDGFR-β knockout (PDGFR-β-/-) mice of postnatal day 1 (P1) and P28;the number and diameters of secondary neurospheres were calculated;using 5-bromo-2-deoxyuridine (BrdU) incorporation assay and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay,cell proliferation and survival rates were analyzed;gene expression profiles were determined by PCR-array analyses;the effect of brain-derived neurotrophic factor (BDNF) on secondary neurospheres formation was examined in these cells.Results In PDGFR-β-/-NSCs,stem cell activities,such as number (/well;P1:25.9±1.3vs117.6±3.6,t=4.236,P＜0.01;P28:13.8± 0.7vs 19.8±0.6,t=2.116,P＜0.01)and diameters (μm;P1:67.7±1.9 vs 69.1 ±2.0,t=3.211,P＜0.01;P28:33.4±0.8vs37.8±0.8,t=2.354,P ＜0.01) of secondary neurospheres,cell proliferation (％;P1:73.3 ± 2.7 vs 88.7 ± 3.6,t =2.773,P ＜ 0.05;P28:28.6 ± 9.6 vs 68.2 ± 4.5,t =6.302,P ＜ 0.05) and survival rates (％;P1:14.5 ±2.1 vs 9.3 ± 1.3,t =7.222,P ＜ 0.05),were significantly lower as compared with age-matched controls.In comparison of the same genotypic NSCs,the decrease of secondary neurosphere formation was more striking in P28 NSCs than in P1 NSCs.PCR Array analyses demonstrated that expressions of fibroblast growth factor2 and BDNF were decreased (-2.04 ± 0.25,t =2.653,P ＜ 0.05;-3.24 ± 0.37,t =1.324,P ＜ 0.05),and Noggin (2.31 ± 0.37,t =2.749,P ＜ 0.05) was increased in P1 PDGFR-β-/-NSCs as compared with P1 controls.Addition of BDNF rescued the number and diameter of secondary neurospheres in P1 PDGFR-β-/-NSCs to similar levels as controls.Conclusions PDGFR-β signaling may play a role in the selfrenewal and proliferation of NSCs.BDNF may be involved in the effects of PDGFR-β signaling in these cells.

Response of EDAG knockout mice to low-dose radiation-induced damage / 军事医学

Objective To generate the erythroid differentiation associated gene(EDAG) knockout mice and analyze their sensitivity to low dose radiation-induced damage.Methods Zinc finger nuclease technology ( ZFNs ) was used to produce the EDAG knockout mice.The low dose radiation-induced damage was evaluated by peripheral blood cell counts, DNA damage and colony formation of bone marrow cells.Wild-type and EDAG knockout mice were irradiated with 0.31 Gy/min X-ray, one minute per day for seven consecutive days, and the cumulative radiation dose was 2.17 Gy(n=7).The blood cell counts were measured by an automated hemocytometer.DNA damage was detected by immunofluorescence assay with a DNA damage marker p-H2A.x antibody (n=3).The colony formation ability of bone marrow cells was evaluated with a semi-solid culture medium(n=3).Results A model of EDAG knockout mice was established.Compared to wide type mice, white blood cell counts of EDAG knockout mice decreased significantly while the DNA damage marker p-H2A.x expression was increased on the third day after X-ray irradiation.The ability of colony-forming was reduced after 7 days of X-ray irradiation.Conclusion Our present study found that EDAG knockout mice are more sensitive to low dose radiation-induced damage as shown by decreased peripheral blood cells counts, reduced colony-forming ability of bone marrow cells, and increased DNA damage.These results suggest that EDAG knockout mice can serve as a powerful tool for evaluation of the biological effects of low-dose radiation damage.

