Journal: International Journal of Molecular Sciences
Article Title: Cilastatin Attenuates Acute Kidney Injury and Reduces Mortality in a Rat Model of Sepsis
doi: 10.3390/ijms26167927
Figure Lengend Snippet: Summary image of the effects of cilastatin on the Toll-like receptor 4 (TLR4)/Myeloid differentiation factor 88 (MyD88)/Nuclear Factor-κB/NF-κB) pathway and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome in cecal ligation and puncture (CLP)-induced inflammation and acute kidney injury. The TLR4 signaling complex is organized and localized in the cholesterol lipid rafts on the brush border apical side of renal proximal tubular epithelial cells, geographically close to the renal dehydrodipeptidase I (DHP-I) enzyme. In the left panel, with cholesterol rafts intact, damage-associated molecular patterns (DAMPS) or pathogen-associated molecular patterns (PAMPS), such as bacterial lipopolysaccharide (LPS), activate the TLR4/MyD 88 pathway, leading to the activation of NF-κB and pro-inflammatory cytokine and chemokine production. NF-κB is also involved in the activation of the NLRP3 inflammasome that leads to the activation of caspase-1, which, in turn, regulates the processing of inflammatory pro-cytokines to active cytokines (such as interleukin (IL)-1β), amplifying inflammatory damage and cell death, which exacerbates kidney injury. In the right panel, cilastatin binding to the membrane DHP-I in cholesterol lipid rafts causes modifications in the rafts, preventing the correct assembly and activation of the TLR4 complex and reducing the activation of NF-κB and the NLRP3 inflammasome. Thus, the renal cell is protected. K+, potassium; Ca2+, calcium; TIRAP, TIR Domain Containing Adaptor, Protein; IκB, inhibitor of nuclear factor kappa B; TNFα, tumor necrosis factor alpha; GSDMD, Gasdermin D.
Article Snippet: Sections were then incubated overnight at 4 °C in a humidified chamber with primary antibodies diluted in PBS-T, 4% bovine serum albumin, and 1% host serum in which the secondary antibody was obtained as follows: mouse anti-RelA/NF-κB p65 monoclonal antibody (Novus Biologicals, Minneapolis, MN, USA [dilution 1:100], ref. NB100-56712); mouse anti-TLR4 (25) monoclonal antibody (Santa Cruz Biotechnology [dilution 1:50], ref. sc-293072); and rabbit anti-MyD88 polyclonal antibody (Novus Biologicals [dilution 1:50], ref. NB100-56698).
Techniques: Binding Assay, Ligation, Activation Assay, Membrane