Huangqin Qingre Chubi Capsule modulates the lncRNA AP005432.1/PI3K/AKT axis and is associated with improved self-perception of patients and inflammation in ankylosing spondylitis

Ethnopharmacological relevance: Huangqin Qingre Chubi Capsule (HQC), a hospital preparation derived from the Jianpi Qingre Tongluo formula, has demonstrated therapeutic efficacy in ankylosing spondylitis (AS). However, its underlying mechanisms, particularly in relation to patient self-perception and the lncRNA AP005432.1/PI3K/Akt signaling axis, remain unclear.

Purpose: This study aimed to investigate the association between HQC exposure and improvements in self-perception of patients (SPP) and immune-inflammatory markers in individuals with AS. In addition, in vitro experiments were conducted to determine whether HQC attenuates inflammatory responses through modulation of the lncRNA AP005432.1/PI3K/Akt signaling pathway.

Methods: A retrospective analysis of 189 hospitalized patients with AS was performed to evaluate changes in SPP (SF-36, VAS, SAS, and SDS scores) and immune-inflammatory indicators before and after HQC treatment. Analysis of covariance (ANCOVA) was applied to adjust for age, sex, disease duration, concomitant medications, and comorbidities, with Bonferroni correction for multiple comparisons. Sensitivity analyses, including additional adjustment for height and weight and exclusion of biologic DMARD (bDMARD) users, were conducted to assess the robustness of the findings. Among the cohort, 20 patients with AS treated with HQC and 20 healthy controls were selected for molecular validation of lncRNA AP005432.1 expression and cytokine levels. In vitro experiments employed a co-culture model of peripheral blood mononuclear cells (PBMCs) from patients with AS and fibroblast-like synoviocytes (FLSs). The effects of HQC-containing serum, lncRNA AP005432.1 knockdown or overexpression, and PI3K/Akt pathway modulation on cell viability, inflammatory cytokines (TNF-α, IL-6, IL-17, IL-10), and pathway-related proteins (p-PI3K and p-AKT) were assessed using CCK-8 assays, ELISA, RT-qPCR, and Western blot analyses.

Results: Clinical observations demonstrated that HQC exposure was significantly associated with improvements in SPP scores and reductions in inflammatory markers, including ESR, Hs-CRP, and NLR. These associations remained significant after full adjustment for confounders and across sensitivity analyses, with the exception of the role-emotional (RE) domain of SF-36, which did not retain significance after Bonferroni correction. Molecular analyses revealed elevated expression of lncRNA AP005432.1 and increased levels of pro-inflammatory cytokines in patients with AS, both of which decreased following HQC treatment. In vitro experiments showed that PBMCs from patients with AS promoted FLS proliferation, upregulated lncRNA AP005432.1 expression, activated the PI3K/Akt signaling pathway, and enhanced the secretion of pro-inflammatory cytokines. These effects were reversed by HQC-containing serum or lncRNA AP005432.1 knockdown. Activation of the PI3K/Akt pathway attenuated the inhibitory effects of lncRNA AP005432.1 knockdown, whereas combined HQC treatment and lncRNA AP005432.1 knockdown enhances the inhibition of the activator-induced inflammatory responses.

Conclusion: HQC exposure is robustly associated with improved SPP and reduced inflammatory activity in AS after adjustment for multiple confounders. In vitro findings suggest that HQC may exert anti-inflammatory effects, at least in part, by downregulating lncRNA AP005432.1 and inhibiting activation of the PI3K/Akt signaling pathway. These results identify lncRNA AP005432.1 as a potential therapeutic target in AS and provide mechanistic support for further investigation of HQC.