3.4 Degradation of endothelial glycocalyx potentially activated
oxidative stress injuries in HPMEC
TNF-α and IL-6 were the classical pro-inflammation cytokines to
accessing inflammatory activities and prognostic outcomes. We,
therefore, evaluated the expression of TNF-α and IL-6 in treated cells.
Our results found that heat stress and LPS significantly increased the
production of TNF-α and IL-6 in HS, HPSE, and UFH groups, compared with
the CON group (P < 0.05) (Figure 4A ). This
upregulation was more pronounced in cells treated with HPSE but more
modest in those treated with UFH in comparison with those treated with
heat stress and LPS alone (P < 0.05) (Figure
4A ). These results indicated that heat stress and LPS promoted
inflammatory activities of HPMEC by an endothelial glycocalyx degraded
mechanism.
Our previous study demonstrated that generation of ROS was the critical
mediator in heat stress-induced apoptosis, 27 which
was also known to be a classical marker related to oxidative stress in
the tissue. We, thus, detected the changes of ROS level in HPMEC by
DCFH-DA marked with green fluorescence, which produces enhanced
fluorescence when cells generate ROS. Heat stress and LPS significantly
increased the intracellular ROS levels in HPMEC in comparison with the
CON group (Figure 4B ) (P < 0.05). In addition,
the ROS level was significantly higher in HPSE treated-cells but was
lower in UFH treated-cells than HS+LPS-treated cells (P< 0.05) (Figure 4B ). These results suggested that
oxidative stress of HPMEC as a result of damaged endothelial glycocalyx
induced by heat stroke.