In:
The Journal of Clinical Endocrinology & Metabolism, The Endocrine Society, Vol. 107, No. 7 ( 2022-06-16), p. 1854-1864
Abstract:
Interleukin-6 (IL-6) is implicated in skeletal muscle wasting and in regulating skeletal muscle hypertrophy in the healthy state. Objective This work aimed to determine the role of IL-6 in regulating systemic protein and amino acid metabolism during rest, exercise, and recovery in lean and obese humans. Methods In a nonrandomized, single-blind design, 12 lean and 9 obese individuals were infused first with 0.9% saline (Saline), secondly with the IL-6 receptor antibody tocilizumab (Acute IL-6R ab), and 21 days later with saline while still under tocilizumab influence (Chronic IL-6R ab). Outcome measures were determined before, during, and after 90 minutes of exercise at 40% Wattmax by isotope dilution technique, using primed continuous infusion of L-[ring-D5]phenylalanine and L-[D2] tyrosine. Main outcomes measures included systemic protein turnover and plasma amino acid concentrations. Results We saw no effect of acute or chronic IL-6 receptor blockade on protein turnover. In lean individuals, chronic IL-6 receptor blockade increased plasma concentrations of total amino acids (rest Δ + 186 μmol/L; 95% CI, 40-332; recovery Δ + 201 μmol/L; 95% CI, 55-347) and essential amino acids (rest Δ + 43 μmol/L; 95% CI, 12-76; recovery Δ + 45 μmol/L; 95% CI, 13-77) independently of exercise but had no such effect in obese individuals (total amino acids rest Δ + 63 μmol/L; 95% CI, –170 to 295, recovery Δ – 23 μmol/L, 95% CI, –256 to 210; essential amino acids rest Δ + 26 μmol/L; 95% CI, –21 to 73, recovery Δ + 11 μmol/L; 95% CI, –36 to 58). Conclusion IL-6 receptor blockade has no effect on protein turnover in fasting lean and obese humans during rest, exercise, and recovery. Chronic IL-6 receptor blockade increases total and essential amino acid concentrations only in lean individuals.
Type of Medium:
Online Resource
ISSN:
0021-972X
,
1945-7197
DOI:
10.1210/clinem/dgac239
Language:
English
Publisher:
The Endocrine Society
Publication Date:
2022
detail.hit.zdb_id:
2026217-6
