The present study was aimed to investigate whether Gasdermin D (GSDMD)-mediated pyroptosis participated in lipopolysaccharide (LPS)-induced sepsis-associated acute kidney injury (AKI), and to explore the role of caspase-1 and caspase-11 pyroptosis pathways in this process. The mice were divided into four groups: wild type (WT), WT-LPS, GSDMD knockout (KO) and KO-LPS. The sepsis-associated AKI was induced by intraperitoneal injection of LPS (40 mg/kg). Blood samples were taken to determine the concentration of creatinine and urea nitrogen. The pathological changes of renal tissue were observed via HE staining. Western blot was used to investigate the expression of pyroptosis-associated proteins. The results showed that the concentrations of serum creatinine and urea nitrogen in the WT-LPS group were significantly increased, compared with those in the WT group (P < 0.01); whereas serum creatinine and urea nitrogen in the KO-LPS group were significantly decreased, compared with those in the WT-LPS group (P < 0.01). HE staining results showed that LPS-induced renal tubular dilatation was mitigated in GSDMD KO mice. Western blot results showed that LPS up-regulated the protein expression levels of interleukin-1β (IL-1β), GSDMD and GSDMD-N in WT mice. GSDMD KO significantly down-regulated the protein levels of IL-1β, caspase-11, pro-caspase-1, caspase-1(p22) induced by LPS. These results suggest that GSDMD-mediated pyroptosis is involved in LPS-induced sepsis-associated AKI. Caspase-1 and caspase-11 may be involved in GSDMD cleavage.
Animals ; Mice ; Acute Kidney Injury ; Caspase 1 ; Caspases/metabolism* ; Creatinine ; Lipopolysaccharides ; Mice, Knockout ; Nitrogen ; Sepsis ; Urea ; Gasdermins/metabolism*

OBJECTIVE: To investigate the changes and roles of reactive oxygen species (ROS) and nuclear factor erythroid 2-related factor 2 (Nrf2) related antioxidases during erythroid development. METHODS: Flow cytometry was used to detect the sensibility of peripheral red blood cells of wild-type mice to a strong oxidant hydrogen peroxide (H₂O₂). Erythroid cells from different developmental stages in bone marrow (BM) were obtained using fluorescence-activated cell sorter and the ROS levels were detected by flow cytometry. RT-qPCR was used to detect the changes of expression levels of Nrf2 and related antioxidases in erythroid cells from different developmental stages in BM. The ROS levels of the peripheral blood and BM nucleated erythrocytes in Nrf2 knockout mice were further examined. The expression level of Nrf2 in erythroid precursors isolated from 14.5 d embryonic liver of wild-type mice during differentiation and culture in vitro was detected. RESULTS: In the peripheral blood of wild-type mice, the ROS level of reticulocytes and mature erythrocytes treated with H₂O₂ increased about 4 times and 7 times, respectively (P<0.01). In BM erythrocytes, the ROS level gradually decreased as the cells matured (r=0.85), while the expression level of Nrf2 and its related anti-oxidative genes increased (r=0.99). The ROS levels in peripheral blood erythrocytes and BM nucleated erythrocytes of Nrf2 knockout mice were significantly increased compared with wild-type mice (P<0.01). The expression of Nrf2 increased during the early erythroid development after embryonic liver cell sorting (P<0.01). CONCLUSION The expression levels of Nrf2 and its related factors vary during erythropoiesis. Nrf2 at physiological level plays an important antioxidant role during the erythroid development.
Animals ; Mice ; Hydrogen Peroxide ; Mice, Knockout ; NF-E2-Related Factor 2/metabolism* ; Oxidative Stress ; Reactive Oxygen Species/metabolism*

