d-Lysine reduces the non-enzymatic glycation of proteins in experimental diabetes mellitus in rats
1993; Springer Science+Business Media; Volume: 36; Issue: 9 Linguagem: Inglês
10.1007/bf00400352
ISSN1432-0428
AutoresM. Sensi, Maria Grazia Rossi, Francesco S. Celi, A. Cristina, C Rosati, David I. Perrett, D Andreani, Umberto Di Mario,
Tópico(s)Diet, Metabolism, and Disease
Resumod-Lysine, the non-physiological isomer of l-lysine, can competitively reduce protein non-enzymatic glycation in vitro. To study the effect of d-lysine in vivo, 6–8-week old Sprague-Dawley rats with streptozotocin-induced diabetes mellitus were treated from diagnosis for 45 days with two daily subcutaneous injections of d-lysine (0.5 g·ml−1·day−1). Another group of diabetic rats was only injected with equal volumes of physiological saline (0.9% NaCl). Glycated haemoglobin was measured by ion exchange chromatography, and glycated serum and lens proteins by boronate affinity gel chromatography. Serum and urinary creatinine concentrations were evaluated by the alkaline-picrate reaction. Urinary lysine concentrations at mid- and end-study were evaluated by cation exchange chromatography. Blood glucose concentrations, serum creatinine levels and creatinine clearances, measured at the end of the study, were similar in both diabetic groups (> 22.0 mmol/l, ≤ 106 μmol/l and ≈ 0.02 ml/s, respectively). Urinary lysine concentration in d-lysine-treated diabetic animals was more than 50-fold higher than in placebo-treated diabetic rats. In d-lysine-treated vs placebo-treated diabetic animals, a statistically significant reduction was found in the levels of glycated haemoglobin (stable HbA1; mean ± SD=3.00±0.74% vs 4.02±0.46%, p<0.05; labile HbA1=3.92±0.89% vs 5.84±0.61%, p<0.005), glycated serum proteins (1.40±0.47% vs 2.52±1.15%, p<0.05) and glycated lens proteins (4.90±0.96% vs 5.98±0.65 %,p<0.05). Thus, d-lysine (i) is not nephrotoxic and (ii) causes a significant reduction of the early glycation products at the protein level. Therefore, the d-amino acid could be useful in attempting to control damaging phenomena associated with or due to an enhanced protein non-enzymatic glycation.
Referência(s)