C57 mice

A total of 20 female C57 mice, raised in the school SPF animal house, were obtained from Charles River, Beijing, and the experiment was approved by Xi’an Jiaotong University Ethics Committee. A 100 μL amount of fresh MC38 cells (5 × 10⁵ per mice) was subcutaneously inoculated into dorsal flanks of (4~5 weeks) C57 mice. Mice bearing MC38 tumor (Volume = 50 mm³) were randomly divided into 4 groups (n = 4): control (PBS), PD1, GdOFBAu, GdOFBAu + PD1. Drug treatment was administered 5 times intraperitoneally every 2 days (PD1 5 mg/kg per mice, GdOFBAu 2 mg/kg per mice). Tumor volume and the weight of mice were documented in the notebook, measured daily by vernier caliper and scales, respectively. Histology and immunostaining were measured as per our previous lab report [45 (link)].

6–8 weeks old C57 mice (Charles River Laboratories, Beijing, China) were housed in specific pathogen-free conditions. The mice used in current study are one inbred strain of C57BL/6J which had been exposed to various stimulations before. This strain is more susceptible to colon cancer development under AOM/DSS stimulation (data not published and under preparation for publication). The study was approved by the Research Ethics Committee of Cancer Hospital of China Medical University. Mice were housed in the pathogen free region and monitored daily during the experiments and the mice would be sacrificed when the weight loss is more than 20%. Mice were anesthetised with an intraperitoneal injection of ketamine 100 mg/kg and xylazine 10 mg/kg.
For induction of colonic tumors, mice were first administered an intraperitoneal injection of azoxymethane (7.4mg/kg, Sigma-Aldrich, USA); one week later, 1% DSS was first administered for 7 days in drinking water, then followed by drinking distilled water for 3 weeks. Finally the mice were killed. All polypoid or flat elevated lesions that developed were histo-pathologically counted by observation of a longitudinal paraffin section with H&E staining. Tumor size was measured with fine digital calipers and calculated by the following formula: tumor volume =0.5 × width² × length.

Eight female C57 mice aged 8 weeks were purchased from Charles River Laboratories (Shanghai, China), and they were housed in the cage with food and drink, at room temperature (22 ± 1°C), and with day and night alternation for 12 h/12 h. The mice were randomly divided into the normal group (n = 4) and osteoporosis group (n = 4). Mice in the osteoporosis group were treated daily with retinoic acid gavage (70 mg/kg retinoic acid, vegetable oil solvent), while the mice in the normal group were treated daily with control solvent gavage (vegetable oil solvent). Fifteen days later, a heparin sodium capillary tube was used to collect 500 μl whole blood from orbits of all of the mice, and the mice would be killed after that. Based on the instructions of the manufacturer, the EasySep™ Mouse Monocyte Isolation Kit (STEMCELL, Canada) was used to extract PBMC from the whole blood collected from the mice. All of the mouse-related assays were approved by the Animal Ethics Committee of Changshu Hospital Affiliated to Nanjing University of Chinese Medicine.

Experiments were performed on 20 C57 mice, of either sex (Charles River Laboratories, Saint-Constant, QC, Canada), weighing 20–30 g. Their living conditions were strictly controlled by laboratory and facility staff. They were housed in cages with food and water available ad libitum. All manipulations and procedures were in accordance with Canadian Council on Animal Care guidelines and were approved by the Université du Québec à Trois-Rivières Animal Care Committee. The mice were randomly assigned to 1 of 3 groups in acute, terminal experiments to evaluate the effect of buspirone on the H-reflex: a group (N = 8) exposed to buspirone, a group (N = 7) exposed to 5-HT_1A antagonist NAD-299 and buspirone, and controls (N = 5) treated with saline.

All animal studies were conducted in compliance with Institutional Animal Care and Use Committee approval. C57 mice were purchased from Charles River Laboratory (Wilmington, NC). B16/F10 melanoma-bearing C57 mice were generated according to our previous publication [21 (link)]. Each melanoma-bearing mouse was injected with 0.037 MBq of ⁶⁷Cu-NOTA-PEG₂Nle-CycMSH_hex or ⁶⁷Cu-NOTA-GGNle-CycMSH_hex via the tail vein. The tumor uptake specificity of ⁶⁷Cu-NOTA-PEG₂Nle-CycMSH_hex and ⁶⁷Cu-NOTA-GGNle-CycMSH_hex was determined by co-injecting 10 μg (6.07 nmol) of unlabeled NDP-MSH. Mice were sacrificed at 0.5, 2, 4, and 24 h post-injection, and tumors and organs of interest were harvested, weighed, and counted. The blood value was taken as 6.5% of the whole-body weight.
The melanoma imaging property of ⁶⁷Cu-NOTA-PEG₂Nle-CycMSH_hex was further examined in B16/F10 melanoma-bearing C57 mice. Each mouse was injected with 7.4 MBq of ⁶⁷Cu-NOTA-PEG₂Nle-CycMSH_hex via the tail vein. Imaging studies were performed 4 h post-injection. Reconstructed SPECT data was visualized using VivoQuant (Invicro, Boston, MA, USA).

Six- to eight-week-old male C57 mice were purchased from Charles River (Beijing, China) and kept under SPF conditions (12 h light/dark cycle) at a temperature of 24°C ± 2°C and 50%–60% humidity. Mice were provided water and food freely. The animal experiment was approved by the Animal Health Research Institute of Guangdong Academy of Agricultural Sciences (ethics no. SPF2020034). After a 1-week quarantine period, mice were randomly divided into the following groups: 1) control group (CTL), 2) COPD model group (MOD), 3) COPD + roflumilast (POS group, 0.5 mg/kg/d), 4) COPD + BFHX low-dose group (low group, 1.9 g/kg/d, based on the clinical dose), and 5) COPD + BFHX high-dose group (high group, 3.8 g/kg/d), n = 9 per group. All groups, except the CTL group, received cigarette smoke (CS) exposure and lipopolysaccharide (LPS) instillation, as described previously (Guan et al., 2020 (link)). Mouse airways were instilled with PBS or LPS (75 μg in 50 μL) on experimental days 1 and 14; all mice, except the CTL group, received CS exposure for 4 h with 4 h intervals. The animals were orally administered on the 61st day of the experiment for 30 days, the weights of the animals were recorded, and their states, including their hair status and movement, were observed. After administration, the animal was harvested for further analysis (n = 5–6 mice per group were analyzed).