MMP9 and Sepsis: During sepsis, matrix metalloproteinase-9 (MMP-9) and hyaluronidase (HYAL1) activity upregulates, directly cleaving the glycocalyx (Xing et al., 2023; Lin et al., 2024); TNF-α and IL-1β inhibit glycocalyx synthase (e.g., EXTL3) via the TLR4/NF-κB pathway (Lei et al., 2021; Marques et al., 2022).