Fig. 5

Hypo-ADSCs-Exo restores the contents of proteoglycans (PGs) and collagen in degenerative lumbar facet joint cartilage. (A) Synchrotron infrared imaging of lumbar facet joint showing the optical stereogram of the normal cartilage area; Scale bar, 20 μm (B) Representative infrared spectra. The absorption of the most important biomolecules is indicated. Red arrows point out the peaks of carbohydrate (1180-985 cm^-1) and amide I (1775-1590 cm^-1) which correlate with PGs and collagen respectively; (C) and (D) False-colored chemical mappings to record the distribution of PGs and collagen across cartilage area of lumbar facet joint according to their characteristic feature around 1805 cm^-1 and 1651 cm^-1 respectively. All chemical mappings were normalized to the same color scale for comparison purpose with red color representing the highest ratio and blue color the lowest ratio as shown below the figures; (E) Representative optical stereogram and chemical mappings of the collagen and PGs across cartilage area of lumbar facet joint among four groups; Optical images were captured under 32x objective lens. Scale bar, 20 μm (F-G) Quantitative analysis of PGs and collagen in (E). All data are shown as the mean ±standard deviation (SD). n=6 per group. *p ＜ 0.05, compared with PBS treated group mice, ^#p ＜ 0.05, compared with ADSCs-Exo mice