Serum omentin and chemerin levels in patients with coronavirus disease 2019

Chemerin and omentin are adipokines secreted mainly by visceral adipose tissue, with pro- and anti-inflammatory properties, respectively. Their role in coronavirus disease 2019 (COVID-19) remains incompletely understood and available data are inconsistent.

This single-center case-control study included 40 hospitalized patients with COVID-19 and 24 non-COVID controls. Serum samples were collected in COVID-19 patients on admission (Day 0) and on Day 7 of hospitalization, and once in controls. Concentrations of omentin and chemerin and routine laboratory parameters were measured using enzyme immunoassays.

Compared with controls, patients with COVID-19 had higher inflammatory markers, including C-reactive protein, ferritin, interleukin-6 and D-dimer. Baseline serum omentin concentrations did not differ between COVID-19 patients and controls (363.6 [245.2-513.0] vs. 368.9 [254.1-468.8] ng/mL; p = 0.994), and remained stable between Day 0 and Day 7 (p = 0.605). In contrast, baseline chemerin levels were significantly higher in COVID-19 patients than in controls (234.3 [164.9-269.9] vs. 144.7 [98.0-213.2] ng/mL; p = 0.001) and remained elevated at Day 7 (243.7 [171.0-376.7] ng/mL, p = 0.001 vs. controls), with a non-significant trend toward an increase over time (Δ chemerin +42.6 ng/mL; p = 0.071).

In this cohort of hospitalized but predominantly non-critically ill patients, COVID-19 was associated with sustained elevation of circulating chemerin but not with alterations in omentin levels. Our findings are consistent with a potential role for chemerin, but not omentin, in the systemic inflammatory response to SARS-CoV-2 infection and complement previous reports describing divergent adipokine profiles in COVID-19.