Downregulation of interleukin 36γ and its cleaver cathepsin G following treatment with narrow-band ultraviolet B phototherapy in psoriasis vulgaris

BACKGROUND

Growing evidence suggests the important role of IL-36 in the pathogenesis of psoriasis. Cathepsin G is a neutrophil-derived protease that can activate IL-36γ.

OBJECTIVE

To assess the expression of IL-36γ and cathepsin G in psoriasis and to quantify the impact of treatment with narrow-band ultraviolet B phototherapy (NB-UVB) on their levels.

METHODS

This case-control study involved 26 patients with moderate-severe psoriasis and 25 healthy volunteers. Psoriasis patients eligible for phototherapy received 24 NB-UVB sessions. Punch skin biopsies were obtained from all participants at recruitment and after phototherapy from patients. Real-time PCR was utilized for quantitative assessment of IL-36γ and cathepsin G expression in tissue samples.

RESULTS

The expression of IL-36γ and cathepsin G was significantly higher in psoriasis before NB-UVB therapy compared to controls (p < .001). Both proteins decreased significantly with clinical improvement following NB-UVB therapy compared to baseline (p < .001). However, their expression after treatment was still higher than controls (p < .001).

CONCLUSION

IL-36γ and cathepsin G expression is upregulated in psoriatic lesions, supporting their role as mediators of inflammation in psoriasis. Downregulation of IL-36γ and cathepsin G is a possible mechanism for psoriasis improvement after NB-UVB therapy. IL-36 and cathepsin G can be considered as therapeutic targets for psoriasis.

Clinical and epidemiologic features of psoriasis patients in an Egyptian medical center

Background

Identification of epidemiologic and phenotypic variations of psoriasis among different ethnic groups can further our understanding of this perplexing disease, aiming at better management of patients worldwide.

Objective

To provide a descriptive analysis of psoriasis patients registered at Kasr Al-Ainy Psoriasis Unit Disease Registry.

Methods

This retrospective single-center registry study included patient records between November 2015 and November 2018 (2534 patients). Sociodemographic and phenotypic data were analyzed.

Results

The mean age of the registered patients was 39.3 years and 56.3% were men. Stress was the main precipitating factor (48.3%), whereas the most common symptom reported was itching (82.4%). The median body mass index was 27.5, and the median percentage of body surface area involved was 10.0. The mean Psoriasis Area Severity Index score was 8.7, and the mean Psoriasis Disability Index score was 13.0. Both parameters correlated positively, and both showed significantly higher means in smokers.

Limitations

Despite that the study was performed at a highly specialized tertiary care center with a high flow of patients, this was still a single-center registry.

Conclusions

This work shows that the characteristics of Egyptian patients with psoriasis are comparable to those of other studied ethnic groups, with minor differences.

Role of the cutaneous extraneuronal cholinergic system in the pathogenesis of psoriasis: a case-control study

BACKGROUND

Although during recent years there have been considerable advances in elucidating the mechanisms of psoriasis pathogenesis, its full understanding is still distant. A cholinergic dysfunction has been proposed in the pathophysiology of some inflammatory and autoimmune diseases, including psoriasis.

AIM

To determine tissue levels of acetylcholine (ACh) and its muscarinic and nicotinic receptors (mAChR and nAChR) in psoriasis vulgaris lesions in comparison with normal control skin.

METHODS

This case-control study included 30 patients with psoriasis vulgaris and 30 controls. A 4-mm punch skin biopsy was taken from the psoriatic plaques of patients and normal skin of controls. ACh level was measured in tissues using the colorimetric method, while mAChR and nAChR gene expression was determined by real-time PCR.

RESULTS

The level of ACh was significantly higher in patients (mean ± SD: 5.95 ± 2.69) than in controls (1.12 ± 0.34) (P < 0.001). mAChR and nAChR expressions were significantly higher in patients compared with the controls (P < 0.001). A significant positive correlation was detected between the expression of nAChR in patients and the duration of psoriasis (r = 0.46, P = 0.01), and the body mass index of the patients correlated positively with both nAChR (r = 0.40, P = 0.027) and mAChR expression (r = 0.448, P = 0.013).

CONCLUSION

Abnormalities in the cutaneous extraneuronal cholinergic system could be involved in the pathogenesis of psoriasis. The high expression of nAChRs in patients with longer disease durations might represent an attempt by the body to regulate the inflammatory cascade in psoriatic lesions. The high expression of mAChR in psoriatic lesions may provide a link between psoriasis and obesity.