3.3 Plasma syndecan-1 and tryptase concentrations increase
during acute symptomatic crises
We next evaluated potential differences between plasma SD-1 and tryptase
concentrations during the acute phase of CAS and those in control
subjects, in order to determine whether endothelial glycocalyx shedding
was activated, and whether mast cell activation might play a role in
this process. During acute exacerbations, SD-1 plasma concentrations
were four-fold higher (p < 0.0001) than those in control
subjects, and also substantially higher than those seen in the same
patients during clinically quiescent periods (p < 0.0001)
(Fig. 3A) .
In view of previous evidence linking activation of mast cells with CAS
(Forman et al. , 1985;
Kounis et al. , 1991), we measured
tryptase concentrations in plasma samples from the same patients during
chronic and acute phases of CAS. There was a small but consistent
increase in plasma tryptase concentrations during acute phases (n = 10;
p = 0.03, Fig. 3B ).
However, plasma concentrations of MDA, an index of systemic oxidative
stress, did not vary significantly between control subjects (n = 9; 3.05
± 0.06 µM) and patients during either chronic (3.24 ± 0.15µM) or acute
(3.09 ± 0.15 µM) phases of CAS (n = 9 for each phase).