Preliminary Study On The Role And Mechanism Of Ferroptosis Involved In The Abnormal Biological Behavior Of Keratinocytes In Psoriasis Vulgaris

Background: Psoriasis Vulgaris is a chronic and recurrent inflammatory skin disease with a total number of 6.5 million people in China,and there is no cure-all treatment.It is urgent to find new therapeutic targets,and strengthening the research on the pathogenesis and treatment of psoriasis vulgaris has important theoretical value and social significance.The pathogenesis of psoriasis is not completely clear,and the abnormal biological behavior of keratinocytes(KCs)is an important pathological manifestation of psoriasis.Ferroptosis is a new type of regulated cell death,which is characterized by lipid reactive oxygen accumulation,iron metabolism disorder,and lipid peroxidation.And glutathione peroxidase 4(GPX4)is the key negative regulatory gene in ferroptosis.Studies have shown that ferroptosis is involved in the pathophysiological process of many diseases,and inhibition or induction of ferroptosis can effectively intervene in related diseases.However,the relationship between KCs and ferroptosis in psoriasis vulgaris is unclear.Therefore,this study intends to explore the effect of ferroptosis on the biological behavior of KCs in psoriasis Vulgaris and its possible regulation mechanism on abnormal biological behavior by clinical samples,cells,and mice models,using RTqPCR,Western Blot,and immunohistochemistry.Objective: To explore the effect of ferroptosis on the biological behavior of KCs in psoriasis Vulgaris and its possible regulation mechanism on abnormal biological behavior.Methods:(1)We collected skin tissue from 23 patients with psoriasis vulgaris and 26 healthy subjects of matched sex and age and recorded psoriasis area and severity index(PASI)scores of the patients.We analyzed the difference between ferroptosis in psoriasis Vulgaris patients and healthy controls by RT-qPCR,Western Blot,and immunohistochemistry,and its correlation with the severity of psoriasis vulgaris patients.(2)HaCaT cells were cultured in vitro and treated with different concentrations of ferroptosis inducer RSL3.The changes in biological behaviors of HaCaT cells were observed by CCK8,reactive oxygen species(ROS)detection,apoptosis analysis,and Western Blot.On this basis,HaCaT cells were pretreated with a 5ng/ml M5 mixture(consisting of TNF-α,IL-1α,IL-17 A,IL-22,oncestatin-M cytokines)for 24 h to construct a psoriasislike cell model.And RSL3 with a concentration of 5μM was added for 24 h.Changes in keratin(KRT)6,filaggrin(FLG),inflammation,and chemokines(IL-17 A,IL-6,CXCL1,etc.)were detected by RT-qPCR.(3)The psoriasis-like mouse model induced by imiquimod(IMQ)was constructed,and the mice were randomly divided into blank control group(Ctrl),model group(IMQ),and ferroptosis inducer group(IMQ+RSL3),and solvent control group(IMQ+Vehicle).Each group was given a corresponding intervention.The changes in skin lesions in each group were observed,the PASI score was improved and photos were taken every day.On day 9,back skin lesions were collected for HE staining,RT-qPCR,and immunohistochemistry experiments.Results:(1)Compared with the normal control group,the oxidative product 4HNE increased and the expression level of GPX4,a key gene of ferroptosis,decreased in psoriasis vulgaris skin lesions(P<0.05).And the expression level was positively correlated with PASI scores(r=0.506,P<0.05).(2)After treatment with ferroptosis inducer RSL3,cell proliferation activity was decreased,ROS and apoptosis were increased,KRT6 expression was decreased and FLG expression was increased,and the difference was statistically significant(P<0.05).(3)RSL3 can alleviate IMQ-induced psoriatic dermatitis in mice,while the expression of KRT6 decreased,the expression of FLG increased,and the expression of inflammatory and chemokine factors decreased,with statistical significance(P<0.05).Conclusion:(1)This study to some extent verified the existence of ferroptosis in the skin lesions of patients with psoriasis vulgaris,and the occurrence degree of ferroptosis may be negatively correlated with the severity of the disease.(2)The use of ferroptosis inducer RSL3 can improve the abnormal biological behavior of KCs.(3)RSL3 can alleviate the phenotype of IMQ-induced psoriasis mouse models.