Journal: Journal of Neuroinflammation
Article Title: Inhibition of mast cell tryptase attenuates neuroinflammation via PAR-2/p38/NFκB pathway following asphyxial cardiac arrest in rats
doi: 10.1186/s12974-020-01808-2
Figure Lengend Snippet: PAR-2 activation reversed the anti-neuroinflammatory effects of APC366 at 24 h after ACA. Representative western blot images and quantitative analysis of MC-tryptase ( a ), PAR-2 ( b ), p38 ( c ), p-p38 ( d ), NFκB ( e ), and proinflammatory cytokines ( f , g ) in the brain at 24 h following ACA. The levels of the pathway proteins were markedly increased following ACA. The inhibition of MC-tryptase significantly reduced PAR-2, p-p38 and NFκB, TNF-α, and IL-6 levels in rats treated with APC366 compared to the ACA + vehicle group. Further activation of PAR-2 by AC55541 caused higher expressions of p-p38, NFκB, and proinflammatory cytokines compared to the vehicle-treated ACA group. The co-administration of APC366 and AC55541 not only abolished the protective effect of APC366 in ACA rats, but also offset the detrimental effects of pharmacological activation of PAR-2 by AC55541, resulting in significantly lower levels of p-p38, NFkB, IL-6, and TNF-a compared to AC55541 alone. Selective p38 inhibitor, SB203580 reversed the aggravated neuroinflammation due to AC55541 by decreasing the expressions of p-p38, NFκB, IL-6, and TNF-α. h Neurologic deficit score at 24 h following ACA. The inhibition of MC-tryptase significantly improved neurologic function. This effect was reversed with the activation of PAR-2 by AC55541 at 24 h following ACA. The activation of PAR-2 by AC55541 alone significantly worsened neurological performance; however, this effect was rescued by the p-38 inhibitor, SB203580, compared to the ACA + vehicle group. Data are expressed as mean ± SD. n = 6/group. ANOVA, Tukey. ** p < 0.001 compared to sham, * p < 0.05 compared to sham, && p < 0.001 compared to ACA + vehicle, & p < 0.05 compared to ACA + vehicle, $ p < 0.05 compared to ACA + APC366 (50 μg), % p < 0.05 compared to ACA + APC366 (50 μg) + AC55541 (30 μg), # p < 0.001 compared to ACA + AC55541 (30 μg), ## p < 0.05 compared to ACA + AC55541 (30 μg)
Article Snippet: AC55541 (selective PAR-2 activator; 30 μg/rat) and SB203580 (selective p38 inhibitor; 300 μg/rat; Santa Cruz Biotechnology, Dallas, TX, USA) were used for intervention.
Techniques: Activation Assay, Western Blot, Inhibition