The following is a summary of “Systemic redox status associates with disease activity and clinical phenotypes in Inflammatory Bowel Disease,” published in the January 2024 issue of Gastroenterology by Geertsema et al.

Reduced free thiols (FT) in circulating proteins, mainly albumin, reflect systemic oxidative stress in inflammatory bowel diseases (IBD), potentially as biomarkers for disease activity and therapy response.

Researchers conducted a retrospective study to explore how plasma FT relates to clinical features, inflammatory proteins, and medication use in individuals with IBD.

They analyzed plasma samples from 1,028 individuals with IBD, 567 with Crohn’s disease (CD), 461 with ulcerative colitis (UC), and 500 HCs participating in the 1000IBD and LifeLines projects. Samples were examined for levels of FT, uric acid, bilirubin, and 92 inflammation-related proteins using the Olink Inflammation panel ^O. All biomarkers were linked to clinical phenotypes through general linear models, adjusting for age, sex, body mass index, smoking, and medication use.

The results showed plasma levels of FT were significantly lower in IBD compared to HCs (P<0.05), with UC patients exhibiting even lower levels than CD patients (P<0.05). UC patients undergoing induction therapy had lower FT levels than maintenance therapy patients (P<0.05). Additionally, FT levels in IBD patients were strongly correlated with systemic inflammation, specifically C-reactive protein (CRP) levels (P<0.05). Reduced FT levels in both CD and UC patients were associated with elevated levels of inflammation-, apoptosis-, and growth factor-related proteins, including C-X-C motif chemokine 9 (CXCL9), CUB domain-containing protein 1 (CDCP1), and caspase-8 (CASP8), proteins previously linked to preclinical IBD^1-3. Moreover, in UC patients specifically, decreased FT levels were associated with elevated levels of eotaxin-1 (CCL11), monocyte chemotactic protein-1 (MCP-1), and various cytokine biomarkers such as Interleukin-6 (IL6) and Interleukin-17A (IL17A).

They concluded that FT levels linked to IBD activity and therapy in past studies, hinting at potential marker use. Findings suggest a complex interplay of oxidative stress in inflammation, furthering IBD understanding.

Source: academic.oup.com/ecco-jcc/article/18/Supplement_1/i584/7586385