Objective To investigate the long non-coding RNA(lncRNA) MRAK08838 regulates macrophage function to influence the development of asthmatic airway inflammation. Methods MRAK088388 gene knockout (MRAK088388^-/-) mouse model was prepared and allergic asthma was induced by dust mite protein Dermatophagoides farinae 1 (Der f1). The mice were sacrificed after 28 days of modeling, and serum was collected to measure IgE and IgG. The FinePointe RC system was used to measure airway hyperresponsiveness and evaluate lung function in mice. Lung tissue was taken for HE staining, and periodic acid-Schiff (PAS) staining was used to evaluate inflammatory infiltration and mucus secretion in mouse lungs. Fluorescence quantitative PCR was used to detect the expression level of lncRNA MRAK08838 in bronchoalveolar lavage fluid (BALF) cells and lung tissue of asthmatic mice. ELISA was used to detect the levels of inflammatory cytokines IFN-γ, IL-4, IL-5, IL-13, IL-10 and IL-17A. Flow cytometry was used to evaluate the phenotype of macrophages in BALF and lung tissue, as well as the proportion of neutrophils, eosinophils, and alveolar macrophages. The changes of the above indicators were detected in mice by adoptive transfer of bone marrow-derived macrophages (BMDM). Results Under the challengle of Der f1, MRAK088388^-/- mice showed reduced allergic airway inflammation, including reduced eosinophils in BALF and reduced production of IgE and IgG1. In addition, Der f1-treated MRAK088388^-/- mice had fewer M2 macrophages than wild-type asthmatic mice. Wild-type mouse BMDM (M0) and Der f1-treated MRAK088388^-/- mice also showed mild inflammatory response. Conclusion Knockout of MRAK088388 alleviates airway inflammation in asthmatic mice by inhibiting M2 polarization of airway macrophages.
Animals ; Mice ; Mice, Knockout ; RNA, Long Noncoding/genetics* ; Asthma/genetics* ; Macrophages ; Immunoglobulin E

Brain size abnormality is correlated with an increased frequency of autism spectrum disorder (ASD) in offspring. Genetic analysis indicates that heterozygous mutations of the WD repeat domain 62 (WDR62) are associated with ASD. However, biological evidence is still lacking. Our study showed that Wdr62 knockout (KO) led to reduced brain size with impaired learning and memory, as well as ASD-like behaviors in mice. Interestingly, Wdr62 Nex-cKO mice (depletion of WDR62 in differentiated neurons) had a largely normal brain size but with aberrant social interactions and repetitive behaviors. WDR62 regulated dendritic spinogenesis and excitatory synaptic transmission in cortical pyramidal neurons. Finally, we revealed that retinoic acid gavages significantly alleviated ASD-like behaviors in mice with WDR62 haploinsufficiency, probably by complementing the expression of ASD and synapse-related genes. Our findings provide a new perspective on the relationship between the microcephaly gene WDR62 and ASD etiology that will benefit clinical diagnosis and intervention of ASD.
Mice ; Animals ; Microcephaly/genetics* ; Autistic Disorder/metabolism* ; Autism Spectrum Disorder/metabolism* ; Nerve Tissue Proteins/metabolism* ; Brain/metabolism* ; Mice, Knockout ; Cell Cycle Proteins/metabolism*

To explore the effect of Mlk3 (mixed lineage kinase 3) deficiency on blood pressure, Mlk3 gene knockout (Mlk3KO) mice were generated. Activities of sgRNAs targeted Mlk3 gene were evaluated by T7 endonuclease I (T7E1) assay. CRISPR/Cas9 mRNA and sgRNA were obtained by in vitro transcription, microinjected into zygote, followed by transferring into a foster mother. Genotyping and DNA sequencing confirmed the deletion of Mlk3 gene. Real- time PCR (RT-PCR), Western blotting or immunofluorescence analysis showed that Mlk3KO mice had an undetectable expression of Mlk3 mRNA or Mlk3 protein. Mlk3KO mice exhibited an elevated systolic blood pressure compared with wild-type mice as measured by tail-cuff system. Immunohistochemistry and Western blotting analysis showed that the phosphorylation of MLC (myosin light chain) was significantly increased in aorta isolated from Mlk3KO mice. Together, Mlk3KO mice was successfully generated by CRISPR/Cas9 system. MLK3 functions in maintaining blood pressure homeostasis by regulating MLC phosphorylation. This study provides an animal model for exploring the mechanism by which Mlk3 protects against the development of hypertension and hypertensive cardiovascular remodeling.
Animals ; Mice ; Mice, Knockout ; CRISPR-Cas Systems ; Blood Pressure ; Gene Knockout Techniques ; Zygote

