Research Paper Volume 9, Issue 6 pp 1607—1622

Figure 2. Biochemical analyses of CS-GAG sulfation. 12-, 18-month old brains shows an increase in the ratio C4S/C6S in the PNNs fraction. (A) Measurement of the total CS GAGs quantity in the various fractions extracted from brains at time points from 3 to 18 months. There is no overall change in GAGs quantity with time. (B) The structure of the repeating disaccharide making up CS GAGs. The left diagram is sulfated in the 4 position (C4S), the right in the 6 position (C6S). (C) A composite image representing examples of FACE gels with CS GAGs extracted from the diffuse (B1) ECM at 3,6, 12 and 18 months. The GAGs were digested into disaccharides using chABC and the resulting disaccharides were electrophoresed in the FACE gel. The C4S disaccharides were identified by comparing the band location to the standard disaccharides in the first and last lanes. (D) Quantification of the FACE gels from the lower part of the sulfated band. C4S remains stable over time. (E) A composite image representing examples of FACE gels of CS GAGs extracted from the PNNs (B4) fraction at 3,6, 12 and 18 months. (F) There is a non-significant trend of an increase in C4S over time.

Graphs show mean ± s.e.m. *** indicates a significant relationship between the considered CS GAGs and time by One Way Anova, p >0.001.** indicates a significant relationship between the considered ratio and time by Kruskal-Wallis test, p =0.002.B1, ECM fraction; B4, PNNs fraction; B1+B2+B3+B4, sum of GAGs from the four fractions of each brain; 3m, 3-month-old brains; 6m, 6-month-old brains; 12m, 12-month-old brains; 18m, 18-month-old brains; C4S, Chondroitin-4-sulfate; C6S, Chondroitin-6-sulfate; C0S, Chondroitin non-sulfated; HA, hyaluronic acid.