Targeting the epigenetic regulator bromodomain-containing protein 4 by BRD4 siRNA lipoplexes and PFI-1 in psoriasis

Sowjanya Thatikonda1, Venkatesh Pooladanda1, Geetanjali Devabattula1

  • 1Department of Biological Sciences (Regulatory Toxicology), National Institute of Pharmaceutical Education and Research (NIPER), Balanagar, Hyderabad, Telangana 500037, India.

PubMed

Insights

Bromodomain-containing protein 4 (BRD4) inhibition effectively treats psoriasis symptoms in mice by reducing inflammation and skin thickening. This suggests BRD4 is a promising therapeutic target for psoriasis treatment.

Area of Science:

  • Dermatology
  • Molecular Biology
  • Immunology

Background:

  • Psoriasis is a chronic inflammatory skin condition involving keratinocyte hyperproliferation and immune cell infiltration.
  • Bromodomain-containing protein 4 (BRD4), a BET family member, is linked to inflammatory disorders, but its role in psoriasis is not well understood.

Purpose of the Study:

  • To investigate the role of BRD4 in psoriasis pathogenesis.
  • To evaluate the therapeutic potential of BRD4 inhibition in experimental psoriasis.

Main Methods:

  • Utilized BRD4-specific small interfering RNA lipoplexes (BRD4-siRNA-LP) and the small molecule inhibitor PFI-1.
  • Analyzed BRD4's effects in human macrophages via gene knockout and overexpression.
  • Assessed outcomes in Imiquimod (IMQ)-induced psoriasis mouse models.

Main Results:

  • BRD4 inhibition downregulated pro-inflammatory cytokines (IL-1β, IL-6, IL-17, TGF-β, TNF-α) and key signaling proteins (p65 NF-κB, MAPKs, STAT3).
  • BRD4 suppression reduced psoriatic plaque formation and epidermal hyperplasia in mice.
  • BRD4 was found to interact with p65 NF-κB and STAT3, and inhibition disrupted these interactions.

Conclusions:

  • BRD4 plays a significant role in psoriasis pathogenesis.
  • Inhibiting BRD4 with BRD4-siRNA-LP and PFI-1 effectively alleviates experimental psoriasis.
  • BRD4 represents a promising therapeutic target for psoriasis treatment.