Circulating levels of inflammatory cytokines in patients with psoriasis vulgaris of different Chinese medicine syndromes.

Objective: To investigate whether the serum levels of inflammation-related cytokines might be different between the healthy individuals and the psoriatic patients diagnosed of three varied Chinese medicine (CM) syndromes [blood-stasis syndrome (BSS), blood-dryness syndrome (BDS) and wind-heat syndrome (WHS)].

Methods: A total of 62 psoriatic patients were recruited and assigned to 3 groups according to their CM syndromes, including 27 patients of BSS, 21 of BDS and 14 of WHS. Another 20 sex- and age-matched healthy subjects were enrolled into the control group. Serum concentrations of multiple cytokines, including monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α (MIP-1α), soluble CD4O ligand (SCD40L), tumor necrosis factor-α (TNF-α), epidermal growth factor (EGF), interleukin-8 (IL-8), interleukin-17 (IL-17), interferon γ inducible protein-10 (IP-10) and vascular endothelial growth factor (VEGF), were measured by a multiplexed flow cytometric assay.

Results: The circulating levels of MIP-1α, TNF-α, IL-8, and IP-10 were significantly increased in the psoriatic patients compared with the healthy controls (P<0.01). Male and female patients tended to have higher serum levels of MCP-1 and IP-10, respectively (P<0.05). Interestingly, compared with the control group, 6 out of the 9 cytokines (MCP-1, MIP-1α, TNF-α, EGF, IL-8 and IP-10) were substantially increased in the BSS group (P<0.05 or P<0.01), whereas only MIP-1α and IL-8 levels were elevated in the BDS group (P<0.05 or P<0.01) concurrent with lowered concentrations of SCD40L and IL-17 (P<0.05). In the WHS group, MIP-1α was the only cytokine whose level was evidently increased (P<0.01), in contrast to IL-17 which was decreased as compared with the control (P<0.05). The psoriatic patients overall owned higher levels of MIP-1α and IL-8 in the circulation which were comparable among the 3 groups of CM syndromes (P<0.01). In contrast, TNF-α level of the BSS group was the highest among the three (P<0.01), followed by the BDS and the WHS groups.

Conclusions: The expression profiles of cytokines in the circulation might not be necessarily identical for psoriatic patients with different CM syndromes. Accordingly, the serum concentrations of certain cytokines could potentially be used as the ancillary indices for the clinical classification of psoriatic CM syndromes.