Paracoccidioides lutzii: estudo de alguns mecanismos de patogenicidade

A paracoccidioidomicose (PCM) é uma doença granulomatosa sistêmica, causada por Paracoccidioides spp., (P. brasiliensis e P. lutzii), geograficamente, limita-se a América Latina com as áreas endêmicas estendendo-se desde o México até a Argentina, constituindo uma das micoses sistêmicas de maior incidência na região, afetando principalmente trabalhadores rurais. O maior número de pacientes com PCM tem sido reportado principalmente no Brasil, Colômbia e Venezuela. A incidência real desta micose encontra-se subestimada no Brasil e pouco se conhece em relação a nova espécie descrita - P. lutzii. A maioria dos estudos em P. lutzii foram focados em genética, especiação e na geração de novos antígenos para melhorar a especificidade e sensibilidade dos testes sorológicos. Atualmente, as preparações antigênicas tradicionais, preparadas a partir de isolados de P. brasiliensis, são ineficientes. Raros são os trabalhos focados na biologia de P. lutzii e nos fatores de virulência que podem ser comparados com P. brasiliensis nos modelos experimentais. A nossa proposta de estudo foi avaliar alguns aspectos in vitro e in vivo relacionados com a patogenicidade e destacamos: a fagocitose e a morte intracelular de P. lutzii por macrófagos, peritoneais, de camundongos Knockouts (KO) e selvagens para PRRs (TLR2, TLR4 e Dectina) e ativadores intracelulares (MyD88 e NALP3). Paralelamente a este estudo, animais foram infectados com leveduras de P. lutzii e comparados com os modelos de infecção já estabelecidos com leveduras (Pb18) e conídios (ATCCPb60855) de P. brasiliensis. Nossos dados indicam que similar ao que ocorre com P. brasiliensis a fagocitose de P. lutzii depende de TLR2, TLR4 e Dectina- 1, resultados semelhantes também foram observadas na expressão de moléculas envolvidas na co-estimulação e a apresentação de antígenos (MHC II, CD80 e CD86)...

Paracoccidioidomycosis (PCM) is a systemic granulomatous disease caused by Paracoccidioides spp. (P. brasiliensis and P. lutzii), geographically, is limited to Latin America with endemic areas from Mexico to Argentina, as one of the systemic mycoses with the highest incidence in the region, mainly affecting rural workers. The largest number of patients with PCM has been mainly reported in Brazil, Colombia and Venezuela. The true incidence of this mycosis is underestimated in Brazil and little is known about the new species described - P. lutzii. Most studies in P. lutzii were focused on genetics, speciation and the generation of new antigens to improve the specificity and sensitivity of serological tests. Currently, traditional antigenic preparations, prepared with isolates of P. brasiliensis, are inefficient. There are few studies focused on P. lutzii biology and virulence factors that can be compared with P. brasiliensis in experimental models. Our study aimed to evaluate some in vitro and in vivo aspects related to pathogenicity: phagocytosis and intracellular killing of P. lutzii by peritoneal macrophages from knockouts (KO) for PRRs (TLR2, TLR4 and Dectin) and intracellular activators (MyD88 and NALP3). In addition, animals were infected with P. lutzii yeast and compared with the well-established models of infection with yeast cells (Pb18) and conidia (ATCC Pb60855) from P. brasiliensis. Our data indicate that similarly to what happens with the phagocytosis of P. brasiliensis, P. lutzii phagocytosis is dependent on TLR2, TLR4 and Dectin-1. Other molecules, involved in co-stimulation and presentation of antigens such as MHC II, CD80 and CD86 were also shown to participate in the P. lutzii-host interaction...

Isolation and Culture of Epidermal Stem Cells from the Third Generation of Mice That Were Knocked-out of Terc / 天津医药

Objective To observe the difference in number of epidermal stem cell and its function between wild-type (WT) mice and the third generation of Terc knockout (G3Terc-/-) mice. Methods Flowcytometry was used to analyse and sort epidermal stem cells;Quantitative real-time PCR is used to analyse the relative expression level of p 21 in epider-mal stem cells;Self-renewal ability was reflected by the number of colonies formed by epidermal stem cells. Results Basal and suprabasal ratios in epidermal stem cells in WT mice were (9.56 ± 1.06)% and (1.22 ± 0.08)% respectively; basal and suprabasal ratios in epidermal stem cell in G3Terc-/-mice were (17.36±3.56)%and (2.92±0.72)%respectively. Relative p21 expression level in G3Terc-/-mice was 6.40 fold to WT mice;Number of colonies formed by WT mice epidermal stem cells were (280.20±29.81) per 104 cell, number of colonies formed by G3Terc-/-mice epidermal stem cells were (29.28±5.24) per 104 cell, which present significant difference to each other(P<0.05). Conclusion Compared to WT mice, epidermal stem cells in G3Terc-/-mice were aging.

