Fig. 5

a Inhibition of gelatinolytic activity by A. arborescens and A. vera extracts. Extracellular HT29 cell media samples were subjected to a non-reducing gel electrophoresis (SDS-PAGE) in 12,5% /w/v) polyacrylamide gels supplemented with 0.2% (w/v) gelatin from bovine skin, type B. After renaturation, MMP-2 and MMP-9 activity was stimulated by incubation in reaction buffer (see material and methods) and the gel was stained for total protein. The presence of gelatinase activities was observed by clear bands against a dark blue background. b Relative activities of MMP-9 and MMP-2 bands calculated as a % of controls. c Gelatinolytic activities of commercial MMP-9 after exposure to Aloe methanolic extracts. MMP-9 was incubated in the presence of A. arborescens or A. vera extracts and its activity was quantified by the DQ-gelatin assay. Results are expressed as percentage of controls. Values are the mean of at least three replicate experiments ± SD. *p < 0.05, **p < 0.001