Immunopathogenesis of psoriasis

The therapeutic effect of glycyrrhizic acid compound ointment on imiquimod-induced psoriasis-like disease in mice

Glycyrrhetinic acid, a drug with anti-inflammatory effects, enhanced the activity of antipsoriatic efficacy. In this research, an ointment with glycyrrhetinic acid was prepaired as the major component and several other herbal monomers (astilbin, osthole, and momordin Ic) have antipsoriatic activity as minor components. Then an Imiquimod-induced psoriasis-like mouse model was established and the damaged skin condition of the administered group, the changes in the spleen index and the secretion of inflammatory factors in mouse skin were observed. Calcipotriol ointment was used as a positive control to compare the efficacy. Glycyrrhizic acid compound ointment significantly improved imiquimod-induced psoriasis in mice and reduced the secretion of TNF-α, IL-12, IL-17, and IL-23 in mouse skin, and showed a stronger therapeutic effect than calcipotriol ointment. Calcipotriol ointment did not significantly alleviate imiquimod-induced splenomegaly and did not significantly reduce the expression of IL-17 and IL-23 in mouse skin. Glycyrrhetinic acid compound ointment was more effective than calcipotriol and was dose-dependent in the treatment of imiquimod-induced psoriatic dermatitis in mice. Meanwhile,calcipotriol was not suitable for the treatment of Imiquimod -induced psoriasis-like mice.

Investigation of the relationship between atopy and psoriasis

Introduction

The relationship between allergic and autoimmune diseases is an important issue, which has recently attracted the researchers’ interest.

Aim

To determine the relationship between atopy and psoriasis.

Material and methods

This case-control study was conducted on 102 patients referred to the Ghaem Hospital, Mashhad, Iran, in 2016. The participants were assigned into two groups: experimental and control groups, including the patients suffering from psoriasis and those with no history of cutaneous or other systemic diseases, respectively. Both groups filled in the ISAAC questionnaire and had skin prick tests. In addition, the serum levels of immunoglobulin E (IgE) and blood eosinophil cell count were measured. The data were analysed using the regression test through SPSS version 16.

Results

According to the results of the ISAAC questionnaire, there was a significant difference between the control and experimental groups in terms of asthma (p = 0.04). The mean serum concentrations of IgE and eosinophil cell count were not significantly different between the experimental (153.93 IU/ml and 187.77 cells/μl, respectively) and control groups (152.19 IU/ml and 187.68 cells/μl, respectively) (p = 0.057 and p = 0.886, respectively). In addition, there was an indirect correlation between the eosinophil cell count and psoriasis severity (p = 0.032, r = –0.297). Furthermore, the comparison of the skin prick test results revealed no significant difference between the two groups regarding the number of positive and negative cases (p = 0.436).

Conclusions

The findings suggested that atopy was not common in the patients with psoriasis and supported the concept that atopy protects against such autoimmune diseases such as psoriasis.

Increased βTrCP are associated with imiquimod-induced psoriasis-like skin inflammation in mice via NF-κB signaling pathway

Psoriasis is a common inflammatory skin disease characterized by T cell-mediated hyperproliferation of keratinocytes, increased angiogenesis and inflammation. Accumulating evidence suggests that some keratinocyte differentiation events are controlled by the ubiquitin/proteasome system. β-transducin repeat-containing protein (βTrCP) serve as substrate recognition component of E3 ubiquitin ligases that control stability of important regulators of signal transduction including the nuclear factor (NF)-κB signaling, a key regulatory element in inflammatory pathways related to psoriasis, suggesting a potential role of βTrCP in psoriasis pathogenesis. However, no published study has investigated the role of βTrCP in the etiology of psoriasis. Here, we combined an in vitro cell model of tumor necrosis factor (TNF)-α-induced keratinocyte inflammation and an animal model of imiquimod (IMQ)-induced psoriasis-like inflammation to investigate the pathogenic mechanisms in psoriasis-like dermatitis and assess its βTrCP/NF-κB dependency. Daily application of IMQ on mouse back skin induced inflamed scaly skin lesions resembling plaque type psoriasis. These lesions were associated with elevated βTrCP levels, reduced inhibitor κB (IκB), and enhanced NF-κB activation in epidermal tissues. Furthermore, βTrCP knockdown via siRNA in in TNF-α-stimulated HaCaT and normal human epidermal keratinocytes (NHEK) cells significantly inhibited the over-activation of NF-κB and expression of intercellular adhesion molecule 1 (ICAM-1), demonstrating a pivotal role of βTrCP in regulation the TNF-α-activated NF-κB inflammatory pathways. Moreover, downregulation of βTrCP through lentiviral shRNA ameliorates IMQ-induced psoriasis-like skin lesions in vivo. In conclusion, βTrCP is involved in the NF-κB signaling mediated-, psoriasis-related inflammation and represent a novel target for developing agents to treat psoriasis.

