MMP9 and acute kidney injury: Also, aside from acute kidney injury (AKI) [17], the association of MMP-9 and TIMP-1 with the clinical manifestations of sepsis-associated organ dysfunction has not yet been investigated despite numerous animal models of sepsis that clearly demonstrate elevated expression of these biomarkers in the kidney [18], lung [18–21], liver [18, 21], brain [22], heart [23], and endothelium [24].