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The therapeutic effects of Bombyx mori sericin on rat skin psoriasis through modulated epidermal immunity and attenuated cell proliferation

ABSTRACT:

Background and aim

Psoriasis is a skin disorder that leads to chronic inflammation and keratinocyte hyperproliferation. Sericin extracted from Bombyx mori cocoon has been demonstrated to possess anti-inflammatory and antiproliferative properties, which makes it a viable candidate for psoriasis treatment. This study aimed to investigate the therapeutic effect of sericin on skin psoriasis at the cellular level.

Experimental procedure

Imiquimod-induced skin psoriasis was established in Sprague-Dawley rats. The rats with psoriasis were divided into 6 groups (n = 5), namely, one nontreatment control group and five groups that received different treatments: sericin (2.5%, 5%, and 10%), 0.1% betamethasone, 3 μg/ml calcitriol. The treatments were administered twice daily for 7 days, followed by skin sample collection. Epidermal improvement and protein expression were evaluated using histopathological and label-free proteomic approaches and immunohistochemistry.

Results and conclusion

Compared with other concentrations, 10% sericin had the desired effect of improving skin psoriasis as shown by reduced epidermal thickness, similar to the effects of betamethasone and calcitriol treatments. Anti-inflammatory activity was shown by decreased C–C motif chemokine 20 (CCL20) expression posttreatment. Proteomic observation revealed that sericin reduced cytokine production by Th17 cells by interfering with the JAK-STAT signaling pathway. Sericin treatment also resulted in a modulated immune response via upregulation of Galectin-3 (Lgals3) and downregulation of Sphingosine-1-phosphate lyase1 (Sgpl1). Sericin improved epithelial cell proliferation by upregulating Nucleoside diphosphate kinase B (Nme2). Therefore, the therapeutic effect of sericin on psoriasis correlated with a reduced immune response and attenuated epidermal proliferation, making sericin a promising approach for skin psoriasis treatment. Graphical abstract Image 1 Highlights • Sericin extracted from Bombyx mori cocoon ameliorates skin psoriasis.• Sericin modulated immune response and epithelial cell proliferation in skin-psoriasis rat model.• Sericin upregulated Lgals3 and downregulated Sgpl1 in immune system.• Downregulated Nme2 of skin psoriasis by sericin treatment reduces epithelial cell proliferation.

SUBMITTER: Rujimongkon K

PROVIDER: S-EPMC8572706 | biostudies-literature |

REPOSITORIES: biostudies-literature

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