Hepatitis C may enhance key amplifiers of psoriasis

BACKGROUND

Multiple studies have noted an association between hepatitis C and psoriasis, but it is not known whether psoriasis is a result of treatment modalities for hepatitis C or a result of hepatitis C alone.

OBJECTIVE

To examine the relationship between psoriasis and hepatitis C by measuring the expression of cathelicidin, TLR9 and IFNγ in psoriatic lesional and non-lesional skin in HCV-positive and negative psoriatic patients.

METHODS

Two 2 mm punch biopsies of lesional and non-lesional skin in 10 patients who were HCV-negative psoriatics and seven HCV-positive psoriatics were used to measure cathelicidin, TLR9 and IFNγ mRNA expression by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR).

RESULTS

The mRNA levels of cathelicidin, TLR9 and IFNγ were significantly higher in both non-lesional and lesional skin of HCV-positive patients with psoriasis as compared to HCV-negative psoriatic patients. Additionally, the IFNγ level in lesional skin of HCV-positive psoriatic patients was higher than the IFNγ level seen in non-lesional skin of those same patients.

CONCLUSION

These findings suggest that HCV infection upregulates these inflammatory cytokines, possibly increasing susceptibility to developing psoriasis.

Assessment of in vitro antipsoriatic activity of selected Indian medicinal plants

CONTEXT

Phyllanthus simplex Retz. (Phyllanthaceae), Crotolaria juncea Linn. (Leguminosae), Leucas aspera Linn. (Lamiaceae), and Vitex glabrata R.Br. (Verbenaceae) are well-known Indian medicinal plants. Different parts of these plants are used for healing purposes traditionally in the treatment of psoriasis and various other disorders. This prompted us to assess the antipsoriatic activities of these plants.

OBJECTIVES

Petroleum ether and ethanol extracts of the selected plants, i.e., P. simplex (whole plant), C. juncea (seeds), L. aspera (aerial parts), and V. glabrata (leaves) were investigated for their in vitro antipsoriatic activity.

MATERIALS AND METHODS

Antipsoriatic activity of the extracts was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, using HaCaT cells. About 200 µl of different concentrations (25, 50, 100, 200, and 400 µg/ml) of test samples were prepared in the cell culture medium and incubated for 24 h before MTT assay to determine the viable cells. The effect of these extracts on nitric oxide (NO) production and lipid peroxidation was also evaluated.

RESULTS

Our findings revealed that these plants showed promising skin keratinocyte antiproliferative activity. However, the petroleum ether extract of C. juncea (CJPE) and ethanol extract of L. aspera (LAEE) were found to exhibit significant activity (IC50 value = 45.45 and 55.36 µg/ml, respectively).

DISCUSSION AND CONCLUSIONS

The inhibitory action against NO production and lipid peroxidation in HaCaT cells suggested that the antipsoriatic activity of the extracts was mediated by an antioxidant mechanism. These findings validate the claims of the use of these plants in the treatment of psoriasis.

Compliance with pregnancy prevention plan recommendations in 8672 French women of childbearing potential exposed to acitretin

PURPOSE

Acitretin is an oral synthetic aromatic analogue of retinoic acid available in most European countries since 1988. It is mainly used to treat severe psoriasis. Like all systemic retinoids, acitretin is teratogenic. Strict pregnancy prevention is required in women of childbearing potential who use acitretin. This study assessed compliance with Pregnancy Prevention Plan (PPP) recommendations, specifically looking at compliance with pregnancy testing (PT) and pregnancy occurrence.

