Enhanced Inflammasome Activity in Patients with Psoriasis Promotes Systemic Inflammation

Purinergic Signaling and Inflammasome Activation in Psoriasis Pathogenesis

Psoriasis is a chronic inflammatory disease of the skin associated with systemic and joint manifestations and accompanied by comorbidities, such as metabolic syndrome and increased risk of cardiovascular disease. Psoriasis has a strong genetic basis, but exacerbation requires additional signals that are still largely unknown. The clinical manifestations involve the interplay between dendritic and T cells in the dermis to generate a self-sustaining inflammatory loop around the TNFα/IL-23/IL-17 axis that forms the psoriatic plaque. In addition, in recent years, a critical role of keratinocytes in establishing the interplay that leads to psoriatic plaques’ formation has re-emerged. In this review, we analyze the most recent evidence of the role of keratinocytes and danger associates molecular patterns, such as extracellular ATP in the generation of psoriatic skin lesions. Particular attention will be given to purinergic signaling in inflammasome activation and in the initiation of psoriasis. In this phase, keratinocytes’ inflammasome may trigger early inflammatory pathways involving IL-1β production, to elicit the subsequent cascade of events that leads to dendritic and T cell activation. Since psoriasis is likely triggered by skin-damaging events and trauma, we can envisage that intracellular ATP, released by damaged cells, may play a role in triggering the inflammatory response underlying the pathogenesis of the disease by activating the inflammasome. Therefore, purinergic signaling in the skin could represent a new and early step of psoriasis; thus, opening the possibility to target single molecular actors of the purinome to develop new psoriasis treatments.

Evaluation of NLRP3 (rs10754558) and PTPN22 (1858C/T) (rs2476601) Functional Polymorphisms in Psoriasis Susceptibility in Egypt

BACKGROUND

Psoriasis is a complex autoimmune multifactorial disease induced by interaction of environmental and genetic factors. This research aimed to clarify the association of NLRP3 (rs10754558) and PTPN22 (1858C/T) (rs2476601) polymorphisms with susceptibility to psoriasis.

METHODS

This case-control study involved 150 patients diagnosed with psoriasis and 100 age- and gender-matched apparently healthy individuals. NLRP3 (rs10754558) polymorphism was done by real time PCR and PTPN22 1858C/T (rs2476601) genotype was identified by tetra-primer amplification refractory mutation system-polymerase chain reaction (PCR) method.

RESULTS

The genotypes distribution of NLRP3 (rs10754558) were significantly associated with psoriasis (p<0.0001). Whereas for PTPN22 (1858C/T) (rs2476601), no significance was found (p=0.09). NLRP3 (rs10754558) GC genotype revealed a significant association with psoriasis (p<0.0001), mainly among male (p=0.004) patients with mild psoriasis (p=0.001) and affected extremities (p=0.0001).

CONCLUSION

We can conclude that the NLRP3 (rs10754558) GC genotype may play a role in psoriasis susceptibility among male Egyptian populations with affected extremities. Future studies must evaluate its role in the prevention or the treatment of psoriasis.

The Psoriatic Nonlesional Skin: A Battlefield between Susceptibility and Protective Factors

In the last two decades, large-scale gene-expression studies on psoriatic skin samples revealed that even though nonlesional skin is macroscopically identical to healthy skin, it harbors several molecular differences. Originally, these molecular differences were thought to represent susceptibility factors for plaque formation. However, we review in this paper the several factors of immune regulation and structural alteration that are specific for the nonlesional skin and serve as protective factors by counteracting plaque formation and contributing to the maintenance of the nonlesional phenotype.

Cardiovascular Risk in Patients With Psoriasis: JACC Review Topic of the Week

Psoriasis is a chronic inflammatory skin disease that affects 2% to 3% of the U.S. population. The immune response in psoriasis includes enhanced activation of T cells and myeloid cells, platelet activation, and up-regulation of interferons, tumor necrosis factor-α, and interleukins (ILs) IL-23, IL-17, and IL-6, which are linked to vascular inflammation and atherosclerosis development. Patients with psoriasis are up to 50% more likely to develop cardiovascular disease (CV) disease, and this CV risk increases with skin severity. Major society guidelines now advocate incorporating a psoriasis diagnosis into CV risk prediction and prevention strategies. Although registry data suggest treatment targeting psoriasis skin disease reduces vascular inflammation and coronary plaque burden, and may reduce CV risk, randomized placebo-controlled trials are inconclusive to date. Further studies are required to define traditional CV risk factor goals, the optimal role of lipid-lowering and antiplatelet therapy, and targeted psoriasis therapies on CV risk.

Killing Two Birds with One Stone: TNF Antagonists Downregulate Systemic IL-1β in Psoriasis

Verma et al. (2021) demonstrate that TNF antagonists unexpectedly downregulate systemic IL-1β by inhibiting noncanonical inflammasome activation in patients with psoriasis. Given the known involvement of IL-1β in the pathogenesis of psoriasis skin manifestations and associated comorbidities, the findings of Verma et al. (2021) highlight a potential added benefit of targeting TNF in psoriasis.

The interleukin-1 family cytokines in psoriasis: pathogenetic role and therapeutic perspectives

Introduction: IL-1 family cytokines play an important role in the innate immune system and their uncontrolled activation and expression can initiate a pathologic inflammatory response. Their role in psoriasis, pustular psoriasis, and psoriatic arthritis has been studied, and they offer potential interest as therapeutic targets.Areas covered: This review focuses on the role that interleukin (IL)-1 family cytokines play in psoriasis pathogenesis, with a special focus on pustular psoriasis, and how these cytokines can be used as therapeutic targets. Using PubMed, we review the literature for articles related to IL-1 family cytokines and psoriasis, focusing on pustular psoriasis, and including pathogenesis, genetics and therapeutic targets.Expert opinion: IL-1 and IL-36 cytokines act as critical drivers of the autoinflammatory responses involved in pustular psoriasis. Studies on the specific role of each IL-1 cytokine are needed, as well as of their regulatory pathways. Targeting of IL-1 family cytokines has been used in pustular psoriasis, with IL-1 and IL-36 R blockade showing promising results.