Characterization of the Metrnl Serum Levels in Patients with Inflammatory Bowel Disease and its Association with Inflammatory Cytokines

Background Meteorin-like (Metrnl) is a newly discovered adipokine with the anti-inflammatory and insulin sensitizing properties. Accordingly, Metrnl regulates glucose tolerance, enhances metabolism in body tissues, and induces thermogenesis in white adipose tissue. However, the correlation among Metrnl, IBD, and obesity still remains unexplored. Methods The present study was conducted on 54 healthy control, 42 Ulcerative Colitis (UC), and 43 Crohn's disease (CD) patients who were diagnosed by pathological examination. In these patients, serum levels of adiponectin, Metrnl, IL-6, and TNF-α were measured using ELISA kits. Results Metrnl concentration significantly decreased in both of the UC (85.25 ± 36.55 pg/mL) and CD (76.93 ± 27.92 pg/mL) patients compared to control group (107.52 ± 35.33 pg/mL). Similarly, adiponectin has also decreased in these two patient groups compared to the controls. However, IL-6 and TNF-α significantly increased in both of the patient groups. Moreover, Metrnl indicated an inverse relationship with BMI in the controls and both of the patient groups. In addition, there was an inverse correlation among Metrnl, IL-6, and TNF-α in both of the patient groups. Conclusions The current study is the first one reporting the decreased Metrnl serum level in the patients with IBD, which is inversely related to BMI, TNF-α, and IL-6. These results suggested a possible role for Metrnl in the pathogenesis of IBD, particularly through inflammation modulating.