Regulatory effect of hydrogen sulfide on endoplasmic reticulum stress and lipid metabolism in livers in apoE knockout mice / 中华老年医学杂志

Objective To investigate the regulatory effect of hydrogen sulfide (H2S) on endoplasmic reticulum stress (ERS) and lipid metabolism in livers in apoE knockout (apo E-/-) mice.Methods Male C57BL/6 J mice and homozygous apoE mice were fed with a western type diet and randomly divided into four groups:C57BL/6 J control group (injected intraperitoneally with normal saline),apoE group (injected intraperitoneally with normal saline),apoE-/-+NaHS group (injected intraperitoneally with an H2S donor NaHS 56μmol · kg-1 · d-1) and apoE-/-+ DL-propargylglycine (PPG) group (injected intraperitoneally with an acystathionine-γ-lyase inhibitor PPG 30 mg ·kg-1 · d-1).After 10 weeks,all mice were sacrificed and plasma lipids were detected.Lipid deposition was determined by oil red O staining.Glucose-regulated protein78 (GRP78),Thr-981 phosphorylated double-stranded RNA-activated protein kinase like endoplasmic reticulum kinase (PERK),subunit of eukaryotic translation initiation factor-2α (elF-2α),low density lipoprotein (LDL) receptor (LDLR),sterol regulatory element binding protein-2 (SREBP-2) in the livers were detected by Western bloting.The expressions of GRP78 and SREBP-2 mRNA were analyzed by realtime polymerase chain reaction (RT-PCR).Results Compared with C57BL/6 J control group,plasma levels of total cholesterol (TC),triglyceride (TG) and low density lipoprotein (LDL),liver lipid content and expressions of GRP-78,PERK and eIF-2α were significantly increased in apoE-/-mice,but body weight did not change.Compared with apoE-/-mice,plasma LDL level was decreased,liver lipid deposition was improved,expressions of GRP-78 and PERK in livers were increased,and the ratio of p-eIF-2α/ eIF-2α was increased in apoE-/-+NaHS group,but expression levels of SREBP-2 and LDLR in liver did not change.Conclusions H2S decreases serum LDL level and liver lipid content,and up regulates GRP78 protein and mRNA expressions,promotes PERK and eIF2α phosphorylations,improves endoplasmic reticulum function,but has no effect on the expressions of SREBP-2 and LDLR in apoE-/-mice fed with a high-fat diet.

Simvastatin and Losartan Differentially and Synergistically Inhibit Atherosclerosis in Apolipoprotein E-/- Mice

BACKGROUND AND OBJECTIVES: Since statins and angiotensin receptor blockers are a frequently prescribed combination in patients with atherosclerotic cardiovascular diseases, we tested the interactive effects of simvastatin and losartan on atherosclerosis in apolipoprotein E (apoE)-/- mice. MATERIALS AND METHODS: Apolipoprotein E-/- mice were fed a high-fat, high-cholesterol (HFHC) diet for 12 weeks, with and without simvastatin (40 mg/kg) and/or losartan (20 mg/kg). The mice were divided into 5 groups and were fed as follows: regular chow (control diet, n=5), HFHC diet (n=6), HFHC diet with losartan (n=6), HFHC diet with simvastatin (n=6), and HFHC diet with both losartan and simvastatin (n=6). RESULTS: Losartan treatment in apoE-/- mice significantly decreased atherosclerotic lesion areas in whole aortic strips stained with Oil Red O. The plaque area measured at the aortic sinus level was reduced significantly by 17% (HFHC; 346830.9+/-52915.8 microm2 vs. HFHC plus losartan; 255965.3+/-74057.7 microm2, p<0.05) in the losartan-treated group. Simvastatin and simvastatin plus losartan treatments reduced macrophage infiltration into lesions by 33% (HFHC; 183575.6+/-43211.2 microm2 vs. HFHC plus simvastatin; 120556.0+/-39282.8 microm2, p<0.05) and 44% (HFHC; 183575.6+/-43211.2 microm2 vs. HFHC plus simvastatin and losartan; 103229.0+/-8473.3 microm2, p<0.001, respectively). In mice fed the HFHC diet alone, the smooth muscle cell layer in the aortic media was almost undetectable. In mice co-treated with losartan and simvastatin, the smooth muscle layer was more than 60% preserved (p<0.05). Given alone, losartan showed a slightly stronger effect than simvastatin; however, treatment with losartan plus simvastatin induced a greater inhibitory effect on atherosclerosis than either drug given alone. Serum lipid profiles did not differ significantly among the groups. CONCLUSION: Losartan displayed anti-atherosclerotic effects in apoE-/- mice that were equivalent to or greater than the effects of simvastatin. Combined treatment with these drugs had greater effect than either drug alone.