Photodynamic therapy with 5-aminolevulinic acid suppresses IFN-γ-induced K17 expression in HaCaT cells via MAPK
1Department of Dermatology, Qilu Hospital, Shandong University, Jinan, China. sunqingql@sina.com.
Objective:
Psoriasis is a chronic inflammatory skin disorder that greatly affects the patient's quality of life. Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) has recently been applied for inflammatory dermatoses including psoriasis. However, the therapeutic effect of ALA-PDT is yet to be validated, and the underlying mechanisms remain unclear.
Materials And Methods:
In this study, a psoriatic model was established by treating HaCaT cells with 250 U/ml IFN-γ for 48 h. The effect of ALA-PDT treatment on HaCaT cell viability was assessed using MTT assay. The levels of p38, JNK, and ERK, as well as their phosphorylation status (P-p38, P-JNK, P-ERK), were assessed by immunoblotting.
Results:
Our data indicate that ALA-PDT can significantly inhibit the proliferation of IFN-g-treated HaCaT cells and the expression of keratin 17, both in a dose- and time-dependent manner. Furthermore, ALA-PDT can activate the MAPK pathway, and promote the expression of p38, JNK, and ERK. ALA-PDT showed pro-apoptotic effects by enhancing cell apoptosis and upregulating the apoptotic genes PARP and caspase 3.
Conclusions:
Taken together, these findings indicate the possible pathways involved in ALA-PDT-mediated effects and highlight the potential of ALA-PDT in the development of novel therapeutic strategies.
Insights
Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) effectively inhibits psoriasis cell proliferation and promotes apoptosis. This study elucidates the underlying mechanisms involving MAPK pathway activation, suggesting ALA-PDT as a potential psoriasis treatment.
Area of Science:
- Dermatology
- Cell Biology
- Biochemistry
Background:
- Psoriasis is a chronic inflammatory skin disease impacting quality of life.
- 5-aminolevulinic acid photodynamic therapy (ALA-PDT) shows promise for inflammatory dermatoses.
- The efficacy and mechanisms of ALA-PDT for psoriasis require further investigation.
Purpose of the Study:
- To investigate the therapeutic effects of ALA-PDT on a psoriasis model.
- To elucidate the molecular mechanisms underlying ALA-PDT's action in psoriasis.
Main Methods:
- A psoriatic model was induced in HaCaT cells using IFN-γ.
- Cell viability was assessed via MTT assay.
- Protein expression and phosphorylation (MAPK pathway) were analyzed using immunoblotting.
Main Results:
- ALA-PDT significantly inhibited HaCaT cell proliferation and keratin 17 expression.
- ALA-PDT activated the MAPK pathway, increasing p38, JNK, and ERK expression.
- ALA-PDT induced apoptosis by upregulating PARP and caspase 3.
Conclusions:
- ALA-PDT demonstrates significant anti-proliferative and pro-apoptotic effects in a psoriasis model.
- MAPK pathway activation is a key mechanism in ALA-PDT's therapeutic action.
- ALA-PDT holds potential as a novel therapeutic strategy for psoriasis.
