Journal: Bone & Joint Research
Article Title: High-intensity running exercise promotes knee meniscal damage via the PI3K/AKT/mTOR axis
doi: 10.1302/2046-3758.1411.BJR-2024-0535.R1
Figure Lengend Snippet: Excessive mechanical stress promotes meniscus degeneration.a) Immunohistochemical staining revealed the expression of Aggrecan and matrix metalloproteinase 13 (MMP13) in the anterior horn, posterior horn, and articular surface of the meniscus following treadmill intervention in mice. Scale bar: 100 µm. (The same group showed serial sections from the same mouse knee joint tissue for staining analysis.) b) Statistical analysis of the differences in MMP13 and Aggrecan expression between the anterior and posterior horns of the meniscus and the articular cartilage surface groups (n = 5/group). Data were analyzed using one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test. c) Immunofluorescence displaying COL1-positive, Aggrecan-positive, MMP13-positive, and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5)-positive cells as a proportion of total meniscal cells in primary medial meniscal cells (n = 3/group). Data are presented as the mean (SD). Scale bar: 200 µm. d) Quantification of the positive meniscus cells (P-PI3K, P-AKT, and P-S6) as a proportion of total meniscal cells (n = 3/group). Data were analyzed using independent-samples t -test. *p < 0.05, **p < 0.01, ***p < 0.001. ns, non-significant.
Article Snippet: Mouse anti-glyceraldehyde 3-phosphate dehydrogenase (GAPDH) (1:10,000, ab8245; Abcam, UK), rabbit anti-MMP13 (1:2,000, 18165-1-AP; Proteintech, USA), rabbit anti-A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) (1:1,000, A2836; Abclonal, USA), rabbit anti-collagen type I (COL1) (1:2,000, 14695-1-AP; Proteintech), rabbit anti-Aggrecan (1:1,000, A11691; Abclonal), rabbit anti-phospho-PI3K p85 (1:1,000, YP0224; ImmunoWay, USA), rabbit anti-phospho-AKT (Thr308) (1:500, PC2720; Abmart, China), rabbit anti-phospho-S6 (S240/S244) (1:500, AP0537; Abclonal), rabbit anti-PI3K (1:500, A17433; Abclonal), rabbit anti-AKT (1:1,000, ab192623; Abcam), and rabbit anti-S6 (1:500, A6058; Abclonal) served as the primary antibodies used.
Techniques: Immunohistochemical staining, Staining, Expressing, Immunofluorescence
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