This study explored the therapeutic effects and underlying mechanisms of polysaccharides and alkaloids from Dendrobium nobile Lindley (DNL) on psoriasis. An imiquimod (IMQ)-induced psoriasis mouse model was established to observe the pharmacological effects of DNLPs and DNLAs. The assessments included Psoriasis Area and Severity Index scoring, hematoxylin-eosin (HE) staining and immunohistochemistry, tyramide signal amplification, reverse transcription-quantitative polymerase chain reaction, and RNA sequencing (RNA-seq). The results showed that oral administration of DNLPs and DNLAs could effectively alleviate psoriasis symptoms and improve histopathological features. Transcriptomic analysis indicated that both components regulated immune responses and cellular functions, thereby reducing local inflammation through inhibition of myeloid leukocyte infiltration. Immunofluorescence results also verified that the expression of keratin markers K14, K16 and K17 was significantly downregulated, along with decreased levels of macrophage and neutrophil markers in the treatment groups. In conclusion, DNLPs and DNLAs exert prominent anti-inflammatory effects via modulating keratinocyte differentiation and suppressing the excessive activation of myeloid leukocytes. These findings provide a solid theoretical basis for the clinical application of Dendrobium nobile Lindley components in psoriasis therapy.

Huan Li, Ziyue Zhou, Qiuyang Chen, Lei Shi, Jingyuan Ma, Xingyue Li, Zhiyang Yu, Ying Yang, Jie Jing. Dendrobium nobile Lindley Ameliorates Psoriasis-Like Dermatitis by Modulating Keratinocyte Differentiation and Myeloid Leukocyte Activation. International Journal of Frontiers in Medicine (2026), Vol. 8, Issue 2: 11-24. https://doi.org/10.25236/IJFM.2026.080202.

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