METHODS

A cohort of 8672 women aged 15-49 years initiating acitretin treatment from 1 January 2007 through 31 December 2013 was identified using French SNIIRAM (administrative claims data) and PMSI (hospitalisations data) databases. Pregnancy tests (PTs) were identified from reimbursed serum βHCG and urine laboratory PTs. To satisfy PT criteria, patients who started treatment had to undergo a PT within 3 days before acitretin was dispensed. Pregnancies were identified by a pregnancy-related hospital stay or an outpatient medical abortion.

RESULTS

A PT was performed in only 12% of women starting treatment and was rarely performed during treatment or during the 24 months following discontinuation of treatment. Compliance with PPP recommendations although poor appeared to be better among private dermatologists, as a PT was performed for 16% of treatment initiations (vs. 4% for general practitioners, p < 0.001). Moreover, 470 pregnancies were reported corresponding to 27 pregnancies per 1000 person-years at risk of teratogenicity.

CONCLUSIONS

This study highlights poor compliance with acitretin PPP recommendations in France. Physicians and pharmacists must more rigorously apply the acitretin PPP recommendations, and patients must be better informed about acitretin's risk of teratogenicity.

CD26/dipeptidyl-peptidase IV and adenosine deaminase serum levels in psoriatic patients treated with cyclosporine, etanercept, and psoralen plus ultraviolet A phototherapy

OBJECTIVE

The aim of this study is to determine serum levels of soluble forms of CD26/dipeptidyl-peptidase IV (DPP-IV) and adenosine deaminase (ADA), thought to be markers of T-cell activation, and changes in their levels in response to cyclosporine, etanercept, and psoralen plus ultraviolet A (PUVA) treatments with respect to disease activity.

METHODS

This study is designed as a prospective clinical study with a control group and three months of follow-up. The study included 41 patients with psoriasis and 41 healthy controls that were older than 18years of age. There were three different treatment groups: PUVA (n=15), cyclosporine (n=15), and etanercept (n=11). To determine disease severity of patients with psoriasis, psoriasis area and severity index (PASI) scores were calculated.

RESULTS

Only mean serum ADA levels were different between patients with psoriasis [mean1±standard deviation (SD)=13.9±3.3U/ml] and control group (mean±SD=12±3.5U/ml). Mean serum ADA levels were significantly higher before treatment than after treatment (mean±SD=12.4±3.4U/ml). Contrarily, following three months of therapy, mean serum CD26 levels increased significantly from 777.7±214.6 to 835.3±203ng/ml (P<0.05) and mean serum DPP-IV activity increased significantly from 12.1±4 to 15.9±4.2nmol/min (P<0.05). There was no correlation between ADA and CD 26/DPP-IV with PASI values.

CONCLUSIONS

 The results show that ADA might be a useful marker indicating disease activity and T-cell activation. As significant changes were observed in serum CD26/DPP-IV before and after treatment, we think CD26/DPP-IV might play a role in psoriasis pathogenesis, which should be clarified by further studies.

High-scatter T cells: a reliable biomarker for malignant T cells in cutaneous T-cell lymphoma

In early-stage cutaneous T-cell lymphoma (CTCL), malignant T cells are confined to skin and are difficult to isolate and discriminate from benign reactive cells. We found that T cells from CTCL skin lesions contained a population of large, high-scatter, activated skin homing T cells not observed in other inflammatory skin diseases. High-scatter T (T(HS)) cells were CD4(+) in CD4(+) mycosis fungoides (MF), CD8(+) in CD8(+) MF, and contained only clonal T cells in patients with identifiable malignant Vβ clones. T(HS) cells were present in the blood of patients with leukemic CTCL, absent in patients without blood involvement, and contained only clonal malignant T cells. The presence of clonal T(HS) cells correlated with skin disease in patients followed longitudinally. Clonal T(HS) cells underwent apoptosis in patients clearing on extracorporeal photopheresis but persisted in nonresponsive patients. Benign clonal T-cell proliferations mapped to the normal low-scatter T-cell population. Thus, the malignant T cells in both MF and leukemic CTCL can be conclusively identified by a unique scatter profile. This observation will allow selective study of malignant T cells, can be used to discriminate patients with MF from patients with other inflammatory skin diseases, to detect peripheral blood involvement, and to monitor responses to therapy.