Our previous study has shown that p66^Shc plays an important role in the process of myocardial regeneration in newborn mice, and p66^Shc deficiency leads to weakened myocardial regeneration in newborn mice. This study aims to explore the role of p66^Shc protein in myocardial injury repair after myocardial infarction in adult mice, in order to provide a new target for the treatment of myocardial injury after myocardial infarction. Mouse myocardial infarction models of adult wild-type (WT) and p66^Shc knockout (KO) were constructed by anterior descending branch ligation. The survival rate and heart-to-body weight ratio of two models were compared and analyzed. Masson's staining was used to identify scar area of injured myocardial tissue, and myocyte area was determined by wheat germ agglutinin (WGA) staining. TUNEL staining was used to detect the cardiomyocyte apoptosis. The protein expression of brain natriuretic peptide (BNP), a common marker of myocardial hypertrophy, was detected by Western blotting. The results showed that there was no significant difference in survival rate, myocardial scar area, myocyte apoptosis, and heart weight to body weight ratio between the WT and p66^ShcKO mice after myocardial infarction surgery. Whereas the protein expression level of BNP in the p66^ShcKO mice was significantly down-regulated compared with that in the WT mice. These results suggest that, unlike in neonatal mice, the deletion of p66^Shc has no significant effect on myocardial injury repair after myocardial infarction in adult mice.
Animals ; Mice ; Body Weight ; Cicatrix/metabolism* ; Mice, Knockout ; Myocardial Infarction/genetics* ; Oxidative Stress ; Shc Signaling Adaptor Proteins/metabolism* ; Src Homology 2 Domain-Containing, Transforming Protein 1/metabolism*

OBJECTIVE: To explore the mechanism by which inositol-requiring enzyme-1α (IRE1α) regulates autophagy function of chondrocytes through calcium homeostasis endoplasmic reticulum protein (CHERP). METHODS: Cultured human chondrocytes (C28/I2 cells) were treated with tunicamycin, 4μ8c, rapamycin, or both 4μ8c and rapamycin, and the expressions of endoplasmic reticulum (ER) stress- and autophagy-related proteins were detected with Western blotting. Primary chondrocytes from ERN1 knockout (ERN1 CKO) mice and wild-type mice were examined for ATG5 and ATG7 mRNA expressions, IRE1α and p-IRE1α protein expressions, and intracellular calcium ion content using qPCR, Western blotting and flow cytometry. The effect of bafilomycin A1 treatment on LC3 Ⅱ/LC3 Ⅰ ratio in the isolated chondrocytes was assessed with Western blotting. Changes in autophagic flux of the chondrocytes in response to rapamycin treatment were detected using autophagy dual fluorescent virus. The changes in autophagy level in C28/I2 cells overexpressing CHERP and IRE1α were detected using immunofluorescence assay. RESULTS: Tunicamycin treatment significantly up-regulated ER stress-related proteins and LC3 Ⅱ/LC3 Ⅰ ratio and down-regulated the expression of p62 in C28/I2 cells (P < 0.05). Rapamycin obviously up-regulated LC3 Ⅱ/LC3 Ⅰ ratio (P < 0.001) in C28/I2 cells, but this effect was significantly attenuated by co-treatment with 4μ8c (P < 0.05). Compared with the cells from the wild-type mice, the primary chondrocytes from ERN1 knockout mice showed significantly down-regulated mRNA levels of ERN1 (P < 0.01), ATG5 (P < 0.001) and ATG7 (P < 0.001), lowered or even lost expressions of IRE1α and p-IRE1α proteins (PP < 0.01), and increased expression of CHERP (P < 0.05) and intracellular calcium ion content (P < 0.001). Bafilomycin A1 treatment obviously increased LC3 Ⅱ/ LC3 Ⅰ ratio in the chondrocytes from both wild-type and ERN1 knockout mice (P < 0.01 or 0.05), but the increment was more obvious in the wild-type chondrocytes (P < 0.05). Treatment with autophagy dual-fluorescence virus resulted in a significantly greater fluorescence intensity of LC3-GFP in rapamycin-treated ERN1 CKO chondrocytes than in wild-type chondrocytes (P < 0.05). In C28/I2 cells, overexpression of CHERP obviously decreased the fluorescence intensity of LC3, and overexpression of IRE1α enhanced the fluorescence intensity and partially rescued the fluorescence reduction of LC3 caused by CHERP. CONCLUSION IRE1α deficiency impairs autophagy in chondrocytes by upregulating CHERP and increasing intracellular calcium ion content.
Animals ; Autophagy ; Calcium/metabolism* ; Chondrocytes ; Endoplasmic Reticulum/metabolism* ; Endoribonucleases/pharmacology* ; Homeostasis ; Inositol ; Mice ; Mice, Knockout ; Protein Serine-Threonine Kinases ; RNA, Messenger/metabolism* ; Sirolimus/pharmacology* ; Tunicamycin/pharmacology*

