Department of Biodynamic of Human Movement, School of Physical Education and Sports, University of Sao Paulo, Av. Prof. Mello Moraes, 65 Butanta, Sao Paulo, SP, 05508-030, Brazil.
Amino Acids. 2012 Jul;43(1):21-4. doi: 10.1007/s00726-011-1165-y. Epub 2011 Nov 27.
Carnosine is present in high concentrations in skeletal muscle where it contributes to acid buffering and functions also as a natural protector against oxidative and carbonyl stress. Animal studies have shown an anti-diabetic effect of carnosine supplementation. High carnosinase activity, the carnosine degrading enzyme in serum, is a risk factor for diabetic complications in humans. The aim of the present study was to compare the muscle carnosine concentration in diabetic subjects to the level in non-diabetics. Type 1 and 2 diabetic patients and matched healthy controls (total n=58) were included in the study. Muscle carnosine content was evaluated by proton magnetic resonance spectroscopy (3 Tesla) in soleus and gastrocnemius. Significantly lower carnosine content (-45%) in gastrocnemius muscle, but not in soleus, was shown in type 2 diabetic patients compared with controls. No differences were observed in type 1 diabetic patients. Type II diabetic patients display a reduced muscular carnosine content. A reduction in muscle carnosine concentration may be partially associated with defective mechanisms against oxidative, glycative and carbonyl stress in muscle.
肌肽在骨骼肌中含量很高，有助于酸碱缓冲，还具有抗氧化和羰基应激天然保护作用。动物研究表明，肌肽补充具有抗糖尿病作用。血清中肌肽降解酶肌肽酶活性高是糖尿病患者发生并发症的危险因素。本研究旨在比较糖尿病患者和非糖尿病患者的肌肉肌肽浓度。纳入了 1 型和 2 型糖尿病患者以及匹配的健康对照组（共 58 人）。通过质子磁共振波谱（3 Tesla）在比目鱼肌和腓肠肌评估肌肉肌肽含量。与对照组相比，2 型糖尿病患者腓肠肌的肌肽含量明显较低（-45%），而比目鱼肌没有差异。1 型糖尿病患者没有观察到差异。2 型糖尿病患者表现出肌肉肌肽含量减少。肌肉肌肽浓度降低可能与肌肉中抗氧化、糖基化和羰基应激的缺陷机制部分相关。