Immunomorphology and Morphogenesis of Affected Skin Foci at Psoriasis

The article provides information about the pathogenic role of different immunocompetent cells in forming an immune inflammation in the skin of psoriasis patients, which is one of the most important factors in the development of psoriatic eruptions in case of exacerbation of the disease. The contents of CD4+ helper lymphocytes, CD8+ suppressor/cytotoxic lymphocytes, CD1a+ Langerhans cells and HLA-DR+ cells in the affected skin in psoriasis patients were analyzed. It was revealed that the development of an immune inflammation in the skin of psoriasis patients involves cells of congenital (CD1a+ Langerhans cells) and adaptive immunity (CD4+ and CD8+ Т lymphocytes), and their number grows.

Patented small molecules against psoriasis

BACKGROUND

It is hypothesized that psoriasis is an autoimmune disease. The most recent therapeutic approach that proved to be more effective than earlier methods of treatment is the use of mAb/fusion proteins. Efforts nowadays are focused on investigating the antipsoriatic affect of small molecules that can be administered orally, some of which are capable of entering cells, and being selective in targeting intracellular pathways.

OBJECTIVE

Preclinical patented small molecules that are recommended for the treatment of psoriasis are reviewed. Emphasis is placed on their mechanism of action.

METHODS

http://ep.espacenet.com/ , Pubmed, Scopus and Google websites were the main sources used for the patented small molecule search. A number of patents were poorly described and difficulties were faced in trying to figure out the patentee(s) explanation. Moreover, most patents were recommended for the treatment of a number of autoimmune diseases and cancer, and not only for psoriasis.

RESULTS/CONCLUSIONS

Small molecules that inhibit the activation of T lymphocytes, leukocyte trafficking, leukotriene activity/production and angiogenesis, and promote apoptosis have been patented. Small molecules that have been patented for the treatment of other autoimmune diseases and could be used for treating psoriasis are described. Moreover, other possible mechanistic approaches using small molecules are discussed.

Streptococcus sp. and Staphylococcus aureus isolates from patients with psoriasis possess genes that code for toxins (superantigens): clinical and therapeutic implications

Superantigens are powerful T lymphocyte-stimulating agents that are believed to contribute to the pathogenesis of certain diseases such as psoriasis. Toxins produced by Streptococcus pyogenes and Staphylococcus aureus are superantigens. The aim of this study was to detect genes that code for superantigens in Streptococcus and Staphylococcus aureus isolates from psoriatic patients. Primers to amplify streptococcal pyrogenic exotoxin A, B, and C and streptolysin O genes and staphylococcal enterotoxin A, B, C, and D genes were used. Streptococcal exotoxin B was detected in five streptococcal isolates. Staphyloccocus aureus enterotoxin A and/or C genes were detected in nine S. aureus isolates. Isolates from 13 of 22 patients possesed gene(s) that code for toxin(s) (superantigens). These results might support the role of superantigens in the exacerbation of psoriasis.

Psoriasis and vascular disease: an unsolved mystery

Psoriasis is an immune disease most commonly recognized for its skin and joint manifestations. These produce significant physical, social, and psychological distress in affected patients and resultant reductions in their quality of life. As expected, these concerns are vital in providing symptomatic improvement and in selecting an individualized therapy. Yet, the approach in management of these patients is likely to change given the growing body of evidence linking psoriasis and vascular disease. Stemming from an anecdotally described relationship, the association between psoriasis and vascular disease has become a focus of current research to further elucidate the pathophysiology underlying and connecting these two diseases. This article includes a review of the classical cardiovascular risk factors, the atherothrombotic markers, and the environmental stressors associated with psoriasis, as well as a critical review of the observed vascular diseases, the proposed mechanism of atherosclerosis, and the benefits of treatment of psoriasis.