Mice
We selected C57BL/6 wild-type(WT) and Gal-8 knockout(KO) mice and randomly divided t into four groups: (1) Sham: all mice were injected with a microsyringe without pumping collagenase; (2) ICH + Vehicle: Intraoperatively, 0.5 ul of sterile saline containing 0.075 U of type VII collagenase was injected into the striatum; (3) ICH + Thiodigalactoside(TDG): Intraoperatively, 0.5 ul of sterile saline containing 0.075 U of type VII collagenase was injected into the striatum, followed by intraperitoneal injection of TDG, 5 mg/kg, every other day for 10 days; (4) ICH + Gal-8KO: Gal-8KO mice were operated on as in the ICH group. All C57BL-6 WT mice were purchased from the Zhengzhou University Experimental Animal Center, and Gal-8KO mice were purchased from Jiangsu Ji Cui Yao Kang Science and Technology Co., Ltd. All mice were housed in SPF-grade animal rooms at the Second Affiliated Hospital of Zhengzhou University, with constant temperature, ad libitum diet and artificial circadian rhythm. All operations followed the rules and regulations established by the Animal Ethics Committee of Zhengzhou University School of Medicine.
Intracerebral Hemorrhage Model
Establishment of ICH model in mice by collagenase injection(Askenase and Sansing 2016). Mice were anesthetized with inhaled isoflurane and immobilized on an intracerebral hemorrhage localizer. After skin preparation and disinfection, the scalp is incised to ensure that the left and right skull bones are at the same level as the anterior and posterior fontanel. Taking Bregma as the origin (left side opening 2.0 mm, front 0.6 mm, depth 3.2 mm), 0.075 u (0.5 ul) collagenase was slowly injected with microinjection pump within 5 min, and stopped the injection for 10min after the injection to prevent collagenase reflux. After the surgery, slowly pull out the the microsyringe needle. Bone wax to close the bone holes and suture the scalp. After the operation, ensure that the body temperature of the mice is normal, and put them back into the cage after awakening.
Immunofluorescence
Immunofluorescence staining of frozen sections: Three days mice with intracerebral hemorrhage were selected to make frozen section. The steps were as follows: 1 ×phosphate buffer saline(PBS)for 5 min × 3 rinses; 200 µL 0.1% phosphate-buffered saline with Tween 20 (PBST) for 15 min; 0.3% PBST or 5 min × 3 rinses; incubate in 5% donkey serum solution for 1h at room temperature; 0.3% PBST for 5 min × 2 rinses; the first antibody (GFAP, Iba-1, MPO) was added at 4℃ overnight; the second antibody (Cy3 or 488) was added at room temperature for 1h without light, and then 0.3% PBST for 10 min × 3 rinses .Finally, put the brain slice on the slide and dry it away from light, put 1–2 drops of 5% DAPI solution on the slide, cover the coverslip, and dry it away from light at room temperature.. The cells were observed and photographed using a confocal microscope.
Immunofluorescence staining of paraffin sections: After placing the tissue sections in the oven at 60℃ for 30 min, then put the paraffin sections into xylene Ⅰ, xylene Ⅱ, anhydrous ethanol Ⅰ, anhydrous ethanol Ⅱ, 95% ethanol, 80% alcohol, 75% alcohol in turn, and DDH2O for dewaxing; then place in citric acid antigen repair solution for antigen repair, draw water-blocking circles, add 5% BSA to the circles for closure, followed by primary antibody (Galectin 8/LGALS8 Rabbit mAb ABclonal) and incubate overnight at 4°C. Fluorescent secondary antibody (FITC) was added after PBS washing, and the tissue sections were incubated with the same amount of BSA. Next, tissue sections were incubated in the dark for 1 hour, then repeatedly incubated with NEUN Mouse Monoclonal Antibody and CY3 Antibody, followed by DAPI staining and fluorescence microscopy photography.
Brain Water Content
The mice were anesthetized intraperitoneally with 0.3% pentobarbital sodium. After the mice were rapidly cervically dislocated and executed, the brains were rapidly separated to obtain bilateral cerebral hemispheres and cerebellum, and the cerebral hemispheres were cut into the left and right hemispheres along the longitudinal fissure and placed on a weighed tin foil. The brain tissues were immediately weighed using an electronic molecular balance, which was the Wet Weight (WW), and then quickly baked in an oven at 100°C for at least 24 h. When the weight no longer changed, they were removed and weighed again to obtain the Dry Weight (DW), and then the brain tissue water content was calculated according to the Eliot formula: Brain Water Content (BWC) = (WW-DW)/WW × 100%.
Brain Swelling And Hematoma Volume
Frozen sections of 50um from each group of mice were stained with LFB/CV, and then the volume of cerebral hematoma and the degree of cerebral swelling were counted. The specific calculation formula was as follows: brain hemorrhage volume/residual lesion volume = the sum of hemorrhage area at each level × section thickness; brain swelling degree = (hemorrhage side cerebral hemisphere volume - contralateral cerebral hemisphere volume)/hemorrhage side volume × 100%.
Western Blotting
Western blotting
After the mice were decapitated, the brain tissue around the hematoma was taken, weighed, scissors were used to cut up the brain tissue, and then a grinding rod was used to grind the brain tissue, after which the pre-prepared cell lysis solution was added to the EP tube and the ice bath was applied for 10 minutes. Then Ultrasound 1.5s, interval 2.9s, time 1min. Cryogenic Ultracentrifuge at 4,000 rpm for 20 minutes. The proteins in the supernatant were collected for protein blotting analysis. The same amount of protein is transferred to PDVF membrane by electrophoresis. Seal PDVF membranes with 5% skim milk for 1 hour at room temperature, then incubate overnight at 4°C in the refrigerator with antibodies (Raf-1 monoclonal antibody (1:1000), MCP-1 mouse monoclonal antibody (1:1000), ERK1/2 rabbit Polyclonal antibody (1:1000), phospho-ERK1/2antibody affinity (1:1000), mouse anti TNF-α monoclonal antibody, IL-10 mouse antibody, HMGB-1 Rabbit Polyclonal antibody, TGF-β1 rabbit polyclonal antibody). Then incubate the secondary antibody (HRP-labeled goat anti-rabbit, HRP-labeled goat anti-mouse) for 2h, Tris-Buffered Saline with Tween 20(TBST) rinse and ECL ultrasensitive luminescent solution development exposure.
Statistical analysis
GraphPad Prism 7 software was used to analyze and plot all experimental data, and data are presented as mean ± standard error (mean ± SEM). Comparisons between groups were made using Student's t-test or one-way ANOVA for normally distributed continuous variables. When ANOVA showed significant differences, post hoc Bonferroni test was used for pairwise comparisons. A statistically significant difference is indicated at P < 0.05.