OBJECTIVE: To investigate the roles of angiotensin-converting enzyme 2 (ACE2) in ozone-induced pulmonary inflammation and airway remodeling in mice. METHODS: Sixteen wild-type (WT) C57BL/6J mice and 16 ACE2 knock-out (KO) mice were exposed to either filtered air or ozone (0.8 ppm) for 3 h per day for 5 consecutive days. Masson's staining and HE staining were used to observe lung pathologies. Bronchoalveolar lavage fluid (BALF) was collected and the total cell count was determined. The total proteins and cytokines in BALF were determined by BCA and ELISA method. The transcription levels of airway remodeling-related indicators in the lung tissues were detected using real-time quantitative PCR. The airway resistance of the mice was measured using a small animal ventilator with methacholine stimulation. RESULTS: Following ozoneexposure ACE2 KO mice had significantly higher lung pathological scores than WT mice (P < 0.05). Masson staining results showed that compared with ozone-exposed WT mice, ozone-exposed ACE2 KO mice presented with significantly larger area of collagen deposition in the bronchi [(19.62±3.16)% vs (6.49±1.34)%, P < 0.05] and alveoli [(21.63±3.78)% vs (4.44±0.99)%, P < 0.05]. The total cell count and total protein contents in the BALF were both higher in ozone-exposed ACE2 KO mice than in WT mice, but these differences were not statistically significant (P > 0.05). The concentrations of IL-6, IL-1β, TNF-α, CXCL1/KC and MCP-1 in the BALF were all higher in ozone-exposed ACE2 KO mice than in ozone-exposed WT mice, but only the difference in IL-1β was statistically significant (P < 0.05). The transcription levels of MMP-9, MMP-13, TIMP 4, COL1A1, and TGF-β in the lung tissues were all significantly higher in ozone-exposed ACE2 KO mice (P < 0.01). No significant difference was found in airway resistance between ozone-exposed ACE KO mice and WT mice after challenge with 0, 10, 25, or 100 mg/mL of methacholine. CONCLUSION ACE2 participates in ozone-induced lung inflammation and airway remodeling in mice.
Airway Remodeling ; Angiotensin-Converting Enzyme 2 ; Animals ; Methacholine Chloride ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Ozone/adverse effects* ; Pneumonia

Skin wound healing tends to slow down with aging, which is detrimental to both minor wound recovery in daily life and the recovery after surgery. The aim of current study was to explore the effect of histone deacetylase 6 (HDAC6) on wound healing during aging. Cultured human dermal fibroblasts (HDFs) and mouse full-thickness skin wound model were used to explore the functional changes of replicative senescent dermal fibroblasts and the effect of aging on skin wound healing. Scratch wound healing assay revealed significantly decreased migration speed of senescent HDFs, and BrdU incorporation assay indicated their considerably retardant proliferation. The protein expression levels of collagen and HDAC6 were significantly decreased in both senescent HDFs and skin tissues from aged mice. HDAC6 activity inhibition with highly selective inhibitor tubastatin A (TsA) or HDAC6 knockdown with siRNA decreased the migration speed of HDFs and considerably suppressed fibroblast differentiation induced by transforming growth factor-β1 (TGF-β1), which suggests the involvement of HDAC6 in regulating fundamental physiological activities of dermal fibroblasts. In vivo full-thickness skin wound healing was significantly delayed in young HDAC6 knockout mice when compared with young wild type mice. In addition, the wound healing was significantly slower in aged wild type mice than that in young wild type mice, and became even worse in aged HDAC6 knockout aged mice. Compared to the aged wild type mice, aged HDAC6 knockout mice exhibited delayed angiogenesis, reduced collagen synthesis, and decreased collagen deposition in skin wounds. Together, these results suggest that delayed skin wound healing in aged mice is associated with impaired fibroblast function. Adequate expression and activity of HDAC6 are required for fibroblasts migration and differentiation.
Humans ; Animals ; Mice ; Aged ; Histone Deacetylase 6 ; Skin ; Wound Healing ; Cell Movement ; Collagen/pharmacology* ; Fibroblasts ; Mice, Knockout ; Cells, Cultured

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 (F_{1, 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 (F_{1, 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.
Animals ; Autistic Disorder/genetics* ; Calcium Channels, T-Type/genetics* ; Gene Knockout Techniques ; Hippocampus ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Neurons