Inhibition of keratinocyte necroptosis mediated by RIPK1/RIPK3/MLKL provides a protective effect against psoriatic inflammation

Cell Death Dis. 2020 Feb 19;11(2):134. doi: 10.1038/s41419-020-2328-0.

Abstract

Psoriasis is a common autoimmune and chronic inflammatory skin disorder globally affecting 0.51-11.43% of adults. Inflammation-associated cell death in keratinocytes plays a key role in the process of integrate inflammatory cascade in psoriasis. Necroptosis is a regulated necrotic cell death mediated by receptor interacting protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like pseudokinase (MLKL), which participates in many human inflammatory diseases. However, the mechanism and function of programmed necrosis in psoriasis is not well-illustrated. In the current study, we provide evidence for the involvement of necroptosis in psoriasis. RIPK1 and MLKL were significantly upregulated and localized in all layers of the epidermis in human psoriatic lesions, while RIPK3 and phosphorylated MLKL were mainly expressed in keratinocytes, which located in the upper layers. Increased tendency of necroptosis was also found in IMQ-induced psoriasiform skin of mice. Further, we discovered that both the inhibitor of RIPK1 R-7-Cl-O-Necrostatin-1 (Nec-1s) and MLKL-inhibitor necrosulfonamide (NSA) suppressed necroptosis in HaCaT cells and IMQ mouse models, powerfully blocked IMQ-induced inflammatory responses in vivo, and significantly downregulated the production of inflammatory factors like IL-1β, IL-6, IL-17A, IL-23a, CXCL1, and CCL20. These findings promote the development of new therapies for the treatment of necroptosis-activated pathologies for psoriasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acrylamides / pharmacology
  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Cytokines / metabolism
  • Disease Models, Animal
  • Female
  • HaCaT Cells
  • Humans
  • Imidazoles / pharmacology
  • Imiquimod
  • Indoles / pharmacology
  • Inflammation Mediators / metabolism
  • Keratinocytes / drug effects*
  • Keratinocytes / enzymology
  • Keratinocytes / pathology
  • Mice, Inbred BALB C
  • Necroptosis / drug effects*
  • Phosphorylation
  • Protein Kinase Inhibitors / pharmacology*
  • Protein Kinases / metabolism*
  • Psoriasis / chemically induced
  • Psoriasis / enzymology
  • Psoriasis / pathology
  • Psoriasis / prevention & control*
  • Receptor-Interacting Protein Serine-Threonine Kinases / antagonists & inhibitors*
  • Receptor-Interacting Protein Serine-Threonine Kinases / metabolism
  • Signal Transduction
  • Skin / drug effects*
  • Skin / enzymology
  • Skin / pathology
  • Sulfonamides / pharmacology

Substances

  • Acrylamides
  • Anti-Inflammatory Agents
  • Cytokines
  • Imidazoles
  • Indoles
  • Inflammation Mediators
  • N-(4-(N-(3-methoxypyrazin-2-yl)sulfamoyl)phenyl)-3-(5-nitrothiophene-2-yl)acrylamide
  • Protein Kinase Inhibitors
  • Sulfonamides
  • necrostatin-1
  • MLKL protein, human
  • MLKL protein, mouse
  • Protein Kinases
  • RIPK1 protein, human
  • RIPK3 protein, human
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • Ripk1 protein, mouse
  • Ripk3 protein, mouse
  • Imiquimod