Research Paper Volume 11, Issue 23 pp 11391—11415

Melatonin protects blood-brain barrier integrity and permeability by inhibiting matrix metalloproteinase-9 via the NOTCH3/NF-κB pathway

Figure 2. Melatonin inhibited NOTCH3 and MMP-9 but not MMP-2 gene expression, and increased TIMP-1 but not TIMP-2 gene expression in different culture conditions. Pericytes cultured in the Transwells were pretreated with IL-1β (10 ng/mL) for 24 h in serum-free medium with or without additional pretreatment with DAPT (10 μmol/L), PDTC (25 μmol/L), or WB-3CT (20 μmol/L), and in combination with melatonin (MEL, 10 μmol/L) for 30 min. (AE) NOTCH3, MMP-2, MMP-9, TIMP-1, TIMP-2 gene expression levels were quantified in IL-1β-treated, IL-1β + DAPT, and IL-1β + DAPT + MEL groups compared with the control group. qRT-PCR data were normalized to GAPDH expression. (FJ) NOTCH3, MMP-2, MMP-9, TIMP-1, TIMP-2 gene expression levels were quantified in IL-1β-treated, IL-1β + PDTC and IL-1β + PDTC + MEL groups compared with the control group. (KO) NOTCH3, MMP-2, MMP-9, TIMP-1, TIMP-2 gene expression levels were quantified in IL-1β-treated, IL-1β + SB-3CT and IL-1β + SB-3CT + MEL groups compared with the control group. (P) The ratio of MMP9/TIMP1 relative transcript levels. Results are presented as the mean ± SD, n = 3. *p < 0.01 compared with the control; #p < 0.01 compared with the IL-1β-treated group; ##p < 0.01 compared with the IL-1β + DAPT group; $p < 0.01 compared with the IL-1β + PDTC group; &p < 0.01 compared with the IL-1β + SB-3CT group.