Effects of blood glucose fluctuation on skin biophysical properties, structure and antioxidant status in an animal model

Background. Intermittent blood-glucose fluctuation (BGF) can accelerate diabetes and its complications, but it is still unknown whether BGF can damage the skin of patients with diabetes. Aim. To investigate the effects of repetitive fluctuation in blood glucose concentration on the biophysical properties, structure and antioxidant capacity of diabetic mouse skin. Methods. Mice with alloxan-induced diabetes were injected with glucose three times daily to induce repetitive BGF. Six weeks later, skin elasticity and skin hydration were measured to evaluate skin water-holding capacity and contraction function. The histological changes of skin were also studied, using haematoxylin and eosin. In addition, we compared levels of blood sugar and advanced glycation end products (AGEs), the activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA) and hydroxyproline in the skin of normal mice and diabetic mice with or without BGF. Results. The diabetic mice with BGF displayed an 18.6% increase in blood sugar level, an 11.3% increase in AGEs content and a 13.1% increase in MDA content compared with the diabetic mice (P < 0.01). There was a greater reduction in skin elasticity, skin hydration, hydroxyproline content and SOD activity in the diabetic mice with BGF (P < 0.01). Histological examination showed that BGF enhanced skin lesions in diabetic mice. Conclusions. Repetitive fluctuation in blood-glucose concentration produced a marked detrimental effect on skin structure and function in diabetic mice. The deleterious effects of BGF on skin appeared to due at least partly to the oxidative stress.