Hematoxylin eosin h e

The animals were sacrificed under anesthesia, and the specimens, including the first molar and its surrounding periodontal tissue, were separated, fixed in 4% paraformaldehyde for 48 h, and decalcified in 12.5% ethylene diamine tetraacetic acid (EDTA, Solarbio) (pH 7.3–7.5) for up to 8 weeks. After dehydration and hyalinization, the specimens were embedded in paraffin. A series of buccal-lingual sections (5 μm thick) paralleling the long axis of the teeth were obtained. Sections that passed through the center of the middle root of the first molar were stained with hematoxylin-eosin (HE) (Solarbio) and modified Masson’s trichrome (Solarbio) and were then subjected to immunohistochemistry according to the manufacturer’s instructions. The antibodies used were as follows: mouse monoclonal anti-bone sialoprotein (BSP)-II (1:100, Santa Cruz Biotechnology, Dallas, TX, USA), mouse monoclonal anti-Runt-related transcription factor 2 (Runx2) (1:200, Abcam, Cambridge, MA, USA), rabbit polyclonal anti-tumor necrosis factor (TNF)-α (1:100), anti-interleukin (IL)-1ß (1:200, Abcam), and anti-IL-10 (1:100, Abcam) primary antibodies. A biotin-labeled goat anti-mouse/rabbit IgG complex was the secondary antibody (SPlink detection kit; ZSGB-BioTech, Beijing, China). Immunohistochemical staining was performed with a diaminobenzidine kit (ZSGB, Bio Tech).

Polyvinyl alcohol (PVA, Mw = 27 kDa) was purchased from Macklin (Shanghai, China). 4-Bromomethyl-phenylboric acid (BPA) and N-N-N′-N′-tetramethyl-1-3-propylenediamine (TMPA) were purchased from Aladdin (Shanghai, China). Bovine serum albumin (BSA) and 4′,6-diamidino-2-phenylindole (DAPI) were purchased from Beyotime (Shanghai, China). Hematoxylin-eosin (H&E) and Masson’s trichrome staining kits were purchased from Solarbio Science & Technology Co., Ltd. (Beijing, China). Metformin was purchased from Sigma (Shanghai, China). Fibroblast growth factor 21 (FGF21, MW = 19.4 kDa) was offered by the Key Laboratory of Biotechnology and Pharmaceutical Engineering, Wenzhou Medical University, China. All reagents used were analytic reagent (AR) grade and were used as received.

SD rats’ knee joints from each group were collected for further evaluation, after decalcification, these samples were paraffin-embedded and stained with hematoxylin-eosin (H&E) (Solarbio, China) and Safranin O-fast green (Solarbio, China). Microscopy was used to collect photographs of these stained samples, which were then evaluated histologically.

All mice were weighed before anesthesia, and the entire colons were rapidly collected. The total colon lengths and weights were measured [26 (link)], and the colon weight index (CWI), CWI = colon weight/body weight × 100%, was calculated [27 (link), 28 (link)]. Distal colon tissue was taken for pathological tissue testing. The tissues were washed with phosphate-buffered saline (PBS, pH = 7.2) and fixed in 4% paraformaldehyde for 24 h at room temperature. After paraffin embedding, 4 μm thick sections were cut to dehydrate by an ethanol gradient and stained with hematoxylin-eosin (H&E) (Solarbio, Beijing, China) for pathological histological analysis. Next, colon injury and inflammation were observed under a microscope (Leica, Wetzlar, Germany). Histological damage was assessed as a combined score of inflammatory cell infiltration (scores 0–3), mucosal damage (scores 0–3), crypt damage (scores 0–4), and regeneration (scores 0–4), using a previously described method [29 (link)].

4-week-old male Kunming mice were purchased from the Experimental Animal Center of Fourth Military Medical University and approved by the Animal Ethics Committee of Fourth Military Medical University (License number: IACUC-2020065). The animal experiment was complied with the ARRIVE guidelines and was performed in accordance with the National Institutes of Health guide for the care and use of Laboratory animals. 60% high-fat diet were purchased from Readydietech, China. Streptozocin (STZ) was purchased from Sigma, USA. Hematoxylin-Eosin (HE) was purchased from Solarbio, China. CD31 antibody was purchased from Abcam (28364, 1:100), USA. F4/80 antibody was purchased from Abcam (6640, 1:100), USA. CD16/32 antibody was purchased from BD Biosciences (553142, 1:50), USA. Fluorescence secondary antibody was purchased from Invitrogen, USA. IL-1β and TNF-α ELISA kits were purchased from Proteintech, USA.